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1.
Proc Natl Acad Sci U S A ; 119(2)2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34983877

RESUMO

Natural disasters impose huge uncertainty and loss to human lives and economic activities. Landslides are one disaster that has become more prevalent because of anthropogenic disturbances, such as land-cover changes, land degradation, and expansion of infrastructure. These are further exacerbated by more extreme precipitation due to climate change, which is predicted to trigger more landslides and threaten sustainable development in vulnerable regions. Although biodiversity conservation and development are often regarded as having a trade-off relationship, here we present a global analysis of the area with co-benefits, where conservation through expanding protection and reducing deforestation can not only benefit biodiversity but also reduce landslide risks to human society. High overlap exists between landslide susceptibility and areas of endemism for mammals, birds, and amphibians, which are mostly concentrated in mountain regions. We identified 247 mountain ranges as areas with high vulnerability, having both exceptional biodiversity and landslide risks, accounting for 25.8% of the global mountainous areas. Another 31 biodiverse mountains are classified as future vulnerable mountains as they face increasing landslide risks because of predicted climate change and deforestation. None of these 278 mountains reach the Aichi Target 11 of 17% coverage by protected areas. Of the 278 mountains, 52 need immediate actions because of high vulnerability, severe threats from future deforestation and precipitation extremes, low protection, and high-population density and anthropogenic activities. These actions include protected area expansion, forest conservation, and restoration where it could be a cost-effective way to reduce the risks of landslides.


Assuntos
Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Deslizamentos de Terra , Animais , Aves , Desastres , Ecossistema , Monitoramento Ambiental , Florestas , Humanos , Mamíferos , Densidade Demográfica , Medição de Risco
2.
J Neurosci ; 43(50): 8785-8800, 2023 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-37907257

RESUMO

Priority map theory is a leading framework for understanding how various aspects of stimulus displays and task demands guide visual attention. Per this theory, the visual system computes a priority map, which is a representation of visual space indexing the relative importance, or priority, of locations in the environment. Priority is computed based on both salience, defined based on image-computable properties; and relevance, defined by an individual's current goals, and is used to direct attention to the highest-priority locations for further processing. Computational theories suggest that priority maps identify salient locations based on individual feature dimensions (e.g., color, motion), which are integrated into an aggregate priority map. While widely accepted, a core assumption of this framework, the existence of independent feature dimension maps in visual cortex, remains untested. Here, we tested the hypothesis that retinotopic regions selective for specific feature dimensions (color or motion) in human cortex act as neural feature dimension maps, indexing salient locations based on their preferred feature. We used fMRI activation patterns to reconstruct spatial maps while male and female human participants viewed stimuli with salient regions defined by relative color or motion direction. Activation in reconstructed spatial maps was localized to the salient stimulus position in the display. Moreover, the strength of the stimulus representation was strongest in the ROI selective for the salience-defining feature. Together, these results suggest that feature-selective extrastriate visual regions highlight salient locations based on local feature contrast within their preferred feature dimensions, supporting their role as neural feature dimension maps.SIGNIFICANCE STATEMENT Identifying salient information is important for navigating the world. For example, it is critical to detect a quickly approaching car when crossing the street. Leading models of computer vision and visual search rely on compartmentalized salience computations based on individual features; however, there has been no direct empirical demonstration identifying neural regions as responsible for performing these dissociable operations. Here, we provide evidence of a critical double dissociation that neural activation patterns from color-selective regions prioritize the location of color-defined salience while minimally representing motion-defined salience, whereas motion-selective regions show the complementary result. These findings reveal that specialized cortical regions act as neural "feature dimension maps" that are used to index salient locations based on specific features to guide attention.


