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  • 1
    Language: English
    In: Plant and Soil, 2011, Vol.340(1), pp.7-24
    Description: Spatial prediction of soil organic matter is a global challenge and of particular importance for regions with intensive land use and where availability of soil data is limited. This study evaluated a Digital Soil Mapping (DSM) approach to model the spatial distribution of stocks of soil organic carbon (SOC), total carbon (C tot ), total nitrogen (N tot ) and total sulphur (S tot ) for a data-sparse, semi-arid catchment in Inner Mongolia, Northern China. Random Forest (RF) was used as a new modeling tool for soil properties and Classification and Regression Trees (CART) as an additional method for the analysis of variable importance. At 120 locations soil profiles to 1 m depth were analyzed for soil texture, SOC, C tot , N tot , S tot , bulk density (BD) and pH. On the basis of a digital elevation model, the catchment was divided into pixels of 90 m × 90 m and for each cell, predictor variables were determined: land use unit, Reference Soil Group (RSG), geological unit and 12 topography-related variables. Prediction maps showed that the highest amounts of SOC, C tot , N tot and S tot stocks are stored under marshland, steppes and mountain meadows. River-like structures of very high elemental stocks in valleys within the steppes are partly responsible for the high amounts of SOC for grasslands (81–84% of total catchment stocks). Analysis of variable importance showed that land use, RSG and geology are the most important variables influencing SOC storage. Prediction accuracy of the RF modeling and the generated maps was acceptable and explained variances of 42 to 62% and 66 to 75%, respectively. A decline of up to 70% in elemental stocks was calculated after conversion of steppe to arable land confirming the risk of rapid soil degradation if steppes are cultivated. Thus their suitability for agricultural use is limited.
    Keywords: Classification and Regression Trees (CART) ; Soil organic carbon (SOC) ; China ; Grassland
    ISSN: 0032-079X
    E-ISSN: 1573-5036
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  • 2
    Language: English
    In: Plant and Soil, 2010, Vol.331(1), pp.341-359
    Description: In order to identify the effects of land-use/cover types, soil types and soil properties on the soil-atmosphere exchange of greenhouse gases (GHG) in semiarid grasslands as well as provide a reliable estimate of the midsummer GHG budget, nitrous oxide (N 2 O), methane (CH 4 ) and carbon dioxide (CO 2 ) fluxes of soil cores from 30 representative sites were determined in the upper Xilin River catchment in Inner Mongolia. The soil N 2 O emissions across all of the investigated sites ranged from 0.18 to 21.8 μg N m -2  h -1 , with a mean of 3.4 μg N m -2  h -1 and a coefficient of variation (CV, which is given as a percentage ratio of one standard deviation to the mean) as large as 130%. CH 4 fluxes ranged from -88.6 to 2,782.8 μg C m -2  h -1 (with a CV of 849%). Net CH 4 emissions were only observed from cores taken from a marshland site, whereas all of the other 29 investigated sites showed net CH 4 uptake (mean: -33.3 μg C m -2  h -1 ). CO 2 emissions from all sites ranged from 3.6 to 109.3 mg C m -2  h -1 , with a mean value of 37.4 mg C m -2  h -1 and a CV of 66%. Soil moisture primarily and positively regulated the spatial variability in N 2 O and CO 2 emissions (R 2  = 0.15–0.28, P  〈 0.05). The spatial variation of N 2 O emissions was also influenced by soil inorganic N contents ( P  〈 0.05). By simply up-scaling the site measurements by the various land-use/cover types to the entire catchment area (3,900 km 2 ), the fluxes of N 2 O, CH 4 and CO 2 at the time of sampling (mid-summer 2007) were estimated at 29 t CO 2 -C-eq d -1 , -26 t CO 2 -C-eq d -1 and 3,223 t C d -1 , respectively. This suggests that, in terms of assessing the spatial variability of total GHG fluxes from the soils at a semiarid catchment/region, intensive studies may focus on CO 2 exchange, which is dominating the global warming potential of midsummer soil-atmosphere GHG fluxes. In addition, average GHG fluxes in midsummer, weighted by the areal extent of these land-use/cover types in the region, were approximately -30.0 μg C m -2  h -1 for CH 4 , 2.4 μg N m -2  h -1 for N 2 O and 34.5 mg C m -2  h -1 for CO 2 .
