727 research outputs found
Drug and Alcohol-Related Workload of Anchorage Patrol Officers: Results From Two Patrol Officer Surveys
It is widely agreed among criminal justice professionals that alcohol and illegal drugs play a role in patterns of crime, but not much is known about how these substances influence the operation of criminal justice agencies, particularly in the area of policing. This report summarizes the findings of a study of the extent to which drug and alcohol-related incidents formed the workload of Anchorage Police Department patrol officers. The study consisted of two surveys, the first of which asked APD patrol officers to provide their best estimate of the amount of time they spent dealing with alcohol and drug-related activities, the second of which required patrol officers to complete incident logs describing drug and alcohol-related incidents encountered on patrol. The study found that officers tended to overestimate the amount of time they spent on drug or alcohol-related activities, but that the drug and alcohol-related activities nonetheless comprise a significant portion of APD patrol officers' workload.Acknowledgements / Executive Summary / List of Tables / List of Figures / Introduction / Methodology / Part I: Survey 1: Global Perceptions of Drug- and Alcohol-related Workload / Part II: Survey 2: Incident-based Perceptions of Drug- and Alcohol-related Workload / Part III: Comparing Officers’ Global Estimates to Incident Log Data / Part IV: Summary and Conclusions / Methodological Appendix / References / Note
Reverse taxonomy for elucidating diversity of insect-associated nematodes: a case study with termites
BACKGROUND: The molecular operational taxonomic unit(MOTU)has recently been applied to microbial and microscopic animal biodiversity surveys. However, in many cases, some of the MOTUs cannot be definitively tied to any of the taxonomic groups in current databases. To surmount these limitations, the concept of "reverse taxonomy" has been proposed, i.e. to primarily list the MOTUs with morphological information, and then identify and/or describe them at genus/species level using subsamples or by re-isolating the target organisms. Nevertheless, the application of "reverse taxonomy" has not been sufficiently evaluated. Therefore, the practical applicability of "reverse taxonomy" is tested using termite-associated nematodes as a model system for phoretic/parasitic organisms which have high habitat specificity and a potential handle (their termite host species) for re-isolation attempts. METHODOLOGY: Forty-eight species (from 298 colonies) of termites collected from the American tropics and subtropics were examined for their nematode associates using the reverse taxonomy method and culturing attempts (morphological identification and further sequencing efforts). The survey yielded 51 sequence types (= MOTUs) belonging to 19 tentatively identified genera. Within these, four were identified based on molecular data with preliminary morphological observation, and an additional seven were identified or characterized from successful culturing, leaving eight genera unidentified. CONCLUSIONS: That 1/3 of the genera were not successfully identified suggests deficiencies in the depth of available sequences in the database and biological characters, i.e. usually isolated as phoretic/parasitic stages which are not available for morphological identification, and too many undiscovered lineages of nematodes. Although there still is the issue of culturability of nematodes, culturing attempts could help to make reverse taxonomy methods more effective. However, expansion of the database, i.e., production of more DNA barcodes tied to biological information by finding and characterizing additional new and known lineages, is necessary for analyzing functional diversity.Natsumi Kanzaki, Robin M. Giblin-Davis, Rudolf H. Scheffrahn, Hisatomo Taki, Alejandro Esquivel, Kerrie A. Davies and E. Allen Herr
Precession of a Freely Rotating Rigid Body. Inelastic Relaxation in the Vicinity of Poles
When a solid body is freely rotating at an angular velocity ,
the ellipsoid of constant angular momentum, in the space , has poles corresponding to spinning about the minimal-inertia and
maximal-inertia axes. The first pole may be considered stable if we neglect the
inner dissipation, but becomes unstable if the dissipation is taken into
account. This happens because the bodies dissipate energy when they rotate
about any axis different from principal. In the case of an oblate symmetrical
body, the angular velocity describes a circular cone about the vector of
(conserved) angular momentum. In the course of relaxation, the angle of this
cone decreases, so that both the angular velocity and the maximal-inertia axis
of the body align along the angular momentum. The generic case of an asymmetric
body is far more involved. Even the symmetrical prolate body exhibits a
sophisticated behaviour, because an infinitesimally small deviation of the
body's shape from a rotational symmetry (i.e., a small difference between the
largest and second largest moments of inertia) yields libration: the precession
trajectory is not a circle but an ellipse. In this article we show that often
the most effective internal dissipation takes place at twice the frequency of
the body's precession. Applications to precessing asteroids, cosmic-dust
alignment, and rotating satellites are discussed.Comment: 47 pages, 1 figur
Vacancies, disorder-induced smearing of the electronic structure, and its implications for the superconductivity of anti-perovskite MgCNi
The anti-perovskite superconductor MgCNi was studied using
high-resolution x-ray Compton scattering combined with electronic structure
calculations. Compton scattering measurements were used to determine
experimentally a Fermi surface that showed good agreement with that of our
supercell calculations, establishing the presence of the predicted hole and
electron Fermi surface sheets. Our calculations indicate that the Fermi surface
is smeared by the disorder due to the presence of vacancies on the C and Ni
sites, but does not drastically change shape. The 20\% reduction in the Fermi
level density-of-states would lead to a significant () suppression
of the superconducting for pair-forming electron-phonon coupling.
