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1.
Subst Use Misuse ; 56(2): 192-204, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33412950

RESUMO

Background: Substances that can be vaped include nicotine, marijuana, cocaine, heroin, and a range of synthetic drugs called new psychoactive substances (NPS). Due to the rising popularity of vaping among adolescents, it is crucial to understand the relationships between vaping and illicit drug use. Objectives: This paper examined the prevalence and trends of using vaping devices, marijuana vaping, marijuana products, synthetic cannabinoids and mist contents among youth. Methods: The study utilized 5 sets of public cross-sectional national data from the "Monitoring the Future" surveys during 2014-2018. It employed logistic regression to analyze the data. Results: There was an increase from 10.5% in 2017 to 20.8% in 2018 for the past 30-day use of vaping devices among 12th graders. Furthermore, there was an increase from 21.6% in 2017 to 34.5% in 2018 for the past 12-month use of marijuana via vaping device among 12th-grade marijuana users. Additionally, there were significant associations between vaping device use and marijuana vaping, between vaping device use and marijuana use, between vaping device use and synthetic cannabinoids use, and between marijuana use and synthetic cannabinoids use from 2016 to 2018. Conclusions: Vaping emerged as another major route of marijuana administration among youth. Adolescent marijuana users had higher odds of using synthetic cannabinoids. This finding highlighted the importance of understanding what adolescent substance consumption pattern would be where marijuana was legalized. It also supported the hypothesis that vaping devices use correlates with, or is associated with, marijuana and synthetic cannabinoids use.


Assuntos
Canabinoides/administração & dosagem , Fumar Maconha/epidemiologia , Uso da Maconha/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Vaping/epidemiologia , Administração por Inalação , Adolescente , Cannabis , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Inquéritos e Questionários , Estados Unidos/epidemiologia
2.
J Environ Manage ; 249: 109083, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518865

RESUMO

Mixed sand and gravel beaches pose special management issues as they are morphologically distinct from either pure sand or shingle beaches. On the mixed sand and gravel beaches of the Canterbury Bight, New Zealand, displacement of sediments operates within a two-part sediment transport system. The large sediments are retained in the beaches, while the fine sand, silt, and mud are transported offshore to the continental shelf. While the susceptibility of sediments to size-reduction is dependent on the textural mixture of sediments, the actual size-reduction takes place during sediment transport, or displacement, in the active surf zone of the beach. The authors outline a method that incorporates the sediment reduction susceptibility of beach sediments from the textural mixture, twenty years of wave-hindcast data, and sediment tracer experiments to model sediment displacement in mixed sand and gravel beach environments of the Canterbury Bight. Results show that the textural mix of the sediments influences not only the rate of loss to size-reduction but also the time taken for sediment to be transported along a beach continuum within the surf zone. The authors modelled time-frames to achieve three target percentages of sediment displacement: (1) ten percent, (2) fifty percent, and (3) a range of zero to one hundred percent. Ten percent displacement of sediments was predicted to take between four and eighty-eight weeks, fifty percent displacement between one and sixteen years, and a hundred percent displacement up to two-hundred and thirty years, depending on the textural composition of sediments along the coast based on the actual wave action occurring along this coastline.


Assuntos
Sistemas de Informação Geográfica , Sedimentos Geológicos , Praias , Nova Zelândia , Dióxido de Silício
3.
Health Serv J ; 126(6488): 30-1, 2016 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-30084612

RESUMO

The realization that some incidents involving fire and mental health service users could have been avoided led to holistic safety assessments, say David Marsden and Paula Breeze.


Assuntos
Incêndios , Pessoas Mentalmente Doentes , Gestão da Segurança , Medicina Estatal
4.
Curr Biol ; 17(24): 2150-6, 2007 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-18083515

RESUMO

Human menopause is remarkable in that reproductive senescence is markedly accelerated relative to somatic aging, leaving an extended postreproductive period for a large proportion of women. Functional explanations for this are debated, in part because comparative data from closely related species are inadequate. Existing studies of chimpanzees are based on very small samples and have not provided clear conclusions about the reproductive function of aging females. These studies have not examined whether reproductive senescence in chimpanzees exceeds the pace of general aging, as in humans, or occurs in parallel with declines in overall health, as in many other animals. In order to remedy these problems, we examined fertility and mortality patterns in six free-living chimpanzee populations. Chimpanzee and human birth rates show similar patterns of decline beginning in the fourth decade, suggesting that the physiology of reproductive senescence was relatively conserved in human evolution. However, in contrast to humans, chimpanzee fertility declines are consistent with declines in survivorship, and healthy females maintain high birth rates late into life. Thus, in contrast to recent claims, we find no evidence that menopause is a typical characteristic of chimpanzee life histories.


