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81.
采用MEDISON SA-600型超声实时显像仪,以妊娠囊作为主要的判断依据,对658只配种实验猕猴进行早期妊娠诊断的探索。结果表明:妊娠15d诊断准确率为95.5%,20d诊断准确率为100%。同时对猕猴妊娠各期B超影像的特征及猕猴检测的操作特点进行论述。 相似文献
82.
The relationships of live animal muscular and skeletal scores and ultrasound measurements and carcass conformation and fat scores with carcass composition and value were determined using 74 bulls. The animals consisted of 53 late-maturing breed crosses and 21 Holstein–Friesian slaughtered at 13 to 17 months of age. They were offered concentrates ad-libitum and 1 kg of grass silage dry matter per head daily for the final 139 day finishing period. Live animal muscular and skeletal scores and ultrasonic muscle and fat depth measurements of the M. longissimus dorsi were recorded at 8 to 12 months of age and pre-slaughter. Following slaughter, carcasses were classified for conformation and fatness and the right side of each carcass was dissected into meat, fat and bone. Carcass conformation and fat scores, (scale 1 to 15) ranged from 4.7 to 14.4 and 2.7 to 11.5, respectively. Pre-slaughter muscular scores showed significant positive correlations with kill-out proportion (r = 0.82), carcass meat proportion (r = 0.72), conformation score (r = 0.94), carcass value (r = 0.72), and the proportion of high-value meat cuts in the carcass (r = 0.49), and significant negative correlations with carcass bone (r = − 0.89) and fat (r = − 0.32) proportions. The associations between pre-slaughter muscular scores and proportion of high-value cuts in meat, perinephric plus retroperitoneal fat and fat score were not significant. Corresponding correlations with muscular scores at 8 to 12 months of age were generally lower than those recorded pre-slaughter. Correlations of ultrasound muscle depth with carcass traits showed similar trends but lower values to those obtained using the muscular scoring procedure. Ultrasound fat depth pre-slaughter was positively correlated with carcass fat proportion (r = 0.56) and fat score (r = 0.54), and negatively correlated with carcass meat proportion, proportion of high-value cuts and carcass value. Correlations with other carcass traits were not significant. Correlations of live animal skeletal scores with carcass traits were generally non-significant. A one unit (scale 1–15) increase in carcass conformation score was associated with significant increases in kill-out proportion, meat yield and carcass value of 11.9 g/kg, 11.9 g/kg and 5.8 cent/kg, respectively. Corresponding effects for a one unit change in fat score were − 2.9 g/kg, − 11.1 g/kg and − 4.9 c/kg. In conclusion, live animal muscular scores and ultrasound measurements and carcass conformation and fat scores were shown to be useful predictors of carcass composition and value. 相似文献
83.
Coarse woody debris (CWD) has been recognized as one of the strongest indicators of forest biodiversity and its assessment has been emphasized in the development of new inventory methods. In this study, the most commonly referenced probability sampling methods were tested in a field area of 305.8 ha to gain comparative information on their performance and efficiency. Simple random sampling (SRS), systematic sampling and cluster sampling with fixed sized circular sample plots were tested, as well as strip sampling, transect relascope sampling and adaptive cluster sampling (ACS). Point relascope sampling and line intersect sampling were also tested for inventories of downed dead wood volumes. In addition, the amount of standing dead wood was assessed by means of traditional small angle relascope sampling. In general, the use of additional information in the inventory process has shown promising results. A new method for using data derived from airborne laser scanning (ALS) as a source of auxiliary information in the assessment of CWD volumes is presented, using probability proportional to size (PPS) sampling for the selection of the first-stage sample units in ACS (ACSPPS) and for the placement of fixed sized plots (PLOTPPS). The sampling methods were compared in terms of the cost-effectiveness. Point relascope sampling proved the most efficient sampling method for inventorying CWD volumes. PLOTPPS and ACSPPS were more efficient than the inventory of fixed sized plots (PLOTSRS) and ACS (ACSSRS) where sample units were selected with SRS. However, these methods could not achieve the same efficiency as relascope samplings. Nevertheless, the use of probability layers derived from ALS data gave promising results and offers new possibilities for inventorying CWD volumes more efficiently. 相似文献
84.
The antifungal effects of citral, eugenol, nerolidol and α-terpineol on Trichophyton mentagrophytes were investigated. Citral over 0.1 mg/ml strongly inhibited the hyphal growth of T. mentagrophytes, and the antifungal activity of α-terpineol was less effective. The morphological changes of the fungus exposed to the terpenes were observed by electron microscopy. The hyphae were distorted and collapsed at 0.2, 0.4 and 1 mg/ml of eugenol, nerolidol and α-terpineol respectively, and cell membrane and organelles were irreversibly damaged at 0.2 mg/ml citral. 相似文献
85.
云南木蠹象触角感器的扫描电镜观察 总被引:2,自引:0,他引:2
利用扫描电镜对云南木蠹象雌雄成虫触角上的感器进行观察和研究.结果表明:云南木蠹象成虫触角膝状,由柄节、梗节和鞭节组成,其中鞭节由7个亚节组成.在雌、雄成虫触角上均存在6种感器,即毛形感器、锥形感器、脚形感器、芽形感器、端指形感器和腔形感器,其中毛形感器和端指形感器的数量较多;此外,雌成虫触角还有双芽形感器,雄成虫触角上还有耳形感器.与端指形感器、脚形感器、双芽形感器结构相同的感器在鞘翅目已有的研究资料中还未见报道.是新发现的昆虫触角感器.对云南木蠹象触角不同种类感器的形态、分布以及雌雄间触角感器的分布和数量差异进行描述. 相似文献
86.
87.
针对粮仓特点,设计了基于RS485总线的集散式温度巡检系统.该系统以数字式单总线温度传感器DS18820为核心,采用C8051F005单片机作为变送器控制核心,实现DS18820温度数据的采集与总线控制.系统在电路板设计、布线、总线接口等方面采取了抗干扰措施,有效地避免了由于干扰信号、雷电等因素造成系统损坏的可能,提高了系统的可靠性.控制室计算机与各温度节点采用主从工作方式,由控制室计算机实现对各温度节点信息的采集、显示与存储.系统长期工作表明:利用RS485总线实现的集散式温度巡检系统,可靠性高,方便与现有其他工业现场RS485总线连接,扩大了应用范围. 相似文献
88.
Yoshiharu Nishiyama 《Journal of Wood Science》2009,55(4):241-249
The current structural models of the cellulose microfibril as well as its mechanical and thermal properties are reviewed.
The cellulose microfibril can be considered as a single thin and long crystalline entity with highly anisotropic physical
properties. The contribution and limit of different methods employed such as electron microscopy, infrared spectroscopy, X-ray
scattering and diffraction, solid state nuclear magnetic resonance spectroscopy, and molecular modeling are also discussed. 相似文献
89.
以黑胡桃木材为对象,采用X射线扫描含水率分布测试方法,分析、比较了微波干燥与常规热风干燥过程中木材内部含水率动态分布规律.结果表明:在微波干燥和常规热风干燥过程中,木材内层含水率均高于表层,存在着整体性的内高外低的含水率梯度场;在接个微波干燥过程中,木材内部虽然出现了部分内层含水率低于外层的情况,存在着含水率分布的局部不均匀,但并未出现与常规热风干燥相反的含水率梯度;在微波干燥中,木材内部各层与表层含水率的差值随着干燥时间的延长逐渐降低.随着干燥过程的进行,常规热风干燥中木材芯层与表层含水率差呈现出先增加后减小的变化趋势. 相似文献
90.