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1.
J Anim Ecol ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354661

RESUMO

Natural populations are composed of individuals that vary in their morphological traits, timing and interactions. The distribution of a trait can be described by several dimensions, or mathematical moments-mean, variance, skew and kurtosis. Shifts in the distribution of a trait across these moments in response to environmental variation can help to reveal which trait values are gained or lost, and consequently how trait filtering processes are altering populations. To examine the role and drivers of intraspecific variation within a trait filtering framework, we investigate variation in body size among five wild bumblebee species in the Colorado Rocky Mountains. First, we examine the relationships between environmental factors (climate and floral food resources) and body size distributions across bumblebee social castes to identify demographic responses to environmental variation. Next, we examine changes in the moments of trait distributions to reveal potential mechanisms behind intraspecific shifts in body size. Finally, we examine how intraspecific body size variation is related to diet breadth and phenology. We found that climate conditions have a strong effect on observed body size variation across all distributional moments, but the filtering mechanism varies by social caste. For example, with earlier spring snowmelt queens declined in mean size and became negatively skewed and more kurtotic. This suggests a skewed filter admitting a greater frequency of small individuals. With greater availability of floral food resources, queens increased in mean size, but workers and males decreased in size. Observed shifts in body size variation also correspond with variation in diet breadth and phenology. Populations with larger average body size were associated with more generalized foraging in workers of short-tongued species and increased specialization in longer-tongued workers. Altered phenological timing was associated with species- and caste-specific shifts in skew. Across an assemblage of wild bumblebees, we find complex patterns of trait variation that may not have been captured if we had simply considered mean and variance. The four-moment approach we employ here provides holistic insight into intraspecific trait variation, which may otherwise be overlooked and reveals potential underlying filtering processes driving such variation within populations.

2.
Ecol Evol ; 14(9): e70142, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39315298

RESUMO

Differential use of resources among bird species has been examined extensively in diet and nesting sites, but few studies have assessed this regarding avian nest materials. We assessed the structure and composition of nests in a group of co-existing passerine shrubland birds at a site in Massachusetts, USA. We found, measured, collected, and dissected nests, and then weighed nest materials in morphological groups (e.g., bark, twigs, feathers) to determine if our seven focal species were using different nest materials. Among species, we compared proportional material masses in complete nests, and also separately in the exterior, structural part of the nest and the interior, cup lining. We found that the proportional masses of all 17 material types that we examined in nests differed among species. The compositions of nests among all seven bird species were distinct in multivariate ordination space and only a few pairs of species had substantial niche overlap. Proportional masses of materials within discrete sections (exterior and interior) also varied among species. Although some differences in nest composition could be partially explained by bird species size, nest materials differed even within the three larger bodied species and within four smaller bodied species. Our study builds upon previous studies that have shown species-specificity in avian nest composition and supports the notion that birds using the same environment have distinct niches in relation to the materials placed in their nests. Niche partitioning due to interspecific competition could partially explain our findings, as certain materials are limited as resources, and searching for suitable nest materials is energetically costly. Additionally, other factors, such as partitioned nest sites, may have led to differential nest material use. We recommend further research to help elucidate underlying mechanisms of nest composition partitioning in birds and potentially other nest-building taxa.

3.
J Child Lang ; : 1-26, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39301833

RESUMO

In gaining word knowledge, children's semantic representations are initially imprecise before becoming gradually refined. We developed and tested a framework for a digital receptive vocabulary assessment that captured varied levels of representation as children learn words. At pre-test and post-test, children selected one of four images to match a word's meaning: a correct target, a conceptually-related foil, a thematically-related foil, and a phonologically-similar foil. We expected that selecting a conceptually related foil would indicate that the word is understood at a deeper level than selecting a phonologically similar foil. Indeed, selection of phonological foils decreased from pre- to post-test, while selection of more advanced thematic and conceptual foils increased. These results demonstrate that this assessment tool probed semantic knowledge that might be characterized as intermediate word knowledge. The current paper presents a novel and sensitive way to capture the incremental process of word learning. Applications for vocabulary interventions are discussed.

