Search results for: active medical implants

Authors: Najmeh Arabnejad, Mohammad Hossein Yousefi

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The risk of injuring is possible in most sports. These injuries are inevitable in contact sports. Since sports injuries result in financial, physical, physiological and social problems for most athletes and endanger their professional future, studying the happening of sports injuries in sports changes to an important issue. This study can be conducted through different aspects including psychological, pathological, social, managerial, etc. Therefore, the present study was designed and conducted with the aim Survey of Sports Injuries In Ten Sports from 2006 to 2011.This descriptive study was carried out in a documentary form. Thus, data related to sports insurance and sport injuries happened in soccer, volleyball, basketball, handball, badminton, karate, track and field, taekwondo, gymnastics and wrestling was collected from Sports Medical Board of Kerman Province, as the largest province in Iran, and then was analyzed. Data collection method was library one. Furthermore, information related to 210406 insured athletes was analyzed using Descriptive Statistical Indexes in the level mean and SPSS20 Software. The research findings showed that the number of male athletes who injured was higher than female athletes in most sports within various years. Soccer, karate, volleyball, wrestling, handball, taekwondo, gymnastics, basketball, track and field, and badminton had the most injuries, respectively. Moreover, the number of injured athletes and their ratio to insured ones during six years were studied; in general, an increase in ratio of sports injuries was observed. Thus, upward movement of sports injuries in different sports, as the results of this study confirm it, is a warning which results in losing young forces and wasting of sports potential in Iran.

Keywords: sports, sports injuries, survey, Kerman

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Authors: Lucy Ampaw-Asiedu, Terri R. Norton

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In the wake of recent disasters happening around the world such as earthquake in Italy (January, 2017); hurricanes in the United States (US) (September 2016 and September 2017); and compounding disasters in Haiti (September 2010 and September 2016); to our best knowledge, never has the world seen the need to work on preemptive rather than reactionary measures to salvage this situation than now. Tornadoes are natural hazards that mostly affect mid-western and central states in the US. Tornadoes, like all natural hazards such as hurricanes, earthquakes, floods and others, are very destructive and result in massive destruction to homes, cause billions of dollars in damage and claims many lives. Healthcare facilities in general are vulnerable to disasters, and therefore, the safety of patients, health workers and those who come in to seek shelter should be a priority. The focus of this study is to assess disaster management measures instituted by healthcare facilities. Thus, the sole aim of the study is to examine the vulnerabilities and the design of safe spaces in healthcare facilities in Central US. Objectives that guide the study are to primarily identify the impacts of tornadoes in hospitals and to assess the structural design or specifications of safe spaces. St. John’s Regional Medical Center, now Mercy Hospital in Joplin, is used as a case study. Preliminary results show that the lateral base shear of the proposed design to be 684.24 ton (1508.49kip) for the safe space. Findings from this work will be used to make recommendations about the design of safe spaces for health care facilities in Central US.

Keywords: disaster management, safe spaces, structural design, tornado, vulnerability

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Authors: G. Costa, F. Noto, L. Celona, F. Chines, G. Ciavola, G. Cuttone, S. Gammino, O. Leonardi, S. Marletta, G. Torrisi

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The ion sources for accelerators devoted to medical applications must provide intense ion beams, with high reproducibility, stability and brightness. AISHa (Advanced Ion Source for Hadron-therapy) is a compact ECRIS whose hybrid magnetic system consists of a permanent Halbach-type hexapole magnet and a set of independently energized superconducting coils. These coils will be enclosed in a compact cryostat with two cryocoolers for LHe-free operation. The AISHa ion source has been designed by taking into account the typical requirements of hospital-based facilities, where the minimization of the mean time between failures (MTBF) is a key point together with the maintenance operations which should be fast and easy. It is intended to be a multipurpose device, operating at 18 GHz, in order to achieve higher plasma densities. It should provide enough versatility for future needs of the hadron therapy, including the ability to run at larger microwave power to produce different species and highly charged ion beams. The source is potentially interesting for any hadrontherapy center using heavy ions. In the paper, we designed an innovative solution for the plasma containment chamber that allows us to solve our isolation and structural problems. We analyzed the materials chosen for our aim (glass fibers and carbon fibers) and we illustrated the all process (spinning, curing and machining) of the assembly of our chamber. The glass fibers and carbon fibers are used to reinforce polymer matrices and give rise to structural composites and composites by molding.

Keywords: hadron-therapy, carbon fiber, glass fiber, vacuum-bag, ECR, ion source

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Authors: Mangala Kohli, P. A. Athira, Reeha Mahajan

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The subthalamic nucleus (STN) is a biconvex nucleus situated in the diencephalon. The knowledge of the morphometry of the subthalamic nucleus is essential for accurate targeting of the nucleus during Deep Brain Stimulation. The present study aims to note the morphometry of the subthalamic nucleus in both the cerebral hemispheres which will prove to be of great value to radiologists and neurosurgeons. A cross‐sectional observational study was conducted in the Departments of Anatomy and Forensic Medicine, Lady Hardinge Medical College & Associated Hospitals, New Delhi on thirty adult cadaveric brain specimens of unclaimed and donated corpses. The specimens were categorized into 3 age groups: 20-35, 35-50 and above 50 years. All samples were collected after following the standard protocol for ethical clearance. The morphometric study of 60 subthalamic nucleus was thus conducted. Transverse section of the brain was made at a plane 4mm ventral to the plane containing mid commissural point. The dimensions of the subthalamic nucleus were measured bilaterally with the aid of digital Vernier caliper and magnifying glass. In the present study, the mean length and width and AC-PC length of the subthalamic nucleus was recorded on the right and left side in Group A, B and C. On comparison of mean of subthalamic nucleus dimensions between the right and left side in Group C, no statistically significant difference was observed. The length and width of subthalamic nucleus measured in the 3 age groups were compared with each other and the p value calculated. There was no statistically significant difference between the dimensions of Group A and B, Group B and C as well as Group A and C. The present study reveals that there is no significant reduction in the size of the nucleus was noted with increasing age. Thus, the values obtained in the present study can be used as a reference for various invasive and non-invasive procedures on subthalamic nucleus.

