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The niche variation hypothesis (NVH) predicts that populations with wider niches exhibit greater morphological variation through increased interindividual differences in both niche and morphology. In this study, we examined niche–trait relationships in three passerine species (Cyanoderma ruficeps, Sinosuthora webbiana, and Zosterops simplex). A total of 289 C. ruficeps from 7 sites, 259 S. webbiana from 8 sites, and 144 Z. simplex from 6 sites were sampled along an elevation gradient (0–2,700 m) in Taiwan from 2009 to 2017. We measured bill traits (length, width, and depth of bill) and body size traits (length of head, tarsus, and wing) of the birds, which were reduced to four principal components (bill PC1, bill PC2, body size PC1, and body size PC2). We collected feather tissues for stable carbon and nitrogen isotope analyses to quantify their isotope niche. We quantified interindividual differences in isotope space and trait space with four diversity metrics (divergence, dispersion, evenness, and uniqueness) and tested whether interindividual differences in isotope space and trait space are positively associated. We quantified population isotope niche width by Bayesian ellipse area and population morphological variation by variances of the PCs. The results showed that individual uniqueness in isotope niche and bill morphology (average closeness of individuals within the population isotope/trait space) were positively associated across three species. Furthermore, isotope niche width and bill PC1 (reflecting the size of bill) variation at population level were also positively associated across the three species, supporting the NVH. Of the three species, C. ruficeps and S. webbiana showed stronger support for the NVH than Z. simplex, possibly due to the latter having narrower elevational distribution and a more specialized, plant‐based diet. The diversity metrics represented different aspects of interindividual differences in niche/trait space, and for the passerines, individual uniqueness appeared to play an important role in their niche–trait dynamics., This study provided empirical evidence for the niche variation hypothesis in three passerine species (Cyanoderma ruficeps, Sinosuthora webbiana, and Zosterops simplex) in Taiwan. All three species showed positive associations between isotope niche width and bill size variation. Furthermore, all three species shared the same pattern that as individual birds occupied unique bill trait space within the population, they also tended to occupy unique isotope space, suggesting niche width expansion at population level through morphological differentiation at individual level.

Highlights • The National Marrow Donor Program (NMDP) received preliminary search requests for over 3300 domestic and 3700 international allogeneic hematopoietic cell transplant candidates during the initial phase of the coronavirus disease 2019 (COVID-19) pandemic. • Despite a decrease in preliminary search requests, the number of unrelated donor grafts infused at domestic transplant centers following the initial phase of COVID-19 was only 4% less than the same period of time 1 year earlier. • Of over 2800 transportation legs and over 1600 transports completed through the NMDP, only 1 product was delivered outside of the requested time window in the initial period after COVID-19., The impact of the coronavirus disease 2019 (COVID-19) pandemic on hematopoietic cell transplant (HCT) donor registries and transplant center (TC) practices is underreported. This article reports on the National Marrow Donor Program (NMDP) Be The Match Registry and its coordinating the provision of unrelated donor (URD) products to domestic and international TCs during the initial 3 months of the COVID-19 pandemic (March through May 2020). Specifically, NMDP data are presented for disease indications for transplant, URD search volumes and availability, graft requests and processing, courier utilization and performance, and conversion rates from formal donor search and workup to graft collection and shipment. Data following the onset of COVID-19 are compared to the immediate 3 months prior to the COVID-19 pandemic (December 2019 through February 2020) and the same quarter 1 year prior to COVID-19 (March through May 2019). During the initial onset of COVID-19 and compared to 1 year prior, TCs requested and the NMDP performed less donor searches. More multiple URD and direct to workup requests were processed by the NMDP, which likely reflected reductions in donor availability. Yet TCs continued to perform allogeneic transplants for acute disease indications like acute leukemia and myelodysplasia, using more cryopreserved grafts than before COVID-19. In comparison to prepandemic patient cycle conversion rates and durations, the NMDP was able to convert patient cycles at nearly the same or higher rates and in similar or shorter periods of time. Last, despite significant challenges caused by the pandemic, including interruptions in domestic courier services and travel restrictions, graft products were delivered to and received by TCs in similar periods of time than before COVID-19. Taken together, these data show that NMDP service line operations continued to function effectively during the early phases of the COVID-19 pandemic, ensuring requests for and delivery of URD products to domestic and international allogeneic HCT recipients.

