123 research outputs found

    Conservation Laws in Higher-Order Nonlinear Optical Effects

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    Conservation laws of the nonlinear Schr\"{o}dinger equation are studied in the presence of higher-order nonlinear optical effects including the third-order dispersion and the self-steepening. In a context of group theory, we derive a general expression for infinitely many conserved currents and charges of the coupled higher-order nonlinear Schr\"{o}dinger equation. The first few currents and charges are also presented explicitly. Due to the higher-order effects, conservation laws of the nonlinear Schr\"{o}dinger equation are violated in general. The differences between the types of the conserved currents for the Hirota and the Sasa-Satsuma equations imply that the higher-order terms determine the inherent types of conserved quantities for each integrable cases of the higher-order nonlinear Schr\"{o}dinger equation

    The Ubiquitous Inflaton in String-Inspired Models

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    A string theory based inflationary model is developed where the inflaton interacts with a multitude of massive string level states causing dissipation of vacuum energy. Inflation terminates in a warm Universe without the need for reheating.Comment: In Press Physical Review Letters 1999, modified titl

    Spectroscopy of 18^{18}Na: Bridging the two-proton radioactivity of 19^{19}Mg

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    The unbound nucleus 18^{18}Na, the intermediate nucleus in the two-proton radioactivity of 19^{19}Mg, was studied by the measurement of the resonant elastic scattering reaction 17^{17}Ne(p,17^{17}Ne)p performed at 4 A.MeV. Spectroscopic properties of the low-lying states were obtained in a R-matrix analysis of the excitation function. Using these new results, we show that the lifetime of the 19^{19}Mg radioactivity can be understood assuming a sequential emission of two protons via low energy tails of 18^{18}Na resonances

    Cooperation, Norms, and Revolutions: A Unified Game-Theoretical Approach

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    Cooperation is of utmost importance to society as a whole, but is often challenged by individual self-interests. While game theory has studied this problem extensively, there is little work on interactions within and across groups with different preferences or beliefs. Yet, people from different social or cultural backgrounds often meet and interact. This can yield conflict, since behavior that is considered cooperative by one population might be perceived as non-cooperative from the viewpoint of another. To understand the dynamics and outcome of the competitive interactions within and between groups, we study game-dynamical replicator equations for multiple populations with incompatible interests and different power (be this due to different population sizes, material resources, social capital, or other factors). These equations allow us to address various important questions: For example, can cooperation in the prisoner's dilemma be promoted, when two interacting groups have different preferences? Under what conditions can costly punishment, or other mechanisms, foster the evolution of norms? When does cooperation fail, leading to antagonistic behavior, conflict, or even revolutions? And what incentives are needed to reach peaceful agreements between groups with conflicting interests? Our detailed quantitative analysis reveals a large variety of interesting results, which are relevant for society, law and economics, and have implications for the evolution of language and culture as well

    New findings on carambola fruit fly hosts in South America.

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    Bactrocera carambolae Drew & Hancock (Diptera: Tephritidae), a mosca-da-carambola, é uma praga quarentenária presente no Brasil, restrita aos estados do Amapá, Pará e Roraima. Sua dispersão para outras regiões do país poderia causar sérios prejuízos socioeconômicos. Os frutos foram coletados em árvores urbanas, quintais residenciais e pequenos pomares nas áreas rurais e urbanas do município de Oiapoque, Amapá, Brasil. Um total de 240 amostras (11.126 frutos; 288,8 kg) de 33 espécies vegetais (16 nativas e 17 introduzidas) de 19 famílias foram coletadas. Bactrocera carambolae foi isolada dos frutos de 13 espécies vegetais. Além de B. carambolae, foram coletados neste estudo espécimes de 8 espécies de Anastrepha. Além disso, 5 espécies de parasitoides (Hymenoptera; 3 espécies de Braconidae e 2 de Figitidae) associadas a Anastrepha spp. foram identificadas. No geral, este estudo acrescenta 3 novos registros à lista de plantas hospedeiras de B. carambolae no Brasil (Artocarpus heterophyllus Lam.; Moraceae, Passiflora quadrangularis L.; Passifloraceae e Ziziphus mauritiana Lam.; Rhamnaceae), dois deles novos registros na América do Sul (A. heterophyllus e P. quadrangularis) e demonstra novas interações entre espécies de Anastrepha e plantas hospedeiras no extremo norte do estado do Amapá. Notavelmente, este é o primeiro relato da espécie de figitídeo Aganaspis nordlanderi Wharton no estado do Amapá

    Pharmacist intervention program to enhance hypertension control: a randomised controlled trial

