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1.
Radiol Case Rep ; 19(2): 763-767, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38074432

RESUMO

Coccidioidomycosis, also known as San Joaquin Valley fever, is an illness caused by the dimorphic fungus Coccidioides. Coccidioidomycosis is endemic to desert regions of the Western Hemisphere, including California, Arizona, Utah, Nevada, and New Mexico. We report a case of disseminated coccidioidomycosis in a 42-year-old male. Months after an upper respiratory infection of unidentified origin, the patient began experiencing back pain. The persistence of the back pain prompted MRI and CT imaging, which revealed lytic lesions. His clinical and radiological presentation mimicked, and was originally approached, as if it were a malignancy. Metastasis or multiple myeloma were considered the most likely differential diagnoses. As a result, the patient underwent surgical exploration. Pathology results indicated the presence of a fungal infection, without evidence of malignancy. PCR confirmed the diagnosis of coccidioidomycosis. The patient began treatment with fluconazole 800 mg daily and is anticipated to receive antifungal treatment for an indefinite period.

2.
Sci Total Environ ; 904: 166937, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37696399

RESUMO

In the southern San Joaquin Valley (SJV) of California, an agriculturally productive region that relies on groundwater for irrigation and domestic water supply, the infiltration of produced water from oil reservoirs is known to impact groundwater due to percolation from unlined disposal ponds. However, previously documented impacts almost exclusively focus on salinity, while contaminant loadings commonly associated with produced water (e.g., radionuclides) are poorly constrained. For example, the infiltration of bicarbonate-rich produced waters can react with sediment-bound uranium (U), leading to U mobilization and subsequent transport to nearby groundwater. Specifically, produced water infiltration poses a particular concern for SJV groundwater, as valley-fill sediments are well documented to be enriched in geogenic, reduced U. Here, we analyzed monitoring well data from two SJV produced water pond facilities to characterize U mobilization and subsequent groundwater contamination. Groundwater wells installed within 2 km of the facilities contained produced water and elevated levels of uranium. There are >400 produced water disposal pond facilities in the southern SJV. If our observations occur at even a fraction of these facilities, there is the potential for widespread U contamination in the groundwaters of one of the most productive agricultural regions in the world.

3.
Environ Sci Technol ; 57(19): 7559-7567, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37146013

RESUMO

Oil and gas development generates large amounts of wastewater (i.e., produced water), which in California has been partially disposed of in unlined percolation/evaporation ponds since the mid-20th century. Although produced water is known to contain multiple environmental contaminants (e.g., radium and trace metals), prior to 2015, detailed chemical characterizations of pondwaters were the exception rather than the norm. Using a state-run database, we synthesized samples (n = 1688) collected from produced water ponds within the southern San Joaquin Valley of California, one of the most productive agricultural regions in the world, to examine regional trends in pondwater arsenic and selenium concentrations. We filled crucial knowledge gaps resulting from historical pondwater monitoring by constructing random forest regression models using commonly measured analytes (boron, chloride, and total dissolved solids) and geospatial data (e.g., soil physiochemical data) to predict arsenic and selenium concentrations in historical samples. Our analysis suggests that both arsenic and selenium levels are elevated in pondwaters and thus this disposal practice may have contributed substantial amounts of arsenic and selenium to aquifers having beneficial uses. We further use our models to identify areas where additional monitoring infrastructure would better constrain the extent of legacy contamination and potential threats to groundwater quality.


Assuntos
Arsênio , Água Subterrânea , Selênio , Poluentes Químicos da Água , Selênio/análise , Poluentes Químicos da Água/análise , Água , Água Subterrânea/análise , Monitoramento Ambiental
4.
Emerg Infect Dis ; 28(9): 1842-1846, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35997543

RESUMO

We conducted a retrospective cohort study that tested 2,000 US military personnel for Coccidioides antibodies in a disease-endemic region. The overall incidence of seroconversion was 0.5 cases/100 person-years; 12.5% of persons who seroconverted had illnesses requiring medical care. No significant association was found between demographic characteristics and seroconversion or disease.