Keywords: cerebral hemisphere, deep brain stimulation, morphometry, subthalamic nucleus

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Authors: S. Saeed, T. Butt, M. Rehan, S. Khaliq

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Objective: To determine the frequency of pre-analytical errors in samples taken from patients for various lab tests at Fauji Foundation Hospital, Rawalpindi. Material and Methods: All the lab specimens for diagnostic purposes received at the lab from Fauji Foundation hospital, Rawalpindi indoor and outdoor patients were included. Total number of samples received in the lab is recorded in the computerized program made for the hospital. All the errors observed for pre-analytical process including patient identification, sampling techniques, test collection procedures, specimen transport/processing and storage were recorded in the log book kept for the purpose. Results: A total of 476616 specimens were received in the lab during the period of study including 237931 and 238685 from outdoor and indoor patients respectively. Forty-one percent of the samples (n=197976) revealed pre-analytical discrepancies. The discrepancies included Hemolyzed samples (34.8%), Clotted blood (27.8%), Incorrect samples (17.4%), Unlabeled samples (8.9%), Insufficient specimens (3.9%), Request forms without authorized signature (2.9%), Empty containers (3.9%) and tube breakage during centrifugation (0.8%). Most of these pre-analytical discrepancies were observed in samples received from the wards revealing that inappropriate sample collection by the medical staff of the ward, as most of the outdoor samples are collected by the lab staff who are properly trained for sample collection. Conclusion: It is mandatory to educate phlebotomists and paramedical staff particularly performing duties in the wards regarding timing and techniques of sampling/appropriate container to use/early delivery of the samples to the lab to reduce pre-analytical errors.

Keywords: pre analytical lab errors, tertiary care hospital, hemolyzed, paramedical staff

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Authors: Priyanka Dixit

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Reproductive health problem is an important public health issue in most of the developing countries like India. It is a common problem in India for women in the reproductive age group to suffer from reproductive illnesses and not seek care. Existing literatures tell us very little about the several dimensions of reproductive morbidity. In addition the general perception says, metros have better medical infrastructure, so its residents should lead a healthier life. However some of the studies reveal a very different picture. Therefore, the present study is conducted with the specific objectives to find out the prevalence of reproductive health problem and treatment seeking behavior of currently married women in four metro cities in India namely; Mumbai, Delhi, Chennai and Kolkata. In addition, this paper also examines the effect of socio-economic and demographic factors on self-reported reproductive health problems. Bi-variate and multivariate regression have been applied to achieve the proposed objectives. Study is based on National Family Health Survey 2015-16 data. The analysis shows that the prevalence of any reproductive health problem among women is the highest in Mumbai followed by Delhi, Chennai, and Kolkata. A bulk of women in all four metro cities has reported abdominal pain, itching and burning sensation as the major problems while urinating. However, in spite of the high prevalence of reproductive health problems, a huge proportion of such women in all these cities do not seek any advice or treatment for these problems. This study also investigates determinants that affect the prevalence of reproductive health problem to policy makers plan for proper interventions for improving women’s reproductive health.

Keywords: reproductive health, India, national family health survey-4, city

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Authors: Avi Shrivastava

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Title 42, an emergency health decree, has forced the federal authorities to turn away asylum seekers and all other border crossers since last year. When Title 42 was first deployed in immigration detention centers, where many migrants are held when they arrive at the U.S.-Mexico border, the Trump administration embraced it as a strategy. Expulsions Policy and New Border Challenges will be examined in regard to Title 42 concerns. Humanitarian measures for refugees arriving at the US-Mexico border are the focus of this article. To a large extent, this article addresses the implications of the United States' use of Title 42 in expelling refugees and the possible ramifications of doing away with it. A secondary data collecting strategy was used to gather the information for this study, allowing researchers to examine a large number of previously collected data sets. Information about Title 42 may be found in a variety of places, such as scholarly publications, newspapers, books, and the internet. The inquiry employed qualitative and explanatory research approaches. The claim that 1.7 million individuals were forced to leave the country as a result of it was withdrawn. Since CBP and ICE were limited in their ability to process deportees, it employed a very random patchwork technique in selecting the expelled individuals. As a consequence, repeat offenders, particularly those who were single, got a reduced punishment. The government will be compelled to focus on long-overdue but vital border enhancements if expulsions are halted. Title 42 provisions may help expedite the processing of asylum and other types of humanitarian relief. The government is prepared for an increase in arrivals, but ending the program would lead to a return to arrival levels seen during the Title 42 period.

Keywords: migrants, refugees, title 42, medical, trump administration

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Authors: Moses Aron, Elias Mwakilama, Jimmy Namangale

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Spending more time on long queues for a basic service remains a common challenge to most developing countries, including Malawi. For health sector in particular, Out-Patient Department (OPD) experiences long queues. This puts the lives of patients at risk. However, using queuing analysis to under the nature of the problems and efficiency of service systems, such problems can be abated. Based on a kind of service, literature proposes different possible queuing models. However, unlike using generalized assumed models proposed by literature, use of real time case study data can help in deeper understanding the particular problem model and how such a model can vary from one day to the other and also from each case to another. As such, this study uses data obtained from one urban HC for BP, Pediatric and General OPD cases to investigate an average queuing time for patients within the system. It seeks to highlight the proper queuing model by investigating the kind of distributions functions over patient’s arrival time, inter-arrival time, waiting time and service time. Comparable with the standard set values by WHO, the study found that patients at this HC spend more waiting times than service times. On model investigation, different days presented different models ranging from an assumed M/M/1, M/M/2 to M/Er/2. As such, through sensitivity analysis, in general, a commonly assumed M/M/1 model failed to fit the data but rather an M/Er/2 demonstrated to fit well. An M/Er/3 model seemed to be good in terms of measuring resource utilization, proposing a need to increase medical personnel at this HC. However, an M/Er/4 showed to cause more idleness of human resources.

Keywords: health care, out-patient department, queuing model, sensitivity analysis

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Authors: Rama Bhargava, Surabhi Nishad

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The infusion of nanofluids has dramatically enhanced the heat-carrying capacity of the fluids, applicable to many engineering and medical process where the temperature below freezing is required. Cryosurgery is an efficient therapy for the treatment of cancer, but sometimes the excessive cooling may harm the nearby healthy cells. Efforts are therefore done to develop a model which can cause to generate the low temperature as required. In the present study, a mathematical model is developed based on the bioheat transfer equation to simulate the heat transfer from the probe on a tumor (with irregular domain) using the hybrid technique consisting of element free Galerkin method with αα-family of approximation. The probe is loaded will nano-particles. The effects of different nanoparticles, namely Al₂O₃, Fe₃O₄, Au on the heat-producing rate, is obtained. It is observed that the temperature can be brought to (60°C)-(-30°C) at a faster freezing rate on the infusion of different nanoparticles. Besides increasing the freezing rate, the volume of the nanoparticle can also control the size and growth of ice crystals formed during the freezing process. The study is also made to find the time required to achieve the desired temperature. The problem is further extended for multi tumors of different shapes and sizes. The irregular shape of the frozen domain and the direction of ice growth are very sensitive issues, posing a challenge for simulation. The Meshfree method has been one of the accurate methods in such problems as a domain is naturally irregular. The discretization is done using the nodes only. MLS approximation is taken in order to generate the shape functions. Sufficiently accurate results are obtained.

