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2.
Proc Natl Acad Sci U S A ; 121(17): e2318596121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621142

RESUMO

While there is increasing recognition that social processes in cities like gentrification have ecological consequences, we lack nuanced understanding of the ways gentrification affects urban biodiversity. We analyzed a large camera trap dataset of mammals (>500 g) to evaluate how gentrification impacts species richness and community composition across 23 US cities. After controlling for the negative effect of impervious cover, gentrified parts of cities had the highest mammal species richness. Change in community composition was associated with gentrification in a few cities, which were mostly located along the West Coast. At the species level, roughly half (11 of 21 mammals) had higher occupancy in gentrified parts of a city, especially when impervious cover was low. Our results indicate that the impacts of gentrification extend to nonhuman animals, which provides further evidence that some aspects of nature in cities, such as wildlife, are chronically inaccessible to marginalized human populations.


Assuntos
Biodiversidade , Segregação Residencial , Animais , Humanos , Cidades , Mamíferos , Animais Selvagens , Ecossistema
3.
J Am Soc Mass Spectrom ; 35(3): 498-507, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38374644

RESUMO

Native ion mobility-mass spectrometry (IM-MS) typically introduces protein ions into the gas phase through nano-electrospray ionization (nESI). Many nESI setups have mobile stages for tuning the ion signal and extent of co-solute and salt adduction. However, tuning the position of the emitter capillary in nESI can have unintended downstream consequences for collision-induced unfolding or collision-induced dissociation (CIU/D) experiments. Here, we show that relatively small variations in the nESI emitter position can shift the midpoint (commonly called the "CID50" or "CIU50") potential of CID breakdown curves and CIU transitions by as much as 8 V on commercial instruments. A spatial "map" of the shift in CID50 for the loss of heme from holomyoglobin onto the emitter position on a Waters Synapt G2-Si mass spectrometer shows that emitter positions closer to the instrument inlet can result in significantly greater in-source activation, whereas different effects are found on an Agilent 6545XT instrument for the ions studied. A similar effect is observed for CID of the singly protonated leucine enkephalin peptide and Shiga toxin 1 subunit B homopentamer on the Waters Synapt G2-Si instrument. In-source activation effects on a Waters Synapt G2-Si are also investigated by examining the RMSD between CIU fingerprints acquired at different emitter positions and the shifts in CIU50 for structural transitions of bovine serum albumin and NIST monoclonal antibody.


Assuntos
Peptídeos , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Peptídeos/química , Íons , Soroalbumina Bovina
4.
J Chem Phys ; 159(21)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38047505

RESUMO

The fewest switches surface hopping (FSSH) method proposed by Tully in 1990 [Tully, J. Chem. Phys. 93, 1061 (1990)]-along with its many later variations-forms the basis for most practical simulations of molecular dynamics with electronic transitions in realistic systems. Despite its popularity, a rigorous formal derivation of the algorithm has yet to be achieved. In this paper, we derive the energy-conserving momentum jumps employed by FSSH from the perspective of quantum trajectory surface hopping (QTSH) [Martens, J. Phys. Chem. A 123, 1110 (2019)]. In the limit of localized nonadiabatic transitions, simple mathematical and physical arguments allow the FSSH algorithm to be derived from first principles. For general processes, the quantum forces characterizing the QTSH method provide accurate results for nonadiabatic dynamics with rigorous energy conservation, at the ensemble level, within the consistency of the underlying stochastic surface hopping without resorting to the artificial momentum rescaling of FSSH.

5.
J Chem Phys ; 159(20)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37991156

RESUMO

In this paper, we investigate the time evolution of quantum coherence-the off-diagonal elements of the density matrix of a multistate quantum system-from the perspective of the Wigner-Moyal formalism. This approach provides an exact phase space representation of quantum mechanics. We consider the coherent evolution of nuclear wavepackets in a molecule with two electronic states. For harmonic potentials, the problem is analytically soluble for both a fully quantum mechanical description and a semiclassical description. We highlight the serious deficiencies of the semiclassical treatment of coherence for general systems and illustrate how even qualitative accuracy requires higher order terms in the Moyal expansion to be included. The model provides an experimentally relevant example of a molecular Schrödinger's cat state. The alive and dead cats of the exact two-state quantum evolution collapse into a "zombie" cat in the semiclassical limit-an averaged behavior, neither alive nor dead, leading to significant errors. The inclusion of the Moyal correction restores a faithful simultaneously alive and dead representation of the cat that is experimentally observable.