Assuntos
Coccidioidomicose , Militares , California , Coccidioides , Coccidioidomicose/epidemiologia , Coccidioidomicose/etiologia , Humanos , Incidência , Estudos Retrospectivos
5.
Cureus ; 14(2): e21889, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35155039

RESUMO

Coccidoidomycosis is caused by Coccidoides imitis and C. posadasii infection. Coccidioidomycosis is also known as San Joaquin Valley fever or desert rheumatism. It is only seen in the Southwest United States (Arizona, New Mexico, California, Texas, Nevada, and Utah), and Central and South America. This infection is acquired by the inhalation of fungal spores in the air. The most severe extrapulmonary coccidioidomycosis is coccidioidomycosis meningitis, in which patients present with headaches, photophobia, altered mental status, and hearing difficulties. This is a case report of a person with disseminated coccidioidomycosis meningitis complicated by hydrocephalus, presenting as a headache.

6.
Environ Sci Technol ; 55(21): 14782-14794, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34651501

RESUMO

The San Joaquin Valley (SJV) in California is one of the most agriculturally productive regions in the world relying in part on groundwater for irrigation and for domestic or municipal water supply for nearly 4 million residents. One area of growing concern in the SJV is potential impact to groundwater resources from ongoing and historical disposal of oilfield-produced water into unlined produced water ponds (PWPs). In this investigation, we utilized available information on composition of produced water disposed into unlined PWPs and levels of total dissolved solids in underlying groundwater to demonstrate that this disposal practice, both past and present, poses risks to groundwater resources, especially in the Tulare Basin in the southern SJV. Groundwater monitoring at unlined PWP facilities is relatively sparse, but where monitoring has occurred, impact to aquifers used for public and agricultural water supply has been observed and has proven to be too expensive to actively remediate. Results of this investigation should inform policy discussions in California and other locations where disposal of produced water into unlined impoundments occurs, especially at locations that overlie groundwater resources.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , California , Monitoramento Ambiental , Lagoas , Água , Poluentes Químicos da Água/análise , Abastecimento de Água
7.
Cureus ; 13(11): e19980, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34984138

RESUMO

Coccidioidomycosis is a systemic mycosis caused by Coccidioides immitis/posadasii. This dimorphic fungus is endemic to the Southwestern United States, particularly in California and Arizona. Most infections are asymptomatic or mild, but around 5% of patients develop complicated pulmonary infection, and approximately 1% may progress to disseminated disease. We present the case of an adolescent male with Crohn's disease who received the integrin inhibitor, vedolizumab, and developed disseminated coccidioidomycosis. This case underscores the importance of considering severe and/or disseminated coccidioidomycosis in immunosuppressed children. In our case, clinical suspicion and bronchoscopy helped confirm the diagnosis and facilitate appropriate evaluation and treatment.

8.
J Geophys Res Solid Earth ; 125(9): e2020JB019980, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33042724

RESUMO

Large-scale subsidence due to aquifer-overdraft is an ongoing hazard in the San Joaquin Valley. Subsidence continues to cause damage to infrastructure and increases the risk of extensional fissures.Here, we use InSAR-derived vertical land motion (VLM) to model the volumetric strain rate due to groundwater storage change during the 2007-2010 drought in the San Joaquin Valley, Central Valley, California. We then use this volumetric strain rate model to calculate surface tensile stress in order to predict regions that are at the highest risk for hazardous tensile surface fissures. We find a maximum volumetric strain rate of -232 microstrain/yr at a depth of 0 to 200 m in Tulare and Kings County, California. The highest risk of tensile fissure development occurs at the periphery of the largest subsiding zones, particularly in Tulare County and Merced County. Finally, we assume that subsidence is likely due to aquifer pressure change, which is calculated using groundwater level changes observed at 300 wells during this drought. We combine pressure data from selected wells with our volumetric strain maps to estimate the quasi-static bulk modulus, K, a poroelastic parameter applicable when pressure change within the aquifer is inducing volumetric strain. This parameter is reflective of a slow deformation process and is one to two orders of magnitude lower than typical values for the bulk modulus found using seismic velocity data. The results of this study highlight the importance of large-scale, high-resolution VLM measurements in evaluating aquifer system dynamics, hazards associated with overdraft, and in estimating important poroelastic parameters.

