Search results for: James Alberto Ortega Morales

Authors: James Jin, Weisi Xia, Runzhe Gao, Alain Vandal, Darren Svirkis, Andrew Hill

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Background: Post-haemorrhoidectomy pain is concerned by patients/clinicians. Minimizing the postoperation pain is highly interested clinically. Combinations of topical cream targeting three hypothesised post-haemorrhoidectomy pain mechanisms were developed and their effectiveness were evaluated. Specifically, a multi-centred double-blinded randomized clinical trial (RCT) was conducted in adults undergoing excisional haemorrhoidectomy. The primary analysis was conveyed on the data collected to evaluate the effectiveness of the combinations of topical cream targeting three hypothesized pain mechanisms after the operations. Methods: 192 patients were randomly allocated to 4 arms (each arm has 48 patients), and each arm was provided with pain cream 10% metronidazole (M), M and 2% diltiazem (MD), M with 4% lidocaine (ML), or MDL, respectively. Patients were instructed to apply topical treatments three times a day for 7 days, and record outcomes for 14 days after the operations. The primary outcome was VAS pain on day 4. Covariates and models were selected in the blind review stage. Multiple imputations were applied for the missingness. LMER, GLMER models together with natural splines were applied. Sandwich estimators and Wald statistics were used. P-values < 0.05 were considered as significant. Conclusions: The addition of topical lidocaine or diltiazem to metronidazole does not add any benefit. ML had significantly better pain and recovery scores than combination MDL. Multimodal topical analgesia with ML after haemorrhoidectomy could be considered for further evaluation. Further trials considering only 3 arms (M, ML, MD) might be worth exploring.

Keywords: RCT, primary analysis, multiple imputation, pain scores, haemorrhoidectomy, analgesia, lmer

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Authors: Katyana A. Vert-Pre, James T. Thorson, Thomas Trancart, Eric Feunteun

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In marine ecosystems, spatial and temporal species structure is an important component of ecosystems’ response to anthropological and environmental factors. Although spatial distribution patterns and fish temporal series of abundance have been studied in the past, little research has been allocated to the joint dynamic spatio-temporal functional patterns in marine ecosystems and their use in multispecies management and conservation. Each species represents a function to the ecosystem, and the distribution of these species might not be random. A heterogeneous functional distribution will lead to a more resilient ecosystem to external factors. Applying a Vector-Autoregressive Spatio-Temporal (VAST) model for count data, we estimate the spatio-temporal distribution, shift in time, and abundance of 140 species of the Eastern English Chanel, Bay of Biscay and Mediterranean Sea. From the model outputs, we determined spatio-temporal clusters, calculating p-values for hierarchical clustering via multiscale bootstrap resampling. Then, we designed a functional map given the defined cluster. We found that the species distribution within the ecosystem was not random. Indeed, species evolved in space and time in clusters. Moreover, these clusters remained similar over time deriving from the fact that species of a same cluster often shifted in sync, keeping the overall structure of the ecosystem similar overtime. Knowing the co-existing species within these clusters could help with predicting data-poor species distribution and abundance. Further analysis is being performed to assess the ecological functions represented in each cluster.

Keywords: cluster distribution shift, European marine ecosystems, functional distribution, spatio-temporal model

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Authors: Oyegunle Oke, James Daramola, Oluwaseun Iyasere, Babatunde Modinat

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Wood shavings are the most common materials used as litter in commercial broiler production in many areas in Nigeria. A study was conducted to determine the effects of litter materials on organ weights, meat quality, footpad, and breast dermatitis of broiler chickens under hot humid climate. One hundred and eighty broiler chicks of marshal strains were randomly assigned to three treatments of wood shavings, maize cobs and chopped Panicum maximum as litter materials replicated four (4) times with 15 birds each in a completely randomized design. Data were collected on the relative body weights, meat quality, breast and foot pad dermatitis. The result showed that birds reared on chopped Panicum maximum had higher relative weight on the liver than those reared on wood shavings and maize cobs. Spleen and bursa of Fabricius were not significantly affected by litter materials. There was no significant effect of litter materials on meat quality. The relative weight of thigh of birds reared on chopped Panicum maximum, and Maize cobs were similar but higher than those reared on Wood shavings. Fresh breast weight of birds reared on wood shavings was higher than those reared on chopped Panicum maximum and maize cobs. It was concluded that chopped Panicum maximum could serve as a replacement for wood shavings as a litter material for broiler chickens.

Keywords: chickens, dermatitis, organs, litter materials

Procedia PDF Downloads 331

Authors: Ramon Alberto Paredes Camacho, Li Lu

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Sustainable batteries are possible through the development of cheaper and greener alternatives whose most feasible option is epitomized by Sodium-Ion Batteries (SIB). Na₃V₂(PO₄)₂F₃ (NVPF) an important member of the Na-superionic-conductor (NASICON) materials, has recently been in the spotlight due to its interesting electrochemical properties when used as cathode namely, high specific capacity of 128 mA h g-¹, high energy density of 507 W h Kg-¹, increased working potential at which vanadium redox couples can be activated (with an average value around 3.9 V), and small volume variation of less than 2%. These traits grant NVPF an excellent perspective as a cathode material for the next generation of sodium batteries. Unfortunately, because of its low inherent electrical conductivity and a high energy barrier that impedes the mobilization of all the available Na ions per formula, the overall electrochemical performance suffers substantial degradation, finally obstructing its industrial use. Many approaches have been developed to remediate these issues where nanostructural design, carbon coating, and ion doping are the most effective ones. This investigation is focused on enhancing the electrochemical response of NVPF by doping metal ions in the crystal lattice, substituting vanadium atoms. A facile sol-gel process is employed, with citric acid as the chelator and the carbon source. The optimized conditions circumvent fluorine sublimation, ratifying the material’s purity. One of the reasons behind the large ionic improvement is the attraction of extra Na ions into the crystalline structure due to a charge imbalance produced by the valence of the doped ions (+2), which is lower than the one of vanadium (+3). Superior stability (higher than 90% at a current density of 20C) and capacity retention at an extremely high current density of 50C are demonstrated by our doped NVPF. This material continues to retain high capacity values at low and high temperatures. In addition, full cell NVPF//Hard Carbon shows capacity values and high stability at -20 and 60ºC. Our doping strategy proves to significantly increase the ionic and electronic conductivity of NVPF even at extreme conditions, delivering outstanding electrochemical performance and paving the way for advanced high-potential cathode materials.

