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Leukemia incidence and benzene air pollution in Portland Oregon
Benzene is a widespread urban pollutant and monitoring results show concentrations are particularly high in Portland, Oregon. Nationally, benzene air pollution is the largest contributor to total cancer risk from air pollutants. We used data from several data sets including: modeled benzene distribution at the census block group level from the Oregon Department of Environmental Quality, ten-year leukemia incidence from the Oregon State Cancer Registry, and demographic data from the U.S. Census to examine the correlation of benzene with acute myeloid leukemia (AML), total myeloid leukemia (TML) and total leukemia subgroups. Modeled benzene values were averaged to census tracts using GIS methods. We performed Poisson regression on data for all census tracts and also aggregated data to quartiles of benzene concentration and modeled exposure to determine incidence rate ratios (IRR). We mapped the distribution of benzene, and agestandardized leukemia rates to examine spatial patterns which may not be evident in statistical analysis.
Our regression results found no significant association between benzene and leukemia at the census tract level. AML IRR was slightly elevated for females at the second, but not the third and fourth quartiles of benzene modeled exposure. We found non-significant elevations in AML IRR for those less than 19 years of age at the second and fourth, but not the third quartiles of benzene modeled exposure. We did not observe a monotonically increasing trend toward higher incidence of leukemia with higher modeled benzene exposure. Nor did we see a tendency toward a stronger association in the myeloid types of leukemia. Similar modeling results were produced for perchloroethylene, a cooccurring air toxin that is not considered a leukemiagen. Although the general spatial pattern of leukemia incidence does not appear visually similar to the benzene distribution, some census tracts near point source emissions of benzene had AML rates in the highest bracket. There were some census tracts with elevated TML in the under 19 year old age group near major highways.
Our overall result shows no association between benzene and leukemia at the census tract level. Census tract level ambient air pollution data such as ours is homogenous within census tract measurement units. Most census tracts in our study area are between one and seven miles across so variability of ambient exposure within a few hundred yards of major roads was not captured in our air pollution data. This misclassification of exposure, along with misclassification of case residence in time and place limits the utility of an ecologic design such as ours to detect small changes in disease incidence. The magnitude of cancer risk from ambient benzene is very small, so any misclassifications of exposure or case residence may render even large datasets incapable of detecting elevated incidence rates. Future efforts to investigate health effects of ambient benzene or other mobile source pollutants could incorporate road and residence location as well as modeled air pollution data at the census tract level to achieve more definitive results
Predicting the Probability of Detecting Organochlorine Pesticides and Polychlorinated Biphenyls in Stream Systems on the Basis of Land Use in the Pacific Northwest, USA
2 p. Review produced for HC 441: Science Colloquium: Willamette River Environmental Health, Robert D. Clark Honors College, University of Oregon , Spring term, 2004
Marsupials (Didelphimorphia).
87 pages : illustrations (some color), maps ; 26 cm.This report is the third in our monographic series on mammalian diversity and Matses ethnomammalogy in the YavariÌ-Ucayali interfluvial region of northeastern Peru. Based on taxonomic analysis of specimens collected in the region, we document the occurrence of 19 species of marsupials in the genera Caluromys, Glironia, Hyladelphys, Marmosa, Monodelphis, Metachirus, Chironectes, Didelphis, Philander, Gracilinanus, and Marmosops. Our principal taxonomic results include the following: (1) we provide a phylogenetic analysis of previously unpublished mitochondrial DNA (mtDNA) sequence data for Caluromys that supports the reciprocal monophyly of all currently recognized species in the genus but reveals substantial heterogeneity in one extralimital taxon; (2) we explain why Marmosa constantiae is the correct name for the southwestern Amazonian taxon previously known as Mar. demerarae, and we diagnose Mar. constantiae from Mar. rapposa, a superficially similar species from southern Peru, eastern Bolivia, and central Brazil; (3) we explain why Mar. rutteri is the correct name for one of the Amazonian species currently known as Mar. regina, and we restrict the latter name to the transAndean holotype; (4) we recognize Metachirus myosuros as a species distinct from Met. nudicaudatus based on morphological comparisons and a phylogenetic analysis of new mtDNA sequence data; and (5) we name a new species of Marmosops to honor the late Finnish-Peruvian naturalist Pekka Soini. Of the 19 marsupial species known to occur in the YavariÌ-Ucayali interfluve, 16 have been recorded in sympatry at Nuevo San Juan, the Matses village where we based most of our fieldwork from 1995 to 1999. We explain why we believe the marsupial species list from Nuevo San Juan to be complete (or nearly so), and we compare it with a species list obtained by similarly intensive fieldwork at Paracou (French Guiana). Although Nuevo San Juan and Paracou are 2500 km apart on opposite sides of Amazonia, the same opossum genera are present at both sites, the lists differing only in the species represented in each fauna. We briefly discuss current explanations for spatial turnover in species of terrestrial vertebrates across Amazonian landscapes and provide evidence that the upper Amazon is a significant dispersal barrier for marsupials. Marsupials are not important to the Matses in any way. In keeping with their cultural inattention to mammals that are inconspicuous, harmless, and too small to be of dietary significance, the Matses lexically distinguish only a few kinds of opossums, and they are not close observers of opossum morphology or behavior
Trajectory Model Validation Using Newly Developed Altitude-Controlled Balloons During the International Consortium for Atmospheric Research on Transport and Transformations 2004 Campaign
During the summer of 2004, five altitude-controlled tracking balloons were flown as part of the International Consortium for Atmospheric Research on Transport and Transformations (ICARTT) campaign. These Controlled Meteorological (CMET) balloons, newly developed at the University of Massachusetts, are notable for their light weight (âŒ1 kg mass), efficient altitude control, case of launch, long-duration flight capability, and ability to perform repeated quasi-Lagrangian soundings. The balloons were embedded in urban plumes from New York and Boston which they tracked over New England, eastern Canada, and the Atlantic Ocean while maintaining a nearly constant altitude. The flights ranged from 10 to 111 hours and covered a maximum distance of 3000 km. Balloon flight tracks are used here to assess the accuracy of trajectory models during intensive aircraft sampling periods. A new method is presented for increasing the number of available reference trajectories by dividing the balloon flights into shorter segments for statistical analysis. For trajectory durations between 2 and 12 hours, mean trajectory errors are found to be approximately 26% and 34% of the flight distance for ECMWF-based and GFS-based trajectories, respectively. Anomalously large model errors observed during three of the flights are found to be the result of a narrow low-level jet (15 July) and synoptic-scale flow patterns (9 and 10 August). The results from this study should be useful to researchers evaluating the performance of trajectory models and chemical transport models during the ICARTT campaign. Complete CMET balloon and model trajectory data sets are available as a supplement to this paper
Evidence for guild structure in hyperdiverse mammalian communities.
