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Hepatobiliary Surgery and Nutrition 2023年第6期12卷 919-922页

作者： Lisa m.van Velsen milan j.Sonneveld Karel j.van Erpecum Department of Gastroenterology and Hepatology Erasmus University Medical CenterRotterdamThe Netherlands Department of Gastroenterology and Hepatology University Medical Center UtrechtUtrechtThe Netherlands

Chronic hepatitis B(CHB)remains a major global health problem with approximately 258 million infected individuals(1).Hepatocellular carcinoma(HCC)is one of the major and most deadly consequences of *** cirrhotic patients are at risk of *** previous studies have also revealed a consistent association between higher hepatitis B virus(HBV)DNA levels and increased HCC risk.

关键词： Hepatocellular carcinoma(HCC) entecavir tenofovir chronic hepatitis B(CHB)

Scalable gas-phase processes to create nanostructured particles

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Particuology 2010年第6期8卷 572-577页

作者： j.Ruud van Ommen Caner U.Yurteri Naoko Ellis Erik m.Kelder Delft University of Technology Department of Chemical EngineeringJulianalaan 1362628 BL DelftThe Netherlands University of British Columbia Department of Chemical and Biological Engineering2360 East MallVancouverB.C.Canada V6T 1Z3

The properties of nanoparticles are often different from those of larger grains of the same solid material because of their very large specific surface area. This enables many novel applications, but properties such as agglomeration can also hinder their potential use. By creating nanostructured particles one can take optimum benefit from the desired properties while minimizing the adverse effects. We aim at developing high-precision routes for scalable production of nanostructured particles. Two gas-phase synthesis routes are explored. The first one - covering nanoparticles with a continuous layer - is carried out using atomic layer deposition in a fluidized bed. Through fluidization, the full surface area of the nanoparticles becomes available. With this process, particles can be coated with an ultra-thin film of constant and well-tunable thickness. For the second route - attaching nanoparticles to larger particles - a novel approach using electrostatic forces is demonstrated. The micron-sized particles are charged with one polarity using tribocharging. Using electrospraying, a spray of charged nanoparticles with opposite polarity is generated. Their charge prevents agglomeration, while it enhances efficient deposition at the surface of the host particle. While the proposed processes offer good potential for scale-up, further work is needed to realize large-scale processes.

关键词： Nanoparticles Nanocomposite materials Coating Films Particle coating Atomic layer deposition Core-shell particles Electrospraying Electrohydrodynamic atomization Electrostatic forces Fluidization

Gas–solid interaction force from direct numerical simulation (DNS) of binary systems with extreme diameter ratios

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Particuology 2009年第4期7卷 233-237页

作者： S. Sarkar S.H.L. Kriebitzsch m.A. van der Hoef j.A.m. Kuipers Department of Science and Technology University of Twente P.O. Box 217 7500 AE Enschede The Netherlands

Fluid-particle systems as commonly encountered in chemical, metallurgical and petroleum industries are mostly polydisperse in nature. However, the relations used to describe fluid-particle interactions are originally derived from monodisperse systems, with ad hoc modifications to account for polydispersity. In previous work it was shown that for bidisperse systems with moderate diameter ratios of 1：2 to 1：4, this approach leads to discrepancies, and a correction factor is needed. In this work we demonstrate that this correction factor also holds for more extreme diameter ratios of 1：5, 1：7 and 1： 10, although the force on the large particles is slightly overestimated when using the correction factor. The main origin of the correction is that the void surrounding the large particles becomes less in case ofa bidisperse mixture, as compared to a monodisperse system with the same volume fraction. We further investigated this discrepancy by calculating the volume per particle by means of Voronoi tessellation.

