ω-3长链多不饱和脂肪酸对母猪繁殖性能的影响

长链多不饱和脂肪酸(LC PUFAs)在母猪营养中的作用经常被人们研究,因为猪场的盈利能力主要取决于母猪的繁殖性能。根据以往的研究结果,母猪妊娠期喂食ω-3 LC PUFAs可以减少前列腺素的合成,提高胚胎存活率和仔猪初生重;哺乳期饲喂ω-3 LC PUFAs可以提高乳汁中EPA和DHA含量,改善哺乳仔猪肠道健康和断奶重。文章论述了LC PUFAs(主要是ω-3)对现代高产母猪繁殖性能的影响,为在生产实践中合理添加应用LC PUFAs,提高母猪生产性能提供理论参考。

Combination of a crude oil-degrading bacterial consortium under the guidance of strain tolerance and a pilot-scale degradation test

Under the guidance of strain tolerance, a new combination method for crude oil-degrading bacterial consortium was studied. Firstly, more than 50 efficient crude oil-degrading and biosurfactant producing bacteria were isolated from petroleum-contaminated soil and water in Tianjin Binhai New Area Oil field, China. Twenty-four of them were selected for further study. These strains were identified as belonging Pseudornonas aeruginosa, Bacillus subtilis, Brevibacillus brevis, Achrornobacter sp., Acinetobacter venetianus, Lysinibacillus rnacroides, Klebsiella oxytoca, Stenotrophornonas rhizophila, Rhodococcus sp. and Bacillus thuringiensis. A shake-flask degradation test revealed that 12 of these strains could degrade over 50% of 1% crude oil concentration in 7 d. Of these, 8 strains were able to produce biosurfactants. Furthermore, environmental tolerance experiments indicated that the majority of the strains had the ability to adapt to extreme environments including high temperatures, alkaline en- vironments and high salinity environments. A mixed bacterial agent comprising the strains WB2, W2, W3 and HA was developed based on the environmental tolerance tests and subjected to the pilot-scale degradation test indicating that this bacterial agent could degrade 85.2% of 0.8% crude oil concentration in 60 d. Our results suggest that the application of this mixed agent could remediate crude oil polluted soils in saline and alkaline environments.

Forward modeling and inversion of the relation model between the gas content of plume and its seismic attribute

The methane bubble plume attracts interest because it offers direct evidence of seafloor gas leakage and plays an indirect role in the exploration and identification of natural gas hydrate.In this study,based on established plume models and their migration sections,three amplitude-class attributes were extracted from three formations for the migration sections of five plumes,and the correlation between the gas content and seismic attribute was obtained.As the gas content increases,the amplitude attribute correspondingly increases,and the linear correlation is relatively good.Moreover,correlation coefficients between gas content and amplitude attributes are close to 1.0.By using linear fitting,the relation model between the gas content of the plume and the seismic attribute was obtained.The relation model was subsequently used to invert the gas content from a real databearing plume.Comparison of the gas content section of the plume with the attribute section and real seismic section reveals common distribution characteristics,namely,the color of the section in the lower right corner is dark.If the amplitude value is large in the seismic section of the real plume,the amplitude attribute value is also large in the corresponding attribute section,and the inverted value of the gas content is also large(because gas content and amplitude are linearly correlated),which indicates that the plume bubbles of the section in the lower right corner is intensively distributed.Finally,the obtained gas content section of the plume can reflect the distribution of the plume bubble content more simply and intuitively,from which the distribution law of seafloor bubbles can be deduced,and this lays a foundation for the further estimation of the gas content of the plume and hydrate reserves.

改制型家族企业更愿意进行长期投资吗?——基于心理所有权视角的分析

国有企业改制作为中国经济转型的重要举措,是中国民营家族企业的独特来源,对民营家族企业的长期可持续发展有着深远的影响。本文聚焦于改制这一独特的历史数据分析组织历史来源对中国民营家族企业长期投资导向的影响。基于2008~2016年中国上市家族企业数据,得出以下结论:第一,改制型家族企业由于企业家的心理所有权较弱,企业长期投资水平相对较低。第二,企业家在改制前进入企业的情况下,由于对企业拥有更高水平的熟悉度和认同感,会有更高水平的心理所有权,进而使改制型企业在长期投资中更加积极。第三,欠发达的制度环境将强化心理所有权较弱的企业家的不确定性规避倾向,进而削弱企业的长期投资水平。本文揭示了影响中国民营家族企业长期投资导向的重要历史因素,并为中国民营经济的长期存续提供了可行的建议。

