Search results for: free movement of persons
1133 Determination of Friction and Damping Coefficients of Folded Cover Mechanism Deployed by Torsion Springs
Authors: I. Yilmaz, O. Taga, F. Kosar, O. Keles
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In this study, friction and damping coefficients of folded cover mechanism were obtained in accordance with experimental studies and data. Friction and damping coefficients are the most important inputs to accomplish a mechanism analysis. Friction and damping are two objects that change the time of deployment of mechanisms and their dynamic behaviors. Though recommended friction coefficient values exist in literature, damping is differentiating feature according to mechanic systems. So the damping coefficient should be obtained from mechanism test outputs. In this study, the folded cover mechanism use torsion springs for deploying covers that are formerly close folded position. Torsion springs provide folded covers with desirable deploying time according to variable environmental conditions. To verify all design revisions with system tests will be so costly so that some decisions are taken in accordance with numerical methods. In this study, there are two folded covers required to deploy simultaneously. Scotch-yoke and crank-rod mechanisms were combined to deploy folded covers simultaneously. The mechanism was unlocked with a pyrotechnic bolt onto scotch-yoke disc. When pyrotechnic bolt was exploded, torsion springs provided rotational movement for mechanism. Quick motion camera was recording dynamic behaviors of system during deployment case. Dynamic model of mechanism was modeled as rigid body with Adams MBD (multi body dynamics) then torque values provided by torsion springs were used as an input. A well-advised range of friction and damping coefficients were defined in Adams DOE (design of experiment) then a large number of analyses were performed until deployment time of folded covers run in with test data observed in record of quick motion camera, thus the deployment time of mechanism and dynamic behaviors were obtained. Same mechanism was tested with different torsion springs and torque values then outputs were compared with numerical models. According to comparison, it was understood that friction and damping coefficients obtained in this study can be used safely when studying on folded objects required to deploy simultaneously. In addition to model generated with Adams as rigid body the finite element model of folded mechanism was generated with Abaqus then the outputs of rigid body model and finite element model was compared. Finally, the reasonable solutions were suggested about different outputs of these solution methods.Keywords: damping, friction, pyro-technic, scotch-yoke
Procedia PDF Downloads 3221132 Between the Pen and the Dish Towel: Paradox of Globalization
Authors: Sandra Maria Cerqueira Da Silva
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In Brazil, women are the majority of the country's population. They have advanced in terms of years of education and professional training. However, this has not prevented the differences in the labor market from being sustained, particularly the wage gap and inequalities concerning the access to command positions and promotions, i.e., in the gender relations and treatment. One of the conditions which constitute a barrier to career advancement is the necessary support chain to support women when they are in the labor market. Therefore, the purpose of this research is to demonstrate, describe, and criticize some of the current conformations of support chains and how these compete to promote the phenomenon known as glass ceiling in the country. However, this support may come even from inside a woman's own home, with a fairer division of household activities between men and women. Such behavior can free an entire network of women within the same family. In addition, it can serve as pressure to structure better conditions for women as a whole, improving the living conditions of the poor population. This can occur through programs and projects for qualification and retraining of adult women. In answer to the question that guides this study, it is concluded that a family support system is critical to the success of women in management positions. To meet this demand, one of the ways could be the development of specific gender policies by the public authorities, in accordance with the emerging global economic policies, in order to provide and structure the necessary support. This would respond to feminist manifestations - which should go on pointing needs – although the legislative assembly should also propose ideas to change this picture. This is a qualitative research, with a poststructuralist approach, featuring a cutout corpus of three interviews carried out with women holding leadership positions in the academia. Questions related to this very discussion are many. New studies could address points as the promotion of qualification and expansion of skills of women in subaltern condition. There is also need to investigate possible support systems, considering the inequalities and local economic conditions.Keywords: gender and labor market, glass ceiling, post-structuralism, support chain
Procedia PDF Downloads 2331131 The Impact of Centralisation on Radical Prostatectomy Outcomes: Our Outcomes
Authors: Jemini Vyas, Oluwatobi Adeyoe, Jenny Branagan, Chandran Tanabalan, John Beatty, Aakash Pai
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Introduction: The development of robotic surgery has accelerated centralisation to tertiary centres, where robotic radical prostatectomy (RP) is offered. The purpose of concentrating treatment in high volume specialist centres is to improve the quality of care and patient outcomes. The aim of this study was to assess the impact on clinical outcomes of centralisation for locally diagnosed patients undergoing RP. Methods: Clinical outcomes for 169 consecutive laparoscopic & open RP pre-centralisation were retrospectively compared with 50 consecutive robotic RP conducted over a similar period post-centralisation. Preoperative risk stratification and time to surgery were collected. Perioperative outcomes, including length of stay (LOS) and complications, were collated. Post-operative outcomes, including erectile dysfunction (ED), biochemical recurrence (BCR), and urinary continence, were assessed. Results: Preoperative risk stratification showed no difference between the two groups. The median time from diagnosis to treatment was similar between the two groups (pre-centralisation, 121 days, post-centralisation, 117 days). The mean length of stay (pre-centralisation, 2.1 days, post-centralisation, 1.6 days) showed no significant difference (p=0.073). Proportion of overall complications (pre-centralisation, 11.4%, post-centralisation, 8.7%) and complications, above Clavien-Dindo 2, were similar between the two groups (pre-centralisation1.2%, post-centralisation 2.2%). Post operative functional parameters, including continence and ED, were comparable. Five-year BCR free rate was 78% for the pre-centralisation group and 79% for the post centralisation group. Conclusion: For our cohort of patients, clinical outcomes have remained static during centralisation. It is imperative that centralisation is accompanied by increased capacity, streamlining of pathways, and training to ensure that improved quality of care is achieved. Our institution has newly acquired a robot, and prospectively studying this data may support the reversal of centralisation for RP surgery.Keywords: prostate, cancer, prostatectomy, clinical
Procedia PDF Downloads 941130 Evaluation of Total Phenolic Content and Antioxidant Activity in Amaranth Seeds Grown in Latvia
Authors: Alla Mariseva, Ilze Beitane
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Daily intake of products rich in antioxidants that scavenge free radicals in cell membranes is an effective way to combat oxidative stress. Last year there was noticed higher interest towards the identification and utilization of plants rich in antioxidant compounds as they may behave as preventive medicine. Amaranth seeds due to polyphenols, anthocyanins, flavonoids, and tocopherols are characterized by high antioxidant activity. The study aimed to evaluate the total phenolic content and radical scavenging activity of amaranth seeds cultivated in 2020 in two farms in Latvia. One sample of amaranth seeds came from an organic farm, the other – from a conventional farm. The total phenol content of amaranth seed extracts was measured with the Folin-Ciocalte spectrophotometric method. The total phenols were expressed as gallic acid equivalents (GAE) per 100 g dry weight (DW) of the samples. The antioxidant activity of amaranth seed extracts was calculated based on scavenging activities of the stable 2.2-diphenyl-1-picrylhydrazyl (DPPH˙) radical, the radical scavenging capacity (ABTS) was demonstrated as Trolox mM equivalents (TE) per 100 g-1 dry weight. Three parallel measurements were performed on all samples. There were significant differences between organic and conventional amaranth seeds in terms of total phenolic content and antioxidant activity. Organic amaranth seeds showed higher total phenolic content compared to conventional amaranth seeds, 65.4±6.0 mg GAE 100 g⁻¹ DW and 43.4±7.8 mg GAE 100 g⁻¹ DW respectively. Organic amaranth seeds were also characterized by higher DPPH radical scavenging activity (7.9±0.4 mM TE 100 g⁻¹ of dry matter) and ABTS radical scavenging capacity (13.2±1.5 mM TE 100 g⁻¹ of dry matter). The results obtained on total phenolic content and antioxidant activity of amaranth seeds grown in Latvia confirmed that the samples have a high biological value; therefore, it would be necessary to promote their consumption by including them in various food products, including vegan products, increasing their nutritional value.Keywords: ABTS, amaranth seeds, antioxidant activity, DPPH, total phenolic content
