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Se reseñó el libro: The evolution of the go-between in Spanish literature through the sixteenth century.

The aim of this study is to determine to what extent the emotional factors such as attitude, fear of negative evaluation and stress level for academic expectations predict students' mathematics achievements. In this quantitative study a prediction research design, type of correlational design, was used to anticipate results by using particular variables as predictors. The study was conducted on 352 middle school students attending a middle school in Bursa. Students' mathematics scores, Mathematics Attitude Scale (MAS), Fear of Negative Evaluation Scale Short Form (FNES) and Academic Expectations Stress Inventory (AESI) were used for data collection. In order to determine participants' level of attitude toward mathematics, fear of negative evaluation and stress level for academic expectations descriptive statistics were used. Secondly to compare participants' score on three measurements according to their gender, class level, and mathematics scores, multivariate analysis of variance (MANOVA) was employed. According to results gender did not make a significant difference on mathematics attitude, fear of negative evaluation and stress level separately, as well. Class level increases, students' positive attitudes towards mathematics decreases. Students with high mathematics scores had significantly more positive feelings towards mathematics than students with low mathematics scores. The results of correlation analysis indicated that mathematics success was significantly and positively associated to mathematics attitude while it was significantly and negatively associated to fear of negative evaluation and stress for academic expectations. [ABSTRACT FROM AUTHOR]

Despatching ground forces – the Field Force – to the continent constituted a cardinal element of British grand strategy from early 1934 to early 1938. In winter 1933-1934, through the Defence Requirements Sub-Committee [DRC], senior Foreign Office and Treasury officials, working with the Chiefs of Staff, advised the Cabinet to begin moderate rearmament – ultimately £52 million – with a deadline of 1939. Central to DRC recommendations was the Field Force to underwrite British maintaining the European balance of power through military support for France and the Low Countries to deter possible German aggression. When reporting in February 1934, the DRC identified two adversary Powers requiring improved British defences: Germany, the 'ultimate potential enemy', and Japan, of lesser importance. The War Office immediately began creating the Force, built around four divisions. In 1935, given the Abyssinian crisis, Italy joined the list of potential adversaries, and the Cabinet approved almost £400 million DRC-recommended additional defence spending, again, by 1939. The government guided by the Foreign Office monitored the balance; and War Office planning now centred on a 16-division Field Force. However, in May 1937, Neville Chamberlain rose to the premiership and initiated a defence review requiring more spending – £1.625 billion in two tranches: 1939 and 1941 – but eliminating the Field Force. Eschewing the balance, Britain would rely on powerful air and naval forces to maintain national and imperial security. However, after Germany's conquest of Czechoslovakia in March 1939 and a darkened continental milieu, the Field Force was reborn to underpin British strategy. [ABSTRACT FROM AUTHOR]

We consider the process of establishing thermal equilibrium behind an ideal shock front in molecular crystals and its possible role in initiating chemical reaction at high shock pressures. A new theory of equilibration via multiphonon energy transfer is developed to treat the scattering of shock-induced phonons into internal molecular vibrations. Simple analytic forms are derived for the change in this energy transfer at different Hugoniot end states following shock compression. The total time required for thermal equilibration is found to be an order of magnitude or faster than proposed in previous work; in materials representative of explosive molecular crystals, equilibration is predicted to occur within a few picoseconds following the passage of an ideal shock wave. Recent molecular dynamics calculations are consistent with these time scales. The possibility of defect-induced temperature localization due purely to nonequilibrium phonon processes is studied by means of a simple model of the strain field around an inhomogeneity. The specific case of immobile straight dislocations is studied, and a region of enhanced energy transfer on the order of 5 nm is found. Due to the rapid establishment of thermal equilibrium, these regions are unrelated to the shock sensitivity of a material but may allow temperature localization at high shock pressures. Results also suggest that if any decomposition due to molecular collisions is occurring within the shock front itself, these collisions are not enhanced by any nonequilibrium thermal state. [ABSTRACT FROM AUTHOR]

