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21.
Afforestation in China provides carbon sequestration and prevents soil erosion, but its remote impacts on climate in other regions via the coupling of forest energy fluxes with atmospheric circulation are largely unknown. Here, we prescribe inventory-based forest cover change and satellite-observed leaf area index from 1982 to 2011 in a coupled land-atmosphere model to simulate their biophysical climate effects. Both local and global surface air temperatures show a seasonal contrast in response to past vegetation cover expansion over China: a phenomenon we primarily attribute to a variation of seasonality of vegetation greening. A large cooling in spring results in concurrent decreases in geopotential height over China and zonal wind over Mongolia, causing a dipole structure in the upper troposphere over the Arctic. This accounts for ∼58% of simulated spring warming over the Russian Arctic and ∼61% of simulated spring cooling over the Canadian Artic. Our results imply that spring vegetation dynamics in China may affect climate in northern high latitudes.  相似文献   
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The Luria-Nebraska Neuropsychological Battery-Children's Revision (LNNB-Children's Revision) and The Minnesota Percepto-Diagnostic Test (MPD) were administered to 40 learning disabled (LD) students. Correlations were run between the scales of the LNNB-Children's Revision and MPD scores across the sample. Coefficients ranged from .07 to .71 for the intercorrelations of the scales of the LNNB-Children's Revision. Low correlations (−.10 to −.27) were found between MPD T scores and the LNNB-Children's Revision Scales, but raw scores from the MPD had somewhat higher correlations with the LNNB (.18 to .65).  相似文献   
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A common practice for counteracting response acquiescence in psychological measures has been to employ both negatively and positively worded items. However, previous research has highlighted that the reliability of measures can be affected by this practice (Spector, 1992). The purpose of the present study was to examine the effect that the presence of negatively worded items has on the internal reliability of the Group Environment Questionnaire (GEQ). Two samples (N = 276) were utilized, and participants were asked to complete the GEQ (original and revised) on separate occasions. Results demonstrated that the revised questionnaire (containing all positively worded items) had significantly higher Cronbach alpha values for three of the four dimensions of the GEQ. Implications, alternatives, and future directions are discussed.  相似文献   
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This study compared heart rate recovery (HRR) after incremental maximal exercise performed at the same external power output (Pext) on dry land ergocycle (DE) vs. immersible ergocycle (IE). Fifteen young healthy participants (30?±?7 years, 13 men and 2 women) performed incremental maximal exercise tests on DE and on IE. The initial Pext on DE was 25?W and was increased by 25?W/min at a pedalling cadence between 60 and 80?rpm, while during IE immersion at chest level in thermoneutral water (30°C), the initial Pext deployment was at a cadence of 40?rpm which was increased by 10?rpm until 70?rpm and thereafter by 5?rpm until exhaustion. Gas exchange and heart rate (HR) were measured continuously during exercise and recovery for 5?min. Maximal HR (DE: 176?±?15 vs. IE 169?±?12?bpm) reached by the subjects in the two conditions did not differ (P?>?.05). Parasympathetic reactivation parameters (ΔHR from 10 to 300?s) were compared during the DE and IE HR recovery recordings. During the IE recovery, parasympathetic reactivation in the early phase was more predominant (HRR at Δ10–Δ60?s, P?<?.05), but similar in the late phase (HRR at Δ120–Δ300?s, P?>?.05) when compared to the DE condition. In conclusion, incremental maximal IE exercise at chest level immersion in thermoneutral water accelerates the early phase parasympathetic reactivation compared to DE in healthy young participants.  相似文献   
25.
Beery's Developmental Test of Visual-Motor Integration was individually administered to 193 school-age children. Test protocols were factor analyzed by a principal component solution. Four factors were obtained, indicating that the test does not measure a unitary dimension of perceptual-motor development, but rather four distinct levels or stages for the age range of children investigated. The structural features of the designs that make up the test were used to define the factors. It is argued that a more useful interpretation of performance on this test would be one that designates visualmotor processing in terms of levels, not age equivalents.  相似文献   
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Abstract

This paper describes a classroom‐based research study designed to determine how students in an undergraduate multicultural education course experience difficult and emotional content about racism. Samples of students’ reflective writing were used as sources of data, and Janet Helms’ theory of racial identity development served as the framework for analysis. Findings suggest that coursework in multicultural education can influence white students’ racial identities. In addition, the experiences of one white student are highlighted as she grappled with issues of white privilege and multicultural teaching. This study illustrates how reflective writing in combination with teaching practices informed by psychological theory helped to expand students’ understanding of racism while facilitating the development of their racial identities.  相似文献   
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The role and continued relevance of state telecommunications regulators have been challenged by the development of competition, the introduction of new technologies, and the increasing dominance of federal authority. An important role that state utility commissions can play in the current telecommunications environment is to provide consumer education and information about consumer protection, competition, and universal service. Commissions can use their Web sites as effective tools in educating and informing consumers. This study analyzes the consumer-related telecommunications information included on the Web sites of the commissions in the 50 states and the District of Columbia to determine whether, and how well, state commissions are using their Web sites to educate and inform.  相似文献   
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