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1.
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2.
To optimize the hydrolysis conditions to prepare hydrolysates of jellyfish umbrella collagen with the highest hydroxyl radical scavenging activity, collagen extracted from jellyfish umbrella was hydrolyzed with trypsin, and response surface methodology (RSM) was applied. The optimum conditions obtained from experiments were pH 7.75, temperature (T) 48.77 °C, and enzyme-to-substrate ratio ([E]/[S]) 3.50%. The analysis of variance in RSM showed that pH and [E]/[S] were important factors that significantly affected the process (P<0.05 and P<0.01, respectively). The hydrolysates of jellyfish umbrella collagen were fractionated by high performance liquid chromatography (HPLC), and three fractions (HF-1>3000 Da, 1000 Da<HF-2<3000 Da, and HF-3<1000 Da) were collected. The HF-2 fraction had the highest hydroxyl radical scavenging activity with the highest yield compared with the other two fractions. Furthermore, HF-2 also showed the strongest Cu2+-chelating ability and the best tyrosinase-inhibitory activity. Project (No. 2008BAD94B07) supported by the Hi-Tech Research and Development Program (863) of China  相似文献   

3.
ABSTRACT

This study was to investigate the role of students’ game self-efficacy in their game performance as well as in their visual behavior distributions and transfer patterns during their gameplay. A total of 48 university students were recruited for participating in a gameplaying task while wearing with an ASL Mobile Eye eye-tracker. After the gameplay, each participant was asked to report their self-efficacy of the gameplay. Based on the self-reported game self-efficacy (GSE) score, the participants were divided into the higher and lower GSE groups. Independent t tests were used to compare their game performances and eye-tracking indices for each area of interest. A lag sequential analysis was used to profile the visual transfer pattern for each group. The results showed that the higher GSE group had better performances than the lower GSE group. During the gameplay, the higher GSE students tended to pay more attention to the critical information for a successful play. In addition, the lag sequential analyses revealed different visual transfer patterns for the two GSE groups. The higher GSE group tended to show a critical-factor-centralized visual-trasfer pattern which demonstrated more planning and monitoring gameplaying strategies; while the lower GSE students, probably lacking the self-confidence of gameplaying, tended to pay more attention to the remaining time for the game.This study may provide suggestions for future game-based leraning system designs.  相似文献   

4.
This study investigates heterogeneity in adolescents' trajectories of global self‐esteem (GSE) and the relations between these trajectories and facets of the interpersonal, organizational, and instructional components of students' school life. Methodologically, this study illustrates the use of growth mixture analyses, and how to obtain proper student‐level effects when there are multiple schools, but not enough to support multilevel analyses. This study is based on a 4‐year, six‐measurement‐point, follow‐up of 1,008 adolescents (Mage = 12.6 years, SD = 0.6 at Time 1.) The results show four latent classes presenting elevated, moderate, increasing, and low trajectories defined based on GSE levels and fluctuations. The results show that GSE becomes trait‐like as it increases and that school life effects, moderated by gender, played an important role in predicting membership in these trajectories.  相似文献   

5.

Due to the low specificity and sensitivity of biomarkers in sepsis diagnostics, the prognosis of sepsis patient outcomes still relies on the assessment of clinical symptoms. Inflammatory response is crucial to sepsis onset and progression; however, the significance of inflammatory response-related genes (IRRGs) in sepsis prognosis is uncertain. This study developed an IRRG-based signature for sepsis prognosis and immunological function. The Gene Expression Omnibus (GEO) database was retrieved for two sepsis microarray datasets, GSE64457 and GSE69528, followed by gene set enrichment analysis (GSEA) comparing sepsis and healthy samples. A predictive signature for IRRGs was created using least absolute shrinkage and selection operator (LASSO). To confirm the efficacy and reliability of the new prognostic signature, Cox regression, Kaplan-Meier (K-M) survival, and receiver operating characteristic (ROC) curve analyses were performed. Subsequently, we employed the GSE95233 dataset to independently validate the prognostic signature. A single-sample GSEA (ssGSEA) was conducted to quantify the immune cell enrichment score and immune-related pathway activity. We found that more gene sets were enriched in the inflammatory response in sepsis patient samples than in healthy patient samples, as determined by GSEA. The signature of nine IRRGs permitted the patients to be classified into two risk categories. Patients in the low-risk group showed significantly better 28-d survival than those in the high-risk group. ROC curve analysis corroborated the predictive capacity of the signature, with the area under the curve (AUC) for 28-d survival reaching 0.866. Meanwhile, the ssGSEA showed that the two risk groups had different immune states. The validation set and external dataset showed that the signature was clinically predictive. In conclusion, a signature consisting of nine IRRGs can be utilized to predict prognosis and influence the immunological status of sepsis patients. Thus, intervention based on these IRRGs may become a therapeutic option in the future.

