The spatial distribution of an uncultured clade of marine diazotrophic gamma-proteobacteria in the Arabian Sea was investigated by the development of a specific primer pair to amplify an internal fragment of nifH by PCR. These organisms were most readily detected in highly oligotrophic surface waters but could also be found in deeper waters below the nutricline. nifH transcripts originating from this clade were detected in oligotrophic surface waters and, in addition, in the deeper and the more productive near-coastal waters. The nifH sequences most closely related to the unidentified marine bacterial group are from environmental clones amplified from the Atlantic and Pacific Oceans. These findings suggest that these gamma-proteobacteria are widespread and likely to be an important component of the heterotrophic diazotrophic microbial community of the tropical and subtropical oceans.
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http://dx.doi.org/10.1128/AEM.71.4.2079-2085.2005 | DOI Listing |
Radiat Environ Biophys
January 2025
Department of Environmental Health Sciences, #820-11, Slot, Fay W. Boozman College of Public Health, University of Arkansas for Medical Sciences, 4301 W. Markham Str, Little Rock, AR, 72205, USA.
Most studies on the effects of galactic cosmic rays (GCR) have relied on terrestrial irradiation using spatially homogeneous dose distributions of mono-energetic beams comprised of one ion species. Here, we exposed mice to novel beams that more closely mimic GCR, namely, comprising poly-energetic ions of multiple species. Six-month-old male and female C57BL/6J mice were exposed to 0 Gy, 0.
View Article and Find Full Text PDFNanotoxicology
January 2025
Institute of Physics Belgrade, University of Belgrade, Belgrade, Serbia.
In this study, we investigated the cytotoxic effect of highly soluble dextran-coated CeO nanoparticles on human fetal lung fibroblasts MRC-5. We examined individual nanoparticle-treated cells by Raman spectroscopy and analyzed Raman spectra using non-negative principal component analysis and k-means clustering. In this way, we determined dose-dependent differences between treated cells, which were reflected through the intensity change of lipid, phospholipid and RNA-related Raman modes.
View Article and Find Full Text PDFJ Am Plann Assoc
July 2023
Berkeley, California.
Problem Research Strategy And Findings: The 1968 Fair Housing Act required local government recipients of federal money to take meaningful actions to affirmatively further fair housing (AFFH). Current fair housing analysis requirements are copious but do not request an assessment of how land use policies affect the potential for neighborhood integration. A recent California law requires local governments to include AFFH analysis in existing planning processes, and state guidelines encourage the measurement of the spatial distribution of planned sites for low-income housing with respect to opportunity.
View Article and Find Full Text PDFEnviron Epidemiol
February 2025
Department of Epidemiology, University of Washington School of Public Health, Seattle, Washington.
Objective: We examined if racial residential segregation (RRS) - a fundamental cause of disease - is independently associated with air pollution after accounting for other neighborhood and individual-level sociodemographic factors, to better understand its potential role as a confounder of air pollution-health studies.
Methods: We compiled data from eight large cohorts, restricting to non-Hispanic Black and White urban-residing participants observed at least once between 1999 and 2005. We used 2000 decennial census data to derive a spatial RRS measure (divergence index) and neighborhood socioeconomic status (NSES) index for participants' residing Census tracts, in addition to participant baseline data, to examine associations between RRS and sociodemographic factors (NSES, education, race) and residential exposure to spatiotemporal model-predicted PM and NO levels.
Front Public Health
January 2025
Institute of Occupational Health and Environmental Health, School of Public Health, Lanzhou University, Lanzhou, China.
Introduction: The primary aim of this study is to investigate and predict the prevalence and determinants of tuberculosis disease burden in China. Leveraging high-quality data sources and employing a methodologically rigorous approach, the study endeavors to enhance our understanding of tuberculosis control efforts across different regions of China. First, through nationwide spatio-temporal cluster analysis, we summarized the status of tuberculosis burden in various regions of China and explore the differences, thereby providing a basis for formulating more targeted tuberculosis prevention and control policies in different regions; Subsequently, using a time series-based forecasting model, we conducted the first-ever national tuberculosis burden trend forecast to offer scientific guidance for timely adjustments in planning and resource allocation.
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