两型饲料的能量和新型蛋白质替代原料

两型饲料是指资源节约型和环境友好型饲料。目前,市场上猪、肉鸡和蛋鸡的日粮以玉米豆粕型为主,需要新的解决方案来改善饲料生产可持续性和解决工农争粮问题。有许多原料可作为替代能量和蛋白质来源正受到人们的关注,其中包括高粱、大麦、昆虫源性原料、藻源性蛋白和单细胞蛋白等。文章主要论述了两型饲料中纤维的重要性以及几种能量和新型蛋白质替代猪只饲料原料的应用前景。

Detection of new candidate genes controlling seed weight by integrating gene coexpression analysis and QTL mapping in Brassica napus L.

Seed weight is a component of seed yield in rapeseed(Brassica napus L.).Although quantitative trait loci(QTL)for seed weight have been reported in rapeseed,only a few causal quantitative trait genes(QTGs)have been identified,resulting in a limitation in understanding of seed weight regulation.We constructed a gene coexpression network at the early seed developmental stage using transcripts of 20,408 genes in QTL intervals and 1017 rapeseed homologs of known genes from other species.Among the 10 modules in this gene coexpression network,modules 1 and 2 were core modules and contained genes involved in source–flow–sink processes such as synthesis and transportation of fatty acid and protein,and photosynthesis.A hub gene SERINE CARBOXYPEPTIDASE-LIKE 19(SCPL19)was identified by candidate gene association analysis in rapeseed and functionally investigated using Arabidopsis T-DNA mutant and overexpression lines.Our study demonstrates the power of gene coexpression analysis to prioritize candidate genes from large candidate QTG sets and enhances the understanding of molecular mechanism for seed weight at the early developmental stage in rapeseed.

Identification of a candidate QTG for seed number per silique by integrating QTL mapping and RNA-seq in Brassica napus L.

Seed number per silique(SNPS)is one of seed yield components in rapeseed,but its genetic mechanism remains elusive.Here a double haploid(DH)population derived from a hybrid between female 6Q006with 35–40 SNPS and male 6W26 with 10–15 SNPS was investigated for SNPS in the year 2017,2018,2019 and 2021,and genotyped with Brassica 60K Illumina Infinium SNP array.An overlapping major QTL(qSNPS.C09)explaining 51.50%of phenotypic variance on average was narrowed to a 0.90 Mb region from 44.87 Mb to 45.77 Mb on chromosome C09 by BSA-seq.Subsequently,two DEGs in this interval were detected between extreme individuals in DH and F_2populations by transcriptome sequencing at7 and 14 days after pollination siliques.Of which,BnaC09g45400D encoded an adenine phosphoribosyltransferase 5(APT5)has a 48-bp InDel variation in the promoter of two parents.Candidate gene association analysis showed that this InDel variation was associated with SNPS in a nature population of rapeseed,where 54 accessions carrying the same haplotype as parent 6Q006 had higher SNPS than103 accessions carrying the same haplotype as parent 6W26.Collectively,the findings are helpful for rapeseed molecular breeding of SNPS,and provide new insight into the genetic and molecular mechanism of SNPS in rapeseed.

Optical properties and surface energy flux of spring fast ice in the Arctic

Over the past decades,sea ice in the polar regions has been significantly affecting local and even hemispheric climate through a positive ice albedo feedback mechanism.The role of fast ice,as opposed to drift ice,has not been well-studied due to its relatively small coverage over the earth.In this paper,the optical properties and surface energy balance of land fast ice in spring are studied using in situ observations in Barrow,Alaska.The results show that the albedo of the fast ice varied between 0.57 and 0.85 while the transmittance increased from 1.3×10-3 to 4.1×10-3 during the observation period.Snowfall and air temperature affected the albedo and absorbance of sea ice,but the transmittance had no obvious relationship with precipitation or snow cover.Net solar shortwave radiation contributes to the surface energy balance with a positive 99.2%of the incident flux,with sensible heat flux for the remaining 0.8%.Meanwhile,the ice surface loses energy through the net longwave radiation by 18.7%of the total emission,while the latent heat flux accounts for only 0.1%.Heat conduction is also an important factor in the overall energy budget of sea ice,contributing 81.2%of the energy loss.Results of the radiative transfer model reveal that the spectral transmittance of the fast ice is determined by the thickness of snow and sea ice as well as the amount of inclusions.As major inclusions,the ice biota and particulates have a significant influence on the magnitude and distribution of the spectral transmittance.Based on the radiative transfer model,concentrations of chlorophyll and particulate in the fast ice are estimated at 5.51 mg/m^(2)and 95.79 g/m^(2),which are typical values in the spring in Barrow.

