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1.
Am Nat ; 203(1): 124-138, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38207136

RESUMO

AbstractSpecies' distributions can take many different forms. For example, fat-tailed or skewed distributions are very common in nature, as these can naturally emerge as a result of individual variability and asymmetric environmental tolerances, respectively. Studying the basic shape of distributions can teach us a lot about the ways climatic processes and historical contingencies shape ecological communities. Yet we still lack a general understanding of how their shapes and properties compare to each other along gradients. Here, we use Bayesian nonlinear models to quantify range shape properties in empirical plant distributions. With this approach, we are able to distil the shape of plant distributions and compare them along gradients and across species. Studying the relationship between distribution properties, we revealed the existence of broad macroecological patterns along environmental gradients-such as those expected from Rapoport's rule and the abiotic stress limitation hypothesis. We also find that some aspects of the shape of observed ranges-such as kurtosis and skewness of the distributions-could be intrinsic properties of species or the result of their historical contexts. Overall, our modeling approach and results untangle the general shape of plant distributions and provide a mapping of how this changes along environmental gradients.


Assuntos
Teorema de Bayes , Dispersão Vegetal , Ecologia
2.
J Gambl Stud ; 37(2): 483-495, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32436155

RESUMO

People with gambling disorder (GD) exhibit distorted cognitions and superstitious beliefs more often than the general population. Similarly, difficulties in coping and emotion dysregulation are more prevalent among those with GD, and could determine the onset of GD in particularly vulnerable groups such as adolescents. This study examines the relationship between gambling severity and gambling-related cognitions with coping strategies and emotion regulation. Also, it explores how accurately gambling severity and gambling-related cognitions were able to predict emotion regulation and coping strategies. Two groups were recruited and analyzed: a community sample comprising 250 adolescents and young adults from secondary education schools, and a clinical sample of 31 patients with similar age characteristics seeking treatment for GD. The participants from the clinical sample scored higher on gambling severity, emotion dysregulation, cognitive biases, and maladaptive coping strategies. In the community sample, cognitive biases mediated the relationship between sex and emotion dysregulation and disengagement. People with GD use more often than controls maladaptive emotion regulation strategies to manage negative emotional states. This perspective emphasizes the need to focus on coping with emotions, as opposed to coping with problems, as the best approach to tackle gambling problems.


Assuntos
Comportamento Aditivo/psicologia , Cognição/fisiologia , Regulação Emocional , Jogo de Azar/psicologia , Adaptação Psicológica , Adolescente , Emoções , Humanos , Masculino , Autocontrole/psicologia , Inquéritos e Questionários
3.
J Gambl Stud ; 36(3): 809-828, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31828697

RESUMO

Participation in gambling is rising in older adults. Indeed, in the coming years, engagement in gambling as a social activity is expected to increase more sharply in the elderly than in any other age group. Due to their exposure to powerful age-specific risk factors such as isolation, inactivity and failing health, older people are highly vulnerable to gambling-related problems. This study aimed to explore the existence of empirical clusters related to gambling habits in a sample of elderly participants from the general population. The sample included n = 361 participants, age range 50-90 years (mean 73.8, SD 8.4). Empirical clusters were identified through a two-step clustering analysis based on a broad set of indicators, including sociodemographic features, psychopathological state, substance use, life events, gambling preferences and scores on screening measures of gambling severity. The prevalence of GD in the study was 1.4%. Two clusters were identified: (a) cluster 1 (labeled as "low risk of gambling problems", n = 265, 73.4%), which included the higher proportion of non-gamblers or individuals who engage only in non-strategic gambling, women, widowed, and lower levels of education (no individual into this group met criteria for GD); and (b) cluster 2 (labeled as "higher risk of gambling problems", n = 96, 26.6%), which included the higher proportion of men, who reported both non-strategic and strategic gambling preferences (all participants diagnosed of GD were grouped into this cluster), older age, longer history of gambling, higher gambling severity, higher use of substances and worse psychopathological state. The elderly constitute a heterogeneous group with regard to gambling phenotypes. The results of this study may prove particularly useful for developing reliable screening tools able to identify older patients at a high risk of gambling problems, and for designing effective prevention and intervention programs.


