The mammalian target of rapamycin pathway and its role in molecular nutrition regulation

Mammalian target of rapamycin (mTOR) is a protein serine-threonine kinase that functions as a central element in signaling pathway involved in control of cell growth and proliferation. mTOR exists in at least two distinct multi-protein complexes, mTORC1 and mTORC2. mTOR kinase controls the translation machinery, in response to nutrients and growth factors, via activation of p70 ribosomal S6 kinase and inhibition of eukaryotic initiation factor-4E-binding protein. In this report, we review the mTOR signaling pathway and its interaction with food intake, insulin resistance, lifespan and adipogenic regulation during the molecular nutrition regulation.     

Characterization of copper adsorption onto an alginate encapsulated magnetic sorbent by a combined FT-IR, XPS, and mathematical modeling study

Copper adsorption onto calcium alginate encapsulated magnetic sorbent is studied in this paper. The objective of this study was to qualitatively and quantitatively elucidate the copper binding onto the sorbent. The adsorption increases from around 0 to almost 100% as the initial pH is increased from 2 to 5. A maximum adsorption capacity of 0.99 mmol g(-1) is achieved. The FT-IR and XPS studies show that the C-O in carboxyl group of alginate directly attaches to the copper ion that leads to most of the adsorption. A mathematical model is developed, and it includes ion exchange between the calcium and the copper, coordination reaction between the functional group and the copper, as well as surface complex formation between the iron oxide and the copper. The model is capable of describing and predicting effects of various key operational parameters on the adsorption process, such as initial pH, metal concentration, and dosage of sorbent.     

Prevalence, antibiotic susceptibility, and virulence factors of Yersinia enterocolitica and related species from ready-to-eat vegetables available in Korea

A total of 673 ready-to-eat vegetable samples were collected in Korea from 2001 to 2002 and analyzed for the presence of Yersinia spp. We analyzed biotypes, serotypes, and susceptibility to 12 antibiotics and tested for virulence genes of pathogenic Yersinia enterocolitica isolates by PCR assay. Among the samples, 27 (4.0%) were found to be contaminated with Yersinia spp. Among the 27 strains of Yersinia spp. isolates, 18 strains (66.7%) of Y. enterocolitica, 5 strains (18.5%) of Y. frederiksenii, 3 strains (11.1%) of Y. intermedia, and 1 strain (3.7%) of Y. kristensenii were identified. According to the serotypes of Y. enterocolitica isolates, O:3 (11.1%) and O:5 (11.1%) were the most predominant, followed by O:8 (5.6%) and others (72.2%). For biotypes of Y. enterocolitica isolates, 1A (77.8%) was the most predominant, followed by 3B (11.1%), 3 (5.6%), and 5A (5.6%). Also, an antibiotic susceptibility test showed that Y. enterocolitica isolates were very susceptible to the antibiotics tested but highly resistant to ampicillin (94%), cephalothin (100%), and carbenicillin (83%). PCR assays with specific primers derived from yst and ail genes of Y. enterocolitica were applied to confirm the presence of pathogenic Y. enterocolitica. Among the 18 strains of Y. enterocolitica isolates, only 3 strains (O:3/1A, UT/3B, and UT/1A isolated from Chinese cabbage, onion, and spinach, respectively) were shown to have a virulence gene.     

Effects of moisture content and drying temperature on the physicochemical properties of ostrich jerky

The objective of this study was to investigate the influence of temperature (50, 60, and 70 degrees C) and moisture content (18, 21, and 24%) on the quality ofjerky products from ostrich meat. The jerky products were evaluated by physicochemical and sensory methods. The tensile strength of the samples prepared to 24% w.b. moisture content at 50 degrees C was lowest (p < 0.05; 124 N) while those prepared under other conditions were in the range of 208-268 N (p > 0.05). The water activity of the jerky products was 0.51-0.72, and significant influence of drying temperature on protein solubility was also observed, but the samples dried at the same temperature had similar levels of soluble protein (p > 0.05) regardless of moisture content of samples. The pH of the samples dried at 50 degrees C and 60 degrees C showed little change in different moisture content, but samples dried at 70 degrees C tended to affect the pH by moisture content. Hunter a-values showed a predominantly increasing trend in all moisture levels as the heating temperature increased. The jerky product prepared to 24% w.b. moisture content at 60 degrees C showed the best sensory overall acceptability.     