Niche variation at population level mediates niche packing (i.e. patterns of species' spread within the niche space) and species coexistence at community level. Competition and ecological opportunity (resource diversity) are two of the main mechanisms underlying niche variation. Dense niche packing could occur through increased niche partitioning or increased niche overlap. In this study, we used stable carbon and nitrogen isotope data of 635 individual rodents from four species across nine sites in the montane region of a subtropical island to test the effects of competition and ecological opportunity on population isotope niche size, inter-individual niche difference within population and interspecific niche overlap within community. We used the Bayesian Standard Ellipse Area (SEAB, the ellipse area enclosed by carbon and nitrogen isotope values of organisms on a bi-plot) to estimate population niche size and interspecific niche overlap. Inter-individual niche difference within population was quantified as isotopic divergence and isotopic uniqueness. We used rodent abundance (the number of unique individuals captured) to measure competition and plant isotope niche size (plant SEAB) to measure ecological opportunity. The rodents experienced competition as evidenced by a negative relationship between population change rate and conspecific abundance. Rodent population niche size increased with ecological opportunity but not competition. The inter-individual niche difference (isotopic uniqueness) increased with competition (interspecific competition only) but not ecological opportunity. At community level, interspecific niche overlap (herbivore-omnivore pair only) increased with competition (the combined abundance of the pair) but not ecological opportunity. This study demonstrated that isotope niche variation of the rodents could be hierarchically influenced by ecological opportunity and competition, with the former setting the limit of population niche size across communities and the latter shaping inter-individual niche difference and interspecific niche overlap within communities. Under strong intraspecific competition and limited ecological opportunity for niche expansion, individuals may choose to increase their isotopic uniqueness from conspecifics at the cost of overlapping with heterospecifics of different trophic roles within the community niche space as overall competition increases. Denser niche packing of these rodent communities might be achieved through increased niche overlap.族群層級之生態棲位變異可調節群聚層級之生態棲位堆疊(亦即物種在生態棲位空間中的分佈樣態)以及物種共存。競爭與生態機會(資源豐度)是影響生態棲位變異的兩個重要機制。生態棲位區隔或生態棲位重疊增加，都有可能導致密集的生態棲位堆疊。 本研究利用亞熱帶島嶼山區9個地點的4個齧齒目物種共635隻個體之穩定碳、氮同位素資料，探討競爭與生態機會對族群生態棲位大小、族群內個體間生態棲位差異以及群聚內物種間生態棲位重疊的影響。 我們使用貝式標準橢圓形面積(縮寫為SEAB，亦即在碳、氮同位素兩軸上包括大部分個體之橢圓形面積)估算族群生態棲位面積以及物種間生態棲位重疊度。個體間生態棲位差異則是以同位素分歧度與同位素獨特性進行量化。我們使用各物種的族群數量(亦即每地點捕捉到的個體數)量化競爭，並使用植物同位素棲位面積(植物SEAB)量化生態機會。 各物種皆受到種內競爭影響，隨著族群數量越高，族群變化率越低。族群生態棲位面積隨生態機會增加而變大，但不受競爭的影響。個體間生態棲位差異(同位素獨特性)隨競爭(種間)增加而增加，但不受生態機會的影響。在群聚層級上，種間生態棲位重疊度(植食性與雜食性物種間)隨競爭(成對兩物種之總族群數量)增加而增加，但不受生態機會的影響。 本研究顯示齧齒目動物生態棲位變異可能同時受到生態機會與競爭的影響，在跨群聚的較大尺度上，前者限制族群生態棲位的大小，在群聚內的較小尺度上，後者影響個體間生態棲位差異與物種間生態棲位重疊。在種內競爭激烈且生態機會有限的情況下，隨著群聚內整體競爭(包含種內與種間)壓力增加，個體可能會選擇增加同位素獨特性，即便他們需付出與不同食性之異種生態棲位重疊度增加的代價。因此，這些齧齒目動物群聚可能是透過增加生態棲位重疊度達到更密集的生態棲位堆疊。.