6.
Nat Ecol Evol ; 7(10): 1654-1666, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37667002

RESUMO

Human-driven environmental changes shape ecological communities from local to global scales. Within cities, landscape-scale patterns and processes and species characteristics generally drive local-scale wildlife diversity. However, cities differ in their structure, species pools, geographies and histories, calling into question the extent to which these drivers of wildlife diversity are predictive at continental scales. In partnership with the Urban Wildlife Information Network, we used occurrence data from 725 sites located across 20 North American cities and a multi-city, multi-species occupancy modelling approach to evaluate the effects of ecoregional characteristics and mammal species traits on the urbanization-diversity relationship. Among 37 native terrestrial mammal species, regional environmental characteristics and species traits influenced within-city effects of urbanization on species occupancy and community composition. Species occupancy and diversity were most negatively related to urbanization in the warmer, less vegetated cities. Additionally, larger-bodied species were most negatively impacted by urbanization across North America. Our results suggest that shifting climate conditions could worsen the effects of urbanization on native wildlife communities, such that conservation strategies should seek to mitigate the combined effects of a warming and urbanizing world.

7.
Ecology ; 104(7): e4055, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37074821

RESUMO

Identifying drivers of urban association in wildlife is a central challenge in conservation biology. Traits facilitating access to novel resources and avoiding humans often correspond with urban exploitation in mammal species, but these relationships differ by taxa and trophic guild. Variation among or within traits may be a yet untested explanation for the non-generality of species-trait relationships in cities. Using camera trap data from 1492 sites throughout the contiguous USA in 2019, we investigated if mammal species with greater intraspecific trait variation have higher degrees of urban occupancy. We hypothesized that intraspecific trait variation would correspond with urban occupancy, but that the strength of these relationships would vary by taxonomic order due to expected phylogenetic constraints. Mean trait values (average home range size, body mass, group size, weaning age, litter size, and diet composition) varied widely across orders. The only traits that affected urban association across all species corresponded with demography (litter size), while responses across orders were more variable and informative. Mean trait values associated with home range and body size had informative relationships with urbanization for Cetartiodactyla, Rodentia, and Carnivora, while intraspecific variation in traits corresponding with diet (Carnivora), demography (Cetartiodactyla, Carnivora, Rodentia), and temporal responses to humans (Carnivora) had informative relationships to urbanization. This is the first study investigating mammalian species-level trait variation and its relationship to urban exploitation across many traits and taxa. Since natural selection requires trait variation, the variation of demographic traits, like litter size, can have significant implications for wildlife management and conservation. Our results also provide further evidence for omnivory as a form of dietary plasticity supporting urban accessibility in higher trophic guilds (e.g., Carnivora). Using this information, we can better manage and understand which species occupy and adapt to cities, thereby promoting human-wildlife coexistence.


Assuntos
Carnívoros , Ecossistema , Animais , Humanos , Filogenia , Mamíferos , Roedores , Urbanização
8.
J Cutan Pathol ; 50(6): 530-535, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36239041

RESUMO

BACKGROUND: Ongoing controversy exists regarding terminology used to describe atypical melanocytic nevi. Efforts to standardize nomenclature, including the 1992 NIH consensus conference, have been largely unsuccessful. Significant advances have revealed an increasingly detailed genetic picture of melanocytic neoplasms, including strong evidence for the existence of those with "intermediate" behavior. METHODS: We sent an electronic survey to dermatopathologists (n = 846) to assess trends in nomenclature usage and attitudes toward developing new consensus nomenclature for atypical melanocytic nevi. RESULTS: There were 229 complete responses (27.1% response rate). The most used/preferred nomenclature was "dysplastic nevus" (43%/39%, respectively), followed by the NIH-recommended terminology (28%/26%). Three-tier grading systems were most heavily used/preferred (79%/63%). Dermatopathologists based in New England were most likely to use the NIH terminology; on the other hand, "dysplastic nevus" or "other" were most used elsewhere (p = 0.029). Most (76%) expressed at least "moderate" enthusiasm for developing consensus nomenclature, with 47% "very" or "extremely" enthusiastic. CONCLUSION: Little has changed with the wide variation in terminology for atypical melanocytic nevi. There continues to be no one dominant terminology in use. However, there is enthusiasm for standardization. A new attempt at updated consensus nomenclature may be fruitful.