Detailed simulations are reported for the dynamics of electrons and nuclei during the cis to trans photoisomerization of stilbene. Our method, which employs a semiclassical description of both the nuclear motion and the radiation field, is described in the text. After excitation of electrons from the highest occupied molecular orbital (HOMO) to the lowest unoccupied molecular orbital (LUMO) by a femtosecond-scale laser pulse, two principal avoided crossings are observed between the HOMO and LUMO levels, each of which leads to substantial depopulation of the LUMO. Based on our results and those of other groups, we propose that the first such HOMO–LUMO coupling can lead to the formation of 4a,4b-dihydrophenanthrene (DHP). The second coupling, on the other hand, leads to the formation of trans-stilbene. It is found that pyramidalization of the two carbon atoms of the vinyl group is involved significantly in both couplings, and that rotation of the two phenyl rings, together with their interaction, plays an important role in the first coupling. The occurrence along the same trajectory of two couplings, one leading to DHP and the other leading to isomerization, is a significant observation, and one which indicates that further theoretical and experimental investigations would be of considerable interest. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We propose a very simple and efficient way to stabilize ions issued from a collision complex through a femtosecond coherently controlled pump/probe process. Starting from a van der Waals complex, one can initiate a collision at a well-defined time and with a restricted impact parameter. Formation of stable ionic complex can be achieved by ionizing the collision complex at the "right time." We present in this paper its application to the NaI-(CH[SUB3]CN)[SUB1-2] system. Na[SUP+]-CH[SUB3]CN ion formation is coherently controlled by ionization of colliding Na atom on CH[SUB3]CN molecules issued from the dissociation of NaI within NaI-(CH[SUB3]CN)[SUB1-2]. Classical mechanic calculations using simple ionization/dissociation conditions can reproduce the experimental data and give an insight into the control of such a reaction. [ABSTRACT FROM AUTHOR]

In this paper, we discuss a number of key methodological and data issues presented to researchers in determining base funding requirements for Australian schools. In particular, we outline the commonly used 'reference school'‐ based approach to determining a benchmark level of school effectiveness and efficiency, and discuss some of its limitations. In contrast to this method, we present a new approach to estimating base funding requirements that, aided by the use of more granular data, provides a more robust approach to understanding and measuring school effectiveness and efficiency. [ABSTRACT FROM AUTHOR]

Using structural equation modeling, this study found that prior reading skill was significantly associated with children's reported physical activity levels, which was in turn significantly associated with English language arts (ELA) and math achievement, among 526 3rd-grade students. The New York City Metropolitan area students completed the Physical Activity Questionnaire for Older Children (PAQ-C), which measured average activity levels. Controlling for race, ethnicity, Body Mass Index, learning disability status, and socioeconomic status at the child and school levels, developmental reading assessment (DRA) scores had a strong, independent association with physical activity levels, which in turn had a moderate association with current ELA and a strong association with math achievement. Hispanic ethnicity had a significant negative association with activity levels (relative to Whites), though the positive association of physical activity with ELA and math achievement was stronger among Hispanics than it was among the samples of Black and White students. These findings suggest that enhanced academic achievement significantly influences, and is significantly influenced by, student physical activity levels. Schools should consider ways to increase student physical activity, including using low/no cost in-class exercises. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations of clusters containing hundreds of naphthalene molecules were used to investigate vibrational cooling and vibrational heating. The effects of isotopic substitution, modeled by changing the masses of the extended-atom C–H groups, were also studied. In vibrational cooling, a hotter molecule (300 K) is allowed to interact with a cold cluster (10 K). Pure clusters of normal, light, and heavy naphthalene molecules were cooled with roughly the same time constant (∼50 ps). However, in mixed clusters containing a normal molecule in an isotopically substituted heavy or light cluster, the normal molecule cooled much more slowly, indicating the dominant cooling mechanism in pure clusters is resonant intermolecular vibrational energy transfer. In vibrational heating studies, a cold molecule (10 K) is allowed to interact with a cluster which is much hotter (300 K) than in the vibrational cooling studies (10 K). Normal molecules in pure or mixed clusters were heated at about the same rates and those rates were about what was seen in vibrational cooling simulations. At the higher temperatures of the vibrational heating simulation, phonon-assisted intermolecular vibrational energy transfer between unlike molecules in mixed clusters occurs at rates similar to resonant transfer processes between like molecules in pure clusters. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Femtosecond laser studies have been performed on the photoisomerization reactions of cis-stilbene to obtain the most detailed understanding to date of a polyatomic isomerization reaction in a condensed phase environment. These experiments demonstrate that vibrationally hot product molecules are formed within a few hundred femtoseconds of the escape of the molecule from the cis* region of the potential energy surface. Although the cis to trans reaction may proceed via a twisted intermediate structure, this intermediate is not intercepted on the ∼150 fs time scale. The frictional effects on the cis to trans reaction coordinate are found to be important and account for the anisotropy of the trans product molecules. Specific experiments presented in detail are the absorption spectrum of electronically excited cis molecules (cis*); the anisotropy decays for cis* showing motion along the reaction coordinate; the detection of the trans-stilbene product using transient fluorescence and transient absorption, confirming that the reaction generates hot product states and that the Franck–Condon modes are largely spectators in the reaction; the anisotropy (alignment) of trans product molecules illustrating the effect of friction coupling overall motion to the reaction coordinate; and a theoretical treatment of three-pulse anisotropy experiments. [ABSTRACT FROM AUTHOR]