Assuntos
Mapeamento Encefálico , Córtex Visual , Humanos , Masculino , Feminino , Visão Ocular , Córtex Visual/fisiologia , Estimulação Luminosa/métodos , Percepção Visual/fisiologia
3.
Neuroimage ; 286: 120514, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38211706

RESUMO

Visual attention can be guided by statistical regularities in the environment, that people implicitly learn from past experiences (statistical learning, SL). Moreover, a perceptually salient element can automatically capture attention, gaining processing priority through a bottom-up attentional control mechanism. The aim of our study was to investigate the dynamics of SL and if it shapes attentional target selection additively with salience processing, or whether these mechanisms interact, e.g. one gates the other. In a visual search task, we therefore manipulated target frequency (high vs. low) across locations while, in some trials, the target was salient in terms of colour. Additionally, halfway through the experiment, the high-frequency location changed to the opposite hemifield. EEG activity was simultaneously recorded, with a specific interest in two markers related to target selection and post-selection processing, respectively: N2pc and SPCN. Our results revealed that both SL and saliency significantly enhanced behavioural performance, but also interacted with each other, with an attenuated saliency effect at the high-frequency target location, and a smaller SL effect for salient targets. Concerning processing dynamics, the benefit of salience processing was more evident during the early stage of target selection and processing, as indexed by a larger N2pc and early-SPCN, whereas SL modulated the underlying neural activity particularly later on, as revealed by larger late-SPCN. Furthermore, we showed that SL was rapidly acquired and adjusted when the spatial imbalance changed. Overall, our findings suggest that SL is flexible to changes and, combined with salience processing, jointly contributes to establishing attentional priority.


Assuntos
Eletroencefalografia , Percepção Visual , Humanos , Tempo de Reação
4.
Ecol Lett ; 27(9): e14509, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39354898

RESUMO

Understanding biotic interactions is a crucial goal in community ecology and species distribution modelling, and large strides have been made towards improving multivariate computational methods with the aim of quantifying biotic interactions and improving predictions of species occurrence. Yet, while considerable attention has been given to computational approaches and the interpretation of these quantitative tools, the importance of sampling design to reveal these biotic interactions has received little consideration. This study explores the influential role of priority effects, that is, the order of habitat colonisation, in shaping our ability to detect biotic interactions. Using a simple set of simulations, we demonstrate that commonly used cross-sectional co-occurrence data alone cannot be used to make reliable inferences on asymmetric biotic interactions, even if they perform well in predicting the occurrence of species. We then show how sampling designs that consider priority effects can recover the asymmetric effects that are lost when priority effects are ignored. Based on these findings, we urge for caution when drawing inferences on biotic interactions from cross-sectional binary co-occurrence data, and provide guidance on sampling designs that may provide the necessary data to tackle this longstanding challenge.


Assuntos
Ecossistema , Modelos Biológicos , Simulação por Computador
5.
Ecol Lett ; 27(3): e14406, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38491734

RESUMO

Rapid evolution in colonising populations can alter our ability to predict future range expansions. Recent theory suggests that the dynamics of replicate range expansions are less variable, and hence more predictable, with increased selection at the expanding range front. Here, we test whether selection from environmental gradients across space produces more consistent range expansion speeds, using the experimental evolution of replicate duckweed populations colonising landscapes with and without a temperature gradient. We found that the range expansion across a temperature gradient was slower on average, with range-front populations displaying higher population densities, and genetic signatures and trait changes consistent with directional selection. Despite this, we found that with a spatial gradient range expansion speed became more variable and less consistent among replicates over time. Our results therefore challenge current theory, highlighting that chance can still shape the genetic response to selection to influence our ability to predict range expansion speeds.


Assuntos
Evolução Biológica , Dinâmica Populacional , Temperatura , Densidade Demográfica , Fenótipo
6.
Ecol Lett ; 27(1): e14360, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38183675

RESUMO

Communities worldwide are losing multiple species at an unprecedented rate, but how communities reassemble after these losses is often an open question. It is well established that the order and timing of species arrival during community assembly shapes forthcoming community composition and function. Yet, whether the order and timing of species losses can lead to divergent community trajectories remains largely unexplored. Here, we propose a novel framework that sets testable hypotheses on the effects of the order and timing of species losses-inverse priority effects-and suggests its integration into the study of community assembly. We propose that the order and timing of species losses within a community can generate alternative reassembly trajectories, and suggest mechanisms that may underlie these inverse priority effects. To formalize these concepts quantitatively, we used a three-species Lotka-Volterra competition model, enabling to investigate conditions in which the order of species losses can lead to divergent reassembly trajectories. The inverse priority effects framework proposed here promotes the systematic study of the dynamics of species losses from ecological communities, ultimately aimed to better understand community reassembly and guide management decisions in light of rapid global change.


