A Novel Proof based on the method of infinite descent for Fermat’s Last Theorem

Fermat’s Last Theorem is that for each  k >=3  (k is an integer), the equation  involving x, y and z has no positive integer solution. This paper proposed a novel proof for the Fermat’s last theorem by the methods of infinite descent and complex variable analysis

The sunflower moth, Homoeosoma nebulella (Denis et Schiffermüller ) (Lepidoptera: Pyralidae): outbreaks and pest management in Linhe, Inner Mongolia 2007–2008

Sunflowermoth Homoeosoma nebulella is the most common pest of sunflowers (Helianthus annuus L.) in China. A large outbreak involving H. nebulella was discovered in Linhe of the Mongolia Autonomous Region in 2007. Different issues related to pest management were investigated in 2007–2008. Irrigation for overwintering could promote pest outbreak in the following year. It is the safest practice to sow from mid-May to mid-June, i.e. not too early. The quantity of larvae could be reduced by the treatment with Bacillus thuringiensis. The effective pest management should include selecting proper sowing date, non-irrigation and B. thuringiensis treatment. Sex pheromone trapping as a potential control measure requires further studies

Genomic homogeneity between Mycobacterium avium subsp. avium and Mycobacterium avium subsp. paratuberculosis belies their divergent growth rates

BACKGROUND: Mycobacterium avium subspecies avium (M. avium) is frequently encountered in the environment, but also causes infections in animals and immunocompromised patients. In contrast, Mycobacterium avium subspecies paratuberculosis (M. paratuberculosis) is a slow-growing organism that is the causative agent of Johne's disease in cattle and chronic granulomatous infections in a variety of other ruminant hosts. Yet we show that despite their divergent phenotypes and the diseases they present, the genomes of M. avium and M. paratuberculosis share greater than 97% nucleotide identity over large (25 kb) genomic regions analyzed in this study. RESULTS: To characterize genome similarity between these two subspecies as well as attempt to understand their different growth rates, we designed oligonucleotide primers from M. avium sequence to amplify 15 minimally overlapping fragments of M. paratuberculosis genomic DNA encompassing the chromosomal origin of replication. These strategies resulted in the successful amplification and sequencing of a contiguous 11-kb fragment containing the putative Mycobacterium paratuberculosis origin of replication (oriC). This fragment contained 11 predicted open reading frames that showed a conserved gene order in the oriC locus when compared with several other Gram-positive bacteria. In addition, a GC skew analysis identified the origin of chromosomal replication which lies between the genes dnaA and dnaN. The presence of multiple DnaA boxes and the ATP-binding site in dnaA were also found in M. paratuberculosis. The strong nucleotide identity of M. avium and M. paratuberculosis in the region surrounding the origin of chromosomal replication led us to compare other areas of these genomes. A DNA homology matrix of 2 million nucleotides from each genome revealed strong synteny with only a few sequences present in one genome but absent in the other. Finally, the 16s rRNA gene from these two subspecies is 100% identical. CONCLUSIONS: We present for the first time, a description of the oriC region in M. paratuberculosis. In addition, genomic comparisons between these two mycobacterial subspecies suggest that differences in the oriC region may not be significant enough to account for the diverse bacterial replication rates. Finally, the few genetic differences present outside the origin of chromosomal replication in each genome may be responsible for the diverse growth rates or phenotypes observed between the avium and paratuberculosis subspecies

Mapping of the methylation pattern of the hMSH2 promoter in colon cancer, using bisulfite genomic sequencing

The detailed methylation status of CpG sites in the promoter region of hMSH2 gene has yet not to be reported. We have mapped the complete methylation status of the hMSH2 promoter, a region that contains 75 CpG sites, using bisulfite genomic sequencing in 60 primary colorectal cancers. And the expression of hMSH2 was detected by immunohistochemistry. The hypermethylation of hMSH2 was detected in 18.33% (11/60) of tumor tissues. The protein of hMSH2 was detected in 41.67% (25/60) of tumor tissues. No hypermethylation of hMSH2 was detected in normal tissues. The protein of hMSH2 was detected in all normal tissues. Our study demonstrated that hMSH2 hypermethylation and protein expression were associated with the development of colorectal cancer

脑卒中后遗症期患者社区康复评定量表选择初探

Objective: To choose the scales that can comprehensively assess the function of patients with stroke sequelae for the grassroots medical staff. Methods: The commonly used scales were selected. The patients with stroke sequelae were assessed by the MOS item short from health survey(SF-36), Modified Barthel Index(MBI), Brain Injury Community Rehabilitation Outcome Scales(BICRO-39)，WHO Disability Assessment Scale II(WHO-DAS II) and Anxiety and Depression Self-rating Scales(SAS and SDS). The assessment datum was conducted by Pearson correlation coefficient. Results: The data of MBI have significant correlation among the datum of WHO-DASII, SF-36 and BICRO 39 scales(P<0.05). The datum of MBI doesn’t have correlation among the datum of the SAS and SDS (P>0.05). Conclusions: Community doctors can choose MBI which can effectively assess the activities of daily living for the community patients with stroke sequelae. MBI also can reflect the functional levels of community patients with stroke sequelae.目的：为基层医务人员选择综合科学评价脑卒中后遗症期患者的功能水平的量表。方法：选择常用的量表：简明健康状况调查表SF-36量表、改良Barthel指数评分标准、脑损伤社区康复结果量表(BICRO-39 scales)、世界卫生组织残疾评定量表（WHODASII）、焦虑抑郁自评量表（SAS & SDS）在内的六个量表的数据采集，分别与改良Barthel指数评分标准进行皮尔森相关系数（Pearson correlation coefficient）分析。结果：BI的测评结果与WHODAS II、SF-36、BICRO-39的测评结果显著相关（P值<0.05）；而与SAS及SDS的测评结果不相关（P>0.05）。结论：基层医生可以选择BI量表对脑卒中后遗症患者的日常生活活动能力进行评定；BI量表也可以进一步反映脑卒中后遗症患者的功能水平