bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of a commercial ELISA kit for detection of antibodies against Toxoplasma gondii in serum, plasma and meat juice from experimentally and naturally infected sheep
Authors: Glor Sabine B , Edelhofer Renate , Grimm Felix , Deplazes Peter , Basso Walter 
Published: April 2013

Abstract

Background
Toxoplasmosis is one of the most common food borne zoonoses worldwide, and can be a serious life-threatening disease in the congenitally infected fetus and in immunosupressed patients. Among food animals, sheep along with goats and pigs possess the highest incidence of T. gondii cysts in meat, and play a major role as a source of human infection.

Methods
In this study, a new commercial ELISA kit (PrioCHECK® Toxoplasma Ab SR, Prionics Schlieren-Zurich, Switzerland) for the detection of anti-T. gondii antibodies in serum, plasma and meat juice of sheep, was evaluated by comparing it with the indirect fluorescent antibody test (IFAT), indirect haemagglutination test (IHA) and real-time PCR, on samples from experimentally inoculated and naturally exposed sheep.

Results
The commercial ELISA detected the infection status in 50% and 100% of sheep orally inoculated with 10,000 T. gondii oocysts (n = 6), from two or three weeks post infection (wpi), respectively, both on serum and plasma samples. Meat juice from all experimentally inoculated sheep collected at slaughter (12 wpi) showed positive ELISA values. In naturally exposed sheep (n = 396), the ELISA showed a very good agreement with IFAT (kappa = 0.91-1.0) and IHA (kappa = 0.96-1.0) performed on serum; and a positive correlation was observed between ELISA values and IFAT titers. By a Receiver Operating Characteristics (ROC) curve analysis, the commercial ELISA had relative sensitivities between 93.33% and 100%, and relative specificities between 96.87% and 100% respect to IFAT and IHA, depending on the considered cut-off value and animal groups tested. Furthermore, the ELISA correctly recognized all animals reacting positive in real-time PCR. The ELISA results on meat juice agreed with those on serum samples in all experimentally inoculated animals, and in 94 out of 96 (97.9%) naturally exposed sheep, when meat juice was tested at a 1:10 dilution.

Conclusion
The commercial ELISA kit evaluated in this study could represent a valuable tool to improve the surveillance and reporting system for T. gondii in sheep populations at the farm level or for diagnosis at the slaughterhouse, contributing to the control of this widespread zoonosis.
Generation of a luciferase-based reporter for CHH and CG DNA methylation inArabidopsis thaliana
Authors: Dinh Thanh Theresa , O’Leary Michael , Won So Youn , Li Shengben , Arroyo Lorena , Liu Xigang , Defries Andrew , Zheng Binglian , Cutler Sean R , Chen Xuemei 
Published: April 2013

AbstractBackgroundDNA methylation ensures genome integrity and regulates gene expression indiverse eukaryotes. InArabidopsis, methylation occurs in threesequence contexts: CG, CHG and CHH. The initial establishment of DNAmethylation at all three sequence contexts occurs through a process known asRNA-directed DNA methylation (RdDM), in which small RNAs bound by Argonaute4(AGO4) guide DNA methylation at homologous loci through thede novomethyltransferase DRM2. Once established, DNA methylation at each of thethree sequence contexts is maintained through different mechanisms. Althoughsome players involved in RdDM and maintenance methylation have beenidentified, the underlying molecular mechanisms are not fully understood. Toaid the comprehensive identification of players in DNA methylation, wegenerated a transgenic reporter system that permits genetic and chemicalgenetic screens inArabidopsis.ResultsA dual35Spromoter (d35S) driven luciferase (LUC)reporter was introduced intoArabidopsisandLUCL, a linewith a low basal level of luciferase activity, was obtained.LUCLwas found to be a multi-copy, single-insertion transgene that containsmethylated cytosines in CG, CHG and CHH contexts, with the highestmethylation in the CG context. Methylation was present throughout thepromoter andLUCcoding region. Treatment with an inhibitor ofcytosine methylation de-repressed luciferase activity. A mutation inMET1, which encodes the CG maintenance methyltransferase,drastically reduced CG methylation and de-repressedLUCexpression.Mutations inAGO4andDRM2also de-repressedLUCexpression, albeit to a smaller extent than loss ofMET1. UsingLUCLas a reporter line, we performed a chemical screen forcompounds that de-repressLUCexpression, and identified achemical, methotrexate, known to be involved in biogenesis of the methyldonor.ConclusionWe developed a luciferase-based reporter system,LUCL, which reportsboth RdDM and CG maintenance methylation inArabidopsis. The lowbasal level ofLUCLexpression provides an easy readout in geneticand chemical genetic screens that will dissect the mechanisms of RdDM andmethylation maintenance.
Blood transfusion in deceased donor kidney transplantation
Authors: Marzouk Karim , Lawen Joseph , Kiberd Bryce A 
Published: April 2013