Assuntos
Biota , Ecossistema
7.
Emerg Infect Dis ; 30(7): 1326-1334, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38916545

RESUMO

COVID-19 vaccination was launched in March 2021 in Uganda and initially prioritized persons >50 years of age, persons with underlying conditions, healthcare workers, teachers, and security forces. However, uptake remained low 5 months after the program launch. Makerere University's Infectious Diseases Institute supported Uganda's Ministry of Health in optimizing COVID-19 vaccination uptake models by using point-of-care, place of worship, and place of work engagement and the Social Assistance Grant for Empowerment model in 47 of 135 districts in Uganda, where we trained influencers to support mobilization for vaccination outreach under each model. During July-December, vaccination rates increased significantly in targeted regions, from 92% to 130% for healthcare workers, 40% to 90% for teachers, 25% to 33% for security personnel, 6% to 15% for persons >50 years of age, and 6% to 11% for persons with underlying conditions. Our approach could be adopted in other targeted vaccination campaigns for future pandemics.


Assuntos
Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , Uganda/epidemiologia , COVID-19/prevenção & controle , COVID-19/epidemiologia , Vacinas contra COVID-19/administração & dosagem , SARS-CoV-2/imunologia , Pandemias/prevenção & controle , Pessoa de Meia-Idade , Vacinação , Adulto , Pessoal de Saúde , Programas de Imunização , Masculino , Feminino
8.
Breast Cancer Res Treat ; 208(1): 215-222, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38914917

RESUMO

PURPOSE: To use robust consensus methods with individuals with lived breast cancer experience to agree the top 10 research priorities to improve information and support for patients undergoing breast cancer surgery in the UK. METHODS: Research uncertainties related to information and support for breast cancer surgery submitted by patients and carers were analysed thematically to generate summary questions for inclusion in an online Delphi survey. Individuals with lived breast cancer experience completed two Delphi rounds including feedback in which they selected their top 10 research priorities from the list provided. The most highly ranked priorities from the survey were discussed at an in-person prioritisation workshop at which the final top 10 was agreed. RESULTS: The 543 uncertainties submitted by 156 patients/carers were categorised into 63 summary questions for inclusion in the Delphi survey. Of the 237 individuals completing Round 1, 190 (80.2%) participated in Round 2. The top 25 survey questions were carried forward for discussion at the in-person prioritisation workshop at which 17 participants from across the UK agreed the final top 10 research priorities. Key themes included ensuring patients were fully informed about all treatment options and given balanced, tailored information to support informed decision-making and empower their recovery. Equity of access to treatments including contralateral mastectomy for symmetry was also considered a research priority. CONCLUSION: This process has identified the top 10 research priorities to improve information and support for patients undergoing breast cancer surgery. Work is now needed to develop studies to address these important questions.


Assuntos
Neoplasias da Mama , Técnica Delphi , Mastectomia , Humanos , Neoplasias da Mama/cirurgia , Feminino , Reino Unido , Inquéritos e Questionários , Pessoa de Meia-Idade , Adulto , Assistência Centrada no Paciente , Pesquisa , Educação de Pacientes como Assunto/métodos , Idoso , Tomada de Decisões
9.
Small ; : e2405362, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39263784

RESUMO

It is urgent to develop efficient recycling methods for spent LiFePO4 cathodes to cope with the upcoming peak of power battery retirement. Compared with the traditional metallurgical recovery methods that lack satisfactory economic and environmental benefits, the direct regeneration seems to be a promising option at present. However, a simple direct lithium replenishment cannot effectively repair and regenerate the cathodes due to the serious structural damage of the spent LiFePO4. Herein, the spent LiFePO4 cathodes are directly regenerated by a thiourea-assisted solid-phase sintering process. The density functional theory calculation indicates that thiourea has a targeted repair effect on the antisite defects and inactive FePO4 phase in the spent cathode due to the associative priority of amino group (─NH2) in thiourea with Fe ions: Fe3+─N > Fe2+─N. Meanwhile, the pyrolysis products of thiourea can also create an optimal reducing atmosphere and inhibit the agglomeration of particles in the high temperature restoration process. The regenerated LiFePO4 exhibits an excellent electrochemical performance, which is comparable to that of commercial LiFePO4. This targeted restoration has improved the efficiency of direct regeneration, which is expected to achieve large-scale recycling of spent LiFePO4.