Keywords: sodium-ion batteries, cathode materials, NASICON, Na3V2(PO4)2F3, Ion doping

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Authors: Yunzi Chen, James Laybourne, Sarah Steven, Peter Carey, David Steel, Maria Sandinha

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Introduction: Bariatric surgery is popular with the rising incidence of obesity. Its well-known benefits include significant and rapid glycaemic control. However, cases of paradoxical worsening in diabetic retinopathy (DR) despite improved glycaemic control have been reported. Purpose: clarification on the evolution of diabetic retinopathy after bariatric surgery. Method: retrospective study of 40 patients with Type 2 diabetes who underwent bariatric surgery in a UK specialist bariatric unit between 2009 and 2011. Pre-operative and post-operative visual acuity (VA), weight, HbA1c and annual DRSS screening results were analysed. Median follow up was 50 months. Results: No significant change in VA was found during the post-operative period. 85% of patients improved HbA1c post-operatively of which 53% achieved non-diabetic HbA1c of <6.1% - despite this, 2 patients developed new DR. First post-operative screening showed 80% of patients experienced no change, 8% improved but 13% of patients developed new DR (1 case with sight-threatening maculopathy). 80% of these cases persisted up to 24 months. The proportion of patients developing new or worse DR fluctuated over time, peaking at the 3rd annual screening with 26% (15% regressed, 56% stable). The probability of developing new or worse DR postoperatively was significantly associated with a high pre-operative HbA1c (>8%) and male gender. Conclusions: bariatric surgery does not guarantee long-term improvement or prevention of DR. Asymptomatic changes in DR occurred up to 5 years postoperatively. We therefore consider it prudent to continue screening in this cohort of patients.

Keywords: bariatric surgery, diabetic retinopathy, obesity, type 2 diabetes mellitus

Procedia PDF Downloads 246

Authors: Liyang Yue, Bing Yan, James N. Monks, Rakesh Dhama, Zengbo Wang, Oleg V. Minin, Igor V. Minin

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A particle can function as a refractive lens to focus a plane wave, generating a narrow, high intensive, weak-diverging beam within a sub-wavelength volume, known as the ‘photonic jet’. Refractive index contrast (particle to background media) and scaling effect of the dielectric particle (relative-to-wavelength size) play key roles in photonic jet formation, rather than the shape of particle-lens. Waist (full width of half maximum, FWHM) of a photonic jet could be beyond the diffraction limit and smaller than the Airy disk, which defines the minimum distance between two objects to be imaged as two instead of one. Many important applications for imaging and sensing have been afforded based upon the super-resolution characteristic of the photonic jet. It is known that apodization method, in the form of an amplitude pupil-mask centrally situated on a particle-lens, can further reduce the waist of a photonic nanojet, however, usually lower its intensity at the focus due to blocking of the incident light. In this paper, the anomalously intensity-enhanced apodization effect was discovered in the near-field via numerical simulation. It was also experimentally verified by a scale model using a copper-masked Teflon cuboid solid immersion lens (SIL) with 22 mm side length under radiation of a plane wave with 8 mm wavelength. Peak intensity enhancement and the lateral resolution of the produced photonic jet increased by about 36.0 % and 36.4 % in this approach, respectively. This phenomenon may possess the scale effect and would be valid in multiple frequency bands.

Keywords: apodization, particle-lens, scattering, near-field optics

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Authors: Kathrina Aseanne Acapulco-Gomez, Shayne Julieane Morales, Tzar Francis Verame

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Mean platelet volume (MPV) is the most accurate measure of the size of platelets and is routinely measured by most automated hematological analyzers. Several studies have shown associations between MPV and cardiovascular risks and outcomes. Although its measurement may provide useful data, MPV remains to be a diagnostic tool that is yet to be included in routine clinical decision making. The aim of this systematic review and meta-analysis is to determine summary estimates of the diagnostic accuracy of mean platelet volume for the diagnosis of myocardial infarction among adult patients with angina and/or its equivalents in terms of sensitivity, specificity, diagnostic odds ratio, and likelihood ratios, and to determine the difference of the mean MPV values between those with MI and those in the non-MI controls. The primary search was done through search in electronic databases PubMed, Cochrane Review CENTRAL, HERDIN (Health Research and Development Information Network), Google Scholar, Philippine Journal of Pathology, and Philippine College of Physicians Philippine Journal of Internal Medicine. The reference list of original reports was also searched. Cross-sectional, cohort, and case-control articles studying the diagnostic performance of mean platelet volume in the diagnosis of acute myocardial infarction in adult patients were included in the study. Studies were included if: (1) CBC was taken upon presentation to the ER or upon admission (within 24 hours of symptom onset); (2) myocardial infarction was diagnosed with serum markers, ECG, or according to accepted guidelines by the Cardiology societies (American Heart Association (AHA), American College of Cardiology (ACC), European Society of Cardiology (ESC); and, (3) if outcomes were measured as significant difference AND/OR sensitivity and specificity. The authors independently screened for inclusion of all the identified potential studies as a result of the search. Eligible studies were appraised using well-defined criteria. Any disagreement between the reviewers was resolved through discussion and consensus. The overall mean MPV value of those with MI (9.702 fl; 95% CI 9.07 – 10.33) was higher than in those of the non-MI control group (8.85 fl; 95% CI 8.23 – 9.46). Interpretation of the calculated t-value of 2.0827 showed that there was a significant difference in the mean MPV values of those with MI and those of the non-MI controls. The summary sensitivity (Se) and specificity (Sp) for MPV were 0.66 (95% CI; 0.59 - 0.73) and 0.60 (95% CI; 0.43 – 0.75), respectively. The pooled diagnostic odds ratio (DOR) was 2.92 (95% CI; 1.90 – 4.50). The positive likelihood ratio of MPV in the diagnosis of myocardial infarction was 1.65 (95% CI; 1.20 – 22.27), and the negative likelihood ratio was 0.56 (95% CI; 0.50 – 0.64). The intended role for MPV in the diagnostic pathway of myocardial infarction would perhaps be best as a triage tool. With a DOR of 2.92, MPV values can discriminate between those who have MI and those without. For a patient with angina presenting with elevated MPV values, it is 1.65 times more likely that he has MI. Thus, it is implied that the decision to treat a patient with angina or its equivalents as a case of MI could be supported by an elevated MPV value.

Keywords: mean platelet volume, MPV, myocardial infarction, angina, chest pain

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Authors: Zoe M. G. Skalkos, Sam N. Dowland, James U. Van Dyke, Camilla. M. Whittington

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Syngnathid fishes (seahorses, pipefishes, and seadragons) are unique because embryos develop on or in the male in a specialised brooding structure. Many seahorse species are endangered or vulnerable, while others are popular in the ornamental fish trade. Seahorses are capable of nutrient provisioning (patrotrophy) of lipids during pregnancy via their fully enclosed brood pouch. Protein is vital for gene regulation and tissue growth during embryogenesis. We tested the hypothesis that protein is paternally transported to developing embryos during pregnancy in the Australian Pot-bellied seahorse, Hippocampus abdominalis. We compared the dry masses and nitrogen content in recently fertilised H. abdominalis embryos and newborns. We calculated an updated patrotrophy index, 1.34, but without a significant difference in dry mass between the two developmental stages. There was, however, a significant increase in total protein content from recently fertilised embryos to neonates. This suggests paternal protein transport is essential for H. abdominalis embryogenesis because protein yolk reserves are depleted by embryonic metabolism, and supplementation is required. This study is the first to provide evidence for paternal protein transport during pregnancy in seahorses. It furthers our understanding of the paternal influence on embryonic development in male pregnancy and how a protein-deficient diet during pregnancy may limit the allocation of resources to embryos, reducing offspring fitness. This research contributes to a deeper understanding of the fundamental reproductive biology of seahorses, which can help improve conservation and farming production outcomes.

