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231.
Purpose: The present study aimed to determine if autonomic cardiac modulation was influenced by acute exposure to normobaric hypoxia. Method: Ten healthy male lowland dwellers completed five block-randomised single-blinded, crossed-over acute exposures to a normobaric hypoxic environment, each separated by 24 hours’ recovery (20.3%, 17.4%, 14.5%, 12.0% and 9.8% FIO2). Supine recordings were made of arterial oxygen saturation and electrocardiogram (ECG). RR intervals from the ECG trace were analysed for time (SDNN, lnrMSSD), frequency (lnVLF, lnLF, lnHF, lnTP, LFnu, and HFnu), and nonlinear (DFA-α1 and SampEn) heart rate variability components. Results: A significant reduction in arterial SaO2 occurred with reduced FIO2, along with a rise in heart rate (Cohen’s d?=?1.16, 95% Confidence Interval [2.64–6.46]), significant at 9.8% FIO2. A decrease in autonomic cardiac modulation was also found as shown by a statistically significant (at 9.8% FIO2) decrease in lnTP (d?=?1.84 [1.74–1.94]), and SampEn (d?=?0.98 [0.83–1.12]) and an increase in DFA-α1 (d?=?0.72 [0.60–0.84]) from normoxia at 9.8% FIO2. Conclusion: The decrease in variability indicated a reduction in autonomic cardiac modulation. There appears to be a threshold ~9.8% FIO2 (~6000?m equiv.), below which significant alterations in autonomic control occur.  相似文献   
232.
Instructional Science - Engaging in engineering tasks can help students learn science concepts. However, many engineering tasks lead students to focus more on the success of their construction than...  相似文献   
233.
The present paper focuses on the application of a structured template, maximum impact flow (MIF), in order to encourage young students in the area of optics and optical engineering. MIF introduces a template in terms of individual steps and linked functionality and is shown to fuse separate learning tools together into a cohesive unit. Prioritization and teaching structures are also discussed with the promotion of technology identified as a key factor.  相似文献   
234.

Objective

The authors explored the feasibility and possible benefit of tablet-based educational materials for patients in clinic waiting areas.

Methods

We distributed eight tablets preloaded with diagnosis-relevant information in two clinic waiting areas. Patients were surveyed about satisfaction, usability, and effects on learning. Technical issues were resolved.

Results

Thirty-seven of forty patients completed the survey. On average, the patients were satisfied in all categories.

Conclusions

Placing tablet-based educational materials in clinic waiting areas is relatively easy to implement. Patients using tablets reported satisfaction across three domains: usability, education, and satisfaction.  相似文献   
235.
Borck  C. Ray 《The Urban Review》2020,52(2):376-391

Despite persistent class and race inequalities in educational attainment and achievement in the U.S., hegemonic cultural ideologies and urban education politics and policies continue to proceed from an insistence that education is the great equalizer. These ideologies do not take into account the ways that normative school culture and pedagogical praxes take for granted middle-class, white-supremacist cultural assumptions that privilege student populations whose social locations already probabilize high rates of achievement and attainment. Vast research published in The Urban Review and elsewhere has demonstrated the importance and efficacy of culturally sustaining pedagogy for improving outcomes for economically marginalized students of color (Allen in Urban Rev 47(1):209–231, 2015; Delpit in Harv Educ Rev 56(4):379–386, 1995; Farinde-Wu et al. in Urban Rev 49(2):279–299, 2017; Gay in culturally responsive teaching: theory, research, and practice, Teachers College Press, New York, 2010; Graves in Berkeley Rev Educ 5(1):5–32, 2014; Jemal in Urban Rev 49(4):602–626, 2017; Ladson-Billings in Crossing over to Canaan: the journey of new teachers in classrooms, Jossey-Bass, San Francisco, 2001, The dreamkeepers: successful teachers of African American children, Jossey-Bass Publishers, San Francisco, 2009; Lee in Culture, literacy and learning: taking bloom in the midst of the whirlwind, Teachers College Press, New York, 2006; Marciano in Urban Rev 49(1):169–187, 2016; Nieto in Language, culture, and teaching: critical perspectives, Routledge, New York, 2010; Paris in Educ Res 41(3):93–97, 2012; Paris and Alim in Culturally sustaining pedagogies: teaching and learning for justice in a changing world, Teachers College Press, New York, 2017; Wiggan and Watson in Urban Rev 48(5):766–798, 2016; Yosso in Race Ethn Edu, 8(1):69–91, 2005). This article uses rich ethnographic data from a transfer school in Brooklyn, New York that serves financially insecure youth of color who are “over-age and under-credited.” These data and my analysis showcase the expertise and indigenous knowledges of teachers who practice cultural relevance and critical racial awareness in order to engage, retain, graduate and prepare students who are historically and presently marked for failure by an education system that has always been more adept at reproducing social inequality than disrupting it (Borck in Qual Inq 20(10):1–8, 2016).

