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journal of Animal Science and Biotechnology 2017年第2期8卷 391-404页

作者： Sandra j.A.van Kuijk josé C.del Río jorge Rencoret Ana Gutiérrez Anton S.M.Sonnenberg johan j.p.baars Wouter H.Hendriks john W.Cone Animal Nutrition Group Wageningen UniversityDe Elst 16708 WD WageningenThe Netherlands Instituto de Recursos Naturales y Agrobiologica de Sevilla(IRNAS-CSIC) Avenida Reina Mercedes1042012 SevilleSpain plant Breeding Wageningen UniversityDroevendaalsesteeg 16708 PB WageningenThe Netherlands

Background： The present work investigated the influence of lignin content and composition in the fungal treatment of lignocellulosic biomass in order to improve rumen degradability. Wheat straw and wood chips,differing in lignin composition, were treated with Lentinula edodes for 0, 2, 4, 8 and 12 wk and the changes occurring during fungal degradation were analyzed using pyrolysis-gas chromatography-mass spectrometry and detergent fiber ***： L. edodes preferentially degraded lignin, with only limited cellulose degradation, in wheat straw and wood chips, leaving a substrate enriched in cellulose. Syringyl（S）-lignin units were preferentially degraded than guaiacyl（G）-lignin units, resulting in a decreased S/G ratio. A decreasing S/G ratio（wheat straw： r =-0.72, wood chips： r =-0.75） and selective lignin degradation（wheat straw： r =-0.69, wood chips： r =-0.88） were correlated with in vitro gas production（IVGp）, a good indicator for rumen ***： L. edodes treatment increased the IVGp of wheat straw and wood chips. Effects on IVGp were similar for wheat straw and wood chips indicating that lignin content and 3D-structure of cell walls influence in vitro rumen degradability more than lignin composition.

关键词： Fungal treatment In vitro rumen degradability Lignocellulosic biomass py-GC/MS

The effect of particle size and amount of inoculum on fungal treatment of wheat straw and wood chips

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journal of Animal Science and Biotechnology 2017年第1期8卷 217-225页

作者： Sandra j. A. van Kuijk Anton S. M. Sonnenberg johan j. p. baars Wouter H. Hendriks john W. Cone Animal Nutrition Group Wageningen University De Elst 1 6708WD Wageningen The Netherlands plant Breeding Wageningen University Droevendaalsesteeg 1 6708PB Wageningen The Netherlands

Background： The aim of this study was to optimize the fungal treatment of lignocellulosic biomass by stimulating the colonization. Wheat straw and wood chips were treated with Ceriporiopsis subvermispora and Lentinula edodes with various amounts of colonized millet grains（0.5, 1.5 or 3.0 % per g of wet weight of substrate） added to the substrates. Also, wheat straw and wood chips were chopped to either 0.5 or 2 *** of the fungal treatment after 0, 2, 4, 6, or 8 wk of incubation was determined by changes in chemical composition, in vitro gas production（IVGp） as a measure for rumen degradability, and ergosterol content as a measure of fungal ***： Incomplete colonization was observed for C. subvermispora treated wheat straw and L. edodes treated wood chips. The different particle sizes and amounts of inoculum tested, had no significant effects on the chemical composition and the IVGp of C. subvermispora treated wood chips. particle size did influence *** treatment of wheat straw. The L. edodes treatment of 2 cm wheat straw resulted in a more selective delignification and a higher IVGp than the smaller particles. Addition of 1.5 % or 3 % L. edodes inoculum to wheat straw resulted in more selective delignification and a higher IVGp than addition of 0.5 % ***： particle size and amount of inoculum did not have an effect on C. subvermispora treatment of wood chips. At least 1.5 % L. edodes colonized millet grains should be added to 2 cm wheat straw to result in an increased IVGp and acid detergent lignin（ADL） degradation.

