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• We compared the performance of the STANDARD F and SD BIOLINE stool antigen tests. • The STANDARD F and SD BIOLINE assays showed comparable sensitivity and specificity. • The STANDARD F assay is useful for detection of Helicobacter pylori infection. We compared the performance of the STANDARD F and SD BIOLINE stool antigen tests in 335 patients. The performance of STANDARD F (sensitivity: 95.6%; specificity: 94%) was highly comparable to that of SD BIOLINE (sensitivity: 92.6%; specificity: 93.5%), suggesting that STANDARD F is useful for the detection of Helicobacter pylori infection. [ABSTRACT FROM AUTHOR]

Highlights • A comprehensive commissioning protocol is designed to assess the MRI performance of integrated MR-linac systems. • The imaging performance of four recently installed 1.5T MR-linac systems is assessed in a multi-institutional study. • A benchmark data set is provided by making the results as well as the corresponding measurement protocols publically available. Abstract Background Magnetic Resonance linear accelerator (MR-linac) systems represent a new type of technology that allows for online MR-guidance for high precision radiotherapy (RT). Currently, the first MR-linac installations are being introduced clinically. Since the imaging performance of these integrated MR-linac systems is critical for their application, a thorough commissioning of the MRI performance is essential. However, guidelines on the commissioning of MR-guided RT systems are not yet defined and data on the performance of MR-linacs are not yet available. Materials & methods Here we describe a comprehensive commissioning protocol, which contains standard MRI performance measurements as well as dedicated hybrid tests that specifically assess the interactions between the Linac and the MRI system. The commissioning results of four MR-linac systems are presented in a multi-center study. Results Although the four systems showed similar performance in all the standard MRI performance tests, some differences were observed relating to the hybrid character of the systems. Field homogeneity measurements identified differences in the gantry shim configuration, which was later confirmed by the vendor. Conclusion Our results highlight the importance of dedicated hybrid commissioning tests and the ability to compare the machines between institutes at this very early stage of clinical introduction. Until formal guidelines and tolerances are defined the tests described in this study may be used as a practical guideline. Moreover, the multi-center results provide initial bench mark data for future MR-linac installations. [ABSTRACT FROM AUTHOR]

Porous media play an important role in the process of storage energy. In this paper, the influence of porous media on the performance of a double pass hybrid PV/thermal air collector was achieved by building an experimental set-up for this purpose. The study showed that using porous media expanded the area of heat transfer and thus increased the thermal efficiency and temperature of the exit air from the hybrid solar collector. The compound efficiency was increased (3%) after using the porous medium in the lower ducts of the double-pass hybrid collector. At the same time, the pressure drop was increased after using the porous media. In this analysis, it was concluded that the hybrid solar collector with porous media and glass cover is more thermally efficient than the other design form. The results showed a rise in the electrical efficiency with the increase of the fluid flow rate. This increase in the value of the electrical efficiency was due to the higher volumetric air flow which enhanced the PV panel cooling. Also, the results displayed that fixing a glass layer on the hybrid collector caused the rise in thermal efficiency and reduction in the electrical efficiency of the hybrid collector. The highest value for the daily thermal efficiency was 80.23% in the collector that used porous media and glass cover, while the higher value for the thermal efficiency was 51.25% without porous media and glass cover. Also, the highest value for the daily electrical efficiency was 8.7% in the collector that used porous media and the higher value for the daily electrical efficiency was 10.91% without porous media and without glass cover. The use of porous media and glass cover in the hybrid system is a desirable option when using the hybrid system for electrical generation only. [ABSTRACT FROM AUTHOR]

Ergonomics interventions have the potential to improve operational performance and employee well-being. We introduce a framework for ergonomics climate , the extent to which an organization emphasizes and supports the design and modification of work to maximize both performance and well-being outcomes. We assessed ergonomics climate at a large manufacturing facility twice during a two-year period. When the organization used ergonomics to promote performance and well-being equally, and at a high level, employees reported less work-related pain. A larger discrepancy between measures of operational performance and employee well-being was associated with increased reports of work-related pain. The direction of this discrepancy was not significantly related to work-related pain, such that it didn't matter which facet was valued more. The Ergonomics Climate Assessment can provide companies with a baseline assessment of the overall value placed on ergonomics and help prioritize areas for improving operational performance and employee well-being. [ABSTRACT FROM AUTHOR]