4.
Sci Total Environ ; 954: 176584, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39349195

RESUMO

As a recurrent climatic phenomenon in the context of climate change, extreme rainstorms induce vertical translocation of organic matter and increase moisture content in terrestrial ecosystems. However, it remains unclear whether heavy rainstorms can impact microbial communities in the deep biosphere by modulating organic matter input. In this study, we present findings on the different responses of bacterial and fungal communities in a subsurface cave to rainstorms and moisture variations through field surveys and microcosm experiments. During periods of rainstorms, the influx of dissolved organic matter (DOM) from soil overlying the cave into cave sediments significantly enhanced the correlation between core bacteria and environmental factors, particularly fluorescence spectral indices. The resource utilization of core bacteria was diminished, while the functional diversity of core fungi remained relatively unaltered. We also performed simulated experiments with restricted external DOM inputs, in which DOM content was observed to decrease and microbial diversity increase in response to artificially increased moisture content (MC). The niche breadth of core bacteria decreased and became more closely associated with DOM as the MC increased, while the niche breadth of core fungi remained predominantly unchanged. Compared to fungi, cave bacteria exhibited higher sensitivity towards variations in DOM. The core microbiome can efficiently utilize the available organic matter and participate in nitrogen- and sulfur-related metabolic processes. The study systematically revealed distinct microbial responses to rainstorm events, thereby providing valuable insights for future investigations into energy utilization within deep biospheres.

5.
J Evol Biol ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39291872

RESUMO

One of the most evident sources of phenotypic diversity within a population is colouration, as exemplified by colour polymorphism. This is relevant to a greater extent in animals with visually-biased sensory systems. There is substantial evidence suggesting that different colour morphs can access a broader range of habitats or niches, leading to larger geographic range sizes. However, this hypothesis has been tested in few lineages, comprising species where colour is likely to be involved in sexual selection. Furthermore, some available evidence considers geographical variation as polymorphism, thus limiting our comprehension of how sympatric colour polymorphism can influence a species' geographic range. Through an extensive systematic literature review and a comparative analysis, we examined the relationship between colour polymorphism and range size or niche breadth in web-building spiders. We identified 140 colour polymorphic spider species, belonging mainly to the families Araneidae and Theridiidae. We found no evidence that colour polymorphic species differ significantly from non-polymorphic species in terms of range size and niche breadth, after accounting for phylogenetic relationships and other covariates. However, we did observe that colour polymorphic species were more likely to be found on islands compared to non-polymorphic species. Overall, our results indicate that the association between colour polymorphism and geographic range size may not exist among web-building spiders, or be as pronounced as in other lineages. This suggests that the strength of the association between colour polymorphism and ecological success might depend on the ecological role that colouration plays in each clade.

6.
J Hum Evol ; 195: 103580, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39226621

RESUMO

Thermoregulation is argued to be an important factor influencing body breadth in hominins based on the relationship of surface area to body mass first proposed by Bergmann. Selection for a narrow thorax, and thus a narrow pelvis, increases body surface area relative to body mass, which could be beneficial in hot climates if it leads to a decrease in core body temperature. However, the relationship between pelvic breadth and thermoregulation in humans has not been established. Although previous work has shown that bi-iliac breadth is significantly positively associated with latitude in humans, we lack an understanding of whether this association is due to climate-related selection, neutral evolutionary processes, or other selective pressures. A missing piece of the puzzle is whether body breadth at the iliac blades is an important factor in thermoregulation. Here, we examine this in a mixed-sex sample of 28 adult runners who ran for one hour at 3.14 m s-1 in a variety of climatic conditions while their core body temperatures were measured using internal temperature sensors. The association of maximum core temperature with anthropometric and demographic variables such as age, sex, mass, body fat percentage, and bi-iliac breadth was analyzed using a linear mixed-effect model. Due to the small sample size, the model was also bootstrapped. We found that an increase in absolute bi-iliac breadth was significantly associated with an increase in maximum core temperature. Overall, this preliminary analysis suggests a link between variation in bi-iliac breadth and maximum core body temperature during running, but further investigation is needed.


