No abstract

Molecular-genetic technology and statistical methods based on principles of population genetics provide valuable information to wildlife managers. Genetic data analyzed in a hierarchical, spatial context among individuals and among populations at micro-and macro-geographic scales has been widely used to provide information on the degree of population structure and to estimate rates of dispersal. Our goals were to (1) provide an overview of spatial statistics commonly used in empirical population genetics, and (2) introduce analytical designs that can be employed to extend hypothesis-testing capabilities by incorporating space-time interactions and by using information on habitat quality, distribution, and degree of connectivity. We show that genetics data can be used to quantify the degree of habitat permeability to dispersal and to qualify the negative consequences of habitat loss. We highlight empirical examples that use information on spatial genetic structure in areas of harvest derivation for admixed migratory species, wildlife disease, and habitat equivalency analysis.

This study investigates transient secondary flow in a rectangular curved microchannel in which the fluid is driven by the application of an external dc or ac electric field. The resultant flow field evolutions within the microchannel are simulated using the backwards Euler time stepping numerical method in order to clarify the relationship between the changes in the transverse flow field conditions and the intensity of the applied electric field. The transient secondary flow evolutions provide evidence of the growth and decay of vortices in the transverse section. As the applied dc or ac electric field intensity is activated, a small vortex appears in each corner of the microchannel. Both upper and lower corner vortices gradually grow in size and strength and finally merge to form a single vortex, which compresses the original recirculation in the upper and lower half of the transverse section. In this study, the formation of these vortices is investigated through total applied force per unit area existing in the flow. The velocity magnitude of the vortices can be as high as 15% of the core axial speed.

The current approaches remain insufficient for measuring chicken egg spoilage or present analytical limitations. This study aimed to complement the existing analyses and identify novel markers using liquid chromatography-high resolution mass spectrometry-based foodomics strategies. In the discovery set, comparative untargeted metabolomics was utilized to identify marker candidates in microbially inoculated chicken eggs. Markers were annotated by spectral matching with authentic standards, experimental libraries, or in silico fragmentation. In the validation set, targeted metabolomics was employed to verify the markers in stored chicken eggs from five farms. Statistical differences at a p-value < 0.001 revealed increases in lactic and 3-hydroxybutyric acids and decreases in phosphocholine, LPE(O-18:1), LPC(16:0), and LPC(18:0) in stored eggs. Receiver operating characteristic curve analysis of the six combined markers yielded an AUC of 0.956 and a sensitivity and specificity of ∼90%. Four phospholipids were highlighted as a novel class of spoilage markers. Our findings may contribute to further industrial implementation, benefiting the quality assurance and food safety of poultry egg production.

Previous studies have shown hypothyroidism was independently associated with nonalcoholic fatty liver disease (NAFLD) in adults, but few studies examined their relationships in pediatric populations. This study aimed to investigate the prevalence of NAFLD in pediatric congenital hypothyroidism (CHT) patients and to identify the association between CHT and NAFLD. This study enrolled pediatric CHT patients receiving levothyroxine treatment at one medical center from 2013 to 2014. Euthyroid subjects (ET) and transient hypothyroidism (THT) patients weaned off medication successfully after age 3 were selected for further comparison. Laboratory data including thyroid functions, liver functions, and metabolic profiles were obtained. The major outcome was the occurrence of NAFLD, diagnosed based on the findings of abdominal ultrasonography. One‐hundred and twenty‐nine subjects (47 in CHT, 47 in THT, and 35 in ET groups) were enrolled. The analysis showed higher fasting serum glucose, insulin, thyroxine (T4), and mean thyroid‐stimulating hormone (TSH) levels in the CHT group. NAFLD prevalence was higher in the CHT (23.4%) group than in the THT (8.5%) and the ET (5.7%) groups, demonstrating an increasing trend across three strata (X2linear‐by‐linear = 5.9, P < .05). The multivariate regression analysis showed obesity (β‐coefficient = 5.52, P < .05), CHT (β‐coefficient = 2.92, P < .05) and mean TSH levels (β‐coefficient = 0.24, P < .05) were independent risk factors for NAFLD. A positive correlation was found between TSH level and lipid profiles. CHT patients had higher risk of NAFLD despite treatment being initiated early in life. Close monitoring of metabolic profiles is warranted. Further research should examine ways to optimize the treatment for CHT patients in terms of prevention against NAFLD.