Procedia PDF Downloads 2211129 The Impact of Brand Hate and Love: A Thematic Analysis of Online Emotions in Response to Disney’s Corporate Activism
Authors: Roxana D. Maiorescu-Murphy
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Companies have recently embraced political activism as an alleged responsibility toward the communities they operate in. As a result of its recency, there is little understanding of the impact of corporate activism on consumers. In addition, embracing corporate activism engenders polarizing opinions, potentially leading to a crisis of morality shown in past literature to flourish in online settings. The present study contributes to the literature on communication management, which currently lacks research on stakeholder perceptions toward corporate activism in general and from the perspective of the stakeholders’ emotions of brand hate versus a love that they display before a specific corporate act of activism. For this purpose, the study analyzed online reactions on Twitter following Disney’s stance against Florida’s House Bill 1577 enacted in April 2022. Dubbed the “Don’t Say Gay Bill” by the left wing and the “Parental Rights Bill” by the conservative movement, the legislation triggered polarizing opinions in society and among Disney’s stakeholders, as the company announce it was taking action against it. Given the scarcity of research on corporate political activism and crises of morality, the current study enacted the case study methodology. Consequently, it answered to the research questions of how online stakeholders responded to Disney’s stance as well as why they formed such an opinion. The data were collected from Twitter over a seven-day period of analysis, namely from March 28- April 3, 2022. The period of analysis started on the day Disney announced its stance (March 28, 2022) until the reactions to its announcement petered out significantly (April 3, 2022). The final sample of analysis consisted of N=1,344 and represented Twitter comments in response to the company’s political announcement. The data were analyzed using the grounded theory methodology, which implied multiple exposures to the text and the undertaking of an inductive-deductive approach that led to the emergence of several recurrent themes. The findings revealed that the stakeholders’ prior emotions toward the company (brand hate versus brand love) did not play a greater role in their (dis)agreement with the latter’s activism than the users’ political stances. Specifically, whether they despised or hated Disney prior to this incident was less significant than their personal political stances. Above all, users were more inclined to transition from brand love to brand hate and vice versa based on the political side they viewed Disney to fall under.Keywords: corporate political advocacy, crisis management, brand hate, brand love
Procedia PDF Downloads 1191128 The Characteristics of Porcine Immune Synapse via Flow Cytometry and Transmission Electron Microscope
Authors: Ann Ying-An Chen, Yi-Lun Tsai, Hso-Chi Chaung
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An understanding of pathogens and the immune system has played an utmost important role in agricultural research for the development of vaccinations. The immunological synapse, cell to cell interaction play a crucial role in triggering the body's immune system, such as activation between antigen-presenting cells (APCs) and different subsets of T-cell. If these interactions are regulated appropriately, the host has the ability to defend itself against a wide spectrum of infectious pathogens. The aim of this study is to establish and to characterize a porcine immune synapse system by co-culturing T cell/APC. In this study, blood samples were collected from specific-pathogen-free piglets, and peripheral blood mononuclear cells (PBMC) were separated by using Ficoll-Pague. The PBMC were then stained with CD4 (FITC) and CD25 (PE) antibodies. Different subsets of T cells sorted by fluorescence-activated cell sorting flow cytometer were co-cultured for 24 hrs with alveolar macrophages, and the profiles of cytokine secretion and mRNA transcription levels of Toll-like receptors were examined after. Results showed that the three stages of immune synapse were clearly visible and identified under both transmission and scanning electron microscope (TEM and SEM). The significant interaction differences in toll-like receptor expressions within the co-cultured cell system were observed. The TLR7 mRNA expressions in CD4+CD25- cells were lower than those in CD4+CD25+ and CD4 -CD25+. Interestingly, the IL-10 production levels in CD4+CD25- cells (7.732 pg/mL) were significantly higher than those of CD4+CD25+ (2.636 pg/mL) and CD4 -CD25+ (2.48 pg/mL). These findings demonstrated that a clear understanding of the porcine immune synapse system can contribute greatly for further investigations on the mechanism of T-cell activation, which can benefit in the discovery of potential adjuvant candidate or effective antigen epitopes in the development of vaccinations with high efficacy.Keywords: antigen-presenting cells, immune synapse, pig, T subsets, toll-like receptor
Procedia PDF Downloads 1271127 The Importance of a Coating and Architecture of the Surface Metal on the Survival of Uncemented Total Knee Arthroplasty
Authors: Raymond Puijk, Rachid Rassir, Inger N. Sierevelt, Anneke Spekenbrink-Sporen, Bart G. C. W. Pijls, Rob G. H. H. Nelissen, Peter A. Nolte
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Background: Among uncemented total knee arthroplasty (TKA), a wide variety of metal surface structures (MSS) and coatings exist to enhance implants' biological properties (i.e., bone ingrowth). This study explores the variety of MSS-coating combinations and compares their mid-long-term survivorships with cemented TKAs, by using data from the Dutch Arthroplasty Register. Methods: A total of 235,500 cemented and 11,132 uncemented primary TKAs with a median follow-up of 5.1 years were included. MSS-coating combinations were (1) Porous-uncoated (n=8986), (2) Beaded-hydroxyapatite (HA)(n=1093), (3) Matte-uncoated (n=846), (4) Matte-Titanium-nitride (TiN) (n=207). Five- and 10-year revision-free survival for all-cause revisions, and aseptic loosening of the tibial component, were calculated and compared by using Kaplan-Meier, Log-rank tests, and multivariable Cox proportional hazard regression analyses. Results: Ten-year survival rates with all-cause revisions as an endpoint, were 94.2% for cement, and 94.7%, 96.3%, 92.1%, and 79.0% for porous-uncoated, beaded-HA, matte-uncoated, and Matte-TiN, respectively (p<0.01). Rates for aseptic loosening were 98.8% for cemented, and 98.7%, 99.8%, 97.2%, and 94.9% for the uncemented, respectively (p<0.01).The beaded-HA implants were half the risk for an all-cause revision compared to cemented implants (p<0.01). Matte-uncoated and matte-TiN implants were at more risk of an all-cause revision than cemented implants (p=0.01, p<0.01). Proportions of revisions for aseptic loosening were comparable among most groups. Conclusion: Based on Dutch registry data, four main MSS-coating combinations among uncemented TKAs were found. survivorships for all-cause revisions and aseptic release differed widely between groups. Beaded-HA and porous-uncoated implants had the best survival rates among the uncemented TKAs and were non-inferior to the cemented TKAs.Keywords: total knee arthroplasty, cement, uncemented, cementless;, metal surface structure, coating
Procedia PDF Downloads 1521126 The Effect of Addition of White Mulberry Fruits on the Antioxidant Activity of the New Developed Bioactive Bread
Authors: Kobus-Cisowska Joanna, Flaczyk Ewa, Gramza-Michalowska Anna, Kmiecik Dominik, Przeor Monika, Marcinkowska Agata, Korczak Józef
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Cereal products, including mainly bread is a staple food known from the beginning of history throughout the world. It is now believed that there is no replacement of the basic food. Bread, due to the high content of starch is the energy source for the proper functioning of our body. It also contains proteins, fats, vitamins, especially of the B group and vitamin E, a number of minerals, and fiber. The aim of the study was to evaluate the antioxidant activity of new developed bread premixes with mulberry fruits for people with anemia, diabetes, obesity and cardiovascular disease. From the finished product-bread, aqueous and methanol extracts was prepared, which in next step were analyzed to assess the activity of the radical DPPH test, ABTS, chelating activity, the ability to reduce metals. Extracts were prepared from bread were acquired with premixes directly after production and stored for three months. The resulting trial breads effect by different mechanisms of antioxidant. They showed the ability to scavenge radicals ABTS and DPPH and chelating activity. Methanol extracts showed significantly greater antioxidant activity in comparison with aqueous extracts, and the largest effect was estimated for sample of bread for anemia, diabetes and cardiovascular disease. The greatest ability to scavenging ABTS radicals showed breads for anemia, diabetes and cardiovascular disease, while smaller for anemia and control sample. It was shown that the methanol extracts of the breads samples showed no ability to chelate iron (II). These properties are observed only in the aqueous extracts. The greatest ability attempt had anemia while the lowest control sample. Financial supported by the UE Project no POIG 01.01.02-00-061/09.Keywords: morus alba, antioxidant activity, free radicals, polyphenols
Procedia PDF Downloads 3111125 Secondary True to Life Polyethylene Terephthalate Nanoplastics: Obtention, Characterization, and Hazard Evaluation
Authors: Aliro Villacorta, Laura Rubio, Mohamed Alaraby, Montserrat López Mesas, Victor Fuentes-Cebrian, Oscar H. Moriones, Ricard Marcos, Alba Hernández.
