Search results for: hepatic adverse effects
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11097

Search results for: hepatic adverse effects

7227 The Ameliorative Effects of Nanoencapsulated Triterpenoids from Petri-Dish Cultured Antrodia cinnamomea on Reproductive Function of Diabetic Male Rats

Authors: Sabri Sudirman, Yuan-Hua Hsu, Zwe-Ling Kong

Abstract:

Male reproductive dysfunction is predominantly due to insulin resistance and hyperglycemia result in inflammation and oxidative stress. Furthermore, nanotechnology provides an alternative approach to improve the bioavailability of natural active food ingredients. Therefore, the aim of this study were to investigate nanoencapsulated triterpenoids from petri-dish cultured Antrodia cinnamomea (PAC) nanoparticles whether it could increase the bioavailability; in addition, the anti-inflammatory and anti-oxidative effects could more effectively ameliorate the reproductive function of diabetic male rats. First, PAC encapsulated in chitosan-silica nanoparticles (Nano-PAC) were prepared by biosilicification method. Scanning electron micrographs confirm the average particle size is about 30 nm, and the encapsulation efficiency is 83.7% by HPLC. Diabetic male Sprague-Dawley rats were induced by high fat diet (40% kcal from fat) and streptozotocin (35 mg/kg). Nano-PAC was administered by oral gavage in three doses (4, 8 and 20 mg/kg) for 6 weeks. Besides, metformin (300 mg/kg) and nanoparticles (Nano) were treated as the positive and negative control respectively. Results indicated that 4 mg/kg Nano-PAC administration for 6 weeks improved hyperglycemia, insulin resistance, and also reduced advanced glycation end products in plasma. In addition, 8 mg/kg Nano-PAC ameliorated morphological of testicular seminiferous tubules, sperm morphology and motility, reactive oxygen species production and mitochondrial membrane potential. Moreover, 20 mg/kg Nano-PAC restored reproductive endocrine system function and increased KiSS-1 level in plasma. In plasma or testis anti-oxidant superoxide dismutase, glutathione peroxidase and catalase were increased whereas malondialdehyde, as well as pro-inflammatory cytokines tumor necrosis factor-α, interleukin-6, and interferon-gamma, decreased. Most importantly, 8 mg/kg Nano-PAC down-regulated the oxidative stress induced c-Jun N-terminal kinase (JNK) signaling pathway. Our study successfully nanoencapsulated PAC to form nanoparticles and low-dose Nano-PAC improved diabetes-induced hyperglycemia, inflammation and oxidative stress to ameliorate the reproductive function of diabetic male rats.

Keywords: Antrodia cinnamomea, diabetes mellitus, male reproduction, nanoparticles

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7226 The Effect of Rowing Exercise on Elderly Health

Authors: Rachnavy Pornthep, Khaothin Thawichai

Abstract:

The purpose of this paper was to investigate the effects of rowing ergometer exercise on older persons health. The subjects were divided into two groups. Group 1 was control group (10 male and 10 female) Group 2 was experimental group (10 male and 10 female). The time for study was 12 week. Group 1 engage in normal daily activities Group 2 Training with rowing machine for 20 minutes three days a week. The average age of the experimental group was 73.7 years old, mean weight 55.4 kg, height 154.8 cm in the control group, mean age was 74.95 years, mean weight 48.6 kg, mean height 153.85 cm. Physical fitness test composted of body size, flexibility, Strength, muscle endurance and cardiovascular endurance. The comparison between the experimental and control groups before training showed that body weight, body mass index and waist to hip ratio were significantly different. The flexibility, strength, cardiovascular endurance was not significantly different. The comparison between the control group and the experimental group after training showed that body weight, body mass index and cardiovascular endurance were significantly different. The ratio of waist to hips, flexibility and muscular strength were not significantly different. Comparison of physical fitness before training and after training of the control group showed that body weight, flexibility (Sit and reach) and muscular strength (30 – Second chair stand) were significantly different. Body mass index, waist to hip ratio, muscles flexible (Shoulder girdle flexibility), muscle strength (30 – Second arm curl) and the cardiovascular endurance were not significantly difference. Comparison of physical fitness before training and after training the experimental group showed that waist to hip ratio, flexibility (sit and reach) muscle strength (30 – Second chair stand), cardiovascular endurance (Standing leg raises - up to 2 minutes) were significantly different. The Body mass index and the flexibility (Shoulder girdle flexibility) no significantly difference. The study found that exercising with rowing machine can improve the physical fitness of the elderly, especially the cardiovascular endurance, corresponding with the past research on the effects of exercise in the elderly with different exercise such as cycling, treadmill, walking on the elliptical machine. Therefore, we can conclude that exercise by using rowing machine can improve cardiovascular system and flexibility in the elderly.

Keywords: effect, rowing, exercise, elderly

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7225 A Dimensional Approach to Family Involvement in Forensic Mental Health Settings - Prevention of the Systemic Replication of Abuse, Need for Accepted Falsehoods and Family Guilt and Shame

Authors: Katie E. Jennings

Abstract:

The interactions between family dynamics and environmental factors with mental health vulnerability in individuals are well known and are a theme for on-going research and debate. The impact upon mental health issues and forensic issues on family dynamics, experience, and emotional wellbeing cannot be over-Emphasised. For forensic patients with diagnosed mental disorders, these relationships and environments may have also been functionally linked to the development and maintenance of those disorders; with significant adverse childhood experiences being a common feature of many Patient’s histories. Mental health hospitals remove the patient from their home environments and provide treatment outside of these relationships and often outside of the home area. There is, therefore, a major focus on Services ensuring that patients are able to build and maintain relationships with family and friends, requiring services to involve families in Patients' care and treatment wherever possible. There are standards set by Government and clinical bodies that require absolute demonstration of the inclusion of family and friends in all aspects of the care and treatment of forensic patients. For some patients and family members, this push to take on a “role” in care can be unhelpful, extremely stressful, and has constant implications for the potential delicate reparation of relationships. Based on work undertaken for over 20 years in forensic mental health settings, this paper explores the positive psychology approach to a dimensional model to family inclusion in mental health care that learns from family court work and allows for the maintenance of relationships to be at both proximal and Distil levels; to prevent the replication of abuse, decrease the need for falsehoods and assist the recovery of all. The model is based on allowing families to choose to not be involved or be involved in different ways if this is seen to be more helpful. It also allows patients to choose the level of potential involvement that they would find helpful, and for this to be reviewed at a timeframe agreed by all parties, rather than when the next survey is due or the patient has a significant care meeting. This paper is significant as there is a lack of research to support services to use a positive psychology approach to work in this area, the assumption that being asked to be involved must be positive for all seems naïve at best for this patient group. Work relating to the psychology of family can significantly contribute to the development of knowledge in this area. The development of a dimensional model will support choice within families and assist in the development of more honest and open relationships.

