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931.
Abstract

Rural America has historically been plagued with a disproportionate shortage of health, education, and other public services. However, the application of rapidly changing telecommunications technologies can alleviate many of the problems associated with these isolated and “technologically undernourished” areas. Technologies such as low‐power television, direct broadcast satellites, and satellite‐fed cable services offer the opportunity for building a rural telecommunications network and thus improving services and the quality of life. However, in order for this goal to be realized, the economic constraints presented by insufficient consumer demand and unprofitable markets must be overcome. Direct government subsidization or increased support of projects may be necessary to encourage the private sector to increase investment in telecommunications facilities in rural communities.  相似文献   
932.
Given increasing interest in evidence-based policy, there is growing attention to how well the results from rigorous program evaluations may inform policy decisions. However, little attention has been paid to documenting the characteristics of schools or districts that participate in rigorous educational evaluations, and how they compare to potential target populations for the interventions that were evaluated. Utilizing a list of the actual districts that participated in 11 large-scale rigorous educational evaluations, we compare those districts to several different target populations of districts that could potentially be affected by policy decisions regarding the interventions under study. We find that school districts that participated in the 11 rigorous educational evaluations differ from the interventions' target populations in several ways, including size, student performance on state assessments, and location (urban/rural). These findings raise questions about whether, as currently implemented, the results from rigorous impact studies in education are likely to generalize to the larger set of school districts—and thus schools and students—of potential interest to policymakers, and how we can improve our study designs to retain strong internal validity while also enhancing external validity.  相似文献   
933.
934.
Abstract

A study was conducted to determine the effectiveness of male and female extension agents in reaching farmers, especially women, with extension services in Nigeria. Specially the study determined the levels of awareness of and participation in extension activities, adoption of and technical knowledge of recommended agricultural technologies/practices, satisfaction with the quality of extension services provided and agents' credibility of men and women farmers under male and female extension agents supervision. Data gathered from 141 men and 72 women farmers supervised by male agents and 22 men and 93 women farmers supervised by female agents in Oyo, Kaduna and Rivers State Agricultural Development Projects in Nigeria form the empirical basis for the study. Even though men farmers are more aware of and participated more in the extension activities organised by agents than women farmers, the study shows that women farmers, who are supervised by female agents have more access to extension services than women farmers who work with male agents. Specifically, women farmers, who had females for extension agents had relatively higher levels of awareness and participation of the extension activities organised, adoption of and technical knowledge of recommended technologies/practices and satisfaction with the quality of agents' services and credibility. These differential effects of female and male agents on women's access to extension are significant for the delivery of extension services to women farmers, especially. Extension organisations must encourage and recruit more females for extension work done at the same time evolve strategies that will help male agents to work better with women farmers.  相似文献   
935.
In the current study, we quantified biological movement variability on the start and early acceleration phase of sprinting. Ten male athletes aged 17-23 years (100-m personal best: 10.87 +/- 0.36s) performed four 10-m sprints. Two 250-Hz cameras recorded the sagittal plane action to obtain the two-dimensional kinematics of the block start and initial strides from subsequent manually digitized APAS motion analysis. Infra-red timing lights (80Hz) were used to measure the 10-m sprinting times. The coefficient of variation (CV%) calculation was adjusted to separate biological movement variability (BCV%) from estimates of variability induced by technological error (SEM%) for each individual sprinter and measure. Pearson's product-moment correlation and linear regression analysis were used to establish relationships between measures of BCV% and 10-m sprint start performance (best 10-m time) or 10-m sprint start performance consistency (10-m time BCV%) using SPSS version 12.0. Measurement error markedly inflated traditional measures of movement variability (CV%) by up to 72%. Variability in task outcome measures was considerably lower than that observed in joint rotation velocities. Consistent generation of high horizontal velocity out of the blocks led to more stable and faster starting strides.  相似文献   
936.
937.
Contemporary models of adult speech perception acknowledge that the processing of linguistic and nonlinguistic aspects of the speech signal are interdependent. But when in development does this interdependence first emerge? In the adult literature, one way to demonstrate this relationship has been to examine how language experience affects talker identification. Thus, in this study, 4- to 5-month-old infants (N = 96) were tested on their ability to tell apart talkers in a familiar language (English) compared to unfamiliar languages (Polish or Spanish). Infants readily distinguished between talkers in the familiar language but not in the unfamiliar languages, supporting the hypothesis that the integrated processing of linguistic and nonlinguistic information in speech is early emerging and robust.  相似文献   
938.
The study used data from the second wave of the Children's Worlds Survey to explore the relation between children's experiences of bullying victimization (physical and psychological) and their subjective well-being (SWB) across three age groups (8, 10, and 12) and 15 global geographical regions. The sample consists of 47,029 children randomly selected from 15 countries. Data were analyzed using structural equation modeling and multigroup confirmatory factor analysis. The results show appropriate fit structure for the overall model, and that the combined influence of physical and psychological bullying made a significant contribution to SWB across age groups and geographical regions. The findings are interpreted using Cummins's (1995) Homeostasis Theory of SWB.  相似文献   
939.
940.
Viewers regularly watch television with others, but the role of coviewing is often overlooked in entertainment effects models. Further, the models are rarely investigated in natural settings, limiting their ecological validity. The current study used experience sampling via text message to examine college students’ daily coviewing behaviors. Momentary assessments were taken 3 times a day for 1 week. Respondents reported their happiness during viewing and the enjoyableness of their experiences. Consistent with emotional contagion theory, data suggest that increases in emotional intensity mediated the effect of emotional contagion on program enjoyment, but only among respondents who reported coviewing with someone else. These results provide preliminary evidence that social context is partially responsible for contagious transfer of affect during entertainment experiences.  相似文献   
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