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Micro and nano plastics (MNPLs) are emergent environmental pollutants requiring urgent information on their potential risks to human health. One of the problems associated with the evaluation of their undesirable effects is the lack of real samples matching those resulting from the environmental degradation of plastic wastes. To such end, we propose an easy method to obtain polyethylene terephthalate nano plastics from water plastic bottles (PET-NPLs) but, in principle, applicable to any other plastic goods sources. An extensive characterization indicates that the proposed process produces uniform samples of PET-NPLs of around 100 nm, as determined by using a multi-angle and dynamic light scattering methodology. An important point to be highlighted is that to avoid the metal contamination resulting from methods using metal blades/burrs for milling, trituration, or sanding, we propose to use diamond burrs to produce metal-free samples. To visualize the toxicological profile of the produced PET-NPLs, we have evaluated their ability to be internalized by cells, their cytotoxicity, and their ability to induce oxidative stress and induce DNA damage. In this preliminary approach, we have detected their cellular uptake, but without the induction of significant biological effects. Thus, no relevant increases in toxicity, reactive oxygen species (ROS) induction, or DNA damage -as detected with the comet assay- have been observed. The use of real samples, as produced in this study, will generate relevant data in the discussion about the potential health risks associated with MNPLs exposures.Keywords: nanoplastics, polyethylene terephthalate, physicochemical characterization, cell uptake, cytotoxicity
Procedia PDF Downloads 971124 Effect of a Nutritional Supplement Containing Euterpe oleracea Mart., Inulin, Phaseolus vulgaris and Caralluma fimbriata in Persons with Metabolic Syndrome
Authors: Eduardo Cabrera-Rode, Janet Rodriguez, Aimee Alvarez, Ragmila Echevarria, Antonio D. Reyes, Ileana Cubas-Duenas, Silvia E. Turcios, Oscar Diaz-Diaz
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Obex is a nutritional supplement to help weight loss naturally. In addition, this supplement has a satiating effect that helps control the craving to eat between meals. The purpose of this study was to evaluate the effect of Obex in the metabolic syndrome (MS). This was an open label pilot study conducted in 30 patients with MS and ages between 29 and 60 years old. Participants received Obex, at a dose of one sachet before (30 to 45 minutes) the two main meals (lunch and dinner) daily (mean two sachets per day) for 3 months. The content of the sachets was dissolved in a glass of water or fruit juice. Obex ingredients: Açai (Euterpe oleracea Mart.) berry, inulin, Phaseolus vulgaris, Caralluma fimbriata, inositol, choline, arginine, ornitine, zinc sulfate, carnitine fumarate, methionine, calcium pantothenate, pyridoxine and folic acid. In addition to anthropometric measures and blood pressure, fasting plasma glucose, total cholesterol, triglycerides and HDL-cholesterol and insulin were determined. Insulin resistance was assessed by HOMA-IR index. Three indirect indexes were used to calculate insulin sensitivity [QUICKI index (Quantitative insulin sensitivity check index), Bennett index and Raynaud index]. Metabolic syndrome was defined according to the Joint Interim Statement (JIS) criteria. The JIS criteria require at least three of the following components: (1) abdominal obesity (waist circumference major or equal major or equal 94 cm for men or 80 cm for women), (2) triglycerides major or equal 1.7 mmol/L, (3) HDL cholesterol minor 1.03 mmol/L for men or minor 1.30 mmol/L for women, (4) systolic/diastolic blood pressure major or equal 130/85mmHg or use antihypertensive drugs, and (5) fasting plasma glucose major or equal 5.6 mmol/L or known treatment for diabetes. This study was approved by the Ethical and Research Committee of the National Institute of Endocrinology, Cuba and conducted according to the Declaration of Helsinki. Obex is registered as a food supplement in the National Institute of Nutrition and Food, Havana, Cuba. Written consent was obtained from all patients before the study. The clinical trial had been registered at ClinicalTrials.gov. After three months of treatment, 43.3% (13/30) of participants decreased the frequency of MS. Compared to baseline, Obex significantly reduced body weight, BMI, waist circumference, and waist/hip ratio and improved HDL-c (p<0.0001) and in addition to lowering blood pressure (p<0.05). After Obex intake, subjects also have shown a reduction in fasting plasma glucose (p<0.0001) and insulin sensitivity was enhanced (p=0.001). No adverse effects were seen in any of the participants during the study. In this pilot study, consumption of Obex decreased the prevalence of MS due to the improved selected components of the metabolic syndrome, indicating that further studies are warranted. Obex emerges as an effective and well tolerated treatment for preventing or delaying MS and therefore potential reduction of cardiovascular risk.Keywords: nutritional supplement, metabolic syndrome, weight loss, insulin resistance
Procedia PDF Downloads 2981123 Vitamin D Levels of Patients with Rheumatoid Arthritis in Kosova
Authors: Mjellma Rexhepi, Blerta Rexhepi Kelmendi, Blana Krasniqi, Shaip Krasniqi
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Rheumatoid arthritis is a chronic disease that causes inflammation of the joints which can be so severe that can cause not only deformities but also impairment of function that limits movement. This also contributes to the pain that accompanies this disease. This remains a problematic and challenging disease of modern medicine because treatment is still symptomatic. The main purpose of drug treatment is to reduce the activity of the disease, achieve remission, avoid disability and death. The etiology of the disease is idiopathic, but can also be linked to genetic, nongenetic factors such as hormonal, environmental or infectious. Current scientific evidence shows that vitamin D plays an important role in immune regulation mechanisms. Lack of this vitamin has been linked to loss of immune tolerance and the appearance of autoimmune processes, including rheumatoid arthritis. The purpose of the work was to define Vitamin D in patients hospitalized with rheumatoid arthritis in University Clinical Center of Kosova, as a basis of their connection with lifestyle and physical inactivity. The sample for the work was selected from patients with criteria met for rheumatoid arthritis who were hospitalized at the tertiary level of health care in Kosova. During the work have been investigated 100 consecutive patients fulfilling diagnostic criteria for rheumatoid arthritis, whereas in addition to the general characteristics are also determined the values of vitamin D at the beginning of hospitalization. The average age of the sample analyzed was 50.9±5.7 years old, with an average duration of rheumatoid arthritis disease 7.8±3.4 years. At the beginning of hospitalization, before treatment was initiated, the average value of vitamin D was 15.86±3.43, which according to current reference values is classified into the category of insufficient values. Correlating the duration of the disease, from the time of diagnosis to the day of hospitalization, on one side and the level of vitamin D on the other side, the negative correlation of a lower degree derived (r =-0.1). Physical activity affects the concentration of vitamin D in the blood through increased metabolism of fat and the release of vitamin D and its metabolites from adipose tissue. To now it is evident that physical activity is also accompanied by higher levels of vitamin D. In patients with rheumatoid arthritis, vitamin D levels were low compared to normal. Future works should be oriented toward investigating in detail the bone structure, quality of life and pain in patients with rheumatoid arthritis. More detailed scientific projects, with larger numbers of participants, should be designed for the future to clarify more possible mechanisms as factors related to this phenomenon such as inactivity, lifestyle and the duration of the disease, as well as the importance of keeping vitamin D values at normal limits.Keywords: hospitalization, lifestyle, rheumatoid arthritis, vitamin D
Procedia PDF Downloads 151122 Preparation of β-Polyvinylidene Fluoride Film for Self-Charging Lithium-Ion Battery
Authors: Nursultan Turdakyn, Alisher Medeubayev, Didar Meiramov, Zhibek Bekezhankyzy, Desmond Adair, Gulnur Kalimuldina
