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2.
Genome Biol ; 6(7): R60, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15998449

RESUMEN

We report the initial sequencing and comparative analysis of the Macaca mulatta transcriptome. Cloned sequences from 11 tissues, nine animals, and three species (M. mulatta, M. fascicularis, and M. nemestrina) were sampled, resulting in the generation of 48,642 sequence reads. These data represent an initial sampling of the putative rhesus orthologs for 6,216 human genes. Mean nucleotide diversity within M. mulatta and sequence divergence among M. fascicularis, M. nemestrina, and M. mulatta are also reported.


Asunto(s)
Variación Genética , Macaca mulatta , Transcripción Genética , Animales , Algoritmos , Secuencia de Bases , Clonación Molecular , Bases de Datos de Ácidos Nucleicos , Cartilla de ADN , ADN Complementario/genética , Evolución Molecular , Biblioteca de Genes , Macaca fascicularis/genética , Macaca nemestrina/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Homología de Secuencia de Ácido Nucleico , Humanos
3.
Sci Total Environ ; 342(1-3): 119-44, 2005 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15866271

RESUMEN

The Northern Contaminants Program (NCP) baseline monitoring project was established in 1992 to monitor for persistent organic pollutants (POPs) in Arctic air. Under this project, weekly samples of air were collected at four Canadian and two Russian arctic sites, namely Alert, Nunavut; Tagish, Yukon; Little Fox Lake, Yukon; Kinngait, Nunavut; Dunai Island, Russia and Amderma, Russia. Selected POPs, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides, were analyzed in both the gas and particulate phases. This paper summarizes results obtained from this project in the past 5 years. Temporal trends were developed for atmospheric PCBs and OCs observed at Alert using a digital filtration (DF) technique. It was found that trends developed with 5 years of data (1993-1997) did not differ significantly from those determined with 7 years of data (1993-1999). This implies that with the DF technique, long-term trends can still be developed with less than 10 years of data. An acceleration in decline of OC and PCB air concentrations was noted in 1999 for some compounds, although the reason is unknown. Monitoring efforts must continue to assess the effect of this decline on the long-term trends of POPs in the Canadian Arctic. Occasional high trans-/cis-chlordane ratios and heptachlor air concentrations measured at Alert between 1995 and 1997 suggests sporadic fresh usage of chlordane-based pesticides. However, significant decreasing trends of chlordanes along with their chemical signatures has provided evidence that emission of old soil residues is replacing new usage as an important source to the atmosphere. Measurements of OC air concentrations conducted at Kinngait in 1994-1995 and 2000-2001 indicated faster OC removal at this location than at Alert. This may be attributed to the proximity of Kinngait to temperate regions where both biotic and abiotic degradation rates are faster. The PAH concentrations observed at Alert mimic those at mid-latitudes and are consistent with long-range transport to the Arctic, particularly for the lighter PAHs. A decline in particulate PAH was observed, similar to atmospheric sulphate aerosol and can be attributed to the collapse of industrial activity in the former Soviet Union between 1991 and 1995. Spatial comparisons of OC seasonality at Alert, Tagish, Dunai and Kinngait show elevated air concentrations of some compounds in spring. However, elevated spring concentrations were observed for different compounds at different sites. Potential causes are discussed. Further investigation in the atmospheric flow pattern in spring which is responsible for the transport of POPs into the Arctic is required. OC and PCB air concentrations at Alert were found to be influenced by two climate variation patterns, the North Atlantic Oscillation (NAO) and the Pacific North American (PNA) pattern. Planetary atmospheric patterns must be taken into account in the global prediction and modelling of POPs in the future.

4.
Environ Sci Technol ; 36(5): 862-8, 2002 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11918008

RESUMEN

Temperature normalization (TN), multiple linear regression (MLR), and digital filtration (DF) were used to analyze the temporal trends of an atmospheric dataset on organochlorine pesticides (OCs) collected at the Canadian high arctic site of Alert, Nunavut. Details of these techniques have been presented before (Environ. Sci. Technol. 2001, 35, 1303-1311). Both the TN and DF methods revealed that the majority of OC pesticides declined over the 5 years of study, except endosulfan I and several of the pesticide metabolites, including dieldrin and p,p'-DDE. In comparison to studies conducted in the Great Lakes, atmospheric levels in the Arctic were less dependent on temperature, although seasonal variations were apparent. Generally, levels in the winter were lower than during the rest of the year. A notable exception was p,p'-DDE. Many compounds also showed a second minimum in concentrations during June/July and possible explanations are presented to account for this. The estimated first order half-lives for the decline in OC concentrations were generally found to be comparable or slightly longer than those obtained at temperate locations, with the exception of alpha-HCH, which displayed a much longer half-life in the Arctic (approximately 17 yrs). Sporadic increases in heptachlor as well as increases in the ratio of trans- to cis-chlordane suggest episodic input of chlordanes between 1995 and 1997, especially during the winter.