Abstract

Background
Given the unpredictable timing of deceased donor organs and the need for blood transfusion, this study was carried out to determine the rate and risk factors for transfusion in order to identifying a low-risk cohort in the face of a critical blood shortage.

Methods
This retrospective chart review examined 306 consecutive deceased solitary kidney transplant recipients from January 2006 to August 2012.

Results
Records show that 80 (26.1%) patients were transfused with a total of 300 units (0.98 units/transplant) during their first hospital stay. Transfusions were higher in patients on warfarin (8/14, 57%, 5.1 units/transplant) and antiplatelet agents (46/136, 33.8%, 1.1 unit/transplant) compared to no anticoagulants (74/156, 16.7%, 0.47 units/transplant). In a multivariable logistic regression analysis warfarin (odd ratio (OR) 8.2, 95% confidence interval (CI) 2.5–27, P=0.001), antiplatelet agents (OR 2.9, 95% CI 1.6–5.3, P=0.001), recipient age ≥55 years (OR 2.2, 95% CI 1.2–3.9, P=0.008), recipient male (OR 0.36, 95% CI 0.2–0.64, P=0.001) and preop hemoglobin ≥115 g/L (OR 0.32, 95% CI 0.18–0.57, P<0.001) were independent predictors of blood transfusion. Lower bleeding cohorts with transfusion rates <5% could not be identified.

Conclusion
The need for blood is significantly higher in subjects on either warfarin or antiplatelet agents. These patients might be avoided if kidney transplantation is to occur during a critical blood shortage. Unfortunately even patients not on anticoagulation are at some risk.
Comparison of antioxidant activity and flavanol content of cacao beans processed by modern and traditional Mesoamerican methods
Authors: Chin Elizabeth , Miller Kenneth B , Payne Mark J , Hurst W Jeffery , Stuart David A 
Published: April 2013

Abstract
The use of cacao, in its familiar food and beverage form, dates back about 3,800 years. By the time of the discovery of America by Europeans, the Aztecs and Mayans had developed methods for drying, roasting and grinding cacao beans for use in beverages and foods. Today, the same processes are used, but have been adapted to modern machinery. The current study was conducted to compare the traditional Mesoamerican processing and modern processing methods and their impact on the antioxidant activity and flavan-3-ol content of the resulting processed cocoa mass. Two cocoa bean types were used: unfermented cocoa beans commonly produced and consumed today by the native peoples of Mesoamerica, and fermented Ivory Coast cocoa beans representing the most common country of origin for cocoa in the world today. Both bean types were processed by roasting and grinding using traditional and modern processing methods. The traditional method consisted of roasting whole beans on an earthenware comal heated with wood charcoal, de-shelling the beans, then grinding the beans to a paste using a stone metate and mano. The modern method consisted of roasting cocoa beans with pilot-scale equipment that simulates large-scale chocolate manufacturing using whole bean drum roasters, deshelling the beans followed by mechanical grinding using a ball mill producing a chocolate paste. The antioxidant capacity and flavanol content of these chocolate pastes were then determined. The data show that the antioxidant capacity and flavanol content of unprocessed Mexican Lavado cocoa beans were significantly higher than that of the unprocessed, fermented Ivory Coast cocoa beans. In unfermented Mexican Lavado cocoa beans, the traditional and modern processing revealed no clear advantage with respect to the antioxidant and flavanol contents. However, for fermented Ivory Coast beans, there were some differences in the level of flavanols between traditionally processed and modern processed fermented beans. These differences, while significant for some, but not all of the flavanol measures, were attributed to final roast temperatures achieved and to the possible lack of uniformity of bean fermentation.
Effect of Melia azedarach (Sapindales: Meliaceae) fruit extracts on Citrus Leafminer Phyllocnistis citrella (Lepidoptera: Gracillariidae)
Authors: Mckenna Maher M , Abou-Fakhr Hammad Efat M , Farran Mohamad T 
Published: April 2013