Multilayer graphene refractive index tuning by optical power

Graphene’s optical absorption coefficient increases linearly with the number of layers making it more effective in the construction of optical tuning graphene-based devices. Refractive index(RI) is one of the important optical parameters of the graphene for accurately describing its optical characteristics and further applications. In view of the RI research of the multilayer graphene is lacking and existing measurement methods are complicated. Optical power tuning RI of multilayer graphene is investigated using a simple measurement and no temperature cross sensitivity all optical fiber sensing structure.Optical power tuning RI characteristics of multilayer graphene are studied by tuning the introducing broad band light power from 0.57 mW to 22.7 m W. Different thickness graphene coating shows different tuning efficiency. At 4.86-μm thickness,a 3.433-nm Bragg wavelength shift is obtained with 156.2-pm/mW wavelength versus optical power tuning sensitivity corresponding to 3.25×10~3 RI change and 0.154 URI/W(URI, unit of RI) RI optical power tuning efficiency.

Oceanic vertical mixing of the lower halocline water in the Chukchi Borderland and Mendeleyev Ridge

Oceanic vertical mixing of the lower halocline water(LHW)in the Chukchi Borderland and Mendeleyev Ridge was studied based on in situ hydrographic and turbulent observations.The depth-averaged turbulent dissipation rate of LHW demonstrates a clear topographic dependence,with a mean value of 1.2×10^(-9) W/kg in the southwest of Canada Basin,1.5×10^(-9) W/kg in the Mendeleyev Abyssal Plain,2.4×10^(-9) W/kg on the Mendeleyev Ridge,and2.7×10^(-9) W/kg on the Chukchi Cap.Correspondingly,the mean depth-averaged vertical heat flux of the LHW is0.21 W/m^(2) in the southwest Canada Basin,0.30 W/m^(2) in the Mendeleyev Abyssal Plain,0.39 W/m^(2) on the Mendeleyev Ridge,and 0.46 W/m^(2) on the Chukchi Cap.However,in the presence of Pacific Winter Water,the upward heat released from Atlantic Water through the lower halocline can hardly contribute to the surface ocean.Further,the underlying mechanisms of diapycnal mixing in LHW—double diffusion and shear instability—was investigated.The mixing in LHW where double diffusion were observed is always relatively weaker,with corresponding dissipation rate ranging from 1.01×10^(-9) W/kg to 1.57×10^(-9) W/kg.The results also show a strong correlation between the depth-average dissipation rate and strain variance in the LHW,which indicates a close physical linkage between the turbulent mixing and internal wave activities.In addition,both surface wind forcing and semidiurnal tides significantly contribute to the turbulent mixing in the LHW.

Analysis on Relationship between Adjustment of Agricultural Structure and Urbanization Development

As a part of certain region,agricultural development has inevitable connection with regional urbanization,and they are highly heterogeneous and complementary in space. Their internal relationship is manifested as agricultural structure suits demand of urbanization development through adjustment in the process of urbanization,while urbanization is based on development of regional agriculture. From history of world agriculture and urbanization development,agriculture firstly provides primitive accumulation for urbanization development,and drives regional urbanization through promoting agricultural development. When urbanization develops to certain stage,urbanization accumulation increases and reaches the goal of " boosting urbanization through agriculture". If urbanization develops slowly,agricultural adjustment will lack motive force. On the contrary,weak agricultural development will lead to stagnation of urbanization. Therefore,adjustment of agricultural structure and urbanization development are interconnected,mutually promoted and restricted,and interdependent.

Survey on path and view planning for UAVs

Background In recent decades,unmanned aerial vehicles(UAVs)have developed rapidly and been widely applied in many domains,including photography,reconstruction,monitoring,and search and rescue.In such applications,one key issue is path and view planning,which tells UAVs exactly where to fly and how to search.Methods With specific consideration for three popular UAV applications(scene reconstruction,environment exploration,and aerial cinematography),we present a survey that should assist researchers in positioning and evaluating their works in the context of existing solutions.Results/Conclusions It should also help newcomers and practitioners in related fields quickly gain an overview of the vast literature.In addition to the current research status,we analyze and elaborate on advantages,disadvantages,and potential explorative trends for each application domain.

Acylfluorination of enynes via phosphine and silver catalysis

This work describes intermolecular acylfluorination of gem-difluoroenynes using acyl fluorides as both acyl source and fluorine source.Trifluoromethyl-substituted allenones or furans could be selectively achieved via phosphine and silver catalysis.These approaches exhibit high regioselectivity,atom econ-omy and broad functionality tolerance.