Assuntos
Regulação da Temperatura Corporal , Temperatura Corporal , Humanos , Masculino , Feminino , Adulto , Regulação da Temperatura Corporal/fisiologia , Ílio/anatomia & histologia , Ílio/fisiologia , Adulto Jovem , Corrida/fisiologia , Pessoa de Meia-Idade
7.
Environ Sci Ecotechnol ; 22: 100478, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39280593

RESUMO

Urbanization is modifying aquatic ecosystems, with hydrodynamic and trophic variations altering biotic assemblages in rapidly expanding cities worldwide. Despite the fundamental bioenergetic role of food webs within these assemblages, their responding mechanism to the hydrodynamic and trophic variations remains largely unknown. Here we show that hydrodynamic and trophic loss, coupled with the weakening of cascade controls by key trophic guilds, leads to a significant decline in the structure, function and stability of macroinvertebrate food webs. Utilizing the allometric diet breadth model and biomass balance model, we established representative food webs for macroinvertebrate groups under varying hydrodynamic and trophic stresses. We found that such losses have reduced ∼75% trophic guild richness, ∼85% biomass flux, and ∼80% biomass storage. These reductions promote trophic guild specialization, further destabilizing food web, eroding interactive strength asymmetry, and diminishing the control of trophic guilds. Furthermore, macroinvertebrate food webs show divergent stability responses under similar stress levels, mainly driven by differences in the cascade controls exerted by key trophic guilds. Our results underscore the critical role of hydrodynamic and trophic variations in shaping urban aquatic ecosystems and highlight the significance of both external environmental revitalization and internal food web dynamics enhancement in restoring the ecological stability in urban settings.

8.
J Environ Manage ; 368: 122193, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39178793

RESUMO

As global warming and environmental degradation escalate, policymakers worldwide increasingly advocate for the development of green patents. However, there is ongoing debate regarding the effectiveness of green patents in actual pollution reduction. Some studies suggest that firms may engage in green patenting activities to align with government and market expectations rather than achieving substantive breakthroughs in pollution reduction. In light of this, it is crucial to examine the impact of green patents on pollution reduction. This study employs a PSM-DID model to analyze the impact of green patents on pollution emission intensity using plant-level data from Chinese industrial firms. The results demonstrate that with an average increase of 1% in the number of green patents, the industrial waste gas emission intensity and industrial wastewater discharge intensity decreased by 4.74% and 8.68%, respectively. Furthermore, pollution treatment facilities were found to be more effective than green patents during the sample period. On average, the contribution of waste gas treatment facilities and wastewater treatment facilities in pollution reduction is 3.33% and 9.79% higher than that of green patents. These findings suggest that firms should adopt a balanced approach when making decisions on pollution reduction. Further analysis shows that the pollution reduction effect of green patents is partly at the expense of the total factor productivity of firms. This trade-off highlights the need for policy interventions to support firms in integrating green technologies without compromising productivity. This study underscores the emphasizes of transitioning from end-of-pipe pollution control to green production processes to achieve sustainable development in China.


Assuntos
Indústrias , China , Poluição Ambiental/prevenção & controle , Resíduos Industriais , Patentes como Assunto , Águas Residuárias
9.
Hum Vaccin Immunother ; 20(1): 2388344, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-39165108

RESUMO

Monoclonal neutralizing antibodies (mAbs) are considered an important prophylactic against SARS-CoV-2 infection in at-risk populations and a strategy to counteract future sarbecovirus-induced disease. However, most mAbs isolated so far neutralize only a few sarbecovirus strains. Therefore, there is a growing interest in bispecific antibodies (bsAbs) which can simultaneously target different spike epitopes and thereby increase neutralizing breadth and prevent viral escape. Here, we generate and characterize a panel of 30 novel broadly reactive bsAbs using an efficient controlled Fab-arm exchange protocol. We specifically combine some of the broadest mAbs described so far, which target conserved epitopes on the receptor binding domain (RBD). Several bsAbs show superior cross-binding and neutralization compared to the parental mAbs and cocktails against sarbecoviruses from diverse clades, including recent SARS-CoV-2 variants. BsAbs which include mAb COVA2-02 are among the most potent and broad combinations. As a result, we study the unknown epitope of COVA2-02 and show that this mAb targets a distinct conserved region at the base of the RBD, which could be of interest when designing next-generation bsAb constructs to contribute to a better pandemic preparedness.


