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1.
Summary We used an automated technique for the observation and quantification of zooplankton swimming behavior to study the behavioral responses of two congeneric, herbivorous, freshwater copepod prey to a copepod predator (Limnocalanus macrurus). One prey, Diaptomus sicilis, often co-occurs with Limnocalanus, while previous studies indicated that the zoogeographic distribution of the second prey, Diaptomus oregonensis, was independent of the predator. We found that in the presence of Limnocalanus, D. sicilis swims more slowly and with less hopping and jumping than D. oregonensis. Diaptomus sicilis is also attacked and consumed by the predator Limnocalanus macrurus less frequently than D. oregonensis. We suggest that the faster, noisier swimming of D. oregonensis increases its vulnerability to Limnocalanus. The behavioral defenses to both prey are induced by the presence of the predator, and may represent two different anti-predator strategies, crypsis and avoidance for D. sicilis and D. oregonensis respectively. In a zoogeographical analysis D. oregonensis occurs at densities below D. sicilis in lakes where Limnocalanus is at elevated abundances, while in low-predator lakes the opposite is true. This distribution pattern supports our experimental results, and suggests that D. sicilis is adapted to survive with Limnocalanus, while D. oregonensis is not.  相似文献   
2.
Objective: To compare weight-specific and global psychosocial concerns and health-compromising behaviors among overweight and nonoverweight youth across gender and ethnicity. Methods: A cross-sectional school-based survey of 31,122 adolescents in grades 7 to 12. Based on self-reported heights and weights, respondents were categorized as nonoverweight (body mass index (BMI) <85th percentile), moderately overweight (85th percenile <BMI <95th percentile), or severely overweight (BMI >95th percentile). Results: Global psychosocial concerns, such as emotional well-being, suicidal ideation, future job concerns, and peer concerns, did not differ greatly between nonoverweight, moderately overweight, and severely overweight adolescents. Substance abuse behaviors were equally or less prevalent among the overweight group. Overweight girls were significantly less likely to consume alcohol, whereas overweight boys were at lower risk for marijuana use. In contrast, overweight youth were more likely to perceive their health as only fair or poor and were more likely to express weight-specific concerns and engage in behaviors such as chronic dieting and binge eating than nonoverweight youth. Overweight American Indian girls perceived their physical health more positively than nonoverweight American Indian girls. Strong associations were found between overweight status and chronic dieting among African American boys and girls. Conclusions: Nutritional counseling and educational programs need to address the weight-specific concerns and behaviors of overweight adolescents. However, assumptions regarding global psychosocial concerns and health-compromising behaviors among overweight adolescents of different genders and ethnicities should be avoided. These broad issues need to be explored in more depth at both the research and intervention levels.  相似文献   
3.
Synopsis Predation on eggs of the angelfish, Centropyge ferrugatus, was observed in the coral reefs of Sesoko Island, Okinawa, Japan. This angelfish released pelagic eggs in pairs at sunset after slow ascents. Of 99 matings of this angelfish, an omnivorous damselfish Amblyglyphidodon curacao approached in 25, and fed on the released eggs in eight cases. The spawning angelfish never attacked the egg-predators. Pairs of this angelfish avoided the egg-predators by delaying mating for several minutes during courtships, and by frequent changes of spawning sites. Of the 25 matings targeted by the egg-predators, the angelfish successfully avoided predation in 17 cases. Eight matings were failures mainly due to lack of any attempt to elude the predator, suggesting that the delayed matings on multiple spawning sites are effective anti-egg predator behaviors.  相似文献   
4.
The digital twin technique has been broadly utilized to efficiently and effectively predict the performance and problems associated with real objects via a virtual replica. However, the digitalization of twin electrochemical systems has not been achieved thus far, owing to the large amount of required calculations of numerous and complex differential equations in multiple dimensions. Nevertheless, with the help of continuous progress in hardware and software technologies, the fabrication of a digital twin‐driven electrochemical system and its effective utilization have become a possibility. Herein, a digital twin‐driven all‐solid‐state battery with a solid sulfide electrolyte is built based on a voxel‐based microstructure. Its validity is verified using experimental data, such as effective electronic/ionic conductivities and electrochemical performance, for LiNi0.70Co0.15Mn0.15O2 composite electrodes employing Li6PS5Cl. The fundamental performance of the all‐solid‐state battery is scrutinized by analyzing simulated physical and electrochemical behaviors in terms of mass transport and interfacial electrochemical reaction kinetics. The digital twin model herein reveals valuable but experimentally inaccessible time‐ and space‐resolved information including dead particles, specific contact area, and charge distribution in the 3D domain. Thus, this new computational model is bound to rapidly improve the all‐solid‐state battery technology by saving the research resources and providing valuable insights.  相似文献   
5.
