Search results for: total ownership cost

Authors: Orkide Donma, Mustafa M. Donma

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Childhood obesity, which may lead to increased risk for heart diseases in children as well as adults, is one of the most important health problems throughout the world. Prevalences of morbid obesity and metabolic syndrome (MetS) are being increased during childhood age group. MetS is a cluster of metabolic and vascular abnormalities including hypercoagulability and an increased risk of cardiovascular diseases (CVDs). There are also some relations between some components of MetS and leukocytes. The aim of this study is to investigate complete blood cell count parameters that differ between morbidly obese boys and girls with MetS diagnosis. A total of 117 morbid obese children with MetS consulted to Department of Pediatrics in Faculty of Medicine Hospital at Namik Kemal University were included into the scope of the study. The study population was classified based upon their genders (60 girls and 57 boys). Their heights and weights were measured and body mass index (BMI) values were calculated. WHO BMI-for age and sex percentiles were used. The values above 99 percentile were defined as morbid obesity. Anthropometric measurements were performed. Waist-to-hip and head-to-neck ratios as well as homeostatic model assessment of insulin resistance (HOMA-IR) were calculated. Components of MetS (central obesity, glucose intolerance, high blood pressure, high triacylglycerol levels, low levels of high density lipoprotein cholesterol) were determined. Hematological variables were measured. Statistical analyses were performed using SPSS. The degree for statistical significance was p ≤ 0.05. There was no statistically significant difference between the ages (11.2±2.6 years vs 11.2±3.0 years) and BMIs (28.6±5.2 kg/m² vs 29.3±5.2 kg/m²) of boys and girls (p ≥ 0.05), respectively. Significantly increased waist-to-hip ratios were obtained for boys (0.94±0.08 vs 0.91±0.06; p=0.023). Significantly elevated values of hemoglobin (13.55±0.98 vs 13.06±0.82; p=0.004), mean corpuscular hemoglobin concentration (33.79±0.91 vs 33.21±1.14; p=0.003), eosinophils (0.300±0.253 vs 0.196±0.197; p=0.014), and platelet (347.1±81.7 vs 319.0±65.9; p=0.042) were detected for boys. There was no statistically significant difference between the groups in terms of neutrophil/lymphocyte ratios as well as HOMA-IR values (p ≥ 0.05). Statistically significant gender-based differences were found for hemoglobin as well as mean corpuscular hemoglobin concentration and hence, separate reference intervals for two genders should be considered for these parameters. Eosinophils may contribute to the development of thrombus in acute coronary syndrome. Eosinophils are also known to make an important contribution to mechanisms related to thrombosis pathogenesis in acute myocardial infarction. Increased platelet activity is observed in patients with MetS and these individuals are more susceptible to CVDs. In our study, elevated platelets described as dominant contributors to hypercoagulability and elevated eosinophil counts suggested to be related to the development of CVDs observed in boys may be the early indicators of the future cardiometabolic complications in this gender.

Keywords: children, complete blood count, gender, metabolic syndrome

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Authors: Salam N. Abdo, Orien L. Tulp, George P. Einstein

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The purpose of this exploratory study was to gather the insights into psoriasis etiology, treatment, and patient experience, for developing psoriasis and psoriatic arthritis diagnostic test. Data collection methods consisted of a comprehensive meta-analysis of relevant studies and psoriasis patient survey. Established meta-analysis guidelines were used for the selection and qualitative comparative analysis of psoriasis and psoriatic arthritis research studies. Only studies that clearly discussed psoriasis etiology, treatment, and patient experience were reviewed and analyzed, to establish a qualitative data base for the study. Using the insights gained from meta-analysis, an existing psoriasis patient survey was modified and administered to collect additional data as well as triangulate the results. The hypothesis is that specific types of psoriatic disease have specific etiology and pathophysiologic pattern. The following etiology categories were identified: bacterial, environmental/microbial, genetic, immune, infectious, trauma/stress, and viral. Additional results, obtained from meta-analysis and confirmed by patient survey, were the common age of onset (early to mid-20s) and type of psoriasis (plaque; mild; symmetrical; scalp, chest, and extremities, specifically elbows and knees). Almost 70% of patients reported no prescription drug use due to severe side effects and prohibitive cost. These results will guide the development of psoriasis and psoriatic arthritis diagnostic test. The significant number of medical publications classified psoriatic arthritis disease as inflammatory of an unknown etiology. Thus numerous meta-analyses struggle to report any meaningful conclusions since no definitive results have been reported to date. Therefore, return to the basics is an essential step to any future meaningful results. To date, medical literature supports the fact that psoriatic disease in its current classification could be misidentifying subcategories, which in turn hinders the success of studies conducted to date. Moreover, there has been an enormous commercial support to pursue various immune-modulation therapies, thus following a narrow hypothesis/mechanism of action that is yet to yield resolution of disease state. Recurrence and complications may be considered unacceptable in a significant number of these studies. The aim of the ongoing study is to focus on a narrow subgroup of patient population, as identified by this exploratory study via meta-analysis and patient survey, and conduct an exhaustive work up, aiming at mechanism of action and causality before proposing a cure or therapeutic modality. Remission in psoriasis has been achieved and documented in medical literature, such as immune-modulation, phototherapy, various over-the-counter agents, including salts and tar. However, there is no psoriasis and psoriatic arthritis diagnostic test to date, to guide the diagnosis and treatment of this debilitating and, thus far, incurable disease. Because psoriasis affects approximately 2% of population, the results of this study may affect the treatment and improve the quality of life of a significant number of psoriasis patients, potentially millions of patients in the United States alone and many more millions worldwide.

Keywords: biologics, early diagnosis, etiology, immune disease, immune modulation therapy, inflammation skin disorder, phototherapy, plaque psoriasis, psoriasis, psoriasis classification, psoriasis disease marker, psoriasis diagnostic test, psoriasis marker, psoriasis mechanism of action, psoriasis treatment, psoriatic arthritis, psoriatic disease, psoriatic disease marker, psoriatic patient experience, psoriatic patient quality of life, remission, salt therapy, targeted immune therapy

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Authors: Vita Krungleviciute, Rasa Zelvyte, Ingrida Monkeviciene, Jone Kantautaite, Rolandas Stankevicius, Modestas Ruzauskas, Elena Bartkiene

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The environmental impact of agricultural bioproducts from the processing of food crops is an increasing concern worldwide. Currently, cereal bran has been used as a low-value ingredient for both human consumption and animal feed. The most popular bioprocessing technologies for cereal bran nutritional and technological functionality increasing are enzymatic processing and fermentation, and the most popular starters in fermented feed production are lactic acid bacteria (LAB) including pediococci. However, the ruminant digestive system is unique, there are billions of microorganisms which help the cow to digest and utilize nutrients in the feed. To achieve efficient feed utilization and high milk yield, the microorganisms must have optimal conditions, and the disbalance of this system is highly undesirable. Pediococcus strains Pediococcus acidilactici BaltBio01 and Pediococcus pentosaceus BaltBio02 from spontaneous fermented rye were isolated (by rep – PCR method), identified, and characterized by their growth (by Thermo Bioscreen C automatic turbidometer), acidification rate (2 hours in 2.5 pH), gas production (Durham method), and carbohydrate metabolism (by API 50 CH test ). Antimicrobial activities of isolated pediococcus against variety of pathogenic and opportunistic bacterial strains previously isolated from diseased cattle, and their resistance to antibiotics were evaluated (EFSA-FEEDAP method). The isolated pediococcus strains were cultivated in barley/wheat bran (90 / 10, m / m) substrate, and developed supplements, with high content of valuable pediococcus, were used for Lithuanian black and white dairy cows feeding. In addition, the influence of supplements on milk production and composition was determined. Milk composition was evaluated by the LactoScope FTIR” FT1.0. 2001 (Delta Instruments, Holland). P. acidilactici BaltBio01 and P. pentosaceus BaltBio02 demonstrated versatile carbohydrate metabolism, grown at 30°C and 37°C temperatures, and acidic tolerance. Isolated pediococcus strains showed to be non resistant to antibiotics, and having antimicrobial activity against undesirable microorganisms. By barley/wheat bran utilisation using fermentation with selected pediococcus strains, it is possible to produce safer (reduced Enterobacteriaceae, total aerobic bacteria, yeast and mold count) feed stock with high content of pediococcus. Significantly higher milk yield (after 33 days) by using pediococcus supplements mix for dairy cows feeding could be obtained, while similar effect by using separate strains after 66 days of feeding could be achieved. It can be stated that barley/wheat bran could be used for higher value feed production in order to increase milk production. Therefore, further research is needed to identify what is the main mechanism of the positive action.

Keywords: barley/wheat bran, dairy cattle, fermented feed, milk, pediococcus

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Authors: Sachil Kumar, Anoop Kumar Verma, Wahid Ali, Uma Shankar Singh

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Globally approximately 55.3 million people die each year. In the India there were 95 lakh annual deaths in 2013. The number of deaths resulted from homicides, suicides and unintentional injuries in the same period was about 5.7 lakh. The ever-increasing crime rate necessitated the development of methods for determining time since death. An erroneous time of death window can lead investigators down the wrong path or possibly focus a case on an innocent suspect. In this regard a research was carried out by analyzing the temperature dependent degradation of a Cardiac Troponin-T protein (cTnT) in the myocardium postmortem as a marker for time since death. Cardiac tissue samples were collected from (n=6) medico-legal autopsies, (in the Department of Forensic Medicine and Toxicology, King George’s Medical University, Lucknow India) after informed consent from the relatives and studied post-mortem degradation by incubation of the cardiac tissue at room temperature (20±2 OC), 12 0C, 25 0C and 37 0C for different time periods ((~5, 26, 50, 84, 132, 157, 180, 205, and 230 hours). The cases included were the subjects of road traffic accidents (RTA) without any prior history of disease who died in the hospital and their exact time of death was known. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS-PAGE) and visualization by Western blot using cTnT specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc. The data shows a distinct temporal profile corresponding to the degradation of cTnT by proteases found in cardiac muscle. The disappearance of intact cTnT and the appearance of lower molecular weight bands are easily observed. Western blot data clearly showed the intact protein at 42 kDa, two major (27 kDa, 10kDa) fragments, two additional minor fragments (32 kDa) and formation of low molecular weight fragments as time increases. At 12 0C the intensity of band (intact cTnT) decreased steadily as compared to RT, 25 0C and 37 0C. Overall, both PMI and temperature had a statistically significant effect where the greatest amount of protein breakdown was observed within the first 38 h and at the highest temperature, 37 0C. The combination of high temperature (37 0C) and long Postmortem interval (105.15 hrs) had the most drastic effect on the breakdown of cTnT. If the percent intact cTnT is calculated from the total area integrated within a Western blot lane, then the percent intact cTnT shows a pseudo-first order relationship when plotted against the log of the time postmortem. These plots show a good coefficient of correlation of r = 0.95 (p=0.003) for the regression of the human heart at different temperature conditions. The data presented demonstrates that this technique can provide an extended time range during which Postmortem interval can be more accurately estimated.

