1,154 research outputs found

    Continuous-time histories: observables, probabilities, phase space structure and the classical limit

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    In this paper we elaborate on the structure of the continuous-time histories description of quantum theory, which stems from the consistent histories scheme. In particular, we examine the construction of history Hilbert space, the identification of history observables and the form of the decoherence functional (the object that contains the probability information). It is shown how the latter is equivalent to the closed-time-path (CTP) generating functional. We also study the phase space structure of the theory first through the construction of general representations of the history group (the analogue of the Weyl group) and the implementation of a histories Wigner-Weyl transform. The latter enables us to write quantum theory solely in terms of phase space quantities. These results enable the implementation of an algorithm for identifying the classical (stochastic) limit of a general quantum system.Comment: 46 pages, latex; in this new version typographical errors have been removed and the presentation has been made cleare

    The Speech Style of Students in Classroom Interaction of Arabic Classes on Pondok Modern Darussalam Gontor 1 Ponorogo

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    Keywords: speech style, conversation, student, teacher.While most people are born with thephysical ability to talk, not all can communicate well unless they make specialefforts to develop and refine this skill further. This study was aimed to answer three problems of study. They are (1) what arethe speech styles used by the student while having conversation with his friend and his teacher in Arabic class on Pondok Modern Darussalam Gontor 1 Ponorogo (2)what the style occurs dominantly used by the student while having conversation with his friend and his teacher, and (3) what are the possible factors causing the uses of speech style when they communicate with the teacher and their friends. In this study, the researcher used the theory from Ryding (2005) about speech styles and Holmes (1992) about factors which influence the speech style.In this study, the researcher used descriptive qualitative approach because the researcher more focused on the explanation and description. The data of this studywere 30 conversations between student and student, and student and the teacher ofhigh, middle and low level class in Arabic class. In analyzing the data, the researcherdid the process of style identification and explanation about the style and the possiblefactors of using certain style.The result shows that while having conversation with the teacher, all students in high level class used formal style, in middle class almost all of the student used formal style, and in low class level, half of the student used formal style. While having conversation with his friend, almost all student in high, middle and low level class used the combination of formal and informal style. In addition, there were threepossible factors influencing the uses of speech style. Those factors were theparticipant (social status), setting and topic, but there were also some conversations which were not influenced by those three factors which could be caused by the lack of competence.From this study, the researcher suggest the next researcher analyze the speechstyle using another theory such as from Chaika, Holmes, Keraf and etc. The researcher also suggests future researchers analyze the function of speech style indaily conversatio

    Exploring the Connection between Immigration and Violent Crime Rates in US Cities, 1980-2000

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    A popular perception is that immigration causes higher crime rates. Yet, historical and contemporary research finds that at the individual level, immigrants are not more inclined to commit crime than the native born. Knowledge of the macro-level relationship between immigration and crime, however, is characterized by important gaps. Most notably, despite the fact that immigration is a macro-level social process that unfolds over time, longitudinal macro-level research on the immigration-crime nexus is virtually nonexistent. Moreover, while several theoretical perspectives posit sound reasons why over-time changes in immigration could result in higher or lower crime rates, we currently know little about the veracity of these arguments. To address these issues, this study investigates the longitudinal relationship between immigration and violent crime across U. S. cities and provides the first empirical assessment of theoretical perspectives that offer explanations of that relationship. Findings support the argument that immigration lowers violent crime rates by bolstering intact (two-parent) family structures

    Membrane-dependent activities of human 15-lox-2 and its murine counterpart implications for murine models of atherosclerosis

