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Influence of main dietary chemical constituents on the in vitro gas and methane production in diets for dairy cows

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Journal of Animal Science and Biotechnology 2017年第1期8卷 99-106页

作者： Laura Maccarana Mirko Cattani Franco Tagliapietra Lucia Bailoni stefano schiavon epartment of Comparative Biomedicine and Food Science (BCA) University of Padova Viale dell'Universita 16 35020 Legnaro (PD) Italy Department of Agronomy Food Natural resources Animals and Environment (DAFNAE) University of Padova Viale dell＇Universita 16 35020 Legnaro (PD) Italy

Background： Modification of chemical composition of diets fed to dairy cows might be a good strategy to reduce methane（CH4） production in the rumen. Notable reductions of CH4 production compared to conventional highroughages rations were more frequently observed for very concentrated diets or when fat supplements were used. In these cases, the reduction in the gas emission was mainly a consequence of an overall impairment of rumen function with a reduction of fiber digestibility. These strategies do not always comply with feeding standards used in intensive dairy farms and they are usually not applied owing to the risks of negative health and economic ***, the present study evaluated the effects of seven commercial diets with contents of neutral detergent fiber（NDF）,protein and lipids ranging 325 to 435 g/kg DM, 115 to 194 g/kg DM, and 26 to 61 g/kg DM, respectively, on in vitro degradability, gas（GP）, and CH4 ***： In this experiment, changes in the dietary content of NDF, crude protein（CP） and lipids were always obtained at the expense or in favor of starch. A decreased of the dietary NDF content increased NDF（NDFd） and true DM（TDMd） degradability, and increased CH4 production per g of incubated DM（P 〈 0.001）, but not that per g of TDMd. An increase of the dietary CP level did not change in vitro NDFd and TDMd, decreased GP per g of incubated DM（P 〈 0.001）, but CH4 production per g of TDMd was not affected. An increased dietary lipid content reduced NDFd, TDMd,and GP per g of incubated DM, but it had no consequence on CH4 production per g of ***： It was concluded that, under commercial conditions, changes in dietary composition would produce small or negligible alterations of CH4 production per unit of TDMd, but greater differences in GP and CH4 production would be expected when these amounts are expressed per unit of DM intake. The use of TDMd as a standardizing parameter is proposed to account for possible difference in D

关键词： Dairy cows Dietary manipulation Gas production In vitro techniques Methane production

Methodological factors affecting gas and methane production during in vitro rumen fermentation evaluated by meta-analysis approach

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Journal of Animal Science and Biotechnology 2017年第1期8卷 236-247页

作者： Laura Maccarana Mirko Cattani Franco Tagliapietra stefano schiavon Lucia Bailoni Roberto Mantovani Department of Comparative Biomedicine and Food Science (BCA) University of Padova Viale dell'Universita 16 35020 Legnaro (PD) Italy Department of Agronomy Food Natural resources Animals and Environment (DAFNAE) University of Padova Viale dell'Universita 16 35020 Legnaro (PD) Italy

Effects of some methodological factors on in vitro measures of gas production（GP, mL/g DM）, CH4production（mL/g DM） and proportion（% CH4 on total GP） were investigated by meta-analysis. These factors were considered：pressure in the GP equipment（0 = constant; 1 = increasing）, incubation time（0 = 24; 1 = ≥ 48 h）, time of rumen fluid collection（0 = before feeding; 1 = after feeding of donor animals）, donor species of rumen fluid（0 = sheep; 1 =bovine）, presence of N in the buffer solution（0 = presence; 1 = absence）, and ratio between amount of buffered rumen fluid and feed sample（BRF/FS; 0 = ≤ 130 mL/g DM; 1 = 130–140 mL/g DM; 2 = ≥ 140 mL/g DM）. The NDF content of feed sample incubated（NDF） was considered as a continuous variable. From an initial database of 105 papers, 58 were discarded because one of the above-mentioned factors was not stated. After discarding 17 papers,the final dataset comprised 30 papers（339 observations）. A preliminary mixed model analysis was carried out on experimental data considering the study as random factor. Variables adjusted for study effect were analyzed using a backward stepwise analysis including the above-mentioned variables. The analysis showed that the extension of incubation time and reduction of NDF increased GP and CH4 values. Values of GP and CH4 also increased when rumen fluid was collected after feeding compared to before feeding（＋26.4 and ＋9.0 mL/g DM, for GP and CH4）,from bovine compared to sheep（＋32.8 and ＋5.2 mL/g DM, for GP and CH4）, and when the buffer solution did not contain N（＋24.7 and ＋6.7 mL/g DM for GP and CH4）. The increase of BRF/FS ratio enhanced GP and CH4production（＋7.7 and ＋3.3 mL/g DM per each class of increase, respectively）. In vitro techniques for measuring GP and CH4 production are mostly used as screening methods, thus a full standardization of such techniques is not feasible. However, a greater harmonization of analytical procedures（i.e., a reduction in the number of available protocols） would be usefu

