Artículos de revistas: "Km 20 Community"

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I Namin, J. y P. Spurný. "Fish community structure of the middle course of the Bečva River". Czech Journal of Animal Science 49, No. 1 (11 de diciembre de 2011): 43–50. http://dx.doi.org/10.17221/4270-cjas.

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Fish communities of the Bečva River were studied in summer and autumn 2000 and 2001. Electric fishing gear (Honda EX 1000, DC 230 V, 0.75–0.9 kW) was used for sampling. Four sampling sites (Grymov 19.6 r. km, Rybáře 35.8 r. km, Hustopeče 50.7 and Choryně 54.7 r. km) were selected. Total of 23 fish species representing 5 families were determined. The family Cyprinidae with 15 species was dominant while Salmonidae, Balitoridae, Percidae and Gadidae were the other recorded families. Species diversity ranged from 9 at Hustopeče to 20 at Grymov localities. The lowest biomass and abundance were observed at Hustopeče locality (28.93 kg/ha and 336 fishes/ha) and the highest at Choryně locality (612.90 kg/ha and 7 367 fishes/ha). Barbus barbus, Chondrostoma nasus and Leuciscus cephalus contributed 87.73–97.55% and 60.5%–87% to total biomass and abundance in different samplings, respectively. The Chondrostoma nasus population was dominated by fish of total length over 300 mm. We believe that river fragmentation, trapping and blockade of fish are the main reasons for this irregular distribution. Index of diversity ranged from 0.811 to 2.05 and equitability index from 0.449 to 0.821. Physical and chemical parameters were also measured, pH value ranged from 7.8 to 9.8, DO (7.62–12.15 mg/l), conductivity (450–639 µS/cm), N-NH4 (0.65–2.39 mg/l), P-PO4 (0.12–0.68 mg/l)and alkalinity (2.55 to 3.40 mg/l).

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Jacob, Benjamin, Denis Loum, Denis Munu, Thomson Lakwo, Edson Byamukama, Peace Habomugisha, Eddie W. Cupp y Thomas R. Unnasch. "Optimization of Slash and Clear Community-Directed Control of Simulium damnosum Sensu Stricto in Northern Uganda". American Journal of Tropical Medicine and Hygiene 104, n.º 4 (7 de abril de 2021): 1394–403. http://dx.doi.org/10.4269/ajtmh.20-1104.

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ABSTRACTOnchocerciasis, caused by infection with Onchocerca volvulus, has been targeted for elimination by 2030. Currently, onchocerciasis elimination programs rely primarily on mass distribution of ivermectin. However, ivermectin alone may not be sufficient to achieve elimination in some circumstances, and additional tools may be needed. Vector control has been used as a tool to control onchocerciasis, but vector control using insecticides is expensive and ecologically detrimental. Community-directed removal of the trailing vegetation black fly larval attachment sites (slash and clear) has been shown to dramatically reduce vector biting densities. Here, we report studies to optimize the slash and clear process. Conducting slash and clear interventions at Simulium damnosum sensu stricto breeding sites located within 2 km of afflicted communities resulted in a 95% reduction in vector biting. Extending slash and clear further than 2 km resulted in no further decrease. A single intervention conducted at the first half of the rainy season resulted in a 97% reduction in biting rate, whereas an intervention conducted at the end of the rainy season resulted in a 94% reduction. Vector numbers in any of the intervention villages did not fully recover by the start of the following rainy season. These results suggest that slash and clear may offer an inexpensive and effective way to augment ivermectin distribution in the effort to eliminate onchocerciasis in Africa.

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Thiollay, Jean-Marc. "Structure, density and rarity in an Amazonian rainforest bird community". Journal of Tropical Ecology 10, n.º 4 (noviembre de 1994): 449–81. http://dx.doi.org/10.1017/s0266467400008154.

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ABSTRACTA 100-ha quadrat of primary rainforest in French Guiana was ccnsused over two consecutive years by the mapping method, and a 24-ha core area was intensively mistnetted at the same time. More extensive surveys were conducted in successively larger areas including up to a large part of the forested interior of the country. From a total of 441 resident species found in the rainforest zone, 248 were regularly recorded within the 100-ha plot, 157 of which had mean densities of more than 1 pair km-2. The total estimated density of birds was at least 829 pairs km-2. Only two dominant species exceeded 20 pairs km-2, while 52% of all the species were represented by less than 2 pairs km-2. The distribution of body masses and niche characteristics among the bird community is given as well as the sample bias of the mistnet captures.Rare species were a key component of this primary rainforest community. Several patterns of rarity were described and no marked and constant relationships were found between rarity and body size, habitat, diet, foraging behaviour or social system. Among a wide set of environmental constraints, the population of each species may be limited by a different combination of factors. Habitat heterogeneity, low, irregular and seasonal food availability, interspecific competition or heavy predation pressure were prominent and likely causes of the low density of most species which in turn facilitated the high species richness.

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Tisnawati, Endah y Desrina Ratriningsih. "PENGEMBANGAN KONSEP PARIWISATA SUNGAI BERBASIS MASYARAKAT ; Studi Kasus: Kawasan Bantaran Sungai Gadjah Wong Yogyakarta". Jurnal Arsitektur KOMPOSISI 11, n.º 5 (18 de septiembre de 2017): 189. http://dx.doi.org/10.24002/jars.v11i5.1293.

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Abstract: Gajah Wong River is one of three rivers that pass through the city of Yogyakarta in the east, the length is 20 km. This river entered the city of Yogyakarta through the District Umbulharjo and Kotagede District. Gajah Wong riverside region has great potential as a river tourism area. This paper describes the effort to develop the river area into a community-based tourism area. The method used is qualitative. As a result, the diversity of river attractions, access to the area, and community participation has the potential to increase the attractiveness of the riverside area as a riverside tourism area to create community welfare.Keywords: river tourism, community-basedAbstrak: Sungai Gajah Wong merupakan salah satu dari tiga sungai yang melintas di Kota Yogyakarta di bagian timur, panjangnya 20 km. Sungai ini menembus Kota Yogyakarta melalui Kecamatan Umbulharjo dan Kecamatan Kotagede. Kawasan bantaran sungai Gajah Wong menyimpan potensi besar sebagai wisata sungai. Tulisan ini memaparkan upaya pengembangan kawasan sungai menjadi kawasan wisata berbasis masyarakat. Metode yang digunakan adalah kualitatif. Hasilnya, keragaman aktraksi sungai, akses ke kawasan, dan partisipasi masyarakat berpotensi meningkatkan daya tarik kawasan sebagai kawasan wisata sungai untuk menciptakan kemakmuran masyarakat.Kata Kunci: wisata sungai, berbasis masyarakat.

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Shephard, Samuel, Hans D. Gerritsen, Michel J. Kaiser, Holly S. Truszkowska y David G. Reid. "Fishing and environment drive spatial heterogeneity in Celtic Sea fish community size structure". ICES Journal of Marine Science 68, n.º 10 (20 de agosto de 2011): 2106–13. http://dx.doi.org/10.1093/icesjms/fsr137.

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Abstract Shephard, S., Gerritsen, H. D., Kaiser, M. J., Truszkowska, H. S., and Reid, D. G. 2011. Fishing and environment drive spatial heterogeneity in Celtic Sea fish community size structure. – ICES Journal of Marine Science, 68: 2106–2113. The Large Fish Indicator (LFI) is a univariate size-based indicator of fish community state that has been selected to support the OSPAR fish community Ecological Quality Objective (EcoQO). To operate this EcoQO, a survey-based LFI for each OSPAR region needs to be developed. However, fish communities in these regions are spatially heterogeneous, and there is evidence of within-region spatial variation in the LFI that could confound an overall indicator series. For Celtic Sea trawl-survey sites, spline correlograms indicate positive spatial autocorrelation at a similar range (∼40 km) for the LFI and for fishing effort (h year−1) from vessel monitoring systems. Statistical models reveal a strong negative effect on annual LFI by site of fishing effort within a radius of 40 km. There was a weak effect of fishing within 20 km and no effect at 10 km. LFI also varied significantly with substratum and with local fish community composition identified by a resemblance matrix derived from the survey data. Finally, there was a weak effect of survey year on LFI. Spatial stratification of LFI calculations may be necessary when developing size-based indicators for OSPAR or Marine Strategy Framework Directive regions.

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Greve, Ralf y Ute C. Herzfeld. "Resolution of ice streams and outlet glaciers in large-scale simulations of the Greenland ice sheet". Annals of Glaciology 54, n.º 63 (2013): 209–20. http://dx.doi.org/10.3189/2013aog63a085.

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AbstractThe dynamic/thermodynamic shallow-ice model SICOPOLIS is applied to the Greenland ice sheet. Paleoclimatic spin-ups from 125 ka BP until today, as well as future-climate experiments 500 years into the future, are carried out with three different grid spacings, namely 20, 10 and 5 km. The scenarios are a subset of those specified by the SeaRISE (Sea-level Response to Ice Sheet Evolution) community effort. The bed topography includes improved troughs for Jakobshavn Isbræ, Helheim, Kangerdlugssuaq and Petermann glaciers, processed by an algorithm that preserves shape, orientation and continuity of the troughs on the 5 km scale. Comparison of simulated and observed present-day surface velocities shows that these ice streams and outlet glaciers are resolved with different accuracies, ranging from poor (20 km grid) to reasonably good (5 km grid). In the future-climate experiments, the simulated absolute ice volumes depend significantly on the resolution, while the sensitivities (ice volumes relative to the constant-climate control run) vary only by a few centimeters of sea-level equivalent.

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Gualie, Yilkal T. y Habtamu D. Enyew. "Estimating access to drinking water supply in Farta district rural community, Amhara Region, North Central Ethiopia, 2017: a community based cross-sectional study". International Journal of Scientific Reports 5, n.º 9 (23 de agosto de 2019): 240. http://dx.doi.org/10.18203/issn.2454-2156.intjscirep20193762.

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Background: Water is an essential for lives and development. Ethiopia is endowed with enormous water resources potential but access to water is limited. An uneven spatial distribution of water sources and drinking water demand is big challenge. Therefore objectives of this study were to estimate access for water supply among household of Farta district, Ethiopia.Methods: A community based cross-sectional study design was employed in 758 households of Farta district. Interview and observational check lists were used to collect data. Systematic sampling technique was used to select households. Data was analyzed using SPSS version 20 software. Results: The community has access to improved water supply which was estimated to be 57.1%. The rest 42.9% of the households used unimproved water sources from other unprotected sources like unprotected dug well and river. Nearly the third quartile (74.5%) of the households had access to water within a distance of 1.5 km or less from dwelling. Majority (86%) of households had no access to water within a time of 30 minutes or less. Nearly 92.3% of the households used less than 20 liters per capita per day.Conclusions: There was a significant gap in accessing water supply for the community within 1.5 km in the district. Nearly half of households used protected well water sources. The per capita water consumption of the households were extremely low. Hence local administrator should expand protected well in all members. The community participation should be encouraged to prepare and maintain the water sources.

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Appel, K. W., K. M. Foley, J. O. Bash, R. W. Pinder, R. L. Dennis, D. J. Allen y K. Pickering. "A multi-resolution assessment of the Community Multiscale Air Quality (CMAQ) Model v4.7 wet deposition estimates for 2002–2006". Geoscientific Model Development Discussions 3, n.º 4 (9 de diciembre de 2010): 2315–60. http://dx.doi.org/10.5194/gmdd-3-2315-2010.