10.
Proc Biol Sci ; 291(2029): 20240915, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39191282

RESUMO

A pathogen arriving on a host typically encounters a diverse community of microbes that can shape priority effects, other within-host interactions and infection outcomes. In plants, environmental nutrients can drive trade-offs between host growth and defence and can mediate interactions between co-infecting pathogens. Nutrients may thus alter the outcome of pathogen priority effects for the host, but this possibility has received little experimental investigation. To disentangle the relationship between nutrient availability and co-infection dynamics, we factorially manipulated the nutrient availability and order of arrival of two foliar fungal pathogens (Rhizoctonia solani and Colletotrichum cereale) on the grass tall fescue (Lolium arundinaceum) and tracked disease outcomes. Nutrient addition did not influence infection rates, infection severity or plant biomass. Colletotrichum cereale facilitated R. solani, increasing its infection rate regardless of their order of inoculation. Additionally, simultaneous and C. cereale-first inoculations decreased plant growth and-in plants that did not receive nutrient addition-increased leaf nitrogen concentrations compared to uninoculated plants. These effects were partially, but not completely, explained by the duration and severity of pathogen infections. This study highlights the importance of understanding the intricate associations between the order of pathogen arrival, host nutrient availability and host defence to better predict infection outcomes.


Assuntos
Colletotrichum , Lolium , Nutrientes , Doenças das Plantas , Doenças das Plantas/microbiologia , Colletotrichum/fisiologia , Nutrientes/metabolismo , Lolium/microbiologia , Rhizoctonia/fisiologia , Coinfecção/microbiologia , Interações Hospedeiro-Patógeno , Folhas de Planta/microbiologia , Nitrogênio/metabolismo
11.
Appl Environ Microbiol ; 90(6): e0061924, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38757977

RESUMO

Host-associated microbial communities, like other ecological communities, may be impacted by the colonization order of taxa through priority effects. Developing embryos and their associated microbiomes are subject to stochasticity during colonization by bacteria. For amphibian embryos, often developing externally in bacteria-rich environments, this stochasticity may be particularly impactful. For example, the amphibian microbiome can mitigate lethal outcomes from disease for their hosts; however, this may depend on microbiome composition. Here, we examined the assembly of the bacterial community in spring peeper (Pseudacris crucifer) embryos and tadpoles. First, we reared embryos from identified mating pairs in either lab or field environments to examine the relative impact of environment and parentage on embryo and tadpole bacterial communities. Second, we experimentally inoculated embryos to determine if priority effects (i) could be used to increase the relative abundance of Janthinobacterium lividum, an amphibian-associated bacteria capable of preventing fungal infection, and (ii) would lead to observed differences in the relative abundances of two closely related bacteria from the genus Pseudomonas. Using 16S rRNA gene amplicon sequencing, we observed differences in community composition based on rearing location and parentage in embryos and tadpoles. In the inoculation experiment, we found that priority inoculation could increase the relative abundance of J. lividum, but did not find that either Pseudomonas isolate was able to prevent colonization by the other when given priority. These results highlight the importance of environmental source pools and parentage in determining microbiome composition, while also providing novel methods for the administration of a known amphibian probiotic. IMPORTANCE: Harnessing the functions of host-associated bacteria is a promising mechanism for managing disease outcomes across different host species. In the case of amphibians, certain frog-associated bacteria can mitigate lethal outcomes of infection by the fungal pathogen Batrachochytrium dendrobatidis. Successful probiotic applications require knowledge of community assembly and an understanding of the ecological mechanisms that structure these symbiotic bacterial communities. In our study, we show the importance of environment and parentage in determining bacterial community composition and that community composition can be influenced by priority effects. Further, we provide support for the use of bacterial priority effects as a mechanism to increase the relative abundance of target probiotic taxa in a developing host. While our results show that priority effects are not universally effective across all host-associated bacteria, our ability to increase the relative abundance of specific probiotic taxa may enhance conservation strategies that rely on captive rearing of endangered vertebrates.


