Search results for: lithium oxygen battery

Authors: Reda A. Elkhyat, Mahmoud Nasr, Amel A. Tammam, Mohamed A. Ghazy

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Pharmaceuticals and personal care products (PPCPs) are a unique group of emerging contaminants continuously introduced into the aquatic ecosystem at concentrations capable of inducing adverse effects on humans and aquatic organisms, even at trace levels ranging from ppt to ppm. Amongst the common pharmaceutical emerging pollutants detected in several aquatic environments, acetaminophen has been recognized for its high toxicity. Once released into the aquatic environment, acetaminophen could be degraded by the microbial community and adsorption/ uptake by the plants. Although many studies have investigated the hazard risks of acetaminophen pollutants on aquatic animals, the number of studies demonstrating its removal efficiency and effects on the aquatic plant still needs to be expanded. In this context, this study aims to apply the aquatic plant-based phytoremediation system to eliminate this emerging contaminant from domestic wastewater. The phytoremediation experiment was performed in a hydroponic system containing Eichhornia crassipes and operated under the natural environment at 25°C to 30°C. This system was subjected to synthetic domestic wastewater with the maximum initial chemical oxygen demand (COD) of 390 mg/L and three different acetaminophen concentrations of 25, 50, and 200 mg/L. After 17 d of operation, the phytoremediation system achieved removal efficiencies of about 100% and 85.6±4.2% for acetaminophen and COD, respectively.Moreover, the Eichhornia crassipes could withstand the toxicity associated with increasing the acetaminophen concentrations from 25 to 200 mg/L. This high treatment performance could be assigned to the well-adaptation of the water hyacinth to the phytoremediation factors. Moreover, it has been proposed that this phytoremediation system could be largely supported by phytodegradation and plant uptaking mechanisms; however, detecting the generated intermediates, metabolites, and degradation products are still under investigation. Applying this free-floating plant in wastewater treatment and reducing emerging contaminants would meet the targets of SDGs 3, 6, and. 14. The cost-benefit analysis was performed for the phytoremediation system. The phytoremediation system is financially viable as the net profit was 2921 US $/ y with a payback period of nine years.

Keywords: domestic wastewater, emerging pollutants, hydrophyte Eichhornia crassipes, paracetamol removal efficiency, sustainable development goals (SDGs)

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Authors: Cesar Augusto Hoil Rosas, José Luis Vázquez Burgos, José Juan Carbajal Hernandez

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White fish (Chirostoma estor estor) is an endemic species that habits in the Patzcuaro Lake, located in Michoacan, Mexico; being an important source of gastronomic and cultural wealth of the area. Actually, it have undergone an immense depopulation of individuals, due to the high fishing, contamination and eutrophication of the lake water, resulting in the possible extinction of this important species. This work proposes a new computational model for monitoring and assessment of critical environmental parameters of the white fish ecosystem. According to an Analytical Hierarchy Process, a mathematical model is built assigning weights to each environmental parameter depending on their water quality importance on the ecosystem. Then, a development of an advanced system for the monitoring, analysis and control of water quality is built using the virtual environment of LabVIEW. As results, we have obtained a global score that indicates the condition level of the water quality in the Chirostoma estor ecosystem (excellent, good, regular and poor), allowing to provide an effective decision making about the environmental parameters that affect the proper culture of the white fish such as temperature, pH and dissolved oxygen. In situ evaluations show regular conditions for a success reproduction and growth rates of this species where the water quality tends to have regular levels. This system emerges as a suitable tool for the water management, where future laws for white fish fishery regulations will result in the reduction of the mortality rate in the early stages of development of the species, which represent the most critical phase. This can guarantees better population sizes than those currently obtained in the aquiculture crop. The main benefit will be seen as a contribution to maintain the cultural and gastronomic wealth of the area and for its inhabitants, since white fish is an important food and economical income of the region, but the species is endangered.

Keywords: Chirostoma estor estor, computational system, lab view, white fish

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Authors: Wenjun Zhang, Thao Thi Le, Dongyup Shin, Jong Min Kim

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Electrochemical hydrogen peroxide (H₂O₂) synthesis holds significant promise for decentralized environmental remediation through the electro-Fenton process. However, challenges persist, such as the absence of robust electrocatalysts for the selective two-electron oxygen reduction reaction (2e⁻ ORR) and the high cost and sluggish kinetics of conventional electro-Fenton systems in treating highly concentrated wastewater. This study introduces an efficient water treatment system for removing substantial quantities of organic pollutants using an advanced electro-Fenton system coupled with a high-valent NiO catalyst. By employing a precipitation method involving crystal facet and cation vacancy engineering, a trivalent Ni (Ni³⁺)-rich NiO catalyst with a (111)-domain-exposed crystal facet, named {111}-NivO, was synthesized. This catalyst exhibited a remarkable 96% selectivity and a high mass activity of 59 A g⁻¹ for H₂O₂ production, outperforming all previously reported Ni-based catalysts. Furthermore, an advanced electro-Fenton system, integrated with a flow cell for electrochemical H₂O₂ production, was utilized to achieve 100% removal of 50 ppm bisphenol A (BPA) in 200 mL of wastewater under heavy-duty conditions, reaching a superior rapid degradation rate (4 min, k = 1.125 min⁻¹), approximately 102 times faster than the conventional electro-Fenton system. The hyper-efficiency is attributed to the continuous and appropriate supply of H₂O₂, the provision of O₂, and the timely recycling of the electrolyte under high current density operation. This catalyst also demonstrated a 93% removal of total organic carbon after 2 hours of operation and can be applied for efficient removal of highly concentrated phenol pollutants from aqueous systems, which opens new avenues for wastewater treatment.

Keywords: hydrogen peroxide production, nickel oxides, crystal facet and cation vacancy engineering, wastewater treatment, flow cell, electro-Fenton

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Authors: Tatjana Stefanovic Stanojevic, Milica Tosic Radev, Aleksandra Bogdanovic

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Depression is considered to be a leading cause of death and disability in the female population, and that is the reason why understanding the dynamics of the onset of depressive symptomatology is important. A review of the literature indicates the relationship between depressive symptoms and insecure attachment patterns, but very few studies have examined the mechanism underlying this relation. The aim of the study was to examine the pathway from the preoccupied attachment pattern to depressive symptomatology, as well as to test the mediation effect of mentalization, social anxiety and rumination in this relationship using a serial mediation model. The research was carried out on a geographical cluster sample from the general population of Serbia included within the project ‘Indicators and models of family and work roles harmonization’ funded by the Ministry of Education, Science and Technological Development of the Republic of Serbia. This research was carried out on a subsample of 791 working-age female adults from 37 urban and rural locations distributed through 20 administrative districts of Serbia. The respondents filled in a battery of instruments, including Relationship Questionnaire - Clinical Version (RQ - CV), The Mentalization Scale (MentS), Scale of Social Anxiety (SA), Patient Ruminative Thought Style Questionnaire (RTSQ), Health Questionnaire (PHQ-9). The results confirm our assumption that the total indirect effect of the preoccupied attachment pattern to depressive symptoms is significant across all mediators separately. More importantly, this effect is still present in a model with a sequential mediator relationship, where social anxiety, rumination, and mentalization were perceived as serial mediators of a relationship between preoccupied attachment and depressive symptoms (estimated indirect effect=0.004, boot-strapped 95% CI=0.002 to 0.007). Our findings suggest that there is a significant specific indirect effect of the preoccupied attachment pattern to depressive symptoms, occurring through mentalization, social anxiety and rumination, indicating that preoccupied attachment cause decrease of a self related mentalization, which in turn causes increasing of social anxiety and rumination, concluding in depressive symptoms as a final consequence. The finding that the path from the preoccupied attachment pattern to depressive symptoms is typical in women is understandable from the perspective of both evolutionary and culturally conditioned gender differences. The practical implications of the study are reflected in the recommendations for the prevention and forehand psychotherapy response among preoccupied women with depressive symptomatology. Treatment of this specific group of depressed patients should be focused on strengthening mentalization, learning to accept and to understand herself better, reducing anxiety in situations where mistakes are visible to others, and replacing the rumination strategy with more constructive coping strategies.

