关于有限群极大子群的CI-截和Deskins完备的一个注记

设G是有限群，M是G的极大子群．令K／N是G的一个主因子，K≤M而N（2=M，称MnN／K为M的一个CI-截，M的所有CI-截都同构．M在G中的一个完备是G的一个子群C，如果C（z=M，而C的每个G不变真子群都在M中．应用这些概念，本文得到了有关有限群可解性的新结论．     

有限群的弱m-正规子群

定义了有限群G的弱m-正规子群,并在此定义下,赋予有限群的子群的诸多性质,得出(1)若G的Sylow-子群在G中弱m-正规,且至少有一个Sylow-子群在G的极大子群M中正规,则M为可解群.(2)若有限群G的Sylow-子群都是弱m-正规的,且在G的极大子群M中没有正规的Sylow-子群,则M是非可解的.(3)设有限群G的Sylow-子群都是弱m-正规的,G的极大子群M可解的充分必要条件是至少有一个Sylow-子群在M中正规.(4)若G的Sylow-子群都在G中弱m-正规,且至少有一个Sylow-子群在G的极大子群M中正规,M至少有3个不同的素因子,则G可解.(5)设M为G的任一极大子群,且M为可解群.若M的每个Sylow-子群非循环且它们的极大子群都在G中弱m-正规,则G可解.     

有限群p-可解的几个充分条件

子群的中心化子对群的结构有很强的控制作用.对有限群G的极小子群的中心化子赋予较弱的条件,得到G的p-可解的充分条件.在一定程度推广了李世荣的结果.     

极小子群的中心化子与群的p-可解性

得到G为p-可解的一些充分条件.设p是一个固定的奇素因子,如果对G的每个p阶子群X,或X(?)G,或|G:C_G(X)|为素数的方幂.则G是p-可解.从而推广了李世荣的一个定理.     

一类拟正则半群的性质和特征

定义了一类拟正则半群,即拟右半群.利用拟正则半群和左中心幂等元的性质,证明了S为拟右半群时,(1)S为拟完全正则半群;(2)RegS为完全正则半群;(3)R*为S上的最小半格同余;(4)RegS上的每个R-类Tα为右群;(5)TαGα×Eα,其中Gα为群,Eα为右零半群.在此基础上得到了3个等价命题:若S为具有左中心幂等元半群,则(1)S为拟右半群;(2)S为拟完全正则的,RegS为S的理想;(3)S为右群强半格的诣零理想扩张.     

幂等半群与拟商群

文献[1]首次研究了超群(一个群的幂半群P(G)的子群),文献[2]专门讨论了一类特殊的超群,称之为拟商群,其中要求单位元E为幺半群。本文在更弱的条件下研究超群,特别是拟商群。将幺半群降低为幂等半群(它有介子子半群和幺半群的结构),同样可以得到[2]中的大部分结论。此外,本文还讨论了幂等半群的性质以及拟商群的同态问题。     

两类半群的整体决定性

证明两类半群G0和G’都是整体决定的．设G是群,P是G的单位元．记GO—GU{0}为由G添加一个零元0所得的半群,即G0是0一群．记G’=GU（1）为由G另外添加了一个幺元1所得的半群,注意1≠e,且1是半群G’的幺元．设Go为由所有G0所构成的半群类和G1为由所有G’所构成的半群类．     

AHX群

HX群是一个群的幂集上的群结构.本文将HX群推广到一类特殊的格——原子格上,称之为AHX群.HX群的结论大部分能在原子格上实现.商群与拟商群提升到格上以后,得到较为一般化的结论.最后讨论了几个基本的同态定理.     

自同构群的阶为26p2的有限Abel群

设p是奇素数,G是有限Abel群,A(G)是G的自同构群.运用初等数论方法证明了:当| A(G)|=26p2时,如果p≠3,5或17,则G至多有20种类型.     

一类非迷向Heisenberg群上凸函数的两类比较原理

在一类非迷向Heisenberg群上引入凸函数概念，通过证明零-拉格朗日性质，并用积分估计的方法给出该群上Monge-Ampere型次椭圆算子的比较原理以及非散度型次椭圆算子在锥形区域上的比较原理．     

Permutation tests: are there differences in product liking?