Assuntos
Síndrome do Nevo Displásico , Nevo Pigmentado , Neoplasias Cutâneas , Humanos , Inquéritos e Questionários , Padrões de Referência
9.
J Immunother Cancer ; 10(10)2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36307152

RESUMO

Talimogene laherparepvec (T-VEC) has become an increasingly popular treatment option for surgically non-resectable, recurrent melanoma, usually of cutaneous metastases. The complete response (CR) rate has been reported to be ~20% with a median of ~9 months to achieve it. In real-world practice, decrease of tumor size often occurs rapidly within the first 2-3 months, while improvement of the pigmentation takes several more months. Such clinical observation of lasting pigmentation could be explained by tumorous melanosis-a histopathological term referring to the presence of a melanophage-rich inflammatory infiltrate without remaining viable tumor cells. Herein, we report six patients with metastatic cutaneous melanoma who were treated with T-VEC. Biopsies were performed after observing clinical responses in the injected tumors. Pathological evaluation demonstrated non-viable or absent tumor tissue with tumorous melanosis in all cases. To accurately assess response to therapy and potentially decrease unnecessary additional T-VEC treatments, serial biopsy of 'stable' lesions should be considered to assess the presence or absence of viable tumor.


Assuntos
Melanoma , Melanose , Terapia Viral Oncolítica , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/tratamento farmacológico , Recidiva Local de Neoplasia/terapia , Melanose/diagnóstico , Melanose/terapia , Progressão da Doença , Melanoma Maligno Cutâneo
10.
J Air Waste Manag Assoc ; 72(11): 1219-1230, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35759771

RESUMO

Many low-cost particle sensors are available for routine air quality monitoring of PM2.5, but there are concerns about the accuracy and precision of the reported data, particularly in humid conditions. The objectives of this study are to evaluate the Sensirion SPS30 particulate matter (PM) sensor against regulatory methods for measurement of real-time particulate matter concentrations and to evaluate the effectiveness of the Intelligent AirTM sensor pack for remote deployment and monitoring. To achieve this, we co-located the Intelligent AirTM sensor pack, developed at Clemson University and built around the Sensirion SPS30, to collect data from July 29, 2019, to December 12, 2019, at a regulatory site in Columbia, South Carolina. When compared to the Federal Equivalent Methods, the SPS30 showed an average bias adjusted R2 = 0.75, mean bias error of -1.59, and a root mean square error of 2.10 for 24-hour average trimmed measurements over 93 days, and R2 = 0.57, mean bias error of -1.61, and a root mean square error of 3.029, for 1-hr average trimmed measurements over 2300 hours when the central 99% of data was retained with a data completeness of 75% or greater. The Intelligent AirTM sensor pack is designed to promote long-term deployment and includes a solar panel and battery backup, protection from the elements, and the ability to upload data via a cellular network. Overall, we conclude that the SPS30 PM sensor and the Intelligent AirTM sensor pack have the potential for greatly increasing the spatial density of particulate matter measurements, but more work is needed to understand and calibrate sensor measurements.Implications: This work adds to the growing body of research that indicates that low-cost sensors of particulate matter (PM) for air quality monitoring has a promising future, and yet much work is left to be done. This work shows that the level of data processing and filtering effects how the low-cost sensors compare to existing federal reference and equivalence methods: more data filtering at low PM levels worsens the data comparison, while longer time averaging improves the measurement comparisons. Improvements must be made to how we handle, calibrate, and correct PM data from low-cost sensors before the data can be reliably used for air quality monitoring and attainment.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Humanos , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Poluição do Ar/análise , Material Particulado/análise , Internet
11.
Glob Chang Biol ; 27(21): 5446-5459, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34405496