Assuntos
Anticorpos Biespecíficos , Anticorpos Neutralizantes , Anticorpos Antivirais , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Anticorpos Biespecíficos/imunologia , Humanos , SARS-CoV-2/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Neutralizantes/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Epitopos/imunologia , Testes de Neutralização , Animais , Anticorpos Monoclonais/imunologia
10.
Vaccines (Basel) ; 12(8)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39204019

RESUMO

The first vaccine against chikungunya virus (CHIKV) was recently licensed in the U.S., Europe, and Canada (brand IXCHIQ®, referred to as VLA1553). Other pathogenic alphaviruses co-circulate with CHIKV and major questions remain regarding the potential of IXCHIQ to confer cross-protection for populations that are exposed to them. Here, we characterized the cross-neutralizing antibody (nAb) responses against heterotypic CHIKV and additional arthritogenic alphaviruses in individuals at one month, six months, and one year post-IXCHIQ vaccination. We characterized nAbs against CHIKV strains LR2006, 181/25, and a 2021 isolate from Tocantins, Brazil, as well as O'nyong-nyong virus (ONNV), Mayaro virus (MAYV), and Ross River virus (RRV). IXCHIQ elicited 100% seroconversion to each virus, with the exception of RRV at 83.3% seroconversion of vaccinees, and cross-neutralizing antibody potency decreased with increasing genetic distance from CHIKV. We compared vaccinee responses to cross-nAbs elicited by natural CHIKV infection in individuals living in the endemic setting of Puerto Rico at 8-9 years post-infection. These data suggest that IXCHIQ efficiently and potently elicits cross-nAb breadth that extends to related alphaviruses in a manner similar to natural CHIKV infection, which may have important implications for individuals that are susceptible to alphavirus co-circulation in regions of potential vaccine rollout.

11.
Environ Microbiome ; 19(1): 57, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103916

RESUMO

BACKGROUND: Lichens are micro-ecosystems relying on diverse microorganisms for nutrient cycling, environmental adaptation, and structural support. We investigated the spatial-scale dependency of factors shaping the ecological processes that govern lichen-associated bacteria. We hypothesize that lichens function as island-like habitats hosting divergent microbiomes and promoting landscape gamma-diversity. Three microenvironments -thalli, substrates, and neighboring soils- were sampled from four geographically overlapping species of Peltigera cyanolichens, spanning three bioclimatic zones in the Chilean Patagonia, to determine how bacterial diversity, assembly processes, ecological drivers, interaction patterns, and niche breadth vary among Peltigera microenvironments on a broad geographical scale. RESULTS: The hosts' phylogeny, especially that of the cyanobiont, alongside climate as a secondary factor, impose a strong ecological filtering of bacterial communities within Peltigera thalli. This results in deterministically assembled, low diverse, and phylogenetically convergent yet structurally divergent bacterial communities. Host evolutionary and geographic distances accentuate the divergence in bacterial community composition of Peltigera thalli. Compared to soil and substrate, Peltigera thalli harbor specialized and locally adapted bacterial taxa, conforming sparse and weak ecological networks. CONCLUSIONS: The findings suggest that Petigera thalli create fragmented habitats that foster landscape bacterial gamma-diversity. This underscores the importance of preserving lichens for maintaining a potential reservoir of specialized bacteria.

12.
Sci Total Environ ; 951: 175494, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39153623

RESUMO

Soil microbial communities are major drivers of cycling of soil nutrients that sustain plant growth and productivity. Yet, a holistic understanding of the impact of abandoned agricultural land reclamation on the soil microbe is still poorly understood, especially for the microbial community assembly mechanisms. Here, we investigated the influence of reclamation on the relative importance of stochastic and deterministic processes in shaping microbial community assembly. After reclaiming abandoned cropland for corn and soybean cultivation, the fungal community assembly was shifted to stochastic processes, while bacterial communities remained predominantly influenced by stochastic processes. Our study revealed that reclamation did not significantly affect bacterial diversity, community niche breadth, and community similarity. In contrast, fungal communities exhibited lower alpha diversity, narrower niche breadths, greater niche overlap and higher community similarity in corn and soybean cultivation treatment in response to reclamation. Moreover, soil pH and soil available phosphorus were the most important environmental factors influencing fungal richness, niche breadths, community assembly processes, and community similarity. Together, the reclamation of abandoned cropland promoted the transformation of the fungal community assembly from deterministic process to a stochastic process, leading to decreased fungal diversity and broader ecological niche width, ultimately resulting in greater similarity among fungal communities. This finding provides insight into the varied responses of microbial diversity and ecological process to abandoned cropland reclamation, offering valuable guidance for the conservation and sustainable management of abandoned cropland in future land-use practices.