Keywords: cryosurgery, EFGM, hybrid, nanoparticles

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Authors: Bhavatharani S., Boopathy V., Kavin S., Naveethkumar R.

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Context: Resistance training with blood flow restriction (BFR) has increased in clinical rehabilitation due to the substantial benefits observed in augmenting muscle mass and strength using low loads. However, there is a great variability of training pressures for clinical populations as well as methods to estimate it. The aim of this study was to estimate the percentage of maximal BFR that could result by applying different methodologies based on arbitrary or individual occlusion levels using a cuff width between 9 and 13 cm. Design: A secondary analysis was performed on the combined databases of 2 previous larger studies using BFR training. Methods: To estimate these percentages, the occlusion values needed to reach complete BFR (100% limb occlusion pressure [LOP]) were estimated by Doppler ultrasound. Seventy-five participants (age 24.32 [4.86] y; weight: 78.51 [14.74] kg; height: 1.77 [0.09] m) were enrolled in the laboratory study for measuring LOP in the thigh, arm, or calf. Results: When arbitrary values of restriction are applied, a supra-occlusive LOP between 120% and 190% LOP may result. Furthermore, the application of 130% resting brachial systolic blood pressure creates a similar occlusive stimulus as 100% LOP. Conclusions: Methods using 100 mm Hg and the resting brachial systolic blood pressure could represent the safest application prescriptions as they resulted in applied pressures between 60% and 80% LOP. One hundred thirty percent of the resting brachial systolic blood pressure could be used to indirectly estimate 100% LOP at cuff widths between 9 and 13 cm. Finally, methodologies that use standard values of 200 and, 300 mm Hg far exceed LOP and may carry additional risk during BFR exercise.

Keywords: lower limb rehabilitation, ESP32, pneumatics for medical, programmed rehabilitation

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Authors: Sumit Kumar Das, Laishram Ladusingh

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Aim: The aim of the study is to examine the differential of epidemiological transition across fifteen agro-climatic zones of India and its effect on health-seeking behavior. Data and Methods: Unit level data on consumption expenditure on health of India from three decadal rounds conducted by National Sample Survey Organization are used for the analysis. These three rounds are 52nd (1995-96), 60th (2004-05) and 71st (2014-15). The age-adjusted prevalence rate for communicable diseases and non-communicable diseases are estimated for fifteen agro-climatic zones of India for three time periods. Bivariate analysis is used to find out determinants of health-seeking behavior. Multilevel logistic regression is used to examine factors effecting on household health-seeking behavior. Result: The prevalence of communicable diseases is increasing in most of the zones of India. Every South Indian zones, Gujarat plains, and lower Gangetic plain are facing the severe attack of dual burden of diseases. Demand for medical advice has increased in southern zones, and east zones, reliance on private healthcare facilities are increasing in most of the zone. Demographic characteristics of the household head have a significant impact on health-seeking behavior. Conclusion: Proper program implementation is required considering the disease prevalence and differential in the pattern of health seeking behavior. Along with initiation and strengthening of programs for non-communicable, existing programs for communicable diseases need to monitor and supervised strictly.

Keywords: agro-climatic zone, epidemiological transition, health-seeking behavior, multilevel regression

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Authors: Valentina Narvaez Gaitan, Paula K. Rodriguez Ramirez, Derian D. Espinosa

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Corrective orthosis has great importance in orthopedic treatments providing assistance in improving mobility and stability in order to improve the quality of life for a different patient. The corrective orthosis studied in this article can correct deformities, reduce pain, and improve the ability to perform daily activities. This work describes the design and evaluation of a corrective orthosis for knee hyperextension. This orthosis is capable of generating a progressive and variable alignment of the joint, limiting the range of motion according to medical criteria. The main objective was to design a corrective knee orthosis capable of correcting knee hyperextension progressively to return to its natural angle with greater economic affordability and adjustable size. The limiting mechanism is based on a goniometer to determine the desired angles. The orthosis was made of acrylic to reduce costs and maintenance; neoprene is also used to make comfortable contact; additionally, Velcro was used in order to adjust the orthosis for various sizes. Simulations of static and fatigue analysis of the mechanism were performed to verify its resistance and durability under normal conditions. A biomechanical gait study of gait was carried out on 10 healthy subjects without the orthosis and limiting their knee extension capacity in a normal gait cycle with the orthosis to observe the efficiency of the proposed system. In the results obtained, the knee angle curves show that the maximum extension angle was the established angle by the orthosis. Showing the efficiency of the proposed design for different leg sizes.

Keywords: biomechanical study, corrective orthosis, efficiency, goniometer, knee hyperextension.

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Authors: A. Kaeotawee, N. Bunmas, W. Chomthong

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Background: The cancellation of elective surgery is a major indicator of poor operating room efficiency. Furthermore, it is recognized as a major cause of emotional trauma to patients as well as their families. This study was carried out to assess the incidence and causes of elective surgery cancellation in our setting and to find the appropriate solutions for better quality management. Objective: To determine the incidence and causes of elective surgery cancellations in Songklanagarind Hospital. Material and Method: A prospective survey was conducted from September to November 2012. All patients who had their scheduled elective operations cancelled were assessed. Data was collected on the following 2 components: (1) patient demographics;(2) main reasons for cancellations, which were grouped into patient-related factors and organizational-related factors. Data are reported as a percentage of patients whose operations were cancelled. The association between cancellation status and patient demographics was assessed using univariate logistic regression. Results: 2,395 patients were scheduled for elective surgery and of these 343 (14.3%) had their operations cancelled. Cardiothoracic surgery had the highest rate of cancellations (28.7%) while the least number of cancellations occurred in ophthalmology (10.1%). The main reasons for cancellations were related to the unit's organization (53.6%), due to the surgeon (48.4%). Patient related causes (46.4%), due to non medical reasons (32.1%). The most common cause of cancellation by the surgeon was lack of theater time (21.3%), by patients due to the patient’s nonappearance (25.1%). Cancellation was significantly associated with type of patient, health insurance, type of anesthesia and specialties (p<0.05). Conclusion: Surgery cancellations by surgeons relating to a lack of theater time was a significant problem in our setting. Appropriate solutions for better quality improvement are needed.