基于PubMLST数据库分析蜡样芽胞杆菌群的遗传学

以蜡样芽胞杆菌（Bacillus cereus）PubMLST数据库为数据来源,通过Phyloviz、Mega和IQ-tree软件研究蜡样芽胞杆菌群的遗 传学。 结果表明,筛选后得到1 329株完整的蜡样芽胞杆菌群的菌株信息,其中蜡样芽胞杆菌（B. cereus）及变种864株、苏云金芽胞杆 菌（Bacillus thuringiensis）及变种345株、炭疽芽胞杆菌（Bacillus anthracis）61株、韦氏芽胞杆菌（Bacillus weihenstephanensis）、蕈状芽胞杆 菌（Bacillus mycoides）、假蕈状芽胞杆菌（Bacillus pseudomycoides）分别为33、21和5株。 群内占比很高的蜡样芽胞杆菌和苏云金芽胞 杆菌具有丰富而复杂的遗传多样性,相互交织地散布于群内几乎所有的进化分支上,两者无法区分;炭疽芽胞杆菌在进化树上位于 相对独立而保守的一个分支;韦氏芽胞杆菌与蕈状芽胞杆菌虽然在菌落形态上差异很大,但两者在系统进化树上位于同一个分支, 同源性极高。     

The effect of boiling water on disinfection by-product exposure

Chloraminated and chlorinated waters containing bromide were used to determine the impact of boiling on disinfection by-product (DBP) concentrations. No significant changes were detected in the concentrations of the dihalogenated haloacetic acids (DXAAs) (i.e., dichloro-, bromochloro-, dibromoacetic acid) upon boiling of chloraminated water, whereas the levels of the trihalogenated haloacetic acids (TXAAs) (i.e., trichloro- (TCAA), bromodichloro- (BDCAA), dibromochloroacetic acid (DBCAA)) decreased over time (e.g., 9-37% for TCAA). Increased DXAA concentrations (58-68%) were detected in the boiled chlorinated sample, which likely resulted from residual chlorine reacting with DXAA precursors. TCAA concentration was unchanged after boiling chlorinated water for 1 min, but a 30% reduction was observed after 5 min of boiling. BDCAA concentrations decreased 57% upon boiling for 1 min and were completely removed after 2 min of boiling, whereas DBCAA was removed after boiling chlorinated water for 1 min. Trihalomethane concentrations were reduced in both chloraminated (74-98%) and chlorinated (64-98%) water upon boiling. Boiling chloraminated water for 1 min reduced chloroform concentration by 75%. Chloroform was reduced by only 34% in chlorinated water after a 1 min boil, which indicates that simultaneous formation and volatilization of chloroform was occurring. Most of the remaining DBPs (e.g. haloketones, chloral hydrate, haloacetonitriles) were removed by at least 90% after 1 min of boiling in both samples. These data suggest that other mechanisms (e.g., hydrolysis) may have been responsible for removal of the non-volatile DBPs and further highlight the importance of examining individual species when estimating thermal effects on DBP concentrations.     

广东省茂名市开通建设工程评标专家语音通知系统

为切实创造建设工程招投标公开、公正、公平的竞争环境,进一步强化评标专家抽取产生具体操作过程的保密性。提高评标质量,确保公正性．茂名市建设局组织开发了“建设工程评标专家语音通知系统”并于5月14日正式开通。     

lordif: An R Package for Detecting Differential Item Functioning Using Iterative Hybrid Ordinal Logistic Regression/Item Response Theory and Monte Carlo Simulations

Logistic regression provides a flexible framework for detecting various types of differential item functioning (DIF). Previous efforts extended the framework by using item response theory (IRT) based trait scores, and by employing an iterative process using group-specific item parameters to account for DIF in the trait scores, analogous to purification approaches used in other DIF detection frameworks. The current investigation advances the technique by developing a computational platform integrating both statistical and IRT procedures into a single program. Furthermore, a Monte Carlo simulation approach was incorporated to derive empirical criteria for various DIF statistics and effect size measures. For purposes of illustration, the procedure was applied to data from a questionnaire of anxiety symptoms for detecting DIF associated with age from the Patient-Reported Outcomes Measurement Information System.