Assuntos
Anuros , Larva , Microbiota , Probióticos , RNA Ribossômico 16S , Animais , Larva/microbiologia , Larva/crescimento & desenvolvimento , Anuros/microbiologia , Probióticos/administração & dosagem , Probióticos/farmacologia , RNA Ribossômico 16S/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética , Oxalobacteraceae/fisiologia , Pseudomonas/fisiologia , Embrião não Mamífero/microbiologia
12.
Appl Environ Microbiol ; : e0081824, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39291984

RESUMO

Specialized host-microbe symbioses are ecological communities, whose composition is shaped by various processes. Microbial community assembly in these symbioses is determined in part by interactions between taxa that colonize ecological niches available within habitat patches. The outcomes of these interactions, and by extension the trajectory of community assembly, can display priority effects-dependency on the order in which taxa first occupy these niches. The underlying mechanisms of these phenomena vary from system to system and are often not well resolved. Here, we characterize priority effects in colonization of the squash bug (Anasa tristis) by bacterial symbionts from the genus Caballeronia, using pairs of strains that are known to strongly compete during host colonization, as well as strains that are isogenic and thus functionally identical. By introducing symbiont strains into individual bugs in a sequential manner, we show that within-host populations established by the first colonist are extremely resistant to invasion, regardless of strain identity and competitive interactions. By knocking down the population of an initial colonist with antibiotics, we further show that colonization success by the second symbiont is still diminished even when space in the symbiotic organ is available and ostensibly accessible for colonization. We speculate that resident symbionts exclude subsequent infections by manipulating the host environment, partially but not exclusively by eliciting tissue remodeling of the symbiont organ. IMPORTANCE: Host-associated microbial communities underpin critical ecosystem processes and human health, and their ability to do so is determined in turn by the various processes that shape their composition. While selection deterministically acts on competing genotypes and species during community assembly, the manner by which selection determines the trajectory of community assembly can differ depending on the sequence by which taxa are established within that community. We document this phenomenon, known as a priority effect, during experimental colonization of a North American insect pest, the squash bug Anasa tristis, by its betaproteobacterial symbionts in the genus Caballeronia. Our study demonstrates how stark, strain-level variation can emerge in specialized host-microbe symbioses simply through differences in the order by which strains colonize the host. Understanding the mechanistic drivers of community structure in host-associated microbiomes can highlight both pitfalls and opportunities for the engineering of these communities and their constituent taxa for societal benefit.

13.
J Pediatr ; 275: 114211, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39059716

RESUMO

OBJECTIVE: To determine the clinical benefit of drugs that earned or redeemed rare pediatric disease priority review vouchers (PRVs) from 2017 through 2023, and the revenues generated by such drugs. STUDY DESIGN: In this cohort study, Federal Register documents, publicly available health technology agency (HTA) assessments, and financial filings were used to identify drugs that were issued or redeemed using a rare pediatric disease PRV from 2017 through 2023, and to assess their added therapeutic benefit and drug-specific global revenues. RESULTS: Among the 36 drugs whose approval resulted in issuance of a rare pediatric PRV, therapeutic benefit ratings were available for 17 (47%), with 9 (53%) rated as high by at least 1 organization. Mean annual global revenues were $363 million (year 1), $621 million (year 2), and $850 million (year 3). The median annual list price for drugs issued a voucher was $788,705. Vouchers were then redeemed for 15 different drugs; out of 13 drugs with therapeutic benefit ratings, 4 (31%) were high value. CONCLUSIONS: Drugs that treat rare pediatric diseases generate similar revenues compared with other brand drugs, and drugs with high therapeutic benefit tend to generate more revenue than those with low therapeutic benefit. Drugs that earned the rare pediatric disease PRV for their manufacturer generate significant revenues and the voucher may not be necessary to incentivize drug development in the rare pediatric disease space.