Keywords: elective cases, surgery cancellation, quality management, appropriate solutions

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Authors: Zsanett Bahor, Cristina Nunes-Fonseca, Gillian L. Currie, Emily S. Sena, Lindsay D.G. Thomson, Malcolm R. Macleod

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Psychosis is ranked as the third most disabling medical condition in the world by the World Health Organization. Despite a substantial amount of research in recent years, available treatments are not universally effective and have a wide range of adverse side effects. Since many clinical drug candidates are identified through in vivo modelling, a deeper understanding of these models, and their strengths and limitations, might help us understand reasons for difficulties in psychosis drug development. To provide an unbiased summary of the preclinical psychosis literature we performed a systematic electronic search of PubMed for publications modelling a psychotic disorder in vivo, identifying 14,721 relevant studies. Double screening of 11,000 publications from this dataset so far established 2403 animal studies of psychosis, with the most common model being schizophrenia (95%). 61% of these models are induced using pharmacological agents. For all the models only 56% of publications test a therapeutic treatment. We propose a systematic review of these studies to assess the prevalence of reporting of measures to reduce risk of bias, and a meta-analysis to assess the internal and external validity of these animal models. Our findings are likely to be relevant to future preclinical studies of psychosis as this generation of strong empirical evidence has the potential to identify weaknesses, areas for improvement and make suggestions on refinement of experimental design. Such a detailed understanding of the data which inform what we think we know will help improve the current attrition rate between bench and bedside in psychosis research.

Keywords: animal models, psychosis, systematic review, schizophrenia

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Authors: Sajeli A. Begum, Ameer Basha, Kirti Hira, Rukaiyya Khan

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Cyclic dipeptides are simple diketopiperazine derivatives being investigated by several scientists for their biological effects which include anticancer, antimicrobial, haematological, anticonvulsant, immunomodulatory effect, etc. They are potentially active microbial metabolites having been synthesized too, for developing into drug candidates. Cultures of Pseudomonas species have earlier been reported to produce cyclic dipeptides, helping in quorum sensing signals and bacterial–host colonization phenomena during infections, causing cell anti-proliferation and immunosuppression. Fluorescing Pseudomonas species have been identified to secrete lipid derivatives, peptides, pyrroles, phenazines, indoles, aminoacids, pterines, pseudomonic acids and some antibiotics. In the present work, results of investigation on the cyclic dipeptide metabolites secreted by the culture broth of Pseudomonas species as potent pro-inflammatory cytokine inhibitors are discussed. The bacterial strain was isolated from the rhizospheric soil of groundnut crop and identified as Pseudomonas aeruginosa by 16S rDNA sequence (GenBank Accession No. KT625586). Culture broth of this strain was prepared by inoculating into King’s B broth and incubating at 30 ºC for 7 days. The ethyl acetate extract of culture broth was prepared and lyophilized to get a dry residue (EEPA). Lipopolysaccharide (LPS)-induced ELISA assay proved the inhibition of tumor necrosis factor-alpha (TNF-α) secretion in culture supernatant of RAW 264.7 cells by EEPA (IC50 38.8 μg/mL). The effect of oral administration of EEPA on plasma TNF-α level in rats was tested by ELISA kit. The LPS mediated plasma TNF-α level was reduced to 45% with 125 mg/kg dose of EEPA. Isolation of the chemical constituents of EEPA through column chromatography yielded ten cyclic dipeptides, which were characterized using nuclear magnetic resonance and mass spectroscopic techniques. These cyclic dipeptides are biosynthesized in microorganisms by multifunctional assembly of non-ribosomal peptide synthases and cyclic dipeptide synthase. Cyclo (Gly-L-Pro) was found to be more potentially (IC50 value 4.5 μg/mL) inhibiting TNF-α production followed by cyclo (trans-4-hydroxy-L-Pro-L-Phe) (IC50 value 14.2 μg/mL) and the effect was equal to that of standard immunosuppressant drug, prednisolone. Further, the effect was analyzed by determining mRNA expression of TNF-α in LPS-stimulated RAW 264.7 macrophages using quantitative real-time reverse transcription polymerase chain reaction. EEPA and isolated cyclic dipeptides demonstrated diminution of TNF-α mRNA expression levels in a dose-dependent manner under the tested conditions. Also, they were found to control the expression of other pro-inflammatory cytokines like IL-1β and IL-6, when tested through their mRNA expression levels in LPS-stimulated RAW 264.7 macrophages under LPS-stimulated conditions. In addition, significant inhibition effect was found on Nitric oxide production. Further all the compounds exhibited weak toxicity to LPS-induced RAW 264.7 cells. Thus the outcome of the study disclosed the effectiveness of EEPA and the isolated cyclic dipeptides in down-regulating key cytokines involved in pathophysiology of autoimmune diseases.In another study led by the investigators, microbial cyclic dipeptides were found to exhibit excellent antimicrobial effect against Fusarium moniliforme which is an important causative agent of Sorghum grain mold disease. Thus, cyclic dipeptides are emerging small molecular drug candidates for various autoimmune diseases.

Keywords: cyclic dipeptides, cytokines, Fusarium moniliforme, Pseudomonas, TNF-alpha

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Authors: Papakonstantinou Apostolos, Argyrios Moustakas, Panagiotis Zervos, Dimitrios Stefanakis, Manolis Tsapakis, Nektarios Spyridakis, Mary Paspaliari, Christos Kontos, Antonis Legakis, Sarantis Houzouris, Konstantinos Topouzelis

