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11.
Samantha Bothwell Alex Kaizer Ryan Peterson Danielle Ostendorf Victoria Catenacci Julia Wrobel 《Biometrics》2023,79(3):2719-2731
“Smart”-scales are a new tool for frequent monitoring of weight change as well as weigh-in behavior. These scales give researchers the opportunity to discover patterns in the frequency that individuals weigh themselves over time, and how these patterns are associated with overall weight loss. Our motivating data come from an 18-month behavioral weight loss study of 55 adults classified as overweight or obese who were instructed to weigh themselves daily. Adherence to daily weigh-in routines produces a binary times series for each subject, indicating whether a participant weighed in on a given day. To characterize weigh-in by time-invariant patterns rather than overall adherence, we propose using hierarchical clustering with dynamic time warping (DTW). We perform an extensive simulation study to evaluate the performance of DTW compared to Euclidean and Jaccard distances to recover underlying patterns in adherence time series. In addition, we compare cluster performance using cluster validation indices (CVIs) under the single, average, complete, and Ward linkages and evaluate how internal and external CVIs compare for clustering binary time series. We apply conclusions from the simulation to cluster our real data and summarize observed weigh-in patterns. Our analysis finds that the adherence trajectory pattern is significantly associated with weight loss. 相似文献
12.
Samantha G. Robinson Katie M. Walker Henrietta A. Bellman Daniel Gibson Daniel H. Catlin Sarah M. Karpanty Shannon J. Ritter James D. Fraser 《The Journal of wildlife management》2023,87(1):e22325
Population declines of disturbance-dependent species due to suppression of natural disturbances are realized across ecosystems. The piping plover (Charadrius melodus; plover), a disturbance-dependent and conservation-reliant shorebird that nests on sandy beaches and barrier islands on the Atlantic Coast, was listed under the United States Endangered Species Act in 1986. In 2012, Hurricane Sandy landed on Fire and Westhampton islands, barrier island nesting sites for plovers in New York, USA. Hurricane Sandy was a natural disturbance in this system, creating abundant nesting habitat. The number of chicks produced by a pair, or a population, is a direct measure of reproductive output, and gaining a better understanding of productivity and chick behavior following large-scale habitat creation may improve plover habitat management and potentially species persistence. We evaluated the effects of landscape features on habitat selection, behavior, and survival of plover broods using logistic regression, generalized linear mixed effects models, and survival models. Plover broods selected flatter sites with less dense vegetation than available at random. Chick foraging rates were highest in moist substrates and were lower in areas of higher nesting plover density. Chick survival was greater for broods that hatched earlier in the breeding season and increased as chicks aged. Generally, providing access to sites with flatter, moist substrates will likely result in higher quality brood rearing habitat on the landscape. Ultimately, vegetation removal and habitat management may be needed to reduce plover nesting density and ensure sufficient habitat, which may in turn improve plover chick survival. Moreover, sustaining natural landscape disturbances such as those resulting from storms, and not taking actions to prevent hurricane-created overwash, will allow these landscape features to persist. 相似文献
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Varilla González Jean David Macedo Alves Flávio Bagnatori Sartori Ângela Lúcia de Oliveira Arruda Rosani do Carmo 《Journal of plant research》2023,136(4):453-481
Journal of Plant Research - The Pterocarpus clade includes 23 genera previously attributed to different Fabaceae tribes. The recent rearrangements of many genera in the clade do not recognize... 相似文献
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Inhibition of cholinesterase (ChE) activity produced by a single acute intraperitoneal administration of dimethoate was studied in the wood mouse, Apodemus sylvaticus, and the common shrew, Sorex araneus, under laboratory conditions. ChE values from serum and whole blood were compared with those obtained from brain in order to obtain a non-destructive tool for predicting the severity of brain acetylcholinesterase (AChE) inhibition. In addition, serum and brain inhibition following oral exposure to dimethoate was also measured in the wood mouse. Normal ChE activity was higher in the brain and whole blood of the shrews than in wood mice. There was no difference between species in serum ChE activity. Exposure to dimethoate caused a dose-dependent reduction in ChE activity and there was a significant recovery in activity with increasing time after administration. In both species, serum and whole blood were more sensitive than brain for revealing organophosphate-induced ChE inhibition and serum was more sensitive than whole blood. Statistically significant relationships were defined between whole blood and brain ChE activity and between serum and brain ChE activity. Compared with serum, whole blood ChE activity was the more accurate predictor of brain AChE levels. The relationships between brain and serum ChE activity did not appear to be affected by the route of administration of the pesticide. 相似文献
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Fabrizio Barberini Stefano Sartori Dr. Pietro Motta Jonathan Van Blerkom 《Cell and tissue research》1978,190(2):207-222