14.
New Phytol ; 241(1): 444-460, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37292019

RESUMO

Ectomycorrhizal (EcM) symbiosis, a ubiquitous plant-fungus interaction in forests, evolved in parallel in fungi. Why the evolution of EcM fungi did not necessarily increase ecological opportunities for explosive diversification remains unclear. This study aimed to reveal the driving mechanism of the evolutionary diversification in the fungal class Agaricomycetes, specifically by testing whether the evolution of EcM symbiosis in the Late Cretaceous increased ecological opportunities. The historical character transitions of trophic state and fruitbody form were estimated based on phylogenies inferred from fragments of 89 single-copy genes. Moreover, five analyses were used to estimate the net diversification rates (speciation rate minus extinction rate). The results indicate that the unidirectional evolution of EcM symbiosis occurred 27 times, ranging in date from the Early Triassic to the Early Paleogene. The increased diversification rates appeared to occur intensively at the stem of EcM fungal clades diverging in the Late Cretaceous, coinciding with the rapid diversification of EcM angiosperms. By contrast, the evolution of fruitbody form was not strongly linked with the increased diversification rates. These findings suggest that the evolution of EcM symbiosis in the Late Cretaceous, supposedly with coevolving EcM angiosperms, was the key drive of the explosive diversification in Agaricomycetes.


Assuntos
Basidiomycota , Micorrizas , Micorrizas/genética , Simbiose , Evolução Biológica , Basidiomycota/genética , Filogenia
15.
BMC Cancer ; 24(1): 962, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107697

RESUMO

BACKGROUND: Typically, researchers and clinicians determine the agenda in sarcoma research. However, patient involvement can have a meaningful impact on research. Therefore, the Patient-Powered Research Network (PPRN) of the Sarcoma Patient Advocacy Global Network (SPAGN) set up a Priority Setting Partnership (PSP). The primary objective of this partnership is to identify priorities for research and patient advocacy topics. METHODS: In the first phase of this PSP, including 264 sarcoma patients and carers from all over the world, 23 research topics regarding sarcomas and 15 patient advocacy topics were identified using an online survey. In the second phase, participants were asked to fill in a top five and a top three of research and patient advocacy topics, respectively. Additionally, sociodemographic characteristics and sarcoma characteristics were collected. Social media channels, local national patient advocacy groups and the SPAGN website were used to distribute the survey. RESULTS: In total, 671 patients (75%) and carers (25%) participated in this survey. The five highest ranked research topics were related to causes of sarcoma (43%), prognosis and risk of recurrence (40%), specific subtypes of sarcoma (33%), the role of immunotherapy, targeted therapy and combined therapy (30%), and hereditary aspects (30%). The three highest ranked patient advocacy topics were improving the diagnostic process of sarcoma (39%), access to tumor DNA analysis (37%) and establishing an international sarcoma registry (37%). CONCLUSIONS: This sarcoma PSP has identified priorities for research and patient advocacy, offering guidance for researchers, assisting funding agencies with assessing project relevance and empowering patient advocates to represent the needs of patients and carers.


Assuntos
Cuidadores , Defesa do Paciente , Sarcoma , Humanos , Sarcoma/terapia , Feminino , Masculino , Cuidadores/psicologia , Pessoa de Meia-Idade , Adulto , Inquéritos e Questionários , Pesquisa Biomédica , Idoso , Participação do Paciente , Adulto Jovem
16.
Theor Popul Biol ; 160: 1-13, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39182695