Keywords: brood pouch, embryonic provisioning, nitrogen, parentotrophy, paternal investment, reproduction

Procedia PDF Downloads 66

Authors: Andrés Quiroz, Emilio Hormazábal, Ana Mutis, Fernando Ortega, Loreto Méndez, Leonardo Parra

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Red clover root borer, Hylastinus obscurus Marsham (Coleoptera: Curculionidae), is the main insect pest associated to red clover, Trifolium pratense L. An average of 1.5 H. obscurus per plant can cause 5.5% reduction in forage yield in pastures of two to three years old. Moreover, insect attack can reach 70% to 100% of the plants. To our knowledge, there is no a chemical strategy for controlling this pest. Therefore alternative strategies for controlling H. obscurus are a high priority for red clover producers. One of this alternative is related to the study of secondary metabolites involved in intrinsic chemical defenses developed by plants, such as isoflavonoids. The isoflavonoids formononetin and daidzein have elicited an antifeedant and phagostimult effect on H. obscurus respectively. However, we do not know how is the dynamic variation of these isoflavonoids under field conditions. The main objective of this work was to evaluate the variation of the antifeedant isoflavonoids formononetin, the phagostimulant isoflavonoids daidzein, and their respective glycosides over time in different ecotypes of red clover. Fourteen red clover ecotypes (8 cultivars and 6 experimental lines), were collected at INIA-Carillanca (La Araucanía, Chile). These plants were established in October 2015 under irrigated conditions. The cultivars were distributed in a randomized complete block with three replicates. The whole plants were sampled in four times: 15th October 2016, 12th December 2016, 27th January 2017 and 16th March 2017 with sufficient amount of soil to avoid root damage. A polar fraction of isoflavonoid was obtained from 20 mg of lyophilized root tissue extracted with 2 mL of 80% MeOH for 16 h using an orbital shaker in the dark at room temperature. After, an aliquot of 1.4 mL of the supernatant was evaporated, and the residue was resuspended in 300 µL of 45% MeOH. The identification and quantification of isoflavonoid root extracts were performed by the injection of 20 µL into a Shimadzu HPLC equipped with a C-18 column. The sample was eluted with a mobile phase composed of AcOH: H₂O (1:9 v/v) as solvent A and CH₃CN as solvent B. The detection was performed at 260 nm. The results showed that the amount of aglycones was higher than the respective glycosides. This result is according to the biosynthetic pathway of flavonoids, where the formation of glycoside is further to the glycosides biosynthesis. The amount of formononetin was higher than daidzein. In roots, where H. obscurus spent the most part of its live cycle, the highest content of formononetin was found in G 27, Pawera, Sabtoron High, Redqueli-INIA and Superqueli-INIA cvs. (2.1, 1.8, 1.8, 1.6 and 1.0 mg g⁻¹ respectively); and the lowest amount of daidzein were found Superqueli-INIA (0.32 mg g⁻¹) and in the experimental line Sel Syn Int4 (0.24 mg g⁻¹). This ecotype showed a high content of formononetin (0.9 mg g⁻¹). This information, associated with cultural practices, could help farmers and breeders to reduce H. obscurus in grassland, selecting ecotypes with high content of formononetin and low amount of daidzein in the roots of red clover plants. Acknowledgements: FONDECYT 1141245 and 11130715.

Keywords: daidzein, formononetin, isoflavonoid glycosides, trifolium pratense

Procedia PDF Downloads 191

Authors: Franco Lorenzo D. Morales

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‘Toshi-no-sakon,’ which translates to as ‘age gap marriage,’ is a term that has been popularized by celebrity couples in the Japanese entertainment industry. Japan is distinct for a developed nation for its rapidly aging population, declining marital and fertility rates, and the reinforcement of traditional gender roles. Statistical data has shown that the average age of marriage in Japan is increasing every year, showing a growing tendency for late marriage. As a result, the government has been trying to curb the declining trends by encouraging marriage and childbirth among the populace. This graduate thesis seeks to analyze the ‘toshi-no-sakon’ phenomenon in lieu of Japan’s current economic and social situation, and to see what the implications are for these kinds of married couples. This research also seeks to expound more on age gaps within married couples, which is a factor rarely-touched upon in Japanese family studies. A literature review was first performed in order to provide a framework to study ‘toshi-no-sakon’ from the perspective of four fields of study—marriage, family, aging, and gender. Numerous anonymous online statements by ‘toshi-no-sakon’ couples were then collected and analyzed, which brought to light a number of concerns. Couples wherein the husband is the older partner were prioritized in order to narrow down the focus of the research, and ‘toshi-no-sakon’ is only considered when the couple’s age gap is ten years or more. Current findings suggest that one of the perceived merits for a woman to marry an older man is that financial security would be guaranteed. However, this has been shown to be untrue as a number of couples express concern regarding their financial situation, which could be attributed to their husband’s socio-economic status. Having an older husband who is approaching the age of retirement presents another dilemma as the wife would be more obliged to provide care for her aging husband. This notion of the wife being a caregiver likely stems from an arrangement once common in Japanese families in which the wife must primarily care for her husband’s elderly parents. Childbearing is another concern as couples would be pressured to have a child right away due to the age of the husband, in addition to limiting the couple’s ideal number of children. This is another problematic aspect as the husband would have to provide income until his child has finished their education, implying that retirement would have to be delayed indefinitely. It is highly recommended that future studies conduct face-to-face interviews with couples and families who fall under the category of ‘toshi-no-sakon’ in order to gain a more in-depth perspective into the phenomenon and to reveal any undiscovered trends. Cases wherein the wife is the older partner in the relationship should also be given focus in future studies involving ‘toshi-no-sakon’.

Keywords: age gap, family structure, gender roles, marriage trends

Procedia PDF Downloads 337

Authors: Marija Knez, James C.R. Stangoulis, Manja Zec, Zoran Pavlovic, Jasmina D. Martacic, Mirjana Gurinovic, Maria Glibetic

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Background: Zinc is an essential micronutrient for humans with important physiological functions. A sensitive and specific biomarker for assessing Zn status is still needed. Objective: The major aim of this study was to examine if the changes in the content of plasma phospholipid LA, DGLA and LA: DGLA ratio can be used to efficiently predict the dietary Zn intake and plasma Zn status of humans. Methods: The study was performed on apparently healthy human volunteers. The dietary Zn intake was assessed using 24h recall questionnaires. Plasma phospholipid fatty acid analysis was done by gas chromatography and plasma analysis of minerals by atomic absorption spectrometry. Biochemical, anthropometrical and hematological parameters were assessed. Results: No significant relationship was found between the dietary and plasma zinc status (r=0.07; p=0.6). There is a statistically significant correlation between DGLA and plasma Zn (r=0.39, p=0.00). No relationship was observed between the linoleic acid and plasma Zn, while there was a significant negative correlation between LA: DGLA ratio and plasma Zn status (r=-0.35, p=0.01). Similarly, there were statistically significant difference in DGLA status (p=0.004) and LA: DGLA ratio (p=0.042) between the Zn formed groups. Conclusions: This study is an initial step in evaluating LA: DGLA ratio as a biomarker of Zn status in humans. The results are encouraging as they show that concentration of DGLA is decreased and LA: DGLA ratio increased in people with lower dietary Zn intake. However, additional studies are needed to fully examine the sensitivity of this biomarker.