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For years unmanned and remotely operated robots have been used as tools in industry research and education. The rapid development and miniaturization of sensors that can be attached to remotely operated vehicles in recent years allowed industry leaders and researchers to utilize them as an affordable means for data acquisition in air, land, and sea. Despite the recent developments in the ground and unmanned airborne vehicles, a small number of Unmanned Surface Vehicle (USV) platforms are targeted for mapping and monitoring environmental parameters for research and industry purposes. The ARGO project is developed an open-design USV equipped with multi-level control hardware architecture and state-of-the-art sensors and payloads for the autonomous monitoring of environmental parameters in large sea areas. The proposed USV is a catamaran-type USV controlled over a wireless radio link (5G) for long-range mapping capabilities and control for a ground-based control station. The ARGO USV has a propulsion control using 2x fully redundant electric trolling motors with active vector thrust for omnidirectional movement, navigation with opensource autopilot system with high accuracy GNSS device, and communication with the 2.4Ghz digital link able to provide 20km of Line of Sight (Los) range distance. The 3-meter dual hull design and composite structure offer well above 80kg of usable payload capacity. Furthermore, sun and friction energy harvesting methods provide clean energy to the propulsion system. The design is highly modular, where each component or payload can be replaced or modified according to the desired task (industrial or research). The system can be equipped with Multiparameter Sonde, measuring up to 20 water parameters simultaneously, such as conductivity, salinity, turbidity, dissolved oxygen, etc. Furthermore, a high-end multibeam echo sounder can be installed in a specific boat datum for shallow water high-resolution seabed mapping. The system is designed to operate in the Aegean Sea. The developed USV is planned to be utilized as a system for autonomous data acquisition, mapping, and monitoring bathymetry and various environmental parameters. ARGO USV can operate in small or large ports with high maneuverability and endurance to map large geographical extends at sea. The system presents state of the art solutions in the following areas i) the on-board/real-time data processing/analysis capabilities, ii) the energy-independent and environmentally friendly platform entirely made using the latest aeronautical and marine materials, iii) the integration of advanced technology sensors, all in one system (photogrammetric and radiometric footprint, as well as its connection with various environmental and inertial sensors) and iv) the information management application. The ARGO web-based application enables the system to depict the results of the data acquisition process in near real-time. All the recorded environmental variables and indices are presented, allowing users to remotely access all the raw and processed information using the implemented web-based GIS application.

Keywords: monitor marine environment, unmanned surface vehicle, mapping bythometry, sea environmental monitoring

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Authors: G. M. Contessa, L. Lepore, G. Gandolfo, C. Poggi, N. Cherubini, R. Remetti, S. Sandri

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Practical guidelines are provided in this work for the safe use of a portable d-t Thermo Scientific MP-320 neutron generator producing pulsed 14.1 MeV neutron beams. The neutron generator’s emission was tested experimentally and reproduced by MCNPX Monte Carlo code. Simulations were particularly accurate, even generator’s internal components were reproduced on the basis of ad-hoc collected X-ray radiographic images. Measurement campaigns were conducted under different standard experimental conditions using an LB 6411 neutron detector properly calibrated at three different energies, and comparing simulated and experimental data. In order to estimate the dose to the operator vs. the operating conditions and the energy spectrum, the most appropriate value of the conversion factor between neutron fluence and ambient dose equivalent has been identified, taking into account both direct and scattered components. The results of the simulations show that, in real situations, when there is no information about the neutron spectrum at the point where the dose has to be evaluated, it is possible - and in any case conservative - to convert the measured value of the count rate by means of the conversion factor corresponding to 14 MeV energy. This outcome has a general value when using this type of generator, enabling a more accurate design of experimental activities in different setups. The increasingly widespread use of this type of device for industrial and medical applications makes the results of this work of interest in different situations, especially as a support for the definition of appropriate radiation protection procedures and, in general, for risk analysis.

Keywords: instrumentation and monitoring, management of radiological safety, measurement of individual dose, radiation protection of workers

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Authors: Amna bibi, Hina Rana

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In the social, behavioral, and medical sciences, and particularly in Pakistani popular culture and political discourse, transgender issues are a relatively recent subject of research. The present study aimed to explore the lived experiences related to psycho-social issues faced by transgenders in Pakistani society. In this qualitative study, phenomenology research design was used. The purposive and snowball sampling techniques were used for data collection and in-depth interviews were conducted with N= 8 transgenders belonging to Lahore city, Pakistan. All interviews were audio recorded and transcribed properly. Interpretative phenomenological analysis was used to generate results in terms of themes. The results of the current study revealed different major themes such as psychological, social, and financial problems. Several emergent and sub-themes were also generated such as insomnia, suicidal ideation, stress, physical abuse, social rejection, discrimination at work workplace, less job opportunities, and harassment. Current study indicate that transgender suffer from different problems and struggle hard for their daily living. It was concluded that there should be a step taken at government level for the betterment of this community. The findings of the present study can help out transgender communities and activist to uncover their problem and empowering transgender individuals through education, skill development, and opportunities for growth. Their abilities can be utilized by providing education, polishing their skills, and employment opportunities. The data provides the knowledge that there should be strategies at family, society and government level for the betterment of transgenders.

Keywords: psychological issues, social issues, financial issues, transgender, Pakistani society

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Authors: Amna Bibi, Hina Rana

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In the social, behavioral, and medical sciences, and particularly in Pakistani popular culture and political discourse, transgender issues are a relatively recent subject of research. The present study aimed to explore the lived experiences related to psycho-social issues faced by transgenders in Pakistani society. In this qualitative study, phenomenology research design was used. The purposive and snowball sampling techniques were used for data collection and in-depth interviews were conducted with N= 8 transgenders belonging to Lahore city, Pakistan. All interviews were audio recorded and transcribed properly. Interpretative phenomenological analysis was used to generate results in terms of themes. The results of the current study revealed different major themes such as psychological, social, and financial problems. Several emergent and sub-themes were also generated such as insomnia, suicidal ideation, stress, physical abuse, social rejection, discrimination at work workplace, less job opportunities, and harassment. Current study indicate that transgender suffer from different problems and struggle hard for their daily living. It was concluded that there should be a step taken at government level for the betterment of this community. The findings of the present study can help out transgender communities and activist to uncover their problem and empowering transgender individuals through education, skill development, and opportunities for growth. Their abilities can be utilized by providing education, polishing their skills, and employment opportunities. The data provides the knowledge that there should be strategies at family, society and government level for the betterment of transgenders.

Keywords: psychological issues, social issues, financial issues, transgender, Pakistani society

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Authors: Selam Mulugeta, Barkot Milkias, Mesfin Araya, Abel Worku, Eyasu Mulugeta

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In Ethiopia, there is inadequate information on non-adherence to antidepressant treatment in patients with depressive disorders. Having awareness of the pattern of adherence is important in future prognosis, quality of life, and functionality in these patients. This hospital-based cross-sectional quantitative study was done on a sample of 216 consecutive outpatients with depressive disorders. Data were collected using questionnaires through in-person and phone call interviews. The 8-item Morisky scale was used to assess the pattern of medication adherence. Other specially developed tools were used to obtain sociodemographic and clinical information from electronic medical records and patient interviews. Data were analyzed using the Statistical Package for the Social Sciences Version - 25. Univariate and multivariable analyses were carried out to assess factors associated with non-adherence. 90% of the participants had a primary diagnosis of major depressive disorder. Based on the 8-item Morisky Medication Adherence Scale, the prevalence of non-adherence was found to be 84.7%. Living distance between 11 to 50 km from the hospital (AOR= 11, 95% CI (29,46.6)), post-secondary level of education (AOR= 8.3, 95% CI (1, 64.4)) and taking multiple medications (AOR= 6.1, 95% CI (1, 34.9)) were found to have significantly increased odds of non-adherence. Non-adherence was significantly associated with factors such as increased living distance from the hospital, relatively higher educational level, and polypharmacy. Proper and patient-centered psychoeducation, addressing the communication gap between patients and doctors, adherence to prescribing guidelines, avoiding polypharmacy unless indicated & working on accessibility of treatment is essential to decrease non-adherence.