Decreased bridging integrator 1 (BIN1) expression has great significance in promoting the progression of malignant tumors. Reduced messenger RNA expression is partly due to aberrant alternative splicing (AS). However, the AS status of BIN1 and its correlation with BIN1 inactivation in non–small cell lung cancer (NSCLC) remains poorly defined. Here we reported that BIN1 inactivation was not related to DNA methylation in NSCLC. Importantly, BIN1 with exon 12A inclusion (BIN1+12A isoform), the most frequent aberrant splicing variant in tumors was also observed in NSCLC, and might be accounted for BIN1 inactivation. Furthermore, we showed that the aberrant splicing of BIN1 was under the control of serine and arginine-rich factor 1 (SRSF1) in NSCLC. In addition, colony formation assay showed that BIN1+12A isoform could abolish the tumor-inhibiting ability of BIN1 in NSCLC cells. Meanwhile, transwell, wound healing and apoptosis experiments demonstrated that the occurrence of BIN1+12A could abrogate the invasion suppressing activity and proapoptotic property of BIN1 in NSCLC. Significantly, we also found that BIN1+12A isoform neutralized the tumor-suppressing functions of BIN1 via affecting its subcellular localization. Altogether, these data revealed an aberrant splicing phenomenon which abated the expression and tumor-inhibiting activity of BIN1 in NSCLC, and the related mechanisms were associated with SRSF1.  相似文献   
6.
ABSTRACT

Chronotype reflects time of day preferences for performing daily activities. Previous research within Asian and European cohorts indicates evening chronotype is associated with elevated cardiometabolic risk. However, evidence is limited from population-based US cohorts, particularly among women in whom evening chronotype prevalence may become higher after middle-age, coinciding with life stages associated with higher cardiovascular disease (CVD) risk. This cross-sectional study evaluated associations of chronotype with overall cardiovascular health (CVH), health behaviors, and cardiometabolic risk factors among 506 women (mean age = 37 ± 16y, 62% racial/ethnic minority) in the American Heart Association (AHA)’s Go Red for Women Strategically-Focused Research Network cohort at Columbia University (New York City, NY, USA). Chronotype was assessed using the validated Morningness-Eveningness Questionnaire (MEQ) and categorized as “evening”, “intermediate”, and “morning” chronotypes. Health behaviors (diet, physical activity, and sleep) were assessed using validated questionnaires. Anthropometrics, clinical blood pressure, and blood biomarkers were assessed at the clinic visit. CVH was evaluated using the AHA Life’s Simple 7 (LS7) metrics; LS7 scores of 0–8 and 9–14 were considered indicative of poor and moderate-to-high CVH, respectively. Linear and logistic regression models adjusted for age, race/ethnicity, education, health insurance, and menopausal status were used to examine associations of MEQ scores and chronotype categories with overall CVH, clinical cardiometabolic risk factors, and health behaviors. Overall, 13% of women identified as evening chronotypes, while 55% and 32% reported being intermediate and morning types. In linear models, higher MEQ scores were associated with higher AHA LS7 scores (β(SE) = 0.02(0.01); p = .014), indicative of more favorable CVH, and with health behaviors not included in the LS7. Higher MEQ scores were also associated with lower Pittsburgh Sleep Quality Index, i.e. better sleep quality, (β(SE) = ?0.07(0.02), p < .0001), lower insomnia severity (β(SE) = ?0.14(0.01), p < .0001), shorter time to fall asleep (β(SE) = ?0.28(0.14), p = .044), and less sedentary time (β(SE) = ?0.11(0.03), p = .001). In logistic regression models, evening chronotype, compared to intermediate/morning type, was associated with higher odds of having poor CVH (OR(95%CI):2.41(1.20–4.85)), not meeting AHA diet (OR(95%CI):2.89(1.59–5.23)) and physical activity guidelines (OR(95%CI):1.78(1.03–3.07)), and having short sleep (OR(95%CI):2.15(1.24–3.73)) or insomnia (OR(95%CI):2.69(1.53–4.75)). The evening type compared to morning type was also associated with being a current smoker (OR(95%CI):2.14(1.02–4.52)) and having poor sleep quality (OR(95%CI:2.35(1.27–4.37)) and long sleep onset latency (OR(95%CI:1.89(1.00–3.56)). In our cohort of women, evening chronotype was related to poor CVH, likely driven by its influence on health behaviors. These findings, although warranting confirmation prospectively in other populations, suggest chronotype is an important factor to consider and possibly target when designing lifestyle interventions for CVD prevention.  相似文献   
7.