Optical colorimetric LiTaO_(3)wafers for highprecision lithography on frequency control of SAW devices

Surface acoustic wave(SAW)resonators based on lithium tantalate(LT,LiTaO_(3))wafers are crucial elements of mobile communication filters.The use of intrinsic LT wafers typically brings about low fabrication accuracy of SAW resonators due to strong UV reflection in the lithography process.This hinders their resonance frequency control seriously in industrial manufacture.LT doping and chemical reduction could be applied to decrease the UV reflection of LT wafers for high lithographic precision.However,conventional methods fail to provide a fast and nondestructive approach to identify the UV performance of standard single-side polished LT wafers for highprecision frequency control.Here,we propose a convenient on-line sensing scheme based on the colorimetry of reduced Fe-doped LT wafers and build up an automatic testing system for industrial applications.The levels of Fe doping and chemical reduction are evaluated by the lightness and color difference of LT-based wafers.The correlation between the wafer visible colorimetry and UV reflection is established to refine the lithography process and specifically manipulate the frequency performance of SAW resonators.Our study provides a powerful tool for the fabrication control of SAW resonators and will inspire more applications on sophisticated devices of mobile communication.

Intelligent identification method of insulation pull rod defects based on intactness-aware Mosaic data augmentation and fusion of YOLOv5s

The authors introduce the intactness-aware Mosaic data augmentation strategy,designed to tackle challenges such as low accuracy in detecting defects in insulation pull rods,limited timeliness in intelligent analysis,and the absence of a comprehensive database for information on insulation pull rod defects.The proposed strategy incorporates the YOLOv5s algorithm for detecting defects in insulation pull rods.Initially,the YOLOv5s network was constructed,and a dataset containing photos of insulation pull rods with white spots,fractures,impurities,and bubble flaws was compiled to capture images of defects.The research presented a data enhancement approach to improve the images and establish a dataset for insulation pull rod defects.The YOLOv5s algorithm was applied for both training and testing purposes.A comparative analysis was conducted to assess the detection performance of YOLOv5s against a conventional target detector for identifying defects in insulation pull rods.Furthermore,the utility of Mosaic's data augmentation technique,which incorporates intactness awareness,was evaluated to enhance the accuracy of identifying insulation pull rod defects.The research findings indicate that the YOLOv5s algorithm is employed for intelligent detection and precise localisation of flaws.The intactnessaware Mosaic data augmentation strategy significantly improves the accuracy of detecting faults in insulation pull rods.The YOLOv5s model used achieves a performance index mAP@0.5:0.95 of 0.563 on the test set,distinct from the training set data.With a threshold of 0.5,the mAP@0.5 score is 0.904,indicating a substantial improvement in both detection efficiency and accuracy compared to conventional target detection methods.Innovative approaches for identifying defects in insulation pull rods are introduced.

区域主要作物生产实体水-虚拟水耦合流动过程解析与评价

水安全是粮食安全的刚性基础.在农业生产过程中(产前、产中、产后)自然-经济-社会(三元)因素驱动下,其水资源消耗形成实体水-虚拟水(二维)嵌入转化、互为反馈、相互影响的耦合流动过程.本文基于实体水-虚拟水"二维三元"耦合流动理论,集成构建了以水量为参数的区域作物生产广义实体水-虚拟水耦合流动过程量化方法,并应用于我国"丝绸之路经济带"沿线西部六省,对其1985~2013年主要作物实体水-虚拟水耦合流动过程进行解析与评价.揭示了区域作物生产实体水-虚拟水耦合流动现象,发现六省间水资源消耗与流动存在资源与经济效益的此消彼长现象.表明以农田尺度实体节水为目标的资源单视角传统农业水资源管理理念,已不足以实现多空间尺度水资源的资源-经济同步高效利用的管理目标,而具有资源-经济-社会三重意义的区域农业全产业链实体水-虚拟水统筹管理应为有效解决思路.基于此,初步提出三点思考:(1)现代农业节水应实体水-虚拟水统筹考虑;(2)需加快突破农业生产实体水-虚拟水耦合流动量化、评价方法与调控关键技术;(3)建议基于农业全产业链视角,建立基于实体水-虚拟水二维度理论的农业水资源管理体系,确保实现各阶段水资源管理"三条红线".

创业者如何提升企业创业绩效:靠人力资本还是社会资本?