Keywords: degradation, postmortem interval, proteolysis, temperature, troponin

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Authors: Christa Fricke, Sibylle Meyer, Gert G. Wagner

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Our research focuses on the question of whether assistive and social robotics could pose a promising strategy to support the independent living of elderly people and potentially relieve relatives of any anxieties. To answer the question of how elderly people perceive the potential of robotics, we analysed the data from the Berlin Aging Study BASE-II (https://www.base2.mpg.de/de) (N=1463) and data from the German SYMPARTNER study (http://www.sympartner.de) (N=120) and compared those to a control group made up of people younger than 30 years (BASE II: N=241; SYMPARTNER: N=30). BASE-II is a cohort study of people living in Berlin, Germany. The sample covers more than 2200 cases; a questionnaire on the use and acceptance of assistive and social robots was carried out with a sub-sample of 1463 respondents in 2015. The SYMPARTNER study was done by SIBIS institute of Social Research, Berlin and included a total of 120 persons between the ages of 60 and 87 in Berlin and the rural German federal state of Thuringia. Both studies included a control group of persons between the ages of 20 and 35 (BASE II: N=241; SYMPARTNER: N=30). Additional data, representative for the whole population in Germany, will be surveyed in fall 2017 (Survey “Technikradar” [technology radar] by the National Academy of Science and Engineering). Since this survey is including some identical questions as BASE-II/SYMPARTNER, comparative results can be presented at 20th International Conference on Social Robotics in New York 2018. The complexity of the data gathered in BASE-II and SYMPARTNER, encompassing detailed socio-economic background characteristics as well as personality traits such as the personal attitude to risk taking, locus of control and Big Five, proves highly valuable and beneficial. Results show that participants’ expressions of resentment against robots are comparatively low. Participants’ personality traits play a role, however the effect sizes are small. Only 15 percent of participants received domestic robots with great scepticism. Participants aged older than 70 years expressed greatest rejection of the robotic assistant. The effect sizes however account for only a few percentage points. Overall, participants were surprisingly open to the robot and its usefulness. The analysis also shows that men’s acceptance of the robot is generally greater than that of women (with odds ratios of about 0.6 to 0.7). This applies to both assistive robots in the private household and in care environments. Men expect greater benefits of the robot than women. Women tend to be more sceptical of their technical feasibility than men. Interview results prove our hypothesis that men, in particular of the age group 60+, are more accustomed to delegate household chores to women. A delegation to machines instead of humans, therefore, seems palpable. The answer to the title question of this planned presentation is: social and assistive robots at home robots are not only accepted by men – but by fewer women than men.

Keywords: acceptance, care, gender, household

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Authors: Makhan Maharjan, Mani Ulaganathan, Vanchiappan Aravindan, Srinivasan Madhavi, Jing-Yuan Wang, Tuti Mariana Lim

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The ever-increasing energy demand has made research to develop high performance energy storage systems that are able to fulfill energy needs. Supercapacitors have potential applications as portable energy storage devices. In recent years, there have been huge research interests to enhance the performances of supercapacitors via exploiting novel promising carbon precursors, tailoring textural properties of carbons, exploiting various electrolytes and device types. In this work, we employed orange peel (waste material) as the starting material and synthesized activated carbon by pyrolysis of KOH impregnated orange peel char at 800 °C in argon atmosphere. The resultant orange peel-derived activated carbon (OP-AC) exhibited BET surface area of 1,901 m² g-1, which is the highest surface area so far reported for the orange peel. The pore size distribution (PSD) curve exhibits the pores centered at 11.26 Å pore width, suggesting dominant microporosity. The high surface area OP-AC accommodates more ions in the electrodes and its well-developed porous structure facilitates fast diffusion of ions which subsequently enhance electrochemical performance. The OP-AC was studied as positive electrode in combination with different negative electrode materials, such as pre-lithiated graphite (LiC6) and Li4Ti5O12 for making hybrid capacitors. The lithium ion capacitor (LIC) fabricated using OP-AC with pre-lithiated graphite delivered high energy density of ~106 Wh kg–1. The energy density for OP-AC||Li4Ti5O12 capacitor was ~35 Wh kg⁻¹. For comparison purpose, configuration of OP-AC||OP-AC capacitors were studied in both aqueous (1M H2SO4) and organic (1M LiPF6 in EC-DMC) electrolytes, which delivered the energy density of 8.0 Wh kg⁻¹ and 16.3 Wh kg⁻¹, respectively. The cycling retentions obtained at current density of 1 A g⁻¹ were ~85.8, ~87.0 ~82.2 and ~58.8% after 2500 cycles for OP-AC||OP-AC (aqueous), OP-AC||OP-AC (organic), OP-AC||Li4Ti5O12 and OP-AC||LiC6 configurations, respectively. In addition, characterization studies were performed by elemental and proximate composition, thermogravimetry analysis, field emission-scanning electron microscopy, Raman spectra, X-ray diffraction (XRD) pattern, Fourier transform-infrared, X-ray photoelectron spectroscopy (XPS) and N2 sorption isotherms. The morphological features from FE-SEM exhibited well-developed porous structures. Two typical broad peaks observed in the XRD framework of the synthesized carbon implies amorphous graphitic structure. The ratio of 0.86 for ID/IG in Raman spectra infers high degree of graphitization in the sample. The band spectra of C 1s in XPS display the well resolved peaks related to carbon atoms in various chemical environments. The presence of functional groups is also corroborated from the FTIR spectroscopy. Characterization studies revealed the synthesized carbon to be promising electrode material towards the application for energy storage devices. Overall, the intriguing properties of OP-AC make it a new alternative promising electrode material for the development of high energy lithium ion capacitors from abundant, low-cost, renewable biomass waste. The authors gratefully acknowledge Agency for Science, Technology and Research (A*STAR)/ Singapore International Graduate Award (SINGA) and Nanyang Technological University (NTU), Singapore for funding support.

Keywords: energy storage, lithium-ion capacitors, orange peels, porous activated carbon

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Authors: Edda E. Falcone, Cinzia Federico, Sergio Bellomo, Lorenzo Brusca, Manfredi Longo, Walter D’Alessandro

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Although trace metals are an essential element for living beings, they can become toxic at high concentrations. Their potential toxicity is related not only to the total content in the environment but mostly upon their bioavailability. Volcanoes are important natural metal emitters and they can deeply affect the quality of air, water and soils, as well as the human health. Trace metals tend to accumulate in the tissues of living organisms, depending on the metal contents in food, air and water and on the exposure time. Birds are considered as bioindicators of interest, because their feathers directly reflects the metals uptake from the blood. Birds are exposed to the atmospheric pollution through the contact with rainfall, dust, and aerosol, and they accumulate metals over the whole life cycle. We report on the first data combining the rainfall metal content in three different areas of Mt Etna, variably fumigated by the volcanic plume, and the metal contents in the feathers of pigeons, collected in the same areas. Rainfall samples were collected from three rain gauges placed at different elevation on the Eastern flank of the volcano, the most exposed to airborne plume, filtered, treated with HNO₃ Suprapur-grade and analyzed for Fe, Cr, Co, Ni, Se, Zn, Cu, Sr, Ba, Cd and As by ICP-MS technique, and major ions by ion chromatography. Feathers were collected from single individuals, in the same areas where the rain gauges were installed. Additionally, some samples were collected in an urban area, poorly interested by the volcanic plume. The samples were rinsed in MilliQ water and acetone, dried at 50°C until constant weight and digested in a mixture of 2:1 HNO₃ (65%) - H₂O₂ (30%) Suprapur-grade for 25-50 mg of sample, in a bath at near-to-boiling temperature. The solutions were diluted up to 20 ml prior to be analyzed by ICP-MS. The rainfall samples most contaminated by the plume were collected at close distance from the summit craters (less than 6 km), and show lower pH values and higher concentrations for all analyzed metals relative to those from the sites at lower elevation. Analyzed samples are enriched in both metals directly emitted by the volcanic plume and transported by acidic gases (SO₂, HCl, HF), and metals leached from the airborne volcanic ash. Feathers show different patterns in the different sites related to the exposure to natural or anthropogenic pollutants. They show abundance ratios similar to rainfall for lithophile elements (Ba, Sr), whereas are enriched in Zn and Se, known for their antioxidant properties, probably as adaptive response to oxidative stress induced by toxic metal exposure. The pigeons revealed a clear heterogeneity of metal uptake in the different parts of the volcano, as an effect of volcanic plume impact. Additionally, some physiological processes can modify the fate of some metals after uptake and this offer some insights for translational studies.