Keywords: family dynamics, forensic, mental disorder, positive psychology

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7224 Effects of the Compressive Eocene Tectonic Phase in the Bou Kornine-Ressas-Messella Structure and Surroundings (Northern Tunisia)

Authors: Aymen Arfaoui, Abdelkader Soumaya

Abstract:

The Messalla-Ressas-Bou Kornine (MRB) and Hammamet Korbous (HK) major trending North-South fault zones provide a good opportunity to show the effects of the Eocene compressive phase in northern Tunisia. They acted as paleogeographical boundaries during the Mesozoic and belonged to a significant strike-slip corridor called the «North-South Axis,» extending from the Saharan platform at the South to the Gulf of Tunis at the North. Our study area is situated in a relay zone between two significant strike-slip faults (HK and MRB), separating the Atlas domain from the Pelagian Block. We used a multidisciplinary approach, including fieldwork, stress inversion, and geophysical profiles, to argue the shortening event that affected the study region. The MRB and HK contractional duplex is a privileged area for a local stress field and stress nucleation. The stress inversion of fault slip data reveals an Eocene compression with NW-SE trending SHmax, reactivating most of the ancient Mesozoic normal faults in the region. This shortening phase is represented in the MRB belt by an angular unconformity between the Upper Eocene over various Cretaceous strata. The stress inversion data reveal a compressive tectonic with an average NW-SE trending Shmax. The major N-S faults are reactivated under this shortening as sinistral oblique faults. The orientation of SHmax deviates from NW-SE to E-W near the preexisting deep faults of MRB and HK. This E-W stress direction generated the emerging overlap of Ressas-Messella and blind thrust faults in the Cretaceous deposits. The connection of the sub-meridian reverse faults in depth creates "flower structures" under an E-W local compressive stress. In addition, we detected a reorientation of the SHmax into an N-S direction in the central part of the MRB - HK contractional duplex, creating E-W reverse faults and overlapping zones. Finally, the Eocene compression constituted the first major tectonic phase which inverted the Mesozoic preexisting extensive fault system in Northern Tunisia.

Keywords: Tunisia, eocene compression, tectonic stress field, Bou Kornine-Ressas-Messella

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7223 Assessing Social Sustainability for Biofuels Supply Chains: The Case of Jet Biofuel in Brazil

Authors: Z. Wang, F. Pashaei Kamali, J. A. Posada Duque, P. Osseweijer

Abstract:

Globally, the aviation sector is seeking for sustainable solutions to comply with the pressure to reduce greenhouse gas emissions. Jet fuels derived from biomass are generally perceived as a sustainable alternative compared with their fossil counterparts. However, the establishment of jet biofuels supply chains will have impacts on environment, economy, and society. While existing studies predominantly evaluated environmental impacts and techno-economic feasibility of jet biofuels, very few studies took the social / socioeconomic aspect into consideration. Therefore, this study aims to provide a focused evaluation of social sustainability for aviation biofuels with a supply chain perspective. Three potential jet biofuel supply chains based on different feedstocks, i.e. sugarcane, eucalyptus, and macauba were analyzed in the context of Brazil. The assessment of social sustainability is performed with a process-based approach combined with input-output analysis. Over the supply chains, a set of social sustainability issues including employment, working condition (occupational accident and wage level), labour right, education, equity, social development (GDP and trade balance) and food security were evaluated in a (semi)quantitative manner. The selection of these social issues is based on two criteria: (1) the issues are highly relevant and important to jet biofuel production; (2) methodologies are available for assessing these issues. The results show that the three jet biofuel supply chains lead to a differentiated level of social effects. The sugarcane-based supply chain creates the highest number of jobs whereas the biggest contributor of GDP turns out to be the macauba-based supply chain. In comparison, the eucalyptus-based supply chain stands out regarding working condition. It is also worth noting that biojet fuel supply chain with high level of social benefits could result in high level of social concerns (such as occupational accident, violation of labour right and trade imbalance). Further research is suggested to investigate the possible interactions between different social issues. In addition, the exploration of a wider range of social effects is needed to expand the comprehension of social sustainability for biofuel supply chains.

Keywords: biobased supply chain, jet biofuel, social assessment, social sustainability, socio-economic impacts

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7222 Removal of Vanadium from Industrial Effluents by Natural Ion Exchanger

Authors: Shashikant R. Kuchekar, Haribhau R. Aher, Priti M. Dhage

Abstract:

The removal vanadium from aqueous solution using natural exchanger was investigated. The effects of pH, contact time and exchanger dose were studied at ambient temperature (25 0C ± 2 0C). The equilibrium process was described by the Langmuir isotherm model with adsorption capacity for vanadium. The natural exchanger i.e. tamarindus seeds powder was treated with formaldehyde and sulpuric acid to increase the adsorptivity of metals. The maximum exchange level was attained as 80.1% at pH 3 with exchanger dose 5 g and contact time 60 min. Method is applied for removal of vanadium from industrial effluents.

Keywords: industrial effluent, natural ion exchange, Tamarindous indica, vanadium

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7221 Stability Analysis of SEIR Epidemic Model with Treatment Function

Authors: Sasiporn Rattanasupha, Settapat Chinviriyasit

Abstract:

The treatment function adopts a continuous and differentiable function which can describe the effect of delayed treatment when the number of infected individuals increases and the medical condition is limited. In this paper, the SEIR epidemic model with treatment function is studied to investigate the dynamics of the model due to the effect of treatment. It is assumed that the treatment rate is proportional to the number of infective patients. The stability of the model is analyzed. The model is simulated to illustrate the analytical results and to investigate the effects of treatment on the spread of infection.

Keywords: basic reproduction number, local stability, SEIR epidemic model, treatment function

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7220 Preconcentration and Determination of Lead Ion in Environmental Samples by Poly Urea-Formaldehyde

Authors: Elham Moniri, Parvane Bozorgniya, Hamidreza Shahbazi

Abstract:

In this research, poly urea-formaldehyde was prepared. The poly urea-formaldehyde was characterized by fourier transform infra-red spectroscopy. Then the effects of various parameters on Pb(II) sorption such as pH, contact time were studied. The optimum pH value for sorption of Pb(II) was 5. The sorption capacity of poly urea-formaldehyde for Pb(II) were 40 mg g−1. A Pb(II) removal of 90% was obtained. The profile of Pb(II) uptake on this sorbent reflects good accessibility of the chelating sites in the poly urea-formaldehyde. The developed method was utilized for determination of Pb(II) in environmental water samples by flame atomic absorption spectrometry with satisfactory results.