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6.
ABSTRACT

Purpose: Little is known about effective ways to operationalize agricultural innovation processes. We use the MasAgro program in Mexico (which aims to increase maize and wheat productivity, profitability and sustainability), and the experiences of middle level ‘hub managers’, to understand how innovation processes occur in heterogeneous and changing contexts. Design/methodology/approach: We use a comparative case study analysis involving research tools such as documentary review, key informant interviews, focus group discussions, and reflection workshops with key actors. Findings: Our research shows how a program, that initially had a relatively narrow technology focus, evolved towards an innovation system approach. The adaptive management of such a process was in response to context-specific challenges and opportunities. In the heterogeneous context of Mexico this results in diverse ways of operationalization at the hub level, leading to different collaborating partners and technology portfolios. Practical implications: MasAgro experiences merit analysis in the light of national public efforts to transform agricultural advisory services and accommodate pluralistic agricultural extension approaches in Latin America. Such efforts need long-term coherent macro level visions, frameworks and support, while the serendipitous nature of the process requires meso-level implementers to respond and adapt to and move the innovation process forward. Originality/value: This paper contributes to the debate on how to operationalize large programs by showing that the innovation support arrangements enacted in the field should allow for diversity and have a degree of flexibility to accommodate heterogeneous demands from farmers in different contexts as well as continuous changes in the politico- institutional environment.  相似文献   

7.
In response to continuing concerns about student attainment and participation in science and mathematics, the epiSTEMe project took a novel approach to pedagogy in these two disciplines. Using principles identified as effective in the research literature (and combining these in a fashion not previously attempted), the project developed topic modules for early secondary-school teaching in the UK, arranged for their implementation in classrooms, and evaluated the results. This paper reports the development, implementation, and evaluation of one of the epiSTEMe science modules. Entitled Forces and Proportional Relations, the module covers standard curricular material in the domain of forces, while paying particular attention to the proportional nature of many key constructs. It was developed in collaboration with a small group of teachers; implemented subsequently in 16 classrooms, in all cases involving students from the first year of secondary school; and evaluated through comparison with first-year students in 13 control classrooms who were studying the topic using established methods. Evaluation addressed topic mastery and opinions about the topic and the manner in which it was taught. While further research is required before definite conclusions are warranted, results relating to topic mastery provide grounds for optimism about the epiSTEMe approach. Furthermore, student opinions about the module were positive.  相似文献   

8.
The social, economic, political and ecological imperatives of sustainable development outlined in ’Our Common Future, Agenda 21’ and ’Caring for the Earth’ have established a renewed agenda for environmental education which links it very closely with development education. Teacher educators in Australia have responded to the need to link environmental and development education and to raise the level of attention usually devoted to them in teacher education programmes. The ’Environmental and Development Education Project for Teacher Education’ has been the result. The project has involved 20 educators, drawn from 11 universities, government departments and NGOs across Australia, in writing and trialing a set of 18 3‐hour workshop modules on environmental and development education for use in pre‐service teacher education courses. These modules, published in the project manual, ’Teaching for a Sustainable World’, illustrate how environmental education and development education are related and provide practical assistance for teacher educators who wish to include these important fields in their programmes. An intensive dissemination programme in 1993‐94 involves workshops for all Faculties of Education in Australia.  相似文献   

9.
ABSTRACT

This study aimed at improving the decision-making (DM) skills of 11th graders by incorporating a DM framework, visualisation tools, collaboration, and metacognitive guidance into a socioscientific issue context. Two classes, the experimental group (embedded metacognitive guidance, N?=?42) and the comparison group (no metacognitive guidance, N?=?32), were involved in the implementation of the experimental methodology. An open-ended test and worksheets were developed to assess the students’ DM skills. The results indicated that the two versions of the DM learning modules had similar effects on the improvement in the students’ DM skills, but there were significant differences in their overall skills in DM (Z?=??6.410, p?<?.001), generating criteria (Z?=??6.956, p?<?.001), and evaluating DM results (Z?=??2.533, p?<?.011) based on the student responses on the worksheets. These findings indicate that further studies need to explore the mechanism of metacognitive guidance for students with different socioscientific issue DM skills in e-learning environments.  相似文献   

10.
William M. Kinney 《PRIMUS》2017,27(8-9):880-888
Abstract

Educational modules can play an important part in revitalizing the teaching and learning of complex analysis. At the Westmont College workshop on the subject in June 2014, time was spent generating ideas and creating structures for module proposals. Sharing some of those ideas and giving a few example modules is the main purpose of this paper. The author has started to construct Mathematica-based educational modules for complex analysis, one of which is available in the online repository of supplemental materials for this article. The author has also begun work on a website called The Complex Moduli Project to make modules in complex analysis available worldwide, and invites others to join him in this endeavor.  相似文献   