Asunto(s)
Monitoreo del Ambiente , Hidrocarburos Clorados , Insecticidas/análisis , Regiones Árticas , Canadá , Análisis de Regresión , Estaciones del Año , Factores de Tiempo
5.
Environ Sci Technol ; 35(7): 1303-11, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11348061

RESUMEN

A long-term database of weekly air concentrations was examined to establish temporal trends of PCBs in the Arctic atmosphere. Several methods were employed to reduce the intra-annual variability allowing the elucidation of longterm trends for a selection of congeners at Alert located in the Canadian Arctic. These methods included temperature normalization (TN), multiple linear regression (MLR), and digital filtration (DF). Estimation of the slope (m) resulting from the linear regression between the natural logarithm of the partial pressure in air versus reciprocal temperature (In P = m/T + b), required for TN and MLR, proved difficult due to the poor correlation with temperature experienced forthe majority of congeners. Values of m were considerably lower than those obtained from temperate studies, implying that regional air-surface exchange plays a minor role in supporting the observed air concentrations in the Arctic. The lighter congeners generally showed very low slopes, and some even showed positive correlation with 1/T. This might be a result of their relatively fast reaction rates with OH radicals following the onset of 24-h sunlight in spring. Use of DF (in combination with TN and MLR) revealed declining trends for several of the lower chlorinated congeners in the high Arctic atmosphere, with estimated first-order half-lives, t1/2, ranging from approximately 3 to 20 yr. Declining trends of the lower congeners probably reflect falling levels in source regions, as a result of long-range transport to this Arctic site. There were no apparent trends for the higher chlorinated congeners (penta-substituted and above), exceptfor PCB 180, in marked contrast to temperate studies, indicating a lag time for decline between the Arctic and source regions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Bifenilos Policlorados/análisis , Regiones Árticas , Compuestos de Cloro , Radicales Libres/análisis , Temperatura
6.
Health Soc Work ; 14(4): 245-52, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2599482

RESUMEN

Although research shows a prevalence of depression among black as well as white Americans, black Americans do not seek or receive treatment to an equal extent. Social workers should become better educated about depression and develop skills in recognizing this illness. Outreach efforts are needed to increase black Americans' awareness of depression and of the availability of treatment. Through development of ethnically sensitive mental health services and through working relationships with physicians, social workers can contribute to the identification of depressive symptoms, which can help avoid misdiagnosis.


Asunto(s)
Negro o Afroamericano , Trastorno Depresivo/etnología , Cultura , Trastorno Depresivo/terapia , Femenino , Humanos , Masculino , Servicios de Salud Mental/estadística & datos numéricos , Factores Sexuales , Factores Socioeconómicos
7.
Sci Total Environ ; 77(2-3): 95-131, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3071846

RESUMEN

The literature on aldehyde measurement methods was surveyed and critically reviewed to determine which methods would prove most suitable for monitoring personal exposure to a number of aldehyde compounds that have been found in air. A variety of methods was found that were applicable to measurement of specific aldehydes. Some of these were based on instrumental and spectrophotometric analytical methods. Others, based on direct sorption of aldehydes on solid sorbents with subsequent instrumental analysis, were developed and validated only for one or two aldehydes in air. The most promising techniques involved derivatization with one of several available agents (e.g., N-benzylethanolamine, 2,4-dinitrophenylhydrazine) and, most commonly, extraction and analysis using chromatographic (HPLC or GC) instrumentation. Even these, however, were not found to be fully validated methods suitable for the concurrent measurement of several aldehydes.


Asunto(s)
Contaminantes Atmosféricos/análisis , Aldehídos/análisis , Monitoreo del Ambiente/métodos
9.
Child Welfare ; 67(1): 3-14, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3276464

RESUMEN

Counseling services provided to minors without parental knowledge or consent are based on uncertain and often conflicting policies and procedures. This article examines these services from legal and psychological perspectives, explores current agency policies and practices, and makes recommendations with regard to the counseling needs and rights of minors.


Asunto(s)
Defensa del Niño , Consejo , Adolescente , Defensa del Niño/legislación & jurisprudencia , Desarrollo Infantil , Derechos Civiles/legislación & jurisprudencia , Humanos , Consentimiento Informado/legislación & jurisprudencia , Estados Unidos
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