Keywords: poly urea-formaldehyde, lead Ion, environmental sample, determination

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7219 Predictability of Thermal Response in Housing: A Case Study in Australia, Adelaide

Authors: Mina Rouhollahi, J. Boland

Abstract:

Changes in cities’ heat balance due to rapid urbanization and the urban heat island (UHI) have increased energy demands for space cooling and have resulted in uncomfortable living conditions for urban residents. Climate resilience and comfortable living spaces can be addressed through well-designed urban development. The sustainable housing can be more effective in controlling high levels of urban heat. In Australia, to mitigate the effects of UHIs and summer heat waves, one solution to sustainable housing has been the trend to compact housing design and the construction of energy efficient dwellings. This paper analyses whether current housing configurations and orientations are effective in avoiding increased demands for air conditioning and having an energy efficient residential neighborhood. A significant amount of energy is consumed to ensure thermal comfort in houses. This paper reports on the modelling of heat transfer within the homes using the measurements of radiation, convection and conduction between exterior/interior wall surfaces and outdoor/indoor environment respectively. The simulation was tested on selected 7.5-star energy efficient houses constructed of typical material elements and insulation in Adelaide, Australia. The chosen design dwellings were analyzed in extremely hot weather through one year. The data were obtained via a thermal circuit to accurately model the fundamental heat transfer mechanisms on both boundaries of the house and through the multi-layered wall configurations. The formulation of the Lumped capacitance model was considered in discrete time steps by adopting a non-linear model method. The simulation results focused on the effects of orientation of the solar radiation on the dynamic thermal characteristics of the houses orientations. A high star rating did not necessarily coincide with a decrease in peak demands for cooling. A more effective approach to avoid increasing the demands for air conditioning and energy may be to integrate solar–climatic data to evaluate the performance of energy efficient houses.

Keywords: energy-efficient residential building, heat transfer, neighborhood orientation, solar–climatic data

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7218 Calculation Of Energy Gap Of (Ga,Mn)As Diluted Magnetic Semiconductor From The Eight-Band k.p Model

Authors: Khawlh A. Alzubaidi, Khadijah B. Alziyadi, Amor M. Alsayari

Abstract:

Now a days (Ga, Mn) is one of the most extensively studied and best understood diluted magnetic semiconductors. Also, the study of (Ga, Mn)As is a fervent research area since it allows to explore of a variety of novel functionalities and spintronics concepts that could be implemented in the future. In this work, we will calculate the energy gap of (Ga, Mn)As using the eight-band model. In the Hamiltonian, the effects of spin-orbit, spin-splitting, and strain will be considered. The dependence of the energy gap on Mn content, and the effect of the strain, which is varied continuously from tensile to compressive, will be studied. Finally, analytical expressions for the (Ga, Mn)As energy band gap, taking into account both parameters (Mn concentration and strain), will be provided.

Keywords: energy gap, diluted magnetic semiconductors, k.p method, strain

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7217 Short-Term Effects of Seed Dressing With Azorhizobium Caulinodans on Establishment, Development and Yield of Early Maturing Maize ( Zea Mays L.) In Zimbabwe

Authors: Gabriel Vusanimuzi Nkomo

Abstract:

The majority of soils in communal areas of Zimbabwe are sandy and inherently infertile and sustainable cultivation is not feasible without addition of plant nutrients. Most farmers find it difficult to raise the capital required for investments in mineral fertilizer and find it cheaper to use low nutrition animal manure. An experiment was conducted to determine the effects of nitrokara biofertiliser on early growth, development and maize yield while also comparing nitrokara biofertiliser on availability of nitrogen and phosphorous in soil. The experiment was conducted at Africa University Farm. The experiment had six treatments (nitrokara +300kg/ha Compound D, nitrokara+ 300kg/ha Compound D(7N;14P;7K) + 75kg/ha Ammonium Nitrate(AN), nitrokara +300kg/ha Compound D +150kg AN, nitrokara +300kg/ha Compound D +225kg/ha AN, nitrokara +300kg/ha Compound D + 300 kg/ha AN and 0 nitrokara+300kg/ha Compound D +0 AN). Early maturing SC 403 maize (Zea mays) was inoculated with nitrokara and a compound mineral fertilizer at 300 kg/ha at planting while ammonium nitrate was applied at 45 days after planting. There were no significant differences (P > 0.05) on emergence % from 5days up to 10 days after planting using maize seed inoculated with nitrokara. Emergence percentage varied with the number of days. At 5 days the emergence % was 62% to a high of 97 % at 10 days after emergence among treatments. There were no significant differences (P > 0.05) on plant biomass on treatments 1 to 6 at 4 weeks after planting as well as at 8 weeks after planting. There were no significant differences among the treatments on the availability of nitrogen after 6 weeks (P > 0.05). However at 8 and 10 weeks after planting there were significant differences among treatments on nitrogen availability (P < 0.05). There were no significant differences among the treatments at week 6 after planting on soil pH (p > 0.05). However there were significant differences among treatments pH at weeks 9 and 12 (p < 0.05). There were significant differences among treatments on phosphorous availability at 6, 8 and 10 weeks after planting (p < 0.05). There were no significant differences among treatments on stem diameter at 3 and 6 weeks after planting (p > 0.05).However at 9 and 12 weeks after planting there were significant differences among treatments on stem diameter (p < 0.05).There were no significant differences among treatments on plant height from week 3 up to week 6 on plant height (P > 0.05).However there were significant differences among treatments at week 9 and 12 (p < 0.05). There were significant differences among treatments on days to early, 50% and 100% anthesis (P < 0.05). There were significant differences during early, 50% and 100% days to silking among the treatments (P < 0.05).Also there were significant differences during early, 50% and 100% days to silking among the treatments (P < 0.05).The study revealed that inoculation of nitrokara biofertiliser at planting with subsequent addition of ammonium nitrate has a positive effect on maize crop development and yield.

Keywords: nitrokara, biofertiliser, symbiotic, plant biomass, inoculated

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7216 Nozzle-to-Surface Distances Effect on Heat Transfer of Two-Phase Impinging Jets

Authors: Aspen W. Glaspell, Victoria J. Rouse, Brian K. Friedrich, Kyosung Choo

Abstract:

Heat transfer of two-phase impinging jet on a flat plate surface are experimentally investigated. The effects of the nozzle-to-surface distance and volumetric quality on the Nusselt number are considered. The results show that the normalized stagnation Nusselt number drastically increase with decreasing the nozzle-to-surface distance due to the jet deflection effect. Based on the experimental results, new correlations for the stagnation Nusselt number are developed as a function of the nozzle-to-surface distance.