关键词： Amount of inoculum Fungal treatment In vitro rumen degradability Lignin degradation Lignocellulosic biomass particle size

Effects of local vegetation and plantation age for the parasitoid Asecodes mento- a biocontrol agent in organic strawberry fields

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Insect Science 2012年第5期19卷 604-608页

作者： johan A. Stenberg Department of Ecology Swedish University of Agricultural Sciences Uppsala Sweden

The parasitoid Asecodes mento （Walker, 1839）（Hymenoptera： Eulophidae） is the most important biocontrol agent of the strawberry leaf beetle Galerucella tenella （L.）（Coleoptera： Chrysomelidae） in northern Europe. Here, I investigated whether natural parasitism in organic strawberry plantations was affected by the presence of the alternative host plant meadowsweet （Filipendula ulmaria）, and whether parasitism rates differed between plantations of different ages （6 to 79 years）. I also investigated whether parasitoid brood size, body size and sex ratio differed between the two host plants in the field. parasitism was very low （0%） in newly established plantations and increased to a plateau （~40%） in fields where strawberries had been grown for approximately 20 years or longer. Such an extended colonization process is unacceptable for commercial growers. It would thus be desirable to find a method to catalyze parasitoid population buildup in young plantations. parasitoid brood sizes were larger in beetles collected from meadowsweet, while body size and sex ratio did not differ between parasitoids collected from the two plants. These findings suggest that meadowsweet can export parasitoids to neighboring strawberry fields. Although this is a possibility, I did not find any significant differences in parasitism rates between isolated strawberry fields and fields adjacent to meadowsweet stands, indicating that effects of local vegetation are small on parasitism rates. Releasing parasitoids in newly established strawberry plantations may be a better strategy for quickly obtaining high parasitism than intercropping with meadowsweet.

关键词： Asecodes mento biocontrol biological control Fragaria x ananassa,Galerucella tenella landscape ecology

Maximizing recovery time between knock-out races improves sprint cross-country skiing performance

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journal of Sport and Health Science 2022年第1期11卷 21-29页

作者： Kerry McGawley Coline Van Waerbeke Karl-johan Westberg Erik p.Andersson Swedish Winter Sports Research Centre Department of Health SciencesMid Sweden UniversityOstersund 83125Sweden

Background:In a sprint cross-country(XC)ski competition,the difference in recovery times separating the first and the second semi-final(SF)heats from the final(F)may affect *** aim of the current study was to compare the effects of longer *** recovery periods prescribed between the 3 knock-out races of a simulated sprint XC ski competition involving a prologue(p),quarter-final(QF),SF,and ***:Eleven well-trained XC ski athletes completed 2 simulated sprint XC ski competitions on a treadmill involving 4×883-m roller-ski bouts at a 4°incline using the gear 3 ski-skating *** first 3 bouts were completed at a fixed speed(pFIX,QFFIX,and SFFIX)corresponding to~96%of each individual’s previously determined maximal *** final bout was performed as a self-paced sprint time trial(FSTT).Test conditions differed by the time durations prescribed between the QFFIX,SFFIX,and FSTT,which simulated real-world XC ski competition conditions using maximum(MAX-REC)or minimum(MIN-REC)recovery ***:The FSTT was completed 5.4±5.5 s faster(p=0.009)during MAX-REC(179.2±18.1 s)compared to MIN-REC(184.6±20.0 s),and this was linked to a significantly higher power output(p=0.010)and total metabolic rate(p=0.009).The pre FSTT blood lactate(BLa)concentration was significantly lower during MAX-REC compared to MIN-REC(2.5±0.8 mmol/L vs.3.6±1.6 mmol/L,respectively;p=0.027),and the pre-to-post FSTT increase in BLa was greater(8.8±2.1 mmol/L vs.7.1±2.3 mmol/L,respectively;p=0.024).No other differences for MAX-REC ***-REC reached significance(p>0.05).Conclusion:performance in a group of well-trained XC skiers is negatively affected when recovery times between sprint heats are minimized which,in competition conditions,would occur when selecting the last QF *** result is combined with a higher pre-race BLa concentration and a reduced rise in BLa concentration under shorter recovery *** findings may help inform decision making when

