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1.
Colostrum is essential for good neonate health; however, it is not known whether different calves absorb the nutrients from colostrum equally well. In this study, the absorption of protein, IgG, and γ-glutamyl transferase was compared in newborn dairy bull calves for 1 wk after feeding colostrum from different sources. Thirty-five Holstein-Friesian bull calves were randomly allocated into 3 groups and fed colostrum within 4 h after birth. Group A calves (n = 12) were bottle fed colostrum from their own dam for 3 d. Colostrum from these group A cows was also used as foster cow colostrum for the group B calves (n = 12), such that each group A and B calf pair received identical colostrum from each milking of the respective group A dam (10% of birth weight per day). The group C calves (n = 11) were fed 1 bottle (2 L) of pooled colostrum and transition milk (referred to as pooled colostrum), as was the standard practice on the dairy farm. The pooled colostrum was collected from the other dairy cows on the farm 0 to 4 d postpartum and stored at 4°C for less than 12 h. Blood was sampled from calves before the first feeding and at 1, 2, 3, and 7 d after birth. Levels of total solids, total protein, and IgG were higher in the dam colostrum than in the pooled colostrum. At birth, there were no differences between the calf groups for any measurements, and all calves had very low IgG levels. After receiving colostrum, the glucose, plasma γ-glutamyl transferase, serum total protein, and IgG concentrations increased significantly in all calves. There were no differences in any blood measurements at any time point between the pairs of group A and group B calves that received colostrum from the same cow except for the IgG concentration 2 d after birth. However, the group A calves had a higher total serum protein level and IgG concentration than the group C calves for all the time points after the first feeding. The group B calves had a higher IgG concentration than the group C calves on d 1, 2, and 7 after birth. Compared with groups A and B, there was no difference in the proportion of calves in group C that failed to have passive immunity transferred adequately based on the IgG threshold (<10 g/L). Thus, the calves receiving identical colostrum from the same cow had the same levels of IgG, and even the pooled colostrum provided sufficient transfer of IgG as the calves were fed within 4 h after birth.  相似文献   
2.
越南太原省大慈县文安乡位于三岛国家公园管理处,社区居民生活困难,收入低,所以目前森林资源侵害状况依然存在。其中,25-50岁的群人对森林资源的影响最大,50岁以上和16岁以下的群人对森林资源的影响较小。人们对森林资源的影响是:伐木,狩猎动物,收集柴火,收集蔬菜,收集竹笋、药用植物。统计结果表明,天然林中具有18种树木经常被开发利用,常用木柴12种,药用29种,食用17种。7种动物经常被猎食。这些影响使得森林结构相当大改变,生物多样性减少,森林结构破坏。造成这种情况的主要原因是人们意识不高,缺乏工作机会,缺乏耕种土地,农业生产没有满足用户的需求。因此,必要有有关部门的协调在违法森林法的处理,为人民改善物质和精神生活,教育宣传和提高执法的认识  相似文献   
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4.
The basic ideas underlying an Estelle-C compiler, which accepts an Estelle protocol specification and produces a protocol implementation in C, are presented. The implementation of the ISO (International Organization for Standardization) class-2 transparent protocol, using the semiautomatic approach, is discussed. A manual implementation of the protocol is performed and compared to the semiautomatic implementation. The semiautomatic approach to protocol implementation offers several advantages over the conventional manual one, including correctness and modularity in protocol implementation code, conformance to the specification, and reduction in implementation time. Finally, ongoing development of a new Estelle-C compiler is presented  相似文献   
5.
The International Telecommunication Union (ITU) has completed work on a series of standards on asynchronous transfer mode (ATM) equipment functional operations and network element management. The objective of these standards is to enable flexible design and interoperability of network elements for use in a global ATM network, independent of any specific implementation. This article discusses these standards with respect to their development and application in planning ATM networks. Specifically, it addresses the following: the modeling approach taken in the development of the ITU standards, key operational features specified in the ATM network element functional model, and the capabilities of the ATM network element management interface. Examples of ATM equipment are provided to illustrate how the functional models specified in the ITU standards may be used by network planners and equipment manufacturers to specify and develop ATM equipment tailored to specific needs, while ensuring network interoperability. The article concludes with some points on the future enhancement of these and related ATM equipment operations standards  相似文献   
6.
In this paper, we propose a framework for human action analysis from video footage. A video action sequence in our perspective is a dynamic structure of sparse local spatial–temporal patches termed action elements, so the problems of action analysis in video are carried out here based on the set of local characteristics as well as global shape of a prescribed action. We first detect a set of action elements that are the most compact entities of an action, then we extend the idea of Implicit Shape Model to space time, in order to properly integrate the spatial and temporal properties of these action elements. In particular, we consider two different recipes to construct action elements: one is to use a Sparse Bayesian Feature Classifier to choose action elements from all detected Spatial Temporal Interest Points, and is termed discriminative action elements. The other one detects affine invariant local features from the holistic Motion History Images, and picks up action elements according to their compactness scores, and is called generative action elements. Action elements detected from either way are then used to construct a voting space based on their local feature representations as well as their global configuration constraints. Our approach is evaluated in the two main contexts of current human action analysis challenges, action retrieval and action classification. Comprehensive experimental results show that our proposed framework marginally outperforms all existing state-of-the-arts techniques on a range of different datasets.  相似文献   
7.
The activation of transducin (T) by photoexcited rhodopsin (R*) is kinetically dissected within the framework of Michaelis-Menten enzymology, taking transducin as substrate of the enzyme R*. The light scattering "release" signal (Vuong, T.M., M. Chabre, and L. Stryer, 1984, Nature (Lond.). 311:659-661) was used to monitor the kinetics of transducin activation at 20 degrees C. In addition, the influence of nonuniform distributions of R* on these activation kinetics is also explored. Sinusoidal patterns of R* were created with interference fringes from two crossed laser beams. Two characteristic times were extracted from the Michaelis-Menten analysis: t(form), the diffusion-related time needed to form the enzyme-substrate R*-transducin is 0.25 +/- 0.1 ms, and T(cat), the time taken by R* to perform the chemistry of catalysis on transducin is 1.2 +/- 0.2 ms, in the absence of added guanosine diphosphate (GDP) and at saturating levels of guanosine triphosphate (GTP). With t(form) being but 20% of the total activation time t(form) + t(cat), transducin activation by R* is not limited by lateral diffusion. This is further borne out by the observation that uniform and sinusoidal patterns of R* elicited release signals of indistinguishable kinetics. When (GDP) = (GTP) = 500 microM, t(cat) is lengthened twofold. As the in vivo GDP and GTP levels are comparable, the exchange of nucleotides may well be the rate-limiting process.  相似文献   
8.
Effects of coralline lime on yield and nutrient uptake by sweet corn (Zea mays saccharata Sturt.) and peanut (Arachis hypogea) were studied at three locations in Western Samoa. Coarse (0-10 mm) coralline material containing 31.1% Ca and 1.67% Mg was used as lime. There were two modes of application: band and broadcast, and three rates: 6, 12 and 18 ton ha–1. In the highest rainfall location, marketable yields were increased by 250% for peanut and 160% for sweet corn by liming at 6 ton ha–1, relative to the unamended control. Peanut yield increases were associated with reduced Mn toxicity and/or with Ca and Mg deficiency. Sweet corn was less susceptible to Mn toxicity, but more responsive to exchangeable Ca. The critical level of exchangeable Ca was found to be about 2.0 cmol(+)kg–1. Applying lime to a band of 0.25-m wide did not reduce yield relative to broadcast. Soil cultivation caused the lime to spread over a wider band, diluting the applied calcium with a larger soil volume, suggesting that less than 6 ton ha–1 broadcast coarse coralline lime could still be adequate for most Samoan soils.  相似文献   
9.
Designing amino acid sequences to fold with good hydrophobic cores   总被引:3,自引:0,他引:3  
We present two methods for designing amino acid sequences ofproteins that will fold to have good hydrophobic cores. Giventhe coordinates of the desired target protein or polymer structure,the methods generate sequences of hydrophobic (H) and polar(P) monomers that are intended to fold to these structures.One method designs hydrophobic inside, polar outside; the otherminimizes an energy function in a sequence evolution process.The sequences generated by these methods agree at the levelof 60–80% of the sequence positions in 20 proteins inthe Protein Data Bank. A major challenge in protein design isto create sequences that can fold uniquely, i.e. to a singleconformation rather than to many. While an earlier lattice-basedsequence evolution method was shown not to design unique folders,our method generates unique folders in lattice model tests.These methods may also be useful in designing other types offoldable polymer not based on amino acids  相似文献   
10.
Using time-series data analysis for stock-price forecasting (SPF) is complex and challenging because many factors can influence stock prices (e.g., inflation, seasonality, economic policy, societal behaviors). Such factors can be analyzed over time for SPF. Machine learning and deep learning have been shown to obtain better forecasts of stock prices than traditional approaches. This study, therefore, proposed a method to enhance the performance of an SPF system based on advanced machine learning and deep learning approaches. First, we applied extreme gradient boosting as a feature-selection technique to extract important features from high-dimensional time-series data and remove redundant features. Then, we fed selected features into a deep long short-term memory (LSTM) network to forecast stock prices. The deep LSTM network was used to reflect the temporal nature of the input time series and fully exploit future contextual information. The complex structure enables this network to capture more stochasticity within the stock price. The method does not change when applied to stock data or Forex data. Experimental results based on a Forex dataset covering 2008–2018 showed that our approach outperformed the baseline autoregressive integrated moving average approach with regard to mean absolute error, mean squared error, and root-mean-square error.  相似文献   
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