Keywords: jet impingement, water jet, air assisted, circular jet

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7215 An Interpretative Historical Analysis of Asylum and Refugee Policies and Attitudes to Australian Immigration Laws

Authors: Kamal Kithsiri Karunadasa Hewawasam Revulge

Abstract:

This paper is an interpretative historical analysis of Australian migration laws that examines asylum and refugee policies and attitudes in Australia. It looks at major turning points in Australian migration history, and in doing so, the researcher reviewed relevant literature on the aspects crucial to highlighting the current trend of Australian migration policies. The data was collected using secondary data from official government sources, including annual reports, media releases on immigration, inquiry reports, statistical information, and other available literature to identify critical historical events that significantly affected the systematic developments of asylum seekers and refugee policies in Australia and to look at the historical trends of official thinking. A reliance on using these official sources is justified as those are the most convincing sources to analyse the historical events in Australia. Additional literature provides us with critical analyses of the behaviour and culture of the Australian immigration administration. The analytical framework reviewed key Australian Government immigration policies since British colonization and the settlement era of 1787–the 1850s and to the present. The fundamental basis for doing so is that past events and incidents offer us clues and lessons relevant to the present day. Therefore, providing a perspective on migration history in Australia helps analyse how current policymakers' strategies developed and changed over time. Attention is also explicitly focused on Australian asylum and refugee policy internationally, as it helped to broaden the analysis. The finding proved a link between past events and adverse current Australian government policies towards asylum seekers and refugees. It highlighted that Australia's current migration policies are part of a carefully and deliberately planned pattern that arose from the occupation of Australia by early British settlers. In this context, the remarkable point is that the historical events of taking away children from their Australian indigenous parents, widely known as the 'stolen generation' reflected a model of assimilation, or a desire to absorb other cultures into Australian society by fully adopting the settlers' language, their culture, and losing indigenous people's traditions. Current Australian policies towards migrants reflect the same attitude. Hence, it could be argued that policies and attitudes towards asylum seekers and refugees, particularly so-called 'boat people' to some extent, still reflect Australia's earlier colonial and 'white Australia' history.

Keywords: migration law, refugee law, international law, administrative law

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7214 Synthesis and Characterisation of Bi-Substituted Magnetite Nanoparticles by Mechanochemical Processing (MCP)

Authors: Morteza Mohri Esfahani, Amir S. H. Rozatian, Morteza Mozaffari

Abstract:

Single phase magnetite nanoparticles and Bi-substituted ones were prepared by mechanochemical processing (MCP). The effects of Bi-substitution on the structural and magnetic properties of the nanoparticles were studied by X-ray Diffraction (XRD) and magnetometry techniques, respectively. The XRD results showed that all samples have spinel phase and by increasing Bi content, the main diffraction peaks were shifted to higher angles, which means the lattice parameter decreases from 0.843 to 0.838 nm and then increases to 0.841 nm. Also, the results revealed that increasing Bi content lead to a decrease in saturation magnetization (Ms) from 74.9 to 48.8 emu/g and an increase in coercivity (Hc) from 96.8 to 137.1 Oe.

Keywords: bi-substituted magnetite nanoparticles, mechanochemical processing, X-ray diffraction, magnetism

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7213 Effect of Preoperative Single Dose Dexamethasone and Lignocaine on Post-Operative Quality of Recovery and Pain Relief after Laparoscopic Cholecystectomy

Authors: Gurjeet Khurana, Surender Singh, Poonam Arora, Praveendra K. Sachan

Abstract:

Introduction: Post-operative quality of recovery is the key outcome in the perspective of anesthesiologist. It is directly related to patient satisfaction. This is unsurprising, considering most aspects of a poor quality recovery after surgery will impair satisfaction with care. This study was thus undertaken to evaluate effects of Dexamethasone and Lignocaine on Quality of Recovery using QoR- 40 questionnaire and compare their effects. Material and methods: After obtaining the ethical committee approval and written informed consent, 67 patients of 18-60 years, ASA grade I and II scheduled for elective laparoscopic cholecystectomy were randomly allocated into two groups. Group I of 34 patients received 2mg/kg lignocaine diluted to 10ml with normal saline. Group 2 of 33 patients received 0.1 mg/kg I/V Dexamethasone diluted to 10ml with normal saline. QoR-40 was assessed on pre-operative day, and again QoR-40 was assessed at 24 hr post-operative day-1. Postoperative pain scores, nausea and vomiting and shoulder pain were secondary outcomes. Results: The Global QoR-40 was more than 180 at 24 hr in both the groups. The Dexamethasone group had higher Global QoR-40 than lignocaine group 187.94 v/s 182.85. Amongst dimensions of QoR-40 Dexamethasone had statistically better physical comfort, physical independence, and pain relief as compared to Lignocaine. Positive items had excellent responses in Dexamethasone group. Headache, backache and sore throat were also less severe in Dexamethasone group as compared to Lignocaine group. Dexamethasone group had lower VAS compared to lignocaine group. Similarly, there was less fentanyl consumption in dexamethasone group (364.08 ± 127.31) in postoperative period when compared to the lignocaine group (412.31 ± 147.8). Group receiving dexamethasone had 36% increase in appetite compared to lignocaine group (17.6%), which facilitated early oral feeding. Frequency of PONV was less in group-2 at different time interval as compared to group 1. Total episode of PONV were 18 in group 1 and 7 in group 2. Statistically significant difference was seen among two groups (p value= 0.007). Use of antiemetic was more in group 1 as compared to group 2 at all the times, though it was not statistically significant at different time intervals. Antiemetics were administered to 18 patients in group 1 as compared to 5 patients in group 2 postoperatively. Statistically significant difference (p value= 0.011) was seen in total antiemetic consumption. Conclusion: Our study demonstrated that pre-operative administration of a single dose of dexamethasone enhanced the quality of recovery after laparoscopic cholecystectomy as compared to Lignocaine bolus dose.