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    © 2016 by The American Society for Biochemistry and Molecular Biology, Inc. The enzyme encoded by the ALOX15B gene has been linked to the development of atherosclerotic plaques in humans and in a mouse model of hypercholesterolemia. In vitro, these enzymes, which share 78% sequence identity, generate distinct products from their substrate arachidonic acid: the human enzyme, a 15-S-hydroperoxy product; and the murine enzyme, an 8-S-product. We probed the activities of these enzymes with nanodiscs as membrane mimics to determine whether they can access substrate esterified in a bilayer and characterized their activities at the membrane interface. We observed that both enzymes transform phospholipid-esterified arachidonic acid to a 15-S-product. Moreover, when expressed in transfected HEK cells, both enzymes result in significant increases in the amounts of 15-hydroxyderivatives of eicosanoids detected. In addition, we show that 15-LOX-2 is distributed at the plasma membrane when the HEK293 cells are stimulated by the addition Ca 2+ ionophore and that cellular localization is dependent upon the presence of a putative membrane insertion loop. We also report that sequence differences between the human and mouse enzymes in this loop appear to confer distinct mechanisms of enzyme-membrane interaction for the homologues

    Efficacy and Selectivity of Pre- and Post-emergence Herbicides in Chia (Salvia hispanica L.) under Mediterranean Semi-arid Conditions

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    In the present study, the selectivity and efficacy of several post and pre-emergence herbicides in chia (Salvia hispanica L.) were examined. Field experiments were conducted at two locations with different soil types and environmental conditions. Our results showed that the pre-emergence application of pendimethalin, oxyfluorfen and linuron reduced total weed density by 71-74%, 74-82% and 53-55%, respectively. Despite their high effectiveness, the above-mentioned herbicides had a negative effect on plant density and biomass yield. In addition, herbicides bentazon and fluazifop-p-butyl which applied post-emergence did not affect significantly plant height and biomass yield. In conclusion, the herbicides linuron, pendimethalin and oyxfluorfen do not seem to be a viable option for weed control in chia crop, whereas the post-emergence applied herbicides did not affect significantly plants’ growth. Further evaluation of chia tolerance to herbicides is needed under different application rates in order to make safe suggestions for chemical control of weeds

    Effectiveness of clinical dashboards as audit and feedback or clinical decision support tools on medication use and test ordering: a systematic review of randomized controlled trials

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    BACKGROUND Clinical dashboards used as audit and feedback (A&F) or clinical decision support systems (CDSS) are increasingly adopted in healthcare. However, their effectiveness in changing the behavior of clinicians or patients is still unclear. This systematic review aims to investigate the effectiveness of clinical dashboards used as CDSS or A&F tools (as a standalone intervention or part of a multifaceted intervention) in primary care or hospital settings on medication prescription/adherence and test ordering. METHODS Seven major databases were searched for relevant studies, from inception to August 2021. Two authors independently extracted data, assessed the risk of bias using the Cochrane RoB II scale, and evaluated the certainty of evidence using GRADE. Data on trial characteristics and intervention effect sizes were extracted. A narrative synthesis was performed to summarize the findings of the included trials. RESULTS Eleven randomized trials were included. Eight trials evaluated clinical dashboards as standalone interventions and provided conflicting evidence on changes in antibiotic prescribing and no effects on statin prescribing compared to usual care. Dashboards increased medication adherence in patients with inflammatory arthritis but not in kidney transplant recipients. Three trials investigated dashboards as part of multicomponent interventions revealing decreased use of opioids for low back pain, increased proportion of patients receiving cardiovascular risk screening, and reduced antibiotic prescribing for upper respiratory tract infections. CONCLUSION There is limited evidence that dashboards integrated into electronic medical record systems and used as feedback or decision support tools may be associated with improvements in medication use and test ordering

    A Novel Chemically Differentiated Mouse Embryonic Stem Cell-Based Model to Study Liver Stages of Plasmodium berghei.

