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It's always been a thrill of mine to watch jaws drop when gardeners see their first purple-berried callicarpa. Even more satisfying, however, is the chance to turn them on to lesser-known, outstanding species of this genus that ar...
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It's always been a thrill of mine to watch jaws drop when gardeners see their first purple-berried callicarpa. Even more satisfying, however, is the chance to turn them on to lesser-known, outstanding species of this genus that are rarely seen in Northwest gardens. But I'm here to report there's only one form of purple beautyberry that truly thrives in temperate climates, the very same one savvy Northwest gardeners already grow: Callicarpa bodinieri 'Profusion' (syn. C. bodinieri var. giraldii 'Profusion').
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We examined survival rates of mule deer (Odocoileus hemionus) Fawns (1 Jan-31 May) and adult (greater than or equal to 1 yr old) females (1 Jun-31 May) from Colorado, Idaho, and Montana to assess the influence of survival on popul...
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We examined survival rates of mule deer (Odocoileus hemionus) Fawns (1 Jan-31 May) and adult (greater than or equal to 1 yr old) females (1 Jun-31 May) from Colorado, Idaho, and Montana to assess the influence of survival on population dynamics over a broad geographic area. Survival rates were estimated from 1,875 radiocollared fawns and 1,536 radiocollared adult female-years. We found significant year-to-year differences in overwinter survival rates of fawns among states (P < 0.001), while annual survival rates of adult females showed less variation across years (P < 0.256). Sampling distributions of survival rates by age class were modeled with the beta-binomial distribution (BBD) and not found different among states (ad F: P = 0.118; fawns: P = 0.856). The mean overwinter survival rate for fawns was 0.444 (SE = 0.033), with SD = 0.217 (SE = 0.019). The mean annual survival rate for adult females was 0.853 (SE = 0.011), with SD = 0.034 (SE = 0.014). All 3 states exhibited differences in body size of fawns at the start of winter across years, and body size was a predictor of overwinter survival (P < 0.001). Fawn sex ratios in December at time of capture were not different from 50:50 (P = 0.729). However, a sex differential in overwinter survival of fawns was observed (P = 0.002), but beta-binomial models of survival distributions were not different between sexes (P = 0.458). Frequencies of 3 categories of proximal causes of fawn mortality (predation, winter malnutrition, other) differed among states (chi 24 = 41.24, P < 0.001). A deterministic model with a mean winter survival rate of 0.444 for fawns and an annual rate of 0.853 for adult females predicted December fawn:doe ratios would have to be at least 66: 100 to maintain population levels. Similarity of mule deer population dynamics across the 3 states suggests similar processes regulate these populations; hence, results from specific study areas are generally more applicable than commonly thought.
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Tuberculosis is one of the chronic human disease and serious public health problem in developing countries all over the world. It is the major cause of morbidity and mortality especially in sub-Saharan Africa. This study aimed to ...
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Tuberculosis is one of the chronic human disease and serious public health problem in developing countries all over the world. It is the major cause of morbidity and mortality especially in sub-Saharan Africa. This study aimed to assess the prevalence and associated risk factors of smear positive pulmonary tuberculosis among tuberculosis suspected patients at private health institutions in Gondar town. A cross sectional study was conducted at private health institutions on 352 suspected patients. Spot morning sputum was collected and examined by Ziehl-Nelson staining technique. Data was processed by SPSS version 20 software. Out of 352 pulmonary suspected patients who gave sputum samples the prevalence of smear positive pulmonary tuberculosis were 19(5.4%). Among these 12(3.41%) were males while the remaining 7(1.99%) were females. The age ranged from 15 to 91 with mean age of 53 years. Age, average monthly income, low educational status, patients with previous history of chronic disease, contact with tuberculosis suspected cases and ingestion of raw milk were more prone to have pulmonary tuberculosis. So to overcome this problem the responsible bodies should participate to increase the awareness of the community for the prevention and control of tuberculosis.
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Abstract The wettest portion of the interior of western North America centers on the mountainous region spanning western Montana, Idaho, British Columbia, and Alberta. Inland ranges there capture the remnants of Pacific storms. St...