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In recent years the development of sustainable energy sources is getting extensive research interest due to the ever-growing demand for energy. As an alternative energy source to power small electronic devices, ambient energy harvesting from vibration or human body motion is considered a potential candidate. Despite the enormous progress in the field of battery research in terms of safety, lifecycle and energy density in about three decades, it has not reached the level to conveniently power wearable electronic devices such as smartwatches, bands, hearing aids, etc. For this reason, the development of self-charging power units with excellent flexibility and integrated energy harvesting and storage is crucial. Self-powering is a key idea that makes it possible for the system to operate sustainably, which is now getting more acceptance in many fields in the area of sensor networks, the internet of things (IoT) and implantable in-vivo medical devices. For solving this energy harvesting issue, the self-powering nanogenerators (NGS) were proposed and proved their high effectiveness. Usually, sustainable power is delivered through energy harvesting and storage devices by connecting them to the power management circuit; as for energy storage, the Li-ion battery (LIB) is one of the most effective technologies. Through the movement of Li ions under the driving of an externally applied voltage source, the electrochemical reactions generate the anode and cathode, storing the electrical energy as the chemical energy. In this paper, we present a simultaneous process of converting the mechanical energy into chemical energy in a way that NG and LIB are combined as an all-in-one power system. The electrospinning method was used as an initial step for the development of such a system with a β-PVDF separator. The obtained film showed promising voltage output at different stress frequencies. X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) analysis showed a high percentage of β phase of PVDF polymer material. Moreover, it was found that the addition of 1 wt.% of BTO (Barium Titanate) results in higher quality fibers. When comparing pure PVDF solution with 20 wt.% content and the one with BTO added the latter was more viscous. Hence, the sample was electrospun uniformly without any beads. Lastly, to test the sensor application of such film, a particular testing device has been developed. With this device, the force of a finger tap can be applied at different frequencies so that electrical signal generation is validated.Keywords: electrospinning, nanogenerators, piezoelectric PVDF, self-charging li-ion batteries
Procedia PDF Downloads 1621121 Wheat Dihaploid and Somaclonal Lines Screening for Resistance to P. nodorum
Authors: Lidia Kowalska, Edward Arseniuk
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Glume and leaf blotch is a disease of wheat caused by necrotrophic fungus Parastagonospora nodorum. It is a serious pathogen in many wheat-growing areas throughout the world. Use of resistant cultivars is the most effective and economical means to control the above-mentioned disease. Plant breeders and pathologists have worked intensively to incorporate resistance to the pathogen in new cultivars. Conventional methods of breeding for resistance can be supported by using the biotechnological ones, i.e., somatic embryogenesis and androgenesis. Therefore, an effort was undertaken to compare genetic variation in P. nodorum resistance among winter wheat somaclones, dihaploids and conventional varieties. For the purpose, a population of 16 somaclonal and 4 dihaploid wheat lines from six crosses were used to assess their resistance to P. nodorum under field conditions. Lines were grown in disease-free (fungicide protected) and inoculated micro plots in 2 replications of a split-plot design in a single environment. The plant leaves were inoculated with a mixture of P. nodorum isolates three times. Spore concentrations were adjusted to 4 x 10⁶ of viable spores per one milliliter. The disease severity was rated on a scale, where > 90% – susceptible, < 10% - resistant. Disease ratings of plant leaves showed statistically significant differences among all lines tested. Higher resistance to P. nodorum was observed more often on leaves of somaclonal lines than on dihaploid ones. On average, disease, severity reached 15% on leaves of somaclones and 30% on leaves of dihaploids. Some of the genotypes were showing low leaf infection, e.g. dihaploid D-33 (disease severity 4%) and a somaclone S-1 (disease severity 2%). The results from this study prove that dihaploid and somaclonal variation might be successfully used as an additional source of wheat resistance to the pathogen and it could be recommended to use in commercial breeding programs. The reported results prove that biotechnological methods may effectively be used in breeding for disease resistance of wheat to fungal necrotrophic pathogens.Keywords: glume and leaf blotch, somaclonal, androgenic variation, wheat, resistance breeding
Procedia PDF Downloads 1201120 The Reasons for Vegetarianism in Estonia and its Effects to Body Composition
Authors: Ülle Parm, Kata Pedamäe, Jaak Jürimäe, Evelin Lätt, Aivar Orav, Anna-Liisa Tamm
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Vegetarianism has gained popularity across the world. It`s being chosen for multiple reasons, but among Estonians, these have remained unknown. Previously, attention to bone health and probable nutrient deficiency of vegetarians has been paid and in vegetarians lower body mass index (BMI) and blood cholesterol level has been found but the results are inconclusive. The goal was to explain reasons for choosing vegetarian diet in Estonia and impact of vegetarianism to body composition – BMI, fat percentage (fat%), fat mass (FM), and fat free mass (FFM). The study group comprised of 68 vegetarians and 103 omnivorous. The determining body composition with DXA (Hologic) was concluded in 2013. Body mass (medical electronic scale, A&D Instruments, Abingdon, UK) and height (Martin metal anthropometer to the nearest 0.1 cm) were measured and BMI calculated (kg/m2). General data (physical activity level included) was collected with questionnaires. The main reasons why vegetarianism was chosen were the healthiness of the vegetarian diet (59%) and the wish to fight for animal rights (72%) Food additives were consumed by less than half of vegetarians, more often by men. Vegetarians had lower BMI than omnivores, especially amongst men. Based on BMI classification, vegetarians were less obese than omnivores. However, there were no differences in the FM, FFM and fat percentage figures of the two groups. Higher BMI might be the cause of higher physical activity level among omnivores compared with vegetarians. For classifying people as underweight, normal weight, overweight and obese both BMI and fat% criteria were used. By BMI classification in comparison with fat%, more people in the normal weight group were considered; by using fat% in comparison with BMI classification, however, more people categorized as overweight. It can be concluded that the main reasons for vegetarianism chosen in Estonia are healthiness of the vegetarian diet and the wish to fight for animal rights and vegetarian diet has no effect on body fat percentage, FM and FFM.Keywords: body composition, body fat percentage, body mass index, vegetarianism
Procedia PDF Downloads 4161119 Development of Strategy for Enhanced Production of Industrial Enzymes by Microscopic Fungi in Submerged Fermentation
Authors: Zhanara Suleimenova, Raushan Blieva, Aigerim Zhakipbekova, Inkar Tapenbayeva, Zhanar Narmuratova
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Green processes are based on innovative technologies that do not negatively affect the environment. Industrial enzymes originated from biological systems can effectively contribute to sustainable development through being isolated from microorganisms which are fermented using primarily renewable resources. Many widespread microorganisms secrete a significant amount of biocatalysts into the environment, which greatly facilitates the task of their isolation and purification. The ability to control the enzyme production through the regulation of their biosynthesis and the selection of nutrient media and cultivation conditions allows not only to increase the yield of enzymes but also to obtain enzymes with certain properties. In this regard, large potentialities are embedded in immobilized cells. Enzyme production technology in a secreted active form enabling industrial application on an economically feasible scale has been developed. This method is based on the immobilization of enzyme producers on a solid career. Immobilizing has a range of advantages: decreasing the price of the final product, absence of foreign substances, controlled process of enzyme-genesis, the ability of various enzymes' simultaneous production, etc. Design of proposed equipment gives the opportunity to increase the activity of immobilized cell culture filtrate comparing to free cells, growing in periodic culture conditions. Such technology allows giving a 10-times raise in culture productivity, to prolong the process of fungi cultivation and periods of active culture liquid generation. Also, it gives the way to improve the quality of filtrates (to make them more clear) and exclude time-consuming processes of recharging fermentative vials, that require manual removing of mycelium.Keywords: industrial enzymes, immobilization, submerged fermentation, microscopic fungi
Procedia PDF Downloads 1411118 Profile of Serological Response of Equids Naturally Infected with Burkholderia mallei