Keywords: bioindicators, environmental pollution, feathers, trace metals, volcanic plume

Procedia PDF Downloads 142

Authors: Amina Sa'id Muhammad, Asmau Ishaq Alhassan, Beba Raymond, Fatima Bello

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Severe acute malnutrition (SAM) remains a major killer of children under five years of age. Nigeria has the second highest burden of stunted children in the world, with a national prevalence rate of 32 percent of children under five. An estimated 2 million children in Nigeria suffer from severe acute malnutrition (SAM), and 3.9% of children in northwest Nigeria suffer from SAM, which is significantly higher than the national average of 2.1%. Community-Based Management of Acute Malnutrition (CMAM) has proven to be an effective intervention in the treatment of SAM in children using Ready-to-Use Therapeutic Food (RUTF). Ready-to-use therapeutic food (RUTF) is a key component for the treatment of Severe Acute Malnutrition. It contains all the energy and nutrients required for rapid catch-up growth and used particularly in the treatment of children over 6 months of age with SAM without medical complications. However, almost all RUTFs are currently imported to Nigeria from other countries. Shortages of RUTF due to logistics (shipping costs, delays, donor fatigue etc) and funding issues present a threat to the achievement of the 2030 World Health Assembly (WHA) targets for reducing malnutrition in addition to 2030 SDGs 2 (Zero Hunger), 3 (Good Health and Wellbeing), 12 (Responsible Consumption and Production), and 17 (Partnerships for the Goals), thus undermining its effectiveness in combating malnutrition On the other hand, the availability of human and material resources that will aid local production of RUTF presents an opportunity to fill in the gap in regular RUTF supply. About one thousand Nigerian children die of malnutrition-related causes every day, reaching a total of 361,000 each year. Owing to the high burden of malnutrition in Nigeria, the local production of RUTF is a logical step, that will ensure increased availability, acceptability, access, and efficiency in supply, and at lower costs. Objective(s): The objectives of this study were therefore, to formulate RUTF from locally available resources and to determine its energy and nutrients composition, incommensurate with the standard/commercial RUTF. Methods: Three samples of RUTF were formulated using locally available resources (soya beans, wheat, rice, baobab, brown-sugar, date palm and soya oil); which were subjected to various analysis to determine their energy/proximate composition, vitamin and mineral contents and organoleptic properties were also determined using sensory evaluation. Results: The energy values of the three samples of locally produced RUTF were found to be in conformity with WHO recommendation of ≥ 500 kcal per 100g. The energy values of the three RUTF samples produced in the current study were found to be 563.08, 503.67 and 528.98 kcal respectively. Sample A, B and C had protein content of 13.56% 16.71% and 14.62% respectively, which were higher than that of commercial RUTF (10.9%). Conclusions/recommendations: The locally formulated RUTF samples had energy value of more than 500 kcal per 100g; with an appreciable amount of macro and micro nutrients. The appearance, taste, flavor and general acceptability of the formulated RUTF samples were also commendable.

Keywords: energy, malnutrition, nutrients, RUTF

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Authors: Afentoula Mavrodi, Andreas Georgiou, Georgios Tsiotras, Vassilis Aletras

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Placing a monetary value on a quality-adjusted-life-year (QALY) is of utmost importance in economic evaluation. Identifying the population’s preferences is critical in order to understand some of the reasons driving variations in the assigned monetary value. Yet, evidence of the motives behind value assignment to a QALY by the general public is limited. Developing an instrument that would capture the population’s motives could be proven valuable to policy-makers, to guide them in allocating different values to a QALY based on users’ motivations. The aim of this study was to identify the most relevant motives and develop an appropriate instrument to assess them. To design the instrument, we employed: a) the EQ-5D-3L tool to assess participants’ current health status, and b) the Willingness-to-Pay (WTP) approach, within the Contingent Valuation (CV) Method framework, to elicit the monetary value. Advancing the open-ended approach adopted to assess solely protest bidders’ motives; a variety of follow-up item-specific statements were designed (deductive approach), aiming to evaluate motives of both protest bidders and participants willing to pay for the hypothetical treatment under consideration. The initial design of the survey instrument was the outcome of an extensive literature review. This instrument was revised based on 15 semi-structured interviews that took place in September 2018 and a pilot study held during two months (October-November) in 2018. Individuals with different educational, occupational and economical backgrounds and adequate verbal skills were recruited to complete the semi-structured interviews. The follow-up motivation statements of both protest bidders and those willing to pay were revised and rephrased after the semi-structured interviews. In total 4 statements for protest bidders and 3 statements for those willing to pay for the treatment were chosen to be included in the survey tool. Using the CATI (Computer Assisted Telephone Interview) method, a randomly selected sample of 97 persons living in Thessaloniki, Greece, completed the questionnaire on two occasions over a period of 4 weeks. Based on pilot study results, a test-retest reliability assessment was performed using the intra-class correlation coefficient (ICC). All statements formulated for protest bidders showed acceptable reliability (ICC values of 0.84 (95% CI: 0.67, 0.92) and above). Similarly, all statements for those willing to pay for the treatment showed high reliability (ICC values of 0.86 (95% CI: 0.78, 0.91) and above). Overall, the instrument designed in this study was reliable with regards to the item-specific statements assessing participants’ motivation. Validation of the instrument will take place in a future study. For a holistic WTP per QALY instrument, participants’ motivation must be addressed broadly. The instrument developed in this study captured a variety of motives and provided insight with regards to the method through which the latter are evaluated. Last but not least, it extended motive assessment to all study participants and not only protest bidders.

Keywords: contingent valuation method, instrument, motives, quality-adjusted life-year, willingness-to-pay

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Authors: Faith O. Olanrewaju

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Internal displacement and the vulnerability of women are two critical aspects of forced migration that have dominated both global and local discourses. Statistics show that in November 2021, there were over 2.1 million internally displaced persons (IDPs) in Nigeria. Literature also states that displaced women and girls are more vulnerable than displaced men. They are susceptible to adversative experiences, including various forms of sexual violence and rape. As a result, the displaced women and girls are faced with psychological and physical traumas, including HIV/AIDS as well as unexpected or poorly spaced pregnancies. In addition, the poor condition of living of internally displaced women in IDP camps affects their reproductive health, pregnancy outcomes, and maternal mortality levels. Incontrovertibly, internally displaced women constitute an imperative contributor to the ills of Nigeria's maternal health status, which is the second worse globally and the worst in Africa. World Health Organisation statistics showed that approximately 536,000 girls and women die from pregnancy-related causes globally, and Nigeria accounts for 14% of the global maternal deaths. Undeniably, this supports the claims that maternal mortality remains a challenge in Nigeria and can be exacerbated by internal displacement crises. Therefore, maternal mortality remains a critical impediment to the actualisation of the 3.1 SDG target. Owing to this, concerns arise about the quality of the policy in Nigeria’s health sector. More specifically, this study is concerned with the maternal health care services displaced women receive in IDP camps in the three states affected by internal displacement in north-central Nigeria, an understudied area. The novelty of the study also lies in its comparative investigation of maternal healthcare service delivery in three different camp structures (faith-based, government, and informal IDP camps), a pattern that is absent in literature. Therefore, this study will investigate how the camp structures affect access to maternal health services in the study areas; analyse the successes and challenges in the delivery of maternal health care services to displaced women in the various camps; and recommendation and strategies for reducing maternal healthcare disparities/gaps across IDP camps in Nigeria (should they exist). It will adopt a mixed-method approach and multi-stage sampling technique. A total of 1,152 copies of the study questionnaire will be distributed to displaced pregnant and nursing mothers (PNM); nine focus group discussions will also be held with the displaced PNM; in-depth interviews will be conducted with humanitarian actors, policymakers, and health professionals. The quantitative and qualitative data will be analysed using Statistical Package for Social Science (SPSS) 21.0 and thematic analysis, respectively. The findings of the study will be used to develop a model of care that will address the fragmentations in Nigeria's healthcare system. The findings will also inform the development of best policies and practices in the maternal health of displaced women.

Keywords: forced displacement, internally displaced women, maternal healthcare, maternal mortality

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Authors: Lia Marchi, Ernesto Antonini

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The impact of industrial sites on people’s living environment both involves detrimental effects on the ecosystem and perceptual-aesthetic interferences with the scenery. These, in turn, affect the economic and social value of the landscape, as well as the wellbeing of workers and local communities. Given the diffusion of the phenomenon and the relevance of its effects, it emerges the need for a joint approach to assess and thus mitigate the impact of factories on the landscape –being this latest assumed as the result of the action and interaction of natural and human factors. However, the impact assessment tools suitable for the purpose are quite heterogeneous and mostly monodisciplinary. On the one hand, green building rating systems (GBRSs) are increasingly used to evaluate the performance of manufacturing sites, mainly by quantitative indicators focused on environmental issues. On the other hand, methods to detect the visual and social impact of factories on the landscape are gradually emerging in the literature, but they generally adopt only qualitative gauges. The research addresses the integration of the environmental impact assessment and the perceptual-aesthetic interferences of factories on the landscape. The GBRSs model is assumed as a reference since it is adequate to simultaneously investigate different topics which affect sustainability, returning a global score. A critical analysis of GBRSs relevant to industrial facilities has led to select the U.S. GBC LEED protocol as the most suitable to the scope. A revision of LEED v4 Building Design+Construction has then been provided by including specific indicators to measure the interferences of manufacturing sites with the perceptual-aesthetic and social aspects of the territory. To this end, a new impact category was defined, namely ‘PA - Perceptual-aesthetic aspects’, comprising eight new credits which are specifically designed to assess how much the buildings are in harmony with their surroundings: these investigate, for example the morphological and chromatic harmonization of the facility with the scenery or the site receptiveness and attractiveness. The credits weighting table was consequently revised, according to the LEED points allocation system. As all LEED credits, each new PA credit is thoroughly described in a sheet setting its aim, requirements, and the available options to gauge the interference and get a score. Lastly, each credit is related to mitigation tactics, which are drawn from a catalogue of exemplary case studies, it also developed by the research. The result is a modified LEED scheme which includes compatibility with the landscape within the sustainability assessment of the industrial sites. The whole system consists of 10 evaluation categories, which contain in total 62 credits. Lastly, a test of the tool on an Italian factory was performed, allowing the comparison of three mitigation scenarios with increasing compatibility level. The study proposes a holistic and viable approach to the environmental impact assessment of factories by a tool which integrates the multiple involved aspects within a worldwide recognized rating protocol.