Birds that nest on the ground in open areas, such as Piping Plovers (Charadrius melodus) and Interior Least Terns (Sternula antillarum athalassos), are exposed to high temperatures in thermally stressful environments. As a result, some ground-nesting avian species have adapted behavioral strategies to maintain thermal regulation of eggs and themselves. We assessed the impact of sand temperature on shorebird nesting behaviors by installing video cameras and thermocouples at 52 Least Tern and 55 Piping Plover nests on the Missouri River in North Dakota during the 2014–2015 breeding seasons. Daily duration and frequency of shading behaviors exhibited a nonlinear relationship with temperature; therefore, we used segmented regressions to determine at what threshold temperature (mean temperature = 25.7C for shading behavior daily frequency and mean temperature = 25.1C for shading behavior daily duration) shorebird adults exhibited a behavioral response to rising sand temperatures. Daily nest attendance of both species decreased with increasing sand temperatures in our system. Frequency and duration of daily shading behaviors were positively correlated with sand temperatures above the temperature threshold. Piping Plovers exhibited more and longer shading behaviors above and below the temperature thresholds (below: frequency = 10.30 ± 1.69 se, duration = 7.29 min ± 2.35 se; above: frequency = 59.27 ± 6.87 se) compared to Least Terns (below: frequency = −1.37 ± 1.98 se, duration = −0.73 min ± 1.51 se; above: frequency = 31.32 ± 7.29 se). The effects of sand temperature on avian ground-nesting behavior will be critical to understand in order to adapt or develop recovery plans in response to climate change.  相似文献   
8.
Many complex behaviors are genetically hardwired. Based on previous findings on genetic control of mating and other behaviors in invertebrate and mammalian systems, I suggest that genetic control of complex behaviors is modular: first, dedicated genes specify different behavioral patterns; secondly, separable genetic networks govern distinct behavioral components. I speculate that modular genetic encoding of complex behaviors may in part reflect modularity in brain development and function. Editor's suggested further reading in BioEssays From songs to synapses: Molecular mechanisms of birdsong memory Abstract  相似文献   
9.
Objective: This study examined the relationship between internalization of negative weight‐based stereotypes and indices of eating behaviors and emotional well‐being in a sample of overweight and obese women. Research Method and Procedures: The sample was comprised of 1013 women who belonged to a national, non‐profit weight loss organization. Participants completed an on‐line battery of self‐report questionnaires measuring frequency of weight stigmatization and coping responses to deal with bias and symptoms of depression and self‐esteem, attitudes about weight and obesity, and binge eating behaviors. In addition, participants were asked to list the most common weight‐based stereotypes and whether they believed them to be true or false. Results: Participants who believed that weight‐based stereotypes were true reported more frequent binge eating and refusal to diet in response to stigma experiences compared with those who reported stereotypes to be false. The degree to which participants believed stereotypes to be true or false was not related to types or amount of stigma experiences reported, self‐esteem, depression, or attitudes toward obese persons. In addition, engaging in weight loss strategies as a response to bias was not predicted by stereotype beliefs or by actual stigma experiences, regardless of the amount or types of stigma reported. Discussion: These findings suggest that obese individuals who internalize negative weight‐based stereotypes may be particularly vulnerable to the negative impact of stigma on eating behaviors and also challenge the notion that stigma may motivate obese individuals to engage in efforts to lose weight. This study highlights a new area of research that warrants attention to better understand weight stigma and its potential consequences for health.  相似文献   
10.
Objective: Eating in the absence of hunger (EAH) may be a genetically influenced phenotype of overweight children, but evidence is limited. This research evaluated the heritability (h2) of EAH and its association with overweight among Hispanic children 5 to 18 years old. Genetic and environmental associations of EAH with overweight, fat mass, and key hormonal regulators of food intake were also evaluated. Research Methods and Procedures: A family design was used to study 801 children from 300 Hispanic families. Weighed food intakes were used to measure EAH after an ad libitum dinner providing 50% of estimated energy needs. Fasting ghrelin, amylin, insulin, and leptin were measured by immunoassays. Measured heights, weights, and fat mass (using DXA) were obtained. Total energy expenditure (TEE) was measured by room respiration calorimetry. Results: On average, children consumed 41% of TEE at the dinner meal, followed by an additional 19% of TEE in the absence of hunger. Overweight children consumed 6.5% more energy at dinner (p < 0.001) and 14% more energy in the absence of hunger (p < 0.001) than non‐overweight children. Significant heritabilities were seen for EAH (h2 = 0.51) and dinner intake (h2 = 0.52) and for fasting levels of ghrelin (h2 = 0.67), amylin (h2 = 0.37), insulin (h2 = 0.37), and leptin (h2 = 0.34). Genetic correlations were seen between eating behavior and fasting hormones, suggesting common underlying genes affecting their expression. Discussion: This research provides new evidence that overweight Hispanic children exhibit elevated levels of hyperphagic eating behaviors that are influenced by genetic endowment.  相似文献   
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