Authors: Iahtasham Khan, Vania Lucia De Assis Santana, Marcilia Maria Alves De Souza, Mabel Hanna Vance Harrop, Fernando Leandro Dos Santos, Cecília Maria Souza Leão E. Silva, Pedro Paulo Silveira, Marcelo Brasil, Marcus Vinícius, Hélio Cordeiro Manso Filho, Muhammad Younus, Aman Ullah Khan
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Glanders ranks high on clinical lists in some regions of Brazil as a cause of respiratory and lymphatic disease in equids. Glanders is caused by Burkolderia mallei (B. mallei) Gram-negative bacterium. B. mallei was first biological agent used in World War I in 20th century. The complement fixation test (CFT) is a serodiagnostic tool prescribed by the World Organization for Animal Health (OIE)for the diagnosis of glanders in the international trade of equids. The aim of the present study was to monitor the serological responses in equines naturally infected with B. mallei using the CFT. A total of 574 equids were tested with CFT, 30 days apart in a total of 12 samplings. One hundred thirty-four sera tested negative in all samplings; 192 sera tested positive in one sampling and 125 sera tested positive in two or more samplings. Remaining 123 samples showed uncertain results. Thus, CFT results can vary over a period of time. These variations could be the consequence of the effects of the natural immune response in each animal. The findings of the present study demonstrate difficulties regarding the simultaneous implementation of CFT and test and slaughter policies to eradicate glanders. Another constraint to control this disease is the presence of carrier/transitory CFT-negative animals, which are a potential source of disease in glanders-free areas. Serodiagnostic tests of higher sensitivity and specificity like immunobloat should be implemented to achieve success in the eradication of glanders.Keywords: glanders, equids, horses, immunological, mules
Procedia PDF Downloads 4151117 Rationale of Eye Pupillary Diameter for the UV Protection for Sunglasses
Authors: Liliane Ventura, Mauro Masili
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Ultraviolet (UV) protection is critical for sunglasses, and mydriasis, as well as miosis, are relevant parameters to consider. The literature reports that for sunglasses, ultraviolet protection is critical because sunglasses can cause the opposite effect if the lenses do not provide adequate UV protection due to the greater dilation of the pupil when wearing sunglasses. However, the scientific literature does not properly quantify to support this rationale. The reasoning may be misleading by ignoring not only the inherent absorption of UV by the sunglass lens materials but also by ignoring the absorption of the anterior structures of the eye, i.e., the cornea and aqueous humor. Therefore, we estimate the pupil diameter and calculate the solar ultraviolet influx through the pupil of the human eye for two situations of an individual wearing and not wearing sunglasses. We quantify the dilation of the pupil as a function of the luminance of the surrounding. Therefore, we calculate the influx of solar UV through the pupil of the eye for two situations for an individual wearing sunglass and for the eyes free of shade. A typical boundary condition for the calculation is an individual in an upright position wearing sunglasses, staring at the horizon as if the sun is in the zenith. The calculation was done for the latitude of the geographic center of the state of São Paulo (-22º04'11.8'' S) from sunrise to sunset. A model from the literature is used for determining the sky luminance. The initial approach is to obtain pupil diameter as a function of luminance. Therefore, as a preliminary result, we calculate the pupil diameter as a function of the time of day, as the sun moves, for a particular day of the year. The working range for luminance is daylight (10⁻⁴ – 10⁵ cd/m²). We are able to show how the pupil adjusts to brightness change (~2 - ~7.8 mm). At noon, with the sun higher, the direct incidence of light on the pupil is lower if compared to mid-morning or mid-afternoon, when the sun strikes more directly into the eye. Thus, the pupil is larger at midday. As expected, the two situations have opposite behaviors since higher luminance implies a smaller pupil. With these results, we can progress in the short term to obtain the transmittance spectra of sunglasses samples and quantify how light attenuation provided by the spectacles affects pupil diameter.Keywords: sunglasses, UV protection, pupil diameter, solar irradiance, luminance
Procedia PDF Downloads 811116 The Role of Financial and Non-Financial Institutions in Promoting Entrepreneurship in Micro small and Medium Enterprises
Authors: Lemuel David
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The importance of the Micro, Small, and Medium Enterprises sector is well recognized for its legitimate contribution to the Macroeconomic objectives of the Republic of Liberia, like generation of employment, input t, exports, and enhancing entrepreneurship. Right now, Medium and Small enterprises accounts for about 99 percent of the industrial units in the country, contributing 60 percent of the manufacturing sector output and approximately one-third of the nation’s exports. The role of various financial institutions like ECO bank and Non-financial Institutions like Bearch Limited support promoting the growth of Micro, Small, and Medium Enterprises is unique. A small enterprise or entrepreneur gets many types of assistance from different institutions for varied purposes in the course of his entrepreneurial journey. This paper focuses on the factors related to financial institutional support and non-financial institutional support entrepreneurs to the growth of Medium and Small enterprises in the Republic of Liberia. The significance of this paper is to support Policy and Institutional Support for Medium and Small enterprises to know the views of entrepreneurs about financial and non-financial support systems in the Republic of Liberia. This study was carried out through a survey method, with the use of questionnaires. The population for this study consisted of all registered Medium and Small enterprises which have been registered during the years 2004-2014 in the republic of Liberia. The sampling method employed for this study was a simple random technique and determined a sample size of 400. Data for the study was collected using a standard questionnaire. The questionnaire consisted of two parts: the first part consisted of questions on the profile of the respondents. The second part covers (1) financial, promotional factors and (2) non-financial promotional factors. The results of the study are based on financial and non-financial supporting activities provided by institutions to Medium and Small enterprises. After investigation, it has been found that there is no difference in the support given by Financial Institutions and non-financial Institutions. Entrepreneurs perceived “collateral-free schemes and physical infrastructure support factors are highest contributing to entry and growth of Medium and Small enterprises.Keywords: micro, small, and medium enterprises financial institutions, entrepreneurship
Procedia PDF Downloads 981115 A Low Cost Gain-Coupled Distributed Feedback Laser Based on Periodic Surface p-Contacts
Authors: Yongyi Chen, Li Qin, Peng Jia, Yongqiang Ning, Yun Liu, Lijun Wang
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The distributed feedback (DFB) lasers are indispensable in optical phase array (OPA) used for light detection and ranging (LIDAR) techniques, laser communication systems and integrated optics, thanks to their stable single longitudinal mode and narrow linewidth properties. Traditional index-coupled (IC) DFB lasers with uniform gratings have an inherent problem of lasing two degenerated modes. Phase shifts are usually required to eliminate the mode degeneration, making the grating structure complex and expensive. High-quality antireflection (AR) coatings on both lasing facets are also essential owing to the random facet phases introduced by the chip cleavage process, which means half of the lasing energy is wasted. Gain-coupled DFB (GC-DFB) lasers based on the periodic gain (or loss) are announced to have single longitudinal mode as well as capable of the unsymmetrical coating to increase lasing power and efficiency thanks to facet immunity. However, expensive and time-consuming technologies such as epitaxial regrowth and nanoscale grating processing are still required just as IC-DFB lasers, preventing them from practical applications and commercial markets. In this research, we propose a low-cost, single-mode regrowth-free GC-DFB laser based on periodic surface p-contacts. The gain coupling effect is achieved simply by periodic current distribution in the quantum well caused by periodic surface p-contacts, introducing very little index-coupling effect that can be omitted. It is prepared by i-line lithography, without nanoscale grating fabrication or secondary epitaxy. Due to easy fabrication techniques, it provides a method to fabricate practical low cost GC-DFB lasers for widespread practical applications.Keywords: DFB laser, gain-coupled, low cost, periodic p-contacts