Keywords: environmental impact, GBRS, landscape, LEED, sustainable factory

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Authors: Chen Wang, Gerard Rowe

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The number of undergraduate engineering students enrolled in university has been increasing rapidly recently, leading to challenges associated with increased student-instructor ratios and increased diversity in academic preparedness of the entrants. An increased student-instructor ratio makes the interaction between teachers and students more difficult, with the resulting student ‘anonymity’ known to be a risk to academic success. With increasing student numbers, there is also an increasing diversity in the academic preparedness of the students at entry to university. Conceptual understanding of the entrants has been quantified via diagnostic testing, with the results for the first-year course in electrical engineering showing significant conceptual misunderstandings amongst the entry cohort. The solution is clearly multi-faceted, but part of the solution likely involves greater demands being placed on students to be masters of their own learning. In consequence, it is highly desirable that instructors help students to develop better self-regulated learning skills. A self-regulated learner is one who is capable of setting up their own learning goals, monitoring their study processes, adopting and adjusting learning strategies, and reflecting on their own study achievements. The methods by which instructors might cultivate students’ self-regulated learning abilities is receiving increasing attention from instructors and researchers. The aim of this study was to help students understand fully their self-regulated learning skill levels and provide targeted instructions to help them improve particular learning abilities in order to meet the curriculum requirements. As a survey tool, this research applied the questionnaire ‘Motivated Strategies for Learning Questionnaire’ (MSLQ) to collect first year engineering student’s self-reported data of their cognitive abilities, motivational orientations and learning strategies. MSLQ is a widely-used questionnaire for assessment of university student’s self-regulated learning skills. The questionnaire was offered online as a part of the online-scaffolding-learning tools to develop student understanding of self-regulated learning theories and learning strategies. The online tools, which have been under development since 2015, are designed to help first-year students understand their self-regulated learning skill levels by providing prompt feedback after they complete the questionnaire. In addition, the online tool also supplies corresponding learning strategies to students if they want to improve specific learning skills. A total of 866 first year engineering students who enrolled in the first-year electrical engineering course were invited to participate in this research project. By the end of the course 857 students responded and 738 of their questionnaires were considered as valid questionnaires. Analysis of these surveys showed that 66% of the students thought the online-scaffolding-learning tools helped significantly to improve their self-regulated learning abilities. It was particularly pleasing that 16.4% of the respondents thought the online-scaffolding-learning tools were extremely effective. A current thrust of our research is to investigate the relationships between students’ self-regulated learning abilities and their academic performance. Our results are being used by the course instructors as they revise the curriculum and pedagogy for this fundamental first-year engineering course, but the general principles we have identified are applicable to most first-year STEM courses.

Keywords: academic preparedness, online-scaffolding-learning tool, self-regulated learning, STEM education

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Authors: Shosh Shahrabani, Sharon Teitler-Regev, Helena Desivilya Syna, Fotini Voulgaris, Evangelos Tsoukatos, Vitor Ambrosio, Sandra M. Correia Loureiro

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International crises that affect tourism, such as terror attacks, political unrest, and economic crises have become more frequent, and their influence has become broader. The influence of such extreme events depends on their salience in the tourists' awareness. Hence, it is important to understand the mechanisms underlying tourists' selection of travel destinations, especially their perceptions of crisis-related events and the impact of the sociopolitical and economic context in their countries of origin. The current study examined how the socio-political and economic context in the home countries of potential young tourists affected their selection of travel destinations. The objective was to elucidate how the salience of various crises (economic and political) in the tourists' perceptions, due to their experiences at home, color their construal of destinations affected by similar hazards and influence their travel intentions. The study focused on student tourists from Israel, Greece, and Portugal. Today about a fifth of international tourism is based on young people, especially students. These countries were chosen since Greece and Portugal are in the midst of economic crises. In addition, Greece and Portugal have experienced political instability, while Israel has security-related problems (including terrorist incidents). In 2013, a total of 648 students, responded to a questionnaire that included questions concerning attitudes and risk perceptions regarding travel to destinations with various risk hazards as well as socio-demographic details. The results indicate that over half of the Israelis intend to visit Greece or Portugal. The majority of the Portuguese intend to visit Greece, while less than a third of them intend to visit Israel. About half of the Greeks intend to visit Portugal, and most of them do not intend to visit Israel. The results indicate that greater perceived importance of economic crises mitigates the intention to travel to destinations with economic crises for tourists from origin countries that are also marked by economic crises, such as Greece and Portugal. However, for tourists from Israel, a country with a relatively stable economy, issues related to the economy barely affect their intention to travel to the other two countries. The findings also suggest that Greeks and Portuguese who are highly concerned about political unrest are unlikely to select Israel as a tourist destination. In addition, strong apprehension regarding terrorism impedes the intention to travel to destinations marked by terrorist incidents, such as Israel. The current research contributes to the existing literature by highlighting the impact of travelers' personal previous experience with crisis on their risk perceptions and in turn on their intentions to travel to countries with similar risks. Therefore, in a world where such incidents are on the rise, understanding tourists' risk perceptions and behavior and the factors influencing their destination-related decisions are crucial for countries that wish to increase the numbers of incoming tourists.

Keywords: economic crises, political instability, risk perception, young tourists

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Authors: Pedro B. Antunes, Paulo J. Ramísio

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Road runoff is a linear source of diffuse pollution that can cause significant environmental impacts. During rainfall events, pollutants from both stationary and mobile sources, which have accumulated on the road surface, are dragged through the superficial runoff. Road runoff in coastal zones may present high levels of salinity and chlorides due to the proximity of the sea and transported marine aerosols. Appearing to be correlated to this process, organic matter concentration may also be significant. This study assesses this phenomenon with the purpose of identifying the relationships between monitored water quality parameters and intrinsic site variables. To achieve this objective, an extensive monitoring program was conducted on a Portuguese coastal highway. The study included thirty rainfall events, in different weather, traffic and salt deposition conditions in a three years period. The evaluations of various water quality parameters were carried out in over 200 samples. In addition, the meteorological, hydrological and traffic parameters were continuously measured. The salt deposition rates (SDR) were determined by means of a wet candle device, which is an innovative feature of the monitoring program. The SDR, variable throughout the year, appears to show a high correlation with wind speed and direction, but mostly with wave propagation, so that it is lower in the summer, in spite of the favorable wind direction in the case study. The distance to the sea, topography, ground obstacles and the platform altitude seems to be also relevant. It was confirmed the high salinity in the runoff, increasing the concentration of the water quality parameters analyzed, with significant amounts of seawater features. In order to estimate the correlations and patterns of different water quality parameters and variables related to weather, road section and salt deposition, the study included exploratory data analysis using different techniques (e.g. Pearson correlation coefficients, Cluster Analysis and Principal Component Analysis), confirming some specific features of the investigated road runoff. Significant correlations among pollutants were observed. Organic matter was highlighted as very dependent of salinity. Indeed, data analysis showed that some important water quality parameters could be divided into two major clusters based on their correlations to salinity (including organic matter associated parameters) and total suspended solids (including some heavy metals). Furthermore, the concentrations of the most relevant pollutants seemed to be very dependent on some meteorological variables, particularly the duration of the antecedent dry period prior to each rainfall event and the average wind speed. Based on the results of a monitoring case study, in a coastal zone, it was proven that SDR, associated with the hydrological characteristics of road runoff, can contribute for a better knowledge of the runoff characteristics, and help to estimate the specific nature of the runoff and related water quality parameters.

Keywords: coastal zones, monitoring, road runoff pollution, salt deposition

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Authors: Francisco Vidal Vázquez, Pekka Simell, Christian Frilund, Matti Reinikainen, Ilkka Hiltunen, Tim Böltken, Benjamin Andris, Paolo Piermartini

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Carbon capture and utilization (CCU) are one of the key topics in mitigation of CO2 emissions. There are many different technologies that are applied for the production of diverse chemicals from CO2 such as synthetic natural gas, Fischer-Tropsch products, methanol and polymers. Power-to-Gas and Power-to-Liquids concepts arise as a synergetic solution for storing energy and producing value added products from the intermittent renewable energy sources and CCU. VTT is a research and technology development company having energy in transition as one of the key focus areas. VTT has extensive experience in piloting and upscaling of new energy and chemical processes. Recently, VTT has developed and commissioned a Mobile Synthesis Unit (MOBSU) in close collaboration with INERATEC, a spin-off company of Karlsruhe Institute of Technology (KIT, Germany). The MOBSU is a multipurpose synthesis unit for CO2 upgrading to energy carriers and chemicals, which can be transported on-site where CO2 emission and renewable energy are available. The MOBSU is initially used for production of fuel compounds and chemical intermediates by combination of two consecutive processes: reverse Water-Gas Shift (rWGS) and Fischer-Tropsch synthesis (FT). First, CO2 is converted to CO by high-pressure rWGS and then, the CO and H2 rich effluent is used as feed for FT using an intensified reactor technology developed and designed by INERATEC. Chemical equilibrium of rWGS reaction is not affected by pressure. Nevertheless, compression would be required in between rWGS and FT in the case when rWGS is operated at atmospheric pressure. This would also require cooling of rWGS effluent, water removal and reheating. For that reason, rWGS is operated using precious metal catalyst in the MOBSU at similar pressure as FT to simplify the process. However, operating rWGS at high pressures has also some disadvantages such as methane and carbon formation, and more demanding specifications for materials. The main parts of FT module are an intensified reactor, a hot trap to condense the FT wax products, and a cold trap to condense the FT liquid products. The FT synthesis is performed using cobalt catalyst in a novel compact reactor technology with integrated highly-efficient water evaporation cooling cycle. The MOBSU started operation in November 2016. First, the FT module is tested using as feedstock H2 and CO. Subsequently, rWGS and FT modules are operated together using CO2 and H2 as feedstock of ca. 5 Nm3/hr total flowrate. On spring 2017, The MOBSU unit will be integrated together with a direct air capture (DAC) of CO2 unit, and a PEM electrolyser unit at Lappeenranta University of Technology (LUT) premises for demonstration of the SoletAir concept. This would be the first time when synthetic fuels are produced by combination of DAC unit and electrolyser unit which uses solar power for H2 production.