Summary Changes occurring on the surface of the uterine luminal epithelium of the rabbit during the estrous and progestational stages of the reproductive cycle were examined by scanning and transmission electron microscopy. The findings demonstrate that the uterine epithelium, or endometrium, contains two cell types: ciliated cells and nonciliated, microvillous cells. In estrous animals, ciliated cells, although not very numerous, were usually observed in small groups. However, at increasing intervals of time following mating, ciliated cells progressively disappeared from the endometrium until approximately eight to ten days post coitum, when they became scare. From several hours to four to five days following mating, extensive changes occurred on the surfaces of microvillous cells. When observed by TEM, these elements contained organelles typical of cells involved in the synthesis and secretion of glycoproteins. Furthermore, microvillous cells during this period displayed numerous apical protrusions of different sizes and shapes and containing material of varying electron density. Parallel SEM examinations of the same material confirmed the presence of these protrusions. Some of the protrusions appeared as spheroidal masses attached to the cytoplasm by means of a cytoplasmic strand. Other surface masses were clearly unattached to the cell surface and were distributed (1) on the surface of microvillous cells, (2) on the cilia of adjacent ciliated cells, and (3) on the surface of spermatozoa.Changes occurring on the luminal surface during the early postcoital period are interpreted as an expression of morphodynamic processes likely involving coupled secretion (exocytosis) and resorption (endocytosis) of luminal material. The observations presented here also demonstrate that between six and ten days post coitum, the rabbit endometrium contained increasing numbers of enlarged, nonciliated cells that probably arose by the fusion of smaller, microvillous elements.The work reported here was supported by C.N.R. contracts No. CT 760128809 and CT 77014239 (to P.M.) and NIH. Grant HD-04274 (to J.V.B.) 相似文献
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Julian F.B. Mercer Trevor Stevenson Samantha A. Wake Georgia Mitropoulos James Camakaris David M. Danks 《生物化学与生物物理学报:疾病的分子基础》1991,1097(3):205-211
The concentrations of copper, zinc and metallothionein-I (MT-I) mRNA were determined in the liver, kidney and brain of the brindled mutant mouse from birth until the time of death. Despite accumulation of copper in the kidney of the mutant, MT-I mRNA concentrations were normal. There was no difference between the MT-I mRNA in the brain of mutant and normal in the first 10 days of life, but after day 10 metallothionein mRNA levels were increased in the mutant. The concentration of copper was very low in the liver of the mutant, and on day 6 after birth the metallothionein mRNA was also reduced by about 50%. This reduction was not seen in copper-deficient 6-day-old pups, despite very low hepatic copper levels. This suggests that the lower hepatic MT-I mRNA in the day 6 brindled mouse was not simply due to the reduction in hepatic copper and also that hepatic copper is not regulating metallothionein gene expression the liver of neonatal mice. After day 12 hepatic MT-I mRNA levels were elevated in mutant and in copper deficient mice, both of which die at 14 to 16 days. These increases and the increase in brain MT-I mRNA in older mutant mice are likely to be caused by stress. Overall the results support the conclusions that the brindled mutation does not cause a constitutive activation of the metallothionein genes, and that the differences in metallothionein mRNA between mutant and normal are most probably secondary consequences of the mutation. 相似文献
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Research across groups and methods consistently finds a gender difference in patterns of specificity of genital response; however, empirically supported mechanisms to explain this difference are lacking. The information-processing model of sexual arousal posits that automatic and controlled cognitive processes are requisite for the generation of sexual responses. Androphilic women’s gender-nonspecific response patterns may be the result of sexually-relevant cues that are common to both preferred and nonpreferred genders capturing attention and initiating an automatic sexual response, whereas men’s attentional system may be biased towards the detection and response to sexually-preferred cues only. In the present study, we used eye tracking to assess visual attention to sexually-preferred and nonpreferred cues in a sample of androphilic women and gynephilic men. Results support predictions from the information-processing model regarding gendered processing of sexual stimuli in men and women. Men’s initial attention patterns were gender-specific, whereas women’s were nonspecific. In contrast, both men and women exhibited gender-specific patterns of controlled attention, although this effect was stronger among men. Finally, measures of attention and self-reported attraction were positively related in both men and women. These findings are discussed in the context of the information-processing model and evolutionary mechanisms that may have evolved to promote gendered attentional systems. 相似文献
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There have been several reports that individuals with Fragile X syndrome (FXS) and animal models of FXS have communication deficits. The present study utilized two different call classification taxonomies to examine the sex‐specificity of ultrasonic vocalization (USV) production on postnatal day (PD8) in the FVB strain of Fmr1 knockout (KO) mice. One classification protocol requires the investigator to score each call by hand, while the other protocol uses an automated algorithm. Results using the hand‐scoring protocol indicated that male Fmr1 KO mice exhibited longer calls (P = .03) than wild types on PD8. Male KOs also produced fewer complex, composite, downward, short and two‐syllable call‐types, as well as more frequency steps and chevron call‐types. Female heterozygotes exhibited no significant changes in acoustic or temporal aspects of calls, yet showed significant changes in call‐type production proportions across two different classification taxonomies (P < .001). They exhibited increased production of harmonic and frequency steps calls, as well as fewer chevron, downward and short calls. According to the second high‐throughput analysis, female heterozygotes produced significantly fewer single‐type and more multiple‐type syllables, unlike male KOs that showed no changes in these aspects of syllable production. Finally, we correlated both scoring methods and found a high level of correlation between the two methods. These results contribute further knowledge of sex differences in USV calling behavior for Fmr1 heterozygote and KO mice and provide a foundation for the use of high‐throughput analysis of neonatal USVs. 相似文献