Procedia PDF Downloads 1281114 Implications of Oxidative Stress for Monoterpenoid Oxindole Alkaloid Production in Uncaria tomentosa Cultures
Authors: Ana C. Ramos Valdivia, Ileana Vera-Reyes, Ariana A. Huerta-Heredia
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The conditions of biotic and abiotic stress in plants can lead to the generation of high amounts of reactive oxygen species (ROS), which leads through a signaling cascade and second messengers to different antioxidant defense responses including the production of secondary metabolites. A limited number of species of plants like Uncaria tomentosa (cat claw) typical of the Amazon region produce monoterpenoid oxindole alkaloids (MOA) such as isopteropodine, mitraphylline, rhynchophylline and its isomers. Moreover, in cultivated roots, the glucoindole alkaloid 3α-dihydrocadambine (DHC) is also accumulated. Several studies have demonstrated that MAO has antioxidant properties and possess important pharmacological activities such as antitumor and immunostimulant while DHC, has hypotensive and hypolipidemic effects. In order the study the regulatory concerns operating in MAO production, the links between oxidative stress and antioxidant alkaloid production in U. tomentosa root cultures were examined. Different amount of hydrogen peroxide between 0.2 -1.0 mM was added to 12 days old roots cultures showing that, this substance had a differential effect on the production of DHC and MOA whereas the viability remained in 80% after six days. Addition of 0.2 mM hydrogen peroxide increased approximately 65% MAO and DHC production (0,540 ± 0.018 and 0.618 ± 0.029 mg per g dry weight, respectively) relative to the control. On contrast, after the addition of 0.6 mM and 1 mM hydrogen peroxide, DHC accumulation into the roots gradually decreased to 53% and 93% respectively, without changes in MAO concentration, which was in relation to a twice increase of the intracellular hydrogen peroxide content. On the other hand, concentrations of DHC (0.1, 0.5 and 1.0 mM in methanol) demonstrated free-radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The calculated IC50 for all tested concentrations was 0.180 mg per ml (0.33 mM) while the calculated TE50 was 276 minutes. Our results suggest that U. tomentosa root cultures both MAO and DHC have antioxidant capacities and respond to oxidative stress with a stimulation of their production; however, in presence of a higher concentration of ROS into the roots, DHC could be oxidized.Keywords: monoterpenoid indole alkaloid, oxidative stress, root cultures, uncaria tomentosa
Procedia PDF Downloads 1821113 Effect of Germination on Nutritional Values of Isolates from Two Varieties (DAS and BS) of Under-Utilized Nigerian Cultivated Solojo Cowpea (Vigna Unguiculata L. Walp)
Authors: Henry O. Chibudike, Olubamike A. Adeyoju, Bolanle O. Oluwole, Kayode O. Adebowale, Bamidele I. Olu-Owolabi, Chinedum E. Chibudike
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Studies on the Mineral Content of Solojo Flour and Protein Isolates from the two varieties (DAS and BS) of Nigeria cultivated solojo cowpeas were conducted to determine their nutritional value. These inorganic elements or minerals were classified into 3 categories: the ultra-trace minerals, which are the third category; the microelements, also known as the trace minerals, in the second category; while the first category is the macro elements, also known as major minerals. Some of the macro-elements are Ca, P, Na and Cl; the second category, micro-elements include iron, copper, cobalt, potassium, magnesium, iodine, zinc, manganese, molybdenum, F, Cr, Se and S. Results show that the proportion of Sodium (Na) which is ingested into the body in the form of NaCl through food intake maintenance of body pH and to retain water ranged from 728.97 to 253.37 ppm (72.90 to 25.34 mg/100 g); 715.24 to 235.45 ppm; 735.28 to 270.37 ppm; 726.59 to 264.35ppm, for FFDAS, FFBS, DAS and BS respectively with all values of the germinated samples all bellow the control. While FFDAS iron content ranged from 4.25 to 13.50 mg/100 g; FFBS ranged from 3.15 to 12.56 mg/100 g; DAS ranged from 3.81 to 12.90 mg/100g; BS ranged from 3.42 to 9.40 mg/100 g. The values of the germinated flours were all greater than the ungerminated flour. Iron helps to transport oxygen round the body and also helps in red blood cells building and to convert food into needed energy by the body. While Manganese an element that is needed in micro quantity but necessary to convert food into energy, is also crucial for healthy bone and cartilage creation. Results also show that zinc quantity increased as germination proceeded, and the values ranged from 38.80 ppm to 230.00 ppm (3.880 mg/100 g to 23.00 mg/100 g; 0.003880% to 0.0230%); 40.84 to 250.01 ppm; 32.85 to 93.41 ppm; 37.07 to 115.00 ppm, for FFDAS, FFBS, DAS and BS respectively. The Ca content improved significantly (p<0.05) with sprouting; the value extended from 250.56 ppm to 760.03 ppm (25.056 to 76.00 mg/100g or 0.0251 to 0.0760 %); 400.40 to 998.22 ppm; 116.87 to 195.69 ppm; 113.48 to 220.75 ppm, for FFDAS, FFBS, DAS and BS respectively. Zinc element although needed at the micro level in the body, is essential for a strong immune system to keep the body in good health. It is also crucial for the maintenance of a healthy sense of taste and odor, while Calcium is critical for strong bones and teeth, blood coagulation, and muscle tightening and relaxation. Magnesium is needed to build enzymes and antioxidants and also for healthy bones, while Potassium is needed to maintain water balance, muscle movement, and nerve impulses. It functions in conjunction with Na to regulate blood pressure.Keywords: Solojo cowpea, underutilized legumes, protein isolates, BS, DAS, ungerminated
Procedia PDF Downloads 581112 The Impact of Barefoot versus Shod Running on Lower Limb Gait Cycle Pattern among Recreational Club Runners in Durban, South Africa
Authors: Siyabonga Kunene, Calvin Shipley
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Introduction: Despite health benefits that come with running, injuries are common with prevalence ranging between 18.2% and 92.4% worldwide. Differences in gait patterns between barefoot and shod running, can determine traits that could lead to running injuries. The aim was to assess and compare lower limb gait cycle patterns between barefoot and shod running among runners. Methods: An experimental same-subject study design was used. The study population consisted of male and female adult recreational runners who were injury free from a running club in Durban. A convenience sampling method was used and 14 participants were recruited. The study was conducted in the physiotherapy performance laboratory at the University of KwaZulu-Natal. A Woodway Desmo Treadmill and KinePro gait analysis system were used. Descriptive & inferential statistics were analysed using Microsoft Excel and Intercooled Stata. Results: Participants included a greater percentage of females (57.1%, n = 8) than males (42.9%, n = 6). The mean population age was 38.57. A significant difference (p < 0.0009) between barefoot cadence (177.9236steps/min) and shod cadence (171.9445steps/min) was observed. Right (0.261s) and left (0.257s) barefoot stand phase was shorter than right (0.273s) and left (0.270s) shod stand phase. Right barefoot swing phase exhibited less significant (0.420s) results when compared to right shod swing phase (0.427s), whereas left barefoot swing phase was quicker (0.416s) than left shod swing phase (0.432s). Significant differences between barefoot and shod stand (p < 0.009) and swing (p < 0.040) phase symmetry occurred. Conclusion: A considerable difference was found between barefoot and shod running gait cycle patterns among participants. This difference may play a role in prevention of running related injuries.Keywords: barefoot running, shod running, gait cycle pattern, same-subject study design
Procedia PDF Downloads 2511111 The Inverse Problem in Energy Beam Processes Using Discrete Adjoint Optimization
Authors: Aitor Bilbao, Dragos Axinte, John Billingham