RESUMO

Urban biodiversity provides critical ecosystem services and is a key component to environmentally and socially sustainable cities. However, biodiversity varies greatly within and among cities, leading to human communities with changing and unequal experiences with nature. The "luxury effect," a hypothesis that predicts a positive correlation between wealth, typically measured by per capita income, and species richness may be one indication of these inequities. While the luxury effect is well studied for some taxa, it has rarely been investigated for mammals, which provide unique ecosystem services (e.g., biological pest control) and exhibit significant potential for negative human-wildlife interactions (e.g., nuisances or conflicts). We analyzed a large dataset of mammal detections across 20 North American cities to test whether the luxury effect is consistent for medium- to large-sized terrestrial mammals across diverse urban contexts. Overall, support for the luxury effect, as indicated by per capita income, was inconsistent; we found evidence of a luxury effect in approximately half of our study cities. Species richness was, however, highly and negatively correlated with urban intensity in most cities. We thus suggest that economic factors play an important role in shaping urban mammal communities for some cities and species, but that the strongest driver of urban mammal diversity is urban intensity. To better understand the complexity of urban ecosystems, ecologists and social scientists must consider the social and political factors that drive inequitable human experiences with nature in cities.


Assuntos
Ecossistema , Urbanização , Animais , Biodiversidade , Cidades , Humanos , Mamíferos
12.
Materials (Basel) ; 14(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209884

RESUMO

Improving the longevity of composite restorations has proven to be difficult when they are bonded to dentin. Dentin demineralization leaves collagen fibrils susceptible to enzymatic digestion, which causes breakdown of the resin-dentin interface. Therefore, measures for counteracting the enzymatic environment by enhancing dentin collagen's resistance to degradation have the potential to improve the durability of dental composite restorations. This study aimed to evaluate the effects of polyphenol-rich extracts and a chemical cross-linker on the cross-linking interaction, resistance to digestion, and endogenous matrix metalloproteinase (MMP) activities of dentin collagen under clinically relevant conditions. Ten-µm-thick films were cut from dentin slabs of non-carious extracted human third molars. Following demineralization, polyphenol-rich extracts-including grape seed (GSE), green tea (GTE), and cranberry juice (CJE)-or chemical cross-linker carbodiimide with n-hydroxysuccinimide (EDC/NHS) were applied to the demineralized dentin surfaces for 30 s. The collagen cross-linking, bio-stabilization, and gelatinolytic activities of MMPs 2 and 9 were studied by using Fourier-transform infrared spectroscopy, weight loss, hydroxyproline release, scanning/transmission electron microscopy, and in situ zymography. All treatments significantly increased resistance to collagenase degradation and reduced the gelatinolytic MMP activity of dentin collagen compared to the untreated control. The CJE- and GSE-treated groups were more resistant to digestion than the GTE- or EDC/NHS-treated ones (p < 0.05), which was consistent with the cross-linking interaction found with FTIR and the in situ performance on the acid-etched dentin surface found with SEM/TEM. The collagen films treated with CJE showed the lowest MMP activity, followed by GSE, GTE, and, finally, EDC/NHS. The CJE-treated dentin collagen rapidly increased its resistance to digestion and MMP inhibition. An application of CJE as short as 30 s may be a clinically feasible approach to improving the longevity of dentin bonding in composite restorations.

13.
Glob Chang Biol ; 27(16): 3718-3731, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33887083

RESUMO

Human activity and land use change impact every landscape on Earth, driving declines in many animal species while benefiting others. Species ecological and life history traits may predict success in human-dominated landscapes such that only species with "winning" combinations of traits will persist in disturbed environments. However, this link between species traits and successful coexistence with humans remains obscured by the complexity of anthropogenic disturbances and variability among study systems. We compiled detection data for 24 mammal species from 61 populations across North America to quantify the effects of (1) the direct presence of people and (2) the human footprint (landscape modification) on mammal occurrence and activity levels. Thirty-three percent of mammal species exhibited a net negative response (i.e., reduced occurrence or activity) to increasing human presence and/or footprint across populations, whereas 58% of species were positively associated with increasing disturbance. However, apparent benefits of human presence and footprint tended to decrease or disappear at higher disturbance levels, indicative of thresholds in mammal species' capacity to tolerate disturbance or exploit human-dominated landscapes. Species ecological and life history traits were strong predictors of their responses to human footprint, with increasing footprint favoring smaller, less carnivorous, faster-reproducing species. The positive and negative effects of human presence were distributed more randomly with respect to species trait values, with apparent winners and losers across a range of body sizes and dietary guilds. Differential responses by some species to human presence and human footprint highlight the importance of considering these two forms of human disturbance separately when estimating anthropogenic impacts on wildlife. Our approach provides insights into the complex mechanisms through which human activities shape mammal communities globally, revealing the drivers of the loss of larger predators in human-modified landscapes.