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Abstract. This paper examines the operational performance of the Community Multiscale Air Quality (CMAQ) model simulations for 2002–2006 using both 36-km and 12-km horizontal grid spacing with a primary focus on the performance of the CMAQ model in predicting wet deposition of sulfate (SO4=), ammonium (NH4+) and nitrate (NO3−). Performance of the wet deposition species is determined by comparing CMAQ predicted concentrations to concentrations measured by the National Acid Deposition Program (NADP), specifically the National Trends Network (NTN). For SO4= wet deposition, the CMAQ model estimates were generally comparable between the 36-km and 12-km simulations for the eastern US, with the 12-km simulation giving slightly higher estimates of SO4= wet deposition than the 36-km simulation on average. The normalized mean bias (NMB) was slightly higher for the 12-km simulation, however, both simulations had annual biases that were less than ±15% for each of the five years. The model estimated SO4= wet deposition values improved when they were adjusted to account for biases in the model estimated precipitation. The CMAQ model underestimates NH4+ wet deposition over the eastern US using both the 36-km and 12-km horizontal grid spacing, with a slightly larger underestimation in the 36-km simulation. The largest underestimations occur during the winter and spring periods, while the summer and fall have slightly smaller underestimations of NH4+ wet deposition. Annually, the NMB generally ranges between −10% and −16% for the 12-km simulation and −12% to −18% for the 36-km simulation over the five-year period for the eastern US. The underestimation in NH4+ wet deposition is likely due, in part, to the poor temporal and spatial representation of ammonia (NH3) emissions, particularly those emissions associated with fertilizer applications and NH3 bi-directional exchange. The model performance for estimates of NO3− wet deposition are mixed throughout the year, with the model largely underestimating NO3− wet deposition in the spring and summer in the eastern US, while the model has a relatively small bias in the fall and winter. Model estimates of NO3− wet deposition tend to be slightly lower for the 36-km simulation as compared to the 12-km simulation, particularly in the spring. Annually for the eastern US, the NMB ranges from roughly −12% to −20% for the 12-km simulation and −18% to −26% for the 36-km simulation. The underestimation of NO3− wet deposition in the spring and summer is due, in part, to a lack of lightning generated NO emissions in the upper troposphere, which can be a large source of NO in the spring and summer when lightning activity is the high. CMAQ model simulations that include the production of NO from lightning show a significant improvement in the NO3− wet deposition estimates in the eastern US in the summer. Model performance for the western US was generally not as good as that for the eastern US for all three wet deposition species.

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Jia, Jia, Antti Kero, Niilo Kalakoski, Monika E. Szeląg y Pekka T. Verronen. "Is there a direct solar proton impact on lower-stratospheric ozone?" Atmospheric Chemistry and Physics 20, n.º 23 (4 de diciembre de 2020): 14969–82. http://dx.doi.org/10.5194/acp-20-14969-2020.

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Abstract. We investigate Arctic polar atmospheric ozone responses to solar proton events (SPEs) using MLS (Microwave Limb Sounder) satellite measurements (2004–now) and WACCM-D (Whole Atmosphere Community Climate Model) simulations (1989–2012). Special focus is on lower-stratospheric (10–30 km) ozone depletion that has been proposed earlier based on superposed epoch analysis (SEA) of ozonesonde anomalies (up to 10 % ozone decrease at ∼ 20 km). SEA of the satellite dataset provides no solid evidence of any average SPE impact on the lower-stratospheric ozone, although at the mesospheric altitudes a statistically significant ozone depletion is present. In the individual case studies, we find only one potential case (January 2005) in which the lower-stratospheric ozone level was significantly decreased after the SPE onset (in both model simulation and MLS observation data). However, similar decreases could not be identified in other SPEs of similar or larger magnitude. Due to the input proton energy threshold of > 300 MeV, the WACCM-D model can only detect direct proton effects above 25 km, and simulation results before the Aura MLS era indicate no significant effect on the lower-stratospheric ozone. However, we find a very good overall consistency between WACCM-D simulations and MLS observations of SPE-driven ozone anomalies both on average and for the individual cases including January 2005.

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McClanahan, T. R. y N. A. J. Graham. "Marine reserve recovery rates towards a baseline are slower for reef fish community life histories than biomass". Proceedings of the Royal Society B: Biological Sciences 282, n.º 1821 (22 de diciembre de 2015): 20151938. http://dx.doi.org/10.1098/rspb.2015.1938.

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Ecological baselines are disappearing and it is uncertain how marine reserves, here called fisheries closures, simulate pristine communities. We tested the influence of fisheries closure age, size and compliance on recovery of community biomass and life-history metrics towards a baseline. We used census data from 324 coral reefs, including 41 protected areas ranging between 1 and 45 years of age and 0.28 and 1430 km 2 , and 36 sites in a remote baseline, the Chagos Archipelago. Fish community-level life histories changed towards larger and later maturing fauna with increasing closure age, size and compliance. In high compliance closures, community biomass levelled at approximately 20 years and 10 km 2 but was still only at approximately 30% of the baseline and community growth rates were projected to slowly decline for more than 100 years. In low compliance and young closures, biomass levelled at half the value and time as high compliance closures and life-history metrics were not predicted to reach the baseline. Biomass does not adequately reflect the long-time scales for full recovery of life-history characteristics, with implications for coral reef management.

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Haeberli, Wilfried, Christian Huggel, Andreas Kääb, Sonja Zgraggen-Oswald, Alexander Polkvoj, Igor Galushkin, Igor Zotikov y Nikolay Osokin. "The Kolka-Karmadon rock/ice slide of 20 September 2002: an extraordinary event of historical dimensions in North Ossetia, Russian Caucasus". Journal of Glaciology 50, n.º 171 (2004): 533–46. http://dx.doi.org/10.3189/172756504781829710.

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AbstractOn 20 September 2002, an enormous rock/ice slide and subsequent mud-flow occurred on the northern slope of the Kazbek massif, Northern Ossetia, Russian Caucasus. It started on the north- northeast wall of Dzhimarai-Khokh (4780 ma.s.l.) and seriously affected the valley of Genaldon/ Karmadon. Immediate governmental actions, available scientific information, first reconstructions, hazard assessments and monitoring activities as well as initial expert judgments/recommendations are documented in order to enable more detailed analyses and modelling of the event by the wider scientific community. Among the most remarkable aspects related to this event are (1) the relation between the recent event and somewhat smaller but quite similar events that occurred earlier in historical times (1835, 1902), (2) the interactions between unstable local geological structures and complex geothermal and hydraulic conditions in the starting zone with permafrost, cold to polythermal hanging glaciers and volcanic effects (hot springs) in close contact with each other, (3) the erosion and incorporation of a debris-covered valley glacier largely enhancing the sliding volume of rocks, ice, firn, snow, water and probably air to a total of about 100 × 106m3, and (4) the astonishingly high flow velocities (up to 300 km h-1) and enormous length of travel path (18 km plus 15 km of debris/mud-flow). This extraordinary case illustrates that large catastrophic events in high mountain regions typically involve a multitude of factors and require integrated consideration of complex chains of processes, a task which must be undertaken by qualified groups of experts.

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Palmer, Carol, Guido J. Parra, Tracey Rogers y John Woinarski. "Collation and review of sightings and distribution of three coastal dolphin species in waters of the Northern Territory, Australia." Pacific Conservation Biology 20, n.º 1 (2014): 116. http://dx.doi.org/10.1071/pc140116.

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On a global scale, the coastal waters of the Northern Territory (NT), Australia, are relatively undisturbed, but the pace and extent of coastal development is increasing. Three species of dolphin occur in these waters: the Australian snubfin Orcaella heinsohni, Indo-Pacific humpback Sousa chinensis and bottlenose Tursiops sp., but their distribution is poorly documented. To provide a broader distributional context and complement recent local-scale population studies (Palmer in press), we review the broader distribution of these coastal dolphins, via the collation of historic and contemporary data from sighting surveys, stranding and museum records, and a community sighting programme. Records spanned 1948 to 2010, with Sousa (44%) the most frequently recorded followed by Orcaella and Tursiops (both 28%). The compiled records indicate that the three species are widely distributed along the NT coast but with some apparent differences in habitat use. All species were recorded within 20 km of a major tidal river; but fewer than 3% of Tursiops records were from within tidal rivers, whereas nearly a quarter of Orcaella and Sousa records were as far as 20 to 50 km upstream. Differences in environmental settings between Orcaella and Sousa were less pronounced, but a lower proportion of Orcaella were recorded within 20 km of a river mouth. There are probable but unquantifiable biases in the record sources, but most records of dolphins were from estuaries, tidal rivers and coastal areas within 20 km of river mouths, and these sites probably represent important habitat for these species. The NT’s remote and relatively pristine waters likely hold significant subpopulations of all three species. The information provided here should aid future research efforts, however; further information on the dolphins’ population size, trend and structure are needed to resolve their conservation status at state and national jurisdictions, inform environmental impact assessments and species management.

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Pisanu, Philip, Paul Bayne, Robert Harden y Ann Eggert. "Feral goats (Capra hircus L.) in the Macleay River gorge system, north-eastern New South Wales, Australia. II. Impacts on rainforest vegetation". Wildlife Research 32, n.º 2 (2005): 111. http://dx.doi.org/10.1071/wr03085.

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The impacts of feral goats in rainforests and thickets of the Macleay River system were studied. Rainforest floristics and diversity and goat browsing were measured over five years in a large-scale experiment with two experimental controls (density <1 goat km–2 and density ~20 goats km–2), and a goat-removal treatment (670-ha exclosure, initial density ~20 goats km–2). Feral goats browsed forb, shrub, tree and vine species. Sites with many goats were browsed at significantly higher levels than sites from which goats were removed and sites where goats occurred at very low density (<1 goat km–2). Contrary to findings in other studies, no plant species declined substantially where goat densities remained high throughout the study. Only the native forb Urtica incisa increased markedly following removal of goats. High goat numbers were not linked to increased exotic species abundances. At the community scale, species richness, diversity and evenness did not vary substantially among treatments in any year, nor did ordinations of sites (multidimensional scaling) reveal any pattern of site similarity between years that could be related to either goat presence or absence. Rainfall may have influenced plant density and masked the effects of feral goats. Rainforests in the region appear to be resilient to browsing under present feral goat densities, probably because goats feed predominantly in adjacent grassy woodlands and forests. However, we recommend a precautionary approach to feral goat management as these rainforests and thickets are of high conservation value.

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Monaghan, Andrew J., Michael Barlage, Jennifer Boehnert, Cody L. Phillips y Olga V. Wilhelmi. "Overlapping Interests: The Impact of Geographic Coordinate Assumptions on Limited-Area Atmospheric Model Simulations". Monthly Weather Review 141, n.º 6 (1 de junio de 2013): 2120–27. http://dx.doi.org/10.1175/mwr-d-12-00351.1.