关键词： Experimental factors Gas production In vitro rumen fermentation Meta-analysis Methane production

Incoherent non-Hermitian skin effect in photonic quantum walks

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Light(Science & Applications) 2024年第5期13卷 885-893页

作者： stefano Longhi Dipartimento di Fisica Politecnico di MilanoPiazza L.da Vinci 32I-20133 MilanoItaly IFISC(UIB-CSIC) Instituto de Fisica Interdisciplinar y Sistemas ComplejosE-07122 Palma de MallorcaSpain

The non-Hermitian skin effect describes the concentration of an extensive number of eigenstates near the boundaries of certain dissipative *** phenomenon has raised a huge interest in different areas of physics,including photonics,deeply expanding our understanding of non-Hermitian systems and opening up new avenues in both fundamental and applied aspects of topological *** skin effect has been associated to a nontrivial pointgap spectral topology and has been experimentally demonstrated in a variety of synthetic matter systems,including photonic *** most of physical models exhibiting the non-Hermitian skin effect full or partial wave coherence is generally *** we push the concept of skin effect into the fully incoherent regime and show that rather generally(but not universally)the non-Hermitian skin effect persists under dephasing *** results are illustrated by considering incoherent light dynamics in non-Hermitian photonic quantum walks.

关键词： dynamics. quantum effect

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置换通风设计方法综述

置换通风设计方法综述

Dependence of impact regime boundaries on the initial temperatures of projectiles and targets

全国暖通空调制冷2006学术年会

作者： stefano schiavon 意大利Padova大学

置换通风系统应用于欧洲的高热负荷工业建筑已有30多年。近20年置换通风系统在北欧国家的非工业建筑中也逐渐流行起来,如写字楼、学校、剧院等。在房间中,垂直温度梯度导致了置换通风。由于地板处的空气温度要低于天花板处空气的温度,... 详细信息

置换通风系统应用于欧洲的高热负荷工业建筑已有30多年。近20年置换通风系统在北欧国家的非工业建筑中也逐渐流行起来,如写字楼、学校、剧院等。在房间中,垂直温度梯度导致了置换通风。由于地板处的空气温度要低于天花板处空气的温度,所以工作区和天花板之间的几度温差就使经过工作区的空气可以通过天花板处排走。置换通风的规律可以使能源有较高的利用率,因为置换通风的送风温度可以比混合通风的送风温度高,而且它可以节约能量(较

关键词：置换通风热舒适设计方法室内空气质量

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Defence Technology（防务技术） 2024年第1期31卷 49-57页

作者： stefano Signetti Andreas Heine Fraunhofer-Institut für Kurzzeitdynamik Ernst-Mach-InstitutEMIErnst-Zermelo-Str.479104 Freiburg im BreisgauGermany

Towards higher impact velocities,ballistic events are increasingly determined by the material *** effects might range from moderate thermal softening to full phase *** particular,it is of great interest to quantify the conditions for incipient or full melting of metals during impact interactions,which result in a transition from still strength-affected to hydrodynamic material *** this work,we investigate to which extent the respective melting thresholds are also dependent on the initial,and generally elevated,temperatures of projectiles and targets before *** is studied through the application of a model developed recently by the authors to characterize the transition regime between high-velocity and hypervelocity impact,for which the melting thresholds of materials were used as the defining *** obtained results are expected to be of general interest for ballistic application cases where projectiles or targets are *** conditions might result,for example,from aerodynamic forces acting onto a projectile during atmospheric flight,explosive shapedcharge-jet formation or armor exposure to environmental *** performed analyses also broaden the scientific understanding of the relevance of temperature in penetration events,generally known since the 1960s,but often not considered thoroughly in impact studies.

关键词： Ballistic impact Thermal effects Metallic targets Energy partitioning Homologous temperature

Physical exercise and traumatic brain injury: is it question of time?