Abstract

Melia azedarach L. extracts were studied in comparison with selected biorational insecticides against the citrus leafminer Phyllocnistis citrella Stainton under field conditions. Citrus limon (L.) Burm. F. trees were exposed to: Melia extracts of green and mature fruits, Neem oil (30% a.i.), abamectin (1.8% a.i.) and control. Two sprays of each treatment (except for Melia mature fruit extract) were executed at 10-d intervals. The live number of the 1st and later (2nd & 3rd) larval instars per leaf were recorded at initial sampling date and at 10-d intervals after each spray application. Results indicated that there were significant differences in the number of live larval instars among treatments. Melia extracts and the two biorationals, neem oil and abamectin, decreased the larvae population significantly to lower numbers than that of the control at 10 days after each spray application. However, the decrease caused by neem oil and abamectin was significantly higher than that of Melia extracts. Thus, these extracts might be considered as potential alternative with other biorational control methods in management of the leafminer. Further research including bioassays is needed to determine the factors responsible for reducing larvae population and whether these Melia extracts can be utilized in future citrus IPM programs as a tool for citrus leafminer management.
Washback of IELTS on the Assumption College English Program
Authors: Sanonguthai suchada 
Published: April 2013

Abstract
This paper reports and discusses how the IELTS test has brought its impact to Assumption College Thonburi English Program (ACTEP)'s exit testing, English courses offered and foreign teachers' teaching. Two different methods of data collection apply; an interview with the ACTEP Academic Head and questionnaire for Grades 10-11 students and foreign teachers. It has been found that in order to assure Grade 12 performance on the IELTS test, other well-known achievement tests have been put into the ACTEP academic policy. IELTS preparatory courses have been listed into the Grades 10- 12 ACTEP curriculum. The findings show that the foreign teachers, both Native-English speakers and Non-Native English speakers teaching staff in the ACTEP, need more insights to the IELTS test format. It is also well worth recommending that students need to practice more during their high school years as their Grade 11exit test, the CU-TEP test, cannot reflect all strategies needed in the IELTS test.
An Examination of the No Fail Policy in Thailand and the Effect on Community Relations
Authors: Halligan Kristin M 
Published: April 2013

Abstract
No fail or social promotion policies have been implemented in many countries around the world over the last sixty years. Are these policies harmful or helpful in regard to academic achievement and well being of students? This article examines the trends of social promotion policy in the United States and Thailand. Research has been conducted at Assumption College Primary Section. Interviews and questionnaires were conducted and analyzed in order to observe opinions of educators, parents and teachers in regard to these policies.
Students' Perceptions of Computerized TOEFL Test
Authors: Noubandegani Parvane Azadi 
Published: April 2013

Abstract
The present study investigated students' perception of computerized TOEFL test. Subject of this study were 100 adult male and female students who took the iBT TOEFL test in Iran. Participants were provided with a researcher-developed questionnaire on the advantages and disadvantages of Computer-Based Test (CBT) compared to Paper- Based Test (PBT). The collected data were analyzed using descriptive statistics and factor analysis to investigate the perceptions of the students. Results of this study showed that students perceived the disadvantages of CBT were more than its advantages.
Students' Perceptions of the Impact of the College English Test
Authors: Li Hongli , Zhong Qi , Suen Hoi K 
Published: April 2013

Abstract
Designed to assess college students' English ability, the College English Test (CET) is regarded as the most influential English test in China. This study investigates students' perceptions of the impact of the CET on their English-learning practices and their affective conditions. A survey was administered to 150 undergraduate students at a university in Beijing. It was found that students perceived the impact of the CET to be pervasive. In particular, the majority of the respondents indicated that the CET had a greater impact on what they studied than on how they studied. Most of the students surveyed felt the CET had motivated them to make a greater effort to learn English. Many students seemed to be willing to put more effort on the language skills most heavily weighted in the CET. About half of the students reported a higher level of self-efficacy in regard to their overall English ability and some specific English skills as a result of taking or preparing for the CET. However, many students also reported experiencing increased pressure and anxiety in relation to learning English. This study provides important evidence about how the CET influences college students' English learning in China, and directions for further research are also suggested.
Washback Effects of the New English Assessment System on Secondary Schools in Bhutan
Authors: Kirkpatrick Robert , Gyem Kinley 
Published: April 2013