Keywords: dexamethasone, lignocaine, QoR-40 questionnaire, quality of recovery

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7212 Impact of Ocean Acidification on Gene Expression Dynamics during Development of the Sea Urchin Species Heliocidaris erythrogramma

Authors: Hannah R. Devens, Phillip L. Davidson, Dione Deaker, Kathryn E. Smith, Gregory A. Wray, Maria Byrne

Abstract:

Marine invertebrate species with calcifying larvae are especially vulnerable to ocean acidification (OA) caused by rising atmospheric CO₂ levels. Acidic conditions can delay development, suppress metabolism, and decrease the availability of carbonate ions in the ocean environment for skeletogenesis. These stresses often result in increased larval mortality, which may lead to significant ecological consequences including alterations to the larval settlement, population distribution, and genetic connectivity. Importantly, many of these physiological and developmental effects are caused by genetic and molecular level changes. Although many studies have examined the effect of near-future oceanic pH levels on gene expression in marine invertebrates, little is known about the impact of OA on gene expression in a developmental context. Here, we performed mRNA-sequencing to investigate the impact of environmental acidity on gene expression across three developmental stages in the sea urchin Heliocidaris erythrogramma. We collected RNA from gastrula, early larva, and 1-day post-metamorphic juvenile sea urchins cultured at present-day and predicted future oceanic pH levels (pH 8.1 and 7.7, respectively). We assembled an annotated reference transcriptome encompassing development from egg to ten days post-metamorphosis by combining these data with datasets from two previous developmental transcriptomic studies of H. erythrogramma. Differential gene expression and time course analyses between pH conditions revealed significant alterations to developmental transcription that are potentially associated with pH stress. Consistent with previous investigations, genes involved in biomineralization and ion transport were significantly upregulated under acidic conditions. Differences in gene expression between the two pH conditions became more pronounced post-metamorphosis, suggesting a development-dependent effect of OA on gene expression. Furthermore, many differences in gene expression later in development appeared to be a result of broad downregulation at pH 7.7: of 539 genes differentially expressed at the juvenile stage, 519 of these were lower in the acidic condition. Time course comparisons between pH 8.1 and 7.7 samples also demonstrated over 500 genes were more lowly expressed in pH 7.7 samples throughout development. Of the genes exhibiting stage-dependent expression level changes, over 15% of these diverged from the expected temporal pattern of expression in the acidic condition. Through these analyses, we identify novel candidate genes involved in development, metabolism, and transcriptional regulation that are possibly affected by pH stress. Our results demonstrate that pH stress significantly alters gene expression dynamics throughout development. A large number of genes differentially expressed between pH conditions in juveniles relative to earlier stages may be attributed to the effects of acidity on transcriptional regulation, as a greater proportion of mRNA at this later stage has been nascent transcribed rather than maternally loaded. Also, the overall downregulation of many genes in the acidic condition suggests that OA-induced developmental delay manifests as suppressed mRNA expression, possibly from lower transcription rates or increased mRNA degradation in the acidic environment. Further studies will be necessary to determine in greater detail the extent of OA effects on early developing marine invertebrates.

Keywords: development, gene expression, ocean acidification, RNA-sequencing, sea urchins

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7211 Effects of Covid-19 pandemic in Japan on Japanese People’s and Expatriates’ Lifestyles

Authors: Noriyuki Suyama

Abstract:

This paper looked into consumer behavioral changes by analyzing the data collected by ASMARKS Co., one of a research companies in Japan. The purpose of the paper is to understand the two differences of before vs. after COVID-19 pandemic and Japanese living in Japan. Subsequently, examining the analysis results helped obtain useful insights into new business models for business parties in Japan as a microlevel perspective. The paper also tried to explore future conditions of globalization by taking into consideration nation’s political and economic changes as a macro-level perspective. The COVID-19 has been continuing its spread across the world with more than 60 million confirmed cases in 190 countries. This pandemic with restricted scopes of behavior mandates have disrupted the consumer habits of their lifestyles. Consumers have tendency to learn new ways when they have trouble in taking routine action. For example, the government forces people to refrain from going out, they try to telecommute at home. If the situation come back to normal, people still change their lifestyles to fit in the best. Some of data show typical effects of COVID-19; forceful exposure to digitalized work-life styles; more flexible time at home; importance of trustful and useful information gathering between what's good and bad;etc. in comparison with before vs. after COVID-19 pandemic. In addition, Japanese have less changed their lifestyles than Expatriates living in Japan. For example, while 94% of the expatriates have decreased their outgo because of self-quarantine, only 55% of the Japanese have done. There are more differences in both comparisons in the analysis results. The economic downtrend resulting from COVID-19 is supposed to be at least as devastating if not more so than that of the financial crisis. With unemployment levels in the US taking two weeks to reach what took 6 months in the 2008 crisis, there is no doubt of a global recession some predict could reach 10% or above of GDP. As a result, globalization in the global supply chain of goods and services will end up with negative impact. A lot of governmental financial and economic policies are supposed to focus on their own profits and interests, exclusing other countries interests as is the case with the Recovery Act just after the global financial crisis from 2007 to 2008. Both micro- and macro-levels analysis successfully reveal important connotations and managerial implications of business in Japan for Japanese consumers as well as after COVID-19 global business.

Keywords: COVID-19, lifestyle in Japan, expatriates, consumer behavior

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7210 Implicit Bias as One Obstacle to Gender Equity

Authors: Kellina Craig-Henderson

Abstract:

Today, there is increased attention to the role of social perceptions in the selection, hiring, and management of employees and the evaluation and promotion of students. In some contexts, where women or members of certain social groups have been historically underrepresented there is evidence that these perceptions reflect the implicit biases people harbor. Research in the social and psychological sciences reveals that implicit biases against women unfairly disadvantage them in academic and work settings. This presentation will provide an overview of the current state of knowledge on an implicit bias as well as the problems associated with it. How employers, educators and other evaluators can inoculate themselves from the pernicious effects of these biases will be considered.

Keywords: gender equity, implicit bias, social psychology, unconscious bias

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7209 Utilizing Artificial Intelligence to Predict Post Operative Atrial Fibrillation in Non-Cardiac Transplant

Authors: Alexander Heckman, Rohan Goswami, Zachi Attia, Paul Friedman, Peter Noseworthy, Demilade Adedinsewo, Pablo Moreno-Franco, Rickey Carter, Tathagat Narula

Abstract:

