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Assessing the costs and benefits of improved land management practices in three watershed areas in Ethiopia

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International Soil and Water Conservation Research 2016年第1期4卷 20-29页

作者： Abonesh Tesfaye Roy Brouwer pieter van der Zaag Workneh Negatu Department of Environmental Economics Institute for Environmental StudiesVU University AmsterdamDe Boelelaan 10871081 HV AmsterdamThe Netherlands UNESCO–IHE Institute for Water EducationDelftThe Netherlands Delft University of Technology DelftThe Netherlands Addis Ababa University College of Development StudiesCentre for Rural DevelopmentAddis AbabaEthiopia

Unsustainable land use management and the resulting soil erosion are among the most pervasive problems in rural Ethiopia,where most of the country’s people live,jeopardizing food *** various efforts to introduce soil conservation measures and assess their costs and benefits,it is unclear how efficient these measures are from an economic point of view in securing food *** paper examines the costs and benefits of three soil conservation measures applied in the country in three different rural districts facing different degrees of soil erosion problems using survey data collected from 750 farm households.A production function is estimated to quantify the costs and benefits of more sustainable land use management *** show that the soil conservation measures significantly increase productivity and hence food *** the costs and benefits,the results indicate that implementing soil conservation measures would benefit farm communities in the case study areas through increased grain productivity and food security.

关键词： Soil conservation Cost–benefit analysis Cobb–Douglas production function Blue Nile Ethiopia

Disturbance increases high tide travel distance of a roosting shorebird but only marginally affects daily energy expenditure

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Avian Research 2019年第3期10卷 294-304页

作者： Hans Linssen Martijn van de pol Andrew M.Allen Mitzi Jans Bruno J.Ens Karen L.Krijgsveld Magali Frauendorf Henk-Jan van der Kolk Department of Animal Ecology Netherlands Institute of Ecology6708PB WageningenThe Netherlands Resource Ecology Group Wageningen University & Research6708PB WageningenThe Netherlands Centre for Avian Population Studies Droevendaalsesteeg 106708PB WageningenThe Netherlands Department of Animal Ecology and Physiology Radboud University6500GL NijmegenThe Netherlands Sovon-Texel Sovon Dutch Centre for Field Ornithology1790AB Den BurgThe Netherlands Nature Bureau Royal Netherlands Air Force4820BB BredaThe Netherlands

Background:Anthropogenic disturbance can negatively affect an animal's energy budget by evoking movement *** research focuses mainly on immediate displacement as a disturbance effect,since this can be easily observed in the field. However, effects on movement over longer timescales are poorly examined and it is largely unknown if and to what extent they reflect immediate ***-term responses could for example be larger than immediate responses if birds, after disturbance, return to the original location and thereby travel twice the immediate disturbed distance. Methods:We combined GPS tracking data with observational data to quantify the effects of anthropogenic (air force and walkers) and non-anthropogenic disturbances on distances travelled by roosting Eurasian Oystercatchers (Haematopus ostralegus) during the non-breeding season. We compared immediate displacement after a disturbance with distance travelled during the entire high tide period (longer-term response), while accounting for environmental ***,we calculated energy expenditure due to disturbance based on observed disturbance ***:Disturbance resulted in an immediate displacement response of ~200 m (median).Air force disturbances tended to yield larger immediate responses than walker and,especially,than non-anthropogenic ***-term responses and immediate responses were approximately similar,suggesting that,over longer timescales,spatial disturbance effects in the study area remain confined to immediate ***,disturbances were infrequent (0.17 disturbances per bird per hour) and most disturbances were of natural origin (62%).Consequently, anthropogenic disturbance of roosting oystercatchers in the study area on average costs 0.08% of the daily energy expenditure. Conclusions:Our results suggest that immediate spatial responses to disturbance can be a useful proxy for spatial responses over longer *** the non-exha

关键词： Biologging Disturbance Haematopus ostralegus High tide roost Movement ecology Shorebird

Poroelastic Modelling of Gravitational Compaction

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Open Journal of Physical Chemistry 2019年第3期9卷 126-169页

作者： pieter Broer van der Weg Unilever R & D Vlaardingen The Netherlands

A dynamic in-silico model captures the kinetics of 1-d gravity driven instabilities, in gravity or centrifuge, of fluid-infiltrated poroelastic media in a partial differential equation (pde). The pde yields the porosity profile over height and time for the given initial and boundary conditions, during slow compaction in counter-current fluid drainage. Processes captured are amongst others sedimentation, creaming and subsidence. The most important limiting prerequisite is that the incompressible dispersed medium is sufficiently structured and/or concentrated that it compacts during slow drainage, without segregation in sizes or in components. For Unilever, modeling of gravitational instability of products is important to quantify or extrapolate long time behavior during shelf life or use centrifuge data to quickly predict long term shelf performance of products.