Rates of suicide in the US Army continue to rise, and by some accounts exceed the general population. This increase has renewed efforts to identify protective factors that may inform novel suicide prevention strategies. Previous research has demonstrated that a sense of purpose in life and perceived cohesion with military peers are related to a reduction in the severity of suicidal ideation (SI). Additionally, research in military samples supports decreased SI in Soldiers who endorse that their leaders convey a sense of purpose and meaning in their shared mission. However, no work has investigated whether these leadership styles relate to a sense of felt purpose and perceived cohesion in Soldiers and thus the indirect effect of these leadership styles on SI. Active duty Army Soldiers (n = 1,160) completed self-report measures of purpose in life (PiL), perceived cohesion, ethical leadership, loneliness, and SI. Indirect effect analyses were conducted to determine how leadership behaviors indirectly relate to SI through PiL and perceived cohesion. Indirect effect analyses revealed that ethical leadership had an indirect effect on reduced SI through increased PiL. In the same parallel indirect effect analysis, ethical leadership was related to less SI through increased perceived cohesion and decreased loneliness sequentially. Enhanced leadership training that effectively increases Soldier purpose may be an important primary prevention tool to mitigate the effect of suicide risk factors. This primary prevention strategy may help augment existing suicide surveillance and clinical prevention efforts to reduce Soldier risk for suicide.

Background Quantity discrimination, the ability to discriminate a magnitude of difference or discrete numerical information, plays a key role in animal behavior. While quantitative ability has been well documented in fishes, birds, mammals, and even in previously unstudied invertebrates and amphibians, it is still poorly understood in reptiles and has never been tested in an aquatic turtle despite the fact that evidence is accumulating that reptiles possess cognitive skills and learning ability. To help address this deficiency in reptiles, we investigated the quantitative ability of an Asian freshwater turtle, Mauremys sinensis, using red cubes on a white background in a trained quantity discrimination task. While spontaneous quantity discrimination methods are thought to be more ecologically relevant, training animals on a quantity discrimination task allows more comparability across taxa. Results We assessed the turtles’ quantitative performance in a series of tests with increasing quantity ratios and numerosities. Surprisingly, the turtles were able to discriminate quantities of up to 9 versus 10 (ratio = 0.9), which shows a good quantitative ability that is comparable to some endotherms. Our results showed that the turtles’ quantitative performance followed Weber’s law, in which success rate decreased with increasing quantity ratio across a wide range of numerosities. Furthermore, the gradual improvement of their success rate across different experiments and phases suggested that the turtles possess learning ability. Conclusions Reptile quantitative ability has long been ignored and therefore is likely under-estimated. More comparative research on numerical cognition across a diversity of species will greatly contribute to a clearer understanding of quantitative ability in animals and whether it has evolved convergently in diverse taxa.

Litter and vegetation under forest canopy (i.e., understory vegetation) are known to reduce soil erosion and contribute substantially to evapotranspiration. However, previous studies rarely examined understory water interception. We conducted a comprehensive study of rainfall partitioning using a water balance equation that included both overstory and understory components in a Chinese fir (Cunninghamia lanceolata) plantation and a nearby naturally regenerated Castanopsis (C. carlesii) forest of similar age in southeastern China. Understory interception was measured by submerging understory components (vegetation and litter) in water for 24 h, which gave an estimate of the amount of water retained (i.e., water holding capacity). The total interception loss of rainfall events (>9.8 mm) that generated surface runoff converged between the two forests, a result of a smaller overstory interception loss (20%) coupled with a greater understory interception loss (14%) in the Chinese fir plantation relative to the Castanopsis forest (overstory 25% and understory 11%). The convergence of the total interception contributed to the convergence of the surface runoff, 1% of the rainfall in both forests. Furthermore, the throughfall partition (78%) was greater whereas the stemflow partition (2%) was smaller in the Chinese fir plantation relative to the Castanopsis forest (throufhfall 70% and stemflow 5%). These patterns in rainfall partitioning could be explained by the greater development of the understory vegetation (hence greater understory interception loss) in the Chinese fir plantation, lower canopy leaf area index (hence smaller overstory interception loss and greater throughfall), and rougher barks (hence smaller stemflow) of Chinese fir trees compared to that of Castanopsis trees. Our study illustrated that a comprehensive evaluation of interception loss must take into account understory components.