Keywords: dietary Zn intake Zinc, fatty acid composition, LA: DGLA, healthy population, plasma Zn status, Zn biomarker

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Authors: Abigail Tan, Heng Liang Tan, Vanessa Ding, James Hui, Eng Hin Lee, Andre Choo

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Introduction: Comparative oncology investigates the similarities in spontaneous carcinogenesis between humans and animals, in order to identify treatments that can benefit these patients. Companion animals (CA), like canines and felines, are of special interest when it comes to studying human cancers due to their exposure to the same environmental factors and develop tumours with similar features. The purpose of this study is to explore the cross-reactivity of monoclonal antibodies (mAbs) across cancers in humans and CA. Material and Methods: A panel of CA mAbs generated in the lab was screened on multiple human cancer cell lines through flow cytometry to identify for positive binders. Shortlisted candidates were then characterised by biochemical and functional assays e.g., antibody-drug conjugate (ADC) and western blot assays, including glycan studies. Results: Candidate mAb KP52 was generated from whole-cell immunisation using feline mammary carcinoma. KP52 showed strong positive binding to human cancer cells, such as breast cancer and ovarian cancer. Furthermore, KP52 demonstrated strong killing ( > 50%) as an ADC with Saporin as the payload. Western blot results revealed the molecular weight of the antigen targets to be approximately 45kD and 50kD under reduced conditions. Glycan studies suggest that the epitope is glycan in nature, specifically an O-linked glycan. Conclusion: Candidate mAb KP52 has a therapeutic potential as an ADC against feline mammary cancer, human ovarian cancer, human mammary cancer, human pancreatic cancer, and human gastric cancer.

Keywords: ADC, comparative oncology, mAb, therapeutic

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Authors: Andrés Quiroz, Emilio Hormazabal, Ana Mutis, Fernando Ortega, Manuel Chacón-Fuentes, Leonardo Parra

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Red clover (Trifolium pratense L.) is an important forage species in temperate regions of the world. The main limitation of this species worldwide is a lack of persistence related to the high mortality of plants due to a complex of biotic and abiotic factors, determining a life span of two or three seasons. Because of the importance of red clover in Chile, a red clover breeding program was started at INIA Carillanca Research Center in 1989, with the main objective of improving the survival of plants, forage yield, and persistence. The main selection criteria for selecting new varieties have been based on agronomical parameters and biotic factors. The main biotic factor associated with red clover mortality in Chile is Hylastinus obscurus (Coleoptera: Curculionidae). Both larval and adults feed on the roots, causing weakening and subsequent death of clover plants. Pesticides have not been successful for controlling infestations of this root borer. Therefore, alternative strategies for controlling this pest are a high priority for red clover producers. Currently, the role of semiochemical in the interaction between H. obscurus and red clover plants has been widely studied for our group. Specifically, from the red clover foliage has been identified limonene is eliciting repellency from the root borer. Limonene is generated in the plant from two independent biosynthetic pathways, the mevalonic acid, and deoxyxylulose pathway. Mevalonate pathway enzymes are localized in the cytosol, whereas the deoxyxylulose phosphate pathway enzymes are found in plastids. In summary, limonene can be determinated by enzymatic bioassay using GPP as substrate and by limonene synthase expression. Therefore, the main objective of this work was to study genetic variation of limonene in material provided by INIA´s Red Clover breeding program. Protein extraction was carried out homogenizing 250 mg of leave tissue and suspended in 6 mL of extraction buffer (PEG 1500, PVP-30, 20 mM MgCl2 and antioxidants) and stirred on ice for 20 min. After centrifugation, aliquots of 2.5 mL were desalted on PD-10 columns, resulting in a final volume of 3.5 mL. Protein determination was performed according to Bradford with BSA as a standard. Monoterpene synthase assays were performed with 50 µL of protein extracts transferred into gas-tight 2 mL crimp seal vials after addition of 4 µL MgCl₂ and 41 µL assay buffer. The assay was started by adding 5 µL of a GPP solution. The mixture was incubated for 30 min at 40 °C. Biosynthesized limonene was quantified in a GC equipped with a chiral column and using synthetic R and S-limonene standards. The enzymatic the production of R and S-limonene from different Superqueli-Carillanca genotypes is shown in this work. Preliminary results showed significant differences in limonene content among the genotypes analyzed. These results constitute an important base for selecting genotypes with a high content of this repellent monoterpene towards H. obscurus.

Keywords: head space, limonene enzymatic determination, red clover, Hylastinus obscurus

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Authors: Nana Segu Acquaah-Harrison, James Osei Mensah, Richard Aidoo, David Amponsah, Amy Buah, Gilbert Aboagye

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The study aimed at assessing the feasibility of commercial meat rabbit production in the Kumasi Metropolis of Ghana. Structured and unstructured questionnaires were utilized in obtaining information from two hundred meat consumers and 15 meat rabbit farmers. Data were analyzed using Net Present Value (NPV), Internal Rate of Return (IRR), Benefit Cost Ratio (BCR)/Profitability Index (PI) technique, percentages and chi-square contingency test. The study found that the current demand for rabbit meat is low (36%). The desirable nutritional attributes of rabbit meat and other socio economic factors of meat consumers make the potential demand for rabbit meat high (69%). It was estimated that GH¢5,292 (approximately $ 2672) was needed as a start-up capital for a 40-doe unit meat rabbit farm in Kumasi Metropolis. The cost of breeding animals, housing and equipment formed 12.47%, 53.97% and 24.87% respectively of the initial estimated capital. A Net Present Value of GH¢ 5,910.75 (approximately $ 2984) was obtained at the end of the fifth year, with an internal rate return and profitability index of 70% and 1.12 respectively. The major constraints identified in meat rabbit production were low price of rabbit meat, shortage of fodder, pest and diseases, high cost of capital, high cost of operating materials and veterinary care. Based on the analysis, it was concluded that meat rabbit production is feasible in the Kumasi Metropolis of Ghana. The study recommends embarking on mass advertisement; farmer association and adapting to new technologies in the production process will help to enhance productivity.

Keywords: feasibility, commercial meat rabbit, production, Kumasi, Ghana

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Authors: Jeffrey Ho, Scott Joing, Paul Nystrom, William Heegaard, Danielle Hart, David Plummer, James Miner

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Body-Worn Cameras (BWCs) are used in public safety to record encounters. They are shown to enhance the accuracy of documentation in virtually every situation. They are not widely used in medical encounters in part because of concern for patient acceptance. The goal of this pilot study was to determine if BWC use is acceptable to the patient. This was a prospective, observational study of the AXON Flex BWC (TASER International, Scottsdale, AZ) conducted at an urban, Level 1 Trauma Center Emergency Department (ED). The BWC was worn by Emergency Physicians (EPs) on their shifts during a 30-day period. The BWC was worn at eye-level mounted on a pair of clear safety glasses. Patients seen by the EP were enrolled in the study by a trained research associate. Patients who were <18 years old, who were with other people in the exam room, did not speak English, were critically ill, had chief complaints involving genitalia or sexual assault, were considered to be vulnerable adults, or with an altered mental status were excluded. Consented patients were given a survey after the encounter to determine their perception of the BWC. The questions asked involved the patients’ perceptions of a BWC being present during their interaction with their EP. Data were analyzed with descriptive statistics. There were 417 patients enrolled in the study. 3/417 (0.7%) patients were intimidated by the BWC, 1/417 (0.2%) was nervous because of the BWC, 0/417 (0%) were inhibited from telling the EP certain things because of the BWC, 57/417 (13.7%) patients did not notice the device, and 305/417 (73.1%) patients were had a favorable perception about the BWC being used during their encounter. The use of BWCs appears feasible in the ED, with largely favorable perceptions and acceptance of the device by the patients. Further study is needed to determine the best use and practices of BWCs during ED patient encounters.