Background: Postoperative atrial fibrillation (POAF) is associated with adverse health consequences, higher costs, and longer hospital stays. Utilizing existing predictive models that rely on clinical variables and circulating biomarkers, multiple societies have published recommendations on the treatment and prevention of POAF. Although reasonably practical, there is room for improvement and automation to help individualize treatment strategies and reduce associated complications. Methods and Results: In this retrospective cohort study of solid organ transplant recipients, we evaluated the diagnostic utility of a previously developed AI-based ECG prediction for silent AF on the development of POAF within 30 days of transplant. A total of 2261 non-cardiac transplant patients without a preexisting diagnosis of AF were found to have a 5.8% (133/2261) incidence of POAF. While there were no apparent sex differences in POAF incidence (5.8% males vs. 6.0% females, p=.80), there were differences by race and ethnicity (p<0.001 and 0.035, respectively). The incidence in white transplanted patients was 7.2% (117/1628), whereas the incidence in black patients was 1.4% (6/430). Lung transplant recipients had the highest incidence of postoperative AF (17.4%, 37/213), followed by liver (5.6%, 56/1002) and kidney (3.6%, 32/895) recipients. The AUROC in the sample was 0.62 (95% CI: 0.58-0.67). The relatively low discrimination may result from undiagnosed AF in the sample. In particular, 1,177 patients had at least 1 AI-ECG screen for AF pre-transplant above .10, a value slightly higher than the published threshold of 0.08. The incidence of POAF in the 1104 patients without an elevated prediction pre-transplant was lower (3.7% vs. 8.0%; p<0.001). While this supported the hypothesis that potentially undiagnosed AF may have contributed to the diagnosis of POAF, the utility of the existing AI-ECG screening algorithm remained modest. When the prediction for POAF was made using the first postoperative ECG in the sample without an elevated screen pre-transplant (n=1084 on account of n=20 missing postoperative ECG), the AUROC was 0.66 (95% CI: 0.57-0.75). While this discrimination is relatively low, at a threshold of 0.08, the AI-ECG algorithm had a 98% (95% CI: 97 – 99%) negative predictive value at a sensitivity of 66% (95% CI: 49-80%). Conclusions: This study's principal finding is that the incidence of POAF is rare, and a considerable fraction of the POAF cases may be latent and undiagnosed. The high negative predictive value of AI-ECG screening suggests utility for prioritizing monitoring and evaluation on transplant patients with a positive AI-ECG screening. Further development and refinement of a post-transplant-specific algorithm may be warranted further to enhance the diagnostic yield of the ECG-based screening.

Keywords: artificial intelligence, atrial fibrillation, cardiology, transplant, medicine, ECG, machine learning

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7208 Examining the Relationship Between Job Stress And Burnout Among Academic Staff During The Covid-19 Pandemic; The Importance Of Emotional Intelligence

Authors: Parisa Gharibi Khoshkar

Abstract:

The global outbreak of Covid-19 forced a swift shift in the education sector, transitioning from traditional in-person settings to remote online setups in a short period. This abrupt change, coupled with health risks and other stressors such as the lack of social interaction, has had a negative impact on academic staff, leading to increased job-related stress and psychological pressures that can result in burnout. To address this, the current research aims to investigate the relationship between job stress and burnout among academic staff in Hebron, Palestine. Furthermore, this study examines the moderating role of emotional intelligence to gain a deeper understanding of its effects in reducing burnout among academic staff and teachers. This research posits that emotional intelligence plays a vital role in helping individuals manage job-related stress and anxiety, thereby preventing burnout. Using a self-administered questionnaire, the study gathered data from 185 samples comprising teachers and administrative staff from two universities in Hebron. The data was analyzed using moderated regression analysis, ANOVA model, and interaction plots. The findings indicate that work-related stress has a direct and significant influence on burnout. Moreover, the current results highlight that emotional intelligence serves as a key determinant in managing the negative effects of the pandemic-induced stress that can lead to burnout among individuals. Given the high-demand nature of the education sector, this research strongly recommends that school authorities take proactive measures to provide much-needed support to academic staff, enabling them to better cope with job stress and fostering an environment that prioritizes individuals' wellbeing. The results of this study hold practical implications for both scholars and practitioners, as they highlight the importance of emotional intelligence in managing stress and anxiety effectively. Understanding the significance of emotional intelligence can aid in implementing targeted interventions and support systems to promote the well-being and resilience of academic staff amidst challenging circumstances.

Keywords: job stress, burnout, employee wellbeing, emotional intelligence, industrial organizational psychology, human resource management, organizational psychology

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7207 Skin-Dose Mapping for Patients Undergoing Interventional Radiology Procedures: Clinical Experimentations versus a Mathematical Model

Authors: Aya Al Masri, Stefaan Carpentier, Fabrice Leroy, Thibault Julien, Safoin Aktaou, Malorie Martin, Fouad Maaloul

Abstract:

Introduction: During an 'Interventional Radiology (IR)' procedure, the patient's skin-dose may become very high for a burn, necrosis and ulceration to appear. In order to prevent these deterministic effects, an accurate calculation of the patient skin-dose mapping is essential. For most machines, the 'Dose Area Product (DAP)' and fluoroscopy time are the only information available for the operator. These two parameters are a very poor indicator of the peak skin dose. We developed a mathematical model that reconstructs the magnitude (delivered dose), shape, and localization of each irradiation field on the patient skin. In case of critical dose exceeding, the system generates warning alerts. We present the results of its comparison with clinical studies. Materials and methods: Two series of comparison of the skin-dose mapping of our mathematical model with clinical studies were performed: 1. At a first time, clinical tests were performed on patient phantoms. Gafchromic films were placed on the table of the IR machine under of PMMA plates (thickness = 20 cm) that simulate the patient. After irradiation, the film darkening is proportional to the radiation dose received by the patient's back and reflects the shape of the X-ray field. After film scanning and analysis, the exact dose value can be obtained at each point of the mapping. Four experimentation were performed, constituting a total of 34 acquisition incidences including all possible exposure configurations. 2. At a second time, clinical trials were launched on real patients during real 'Chronic Total Occlusion (CTO)' procedures for a total of 80 cases. Gafchromic films were placed at the back of patients. We performed comparisons on the dose values, as well as the distribution, and the shape of irradiation fields between the skin dose mapping of our mathematical model and Gafchromic films. Results: The comparison between the dose values shows a difference less than 15%. Moreover, our model shows a very good geometric accuracy: all fields have the same shape, size and location (uncertainty < 5%). Conclusion: This study shows that our model is a reliable tool to warn physicians when a high radiation dose is reached. Thus, deterministic effects can be avoided.

Keywords: clinical experimentation, interventional radiology, mathematical model, patient's skin-dose mapping.