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Abstract The wettest portion of the interior of western North America centers on the mountainous region spanning western Montana, Idaho, British Columbia, and Alberta. Inland ranges there capture the remnants of Pacific storms. Steep east–west hydroclimate gradients make the region sensitive to changes in inland-penetrating moisture that may have varied greatly during the Holocene. To investigate potential hydroclimate change, we produced a 7600-yr lake-level reconstruction from Silver Lake, located on the Montana–Idaho border. Ground-penetrating radar profiles and a transect of four shallow-water sediment cores that were dated using radiocarbon dating and tephrachronology revealed substantial changes in moisture through time. An organic-rich mud unit indicating wet and similar to modern conditions prior to 7000 cal yr BP is overlain by an erosional surface signifying drier than modern conditions from 7000–2800 cal yr BP. A subsequent time-transgressive increase in water levels from 2800–2300 cal yr BP is indicated by a layer of late Holocene muds, and is consistent with glacier expansion and increases in the abundance of mesic tree taxa in the region. Millennial-scale trends were likely driven by variations in orbital-scale forcing during the Holocene, but the regional outcomes probably depended upon factors such as the strength of the Aleutian Low, Pacific sea-surface temperature variability, and the frequency of atmospheric rivers over western North America.
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THE SWAT VALLEY of northwestPakistan is emblematic of the di-lemma of "Af-Pak," as South Asiais abbreviated these days in American andEuropean policy circles. The governmentsof Afghanistan and Pakistan are desper-ately fragile, an...
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THE SWAT VALLEY of northwestPakistan is emblematic of the di-lemma of "Af-Pak," as South Asiais abbreviated these days in American andEuropean policy circles. The governmentsof Afghanistan and Pakistan are desper-ately fragile, and they have sought to calmrestive areas that lie outside their controlby co-opting their enemies. In Afghanistan,there have been repeated efforts to reachout to the "moderate Taliban" and integratethem into the national and local govern-ment as a way of reducing violence.
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The petrogenetic models of the lunar crust are built on the returned Apollo and Luna samples collected from limited parts of the lunar nearside that are chemically unusual (i.e., material rich in K, Rare Earth Elements, and P [KRE...
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The petrogenetic models of the lunar crust are built on the returned Apollo and Luna samples collected from limited parts of the lunar nearside that are chemically unusual (i.e., material rich in K, Rare Earth Elements, and P [KREEP]) and not representative of the entire lunar lithologic suite. The lunar Mg-suite is part of this sample collection and ubiquitously has geochemical characteristics indicating the involvement of KREEP in their petrogenesis and seemed to be linked to the Procellarum KREEP Terrain (PKT). However, it is unclear if KREEP is necessary for Mg-suite magmatism or whether Mg-suite magmatism was a global event that occurred without significant KREEP contribution, and thus, Mg-suite rocks outside of the PKT region may exist without containing a significant KREEP signature. Here, we investigate lunar meteorite Northwest Africa (NWA) 10401, an anorthositic troctolitic breccia with a granulitic texture. NWA 10401 shares many characteristics of Apollo Mg-suite rocks: both its bulk rock composition and alumina content, as well as its mineralogy and mineral chemistry, are more consistent with typical Apollo Mg-suite rocks, rather than ferroan anorthosites. In addition, olivine-spinel equilibria calculations indicate that NWA 10401 is consistent with being derived from a common parent to the Apollo Mg-suite troctolites. However, despite these many shared characteristics, NWA 10401 is strongly depleted in REE, starkly separating it from the typical Apollo Mg-suite of the PKT. This indicates that NWA 10401 (and pairs) could represent a Mg-suite component outside the PKT, and thus, KREEP-poor Mg-suite magmatism may have been a global phenomenon on the Moon.
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Sp and Ps converted seismic waves at 93 permanent seismic stations are used to image upper mantle velocity discontinuities across the contiguous United States and portions of southeast Canada and northwest Mexico. Receiver functio...
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Sp and Ps converted seismic waves at 93 permanent seismic stations are used to image upper mantle velocity discontinuities across the contiguous United States and portions of southeast Canada and northwest Mexico. Receiver functions are calculated with frequencydomain deconvolution and migrated with 1D models that account for variations in crustal structure and mantle velocities between stations. Strong positive Ps phases from the Moho are observed and agree well with previous crustal thickness estimates. In the tectonically active western U.S., high amplitude, negative Sp phases are interpreted as the lithosphere-asthenosphere boundary (LAB) at depths of 51-104 km. These phases indicate a large and rapid LAB velocity gradient and are consistent with an anomalously hot asthenosphere that is rich in water or contains partial melt. In the regions of the Phanerozoic southern and eastern U.S where Sp phases are interpretable as the LAB, the discontinuity lies at depths of 75-111 km and is also too sharp to be explained by temperature alone. In contrast,no Sp phases are observed at depths comparable to the base of the thick high velocity lithosphere that lies beneath cratonic North America and certain portions of the Phanerozoic eastern U.S. At these stations, negative Sp phases occur at depths of 59-113 km and are interpreted as the top of a low velocity zone internal to the lithosphere. The absence of an observable LAB discontinuity in regions of thick lithosphere indicates that the LAB velocity gradient is distributed over more than 50-70 km in depth and is consistent with a purely thermal boundary.
