A Comparison of Anonymous E-Peer Review Versus Identifiable E-Peer Review on College Student Writing Performance and Learning Satisfaction

The purpose of this study was to compare the effects of anonymous e-peer review with identifiable e-peer review on student writing performance and learning satisfaction. It also investigated whether anonymous e-peer review facilitated a greater amount of critical peer feedback. Quasi-experimental design was used to test group differences on the dependent variables. Participants were 48 freshmen enrolled in two English Composition classes at Old Dominion University in the fall semester of 2003. The two intact classes taught by the same instructor were randomly assigned to the anonymous e-peer review group and the identifiable e-peer review group. The results showed that students in the anonymous e-peer review group outperformed their counterparts in the identifiable e-peer review group on writing performance; students in the anonymous e-peer review group provided a greater amount of critical feedback and lower ratings on their peers\u27 writing. No significant differences between the anonymous e-peer review group and the identifiable e-peer review group were found on student learning satisfaction

A Comparison of Anonymous Versus Identifiable E-Peer Review On College Student Writing Performance and the Extent of Critical Feedback

Peer review has become commonplace in composition courses and is increasingly employed in the context of telecommunication technology. The purpose of this experiment was to compare the effects of anonymous and identifiable electronic peer (e-peer) review on college student writing performance and the extent of critical peer feedback. Participants were 92 undergraduate freshmen in four English composition classes enrolled in the fall semesters of 2003 and 2004. The same instructor taught all four classes, and in each semester, one class was assigned to the anonymous e-peer review group and the other to the identifiable e-peer review group. All other elements—course content, assignments, demands, and classroom instruction— were held constant. The results from both semesters showed that students participating in anonymous e-peer review performed better on the writing performance task and provided more critical feedback to their peers than did students participating in the identifiable e-peer review

A Fuzzy Social Network Analysis Method and a Case Study on Tianya Tourism Forum in China

Abstract. Social networking service (SNS) has become online service platforms that focus on facilitating the building of social networks among people who share interests, activities, backgrounds or real-life connections, and has had a rapid development in China in the past few years. This paper aims to develop a fuzzy social network service analysis method, which combines graph-theory with related fuzzy approach, to analyze the social network structural features and the distribution characteristics of interpersonal nodes in SNS community. A case study on a very famous Chinese tourism BBS -Tianya is conducted to illustrate and validate the proposed approach. The research findings are: 1) the attraction degrees of various areas in the forum are significantly different; 2) interpersonal nodes in the forum are concentrated relatively; 3) the fuzzy out-degrees and the fuzzy indegrees of interpersonal nodes in the forum conflict with each other; 4) the distribution of interpersonal nodes is influenced by geographical relations. These findings can directly support social network service management and particularly tourism online service developments

The modulation of acute methamphetamine on the neuronal network oscillations in rat hippocampal CA3 area.

Gamma frequency oscillations (γ, 30–100 Hz) have been suggested to underlie various cognitive and motor functions. The psychotomimetic drug methamphetamine (MA) enhances brain γ oscillations associated with changes in psychomotor state. Little is known about the cellular mechanisms of MA modulation on γ oscillations. We explored the effects of multiple intracellular kinases on MA modulation of γ induced by kainate in area CA3 of rat ventral hippocampal slices. We found that dopamine receptor type 1 and 2 (DR1 and DR2) antagonists, the serine/threonine kinase PKB/Akt inhibitor and N-methyl-D-aspartate receptor (NMDAR) antagonists prevented the enhancing effect of MA on γ oscillations, whereas none of them affected baseline γ strength. Protein kinase A, phosphoinositide 3-kinase and extracellular signal-related kinases inhibitors had no effect on MA. We propose that the DR1/DR2-Akt-NMDAR pathway plays a critical role for the MA enhancement of γ oscillations. Our study provides an new insight into the mechanisms of acute MA on MA-induced psychosis

Acute Ethanol Inhibition of γ Oscillations Is Mediated by Akt and GSK3β

Hippocampal network oscillations at gamma band frequency (γ, 30–80 Hz) are closely associated with higher brain functions such as learning and memory. Acute ethanol exposure at intoxicating concentrations (≥50 mM) impairs cognitive function. This study aimed to determine the effects and the mechanisms of acute ethanol exposure on γ oscillations in an in vitro model. Ethanol (25–100 mM) suppressed kainate-induced γ oscillations in CA3 area of the rat hippocampal slices, in a concentration-dependent, reversible manner. The ethanol-induced suppression was reduced by the D1R antagonist SCH23390 or the PKA inhibitor H89, was prevented by the Akt inhibitor triciribine or the GSk3β inhibitor SB415286, was enhanced by the NMDA receptor antagonist D-AP5, but was not affected by the MAPK inhibitor U0126 or PI3K inhibitor wortmanin. Our results indicate that the intracellular kinases Akt and GSk3β play a critical role in the ethanol-induced suppression of γ oscillations and reveal new cellular pathways involved in the ethanol-induced cognitive impairment

YdfD, a Lysis Protein of the Qin Prophage, Is a Specific Inhibitor of the IspG-Catalyzed Step in the MEP Pathway of Escherichia coli