Keywords: preoccupied attachment, depression, serial mediation model, mentalization, rumination

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Authors: Naridchaya Aberdour, Joanna Kao, Anne Miller, Timothy Shore, Richard Maher, Zhixin Liu

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Background: COVID-19 has and continues to be a strain on healthcare globally, with the number of patients requiring hospitalization exceeding the level of medical support available in many countries. As chest x-rays are the primary respiratory radiological investigation, the Radiological Assessment of Lung Edema (RALE) score was used to quantify the extent of pulmonary infection on baseline imaging. Assessment of RALE score's reproducibility and associations with clinical outcome parameters were then evaluated to determine implications for patient management and prognosis. Methods: A retrospective study was performed with the inclusion of patients testing positive for COVID-19 on nasopharyngeal swab within a single Local Health District in Sydney, Australia and baseline x-ray imaging acquired between January to June 2020. Two independent Radiologists viewed the studies and calculated the RALE scores. Clinical outcome parameters were collected and statistical analysis was performed to assess RALE score reproducibility and possible associations with clinical outcomes. Results: A total of 78 patients met inclusion criteria with the age range of 4 to 91 years old. RALE score concordance between the two independent Radiologists was excellent (interclass correlation coefficient = 0.93, 95% CI = 0.88-0.95, p<0.005). Binomial logistics regression identified a positive correlation with hospital admission (1.87 OR, 95% CI= 1.3-2.6, p<0.005), oxygen requirement (1.48 OR, 95% CI= 1.2-1.8, p<0.005) and invasive ventilation (1.2 OR, 95% CI= 1.0-1.3, p<0.005) for each 1-point increase in RALE score. For each one year increased in age, there was a negative correlation with recovery (0.05 OR, 95% CI= 0.92-1.0, p<0.01). RALE scores above three were positively associated with hospitalization (Youden Index 0.61, sensitivity 0.73, specificity 0.89) and above six were positively associated with ICU admission (Youden Index 0.67, sensitivity 0.91, specificity 0.78). Conclusion: The RALE score can be used as a surrogate to quantify the extent of COVID-19 infection and has an excellent inter-observer agreement. The RALE score could be used to prognosticate and identify patients at high risk of deterioration. Threshold values may also be applied to predict the likelihood of hospital and ICU admission.

Keywords: chest radiography, coronavirus, COVID-19, RALE score

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Authors: Noor F. Ilias, Mazlifah Omar, Hashbullah Ismail

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Exercise training has been shown to improve functional capacity and is recommended as a therapy for management of blood pressure. Our purpose was to establish whether different exercise capacity produces different effect size for Cardiorespiratory Fitness (CRF), systolic (SBP) and diastolic (DBP) blood pressure in patients with hypertension. Exercise characteristic is required in order to have optimal benefit from the training, but optimal exercise capacity is still unwarranted. A MEDLINE search (1985 to 2015) was conducted for exercise based rehabilitation trials in hypertensive patients. Thirty-seven studies met the selection criteria. Of these, 31 (83.7%) were aerobic exercise and 6 (16.3%) aerobic with additional resistance exercise, providing a total of 1318 exercise subjects and 819 control, the total of subjects was 2137. We calculated exercise volume and energy expenditure through the description of exercise characteristics. 4 studies (18.2%) were 451kcal - 900 kcal, 12 (54.5%) were 900 kcal – 1350 kcal and 6 (27.3%) >1351kcal per week. Peak oxygen consumption (peak VO2) increased by mean difference of 1.44 ml/kg/min (95% confidence interval [CI]: 1.08 to 1.79 ml/kg/min; p = 0.00001) with weighted mean 21.2% for aerobic exercise compare to aerobic with additional resistance exercise 4.50 ml/kg/min (95% confidence interval [CI]: 3.57 to 5.42 ml/kg/min; p = 0.00001) with weighted mean 14.5%. SBP was clinically reduce for both aerobic and aerobic with resistance training by mean difference of -4.66 mmHg (95% confidence interval [CI]: -5.68 to -3.63 mmHg; p = 0.00001) weighted mean 6% reduction and -5.06 mmHg (95% confidence interval [CI]: -7.32 to -2.8 mmHg; p = 0.0001) weighted mean 5% reduction respectively. Result for DBP was clinically reduce for aerobic by mean difference of -1.62 mmHg (95% confidence interval [CI]: -2.09 to -1.15 mmHg; p = 0.00001) weighted mean 4% reduction and aerobic with resistance training reduce by mean difference of -3.26 mmHg (95% confidence interval [CI]: -4.87 to -1.65 mmHg; p = 0.0001) weighted mean 6% reduction. Optimum exercise capacity for 451 kcal – 900 kcal showed greater improvement in peak VO2 and SBP by 2.76 ml/kg/min (95% confidence interval [CI]: 1.47 to 4.05 ml/kg/min; p = 0.0001) with weighted mean 40.6% and -16.66 mmHg (95% confidence interval [CI]: -21.72 to -11.60 mmHg; p = 0.00001) weighted mean 9.8% respectively. Our data demonstrated that aerobic exercise with total volume of 451 kcal – 900 kcal/ week energy expenditure may elicit greater changes in cardiorespiratory fitness and blood pressure in hypertensive patients. Higher exercise capacity weekly does not seem better result in management hypertensive patients.

Keywords: blood Pressure, exercise, hypertension, peak VO2

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Authors: Tooba Aslam, Efthalia Chatzisymeon

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UV-assisted irradiation technologies are well-established for water and wastewater treatment. UVC treatments are widely used at large-scale, while UVA irradiation has more often been applied in combination with a catalyst (e.g. TiO₂ or FeSO₄) in smaller-scale systems. A technical issue of these systems is the formation of fouling on the quartz sleeves that houses the lamps. This fouling can prevent complete irradiation, therefore reducing the efficiency of the process. This paper investigates the effects of operational parameters, such as the type of wastewater, irradiation source, H₂O₂ addition, and water pH on fouling formation and, ultimately, the treatment of municipal wastewater. Batch experiments have been performed at lab-scale while monitoring water quality parameters including: COD, TS, TSS, TDS, temperature, pH, hardness, alkalinity, turbidity, TOC, UV transmission, UV₂₅₄ absorbance, and metal concentrations. The residence time of the wastewater in the reactor was 5 days in order to observe any fouling formation on the quartz surface. Over this period, it was observed that chemical oxygen demand (COD) decreased by 30% and 59% during photolysis (Ultraviolet A) and photo-catalysis (UVA/Fe/H₂O₂), respectively. Higher fouling formation was observed with iron-rich and phosphorous-rich wastewater. The highest rate of fouling was developed with phosphorous-rich wastewater, followed by the iron-rich wastewater. Photo-catalysis (UVA/Fe/H₂O₂) had better removal efficiency than photolysis (UVA). This was attributed to the Photo-Fenton reaction, which was initiated under these operational conditions. Scanning electron microscope (SEM) measurements of fouling formed on the quartz sleeves showed that particles vary in size, shape, and structure; some have more distinct structures and are generally larger and have less compact structure than the others. Energy-dispersive X-ray spectroscopy (EDX) results showed that the major metals present in the fouling cake were iron, phosphorous, and calcium. In conclusion, iron-rich wastewaters are more suitable for UV-assisted treatment since fouling formation on quartz sleeves can be minimized by the formation of oxidizing agents during treatment, such as hydroxyl radicals.