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Abstract There is growing use of limited-area models (LAMs) for high-resolution (<10 km) applications, for which consistent mapping of input terrestrial and meteorological datasets is critical for accurate simulations. The geographic coordinate systems of most input datasets are based on spheroid-shaped (i.e., elliptical) Earth models, while LAMs generally assume a perfectly sphere-shaped Earth. This distinction is often neglected during preprocessing, when input data are remapped to LAM domains, leading to geolocation discrepancies that can exceed 20 km at midlatitudes. A variety of terrestrial (topography and land use) input dataset configurations is employed to explore the impact of Earth model assumptions on a series of 1-km LAM simulations over Colorado. For the same terrestrial datasets, the ~20-km geolocation discrepancy between spheroidal-versus-spherical Earth models over the domain leads to simulated differences in near-surface and midtropospheric air temperature, humidity, and wind speed that are larger and more widespread than those due to using different topography and land use datasets altogether but not changing the Earth model. Simulated differences are caused by the shift of static fields with respect to boundary conditions, and altered Coriolis forcing and topographic gradients. The sensitivity of high-resolution LAM simulations to Earth model assumptions emphasizes the importance for users to ensure terrestrial and meteorological input data are consistently mapped during preprocessing (i.e., datasets share a common geographic coordinate system before remapping to the LAM domain). Concurrently, the modeling community should update preprocessing systems to make sure input data are correctly mapped for all global and limited-area simulation domains.

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Nara, Seidai, Tomohiro O. Sato, Takayoshi Yamada, Tamaki Fujinawa, Kota Kuribayashi, Takeshi Manabe, Lucien Froidevaux et al. "Validation of SMILES HCl profiles over a wide range from the stratosphere to the lower thermosphere". Atmospheric Measurement Techniques 13, n.º 12 (16 de diciembre de 2020): 6837–52. http://dx.doi.org/10.5194/amt-13-6837-2020.

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Abstract. Hydrogen chloride (HCl) is the most abundant (more than 95 %) among inorganic chlorine compounds Cly in the upper stratosphere. The HCl molecule is observed to obtain long-term quantitative estimations of the total budget of the stratospheric chlorine compounds. In this study, we provided HCl vertical profiles at altitudes of 16–100 km using the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) from space. The HCl vertical profile from the upper troposphere to the lower thermosphere is reported for the first time from SMILES observations; the data quality is quantified by comparison with other measurements and via theoretical error analysis. We used the SMILES level-2 research product version 3.0.0. The period of the SMILES HCl observation was from 12 October 2009 to 21 April 2010, and the latitude coverage was 40∘ S–65∘ N. The average HCl vertical profile showed an increase with altitude up to the stratopause (∼ 45 km), approximately constant values between the stratopause and the upper mesosphere (∼ 80 km), and a decrease from the mesopause to the lower thermosphere (∼ 100 km). This behavior was observed in all latitude regions and reproduced by the Whole Atmosphere Community Climate Model in the specified dynamics configuration (SD-WACCM). We compared the SMILES HCl vertical profiles in the stratosphere and lower mesosphere with HCl profiles from Microwave Limb Sounder (MLS) on the Aura satellite, as well as from the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) on SCISAT and the TErahertz and submillimeter LImb Sounder (TELIS) (balloon borne). The TELIS observations were performed using the superconductive limb emission technique, as used by SMILES. The globally averaged vertical HCl profiles of SMILES agreed well with those of MLS and ACE-FTS within 0.25 and 0.2 ppbv between 20 and 40 km (within 10 % between 30 and 40 km; there is a larger discrepancy below 30 km), respectively. The SMILES HCl concentration was smaller than those of MLS and ACE-FTS as the altitude increased from 40 km, and the difference was approximately 0.4–0.5 ppbv (12 %–15 %) at 50–60 km. The difference between SMILES and TELIS HCl observations was about 0.3 ppbv in the polar winter region between 20 and 34 km, except near 26 km. SMILES HCl error sources that may cause discrepancies with the other observations are investigated by a theoretical error analysis. We calculated errors caused by the uncertainties of spectroscopic parameters, instrument functions, and atmospheric temperature profiles. The Jacobian for the temperature explains the negative bias of the SMILES HCl concentrations at 50–60 km.

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Represa, Palomar-Vázquez, Porta y Fernández-Sarría. "Daily Concentrations of PM2.5 in the Valencian Community Using Random Forest for the Period 2008–2018". Proceedings 19, n.º 1 (15 de julio de 2019): 13. http://dx.doi.org/10.3390/proceedings2019019013.

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Fine particulate matter (PM2.5) is a global problem that affects the population health and contributes to climate change. Remote sensing provides useful information for the development of air quality models. This work aims to obtain a daily model of PM2.5 levels in the Valencian Community with a resolution of 1 km for the period 2008–2018. MODIS-MAIAC images, meteorological parameters of the MERRA-2 project, land cover information and ground level measurements of PM2.5 levels were analysed with Random Forest. The verification of the model was carried out using cross-validation repeated ten times, and an evaluation of a test set with 20% of the collected information. The final model was used to generate maps of the daily concentrations of PM2.5 for the area of the Valencian Community throughout the study period.

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Long, L. T., A. Kocaoglu, R. Hawman y P. J. W. Gore. "The Norris Lake Earthquake Swarm of June Through September, 1993; Preliminary Findings". Seismological Research Letters 65, n.º 2 (1 de abril de 1994): 167–71. http://dx.doi.org/10.1785/gssrl.65.2.167.

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Abstract During the summer of 1993, the residents in the Norris Lake community, Lithonia, Georgia, were bothered by an incessant swarm of earthquakes. The largest, a magnitude 2.7 on September 23, showed a normal aftershock decay and occurred after the main swarm. Over 10,000 earthquakes have been detected, of which perhaps 500 were felt. The earthquakes began June 8, 1993, with a 5-day swarm. The residents, accustomed to quarry explosions, suspected the quarries of irregular activities. To locate the source of the events, a visual recorder and a digital event recorder were placed in the epicentral area. Ten to 20 events were detected per day for the next three weeks. The swarm then escalated to a peak of over 100 per day by August 15, 1993. Activity following the peak died down to about 10 events per day. The magnitude 2.7 event of September 23 was followed by a normal aftershock sequence. The larger events were felt with intensity V within 2 km of their epicenter, and noticed (intensity II) to a distance of 15 km. Some incidents of cracked wallboard and foundations have been reported, but no significant damage has been documented. Preliminary locations, based on data from digital event recorders, suggest an average depth of 1.0 km. The hypocenters are in the Lithonia gneiss, a massive migmatite resistant to weathering and used locally as a building stone. The epicenters are 1 to 2 km south-southwest of the Norris Lake Community. The cause of the seismicity is not yet known. The earthquakes are characteristic of reservoir-induced earthquakes; however, Norris Lake is a small (96 acres), 2 to 5m deep recreational lake which has existed since the 1950s.

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Gurubaran, S., D. Narayana Rao, G. Ramkumar, T. K. Ramkumar, G. Dutta y B. V. Krishna Murthy. "First results from the CAWSES-India Tidal Campaign". Annales Geophysicae 26, n.º 8 (5 de agosto de 2008): 2323–31. http://dx.doi.org/10.5194/angeo-26-2323-2008.

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Abstract. The first CAWSES-India Tidal Campaign was conducted by the Indian scientific community during March–April 2006. The objectives of this campaign were: (1) To determine the characteristics of tides in the troposphere and lower stratosphere (0–20 km) and mesosphere and lower thermosphere (MLT) region (80–100 km), (2) to explore and identify what lower atmospheric processes drive middle atmospheric tides in the Indian continental region and (3) to provide information on those short-term variabilities of MLT tides that are likely to have an impact on the ionospheric variabilities and contribute to the upper atmospheric weather. Data sets from experiments conducted at the three low latitude radar sites, namely, Trivandrum (8.5° N, 76.9° E), Tirunelveli (8.7° N, 77.8° E) and Gadanki (13.5° N, 79.2° E) and fortnightly rocket launches from Thumba were made use of in this study. An important observational finding reported in this work is that the radar observations at Tirunelveli/Trivandrum indicate the presence of 15–20 day modulation of diurnal tide activity at MLT heights during the February–March period. A similar variation in the OLR fields in the western Pacific (120–160° longitude region) suggests a possible link between the observed tidal variabilities and the variations in the deep tropical convection through the nonmigrating tides it generates.

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19

Cabral, Ivone Ketura Silva, Wilsandrei Cella y Silvia Regina Sampaio Freitas. "Reproductive behavior of women from a rural community in Tefé, Amazonas, Brazil". Brazilian Journal of Biological Sciences 6, n.º 14 (2019): 497–504. http://dx.doi.org/10.21472/bjbs.061402.

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The objective of this descriptive and retrospective study was to delineate the reproductive profile of women living in a rural community of Tefé Municipality, Amazonas State, Brazil. The target audience included women (n = 10), aged 18 years and older, living in the Agrovila community, rural area, distant 13.2 km from the center of Tefé. All participants were interviewed, individually, based on a questionnaire designed exclusively for the present study. The results of the descriptive analyzes indicated that the interviewees reached the menarche between 13 and 17 years old, and the first pregnancy occurred during adolescence, between 14 and 16 years old. Half of the women interviewed reported regular use of contraceptive methods regularly. However, the average number of children per woman was 4.6 children. All women reported prenatal care in all pregnancies. However, 50% reported complications during pregnancy; while 20% had one or two miscarriages due to eclampsia. These data point to the need to improve prenatal consultations, raise awareness about the risks of eclampsia for maternal health, as well as the creation of reproductive health programs that recognize the social and cultural conditions of isolated Amazonian communities.

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20

Sakazaki, T., M. Shiotani, M. Suzuki, D. Kinnison, J. M. Zawodny, M. McHugh y K. A. Walker. "Sunset–sunrise difference in solar occultation ozone measurements (SAGE II, HALOE, and ACE–FTS) and its relationship to tidal vertical winds". Atmospheric Chemistry and Physics Discussions 14, n.º 11 (18 de junio de 2014): 16043–83. http://dx.doi.org/10.5194/acpd-14-16043-2014.

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Abstract. This paper contains a comprehensive investigation of the sunset–sunrise difference (SSD; i.e., the sunset-minus-sunrise value) of the ozone mixing ratio in the latitude range of 10° S–10° N. SSD values were determined from solar occultation measurements based on data obtained from the Stratospheric Aerosol and Gas Experiment (SAGE) II, the Halogen Occultation Experiment (HALOE), and the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS). The SSD was negative at altitudes of 20–30 km (–0.1 ppmv at 25 km) and positive at 30–50 km (+0.2 ppmv at 40–45 km) for HALOE and ACE–FTS data. SAGE II data also showed a qualitatively similar result, although the SSD in the upper stratosphere was two times larger than those derived from the other datasets. On the basis of an analysis of data from the Superconducting Submillimeter Limb Emission Sounder (SMILES), and a nudged chemical-transport model (the Specified Dynamics version of the Whole Atmosphere Community Climate Model: SD–WACCM), we conclude that the SSD can be explained by diurnal variations in the ozone concentration, particularly those caused by vertical transport by the atmospheric tidal winds. All datasets showed significant seasonal variations in the SSD; the SSD in the upper stratosphere is greatest from December through February, while that in the lower stratosphere reaches a maximum twice: during the periods March–April and September–October. Based on an analysis of SD–WACCM results, we found that these seasonal variations follow those associated with the tidal vertical winds.