    Keywords: GHG fluxes ; Land-use/cover ; Semi-arid grassland ; Xilin River catchment
    ISSN: 0032-079X
    E-ISSN: 1573-5036
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  • 3
    Language: English
    In: Wildlife Research, 2011, Vol.38(7), p.541-550
    Description: Context: Common voles (Microtus arvalis) are the most common vertebrate pests in central European agriculture. During outbreaks common vole populations can increase to an enormous number of individuals; however, this outbreak risk varies regionally. Aims: In this study we tested whether topography and soil properties are suited to explain the regional variability in the outbreak risk of the common vole in Eastern Germany. This study provides the first detailed large-scale study of the association of site characteristics and small mammal outbreak risk at a regional scale. Methods: Data on common vole outbreaks were recorded by active burrow counts at 82 sampling sites in Eastern Germany from almost four decades. Data on topography and soil properties - i.e. groundwater fluctuation index, soil air capacity, saturated hydraulic conductivity, soil class and elevation - were obtained from soil maps and a digital elevation model in a geographic information system and were related to outbreak risk classes, applying classification and regression trees (CART). Based on these results a map of the outbreak risk was developed for the area. Key results: Classification and regression tree analyses revealed that the mean elevation, area-related percentage of Chernozem soils and soil air capacity were the site characteristics best suited to explain local variability in outbreak risk. In the northern German lowland, below an elevation of ~83 m above sea level, the outbreak risk is generally very low. The region of the central upland has an increased risk for outbreaks of common voles. Within the region of the central uplands the risk was again elevated if the area covered by Chernozem soils was higher than 36%, and increased further if the area covered by soils with a moderate soil air capacity was higher than 90%. Conclusions: Topography and soil properties, and accordingly the character of a landscape, are static parameters that affect the local risk of common vole outbreak. Further detailed field investigations of soil properties are required to link the variation in regional outbreak risk to site characteristics with relevance to common vole ecology. Implications: Areas of varying regional outbreak risk of common voles can be defined according to static site characteristics identified in this study. They can provide a spatial framework to relate dynamic parameters, such as meteorological parameters, as well as biological parameters, such as food availability, to common vole outbreaks. This could be used in the future to develop improved predictive models to forecast common vole outbreaks. Additional keywords: CART, Chernozem, digital soil mapping, GIS, risk map, rodent management.
    Keywords: CART; Chernozem; digital soil mapping; GIS; risk map; rodent management.
    ISSN: 1035-3712
    E-ISSN: 1448-5494
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  • 4
    Language: English
    In: American Heart Journal, August 2017, Vol.190, pp.12-18
    Description: Oral anticoagulation prevents ischemic strokes in patients with atrial fibrillation (AF). Early detection of AF and subsequent initiation of oral anticoagulation help to prevent strokes in AF patients. Implanted cardiac pacemakers and defibrillators allow seamless detection of atrial high rate episodes (AHRE), but the best antithrombotic therapy in patients with AHRE is not known. Stroke risk is higher in pacemaker patients with AHRE than in those without, but the available data also show that stroke risk in patients with AHRE is lower than in patients with AF. Furthermore, only a minority of patients with AHRE will develop AF, many strokes occur without a temporal relation to AHRE, and AHRE can reflect other arrhythmias than AF or artifacts. An adequately powered controlled trial of oral anticoagulation in patients with AHRE is needed. The on–vitamin K antagonist ral anticoagulants in patients with trial igh rate episodes (NOAH–AFNET 6 ) trial tests whether oral anticoagulation with edoxaban is superior to prevent the primary efficacy outcome of stroke or cardiovascular death compared with aspirin or no antithrombotic therapy based on evidence-based indications. The primary safety outcome will be major bleeding. NOAH–AFNET 6 will randomize 3,400 patients with AHRE, but without documented AF, aged ≥65 years with at least 1 other stroke risk factor, to oral anticoagulation therapy (edoxaban) or no anticoagulation. All patients will be followed until the end of this investigator-driven, prospective, parallel-group, randomized, event-driven, double-blind, multicenter phase IIIb trial. Patients will be censored when they develop AF and offered open-label anticoagulation. The sponsor is the Atrial Fibrillation NETwork (AFNET). The trial is supported by the DZHK (German Centre for Cardiovascular Research), the BMBF (German Ministry of Education and Research), and Daiichi Sankyo Europe. NOAH–AFNET 6 will provide robust information on the effect of oral anticoagulation in patients with atrial high rate episodes detected by implanted devices.