Keywords: advanced oxidation processes, photo-fenton treatment, photo-catalysis, wastewater treatment

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Authors: Mohammed S. Bhader, Abdullah A. Ghaddaf, Anas Alamoudi, Amal Abualola, Renad Kalantan, Noura Alkhulaifi, Ibrahim Halawani, Mohammed Alhindi

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Background: Noninvasive neurally adjusted ventilatory assist (NAVA) is a relatively new mode of noninvasive ventilation with promising clinical and patient-ventilator outcomes for preterm infants. The aim of this systematic review was to compare NAVA to nasal continuous or positive airway pressure (NCPAP) or intermittent positive airway pressure (NIPP) for preterm infants. Methods: We searched the online databases Medline, Embase, and CENTRAL. We included randomized controlled trials (RCTs) that compared NAVA to NCPAP or NIPP for preterm infants < 37 weeks gestational age. We sought to evaluate the following outcomes: noninvasive intubation failure rate, desaturation rate, the fraction of inspired oxygen (FiO2), and length of stay in the neonatal intensive care unit (NICU). We used the mean difference (MD) to represent continuous outcomes, while the odds ratio (OR) was used to represent dichotomous outcomes. Results: A total of 11 RCTs that enrolled 429 preterm infants were deemed eligible. NAVA showed similar clinical outcomes to NCPAP or NIPP with respect to noninvasive intubation failure (RR for NAVA versus NCPAP: 0.82, 95% confidence interval (CI): 0.49 to 1.37), desaturation rate (RR for NAVA versus NCPAP: 0.69, 95%CI: 0.36 to 1.29; RR for NAVA versus NIPP: 0.58, 95%CI: 0.08 to 4.25), FiO2 (MD for NAVA versus NCPAP: –0.01, 95%CI: –0.04 to 0.02; MD for NAVA versus NIPP: –7.16, 95%CI: –22.63 to 8.31), and length of stay in the NICU (MD for NAVA versus NCPAP: 1.34, 95%CI: –4.17 to 6.85). Conclusion: NAVA showed similar clinical and ventilator-related outcomes compared to the usual care noninvasive respiratory support measures NCPAP or NIPP for preterm infants.

Keywords: preterm infants, noninvasive neurally adjusted ventilatory assist, NIV-NAVA, non-invasive ventilation, nasal continuous or positive airway pressure, NCPAP, intermittent positive airway pressure ventilation, NIPP, respiratory distress syndrome, RDS

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Authors: Deborah Bailey-Rodriguez, Maria Paula Valdivieso Rueda, Gemma Reynolds

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In recent years, the mental health of Higher Education (HE) students has been a growing concern. This has been further exacerbated by the stresses associated with the Covid-19 pandemic, placing students at even greater risk of developing mental health issues. Support available to students in HE tends to follow an established and traditional route. The demands for counseling services have grown, not only with the increase in student numbers but with the number of students seeking support for mental health issues, with 94% of HE institutions recently reporting an increase in the need for counseling services. One way of improving the well-being and mental health of HE students is through the use of brief interventions, such as expressive writing (EW). This intervention involves encouraging individuals to write continuously for at least 15-20 minutes for three to five sessions (often on consecutive days) about their deepest thoughts and feelings to explore significant personal experiences in a meaningful way. Given the brevity, simplicity and cost-effectiveness of EW, this intervention has considerable potential as an intervention for HE populations. The current study, therefore, employed a mixed-methods design to explore the effectiveness of EW in reducing anxiety, general stress, academic stress and depression in HE students while improving well-being. HE students at MDX were randomly assigned to one of three conditions: (1) The UniExp-EW group was required to write about their emotions and thoughts about any stressors they have faced that are directly relevant to their university experience (2) The NonUniExp-EW group was required to write about their emotions and thoughts about any stressors that are NOT directly relevant to their university experience, and (3) The Control group were required to write about how they spent their weekend, with no reference to thoughts or emotions, and without thinking about university. Participants were required to carry out the EW intervention for 15 minutes per day for four consecutive days. Baseline mental health and well-being measures were taken before the intervention via a battery of standardized questionnaires. Following completion of the intervention on day four, participants were required to complete the questionnaires a second time and again one week later. Participants were also invited to attend focus groups to discuss their experience of the intervention. This will allow an in-depth investigation into students’ perceptions of EW as an effective intervention to determine whether they would choose to use this intervention in the future. Preliminary findings will be discussed at the conference as well as a discussion of the important implications of the findings. The study is fundamental because if EW is an effective intervention for improving mental health and well-being in HE students, its brevity and simplicity mean it can be easily implemented and can be freely available to students. Improving the mental health and well-being of HE students can have knock-on implications for improving academic skills and career development.

Keywords: expressive writing, higher education, psychology in education, mixed-methods, mental health, academic stress

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Authors: Indika Fernando, Jiangang Fei, Roger Stanely, Hossein Enshaei

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Ever increasing demand for quality fresh produce by the consumers, had increased the gravity on the post-harvest supply chains in multi-fold in the recent years. Mechanical injury to fresh produce was a critical factor for produce wastage, especially with the expansion of supply chains, physically extending to thousands of miles. The impact of vibration damages in transit was identified as a specific area of focus which results in wastage of significant portion of the fresh produce, at times ranging from 10% to 40% in some countries. Several studies were concentrated on quantifying the impact of vibration to fresh produce, and it was a challenge to collect vibration impact data continuously due to the limitations in battery life or the memory capacity in the devices. Therefore, the study samples were limited to a stretch of the transit passage or a limited time of the journey. This may or may not give an accurate understanding of the vibration impacts encountered throughout the transit passage, which limits the accuracy of the results. Consequently, an approach which can extend the capacity and ability of determining vibration signals in the transit passage would contribute to accurately analyze the vibration damage along the post-harvest supply chain. A mechanism was developed to address this challenge, which is capable of measuring the in transit vibration continuously through the transit passage subject to a minimum acceleration threshold (0.1g). A system, consisting six tri-axel vibration transducers installed in different locations inside the cargo (produce) pallets in the truck, transmits vibration signals through LORA (Long Range Radio) technology to a central device installed inside the container. The central device processes and records the vibration signals transmitted by the portable transducers, along with the GPS location. This method enables to utilize power consumption for the portable transducers to maximize the capability of measuring the vibration impacts in the transit passage extending to days in the distribution process. The trial tests conducted using the approach reveals that it is a reliable method to measure and quantify the in transit vibrations along the supply chain. The GPS capability enables to identify the locations in the supply chain where the significant vibration impacts were encountered. This method contributes to determining the causes, susceptibility and intensity of vibration impact damages to fresh produce in the post-harvest supply chain. Extensively, the approach could be used to determine the vibration impacts not limiting to fresh produce, but for products in supply chains, which may extend from few hours to several days in transit.

Keywords: post-harvest, supply chain, wireless transducers, LORA, fresh produce

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Authors: Hager E. Amer, Hany El Saftawy, Laila Rashed, Ahmed M. Ata, Fatma Metwally, Hesham Mettawei, Hossam E. Sayed, Tamer Adel, Kareem M. El Sawah

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Aim: The purpose of this study is to regenerate the damaged photoreceptor cells as a result of argon laser as a model of Retinitis Pigmentosa in rabbits' retina by using adult stem cells from rabbits' bone marrow. Background: Retinitis pigmentosa (RP) is a group of inherited disorders that primarily affect photoreceptor and pigment epithelium function. RP leads to loss of the rod outer segment and shorten the photoreceptor layer and expose the photoreceptor cell body to high-pressure levels in oxygen (oxidative stress) leads to apoptosis to the rod and cone cells. In particular, there is no specific treatment for retinitis pigmentosa. Materials and Methods: Forty Two Giant (Rex) rabbits were used in this experiment divided into 3 groups: Group 1: Control (6 rabbits), Group 2: Argon laser radiated as a model of retinitis pigmentosa (12 rabbits), Group 3: Laser radiated and treated by 6 million stem cells (12 rabbits). The last two groups are divided each into two subgroups each subgroup contains 6 rabbits, the ophthalmological examination was performed on rabbits, blood samples and retina samples were taken after 25 days and after 36 days from the laser radiation (10 days and 21 days after stem cells insertion in group 3) to perform the biochemical analysis. Results: Compared to control Group, a decrease of ERG wave amplitude and antioxidant substances (Glutathione) in blood and retina in group 2, and an increase of oxidative stress substances (Nitric oxide, Malonaldehyde, and carponyl protein) and apoptotic substances (Advanced glycation end product and M-metalloproteinase) in blood and retina. Compared to group 2, mostly increases of antioxidant substances and ERG wave amplitude in group 3, and mostly decreases in oxidative stress substances and apoptotic substances. Conclusion: Insertion of 6 million stem cells intravitreous gives good results in regeneration of the damaged photoreceptor cells after 21 days.