9.
J Am Mosq Control Assoc ; 36(3): 208-211, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33600593

RESUMO

Gynandromorphic insects bear both male and female characteristics. In mosquitoes, gynandromorphy has been documented in multiple species and it can include many different combinations of sex-specific traits such as plumose or filiform antennae, short or elongated palpi, and male or female terminalia. Here we report 4 gynandromorphic specimens of Culex erythrothorax, Cx. pipiens complex, Cx. tarsalis, and Culiseta incidens collected in the Northern San Joaquin Valley of California. Each of the specimens exhibited heads with female characteristics of short palpi and filiform antennae while displaying fully developed external male terminalia including basistyles and dististyles. The potential implication of gynandromorphism in genetic control of mosquito vectors is discussed.


Assuntos
Culicidae/anatomia & histologia , Animais , California , Culicidae/crescimento & desenvolvimento , Feminino , Masculino , Caracteres Sexuais , Fatores Sexuais
10.
Insects ; 10(10)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627302

RESUMO

In California's San Joaquin Valley, feeding by the coreid pest, Leptoglossus zonatus, can cause considerable economic loss on almond and pistachio. This research was conducted to improve understanding of how winter temperatures affect mortality of overwintering adult L. zonatus and to develop a better understanding of the role pomegranate plays in the species' life-history. We exposed 7410 field-collected adult L. zonatus to temperatures between -2 and -10 °C for a period of three, four, or six hours using insect incubators. At six hours of exposure, the, LD50 and LD95 occur at -5.8 and -9.7 °C, respectively. We classified L. zonatus as chill-intolerant. Temperatures cold enough to affect substantial mortality of overwintering L. zonatus rarely occur in the San Joaquin Valley. Whole aggregation destructive sampling from a pomegranate hedgerow in Fresno County was conducted to determine population dynamics. At late summer to early fall, aggregations consisted of >90% immature stages. By early to mid-winter, mean aggregation size decreased, consisting of only three to 12 late-instars and adults. During years one and two of the experiment, L. zonatus produced a generation on pomegranate, mostly between September and mid-November. Overwintering did not occur on pomegranate, rather the majority of adults emigrated to other overwintering locations by mid-winter.

11.
Med Mycol ; 57(6): 688-693, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30462288

RESUMO

Coccidioidomycosis, the fungal infection caused by dimorphic Coccidioides species, is typically diagnosed by histopathologic identification of spherules, by culture, or by serology. These tests are reliable but time-intensive, delaying diagnosis and treatment. Rapid real-time polymerase chain reaction (RT-PCR) can be performed and was validated to identify Coccidioides immitis using an in-house developed assay for the Becton Dickinson molecular instrument (BD MAXTM). These studies were performed using patient samples that had been shown to be positive on previously set up fungal cultures. To evaluate this new RT-PCR test in the clinical setting, we conducted a retrospective chart review of patients (N = 1160) who underwent Coccidioides PCR (Cocci PCR) on clinical samples between March 1, 2014, and Dec 31, 2016. We abstracted clinical, microbiologic, serologic, radiographic, treatment, and follow-up data. Specimens of cerebrospinal fluid (CSF), bronchioalveolar lavage fluid (BAL), lung tissue biopsy (LTB), sputum, and pleural fluid were evaluated to determine sensitivity and specificity. Of the 113 specimens that tested positive for Cocci PCR, all had clinical disease defined by traditional clinical criteria, yielding 100% specificity. Overall sensitivity was 74% versus 46% for fungal culture and was available in 4 hours rather than 1-2 weeks. Sensitivities varied by source material and clinical setting. CSF had a sensitivity of 59%, BAL for acute pneumonia 91%, sputum for acute pneumonia 94%, pleural fluid 86%, but LTB for lung nodules only 44%. Overall positive predictive value (PPV) was 100%, while negative predictive value (NPV) was 96%, but again this varied by specimen and clinical setting. Our experience with clinical testing of >1160 specimens over 2-3 years shows we can utilize this technology to improve our ability to diagnose disease but that the sensitivity varies by specimen source and clinical setting.