Respiration, sensory input, movement, and molting rely on crustacean body regions being free of fouling. While the grooming appendages of shrimps have been described, few studies have documented the functional morphology of grooming appendages in brachyuran crabs. Because shrimps and brachyurans have very different body morphology and grooming behaviors, their grooming setae may vary. The morphology of grooming appendages of blue (Callinectes sapidusRathbun, 1896) and stone (Menippe mercenaria (Say, 1818)) crabs were investigated to gain better insight into their efficiencies in decreasing fouling. Callinectes sapidus is an active swimmer, migrates through currents across estuaries, spends less time grooming, and is exposed to more environmental variants in contrast to M. mercenaria, which has a lower activity level and spends more time grooming. To compensate for this higher activity level and lower grooming time budget, C. sapidus was predicted to have more setal types on its grooming appendages as compared to M. mercenaria. Thirteen different body appendages/regions involved in grooming are described in both species by using scanning electron and light microscopy. We documented the morphology, presence or absence of setal patches, and types of setae in 104 different grooming appendages and groomed body regions. Of 25 types of setae, nine are unique to C. sapidus, rejecting the hypothesis that C. sapidus have more diverse grooming setae. Menippe mercenaria has denser setal patches and less fouling than C. sapidus. Nine new setal types are described. Fouling, setal diversities, and functions that correspond to grooming behaviors are discussed.

Phylogenetic analysis has shown that males' propensity to engage in aggressive encounters is associated with females having greater longevity. Here, we confirm the causal link between aggression and reduced longevity by looking at an egg-eating snake (Oligodon formosanus) in which females defend territories in the presence of sea turtle eggs. We monitored aggressiveness and survival at two sites: a control site with a stable supply of turtle eggs, and a second site where we collected data before and after a storm that eroded the beach on which turtles nested, thus leading to a loss of territoriality. We show that territoriality was the driver behind higher injury rates in females. Territorial females also had lower survival and decreased longevity compared with the nonterritorial males, but these differences disappeared when females were not territorial. Our study demonstrates how resource availability can influence the evolution of sex-specific patterns of survival across vertebrates.

Background Understanding how wild species respond to novel situations with associated risk can provide valuable insights for inter-specific behavioral variation and associations with pace-of-life (POL). Rodents, a globally distributed and diverse taxonomic group, have been the subjects of countless studies emulating risky situations. Controlled laboratory experiments with a focus on wild-caught species provide the opportunity to test fine-scale behavioral responses to contexts of risk with ecological implications. For example, assessing the importance of predator cues eliciting antipredator responses, as well as whether wild rodents embody behavioral plasticity and repertoires, illustrated by habituation and variation in behavioral traits, respectively. Results In this comparative study, we examined multiple behavioral responses of four rodent species in eastern Taiwan (three native species Mus caroli, Apodemus agrarius, Rattus losea, and one invasive, Rattus exulans) exposed to an unfamiliar microenvironment and novel cue from an allopatric predator, the leopard cat (Prionailurus bengalensis). All wild-caught animals were subjected to two consecutive nights of experimental trials in a laboratory setting. Behavioral responses to a novel situation during the first trial differed between species; smaller species investing more time in non-defensive behaviors compared to the larger species. More specifically, the smaller species M. caroli and A. agrarius allocated more time to exploration and foraging, whereas the larger rat species R. exulans and R. losea spent more time motionless or concealing. During the second trial, the addition of leopard cat cues did not elicit antipredator behaviors, but rather, rodents were found to exhibit increased non-defensive behaviors, specifically foraging efforts. Conclusions Our results suggest that these four species do largely follow a behavioral fast-slow continuum with the two smaller mice species demonstrating increased boldness in a novel context compared to the larger rat species. Also, the wild populations of rodents in eastern Taiwan may be naïve to leopard cats. Finally, the rodents in our study demonstrated habituation to the microenvironment, indicating they possess adaptive capacity.