Keywords: retinitis pigmentosa, stem cells, argon laser, oxidative stress, apoptosis

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Authors: Isomar Lima da Silva, Alcilene Batalha Pontes, Aristeu Jonatas Leite de Oliveira, Roberto Maia Augusto

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Context: Mechanical ventilators are medical devices that help provide oxygen and ventilation to patients with respiratory difficulties. This equipment consists of a manual breathing unit that can be operated by a doctor or nurse and a mechanical ventilator that controls the airflow and pressure in the patient's respiratory system. This type of ventilator is commonly used in emergencies and intensive care units where it is necessary to provide breathing support to critically ill or injured patients. Objective: In this context, this work aims to develop a reliable and low-cost mechanical ventilator to meet the demand of hospitals in treating people affected by Covid-19 and other severe respiratory diseases, offering a chance of treatment as an alternative to mechanical ventilators currently available in the market. Method: The project presents the development of a low-cost auxiliary ventilator with a controlled ventilatory system assisted by integrated hardware and firmware for respiratory cycle control in non-invasive mechanical ventilation treatments using a manual artificial respiration unit. The hardware includes pressure sensors capable of identifying positive expiratory pressure, peak inspiratory flow, and injected air volume. The embedded system controls the data sent by the sensors. It ensures efficient patient breathing through the operation of the sensors, microcontroller, and actuator, providing patient data information to the healthcare professional (system operator) through the graphical interface and enabling clinical parameter adjustments as needed. Results: The test data of the developed mechanical ventilator presented satisfactory results in terms of performance and reliability, showing that the equipment developed can be a viable alternative to commercial mechanical ventilators currently available, offering a low-cost solution to meet the increasing demand for respiratory support equipment.

Keywords: mechanical fans, breathing, medical equipment, COVID-19, intensive care units

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Authors: Adkham Paiziev, Fikrat Kerimov

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Near Infrared Spectroscopy (NIRS) is one of the biophotonic techniques which can be used to monitor oxygenation and hemodynamics in a variety of human tissues, including skeletal muscle. In the present work, we are offering tissue oximetry (OxyPrem) to measure hemodynamic parameters of skeletal muscles in rest and exercise. Purpose: - To elaborate the new wireless, portable, noninvasive, wearable NIRS device to measure skeletal muscle oxygenation during exercise. - To test this device on brachioradialis muscle of wrestler volunteers by using combined method of arterial occlusion (AO) and NIRS (AO+NIRS). Methods: Oxyprem NIRS device has been used together with AO test. AO test and Isometric brachioradialis muscle contraction experiments have been performed on one group of wrestler volunteers. ‘Accu- Measure’ caliper (USA) to measure skinfold thickness (SFT) has been used. Results: Elaborated device consists on power supply box, a sensor head and installed ‘Tubis’ software for data acquisition and to compute deoxyhemoglobin ([HHb), oxyhemoglobin ([O2Hb]), tissue oxygenation (StO2) and muscle tissue oxygen consumption (mVO2). Sensor head consists on four light sources with three light emitting diodes with nominal wavelengths of 760 nm, 805 nm, and 870 nm, and two detectors. AO and isometric voluntary forearm muscle contraction (IVFMC) on five healthy male subjects (23,2±0.84 in age, 0.43±0.05cm of SFT ) and four female subjects (22.0±1.0 in age and 0.24±0.04 cm SFT) has been measured. mVO2 for control group has been calculated (-0.65%/sec±0.07) for male and -0.69%/±0.19 for female subjects). Tissue oxygenation index for wrestlers in average about 75% whereas for control group StO2 =63%. Second experiment was connected with quality monitoring muscle activity during IVFMC at 10%,30% and 50% of MVC. It has been shown, that the concentration changes of HbO2 and HHb positively correlated to the contraction intensity. Conclusion: We have presented a portable multi-channel wireless NIRS device for real-time monitoring of muscle activity. The miniaturized NIRS sensor and the usage of wireless communication make the whole device have a compact-size, thus can be used in muscle monitoring.

Keywords: skeletal muscle, oxygenation, instrumentation, near infrared spectroscopy

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Authors: Arunas Emeljanovas, Brigita Mieziene, Vida Cesnaitiene, Ingunn Fjortoft, Lise Kjonniksen

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Background: Gender differences in physical fitness were tracked in many studies with lower effect in preschool children and increasing difference among genders across age. In Lithuania, on a population level, secular trends in physical fitness were regularly observed each ten years for the last two decades for 11-18 years old students. However, there is apparently a lack of such epidemiological studies among primary school students. Assessing and monitoring physical fitness from an early age is of particular importance seeking to develop and strengthen physical abilities of youths for future health benefits. The goal of the current study was to indicate age and gender differences in anthropometric measures, musculoskeletal, motor and cardiorespiratory fitness in Lithuanian primary school children. Methods: The study included 3456 1-4th grade students from 6 to 10 years. The data reliably represents the population of primary school children in Lithuania. Among them, 1721 (49.8 percent) were boys. Physical fitness was measured by the 9-item test battery, developed by Fjørtoft and colleagues (2011). Height and weight were measured and body mass index was calculated. Student t test evaluated differences in physical fitness between boys and girls, ANOVA was performed to indicate differences across age. Results: All anthropometric and fitness means that were identified as significantly different were better in boys than in girls and in older than younger students (p < .05). Among anthropometric measures, height was higher in boys aged 7 through 9 years. Weight and BMI differed among boys and girls only at 8 years old. Means of height and weight increased significantly across all ages. Among musculoskeletal fitness tests, means of standing broad jump, throwing a tennis ball and pushing a medicine ball were different between genders within each age group and across all ages. Differences between genders were less likely in motor fitness than in musculoskeletal or cardiorespiratory fitness. Differences in means of shuttle run 10 x 5 test between genders occurred at age 6, 9 and 10 years; running 20 m at age 6 and 9 years, and climbing wall bars at age 9 and 10. Means of Reduced Cooper test representing cardiorespiratory fitness were different between genders within each age group but did not differ among age 6 and 8 as well as 7 and 8 years in boys, and among age 7 and 8 years in girls. Conclusion: In general, the current study confirms gender differences in musculoskeletal, motor and cardiorespiratory fitness found in other studies across the world in primary school and older children. Observed gender differences might be explained by higher physical activity in boys rather than girls. As it is explained by previous literature, older boys and girls had better performances than younger ones, because of the components of fitness change as a function of growth, maturation, development, and interactions among the three processes.

Keywords: primary school children, motor fitness, musculoskeletal fitness, cardiovascular fitness

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Authors: Saima Saleem, Zubair Abbasi, Abdul Hameed, Mansoor Ahmed Khan, Navid Rashid Qureshi, Abid Azhar

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Oral Squamous Cell Carcinoma (OSCC) is the leading cause of death in the developing countries like Pakistan. This problem aggravates because of the excessive use of available chewing products. In spite of widespread information on their use and purported legislations against their use the Pakistani markets are classical examples of selling chewable carcinogenic mutagens. Reported studies indicated that these products are rich in reactive oxygen species (ROS) and polyphenols. TP53 gene is involved in the suppression of tumor. It has been reported that somatic mutations caused by TP53 gene are the foundation of the cancer. This study aims to find the loss of TP53 functions due to mutation/polymorphism caused by genomic alteration and interaction with tobacco and its related ingredients. Total 260 tissues and blood specimens were collected from OSCC patients and compared with age and sex matched controls. Mutations in exons 2-11 of TP53 were examined by PCR-SSCP. Samples showing mobility shift were directly sequenced. Two mutations were found in exon 4 at nucleotide position 108 and 215 and one in exon 7 at nucleotide position 719 of the coding sequences in patient’s tumor samples. These results show that substitution of proline with arginine at codon 72 and serine with threonine at codon 240 of p53 protein. These polymorphic changes, found in tumor samples of OSCC, could be involved in loss of heterozygocity and apoptotic activity in the binding domain of TP53. The model of the mutated TP53 gene elaborated a nonfunctional unfolded p53 protein, suggesting an important role of these mutations in p53 protein inactivation and malfunction. This nonfunctional 3D model also indicates that exogenous tobacco related carcinogens may act as DNA-damaging agents affecting the structure of DNA. The interpretations could be helpful in establishing the pathways responsible for tumor formation in OSCC patients.

Keywords: TP53 mutation/polymorphism, OSCC, PCR-SSCP, direct DNA sequencing, 3D structure

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Authors: Malab Sana Balouch, Meenakshi Nayar

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Hemispatial Neglect is a common disorder primarily associated with right hemispheric stroke, in the acute phase of which it can occur up to 82% of the time. Such individuals fail to acknowledge or respond to people and objects in their left field of vision due to deficits in attention and awareness. Persistent hemispatial neglect significantly impedes post-stroke recovery, leading to longer hospital stays post-stroke, increased functional dependency, longer-term disability in ADLs and increased risk of falls. Recently, evidence has emerged for the use of dopamine agonist Rotigotine in neglect. The aim of our Quality Improvement Project (QIP) is to evaluate and better the current protocols and practice in assessment, documentation and management of neglect and rotigotine use at the Neurorehabilitation unit at Charing Cross Hospital (CNRU). In addition, it brings light to rotigotine use in the management of hemispatial neglect and paves the way for future research in the field. Our QIP was based in the CNRU. All patients admitted to the CNRU suffering from a right-sided stroke from 2nd of February 2018 to the 2nd of February 2021 were included in the project. Each patient’s multidisciplinary team report and hospital notes were searched for information, including bio-data, fulfilment of the inclusion criteria (having hemispatial neglect) and data related to rotigotine use. This includes whether or not the drug was administered, any contraindications to drug in patients that did not receive it, and any therapeutic benefits(subjective or objective improvement in neglect) in those that did receive the rotigotine. Data was simultaneously entered into excel sheet and further statistical analysis was done on SPSS 20.0. Out of 80 patients suffering from right sided strokes, 72.5% were infarcts and 27.5% were hemorrhagic strokes, with vast majority of both types of strokes were in the middle cerebral artery territory (MCA). A total of 31 (38.8%) of our patients were noted to have hemispatial neglect, with the highest number of cases being associated with MCA strokes. Almost half of our patients with MCA strokes suffered from neglect. Neglect was more common in male patients. Out of the 31 patients suffering from visuospatial neglect, only 16% actually received rotigotine and 80% of them were noted to have an objective improvement in their neglect tests and 20% revealed subjective improvement. After thoroughly going through neglect-associated documentation, the following recommendations/plans were put in place for the future. We plan to liaise with the occupational therapy team at our rehab unit to set a battery of tests that would be done on all patients presenting with neglect and recommend clear documentation of outcomes of each neglect screen under it. Also to create two proformas; one for the therapy team to aid in systematic documentation of neglect screens done prior to and after rotigotine administration and a second proforma for the medical team with clear documentation of rotigotine use, its benefits and any contraindications if not administered.

Keywords: hemispatial Neglect, right hemispheric stroke, rotigotine, neglect, dopamine agonist

Procedia PDF Downloads 55

Authors: N. B. Ikenweiwe, A. A. Alimi, N. A. Bamidele, A. O. Ewumi, J. Dairo, I. A. Akinnubi, S. O. Otubusin

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A study on the physical, chemical and biological parameters of the lower course of Ogun River, Isheri-Olofin was carried out between January and December 2014 in order to determine the effects of the anthropogenic activities of the Kara abattoir and domestic waste depositions on the quality of the water. Water samples were taken twice each month at three selected stations A, B and C (based on characteristic features or activity levels) along the water course. Samples were analysed using standard methods for chemical and biological parameters the same day in the laboratory while physical parameters were determined in-situ with water parameters kit. Generally, results of Transparency, Dissolved Oxygen, Nitrates, TDS and Alkalinity fall below the permissible limits of WHO and FEPA standards for drinking and fish production. Results of phosphates, lead and cadmium were also low but still within the permissible limit. Only Temperature and pH were within limit. Low plankton community, (phytoplankton, zooplankton), which ranges from 3, 5 to 40, 23 were as a result of low levels of DO, transparency and phosphate. The presence of coliform bacteria of public health importance like Escherichia coli, Proteus vulgaris, Aeromonas sp., Shigella sp, Enterobacter aerogenes as well as gram negative bacteria Proteus morganii are mainly indicators of faecal pollution. Fish and other resources obtained from this water stand the risk of being contaminated with these organisms and man is at the receiving end. The results of the physical, chemical and some biological parameters of Isheri, Ogun River, according to this study showed that the live forms of aquatic and fisheries resources there are dwelling under stress as a result of deposition of bones, horns, faecal components, slurry of suspended solids, fat and blood into the water. Government should therefore establish good monitoring system against illegal waste depositions and create education programmes that will enlighten the community on the social, ecological and economic values of the river.

Keywords: water parameters, Isheri Ogun river, anthropogenic activities, Kara abattoir

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Authors: Usman Bawa

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Macro-invertebrates have been used to monitor organic pollution in rivers and streams. Several biotic indices based on macro-invertebrates have been developed over the years including the Biological Monitoring Working Party (BMWP). A new biotic index, the Gammarus:Asellus ratio has been recently proposed as an index of organic pollution. This study tested the validity of the Gammarus:Asellus ratio as an index of organic pollution, by examining the relationship between the Gammarus:Asellus ratio and physical-chemical parameters, and other biotic indices such as BMWP and, Average Score Per Taxon (ASPT) from lakes and streams at Markeaton Park, Allestree Park, and Kedleston Hall, Derbyshire. Macro invertebrates were sampled using the standard five-minute kick sampling techniques physical and chemical environmental variables were obtained based on standard sampling techniques. Eighteen sites were sampled, six sites from Markeaton Park (three sites across the stream and three sites across the lake). Six sites each were also sampled from Allestree Park and Kedleston Hall lakes. The Gammarus:Asellus ratio showed an opposite significant positive correlations with parameters indicative of organic pollution such as the level of nitrates, phosphates, and calcium and also revealed a negatively significant correlations with other biotic indices (BMWP/ASPT). The BMWP score correlated positively significantly with some water quality parameters such as dissolved oxygen and flow rate, but revealed no correlations with other chemical environmental variables. The BMWP score was significantly higher in the stream than the lake in Markeaton Park, also The ASPT scores appear to be significantly higher in the upper Lakes than the middle and lower lakes. This study has further strengthened the use of BMWP/ASPT score as an index of organic pollution. But, additional application is required to validate the use of Gammarus:Asellus as a rapid bio monitoring tool.

Keywords: Asellus, biotic index, Gammarus, macro invertebrates, organic pollution

Procedia PDF Downloads 319

Authors: Tânia F. C. V. Silva, Eloísa S. S. Vieira, João Pinto da Costa, Rui A. R. Boaventura, Vitor J. P. Vilar

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Sanitary landfill leachates are characterized as a complex mixture of diverse organic and inorganic contaminants, which are usually removed by combining different treatment processes. Due to its simplicity, reliability, high cost-effectiveness and high nitrogen content (mostly under the ammonium form) inherent in this type of effluent, the activated sludge biological process is almost always applied in leachate treatment plants (LTPs). The purpose of this work is to assess the effect of the main nitrification and denitrification variables on the nitrogen's biological removal, from mature leachates. The leachate samples were collected after an aerated lagoon, at a LTP nearby Porto, presenting a high amount of dissolved organic carbon (1.0-1.3 g DOC/L) and ammonium nitrogen (1.1-1.7 g NH4+-N/L). The experiments were carried out in a 1-L lab-scale batch reactor, equipped with a pH, temperature and dissolved oxygen (DO) control system, in order to determine the reaction kinetic constants at unchanging conditions. The nitrification reaction rate was evaluated while varying the (i) operating temperature (15, 20, 25 and 30ºC), (ii) DO concentration interval (0.5-1.0, 1.0-2.0 and 2.0-4.0 mg/L) and (iii) solution pH (not controlled, 7.5-8.5 and 6.5-7.5). At the beginning of most assays, it was verified that the ammonium stripping occurred simultaneously to the nitrification, reaching up to 37% removal of total dissolved nitrogen. The denitrification kinetic constants and the methanol consumptions were calculated for different values of (i) volatile suspended solids (VSS) content (25, 50 and 100 mL of centrifuged sludge in 1 L solution), (ii) pH interval (6.5-7.0, 7.5-8.0 and 8.5-9.0) and (iii) temperature (15, 20, 25 and 30ºC), using effluent previously nitrified. The maximum nitrification rate obtained was 38±2 mg NH4+-N/h/g VSS (25ºC, 0.5-1.0 mg O2/L, pH not controlled), consuming 4.4±0.3 mg CaCO3/mg NH4+-N. The highest denitrification rate achieved was 19±1 mg (NO2--N+NO3--N)/h/g VSS (30ºC, 50 mL of sludge and pH between 7.5 and 8.0), with a C/N consumption ratio of 1.1±0.1 mg CH3OH/mg (NO2--N+NO3--N) and an overall alkalinity production of 3.7±0.3 mg CaCO3/mg (NO2--N+NO3--N). The denitrification process showed to be sensitive to all studied parameters, while the nitrification reaction did not suffered significant change when DO content was changed.

Keywords: mature sanitary landfill leachate, nitrogen removal, nitrification and denitrification parameters, lab-scale activated sludge biological reactor

Procedia PDF Downloads 252

Authors: María Magdalena Méndez-González, Miguel García Rocha, Carlos Manuel Yermo De la Cruz

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Calcium phosphate (Ca5(PO4)3(X)) is widely used in orthopedic applications and is widely used as powder and granules. However, their presence in bone is in the form of nanometric needles 60 nm in length with a non-stoichiometric phase of apatite contains CO3-2, Na+, OH-, F-, and other ions in a matrix of collagen fibers. The crystal size, morphology control and interaction with cells are essential for the development of nanotechnology. The structural results of calcium phosphate, synthesized by chemical precipitation with crystal size of 22.85 nm are presented in this paper. The calcium phosphate powders were analyzed by X-ray diffraction, energy dispersive spectroscopy (EDS), infrared spectroscopy and FT-IR transmission electron microscopy. Network parameters, atomic positions, the indexing of the planes and the calculation of FWHM (full width at half maximum) were obtained. The crystal size was also calculated using the Scherer equation d (hkl) = cλ/βcosѲ. Where c is a constant related to the shape of the crystal, the wavelength of the radiation used for a copper anode is 1.54060Å, Ѳ is the Bragg diffraction angle, and β is the width average peak height of greater intensity. Diffraction pattern corresponding to the calcium phosphate called hydroxyapatite phase of a hexagonal crystal system was obtained. It belongs to the space group P63m with lattice parameters a = 9.4394 Å and c = 6.8861 Å. The most intense peak is obtained 2Ѳ = 31.55 (FWHM = 0.4798), with a preferred orientation in 121. The intensity difference between the experimental data and the calculated values is attributable to the temperature at which the sintering was performed. The intensity of the highest peak is at angle 2Ѳ = 32.11. The structure of calcium phosphate obtained was a hexagonal configuration. The intensity changes in the peaks of the diffraction pattern, in the lattice parameters at the corners, indicating the possible presence of a dopant. That each calcium atom is surrounded by a tetrahedron of oxygen and hydrogen was observed by infrared spectra. The unit cell pattern corresponds to hydroxyapatite and transmission electron microscopic crystal morphology corresponding to the hexagonal phase with a preferential growth along the c-plane was obtained.

Keywords: structure, nanoparticles, calcium phosphate, metallurgical and materials engineering

Procedia PDF Downloads 484

Authors: Sarra K. Ikhlef, Onita Basu

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Natural organic matter (NOM) removal efficiency using drinking water treatment biological filters can be highly influenced by backwashing conditions. Backwashing has the ability to remove the accumulated biomass and particles in order to regenerate the biological filters' removal capacity and prevent excessive headloss buildup. A lab scale system consisting of 3 biological filters was used in this study to examine the implications of different backwash strategies on biological filtration performance. The backwash procedures were evaluated based on their impacts on dissolved organic carbon (DOC) removals, biological filters’ biomass, backwash water volume usage, and particle removal. Results showed that under nutrient limited conditions, the simultaneous use of air and water under collapse pulsing conditions lead to a DOC removal of 22% which was significantly higher (p>0.05) than the 12% removal observed under water only backwash conditions. Employing a bed expansion of 20% under nutrient supplemented conditions compared to a 30% reference bed expansion while using the same amount of water volume lead to similar DOC removals. On the other hand, utilizing a higher bed expansion (40%) lead to significantly lower DOC removals (23%). Also, a backwash strategy that reduced the backwash water volume usage by about 20% resulted in similar DOC removals observed with the reference backwash. The backwash procedures investigated in this study showed no consistent impact on biological filters' biomass concentrations as measured by the phospholipids and the adenosine tri-phosphate (ATP) methods. Moreover, none of these two analyses showed a direct correlation with DOC removal. On the other hand, dissolved oxygen (DO) uptake showed a direct correlation with DOC removals. The addition of the extended terminal subfluidization wash (ETSW) demonstrated no apparent impact on DOC removals. ETSW also successfully eliminated the filter ripening sequence (FRS). As a result, the additional water usage resulting from implementing ETSW was compensated by water savings after restart. Results from this study provide insight to researchers and water treatment utilities on how to better optimize the backwashing procedure for the goal of optimizing the overall biological filtration process.

Keywords: biological filtration, backwashing, collapse pulsing, ETSW

Procedia PDF Downloads 254

Authors: Min Liu, Jirui Gong, Qinpu Luo, Lili Yang, Bo Yang, Zihe Zhang, Yan Pan, Zhanwei Zhai

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Grazing disturbance is one of the important land-use types that affect plant growth and ecosystem processes. In order to study the responses of dominant species to grazing in the semiarid temperate grassland of Inner Mongolia, we set five grazing intensity plots: a control and four levels of grazing (light (LG), moderate (MG), heavy (HG) and extreme heavy grazing (EHG)) to test the morphological and physiological responses of Stipa grandis, Leymus chinensis at the individual levels. With the increase of grazing intensity, Stipa grandis and Leymus chinensis both exhibited reduced plant height, leaf area, stem length and aboveground biomass, showing a significant dwarf phenomenon especially in HG and EHG plots. The photosynthetic capacity decreased along the grazing gradient. Especially in the MG plot, the two dominant species have lowest net photosynthetic rate (Pn) and water use efficiency (WUE). However, in the HG and EHG plots, the two species had high light saturation point (LSP) and low light compensation point (LCP), indicating they have high light-use efficiency. They showed a stimulation of compensatory photosynthesis to the remnant leaves as compared with grasses in MG plot. For Leymus chinensis, the lipid peroxidation level did not increase with the low malondialdehyde (MDA) content even in the EHG plot. It may be due to the high enzymes activity of superoxide dismutase (SOD) and peroxidase (POD) to reduce the damage of reactive oxygen species. Meanwhile, more carbohydrate was stored in the leaf of Leymus chinensis to provide energy to the plant regrowth. On the contrary, Stipa grandis showed the high level of lipid peroxidation especially in the HG and EHG plots with decreased antioxidant enzymes activity. The soluble protein content did not change significantly in the different plots. Therefore, with the increase of grazing intensity, plants changed morphological and physiological traits to defend themselves effectively to herbivores. Leymus chinensis is more resistant to grazing than Stipa grandis in terms of tolerance traits, particularly under heavy grazing pressure.