关键词： Bidisperse Fluid-particle interaction force Lattice Boltzmann simulation Direct numerical simulation

Impact of dams on flood occurrence of selected rivers in the United States

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Frontiers of Earth Science 2017年第2期11卷 268-282页

作者： Xuefei mEI P.H.A.j.m. van GELDER Zhijun DAI Zhenghong TANG State Key Laboratory of Estuarine & Coastal Research East China Normal University Shanghai 200062 China Faculty of Technology Policy and Management Delft University of Technology 2628BX Delft the Netherlands Community and Regional Planning Program University of Nebraska-Lincoln Lincoln NE 68588-0105 USA

A significant large number of dams have been constructed in the past two centuries in the United States. These dams＇ ability to regulate downstream flooding has received world-wide attention. In this study, data from 38 rivers distributed over the entire conterminous Untied States with extensive pre- and post-dam annual peak discharge records, were collected to research the impacts of various dams on the flood behaviors at a national scale. The results indicate that dams have led to significant reductions in flood magnitude for nearly all of the sites; the decrease rate in the mean of annual peak discharge varies between 7.4% and 95.14%, except for the Dead River, which increased by 1.46%. Because of dams＇ effective- ness, the probability density curve of annual peak flow changes from a flat to peaked shape because both the range and magnitude of high discharges are decreased. more- over, the potential impact of dams on flood characteristics were closely related to the dam＇s geographic location and function, the ratio of the storage capacity of the dam to the mean annual runoff of the river （C/R）, and the ratio of reservoir storage capacity to the area of its drainage （C/D）. Specifically, the effects of dams on annual peak flows were more related to latitude than longitude. Compared with dams built for other purposes, the dam exclusively used for flood management cut off more flood peaks. Increases in the ratios of C/R and C/D increased the degree of modification of annual maximum discharge.

关键词： flood characteristics river discharge dam,flood modification

Use of incipient motion data for backward erosion piping models

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International journal of Sediment Research 2019年第5期34卷 401-408页

作者： Vera m.van Beek Bryant A.Robbins Gijs j.C.m.Hoffmans Adam Bezuijen Leo C.van Rijn Deltares U.S.Army Engineer Research and Development Center Ghent University Leovanrijn-Sediment-Consultancy

Backward erosion piping involves the gradual removal of granular material under the action of water flow from the foundation of a dam or levee, whereby shallow pipes are formed that grow in the direction opposite to the flow. This pipe-forming process can ultimately lead to failure of a water-retaining structure and is considered one of the most important failure mechanisms for dikes and levees in the Netherlands and the United States. modeling of this mechanism requires the assessment of hydraulic conditions in the pipe, which are controlled by the particle equilibrium at the pipe wall. Since the pipe’s dimensions are controlled by the inflow to the pipe from the porous medium, the flow through the pipe is thought to be laminar for fine-to medium-grained sands. The literature provides data for incipient motion in laminar flow, which is reviewed here and complemented with data from backward erosion experiments. The experiments illustrate the applicability of the laminar incipient motion data to determine the erosion pipe dimensions and corresponding pipe hydraulics for fine-to medium-grained sands, for the purpose of backward erosion piping modeling.

关键词： Internal erosion Backward erosion piping Cylindrical test Incipient motion Dikes Levees

Differences in sensitivity of native and exotic fish species to changes in river temperature

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Current Zoology 2011年第6期57卷 852-862页

作者： R.S.E.W. LEUVEN A.j. HENDRIKS m.A.j. HUIjBREGTS H.j.R. LENDERS j. mATTHEWS van DER VELDE Radboud University Nijmegen Institute for Water and Wetland Research Department of Environmental Science Heyendaal- seweg 135 NL-6525 AJ Nijmegen The Netherlands Radboud University Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands Netherlands Centre for Biodiversity Naturalis P.O. Box 9517 NL-2300 RA Leiden The Netherlands

This paper describes the effects that temperature changes in the Rhine river distributaries have on native and exotic fish diversity. Site-specific potentially affected fractions （PAFs） of the regional fish species pool were derived using species sensitivity distributions （SSDs） for water temperature. The number of fish species in the river distributaries has changed remarkably over the last century. The number of native rheophilous species declined up until 1980 due to anthropogenic disturbances such as commercial fishing, fiver regulation, migration barriers, habitat deterioration and water pollution. In spite of progress in river re- habilitation, the native rheophilous fish fauna has only partially recovered thus far. The total number of species has strongly in- creased due to the appearance of more exotic species. After the opening of the Rhine-main-Danube waterway in 1992, many fish species originating from the Ponto-Caspian area colonized the Rhine basin. The yearly minimum and maximum river tempera- tures at Lobith have increased by circa 4 ~C over the period 1908-2010. Exotic species show lower PAFs than native species at both ends of the temperature range. The interspecific variation in the temperature tolerance of exotic fish species was found to be large. Using temporal trends in river temperature allowed past predictions of PAFs to demonstrate that the increase in maximum river temperature negatively affected a higher percentage of native fish species than exotic species. Our results support the hy- pothesis that alterations of the river Rhine＇s temperature regime caused by thermal pollution and global wanning limit the full recovery of native fish fauna and facilitate the establishment of exotic species which thereby increases competition between native and exotic species. Thermal refuges are important for the survival of native fish species under extreme summer or winter temperature conditions