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21

Sakazaki, T., M. Shiotani, M. Suzuki, D. Kinnison, J. M. Zawodny, M. McHugh y K. A. Walker. "Sunset–sunrise difference in solar occultation ozone measurements (SAGE II, HALOE, and ACE–FTS) and its relationship to tidal vertical winds". Atmospheric Chemistry and Physics 15, n.º 2 (23 de enero de 2015): 829–43. http://dx.doi.org/10.5194/acp-15-829-2015.

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Abstract. This paper contains a comprehensive investigation of the sunset–sunrise difference (SSD, i.e., the sunset-minus-sunrise value) of the ozone mixing ratio in the latitude range of 10° S–10° N. SSD values were determined from solar occultation measurements based on data obtained from the Stratospheric Aerosol and Gas Experiment (SAGE) II, the Halogen Occultation Experiment (HALOE), and the Atmospheric Chemistry Experiment–Fourier transform spectrometer (ACE–FTS). The SSD was negative at altitudes of 20–30 km (−0.1 ppmv at 25 km) and positive at 30–50 km (+0.2 ppmv at 40–45 km) for HALOE and ACE–FTS data. SAGE II data also showed a qualitatively similar result, although the SSD in the upper stratosphere was 2 times larger than those derived from the other data sets. On the basis of an analysis of data from the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) and a nudged chemical transport model (the specified dynamics version of the Whole Atmosphere Community Climate Model: SD–WACCM), we conclude that the SSD can be explained by diurnal variations in the ozone concentration, particularly those caused by vertical transport by the atmospheric tidal winds. All data sets showed significant seasonal variations in the SSD; the SSD in the upper stratosphere is greatest from December through February, while that in the lower stratosphere reaches a maximum twice: during the periods March–April and September–October. Based on an analysis of SD–WACCM results, we found that these seasonal variations follow those associated with the tidal vertical winds.

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22

Jones, Darryl N. y Paul G. Finn. "Translocation of aggressive Australian magpies: a preliminary assessment of a potential management action". Wildlife Research 26, n.º 3 (1999): 271. http://dx.doi.org/10.1071/wr98062.

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Australian magpies are the cause of a major wildlife-management conflict in suburban areas throughout Australia. Mitigation of this conflict is becoming increasingly difficult in some locations because of community opposition to the destruction of the birds involved, which remains a common management solution of many wildlife agencies. Translocation – the capture and release elsewhere – of offending birds has been advocated but never seriously evaluated. This study aimed to assess the effectiveness of translocation as a means of eliminating magpie attacks. We also attempted to assess the impact of the approach on both the translocated birds and those remaining in the territory. A total of 20 aggressive magpies, all males, were captured and released at distances 17–150 km from the place of capture. Most birds released more than 30 km away were not seen again; two birds released less than 30 km away returned quickly and were recaptured. A single bird re-established itself on its original territory several months after capture. In many cases, new males had replaced the captured birds within days. There was no evidence of negative behavioural interactions between these males and the resident females or chicks. While the technique is effective in reducing the human–magpie conflict at specific locations, our lack of knowledge of the fate of translocated males, as well as several other issues, suggests that this approach be used only in extreme circumstances.

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23

Strzelecki, Mateusz C. y Marek W. Jaskólski. "Arctic tsunamis threaten coastal landscapes and communities – survey of Karrat Isfjord 2017 tsunami effects in Nuugaatsiaq, western Greenland". Natural Hazards and Earth System Sciences 20, n.º 9 (24 de septiembre de 2020): 2521–34. http://dx.doi.org/10.5194/nhess-20-2521-2020.

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Abstract. On the 17 June 2017, a massive landslide which mobilized 35–58 million m3 of material entered the Karrat Isfjord in western Greenland. It triggered a tsunami wave with a runup height exceeding 90 m close to the landslide, ca. 50 m on the opposite shore of the fjord. The tsunami travelled ca. 32 km along the fjord and reached the settlement of Nuugaatsiaq with ca. 1–1.5 m high waves which flooded the terrain up to 9 m a.s.l. (above sea level). Tsunami waves were powerful enough to destroy the community infrastructure, impact fragile coastal tundra landscape, and unfortunately injure several inhabitants and cause four deaths. Our field survey carried out 25 months after the event results in documentation of the previously unreported scale of damage in the settlement (ca. 48 % of infrastructure objects including houses and administration buildings were destroyed by the tsunami). We have observed a recognizable difference in the concentration of tsunami deposit accumulations between areas of the settlement overwashed by the wave and areas of runup and return flow. The key tsunami effects preserved in the coastal landscape were eroded coastal bluffs, gullied and dissected edges of cliffed coast in the harbour, and tundra vegetation compressed by boulders or icebergs rafted onshore during the event.

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24

Tripp, Daniel D., Elinor R. Martin y Heather D. Reeves. "Applications of Uncrewed Aerial Vehicles (UAVs) in Winter Precipitation-Type Forecasts". Journal of Applied Meteorology and Climatology 60, n.º 3 (marzo de 2021): 361–75. http://dx.doi.org/10.1175/jamc-d-20-0047.1.

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AbstractTemperature and humidity profiles in the lowest 3 km of the atmosphere provide crucial information in determining the precipitation type, which aids forecasters in relaying winter-weather risks. In response to the challenges associated with forecasting mixed-phase environments, this study employs uncrewed aerial vehicles (UAVs) to explore the efficacy of high-resolution temporal and vertical measurements in winter-weather environments. On 19 February 2019, boundary layer measurements of an Oklahoma winter storm were collected by a UAV and radiosondes. UAV observations show a pronounced surface-based subfreezing layer that corresponds to observed ice pellets at the surface. This is in contrast to the High-Resolution Rapid Refresh (HRRR) model analyses, which show a subfreezing layer near the surface that is 3°C warmer than both the UAV and radiosonde observations. Using a spectral-bin-microphysics algorithm designed to provide hydrometeor-phase diagnosis throughout the vertical column, it was found that UAV measurements can improve discrimination between hydrometer types in environments near 0°C. A numerical-modeling study of the same winter-weather event illustrates the potential benefit of vertically sampling a mixed-phase environment at multiple mesonet sites and highlights future scientific and operational questions to be addressed by the UAV community.

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25

Kiefer, Michael, Thomas von Clarmann, Bernd Funke, Maya García-Comas, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann et al. "IMK/IAA MIPAS temperature retrieval version 8: nominal measurements". Atmospheric Measurement Techniques 14, n.º 6 (7 de junio de 2021): 4111–38. http://dx.doi.org/10.5194/amt-14-4111-2021.

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Abstract. A new global set of atmospheric temperature profiles is retrieved from recalibrated radiance spectra recorded with the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS). Changes with respect to previous data versions include a new radiometric calibration considering the time dependency of the detector nonlinearity and a more robust frequency calibration scheme. Temperature is retrieved using a smoothing constraint, while tangent altitude pointing information is constrained using optimal estimation. ECMWF ERA-Interim is used as a priori temperature below 43 km. Above, a priori data are based on data from the Whole Atmosphere Community Climate Model Version 4 (WACCM4). Bias-corrected fields from specified dynamics runs, sampled at the MIPAS times and locations, are used, blended with ERA-Interim between 43 and 53 km. Horizontal variability of temperature is considered by scaling an a priori 3D temperature field in the orbit plane in a way that the horizontal structure is provided by the a priori while the vertical structure comes from the measurements. Additional microwindows with better sensitivity at higher altitudes are used. The background continuum is jointly fitted with the target parameters up to 58 km altitude. The radiance offset correction is strongly regularized towards an empirically determined vertical offset profile. In order to avoid the propagation of uncertainties of O3 and H2O a priori assumptions, the abundances of these species are retrieved jointly with temperature. The retrieval is based on HITRAN 2016 spectroscopic data, with a few amendments. Temperature-adjusted climatologies of vibrational populations of CO2 states emitting in the 15 µm region are used in the radiative transfer modeling in order to account for non-local thermodynamic equilibrium. Numerical integration in the radiative transfer model is now performed at higher accuracy. The random component of the temperature uncertainty typically varies between 0.4 and 1 K, with occasional excursions up to 1.3 K above 60 km altitude. The leading sources of the random component of the temperature error are measurement noise, gain calibration uncertainty, spectral shift, and uncertain CO2 mixing ratios. The systematic error is caused by uncertainties in spectroscopic data and line shape uncertainties. It ranges from 0.2 K at 20 km altitude for northern midlatitude summer conditions to 2.3 K at 12 km for tropical conditions. The estimated total uncertainty amounts to values between 0.6 K at 20 km for midlatitude summer conditions to 2.5 K at 12–15 km for tropical conditions. The vertical resolution varies around 3 km for altitudes below 50 km. The long-term drift encountered in the previous temperature product has been largely reduced. The consistency between high spectral resolution results from 2002 to 2004 and the reduced spectral resolution results from 2005 to 2012 has been largely improved. As expected, most pronounced temperature differences between version 8 and previous data versions are found in elevated stratopause situations. The fact that the phase of temperature waves seen by MIPAS is not locked to the wave phase found in ECMWF analyses demonstrates that our retrieval provides independent information and does not merely reproduce the prior information.

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26

Han, Xiao, Lingyun Zhu, Mingxu Liu, Yu Song y Meigen Zhang. "Numerical analysis of agricultural emissions impacts on PM2.5 in China using a high-resolution ammonia emission inventory". Atmospheric Chemistry and Physics 20, n.º 16 (27 de agosto de 2020): 9979–96. http://dx.doi.org/10.5194/acp-20-9979-2020.

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Abstract. China is one of the largest agricultural countries in the world. Thus, NH3 emission from agricultural activities in China considerably affects the country's regional air quality and visibility. In this study, a high-resolution agricultural NH3 emission inventory compiled on 1 km × 1 km horizontal resolution was applied to calculate the NH3 mass burden in China and reliably estimate the influence of NH3 on agriculture. The key parameter emission factors of this inventory were enhanced by considering many experiment results, and the dynamic data of spatial and temporal information were updated using statistical data of 2015. In addition to fertilizers and husbandry, farmland ecosystems, livestock waste, crop residue burning, wood-based fuel combustion, and other NH3 emission sources were included in this inventory. Furthermore, a source apportionment tool, namely, the Integrated Source Apportionment Method (ISAM) coupled with the air quality modeling system Regional Atmospheric Modeling System and Community Multiscale Air Quality, was applied to capture the contribution of NH3 emitted from total agriculture (Tagr) in China. The aerosol mass concentration in 2015 was simulated, and results showed that the high mass concentration of NH3 exceeded 10 µg m−3 and mainly appeared in the North China Plain, Central China, the Yangtze River Delta, and the Sichuan Basin. Moreover, the annual average contribution of Tagr NH3 to PM2.5 mass burden was 14 %–22 % in China. Specific to the PM2.5 components, Tagr NH3 contributed dominantly to ammonium formation (87.6 %) but trivially to sulfate formation (2.2 %). In addition, several brute-force sensitivity tests were conducted to estimate the impact of Tagr NH3 emission reduction on PM2.5 mass burden. In contrast to the result of ISAM, even though the Tagr NH3 only provided 10.1 % contribution to nitrate under the current emission scenario, the reduction of nitrate could reach 95.8 % upon removal of the Tagr NH3 emission. This deviation occurred because the contribution of NH3 to nitrate should be small under a “rich NH3”environment and large under a “poor NH3” environment. Thus, the influence of NH3 on nitrate formation would be enhanced with the decrease in ambient NH3 mass concentration.