Keywords: antioxidant enzymes activity, grazing density, morphological responses, photosynthesis

Procedia PDF Downloads 339

Authors: B. Vinod, L. Jsudev

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Natural fibers as reinforcement in polymer matrix material is gaining lot of attention in recent years, as they are light in weight, less in cost, and ecologically advanced surrogate material to glass and carbon fibers in composites. Natural fibers like jute, sisal, coir, hemp, banana etc. have attracted substantial importance as a potential structural material because of its attractive features along with its good mechanical properties. Cryogenic applications of natural fiber reinforced polymer composites like cryogenic wind tunnels, cryogenic transport vessels, support structures in space shuttles and rockets are gaining importance. In these unique cryogenic applications, the requirements of polymer composites are extremely severe and complicated. These materials need to possess good mechanical and physical properties at cryogenic temperatures such as liquid helium (4.2 K), liquid hydrogen (20 K), liquid nitrogen (77 K), and liquid oxygen (90 K) temperatures, etc., to meet the high requirements by the cryogenic engineering applications. The objective of this work is to investigate the mechanical behavior of hybrid hemp/jute fibers reinforced epoxy composite material at liquid nitrogen temperature. Hemp and Jute fibers are used as reinforcement material as they have high specific strength, stiffness and good adhering property and has the potential to replace the synthetic fibers. Hybrid hemp/jute fibers reinforced polymer composite is prepared by hand lay-up method and test specimens are cut according to ASTM standards. These test specimens are dipped in liquid nitrogen for different time durations. The tensile properties, flexural properties and impact strength of the specimen are tested immediately after the specimens are removed from liquid nitrogen container. The experimental results indicate that the cryogenic treatment of the polymer composite has a significant effect on the mechanical properties of this material. The tensile properties and flexural properties of the hybrid hemp/jute fibers epoxy composite at liquid nitrogen temperature is higher than at room temperature. The impact strength of the material decreased after subjecting it to liquid nitrogen temperature.

Keywords: liquid nitrogen temperature, polymer composite, tensile properties, flexural properties

Procedia PDF Downloads 324

Authors: Mohamed M. Ibrahim, Gaber A. M. Mersal, Salih Al-Juaid, Samir A. El-Shazly

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A series of mixed ligand complexes, viz., [Cu(BPy)(Gly)X]Y {X = Cl (1), Y = 0; X = 0, Y = ClO4- (2); X = H2O, Y = NO3- (3); X = H2O, Y = CH3COO- (4); and [Cu(BPy)(Gly)-(H2O)]2(SO4) (5) have been synthesized. Their structures and properties were characterized by elemental analysis, thermal analaysis, IR, UV–vis, and ESR spectroscopy, as well as electrochemical measurements including cyclic voltammetry, electrical molar conductivity, and magnetic moment measurements. Complexes 1 and 2 formed slightly distorted square-pyramidal coordination geometries of CuN3OCl and CuN3O2, respectively in which the N,O-donor glycine and N,N-donor bipyridyl bind at the basal plane with chloride ion or water as the axial ligand. Complex 3 shows square planar CuN3O coordination geometry, which exhibits chemically significant hydrogen bonding interactions besides showing coordination polymer formation. The superoxide dismutase and catalase-like activities of all complexes were tested and were found to be promising candidates as durable electron-transfer catalyst being close to the efficiency of the mimicking enzymes displaying either catalase or tyrosinase activity to serve for complete reactive oxygen species (ROS) detoxification, both with respect to superoxide radicals and related peroxides. The DNA binding interaction with super coiled pGEM-T plasmid DNA was investigated by using spectral (absorption and emission) titration and electrochemical techniques. The results revealed that DNA intercalate with complexes 1 and 2 through the groove binding mode. The calculated intrinsic binding constant (Kb) of 1 and 2 were 4.71 and 2.429 × 105 M−1, respectively. Gel electrophoresis study reveals the fact that both complexes cleave super coiled pGEM-T plasmid DNA to nicked and linear forms in the absence of any additives. On the other hand, the interaction of both complexes with DNA, the quasi-reversible CuII/CuI redox couple slightly improves its reversibility with considerable decrease in current intensity. All the experimental results indicate that the bipyridyl mixed copper(II) complex (1) intercalate more effectively into the DNA base pairs.

Keywords: enzyme mimics, mixed ligand complexes, X-ray structures, antioxidant, DNA-binding, DNA cleavage

Procedia PDF Downloads 525

Authors: Rehana Akhter, Sajad A. Rather, F. A. Masoodi, Adil Gani, S. M. Wani

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During recent years probiotic food products receive market interest as health-promoting, functional foods, which are believed to contribute health benefits. In order to deliver the health benefits by probiotic bacteria, it has been recommended that they must be present at a minimum level of 106 CFU/g to 107 CFU/g at point of delivery or be eaten in sufficient amounts to yield a daily intake of 108 CFU. However a major challenge in relation to the application of probiotic cultures in food matrix is the maintenance of viability during processing which might lead to important losses in viability as probiotic cultures are very often thermally labile and sensitive to acidity, oxygen or other food constituents for example, salts. In this study Lactobacillus plantarum and Lactobacillus casei were encapsulated in calcium alginate beads with the objective of enhancing their survivability and preventing exposure to the adverse conditions of the gastrointestinal tract and where then inoculated in mutton nuggets. Micro encapsulated Lactobacillus plantarum and Lactobacillus casei were resistant to simulated gastric conditions (pH 2, 2h) and bile solution (3%, 2 h) resulting in significantly (p ≤ 0.05) improved survivability when compared with free cell counterparts. A high encapsulation yield was found due to the encapsulation procedure. After incubation at low pH-values, micro encapsulation yielded higher survival rates compared to non-encapsulated probiotic cells. The viable cell numbers of encapsulated Lactobacillus plantarum and Lactobacillus casei were 107-108 CFU/g higher compared to free cells after 90 min incubation at pH 2.5. The viable encapsulated cells were inoculated into mutton nuggets at the rate of 108 to 1010 CFU/g. The micro encapsulated Lactobacillus plantarum and Lactobacillus casei achieved higher survival counts (105-107 CFU/g) than the free cell counterparts (102-104 CFU/g). Thus micro encapsulation offers an effective means of delivery of viable probiotic bacterial cells to the colon and maintaining their survival during simulated gastric, intestinal juice and processing conditions during nugget preparation.

Keywords: survival, Lactobacillus plantarum, Lactobacillus casei, micro-encapsulation, nugget

Procedia PDF Downloads 263

Authors: Alexander García Mariaca, Rodrigo Morillo Castaño, Juan Rolón Ríos

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The government of Colombia has promoted the use of biofuels in the last 20 years through laws and resolutions, which regulate their use, with the objective to improve the atmospheric air quality and to promote Colombian agricultural industry. However, despite the use of blends of biofuels with fossil fuels, the air quality in large cities does not get better, this deterioration in the air is mainly caused by mobile sources that working with spark ignition internal combustion engines (SI-ICE), operating with a mixture in volume of 90 % gasoline and 10 % ethanol called E10, that for the case of Bogota represent 84 % of the fleet. Another problem is that Colombia has big cities located above 2200 masl and there are no accurate studies on the impact that the E10 mixture could cause in the emissions and performance of SI-ICE. This study aims to establish the optimal blend between gasoline ethanol in which an SI engine operates more efficiently in urban centres located at 2600 masl. The test was developed on SI engine four-stroke, single cylinder, naturally aspirated and with carburettor for the fuel supply using blends of gasoline and anhydrous ethanol in different ratios E10, E15, E20, E40, E60, E85 and E100. These tests were conducted in the city of Bogota, which is located at 2600 masl, with the engine operating at 3600 rpm and at 25, 50, 75 and 100% of load. The results show that the performance variables as engine brake torque, brake power and brake thermal efficiency decrease, while brake specific fuel consumption increases with the rise in the percentage of ethanol in the mixture. On the other hand, the specific emissions of CO2 and NOx present increases while specific emissions of CO and HC decreases compared to those produced by gasoline. From the tests, it is concluded that the SI-ICE worked more efficiently with the E40 mixture, where was obtained an increases of the brake power of 8.81 % and a reduction on brake specific fuel consumption of 2.5 %, coupled with a reduction in the specific emissions of CO2, HC and CO in 9.72, 52.88 and 76.66 % respectively compared to the results obtained with the E10 blend. This behaviour is because the E40 mixture provides the appropriate amount of the oxygen for the combustion process, which leads to better utilization of available energy in this process, thus generating a comparable power output to the E10 mixing and producing lower emissions CO and HC with the other test blends. Nevertheless, the emission of NOx increases in 106.25 %.