Assuntos
Coccidioides/isolamento & purificação , Coccidioidomicose/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , Biópsia , Líquido da Lavagem Broncoalveolar/microbiologia , California , Coccidioidomicose/sangue , Humanos , Pulmão/microbiologia , Pulmão/patologia , Derrame Pleural/microbiologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Escarro/microbiologia
12.
J Asthma ; 56(10): 1037-1048, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30299181

RESUMO

Objective: The San Joaquin Valley (SJV) exceeds the state and national standards for ozone (O3). This study investigates whether short-term exposure to O3 is associated with asthma emergency department (ED) visits. Methods: We identified 1,101 ED visits in June-September of 2015 in SJV, California, who lived within 15 km of active air monitors. Conditional logistic regression models were used to obtain the odds ratio (OR) and 95% confidence interval (CI) associated with an interquartile (IQR) increase in ozone. We explored the potential effect modification by sex (female and male), race (White, Black and Hispanic), age (2-5, 6-18, 19-40, 41-64 and > = 65) and county (Merced, Madera, Kings, Fresno and Kern). Results: An IQR range (18.1 ppb) increase in O3 exposure three days before an asthma attack (lag 3) was associated with a 6.6% [OR: 1.066 (95% CI: 1.032, 1.082)] increase in the odds of having an asthma ED visit. The overall ORs differed across age groups and races/ethnicities, with strongest for children aged 6-18 years [OR: 1.219 (95% CI: 1.159, 1.280)], adults 19-40 years [OR: 1.102 (95% CI: 1.053, 1.154)] and Blacks [OR: 1.159 (95% CI: 1.088, 1.236)], respectively. O3 exposure was not positively associated with asthma ED visits for Whites, while it was for other underrepresented groups. Fresno had the highest number of asthma ED visits and positive association among all five counties. Conclusion: We found that O3 exposure is associated with asthma ED visits in the SJV.


Assuntos
Asma/terapia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Exposição Ambiental/efeitos adversos , Ozônio/efeitos adversos , Estações do Ano , Adolescente , Adulto , Fatores Etários , Poluentes Atmosféricos/efeitos adversos , Asma/diagnóstico , Asma/epidemiologia , California , Criança , Estudos Cross-Over , Bases de Dados Factuais , Progressão da Doença , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Razão de Chances , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Adulto Jovem
13.
Sci Total Environ ; 642: 125-136, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29894872

RESUMO

Total dissolved solids (TDS) concentrations in groundwater tapped for beneficial uses (drinking water, irrigation, freshwater industrial) have increased on average by about 100 mg/L over the last 100 years in the San Joaquin Valley, California (SJV). During this period land use in the SJV changed from natural vegetation and dryland agriculture to dominantly irrigated agriculture with growing urban areas. Century-scale salinity trends were evaluated by comparing TDS concentrations and major ion compositions of groundwater from wells sampled in 1910 (Historic) to data from wells sampled in 1993-2015 (Modern). TDS concentrations in subregions of the SJV, the southern (SSJV), western (WSJV), northeastern (NESJV), and southeastern (SESJV) were calculated using a cell-declustering method. TDS concentrations increased in all regions, with the greatest increases found in the SSJV and SESJV. Evaluation of the Modern data from the NESJV and SESJV found higher TDS concentrations in recently recharged (post-1950) groundwater from shallow (<50 m) wells surrounded predominantly by agricultural land uses, while premodern (pre-1950) groundwater from deeper wells, and recently recharged groundwater from wells surrounded by mainly urban, natural, and mixed land uses had lower TDS concentrations, approaching the TDS concentrations in the Historic groundwater. For the NESJV and SESJV, inverse geochemical modeling with PHREEQC indicated that weathering of primary silicate minerals accounted for the majority of the increase in TDS concentrations, contributing more than nitrate from fertilizers and sulfate from soil amendments combined. Bicarbonate showed the greatest increase among major ions, resulting from enhanced silicate weathering due to recharge of irrigation water enriched in CO2 during the growing season. The results of this study demonstrate that large anthropogenic changes to the hydrologic regime, like massive development of irrigated agriculture in semi-arid areas like the SJV, can cause large changes in groundwater quality on a regional scale.


Assuntos
Monitoramento Ambiental , Água Subterrânea/química , Salinidade , Poluentes da Água/análise , Abastecimento de Água/estatística & dados numéricos , Agricultura , California , Poluentes Químicos da Água
14.
Environ Pollut ; 237: 366-376, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29501999