Keywords: CO2 utilization, demonstration, Fischer-Tropsch synthesis, intensified reactors, reverse water-gas shift

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Authors: Sadi Ali, Yaser Kishawi

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As part of Palestine, Gaza Strip (365 km2 and 1.8 million habitants) is considered a semi-arid zone relies solely on the Coastal Aquifer. The coastal aquifer is only source of water with only 5-10% suitable for human use. This barely covers the domestic and agricultural needs of Gaza Strip. Palestinian Water Authority Strategy is to find non-conventional water resource from treated wastewater to irrigate 1500 hectares and serves over 100,000 inhabitants. A new WWTP project is to replace the old-overloaded Biet Lahia WWTP. The project consists of three parts; phase A (pressure line & 9 infiltration basins - IBs), phase B (a new WWTP) and phase C (Recovery and Reuse Scheme – RRS – to capture the spreading plume). Currently, phase A is functioning since Apr 2009. Since Apr 2009, a monitoring plan is conducted to monitor the infiltration rate (I.R.) of the 9 basins. Nearly 23 million m3 of partially treated wastewater were infiltrated up to Jun 2014. It is important to maintain an acceptable rate to allow the basins to handle the coming quantities (currently 10,000 m3 are pumped an infiltrated daily). The methodology applied was to review and analysis the collected data including the I.R.s, the WW quality and the drying-wetting schedule of the basins. One of the main findings is the relation between the Total Suspended Solids (TSS) at BLWWTP and the I.R. at the basins. Since April 2009, the basins scored an average I.R. of about 2.5 m/day. Since then the records showed a decreasing pattern of the average rate until it reached the lower value of 0.42 m/day in Jun 2013. This was accompanied with an increase of TSS (mg/L) concentration at the source reaching above 200 mg/L. The reducing of TSS concentration directly improved the I.R. (by cleaning the WW source ponds at Biet Lahia WWTP site). This was reflected in an improvement in I.R. in last 6 months from 0.42 m/day to 0.66 m/day then to nearly 1.0 m/day as the average of the last 3 months of 2013. The wetting-drying scheme of the basins was observed (3 days wetting and 7 days drying) besides the rainfall rates. Despite the difficulty to apply this scheme accurately a control of flow to each basin was applied to improve the I.R. The drying-wetting system affected the I.R. of individual basins, thus affected the overall system rate which was recorded and assessed. Also the ploughing activities at the infiltration basins as well were recommended at certain times to retain a certain infiltration level. This breaks the confined clogging layer which prevents the infiltration. It is recommended to maintain proper quality of WW infiltrated to ensure an acceptable performance of IBs. The continual maintenance of settling ponds at BLWWTP, continual ploughing of basins and applying soil treatment techniques at the IBs will improve the I.R.s. When the new WWTP functions a high standard effluent quality (TSS 20mg, BOD 20 mg/l, and TN 15 mg/l) will be infiltrated, thus will enhance I.R.s of IBs due to lower organic load.

Keywords: soil aquifer treatment, recovery and reuse scheme, infiltration basins, North Gaza

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Authors: Laura Norfolk, Georgina Zimbitas, Jan Sefcik, Sarah Staniland

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Magnetite nanoparticles (MNP) have been an area of increasing research interest due to their extensive applications in industry, such as in carbon capture, water purification, and crucially, the biomedical industry. The use of MNP in the biomedical industry is rising, with studies on their effect as Magnetic resonance imaging contrast agents, drug delivery systems, and as hyperthermic cancer treatments becoming prevalent in the nanomaterial research community. Particles used for biomedical purposes must meet stringent criteria; the particles must have consistent shape and size between particles. Variation between particle morphology can drastically alter the effective surface area of the material, making it difficult to correctly dose particles that are not homogeneous. Particles of defined shape such as octahedral and cubic have been shown to outperform irregular shaped particles in some applications, leading to the need to synthesize particles of defined shape. In nature, highly homogeneous MNP are found within magnetotactic bacteria, a unique bacteria capable of producing magnetite nanoparticles internally under ambient conditions. Biomineralisation proteins control the properties of the MNPs, enhancing their homogeneity. One of these proteins, Mms6, has been successfully isolated and used in vitro as an additive in room-temperature co-precipitation reactions (RTCP) to produce particles of defined mono-dispersed size & morphology. When considering future industrial scale-up it is crucial to consider the costs and feasibility of an additive, as an additive that is not readily available or easily synthesized at a competitive price will not be sustainable. As such, additives selected for this research are inspired by the functional groups of biomineralisation proteins, but cost-effective, environmentally friendly, and compatible with scale-up. Diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), and pentaethylenehexamine (PEHA) have been successfully used in RTCP to modulate the properties of particles synthesized, leading to the formation of octahedral nanoparticles with no use of organic solvents, heating, or toxic precursors. By extending this principle to a fluidic system, ongoing research will reveal whether the amine additives can also exert morphological control in an environment which is suited toward higher particle yield. Two fluidic systems have been employed; a peristaltic turbulent flow mixing system suitable for the rapid production of MNP, and a macrofluidic system for the synthesis of tailored nanomaterials under a laminar flow regime. The presence of the amine additives in the turbulent flow system in initial results appears to offer similar morphological control as observed under RTCP conditions, with higher proportions of octahedral particles formed. This is a proof of concept which may pave the way to green synthesis of tailored MNP on an industrial scale. Mms6 and amine additives have been used in the macrofluidic system, with Mms6 allowing magnetite to be synthesized at unfavourable ferric ratios, but no longer influencing particle size. This suggests this synthetic technique while still benefiting from the addition of additives, may not allow additives to fully influence the particles formed due to the faster timescale of reaction. The amine additives have been tested at various concentrations, the results of which will be discussed in this paper.

Keywords: bioinspired, green synthesis, fluidic, magnetite, morphological control, scale-up

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Authors: Abirami Baleswaran, Christel Couderc, Loubnah Belahcen, Jean Dayde, Hélène Tormo, Gwénaëlle Jard

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Cheeses are often reported to be spoiled by Pseudomonas spp., responsible for defects in appearance, texture, taste, and smell, leading to their non-marketing and even their destruction. Despite preventive actions, problems linked to Pseudomonas spp. are difficult to control by the lack of knowledge and control of these contaminants during the cheese manufacturing. Lactic goat cheese producers are not spared by this problem and are looking for solutions to decrease the number of spoiled cheeses. To explore different hypotheses, experiments are needed. However, cheese-making experiments at the pilot scale are expensive and time consuming. Thus, there is a real need to develop a miniature cheeses model system under controlled conditions. In a previous study, several miniature cheese models corresponding to different type of commercial cheeses have been developed for different purposes. The models were, for example, used to study the influence of milk, starters cultures, pathogen inhibiting additives, enzymatic reactions, microflora, freezing process on cheese. Nevertheless, no miniature model was described on the lactic goat cheese. The aim of this work was to develop a miniature cheese model system under controlled laboratory conditions which resembles commercial lactic goat cheese to study Pseudomonas spp. spoilage during the manufacturing and ripening process. First, a protocol for the preparation of miniature cheeses (3.5 times smaller than a commercial one) was designed based on the cheese factorymanufacturing process. The process was adapted from “Rocamadour” technology and involves maturation of pasteurized milk, coagulation, removal of whey by centrifugation, moulding, and ripening in a little scale cellar. Microbiological (total bacterial count, yeast, molds) and physicochemical (pH, saltinmoisture, moisture in fat-free)analyses were performed on four key stages of the process (before salting, after salting, 1st day of ripening, and end of ripening). Factory and miniature cheeses volatilomewere also obtained after full scan Sift-MS cheese analysis. Then, Pseudomonas spp. strains isolated from contaminated cheeses were selected on their origin, their ability to produce pigments, and their enzymatic activities (proteolytic, lecithinasic, and lipolytic). Factory and miniature curds were inoculated by spotting selected strains on the cheese surface. The expression of cheese spoilage was evaluated by counting the level of Pseudomonas spp. during the ripening and by visual observation and under UVlamp. The physicochemical and microbiological compositions of miniature cheeses permitted to assess that miniature process resembles factory process. As expected, differences involatilomes were observed, probably due to the fact that miniature cheeses are made usingpasteurized milk to better control the microbiological conditions and also because the little format of cheese induced probably a difference during the ripening even if the humidity and temperature in the cellar were quite similar. The spoilage expression of Pseudomonas spp. was observed in miniature and factory cheeses. It confirms that the proposed model is suitable for the preparation of miniature cheese specimens in the spoilage study of Pseudomonas spp. in lactic cheeses. This kind of model could be deployed for other applications and other type of cheese.

Keywords: cheese, miniature, model, pseudomonas spp, spoilage

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Authors: Supriya Majumder, Pabitra Banik

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Fates of Arsenic (As) on the soil-plant environment belong to the critical emerging issue, which in turn to appraises the threatening implications of a human health risk — assessing the dynamics of As in soil solid components are likely to impose its potential availability towards plant uptake. In the present context, we introduced an improved Sequential Extraction Procedure (SEP) questioning to identify solid-phase speciation of As in paddy soil under variable soil environmental conditions during two consecutive seasons of rice cultivation practices. We coupled gradients of water management practices with the addition of fertilizer amendments to assess the changes in a partition of As through a field experimental study during monsoon and post-monsoon season using two rice cultivars. Water management regimes were varied based on the methods of cultivation of rice by Conventional (waterlogged) vis-a-vis System of Rice Intensification-SRI (saturated). Fertilizer amendment through the nutrient treatment of absolute control, NPK-RD, NPK-RD + Calcium silicate, NPK-RD + Ferrous sulfate, Farmyard manure (FYM), FYM + Calcium silicate, FYM + Ferrous sulfate, Vermicompost (VC), VC + Calcium silicate, VC + Ferrous sulfate were selected to construct the study. After harvest, soil samples were sequentially extracted to estimate partition of As among the different fractions such as: exchangeable (F1), specifically sorbed (F2), As bound to amorphous Fe oxides (F3), crystalline Fe oxides (F4), organic matter (F5) and residual phase (F6). Results showed that the major proportions of As were found in F3, F4 and F6, whereas F1 exhibited the lowest proportion of total soil As. Among the nutrient treatment mediated changes on As fractions, the application of organic manure and ferrous sulfate were significantly found to restrict the release of As from exchangeable phase. Meanwhile, conventional practice produced much higher release of As from F1 as compared to SRI, which may substantially increase the environmental risk. In contrast, SRI practice was found to retain a significantly higher proportion of As in F2, F3, and F4 phase resulting restricted mobilization of As. This was critically reflected towards rice grain As bioavailability where the reduction in grain As concentration of 33% and 55% in SRI concerning conventional treatment (p <0.05) during monsoon and post-monsoon season respectively. Also, prediction assay for rice grain As bioavailability based on the linear regression model was performed. Results demonstrated that rice grain As concentration was positively correlated with As concentration in F1 and negatively correlated with F2, F3, and F4 with a satisfactory level of variation being explained (p <0.001). Finally, we conclude that F1, F2, F3 and F4 are the major soil. As fractions critically may govern the potential availability of As in soil and suggest that rice cultivation with the SRI treatment is particularly at less risk of As availability in soil. Such exhaustive information may be useful for adopting certain management practices for rice grown in contaminated soil concerning to the environmental issues in particular.