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7206 Destigmatising Generalised Anxiety Disorder: The Differential Effects of Causal Explanations on Stigma

Authors: John McDowall, Lucy Lightfoot

Abstract:

Stigma constitutes a significant barrier to the recovery and social integration of individuals affected by mental illness. Although there is some debate in the literature regarding the definition and utility of stigma as a concept, it is widely accepted that it comprises three components: stereotypical beliefs, prejudicial reactions, and discrimination. Stereotypical beliefs describe the cognitive knowledge-based component of stigma, referring to beliefs (often negative) about members of a group that is based on cultural and societal norms (e.g. ‘People with anxiety are just weak’). Prejudice refers to the affective/evaluative component of stigma and describes the endorsement of negative stereotypes and the resulting negative emotional reactions (e.g. ‘People with anxiety are just weak, and they frustrate me’). Discrimination refers to the behavioural component of stigma, which is arguably the most problematic, as it exerts a direct effect on the stigmatized person and may lead people to behave in a hostile or avoidant way towards them (i.e. refusal to hire them). Research exploring anti-stigma initiatives focus primarily on an educational approach, with the view that accurate information will replace misconceptions and decrease stigma. Many approaches take a biogenetic stance, emphasising brain and biochemical deficits - the idea being that ‘mental illness is an illness like any other.' While this approach tends to effectively reduce blame, it has also demonstrated negative effects such as increasing prognostic pessimism, the desire for social distance and perceptions of stereotypes. In the present study 144 participants were split into three groups and read one of three vignettes presenting causal explanations for Generalised Anxiety Disorder (GAD): One explanation emphasized biogenetic factors as being important in the etiology of GAD, another emphasised psychosocial factors (e.g. aversive life events, poverty, etc.), and a third stressed the adaptive features of the disorder from an evolutionary viewpoint. A variety of measures tapping the various components of stigma were administered following the vignettes. No difference in stigma measures as a function of causal explanation was found. People who had contact with mental illness in the past were significantly less stigmatising across a wide range of measures, but this did not interact with the type of causal explanation.

Keywords: generalised anxiety disorder, discrimination, prejudice, stigma

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7205 Investigating the Effects of Cylinder Disablement on Diesel Engine Fuel Economy and Exhaust Temperature Management

Authors: Hasan Ustun Basaran

Abstract:

Diesel engines are widely used in transportation sector due to their high thermal efficiency. However, they also release high rates of NOₓ and PM (particulate matter) emissions into the environment which have hazardous effects on human health. Therefore, environmental protection agencies have issued strict emission regulations on automotive diesel engines. Recently, these regulations are even increasingly strengthened. Engine producers search novel on-engine methods such as advanced combustion techniques, utilization of renewable fuels, exhaust gas recirculation, advanced fuel injection methods or use exhaust after-treatment (EAT) systems in order to reduce emission rates on diesel engines. Although those aforementioned on-engine methods are effective to curb emission rates, they result in inefficiency or cannot decrease emission rates satisfactorily at all operating conditions. Therefore, engine manufacturers apply both on-engine techniques and EAT systems to meet the stringent emission norms. EAT systems are highly effective to diminish emission rates, however, they perform inefficiently at low loads due to low exhaust gas temperatures (below 250°C). Therefore, the objective of this study is to demonstrate that engine-out temperatures can be elevated above 250°C at low-loaded cases via cylinder disablement. The engine studied and modeled via Lotus Engine Simulation (LES) software is a six-cylinder turbocharged and intercooled diesel engine. Exhaust temperatures and mass flow rates are predicted at 1200 rpm engine speed and several low loaded conditions using LES program. It is seen that cylinder deactivation results in a considerable exhaust temperature rise (up to 100°C) at low loads which ensures effective EAT management. The method also improves fuel efficiency through reduced total pumping loss. Decreased total air induction due to inactive cylinders is thought to be responsible for improved engine pumping loss. The technique reduces exhaust gas flow rate as air flow is cut off on disabled cylinders. Still, heat transfer rates to the after-treatment catalyst bed do not decrease that much since exhaust temperatures are increased sufficiently. Simulation results are promising; however, further experimental studies are needed to identify the true potential of the method on fuel consumption and EAT improvement.

Keywords: cylinder disablement, diesel engines, exhaust after-treatment, exhaust temperature, fuel efficiency

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7204 Simultaneous Electrochemical Detection of Chromium(III), Arsenic(III), and Mercury (II) In Water Using Anodic Stripping Voltammetry

Authors: V. Sai Geethika, Sai Snehitha Yadavalli, Swati Ghosh Acharyya

Abstract:

This study involves a single element and simultaneous electrochemical detection of heavy metal ions through square wave anodic stripping voltammetry. A glassy carbon electrode was used to detect and quantify heavy metals such as As(III), Hg(II), Cr(VI) ions in water. Under optimized conditions, peak separation was obtained by varying concentrations, scan rates, and temperatures. As (III), Hg (II), Cr (III) were simultaneously detected with GCE. Several analytical methods, such as inductively coupled plasma mass spectroscopy (ICP-MS), atomic absorption spectroscopy (AAS), were used previously to detect heavy metal ions, which are authentic but are not good enough for online monitoring due to the bulkiness of the equipment. The study provides a good alternative that is simple, more efficient, and low-cost, involving a portable potentiostat. Heavy metals having different oxidation states can be detected by anodic stripping voltammetry. This method can be easily integrated with electronics. Square wave Anodic stripping voltammetry is used with a potential range of -2.5 V – 2.5 V for single ion detection by a three-electrode cell consisting of silver/silver chloride(Ag/AgCl) as reference and platinum (Pt) counter and glassy carbon (GCE) working electrodes. All three ions are optimized by varying the parameters like concentration, scan rate, pH, temperature, and all these optimized parameters were used for studying the effects of simultaneous detection. The procedure involves preparing an electrolyte using deionized water, cleaning the surface of GCE, depositing the ions by applying the redox potentials obtained from cyclic voltammetry (CV), and then detecting by applying oxidizing potential, i.e., stripping voltage. So this includes ASV techniques such as open-circuit voltage (OCV), chronoamperometry (CA), and square wave voltammetry (SWV). Firstly, the concentration of the ions varied from 50 ppb to 5000 ppb, and an optimum concentration was determined where the three ions were detected. A concentration of 400 ppb was used while varying the temperatures in the range of 25°C – 45°C. Optimum peak intensity was obtained at a temperature of 30°C with a low scan rate of 0.005 V-s⁻¹. All the parameters were optimized, and several effects have been noticed while three ions As(II), Cr(III), Hg(II) were detected alone and simultaneously.

Keywords: Arsenic(III), Chromium(III), glassy carbon electrode, Mercury (II), square wave anodic stripping voltammetry

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7203 Energy Budget Equation of Superfluid HVBK Model: LES Simulation

Authors: M. Bakhtaoui, L. Merahi

Abstract:

The reliability of the filtered HVBK model is now investigated via some large eddy simulations of freely decaying isotropic superfluid turbulence. For homogeneous turbulence at very high Reynolds numbers, comparison of the terms in the spectral kinetic energy budget equation indicates, in the energy-containing range, that the production and energy transfer effects become significant except for dissipation. In the inertial range, where the two fluids are perfectly locked, the mutual friction maybe neglected with respect to other terms. Also the LES results for the other terms of the energy balance are presented.