To probe the mechanism of inhibition of several previously-published metallo-β-lactamase (MBL) inhibitors for the clinically-important MBL Verona integron-encoded metallo-β-lactamase 2 (VIM-2), equilibrium dialyses with metal analyses, native state electrospray ionization mass spectrometry (ESI-MS), and UV-Vis spectrophotometry were utilized. The mechanisms of inhibition were analyzed for ethylenediaminetetraacetic acid (EDTA); dipicolinic acid (DPA) and DPA analogs 6-(1H-tetrazol-5-yl)picolinic acid (1T5PA) and 4-(3-aminophenyl)pyridine-2,6-dicarboxylic acid (3AP-DPA); thiol-containing compounds, 2,3-dimercaprol, thiorphan, captopril, and tiopronin; and 5-(pyridine-3-sulfonamido)-1,3-thiazole-4-carboxylic acid (ANT-431). UV-Vis spectroscopy and native-state ESI-MS results showed the formation of ternary complexes between VIM-2 and 1T5PA, ANT-431, thiorphan, captopril, and tiopronin, while a metal stripping mechanism was shown with VIM-2 and EDTA and DPA. The same approaches were used to show the formation of a ternary complex between New Delhi Metallo-β-lactamase (NDM-1) and ANT-431. The studies presented herein show that most of the inhibitors utilize a similar mechanism of inhibition as previously reported for NDM-1. These studies also demonstrate that native mass spectrometry can be used to probe the mechanism of inhibition at lower enzyme/inhibitor concentrations than has previously been achieved.

Additional file 1: Figure S1. Monthly capture record of (a) adults; (b) juveniles; (c) recapture rates of all individuals; and (d) male/female composition (green/red) from May 2006 to August 2013. Figure S2. Sexual size dimorphism of Takydromus viridipunctatus.

Food and parasitism can have complex effects on small mammal reproduction. In this study, we tested the effects of sex, food, and parasitism on reproductive performance of the Taiwan field mouse (Apodemus semotus). In a field experiment, we increased food availability for a portion of the mice in the population by providing sorghum seeds to a set of food stations. We reduced parasite intensity of randomly chosen mice through ivermectin treatment. We determined the number and quality of offspring for the mice using paternity analysis. We quantified seed consumption with stable carbon isotope values of mouse plasma and parasite intensity with fecal egg counts of intestinal nematodes and cestodes (FEC). In a laboratory experiment, we reduced parasite intensity of randomly chosen mice through ivermectin treatment. We quantified their immune functions by total white blood cell count, percent granulocyte count, and percent lymphocyte count through hematological analyses. We measured the FEC and energy intake of the mice. From the field experiment, the number of offspring in A. semotus increased with increasing seed consumption. Due to the trade‐off between number and quality of offspring, the offspring quality decreased with increasing seed consumption for the females. The ivermectin treatment did not affect offspring number or quality. However, the FEC was positively correlated with number of offspring. In the laboratory experiment, the percent lymphocyte/granulocyte count changed with parasite intensity at low energy intake, which was relaxed at high energy intake. This study demonstrated positive effects of food availability and neutral effects of parasitism on A. semotus reproduction. However, the benefits of food availability for the females need to take into account the offspring number–quality trade‐off, and at high infection intensity, parasitism might negatively affect offspring quality for the males. We suggest that food availability could mediate the relationships between parasite intensity and immune responses.

This diary study provided the first classroom-based empirical test of the relations between student perceptions of high school science teachers’ various autonomy supporting and thwarting practices and students’ motivation and engagement on a daily basis over the course of an instructional unit. Perceived autonomy supporting practices were hypothesized to predict autonomous motivation and engagement outcomes, while perceived autonomy thwarting practices were hypothesized to predict controlled motivation and disaffection outcomes. In line with this prediction, multilevel modeling results based on regular reports of 208 high school students in 41 science classes across 6 weeks suggested that 4 perceived daily supports (choice provision, consideration for student preferences and interests, rationales for importance, and question opportunities) and 1 daily thwart (use of uninteresting activities) predicted changes in daily autonomous motivation and engagement. In contrast, changes in students’ daily controlled motivation and disaffection were predicted primarily by 3 perceived daily thwarts (controlling messages, suppression of student perspectives, and use of uninteresting activities). Results also suggested that practices interacted such that the perception of thwarts generally bolstered desirable daily relationships between perceived supports and students’ motivation and the perception of supports generally mitigated undesirable daily relationships between thwarts and motivation. Supplemental exploratory results suggested that the effects of choice and suppression of student perspectives may be heterogeneous and depend on the outcome and/or the presence of other practices. Implications of the findings are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved)