金华猪促黑激素皮质素受体4基因多态性分析

应用PCR—RFLP方法对金华猪Ⅰ系(154头)、金华猪Ⅱ系(41头)和金华猪Ⅲ系(53头)的MC4R基因的1269∽1494bp区段进行扩增，并用TaqⅠ酶进行酶切，比较了MC4R酶切后基因型频率分布情况。结果表明，AA基因型频率在金华猪上较高达到0．9194，在Ⅱ系中最高达到0．9512，Ⅲ系次之达到0．9434，Ⅰ系最低达到0．9026，而金华猪的AB基因型和BB基因型频率都较低分别为0．0565和0．0242。     

生长激素基因多态性与猪部分生产性能的关系

采用PCR-RFLP对南昌白猪(117头)和大约克夏猪(361头)的GH1基因的-119bp～+486bp进行了扩增,并用HhaⅠ酶切,产生4个等位基因:C1(605bp)、C2(498bp+107bp)、C3(449bp+156bp)和C4(449bp+107bp+49bp)。分析了不同基因型对平均初生重、2月龄体重、6月龄体重、料重比、校正背膘厚、平均背膘厚和瘦肉率等生产性能的影响。结果表明,在南昌白猪中,C2C2基因型猪的2月龄体重比C1C1基因型猪的大,差异显著(P<0.05)。在大约克夏猪中,C3C3基因型猪的初生重最小,与C2C4基因型猪的相比,差异极显著(P<0.01);C2C4基因型猪的6月龄体重最大,与C2C3和C3C3基因型猪的相比,差异显著(P<0.05)。     

母猪繁殖力与仔猪生产效益研究

选不同比例梅山猪血缘（1／4,3／4,1／2,1）杂种母猪和大白母猪共131头,在同一饲养条件下,对母猪的繁殖力和饲料消耗连续测定5个繁殖周期,研究母猪繁殖力高低对仔猪生产效益的影响,结果表明,梅山猪及其杂种母猪产仔数,断奶仔猪数显著高于大白母猪（P＜0．01）,经产1／4梅山,3／4梅山,1／2梅山,梅山的产全数分别比大白母猪多1．5,1．9,4．5,4．1头,断奶仔猪数分别多1．9,1．8,3．5,2．7头;梅山猪及其杂种母猪繁殖周期总耗料比大白猪少（P＜0．01）,梅山和1／2梅山母猪的仔猪生产成本最低,产仔数和断奶仔猪与母猪繁殖周期耗料呈线性变化,与仔猪每头分摊耗料呈倒数曲线变化。     

金华猪肌细胞生成素基因的初步研究

运用PCR-RFLP方法对金华猪I系(178头)、II系(30头)、III系(41头)的肌细胞生成素(MyoG)基因的第2内含子内(PCR1-MspⅠ-RFLP)和3''端(PCR2-MspⅠ-RFLP)位点进行多态性分析。结果表明,PCR1-MspⅠ-RFLP位点有3种基因型,即AA型、AB型和BB型,其基因型频率分别为0.1544、0.3826、0.4631;PCR2-MspⅠ-RFLP位点只有2种基因型,MM型和MN型,其基因型频率分别为0.9953和0.0047。     

按照仔猪吮乳规律合理固定乳头

固定仔猪吃奶乳头是提高仔猪成活率的重要措施之一。我们结合生产实践,对哺乳仔猪形成稳定吮乳位次的过程进行了观察,旨在弄清哺乳仔猪对乳头的占吮规律,为合理固定仔猪乳头提供依据。一、对仔猪固定乳头过程的观察 (一)材料与方法 1.选择县种猪场2头分娩期相同,各有7对乳头的经产母猪和所产28头仔猪做供试猪。不加人为干预,观察仔猪固定吮乳奶头的过程。 2.仔猪初生后打耳号,并用白胶布写上编号(与耳号同),剪毛后贴在仔猪背上.便于观察和记录。     