关键词： Poroelastic Compaction Consolidation Gravity Centrifuge Sedimentation Creaming Subsidence Emulsion Dispersion

Reduction of Environmental Impact of Drum Machine Washing

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Journal of Applied Mathematics and Physics 2020年第1期8卷 132-157页

作者： pieter Broer van der Weg (Peter) Retired VU Amsterdam Shell R & D Rijswijk Stork DI Boxmeer Unilever R & D Vlaardingen Vlaardingen The Netherlands

An improvement of efficiency of the horizontally rotating drum washing machine is possible by using a more open type of drum, essentially without suds in the annulus, by using a pump to wet the clothes during rotation and fall. Modelling and simulation are used to quantify these claims and further optimize the design of the horizontal washing machine. The flow of suds inside the deforming clothes at impact with the drum is calculated. The wash performance is shown to be largely proportional to the open perforation area in the drum. The traditional design uses 1/8 of drum area for the perforation holes. A significant reduction of water, detergent, electrical energy, and wash time, with parity in wash performance, provides a step towards a cleaner and more sustainable future.

关键词： Drum Wash Machine Design Efficiency Poroelastics Darcy Simulation Modelling

Developments in genetic modification of cattle and implications for regulation, safety and traceability

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Frontiers of Agricultural Science and Engineering 2020年第2期7卷 136-147页

作者： Jan pieter van der BERG Gijs A.KLETER Evy BATTAGLIA Martien A.M.GROENEN Esther J.KOK Wageningen Food Safety Research Wageningen University and Research6700 AE Wageningenthe Netherlands Animal Breeding and Genomics Wageningen University and Research6700 AH Wageningenthe Netherlands

Genetic modification techniques,in particular novel gene editing technologies,hold the yet unfulfilled promise of altering genetic traits in farm animals more efficiently than by crossbreeding,allowing for a more rapid development of new cattle breeds with distinct *** editing technologies allow for the directed alteration of specific traits and thereby have the potential to enhance,for instance,disease resilience,production yield and the production of desired substances in *** potential implications of these technological advancements,which are often combined with animal cloning methods,are discussed both for animal health and for consumer safety,also with consideration of available methods for the detection and identification of the related products in the food supply ***,an overview is provided of current regulatory approaches in the European Union(EU)and major countries exporting beef to the EU,for products from animals bred through established practices as well as modern biotechnologies.

关键词： cattle food safety gene editing genetic modification GMO detection regulation

One-Step Reverse Osmosis Based on Riverbank Filtration for Future Drinking Water Purification

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Engineering 2022年第2期8卷 27-34页

作者： Yujia Zhai Gang Liu Walter G.J.van der Meer Oasen Drinkwater Gouda 2800 ACNetherlands Faculty of Science and Technology University of TwenteEnschede 7500 AENetherlands Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Sanitary Engineering Research Group Department of Water ManagementFaculty of Civil Engineering and GeosciencesDelft University of TechnologyDelft 2600 GANetherlands

The presence of newly emerging pollutants in the aquatic environment poses great challenges for drink-ing water treatment *** to their low concentrations and unknown characteristics,emerging pol-lutants cannot be efficiently removed by conventional water treatment processes,making technically,economically,and environmentally friendly water purification technologies increasingly *** article introduces a one-step reverse osmosis(OSRO)concept consisting of riverbank filtration(RBF)and reverse osmosis(RO)for drinking water *** OSRO concept combines the relatively low-cost natural pretreatment of river water with an advanced engineered purification *** pro-vides a continuous natural source of water with stable water quality and a robust barrier for *** the pre-removal of particles,organic matter,organic micro-pollutants(OMPs),and microbes,RBF becomes an ideal source for a purification system based on RO membranes,in comparison with the direct intake of surface *** treatment removes almost 99.9%of the particles,pathogens,viruses,and OMPs,as well as the vast majority of nutrients,and thus meets the requirements for the chlorine-free delivery of drinking water with high *** OSRO treatment is cost effective com-pared with the standard conventional series of purification steps involving sprinkling filters,softening,and activated *** bank filtration(ABF),which functions as an artificial recharge in combi-nation with a sand filtration system,is proposed as an alternative for RBF in the OSRO concept to supply drinking water from locally available *** is also suggested that the OSRO concept be imple-mented with wind power as an alternative energy source in order to be more sustainable and *** OSRO-based decentralized water system is proposed for water reclaiming and *** is suggested that future water treatment focus on the combination of natural and engineered systems to pro

关键词： Drinking water treatment River bank filtration Reverse osmosis Artificial bank filtration Water reclamation and reuse

Acute Respiratory Distress after Knee Arthroplasty Due to Undiagnosed Atrial Myxoma

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Open Journal of Anesthesiology 2012年第3期2卷 90-92页

作者： Zeest Khan Bo Yang Hari Mallidi pieter van der Starre Cardiothoracic Surgery Stanford University School of Medicine Stanford CA USA. Departments of Anesthesia Stanford University School of Medicine Stanford CA USA

Acute postoperative respiratory distress may be caused by pneumonia, pulmonary embolism, heart failure, pneumothorax or atelectasis. We present s case report of a 78-year-old female patient who developed acute respiratory distress one day following knee arthroscopy. Because of the suspicion of pulmonary embolism, a computed tomographic angiography was made, showing the presence of an unexpected large left atrial mass, suggestive for a myxoma. She underwent successful resection of a 10 × 5 cm myxoma one week later. The report discusses the clinical manifestations of an atrial myxoma and its potentially fast growth. Bedside echocardiography should be considered the preferred diagnostic modality in case of acute postoperative respiratory distress.