43 pages : 1 map ; 26 cm.The ecological mechanisms that sustain high species richness in Neotropical bat communities have attracted research attention for several decades. Although many ecologists have studied the feeding behavior and diets of Neotropical bats on the assumption that food is a limiting resource, other resource axes that might be important for species coexistence are often ignored. Diurnal refugia, in particular, are a crucial resource for bats, many of which exhibit conspicuous morphological or behavioral adaptations to the roost environment. Here we report and analyze information about roost occupancy based on >500 field observations of Amazonian bats. Statistical analyses of these data suggest the existence of distinct groups of species roosting (1) in foliage, (2) exposed on the trunks of standing trees, (3) in cavities in standing trees, (4) in or under fallen trees, (5) beneath undercut earth banks, and (6) in arboreal insect nests; additionally, we recognize other groups that roost (7) in animal burrows, and (8) in rocks or caves. Roosting-guild membership is hypothesized to have a filtering effect on Amazonian bat community composition because some types of roosts are absent or uncommon in certain habitats. Among other applications of our results, cross-classifying bat species by trophic and roosting guilds suggests that the often-reported deficit of gleaning animalivores in secondary vegetation by comparison with primary forest might reflect habitat differences in roost availability rather than food resources. In general, ecological and evolutionary studies of Neotropical bats would be enhanced by considering both trophic- and roosting-guild membership in future analyses, but additional fieldwork will be required to determine the roosting behavior of many data-deficient species
New species of Hsunycteris.
26 pages : illustrations (some color), map ; 26 cm.A new species of the nectarivorous bat genus Hsunycteris is described from lowland Amazonian forest in northeastern Peru. The new species, H. dashe, can be distinguished from other congeners by its larger size; V-shaped array of dermal chin papillae separated by a wide basal cleft; metacarpal V longer than metacarpal IV; broad rostrum; lateral margin of infraorbital foramen not projecting beyond rostral outline in dorsal view; well-developed sphenoidal crest; large outer upper incisors; weakly developed lingual cusp on P5; and well-developed, labially oriented M1 parastyle. A phylogenetic analysis of cytochrome-b sequence data indicates that H. dashe is sister to a clade that includes all other species of the genus including H. cadenai, H. pattoni, and a paraphyletic H. thomasi. We provide a key based on craniodental and external characters of all four known species of Hsunycteris
Residential proximity to traffic and female pubertal development
Traffic-related air pollution (TRAP) has been linked with several adverse health outcomes, including preterm birth and low birth weight, which are both related to onset of puberty. No studies to date have investigated the association between TRAP and altered pubertal timing
Fractal dimensions of the Q-state Potts model for the complete and external hulls
Fortuin-Kastelyn clusters in the critical -state Potts model are
conformally invariant fractals. We obtain simulation results for the fractal
dimension of the complete and external (accessible) hulls for Q=1, 2, 3, and 4,
on clusters that wrap around a cylindrical system. We find excellent agreement
between these results and theoretical predictions. We also obtain the
probability distributions of the hull lengths and maximal heights of the
clusters in this geometry and provide a conjecture for their form.Comment: 9 pages 4 figure
Dengue virus-pandemic influenza virus co-infection results in enhanced influenza virus replication through inhibition of apoptosis
Chronic Overlapping Pain Conditions and Long-Term Opioid Treatment
OBJECTIVES: One in 5 people in the United States lives with chronic pain. Many patients with chronic pain experience a subset of specific co-occurring pain conditions that may share a common pain mechanism and that have been designated as chronic overlapping pain conditions (COPCs). Little is known about chronic opioid prescribing patterns among patients with COPCs in primary care settings, especially among socioeconomically vulnerable patients. This study aims to evaluate opioid prescribing among patients with COPCs in US community health centers and to identify individual COPCs and their combinations that are associated with long-term opioid treatment (LOT).
STUDY DESIGN: Retrospective cohort study.
METHODS: We conducted analyses of more than 1 million patients 18 years and older based on electronic health record data from 449 US community health centers across 17 states between January 1, 2009, and December 31, 2018. Logistic regression models were used to assess the relationship between COPCs and LOT.
RESULTS: Individuals with COPCs were prescribed LOT 4 times more often than individuals without a COPC (16.9% vs 4.0%). The presence of chronic low back pain, migraine headache, fibromyalgia, or irritable bowel syndrome combined with any of the other COPCs increased the odds of LOT prescribing compared with the presence of a single COPC.
CONCLUSIONS: Although LOT prescribing has declined over time, it remains relatively high among patients with certain COPCs and for those with multiple COPCs. These study findings suggest target populations for future interventions to manage chronic pain among socioeconomically vulnerable patients
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