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Assessing Soil Properties and landforms in the Mai-Negus Catchment, Northern Ethiopia

Pedosphere 2016年第5期26卷 745-759页

作者： gebreyesus Brhane TESFAHUNEgN lulseged TAMENE paul l.g.vlek College of Agriculture Aksum University-Shire Campus Center for Development Research (ZEF) University of Bonn International Center for Tropical Agriculture (CIAT) Chitedze Agricultural Research Station

Soil degradation is a serious environmental problem in Ethiopia. However, little information is documented on indicators such as variations in soil properties across different landforms in a catchment. This study was aimed to assess soil properties and their changes across sites with different erosion statuses, and identify landscape positions that require prior management attention in the Mai-Negus catchment, northern Ethiopia. Three types of erosion-status sites(stable, eroding and aggrading) were identified using reconnaissance surveys, and then the corresponding soil samples were collected and analyzed. The major soil properties were significantly varied(P ≤ 0.05) among the three erosion-status sites. The highest soil p H, organic carbon, total nitrogen, cation exchange capacity, iron and zinc were recorded from the aggrading sites in the reservoir and valley landforms of the study catchment. A higher bulk density was generally recorded in the eroding sites, whereas a lower value was observed in the aggrading sites. The highest sand content was observed in the eroding sites of the mountain followed by the central ridge landform. The paired mean difference and the correlation matrix of most soil properties between the different erosion statuses also showed significant differences. About 95% of the erosionstatus sites were correctly classified by the discriminant function, indicating that the field survey-based classification was acceptable for decision making. On the basis of this study, suitable interventions should thus be introduced to the prioritized landforms, which are the mountain and central ridge, and eroding sites with severely degraded soil properties across the catchment.

关键词： aggrading site discriminant function eroding site erosion status landscape soil property variability stable site

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Performance of Farmland Terraces in Maintaining Soil Fertility： A Case of lake Maybar Watershed in Wello, Northern Highlands of Ethiopia

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Journal of life Sciences 2012年第11期6卷 1251-1261页

作者： Shimeles Damene lulseged Tamene paul l.g. vlek Center for Development Research (ZEF) University of Bonn Bonn D-53113 Germany International Center for Tropical Agriculture (CIA T) Chitedze Agricultural Research Station Lilongwe Malawi

Soil-erosion-induced land degradation is a great challenge in the Ethiopian highlands. Consequently, the government has invested in soil and water conservation measures to tackle the problem where farmland terracing is one of the commonly implemented measures in the country. The purpose of this study was to analyze the role of farmland terracing in maintaining soil fertility and to evaluate its performance within a terrace, across terrace age and slope of terrain. The study was conducted in the lake Maybar watershed in Wello, northern Ethiopia. Composite topsoil samples were collected from plots representing four slope categories across the terrain and three positions within a terrace. The samples were analyzed for selected soil physico-chemical properties and statistically tested using ANOVA （analysis of variance）. The study revealed that soil pH （△pH [H2O] = 0.6）, exchangeable K＋（△K＋ = 0.33 cmol（＋）/kg） and clay （9%） content significantly increased towards the lower terrain position. Unlike other studies, all soil properties except bulk density （△ 0.40 g/cm3） showed non-significant differences within a terrace. Bench terrace formation reduced soil fertility gradients within a terrace for which it has been commented. Soil fertility also showed very slight change across terrace age, which indicates terracing reduced erosion-induced soil and nutrient loss. However, in order to optimize impact of farmland terracing on soil fertility maintenance, terracing should be complemented by fertility amendment considering site-specific conditions.

关键词： Farmland terrace terrain Wello Ethiopia soil degradation soil fertility.

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Personal Information Self-Management:A Survey of Technologies Supporting Administrative Services

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Journal of Computer Science & Technology 2021年第3期36卷 664-692页

作者： paul Marillonnet Maryline laurent Mikaël Ates Entr'ouvert Paris 75014France SAMOVAR Télécom SudParisInstitut Polytechnique de ParisEvry 91000France

This paper presents a survey of technologies for personal data self-management interfacing with administrative and territorial public service *** classifies a selection of scientific technologies into four categories of solutions:Personal Data Store(PDS),Identity Manager(IdM),Anonymous Certificate System and Access Control Delegation *** category,along with its technological approach,is analyzed thanks to 18 identified functional criteria that encompass architectural and communication aspects,as well as user data lifecycle *** originality of the survey is ***,as far as we know,there is no such thorough survey covering such a panel of a dozen of existing ***,it is the first survey addressing Personally Identifiable Information(PII)management for both administrative and private service ***,this paper achieves a functional comparison of solutions of very different technical *** outcome of this paper is the clear identification of functional gaps of each *** a result,this paper establishes the research directions to follow in order to fill these functional gaps.