关键词： Energetics Repeated sprints Roller skiing Simulated competition Tactics

Exhuming the Meso-Cenozoic Kyrgyz Tianshan and Siberian Altai-Sayan:A review based on low-temperature thermochronology

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Geoscience Frontiers 2016年第2期7卷 155-170页

作者： Stijn Glorie johan De Grave Centre for Tectonics Resources and Exploration(TRaX)Department of Earth SciencesSchool of Physical SciencesThe University of Adelaide Dept.Geology & Soil Science MINPET GroupGhent University

Thermochronological datasets for the Kyrgyz Tianshan and Siberian Altai-Sayan within Central Asia reveal a punctuated exhumation history during the Meso-Cenozoic. In this paper, the datasets for both regions are collectively reviewed in order to speculate on the links between the Meso-Cenozoic exhumation of the continental Eurasian interior and the prevailing tectonic processes at the plate margins. Whereas most of the thermochronological data across both regions document late jurassic -Cretaceous regional basement cooling, older landscape relics and dissecting fault zones throughout both regions preserve Triassic and Cenozoic events of rapid cooling, respectively. Triassic cooling is thought to reflect the Qiangtang-Eurasia collision and/or rifting/subsidence in the West Siberian basin. Alternatively, this cooling signal could be related with the terminal terrane-amalgamation of the Central Asian Orogenic Belt. For the Kygyz Tianshan, late jurassic-Cretaceous regional exhumation and Cenozoic fault reactivations can be linked with specific tectonic events during the closure of the palaeo-Tethys and Neo-Tethys Oceans, respectively. The effect of the progressive consumption of these oceans and the associated collisions of Cimmeria and India with Eurasia probably only had a minor effect on the exhumation of the Siberian Altai-Sayan. More likely, tectonic forces from the east （present-day co- ordinates） as a result of the building and collapse of the Mongol-Okhotsk orogen and rifting in the Baikal region shaped the current Siberian Altai-Sayan topography. Although many of these hypothesised links need to be tested further, they allow a first-order insight into the dynamic response and the stress propagation pathways from the Eurasian margin into the continental interior.

关键词： Central Asia Tianshan Altai Sayan Thermochronology Exhumation Fault reactivation

环境因子对双孢蘑菇损伤敏感性的影响（英文）

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菌物学报 2016年第11期35卷 1375-1386页

作者：高巍 baars johan jp DOLSTRA Oene VISSER Richard GF 张金霞 SONNENBERG Anton SM plant Breeding Wageningen University and Research Center 中国农业科学院农业资源与农业区划研究所北京100081

在机械损伤过程中,白色双孢蘑菇极易被损伤并迅速褐变,使得机械采收的鲜菇质量低下,并且影响机械采收技术的应用和发展。机械采收双孢蘑菇的褐变程度(损伤敏感性)受栽培环境条件的影响。本文应用因子设计分析的方式研究多个因子对双孢... 详细信息

在机械损伤过程中,白色双孢蘑菇极易被损伤并迅速褐变,使得机械采收的鲜菇质量低下,并且影响机械采收技术的应用和发展。机械采收双孢蘑菇的褐变程度(损伤敏感性)受栽培环境条件的影响。本文应用因子设计分析的方式研究多个因子对双孢蘑菇机械损伤敏感性的影响。以4个菌株为材料测试3个环境因子对双孢蘑菇损伤敏感性的影响,即覆土的厚度(分为2.5cm和5cm两个水平),覆土的湿度(分为干覆土和正常覆土两个水平),以及菇房内的相对湿度(分为80%和87%两个水平)。目的是找出能够在不敏感菌株和敏感菌株间产生最大敏感性差异的环境条件,由此得到的环境条件将应用到后续的群体分离分析中以得到最大的敏感性变异率。根据方差分析结果得出基因型(菌株)和覆土厚度是影响损伤敏感性的显著性因子,因子间相互作用显著。能够在不敏感菌株和敏感菌株间产生最大的损伤敏感性差异的环境条件为正常湿度的5cm厚覆土材料和87%的菇房内相对湿度。