创业者人力资本和社会资本对企业创业绩效的影响受到学者们的广泛关注,然而现有研究较少比较人力资本和社会资本对企业创业绩效的作用。本研究基于市场转型理论,通过对中东西部地区4个城市106家企业的实证研究发现:(1)创业者的人力资本和社会资本对企业创业绩效都有正向影响;(2)创业者的社会资本对企业创业绩效的正向影响强于创业者的人力资本;(3)地区经济发展水平调节创业者的人力资本和社会资本对企业创业绩效的影响。其中,经济不发达地区创业者的人力资本和社会资本对企业创业绩效的影响均强于经济较发达地区。

Effect of organic amine alkali and inorganic alkali on benzotriazole removal during post Cu-CMP cleaning

Benzotriazole(BTA), an anticorrosion agent of slurry, is the main organic pollutant remaining after CMP of multilayer copper wiring, and also the main removal object of post CMP cleaning. The adsorption of BTA onto the copper could form a dense Cu-BTA film, which makes the copper surface strongly passivated. According to this characteristic, quantitative analysis of BTA residue after cleaning is carried out by contact angle measurement and electrochemical measurement in this paper. A scanning electron microscope(SEM) with EDX was used to observe and analyze the BTA shape and elements. The efficiencies of organic alkali and inorganic alkali on the removal of BTA were studied. The corresponding reaction mechanism was also analyzed. The results show that the adsorption structure of Cu(I)-BTA cannot be destroyed in an alkaline environment with a pH less than 10; the effect of BTA removal by inorganic alkali is worse than that of the organic amine alkali with the coordination structure under the same pH environment; the FA/O Ⅱ chelating agent with the fraction of 200 ppm can effectively remove BTA residue on the surface of copper wafer.

Development and optimization of thermal contrast amplification lateral flow immunoassays for ultrasensitive HIV p24 protein detection

Detection of human immunodeficiency virus(HIV)p24 protein at a single pg/ml concentration in point-of-care(POC)settings is important because it can facilitate acute HIV infection diagnosis with a detection sensitivity approaching that of laboratory-based assays.However,the limit of detection(LOD)of lateral flow immunoassays(LFAs),the most prominent POC diagnostic platform,falls short of that of laboratory protein detection methods such as enzyme-linked immunosorbent assay(ELISA).Here,we report the development and optimization of a thermal contrast amplification(TCA)LFA that will allow ultrasensitive detection of 8 pg/ml p24 protein spiked into human serum at POC,approaching the LOD of a laboratory test.To achieve this aim,we pursued several innovations as follows:(a)defining a new quantitative figure of merit for LFA design based on the specific to nonspecific binding ratio(BR);(b)using different sizes and shapes of gold nanoparticles(GNPs)in the systematic optimization of TCA LFA designs;and(c)exploring new laser wavelengths and power regimes for TCA LFA designs.First,we optimized the blocking buffer for the membrane and running buffer by quantitatively measuring the BR using a TCA reader.The TCA reader interprets the thermal signal(i.e.,temperature)of GNPs within the membrane when irradiated by a laser at the plasmon resonance wavelength of the particle.This process results in higher detection and quantitation of GNPs than in traditional visual detection(i.e.,color intensity).Further,we investigated the effect of laser power(30,100,200 mW),GNP size and shape(30 and 100 nm gold spheres,150 nm gold-silica shells),and laser wavelength(532,800 nm).Applying these innovations to a new TCA LFA design,we demonstrated that 100nm spheres with a 100 mW 532 nm laser provided the best performance(i.e.,LOD=8pg/ml).This LOD is significantly better than that of the current colorimetric LFA and is in the range of the laboratory-based p24 ELISA.In summary,this TCA LFA for p24 protein shows promise for detecting acute HIV infection in POC settings.

Direct observation of chaotic resonances in optical microcavities

Optical microcavities play a significant role in the study of classical and quantum chaos.To date,most experimental explorations of their internal wave dynamics have focused on the properties of their inputs and outputs,without directly interrogating the dynamics and the associated mode patterns inside.As a result,this key information is rarely retrieved with certainty,which significantly restricts the verification and understanding of the actual chaotic motion.Here we demonstrate a simple and robust approach to directly and rapidly map the internal mode patterns in chaotic microcavities.By introducing a local index perturbation through a pump laser,we report a spectral response of optical microcavities that is proportional to the internal field distribution.With this technique,chaotic modes with staggered mode spacings can be distinguished.Consequently,a complete chaos assisted tunneling(CAT)and its time-reversed process are experimentally verified in the optical domain with unprecedented certainty.