Keywords: body-worn camera, documentation, patient satisfaction, video

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Authors: James Banda, Jupiter Simbeye, Essau Chisale, Geoffrey Kanyerere, Kings Kamtambe

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Improved solar tent dryers for processing small fish species were designed to reduce post-harvest fish losses and improve supply of quality fish products in the southern part of Lake Malawi under CultiAF project. A comparative analysis of the quality of Diplotaxodon (Ndunduma) from Lake Malawi processed in solar tent dryer and open sun drying was conducted using proximate analysis, microbial analysis and sensory evaluation. Proximates for solar tent dried fish and open sun dried fish in terms of proteins, fats, moisture and ash were 63.3±0.15% and 63.3±0.34%, 19.6±0.09% and 19.9±0.25%, 8.3±0.12% and 17.0±0.01%, and 15.6±0.61% and 21.9±0.91% respectively. Crude protein and crude fat showed non-significant differences (p = 0.05), while moisture and ash content were significantly different (p = 001). Open sun dried fish had significantly higher numbers of viable bacteria counts (5.2×10⁶ CFU) than solar tent dried fish (3.9×10² CFU). Most isolated bacteria from solar tent dried and open sun dried fish were 1.0×10¹ and 7.2×10³ for Total coliform, 0 and 4.5 × 10³ for Escherishia coli, 0 and 7.5 × 10³ for Salmonella, 0 and 5.7×10² for shigella, 4.0×10¹ and 6.1×10³ for Staphylococcus, 1.0×10¹ and 7.0×10² for vibrio. Qualitative evaluation of sensory properties showed higher acceptability of 3.8 for solar tent dried fish than 1.7 for open sun dried fish. It is concluded that promotion of solar tent drying in processing small fish species in Malawi would support small-scale fish processors to produce quality fish in terms of nutritive value, reduced microbial contamination, sensory acceptability and reduced moisture content.

Keywords: diplotaxodon, Malawi, open sun drying, solar tent drying

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Authors: Clementina Ebere Okoro, Olumuyiwa Adeyemi Owolabi, Doris Bola James, Aloysius Nwabugo Maduforo, Andrew Lingililani Mbewe, Christopher Osaruwanmwen Isokpunwu

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Poor dietary practices and malnutrition, including severe acute malnutrition among under-five children in Nigeria has remained a great public health concern. This study assessed infant and young child feeding practices and nutritional status of under-five children to determine the prevalence of malnutrition of under-five children in Kuje area council, Abuja. The study was a cross-sectional study. Multi-stage sampling techniques was used in selecting the population that was studied. Probability proportion by size was applied in choosing 30 clusters for the survey using ENA for SMART software 2011 version. Questionnaires were used to obtain information from the population, while appropriate equipment was used for measurements of anthropometric parameters. The data was also subjected to statistical analysis. Results were presented in tables and figures. The result showed that 96.7% of the children were breastfed, 30.6% had early initiation to breastfeeding within first hour of birth and 22.4% were breastfed exclusively up to 6 months, 69.8% fed infants’ colostrum, while 30.2% discarded colostrum. About half of the respondents (49.1%) introduced complementary feeding before six months and 23.2% introduced it after six months while 27.7% had age appropriate timely introduction of complementary feeding. The anthropometric result showed that the prevalence of global acute malnutrition (GAM) was 12.8%, severe wasting prevalence was 5.4%, moderate wasting was 7.4%, underweight was 24.4%, stunting was 40.3% and overweight was 7.0%. The result showed that there is a high prevalence of malnutrition among under-five children in Kuje

Keywords: malnutrition, under five children, breastfeeding, complementary feeding

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Authors: Babatunde James Falaye, Shi Hai Dong, Kayode John Oyewumi

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We study the effects of oblateness up to J4 of the primaries and power-law density profile (PDP) on the linear stability of libration location of an innitesimal mass within the framework of restricted three body problem (R3BP), by using a more realistic model in which a disc with PDP is rotating around the common center of the system mass with perturbed mean motion. The existence and stability of triangular equilibrium points have been explored. It has been shown that triangular equilibrium points are stable for 0 < μ < μc and unstable for μc ≤ μ ≤ 1/2, where c denotes the critical mass parameter. We find that, the oblateness up to J2 of the primaries and the radiation reduces the stability range while the oblateness up to J4 of the primaries increases the size of stability both in the context where PDP is considered and ignored. The PDP has an eect of about ≈0:01 reduction on the application of c to Earth-Moon and Jupiter-Moons systems. We find that the comprehensive effects of the perturbations have a stabilizing proclivity. However, the oblateness up to J2 of the primaries and the radiation of the primaries have tendency for instability, while coecients up to J4 of the primaries have stability predisposition. In the limiting case c = 0, and also by setting appropriate parameter(s) to zero, our results are in excellent agreement with the ones obtained previously. Libration points play a very important role in space mission and as a consequence, our results have a practical application in space dynamics and related areas. The model may be applied to study the navigation and station-keeping operations of spacecraft (innitesimal mass) around the Jupiter (more massive) -Callisto (less massive) system, where PDP accounts for the circumsolar ring of asteroidal dust, which has a cloud of dust permanently in its wake.

Keywords: libration points, oblateness, power-law density profile, restricted three-body problem

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Authors: Nicholas Anarfi Bofah, James Damsere- Derry

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There is increasing interest among institutions, governments, and international organisations to combat congestion, reduce contribution to green gases and provide sustainable urban transportation. College campuses are a preeminent setting for promoting active commuting to ameliorate a community's healthy lifestyle. Cycling is an important physical activity and has a long-term effect on health, and it is considered one of the top five interventions to reduce the prevalence of non-communicable diseases. The main objectives of the research were: (i) to identify students’ attitudes and behavior toward cycling usage, (ii) to identify barriers and opportunities for cycling on a university campus, and (iii) to construct tangible policy recommendations for promoting cycling in the vicinity of the university. The data used in this study were obtained from a survey conducted among students at the Kwame Nkrumah University of Science and Technology (KNUST) in Kumasi between May 2022 and September 2022. A convenient sampling method was used to recruit and interview 398 participants. Two survey assistants who are former students of the university were engaged to administer the questionnaires randomly to students at the selected locations. Descriptive statistics were employed in the analysis of the data. Out of the 398 questionnaires, bicycle ridership and ownership among university students were 57% and 39%, respectively. Generally, the desire to use a bicycle as a mode of transport on campus was 36%. The desire to use a bicycle on campus was more prevalent among males 41% compared to females 30%. There is a high potential for increasing bicycle use among students. Recommendations include the provision of bicycle lanes, public education on the use of bicycles, and a campus bicycle-sharing program.