Assuntos
Envelhecimento/fisiologia , Evolução Biológica , Fertilidade/fisiologia , Menopausa , Pan troglodytes/fisiologia , Animais , Animais Selvagens , Coeficiente de Natalidade , Feminino , Humanos
5.
Org Biomol Chem ; 8(23): 5313-23, 2010 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-20886127

RESUMO

The screening of large arrays of drug-like small-molecules was traditionally a time consuming and resource intensive task. New methodology developed within our laboratories provides an attractive low cost, 3D microarray-assisted screening platform that could be used to rapidly assay thousands of compounds. As a proof-of-principle the platform was exploited to screen a number of quorum sensing analogs. Quorum sensing is used by bacterium to initiate and spread infection; in this context its modulation may have significant clinical value. 3D microarray slides were probed with fluorescently labeled ligand-binding domains of the LuxR homolog CarR from Erwinia carotovora subsp. carotovora. The 3D microarray platform was used to discover the biologically active chloro-pyridine pharmacophore, which was validated using a fluorometric ligand binding assay and ITC. Analogs containing the chloro-pyridine pharmacophore were found to be potent inhibitors of N-acyl-homoserine-lactone (AHL) mediated quorum sensing phenotypes in Serratia (IC(50) = ∼5 µM) and Pseudomonas aeruginosa (IC(50) = 10-20 µM).


Assuntos
Percepção de Quorum , Bibliotecas de Moléculas Pequenas/química , Estrutura Molecular , Pectobacterium carotovorum/química
6.
J Appl Clin Med Phys ; 11(4): 3301, 2010 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-21081891

RESUMO

The objective of this study has been to compare treatment plans for patients treated with electronic brachytherapy (eBx) using the Axxent System as adjuvant therapy for early stage breast cancer with treatment plans prepared from the same CT image sets using an Ir-192 source. Patients were implanted with an appropriately sized Axxent balloon applicator based on tumor cavity size and shape. A CT image of the implanted balloon was utilized for developing both eBx and Ir-192 brachytherapy treatment plans. The prescription dose was 3.4 Gy per fraction for 10 fractions to be delivered to 1 cm beyond the balloon surface. Iridium plans were provided by the sites on 35 of the 44 patients enrolled in the study. The planning target volume coverage was very similar when comparing sources for each patient as well as between patients. There were no statistical differences in mean %V100. The percent of the planning target volume in the high dose region was increased with eBx as compared with Iridium (p < 0.001). The mean maximum calculated skin and rib doses did not vary greatly between eBx and Iridium. By contrast, the doses to the ipsilateral lung and the heart were significantly lower with eBx as compared with Iridium (p < 0.0001). The total nominal dwell times required for treatment can be predicted by using a combination of the balloon fill volume and planned treatment volume (PTV). This dosimetric comparison of eBx and Iridium sources demonstrates that both forms of balloon-based brachytherapy provide comparable dose to the planning target volume. Electronic brachytherapy is significantly associated with increased dose at the surface of the balloon and decreased dose outside the PTV, resulting in significantly increased tissue sparing in the heart and ipsilateral lung.


Assuntos
Braquiterapia/instrumentação , Neoplasias da Mama/radioterapia , Mama/efeitos da radiação , Elétrons , Coração/efeitos da radiação , Radioisótopos de Irídio/uso terapêutico , Pulmão/efeitos da radiação , Feminino , Humanos , Imagens de Fantasmas , Radiometria , Dosagem Radioterapêutica
7.
Addict Behav ; 99: 106078, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31430619

RESUMO

The association between cigarette use and depression has been documented in many studies. Fewer studies have examined other tobacco products such as electronic cigarettes (e-cigarettes) and hookah that are used by young adults. This study examined whether increased frequency of use of these products was associated with depressive symptoms in a cohort of n = 5236 Texas college students followed from 2014 to 2017. To analyze the longitudinal data, a hierarchical model was used. Model results showed that increased frequency of single product use of cigarettes, refillable e-cigarettes and hookah was associated with depressive symptoms. Refillable and disposable e-cigarettes were examined separately and results did not provide evidence of a different association for each type of e-cigarette when cigarettes were not also used. Dual use of cigarettes with another product was also examined. Dual use was associated with higher depressive symptoms for most product combinations. However, infrequent dual use of disposable e-cigarettes and cigarettes may not be associated with depressive symptoms. Suggestions for further research are included.