Abstract
In 2006, Bhutan changed the secondary school curriculum. This study examines the washback effect of the English assessment system associated with this new curriculum. Based on questionnaire responses from 56 EFL secondary school teachers in Bhutan, the study suggests the new curriculum produces both positive and also negative washback. In order for the new curriculum's benefit to outweigh any harm it may cause, teachers should receive proper guidance and support during this transition.
Association Between Abdominal Obesity and Fracture Risk: A Prospective Study
Authors: Yang Shuman , Nguyen Nguyen D. , Center Jacqueline R. , Eisman John A. , Nguyen Tuan V. 
Published: April 2013

Context:
Higher body weight is associated with greater bone mineral density (BMD) and lower fracture risk. However, the relationship between abdominal fat mass (aFM) and fracture risk is unclear because of limited prospective data. The present study sought to examine the association between aFM, BMD, and fracture risk.

Methods:
The study was designed as a prospective investigation, in which a sample of 1126 participants (360 men and 766 women) aged 50 years or older had been continuously followed up for an average of 5 years. The mean age of participants was 71 years (range, 57–94 years). At baseline, BMD at the femoral neck and lumbar spine and aFM were measured by dual-energy X-ray absorptiometry. The incidence of low-trauma and nonpathological fractures was ascertained prospectively from X-ray reports.

Results:
During the follow-up period, 19 men and 107 women had sustained a fracture. In women, each 1-kg lower aFM was associated with a 50% higher risk of fracture (hazard ratio [HR], 1.50; 95% confidence interval [CI], 1.10–2.05) after adjustment for age, femoral neck BMD, falls, stature, physical activity, and prior fracture. Subgroup analysis by fracture type found that the association was mainly observed in clinical vertebral fracture (HR, 1.96; 95% CI, 1.22–3.13). In men, although there was no statistically significant association between aFM and fracture risk (HR, 1.15; 95% CI, 0.58–2.25), the strength of this finding is affected negatively by the low number of fractures.

Conclusions:
Lower abdominal fat was significantly associated with an higher fracture risk in women.
Norepinephrine transporter variant A457P knock-in mice display key features of human postural orthostatic tachycardia syndrome
Authors: Shirey-Rice Jana K. , Klar Rebecca , Fentress Hugh M. , Redmon Sarah N. , Sabb Tiffany R. , Krueger Jessica J. , Wallace Nathan M. , Appalsamy Martin , Finney Charlene , Lonce Suzanna , Diedrich André , Hahn Maureen K. 
Published: April 2013

Summary
Postural orthostatic tachycardia syndrome (POTS) is a common autonomic disorder of largely unknown etiology that presents with sustained tachycardia on standing, syncope and elevated norepinephrine spillover. Some individuals with POTS experience anxiety, depression and cognitive dysfunction. Previously, we identified a mutation, A457P, in the norepinephrine (NE; also known as noradrenaline) transporter (NET; encoded by SLC6A2) in POTS patients. NET is expressed at presynaptic sites in NE neurons and plays a crucial role in regulating NE signaling and homeostasis through NE reuptake into noradrenergic nerve terminals. Our in vitro studies demonstrate that A457P reduces both NET surface trafficking and NE transport and exerts a dominant-negative impact on wild-type NET proteins. Here we report the generation and characterization of NET A457P mice, demonstrating the ability of A457P to drive the POTS phenotype and behaviors that are consistent with reported comorbidities. Mice carrying one A457P allele (NET+/P) exhibited reduced brain and sympathetic NE transport levels compared with wild-type (NET+/+) mice, whereas transport activity in mice carrying two A457P alleles (NETP/P) was nearly abolished. NET+/P and NETP/P mice exhibited elevations in plasma and urine NE levels, reduced dihydroxyphenylglycine (DHPG), and reduced DHPG:NE ratios, consistent with a decrease in sympathetic nerve terminal NE reuptake. Radiotelemetry in unanesthetized mice revealed tachycardia in NET+/P mice without a change in blood pressure or baroreceptor sensitivity, consistent with studies of human NET A457P carriers. NET+/P mice also demonstrated behavioral changes consistent with CNS NET dysfunction. Our findings support that NET dysfunction is sufficient to produce a POTS phenotype and introduces the first genetic model suitable for more detailed mechanistic studies of the disorder and its comorbidities.
Infrastructure Planning for Electric Vehicles with Battery Swapping
Authors: Mak Ho-Yin , Rong Ying , Shen Zuo-Jun Max 
Published: April 2013