Keywords: depressive disorders, Ethiopia, medication adherence, Addis Ababa

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Authors: Pei-Fan Mu

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Background: Lung cancer is the most common cancer with the highest mortality rate. Patients with lung cancer under chemotherapy treatment experience life-threatening uncertainty. This study was based on the broaden-and-build theory using intentionality reflection of the body and internalization of positive prioritization strategies to enhance positive emotions of patients with lung cancer. Purpose: The purpose of this study was to use a quasi-experimental research design to examine the effectiveness of the enhancing positive emotion program. Method: Data were collected from a medical center in Taiwan. Fifty-four participants with lung cancer were recruited. Thirty participants were in the experiential group receiving the two weeks program. The content of the program includes awareness and understanding of the symptom experience, co-existing with illness and establishing self-identity, cognitive-emotion adjustment and establishing a new body schema, and symptom management to reach spiritual well-being. Twenty-four participants were in the control group receiving regular nursing care. Baseline, one month later and two months later, programmed measurements of symptoms of distress, positive emotion, and psychological well-being. Results: These two weeks of enhancing the positive emotion program resulted in a significantly improved positive emotion score for the experimental group compared to the control group. The findings of this study indicated that the positive emotion had significant differences between the two groups. There were no differences in symptom distress between the two groups. Discussion: The findings indicated that the enhancing positive emotion program could help patients enhance their life-threatening facing conditions.

Keywords: positive emotion, lung cancer, experimental design, symptom distress

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Authors: Hsiu-Chuan Hsueh, Kuei-Feng Shen Jr., Chia-Ling Chao, Hui-Chuan Pan

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This article described a 75 years old woman who has suffered from intestinal perforation and accepted surgery with temporary enterostomy, the operation makes her depressed, refused relatives and friend's care, facing low willingness to participate in various activities due to fear of changing body appearance caused by surgery and leave enterostomy. The author collected information through observation talks, physical evaluation, and medical records during the period of care from November 14 to November 30, 2016, we used the four aspects of physiology, psychology, society and spirituality as a whole sexual assessment to establish the nursing problems of patient, included of acute pain, disturbance of body image,coping ineffective individual. For patient care issues, to encouraged case to express their inner feelings and take part in self-care programs through providing good therapeutic interpersonal relationships with their families. However, it provided clear information about the disease and follow-up treatment plan, give compliments in a timely manner, enhanced self-confidence of individual cases and their motivation to participate in self-care of stoma, further face the disease in a positive manner. At the same time, cross-section team care model and individual care measures were developed to enhance the care skills after returning home and at the same time assist the individual in facing the psychological impact caused by stoma. Hope to provide this experience, as a reference for the future care of the disease.

Keywords: enterostomy, intestinal perforation, nursing experience, ostomy

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Authors: Adila Shaukat, Hussam Al Soub, Muna Al Maslamani, Abdullatif Al Khal

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Background: The aim of this study was to assess clinical presentation and antimicrobial susceptibility of Streptococcus (S.) anginosus group infections in Hamad General Hospital, a tertiary care hospital in the state of Qatar, which is a multinational community. The S. anginosus group is a subgroup of viridans streptococci that consist of 3 different species: S. anginosus, S. constellatus, and S. intermedius. Although a part of the human bacteria flora, they have potential to cause suppurative infections. Method: We studied a total of 101 patients with S. anginosus group infections from January 2006 until March 2012 by reviewing medical records and identification of organisms by VITEK 2 and MALDI-TOF. Results: The most common sites of infection were skin and soft tissue, intra-abdominal, and bacteremia (28.7%, 24.8%, and 22.7%, respectively). Abscess formation was seen in approximately 30% of patients. Streptococcus constellatus was the most common isolated species (40%) followed by S. anginosus(30%) and S. intermedius(7%). In 23% of specimens, the species was unidentified. The most common type of specimen for organism isolation was blood followed by pus and tissue (50%, 22%, and 8%, respectively). Streptococcus constellatus was more frequently associated with abdominal and skin and soft tissue infections than the other 2 species, whereas S. anginosus was isolated more frequently from blood. All isolates were susceptible to penicillin, ceftriaxone, and vancomycin. Susceptibility to erythromycin and clindamycin was also good, reaching 91% and 95%, respectively. Forty percent of patients needed surgical drainage along with antibiotic therapy. Conclusions: Identification of S. anginosus group to species level is helpful in clinical practice because different species exhibit different pathogenic potentials.

Keywords: abscess, bacterial infection, bacteremia, Streptococcus anginosus

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Authors: Khaleel Alyahya, Faizah Alotaibi

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The coronavirus disease 19 (COVID-19) pandemic has caused an increase in general fear and anxiety around the globe. With the public health measures, including lockdown and travel restrictions, the COVID-19 period further resulted in a sudden increase in the vulnerability of people too ill mental health. This becomes greater among individuals who have a history of mental illness or are undergoing treatment and do not have easy access to medication and medical consultations. The study aims to measure the impact of COVID-19 and the degree of distress with the DASS scale on the mental health of residents living in Saudi Arabia. The study is a quantitative, observational, and cross-sectional conducted in Saudi Arabia to measure the impact of COVID-19 on the mental health of both citizens and residents of Saudi Arabia during pandemics. The study ran from February 2021 to June 2021, and a validated questionnaire was used. The targeted population of the study was Saudi citizens and non-Saudi residents. A sample size of 800 participants was calculated with a single proportion formula at 95% level of significance and 5% allowable error. The result revealed that participants who were always doing exercise experienced the lowest level of depression, anxiety, and stress. The highest prevalence of severe and extremely severe depression was among participants who sometimes do exercise at 53.2% for each. Similar results were obtained for anxiety and stress, where the extremely severe form was reported by those who sometimes did exercise at 54.8% and 72.2%, respectively. There was an inverse association between physical activity levels and levels of depression, anxiety, and stress during the COVID-19. Similarly, the levels of depression, anxiety, and stress differed significantly according to the exercise frequency during COVID-19.

