Recruitment of HIV-1 envelope occurs subsequent to lipid mixing: a fluorescence microscopic evidence

Entry of the human immunodeficiency virus (HIV) into the target cell is initiated by fusion with the cell membrane, mediated through the envelope glycoproteins gp120 and gp41, following engagement to CD4 and the co-receptor. Previous fusion kinetics studies on the HXB2 envelope protein (Env) revealed that Env recruitment occurred at about 13 min concurrent with the lipid mixing. To resolve the temporal sequence of lipid mixing and recruitment, we employed an inhibitory assay monitored by fluorescence microscopy using a gp41 ectodomain (gp41e) fragment, which blocked Env recruitment in stark contrast to the lack of gp41e effect on the lipid mixing. In addition, to demonstrate the mode of action for the inhibition of gp41e, our results strongly suggested that lipid mixing precedes the Env recruitment because lipid mixing can proceed with Env recruitment inhibited by exogeneous gp41e molecules. Importantly, it was found that the random clustering of Env molecules on the membrane surface occurred at ~1 minute whereas the Env recruitment was observed at 13 minutes after the attachment of Env-expressing cell to the target cell. This > 10-fold temporal discrepancy highlights that the productive assembly of Env molecules leading to fusion requires spatio-temporal coordination of several adjacent Env trimers aggregated via directed movement

The development and confirmatory factor analysis of the Service-Learning Reflection Scale for undergraduates

The purpose of this study is to develop and to examine the construct validity of the service-learning reflection scale for undergraduates based on Kolb\u27s learning theory. The research aims to: (1) recognize undergraduates\u27 levels of reflection for service-learning; (2) let undergraduates understand their learning styles; (3) evaluate the effect of service-learning for the instructors. We used the Likert\u27s style to make the scales. There are 33 items in the initial scale divided into four subscales inclusive of the concrete experience (CE), the reflection observation (RO), the abstract conceptualization (AC), and the active experience (AE). For the very first time, we invite four experts to evaluate all the items to proceed three times Delphi technique process. We adopt the item analysis, exploratory factor analysis and reliability analysis via 326 participants in the pretest. Cronbach\u27s alpha reliability coefficients of the four subscales are from .80 to .87, and that of the total scale was .95. The whole explained variance was 60.16%. In this study, we make use of the stratified sampling, 1,251 undergraduates, to analyze the construct validity by the confirmatory factor analysis. The model index such as GFI, AGFI, NFI, RFI, IFI and CFI are above .90, RMSEA and RMR are below .05, as well as PGFI and PNFI are above .50. In addition, the structural equation modeling analysis indicates measurement weights, measurement intercepts, structural covariance matrixes and measurement residuals of male/female and general/technical undergraduates groups are no significant differences. Moreover, the Cronbach\u27s alpha values of the four subscales are from .85 to .86, and that of the total scale is .95. The results show that the CFA and reliability analysis confirm the theoretical structure as well

The Non-linear Relationship between Muscle Voluntary Activation Level and Voluntary Force Measured by the Interpolated Twitch Technique

Interpolated twitch technique (ITT) is a non-invasive method for assessing the completeness of muscle activation in clinical settings. Voluntary activation level (VA), measured by ITT and estimated by a conventional linear model, was reported to have a non-linear relationship with true voluntary contraction force at higher activation levels. The relationship needs to be further clarified for the correct use by clinicians and researchers. This study was to established a modified voluntary activation (modified VA) and define a valid range by fitting a non-linear logistic growth model. Eight healthy male adults participated in this study. Each subject performed three sets of voluntary isometric ankle plantar flexions at 20, 40, 60, 80 and 100% maximal voluntary contraction (MVC) with real-time feedback on a computer screen. A supramaximal electrical stimulation was applied on tibia nerve at rest and during contractions. The estimated VA was calculated for each contraction. The relationship between the estimated VA and the actual voluntary contraction force was fitted by a logistic growth model. The result showed that according to the upper and lower limit points of the logistic curve, the valid range was between the 95.16% and 10.55% MVC. The modified VA estimated by this logistic growth model demonstrated less error than the conventional model. This study provided a transfer function for the voluntary activation level and defined the valid range which would provide useful information in clinical applications