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    Objective Studies have demonstrated that hypertension remains inadequately managed throughout the world, with lack of adherence to BP-lowering medication being a major factor. The aim of the present study was to evaluate if a pharmaceutical care program could improve antihypertensive medication adherence and blood pressure control. Setting This study was conducted in a secondary care hypertension/dyslipidemia outpatient clinic in the university teaching hospital of Cova da Beira Hospital Centre, Covilhã, located in the Eastern Central Region of Portugal. Method This report evaluates the pharmacist’s interventions during a prospective randomised controlled trial, from July 2009 to June 2010. Patients with diagnosis of essential hypertension attending the clinic for routine follow-up were randomly allocated either to a control group (no pharmaceutical care) or to an intervention group (quarterly follow-up by a hospital pharmacist during a 9-month period). The pharmacist interventions, aimed to increase medication adherence and blood pressure control, involved educational interventions and counselling tips directed to the patient. Main outcome measure Systolic blood pressure, diastolic blood pressure and blood pressure control (according to JNC 7 guidelines) assessed at the baseline visit and at the end of pharmaceutical care were the main outcome measures. Blood pressure measurements were performed by blinded nurses. Medication adherence was also evaluated, using a validated questionnaire at baseline and at the end of investigation. Results A total of 197 hypertensive patients were randomly assigned to the study (99 in the control group and 98 in the intervention group). Although there were no significant differences (P > 0.05) in both groups concerning mean age, gender, body mass index, and antihypertensive pharmacotherapy, blood pressure control was higher in the intervention group (P = 0.005) at the end of the study. Significant lower systolic blood pressure (−6.8 mmHg, P = 0.006) and diastolic blood pressure (−2.9 mmHg, P = 0.020) levels were observed in the intervention group. Medication adherence was also significantly higher in the intervention group at the end of the study (74.5% vs. 57.6%, P = 0.012).Conclusion Pharmacist intervention can significantly improve medication adherence and blood pressure control in patients treated with antihypertensive agents

    Persistence and efficacy of a new formulation based on dog allomonal repellents against Rhipicephalus sanguineus sensu lato tick

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    Beagles are less susceptible to Rhipicephalus sanguineus sensu lato tick due to the production of the allomones benzaldehyde and 2-hexanone. Our previous published work showed that these compounds can reduce tick burden on susceptible dogs. Here we tested the hypothesis that an increase in repellent dose and release rate could increase repellent efficacy and persistence. Slow-release formulations of these compounds, with higher doses and release rates, were tested on artificially-infested dogs. Ten dogs were randomly assigned to two groups with five dogs each. The treated group received collars with slow-release formulations of the compounds attached, while the control group received collars with clean formulations attached. Five environmental infestations were performed, with the number of ticks (at all stages) on the dogs being counted once a day for 40 days. No significant increase in repellent efficacy was observed with the higher doses and release rates, whereas a greater persistence in repellent activity was observed. Treatment with the formulations resulted in a two-to-three-fold reduction in the number of immature stage ticks for up to three weeks. However, the number of adults was similar in both groups. Loss of repellent activity after the third week of testing coincided with a marked change in the relative release rates for the two compounds. It is hypothesized that relative amounts, rather than absolute amounts, of repellent release from slow-release formulations are important for repellent activity. We also hypothesize that the avoidance of less-preferred hosts by ticks relies on olfactory-mediated perception of specific blends of volatile cues from less preferred hosts

    Physician Perception of Blood Pressure Control and Treatment Behavior in High-Risk Hypertensive Patients: A Cross-Sectional Study

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    Objective: We examined physician perception of blood pressure control and treatment behavior in patients with previous cardiovascular disease and uncontrolled hypertension as defined by European Guidelines. Methods: A cross-sectional study was conducted in which 321 primary care physicians throughout Spain consecutively studied 1,614 patients aged ≥18 years who had been diagnosed and treated for hypertension (blood pressure ≥140/90 mmHg), and had suffered a documented cardiovascular event. The mean value of three blood pressure measurements taken using standardized procedures was used for statistical analysis. Results: Mean blood pressure was 143.4/84.9 mmHg, and only 11.6% of these cardiovascular patients were controlled according to 2007 European Guidelines for Hypertension Management target of <130/80 mmHg. In 702 (49.2%) of the 1426 uncontrolled patients, antihypertensive medication was not changed, and in 480 (68.4%) of these cases this was due to the physicianś judgment that blood pressure was adequately controlled. In 320 (66.7%) of the latter patients, blood pressure was 130-139/80-89 mmHg. Blood pressure level was the main factor associated (inversely) with no change in treatment due to physician perception of adequate control, irrespective of sociodemographic and clinical factors. Conclusions: Physicians do not change antihypertensive treatment in many uncontrolled cardiovascular patients because they considered it unnecessary, especially when the BP values are only slightly above the guideline target. It is possible that the guidelines may be correct, but there is also the possibility that the care by the physicians is appropriate since BP <130/80 mmHg is hard to achieve, and recent reviews suggest there is insufficient evidence to support such a low BP targetFunding for this study was obtained from RECORDATI ESPAÑA, S.L through an unrestricted grant. Krista Lundelin has a ‘‘Rio Hortega’’ research training contract (Expediente CM10/00327) from the Ministry of Science and Innovation (Instituto de Salud Carlos III), Spain Governmen

    Cross-Sector Partnerships to Address Social Issues: Challenges to Theory and Practice

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