RESUMO

Settlement is a critical transition in the life history of reef fish, and the timing of this event can have a strong effect on fitness. Key factors that influence settlement timing are predictable lunar cyclic variation in tidal currents, moonlight, and nocturnal predation risk as larvae transition from pelagic to benthic environments. However, populations typically display wide variation in the arrival of settlers over the lunar cycle. This variation is often hypothesized to result from unpredictable conditions in the pelagic environment and bet-hedging by spawning adults. Here, we consider the hypothesis that the timing of spawning and settlement is a strategic response to post-settlement competition. We use a game theoretic model to predict spawning and settlement distributions when fish face a tradeoff between minimizing density-independent predation risk while crossing the reef crest vs. avoiding high competitor density on settlement habitat. In general, we expect competition to spread spawning over time such that settlement is distributed around the lunar phase with the lowest predation risk, similar to an ideal free distribution in which competition spreads competitors across space. We examine the effects of overcompensating density dependence, age-dependent competition, and competition among daily settler cohorts. Our model predicts that even in the absence of stochastic variation in the larval environment, competition can result in qualitative divergence between spawning and settlement distributions. Furthermore, we show that if competitive strength increases with settler age, competition results in covariation between settler age and settlement date, with older larvae settling when predation risk is minimal. We predict that competition between daily cohorts delays peak settlement, with priority effects potentially selecting for a multimodal settlement distribution.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38180015

RESUMO

The naming of prokaryotes is governed by the International Code of Nomenclature of Prokaryotes (ICNP) and partially by the International Code of Nomenclature for Algae, Fungi and Plants (ICN). Such codes must be able to determine names of taxa in a universal and unambiguous manner, thus serving as a common language across different fields and activities. This unity is undermined when a new code of nomenclature emerges that overlaps in scope with an established, time-tested code and uses the same format of names but assigns different nomenclatural status values to the names. The resulting nomenclatural confusion is not beneficial to the wider scientific community. Such ambiguity is expected to result from the establishment of the 'Code of Nomenclature of Prokaryotes Described from DNA Sequence Data' ('SeqCode'), which is in general and specific conflict with the ICNP and the ICN. Shortcomings in the interpretation of the ICNP may have exacerbated the incompatibility between the codes. It is reiterated as to why proposals to accept sequences as nomenclatural types of species and subspecies with validly published names, now implemented in the SeqCode, have not been implemented by the International Committee on Systematics of Prokaryotes (ICSP), which oversees the ICNP. The absence of certain regulations from the ICNP for the naming of as yet uncultivated prokaryotes is an acceptable scientific argument, although it does not justify the establishment of a separate code. Moreover, the proposals rejected by the ICSP are unnecessary to adequately regulate the naming of uncultivated prokaryotes. To provide a better service to the wider scientific community, an alternative proposal to emend the ICNP is presented, which would result in Candidatus names being regulated analogously to validly published names. This proposal is fully consistent with previous ICSP decisions, preserves the essential unity of nomenclature and avoids the expected nomenclatural confusion.


Assuntos
Ácidos Graxos , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química
18.
Ann Behav Med ; 58(2): 92-99, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-37874734

RESUMO

BACKGROUND AND PURPOSE: The present research tests whether intention strength moderates intention-health behavior relations and the extent to which this is accounted for by the moderating effects of intention stability, goal priority, and goal conflict. METHODS: In a prospective multi-behavior study, a representative sample of UK adults (N = 503) completed measures of past behavior, intention, intention strength, goal priority, and goal conflict in relation to eight Covid-19 protection behaviors at time 1. Intention and self-reported behavior were assessed at time 2 (2 months later). Intention stability was assessed over 2 months. RESULTS: Intention strength was a significant moderator of the intention-behavior relationship (controlling for past behavior). Controlling for the moderating effects of intention stability attenuated the moderating effect of intention strength, while also controlling for the moderating effects of goal priority and goal conflict reduced the moderating effects of intention strength to nonsignificance. CONCLUSIONS: The present findings indicate that intention strength is a significant moderator of the intention-health behavior relationship. They also suggest that the moderating effect of intention strength is explained by effects on intention stability, goal priority, and goal conflict. Tests of interventions to manipulate intention strength as a means to strengthen intention stability and intention-behavior relations are warranted.


Predictors of engaging in eight Covid-19 protection behaviors (e.g., wearing face coverings, social distancing) were examined in a representative sample of adults in the UK in November 2021. Intentions to engage in these behaviors (e.g., "I will try to wear a face covering in public places in the next two months") were a strong predictor of self-reported engagement 2 months later, even when taking account of people's past behavior. Importantly, people's intentions were more predictive of behavior when intentions were judged to be strong (e.g., important, based on a lot of thought). Further analyses revealed that the enhanced effect of strong intentions on behavior was due to strong intentions being more stable over time, and being given greater priority over, and not conflicting with, other goals. Increasing the strength of people's intentions may be a useful and novel way to increase performance of health-protection behaviors.