关键词： Aquatic invaders Global warming Heat discharges Lethal temperature River Rhine Thermal heterogeneity

Postoperative surgical site infection in cholesteatoma surgery with and without mastoid obliteration, what can we learn?

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journal of Otology 2022年第1期17卷 25-30页

作者： F.L.j.Cals H.F.E.van der Toom R.m.metselaar A.van Linge m.P.van der Schroeff R.j.Pauw Department of Otorhinolaryngology and Head and Neck Surgery Erasmus Medical CenterRotterdamthe Netherlands

Introduction:This study aims to describe the occurrence of postoperative complications related to cholesteatoma surgery and to determine factors influencing the most common complication,*** surgical site infection(SSI)in cases with and without mastoid *** and methods:Retrospective analyses were performed on surgically treated cholesteatomas in our hospital between 2013 and *** characteristics,peri-and postoperative management and complications were *** cases were divided into two groups based on whether mastoid obliteration was performed or ***:A total of 336 cholesteatoma operations were performed,of which 248 cases received mastoid *** total 21 complications were observed,of which SSI was the most common(15/21).No difference in occurrence of any postoperative complication was seen between the obliteration and noobliteration group(p=0.798),especially not in the number of SSI(p=0.520).Perioperative and/or postoperative prophylactic antibiotics were not associated to the development of an SSI in both *** the no-obliteration group a younger age(p=0.015),as well as primary surgery(p=0.022)increased the risk for *** the obliteration group the use of bioactive glass(BAG)S53P4 was identified as independent predictor of SSI(p=0.008,OR 5.940).Discussion:SSI is the most common postoperative complication in cholesteatoma *** causes of SSI are multifactorial,therefore further prospective research is needed to answer which factors can prevent the development of an SSI in cholesteatoma surgery.

关键词： Cholesteatoma mastoid obliteration Postoperative surgical site infection Complications Bioactive glass S53P4

Swiss pumped hydro storage potential for Germany’s electricity system under high penetration of intermittent renewable energy

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journal of modern Power Systems and Clean Energy 2016年第4期4卷 542-553页

作者： Aagje j.H.van mEERWIjK Reném.j.BENDERS Alejandro DAVILA-mARTINEZ Gideon A.H.LAUGS IVEm(ESRIG) University of GroningenGroningenThe Netherlands

In order to cut greenhouse-gas emissions and increase energy security,the European Commission stimulates the deployment of intermittent renewable energy sources(IRES) towards *** an electricity system with high shares of IRES implemented in the network,energy balancing like storage is needed to secure grid stability and smooth demand *** hydro storage(PHS) is at this moment the best option for large scale *** has strong ambitions to further develop their PHS sector and become the battery of *** this research,the potential of the Swiss PSH plants is explored,whilst taking inflow into the upper reservoirs of the PHS plants into *** simulate electricity imbalance,Germany is used as a case *** already has a high penetration of IRES and has plans to increase installed IRES *** using an energy planning model(Power Plan),three future scenarios of the German electricity system were designed,each with a different set of IRES installed(solar,mixed and wind).Results show that the Swiss battery ambition offers most benefits to a wind-oriented scenario,reducing both shortages as well as *** inflow in Swiss PHS-reservoirs is of minor importance when looking at security of supply,although it was shown that the solarscenario profits more from inflow in terms of system ***,a potential conflict was observed in the solar-scenario between the need for electricity storage and the storage of natural inflow,resulting in more surpluses in the system when inflow was taken into account.