Keywords: emissions, ethanol, gasoline, engine, performance

Procedia PDF Downloads 312

Authors: Matt S. Van Deren, Michael Papenfus

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Seattle is one of the hundreds of cities in the United States that relies on a combined sewer system to collect and convey municipal wastewater. By design, these systems convey all wastewater, including industrial and commercial wastewater, human sewage, and stormwater runoff, through a single network of pipes. Serious problems arise for combined sewer systems during heavy precipitation events when treatment plants and storage facilities are unable to accommodate the influx of wastewater needing treatment, causing the sewer system to overflow into local waterways through sewer outfalls. CSOs (Combined Sewer Overflows) pose a serious threat to human and environmental health. Principal pollutants found in CSO discharge include microbial pathogens, comprising of bacteria, viruses, parasites, oxygen-depleting substances, suspended solids, chemicals or chemical mixtures, and excess nutrients, primarily nitrogen and phosphorus. While concentrations of these pollutants can vary between overflow events, CSOs have the potential to spread disease and waterborne illnesses, contaminate drinking water supplies, disrupt aquatic life, and effect a waterbody’s designated use. This paper estimates the economic impact of CSOs on residential property values. Using residential property sales data from Seattle, Washington, this paper employs a hedonic valuation model that controls for housing and neighborhood characteristics, as well as spatial and temporal effects, to predict a consumer’s willingness to pay for improved water quality near their homes. Initial results indicate that a 100,000-gallon decrease in the average annual overflow discharged from a sewer outfall within 300 meters of a home is associated with a 0.053% increase in the property’s sale price. For the average home in the sample, the price increase is estimated to be $18,860.23. These findings reveal some of the important economic benefits of improving water quality by reducing the frequency and severity of combined sewer overflows.

Keywords: benefits, hedonic, Seattle, sewer

Procedia PDF Downloads 149

Authors: Laura Mejias, Sandra Monteagudo, Oscar Martinez-Avila, Sergio Ponsa

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Bioplastics are gaining attention as potential substitutes of conventional fossil-derived plastics and new components of specialized applications in different industries. Besides, these constitute a sustainable alternative since they are biodegradable and can be obtained starting from renewable sources. Thus, agro-industrial wastes appear as potential substrates for bioplastics production using microorganisms, considering they are a suitable source for nutrients, low-cost, and available worldwide. Therefore, this approach contributes to the biorefinery and circular economy paradigm. The present study assesses the solid-state fermentation (SSF) technology for the co-synthesis of exopolysaccharides (EPS) and polyhydroxyalkanoates (PHA), two attractive biodegradable bioplastics, using the leftover of the brewery industry brewer's spent grain (BSG). After an initial screening of diverse PHA-producer bacteria, it was found that Burkholderia cepacia presented the highest EPS and PHA production potential via SSF of BSG. Thus, B. cepacia served to identify the most relevant aspects affecting the EPS+PHA co-synthesis at a lab-scale (100g). Since these are growth-dependent processes, they were monitored online through oxygen consumption using a dynamic respirometric system, but also quantifying the biomass production (gravimetric) and the obtained products (EtOH precipitation for EPS and solid-liquid extraction coupled with GC-FID for PHA). Results showed that B. cepacia has grown up to 81 mg per gram of dry BSG (gDM) at 30°C after 96 h, representing up to 618 times higher than the other tested strains' findings. Hence, the crude EPS production was 53 mg g-1DM (2% carbohydrates), but purity reached 98% after a dialysis purification step. Simultaneously, B. cepacia accumulated up to 36% (dry basis) of the produced biomass as PHA, mainly composed of polyhydroxybutyrate (P3HB). The maximum PHA production was reached after 48 h with 12.1 mg g⁻¹DM, representing threefold the levels previously reported using SSF. Moisture content and aeration strategy resulted in the most significant variables affecting the simultaneous production. Results show the potential of co-synthesis via SSF as an attractive alternative to enhance bioprocess feasibility for obtaining these bioplastics in residue-based systems.

Keywords: bioplastics, brewer’s spent grain, circular economy, solid-state fermentation, waste to product

Procedia PDF Downloads 124

Authors: Aiman Zehra, Sajad Mohd Wani

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Packaging has a vital role as it contains and protects the food that moves from the supply chain to the consumer. Chitosan (CH) has been extensively used in food packaging applications among the plentiful natural macromolecules, including all the polysaccharide class, owing to its easy film-forming capacity, biodegradability, better oxygen and water vapour barrier ability and good mechanical strength. Compared to synthetic films, the films produced from chitosan present poor barrier and mechanical properties. To overcome its deficient qualities, a number of modification procedures are required to enhance the mechanical and physical properties. Various additives such as plasticizers (e.g., glycerol and sorbitol), crosslinkers (e.g.,CaCl₂, ZnO), fillers (nanoclay), and antimicrobial agents (e.g. thyme essential oil) have been used to improve the mechanical, thermal, morphological, antimicrobial properties and emulsifying agents for the stability and elasticity of chitosan-based biodegradable films. Different novel biocomposite films based on chitosan incorporated with thyme essential oil and different additives (ZnO, CaCl₂, NC, and PEG) were successfully prepared and used as packaging material for carrot candy. The chitosan film incorporated with crosslinkers was capable of forming a protective barrier on the surface of the candy to maintain moisture content, water activity, TSS, total sugars, and titratable acidity. ZnO +PEG +NC +CaCl₂ remarkably promotes a synergistic effect on the barrier properties of the film. The combined use of ZnO +PEG +NC +CaCl₂ in CH-TO films was more effective in preventing the moisture gain in candies. The lowest a𝓌 (0.624) was also observed for the candies stored in treatment. The color values L*, a*, b* of the candies were also retained in the film containing all the additives during the 6th month of storage. The value for L*, a*, and b* observed for T was 42.72, 9.89, and 10.84, respectively. The candies packaged in film retained TSS and acidity. The packaging film significantly p≤0.05 conserved sensory qualities and inhibited microbial activity during storage. Carrot candy was found microbiologically safe for human consumption even after six months of storage in all the packaging materials.

Keywords: chitosan, biodegradable films, antimicrobial activity, thyme essential oil, crosslinkers

Procedia PDF Downloads 75

Authors: Adam Majczak, Michał Bialy, Zbigniew Czyż, Zdzislaw Kaminski

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Increasingly stringent emission standards for passenger cars require us to find alternative drives. The share of electric vehicles in the sale of new cars increases every year. However, their performance and, above all, range cannot be today successfully compared to those of cars with a traditional internal combustion engine. Battery recharging lasts hours, which can be hardly accepted due to the time needed to refill a fuel tank. Therefore, the ways to reduce the adverse features of cars equipped with electric motors only are searched for. One of the methods is a combination of an electric engine as a main source of power and a small internal combustion engine as an electricity generator. This type of drive enables an electric vehicle to achieve a radically increased range and low emissions of toxic substances. For several years, the leading automotive manufacturers like the Mazda and the Audi together with the best companies in the automotive industry, e.g., AVL have developed some electric drive systems capable of recharging themselves while driving, known as a range extender. An electricity generator is powered by a Wankel engine that has seemed to pass into history. This low weight and small engine with a rotating piston and a very low vibration level turned out to be an excellent source in such applications. Its operation as an energy source for a generator almost entirely eliminates its disadvantages like high fuel consumption, high emission of toxic substances, or short lifetime typical of its traditional application. The operation of the engine at a constant rotational speed enables a significant increase in its lifetime, and its small external dimensions enable us to make compact modules to drive even small urban cars like the Audi A1 or the Mazda 2. The algorithm to maintain a constant speed was investigated on the engine dynamometer with an eddy current brake and the necessary measuring apparatus. The research object was the Aixro XR50 rotary engine with the electronic power supply developed at the Lublin University of Technology. The load torque of the engine was altered during the research by means of the eddy current brake capable of giving any number of load cycles. The parameters recorded included speed and torque as well as a position of a throttle in an inlet system. Increasing and decreasing load did not significantly change engine speed, which means that control algorithm parameters are correctly selected. This work has been financed by the Polish Ministry of Science and Higher Education.

Keywords: electric vehicle, power generator, range extender, Wankel engine

Procedia PDF Downloads 136