Keywords: superfluid turbulence, HVBK, energy budget, Large Eddy Simulation

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7202 Burnishing Effect on the Mechanical Characteristics of 100C6

Authors: Ouahiba Taamallah, Tarek Litim

Abstract:

This work relates to the physico-geometrical aspect of the surface layers of 100C6 steel having undergone the burnishing treatment by hard steel ball. The application of tip diamond burnishing promotes better roughness compared to turning. In addition, it allows the surface layers to be consolidated by work hardening phenomena. The optimal effects are closely related to the parameters of the treatment and the active part of the device. With an 80% improvement in roughness resulting from the treatment, burnishing can be defined as a finishing operation within the machining range. With a 40% gain in consolidation rate, this treatment is an efficient process for material consolidation.

Keywords: 100C6 steel, burnishing, hardening, roughness

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7201 Fractional-Order Modeling of GaN High Electron Mobility Transistors for Switching Applications

Authors: Anwar H. Jarndal, Ahmed S. Elwakil

Abstract:

In this paper, a fraction-order model for pad parasitic effect of GaN HEMT on Si substrate is developed and validated. Open de-embedding structure is used to characterize and de-embed substrate loading parasitic effects. Unbiased device measurements are implemented to extract parasitic inductances and resistances. The model shows very good simulation for S-parameter measurements under different bias conditions. It has been found that this approach can improve the simulation of intrinsic part of the transistor, which is very important for small- and large-signal modeling process.

Keywords: fractional-order modeling, GaNHEMT, si-substrate, open de-embedding structure

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7200 Factors Influencing Milk Yield, Quality, and Revenue of Dairy Farms in Southern Vietnam

Authors: Ngoc-Hieu Vu

Abstract:

Dairy production in Vietnam is a relatively new agricultural activity and milk production increased remarkably in recent years. Smallholders are still the main drivers for this development, especially in the southern part of the country. However, information on the farming practices is very limited. Therefore, this study aimed to determine factors influencing milk yield and quality (milk fat, total solids, solids-not-fat, total number of bacteria, and somatic cell count) and revenue of dairy farms in Southern Vietnam. The collection of data was at the farm level; individual animal records were unavailable. The 539 studied farms were located in the provinces Lam Dong (N=111 farms), Binh Duong (N=69 farms), Long An (N=174 farms), and Ho Chi Minh city (N=185 farms). The dataset included 9221 monthly test-day records of the farms from January 2013 to May 2015. Seasons were defined as rainy and dry. Farms sizes were classified as small (< 10 milking cows), medium (10 to 19 milking cows) and large (≥ 20 milking cows). The model for each trait contained year-season and farm region-farm size as subclass fixed effects, and individual farm and residual as random effects. Results showed that year-season, region, and farm size were determining sources of variation affecting all studied traits. Milk yield was higher in dry than in rainy seasons (P < 0.05), while it tended to increase from years 2013 to 2015. Large farms had higher yields (445.6 kg/cow) than small (396.7 kg/cow) and medium (428.0 kg/cow) farms (P < 0.05). Small farms, in contrast, were superior to large farms in terms of milk fat, total solids, solids-not-fat, total number of bacteria, and somatic cell count than large farms (P < 0.05). Revenue per cow was higher in large compared with medium and small farms. In conclusion, large farms achieved higher milk yields and revenues per cow, while small farms were superior in milk quality. Overall, milk yields were low and better training, financial support and marketing opportunities for farmers are needed to improve dairy production and increase farm revenues in Southern Vietnam.

Keywords: farm size, milk yield and quality, season, Southern Vietnam

Procedia PDF Downloads 337
7199 Solar Cell Degradation by Electron Irradiation Effect of Irradiation Fluence

Authors: H. Mazouz, A. Belghachi, F. Hadjaj

Abstract:

Solar cells used in orbit are exposed to radiation environment mainly protons and high energy electrons. These particles degrade the output parameters of the solar cell. The aim of this work is to characterize the effects of electron irradiation fluence on the J (V) characteristic and output parameters of gaAs solar cell by numerical simulation. The results obtained demonstrate that the electron irradiation-induced degradation of performances of the cells concerns mainly the short circuit current.

Keywords: gaAs solar cell, MeV electron irradiation, irradiation fluence, short circuit

Procedia PDF Downloads 442
7198 Calcitriol Improves Plasma Lipoprotein Profile by Decreasing Plasma Total Cholesterol and Triglyceride in Hypercholesterolemic Golden Syrian Hamsters

Authors: Xiaobo Wang, Zhen-Yu Chen

Abstract:

Higher plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) are independent risk factors of cardiovascular disease while high-density lipoprotein cholesterol (HDL-C) is protective. Vitamin D is well-known for its regulatory role in calcium homeostasis. Its potential important role in cardiovascular disease has recently attracted much attention. This study was conducted to investigate effects of different dosage of calcitriol on plasma lipoprotein profile and the underlying mechanism. Sixty male Syrian Golden hamsters were randomly divided into 6 groups: no-cholesterol control (NCD), high-cholesterol control (HCD), groups with calcitriol supplementation at 10/20/40/80ng/kg body weight (CA, CB, CC, CD), respectively. Calcitriol in medium-chain triacylglycerol (MCT) oil was delivered to four experimental groups via oral gavage every other day, while NCD and HCD received MCT oil in the equivalent amount. NCD hamsters were fed with non-cholesterol diet while other five groups were maintained on diet containing 0.2% cholesterol to induce a hypercholesterolemic condition. The treatment lasts for 6 weeks followed by sample collection after hamsters sacrificed. Four experimental groups experienced a reduction in average food intake around 11% compared to HCD with slight decrease in body weight (not exceeding 10%). This reduction reflects on the deceased relative weights of testis, epididymal and perirenal adipose tissue in a dose-dependent manner. Plasma calcitriol levels were measured and was corresponding to oral gavage. At the end of week 6, lipoprotein profiles were improved with calcitriol supplementation with TC, non-HDL-C and plasma triglyceride (TG) decreased in a dose-dependent manner (TC: r=0.373, p=0.009, non-HDL-C: r=0.479, p=0.001, TG: r=0.405, p=0.004). Since HDL-C of four experiment groups showed no significant difference compared to HCD, the ratio of nHDL-C to HDL-C and HDL-C to TC had been restored in a dose-dependent manner. For hamsters receiving the highest level of calcitriol (80ng/kg) showed a reduction of TC by 11.5%, nHDL-C by 24.1% and TG by 31.25%. Little difference was found among six groups on the acetylcholine-induced endothelium-dependent relaxation or contraction of thoracic aorta. To summarize, calcitriol supplementation in hamster at maximum 80ng/kg body weight for 6 weeks lead to an overall improvement in plasma lipoprotein profile with decreased TC and TG level. The molecular mechanism of its effects is under investigation.

Keywords: cholesterol, vitamin D, calcitriol, hamster

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