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国外畜牧学（猪与禽） 2024年第1期44卷 12-13页

作者： Katia Pedrosa Kathrin Buehler Jan Dirk van der Klis 张相鑫(译) 王晶晶(校) 孟祥光(制图) 不详

维生素D是一种重要的营养物质,母猪在妊娠后期和哺乳期对其需要量非常高。本文概述了维生素D对母猪分娩的影响,提出可以在常规添加维生素D之外补充1,25-二羟基维生素D3糖苷,以缩短分娩时间,减少分娩过程中的人为干预,减少死胎数。

关键词：维生素D 1 25-二羟基维生素D3糖苷分娩

No evidence for a genetic association between female mating preference and male secondary sexual trait in a Lake Victoria cichlid fish

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Current Zoology 2010年第1期56卷 57-64页

作者： Inke van der SLUIJS Ole SeeHAUSeN Tom J.m.van DOOReN Jacques J.m.van ALPHeN Department of Animal ecology Institute of Biology Leiden University Department of Biology McGill University Institute of ecology and evolution University of Bern Department of Fish ecology & evolution Centre of Ecology Eawag Swiss Federal Institute for Aquatic Science and TechnologyEvolution & Biogeochemistry

Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in the rapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or accelerated by genetic associations between female preference loci and male coloration loci. Preferences, as well as coloration, are heritable traits and are probably determined by more than one gene. However, little is known about potential genetic associations between these traits. In turbid water, we found a population that is variable in male nuptial coloration from blue to yellow to red. males at the extreme ends of the phenotype distribution resemble a reproductively isolated species pair in clear water that has diverged into one species with blue-grey males and one species with bright red males. Females of the turbid water population vary in mating preference coinciding with the male phenotype distribution. For the current study, these females were mated to blue males. We measured the coloration of the sires and male offspring. Parents-offspring regression showed that the sires did not affect male offspring coloration, which confirms earlier findings that the blue species breeds true. In contrast, male offspring coloration was determined by the identity of the dams, which suggests that there is heritable variation in male color genes between females. However, we found that mating preferences of the dams were not correlated with male offspring coloration. Thus, there is no evidence for strong genetic linkage between mating preference and the preferred trait in this population [Current Zoology 56 （1）： 57-64 2010].

关键词： Speciation Sexual selection mate choice Genetic association Cichlid fish Lake Victoria

Toward more reliable stability measurements in stance: recommendations for number of measurements, foot position and feedback——a cross-sectional study among servicemen

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military medical Research 2020年第2期7卷 199-208页

作者： Saskia maria Theresia van der Heijden maarten Reinders Prins Peter van der Wurff Physical Therapy Sciences Program in Clinical Health SciencesUniversity Medical Center Utrecht3584CX UtrechtThe Netherlands Research and Development Military Rehabilitation Center AardenburgKorte Molenweg 33941PW DoomThe Netherlands Department of Human movement Sciences Faculty of Behavioural and Movement SciencesVrije Universiteit Amsterdam and Amsterdam Movement Sciences1081BT AmsterdamThe Netherlands Institute for Human movement Studies HU University of Applied Sciences Utrecht3584CS UtrechtThe Netherlands

Background:In the military,insufficient postural stability is a risk factor for developing lower extremity *** stability training programs are effective in preventing these ***,an objective method for the measurement of postural stability in servicemen is *** primary objective of this study was to assess the influence of the number of repetitions,different foot positions and real-time visual feedback on postural stability,as well as their effects on the intrasession reliability of postural stability measurements in *** secondary objective was to assess the concurrent validity of the ***:Twenty healthy servicemen between 20 and 50 years of age and in active duty were eligible for this quantitative,cross-sectional *** measurements took place on a force plate,measuring the mean velocity of the center of *** participants were asked to stand as still as possible in three different foot positions(wide stance,small stance,and on one leg),five times each for 45 s each time,and the measurements were performed with and without real-time visual ***:We observed a significant main effect of foot position(Peedback(P=0.119)or repetition number(P=0.915).Postural stability decreased in the more challenging foot *** ICC estimates varied from 0.809(one repetition in wide stance)to 0.985(five repetitions on one leg).The common variance(R2)between different foot positions without feedback varied between 0.008(wide stance)and ***:To yield reliable data,wide-stance measurements should be conducted three times,and small-stance measurements and measurements on one leg should be conducted two *** scores of a measurement in a particular foot position cannot predict the scores of measurements in other foot positions.