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The Northwest Pacific tropical cyclone (TC) intensification is classified into rapid intensification (RI),normal intensification (NI), and slow intensification (SI) categories. The initial location and intensity, the preceding int...
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The Northwest Pacific tropical cyclone (TC) intensification is classified into rapid intensification (RI),normal intensification (NI), and slow intensification (SI) categories. The initial location and intensity, the preceding intensity change, the motion direction, the occurrence month, and the intensification duration time are all found to differ for RI cases compared with NI and SI cases. The dependence of RI, NI, and SI on environmental conditions is further examined statistically by using the intensification rates of named TCs, for the 21-year period 1995-2015,obtained from JTWC best track data, and the environmental conditions derived from the ERA-Interim reanalysis data and GODAS high-resolution global ocean analysis data. It was found that deep-layer and upper-mid vertical wind shear (VWS),upper-level outflow, sea surface temperature (SST), and ocean heat content (OHC) are statistically different among RI, NI, and SI both before and during intensification. RI is enhanced by weaker and decreasing VWS, warmer oceans, and stronger and increasing outflow. In contrast, SI typically occurs with larger and increasing VWS, cooler oceans, and weaker, static outflow. The impacts of low-level VWS and net moisture inflow are only significantly different between RI and SI and between NI and SI, but not between RI and NI. Another key finding is that increased upper-level outflow and decreased VWS are important precursors and hence are possible predictors, of RI onset. The direction of upper-level outflow affects TC intensification, with NW and NE outflow being more favorable for TC RI than SE and SW outflow.
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This paper presents analyses of five tropical disturbances of various types, derived from observations made over the northwest Pacific in August and September of 2008. Various dynamic and thermodynamic products were derived from d...
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This paper presents analyses of five tropical disturbances of various types, derived from observations made over the northwest Pacific in August and September of 2008. Various dynamic and thermodynamic products were derived from dropsonde and airborne Doppler radar data, with the goal of increasing our understanding of tropical cyclogenesis. From these analyses we draw the following tentative conclusions: The formation of a strong midlevel circulation, with its associated cold core at low levels and warm core aloft, greatly aids the spin‐up of a tropical cyclone by changing the vertical mass flux profile of deep convection from top heavy to bottom heavy. This has two effects: (1) the enhancement at low levels of the convergence of mass and hence vorticity, thus aiding the spin‐up of a warm‐core vortex and (2) the suppression of the lateral export of moist entropy by deep convective inflows and outflows from the core of the developing system. This allows the relative humidity to build up, resulting in more intense convection and further development. Our results also suggest that strong horizontal strain rate at middle levels, as measured by a form of the Okubo‐Weiss parameter, is detrimental to tropical cyclogenesis. Not only can such flow tear apart the midlevel vortex, it can also import air with low moist entropy. In our small sample, the Okubo‐Weiss parameter was the best indicator of the potential for development. Vertical shear appeared to play a less important role in the systems we investigated.
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Water resources in the Pacific Northwest (PNW) are very sensitive to climate change. There are still big knowledge gaps on how evapotranspiration (ET) varies in responding to changing temperature (T) and precipitation (P) over dif...
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Water resources in the Pacific Northwest (PNW) are very sensitive to climate change. There are still big knowledge gaps on how evapotranspiration (ET) varies in responding to changing temperature (T) and precipitation (P) over different zones in terms of supply and demand regime for ET. Here, we employ the Variable Infiltration Capacity (VIC) hydrologic model and a high-resolution meteorological data set to quantify spatial and seasonal variations of ET and the runoff (R)/precipitation (P) ratio over the PNW and attribute effects of T and P. We evaluate modeled ET and R with eddy covariance measurements, upscaled regional ET, and reconstructed natural streamflow. Simulation results indicate that water-limited (annual potential ET (PET) ≥ P) and energy-limited zones (annual PET < P) have different responses to changing climate. In general, waterlimited zones tend to be more associated with increasing ET and decreasing R/P than do energy-limited regions. With controlled simulation experiments, we document that trends in annual and warm-season ET and R/P are dominantly controlled by P, while in the cool season they are mainly controlled by T. During an entire cycle of the Pacific Decadal Oscillation (1947-2006), the PNW experienced a substantial increase in ET and a decrease in R and R/P under the trends of warming and drying. In this snowmelt-dominated region where warming-induced changes to the snowpack are impacting seasonal freshwater availability, decreases in R/P could further aggravate water scarcity. To reduce uncertainties, high-resolution meteorological data sets and intensive model calibrations and evaluations against ET are required.
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