Aqua­(4-fluoro­benzoato-κO)bis­(1,10-phenanthroline-κ2 N,N′)manganese(II) 4-fluoro­benzoate trihydrate

In the title compound, [Mn(C7H4FO2)(C12H8N2)2(H2O)](C7H4FO2)·3H2O, the MnII atom is coordinated by four N atoms from two chelating 1,10-phenanthroline ligands and two O atoms from one monodentate 4-fluoro­benzoate ion and one water mol­ecule, forming a distorted octa­hedral geometry. In the crystal, the three components are assembled into a tape structure along the a axis by O—H⋯O and C—H⋯O hydrogen bonds. Between the tapes, a π–π inter­action with a centroid–centroid distance of 3.569 (3) Å and a weak C—H⋯F hydrogen bond are observed

運用意識提升英語文法教學於國小外語：文法學習之效益研究

This study investigated the effects of consciousness-raising grammar teaching on EFL 6th graders’ learning of the English future tense as well as the participants’ opinions about consciousness-raising grammar teaching activities. Forty 6th graders, 20 in the high-level group and 20 in the low-level group, participated in the study for 8 weeks, twice a week, receiving consciousness-raising grammar teaching with the same activities. Pre-test and post-test were administered before and after the instruction. A questionnaire concerning consciousness-raising grammar teaching was distributed to gain the participants’ views about the activities. Paired sample t test and independent sample t test were used for analysis. The results showed that both high- and low-achievers’ performance in the posttest as compared to that in the pretest reached statistical significance. The low-achievers made even more progress than high-achievers; nevertheless, no claim can be made that conscious-raising grammar tasks are more effective for the performance of the low-achievers than the high achievers. Moreover, the participants had positive opinions about consciousness-raising tasks. The findings are in line with the previous studies (Ellis & Fotos, 1991; Fotos, 1993; Hu, 2008; Wang, 2008; Yip, 1994) concering the effecs of consciousness-raising activities.本研究探究意識提升文法教學對臺灣小六生英語未來式句型的學習成效。研究問題為：一，意識提升文法教學對高、低分組學生何者的學習成效較佳？二，研究對象對意識提升文法教學活動之看法為何？ 研究者對北市公立國小62位小六生施以劍橋兒童英語測驗，將分數在前、後各33%者，選為高分組及低分組，各20人。進行八週，每週兩次意識提升文法教學。以前、後測檢驗其對目標句型的熟悉程度。實驗教學後，以問卷調查研究對象對教學活動看法。 結果顯示，各組前、後測成績比較皆達顯著差異，且低分組進步幅度明顯多於高分組，但無法斷言意識提升文法教學活動對低分組有較佳成效。研究對象肯定意識提升文法教學活動。據此，研究者提出教學及研究建議

Does the Nurse-Led Case Management Benefit Rheumatoid Arthritis Patients in Reducing Distressing Symptoms and C-Reactive Protein: a 2-Year Follow-Up Study in Taiwan

Background: Rheumatoid arthritis (RA) is a chronic disease and may worsen over time. Today, nurse-led case management (NLCM) has been recommended to improve clinical outcomes for chronic disease patients, yet little is known regarding its impact on pain, fatigue, and C-reactive protein (CRP) among RA patients. We aimed to explore this issue among such groups via a two-group pre- and post-test approach. Methods: All subjects were recruited from one hospital in Taiwan from January 2017 to June 2018 and assigned to either a 6-month NLCM program in addition to usual care or to a control group that received usual care only. All of them were followed for 2 years. Outcomes of interests were compared at four time points: baseline, the third day after NLCM completion, and at 6 and 24 months after NLCM. Effects between them were tested using the generalized estimating equations (GEE) model after adjusting for differences at baseline.ResultsA total of 50 patients in the NLCM group and 46 in the control group were recruited for data analysis. Results from the GEE model indicated that integrating NLCM into conventional care benefited patients in decreasing levels of pain and fatigue, as well as CRP value. These improvements were still observed for 2 years after NLCM.ConclusionNLCM was shown to be helpful in lowering pain, fatigue, and CRP, which implies that NLCM may be a reference in the provision of tailored care for those affected by rheumatism