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21.
The purpose of this longitudinal study is to examine the relationship between teen sexting and offline sexual behavior. Using a sample of 1134 Czech adolescents aged 10–18 (Mage = 13.84, SD = 1.94, girls = 58.8%) from 55 schools, the latent growth model of offline sexual behavior with sexting as a time-varying covariate was employed. Participants differed at baseline for offline sexual behavior at both individual and school levels, and they varied in the growth rate of offline sexual behavior at the individual level. Only age and sensation seeking explained the variability at baseline of offline sexual behavior. The positive association between sexting and offline sexual behavior was not constant across time. However, sexting at baseline predicted offline sexual behavior a half year and one year later. Sexting may be treated as a precursor of offline sexual behavior.  相似文献   
22.
This article offers an overview of what every theologian and scholar of religion should know about changes in biblical studies that have taken place concerning the past depreciation of Second Temple Judaism, the use of newly discovered sources and their implications, as well as integrative approaches to top-down (reflected beliefs, prescribed practices, textual sources) and bottom-up (intuitive beliefs, lived practices, material culture) processes. Changes in the field lead to the re-writing of the history of the Bible and of Judaean society in the Greco-Roman context. By means of this co-authored research article, we wish to demonstrate the benefit of, as well as the need for, interdisciplinary work in the study of antiquity.  相似文献   
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Abstract

The dependence of the normal-state resistivity, resistive superconducting transition (T c, ΔT c), and of the upper critical-field slope (dH c2/dT|T=Tc) on density has been investigated for several YBa2Cu3O9-x(x?2.1) samples. The resistivity decreases rapidly with increasing density, whereas T c and ΔT c are rather insensitive to a change in density. dH c2/dT|Tc depends sensitively on the preparation conditions. The implications of these results both for the evaluation of the parameters relevant to the understanding of the nature of superconductivity and for the technological applications of granular superconductors are briefly discussed.  相似文献   
25.
This study examined how U.S., Finnish, and Irish educators identified and supported struggling readers. Using Johnston's (2011) framework for evaluating reading interventions and activity theory (Engeström, 1999), we interviewed educators in four U.S., three Irish, and three Finnish schools. In the United States, the adoption of three beliefs—reductionist reading philosophy, difficulties as cognitive and remediated through instruction, and reading problems as unexpected phenomena—reinforced a skills-driven approach. Irish and Finnish educators adopted a more holistic view of reading, and teachers used formative assessment to support struggling students over extended periods while working collaboratively with other staff. Discussion focuses on how these beliefs influenced divisions of labor, roles and responsibilities, and the urgency with which difficulties were addressed.  相似文献   
26.
Provability logic is a modal logic for studying properties of provability predicates, and Interpretability logic for studying interpretability between logical theories. Their natural models are GL-models and Veltman models, for which the accessibility relation is well-founded. That’s why the usual counterexample showing the necessity of finite image property in Hennessy-Milner theorem (see [1]) doesn’t exist for them. However, we show that the analogous condition must still hold, by constructing two GL-models with worlds in them that are modally equivalent but not bisimilar, and showing how these GL-models can be converted to Veltman models with the same properties. In the process we develop some useful constructions: games on Veltman models, chains, and general method of transformation from GL-models/frames to Veltman ones.  相似文献   
27.
Rotation of a visual image in mind is associated with a slow posterior negative deflection of the event-related potential (ERP), termed rotation-related negativity (RRN). Retention of a visual image in short-term memory is also associated with a slow posterior negative ERP, termed negative slow wave (NSW). We tested whether short-term memory retention, indexed by the NSW, contributes to the RRN. ERPs were recorded in the same subjects in two tasks, a mental rotation task, eliciting the RRN, and a visual short-term memory task, eliciting the NSW. Over both right and left parietal scalp, no association was found between the NSW and the RRN amplitudes. Furthermore, adjusting for the effect of the NSW had no influence on a significant association between the RRN amplitude and response time, an index of mental rotation performance. Our data indicate that the RRN reflects manipulation of a visual image but not its retention in short-term memory.  相似文献   
28.
Abstract

The exact solution of the q-state Potts bridge model with competing ferromagnetic and antiferromagnetic interactions is obtained and corresponding regular and critical behaviour studied.  相似文献   
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Objective

Transcranial Doppler sonography (TCD) enables monitoring of blood flow velocities (BFVs) in basal cerebral arteries during different cognitive tasks performance with great temporal resolution. So far, BFVs changes during mental activity were monitored primarily in middle cerebral arteries (MCAs) and little is known about these changes in anterior cerebral arteries (ACAs).

Aim

To determine the effect of different cognitive tasks performance on BFV changes and hemispheric dominance in ACAs and to assess the most suitable activation test for monitoring of BFV changes in ACAs.

Methods

Fourteen right-handed, healthy subjects aged 20–26 were included in the study. BFVs in both ACAs were recorded simultaneously during performance of cognitive tasks designed to activate frontal lobes: phonemic verbal fluency test (pVFT), Stroop tests and Trail Making Tests (TMTs).

Results

A statistically significant BFV increase was recorded in both ACAs during performance of all cognitive tasks. Statistically significant right ACA dominance was found during performance of pVFT and TMTB. The most significant BFV increase was obtained during performance of TMTB.

Conclusion

Our result addressed cognitive tests with great activation potential for monitoring of ACAs that might be used in distinguishing of healthy individuals and patients with neurovascular or neurodegenerative diseases.  相似文献   
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