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27

Ratno, Puji, Miftahul Ihsan y Budi Ali Mukmin. "KOMUNITAS OLAHRAGA REMAJA DESA". JURNAL PENGABDIAN KEPADA MASYARAKAT 23, n.º 4 (24 de julio de 2018): 384. http://dx.doi.org/10.24114/jpkm.v23i4.10338.

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AbstrakTujuan dari kegiatan pengabdian masyarakat ini adalah untuk melaksanakan salah satu tridharma perguruan tinggi, khususnya bidang pengabdian kepada masyarakat untuk membantu mitra dalam menyelesaikan permasalahan yang dihadapinya, mulai dari aspek kesertaaan remaja dalam latihan pencak silat, program latihan, dan perlengkapan latihan. Target khusus dalam kegiatan ini dihasilkannnya perlengkapan latihan pencak silat yang standard nasional dalam pertandingan.metode yang digunakan untuk mencapai kegiatan ini adalah metode FGD, Penyuluhan dan sosialisasi bahaya penggunaan narkoba,Pembentukan komunitas olaharaga remaja desa,Pendampingan latihan olahraga bagi komunitas olahraga remaja desa Mitra dalam kegiatan pengabdian ini adalah perguaran silat garuda sakti dan Asslam. Jarak kedua mitra ± 20 km dari Universitas Negeri Medan dan dapat ditempuh dengan angkutan umum selama 30 menit. Komunitas pencak silat merupakan satu komunitas yang telah berdiri sejak tahun 2010 yang berada di desa Suka Makmur Kabupaten Deli Serdang. Akan tetapi dalam menjalankan program latihannya masih banyak mengalami kendala. Kesertaaan remaja dalam mengikuti latihan yang masih sedikit, metode melatih yang masih konvensional,pelatih tidak memiliki program latihan yang tertulis dan peralatan latihan yang belum memadai.Oleh karena itu diperlukan upaya yang konstruktif yang dapat mengatasi mengatasi permasalahan tersebut dengan kegiatan pelatuhan dan pendampingan. Kegiatan yang telah dilakukan adalah penyuluhan tentang bahaya narkoba bagi remaja, coching clinic bagi pelatih, pendampingan latihan karate, dan penyediaan peralatan latihan pencak silat.Kata Kunci : Komunitas, Olahraga, Remaja.AbstractThe purpose of this community service activity is to implement one of the Tri Dharma colleges, especially the field of community service to help partners in solving the problems they face, ranging from the aspect of teenagers in the practice of martial arts, exercise programs, and exercise equipment. Specific targets in this activity resulted in national standard pencak silat training equipment in the matches. Methods used to achieve this activity were FGD methods, extension and socialization of the hazards of drug use, Establishment of youth village teens, Assistance of sports exercises for youth community of village village Partners in this devotional activity is a silat garuda silat and Asslam silat. Distance of two partners ± 20 km from the State University of Medan and can be reached by public transport for 30 minutes. Pencak Silat community is a community that has been established since 2010 located in the village of Suka Makmur Deli Serdang Regency. However, in running the training program is still experiencing many obstacles. Teenagers' participation in training, conventional training methods, trainers do not have a written exercise program and inadequate training equipment. Therefore, constructive efforts are needed to overcome these problems with the accompaniment of accompaniment and accompaniment. Activities that have been done are counseling about the dangers of drugs for teenagers, coching clinic for trainers, karate training accompaniment, and the provision of training equipment pencak silat.Keywords: Community, Sports, Youth

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28

Guo, Y., P. J. Somerfield, R. M. Warwick y Z. Zhang. "Large-scale patterns in the community structure and biodiversity of freeliving nematodes in the Bohai Sea, China". Journal of the Marine Biological Association of the United Kingdom 81, n.º 5 (octubre de 2001): 755–63. http://dx.doi.org/10.1017/s0025315401004568.

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Freeliving marine nematodes were sampled on two occasions from an extensive grid of 20 stations in the Bohai Sea and its approaches. Differences within stations between sampling periods were small, resulting from small changes in abundance of dominant species. Differences between stations were significant, and were used to cluster stations into groups with similar species composition. These station groupings revealed a weak faunal gradient leading from the mouth of the Huanghe (Yellow River) to the Bohai Strait. Analyses relating faunal composition to environmental variables showed that there were significant differences in environmental variables between faunally-defined groups of stations. The variables most closely correlated with community structure were silt/clay and sand, depth, phaeopigment concentrations below the sediment surface, organic content and arsenic. These reflect natural processes within the Bohai Sea. A suite of univariate measures were related to distance from the river mouth, with a major discontinuity about 120 km into the Bohai Sea. Comparison of values of the biodiversity measures average taxonomic distinctness (Δ+) and variation in taxonomic distinctness (Λ+) suggest that the meiobenthos of the Bohai Sea as a whole is not under major pollution stress.

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29

Goldberg, Daniel L., Lok N. Lamsal, Christopher P. Loughner, William H. Swartz, Zifeng Lu y David G. Streets. "A high-resolution and observationally constrained OMI NO2 satellite retrieval". Atmospheric Chemistry and Physics 17, n.º 18 (26 de septiembre de 2017): 11403–21. http://dx.doi.org/10.5194/acp-17-11403-2017.

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Abstract. This work presents a new high-resolution NO2 dataset derived from the NASA Ozone Monitoring Instrument (OMI) NO2 version 3.0 retrieval that can be used to estimate surface-level concentrations. The standard NASA product uses NO2 vertical profile shape factors from a 1.25° × 1° (∼ 110 km × 110 km) resolution Global Model Initiative (GMI) model simulation to calculate air mass factors, a critical value used to determine observed tropospheric NO2 vertical columns. To better estimate vertical profile shape factors, we use a high-resolution (1.33 km × 1.33 km) Community Multi-scale Air Quality (CMAQ) model simulation constrained by in situ aircraft observations to recalculate tropospheric air mass factors and tropospheric NO2 vertical columns during summertime in the eastern US. In this new product, OMI NO2 tropospheric columns increase by up to 160 % in city centers and decrease by 20–50 % in the rural areas outside of urban areas when compared to the operational NASA product. Our new product shows much better agreement with the Pandora NO2 and Airborne Compact Atmospheric Mapper (ACAM) NO2 spectrometer measurements acquired during the DISCOVER-AQ Maryland field campaign. Furthermore, the correlation between our satellite product and EPA NO2 monitors in urban areas has improved dramatically: r2 = 0.60 in the new product vs. r2 = 0.39 in the operational product, signifying that this new product is a better indicator of surface concentrations than the operational product. Our work emphasizes the need to use both high-resolution and high-fidelity models in order to recalculate satellite data in areas with large spatial heterogeneities in NOx emissions. Although the current work is focused on the eastern US, the methodology developed in this work can be applied to other world regions to produce high-quality region-specific NO2 satellite retrievals.

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30

Basu, Ben K., J. Kalff y B. Pinel-Alloul. "Midsummer plankton development along a large temperate river: the St. Lawrence River". Canadian Journal of Fisheries and Aquatic Sciences 57, S1 (14 de marzo de 2000): 7–15. http://dx.doi.org/10.1139/f99-249.

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Midsummer planktonic communities were sampled in 1997 along a 425-km reach of the St. Lawrence River between Lake Ontario and Trois-Rivières (Quebec) to describe longitudinal patterns of plankton development. Chlorophyll a (Chl a) quickly declined as water flowed from Lake Ontario into the river. Thereafter, in the reach upstream from Montreal, Chl a was ~1 µg·L-1 and total phosphorus (TP) was ~10 µg·L-1. Downstream from Montreal, TP increased to 20-40 µg·L-1 and Chl a rose to 2-5 µg·L-1. Although Chl a increased concomitant with TP, phytoplankton may have been light limited at the more turbid downstream stations. Zooplankton biomass decreased from 40 µg dry mass·L-1 in Lake Ontario to 16 µg dry mass·L-1 at Brockville, 90 km downstream. Zooplankton biomass continued to decline and downstream from Montreal remained <10 µg dry mass·L-1, despite the increased TP and Chl a. Rotifers dominated the zooplankton community, but as in other temperate rivers, total zooplankton biomass was low (<10 µg dry mass·L-1). There was no longitudinal pattern in heterotrophic bacterial or flagellate abundance. A comparison of the inflow and outflow biomass of two fluvial lakes showed the lakes to contribute little to the downstream river plankton during summer.

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31

Coleman, Noël, Wilfred Cuff, John Moverley, Anne S. H. Gason y Simon Heislers. "Depth, sediment type, biogeography and high species richness in shallow-water benthos". Marine and Freshwater Research 58, n.º 3 (2007): 293. http://dx.doi.org/10.1071/mf06098.

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Until recently, quantitative data on the benthic fauna along the coast of Victoria, south-east Australia, were restricted to those few areas (potentially) receiving commercial and industrial effluent. Collectively, studies in these areas covered ~50 to 60 km of a coastline that extends for 1000 km. Recently, samples were taken from depths of 10, 20 and 40 m along the entire coast, and analysis of these made it possible to examine benthic community structure throughout the region. Species richness is high along the entire length of the coast, supporting the argument that species richness in temperate areas is not always higher in the deep sea than in shallow water. The major factor influencing species richness was depth. Although slightly more individuals were collected from stations at 10-m depth than from stations at 40-m depth, almost three times as many species were found at the deeper stations. Sediment type also influenced species richness. For the stations at 40-m depth, species richness was ~25% higher in medium and coarse sands than in fine sand. Pattern analysis suggested some bioregionalisation of the fauna, but the effect of geographical location on affinities among sample stations was much less than the effects of depth and sediment type.

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32

Stuart, Ivor G., Brenton P. Zampatti y Lee J. Baumgartner. "Can a low-gradient vertical-slot fishway provide passage for a lowland river fish community?" Marine and Freshwater Research 59, n.º 4 (2008): 332. http://dx.doi.org/10.1071/mf07141.

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Fishways are commonly used to restore native fish movements in regulated rivers. In the Murray-Darling Basin, Australia, 14 fishways are to be built by 2011 to improve passage along 2225 km of the river. The first of these fishways, constructed in 2003, is a vertical-slot design with low water velocities (0.98–1.4 m s–1) and turbulence (average 42 W m–3). This design was selected to provide passage for individuals between 20 and 1000 mm long. To determine passage success, trapping and a remote automated passive integrated transponder (PIT) tag reading system was used from October 2003 to February 2006. In 57 24-h samples at the exit (upstream end) and entrance (downstream end), 13 species and 30 409 fish were collected at a maximum rate of 4415 fish per day. Fish between 31 and 1030 mm successfully ascended the fishway. However, significantly smaller (<31 mm) fish and small-bodied (<50 mm) carp gudgeons (Hypseleotris spp.), a species previously considered non-migratory, were sampled downstream from the entrance of the fishway. The remote PIT tag reading system revealed that 81% of native golden perch (Macquaria ambigua) and 87% of non-native common carp (Cyprinus carpio) successfully ascended the fishway. These data will help maximise the efficiency of future fishways against a series of pre-determined performance criteria.

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33

Poiner, IR, DJ Staples y R. Kenyon. "Seagrass communities of the Gulf of Carpentaria, Australia". Marine and Freshwater Research 38, n.º 1 (1987): 121. http://dx.doi.org/10.1071/mf9870121.