Assuntos
Agricultura , Fungos , Microbiologia do Solo , Processos Estocásticos , Agricultura/métodos , Micobioma , Solo/química , Microbiota
13.
Cureus ; 16(7): e63790, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39099952

RESUMO

Introduction Determination of gender can be highly accurate with a complete adult skeleton, but in scenarios like mass disasters, only fragmented bones might be available. In such cases, identifying gender relies significantly on which parts of the skeleton are found. The mandible is a notably distinct bone in the skull and can be key in determining gender, especially when the entire skull is not available. The mandibular features provide clues that can help forensic experts determine the gender of an individual. Aim of the study This preliminary study aimed to determine the gender of an individual using mandibular parameters such as coronoid ramus height, condylar ramus height, projective ramus, minimum ramus breadth, and maximum ramus breadth. The objectives of this study were to (i) determine the gender of an individual using various mandibular parameters, (ii) evaluate the effectiveness of these mandibular parameters in distinguishing between male and female individuals, and (iii) establish a reliable method for gender identification based on the measured mandibular parameters. Materials and methods Since it was a preliminary study, the sample size calculation was done using G*Power software (Version 3.1.9.4; Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany). The sample size was determined to guarantee a 95% statistical power at a significance level (alpha error probability) of 0.05. To ensure sufficient statistical power, a total of 100 samples were included, with a projected sample size of 92. A total of 100 samples, evenly split between 50 males and 50 females aged 20 to 30 years, were analyzed. Orthopantomograms (OPGs) showing pathologies, fractures, developmental disturbances of the mandible, and edentulous mandibles were excluded from the study. Statistical analysis was performed using SPSS for Windows, Version 16.0 (Released 2007; SPSS Inc., Chicago, IL, USA). Additionally, an accuracy test, analysis of variance (ANOVA), multiple regression, and discriminant analysis for gender were performed on individual data. Results In this study, five mandibular parameters were analyzed for gender such as coronoid ramus height, condylar ramus height, projective ramus, minimum ramus breadth, and maximum ramus breadth showed a positive correlation comparatively, and a novel formula was developed.  Conclusion According to the present study, panoramic radiography can be considered a valuable tool in sex determination (with an accuracy of 90%), and all parameters of the mandible exhibited sexual dimorphism, showing they are reliable parameters with a total accuracy of 90%. However, coronoid ramus height, projective ramus, and maximum ramus breadth played a significant role in identifying gender in this particular study.

14.
Ecol Lett ; 27(8): e14487, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39086139

RESUMO

The hypothesis that species' ranges are limited by interspecific competition has motivated decades of debate, but a general answer remains elusive. Here we test this hypothesis for lowland tropical birds by examining species' precipitation niche breadths. We focus on precipitation because it-not temperature-is the dominant climate variable that shapes the biota of the lowland tropics. We used 3.6 million fine-scale citizen science records from eBird to measure species' precipitation niche breadths in 19 different regions across the globe. Consistent with the predictions of the interspecific competition hypothesis, multiple lines of evidence show that species have narrower precipitation niches in regions with more species. This means species inhabit more specialized precipitation niches in species-rich regions. We predict this niche specialization should make tropical species in high diversity regions disproportionately vulnerable to changes in precipitation regimes; preliminary empirical evidence is consistent with this prediction.