Keywords: sustainable development, cycling, university campus, bicycle

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Authors: James Ponniah

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Christianity is the largest religious tradition of the world. What makes Christianity a world religion is its characteristics of universality and particularity. Its universality and particularity are closely interrelated. Its university is realized and embodied in its particularities and its particularity is recognized and legitimized through its universality. This paper focuses on the dimension of the particularity of Christianity in that it looks at the particularized ideas and discourses of Christian thinking in India in the 20th century and pays attention to the differing shifts and new shades of meaning in Indian Christian notion of God. Drawing upon the writings of select Indian theologians such as Brahmabandhab Upadhyaya, Sundar Sing, A.J Appasamy, Raymond Panikkar, Amalorpavadass and George Soares Prabhhu, this paper delves into how the contexts—be it personal, political, historical or ecclesial—bear upon the way Indian theologians have conceived and constructed the notion of God in their work. Focusing upon how they responded to the signs of their time through their theological narratives, the paper argues that the religion of Christianity can sustain its universality only when it translates its key notions such as God into indigenous categories and local idioms and thus makes itself relevant to the people among whom it is spread. Monotheistic God of Christianity has to accommodate plurality of expressions if Christian idea God has to capture and convey everyone’s experience of God. The case of Indian Christianity then reveals that a monolithic world religion will be experienced and recognised as truly universal only when it sheds its homogeneity and assumes a heterogeneous portrait through the acquisition of local idioms. Allowing culturally diverse idioms to influence theological categories is not inconsequential to—‘accommodating differences and accepting diversities,’ an issue we encounter within and beyond religious domains in our contemporary times.

Keywords: concept of God, heterogeneity, Indian Christianity, indigenous categories

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Authors: Andile Mkhohlakali, Tien-Chien Jen, James Tshilongo, Happy Mabowa

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Among different parameters, oxygen is one of the most important analytes of interest, dissolved oxygen (DO) concentration is very crucial and significant for various areas of physical, chemical, and environmental monitoring. Herein we report oxygen-sensitive luminophores -based lanthanum(III) trifluoromethanesulfonate), [La]³⁺ was encapsulated into SiO₂-based xerogel matrix. The nanosensor is composed of organically modified silica nanoparticles, doped with the luminescent oxygen–sensitive lanthanum(III) trifluoromethanesulfonate complex. The precursor materials used for sensing film were triethyl ethoxy silane (TEOS) and (3-Mercaptopropyltriethoxysilane) (MPTMS- TEOS) used for SiO2-baed matrices. Brunauer–Emmett–Teller (BET), and BJH indicate that the SiO₂ transformed from microporous to mesoporous upon the addition of La³⁺ luminophore with increased surface area (SBET). The typical amorphous SiO₂ based xerogels were revealed with X-Ray diffraction (XRD) and Selected Area Electron Diffraction (SAED) analysis. Scanning electron microscope- (SEM) and transmission electron microscope (TEM) showed the porous morphology and reduced particle for SiO₂ and La-SiO₂ xerogels respectively. The existence of elements, siloxane networks, and thermal stability of xerogel was confirmed by energy dispersive spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), and Thermographic analysis (TGA). UV-Vis spectroscopy and photoluminescence (PL) have been used to characterize the optical properties of xerogels. La-SiO₂ demonstrates promising characteristic features of an active sensing film for dissolved oxygen in the water. Keywords: Sol-gel, ORMOSILs, encapsulation, Luminophores quenching, O₂-sensing

Keywords: sol-gel, ORMOSILs, luminophores quenching, O₂-sensing

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Authors: Delphine Morales, Florian Lombart, Agathe Truchot, Pauline Maire, Pascale Vigneron, Antoine Galmiche, Catherine Lok, Muriel Vayssade

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Targeted therapy molecules are used as a first-line treatment for metastatic melanoma with B-Raf mutation. Nevertheless, these molecules can cause side effects to patients and are efficient on 50 to 60 % of them. Indeed, melanoma cell sensitivity to targeted therapy molecules is dependent on tumor microenvironment (cell-cell and cell-extracellular matrix interactions). To better unravel factors modulating cell sensitivity to B-Raf inhibitor, we have developed and compared several melanoma models: from metastatic melanoma cells cultured as monolayer (2D) to a co-culture in a 3D dermal equivalent. Cell response was studied in different melanoma cell lines such as SK-MEL-28 (mutant B-Raf (V600E), sensitive to Vemurafenib), SK-MEL-3 (mutant B-Raf (V600E), resistant to Vemurafenib) and a primary culture of dermal human fibroblasts (HDFn). Assays have initially been performed in a monolayer cell culture (2D), then a second time on a 3D dermal equivalent (dermal human fibroblasts embedded in a collagen gel). All cell lines were treated with Vemurafenib (a B-Raf inhibitor) for 48 hours at various concentrations. Cell sensitivity to treatment was assessed under various aspects: Cell proliferation (cell counting, EdU incorporation, MTS assay), MAPK signaling pathway analysis (Western-Blotting), Apoptosis (TUNEL), Cytokine release (IL-6, IL-1α, HGF, TGF-β, TNF-α) upon Vemurafenib treatment (ELISA) and histology for 3D models. In 2D configuration, the inhibitory effect of Vemurafenib on cell proliferation was confirmed on SK-MEL-28 cells (IC50=0.5 µM), and not on the SK-MEL-3 cell line. No apoptotic signal was detected in SK-MEL-28-treated cells, suggesting a cytostatic effect of the Vemurafenib rather than a cytotoxic one. The inhibition of SK-MEL-28 cell proliferation upon treatment was correlated with a strong expression decrease of phosphorylated proteins involved in the MAPK pathway (ERK, MEK, and AKT/PKB). Vemurafenib (from 5 µM to 10 µM) also slowed down HDFn proliferation, whatever cell culture configuration (monolayer or 3D dermal equivalent). SK-MEL-28 cells cultured in the dermal equivalent were still sensitive to high Vemurafenib concentrations. To better characterize all cell population impacts (melanoma cells, dermal fibroblasts) on Vemurafenib efficacy, cytokine release is being studied in 2D and 3D models. We have successfully developed and validated a relevant 3D model, mimicking cutaneous metastatic melanoma and tumor microenvironment. This 3D melanoma model will become more complex by adding a third cell population, keratinocytes, allowing us to characterize the epidermis influence on the melanoma cell sensitivity to Vemurafenib. In the long run, the establishment of more relevant 3D melanoma models with patients’ cells might be useful for personalized therapy development. The authors would like to thank the Picardie region and the European Regional Development Fund (ERDF) 2014/2020 for the funding of this work and Oise committee of "La ligue contre le cancer".