11.
Changes in medical school curricula often require educators to develop teaching strategies that decrease contact hours while maintaining effective pedagogical methods. When faced with this challenge, faculty at the University of Cincinnati College of Medicine converted the majority of in‐person histology laboratory sessions to self‐study modules that utilize multiple audiovisual modalities and a virtual microscope platform. Outcomes related to this shift were investigated through performance on in‐house examinations, results of the United States Medical Licensing Examination® (USMLE®) Step 1 Examination, and student feedback. Medical School College Admissions Test® (MCAT®) scores were used as a covariate when comparing in‐house examinations. Results revealed no significant change in performance on in‐house examinations when the content being assessed was controlled (F(2, 506) = 0.676, P = 0.51). A significant improvement in overall practical examination grade averages was associated with the self‐study modules (F(6, 1164) = 10.213, P < 0.01), but gradual changes in examination content may explain this finding. The histology and cell biology portion of USMLE Step 1 Examination remained consistent throughout the time period that was investigated. Student feedback regarding the self‐study modules was positive and suggested that features such as instructor narrated videos were an important component of the self‐study modules because they helped recreate the experience of in‐person laboratory sessions. Positive outcomes from the student perspective and no drop in examination performance suggests that utilizing self‐study modules for histology laboratory content may be an option for educators faced with the challenge of reducing contact hours without eliminating content. Anat Sci Educ 10: 276–285. © 2016 American Association of Anatomists.  相似文献   

12.
Interactive computerized modules have been linked to improved retention of material in clinical medicine. This study examined the effects of a new series of interactive learning modules for preclinical medical education, specifically in the areas of quiz performance, perceived difficulty of concepts, study time, and perceived stress level. We randomly allocated 102 medical student volunteers into control and experimental groups. All participants studied selected anatomical and physiologic concepts using existing material (lecture notes, textbooks, etc.), while those in the experimental groups used the new interactive modules as well. All participants completed a quiz to test their knowledge of the assigned concepts and a survey to assess their subjective experiences in studying with the modules. We found a trend toward higher quiz scores in the experimental group relative to the control group, though it did not reach statistical significance (P = 0.31). Perceived concept difficulty was significantly reduced among those who studied with the modules (P < 0.001), and the number of hours spent studying the concepts was significantly increased (P = 0.028). Of those who used the modules, 83% rated them as “very helpful” or “extremely helpful.” No significant differences existed between participants' reported stress levels during the course of the study (P = 0.44). Our data suggest that medical students may learn more effectively and feel less intimidated by difficult concepts when interactive modules supplement traditional instruction. Anat Sci Ed 1:247–251, 2008. © 2008 American Association of Anatomists.  相似文献   

13.
On generalized extending modules   总被引：1，自引：0，他引：1  
A module M is called generalized extending if for any submodule N of M, there is a direct summand K of M such that N≤K and K/N is singular. Any extending module and any singular module are generalized extending. Any homomorphic image of a generalized extending module is generalized extending. Any direct sum of a singular (uniform) module and a semi-simple module is generalized extending. A ring R is a right Co-H-ring if and only if all right R modules are generalized extending modules.  相似文献   

14.
Two-component genes are kinds of genetic elements involved in regulation of antibiotic production inStreptomyces coelicolor. DNA microarray analysis revealed thatecrA1/A2, which mapped at distant sites fromred lucus and encode respectively the kinase and regulator, expressed coordinately with genes of Red specific biosynthetic pathway.ecrA1 andecrA2 gene-disruptive mutants were constructed using homogenotisation by reciprocal double crossover. Fermentation data showed that the undecylprodigiosin (Red) level of production was lower than that of wild-type strain. However, the change of the actinorhodin (Act) production level was not significant compared with wild type. Thus, these experiment results confirmed that the two-component systemecrA1/A2 was positive regulatory element forred gene cluster. Project (No.20172046) supported by the National Natural Foundation of China  相似文献   