However, we ascribe the observed much smaller reduction at our
composition (compared to the stoichiometric compound) to the suppression of
pair-breaking spin fluctuations.Comment: 11 pages, 3 figure
Immunolocalization of KATP channel subunits in mouse and rat cardiac myocytes and the coronary vasculature.
BACKGROUND: Electrophysiological data suggest that cardiac KATP channels consist of Kir6.2 and SUR2A subunits, but the distribution of these (and other KATP channel subunits) is poorly defined. We examined the localization of each of the KATP channel subunits in the mouse and rat heart. RESULTS: Immunohistochemistry of cardiac cryosections demonstrate Kir6.1 protein to be expressed in ventricular myocytes, as well as in the smooth muscle and endothelial cells of coronary resistance vessels. Endothelial capillaries also stained positive for Kir6.1 protein. Kir6.2 protein expression was found predominantly in ventricular myocytes and also in endothelial cells, but not in smooth muscle cells. SUR1 subunits are strongly expressed at the sarcolemmal surface of ventricular myocytes (but not in the coronary vasculature), whereas SUR2 protein was found to be localized predominantly in cardiac myocytes and coronary vessels (mostly in smaller vessels). Immunocytochemistry of isolated ventricular myocytes shows co-localization of Kir6.2 and SUR2 proteins in a striated sarcomeric pattern, suggesting t-tubular expression of these proteins. Both Kir6.1 and SUR1 subunits were found to express strongly at the sarcolemma. The role(s) of these subunits in cardiomyocytes remain to be defined and may require a reassessment of the molecular nature of ventricular KATP channels. CONCLUSIONS: Collectively, our data demonstrate unique cellular and subcellular KATP channel subunit expression patterns in the heart. These results suggest distinct roles for KATP channel subunits in diverse cardiac structures
Design and development of a low temperature, inductance based high frequency ac susceptometer
We report on the development of an induction based low temperature high
frequency ac susceptometer capable of measuring at frequencies up to 3.5 MHz
and at temperatures between 2 K and 300 K. Careful balancing of the detection
coils and calibration have allowed a sample magnetic moment resolution of
at 1 MHz. We will discuss the design and
characterization of the susceptometer, and explain the calibration process. We
also include some example measurements on the spin ice material CdErS
and iron oxide based nanoparticles to illustrate functionality
Nitrogen dynamics in arctic tundra soils of varying age : differential responses to fertilization and warming
Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Oecologia 173 (2013): 1575-1586, doi:10.1007/s00442-013-2733-5.In the northern foothills of the Brooks Range, Alaska, a series of glacial retreats has created a landscape that varies widely in time since deglaciation (= soil age), from ~10k years to more than 2M years. Productivity of the moist tundra that covers most of this landscape is generally N-limited, but varies widely, as do plant-species composition and key soil properties such as pH. These differences might be altered in the future because of the projected increase in N availability under a warmer climate. We hypothesized that future changes in productivity and vegetation composition across soil ages might be mediated through changes in N availability. To test this hypothesis, we compared readily available-N (water-soluble ammonium, nitrate, and amino acids), moderately-available N (soluble proteins), hydrolysable-N, and total-N pools across three tussock-tundra landscapes with soil ages ranging from 11.5k to 300k years. We also compared the effects of long-term fertilization and warming on these N pools for the two younger sites, in order to assess whether the impacts of warming and increased N availability differ by soil age. Readily available N was largest at the oldest site, and amino acids (AA) accounted for 80-89 % of this N. At the youngest site, however, inorganic N constituted the majority (80-97%) of total readily-available N. This variation reflected the large differences in plant functional-group composition and soil chemical properties. Long-term (8-16 years) fertilization