关键词： Postural stability Center of Pressure Servicemen Intrasession reliability Concurrent validity

Tapping the tree-ring archive for studying effects of resin extraction on the growth and climate sensitivity of Scots pine

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Forest ecosystems 2017年第3期4卷 167-173页

作者： ernst van der maaten Annemarie mehl martin Wilmking marieke van der maaten-Theunissen Institute of Botany and Landscape ecology University of Greifswald

Background： In the German Democratic Republic（GDR）, resin tapping in Scots pine（Pinus sylvestris L.） forests was a major economic activity, and resin-tapped stands are frequently found up until this day. In this study, we investigate how the mechanical damage caused by resin tapping affects the growth and climate sensitivity of Scots pine using a dendroecological ***： Tree-ring samples were collected from resin-tapped and non-tapped trees in two forest areas in northeastern Germany, and tree-growth patterns were analyzed. For elucidating effects of resin tapping on the climate sensitivity of pine growth, climate-growth relationships and pointer years were ***： We observed that resin tapping positively affects tree growth at breast height, likely as wood formation is concentrated on the living part of the bole（i.e. after tapping there is no growth taking place on the tapping face due to the mechanical damage done to the cambium）. We observed no differences in the climate sensitivity of tapped and non-tapped trees, nor in the occurrence of extreme growth ***： Our results highlight that resin extraction is, apart from inflicting mechanical damage, not altering the sensitivity of Scots pine growth to climatic conditions.

关键词： Climate-growth relationships Dendroecology mechanical damage

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

Cost projections for microwave plasma CO production using renewable energy

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Journal of energy Chemistry 2022年第8期31卷 507-513,I0014页

作者： Remko J.Detz Bob van der Zwaan Netherlands Organisation for Applied Scientific Research(TNO) Amsterdam 1043 NTThe Netherlands Faculty of Science(HImS and IAS) University of AmsterdamAmsterdam 1090 GDThe Netherlands School of Advanced International Studies(SAIS) Johns Hopkins UniversityBologna 40126Italy

Successful deployment of renewable fuel production requires substantial cost reduction along the entire value chain of the underlying manufacturing *** improve their performance,renewable fuel production technologies should follow a cost-reducing learning *** this article,we adopt recent evidence that learning-by-doing is directly influenced by the technology unit size and explore three scenarios for microwave plasma CO_(2)conversion in which the learning rate varies between 10%,15%,and 20%.Our projections reveal that the total investments required to deploy this CO_(2)conversion technology at an exajoule scale decline from 83 down to 23 billion euros under a 10%increase in the value of the learning *** CO_(2) production costs in 2050 amount to 247–346€(2019)/t CO_(2),in which the range is determined by the value of the learning *** under substantial learning until 2050 the levelized CO production cost is unlikely to become competitive with conventional natural gas-based CO_(2) production processes,except when a CO_(2)tax is applied of up to 150€(2019)/t CO_(2).To optimally exploit effects of learning-by-doing,we recommend developing several CO production technologies simultaneously with multiple unit sizes,so as to improve the chance of ultimately selecting the process with the highest learning rate.