Keywords: mental, COVID-19, pandemic, lockdown, depression, anxiety, stress

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Authors: Ngawang Tsering

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Traditional Tibetan medicine is primarily focused on promoting health and keeping away diseases from its unique in prescribing specific diet and lifestyle. The prevalence of chronic diseases has been rising day by day and kills a number of people due to the lack of proper nutritional design in modern times. According to traditional Tibetan medicine, chronic diseases such as diabetes, cancer, cardiovascular diseases, respiratory diseases, and arthritis are heavily associated with an unwholesome diet and inappropriate lifestyles. Diet and lifestyles are the two main conditions of diseases and healthy life. The prevalence of chronic diseases is one of the challenges, with massive economic impact and expensive health issues. Though chronic diseases are challenges, it has a solution in the preventive measurements by using proper nutrition design based on traditional Tibetan medicine. Until today, it is hard to evaluate whether traditional Tibetan medicine nutrition strategy could play a major role in preventive measurement as of the lack of current research evidence. However, compared with modern nutrition, it has an exclusive valuable concept, such as a holistic way and diet or nutrition recommendation based on different aspects. Traditional Tibetan medicine is one of the oldest ancient existing medical systems known as Sowa Rigpa (Science of Healing) highlights different aspects of dietetics and nutrition, namely geographical, seasonal, age, personality, emotional, food combination, the process of individual metabolism, potency, and amount of food. This article offers a critical perspective on the preventive measurement against chronic diseases through nutrition design using traditional Tibetan medicine and also needs attention for a deeper understanding of traditional Tibetan medicine in the modern world.

Keywords: traditional Tibetan medicine, nutrition, chronic diseases, preventive measurement, holistic approach, integrative

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Authors: Priscilla Adoley Moffat

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This study explored perceptions rooted in and acquired from the cultures of many developing countries and how they impact applicants’ preferences and choices of STEM programs. The context of developing countries was chosen for this study because gender role socialization continues to maintain an important place in most of these cultures. This study’s relevance rests in the fact that, as the world takes steps to encourage and promote the choice and study of STEM programs, especially among females, there is a need for efforts towards understanding various cultural perceptions towards some programs of study, particularly STEM programs, which have diverse gender attributions in many developing cultures. Also, as the world strives to achieve gender equity in education, such a study comes in handy, as it provides a useful understanding of the underlying cultural factors that affect study program preferences of applicants, particularly in developing countries like Ghana as well as others in Africa. The study analyzed the admission application data of five public universities in Ghana. 1600 randomly-sampled final-year students of 32 randomly-selected senior high schools from the 16 regions of Ghana were interviewed. Since parents and teachers often guide and influence the study program choices of applicants, the study examined the perceptions of 180 teachers and 360 parents. The study found, among other things, that STEM programs are commonly perceived to pose much more difficulty to females than they do to males. As a result, many female applicants are discouraged from choosing these programs. While nursing programs are perceived more as programs for females, with the justification that females are better caregivers, males are perceived to be better medical doctors, engineers, and computer technicians. Thus, many females are less encouraged to choose Technology and Engineering programs.

Keywords: culture, perceptions, STEM, choice, preference

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Authors: Michelle C. S. Azevedo, Priscila M. Colavite, Carolina F. Francisconi, Ana P. Trombone, Gustavo P. Garlet

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VIP (vasoactive intestinal peptide) know as a potential protective factor in the view of its marked immunosuppressive properties. In this work, we investigated a possible association of VIP with the clinical status of experimental periapical granulomas and the association with expression markers in the lesions potentially associated with periapical lesions pathogenesis. C57BL/6WT mice were treated or not with recombinant VIP. Animals with active/progressive (N=40), inactive/stable (N=70) periapical granulomas and controls (N=50) were anesthetized and the right mandibular first molar was surgically opened, allowing exposure of dental pulp. Endodontic pathogenic bacterial strains were inoculated: Porphyromonas gingivalis, Prevotella nigrescens, Actinomyces viscosus, and Fusobacterium nucleatum subsp. polymorphum. The cavity was not sealed after bacterial inoculation. During lesion development, animals were treated or not with recombinant VIP 3 days post infection. Animals were killed after 3, 7, 14, and 21 days of infection and the jaws were dissected. The extraction of total RNA from periodontal tissues was performed and the integrity of samples was checked. qPCR reaction using TaqMan chemistry with inventoried primers were performed in ViiA7 equipment. The results, depicted as the relative levels of gene expression, were calculated in reference to GAPDH and β-actin expression. Periodontal tissues from upper molars were vested and incubated supplemented RPMI, followed by processing with 0.05% DNase. Cell viability and couting were determined by Neubauer chamber analysis. For flow cytometry analysis, after cell counting the cells were stained with the optimal dilution of each antibody; (PE)-conjugated and (FITC)-conjugated antibodies against CD4, CD25, FOXP3, IL-4, IL-17 and IFN-γ antibodies, as well their respective isotype controls. Cells were analyzed by FACScan and CellQuest software. Results are presented as the number of cells in the periodontal tissues or the number of positive cells for each marker in the CD4+FOXp3+, CD4+IL-4+, CD4+IFNg+ and CD4+IL-17+ subpopulations. The levels mRNA were measured by qPCR. The VIP expression was predominated in inactive lesions, as well part of the clusters of cytokine/Th markers identified as protective factors and a negative correlation between VIP expression and lesion evolution was observed. A quantitative analysis of IL1β, IL17, TNF, IFN, MMP2, RANKL, OPG, IL10, TGFβ, CTLA4, COL5A1, CTGF, CXCL11, FGF7, ITGA4, ITGA5, SERP1 and VTN expression was measured in experimental periapical lesions treated with VIP 7 and 14 days after lesion induction and healthy animals. After 7 days, all targets presented a significate increase in comparison to untreated animals. About migration kinetics, profile of chemokine receptors expression of TCD4+ subsets and phenotypic analysis of Tregs, Th1, Th2 and Th17 cells during the course of experimental periodontal disease evaluated by flow cytometry and depicted as the number of positive cells for each marker. CD4+IFNg+ and CD4+FOXp3+ cells migration were significate increased 7 days post VIP treatment. CD4+IL17+ cells migration were significate increased 7 and 14 days post VIP treatment, CD4+IL4+ cells migration were significate increased 14 and 21 days post VIP treatment compared to the control group. In conclusion, our experimental data support VIP involvement in determining the inactivity of periapical lesions. Financial support: FAPESP #2015/25618-2.