    Keywords: Medicine
    ISSN: 0002-8703
    E-ISSN: 1097-6744
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  • 5
    In: Revista Forestal Mesoamericana Kurú, 04/26/2013, Vol.10(24), p.14
    Description: An Acacia mangium Willd. progeny test conformed by 25 families from six derivate provenances was evaluated. The trial was established in San Carlos, northern from Costa Rica in year 2006, and evaluated in 2007 and in 2010. Genetic material came from breeding selections obtained by GENFORES, a tree improvement and gene conservation cooperative, in Costa Rica and Colombia. Each family was represented by 48 progenies, randomly distributed in four pairs within each of the six blocks of the trial. In 2010, DBH, survival rate, merchantable number of logs per tree, forking presence, forking height and log quality in the first four logs were evaluated. Based on these measurements, wood commercial volume per tree and hectare was estimated. Data was analyzed with SELEGEN software in order to obtain all genetic parameters from the breeding population. All traits, except survival rate, showed family mean heritability values over 0.62. Genetic gain in commercial volume per hectare was estimated as 31.24 %, when selecting as progenitors the two best individuals from the top 12 families at four-year old, which corresponds to an estimated commercial volume/ha at this age of 67.89 m3/ha, based on a growth rate of 16.97 m3/ha/year. The two Colombian provenances were significantly superior to the rest of the evaluated materials. Genetic correlations among traits showed that diameter growth rate is early expressed in this tree species, and therefore, could be used in future selections.
    Keywords: Tree Improvement ; Provenances ; Progeny Test ; Genetic Correlations ; Acacia Mangium ; San Carlos ; Costa Rica ; Mejoramiento Genético ; Procedencias ; Progenie ; Correlación Genética ; Acacia Mangium ; San Carlos ; Costa Rica;
    ISSN: Revista Forestal Mesoamericana Kurú
    E-ISSN: 2215-2504
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  • 6
    Language: Spanish
    In: Agronomía Mesoamericana, 01 June 2012, Vol.23(1)
    Description: Ganancia genética esperada en Acacia mangium en Los Chiles, zona norte de Costa Rica. Con el objetivo de seleccionar los materiales de mayor crecimiento y calidad de fuste en Acacia mangium, se evaluó un ensayo de progenie de Acacia mangium Willd. conformado por veinticinco familias.El ensayo fue establecido en Los Chiles, zona norte de CostaRica, en 2006 con evaluaciones en el 2007 y en 2010. Se utilizó material genético seleccionado por la Cooperativa de Conservación y Mejoramiento Genético Forestal “GENFORES”,en Costa Rica y Colombia. Cada familia estuvo representada por 48 progenies, plantadas en cuatro parejas distribuidas enforma aleatoria dentro de cada uno de los seis bloques delensayo. Se evaluó el diámetro a la altura de pecho “DAP”,incremento en DAP, adaptabilidad al sitio, número de trozas comerciales, bifurcación, altura de bifurcación, calidad de las primeras cuatro trozas. Se determinó el volumen de maderacomercial por árbol y hectárea. Los datos fueron analizadospor medio del software SELEGEN de EMBRAPA para obtenerlos parámetros genéticos. Todos los caracteres registraron valores de heredabilidad media familiar superiores a 0,68.Si se seleccionaran los dos mejores individuos dentro de las mejores doce familias, se obtendría una ganancia genética del40,8% en volumen comercial/ha a los cuatro años de edad.Esta ganancia corresponde a un volumen comercial de 91,65m3/ha, a una tasa de 22,9 m3/ha/año. Las dos procedencias derivadas de Colombia son significativamente superiores a los demás materiales evaluados. El análisis de correlación genética entre caracteres muestra que la tasa de crecimiento diamétrico se expresa desde temprana edad en esta especie, lo que podría ser utilizado a futuro en una selección a menor edad.