Keywords: 3D human skin model, melanoma, tissue engineering, vemurafenib efficiency

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Authors: Ange Weinrabe, James Tran, Ian B. Hickie

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Risk-taking behaviour is common during youth. In the time between adolescence and early adulthood, young people (aged 15-25 years) are more vulnerable to mood disorders, such as anxiety and depression. What impact does an emerging mood disorder have on decision-making in youth at critical decision points in their lives? In this article, we explore the impact of risk and ambiguity on youth decision-making in a clinical setting using a well-known economic experiment. At two time points, separated by six to eight weeks, we measured risky and ambiguous choices concurrently with findings from three psychological questionnaires, the 10-item Kessler Psychological Distress Scale (K10), the 17-item Quick Inventory of Depressive Symptomatology Adolescent Version (QIDS-A17), and the 12-item Somatic and Psychological Health Report (SPHERE-12), for young help seekers aged 16-25 (n=30, mean age 19.22 years, 19 males). When first arriving for care, we found that 50% (n=15) of participants experienced severe anxiety (K10 ≥ 30) and were severely depressed (QIDS-A17 ≥ 16). In Session 2, taking attrition rates into account (n=5), we found that 44% (n=11) remained severe across the full battery of questionnaires. When applying multiple regression analyses of the pooled sample of observations (N=55), across both sessions, we found that participants who rated severely anxious avoided making risky decisions. We suggest there is some statistically significant (although weak) (p=0.09) relation between risk and severe anxiety scores as measured by K10. Our findings may support working with novel tools with which to evaluate youth experiencing an emerging mood disorder and their cognitive capacities influencing decision-making.

Keywords: anxiety, decision-making, risk, adolescence

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Authors: Nisha James, Shubha Ranganathan

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One of the most poignant forms of organized crime against women, which has rarely made it to the world of Indian cinema, is that of sex trafficking, i.e. the forcible involvement of women in the sex trade through fraud or coercion (Hughes, 2005). In the space of Indian cinema, much of the spotlight has been on the sensational drug trafficking and gang mafia of Bombay. During our research on sex trafficking, the rehabilitated women interviewed often expressed strong criticism about mass media’s naive portrayal of prostitutes as money-minting, happy and sexually driven women. They argued that this unrealistic portrayal ignored the fact that this was not a reality for the majority of trafficked women. Given the gravity of sex trafficking as a human rights issue, it is, therefore, refreshing to see three recent films on sex trafficking in Indian Languages – Naa Bangaaru Talli (2014, Telugu), Mardaani (2014, Hindi) and Lakshmi (2014, Hindi). This paper reviews these three films to explore the portrayal of the everyday reality of trafficking for women. Film analysis was used to understand the representation of psychological issues in the media. The strength of these movies starts with their inspirations which are of true stories and that they are all aimed at bringing awareness about the issue of sex trafficking, which is a rising social evil in Indian society though none of the three films move to portray the next phase of rehabilitation and reintegration of victims, which is a very complex and important process in the life of a survivor. According to findings, survivors of sex trafficking find the rehabilitation and reintegration into society to be a slow and tough part of their life as they continuously face stigma and social exclusion and have to strive to live against all odds of non-acceptance starting from their family.

Keywords: film review, Indian films, sex trafficking, survivors

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Authors: Khaled Al-Badani, James Ren, Lisa Li, David Allanson

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Droplet formation is an important process in many engineering systems and manufacturing procedures, which includes welding, biotechnologies, 3D printing, biochemical, biomedical fields and many more. The volume and the characteristics of droplet formation are generally depended on various material properties, microfluidics and fluid mechanics considerations. Hence, a detailed investigation of this process, with the aid of numerical computational tools, are essential for future design optimization and process controls of many engineering systems. This will also improve the understanding of changes in the properties and the structures of materials, during the formation of the droplet, which is important for new material developments to achieve different functions, pending the requirements of the application. For example, the shape of the formed droplet is critical for the function of some final products, such as the welding nugget during Capacitor Discharge Welding process, or PLA 3D printing, etc. Although, most academic journals on droplet formation, focused on issued with material transfer rate, surface tension and residual stresses, the general emphasis on the characteristics of droplet shape has been overlooked. The proposed work for this project will examine theoretical methodologies, experimental techniques, and numerical modelling, using ANSYS FLUENT, to critically analyse and highlight optimization methods regarding the formation of pendant droplet. The project will also compare results from published data with experimental and numerical work, concerning the effects of key material parameters on the droplet shape. These effects include changes in heating/cooling rates, solidification/melting progression and separation/break-up times. From these tests, a set of objectives is prepared, with an intention of improving quality, stability and productivity in modelling metal welding and 3D printing.

Keywords: computer modelling, droplet formation, material distortion, materials forming, welding

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Authors: Matthias Walluch, José Alberto Rodríguez, Christopher Giehl, Gunther Arnold, Daniela Ehgartner

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Dynamic mechanical analysis (DMA) is a powerful method to characterize viscoelastic properties and phase transitions for a wide range of materials. It is often used to characterize polymers and their temperature-dependent behavior, including thermal transitions like the glass transition temperature Tg, via determination of storage and loss moduli in tension (Young’s modulus, E) and shear or torsion (shear modulus, G) or other testing modes. While production and application temperatures for polymers are often limited to several hundred degrees, material properties of glasses usually require characterization at temperatures exceeding 600 °C. This contribution highlights a high temperature setup for rotational and oscillatory rheometry as well as for DMA in different modes. The implemented standard convection oven enables the characterization of glass in different loading modes at temperatures up to 950 °C. Three-point bending, tension and torsional measurements on different glasses, with E and G moduli as a function of frequency and temperature, are presented. Additional tests include superimposing several frequencies in a single temperature sweep (“multiwave”). This type of test results in a considerable reduction of the experiment time and allows to evaluate structural changes of the material and their frequency dependence. Furthermore, DMA in torsion and tension was performed to determine the complex Poisson’s ratio as a function of frequency and temperature within a single test definition. Tests were performed in a frequency range from 0.1 to 10 Hz and temperatures up to the glass transition. While variations in the frequency did not reveal significant changes of the complex Poisson’s ratio of the glass, a monotonic increase of this parameter was observed when increasing the temperature. This contribution outlines the possibilities of DMA in bending, tension and torsion for an extended temperature range. It allows the precise mechanical characterization of material behavior from room temperature up to the glass transition and the softening temperature interval. Compared to other thermo-analytical methods, like Dynamic Scanning Calorimetry (DSC) where mechanical stress is neglected, the frequency-dependence links measurement results (e.g. relaxation times) to real applications

Keywords: dynamic mechanical analysis, oscillatory rheometry, Poisson's ratio, solid glass, viscoelasticity

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Authors: Yingjeng James Li, Yun Jyun Ou, Chih Chi Hsu, Chiao-Chih Hu

