单穗玉米水分、质量连续测量及封装系统设计

设计了基于电容式水分测量装置的考种设备,可以自动连续测量单穗玉米籽粒的水分、质量的数据,并对测量完的整穗玉米籽粒进行封装喷码。整机由斗式送料机构、电容式水分测量仪、翻转模块、封装机及控制部分组成。根据整机的工作原理,采用带传动和料斗组合实现籽粒的输送,LDS-1G型电容式水分测量装置来获取籽粒水分、质量参数;配备自动封装的模块,利用SIEMENS LOGO!逻辑控制器来实现各个环节的控制,配合籽粒参数的测量。针对玉米籽粒试验验证表明:其最大测量速度为12s/穗,处理最大通量可达7 200穗/天。

From Phenotypes to Molecules: Revolutionizing Gut Microbiota Identification Methods

The gut microbiota is a complex ecosystem composed of many bacteria and their metabolites.It plays an irreplaceable role in human digestion,nutrient absorption,energy supply,fat metabolism,immune regulation,and many other aspects.Exploring the structure and function of the gut microbiota,as well as their key genes and metabolites,will enable the early diagnosis and auxiliary diagnosis of diseases,new treatment methods,better effects of drug treatments,and better guidance in the use of antibiotics.The identification of gut microbiota plays an important role in clinical diagnosis and treatment,as well as in drug research and development.Therefore,it is necessary to conduct a comprehensive review of this rapidly evolving topic.Traditional identification methods cannot comprehensively capture the diversity of gut microbiota.Currently,with the rapid development of molecular biology,the classification and identification methods for gut microbiota have evolved from the initial phenotypic and chemical identification to identification at the molecular level.This review integrates the main methods of gut microbiota identification and evaluates their application.We pay special attention to the research progress on molecular biological methods and focus on the application of high-throughput sequencing technology in the identification of gut microbiota.This revolutionary method for intestinal flora identification heralds a new chapter in our understanding of the microbial world.

The Influence of Wave State and Sea Spray on Drag Coefficient from Low to High Wind Speeds

Ocean waves alter the roughness of sea surface,and sea spray droplets redistribute the momentum flux at the air-sea interface.Hence,both wave state and sea spray influence sea surface drag coefficient.Based on the new sea spray generation function which depends on sea surface wave,a wave-dependent sea spray stress is obtained.According to the relationship between sea spray stress and the total wind stress on the sea surface,a new formula of drag coefficient at high wind speed is acquired.With the analysis of the new drag coefficient,it is shown that the drag coefficient reduces at high wind speed,indicating that the sea spray droplets can limit the increase of drag coefficient.However,the value of high wind speed corresponding to the initial reduced drag coefficient is not fixed,and it depends on the wave state,which means the influence of wave cannot be ignored.Comparisons between the theoretical and measured sea surface drag coefficients in field and laboratory show that under different wave ages,the theoretical result of drag coefficient could include the measured data,and it means that the new drag coefficient can be used properly from low to high wind speeds under any wave state condition.

High Throughput Satellite System Capacity Analysis and Application Forecast

With the development of large numbers broadband Internet access,global satellite communications is moving towards High Throughput Satellites(HTS).Now,USA,Canada,Europe,Thailand,Japan,United Arab Emirates,Australia have already developed HTS systems.However,there is little research to analyze the factors influencing high throughput.Thus,from the design perspective,the throughput of HTS and influencing factors are calculated and compared at a system level.Finally,the application of HTS is analyzed and forecasted.

Estimates of global M_2 internal tide energy fluxes using TOPEX/POSEIDON altimeter data

TOPEX/POSEIDON altimeter data from October 1992 to June 2002 are used to calculate the global barotropic M2 tidal currents using long-term tidal harmonic analysis. The tides calculated agree well with ADCP data obtained from the South China Sea （SCS）. The maximum tide velocities along the semi-major axis and semi-minor axis can be computed from the tidal ellipse. The global distribution of M2 internal tide vertical energy flux from the sea bottom is calculated based on a linear internal wave generation model. The global vertical energy flux of M2 internal tide is 0.96 TW, with 0.36 TW in the Pacific, 0.31 TW in the Atlantic and 0.29 TW in the Indian Ocean, obtained in this study. The total horizontal energy flux of M2 internal tide radiating into the open ocean from the lateral boundaries is 0.13 TW, with 0.06 TW in the Pacific, 0.04TW in the Atlantic, and 0.03 TW in the Indian Ocean. The result shows that the principal lunar semi-diurnal tide Me provides enough energy to maintain the large-scale thermohaline circulation of the ocean.

水稻表型组学研究概况和展望

水稻功能基因组学和水稻育种研究都已进入大规模、高通量时代。表型信息获取与分析是水稻功能基因组学和现代作物育种研究的基础。目前,表型检测主要停留在传统人工获取的阶段,劳动量大,效率低,对大批量水稻样本的生长测量几乎不可行,表型数据的质量受人工主观因素影响也较大。某些表型参数的获取还需破坏性测量,无法实现连续测量。近年来,表型组学的兴起给解决这一问题带来了新的契机。现以水稻为主,对表型组学的国内外研究现状展开综述,并对表型组学的未来进行分析与展望。

基于环形谐振器的无标记光学生物传感器

光学生物传感技术将生物分子相互作用转换为可量化的光信号,用以生物医药分析及健康科学等领域。无标记生物传感技术具有直接实时检测等优势,适宜进行高通量实时定量测量,可获得较高的灵敏度。本文介绍基于环形谐振器的若干光学无标记传感器的工作原理、特性、结构和应用。且应用于蛋白质、病毒、细菌制剂等药物时,不会对待测物分子产生结构性和功能性的改变。生物传感器具有良好的应用效果和广阔的前景。

Understanding human diseases with high-throughput quantitative measurement and analysis of molecular signatures

Microarray and deep sequencing technologies have provided unprecedented opportunities for mapping genome mutations,RNA transcripts,transcription factor binding,and histone modifications at high resolution at the genome-wide level.This has revolutionized the way in which transcriptomes,regulatory networks and epigenetic regulations have been studied and large amounts of heterogeneous data have been generated.Although efforts are being made to integrate these datasets unbiasedly and efficiently,how best to do this still remains a challenge.Here we review major impacts of high-throughput genome-wide data generation,their relevance to human diseases,and various bioinformatics approaches for data integration.Finally,we provide a case study on inflammatory diseases.

Development of a colorimetric assay for rapid quantitative measurement of clavulanic acid in microbial samples

We developed a colorimetric assay to quantify clavulanic acid （CA） in culture broth of Streptomyces clavuligerus, to facilitate screening of a large number of S. clavuligerus mutants. The assay is based on a β-1actamase-catalyzed reaction, in which the yellow substrate nitrocefin （λmax=390 nm） is converted to a red product （λmax=486 nm）. Since CA can irreversibly inhibit β-1actamase activity, the level of CA in a sample can be measured as a function of the A390]A486 ratio in the assay mixture. The sensitivity and detection window of the assay were determined to be 50 μg L -1 and 50 μg L to 10 mg L-1, respectively. The reliability of the assay was confirmed by comparing assay results with those obtained by HPLC. The assay was used to screen a pool of 65 S. clavuligerus mutants and was reliable for identifying CA over-producing mutants. Therefore, the assay saves time and labor in large-scale mutant screening and evaluation tasks. The detection window and the reliability of this assay are markedly better than those of previously reported CA assays. This assay method is suitable for high throughput screening of microbial samples and allows direct visual observation of CA levels on agar plates.