关键词： Non-Cardiac Surgery Acute Respiratory Distress Left Atrial Myxoma Echocardiography Cardiac Surgery

Colour-ring wear and loss effects in citizen science mark-resighting studies

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Avian Research 2019年第2期10卷 148-162页

作者： Andrew M.Allen Bruno J.Ens Martijn van de pol Henk van der Jeugd Magali Frauendorf Henk-Jan van der Kolk Kees Oosterbeek Jeroen Nienhuis Eelke Jongejans Department of Animal Ecology and Physiology Radboud University6500 GL NijmegenThe Netherlands Sovon Dutch Centre for Field Ornithology 6503 GANijmegen and Sovon-Texel1790 AB Den BurgThe Netherlands Department of Animal Ecology Netherlands Institute of Ecology NIOOKNAW6708 PB WageningenThe Netherlands Dutch Centre for Avian Migration and Demography 6700 AB WageningenThe Netherlands Centre for Avian Population Studies WageningenThe Netherlands

Background: Ring wear and loss may have important consequences for mark-recapture studies that aim to estimate survival trends. Our study quantifies the rates of wear and loss from a long-running colour-ringing project of the Eurasian Oystercatcher (Haematopus ostralegus) in the Netherlands. Methods: Our analysis included 8909 colour-ringed oystercatchers with 118,071 resightings, predominantly ringed and observed by citizen scientists. We quantified how ring wear and loss may vary with ring colour and age, and how this may impact resighting probabilities. We then determined how ring loss may impact survival estimates and resighting probabilities of mark-recapture models by simulating four scenarios of how citizen scientists may resight and report birds with lost colour rings. Results: Annual rates of colour ring loss averaged 2.5% compared with 1% for ring wear, but lost rings also had a higher reporting probability (31.2%) than worn rings (10.3%). Lost rings may not directly impact survival estimates since 50% of oystercatchers with lost rings could still be uniquely identified. Ring wear and loss rapidly increased between 10 and 15 years after ringing. Rates of ring loss were comparable amongst ring colours, but the wear rate appeared higher for red and white rings compared to other colours. Rates of ring wear and loss varied significantly amongst different regions in our study, which were characterised as having different habitat features. Differential rates of ring wear may have important implications for studies conducted over large geographical scales or of multiple species. Conclusions: Based on simulations of ring loss in our population, estimates of apparent survival may be 0.3–1.2% lower whilst the impact of ring wear was deemed even lower. We developed a table of recommendations containing advice for ring fitting, data collection, study design, and mark-recapture analyses, so that future colour-ringing studies can benefit from our experiences in collecti

关键词： Bias Bird migration Citizen science Colour-ring Mark-recapture Shorebirds Survival

The role of the pollination niche in community assembly of Erica species in a biodiversity hotspot

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Journal of Plant Ecology 2017年第4期10卷 634-648页

作者： Roderick W.Bouman Sandy-Lynn Steenhuisen Timotheüs van der Niet Naturalis Biodiversity Center Understanding Evolution GroupDarwinweg 42333 CR LeidenThe Netherlands Leiden University Sylviusweg 722333 BE LeidenThe Netherlands Hortus Botanicus Leiden 5e Binnenvestgracht 82311 VH LeidenThe Netherlands Department of Biological Sciences University of Cape TownPrivate Bag X3Rondebosch 7701South Africa School of Life Sciences University of KwaZulu-NatalPrivate Bag X01Scottsville 3209South Africa

Aims Closely related species frequently co-occur in plant *** role of niche partitioning for allowing their coexistence has been called into question,but most studies on community ecol-ogy neglect pollination as a niche component,and thus poten-tially underestimate niche ***,we investigate the importance of the pollination niche for determining coexistence in a biodiversity *** specifically test whether co-flowering insect-pollinated species of Erica,the most species-rich plant genus of the South African Cape Floristic Region,are characterized by dif-ferent functional floral traits and different specialized pollination *** Communities of co-flowering Erica species were studied at three sites in the fynbos biome in the Western Cape of South *** focused on five species with flowers that conform to an insect pol-lination *** assessed whether floral traits important for pollinator attraction and mechanical fit overlap by comparison of scent(gas chromatography coupled with mass spectrometry),col-our(spectrophotometry and models of bee vision),nectar volume and concentration and corolla *** partitioning was quantified by comparison of floral visitor profiles and pollinator importance,calculated as the product of visitation rate,number of flowers probed per visit and pollen load for each functional visitor group among species within *** effects of com-petition were assessed by comparing visitation rates both directly and using anther ring disturbance as a proxy for lifetime *** Findings Floral phenotypes differed among species within communities in all functional *** assemblages were diverse,including ants,beetles,flies,honeybees,moths and solitary ***,the Cape honeybee,Apis mellifera capensis,was the main pollinator of all but one Erica *** visitation rates were significantly lower for *** and *** relative to congene

关键词： Cape Floristic Region coexistence floral traits heaths pollination niche