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The seagrass communities of the Gulf of Carpentaria were mapped and classified in terms of their species composition, their areas of shoot surface and their above-ground biomass. A total of 906.4 km2 of seagrass habitat, fringing 671.1 km of coastline was identified, mapped and sampled. Eleven seagrass species (approx. 20% of all known species) were recorded. In all, 74% of the seagrass communities occur along open coastlines and are characterized by depth-zoned species distributions (intertidally and subtidally), variable shoot-surface areas and variable above-ground biomass values. Each zone was dominated bfone or two of the following species: Syringodium isoetifolium, Cymodocea serrulata, Halodule uninervis, Halophila ovalis and Halophila spinulosa. Of the remaining seagrass, 10% occurred on reef flats in mixed-species communities, !3% in a regionally restricted monospecific community of Halodule uninervis, and 4% in communities dominated by Enhalus acoroides.

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34

Rossi, Lucio y Carmine Senatore. "HTS Accelerator Magnet and Conductor Development in Europe". Instruments 5, n.º 1 (23 de febrero de 2021): 8. http://dx.doi.org/10.3390/instruments5010008.

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In view of the preparation for a post-LHC collider, in 2010 the high-energy physics (HEP) community started to discuss various options, including the use of HTS for very high-field dipoles. Therefore, a small program was begun in Europe that aimed at exploring the possibility of using HTS for accelerator-quality magnets. Based on various EU-funded programs, though at modest levels, it has enabled the European community of accelerator magnet research to start getting experience in HTS and address a few issues. The program was based on the use of REBa2Cu3O7−x (REBCO) tapes to form 10 kA Roebel cables to wind small dipoles of 30–40 mm aperture in the 5 T range. The dipoles are designed to be later inserted in a background dipole field (in Nb3Sn), to reach eventually a field level in the 16–20 T range, beyond the reach of Low Temperature Superconductors (LTS). The program is currently underway: more than 1 km of high-performance tape (Je > 500 A/mm2 at 20 T, 4.2 K) has been manufactured and characterized, various 30 m long Roebel cables have been assembled and validated up to 13 kA, a few dipoles have been wound and tested, reaching 4.5 T in stand-alone (while a dipole made from flat race track coils exceeded 5 T using stacked tape cable), and tests in background field are being organized.

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Hewage, Pradeep, Ardhendu Behera, Marcello Trovati, Ella Pereira, Morteza Ghahremani, Francesco Palmieri y Yonghuai Liu. "Temporal convolutional neural (TCN) network for an effective weather forecasting using time-series data from the local weather station". Soft Computing 24, n.º 21 (23 de abril de 2020): 16453–82. http://dx.doi.org/10.1007/s00500-020-04954-0.

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Abstract Non-predictive or inaccurate weather forecasting can severely impact the community of users such as farmers. Numerical weather prediction models run in major weather forecasting centers with several supercomputers to solve simultaneous complex nonlinear mathematical equations. Such models provide the medium-range weather forecasts, i.e., every 6 h up to 18 h with grid length of 10–20 km. However, farmers often depend on more detailed short-to medium-range forecasts with higher-resolution regional forecasting models. Therefore, this research aims to address this by developing and evaluating a lightweight and novel weather forecasting system, which consists of one or more local weather stations and state-of-the-art machine learning techniques for weather forecasting using time-series data from these weather stations. To this end, the system explores the state-of-the-art temporal convolutional network (TCN) and long short-term memory (LSTM) networks. Our experimental results show that the proposed model using TCN produces better forecasting compared to the LSTM and other classic machine learning approaches. The proposed model can be used as an efficient localized weather forecasting tool for the community of users, and it could be run on a stand-alone personal computer.

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Baum, Gunilla, Indra Januar, Sebastian C. A. Ferse, Christian Wild y Andreas Kunzmann. "Abundance and physiology of dominant soft corals linked to water quality in Jakarta Bay, Indonesia". PeerJ 4 (29 de noviembre de 2016): e2625. http://dx.doi.org/10.7717/peerj.2625.

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Declining water quality is one of the main reasons of coral reef degradation in the Thousand Islands off the megacity Jakarta, Indonesia. Shifts in benthic community composition to higher soft coral abundances have been reported for many degraded reefs throughout the Indo-Pacific. However, it is not clear to what extent soft coral abundance and physiology are influenced by water quality. In this study, live benthic cover and water quality (i.e. dissolved inorganic nutrients (DIN), turbidity (NTU), and sedimentation) were assessed at three sites (< 20 km north of Jakarta) in Jakarta Bay (JB) and five sites along the outer Thousand Islands (20–60 km north of Jakarta). This was supplemented by measurements of photosynthetic yield and, for the first time, respiratory electron transport system (ETS) activity of two dominant soft coral genera,Sarcophytonspp. andNephtheaspp. Findings revealed highly eutrophic water conditions in JB compared to the outer Thousand Islands, with 44% higher DIN load (7.65 μM/L), 67% higher NTU (1.49 NTU) and 47% higher sedimentation rate (30.4 g m−2d−1). Soft corals were the dominant type of coral cover within the bay (2.4% hard and 12.8% soft coral cover) compared to the outer Thousand Islands (28.3% hard and 6.9% soft coral cover). Soft coral abundances, photosynthetic yield, and ETS activity were highly correlated with key water quality parameters, particularly DIN and sedimentation rates. The findings suggest water quality controls the relative abundance and physiology of dominant soft corals in JB and may thus contribute to phase shifts from hard to soft coral dominance, highlighting the need to better manage water quality in order to prevent or reverse phase shifts.

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Cheviron, Bruno y Roger Moussa. "Determinants of modelling choices for 1-D free-surface flow and morphodynamics in hydrology and hydraulics: a review". Hydrology and Earth System Sciences 20, n.º 9 (14 de septiembre de 2016): 3799–830. http://dx.doi.org/10.5194/hess-20-3799-2016.

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Abstract. This review paper investigates the determinants of modelling choices, for numerous applications of 1-D free-surface flow and morphodynamic equations in hydrology and hydraulics, across multiple spatiotemporal scales. We aim to characterize each case study by its signature composed of model refinement (Navier–Stokes: NS; Reynolds-averaged Navier–Stokes: RANS; Saint-Venant: SV; or approximations to Saint-Venant: ASV), spatiotemporal scales and subscales (domain length: L from 1 cm to 1000 km; temporal scale: T from 1 s to 1 year; flow depth: H from 1 mm to 10 m; spatial step for modelling: δL; temporal step: δT), flow typology (Overland: O; High gradient: Hg; Bedforms: B; Fluvial: F), and dimensionless numbers (dimensionless time period T*, Reynolds number Re, Froude number Fr, slope S, inundation ratio Λz, Shields number θ). The determinants of modelling choices are therefore sought in the interplay between flow characteristics and cross-scale and scale-independent views. The influence of spatiotemporal scales on modelling choices is first quantified through the expected correlation between increasing scales and decreasing model refinements (though modelling objectives also show through the chosen spatial and temporal subscales). Then flow typology appears a secondary but important determinant in the choice of model refinement. This finding is confirmed by the discriminating values of several dimensionless numbers, which prove preferential associations between model refinements and flow typologies. This review is intended to help modellers in positioning their choices with respect to the most frequent practices, within a generic, normative procedure possibly enriched by the community for a larger, comprehensive and updated image of modelling strategies.

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Villalobos, Yohanna, Peter Rayner, Steven Thomas y Jeremy Silver. "The potential of Orbiting Carbon Observatory-2 data to reduce the uncertainties in CO2 surface fluxes over Australia using a variational assimilation scheme". Atmospheric Chemistry and Physics 20, n.º 14 (21 de julio de 2020): 8473–500. http://dx.doi.org/10.5194/acp-20-8473-2020.

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Abstract. This paper addresses the question of how much uncertainties in CO2 fluxes over Australia can be reduced by assimilation of total-column carbon dioxide retrievals from the Orbiting Carbon Observatory-2 (OCO-2) satellite instrument. We apply a four-dimensional variational data assimilation system, based around the Community Multiscale Air Quality (CMAQ) transport-dispersion model. We ran a series of observing system simulation experiments to estimate posterior error statistics of optimized monthly-mean CO2 fluxes in Australia. Our assimilations were run with a horizontal grid resolution of 81 km using OCO-2 data for 2015. Based on four representative months, we find that the integrated flux uncertainty for Australia is reduced from 0.52 to 0.13 Pg C yr−1. Uncertainty reductions of up to 90 % were found at grid-point resolution over productive ecosystems. Our sensitivity experiments show that the choice of the correlation structure in the prior error covariance plays a large role in distributing information from the observations. We also found that biases in the observations would significantly impact the inverted fluxes and could contaminate the final results of the inversion. Biases in prior fluxes are generally removed by the inversion system. Biases in the boundary conditions have a significant impact on retrieved fluxes, but this can be mitigated by including boundary conditions in our retrieved parameters. In general, results from our idealized experiments suggest that flux inversions at this unusually fine scale will yield useful information on the carbon cycle at continental and finer scales.

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Lader, Rick, Allison Bidlack, John E. Walsh, Uma S. Bhatt y Peter A. Bieniek. "Dynamical Downscaling for Southeast Alaska: Historical Climate and Future Projections". Journal of Applied Meteorology and Climatology 59, n.º 10 (1 de octubre de 2020): 1607–23. http://dx.doi.org/10.1175/jamc-d-20-0076.1.

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AbstractWarming temperatures across southeast Alaska are affecting the region’s energy and transportation sectors, marine ecosystems, and forest health. More frequent above-freezing temperatures lead a transition from snow- to rain-dominant precipitation regimes, accelerating glacial mass balance loss and a leading to a greater risk for warm-season drought. Southeast Alaska has steep topographical gradients, which necessitate the use of downscaled climate information to study historical and projected periods. This study used regional dynamical downscaling at 4-km spatial resolution with the Weather Research and Forecasting Model to assess historical (1981–2010) and projected (2031–60) climate states for southeast Alaska. These simulations were driven by one reanalysis (i.e., the Climate Forecast System Reanalysis) and two climate models (i.e., the Geophysical Fluid Dynamics Laboratory Climate Model, version 3, and the NCAR Community Climate System Model, version 4), which each included a historical simulation and a projected simulation. The future simulations used the representative concentration pathway 8.5 emissions scenario. Bias-corrected projections (2031–60 minus 1981–2010) indicated seasonal warming of 1°–3°C, increased precipitation during autumn (4%–12%) and winter (7%–12%), and decreased snowfall in all seasons (up to 60% in autumn). The average number of days annually with a minimum temperature below freezing dropped by more than 30. The average annual maximum consecutive 3-day precipitation amounts increased by 11%–16%, but analogous extreme snowfall amounts dropped by 5%–11%. The most substantial snow losses occurred at low-elevation and coastal locations; at many high elevations (e.g., above 1000 m), extreme snowfall amounts increased.

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Kuupiel, Desmond, Kwame M. Adu, Vitalis Bawontuo, Duncan A. Adogboba y Tivani P. Mashamba-Thompson. "Estimating the Spatial Accessibility to Blood Group and Rhesus Type Point-of-Care Testing for Maternal Healthcare in Ghana". Diagnostics 9, n.º 4 (5 de noviembre de 2019): 175. http://dx.doi.org/10.3390/diagnostics9040175.