Trans-stilbene photoproduces appearing from the photoisomerization of cis-stilbene within 150 fs are observed to be vibrationally hot, but with a nonthermal population distribution. The product electronic spectrum depends on the incident photon energy. Clearly, intramolecular vibrational energy redistribution is not ultrafast. [ABSTRACT FROM AUTHOR]

Aims and objectives To synthesise research examining college student sexual violence disclosure and campus sexual violence resources and services. Background Recently, the issue of sexual violence within the college population has garnered attention worldwide. The prevalence of sexual violence within college students is alarmingly high. Survivors often experience negative outcomes (e.g. health-related consequences, impact on education). Efforts have been made to address this significant public health concern. Design Systematic review of published literature. Methods Studies were identified through systematic searches of PubMed, CINAHL and PsycInfo of articles published between January 2010-February 2015. A total of 672 articles were identified. After screening, 16 articles were included in this review. Results A lack of consistency in how sexual violence was referred to and measured was identified. Research on college student sexual violence disclosure has primarily been conducted in six areas: (1) informal disclosure, (2) formal disclosure, (3) friends' perceptions of disclosure, (4) process/effects of disclosure on the survivor, (5) barriers to disclosure and (6) social support in the disclosure process. Research related to campus sexual violence resources and services has primarily focused on: (1) students' knowledge, (2) students' utilization and (3) students' suggestions. Synthesised findings are presented. Conclusions Sexual violence impacts college student survivors and the campus community as a whole. To appropriately assist/address sexual violence, a thorough understanding of college student sexual violence disclosure and campus sexual violence resources/services is necessary. Suggestions for researchers, colleges and nurses are provided. Relevance to clinical practice Nurses who serve students, especially those at on-campus student health centres, are opportunely placed to address sexual violence. Findings highlight the need for nurses to use consistent definitions of sexual violence when identifying survivors. Nurses should take measures to increase disclosure and promote sexual violence resources/services provided by their facility. Additional suggestions for nurses are provided. [ABSTRACT FROM AUTHOR]