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Neural Regeneration Research 2024年第3期19卷 475-476页

作者： Valentina Mastrorilli stefano Farioli Vecchioli Institute of Biochemistry and Cell Biology Institute of Biochemistry and Cell BiologyNational Research Council(IBBC/CNR)MonterotondoRomeItaly Plaisant S.R.L. RomeItaly

Is it better to be safe than sorry?This Hamletic dilemma has always stimulated medical-scientific debates in numerous fields of *** among these,the preventive-therapeutic approach to the treatment of brain trauma is one of the most striking *** brain injury(TBI)is a leading cause of brain damage among young and elderly populations with a very high hospitalization and death *** is characterized by two pathologically distinct but strictly consequential phases:a first characterized by an immediate and highly variable mechanical dysfunction of the brain tissue,which involves widespread cell death and tissue degeneration,followed by a second phase which can last from days to even years depending on the severity of the TBI and the patient’s pre-existing health *** processes,including inflammatory phenomena,oxidative stress associated with metabolic,vascular,and neuro-modulatory deficits,are very often responsible for neuro-motor and psychological deficits leading to long-term disabilities(Kaur and Sharma,2018).

关键词： injury striking modulator

Integrated CO_(2)capture and reduction catalysis:Role ofγ-Al_(2)O_(3)support,unique state of potassium and synergy with copper

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Journal of Environmental Sciences 2024年第6期140卷 113-122页

作者： Donato Pinto stefano Minorello Zhouping Zhou Atsushi Urakawa Catalysis Engineering Department of Chemical EngineeringDelft University of TechnologyDelft2629HZNetherlands

Carbon dioxide capture and reduction(CCR)process emerges as an efficient catalytic strategy for CO_(2)capture and conversion to valuable chemicals.K-promoted Cu/Al_(2)O_(3)catalysts exhibited promising CO_(2)capture efficiency and highly selective conversion to syngas(CO+H_(2)).The dynamic nature of the Cu-K system at reaction conditions complicates the identification of the catalytically active phase and surface *** present work aims at more precise understanding of the roles of the potassium and copper and the contribution of the metal oxide ***γ-Al_(2)O_(3)guarantees high dispersion and destabilisation of the potassium phase,potassium and copper act synergistically to remove CO_(2)from diluted streams and promote fast regeneration of the active phase for CO_(2)capture releasing CO while passing H_(2).A temperature of 350℃is found necessary to activate H_(2)dissociation and generate the active sites for CO_(2)*** effects of synthesis parameters on the CCR activity are also described by combination of ex-situ characterisation of the materials and catalytic testing.

关键词： Carbon dioxide Carbon capture and utilisation CO_(2)capture and reduction Solid CO_(2)sorbents Heterogeneous catalysis Potassium Copper catalysts Aluminium oxide

Estimating wood quality attributes from dense airborne LiDAR point clouds

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Forest Ecosystems 2024年第2期11卷 226-235页

作者： Nicolas Cattaneo stefano Puliti Carolin Fischer Rasmus Astrup Norwegian Institute of Bioeconomy Research(NIBIO) Division of Forest and Forest ResourcesHøgskoleveien 81433ÅsNorway

Mapping individual tree quality parameters from high-density LiDAR point clouds is an important step towards improved forest *** present a novel machine learning-based workflow that uses individual tree point clouds from drone laser scanning to predict wood quality indicators in standing *** object reconstruction methods,our approach is based on simple metrics computed on vertical slices that summarize information on point distances,angles,and geometric attributes of the space between and around the *** models use these slice metrics as predictors and achieve high accuracy for predicting the diameter of the largest branch per log (DLBs) and stem diameter at different heights (DS) from survey-grade drone laser *** show that our models are also robust and accurate when tested on suboptimal versions of the data generated by reductions in the number of points or emulations of suboptimal single-tree segmentation *** approach provides a simple,clear,and scalable solution that can be adapted to different situations both for research and more operational mapping.

关键词： UAV laser scanning Wood quality Machine learning Point cloud metrics

Optimized generation of entanglement based on the f-STIRAP technique

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Communications in Theoretical Physics 2024年第7期76卷 37-43页

作者： Dongni Chen Jiahui Li stefano Chesi Ying-Dan Wang Department of Physics Korea UniversitySeoul 02841South Korea School of Quantum Information Future Technology Henan UniversityZhengzhou 450046China Beijing Computational Science Research Center Beijing 100193China Department of Physics Beijing Normal UniversityBeijing 100875China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

We consider generating maximally entangled states(Bell states)between two qubits coupled to a common bosonic mode,based on *** the systematic approach developed by Wang et al(2017 New ***.19093016),we quantify the effects of non-adiabatic leakage and system dissipation on the entanglement generation,and optimize the entanglement by balancing non-adiabatic leakage and system *** find the analytical expressions of the optimal coupling profile,the operation time,and the maximal *** findings have broad applications in quantum state engineering,especially in solid-state devices where dissipative effects cannot be neglected.

关键词： f-STIRAP entanglement optimization perturbation theory

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