关键词： personal information management privacy enforcement user-centric solution technological survey

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Macroinvertebrates in the bed sediment of the Yellow River

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International Journal of Sediment Research 2011年第3期26卷 255-268页

作者： paul g.ClOSE Centre of Excellence in Natural Resource Management The University of Western AustraliaP.O.Box 5771AlbanyWestern Australia 6330Australia

Extensive agricultural,industrial and urban development in the Yellow River,China,have modified the sediment-water balance,flow and inundation regimes,longitudinal connectivity,integrity of riparian vegetation,and water *** assemblages in the bed sediment of main channel and major reservoirs of the Yellow River are described in detail for the first time.A total of 74 taxa comprising 17 taxa of oligochaetes,48 taxa of aquatic insects,5 taxa of molluscs,and 4 taxa of other animals were recorded.A range of feeding guilds were represented,including, collector-gatherers(32 taxa),predators(17 taxa),scrapers(16 taxa),shredders(6 taxa)and collector-filterers(2 taxa).Both the mean density and biomass of macroinvertebrates were significantly higher in sites located in the artificial reservoirs compared with the main river channel. Assemblages varied spatially;Oligochaetes dominated assemblages in upper reaches,insects dominated in middle reaches and other animals(***)dominated in lower reaches. Collector-gatherers were dominant throughout the entire *** analysis identified five site-groups on the basis of macroinvertebrate presence/absence:downstream of reservoirs;vegetated sites;reservoir sites;polluted sites,and;lower-reach *** macroinvertebrate richness,density and biomass,compared with other similar large rivers,were attributed to modification of the sediment-water balance and associated disturbance of benthic ***,stability of sediment and sediment concentration combined to influence the distribution of *** knowledge will substantially benefit the recent focus on the health and environmental water requirements of the Yellow River.

关键词： Macroinvertebrates Species composition Distribution pattern Sediment The Yellow River

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Distinguishing normal brain aging from the development of Alzheimer＇s disease：inflammation,insulin signaling and cognition

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Neural Regeneration Research 2018年第10期13卷 1719-1730页

作者： paul Denver paula l.McClean greater los Angeles Veterans Affairs Healthcare System West Los Angeles Medical Center and Department of NeurologyUniversity of CaliforniaLos AngelesCAUSA Centre for Molecular Biosciences University of UlsterColeraine Northern Ireland UK Northern Ireland Centre for Stratified Medicine ClinicalTranslational and Research Innovation Centre (C-TRIC)University of UlsterDerry/Londonderry Northern Ireland UK

As populations age, prevalence of Alzheimer＇s disease（AD） is rising. Over 100 years of research has provided valuable insights into the pathophysiology of the disease, for which age is the principal risk factor. However, in recent years, a multitude of clinical trial failures has led to pharmaceutical corporations becoming more and more unwilling to support drug development in AD. It is possible that dependence on the amyloid cascade hypothesis as a guide for preclinical research and drug discovery is part of the problem. Accumulating evidence suggests that amyloid plaques and tau tangles are evident in non-demented individuals and that reducing or clearing these lesions does not always result in clinical improvement. Normal aging is associated with pathologies and cognitive decline that are similar to those observed in AD, making differentiation of AD-related cognitive decline and neuropathology challenging. In this mini-review, we discuss the difficulties with discerning normal, age-related cognitive decline with that related to AD. We also discuss some neuropathological features of AD and aging, including amyloid and tau pathology, synapse loss, inflammation and insulin signaling in the brain, with a view to highlighting cognitive or neuropathological markers that distinguish AD from normal aging. It is hoped that this review will help to bolster future preclinical research and support the development of clinical tools and therapeutics for AD.