杜洛克,大白,长白三个品种相杂交后繁殖性状杂种优势表现的研究

在杜洛克、长白、大白三个纯种为基础的杂交繁育配套系中，测定了3个纯种及12个杂交组合的827头次分娩母猪的繁殖性状（产仔总数、产活仔数、初生重、21天成活数、21天个体重、窝重），明确了3个纯种繁殖性状及各杂交组合杂种优势表现情况。结果显示，二元杂交猪比纯种猪在产活仔数、初生重等方面有极显著的杂种优势，三元杂交猪比纯种亲本在产仔总数、产活仔数、初生重、21天成活数等性状上均有极显著的杂种优势；在各正反交组合中，YL组合比LY组合在初生重、21天个体重上有显著的差异，YL优于LY，而在三元杂交组合中，各性状比较均无明显差异，在回交组合中，L．YL组合产仔数明显优于L．LY组合，Y．LY组合21天个体重明显优于Y．YL组合，纯种中在繁殖上L略优于Y，但无显著差异。     

采用开放式群体继代选育法和分子生物技术相结合选育高产大约克夏母系

采用开放式群体继代选育法和分子生物技术结合选育大约克夏母系,效果较为显著。核心群内已淘汰氟烷应激敏感基因;与零世代相比,Ⅱ世代母猪的头胎产仔数增加0.88头,产活仔数增加0.80头,初生窝重提高2.67kg,差异极显著(P<0.01);21日龄平均窝重增加12.70kg,差异极显著(P<0.01),公母猪达100kg体重日龄分别缩短17.14d和14.62d,体形外貌基本一致。     

杜长黑三元杂交商品猪生产性能观测

辽宁省昌图黑猪 (以下简称黑猪 )以适应性强 ,繁殖力高 ,肉味鲜香而闻名东北。经产母猪的窝产仔数可达 1 3 8头 ,且母性好 ,哺育能力强 ,非常适于小型养猪场及养猪户饲养 ,是较理想的杂交母本。 1 998年大兴安岭地区畜牧局从辽宁昌图县太平乡引进黑母猪6 4头 ,长黑二元母猪 2 4头 (长为加系长白 )。 6 4头黑猪引进后与从东北农大种猪场引进加系长白公猪进行杂交 ,所产仔猪留母作母本再与杜洛克公杂交生产三元杂交育肥肉猪 ,引进的 2 4头长黑母猪直接与杜洛克公杂交生产三元育肥肉猪。现将试验结果报告如下。1　材料与方法1 1　试验猪黑猪母…     

母猪背膘厚度对其繁殖性能的影响

此文研究分析大白、长白纯种母猪在配种时背膘厚度,经产母猪配种时背膘厚度与窝均产活仔数、初生窝重,哺乳期间背膘厚度减少与断奶窝重、断奶至发情时间间隔等指标之间的关系。结果表明,随着胎次的增加母猪配种时的背膘厚度呈下降趋势,第2胎母猪下降最明显;经产母猪配种时背膘厚度为12.5～18.0mm时,窝均产活仔数最高、初生窝重也最重;哺乳期间母猪背膘厚度减少与仔猪断奶窝重关系不明显,当背膘厚度减少3.0～6.0mm时,断奶至发情时间间隔最短(5.24±0.46)天。     

撒坝猪促卵泡素β亚基基因多态性及其与头胎产仔性能相关性研究

此文分析了促卵泡素(FSH)β亚基基因在撒坝猪群体中的多态性分布及其不同基因型与头胎产仔性能的相关性。结果表明,撒坝猪FSHβ亚基基因等位基因A及其基因型AA在群体中占优势,频率分别为0.8490和0.7604。FSHβ亚基基因在群体中处于哈迪-温伯格不平衡状态。乳头数以AA基因型最高,产仔数、产活仔数、初生窝重和45日龄窝重以AB基因型最高,BB基因型在所有分析性状上均表现最低,但3种基因型间的差异均不显著(P>0.05)。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.