Keywords: chronic inflammation, cytokines, osteolytic lesions, VIP (Vasoactive Intestinal Peptide)

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Authors: Fahad Abbasi

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Flow of electrically conducting nanofluids is of pivotal importance in countless industrial and medical appliances. Fluctuations in thermophysical properties of such fluids due to variations in temperature have not received due attention in the available literature. Present investigation aims to fill this void by analyzing the flow of copper-water nanofluid with temperature dependent viscosity past a Riga plate. Strong wall suction and viscous dissipation have also been taken into account. Numerical solutions for the resulting nonlinear system have been obtained. Results are presented in the graphical and tabular format in order to facilitate the physical analysis. An estimated expression for skin friction coefficient and Nusselt number are obtained by performing linear regression on numerical data for embedded parameters. Results indicate that the temperature dependent viscosity alters the velocity, as well as the temperature of the nanofluid and, is of considerable importance in the processes where high accuracy is desired. Addition of copper nanoparticles makes the momentum boundary layer thinner whereas viscosity parameter does not affect the boundary layer thickness. Moreover, the regression expressions indicate that magnitude of rate of change in effective skin friction coefficient and Nusselt number with respect to nanoparticles volume fraction is prominent when compared with the rate of change with variable viscosity parameter and modified Hartmann number.

Keywords: heat transfer, peristaltic flows, radially varying magnetic field, curved channel

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Authors: Oseni Margaret Oladunni, Ogundele Joan Olayinka, Olusanya Olalekan Samuel, Akinniyi Modupe Olakintan

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The world's growing population is pushing humans to look for alternative food sources among underutilised or wild plants. One of these food sources has been identified as Canavalia enisiformis, or jack beans. The only issue with using jack beans is that they contain anti-nutrient chemicals, which must be removed or diminished in order for them to be fit for human consumption. The objective of this study is to determine the nutritional and industrial utility of Canavalia enisiformis by analysing the anti-nutrient, phytochemical, and antioxidant composition of raw whole seed and soaking dehusked seeds using established procedures. Phytate (23.48±0.24, 15.24±0.41 and 14.83±0.00), oxalate (4.32±0.09, 3.96±0.09 and 2.88±0.09), tannins (22.77±0.73, 18.68±0.03 and 17.50±0.46), and lectins (6.67±0.04, 6.20±0.01 and 6.42±0.07) exhibited the highest anti-nutrient values in raw whole seed and, at the very least, in dehusked, soaked seeds. The samples were subjected to phytochemical screening, which detected the presence of cardiac glycosides as well as anthraquinones, alkaloids, tannins, saponins, steroids, flavonoids, terpenoids, phlobatannins, and flavonoids. Due to the reduction in phytochemical contents quantified as a result of dehusking and soaking, phenolbatannins and anthraquinones were not found in the samples. The research findings also demonstrated elevated concentrations of several plausible phytochemical components with potential medical value, with the raw whole seed exhibiting the greatest capacity to scavenge free radicals. Accordingly, the study's findings validate the seed's therapeutic applications and imply that it might be an inexpensive source of antioxidants for humans and animals alike.

Keywords: dehusking, soaking, anti-nutrients, antioxidants, jack bean

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Authors: Ling Ai, Ziyu Zhao, Zeyu Zhou, Xiaochen Yang, Heng Zhai, Stuart Holmes

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Optimizing the catalyst layer structure is crucial for enhancing the performance of proton exchange membrane fuel cells (PEMFCs) with low Platinum (Pt) loading. Current works focused on the utilization, durability, and site activity of Pt particles on support, and performance enhancement has been achieved by loading Pt onto porous support with different morphology, such as graphene, carbon fiber, and carbon black. Some schemes have also incorporated cost considerations to achieve lower Pt loading. However, the design of the catalyst layer (CL) structure in the membrane electrode assembly (MEA) must consider the interactions between the layers. Addressing the crucial aspects of water management, low contact resistance, and the establishment of effective three-phase boundary for MEA, multi-walled carbon nanotubes (MWCNTs) are promising CL support due to their intrinsically high hydrophobicity, high axial electrical conductivity, and potential for ordered alignment. However, the drawbacks of MWCNTs, such as strong agglomeration, wall surface chemical inertness, and unopened ends, are unfavorable for Pt nanoparticle loading, which is detrimental to MEA processing and leads to inhomogeneous CL surfaces. This further deteriorates the utilization of Pt and increases the contact resistance. Robust chemical oxidation or nitrogen doping can introduce polar functional groups onto the surface of MWCNTs, facilitating the creation of open tube ends and inducing defects in tube walls. This improves dispersibility and load capacity but reduces length and conductivity. Consequently, a trade-off exists between maintaining the intrinsic properties and the degree of functionalization of MWCNTs. In this work, MWCNTs were modified based on the operational requirements of the MEA from the viewpoint of interlayer interactions, including the search for the optimal degree of oxidation, N-doping, and micro-arrangement. MWCNT were functionalized by oxidizing, N-doping, as well as micro-alignment to achieve lower contact resistance between CL and proton exchange membrane (PEM), better hydrophobicity, and enhanced performance. Furthermore, this work expects to construct a more continuously distributed three-phase boundary by aligning MWCNT to form a locally ordered structure, which is essential for the efficient utilization of Pt active sites. Different from other chemical oxidation schemes that used HNO3:H2SO4 (1:3) mixed acid to strongly oxidize MWCNT, this scheme adopted pure HNO3 to partially oxidize MWCNT at a lower reflux temperature (80 ℃) and a shorter treatment time (0 to 10 h) to preserve the morphology and intrinsic conductivity of MWCNT. The maximum power density of 979.81 mw cm-2 was achieved by Pt loading on 6h MWCNT oxidation time (Pt-MWCNT6h). This represented a 59.53% improvement over the commercial Pt/C catalyst of 614.17 (mw cm-2). In addition, due to the stronger electrical conductivity, the charge transfer resistance of Pt-MWCNT6h in the electrochemical impedance spectroscopy (EIS) test was 0.09 Ohm cm-2, which was 48.86% lower than that of Pt/C. This study will discuss the developed catalysts and their efficacy in a working fuel cell system. This research will validate the impact of low-functionalization modification of MWCNTs on the performance of PEMFC, which simplifies the preparation challenges of CL and contributing for the widespread commercial application of PEMFCs on a larger scale.

Keywords: carbon nanotubes, electrocatalyst, membrane electrode assembly, proton exchange membrane fuel cell

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