关键词： Alzheimer's disease aging inflammation cognitive function spatial learning insulin signaling synapses cytokines

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A PERISHABlE INVENTORY SYSTEM WITH SERVICE FACIlITIES, MAP ARRIVAlS AND PH- SERVICE TIMES

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Journal of Systems Science and Systems Engineering 2007年第1期16卷 62-73页

作者： paul MANUEl B. SIVAKUMAR g. ARIVARIgNAN Department of Information Science Kuwait University Kuwait. Department of Applied Mathematics and Statistics School of Mathematics Madurai Kamaraj University Madurai Tamilnadu India

We consider a continuous review perishable （s,S） inventory system with a service facility consisting of a waiting hall of finite capacity and a single server. We assume two types of customers, ordinary and negative, arrive according to a Markovian Arrival Process （MAP）. An ordinary customer joins the queue and a negative customer instead of joining the queue removes one ordinary customer from the queue. The removal rule adopted in this paper is RCE （removal of a customer from the end）. The individual customer＇s unit demand is satisfied after a random time of service which is assumed to have a phase-type distribution. The life time of each item and the lead time of the reorders have been assumed to be independent exponential distributions. The joint probability distribution of the number of customers in the system and the inventory level is obtained for the steady state case. Various stationary system performance measures are computed and the total expected cost rate is calculated. The results are illustrated numerically.

关键词： Stochastic inventory Markovian demands service facility positive lead time negative customers

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Edge-Aware level Set Diffusion and Bilateral Filtering Reconstruction for Image Magnification

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Journal of Computer Science & Technology 2009年第4期24卷 734-744页

作者：黄华臧彧 paul l.Rosin 齐春 School of Electronics and Information Engineering Xi'an Jiaotong University Xi'an 710049 China School of Computer Science Cardiff University Cardiff U.K.

In this paper we propose an image magnification reconstruction method. In recent years many interpolation algorithms have been proposed for image magnification, but all of them have defects to some degree, such as jaggies and blurring. To solve these problems, we propose applying post-processing which consists of edge-aware level set diffusion and bilateral filtering. After the initial interpolation, the contours of the image are identified. Next, edge-aware level set diffusion is applied to these significant contours to remove the jaggies, followed by bilateral filtering at the same locations to reduce the blurring created by the initial interpolation and level set diffusion. These processes produce sharp contours without jaggies and preserve the details of the image. Results show that the overall RMS error of our method barely increases while the contour smoothness and sharpness are substantially improved.

关键词： computer application image magnification reconstruction edge-aware level set diffusion bilateral filtering

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The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： paul B.Wignall David P.g.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(lming evidence for rapid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

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Protective effects of trilinolein extracted from Panax notoginseng against cardiovascular disease

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Acta Pharmacologica Sinica 2002年第12期23卷 104-109页

作者： paul CHAN,g Neil THOMAS,Brian TOMlINSON Division of Cardiovascular Medicine Taipei Medical College Affiliated Taipei Wan Fang Hospital Taipei China Department of Medicine and Therapeutics The Chinese University of Hong Kong Prince of Wales Hospital Shatin NT Hong Kong SAR China Department of Medicine and Therapeutics The Chinese University of Hong Kong Prince of Wales Hospital Shatin NT Hong Kong SAR China

Trilinolein is a triacylglycerol purified from a commonly used traditional Chinese medicine Panax notoginseng. Trilinolein has been reported to provide a number of beneficial effects including reducing thrombogenicity and arrhythmias and increasing erythrocyte deformability. Additionally, trilinolein has been reported to be an antioxidant, which can counteract free radical damage associated with atherogenesis, and myocardial damage seen with is-chaemia and reperfusion. These pharmacologic effects may explain the perceived benefits derived from treating circulatory disorders with the herb over the centuries.

关键词： antioxidants cardiovascular system Chinese traditional medicine trilinolein Panax notoginseng

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Scaling the Microphysics Equations and Analyzing the Variability of Hydrometeor Production Rates in a Controlled Parameter Space

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Advances in Atmospheric Sciences 2002年第4期19卷 619-650页

作者： Chungu lu paul Schultz and gerald l Browning NOAA Forecast Systems laboratory Boulder USA Cooperative Institute for Research in the Atmosphere Colorado State University Fort Collins USA

A set of microphysics equations is scaled based on the convective length and velocity scales. Comparisons are made among the dynamical transport and various microphysical processes. From the scaling analysis, it becomes apparent which parameterized microphysical processes present off-scaled influences in the integration of the set of microphysics equations. The variabilities of the parameterized microphysical processes are also studied using the approach of a controlled parameter space. given macroscopic dynamic and thermodynamic conditions in different regions of convective storms, it is possible to analyze and compare vertical profiles of these processes. Bulk diabatic heating profiles for a cumulus convective updraft and downdraft are also derived from this analysis. From the two different angles, the scale analysis and the controlled-parameter space approach can both provide an insight into and an understanding of microphysics parameterizations.

关键词： cloud microphysical parameterization scale analysis controlled parameter space numerical weather prediction

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