关键词：双孢蘑菇损伤敏感性环境因子空气相对湿度覆土含水量覆土厚度

An experimental study of elastic properties of dragonfly-like flapping wings for use in biomimetic micro air vehicles(BMAVs)

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Chinese journal of Aeronautics 2017年第2期30卷 726-737页

作者： praveena Nair Sivasankaran Thomas Arthur Ward Erfan Salami Rubentheren Viyapuri Christopher j.Fearday Mohd Rafie johan Department of Mechanical Engineering University of Malaya KuaIa Lumpur 50603 Malaysia School of Engineering and physical Sciences Heriot-Watt University Malaysia Putrajaya 62200 Malaysia Department of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia

This article studies the elastic properties of several biomimetic micro air vehicle（BMAV）wings that are based on a dragonfly *** are a new class of unmanned micro-sized air vehicles that mimic the flapping wing motion of flying biological organisms（e.g.,insects,birds,and bats）.Three structurally identical wings were fabricated using different materials：acrylonitrile butadiene styrene（ABS）,polylactic acid（pLA）,and *** wing frame structures were fabricated from these materials and then a nanocomposite film was adhered to them which mimics the membrane of an actual *** wings were then attached to an electromagnetic actuator and passively flapped at frequencies of 10-250 Hz.A three-dimensional high frame rate imaging system was used to capture the flapping motions of these wings at a resolution of 320 pixels x 240 pixels and 35000 frames per *** maximum bending angle,maximum wing tip deflection,maximum wing tip twist angle,and wing tip twist speed of each wing were measured and compared to each other and the actual dragonfly *** results show that the ABS wing has considerable flexibility in the chordwise direction,whereas the pLA and acrylic wings show better conformity to an actual dragonfly wing in the spanwise *** studies have shown that the aerodynamic performance of a BMAV flapping wing is enhanced if its chordwise flexibility is increased and its spanwise flexibility is ***,the ABS wing（fabricated using a 3D printer） shows the most promising results for future applications.

关键词： ABS Acrylic Biomimetic micro air vehicle Flapping mechanism pLA Wing structure

Rock mass response for lined rock caverns subjected to high internal gas pressure

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journal of Rock Mechanics and Geotechnical Engineering 2023年第1期15卷 119-129页

作者： Davi Rodrigues Damasceno johan Spross Fredrik johansson Division of Soil and Rock Mechanics KTH Royal Institute of TechnologySE-10044StockholmSweden

The storage of hydrogen gas in underground lined rock caverns(LRCs)enables the implementation of the first fossil-free steelmaking process to meet the large demand for crude *** the response of rock mass is important to ensure that gas leakage due to rupture of the steel lining does not *** and numerical models can be used to estimate the rock mass response to high internal pressure;however,the fitness of these models under different in situ stress conditions and cavern shapes has not been *** this paper,the suitability of analytical and numerical models to estimate the maximum cavern wall tangential strain under high internal pressure is *** analytical model is derived in detail and finite element(FE)models considering both two-dimensional(2D)and three-dimensional(3D)geometries are *** models are verified with field measurements from the LRC in Skallen,southwestern *** analytical model is inexpensive to implement and gives good results for isotropic in situ stress conditions and large cavern *** the case of anisotropic horizontal in situ stresses,as the conditions in Skallen,the 3D FE model is the best approach.

关键词： Lined rock caverns(LRCs) High pressure Rock mass response In situ stress condition Cavern shape Gas storage

Supplemental Smartamine M in higher-energy diets during the prepartal period improves hepatic biomarkers of health and oxidative status in Holstein cows

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journal of Animal Science and Biotechnology 2017年第3期8卷 624-635页

作者： Mario Vailati-Riboni johan S.Osorio Erminio Trevisi Daniel Luchini juan j.Loor Mammalian Nutri physio Genomics Department of Animal Sciences and Division of Nutritional SciencesUniversity of IllinoisUrbanaIL 61801USA Istituto di Zootecnica Facolt àdi Scienze Agrarie Alimentari e AmbientaliUniversità Cattolica del Sacro Cuore29122 PiacenzaItaly Adisseo NA AlpharettaGA 30022USA. Dairy and Food Science Department South Dakota State University1111 College Ave113H Alfred DairyScience HallBrookings SD 57007USA