Keywords: arsenic, fractionation, paddy soil, potential availability

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Authors: Hadi S. Hosseini, Larry A. Taber

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In the embryo, heart is initially a simple tubular structure that undergoes complex morphological changes as it transforms into a four-chambered pump. This work focuses on mechanisms that create heart tube (HT). The early embryo is composed of three relatively flat primary germ layers called endoderm, mesoderm, and ectoderm. Precardiac cells located within bilateral regions of the mesoderm called heart fields (HFs) fold and fuse along the embryonic midline to create the HT. The right and left halves of this plate fold symmetrically to bring their upper edges into contact along the midline, where they fuse. In a region near the fusion line, these layers then separate to generate the primitive HT and foregut, which then extend vertically. The anterior intestinal portal (AIP) is the opening at the caudal end of the foregut, which descends as the HT lengthens. The biomechanical mechanisms that drive this folding are poorly understood. Our central hypothesis is that folding is caused by differences in growth between the endoderm and mesoderm while subsequent extension is driven by contraction along the AIP. The feasibility of this hypothesis is examined using experiments with chick embryos and finite-element modeling (FEM). Fertilized white Leghorn chicken eggs were incubated for approximately 22-33 hours until appropriate Hamburger and Hamilton stage (HH5 to HH9) was reached. To inhibit contraction, embryos were cultured in media containing blebbistatin (myosin II inhibitor) for 18h. Three-dimensional models were created using ABAQUS (D. S. Simulia). The initial geometry consists of a flat plate including two layers representing the mesoderm and endoderm. Tissue was considered as a nonlinear elastic material with growth and contraction (negative growth) simulated using a theory, in which the total deformation gradient is given by F=F^*.G, where G is growth tensor and F* is the elastic deformation gradient tensor. In embryos exposed to blebbistatin, initial folding and AIP descension occurred normally. However, after HFs partially fused to create the upper part of the HT, fusion, and AIP descension stopped, and the HT failed to grow longer. These results suggest that cytoskeletal contraction is required only for the later stages of HT formation. In the model, a larger biaxial growth rate in the mesoderm compared to the endoderm causes the bilayered plate to bend ventrally, as the upper edge moves toward the midline, where it 'fuses' with the other half . This folding creates the upper section of the HT, as well as the foregut pocket bordered by the AIP. After this phase completes by stage HH7, contraction along the arch-shaped AIP pulls the lower edge of the plate downward, stretching the two layers. Results given by model are in reasonable agreement with experimental data for the shape of HT, as well as patterns of stress and strain. In conclusion, results of our study support our hypothesis for the creation of the heart tube.

Keywords: heart tube formation, FEM, chick embryo, biomechanics

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Authors: Lena Payati, Maria Kazou, Effie Tsakalidou

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Table olives are one of the most popular fermented vegetables worldwide, which along with olive oil, have a crucial role in the world economy. They are highly appreciated by the consumers for their characteristic taste and pleasant aromas, while several health and nutritional benefits have been reported as well. Until recently, microbial biogeography, i.e., the study of microbial diversity over time and space, has been mainly associated with wine. However, nowadays, the term 'terroir' has been extended to other crops and food products so as to link the geographical origin and environmental conditions to quality aspects of fermented foods. Taking the above into consideration, the present study focuses on the microbial fingerprinting of the most important olive varieties of Greece with the state-of-the-art amplicon-based metagenomics analysis. Towards this, in 2019, 61 samples from 38 different olive varieties were collected at the final stage of ripening from 13 well spread geographical regions in Greece. For the metagenomics analysis, total DNA was extracted from the olive samples, and the 16S rRNA gene and ITS DNA region were sequenced and analyzed using bioinformatics tools for the identification of bacterial and yeasts/fungal diversity, respectively. Furthermore, principal component analysis (PCA) was also performed for data clustering based on the average microbial composition of all samples from each region of origin. According to the composition, results obtained, when samples were analyzed separately, the majority of both bacteria (such as Pantoea, Enterobacter, Roserbergiella, and Pseudomonas) and yeasts/fungi (such as Aureobasidium, Debaromyces, Candida, and Cladosporium) genera identified were found in all 61 samples. Even though interesting differences were observed at the relative abundance level of the identified genera, the bacterial genus Pantoea and the yeast/fungi genus Aureobasidium were the dominant ones in 35 and 40 samples, respectively. Of note, olive samples collected from the same region had similar fingerprint (genera identified and relative abundance level) regardless of the variety, indicating a potential association between the relative abundance of certain taxa and the geographical region. When samples were grouped by region of origin, distinct bacterial profiles per region were observed, which was also evident from the PCA analysis. This was not the case for the yeast/fungi profiles since 10 out of the 13 regions were grouped together mainly due to the dominance of the genus Aureobasidium. A second cluster was formed for the islands Crete and Rhodes, both of which are located in the Southeast Aegean Sea. These two regions clustered together mainly due to the identification of the genus Toxicocladosporium in relatively high abundances. Finally, the Agrinio region was separated from the others as it showed a completely different microbial fingerprinting. However, due to the limited number of olive samples from some regions, a subsequent PCA analysis with more samples from these regions is expected to yield in a more clear clustering. The present study is part of a bigger project, the first of its kind in Greece, with the ultimate goal to analyze a larger set of olive samples of different varieties and from different regions in Greece in order to have a reliable olives’ microbial biogeography.

Keywords: amplicon-based metagenomics analysis, bacteria, microbial biogeography, olive microbiota, yeasts/fungi

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Authors: Mary Isobelle Mullaney

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The maxim "an unexamined life is not worth living," attributed to Socrates, prompts a contemplative reflection spanning over 32 years as a teacher educator in the Republic of Ireland. Taking time to contemplate the changes that have occurred and the current landscape provides valuable insights into the dynamic terrain of teacher preparation. The reflective journey traverses the impacts of global and societal shifts, responding to challenges, embracing advancements, and navigating the delicate balance between responsiveness to the world and the active shaping of it. The transformative events of the COVID-19 pandemic spotlighted the indispensable role of teachers in Ireland, reinforcing the critical nature of education for the well-being of pupils. Research solidifies the understanding that teachers matter and so it is worth exploring the pivotal role of the teacher educator. This reflective piece examines the changes in teacher education and explores the juxtapositions that have emerged in response to three decades of profound change. The attractiveness of teaching as a career is juxtaposed against the reality of the demands of the job, with conditions for public servants in Ireland undergoing a shift. High-level strategic discussions about increasing teacher numbers now contrast with a previous oversupply. The delicate balance between the imperative to increase enrolment (getting "bums on seats") and the gatekeeper role of teacher educators is explored, raising questions about maintaining high standards amid changing student profiles. Another poignant dichotomy involves the high demand for teachers versus the hurdles candidates face in becoming teachers. The rising cost and duration of teacher education courses raise concerns about attracting quality candidates. The perceived attractiveness of teaching as a career contends with the reality of increased demands on educators. One notable juxtaposition centres around the rapid evolution of Irish initial teacher education versus the potential risk of change overload. The Teaching Council of Ireland has spearheaded considerable changes, raising questions about the timing and evaluation of these changes. This reflection contemplates the vision of a professional teaching council versus its evolving reality and the challenges posed by the value placed on school placement in teacher preparation. The juxtapositions extend to the classroom, where theory may not seamlessly align with the lived experience. Inconsistencies between college expectations and the classroom reality prompt reflection on the effectiveness of teacher preparation programs. Addressing the changing demographic landscape of society and schools, there is a persistent incongruity between the diversity of Irish society and the profile of second-level teachers. As education undergoes a digital revolution, the enduring philosophies of education confront technological advances. This reflection highlights the tension between established practices and contemporary demands, acknowledging the irreplaceable value of face-to-face interaction while integrating technology into teacher training programs. In conclusion, this reflective journey encapsulates the intricate web of juxtapositions in Irish Initial Teacher Education. It emphasises the enduring commitment to fostering education, recognising the profound influence educators wield, and acknowledging the challenges and gratifications inherent in shaping the minds and futures of generations to come.

Keywords: Irish post primary teaching, juxtapositions, reflection, teacher education

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Authors: Beatriz Rebocho, Elisabete Valente, Carla Palma, Andreia Guilherme, Filipa Bessa, Paula Sobral

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The global accumulation of plastic in the oceans is a growing problem. Plastic is transported from its source to the oceans via rivers, which are considered the main route for plastic particles from land-based sources to the ocean. These plastics undergo physical and chemical degradation resulting in microplastics. The i-Plastic project aims to understand and predict the dispersion, accumulation and impacts of microplastics (5 mm to 1 µm) and nano plastics (below 1 µm) in marine environments from the tropical and temperate land-ocean interface to the open ocean under distinct flow and climate regimes. Seasonal monitoring of the fluxes of microplastics was carried out in (three) coastal areas in Brazil, Portugal and Spain. The present work shows the first results of in-situ seasonal monitoring and mapping of microplastics in ocean waters between Ovar and Vieira de Leiria (Portugal), in which 43 surface water samples and 43 water column samples were collected in contrasting seasons (spring and autumn). The spring and autumn surface water samples were collected with a 300 µm and 150 µm pore neuston net, respectively. In both campaigns, water column samples were collected using a conical mesh with a 150 µm pore. The experimental procedure comprises the following steps: i) sieving by a metal sieve; ii) digestion with potassium hydroxide to remove the organic matter original from the sample matrix. After a filtration step, the content is retained on a membrane and observed under a stereomicroscope, and physical and chemical characterization (type, color, size, and polymer composition) of the microparticles is performed. Results showed that 84% and 88% of the surface water and water column samples were contaminated with microplastics, respectively. Surface water samples collected during the spring campaign averaged 0.35 MP.m-3, while surface water samples collected during autumn recorded 0.39 MP.m-3. Water column samples from the spring campaign had an average of 1.46 MP.m-3, while those from the autumn recorded 2.54 MP.m-3. In the spring, all microplastics found were fibers, predominantly black and blue. In autumn, the dominant particles found in the surface waters were fibers, while in the water column, fragments were dominant. In spring, the average size of surface water particles was 888 μm, while in the water column was 1063 μm. In autumn, the average size of surface and water column microplastics was 1333 μm and 1393 μm, respectively. The main polymers identified by Attenuated Total Reflectance (ATR) and micro-ATR Fourier Transform Infrared (FTIR) spectroscopy from all samples were low-density polyethylene (LDPE), polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC). The significant difference between the microplastic concentration in the water column between the two campaigns could be due to the remixing of the water masses that occurred that week due to the occurrence of a storm. This work presents preliminary results since the i-Plastic project is still in progress. These results will contribute to the understanding of the spatial and temporal dispersion and accumulation of microplastics in this marine environment.