RESUMO

Two hundred sixty-three fine particulate matter (PM2.5) samples collected on 3-day intervals over a 14-month period at two sites in the San Joaquin Valley (SJV) were analyzed for organic carbon (OC), elemental carbon (EC), water soluble organic carbon (WSOC), and organic molecular markers. A unique source profile library was applied to a chemical mass balance (CMB) source apportionment model to develop monthly and seasonally averaged source apportionment results. Five major OC sources were identified: mobile sources, biomass burning, meat smoke, vegetative detritus, and secondary organic carbon (SOC), as inferred from OC not apportioned by CMB. The SOC factor was the largest source contributor at Fresno and Bakersfield, contributing 44% and 51% of PM mass, respectively. Biomass burning was the only source with a statistically different average mass contribution (95% CI) between the two sites. Wintertime peaks of biomass burning, meat smoke, and total OC were observed at both sites, with SOC peaking during the summer months. Exceptionally strong seasonal variation in apportioned meat smoke mass could potentially be explained by oxidation of cholesterol between source and receptor and trends in wind transport outlined in a Residence Time Analysis (RTA). Fast moving nighttime winds prevalent during warmer months caused local emissions to be replaced by air mass transported from the San Francisco Bay Area, consisting of mostly diluted, oxidized concentrations of molecular markers. Good agreement was observed between SOC derived from the CMB model and from non-biomass burning WSOC mass, suggesting the CMB model is sufficiently accurate to assist in policy development. In general, uncertainty in monthly mass values derived from daily CMB apportionments were lower than that of CMB results produced with monthly marker composites, further validating daily sampling methodologies. Strong seasonal trends were observed for biomass and meat smoke OC apportionment, and monthly mass averages had lowest uncertainty when derived from daily CMB apportionments.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Aerossóis/análise , Biomassa , Carbono/análise , Análise por Conglomerados , Meteorologia , Modelos Químicos , São Francisco , Estações do Ano , Fumaça/análise , Vento
15.
J Asthma ; 55(11): 1253-1261, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29261336

RESUMO

BACKGROUND: California's San Joaquin Valley is a region with a history of poverty, low health care access, and high rates of pediatric asthma. It is important to understand the potential barriers to care that challenge vulnerable populations. OBJECTIVE: The objective was to describe pediatric asthma-related utilization patterns in the emergency department (ED) and hospital by insurance coverage as well as to identify contributing individual-level indicators (age, sex, race/ethnicity, and insurance coverage) and neighborhood-level indicators of health care access. METHODS: This was a retrospective study based on secondary data from California hospital and ED records 2007-2012. Children who used services for asthma-related conditions, were aged 0-14 years, Hispanic or non-Hispanic white, and resided in the San Joaquin Valley were included in the analysis. Poisson multilevel modeling was used to control for individual- and neighborhood-level factors. RESULTS: The effect of insurance coverage on asthma ED visits and hospitalizations was modified by the neighborhood-level percentage of concentrated poverty (RR = 1.01, 95% CI = 1.01-1.02; RR = 1.03, 95% CI = 1.02-1.04, respectively). The effect of insurance coverage on asthma hospitalizations was completely explained by the neighborhood-level percentage of concentrated poverty. CONCLUSIONS: Observed effects of insurance coverage on hospital care use were significantly modified by neighborhood-level measures of health care access and concentrated poverty. This suggests not only an overall greater risk for poor children on Medi-Cal, but also a greater vulnerability or response to neighborhood social factors such as socioeconomic status, community cohesiveness, crime, and racial/ethnic segregation.


Assuntos
Asma/etnologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Pobreza/estatística & dados numéricos , Adolescente , Fatores Etários , California/epidemiologia , Criança , Pré-Escolar , Feminino , Hispânico ou Latino/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Cobertura do Seguro/estatística & dados numéricos , Seguro Saúde/estatística & dados numéricos , Masculino , Características de Residência/estatística & dados numéricos , Estudos Retrospectivos , Fatores Sexuais , Fatores Socioeconômicos
16.
Microorganisms ; 5(1)2017 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-28300772

RESUMO

Coccidioidomycosis is a fungal infection caused by Coccidioides posadasii and Coccidioides immitis. It is estimated that 150,000 new infections occur in the United States each year. The incidence of this infection continues to rise in endemic regions. There is an urgent need for the development of better therapeutic drugs and a vaccine against coccidioidomycosis. This review discusses the features of host innate and adaptive immune responses to Coccidioides infection. The focus is on the recent advances in the immune response and host-pathogen interactions, including the recognition of spherules by the host and defining the signal pathways that guide the development of the adaptive T-cell response to Coccidioides infection. Also discussed is an update on progress in developing a vaccine against these fungal pathogens.