Assuntos
Comportamento Aditivo/psicologia , Jogo de Azar/psicologia , Solidão/psicologia , Isolamento Social/psicologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Apoio Social , Fatores Socioeconômicos , Transtornos Relacionados ao Uso de Substâncias/psicologia
4.
Environ Res ; 174: 125-134, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31071493

RESUMO

BACKGROUND: Electronic cigarettes (E-cigarettes) generate aerosol containing metal contaminants. Our goals were to quantify aerosol metal concentrations and to compare the effects of power setting and device type (closed-system vs. open-system) on metal release. METHODS: Aerosol samples were collected from two closed-system devices (a cigalike and pod) and two open-system devices (mods). Each open-system device was operated at three different power settings to examine the effect of device power on metal release. Concentrations of 14 metals in e-cigarette aerosol collected via droplet deposition were measured using inductively coupled plasma mass spectroscopy. Aerosol metal concentrations were reported as mass fractions (µg/kg) in the e-liquid. RESULTS: For open-system device 1 (OD1), median arsenic (As), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), antimony (Sb), tin (Sn), and zinc (Zn) concentrations increased 14, 54, 17, 30, 41, 96, 14, 81, 631, and 7-fold when the device power was increased from low (20 W) to intermediate (40 W) setting. When the power was further increased from intermediate (40 W) to high (80 W) setting, concentrations of As, Cr, Cu, Mn, Ni, and Sb did not change significantly. For open-system device 2 (OD2), Cr and Mn concentrations increased significantly when device power was increased from low (40 W) to intermediate (120 W) setting, and then decreased significantly when power was further increased from intermediate (120 W) to high (200 W) setting. Among the four devices, aerosol metal concentrations were higher for the open-system than the closed-system devices, except for aluminum (Al) and uranium (U). For Cr, median (interquartile range) concentrations (µg/kg) from the open-system devices were 2.51 (1.55, 4.23) and 15.6 (7.88, 54.5) vs. 0.39 (0.05, 0.72) and 0.41 (0.34, 0.57) for the closed-system devices. For Ni, concentrations (µg/kg) from the open-system devices were 793 (508, 1169) and 2148 (851, 3397) vs. 1.32 (0.39, 3.35) and 11.9 (10.7, 22.7) from the closed-system devices. Inhalation of 0% and 100% of samples from OD1, 7.4% and 88.9% from OD2 by typical e-cigarette users would exceed chronic minimum risk levels (MRL) of Mn and Ni, respectively. No MRL exceedance was predicted for the closed-system devices. A large fraction of users of OD1 (100%) and OD2 (77.8%) would be exposed to Ni levels higher than those from reference tobacco cigarette 3R4F. CONCLUSIONS: Our findings suggest that power setting and device type affect metal release from devices to aerosol which would subsequently be inhaled by users. Metal concentrations from open-system devices first increased with device power, and then leveled off for most metals. Open-system devices generate aerosol with higher metal concentrations than closed-system devices. These findings inform tobacco regulatory science, policy makers and health professionals on potential metal health risks associated with e-cigarette use, design and manufacturing.


Assuntos
Aerossóis/análise , Sistemas Eletrônicos de Liberação de Nicotina , Monitoramento Ambiental , Metais/análise , Cromo , Metais Pesados , Níquel
5.
Nat Commun ; 11(1): 4086, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796828

RESUMO

Ecological communities often show changes in populations and their interactions over time. To date, however, it has been challenging to effectively untangle the mechanisms shaping such dynamics. One approach that has yet to be fully explored is to treat the varying structure of empirical communities-i.e. their network of interactions-as time series. Here, we follow this approach by applying a network-comparison technique to study the seasonal dynamics of plant-pollinator networks. We find that the structure of these networks is extremely variable, where species constantly change how they interact with each other within seasons. Most importantly, we find the holistic dynamic of plants and pollinators to be remarkably coherent across years, allowing us to reveal general rules by which species first enter, then change their roles, and finally leave the networks. Overall, our results disentangle key aspects of species' interaction turnover, phenology, and seasonal assembly/disassembly processes in empirical plant-pollinator communities.


Assuntos
Polinização/fisiologia , Animais , Biodiversidade , Biota , Insetos/fisiologia , Estações do Ano
6.
Front Psychiatry ; 11: 482, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547432

RESUMO

BACKGROUND AND OBJECTIVES: The Internet provides easy access to multiple types of gambling and has led to changes in betting habits. A severe rise in problematic gambling has been predicted among all sectors of the population, and studies are required to assess the emerging phenotypes related to the new structures of gambling activities. This study aimed to explore the existence of latent classes associated with gambling habits among treatment-seeking gamblers due to Online Sports Betting (OSB). METHOD: Initial sample included n = 4,516 patients consecutively admitted for treatment in a hospital unit specialized in behavioral addictions. Two-step clustering analysis was used within the subsample of n = 323 patients who reported problems related with OSB, within a set of indicators including sociodemographics, psychopathological distress, personality, and severity of the gambling activity. RESULTS: The prevalence of OSB as a main type of gambling problem in the study was 7.2% (95% confidence interval: 6.4 to 7.9%). Two latent clusters were identified, with differences in sociodemographics and clinical status. Cluster 1 (n = 247, 76.5%) grouped patients that were more affected due to the OSB behaviors, and it was characterized by non-married patients, lower socioeconomic position index, higher comorbidity with other substance related addictions, younger age, and early onset of the gambling activity, as well as higher debts due to the OSB, higher psychopathological distress, and a more dysfunctional personality profile. Cluster 2 (n = 76, 23.5%) grouped patients that were less affected by OSB, mostly married (or living with a stable partner), with higher social position levels, older age and older onset of the gambling activity, as well as a more functional psychopathological and personality profile. CONCLUSION: The increasing understanding of latent classes underlying OSB phenotypes is essential in guiding the development of reliable screening tools to identify individuals highly vulnerable to addictive behaviors among Internet gamblers, as well as in planning prevention and treatment initiatives focused on the precise profiles of these patients.