Assuntos
Distribuição Animal , Aves , Chuva , Clima Tropical , Animais , Aves/fisiologia , Ecossistema , Comportamento Competitivo , Biodiversidade
15.
Macromol Rapid Commun ; : e2400198, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39150329

RESUMO

Statistical copolymers are commercially important because their properties can be tuned by comonomer selection and composition. Rubbery-state styrene (S)/n-butyl acrylate (nBA) copolymers have previously been reported to exhibit facile, autonomous self-healing over a narrow composition band (47/53 to 53/47 mol%). The need for a narrow composition band is explained by alternating comonomer sequences that accommodate interchain secondary bonding. It is hypothesized that copolymers that achieve interchain secondary bonding without alternating sequences can exhibit facile self-healing over a broad composition range. 2-ethylhexyl acrylate (EHA) is identified as yielding sequence-independent secondary bonding interactions. For these interactions it is tested experimentally by glass transition breadth in rubbery-state S/EHA copolymers, with S/n-hexyl acrylate (nHA) and S/nBA copolymers as controls. The n-alkyl acrylate random copolymers exhibit enhanced glass transition breadths over narrow composition bands that correspond to autonomous self-healing. In contrast, S/EHA copolymers exhibit much greater glass transition breadths than S/nHA and S/nBA copolymers at all compositions tested as well as self-healing of damage over a broad composition range with full tensile-property recovery, often in 3-10 h. Characterization of glass transition breadth may serve as a simple screening tool for identifying copolymers that exhibit broad-composition-range, facile, autonomous self-healing and contribute to polymer resilience and sustainability.

16.
Artigo em Inglês | MEDLINE | ID: mdl-39134921

RESUMO

Individuals' abilities to perform goal-directed spatial deployments of attention are distinguishable from their broader preferences for how they use spatial attention when circumstances do not compel a specific deployment strategy. Although these preferences are likely to play a major role in how we interact with the visual world during daily life, they remain relatively understudied. This exploratory study investigated two key questions about these preferences: firstly, are individuals consistent in their preferences for how they deploy their spatial attention when making shifts of attention versus adopting an attentional breadth? Secondly, which other factors are associated with these preferences? Across two experiments, we measured how participants preferred to deploy both attentional breadth (using an adapted Navon task) and eye movements (using a free-viewing task). We also measured participants' working memory capacities (Experiment 1), and their personalities and world beliefs (Experiment 2). In both experiments, there were consistent individual differences in preference for attentional breadth and eye movement characteristics, but these two kinds of preference were unrelated to each other. Working memory capacity was not linked to these preferences. Conversely, the personality trait of Openness to Experience robustly predicted two aspects of eye movement behavior preference, such that higher levels of Openness predicted smaller saccades and shorter scan paths. This suggests that personality dimensions may predict preferences for more absorbed engagement with visual information. However, it appears that individuals' preferences for shifts of attention during scene viewing do not necessarily relate to the breadth of attention they choose to adopt.

17.
Vaccines (Basel) ; 12(8)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39204008

RESUMO

PARVAX is a genetic vaccine platform based on an adeno-associated vector that has demonstrated to elicit potent, durable, and protective immunity in nonhuman primates (NHPs) after a single dose. Here, we assessed vaccine immunogenicity following a PARVAX prime-boost regimen against SARS-CoV-2. In mice, a low-dose prime followed by a higher-dose boost elicited potent neutralizing antibody responses and distinct cross-reactivity profiles, depending on the antigen used in the booster vaccine. However, the potent neutralizing anti-vector antibody responses developed in mice limited the dose that could be administered as a prime. We further explored the re-administration efficacy in NHPs primed with a SARS-CoV-2 Delta vaccine and boosted with an Omicron BA.1 vaccine at week 15, after the primary response peak antibody levels were reached. The boost elicited an increase in antibodies against several Omicron variants, but no increase was detected in the antibody titers for other variants. The anti-vector responses were low and showed some increased subsequent boosts but generally declined over time. The potent prime vaccination limited the detection of the boosting effect, and therefore, the effect of anti-vector immunity was not fully elucidated. These data show that PARVAX can be effectively re-administered and induce a novel antigenic response.