Keywords: microplastics, Portugal, Atlantic Ocean, water column, surface water

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Authors: Ajay Kumar Pandey

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White grub (Coleoptera: Scarabaeidae), locally known as Kurmula, Pagra, Chinchu, is a major destructive pest in western Himalayan region of Uttarakhand state of India. Various crops like cereals (up land paddy, wheat, and barley), vegetables (capsicum, cabbage, tomato, cauliflower, carrot etc) and some pulse (like pigeon pea, green gram, black gram) are grown with limited availability of primary resources. Among the various limitations in successful cultivation of these crops, white grub has been proved a major constraint in for all crops grown in hilly area. The losses incurred due to white grubs are huge in case of commercial crops like sugarcane, groundnut, potato, maize and upland rice. Moreover, it has been proved major constraint in potato production in mid and higher hills of India. Adults emerge in May-June following the onset of monsoon and thereafter defoliate the apple, apricot, plum, and walnut during night while 2nd and 3rd instar grubs feed on live roots of cultivated as well as non cultivated crops from August to January. Survey was conducted in hilly (Pauri and Tehri) as well as plain area (Haridwar district) of Uttarakhand state. Collection of beetle was done from various locations from August to September of five consecutive years with the help of light trap and directly from host plant. The grub was also collected by excavating one square meter area from different locations and reared in laboratory to find out adult. During the collection, the diseased or dead cadaver were also collected and brought in the laboratory and identified the causal organisms. Total 25 species of white grub was identified out of which Holotrichia longipennis, Anomala dimidiata, Holotrichia lineatopennis, Maladera insanabilis, Brahmina sp. make complex problem in different area of Uttarakhand where they cause severe damage to various crops. During the survey, it was observed that white grubs beetles have variation in preference of host plant, even in choice of fruit and leaves of host plant. It was observed that, a white grub species, which identified as Lepidiota mansueta Burmeister., was causing severe havoc to sugarcane crop grown in major sugarcane growing belt of Haridwar district. The study also revealed that Bacillus cereus, Beauveria bassiana, Metarhizium anisopliae, Steinernema, Heterorhabditis are major disease causing agents in immature stage of white grub under rain-fed condition of Uttarakhand which caused 15.55 to 21.63 percent natural mortality of grubs with an average of 18.91 percent. However, among the microorganisms, B. cereus found to be significantly more efficient (7.03 percent mortality) then the entomopathogenic fungi (3.80 percent mortality) and nematodes (3.20 percent mortality).

Keywords: Lepidiota, profiling, Uttarakhand, whitegrub

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Authors: Marlon Gallo, Eduardo Miguel, Laura Oca, Eneko Gonzalez, Unai Iraola

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The heat generation of an energy storage system is an essential topic when designing a battery pack and its cooling system. Heat generation estimation is used together with thermal models to predict battery temperature in operation and adapt the design of the battery pack and the cooling system to these thermal needs guaranteeing its safety and correct operation. In the present work, a comparison between the use of a heat flux sensor (HFS) for indirect measurement of heat losses in a cell and the widely used and simplified version of Bernardi’s equation for estimation is presented. First, a Li-ion cell is thermally characterized with an HFS to measure the thermal parameters that are used in a first-order lumped thermal model. These parameters are the equivalent thermal capacity and the thermal equivalent resistance of a single Li-ion cell. Static (when no current is flowing through the cell) and dynamic (making current flow through the cell) tests are conducted in which HFS is used to measure heat between the cell and the ambient, so thermal capacity and resistances respectively can be calculated. An experimental platform records current, voltage, ambient temperature, surface temperature, and HFS output voltage. Second, an equivalent circuit model is built in a Matlab-Simulink environment. This allows the comparison between the generated heat predicted by Bernardi’s equation and the HFS measurements. Data post-processing is required to extrapolate the heat generation from the HFS measurements, as the sensor records the heat released to the ambient and not the one generated within the cell. Finally, the cell temperature evolution is estimated with the lumped thermal model (using both HFS and Bernardi’s equation total heat generation) and compared towards experimental temperature data (measured with a T-type thermocouple). At the end of this work, a critical review of the results obtained and the possible mismatch reasons are reported. The results show that indirectly measuring the heat generation with HFS gives a more precise estimation than Bernardi’s simplified equation. On the one hand, when using Bernardi’s simplified equation, estimated heat generation differs from cell temperature measurements during charges at high current rates. Additionally, for low capacity cells where a small change in capacity has a great influence on the terminal voltage, the estimated heat generation shows high dependency on the State of Charge (SoC) estimation, and therefore open circuit voltage calculation (as it is SoC dependent). On the other hand, with indirect measuring the heat generation with HFS, the resulting error is a maximum of 0.28ºC in the temperature prediction, in contrast with 1.38ºC with Bernardi’s simplified equation. This illustrates the limitations of Bernardi’s simplified equation for applications where precise heat monitoring is required. For higher current rates, Bernardi’s equation estimates more heat generation and consequently, a higher predicted temperature. Bernardi´s equation accounts for no losses after cutting the charging or discharging current. However, HFS measurement shows that after cutting the current the cell continues generating heat for some time, increasing the error of Bernardi´s equation.

Keywords: lithium-ion battery, heat flux sensor, heat generation, thermal characterization

Procedia PDF Downloads 388

Authors: A. Volperts, G. Dobele, A. Zhurinsh, I. Kruusenberg, A. Plavniece, J. Locs

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Nowadays energy consumption constantly increases and development of effective and cheap electrochemical sources of power, such as fuel cells and electrochemical capacitors, is topical. Due to their high specific power, charge and discharge rates, working lifetime supercapacitor based energy accumulation systems are more and more extensively being used in mobile and stationary devices. Lignocellulosic materials are widely used as precursors and account for around 45% of the total raw materials used for the manufacture of activated carbon which is the most suitable material for supercapacitors. First part of our research is devoted to study of influence of main stages of wood thermochemical activation parameters on activated carbons porous structure formation. It was found that the main factors governing the properties of carbon materials are specific surface area, volume and pore size distribution, particles dispersity, ash content and oxygen containing groups content. Influence of activated carbons attributes on capacitance and working properties of supercapacitor are demonstrated. The correlation between activated carbons porous structure indices and electrochemical specifications of supercapacitors with electrodes made from these materials has been determined. It is shown that if synthesized activated carbons are used in supercapacitors then high specific capacitances can be reached – more than 380 F/g in 4.9M sulfuric acid based electrolytes and more than 170 F/g in 1 M tetraethylammonium tetrafluoroborate in acetonitrile electrolyte. Power specifications and minimal price of H₂-O₂ fuel cells are limited by the expensive platinum-based catalysts. The main direction in development of non-platinum catalysts for the oxygen reduction is the study of cheap porous carbonaceous materials which can be obtained by the pyrolysis of polymers including renewable biomass. It is known that nitrogen atoms in carbon materials to a high degree determine properties of the doped activated carbons, such as high electrochemical stability, hardness, electric resistance, etc. The lack of sufficient knowledge on the doping of the carbon materials calls for the ongoing researches of properties and structure of modified carbon matrix. In the second part of this study, highly porous activated carbons were synthesized using alkali thermochemical activation from wood, cellulose and cellulose production residues – craft lignin and sewage sludge. Activated carbon samples were doped with dicyandiamide and melamine for the application as fuel cell cathodes. Conditions of nitrogen introduction (solvent, treatment temperature) and its content in the carbonaceous material, as well as porous structure characteristics, such as specific surface and pore size distribution, were studied. It was found that efficiency of doping reaction depends on the elemental oxygen content in the activated carbon. Relationships between nitrogen content, porous structure characteristics and electrodes electrochemical properties are demonstrated.

Keywords: activated carbons, low-temperature fuel cells, nitrogen doping, porous structure, supercapacitors

Procedia PDF Downloads 116

Authors: Annika J. Meyer, Tom Piechotta

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Unmanned Aerial Vehicles (UAVs) have increasingly become vital tools in various applications, including surveillance, search and rescue, and environmental monitoring. One common approach to ensure redundant communication systems when flying beyond visual line of sight is for UAVs to employ multiple mobile data modems by different providers. Although widely adopted, this approach suffers from several drawbacks, such as high costs, added weight and potential increases in signal interference. In light of these challenges, this paper proposes a communication framework intermeshing mobile networks and LoRa (Long Range) technology—a low-power, long-range communication protocol. LoRaWAN (Long Range Wide Area Network) is commonly used in Internet of Things applications, relying on stationary gateways and Internet connectivity. This paper, however, utilizes the underlying LoRa protocol, taking advantage of the protocol’s low power and long-range capabilities while ensuring efficiency and reliability. Conducted in collaboration with the Potsdam Fire Department, the implementation of mobile network technology in combination with the LoRa protocol in small UAVs (take-off weight < 0.4 kg), specifically designed for search and rescue and area monitoring missions, is explored. This research aims to test the viability of LoRa as an additional redundant communication system during UAV flights as well as its intermeshing with the primary, mobile network-based controller. The methodology focuses on direct UAV-to-UAV and UAV-to-ground communications, employing different spreading factors optimized for specific operational scenarios—short-range for UAV-to-UAV interactions and long-range for UAV-to-ground commands. This explored use case also dramatically reduces one of the major drawbacks of LoRa communication systems, as a line of sight between the modules is necessary for reliable data transfer. Something that UAVs are uniquely suited to provide, especially when deployed as a swarm. Additionally, swarm deployment may enable UAVs that have lost contact with their primary network to reestablish their connection through another, better-situated UAV. The experimental setup involves multiple phases of testing, starting with controlled environments to assess basic communication capabilities and gradually advancing to complex scenarios involving multiple UAVs. Such a staged approach allows for meticulous adjustment of parameters and optimization of the communication protocols to ensure reliability and effectiveness. Furthermore, due to the close partnership with the Fire Department, the real-world applicability of the communication system is assured. The expected outcomes of this paper include a detailed analysis of LoRa's performance as a communication tool for UAVs, focusing on aspects such as signal integrity, range, and reliability under different environmental conditions. Additionally, the paper seeks to demonstrate the cost-effectiveness and operational efficiency of using a single type of communication technology that reduces UAV payload and power consumption. By shifting from traditional cellular network communications to a more robust and versatile cellular and LoRa-based system, this research has the potential to significantly enhance UAV capabilities, especially in critical applications where reliability is paramount. The success of this paper could pave the way for broader adoption of LoRa in UAV communications, setting a new standard for UAV operational communication frameworks.