关键词： CO_(2)utilization Synthetic fuels Renewable chemicals Learning curves Unit size

microstructure and dislocation structure evolution during creep life of Ni-based single crystal superalloys

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Journal of materials Science & Technology 2020年第10期42卷 207-214页

作者： Hao Yu Wei Xu Sybrand van der Zwaag Novel Aerospace materials Group Faculty of Aerospace EngineeringDelft University of Technology2629HSDelftthe Netherlands State Key Laboratory of Rolling and Automation Northeastern University110819ShenyangChina

The high performance of Ni single crystal superalloys during high temperature low stress creep service,is intrinsically determined by the combined effects of microstructural evolution and the dislocation *** the field of the evolution of dislocation network,two main recovery mechanism based on dislocation migration dominate the *** is superdislocations shearing intoγ’rafts through a two-superpartials-assisted *** is the compact dislocations migrating alongγ/γ’*** two mechanisms are similarly climb-rate-controlled *** this work,a model for the minimum creep rate based on thermodynamic and kinetic calculations and using an existing detailed dislocation dynamics model has been built by taking the dislocation migration behaviours as well as the rafted microstructure into consideration,which can well reproduce the([100]tensile)creep properties of existing Ni superalloy grades,without the need to make the dislocation parameter values composition dependent.

关键词： Ni superalloys microstructure evolution Dislocation behaviour

An unusual cause of hematemesis:Goiter

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World Journal of Gastroenterology 2006年第33期12卷 5412-5415页

作者： Astrid Am van der Veldt mohammed Hadithi marinus A Paul Fred G van den Berg Chris JJ mul-der mikael e Craanen Department of Gastroenterology VU University Medical Center Amsterdam The Netherlands Department of Surgery VU University Medical Center Amsterdam The Netherlands Department of Radiology VU University Medical Center Amsterdam The Netherlands

Downhill varices are located in the upper part of the esophagus and are usually related to superior vena cava obstruction. Bleeding from these varices is extremely rare. We describe a 77-year-old patient with hematemesis due to downhill varices as a result of recurrent goiter. A right lobe thyroidectomy was carried out with disappearance of the varices.

关键词： Downhill esophageal Varices Goiter Hematemesis

Rank one eisenstein cohomology of local systems on the moduli space of abelian varieties

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Science China mathematics 2011年第8期54卷 1621-1634页

作者： van der GeeR Gerard Korteweg-de Vries Instituut Universiteit van AmsterdamPostbus 942481090 GE AmsterdamThe Netherlands

We give a formula for the eisenstein cohomology of local systems on the partial compactification of the moduli of principally polarized abelian varieties given by rank 1 degenerations.

关键词： eisenstein cohomology BGG complex

Design of bidirectional frictional behaviour for tactile contact using ellipsoidal asperity micro-textures

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Friction 2022年第5期10卷 762-771页

作者： Dmitrii SeRGACHeV David mATTHeWS emile van der HeIDe Laboratory for Surface Technology and Tribology Faculty of Engineering TechnologyUniversity of TwenteOverissel 7522 LIWEnschedethe Netherlands Faculty of engineering and Architecture Ghent UniversitEast Flanders 9000GhenBelgium

Tactile perception and friction can be modified by producing a deterministic surface *** of surface feature arrangement and texture symmetry can produce an anisotropic frictional *** is generally achieved through skin hysteresis by promoting its *** work investigates whether a bidirectional friction can be created with microscale ellipsoidal asperity textures,thus relying on the adhesive component of *** this purpose,four textured samples with various asperity dimensions were moulded with a silicone rubber having an elastic modulus comparable to that of the *** of friction measurements were conducted in-vivo in two sliding directions with a range of normal loads up to 4 *** element method(Fem)was used to study elastic deformation effects,explain the observed friction difference,and predict surface material *** performed perpendicular to the asperity major radii showed consistently higher friction coefficients than that during parallel *** the larger asperity dimensions,a change of the sliding direction increased friction up to a factor of *** numerical analysis showed that this effect is mostly related to elastic asperity *** friction differences can be further controlled by asperity dimensions,spacing,and material properties.

关键词： surface texture sliding direction skin friction elastomer