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Background: In Ghana, a blood group and rhesus type test is one of the essential recommended screening tests for women during antenatal care since blood transfusion is a key intervention for haemorrhage. We estimated the spatial accessibility to health facilities for blood group and type point-of-care (POC) testing in the Upper East Region (UER), Ghana. Methods: We assembled the attributes and spatial data of hospitals, clinics, and medical laboratories providing blood group and rhesus type POC testing in the UER. We also obtained the spatial data of all the 131 towns, and 94 health centres and community-based health planning and services (CHPS) compounds providing maternal healthcare in the region. We further obtained the topographical data of the region, and travel time estimated using an assumed tricycle speed of 20 km/h. We employed ArcGIS 10.5 to estimate the distance and travel time and locations with poor spatial access identified for priority improvement. Findings: In all, blood group and rhesus type POC testing was available in 18 health facilities comprising eight public hospitals and six health centres, one private hospital, and three medical laboratories used as referral points by neighbouring health centres and CHPS compounds without the service. Of the 94 health centres and CHPS compounds, 51.1% (48/94) and 66.4% (87/131) of the towns were within a 10 km range to a facility providing blood group and rhesus type testing service. The estimated mean distance to a health facility for blood group and rhesus POC testing was 8.9 ± 4.1 km, whilst the mean travel time was 17.8 ± 8.3 min. Builsa South district recorded the longest mean distance (25.6 ± 7.4 km), whilst Bongo district recorded the shortest (3.1 ± 1.9 km). The spatial autocorrelation results showed the health facilities providing blood group and rhesus type POC testing were randomly distributed in the region (Moran Index = 0.29; z-score = 1.37; p = 0.17). Conclusion: This study enabled the identification of district variations in spatial accessibility to blood group and rhesus type POC testing in the region for policy decisions. We urge the health authorities in Ghana to evaluate and implement recommended POC tests such as slide agglutination tests for blood group and rhesus type testing in resource-limited settings.

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Chen, Zhong, Pawan K. Bhartia, Omar Torres, Glen Jaross, Robert Loughman, Matthew DeLand, Peter Colarco, Robert Damadeo y Ghassan Taha. "Evaluation of the OMPS/LP stratospheric aerosol extinction product using SAGE III/ISS observations". Atmospheric Measurement Techniques 13, n.º 6 (30 de junio de 2020): 3471–85. http://dx.doi.org/10.5194/amt-13-3471-2020.

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Abstract. The Ozone Mapping and Profiler Suite Limb Profiler (OMPS/LP) has been taking limb-scattered measurements since April 2012. It is designed to produce ozone and aerosol vertical profiles at a 1.6 km vertical resolution over the entire sunlit globe. The Version 1.5 (V1.5) aerosol extinction retrieval algorithm provides aerosol extinction profiles using observed radiances at 675 nm. The algorithm assumes Mie theory and a gamma function aerosol size distribution for the stratospheric aerosol that is derived from results calculated by the Community Aerosol and Radiation Model for Atmospheres (CARMA). In this paper, we compare V1.5 LP aerosol profiles with SAGE III/ISS solar occultation observations for the period from June 2017 to May 2019, when both measurements were available to evaluate our ability to characterize background aerosol conditions. Overall, LP extinction profiles agree with SAGE III/ISS data to within ±25 % for altitudes between 19 and 27 km, even during periods perturbed by volcanic eruptions or intense forest fires. In this altitude range, the slope parameter of linear fitting of LP extinction values with respect to SAGE III/ISS measurements is close to 1.0, with Pearson correlation coefficients of r≥0.95, indicating that the LP aerosol data are reliable in that altitude range. Comparisons of extinction time series show that both instruments capture the variability of the stratospheric aerosol layer quite well, and the differences between the two instruments vary from 0 % to ±25 % depending on altitude, latitude, and time. In contrast, we find erroneous seasonal variations in the OMPS/LP Version 1.5 dataset, which usually exist below 20 km in the Southern Hemisphere due to the lack of sensitivity to particles when the scattering angle (SA) is greater than 145∘. We also find that LP-retrieved extinction is systematically higher than SAGE III/ISS observations at altitudes above 28 km and systematically lower below 19 km in the tropics with significant biases up to ±13 %. This is likely due in part to the fact that the actual aerosol size distribution is altitude dependent. There are also other reasons related to cloud contamination, wavelength limitations, aerosol loading, and the influence of the viewing configuration.

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SERRA, G., C. BRUSCHINI, L. PESKE, A. KUBSA, M. WONDAFRASH y J. A. LINDSELL. "An assessment of ecological conditions and threats at the Ethiopian wintering site of the last known eastern colony of Critically Endangered Northern Bald Ibis Geronticus eremita". Bird Conservation International 23, n.º 4 (29 de octubre de 2013): 399–413. http://dx.doi.org/10.1017/s0959270913000397.

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SummaryThe long-range, migratory eastern relict population of Northern Bald Ibis Geronticus eremita has been steadily declining since the time of discovery in 2002, despite the protection programme in place at the breeding grounds in Syria. Assessing the ecological conditions and threats along the migration route and at the wintering site, both discovered in 2006, has become a priority for this “Critically Endangered” species. Adult ibises spent the winter at the same site on the central Ethiopian highland plateau, from August until mid-February during five consecutive winters (2006-2011). The wintering site was surveyed during four field visits and assessed through a spatial analysis of 1,067 satellite locations. The site is in an agro-pastoral landscape, inhabited by a settled community of people living in relatively poor and isolated conditions. Home range analysis based on kernel distributions showed that the bald ibises used a core range area of 9.1–19.0 km² (confirmed by direct visual observations in the field) and an extended range area of 61.0–126.1 km². These figures are c.20 and 60 times smaller, respectively, than those calculated for the breeding site in Syria. Eighty-one percent of the core area in Ethiopia was used in all five years confirming the birds’ fidelity to this wintering site. Ibises preferred to forage in wet or dry pastures and in recently cut hayfields, and avoided tall grass, uncut hayfields and cultivation. Despite dependence on human-created habitats, human disturbance observed in the field was minimal. The main short-term threat for the ibises was judged to be the potential raising of attention on the part of the local community specifically towards these few individual ibises. In the medium term, the main threat comes from the conversion of pastures into crops and the potential use of fertilisers and pesticides.

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Faber, Mieke y AJS Benadé. "Nutritional status and dietary practices of 4–24-month-old children from a rural South African community". Public Health Nutrition 2, n.º 2 (febrero de 1999): 179–85. http://dx.doi.org/10.1017/s1368980099000233.

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AbstractObjectivesTo assess the nutritional status and dietary practices of 4–24-month-old children (under-twos) in a rural South African community.DesignCross-sectional survey.SettingA low socioeconomic rural African community (Ndunakazi), approximately 60 km north-west of Durban, KwaZulu-Natal, South Africa.SubjectsChildren (n= 115), 4–24 months old who attended growth monitoring posts in the area.ResultsOf these under-twos, 37.3% had low vitamin A status (serum retinol < 20 μg dl−1), 65.2% were anaemic, 43.2% had serum ferritin levels < 10 μgl−1(an indicator of low iron stores) and 15.3% were stunted. Breastfeeding was initiated by 99% of mothers. At the time of the survey, 80% of infants in the 4–12-month-old category and 56.9% of children in the 12–24-month-old category were being breastfed. Solid foods were introduced at 3.6 ± 0.8 months. Food intake reflected a high intake of carbohydrate-rich foods, and irregular intakes of fruit and vegetables, especially those rich in vitamin A. Foods of animal origin were not consumed regularly. Of these under-twos, 15.9% experienced an episode of diarrhoea during 2 weeks prior to the survey.ConclusionThese under-twos had a poor vitamin A and iron status. Nutrition education, intervention programmes and feeding schemes should address micronutrient deficiencies, with the focus on the quality of the diet, rather than quantity.

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Sopian, Nor Ashikin, Juliana Jalaludin, Suhaili Abu Bakar, Titi Rahmawati Hamedon y Mohd Talib Latif. "Exposure to Particulate PAHs on Potential Genotoxicity and Cancer Risk among School Children Living Near the Petrochemical Industry". International Journal of Environmental Research and Public Health 18, n.º 5 (4 de marzo de 2021): 2575. http://dx.doi.org/10.3390/ijerph18052575.

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This study aimed to assess the association of exposure to particle-bound (PM2.5) polycyclic aromatic hydrocarbons (PAHs) with potential genotoxicity and cancer risk among children living near the petrochemical industry and comparative populations in Malaysia. PM2.5 samples were collected using a low-volume sampler for 24 h at three primary schools located within 5 km of the industrial area and three comparative schools more than 20 km away from any industrial activity. A gas chromatography–mass spectrometer was used to determine the analysis of 16 United States Environmental Protection Agency (USEPA) priority PAHs. A total of 205 children were randomly selected to assess the DNA damage in buccal cells, employing the comet assay. Total PAHs measured in exposed and comparative schools varied, respectively, from 61.60 to 64.64 ng m−3 and from 5.93 to 35.06 ng m−3. The PAH emission in exposed schools was contributed mainly by traffic and industrial emissions, dependent on the source apportionment. The 95th percentiles of the incremental lifetime cancer risk estimated using Monte Carlo simulation revealed that the inhalation risk for the exposed children and comparative populations was 2.22 × 10−6 and 2.95 × 10−7, respectively. The degree of DNA injury was substantially more severe among the exposed children relative to the comparative community. This study reveals that higher exposure to PAHs increases the risk of genotoxic effects and cancer among children.

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Mailani, Elvi, Novita Indah Hasibuan y Yusnizar Heniwaty. "ANALISIS DESKRIPTIF PENGEMBANGAN KAWASAN EKONOMI MASYARAKAT (KEM) SIMPANG TIGA DI KOTA TANJUNG PINANG". JURNAL PENGABDIAN KEPADA MASYARAKAT 24, n.º 3 (19 de diciembre de 2018): 808. http://dx.doi.org/10.24114/jpkm.v24i3.11620.