关键词： Pumped hydro storage(PHS) Local hydrology Germany Switzerland Intermittent renewable energy sources(IRES) Scenarios

Dispersal of invasive species by drifting

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Current Zoology 2011年第6期57卷 818-827页

作者： m.C. van RIEL G. van DER VELDE A. BIj DE VAATE Radboud University Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Section Aquatic Animal Ecology Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands Team Freshwater Ecology DLO-Alterra P.O. Box 47 6700 AA Wageningen The Netherlands Netherlands Centre for Biodiversity Naturalis EO. Box 9517 2300 RA Leiden The Netherlands Waterfauna Hydrobiologisch Adviesbureau Oostrandpark 30 8212 AP Lelystad The Netherlands

Drifting can be an effective way for aquatic organisms to disperse and colonise new areas. Increasing connectivity between European large rivers facilitates invasion by drifting aquatic macroinvertebrates. The present study shows that high abundances of invasive species drift in the headstream of the river Rhine. Dikerogammarus villosus and Chelicorophium cur- vispinum represented up to 90% of the total of drifting macroinvertebrates. Drift activity shows seasonal and diel patterns. most species started drifting in spring and were most abundant in the water column during the summer period. Drift activity was very low during the winter period. Diel patterns were apparent; most species, including D. villosus, drifted during the night. Drifting macroinvertebrates colonised stony substrate directly from the water column. D. villosus generally colonised the substrate at night, while higher numbers of C. curvispinum colonised the substrate during the day. It is very likely that drifting functions as a disper- sal mechanism for crustacean invaders. Once waterways are connected, these species are no longer necessarily dependent on dispersal vectors other than drift for extending their distribution range

关键词： Amphipods Invaders Colonization Drift Daily rhythms Seasonal variation

Supplementing oat hulls to the diet of suckling piglets altered their intestinal tract and colonic microbiota development

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Animal Nutrition 2023年第1期12卷 284-296页

作者： Hubèrt m.j.van Hees Koen Chiers Leo A.den Hartog Theo A.T.G.van Kempen Dominiek maes Sam millet Geert P.j.janssens Department of Veterinary and Biosciences Ghent UniversityMerelbekeBelgium Trouw Nutrition Research and Development Amersfoortthe Netherlands Department of Pathology Ghent UniversityMerelbekeBelgium Animal Nutrition Wageningen University and ResearchWageningenthe Netherlands Department of Animal Science North Carolina State UniversityRaleighNCUSA Department of Reproduction Obstetrics and Herd HealthGhent UniversityMerelbekeBelgium ILVO(Flanders Research Institute for Agriculture Fisheries and Food)MelleBelgium

Current study evaluated the effect of a fine and coarsely ground insoluble dietary fibre source on the gastrointestinal development of suckling *** hulls(OH)were selected as a model feedstuff,rich in cellulose,lignin,and insoluble dietary *** experimental supplemental diets were formulated:a finely ground,low fibre and nutrient dense diet served as control(CON).For the 2 high fibre diets,15%heat-treated starch in CON was exchanged with OH,either finely(OH-f)or coarsely ground(OH-c).Litters of 10 primi-and multiparous sows(mean litter size 14.6±0.84)were *** a litter,experimental diets were allotted to triplets of 4 *** approximately 12 d of age,piglets’individual feed intakes were recorded 2 times per day when separated from their dam for 70 *** could suckle with their dam for the remainder of the *** d 24 and 25,from the total pool of 120 piglets,seven healthy well-eating piglets per treatment were selected for post-mortem evaluation,resulting in 14 replicates per *** of OH-c and OH-f did not impede clinical health and production performance of *** full stomach weights tended to be greater for OH-c compared to OH-f whereas CON was intermediate(P=0.083).Supplementing OH significantly increased ileal villus height and caecal dry matter concentration(Pment specifically increased full gastrointestinal tract weight and caecum contents weight compared to piglets fed CON and ***,OH-c reduced colonic crypt depth when compared to OH-f(P=0.018).In conclusion,supplementing OH to a diet for suckling piglets exerted subtle developmental effects on gastrointestinal morphology and colonic microbial *** effects were largely independent from the particle size of the OH.

关键词： Oat hull Insoluble fibre Gastrointestinal development Suckling piglet