  相似文献   
236.
Purpose: This paper reports the results of survey research conducted with tribal producers between 2011 and 2012 on 19 of the largest American Indian reservations in Idaho, Nevada, North Dakota, Oregon, South Dakota, and Washington. The purpose of the research was to identify potential barriers to sustainable agriculture on reservation lands. This article reports the results of this research in an effort to promote Extension professionals' understanding of these barriers, which may help to improve outreach programs on American Indian reservations. Understanding the obstacles to sustaining agriculture that American Indian tribes face may inform international agricultural outreach efforts to increase food security targeting indigenous and tribal peoples worldwide.

Design/Methodology/Approach: American Indian agricultural producers comprised the study group. Study objectives included: (1) identify agricultural and natural resource issues of greatest concern to a self-selected sample of tribal agricultural producers on reservation lands; (2) evaluate access to Extension and other US Department of Agriculture outreach and assistance programs; and (3) evaluate the quality of these programs in terms of their relativity to tribal needs.

Findings: Study results indicate that tribal agricultural producers surveyed ranked 29 of 39 agricultural and natural resource issues as a concern. Similarly, they rated access to and quality of outreach programs as fair. Further, tribal producers operating on reservation trust land rated issues more severely than did tribal producers operating on fee simple lands.

Practical Implications: Results of this research will help Extension and other outreach professionals to understand the barriers indigenous and tribal peoples face in sustaining agricultural operations, particularly tribal groups living on federally reserved trust lands, such as American Indians. An increased understanding can inform agricultural policy-makers and outreach professionals in improving programs designed to increase agricultural sustainability, improve food security, enhance economic well-being and improve quality of life of indigenous and tribal peoples worldwide.

Originality/Value: This research provides important information to agricultural policy-makers and Extension professionals striving to sustain agricultural productivity and enhance food security with indigenous and tribal peoples.  相似文献   

237.
OBJECTIVE: To assess: (1) ethnic differences in the health-risk behaviors, mental health problems, and adverse parenting beliefs during pregnancy of low-income Mexican American and European American women; and, (2) the extent to which these risks varied with levels of acculturation among low-income Mexican American women. METHOD: Participants were 594 primiparous, low-income, urban women. A cross-sectional design was used to compare the 331 Mexican American women to the 263 European American. Language was used to assess the level of acculturation of the Mexican American women. Interviews were used to evaluate health-risk behaviors, mental health problems, and adverse parenting beliefs. RESULTS: In comparison to European American women, Mexican American women were at lower risk for cigarette smoking during pregnancy and higher risk for adverse parenting beliefs. Among Mexican American women, Spanish speakers were at lower risk for cigarette smoking and mental health problems during pregnancy, and higher risk for adverse parenting beliefs than bilingual and English speakers. CONCLUSIONS: The findings indicate that ethnic differences in cigarette smoking and parenting beliefs during pregnancy were concentrated on the less acculturated, low-income, and primarily unmarried Spanish speaking Mexican American women. Moreover, acculturation is differentially related to cigarette smoking and parenting beliefs. Therefore, acculturation needs to be considered in the development of preventive interventions in order to appropriately target the specific needs of different sub-populations of Mexican Americans.  相似文献   
238.
ABSTRACT

Blended learning has been a feature of higher education practice and research for almost two decades. This article takes stock of current blended learning research, contributing to the growing number of meta-analyses of higher education and blended learning research more generally, through a review of ninety-seven articles relating to blended learning in higher education published in fifteen journals between 2012 and mid-2017. The review focused on where and when the articles were published; their provenance, scale, scope; methodological approach; the broad research themes; and definition of blended learning used. The review shows that despite its ubiquity, blended learning’s definition is all-encompassing; its spread is global but research is dominated by key players; it is of technical interest; and its research is small-scale, individually focused, seeking to evidence the benefits of blended learning. The article concludes with recommendations of how higher education research could provide institutions with evidence to ensure their ‘best of blends’.  相似文献   
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240.
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