Background： Feeding higher-energy prepartum is a common practice in the dairy industry. However, recent data underscore how it could reduce performance, deepen negative energy balance, and augment inflammation and oxidative stress in fresh cows. We tested the effectiveness of rumen-protected methionine in preventing the negative effect of feeding a higher-energy prepartum. Multiparous Holstein cows were fed a control lower-energy diet（CON, 1.24 Mcal/kg DM; high-straw） during the whole dry period（-50 d）, or were switched to a higher-energy（OVE, 1.54 Mcal/kg DM）, or OVE plus Smartamine M（OVE ＋ SM; Adisseo NA） during the last 21 d before *** cows received the same lactation diet（1.75 Mcal/kg DM）. Smartamine M was top-dressed on the OVE diet（0.07% of DM） from -21 through 30 d in milk（DIM）. Liver samples were obtained via percutaneous biopsy at -10, 7 and 21 DIM. Expression of genes associated with energy and lipid metabolism, hepatokines, methionine cycle, antioxidant capacity and inflammation was ***： postpartal dry matter intake, milk yield, and energy-corrected milk were higher in CON and OVE ＋ SM compared with OVE. Furthermore, milk protein and fat percentages were greater in OVE ＋ SM compared with CON and OVE. Expression of the gluconeogenic gene pCK1 and the lipid-metabolism transcription regulator ppARA was again greater with CON and OVE ＋ SM compared with OVE. Expression of the lipoprotein synthesis enzyme MTTp was lower in OVE ＋ SM than CON or OVE. Similarly, the hepatokine FGF21, which correlates with severity of negative energy balance, was increased postpartum only in OVE compared to the other two groups. These results indicate greater liver metabolism and functions to support a greater production in OVE ＋ SM. At 7 DIM, the enzyme GSR involved in the synthesis of glutathione tended to be upregulated in OVE than CON-fed cows, suggesting a greater antioxidant demand in overfed cows. Feeding OVE ＋ SM resulted in lower similar express

关键词： Energy Methionine Nutrigenomics Transition period

Long-term experimental study on gravitational sedimentation of water aluminum oxide nanofluid at different volumetric concentrations

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International journal of Sediment Research 2023年第3期38卷 303-315页

作者： Mario Misale johan Augusto Bocanegra Annalisa Marchitto DIME-Department of Mechanics Energetics Management and Transportation Thermal Engineering and Environmental Conditioning Division University of Genoa

The stability of nanofluids is critical in engineering applications. The sedimentation of the nanoparticles in the base fluid limits the stability of the nanofluid. By measuring the absorbance of a visible laser through water aluminum oxide nanofluids it is possible to observe the evolution of the sedimentation process. A simple experimental setup consisting of a thin closed test cavity（0.8 mm or 1.5 mm thickness）filled with nanofluid and a set of laser diodes-photodiodes pairs was used in the experiments to determine the absorbance and the local volumetric concentration. The evolution of the local volumetric concentration of the nanofluid was measured at 13 height positions along the test cavity. Five initial volumetric concentrations of aluminum oxide（Al2O3; 0.5%, 1.0%, 1.5%, 2.0%, 3.0% and 4.0%） were considered. Data and digital photos were acquired for a total time lapse of 260 days. The results were independent of the container thickness. The same general trend was consistent for all the initial volumetric concentrations, i.e., the sedimentation rate decreases in time. The time evolution of the volumetric concentration was compared with results from a modified Mason-Weaver model. The comparison was possible by setting a variable sedimentation velocity in the model, suggesting that the sedimentation is affected by the dynamics of nanoparticle clusters with diverse sizes produced by agglomeration.

关键词： pure nanofluid Aluminum oxide Nanoscale alumina particles Colloid sedimentation Nanoparticle settling Mason-Weaver model