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AbstrakKampung Madong RT 1/ RW 5 merupkan salah satu kampung yang terletak di kelurahan Kampung Bugis, kecamatan Tanjungpinang Kota, Kota Tanjungpinang, Propinsi Kepulauan Riau. Kondisi umum wilayah adalah merupakan daerah pesisir dengan jenis tanah berlumpur. Kampung dengan jumlah penduduk 448 jiwa (136 KK), dengan luas wilayah yang dihuni ± 4 Ha. Jarak tempuh dari Pusat Pemerintahan Kota Tanjungpinang dengan jarak 18 Km, dengan waktu tempuh sekitar 20 menit (menggunakan kendaraan roda empat/roda dua). Jalan akses memiliki lebar ratarata 6 meter dengan perkerasan aspal. Akses untuk mencapai lokasi cukup mudah karena umumnya masyarakat disekitar memiliki kendaraan roda dua. Masyarakat juga dapat mencapai Kota Tanjung Pinang melalui wilayah laut dengan menggunakan perahu bermesin dengan waktu tempuh sekitar 10 menit. Pelaksanaan kegiatan KEM Madong terhitung mulai tanggal 29 September 2017. Strategi yang diterapkan pada KEM ini adalah pemberian bantuan kelengkapan dan bahan baku bagi masyarakat untuk meningkatkan ekonomi masyarakat. Kelengkapan dan bahan baku ini terkait dengan kegiatan harian masyarakat dalam mencari nafkah dan meningkatkan taraf hidupnya. Diharapkan keterbatasan modal masyarakat dalam menyediakan kelengkapan dan bahan baku ini dapat diatasi dengan bantuan dari Pertamina melalui program ini. Dengan adanya program ini,jumlah penerima manfaat sebanyak 51 orang yang terbagi dalam lima kelompok kecil untuk memudahkan pelaksanaan kegiatan. Sampai dengan laporan ini disampaikan ± 8 bulan, kegiatan panen baru saja dilaksanakan. Budidaya ikan jenis kerapu cantang ini akan menuai hasilnya setelah durasi 8 bulan sejak penyebaran benih dengan rerata berat ikan sebesar 700- 800 gram/ekor.Kata kunci: Budidaya Ikan Lele, Kawasan Ekonomi Masyarakat, Kerambah Apung, Kota Tanjung PinangAbstractMadong Village is one of the villages located in the village of Bugis Village at the city of Tanjungpinang, the capital city of Riau Islands Province. The general land condition of the area is covered by coastal areas with large amount of muddy soil found in all over places in the city. The number of people in Madong village amounted of 448 people (136 families), with a total area of ± 4 hectares. It is a shortdistance in between the Tanjungpinang City Government Center and the village (18 Km), with a travel time of about 20 minutes (using a four-wheeled vehicle / two-wheeled vehicle). The access road has an average width of 6 meters with asphalt pavement. Access to reach the location is quite easy because generally the surrounding community has two-wheeled vehicles. The community can also reach the city of Tanjung Pinang through the sea by using motorized boats with a travel time of about 10 minutes. The implementation of KEM Madong activities began on September 29, 2017. The strategy adopted in this KEM was the provision of completeness and raw materials for the community to improve the economy of the community. Completeness and raw materials are related to the daily activities of the community in earning a living and improving their standard of living. It is expected that the limited capital of the community in providing these raw materials and materials can be overcome with assistance from Pertamina through this program. With this program, there were 51 beneficiaries divided into five small groups to facilitate the implementation of activities. Until this report was delivered ± 8 months, harvesting was just carried out. The harvesting of cantang grouper fish takes up to 8 months and expected to have a fish weight around 700-800 grams.Keywords: Cat Fish Harvesting, Community Economic Zone, Floating Cages, Tanjung Pinang City

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Kovács, Tamás, John M. C. Plane, Wuhu Feng, Tibor Nagy, Martyn P. Chipperfield, Pekka T. Verronen, Monika E. Andersson, David A. Newnham, Mark A. Clilverd y Daniel R. Marsh. "D-region ion–neutral coupled chemistry (Sodankylä Ion Chemistry, SIC) within the Whole Atmosphere Community Climate Model (WACCM 4) – WACCM-SIC and WACCM-rSIC". Geoscientific Model Development 9, n.º 9 (12 de septiembre de 2016): 3123–36. http://dx.doi.org/10.5194/gmd-9-3123-2016.

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Abstract. This study presents a new ion–neutral chemical model coupled into the Whole Atmosphere Community Climate Model (WACCM). The ionospheric D-region (altitudes ∼ 50–90 km) chemistry is based on the Sodankylä Ion Chemistry (SIC) model, a one-dimensional model containing 307 ion–neutral and ion recombination, 16 photodissociation and 7 photoionization reactions of neutral species, positive and negative ions, and electrons. The SIC mechanism was reduced using the simulation error minimization connectivity method (SEM-CM) to produce a reaction scheme of 181 ion–molecule reactions of 181 ion–molecule reactions of 27 positive and 18 negative ions. This scheme describes the concentration profiles at altitudes between 20 km and 120 km of a set of major neutral species (HNO3, O3, H2O2, NO, NO2, HO2, OH, N2O5) and ions (O2+, O4+, NO+, NO+(H2O), O2+(H2O), H+(H2O), H+(H2O)2, H+(H2O)3, H+(H2O)4, O3−, NO2−, O−, O2, OH−, O2−(H2O), O2−(H2O)2, O4−, CO3−, CO3−(H2O), CO4−, HCO3−, NO2−, NO3−, NO3−(H2O), NO3−(H2O)2, NO3−(HNO3), NO3−(HNO3)2, Cl−, ClO−), which agree with the full SIC mechanism within a 5 % tolerance. Four 3-D model simulations were then performed, using the impact of the January 2005 solar proton event (SPE) on D-region HOx and NOx chemistry as a test case of four different model versions: the standard WACCM (no negative ions and a very limited set of positive ions); WACCM-SIC (standard WACCM with the full SIC chemistry of positive and negative ions); WACCM-D (standard WACCM with a heuristic reduction of the SIC chemistry, recently used to examine HNO3 formation following an SPE); and WACCM-rSIC (standard WACCM with a reduction of SIC chemistry using the SEM-CM method). The standard WACCM misses the HNO3 enhancement during the SPE, while the full and reduced model versions predict significant NOx, HOx and HNO3 enhancements in the mesosphere during solar proton events. The SEM-CM reduction also identifies the important ion–molecule reactions that affect the partitioning of odd nitrogen (NOx), odd hydrogen (HOx) and O3 in the stratosphere and mesosphere.

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Heimonen, Kaisa, Jeremiah S. Lwanga, Marko Mutanen, Tommi Nyman y Heikki Roininen. "Spatial and temporal variation in community composition of herbivorous insects on Neoboutonia macrocalyx in a primary tropical rain forest". Journal of Tropical Ecology 29, n.º 3 (2 de abril de 2013): 229–41. http://dx.doi.org/10.1017/s0266467413000151.

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Abstract:Spatial and temporal variation of tropical insect communities has rarely been studied, although such variation influences estimates of global species richness. Therefore, we compared spatial and temporal variation of herbivorous insect communities on Neoboutonia macrocalyx trees among seven sites over 1 y in a primary tropical rain forest in Kibale National Park, Uganda. The distance between the study sites varied from 4.8 to 31.2 km and altitudinal differences ranged from 20 to 242 m. Permutational multivariate analysis of variance (PERMANOVA) revealed significant spatial changes in community composition of the herbivorous insects and study sites differed also in insect abundance (6.9–26.2 individuals m−2 of leaf area). This is likely to be caused by differences in vegetation, altitude and microclimate among the study sites. The similarity of insect species composition was negatively correlated with geographic and altitudinal distances among sites and positively correlated with the similarity of tree community composition. Species richness varied significantly between sampling dates, ranging from 33 to 41 species. Also community compositions changed between sampling dates, which likely follows from marked seasonal changes in climate and the phenology of other host plants used by the generalist insect species also living on Neoboutonia macrocalyx. In general our study supports the idea of high variability of herbivorous insect communities in primary rain forests even at a small spatial scale. This should be considered when estimations of insect biodiversity are made.

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Hargrove, J. W. "A theoretical study of the invasion of cleared areas by tsetse flies (Diptera: Glossinidae)". Bulletin of Entomological Research 90, n.º 3 (junio de 2000): 201–9. http://dx.doi.org/10.1017/s0007485300000328.

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Large-scale eradication campaigns against tsetse flies Glossina spp. are giving way to smaller operations aimed at disease and vector containment. There has been little discussion of the effects of these changes in policy. This study estimates the rate at which tsetse re-infect treated areas after the termination of control efforts. Movement is modelled as a diffusion process with a daily root mean square displacement (λ) of 0.2–1 km−1/2 and population growth as logistic with a growth rate (r) ≤1.5% day−1. Invasion fronts move as the product of λ and √r. For r = 0.75% day−1 a front advances at 2.5 km year−1for each 100 m increment in λ. If there are 0.001% survivors in 10% of the treated area, the population recovers to within 1% of the carrying capacity (K) within three years. If the control area is subject to invasion from all sides, a treated block of 10,000 km2 is effectively lost within two years – except at the lowest values of λ and r. Cleared areas of 100 km2 are lost in a year, as observed in a community-based suppression programme in Kenya. If the treated area is closed to re-invasion, but if there is a block where tsetse survive at 0.0001–0.1% of K, the population recovers within 3–4 years for up to 20 km outside the surviving block. If the surviving flies are more widely spread, re-infection is even more rapid. The deterministic approach used here over-estimates re-invasion rates at low density, but comparisons between control scenarios are still valid. Stochastic modelling would estimate more exactly rates of re-infection at near-zero population densities.

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Wang, Hongyong, Xiaohao Xu y Yifei Zhao. "Empirical analysis of aircraft clusters in air traffic situation networks". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, n.º 9 (25 de julio de 2016): 1718–31. http://dx.doi.org/10.1177/0954410016660870.

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The existing research on air traffic complexity ignores the effects of air traffic situation structure and, thus, cannot reflect the heterogeneous traffic density distribution in airspace. In this study, the structure of air traffic situation was characterized using the idea of community structure in complex networks. An aircraft cluster model was built, and an aircraft cluster discovery method based on depth-first traversal was proposed. The aircraft cluster division effect was comprehensively represented by cluster performance indices, including cohesion and stability. The routinely recorded radar data in two air traffic control sectors were collected to assess the cluster division results. Through statistics, the threshold intervals with 95% of best performance are 40–60 km and 20–50 km for the two sectors, respectively. The value 40 km was selected to further statistically characterize the aircraft clusters. Compared with K-means clustering, the proposed method does not require the predefined number of clusters and has high stability, which confirms its feasibility into cluster division in dynamic air traffic situation. The structural characteristics of aircraft clusters, including the average intra-cluster horizontal distance, number of clusters, and size and life cycle of clusters, were statistically analyzed. Comparison of cluster structures with the commonly used dynamic density index shows that in air traffic situation with relatively large number big size of clusters, the aircraft trajectory changes more frequently. Structural characterization of aircraft clusters is able to portray the nonuniformity of traffic density distribution, and contributes to comprehensive description of air traffic situation, thus providing a new prospect for analysis of air traffic complexity. Moreover, aircraft cluster division contributes to auto-identification of hot-spots on radar screen, and efficiently eliminates the workload imposed on controllers during judgment of these congestion hot-spots, thereby improving the air traffic operation efficiency.

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50

Croquer, Aldo, David Bone, Carolina Bastidas, Ruth Ramos y Elia García. "Monitoring coastal pollution associated with the largest oil refinery complex of Venezuela". PeerJ 4 (23 de junio de 2016): e2171. http://dx.doi.org/10.7717/peerj.2171.

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This study evaluated pollution levels in water and sediments of Península de Paraguaná and related these levels with benthic macrofauna along a coastal area where the largest Venezuelan oil refineries have operated over the past 60 years. For this, the concentration of heavy metals, of hydrocarbon compounds and the community structure of the macrobenthos were examined at 20 sites distributed along 40 km of coastline for six consecutive years, which included windy and calm seasons. The spatial variability of organic and inorganic compounds showed considerably high coastal pollution along the study area, across both years and seasons. The southern sites, closest to the refineries, had consistently higher concentrations of heavy metals and organic compounds in water and sediments when compared to those in the north. The benthic community was dominated by polychaetes at all sites, seasons and years, and their abundance and distribution were significantly correlated with physical and chemical characteristics of the sediments. Sites close to the oil refineries were consistently dominated by families known to tolerate xenobiotics, such as Capitellidae and Spionidae. The results from this study highlight the importance of continuing long-term environmental monitoring programs to assess the impact of effluent discharge and spill events from the oil refineries that operate in the western coast of Paraguaná, Venezuela.

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