Electric vehicles (EVs) have been proposed as a key technology to help cut down the massive greenhouse gas emissions from the transportation sector. Unfortunately, because of the limited capacity of batteries, typical EVs can only travel for about 100 miles on a single charge and require hours to be recharged. The industry has proposed a novel solution centered around the use of “swapping stations,” at which depleted batteries can be exchanged for recharged ones in the middle of long trips. The possible success of this solution hinges on the ability of the charging service provider to deploy a cost-effective infrastructure network, given only limited information regarding adoption rates. We develop robust optimization models that aid the planning process for deploying battery-swapping infrastructure. Using these models, we study the potential impacts of battery standardization and technology advancements on the optimal infrastructure deployment strategy. This paper was accepted by Dimitris Bertsimas, optimization.
How Do Firm Financial Conditions Affect Product Quality and Pricing?
Authors: Phillips Gordon , Sertsios Giorgo 
Published: April 2013

We analyze the interaction of firm product quality and pricing decisions with financial distress and bankruptcy in the airline industry. We consider an airline's choices of quality and price as dynamic decisions that trade off current cash flows for future revenue. We examine how airline mishandled baggage, on-time performance, and pricing are related to financial distress and bankruptcy, controlling for the endogeneity of financial distress and bankruptcy. We find that an airline's quality decisions are differentially affected by financial distress and bankruptcy. Product quality decreases when airlines are in financial distress, consistent with financial distress reducing a firm's incentive to invest in quality. In contrast, in bankruptcy product quality increases relative to financial distress. In addition, we find that firms price more aggressively when in financial distress consistent with firms trying to increase short-term market share and revenues. This paper was accepted by Wei Jiang, finance.
Unpacking the Future: A Nudge Toward Wider Subjective Confidence Intervals
Authors: Jain Kriti , Mukherjee Kanchan , Bearden J. Neil , Gaba Anil 
Published: April 2013

Subjective probabilistic judgments in forecasting are inevitable in many real-life domains. A common way to obtain such judgments is to assess fractiles or confidence intervals. However, these judgments tend to be systematically overconfident. Further, it has proved particularly difficult to debias such forecasts and improve the calibration. This paper proposes a simple process that systematically leads to wider confidence intervals, thus reducing overconfidence. With a series of experiments, including with professionals, we show that unpacking the distal future into intermediate more proximal futures systematically improves calibration. We refer to this phenomenon as the time unpacking effect, find it is robust to different elicitation formats, and address the possible reasons behind it. We further show that this results in better overall forecasting performance when improved calibration is traded off against less sharpness, and that substantive benefits can be obtained even from just one level of time unpacking. This paper was accepted by Teck Ho, decision analysis.
Price-Quoting Strategies of an Upstream Supplier
Authors: Hu Bin , Beil Damian R. , Duenyas Izak 
Published: April 2013

This paper studies an upstream supplier who quotes prices for a key component to multiple sellers that compete for an end-buyer's indivisible contract. At most one of the supplier's quotes may result in downstream contracting and hence produce revenue for her. We characterize the supplier's optimal price-quoting strategies and show that she will use one of two possible types of strategies, with her choice depending on the sellers' profit potentials relative to their uncertainties: secure, whereby she will always have business; or risky, whereby she may not have business. Addressing potential fairness concerns, we also study price-quoting strategies in which all sellers receive equal quotes. Finally, we show that the supplier's optimal mechanism resembles auctioning a single quote among the sellers. This paper can assist upstream suppliers in their pricing decisions and provides general insights into multitier supply chains' pricing dynamics. This paper was accepted by Martin Lariviere, operations management.