17.
CES med ; 30(2): 188-199, jul.-dic. 2016. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-952217

RESUMO

Abstract Coccidioidomycosis is caused by Coccidioides immitis and Coccidioides posadasii fungi, which are endemic in certain locations in the American continent. They produce an asymptomatic infection in the majority of the exposed population, and in a lower proportion, a self-limited influenza-like illness, pneumonia or dissemination. Skin compromise could be secondary to the infection by the fungus or by a hypersensitivity reaction to the pulmonary infection. Primary skin compromise produces a chancriform, self-limited lesion, and the dissemination to the skin commonly produces nodules and abscesses, with a tendency to form fistulas. The most common hypersensitivity reaction is erythema nodosum, which is considered a marker of good prognosis. Treatment depends on the localization of the infection, the presence of dissemination, and the clinical conditions of the patient.


Resumen La coccidioidomicosis es causada por los hongos Coccidioides immitis y Coccidioides posadasii, los cuales son endémicos en determinadas localizaciones del continente americano. Producen infección asintomática en la mayoría de expuestos y en menor proporción cuadros gripales autolimitados, neumonía o diseminación. El compromiso en piel puede ser secundario a la infección por el hongo o por una reacción de hipersensibilidad a la infección pulmonar. El compromiso primario en piel produce una lesión chancreiforme, autolimitada y la diseminación a piel produce comúnmente nódulos y abscesos, con tendencia a la fistulización. La reacción de hipersensibilidad más común es el eritema nodoso, considerándose un marcador de buen pronóstico. El tratamiento depende de la localización de la infección, la presencia de diseminación y las condiciones clínicas del paciente.

18.
Gigascience ; 5(1): 40, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27687002

RESUMO

BACKGROUND: Carrizo Plain National Monument (San Joaquin Desert, California, USA) is home to many threatened and endangered species including the blunt-nosed leopard lizard (Gambelia sila). Vegetation is dominated by annual grasses, and shrubs such as Mormon tea (Ephedra californica), which is of relevance to our target species, the federally listed blunt-nosed leopard lizard, and likely also provides key ecosystem services. We used relatively nonintrusive camera traps, or trail cameras, to capture interactions between animals and these shrubs using a paired shrub-open deployment. Cameras were placed within the shrub understory and in open microhabitats at ground level to estimate animal activity and determine species presence. FINDINGS: Twenty cameras were deployed from April 1st, 2015 to July 5th, 2015 at paired shrub-open microsites at three locations. Over 425,000 pictures were taken during this time, of which 0.4 % detected mammals, birds, insects, and reptiles including the blunt-nosed leopard lizard. Trigger rate was very high on the medium sensitivity camera setting in this desert ecosystem, and rates did not differ between microsites. CONCLUSIONS: Camera traps are an effective, less invasive survey method for collecting data on the presence or absence of desert animals in shrub and open microhabitats. A more extensive array of cameras within an arid region would thus be an effective tool to estimate the presence of desert animals and potentially detect habitat use patterns.

19.
Air Qual Atmos Health ; 9(8): 899-908, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28083077

RESUMO

Despite increasing evidence that airborne polycyclic aromatic hydrocarbon (PAH) exposures contribute to adverse health outcomes for sensitive populations, limited data are available on short-term intraurban spatial distributions for use in epidemiologic research. Exposure assessments for airborne PAHs are uncommon because air sampling for PAHs is a labor-, equipment-, and time-intensive task. To address this gap we measured wintertime PAH concentrations during 2010-2011 in Bakersfield, California, USA, a major city in the Southern San Joaquin Valley. Specifically, 58 96-hour integrated PAH samples were collected during 4 time periods at 14 locations from November 2010 to January 2011; duplicates were collected at two sites. We also collected elemental carbon (EC) at the same 14 sites and analyzed the two time periods with the highest ambient PAH pollution. We used linear regression models to quantify the relationship between potential spatial and temporal predictors of PAH concentrations. We found that wintertime PAH concentrations in Bakersfield, CA, are best predicted by meteorological variables and traffic proximity. Our model explains a moderate amount of the variability in the data (R2=0.58), likely reflecting the major sources of PAHs in Bakersfield. We also observed that PAH concentrations were more spatially variable than EC concentrations. Comparing our data to historical monitoring data at one location in Bakersfield showed that the relatively low PAH concentrations during the 2010-2011 winter in Bakersfield is part of a long-term trend in decreasing PAH concentrations.

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