Although violent offending and victimization share many features, they can affect adolescent social relationships in distinct ways. To understand these differences, we take a network approach to examine the mechanisms responsible for similarities (i.e., homophily) in violent offending and violent victimization among friends. Our goal is to determine whether the social network mechanisms that produce homophily for violent offending are similar to or different from those that produce homophily for violent victimization. By using stochastic actor-oriented modeling and two waves of friendship network data for 1,948 respondents from the National Longitudinal Study of Adolescent to Adult Health, we examine homophily mechanisms of preference for similarity, avoidance, and influence with respect to youth violence and victimization. The results demonstrate that homophily observed for violent offending primarily reflects selection of similar others, whereas homophily observed for victimization reflects the tendency among alters to avoid victimized youth. These findings have important implications for future research and suggest that, among adolescents, violent offending and victimization homophily are the result of unique social processes. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was twofold: (1) to estimate the prevalence of comorbid posttraumatic stress disorder (PTSD), major depressive episode (MDE), and substance use disorder (SUD); and (2) to identify risk factors for patterns of comorbidity among adolescents affected by disasters. Method: A population-based sample of 2,000 adolescents (51% female; 71% Caucasian, 26% African American) aged 12 to 17 years (M = 14.5, SD = 1.7) and their parents was recruited from communities affected by the spring 2011 tornadoes in Alabama and Joplin, Missouri. Participants completed structured telephone interviews assessing demographic characteristics, impact of disaster, prior trauma history, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), symptoms of posttraumatic stress disorder (PTSD) and major depressive episode (MDE), and substance use disorder (SUD) symptoms. Prevalence estimates were calculated for PTSD + MDE, PTSD + SUD, MDE + SUD, and PTSD + MDE + SUD. Hierarchical logistic regression was used to identify risk factors for each comorbidity profile. Results: Overall prevalence since the tornado was 3.7% for PTSD + MDE, 1.1% for PTSD + SUD, 1.0% for MDE + SUD, and 0.7% for PTSD + MDE + SUD. Girls were significantly more likely than boys to meet criteria for PTSD + MDE and MDE + SUD (ps <.05). Female gender, exposure to prior traumatic events, and persistent loss of services were significant risk factors for patterns of comorbidity. Parental injury was associated with elevated risk for PTSD + MDE. Adolescents should be evaluated for comorbid problems, including SUD, following disasters so that appropriate referrals to evidence-based treatments can be made. Conclusions: Results suggest that screening procedures to identify adolescents at risk for comorbid disorders should assess demographic characteristics (gender), impact of the disaster on the family, and adolescents' prior history of stressful events. [ABSTRACT FROM AUTHOR]

Propagation of an ultrashort laser pulse in the atmosphere is considered with allowance for diffraction and dispersion properties of the atmosphere. Results of numerical simulation of the propagation of pulses with a duration from several to tens of femtoseconds in air at a room temperature are presented. A rapid spreading of such pulses under the corrected Gaussian form of the time envelope is shown. The propagation of a pulse with a negative initial chirp in dry and humid air is calculated; the chirp makes it possible to partially compensate dispersion and diffraction effects. The distance at which the pulse duration becomes minimal is derived as a function of air humidity. [ABSTRACT FROM AUTHOR]

Background Relatively few studies have examined prevalence and predictors of posttraumatic stress disorder ( PTSD) or major depressive episode ( MDE) in disaster-affected adolescents. Fewer still have administered diagnostic measures or studied samples exposed to tornadoes, a common type of disaster. Further, methodologic problems limit the generalizability of previous findings. This study addressed prevalence estimates and risk factors for PTSD and MDE among adolescents exposed to the Spring 2011 tornado outbreak in Alabama and Joplin, Missouri. Methods A large ( N = 2000), population-based sample of adolescents and caregivers, recruited randomly from tornado-affected communities, participated in structured telephone interviews. PTSD and MDE prevalence were estimated for the overall sample, by gender, and by age. Hierarchical logistic regression was used to identify risk factors for PTSD and MDE. Results Overall, 6.7% of adolescents met diagnostic criteria for PTSD and 7.5% of adolescents met diagnostic criteria for MDE since the tornado. Girls were significantly more likely than boys to meet diagnostic criteria for MDE, and older adolescents were more likely than younger adolescents to report MDE since the tornado. Female gender, prior trauma exposure, and an injured family member were associated with greater risk for PTSD and MDE. Specific incident characteristics (loss of services, concern about others' safety) were associated with greater PTSD risk; prior disaster exposure was associated with lower MDE risk. Conclusions However, most adolescents were resilient following tornado exposure, roughly 1 in 15 developed PTSD, 1 in 13 developed MDE, and many more endorsed subclinical mental health problems. Information regarding specific risk factors can guide early screening, prevention, and intervention efforts in disaster-affected communities. [ABSTRACT FROM AUTHOR]