Assuntos
Fumar Cigarros/epidemiologia , Depressão/epidemiologia , Vaping/epidemiologia , Fumar Cachimbo de Água/epidemiologia , Adolescente , Fumar Cigarros/psicologia , Depressão/psicologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Texas/epidemiologia , Fumar Tabaco/epidemiologia , Fumar Tabaco/psicologia , Uso de Tabaco/epidemiologia , Uso de Tabaco/psicologia , Tabaco sem Fumaça , Vaping/psicologia , Fumar Cachimbo de Água/psicologia , Adulto Jovem
8.
Chem Commun (Camb) ; (46): 7107-9, 2009 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-19920998

RESUMO

A PEG based 3D hydrogel slide was developed specifically for small-molecule microarraying purposes, which displayed improved loading capacity, signal sensitivity and spot morphology compared with a commercially available slide and comparative 2D slide.


Assuntos
Desenho de Equipamento , Análise Serial de Proteínas/instrumentação , Hidrogel de Polietilenoglicol-Dimetacrilato , Teste de Materiais , Métodos , Polietilenoglicóis
9.
J Neurobiol ; 65(3): 304-19, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16187307

RESUMO

The nervous system of C. elegans has a remarkable abundance of flp genes encoding FMRFamide-like (FLP) neuropeptides. To provide insight into the physiological relevance of this neuropeptide diversity, we have tested more than 30 FLPs (encoded by 23 flps) for bioactivity on C. elegans pharynx. Eleven flp genes encode peptides that inhibit pharyngeal activity, while eight flp genes encode peptides that are excitatory. Three potent peptides (inhibitory, FLP-13A, APEASPFIRFamide; excitatory, FLP-17A, KSAFVRFamide; excitatory, FLP-17B, KSQYIRFamide) are encoded by flp genes, which, according to reporter gene constructs, are expressed in pharyngeal motoneurons. Thus, they may act through receptors localized on the pharyngeal muscle. The two other potent peptides, FLP-8 (excitatory AF1, KNEFIRFamide,) and FLP-11A (inhibitory, AMRNALVRFamide), appear to be expressed in extrapharyngeal neurons and are therefore likely to act either indirectly or as neurohormones. Intriguingly, a single neuron can express peptides that have potent but opposing biological activity in the pharynx. Only five flp genes encode neuropeptides that have no observable effect on the pharynx, but none of these have shown reporter gene expression in the pharyngeal nervous system. To examine the roles of multiple peptides produced from single precursors, a comparison was made between the bioactivity of different neuropeptides for five flp genes (flp-3, flp-13, flp-14, flp-17, and flp-18). For all but one gene (flp-14), the effects of peptides encoded by the same gene were similar. Overall, this study demonstrates the impressive neurochemical complexity of the simple circuit that regulates feeding in the nematode, C. elegans.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , FMRFamida/química , Sistema Nervoso/metabolismo , Neurônios/fisiologia , Neuropeptídeos/fisiologia , Faringe/citologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Caenorhabditis elegans , Relação Dose-Resposta a Droga , Eletrofisiologia/métodos , Modelos Neurológicos , Sistema Nervoso/citologia , Neurônios/classificação
10.
Environ Sci Technol ; 37(18): 4199-204, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-14524453

RESUMO

In this work, theoretical rate constants are estimated for mercury oxidation reactions by hydrogen chloride that may occur in the flue gases of coal combustion. Rate constants are calculated using transition state theory at the quadratic configuration interaction (QCI) level of theory with single and double excitations, and are compared to results obtained from density functional theory, both including high level pseudopotentials for mercury. Thermodynamic and kinetic data from the literature are used to assess the accuracy of the theoretical calculations when possible. Validation of the chosen methods and basis sets is based upon previous and current research on mercury reactions involving chlorine. The present research shows that the QCISD method with the 1992 Stevens et al. basis set leads to the most accurate kinetic and thermodynamic results for the oxidation of mercury via chlorine containing molecules. Also, a comparison of the heats of reaction data for a series of mercury oxidation reactions reveals that the density functional method, B3LYP, with the 1997 Stuttgart basis set provides reasonably accurate results for these large systems.


Assuntos
Carvão Mineral , Ácido Clorídrico/química , Mercúrio/química , Modelos Teóricos , Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Previsões , Incineração , Oxirredução
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