Assuntos
COVID-19 , Intenção , Adulto , Humanos , Estudos Prospectivos , COVID-19/prevenção & controle , Comportamentos Relacionados com a Saúde , Motivação
19.
AIDS Behav ; 28(6): 2015-2022, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38526637

RESUMO

Current international HIV testing guidelines recommend that HIV negative persons from HIV priority groups complete repeat screening every 3-6 months; local guidelines in our jurisdiction recommend that such retesting should occur every 3 months. Such an approach allows for timely HIV diagnosis and linkage to care - and aligns with the UNAIDS 95-95-95 targets to have 95% of undiagnosed persons be aware of their HIV status. To meet these aims, new approaches to HIV testing have been developed, including our HIV self-testing initiative, GetaKit.ca, which uses an online screening algorithm to determine eligibility and has built in pathways for re-test reminders, linkage HIV prevention care, and rapid follow-up for positive test results. To understand self-testing frequency in relation to our local recommendations for resting every 3 months, we evaluated data from participants who ordered repeat HIV self-tests through GetaKit.ca. Descriptive analyses were performed on participant characteristics and chi-square tests were performed on aggregated participant risk data. During the study period, 5235 HIV self-tests were distributed to 3627 participants, of whom, 26% ordered more than once and 27% belonged to an HIV priority population. Participants who retested were more likely to have been white, male, and part of an HIV priority population; they were also more likely to have completed prior STI or HIV testing or had a prior STI diagnosis, compared to those who did not. We identified 16 new HIV diagnoses, 2 of which were among repeat testers. Our results suggest that HIV self-testing can be useful to help meet UNAIDS targets to identify undiagnosed infections; however, such efforts are less likely to be successful without adequate linkage to follow-up services, including HIV treatment and prevention care.


Assuntos
Infecções por HIV , Teste de HIV , Programas de Rastreamento , Autoteste , Humanos , Masculino , Feminino , Adulto , Infecções por HIV/diagnóstico , Pessoa de Meia-Idade , Programas de Rastreamento/métodos , Teste de HIV/estatística & dados numéricos , Teste de HIV/métodos , Adulto Jovem , Adolescente , Algoritmos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos
20.
Environ Sci Technol ; 58(32): 14506-14517, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39087809

RESUMO

With the development of large numbers of novel organophosphate esters (OPEs) alternatives, it is imperative to screen and identify those with high priority. In this study, surface water, biofilms, and freshwater snails were collected from the flow-in rivers of Taihu Lake Basin, China. Screened by target, suspect, and nontarget analysis, 11 traditional and 14 novel OPEs were identified, of which 5 OPEs were first discovered in Taihu Lake Basin. The OPE concentrations in surface water ranged from 196 to 2568 ng/L, with the primary homologue tris(2,4-ditert-butylphenyl) phosphate (TDtBPP) being newly identified, which was likely derived from the transformation of tris(2,4-ditert-butylphenyl) phosphite. The majority of the newly identified OPEs displayed substantially higher bioaccumulation and biomagnification potentials in the biofilm-snail food chain than the traditional ones. Quantitative structure-property relationship models revealed both hydrophobicity and polarity influenced the bioaccumulation and biomagnification of the OPEs, while electrostatic attraction also had a contribution to the bioaccumulation in the biofilm. TDtBPP was determined as the utmost priority by toxicological priority index scheme, which integrated concentration, bioaccumulation, biomagnification, acute toxicity, and endocrine disrupting potential of the identified OPEs. These findings provide novel insights into the behaviors of OPEs and scientific bases for better management of high-risk pollutants in aquatic ecosystem.


Assuntos
Ésteres , Organofosfatos , Poluentes Químicos da Água , Relação Quantitativa Estrutura-Atividade , Animais , Monitoramento Ambiental , China , Caramujos
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