18.
Front Psychol ; 15: 1387624, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952823

RESUMO

Background: Workplace loneliness has become a prevalent experience among employees in organizations; however, there is limited empirical research on how leaders can address and mitigate this issue. Drawing upon self-determination theory and empowering leadership theory, this study examines the impact of empowering leadership on workplace loneliness by exploring the mediator of role breadth self-efficacy and the moderator of leader-member conversational quality. Methods: A time-lagged research design was used, collecting data through a two-wave online survey involving 531 employees in Chinese public sectors. The participants consisted of 321 males and 210 females, with an average age of 35 years (SD = 7.36). Results: Our findings indicate that empowering leadership positively influences employees' role breadth self-efficacy, reducing their workplace loneliness. Moreover, leader-member conversational quality strengthens this indirect effect, suggesting that empowering leadership is more effective in reducing workplace loneliness when leader-member conversational quality is high. Conclusion: This study expands and enriches research on the antecedents of workplace loneliness from the leadership approach, providing valuable insights for organizations to implement interventions that effectively alleviate employees' workplace loneliness.

19.
Genome Biol Evol ; 16(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38976568

RESUMO

Comparative analyses of gene birth-death dynamics have the potential to reveal gene families that played an important role in the evolution of morphological, behavioral, or physiological variation. Here, we used whole genomes of 30 species of butterflies and moths to identify gene birth-death dynamics among the Lepidoptera that are associated with specialist or generalist feeding strategies. Our work advances this field using a uniform set of annotated proteins for all genomes, investigating associations while correcting for phylogeny, and assessing all gene families rather than a priori subsets. We discovered that the sizes of several important gene families (e.g. those associated with pesticide resistance, xenobiotic detoxification, and/or protein digestion) are significantly correlated with diet breadth. We also found 22 gene families showing significant shifts in gene birth-death dynamics at the butterfly (Papilionoidea) crown node, the most notable of which was a family of pheromone receptors that underwent a contraction potentially linked with a shift to visual-based mate recognition. Our findings highlight the importance of uniform annotations, phylogenetic corrections, and unbiased gene family analyses in generating a list of candidate genes that warrant further exploration.


Assuntos
Borboletas , Genoma de Inseto , Filogenia , Animais , Borboletas/genética , Dieta , Mariposas/genética , Lepidópteros/genética , Evolução Molecular
20.
PeerJ ; 12: e17705, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39040933

RESUMO

The impact of temperature on reptile physiology has been examined through two main parameters: locomotor performance and metabolic rates. Among reptiles, different species may respond to environmental temperatures in distinct ways, depending on their thermal sensitivity. Such variation can be linked to the ecological lifestyle of the species and needs to be taken into consideration when assessing the thermal influence on physiology. This is particularly relevant for snakes, which are a very functionally diverse group. In this study, our aim was to analyze the thermal sensitivity of locomotor performance and resting metabolic rate (RMR) in three snake species from central Mexico (Crotalus polystictus, Conopsis lineata, and Thamnophis melanogaster), highlighting how it is influenced by their distinctive behavioral and ecological traits. We tested both physiological parameters in five thermal treatments: 15 °C, 25 °C, 30 °C, 33 °C, and 36 °C. Using the performance data, we developed thermal performance curves (TPCs) for each species and analyzed the RMR data using generalized linear mixed models. The optimal temperature for locomotion of C. polystictus falls near its critical thermal maximum, suggesting that it can maintain performance at high temperatures but with a narrow thermal safety margin. T. melanogaster exhibited the fastest swimming speeds and the highest mass-adjusted RMR. This aligns with our expectations since it is an active forager, a high energy demand mode. The three species have a wide performance breadth, which suggests that they are thermal generalists that can maintain performance over a wide interval of temperatures. This can be beneficial to C. lineata in its cold habitat, since such a characteristic has been found to allow some species to maintain adequate performance levels in suboptimal temperatures. RMR increased along with temperature, but the proportional surge was not uniform since thermal sensitivity measured through Q10 increased at the low and high thermal treatments. High Q10 at low temperatures could be an adaptation to maintain favorable performance in suboptimal temperatures, whereas high Q10 at high temperatures could facilitate physiological responses to heat stress. Overall, our results show different physiological adaptations of the three species to the environments they inhabit. Their different activity patterns and foraging habits are closely linked to these adaptations. Further studies of other populations with different climatic conditions would provide valuable information to complement our current understanding of the effect of environmental properties on snake physiology.


Assuntos
Temperatura , Animais , México , Metabolismo Basal/fisiologia , Locomoção/fisiologia , Crotalus/fisiologia , Especificidade da Espécie
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