• Observation of spray of biodiesel is done to correlate with engine performance. • Mass of fuel molecules of B100 are found to be heavier than B0 and B50. • Mass of fuel molecules of B50 and B0 are found to be similar. • Satuer mean diameters of fuel molecules of B50 and B100 are larger than diesel. • Penetration lengths of vapour of B50 and B100 are 6.28% and 13.75% longer. • Combustion duration B0, B50 and B100 are 52°CA, 57°CA and 59°CA, respectively. Palm oil diesel (POD) is derived from palm oil using an esterification process. POD has similar physicochemical properties to fossil diesel, and this allows POD to be the primary substitute to diesel. However, existing research has found that the combustion of POD in CI engines produce lower performance standards than pure diesel. This is due to POD having a higher viscosity, density and presence of heavier molecules resulting in poor evaporation and mixing with the air leading to higher brake specific fuel consumption (BSFC) and reduced power. This research aims to observe the fuel spray behaviors inside the combustion chamber and corelate these with the lower performance of POD than diesel. POD is tested at 100% (B100) and, blended with diesel at a ratio of 50/50 (B50) by volume to reduce the viscosity. The study of spray properties in real engines is expensive and difficult, with most studies being performed in constant volume transparent chambers using Mie-scattering and Schlieren imaging techniques. Therefore, the engine simulation is conducted using ANSYS Forte software to observe the in-cylinder spray behaviors. A 26-kW diesel engine used in a generator is modelled using SolidWorks with respective performance parameters noted from simulation data. The CHEMKIN-PRO software is used to create POD by solving thousands of reaction combinations. Spray analysis of fuels shows longer penetration lengths with POD, higher Sauter Mean Diameter (SMD) and heavier mass of fuel molecules than diesel. These along with a lower calorific value of POD resulted in lower power and a higher brake specific fuel consumption than diesel. Furthermore, B50 performs better than B100. [ABSTRACT FROM AUTHOR]

Abstract: This article provides a synthesis of the international evidence with respect to the impact of privatization on the efficiency and performance of airports and seaports. The theoretical frameworks, particularly the arguments for potential efficiency gains from privatization are reviewed first, followed by a discussion and evaluation of the empirical results and conclusions from selected studies of airport and seaport privatization. Then, policy implications of the theoretical frameworks and the international evidence are discussed with special reference to privatization of the transport infrastructure in developing countries. Future research directions are also suggested. [Copyright &y& Elsevier]

Abstract: Objective: To explore the role of a four-item Global Rating Scale (GRS) that could be used in place of the Appraisal of Guidelines, Research and Evaluation II (AGREE II). Study Design and Setting: A mixed four-factor design was used (User Type, Evaluation Type, Clinical Topic, Guideline). Participants were asked to read and evaluate a guideline using both the AGREE II draft and GRS or GRS only and to complete a series of questions regarding overall guideline quality, adoption, utility, and acceptability. Results: One GRS item varied as a function of User Type. Each item was a significant predictor of participants'' outcome measures. All items were rated as useful by stakeholders. The GRS rating scores, outcome measures, and usefulness scores did not vary between the two Evaluation Type conditions. Correlations between the GRS and the outcome measures were stronger compared with those between the AGREE II draft and these measures. Conclusion: Although the GRS is less sensitive than the AGREE II in detecting differences in guideline quality as a function of User Type, its items did predict important outcome measures related to guideline adoption. The GRS may play a role in guideline evaluation, although further study is warranted. [Copyright &y& Elsevier]

Abstract: It is well known that neighbor discovery is a critical component of proactive routing protocols in wireless ad hoc networks. However there is no formal study on the performance of proposed neighbor discovery mechanisms. This paper provides a detailed model of key performance metrics of neighbor discovery algorithms, such as node degree and the distribution of the distance to symmetric neighbors. The model accounts for the dynamics of neighbor discovery as well as node density, mobility, radio and interference. The paper demonstrates a method for applying these models to the evaluation of global network metrics. In particular, it describes a model of network connectivity. Validation of the models shows that the degree estimate agrees, within 5% error, with simulations for the considered scenarios. The work presented in this paper serves as a basis for the performance evaluation of remaining performance metrics of routing protocols, vital for large scale deployment of ad hoc networks. [Copyright &y& Elsevier]

Abstract: Manganese (Mn) is an essential nutrient element in citrus growing and Mn deficiency causes some problems related with physiological and morphological structure. Spatial evaluation of Mn obtained from soils in citrus-growing areas is the main objective of this paper. For this purpose, a citrus-growing region in Turkey has been selected and three effective estimation methods: kriging, neural–fuzzy modelling, and fuzzy interval arithmetic have been considered for the spatial evaluations. The model works primarily focus on the model accuracy and smoothing degree of estimations. In addition, error analysis and comparative assessments, which present the advantages and drawbacks of the models, are conducted in the paper. The results and performance evaluations prove the superiorities of soft computing approach in this evaluation. [Copyright &y& Elsevier]