Assuntos
Animais Selvagens , Características de História de Vida , Animais , Ecossistema , Atividades Humanas , Humanos , Mamíferos , América do Norte
14.
Dermatol Online J ; 27(12)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35499433

RESUMO

Cutaneous dystrophic calcification as a late change of radiation therapy is a rarely reported finding. Initially, it was almost exclusively described as occurring on the chest wall in breast cancer patients but has since been described in several other malignancies. We describe the first reported case of radiotherapy-induced calcinosis cutis occurring at the site of a previous liposarcoma. Review of the literature including risk factors, similar cases, pathophysiology, and management is also explored.


Assuntos
Calcinose , Lipossarcoma , Dermatopatias , Calcinose/etiologia , Calcinose/patologia , Humanos , Lipossarcoma/radioterapia , Pele/patologia , Dermatopatias/patologia
15.
Biol Conserv ; 256: 108984, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36531528

RESUMO

COVID-19 has altered many aspects of everyday life. For the scientific community, the pandemic has called upon investigators to continue work in novel ways, curtailing field and lab research. However, this unprecedented situation also offers an opportunity for researchers to optimize and further develop available field methods. Camera traps are one example of a tool used in science to answer questions about wildlife ecology, conservation, and management. Camera traps have long battery lives, lasting more than a year in certain cases, and photo storage capacity, with some models capable of wirelessly transmitting images from the field. This allows researchers to deploy cameras without having to check them for up to a year or more, making them an ideal field research tool during restrictions on in-person research activities such as COVID-19 lockdowns. As technological advances allow cameras to collect increasingly greater numbers of photos and videos, the analysis techniques for large amounts of data are evolving. Here, we describe the most common research questions suitable for camera trap studies and their importance for biodiversity conservation. As COVID-19 continues to affect how people interact with the natural environment, we discuss novel questions for which camera traps can provide insights on. We conclude by summarizing the results of a systematic review of camera trap studies, providing data on target taxa, geographic distribution, publication rate, and publication venues to help researchers planning to use camera traps in response to the current changes in human activity.

16.
Ann N Y Acad Sci ; 1469(1): 52-64, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32216157

RESUMO

By involving the public, citizen science runs against the grain of an idealized science that leaves out the human element, and thus provides new opportunities for ecological research and society. We classify the goals of citizen science in ecology and environment into four broad categories: (1) scientific, (2) participant benefits, (3) community, and (4) policy. Although none of these goals have been well studied, we review the literature showing that these projects are most effective in tracking ecological trends over large swaths of space and time, and discuss the challenges of recruiting, training, retaining, and educating participants, maintaining and disseminating high-quality data, and connecting with the larger community and policy. Biomedical studies, where patients participate in their own treatment in randomized trials, provide an interesting comparison with citizen science in ecology, sharing challenges in recruitment and involvement of nonscientists and ethical conduct of research. Future study will help address the ethical difficulties and enhance ways for citizen science in ecology and the environment to complement scientific discovery, involve and educate the public, and guide policy founded in science and the local community.


Assuntos
Ciência do Cidadão , Ecologia , Humanos
17.
J Community Psychol ; 46(5): 567-574, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30104802

RESUMO

This study examined the role of hope and community in achieving and/or maintaining a successful recovery, and their relationships to quality of life for individuals in recovery. The sample included 229 participants in 42 Oxford House sober living homes in 3 locations in the United States. In this cross-sectional investigation, we assessed whether hope and sense of community were predictors of quality of life for individuals living in recovery homes. Findings indicated that both hope and sense of community were predictors supporting contextual as well as individual characteristics as possible influences on recovery trajectories. These findings have implications for both individual and systems-level resource or competency-based interventions, and they suggest one of the important functions of a recovery residence is in the creation of a sense of community.


Assuntos
Lares para Grupos , Esperança , Qualidade de Vida/psicologia , Apoio Social , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Substâncias/psicologia , Estados Unidos
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