RESUMO
Here, we report on new data (75 analyses) of plutonium (Pu) isotopes to elucidate activity concentrations, inventories, sources, and their transport from the ocean surface to the seafloor from a collection of six deep-sea sediment cores (depths ranging from 257 to 3739 m) in the southern Gulf of Mexico. Sediment cores collected from the continental shelf and upper slope region of the Gulf of Mexico showed 240Pu/239Pu ratios of 0.15 to 0.26, and 239+240Pu-inventories ranging from 14.7 to 33.0 Bq m-2. Inventories and ratios are consistent with global fallout Pu for this tropical region. In contrast, sediment cores collected from the lower slope region and abyssal plain showed low 240Pu/239Pu ratios of 0.07 to 0.13 and much lower 239+240Pu inventories below 6.8 Bq m-2. This implies that only a small fraction of the expected global fallout Pu has reached the deep-sea sediments. The low 240Pu/239Pu isotope ratios indicate that fallout from the Nevada testing site was an important source of Pu in deep-sea sediments, and that this Pu was likely more efficiently scavenged from the water column than Pu from global fallout. We estimated that up to 44% of the total inventory of 239+240Pu in deep-sea sediments is due to the Nevada source. Low values and a progressive decrease of 240Pu/239Pu ratios and 239+240Pu inventories with increasing water depth have been previously reported for the Gulf of Mexico. Analysis of Pu isotopes in two sediment traps from the upper slope regions shows 240Pu/239Pu ratios comparable to those observed in global fallout. These results indicate that global fallout Pu is currently the main source of Pu in sinking particles in the water column. Therefore, a significant fraction of global fallout Pu must still be present, either in a dissolved phase, or as biologically recycled material in the water column, or scavenged on the shelf and shelf break. Our results bring to light important questions on the application of Pu isotopes to establish sediment chronologies in deep-sea sediments, since global fallout features such as the 1963 maximum are not available.
Assuntos
Plutônio , Monitoramento de Radiação , Cinza Radioativa , Poluentes Radioativos da Água , Plutônio/análise , Poluentes Radioativos da Água/análise , Golfo do México , Água/análise , Nevada , Sedimentos Geológicos/análise , Cinza Radioativa/análiseRESUMO
The study of bio-effects of Schumann resonances is a very complex issue. There is a need to identify mechanisms and pathways that explain how Extremely Low Frequency magnetic fields affect biology or human health. This particular study tries to identify statistical associations between ELF magnetic fields in the province of Granada (Spain) and cardiovascular related hospital admission in the same province for the period April, 1st 2013 to March, 31st 2014. Research is developed under an epidemiological approach based on an Event Coincidence Analysis statistical method. Clustered events, statistically significant (ECA shuffle-surrogate test p = .01 and p < .01), were found for the minimum values of the first and the third Schuman resonances frequency on east-west and north-south directions, and for the amplitude parameter of the second resonance and the total signal energy in the north-south direction. Empirical measurements of SR parameters were recorded at the Sierra Nevada Mountain in Granada province (Spain). Results show a clear coincidence of the events for the minima amplitudes of Shuman resonances and energy in the north-south orientation and the number of the cardiovascular related hospital admissions. Further research is needed with longer temporal series and a new approach based on gender seems to be also interesting for future studies.
Assuntos
Sistema Cardiovascular , Vibração , Humanos , Nevada , EspanhaRESUMO
A new species of Strengeriana Pretzmann, 1971, is described from the El Jardín Natural Reserve, Quindío Department, Colombia, on the western slope of the Central Andes. The genus is endemic to Colombia and is distributed in the Sierra Nevada de Santa Marta, and the Western and Central Andes, at elevations ranging from 700 to 2400 m. With the addition of the new species, Strengeriana now includes 17 species. Strengeriana quindiensis n. sp. is distinguished from its congeners mainly by the exopod of the third maxilliped being 0.92 times the length of the ischium and by the morphology of the first male gonopod, particularly the shapes of the mesial and lateral processes.
Assuntos
Braquiúros , Decápodes , Animais , Colômbia , Água Doce , Masculino , NevadaRESUMO
A new species of Pimelodella is described from northern coastal drainages of the Sierra Nevada de Santa Marta (SNSM), Colombia. The new species is diagnosed from all trans-Andean congeners by the following unique combination of characters: head length 22.2-23.7% SL, bony interorbital width 17.6-21.6% HL, maxillary barbels length 53.0-68.3% SL, inner mental-barbels length 14.4-20.0% SL, body width 17.6-21.1% SL, dorsal-fin spine length 8.3-13.7% SL, dorsal-fin base 12.3-14.9% SL, pectoral-fin spine length 12.9-14.5% SL, pectoral-fin spine length without dentations on the distal posterior margin 21.6-29.8% in pectoral-fin spine length, maximum depth of dentations in posterior margin of pectoral-fin spine 1.40-1.68 times in the width of the spine at its base, adipose-fin base length 22.8-26.4% SL, caudal-peduncle depth 9.2-10.5% SL, 40 vertebrae, having a conspicuous paired dark brown stripe on the dorsal surface of body, extending from posterior margin of head to caudal-fin insertion and a wide dark brown midlateral stripe present. The isolated occurrence of this new taxon living in allopatry in coastal drainages of the SNSM could have interesting biogeographic implications for dispersal and vicariance processes of the ichthyofauna from northern South America.