increased soluble inorganic N by 20-100 fold at the intermediate-age site, but only by 2-3 fold at the youngest-soil site. Warming caused small and inconsistent changes in the soil C:N ratio and soluble AA, but only in soils beneath Eriophorum vaginatum, the dominant tussock-forming sedge. These differential responses suggest that the impacts of warmer climates on these tundra ecosystems are more complex than simply elevated N mineralization, and that the response of the N cycling might differ strongly depending on the ecosystem’s soil age, initial soil properties, and plant-community composition.Primary financial support came from NSF grant #DEB-0444592 to the MBL, and additional logistical support from NSF-OPP
Western Maine Coastal Current reduces primary production rates, zooplankton abundance and benthic nutrient fluxes in Massachusetts Bay
Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Oxford University Press for personal use, not for redistribution. The definitive version was published in ICES Journal of Marine Science 71 (2014): 1158-1169, doi:10.1093/icesjms/fst195.Primary production was measured from 1992-2010 in Massachusetts Bay
and just outside Boston Harbor for the Massachusetts Water Resources Authority’s
outfall monitoring program. In 2003, annual primary production decreased by 221-278
g C m-2 year-1, with decreased rates continuing through 2010. Based on a conceptual
model, oceanographic and meteorological variables were analyzed with production
rates to determine if concurrent environmental changes were responsible for the
reduced primary production in Massachusetts Bay. Results indicated that stronger
influx of low salinity water from the western Maine Coastal Current (WMCC) in
recent years might be responsible for the decreases. The WMCC appeared to have
become fresher from increased river discharge in the western Gulf of Maine.
Northeasterly winds in recent years promoted WMCC intrusion into Massachusetts
Bay. Correlation between primary production and surface salinities suggested the
impact of the WMCC on production rates. We hypothesized that increased
stratification resulted in reduced vertical mixing and nutrient concentrations in surface
waters for phytoplankton growth. However, no significant correlations were observed
between the annual primary production and nutrient concentrations in Massachusetts
Bay. Reduced production rates in Massachusetts Bay have been associated with
reduced zooplankton abundances, benthic ammonium fluxes and sediment oxygen
demand in summer months.Funding for this work was provided by the MWRA on a contract awarded to
Battelle Ocean Sciences (Project Number 215515), and the National Oceanic and
Atmospheric Administration (Award Number NA05NOS4781201).2015-01-0
Elevated acetate concentrations in the rhizosphere of Spartina alterniflora and potential influences on sulfate reduction
Acetate is important in anaerobic metabolism of non-vegetated sediments but its role in salt marsh soils was not investigated thoroughly. Acetate concentrations, oxidation (C-14) and SO4(2-) reduction (S-35) were measured in S. alterniflora soils in NH and MA. Pore water from cores contained greater than 0.1 mM acetate and in some instances greater than 1.0 mM. Non-destructive samples contained less than 0.01 mM. Acetate was associated with roots and concentrations were highest during vegetative growth and varied with changes in plant physiology. Acetate turnover was very low whether whole core or slurry incubations were used. Radiotracers injected directly into soils yielded rates of SO4(2-) reduction and acetate oxidation not significantly different from core incubation techniques. Regardless of incubation method, acetate oxidation did not account for a significant percentage of SO4(2-) reduction. These results differ markedly from data for non-vegetated coastal sediments where acetate levels are low, oxidation rate constants are high and acetate oxidation rates greatly exceed rates of SO4(2-) reduction. The discrepancy between rates of acetate oxidation and SO4(2-) reduction in marsh soils may be due either to the utilization of substrates other than acetate by SO4(2-) reducers or artifacts associated with measurements of organic utilization by rhizosphere bacteria
- …