    Keywords: Mejoramiento Genético ; Procedencias ; Progenie ; Correlación Genética
    ISSN: 10217444
    E-ISSN: 2215-3608
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  • 7
    Language: English
    In: Journal of Pharmaceutical Sciences, November 1964, Vol.53(11), pp.1333-1337
    Description: Three pathways leading to the methyl ethers of 3,3′,5‐triiodo‐D and L‐thyronine were explored. In these syntheses the acetyl, benzoyl, and trifluoroacetyl groups were studied as suitable amine‐protecting groups, thus providing a number of hitherto unreported thyronine derivatives. Consideration of the over‐all yields and the quality of the products from the various reaction sequences showed that the acetyl group was best suited for the protection of the amino group in these syntheses.
    Keywords: Pharmacy, Therapeutics, & Pharmacology
    ISSN: 0022-3549
    E-ISSN: 1520-6017
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  • 8
    Article
    Article
    Language: English
    In: Journal of Pharmaceutical Sciences, 11/1964, Vol.53(11), pp.1333-1337
    ISSN: 00223549
    Source: Wiley (via CrossRef)
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  • 9
    Language: English
    In: The Journal of Organic Chemistry, 08/1959, Vol.24(8), pp.1137-1138
    ISSN: 0022-3263
    E-ISSN: 1520-6904
    Source: American Chemical Society (via CrossRef)
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  • 10
    In: European Heart Journal, 2018, Vol. 39(32), pp.2942-2955
    Description: Abstract Aims It is recommended to perform atrial fibrillation ablation with continuous anticoagulation. Continuous apixaban has not been tested. Methods and results We compared continuous apixaban (5 mg b.i.d.) to vitamin K antagonists (VKA, international normalized ratio 2–3) in atrial fibrillation patients at risk of stroke a prospective, open, multi-centre study with blinded outcome assessment. Primary outcome was a composite of death, stroke, or bleeding (Bleeding Academic Research Consortium 2–5). A high-resolution brain magnetic resonance imaging (MRI) sub-study quantified acute brain lesions. Cognitive function was assessed by Montreal Cognitive Assessment (MoCA) at baseline and at end of follow-up. Overall, 674 patients (median age 64 years, 33% female, 42% non-paroxysmal atrial fibrillation, 49 sites) were randomized; 633 received study drug and underwent ablation; 335 undertook MRI (25 sites, 323 analysable scans). The primary outcome was observed in 22/318 patients randomized to apixaban, and in 23/315 randomized to VKA {difference −0.38% [90% confidence interval (CI) −4.0%, 3.3%], non-inferiority P = 0.0002 at the pre-specified absolute margin of 0.075}, including 2 (0.3%) deaths, 2 (0.3%) strokes, and 24 (3.8%) ISTH major bleeds. Acute small brain lesions were found in a similar number of patients in each arm [apixaban 44/162 (27.2%); VKA 40/161 (24.8%); P = 0.64]. Cognitive function increased at the end of follow-up (median 1 MoCA unit; P = 0.005) without differences between study groups. Conclusions Continuous apixaban is safe and effective in patients undergoing atrial fibrillation ablation at risk of stroke with respect to bleeding, stroke, and cognitive function. Further research is needed to reduce ablation-related acute brain lesions.
    Keywords: Atrial Fibrillation ; Ablation ; Anticoagulation ; Bleeding ; Stroke ; Brain Mri
    ISSN: 0195-668X
    E-ISSN: 1522-9645
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