Assuntos
Peixes-Gato , Animais , Colômbia , Nevada , América do Norte , América do SulRESUMO
St. Louis encephalitis virus (SLEV) and West Nile virus (WNV) have recently emerged in the southwestern United States. Surveillance for arboviruses in Las Vegas, NV, detected a surge of SLEV activity in the southern house mosquito (Culex quinquefasciatus Say) during 2016. To identify candidate avian amplifiers, we assessed the identification, viral infection, and immune status of vertebrate hosts for 195 blood-engorged Cx. quinquefasciatus mosquitoes collected in August and September 2016. Bloodmeals were identified from 164 engorged abdomens, representing 19 species of birds and three species of mammals. No SLEV or WNV viremia was detected, but one mosquito tested positive for Culex flavivirus. House finch (Haemorhous mexicanus) (Muller) was the most common bloodmeal, followed by domestic chicken (Gallus gallus) (Linnaeus), American robin (Turdus migratorius) L., house sparrow (Passer domesticus) (L.), great-tailed grackle (Quiscalus mexicanus) (Gmelin), northern mockingbird (Mimus polyglottos) (L.) and mourning dove (Zenaida macroura) (L.). SLEV-reactive antibodies were detected in six identified bloodmeals and WNV-reactive antibodies were detected in 33. House sparrow and house finch were the most likely hosts to show previous exposure to SLEV and WNV, respectively. Over-utilization by Cx. quinquefasciatus for bloodmeal hosts was observed primarily among robin, finch and sparrow, all species that roost communally. House finch stands out as a candidate important amplifier for both SLEV and WNV because of its preference by mosquito vectors, and high competence for closely related virus strains. While implicated in previous outbreaks as an important mosquito vector, Cx. quinquefasciatus feeds infrequently on mammals in Las Vegas, indicating a low risk for bridge transmission to humans.
Assuntos
Aves , Culex/fisiologia , Vírus da Encefalite de St. Louis/isolamento & purificação , Cadeia Alimentar , Mamíferos , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Culex/virologia , Comportamento Alimentar , Feminino , NevadaRESUMO
The validity of the monobasic neotropical butterfly genus Cheimas Thieme (Nymphalidae, Satyrinae, Satyrini, Pronophilina) is discussed, and confirmed based on morphological and molecular data. Cheimas opalinus (Staudinger), endemic to the Venezuelan Cordillera de Mérida, and considered prior to this study to be monotypic and restricted to the central part of the range, is demonstrated to be polytypic and more widely distributed. Five subspecies are recognised, differing mostly in their dorsal patterns, in particular the shape and colour of hindwing greenish-blue patch. Mitochondrial DNA sequences (COI) were obtained for three of them. The nominate subspecies is found in the central part of the range, in the Sierra Nevada and La Culata. The other subspecies are found as follows: C. opalinus dominici n. ssp.; in the Santo Domingo valley in the centre-north; C. opalinus cristalinus n. ssp. in the north; C. opalinus iosephi n. ssp. on the eastern slopes, and C. opalinus rosalinus n. ssp. in the southern Páramo El Batallón massif. A hybrid zone between the latter two subspecies was detected in the northern part of the Batallón massif based on unusual individual variation and intermediate phenotypes. All the populations of Cheimas opalinus occur in the forest-paramo ecotone at 2800-3400 m a.s.l., with the notable exception of C. opalinus cristalinus n. ssp. found also in mid-elevation forests down to 2300 m a.s.l.
Assuntos
Borboletas , Florestas , Animais , NevadaRESUMO
OBJECTIVE: To study the association between hospital nurse staffing and Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) scores. DATA SOURCES: State hospital financial and utilization reports, Healthcare Cost and Utilization Project State Inpatient Databases, HCAHPS survey, and American Hospital Association Annual Survey of Hospitals. STUDY DESIGN: Retrospective study using cross-sectional and longitudinal models to estimate the effect of nurse staffing levels and skill mix on seven HCAHPS measures. DATA COLLECTION/EXTRACTION METHODS: Hospital-level data measuring nurse staffing, patient experience, and hospital characteristics from 2009 to 2011 for 341 hospitals (977 hospital years) in California, Maryland, and Nevada. PRINCIPAL FINDINGS: Nurse staffing level (i.e., number of licensed practical nurses and registered nurses per 1,000 inpatient days) was significantly and positively associated with all seven HCAHPS measures in cross-sectional models and three of seven measures in longitudinal models. Nursing skill mix (i.e., percentage of all staff who are registered nurses) was significantly and negatively associated with scores on one measure in cross-sectional models and none in longitudinal models. CONCLUSIONS: After controlling for unobserved hospital characteristics, the positive influences of increased nurse staffing levels and skill mix were relatively small in size and limited to a few measures of patients' inpatient experience.
