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Abstract Flow boiling instabilities inherent in microchannels / microgaps remain to be a serious issue in two-phase high-heat-flux cooling applications, as they cause significant oscillations in flow rate, temperature, pressure, reduction in heat transfer coefficient (HTC), and eventually early occurrence of critical heat flux (CHF). This study experimentally investigated the effects of various configurations of inlet restrictors (IRs) on the thermal hydraulic performance of flow boiling in a microchannel heat sink, which has a single rectangular microchannel with an aspect ratio of 13.12 and a hydraulic diameter of the 708 µm. The experiments were carried out for the microchannel with three designs of inlet restrictors: one-slot opening (1IR), three-slot openings (3IR), and five-slot openings (5IR), for mass fluxes of 32.68, 81.29 and 144 kg/m2 s, respectively. The effects of the various IRs on the CHF, average HTC and pressure drops of the microchannel heat sink were analyzed. The results showed that all test cases with IRs improved the CHF performance of the flow boiling microchannel heat sink, where the 5IR case works best at low mass flux and the 1IR case works best at high mass flux. The results also illustrated that the IRs reduce the HTC at low mass flux, but improve the HTC at high mass flux and heat flux. IRs always exhibit higher pressure drop penalties. This study also revealed the optimum design for microchannel with IRs, which depends on the operational parameters (e.g., mass flux and heat flux) of the microchannel heat sink.

Cardio-respiratory fitness (CRF) is a widespread essential indicator in Sports Science as well as in Sports Medicine. This study aimed to develop and validate a prediction model for CRF based on a 45 second self-test, which can be conducted anywhere. Criterion validity, test re-test study was set up to accomplish our objectives. Data from 81 healthy volunteers (age: 29 ± 8 years, BMI: 24.0 ± 2.9), 18 of whom females, were used to validate this test against gold standard. Nineteen volunteers repeated this test twice in order to evaluate its repeatability. CRF estimation models were developed using heart rate (HR) features extracted from the resting, exercise, and the recovery phase. The most predictive HR feature was the intercept of the linear equation fitting the HR values during the recovery phase normalized for the height2 (r2 = 0.30). The Ruffier-Dickson Index (RDI), which was originally developed for this squat test, showed a negative significant correlation with CRF (r = -0.40), but explained only 15% of the variability in CRF. A multivariate model based on RDI and sex, age and height increased the explained variability up to 53% with a cross validation (CV) error of 0.532 L ∙ min-1 and substantial repeatability (ICC = 0.91). The best predictive multivariate model made use of the linear intercept of HR at the beginning of the recovery normalized for height2 and age2; this had an adjusted r2 = 0. 59, a CV error of 0.495 L·min-1 and substantial repeatability (ICC = 0.93). It also had a higher agreement in classifying CRF levels (κ = 0.42) than RDI-based model (κ = 0.29). In conclusion, this simple 45 s self-test can be used to estimate and classify CRF in healthy individuals with moderate accuracy and large repeatability when HR recovery features are included.

Évaluation de la qualite de l\'eau et des niveaux bacteriologiques dans le tilapia du nil (oreochromis niloticus) du reservoir d\'aiba, nigeria, afrique de l\'ouest.Les activités anthropiques constituent une menace majeure pour la qualité des masses d\'eau. Cette étude a évalué la qualité de l\'eau et les niveaux bactériologiques dans le foie, les branchies et les tissus d\'Oreochromis niloticus dans le réservoir d\'Aiba. Le réservoir a été divisé à dessein en fonction des activités anthropiques; site d\'atterrissage des poissons et accessibilité dans trois zones d\'échantillonnage marquées Zone 1 (entrée), Zone 2 (centre) et Zone 3 (sortie) avec chaque zone ayant un site d\'atterrissage, Gaa Fulani, site d\'atterrissage et Oju odo respectivement. Des échantillons de poisson d\'un poids moyen de 200 g et des échantillons d\'eau ont été recueillis au hasard tous les quinze jours en trois exemplaires pendant six mois. Les valeurs moyennes de l\'analyse de l\'eau mesurées se situaient dans la plage tolérable pour les poissons, bien qu\'il y ait eu de légères variations dans les zones qui n\'étaient pas significatives (P <0.05) et significatives entre les mois. Escherichia coli et Staphylococcus aureus ont été observés sur le foie, les tissus et les branchies des échantillons de poisson et peuvent causer de la dysenterie, de la fièvre, de la diarrhée et une insuffisance rénale chez les humains. Les tissus des échantillons de poisson présentaient le nombre total moyen de microbes et de coliformes le plus élevé. Il est donc opportun que des stratégies de surveillance soient utilisées pour assurer le strict respect du niveau de polluants autour du réservoir afin d\'assurer une consommation sûre du poisson et l\'utilisation de l\'eau. Anthropogenic activities pose a major threat to the quality of water bodies. This study assessed the water quality and bacteriological levels in the liver, gills and tissues of Oreochromis niloticus (O. niloticus) in Aiba reservoir. The reservoir was purposively partitioned based on anthropogenic activities; fish landing site and accessibility into three sampling zones tagged Zone 1(inlet), Zone 2 (middle) and Zone 3 (outlet) with each zone having a fish landing site namely Gaa Fulani, landing site and Oju odo respectively. Fish samples with average weight of 200g and water samples were randomly collected fortnightly in triplicates for six months. Mean values of water analysis measured were within the tolerable range for fish although there were slight variations within the zones which were not significant (P<0.05) and significant among the months. Escherichia coli and Staphylococcus aureus were observed on the liver, tissues and gills of fish samples and can cause dysentery, fever, diarrhea and renal failure in humans. The tissues of fish samples had the highest mean total microbial and coliform count. It is therefore expedient that monitoring strategies be employed for strict adherence to level of pollutants around the reservoir to ensure safe consumption of fish and usage of water.

Controversy exists regarding the incidence and reproductive habits of Parapenaeopsis stylifera along the coast of Kerala, India. Results are reported of a detailed study on the different aspects of the reproductive biology based on the trawl catches landed at Neendakara Coast for a period of one year. This species breeds throughout the year with peak breeding activity in May and November. The monsoon catches consist of juveniles. Life span of the species is 2.5 years and total length at first maturity is 75 mm. Measures for the effective management of the species in the area are discussed.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field. 17 1