7.
PLoS One ; 15(5): e0233222, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428026

RESUMO

The use of instruments originally developed for measuring gambling activity in younger populations may not be appropriate in older age individuals. The aim of this study was to examine the presence of problematic and disordered gambling in seniors aged 50 or over, and study the reliability and validity properties of the SOGS (a screening measure to identify gambling related problems). Two independent samples were recruited: a clinical group of n = 47 patients seeking treatment at a Pathological Gambling Outpatient Unit, and a population-based group of n = 361 participants recruited from the same geographical area. Confirmatory factor analysis verified the bifactor structure for the SOGS with two correlated underlying dimensions [measuring the impact of gambling on the self primarily (Cronbach's alpha α = 0.87) or on both the self and others also (α = 0.82)], and a global dimension of gambling severity (also with excellent internal consistency, α = 0.90). The SOG obtained excellent accuracy/validity for identifying gambling severity based on the DSM-5 criteria (area under the ROC curve AUC = 0.97 for discriminating disordered gambling and AUC = 0.91 for discriminating problem gambling), and good convergent validity with external measures of gambling (Pearson's correlation R = 0.91 with the total number of DSM-5 criteria for gambling disorder, and R = 0.55 with the debts accumulated due to gambling) and psychopathology (R = 0.50, 0.43 and 0.44 with the SCL-90R depression, anxiety and GSI scales). The optimal cutoff point for identifying gambling disorder was 4 (sensitivity Se = 92.3% and specificity Sp = 98.6%) and 2 for identifying problem gambling (Se = 78.8% and Sp = 96.7%). This study provides empirical support for the reliability and validity of the SOGS for assessing problem gambling in elders, and identifies two specific factors that could help both research and clinical decision-making, based on the severity and consequences of the gambling activity.


Assuntos
Comportamento Aditivo/diagnóstico , Jogo de Azar/psicologia , Psicometria/métodos , Fatores Etários , Idoso , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Inquéritos e Questionários
8.
J R Soc Interface ; 16(151): 20180747, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30958192

RESUMO

Null models have become a crucial tool for understanding structure within incidence matrices across multiple biological contexts. For example, they have been widely used for the study of ecological and biogeographic questions, testing hypotheses regarding patterns of community assembly, species co-occurrence and biodiversity. However, to our knowledge we remain without a general and flexible approach to study the mechanisms explaining such structures. Here, we provide a method for generating 'correlation-informed' null models, which combine the classic concept of null models and tools from community ecology, like joint statistical modelling. Generally, this model allows us to assess whether the information encoded within any given correlation matrix is predictive for explaining structural patterns observed within an incidence matrix. To demonstrate its utility, we apply our approach to two different case studies that represent examples of common scenarios encountered in community ecology. First, we use a phylogenetically informed null model to detect a strong evolutionary fingerprint within empirically observed food webs, reflecting key differences in the impact of shared evolutionary history when shaping the interactions of predators or prey. Second, we use multiple informed null models to identify which factors determine structural patterns of species assemblages, focusing in on the study of nestedness and the influence of site size, isolation, species range and species richness. In addition to offering a versatile way to study the mechanisms shaping the structure of any incidence matrix, including those describing ecological communities, our approach can also be adapted further to test even more sophisticated hypotheses.


Assuntos
Biodiversidade , Evolução Biológica , Cadeia Alimentar , Modelos Biológicos , Animais , Ecologia
9.
Sci Total Environ ; 650(Pt 2): 2239-2250, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30292117

RESUMO

At gas stations, fuel vapors are released into the atmosphere from storage tanks through vent pipes. Little is known about when releases occur, their magnitude, and their potential health consequences. Our goals were to quantify vent pipe releases and examine exceedance of short-term exposure limits to benzene around gas stations. At two US gas stations, we measured volumetric vent pipe flow rates and pressure in the storage tank headspace at high temporal resolution for approximately three weeks. Based on the measured vent emission and meteorological data, we performed air dispersion modeling to obtain hourly atmospheric benzene levels. For the two gas stations, average vent emission factors were 0.17 and 0.21 kg of gasoline per 1000 L dispensed. Modeling suggests that at one gas station, a 1-hour Reference Exposure Level (REL) for benzene for the general population (8 ppb) was exceeded only closer than 50 m from the station's center. At the other gas station, the REL was exceeded on two different days and up to 160 m from the center, likely due to non-compliant bulk fuel deliveries. A minimum risk level for intermediate duration (>14-364 days) benzene exposure (6 ppb) was exceeded at the elevation of the vent pipe opening up to 7 and 8 m from the two gas stations. Recorded vent emission factors were >10 times higher than estimates used to derive setback distances for gas stations. Setback distances should be revisited to address temporal variability and pollution controls in vent emissions.