The target of our considerations is whether or not we can find significant differences between subgroups of consumers with respect to given hedonic variables. For this purpose a STATIS-consensus is computed for each group and the dissimilarities between groups are judged with the help of the RV-coefficient. Since the distribution of this coefficient is unknown and we do not make any assumptions on the distribution of the error terms, a permutation test is performed. This provides a simple possibility to test for significance of the dissimilarities in question. Some pre-treatment of the data is necessary to perform this statistical test. Afterwards subgroups according to the two sets of consumer tests, the different geographies and some of the classification variables within consumer test 1 are considered. When significant dissimilarities are found, a graphical representation of the respective consensuses is provided to interpret the differences.     

Familiarity influences social networks in dairy cows after regrouping

Regrouping is common practice when managing dairy cow groups, and it is known to have disruptive effects on behavior and production. The presence of a small group of familiar cows upon regrouping may provide social support and mitigate some of the negative effects. In this study we investigated (1) how regrouping affects social relationships among familiar cows and (2) if cows prefer familiar individuals over unfamiliar ones as social partners after regrouping. We used 3 established groups of cows to create 2 new groups, each containing 14 cows, using subgroups of familiar animals (i.e., 4, 6, and 4 cows) from the original groups. The new groups were similar in respect to the age, parity, and sire of cows. The frequencies of grooming and displacements were determined in the walking alley, lying stalls, and feed bunk by observing 48 h of continuous video before regrouping, directly after regrouping, and 1 wk later. First, social network analysis was applied to investigate the effects of regrouping on the relationships within the subgroups of familiar cows. Second, we determined if familiar cows were more or less connected than would be expected by chance (i.e., assortment), considering displacement, grooming, and feed bunk neighbor networks (derived from electronic feeder data) after regrouping. Regrouping increased the number of displacements, especially in the walking alley. Within the subgroups of familiar cows, regrouping resulted in slightly more displacements, but the network structure did not change. The frequency of grooming among familiar cows remained stable across all observation periods, and the network structure was not affected by regrouping. We found positive assortment in grooming and feed bunk neighbor networks, thereby suggesting that cows preferred familiar individuals as grooming partners and feeding neighbors directly after regrouping and, to a smaller extent, 1 wk later. The effect of familiarity on displacements depended on the pen area. The weak assortment directly after regrouping at the feed bunk indicated that familiar cows displaced each other more than unfamiliar ones, possibly because they were neighbors more often. Our results indicated that a small group of familiar cows may provide ongoing social buffering after regrouping. Further research with multiple groups and larger group sizes is needed to determine whether similar effects are consistently present when groups of familiar cows are subjected to regrouping.     

魔芋葡甘聚糖-可得然胶共混凝胶替代动物脂肪对乳化肠品质特性的影响

为探究魔芋葡甘聚糖（konjac glucomannan,KGM）和可得然胶（curdran gum,CUD）的添加对猪肉乳化肠品质特性的影响,采用KGM-CUD共混凝胶代替乳化肠中质量分数依次为0%（G1组,对照组）、33%（G2组）、66%（G3组）以及100%（G4组）的猪背膘,研究KGM-CUD共混凝胶对猪肉乳化肠蒸煮损失、色差、持水性、质构特性和脂质氧化的影响,并进行感官评价。结果表明：当KGM-CUD共混凝胶质量分数为0.3%,且KGM∶CUD=8∶2（m/m）时,KGM-CUD共混凝胶乳化效果最佳。与对照组G1组相比,G2组和G3组蒸煮损失显著降低（P＜0.05）,持水性无显著差异（P＞0.05）;G2组红度值显著上升（P＜0.05）;G3组红度值和硬度显著上升（P＜0.05）。随着替代比例的上升,乳化肠抗氧化能力逐渐增强,G2组和G3组微观结构与对照组相比无显著差异,但G4组存在明显空隙,且总体可接受度略有降低。结果表明,用0.3%的KGM-CUD共混凝胶（KGM∶CUD=8∶2）替代乳化肠66%的脂肪时,能提高乳化肠的营养价值和产品质量,显著延长保藏期。     