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The inverse problem in Energy Beam (EB) Processes consists of defining the control parameters, in particular the 2D beam path (position and orientation of the beam as a function of time), to arrive at a prescribed solution (freeform surface). This inverse problem is well understood for conventional machining, because the cutting tool geometry is well defined and the material removal is a time independent process. In contrast, EB machining is achieved through the local interaction of a beam of particular characteristics (e.g. energy distribution), which leads to a surface-dependent removal rate. Furthermore, EB machining is a time-dependent process in which not only the beam varies with the dwell time, but any acceleration/deceleration of the machine/beam delivery system, when performing raster paths will influence the actual geometry of the surface to be generated. Two different EB processes, Abrasive Water Machining (AWJM) and Pulsed Laser Ablation (PLA), are studied. Even though they are considered as independent different technologies, both can be described as time-dependent processes. AWJM can be considered as a continuous process and the etched material depends on the feed speed of the jet at each instant during the process. On the other hand, PLA processes are usually defined as discrete systems and the total removed material is calculated by the summation of the different pulses shot during the process. The overlapping of these shots depends on the feed speed and the frequency between two consecutive shots. However, if the feed speed is sufficiently slow compared with the frequency, then consecutive shots are close enough and the behaviour can be similar to a continuous process. Using this approximation a generic continuous model can be described for both processes. The inverse problem is usually solved for this kind of process by simply controlling dwell time in proportion to the required depth of milling at each single pixel on the surface using a linear model of the process. However, this approach does not always lead to the good solution since linear models are only valid when shallow surfaces are etched. The solution of the inverse problem is improved by using a discrete adjoint optimization algorithm. Moreover, the calculation of the Jacobian matrix consumes less computation time than finite difference approaches. The influence of the dynamics of the machine on the actual movement of the jet is also important and should be taken into account. When the parameters of the controller are not known or cannot be changed, a simple approximation is used for the choice of the slope of a step profile. Several experimental tests are performed for both technologies to show the usefulness of this approach.Keywords: abrasive waterjet machining, energy beam processes, inverse problem, pulsed laser ablation
Procedia PDF Downloads 2751110 Phytochemical Exploration of Plectranthus stocksii Hook. F. for Antioxidant and Cytotoxic Properties
Authors: Kasipandi Muniyandi, Parimelazhagan Thangaraj
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Plants are important prospective wealth of a country, combination of local health care information about a specific plant together with data published by several groups of scientists, can help in deciding whether it should be considered acceptable for medicinal use. In the developed countries, too, plant-derived drugs may be of importance. The wide variety of ailments that are being treated with Plectranthus is an indication of the medicinal value of the genus. A number of species are not toxic and so may be taken orally, whilst others are used topically on the skin or as enemas. This study was designed to evaluate the different properties of Plectranthus stocksii and the aerial parts were collected and extracted with petroleum ether, chloroform, ethyl acetate, acetone and methanol by Soxhlet apparatus and finally macerated with hot water. The quantification assays revealed that, leaf methanol extract showed higher total phenolic (415.41 mg GAE/ g extract) and tannin (177.53 mg GAE/ g extract) contents whereas leaf ethyl acetate exhibited higher flavonoids (777.11 mg RE/ g extract) content. The antioxidant efficiency of the extracts was analyzed by various radical scavenging assays. Among the different antioxidant assays, leaf ethyl acetate extract showed higher free radical scavenging activities against DPPH (IC50 = 3.46 µg/mL), ABTS (27417.65 µM TE/ g extract), FRAP (152.17 mM Fe(II)E/ mg extract) NO• radical (21.46%) and Superoxide radical (IC50 = 24.16 µg/mL) assays. All the parts P. stocksii extracts showed significant protection against OH• induced DNA damage at 50 µg concentration. The HPLC analysis of leaf ethyl acetate extract revealed the presence of Quercetin (30.29 µg/mg of extract) was the major compound. Anticancer activity of leaf ethyl acetate extract showed better IC50 values were 48.87 and 36.08 µg/ mL against MCF-7 and Caco-2 respectively. From this study, P. stocksii can act as a potent antioxidant and cytotoxic antimicrobial agent. The scope for drug development from this plant is endless and there is undoubtedly a call for further research in pharmaceutical industries.Keywords: antioxidant, cytotoxicity, phenolics, plectranthus stocksii
Procedia PDF Downloads 3831109 Two-Dimensional Material-Based Negative Differential Resistance Device with High Peak-to- Valley Current Ratio for Multi-Valued Logic Circuits
Authors: Kwan-Ho Kim, Jin-Hong Park
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The multi-valued logic (MVL) circuits, which can handle more than two logic states, are one of the promising solutions to overcome the bit density limitations of conventional binary logic systems. Recently, tunneling devices such as Esaki diode and resonant tunneling diode (RTD) have been extensively explored to construct the MVL circuits. These tunneling devices present a negative differential resistance (NDR) phenomenon in which a current decreases as a voltage increases in a specific applied voltage region. Due to this non-monotonic current behavior, the tunneling devices have more than two threshold voltages, consequently enabling construction of MVL circuits. Recently, the emergence of two dimensional (2D) van der Waals (vdW) crystals has opened up the possibility to fabricate such tunneling devices easily. Owing to the defect-free surface of the 2D crystals, a very abrupt junction interface could be formed through a simple stacking process, which subsequently allowed the implementation of a high-performance tunneling device. Here, we report a vdW heterostructure based tunneling device with multiple threshold voltages, which was fabricated with black phosphorus (BP) and hafnium diselenide (HfSe₂). First, we exfoliated BP on the SiO₂ substrate and then transferred HfSe₂ on BP using dry transfer method. The BP and HfSe₂ form type-Ⅲ heterojunction so that the highly doped n+/p+ interface can be easily implemented without additional electrical or chemical doping process. Owing to high natural doping at the junction, record high peak to valley ratio (PVCR) of 16 was observed to the best our knowledge in 2D materials based NDR device. Furthermore, based on this, we first demonstrate the feasibility of the ternary latch by connecting two multi-threshold voltage devices in series.Keywords: two dimensional van der Waals crystal, multi-valued logic, negative differential resistnace, tunneling device
Procedia PDF Downloads 2131108 Bioaccessible Phenolics, Phenolic Bioaccessibilities and Antioxidant Activities of Cookies Supplemented with Pumpkin Flour
Authors: Emine Aydin, Duygu Gocmen
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In this study, pumpkin flours (PFs) were used to replace wheat flour in cookie formulation at three different levels (10%, 20% and 30% w/w). For this purpose PFs produced by two different applications (with or without metabisulfite pre-treatment) and then dried in freeze dryer. Control sample included no PFs. The total phenolic contents of the cookies supplemented with PFs were higher than that of control and gradually increased in total phenolic contents of cookies with increasing PF supplementation levels. Phenolic content makes also significant contribution on nutritional excellence of the developed cookies. Pre-treatment with metabisulfite (MS) had a positive effect on free, bound and total phenolics of cookies which are supplemented with various levels of MS-PF. This is due to a protective effect of metabisulfite pretreatment for phenolic compounds in the pumpkin flour. Phenolic antioxidants may act and absorb in a different way in humans and thus their antioxidant and health effects will be changed accordingly. In the present study phenolics’ bioavailability of cookies was investigated in order to assess PF as sources of accessible phenolics. The content of bioaccessible phenolics and phenolic bioaccessibility of cookies supplemented with PFs had higher than those of control sample. Cookies enriched with 30% MS-PF had the highest bioaccessible phenolics (597.86 mg GAE 100g-1) and phenolic bioaccessibility (41.71%). MS application in PF production caused a significant increase in phenolic bioaccessibility of cookies. According to all assay (ABTS, CUPRAC, FRAP and DPPH), antioxidant activities of cookies with PFs higher than that of control cookie. It was also observed that the cookies supplemented with MS-PF had significantly higher antioxidant activities than those of cookies including PF. In presented study, antioxidative bioaccessibilities of cookies were also determined. The cookies with PFs had significantly (p ≤ 0.05) higher antioxidative bioaccessibilities than control ones. Increasing PFs levels enhanced antioxidative bioaccessibilities of cookies. As a result, PFs addition improved the nutritional and functional properties of cookie by causing increase in antioxidant activity, total phenolic content, bioaccessible phenolics and phenolic bioaccessibilities.Keywords: phenolic compounds, antioxidant activity, dietary fiber, pumpkin, freeze drying, cookie