15.
Relatively few studies of family literacy programmes have investigated parents' experiences and whilst a number of such programmes have been specifically aimed at fathers, little is known about the involvement of fathers in programmes which target both mothers and fathers. This article reports fathers' involvement in a family literacy programme and their home literacy practices with their young children. The article provides a definition of family literacy and describes the context of the study, which was carried out in socio‐economically disadvantaged communities in a northern English city. Fathers' participation in their children's literacy was investigated through interviews at the beginning and end of the programme (n = 85) and home visit records made by teachers throughout the programme. Quantitative and qualitative analysis of these data indicate that, while fathers' participation in the family literacy programme was not easily visible, almost all fathers were involved to some extent in home literacy events with their children. During the programme, teachers shared information about literacy activities and the importance of children having opportunities to share literacy activities with their parents. Data indicate that fathers who were not mentioned by mothers as having been involved in their children's literacy were significantly more likely to be on a low income than those who were reported as being engaged with their children in home literacy activities. Fathers in the study were involved in providing literacy opportunities, showing recognition of their children's achievements, interacting with their children around literacy and being a model of a literacy user. Although involved in all four of these key roles, fathers tended to be less involved in providing literacy opportunities than mothers. While fathers and sons engaged in what might be described as traditionally ‘masculine’ literacy activities, fathers were more often reported to be involved with their children in less obviously gendered home literacy activities. The article concludes with discussion of implications for involving fathers in future family literacy programmes.  相似文献   

16.
This paper reports research that engaged in the evaluation of an intervention programme designed to enhance the employability of a group of unemployed graduates. The evaluation adopted a quasi-experimental intervention research method employing a general self-efficacy scale, which had been validated in prior research. Results revealed that participants displayed higher levels of GSE after engagement in the programme. Results also revealed the effect of ‘behavioural plasticity’ on the intervention experiences of unemployed graduate participants. The findings of this study are discussed in relation to programme design, recruitment and evaluation.  相似文献   

17.

Background

Tumor-derived exosomes were considered to be potential candidates for tumor vaccines because they are abundant in immune-regulating proteins, whereas tumor exosomal miRNAs may induce immune tolerance, thereby having an opposite immune function.

Objective

This study was designed to separate exosomal protein and depleted exosomal microRNAs (miRNAs), increasing the immune activity of exosomes for activating dendritic cell/cytokine-induced killer cells (DC/CIKs) against pancreatic cancer (PC).

Methods

PC-derived exosomes (PEs) were extracted from cultured PANC-1 cell supernatants and then ruptured; this was followed by ultrafiltered exosome lysates (UELs). DCs were stimulated with lipopolysaccharide (LPS), PE, and UEL, followed by co-culture with CIKs. The anti-tumor effects of DC/CIKs against PC were evaluated by proliferation and killing rates, tumor necrosis factor-α (TNF-α) and perforin secretion. Exosomal miRNAs were depleted after lysis and ultrafiltration, while 128 proteins were retained, including several immune-activating proteins.

Results

UEL-stimulated DC/CIKs showed a higher killing rate than LPS- and PE-stimulated DC/CIKs.

Conclusions

miRNA-depleted exosome proteins may be promising agonists for specifically activating DC/CIKs against PC.
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18.
This paper reports the development of the Negative Group Work Experiences questionnaire (NGWE), an assessment tool for measuring negative experiences of group work. Study 1 involved two samples of undergraduate psychology students (second‐year sample n = 425; first‐year sample n = 443), who completed research modules incorporating substantial elements of assessed group work. Participants completed a 39‐item inventory designed to measure their negative experiences of group work as part of their general module evaluation. Exploratory and confirmatory factor analysis of the second‐year sample indicated four interpretable and reliable factors: lack of group commitment, group fractionation, task disorganisation, and storming. Confirmatory factor analysis of the first‐year data set confirmed and cross‐validated the factor structure of the second‐year sample. Study 2 (n > 254) confirmed the criterion validity of the NGWE. The NGWE is proposed as a useful tool for evaluating group processes, especially in large group teaching which involves collaborative group work.  相似文献   

19.
Visual instruction complementing verbal lectures is known to promote learning among students. In this study, the role of visual instruction in engaging learners effectively via the simplification of technical concepts was examined. Different aspects of visualisation, such as order of presenting and dimensionality, were tested to observe their effect on students’ approach to learning and learning outcomes. In this mixed‐method quasi‐non‐experimental explanatory study, visual instruction was applied in one of the undergraduate architecture modules that teaches fundamentals of building systems, which students often find difficult to comprehend. Three key variables, including spatial cognitive ability, approach to learning and learning outcomes, were measured using statistically valid instruments along with students’ feedback and interviews. These factors were also measured for the control group that did not receive visual instruction (n = 32), to assess the effect of the intervention. When taught with visualisation, students (n = 69), showed a significant increase in deep approach to learning (e.g., deep motive: t = 2.584, p = 0.011). In interviews, students expressed a deeper interest in the subject and reported that the topic was engaging in class. Visualisation favours students with a higher spatial ability and, thus, is useful for design students who receive spatial ability training in the course. Two‐dimensional visuals must be followed and preceded by three‐dimensional visuals to provide advanced organisation and the connection of new knowledge with known organisational models to be made.  相似文献   

20.
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