Assuntos
Recursos Humanos de Enfermagem Hospitalar/provisão & distribuição , Satisfação do Paciente/estatística & dados numéricos , Adolescente , Adulto , Idoso , California , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Maryland , Pessoa de Meia-Idade , Nevada , Qualidade da Assistência à Saúde/estatística & dados numéricos , Estudos Retrospectivos , Inquéritos e QuestionáriosRESUMO
In the last decade, the U.S. Food and Drug Administration (FDA) has issued several warnings and recalls for food products that exceed FDA standards for lead. Products containing chili peppers and salt were often suspected as sources of lead contamination, and included items such as candy that are routinely investigated. However, products such as hot sauces that contain similar ingredients have not been the focus of evaluations. This study quantified lead concentrations in imported hot sauces, evaluated product compliance to existing United States standards, and calculated potential dietary lead exposure for children using the Integrated Exposure Uptake Biokinetic Model. Finally, recommendations for reducing the risk of lead exposure from hot sauces are provided. Twenty-five (25) bottles of imported hot sauces manufactured in Mexico and South America were purchased in Clark County, Nevada. All hot sauces were analyzed for lead concentrations, pH, and leaded packaging. Hot sauces were analyzed by inductively coupled plasma mass spectrometry and packaging was analyzed using x-ray fluorescence technology. Four brands of hot sauces (16%) exceeded 0.1 ppm lead, the current FDA action level for lead in candy. Hot sauces with lead concentrations >0.1 ppm lead contained salt and were manufactured in Mexico. Subsequent analysis of additional lots of hot sauces exceeding 0.1 ppm lead revealed inconsistent lead concentrations between and within manufacturer lots. The lead concentrations of the plastic hot sauce lids ranged from below the limit of detection to 2,028 ppm lead. There was no association between lead concentrations in hot sauces and pepper type. These results indicate the need for more rigorous screening protocols for products imported from Mexico, the establishment of an applicable standard for hot sauce, and resources to allow for the enforcement of existing food safety policies. The data reported herein represent the first known investigation of lead concentrations in hot sauces.
Assuntos
Capsicum/química , Contaminação de Alimentos/análise , Chumbo/análise , Capsicum/economia , Qualidade de Produtos para o Consumidor , Contaminação de Alimentos/economia , México , Nevada , América do SulRESUMO
BACKGROUND: Fifty-four outbreaks of domestically acquired typhoid fever were reported between 1960 and 1999. In 2010, the Southern Nevada Health District detected an outbreak of typhoid fever among persons who had not recently travelled abroad. METHODS: We conducted a case-control study to examine the relationship between illness and exposures. A case was defined as illness with the outbreak strain of Salmonella serotype Typhi, as determined by pulsed-field gel electrophoresis (PFGE), with onset during 2010. Controls were matched by neighborhood, age, and sex. Bivariate and multivariate statistical analyses were completed using logistic regression. Traceback investigation was completed. RESULTS: We identified 12 cases in 3 states with onset from 15 April 2010 to 4 September 2010. The median age of case patients was 18 years (range, 4-48 years), 8 (67%) were female, and 11 (92%) were Hispanic. Nine (82%) were hospitalized; none died. Consumption of frozen mamey pulp in a fruit shake was reported by 6 of 8 case patients (75%) and none of the 33 controls (matched odds ratio, 33.9; 95% confidence interval, 4.9). Traceback investigations implicated 2 brands of frozen mamey pulp from a single manufacturer in Guatemala, which was also implicated in a 1998-1999 outbreak of typhoid fever in Florida. CONCLUSIONS: Reporting of individual cases of typhoid fever and subtyping of isolates by PFGE resulted in rapid detection of an outbreak associated with a ready-to-eat frozen food imported from a typhoid-endemic region. Improvements in food manufacturing practices and monitoring will prevent additional outbreaks.
Assuntos
Frutas/microbiologia , Mammea/imunologia , Salmonella typhi/isolamento & purificação , Febre Tifoide/epidemiologia , Adolescente , Adulto , Bebidas/microbiologia , California/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Busca de Comunicante , Surtos de Doenças , Feminino , Microbiologia de Alimentos , Guatemala , Hispânico ou Latino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Nevada/epidemiologia , Oregon/epidemiologia , Fatores de Risco , Salmonella typhi/classificação , Salmonella typhi/genética , Inquéritos e Questionários , Febre Tifoide/etnologia , Febre Tifoide/microbiologiaRESUMO
White American cultural values of appearance are implicated in the development of body dissatisfaction. This study examined whether the relationships between awareness of White American appearance ideals, internalization of such ideals, and body dissatisfaction are moderated by behavioral acculturation and attitudinal marginalization in a sample of 94 Mexican American women. Results indicated that behavioral acculturation moderated the relationship between awareness and internalization and cognitive marginalization moderated the relationship between internalization and body dissatisfaction. Body size was positively correlated with body dissatisfaction and negatively correlated with behavioral acculturation. These findings have important implications for clinical practice and research with Mexican American women.