不同腌制方式对扬州盐水鹅预制品品质的影响

为改进盐水鹅预制品的品质,试验设置以下处理组:滚揉超声复合腌制法(G+C处理组)、滚揉腌制法(G处理组)、超声腌制法(C处理组)、加盐滚揉腌制法(G+NaCl处理组)和常规湿腌法(常规处理组),以肉色、持水力、脂肪氧化值、质构、感官评价、微观结构、脂肪酸等为评价指标,探究超声处理、滚揉处理对盐水鹅预制品品质的影响。结果表明:G+NaCl处理组的肉色鲜亮,持水力最好。常规处理组TBARS值最低,经过滚揉、超声处理的其他处理组的脂肪氧化程度均高于常规处理组。感官评价及质构结果表明G+NaCl处理组的弹性和咀嚼性为最佳。各处理组共检测出8种脂肪酸,饱和脂肪酸(SFA)2种、不饱和脂肪酸(UFA)6种;单不饱和脂肪酸(MUFA)和多不饱和脂肪酸(PUFA)各为3种。其中C处理组、G+NaCl处理组和G+C处理组的脂肪酸总量相近,且G+C的脂肪酸总量最小。综上,G+NaCl处理组是最优组。     

Bacteriocin-producing Lactobacillus strains isolated from poto poto, a Congolese fermented maize product, and genetic fingerprinting of their plantaricin operons

Thirty one bacteriocin-producing Lactobacillus isolates were identified among 135 lactobacilli isolated from the Congolese fermented maize product poto poto, during the preparation and from the finished product. Using species-specific PCR and 16S rRNA gene sequencing, 28 and 3 isolates were identified as L. plantarum and L. fermentum, respectively. Cluster analysis of RAPD-PCR fingerprints revealed two main groups (G1 and G2) plus the L. fermentum isolate C4-13. Group G1 contained 23 isolates with a similarity coefficient >74.5%, and could be divided in two subgroups (G1-1, G1-2) each with several branches, plus the L. plantarum isolate C11. Group G2 contained 8 isolates with a similarity coefficient >86%, with two main branches. Using PCR amplification with specific primers, several genes of the plantaricin cluster found in L. plantarum C11 were identified in the isolates. The number of genes that were detected varied between the strains. The L. fermentum isolate EC11 also contained the plnDEFG genes. PCR amplification of DNA from isolates with primers directed to the upstream and downstream region of the plantaricin cluster generated an amplicon identical to that obtained with DNA from the control strain L. plantarum WCFS1. Amplification products from the positive strains were used for restriction analysis with HindIII, EcoRI and KpnI in separate reactions. Cluster analysis of restriction profiles revealed high similarities for EcoRI and HindII digest profiles, and an identical profile for all KpnI digests. The L. fermentum EC11 isolate clustered with L. plantarum strains in a group with a high correlation coefficient. The results suggest a low degree of diversity in the plantarincin gene cluster. However, other strains that tested positive for individual plantaricin genes may present great heterogeneity in the plantaricin operons. Because of their broad spectra of inhibition (including Escherichia coli, Salmonella enterica, Enterobacter aerogenes, Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, and Enterococcus faecalis), isolates from the present study could be used to improve the safety and storage stability of poto poto.     

Yacon (Smallanthus sonchifolius) and Lactobacillus acidophilus CRL 1014 reduce the early phases of colon carcinogenesis in male Wistar rats

The modifying effects of aqueous yacon extract (AYE) and Lactobacillus acidophilus CRL 1014 against colon carcinogenesis induced by 1,2-dimethylhydrazine (DMH) in male Wistar rats were investigated. Animals were allocated into five groups: G1: untreated group; G2: DMH-treated group; G3: DMH + L. acidophilus-treated group; G4: DMH + AYE-treated group; G5: DMH + L. acidophilus and AYE-treated group. A significant reduction (p < 0.05) in leukocyte DNA damage and in colonic cell proliferation was observed after the first DMH administration in G3 (probiotic), G4 (prebiotic) and G5 (synbiotic) groups. In this moment, a significant increase (p < 0.05) in colonic apoptosis was also observed in G3 (probiotic) and G5 (synbiotic) groups. In special, at five months after DMH administrations, a significant reduction (p < 0.05) in ACF development was observed in G3 (probiotic), G4 (prebiotic) and G5 (synbiotic) groups. Incidence of colon tumors was lower at five months in G4 (prebiotic) and G5 (synbiotic) groups but not in eight months after DMH administrations. In conclusion, the findings suggest that the oral treatments have potential effects as a chemopreventive agent against colon carcinogenesis on an early stage of tumor development.