Two-phase heat transfer in small passages and microfinned surfaces - Fundamentals and applications

Micro channels and internally finned tubes are increasingly being utilized in the evaporators and condensers of refrigeration systems. The adoption of such geometries in the development of micro-cooling systems is first discussed in this paper. Recent work on flow boiling heat transfer and condensation in small to micro passages as well as on microfinned surfaces is then presented. The complex effect of diameter size on flow boiling patterns and heat transfer and correlations currently available in literature are summarized. Condensation in microfinned tubes and microchannels is then discussed

Genetic Determinants of Increased Outcrossing in Caenorhabditis elegans Following Dauer Diapause

Mating strategies, whether sexual or asexual, confer unique costs and benefits to populations and species that facilitate evolutionary processes. In wild isolates of Caenorhabditis elegans, mating strategies are dependent on developmental history. Outcrossing levels significantly increase when both hermaphrodites and males have transiently passed through the stress-resistant dauer diapause stage (postdauers). However, the molecular mechanisms of how life history can alter mating strategies have not been systematically explored. Mating behaviors of C. elegans can be attributed, in part, to sex-specific responses to ascaroside pheromone components. For example, high concentrations of the pheromone ascr#3 results in a strong avoidance response in hermaphrodites, but a slight attraction in males. We have demonstrated previously that postdauer hermaphrodites exhibit a decreased avoidance of ascr#3, which is the result of the downregulation of the osm-9 TRPV channel gene in postdauer ADL neurons. Thus, we hypothesized that sex-specific altered detection and/or response to pheromone components in postdauer animals could contribute to their increased outcrossing phenotype. To test this hypothesis, we conducted mating assays using N2 Bristol and strains carrying mutations in daf-3/SMAD and mut-16/Mutator genes, which are required for the downregulation of osm-9 in postdauer hermaphrodite ADL neurons. First, we determined that the outcrossing level of N2 Bristol is primarily correlated with the developmental history of males, with a smaller effect due to hermaphrodites. Interestingly, postdauer males did not downregulate osm-9 in their ADL neurons, but instead exhibited an increased ability to detect mates via pheromone compared to control males. Additionally, daf-3 mutants exhibited loss of the increased outcrossing phenotype in postdauers, illustrating the requirement of the TGF-β pathway in both males and hermaphrodites for this phenotype. Furthermore, the mut-16 strain exhibited negligible outcrossing, and attempts to rescue the outcrossing phenotype resulted in sterility due to gross morphological defects in the germline. Together, our results suggest a model whereby mating strategy is under combinatorial control of TGF-β and RNAi pathways

Household Constraints on Schooling by Gender: Empirical Evidence from Ethiopia

Using data collected during school-based surveys in two regions in Ethiopia, bivariate and multivariate analysis has been carried out to identify some of the important constraints to primary schooling. Problems in obtaining a representative sample of children not in school for this type of analysis are identified, and allowances are made for these problems, where possible. The results provide some evidence that well-nourished children from wealthier households whose mother and father are literate are more likely to attend and complete primary school. Furthermore, starting school at the official starting age of seven years and not repeating a grade increases the chances of completion. For children living within the vicinity of the school, opportunity costs do not appear to have a significant impact on the probability of attending or completing school, although girls in and out of school have a heavier work burden, relative to boys. Whilst similar factors are found to influence the probability of both boys and girls attending and completing school in the sample, their impact on girls is greater – undernourished girls from households lacking possessions, whose parents are illiterate, are 20 per cent less likely to attend school and 16 per cent less likely to complete school compared to a boy with these characteristics. Starting school above the official age and repeating a grade are also shown to reduce the chances of girls completing school by a slightly greater amount than boys. Statistical analyses of the kind used in this paper are not able to control adequately for cultural constraints to schooling, although these are recognised as potentially providing an additional important explanation for the gender gap

\u27Twas only an Irishman\u27s dream

https://digitalcommons.library.umaine.edu/mmb-vp/2568/thumbnail.jp

A Hybrid Resampling Approach for Multiclass Skewed Datasets and Experimental Analysis with Diverse Classifier Models

In real-life scenarios, imbalanced datasets pose a prevalent challenge for classification tasks, where certain classes are heavily underrepresented compared to others. To combat this issue, this article introduces DOSAKU, a novel hybrid resampling technique that combines the strengths of DOSMOTE and AKCUS algorithms. By integrating both oversampling and undersampling methods, DOSAKU significantly reduces the imbalance ratio of datasets, enhancing the performance of classifiers. The proposed approach is evaluated on multiple models employing different classifiers, and the results demonstrate its superiority over existing resampling measures, making it an effective solution for handling class imbalance challenges. DOSAKU's promising performance is a substantial contribution to the field of imbalanced data classification, as it offers a robust and innovative solution for improving predictive model accuracy and fairness in real-world applications where imbalanced datasets are common

Baby Shoes

https://digitalcommons.library.umaine.edu/mmb-vp/2837/thumbnail.jp

Reconstruction of Nonunion Tibial Fractures in War-Wounded Iraqi Civilians, 2006-2008: Better Late Than Never

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