Bacterial cryptic prophage (defective prophage) genes are known to drastically influence host physiology, such as causing cell growth arrest or lysis, upon expression. Many phages encode lytic proteins to destroy the cell envelope. As natural antibiotics, only a few lysis target proteins were identified. ydfD is a lytic gene from the Qin cryptic prophage that encodes a 63-amino-acid protein, the ectopic expression of which in Escherichia coli can cause nearly complete cell lysis rapidly. The bacterial 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway is responsible for synthesizing the isoprenoids uniquely required for sustaining bacterial growth. In this study, we provide evidence that YdfD can interact with IspG, a key enzyme involved in the MEP pathway, both in vivo and in vitro. We show that intact YdfD is required for the interaction with IspG to perform its lysis function and that the mRNA levels of ydfD increase significantly under certain stress conditions. Crucially, the cell lysis induced by YdfD can be abolished by the overexpression of ispG or the complementation of the IspG enzyme catalysis product methylerythritol 2,4-cyclodiphosphate. We propose that YdfD from the Qin cryptic prophage inhibits IspG to block the MEP pathway, leading to a compromised cell membrane and cell wall biosynthesis and eventual cell lysis

Effect of Heat-Moisture Treatments on Digestibility and Physicochemical Property of Whole Quinoa Flour

The starch digestion processing of whole grain foods is associated with its health benefits in improving insulin resistance. This study modified the digestibility of whole quinoa flour (WQ) via heat-moisture treatment (HMT), HMT combined with pullulanase (HMT+P), HMT combined with microwave (HMT+M), and HMT combined with citric acids (HMT+A), respectively. Results showed that all the treatments significantly increased (p < 0.05) the total dietary fiber (TDF) content, amylose content, and resistant starch (RS) content, however, significantly decreased (p < 0.05) the amylopectin content and rapidly digestible starch (RDS) content of WQ. HMT+P brought the highest TDF content (15.3%), amylose content (31.24%), and RS content (15.71%), and the lowest amylopecyin content (30.02%) and RDS content (23.65%). HMT+M brought the highest slowly digestible starch (SDS) content (25.09%). The estimated glycemic index (eGI) was respectively reduced from 74.36 to 70.59, 65.87, 69.79, and 69.12 by HMT, HMT+P, HMT+M, and HMT+A. Moreover, a significant and consistent reduction in the heat enthalpy (ΔH) of WQ was observed (p < 0.05), after four treatments. All these effects were caused by changes in the starch structure, as evidenced by the observed conjunction of protein and starch by a confocal laser scanning microscope (CLSM), the decrease in relative crystallinity, and transformation of starch crystal

An Improved Whole-Blood Gamma Interferon Assay Based on the CFP21-MPT64 Fusion Protein▿

Differentiation of latent tuberculosis infection (LTBI) from a healthy, unexposed population plays a vital role in the strategy of controlling and eliminating tuberculosis (TB). Both CFP21 and MPT64, antigens encoded by the RD2 region which are restricted in the Mycobacterium tuberculosis complex, are TB-specific diagnostic candidate antigens. In this study, we designed a fusion protein by linking both CFP21 and MPT64 with a 15-amino-acid peptide, (G4S1)3, and overexpressed the fusion protein in Escherichia coli. A new whole-blood gamma interferon assay based on the recombinant fusion protein, CFP21-MPT64 (rCM-WBIA), was developed and compared with the tuberculin skin test (TST) for screening of LTBI in household contacts of patients with sputum-positive TB. rCM-WBIA had a slightly higher sensitivity (66.7%; 24/36 contacts) than that of the TST (61.1%; 22/36 contacts) for household contacts. We found that rCM-WBIA had a very high sensitivity (90.9%) and specificity (71.4%) for LTBI detection compared with TST. The overall agreement between rCM-WBIA and TST was 83.3% (k = 0.64); rCM-WBIA positivity was associated with a larger TST induration. These results suggest that rCM-WBIA, based on the recombinant fusion protein CFP21-MPT64, is a promising alternative diagnostic tool for detection of LTBI

Immunogenicity and Protective Efficacy of a Novel Recombinant BCG Strain Overexpressing Antigens Ag85A and Ag85B

Recombinant Bacillus Calmette-Guérin (rBCG) strain is the promising vaccine candidate for tuberculosis (TB) prevention, which aims at providing more enduring and enhanced protection than the parental BCG vaccine. In this study, three rBCG strains overexpressing immunodominant antigens Ag85B (rBCG::85B), Ag85A (rBCG::85A), or both (rBCG::AB) of Mycobacterium tuberculosis were constructed, respectively. rBCG strains showed higher level of overexpression of Ag85A and/or Ag85B proteins than BCG containing empty vector pMV261(rBCG::261), which had low levels of endogenous expression of both proteins as expected. rBCG::AB strain could provide the strongest short-term and long-term protection in the lung against intravenous infection with virulent M. tuberculosis than rBCG::261 control and other two rBCG strains overexpressing single antigen. The stronger and longer-lasting protection provided by rBCG::AB than rBCG::261 was correlated with systemic in vitro antigen-specific IFN-γ responses. Therefore, our results indicate that rBCG::AB could be a very promising TB vaccine candidate and should be further evaluated for the preclinical test