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    Asymptomatic and obligatory liver stage (LS) infection of Plasmodium parasites presents an attractive target for antimalarial vaccine and drug development. Lack of robust cellular models to study LS infection has hindered the discovery and validation of host genes essential for intrahepatic parasite development. Here, we present a chemically differentiated mouse embryonic stem cell (ESC)-based LS model, which supports complete development of Plasmodium berghei exoerythrocytic forms (EEFs) and can be used to define new host-parasite interactions. Using our model, we established that host Pnpla2, coding for adipose triglyceride lipase, is dispensable for P. berghei EEF development. In addition, we also evaluated in-vitro-differentiated human hepatocyte-like cells (iHLCs) to study LS of P. berghei and found it to be a sub-optimal infection model. Overall, our results present a new mouse ESC-based P. berghei LS infection model that can be utilized to study the impact of host genetic variation on parasite development

    A Novel Chemically Differentiated Mouse Embryonic Stem Cell-Based Model to Study Liver Stages of Plasmodium berghei.

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    Asymptomatic and obligatory liver stage (LS) infection of Plasmodium parasites presents an attractive target for antimalarial vaccine and drug development. Lack of robust cellular models to study LS infection has hindered the discovery and validation of host genes essential for intrahepatic parasite development. Here, we present a chemically differentiated mouse embryonic stem cell (ESC)-based LS model, which supports complete development of Plasmodium berghei exoerythrocytic forms (EEFs) and can be used to define new host-parasite interactions. Using our model, we established that host Pnpla2, coding for adipose triglyceride lipase, is dispensable for P. berghei EEF development. In addition, we also evaluated in-vitro-differentiated human hepatocyte-like cells (iHLCs) to study LS of P. berghei and found it to be a sub-optimal infection model. Overall, our results present a new mouse ESC-based P. berghei LS infection model that can be utilized to study the impact of host genetic variation on parasite development

    Non-Markovian Dynamics and Entanglement of Two-level Atoms in a Common Field

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    We derive the stochastic equations and consider the non-Markovian dynamics of a system of multiple two-level atoms in a common quantum field. We make only the dipole approximation for the atoms and assume weak atom-field interactions. From these assumptions we use a combination of non-secular open- and closed-system perturbation theory, and we abstain from any additional approximation schemes. These more accurate solutions are necessary to explore several regimes: in particular, near-resonance dynamics and low-temperature behavior. In detuned atomic systems, small variations in the system energy levels engender timescales which, in general, cannot be safely ignored, as would be the case in the rotating-wave approximation (RWA). More problematic are the second-order solutions, which, as has been recently pointed out, cannot be accurately calculated using any second-order perturbative master equation, whether RWA, Born-Markov, Redfield, etc.. This latter problem, which applies to all perturbative open-system master equations, has a profound effect upon calculation of entanglement at low temperatures. We find that even at zero temperature all initial states will undergo finite-time disentanglement (sometimes termed "sudden death"), in contrast to previous work. We also use our solution, without invoking RWA, to characterize the necessary conditions for Dickie subradiance at finite temperature. We find that the subradiant states fall into two categories at finite temperature: one that is temperature independent and one that acquires temperature dependence. With the RWA there is no temperature dependence in any case.Comment: 17 pages, 13 figures, v2 updated references, v3 clarified results and corrected renormalization, v4 further clarified results and new Fig. 8-1

    Ultrasound and microbubbles for the treatment of ocular diseases : From preclinical research towards clinical application

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    The unique anatomy of the eye and the presence of various biological barriers make efficacious ocular drug delivery challenging, particularly in the treatment of posterior eye diseases. This review focuses on the combination of ultrasound and microbubbles (USMB) as a minimally invasive method to improve the efficacy and targeting of ocular drug delivery. An extensive overview is given of the in vitro and in vivo studies investigating the mechanical effects of ultrasound-driven microbubbles aiming to: (i) temporarily disrupt the blood–retina barrier in order to enhance the delivery of systemically administered drugs into the eye, (ii) induce intracellular uptake of anticancer drugs and macromolecules and (iii) achieve targeted delivery of genes, for the treatment of ocular malignancies and degenerative diseases. Finally, the safety and tolerability aspects of USMB, essential for the translation of USMB to the clinic, are discussed.Peer reviewe
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