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A fuel cell is a device that produces electric power by reacting fuel and oxidant electrochemically. There is no pollution produced from a fuel cell if hydrogen is employed as the fuel. Therefore, a fuel cell is considered as a zero emission device and is a source of green power. A membrane electrode assembly (MEA) is the key component of a fuel cell. It is, therefore, beneficial to develop MEAs with high performance. In this study, an MEA for proton exchange membrane fuel cell (PEMFC) was prepared from a 15-micron thick reinforced PEM. The active area of such MEA is 25 cm2. Carbon supported platinum (Pt/C) was employed as the catalyst for both anode and cathode. The platinum loading is 0.6 mg/cm2 based on the sum of anode and cathode. Commercially available carbon papers coated with a micro porous layer (MPL) serve as gas diffusion layers (GDLs). The original thickness of the GDL is 250 μm. It was compressed down to 163 μm when assembled into the single cell test fixture. Polarization curves were taken by using eight different test conditions. At our standard test condition (cell: 70 °C; anode: pure hydrogen, 100%RH, 1.2 stoic, ambient pressure; cathode: air, 100%RH, 3.0 stoic, ambient pressure), the cell current density is 1250 mA/cm2 at 0.6 V, and 2400 mA/cm2 at 0.4 V. At self-humidified condition and cell temperature of 55 °C, the cell current density is 1050 mA/cm2 at 0.6 V, and 2250 mA/cm2 at 0.4 V. Hydrogen crossover rate of the MEA is 0.0108 mL/min*cm2 according to linear sweep voltammetry experiments. According to the MEA’s Pt loading and the cyclic voltammetry experiments, the Pt electrochemical surface area is 60 m2/g. The ohmic part of the impedance spectroscopy results shows that the membrane resistance is about 60 mΩ*cm2 when the MEA is operated at 0.6 V.

Keywords: fuel cell, membrane electrode assembly, proton exchange membrane, reinforced

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Authors: Przemyslaw Nogly, Tobias Weinert, Daniel James, Sergio Carbajo, Dmitry Ozerov, Antonia Furrer, Dardan Gashi, Veniamin Borin, Petr Skopintsev, Kathrin Jaeger, Karol Nass, Petra Bath, Robert Bosman, Jason Koglin, Matthew Seaberg, Thomas Lane, Demet Kekilli, Steffen Brünle, Tomoyuki Tanaka, Wenting Wu, Christopher Milne, Thomas A. White, Anton Barty, Uwe Weierstall, Valerie Panneels, Eriko Nango, So Iwata, Mark Hunter, Igor Schapiro, Gebhard Schertler, Richard Neutze, Jörg Standfuss

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Ultrafast isomerization of retinal is the primary step in a range of photoresponsive biological functions including vision in humans and ion-transport across bacterial membranes. We studied the sub-picosecond structural dynamics of retinal isomerization in the light-driven proton pump bacteriorhodopsin using an X-ray laser. Twenty snapshots with near-atomic spatial and temporal resolution in the femtosecond regime show how the excited all-trans retinal samples conformational states within the protein binding pocket prior to passing through a highly-twisted geometry and emerging in the 13-cis conformation. The aspartic acid residues and functional water molecules in proximity of the retinal Schiff base respond collectively to formation and decay of the initial excited state and retinal isomerization. These observations reveal how the protein scaffold guides this remarkably efficient photochemical reaction.

Keywords: bacteriorhodopsin, free-electron laser, retinal isomerization mechanism, time-resolved crystallography

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Authors: Joy Winston James, Abdul Kadher Jilani

Abstract:

This review article provides a comprehensive overview of social engineering attacks, specifically those executed through the Kali Linux operating system. It aims to present an in-depth analysis of the background and importance of social engineering in cybersecurity, the tools, and techniques used in these attacks, real-world case studies that demonstrate their effectiveness, and ethical considerations that need to be taken into account while using them. The article highlights the Kali Linux tools that are commonly used in social engineering attacks, including SET, Metasploit, and BeEF, and discusses techniques such as phishing, pretexting, and baiting that are crucial in conducting successful social engineering attacks. It further explores real-world case studies that demonstrate the effectiveness of these techniques, emphasizing the importance of implementing effective countermeasures to reduce the risk of successful social engineering attacks. Moreover, the article sheds light on ethical considerations that need to be taken into account while using social engineering tools, emphasizing the importance of using them ethically and legally. Finally, the article provides potential countermeasures such as two-factor authentication, strong password policies, and regular security audits to help individuals and organizations better protect themselves against this growing threat. By understanding the tools and techniques used in social engineering attacks and implementing appropriate countermeasures, individuals and organizations can minimize the risk of successful social engineering attacks and improve their cybersecurity posture. To illustrate the effectiveness of social engineering attacks, we present real-world case studies that demonstrate how easily individuals and organizations can fall prey to these attacks. We also discuss ethical considerations that must be taken into account while using social engineering tools, emphasizing the need for responsible and legal use of these tools.

Keywords: pen testing, hacking, Kali Linux, social engineering

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Authors: E. Akdur Öztürk, F. İrvasa Bilgiç, A. Ludovisi , O. Gülbahar, D. Dirim Erdoğan, M. Korkmaz, M. Á. Gómez Morales

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Anisakidosis is a zoonotic human fish-borne parasitic disease caused by accidental ingestion of anisakid third-stage larvae (L3) of members of the Anisakidae family present in infected marine fish or cephalopods. Infection with anisakid larvae can lead to gastric, intestinal, extra-gastrointestinal and gastroallergic forms of the disease. Anisakid parasites have been reported in almost all seas, particularly in the Mediterranean Sea. There is a remarkably high level of risk exposure to these zoonotic parasites as they are present in economically and ecologically important fish of Europe. Anisakid L3 larvae have been also detected in several fish species from the Aegean Sea. Turkey is a peninsular country surrounded by Black, Aegean and the Mediterranean Sea. In this country, fishing habit and fishery product consumption are highly common. In recent years, there was also an increase in the consumption of raw fish due to the increasing interest in the cuisine of the Far East countries. In different regions of Turkey, A. simplex (inMerluccius Merluccius Scomber japonicus, Trachurus mediterraneus, Sardina pilchardus, Engraulis encrasicolus, etc.), Anisakis spp., Contraceucum spp., Pseudoterronova spp. and, C. aduncum were identified as well. Although it is accepted both the presence of anisakid parasites in fish and fishery products in Turkey and the presence of Turkish people with allergic manifestations after fish consumption, there are no reports of human anisakiasis in this country. Given the high prevalence of anisakid parasites in the country, the absence of reports is likely not due to the absence of clinical cases rather to the unavailability of diagnostic tools and the low awareness of the presence of this infection. The aim of the study was to set up an IgE-Western Blot (WB) based test to detect the anisakidosis sensitization among Turkish people with a history of allergic manifestation related to fish consumption. To this end, crude worm antigens (CWA) and allergen enriched fraction (50-66% ) were prepared from L3 of A. simplex (s.l.) collected from Lepidopus caudatus fished in the Mediterranean Sea. These proteins were electrophoretically separated and transferred into the nitrocellulose membranes. By WB, specific proteins recognized by positive control serum samples from sensitized patients were visualized on nitrocellulose membranes by a colorimetric reaction. The CWA and 50–66% fraction showed specific bands, mainly due to Ani s 1 (20-22 kD) and Ani s 4 (9-10 kD). So far, a total of 7 serum samples from people with allergic manifestation and positive skin prick test (SPT) after fish consumption, have been tested and all of them resulted negative by WB, indicating the lack of sensitization to anisakids. This preliminary study allowed to set up a specific test and evidence the lack of correlation between both tests, SPT and WB. However, the sample size should be increased to estimate the anisakidosis burden in Turkish people.

Keywords: anisakidosis, fish parasite, serodiagnosis, Turkey

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