Keywords: LoRa communication protocol, mobile network communication, UAV communication systems, search and rescue operations

Procedia PDF Downloads 42

Authors: D. Malouch, M. Berchel, C. Dreanno, S. Stachowski-Haberkorn, P-A. Jaffres

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Biofilm is a predominant lifestyle chosen by bacteria. Whether it is developed on an immerged surface or a mobile biofilm known as flocs, the bacteria within this form of life show properties different from its planktonic ones. Within the biofilm, the self-formed matrix of Extracellular Polymeric Substances (EPS) offers hydration, resources capture, enhanced resistance to antimicrobial agents, and allows cell-communication. Biofouling is a complex natural phenomenon that involves biological, physical and chemical properties related to the environment, the submerged surface and the living organisms involved. Bio-colonization of artificial structures can cause various economic and environmental impacts. The increase in costs associated with the over-consumption of fuel from biocolonized vessels has been widely studied. Measurement drifts from submerged sensors, as well as obstructions in heat exchangers, and deterioration of offshore structures are major difficulties that industries are dealing with. Therefore, surfaces that inhibit biocolonization are required in different areas (water treatment, marine paints, etc.) and many efforts have been devoted to produce efficient and eco-compatible antifouling agents. The different steps of surface fouling are widely described in literature. Studying the biofilm and its stages provides a better understanding of how to elaborate more efficient antifouling strategies. Several approaches are currently applied, such as the use of biocide anti-fouling paint6 (mainly with copper derivatives) and super-hydrophobic coatings. While these two processes are proving to be the most effective, they are not entirely satisfactory, especially in a context of a changing legislation. Nowadays, the challenge is to prevent biofouling with non-biocide compounds, offering a cost effective solution, but with no toxic effects on marine organisms. Since the micro-fouling phase plays an important role in the regulation of the following steps of biofilm formation7, it is desired to reduce or delate biofouling of a given surface by inhibiting the micro fouling at its early stages. In our recent works, we reported that some amphiphilic compounds exhibited bacteriostatic or bactericidal properties at a concentration that did not affect eukaryotic cells. These remarkable properties invited us to assess this type of bio-inspired phospholipids9 to prevent the colonization of surfaces by marine bacteria. Of note, other studies reported that amphiphilic compounds interacted with bacteria leading to a reduction of their development. An amphiphilic compound is a molecule consisting of a hydrophobic domain and a polar head (ionic or non-ionic). These compounds appear to have interesting antifouling properties: some ionic compounds have shown antimicrobial activity, and zwitterions can reduce nonspecific adsorption of proteins. Herein, we investigate the potential of amphiphilic compounds as inhibitors of bacterial growth and marine biofilm formation. The aim of this study is to compare the efficacy of four synthetic phospholipids that features a cationic charge (BSV36, KLN47) or a zwitterionic polar-head group (SL386, MB2871) to prevent microfouling with marine bacteria. We also study the toxicity of these compounds in order to identify the most promising compound that must feature high anti-adhesive properties and a low cytotoxicity on two links representative of coastal marine food webs: phytoplankton and oyster larvae.

Keywords: amphiphilic phospholipids, bacterial biofilm, marine microfouling, non-toxic antifouling

Procedia PDF Downloads 145

Authors: Michel Pons, Anthony Delahaye, Laurence Fournaison

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Secondary refrigeration consists of splitting large-size direct-cooling units into volume-limited primary cooling units complemented by secondary loops for transporting and distributing cold. Such a design reduces the refrigerant leaks, which represents a source of greenhouse gases emitted into the atmosphere. However, inserting the secondary circuit between the primary unit and the ‘users’ heat exchangers (UHX) increases the energy consumption of the whole process, which induces an indirect emission of greenhouse gases. It is thus important to check whether that efficiency loss is sufficiently limited for the change to be globally beneficial to the environment. Among the likely secondary fluids, phase change slurries offer several advantages: they transport latent heat, they stabilize the heat exchange temperature, and the formerly evaporators still can be used as UHX. The temperature level can also be adapted to the desired cooling application. Herein, the slurry {ice in mono-propylene-glycol solution} (melting temperature Tₘ of 6°C) is considered for food preservation, and the slurry {mixed hydrate of CO₂ + tetra-n-butyl-phosphonium-bromide in aqueous solution of this salt + CO₂} (melting temperature Tₘ of 13°C) is considered for air conditioning. For the sake of thermodynamic consistency, the analysis encompasses the whole process, primary cooling unit plus secondary slurry loop, and the various properties of the slurries, including their non-Newtonian viscosity. The design of the whole process is optimized according to the properties of the chosen slurry and under explicit constraints. As a first constraint, all the units must deliver the same cooling power to the user. The other constraints concern the heat exchanges areas, which are prescribed, and the flow conditions, which prevent deposition of the solid particles transported in the slurry, and their agglomeration. Minimization of the total energy consumption leads to the optimal design. In addition, the results are analyzed in terms of exergy losses, which allows highlighting the couplings between the primary unit and the secondary loop. One important difference between the ice-slurry and the mixed-hydrate one is the presence of gaseous carbon dioxide in the latter case. When the mixed-hydrate crystals melt in the UHX, CO₂ vapor is generated at a rate that depends on the phase change kinetics. The flow in the UHX, and its heat and mass transfer properties are significantly modified. This effect has never been investigated before. Lastly, inserting the secondary loop between the primary unit and the users increases the temperature difference between the refrigerated space and the evaporator. This results in a loss of global energy efficiency, and therefore in an increased energy consumption. The analysis shows that this loss of efficiency is not critical in the first case (Tₘ = 6°C), while the second case leads to more ambiguous results, partially because of the higher melting temperature.The consequences in terms of greenhouse gases emissions are also analyzed.

Keywords: exergy, hydrates, optimization, phase change material, thermodynamics

Procedia PDF Downloads 129

Authors: A. M. Plante, F. O’Halloran, A. L. McCarthy

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By 2050 it is projected that 2 billion of the global population will be more than 60 years old. Older adults have unique dietary requirements and aging is associated with physiological changes that affect appetite, sensory perception, metabolism, and digestion. Therefore, it is essential that foods recommended and designed for older adults promote healthy aging. To assess cheese as a functional food for the elderly, a range of commercial cheese products were selected and compared for their antioxidant properties. Cheese from various milk sources (bovine, goats, sheep) with different textures and fat content, including cheddar, feta, goats, brie, roquefort, halloumi, wensleydale and gouda, were initially digested with two different simulated in vitro gastrointestinal digestion (SGID) models. One SGID model represented a validated in vitro adult digestion system and the second model, an elderly SGID, was designed to consider the physiological changes associated with aging. The antioxidant potential of all cheese digestates was investigated using in vitro chemical-based antioxidant assays, (2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP) and total phenolic content (TPC)). All adult model digestates had high antioxidant activity across both DPPH ( > 70%) and FRAP ( > 700 µM Fe²⁺/kg.fw) assays. Following in vitro digestion using the elderly SGID model, full-fat red cheddar, low-fat white cheddar, roquefort, halloumi, wensleydale, and gouda digestates had significantly lower (p ≤ 0.05) DPPH radical scavenging properties compared to the adult model digestates. Full-fat white cheddar had higher DPPH radical scavenging activity following elderly SGID digestion compared to the adult model digestate, but the difference was not significant. All other cheese digestates from the elderly model were comparable to the digestates from the adult model in terms of radical scavenging activity. The FRAP of all elderly digestates were significantly lower (p ≤ 0.05) compared to the adult digestates. Goats cheese was significantly higher (p ≤ 0.05) in FRAP (718 µM Fe²/kg.fw) compared to all other digestates in the elderly model. TPC levels in the soft cheeses (feta, goats) and low-fat cheeses (red cheddar, white cheddar) were significantly lower (p ≤ 0.05) in the elderly digestates compared to the adult digestates. There was no significant difference in TPC levels, between the elderly and adult model for full-fat cheddar (red, white), roquefort, wensleydale, gouda, and brie digestates. Halloumi cheese was the only cheese that was significantly higher in TPC levels following elderly digestion compared to adult digestates. Low fat red cheddar had significantly higher (p ≤ 0.05) TPC levels compared to all other digestates for both adult and elderly digestive systems. Findings from this study demonstrate that aging has an impact on the bioactivity of cheese, as antioxidant activity and TPC levels were lower, following in vitro elderly digestion compared to the adult model. For older adults, soft cheese, particularly goats cheese, was associated with high radical scavenging and reducing power, while roquefort cheese had low antioxidant activity. Also, elderly digestates of halloumi and low-fat red cheddar were associated with high TPC levels. Cheese has potential as a functional food for the elderly, however, bioactivity can vary depending on the cheese matrix. Funding for this research was provided by the RISAM Scholarship Scheme, Cork Institute of Technology, Ireland.

Keywords: antioxidants, cheese, in-vitro digestion, older adults

Procedia PDF Downloads 225