Procedia PDF Downloads 2581107 Determination of the Cooling Rate Dependency of High Entropy Alloys Using a High-Temperature Drop-on-Demand Droplet Generator
Authors: Saeedeh Imani Moqadam, Ilya Bobrov, Jérémy Epp, Nils Ellendt, Lutz Mädler
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High entropy alloys (HEAs), having adjustable properties and enhanced stability compared with intermetallic compounds, are solid solution alloys that contain more than five principal elements with almost equal atomic percentage. The concept of producing such alloys pave the way for developing advanced materials with unique properties. However, the synthesis of such alloys may require advanced processes with high cooling rates depending on which alloy elements are used. In this study, the micro spheres of different diameters of HEAs were generated via a drop-on-demand droplet generator and subsequently solidified during free-fall in an argon atmosphere. Such droplet generators can generate individual droplets with high reproducibility regarding droplet diameter, trajectory and cooling while avoiding any interparticle momentum or thermal coupling. Metallography as well as X-ray diffraction investigations for each diameter of the generated metallic droplets where then carried out to obtain information about the microstructural state. To calculate the cooling rate of the droplets, a droplet cooling model was developed and validated using model alloys such as CuSn%6 and AlCu%4.5 for which a correlation of secondary dendrite arm spacing (SDAS) and cooling rate is well-known. Droplets were generated from these alloys and their SDAS was determined using quantitative metallography. The cooling rate was then determined from the SDAS and used to validate the cooling rates obtained from the droplet cooling model. The application of that model on the HEA then leads to the cooling rate dependency and hence to the identification of process windows for the synthesis of these alloys. These process windows were then compared with cooling rates obtained in processes such as powder production, spray forming, selective laser melting and casting to predict if a synthesis is possible with these processes.Keywords: cooling rate, drop-on-demand, high entropy alloys, microstructure, single droplet generation, X-ray Diffractometry
Procedia PDF Downloads 2111106 Osteoarticular Manifestations and Abnormalities of Bone Metabolism in Celiac Disease
Authors: Soumaya Mrabet, Imen Akkari, Amira Atig, Elhem Ben Jazia
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Introduction: Celiac disease (CD) is a chronic autoimmune inflammatory enteropathy caused by gluten. The clinical presentation is very variable. Malabsorption in the MC is responsible for an alteration of the bone metabolism. Our purpose is to study the osteoarticular manifestations related to this condition. Material and methods: It is a retrospective study of 41 cases of CD diagnosed on clinical, immunological, endoscopic and histological arguments, in the Internal Medicine and Gastroenterology Department of Farhat Hached Hospital between September 2005 and January 2016. Results: Osteoarticular manifestations were found in 9 patients (22%) among 41 patients presenting CD. These were 7 women and 2 men with an average age of 35.7 years (25 to 67 years). These manifestations were revelatory of CD in 3 cases. Abdominal pain and diarrhea were present in 6 cases. Inflammatory polyarthralgia of wrists and knees has been reported in 7 patients. Mechanical mono arthralgia was noted in 2 patients. Biological tests revealed microcytic anemia by iron deficiency in 7 cases, hypocalcemia in 5 cases, Hypophosphatemia in 3 cases and elevated alkaline phosphatases in 3 cases. Upper gastrointestinal endoscopy with duodenal biopsy found villous atrophy in all cases. In immunology, Anti-transglutaminase antibodies were positive in all patients, Anti-endomysium in 7 cases. Measurement of bone mineral density (BMD) by biphotonic X-ray absorptiometer with evaluation of the T-score and the Z-score was performed in Twenty patients (48.8%). It was normal in 7 cases (33%) and showed osteopenia in 5 patients (25%) and osteoporosis in 2 patients (10%). All patients were treated with a Gluten-free diet associated with vitamin D and calcium substitution in 5 cases. The evolution was favorable in all cases with reduction of bone pain and normalization of the phosphocalcic balance. Conclusion: The bone impact of CD is frequent but often asymptomatic. Patients with CD should be evaluated by the measurement of bone mineral density and monitored for calcium and vitamin D deficiencies.Keywords: bone mineral density, celiac disease, osteoarticular manifestations, vitamin D and calcium
Procedia PDF Downloads 3281105 Formulation and Evaluation of Metformin Hydrochloride Microparticles via BÜCHI Nano-Spray Dryer B-90
Authors: Tamer Shehata
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Recently, nanotechnology acquired a great interest in the field of pharmaceutical production. Several pharmaceutical equipment were introduced into the research field for production of nanoparticles, among them, BÜCHI’ fourth generation nano-spray dryer B-90. B-90 is specialized with single step of production and drying of nano and microparticles. Currently, our research group is investigating several pharmaceutical formulations utilizing BÜCHI Nano-Spray Dryer B-90 technology. One of our projects is the formulation and evaluation of metformin hydrochloride mucoadhesive microparticles for treatment of type 2-diabetis. Several polymers were investigated, among them, gelatin and sodium alginate. The previous polymers are natural polymers with mucoadhesive properties. Preformulation studies such as atomization head mesh size, flow rate, head temperature, polymer solution viscosity and surface tension were performed. Postformulation characters such as particle size, flowability, surface scan and dissolution profile were evaluated. Finally, the pharmacological activity of certain selected formula was evaluated in streptozotocin-induced diabetic rats. B-90’spray head was 7 µm hole heated to 120 with air flow rate 3.5 mL/min. The viscosity of the solution was less than 11.5 cP with surface tension less than 70.1 dyne/cm. Successfully, discrete, non-aggregated particles and free flowing powders with particle size was less than 2000 nm were obtained. Gelatin and Sodium alginate combination in ratio 1:3 were successfully sustained the in vitro release profile of the drug. Hypoglycemic evaluation of the previous formula showed a significant reduction of blood glucose level over 24 h. In conclusion, mucoadhesive metformin hydrochloride microparticles obtained from B-90 could offer a convenient dosage form with enhanced hypoglycemic activity.Keywords: mucoadhesive, microparticles, metformin hydrochloride, nano-spray dryer
Procedia PDF Downloads 3111104 Appraisal of Oxidative Stress in Pregnant and Non-Pregnant Non Descript Goat from Arid Tracts in India
Authors: Sudha Summarwar, Sudesh Agarwal, Deepali Lall, Nalini Kataria, Jyotsana Pandey
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Assessment of antioxidant status is an effective tool to appraise the presence of oxidative stress. A combination of assays can be used to evaluate the antioxidant status like serum catalase (CAT), superoxide dismutase (SOD) and monoamine oxidase (MAO). In human medicine pregnancy is known to be associated with oxidative stress. Oxidative stress produces harmful effects to the developing foetus. Several metabolic changes occur in the maternal body to meet the demand of energy of developing foetus. Due to these changes susceptibility of maternal body increases to oxidative stress. There is paucity of research work on this aspect in nondescript goats. Therefore, the present study was intended to appraise the oxidative stress in pregnant and non-pregnant non-descript goat. Blood samples were collected for serum separation in otherwise healthy pregnant and non-pregnant nondescript goats. Mean values of serum CAT, SOD and MAO were found on a higher side (p≤0.05) with serum SOD values showing a rise of 2.5 times higher than the control healthy value. Correlations among all the three parameters were found to be highly significant (p≤0.01) especially greatest in youngest group of pregnant animals. Illustration of result enlightened the veracity of bumped up production of free radicals in pregnant animals. Technical savoir-faire of oxidative stress supervision is essential for upholding of health status of foetus. The upshot of present study undoubtedly implied the development of oxidative stress in pregnant goats on the basis of altered antioxidant status. These findings conclude that initially the oxidative stress due to pregnancy is critically combated by the intricate defensive mechanism of natural antioxidant system of the body. It appears that this imbalance between oxidant and antioxidant must be checked in time to prevent cellular damage by regularly appraising the antioxidant status through laboratory methods.Keywords: antioxidant, oxidative stress, pregnancy, serum catalase
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