10.
Environ Int ; 127: 142-159, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30913459

RESUMO

BACKGROUND: Crowd-sourced traffic data potentially allow prediction of traffic-related air pollution at high temporal and spatial resolution. OBJECTIVES: To examine associations (1) of radar-based traffic measurements with congestion colors displayed on crowd-sourced traffic data maps and (2) of black carbon (BC) levels with radar and crowd-sourced traffic data. METHODS: At an off-ramp of an interstate and a small one-way street in a mixed-use area in New York City, we used radar devices to obtain vehicle speeds and flows (hourly counts) for cars and trucks. At these radar sites and at an additional non-radar equipped site at a 2-way street, we monitored BC levels using aethalometers in the summer and early fall of 2017. At all three sites, free-flow traffic conditions typically did not occur due to the nearby presence of traffic lights and forced turns. We also downloaded real-time traffic maps from a crowd-sourced traffic data provider and assigned an ordinal integer congestion color code CCC to the congestion colors, ranging from 1 (dark red) to 5 (gray). RESULTS: CCC increased with vehicle speed. Traffic flow was highest for intermediate speeds and intermediate CCC. Regression analyses showed that BC levels increased with either segregated or total vehicle flows. At the off-ramp, time-dependent BC levels can be inferred from time-dependent CCC and radar-derived mean vehicle flow data. A unit decrease in CCC for a mean traffic flow of 100 vehicles/h was associated with a mean (95% CI) increase in BC levels of 0.023 (0.028, 0.018) µg/m3. At the small 1-way and the 2-way street, BC levels were also negatively associated with CCC, though at a >0.05 significance level. CONCLUSIONS: Use of inexpensive crowd-sourced traffic data holds great promise in air pollution modeling and health studies. Time-dependent traffic-related primary air pollution levels may be inferred from radar-calibrated crowd-sourced traffic data, in our case radar-derived mean traffic flow and widely available CCC data. However, at some locations mean traffic flow data may already be available.


Assuntos
Poluição Relacionada com o Tráfego , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Calibragem , Crowdsourcing , Cidade de Nova Iorque , Radar , Fuligem/análise , Emissões de Veículos/análise
11.
Nat Commun ; 9(1): 2603, 2018 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973596

RESUMO

Although the structure of empirical food webs can differ between ecosystems, there is growing evidence of multiple ways in which they also exhibit common topological properties. To reconcile these contrasting observations, we postulate the existence of a backbone of interactions underlying all ecological networks-a common substructure within every network comprised of species playing similar ecological roles-and a periphery of species whose idiosyncrasies help explain the differences between networks. To test this conjecture, we introduce a new approach to investigate the structural similarity of 411 food webs from multiple environments and biomes. We first find significant differences in the way species in different ecosystems interact with each other. Despite these differences, we then show that there is compelling evidence of a common backbone of interactions underpinning all food webs. We expect that identifying a backbone of interactions will shed light on the rules driving assembly of different ecological communities.


Assuntos
Comportamento Competitivo/fisiologia , Cadeia Alimentar , Modelos Estatísticos , Comportamento Predatório/fisiologia , Animais , Conjuntos de Dados como Assunto , Ecossistema , Análise de Componente Principal
12.
Curr Environ Health Rep ; 2(4): 412-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26435043

RESUMO

At gas stations, fuel is stored and transferred between tanker trucks, storage tanks, and vehicle tanks. During both storage and transfer, a small fraction of unburned fuel is typically released to the environment unless pollution prevention technology is used. While the fraction may be small, the cumulative release can be substantial because of the large quantities of fuel sold. The cumulative release of unburned fuel is a public health concern because gas stations are widely distributed in residential areas and because fuel contains toxic and carcinogenic chemicals. We review the pathways through which gasoline is chronically released to atmospheric, aqueous, and subsurface environments, and how these releases may adversely affect human health. Adoption of suitable pollution prevention technology should not only be based on equipment and maintenance cost but also on energy- and health care-saving benefits.


Assuntos
Poluentes Atmosféricos/análise , Exposição Ambiental/análise , Gasolina/análise , Exposição Ambiental/prevenção & controle , Monitoramento Ambiental/métodos , Gasolina/efeitos adversos , Humanos , Veículos Automotores
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