Abstract: Study Objective: To study the perceptions of anesthesiology resident program directors about the value of the Medical Student Performance Evaluation (MSPE) in predicting successful residents. Design: Survey instrument. Setting: Anesthesiology department of a university hospital. Measurements: An online survey was sent to 115 U.S. medical school-based anesthesiology residency program directors. Descriptive statistics were used to report which sections of the MSPE were predictive and which were not predictive. More than 30 qualitative comments were hand-coded for frequency and emerging themes. Main Results: Those sections predictive of success included the (a) academic history summary, (b) academic progress, (c) academic ranking, and (d) the candidate''s comparative clinical performance. Non-predictive sections included (a) unique characteristics, (b) pre-clinical comparative performance, (c) professional behaviors versus those of classmates, (d) summary statement, and (e) Appendix E. The strongest theme emerging from the qualitative findings was a desire for the MSPE to indicate candidates'' rank. Conclusions: Anesthesiology programs tend to rely on the most objective sections of the MSPE. While program directors valued comments from clinical faculty, they did not hold the preclinical performance relative to peers in similar esteem, and there is a lack of reliability in the MSPE''s assessment of professional behaviors. [Copyright &y& Elsevier]

Abstract: The purpose of benchmarking is to settle improvement processes by comparing the activities to quality standards. The proposed methodology is illustrated by benchmark business cases performed inside medical plants on some items like nosocomial diseases or organization of surgery facilities. Moreover, the authors have built a specific graphic tool, enhanced with balance score numbers and mappings, so that the comparison between different anesthesia–reanimation services, which are willing to start an improvement program, is easy and relevant. This ready-made application is even more accurate as far as detailed tariffs of activities are implemented. [Copyright &y& Elsevier]

Abstract: The aim of this study was to assess the predisposing factors leading to uterine infection in dairy cows and evaluate its impact on the cow''s performance. Performance indicators included feed intake, milk fat and protein composition, milk yield, fertility and culling. Data were studied from 2914 completed lactations from the Holstein Friesian Langhill Dairy herd between January 1990 and August 2005. There were 402 cases of uterine infection (from 321 cows) in the Langhill herd, a level of 13.8% during the study period. Calving assistance was highly associated with the incidence of uterine infection (χ 2 =106.63, P <0.001). Failure to conceive (χ 2 =3.89, P <0.05; χ 2 =11.20, P <0.001) and culling (χ 2 =13.66, P <0.001, χ 2 =8.55, P <0.01) were also implicated with calving assistance and uterine infection, respectively. The main predisposing factors related to an incidence of uterine infection were calving assistance, twin births, malpresented calves, and retained placenta. First-time calvers and cows with a shorter gestation length were associated with more cases of uterine infections. Additionally, lower daily dry matter intakes and milk yields during the first 100 days in milk (DIM) were associated with higher incidence levels of uterine infection. Also, a higher incidence level of uterine infection was related to lower milk protein composition from 1 to 21 DIM and a poorer body condition from 101 to 300 DIM. Cows with poorer drying off body condition scores and longer lactation lengths were associated with a higher incidence level of uterine infection. Calving assistance was associated with male and twin births, first-time calvers and cows with oversized calves. Cows with an assisted calving were also associated with an increased number of days from calving to first service. The predisposing factors influencing the occurrence of calving assistance can be influenced by suitable management to reduce the chances of oversized calves, the detrimental effects of twin births (such as calving assistance and retained placentas) and prenatal knowledge of the calf''s sex. The occurrence of uterine infection can be reduced by minimising the need for assistance at calving. Assistance should only be carried out when necessary and appropriate hygiene should be used to decrease the incidence of uterine infections from intervention and involuntary culling due to cows failing to conceive. [Copyright &y& Elsevier]

Abstract: The number of researchers studying perceptual-cognitive expertise in sport is increasing. The intention in this paper is to review the currently accepted framework for studying expert performance and to consider implications for undertaking research work in the area of perceptual-cognitive expertise in sport. The expert performance approach presents a descriptive and inductive approach for the systematic study of expert performance. The nature of expert performance is initially captured in the laboratory using representative tasks that identify reliably superior performance. Process-tracing measures are employed to determine the mechanisms that mediate expert performance on the task. Finally, the specific types of activities that lead to the acquisition and development of these mediating mechanisms are identified. General principles and mechanisms may be discovered and then validated by more traditional experimental designs. The relevance of this approach to the study of perceptual-cognitive expertise in sport is discussed and suggestions for future work highlighted. [Copyright &y& Elsevier]