253 research outputs found

    Observing Coherence Effects in an Overdamped Quantum System

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    It is usually considered that the spectrum of an optical cavity coupled to an atomic medium does not exhibit a normal-mode splitting unless the system satisfies the strong coupling condition, meaning the Rabi frequency of the coherent coupling exceeds the decay rates of atom and cavity excitations. Here we show that this need not be the case, but depends on the way in which the coupled system is probed. Measurements of the reflection of a probe laser from the input mirror of an overdamped cavity reveal an avoided crossing in the spectrum which is not observed when driving the atoms directly and measuring the Purcell-enhanced cavity emission. We understand these observations by noting a formal correspondence with electromagnetically-induced transparency of a three-level atom in free space, where our cavity acts as the absorbing medium and the coupled atoms play the role of the control field

    Metacognitive improvement and symptom change in a 3-month treatment for borderline personality disorder.

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    Recognizing and reflecting on one's own and other people's mental states represent a major difficulty for patients with borderline personality disorder (BPD). Only recently have studies begun exploring whether these capacities increase with successful therapies and if such an improvement is linked with outcome. The present study investigated whether metacognition would improve and if its improvement was related with symptom change in BPD patients. The transcripts from the first and the penultimate session of a ten-session version of good psychiatric management were analysed with the MAS-R scale in a N = 37 BPD sample. Patients, selected from a previously published RCT (Kramer et al., 2014), were assigned either to the good psychiatric management treatment or to the same treatment with the addition of the Motive-Oriented Therapeutic Relationship (Caspar, 2007), a form of therapeutic relationship based on an individualized case formulation. Symptoms were assessed with the OQ-45. Findings partially support the hypotheses. First, improvement in capacities to understand others' mind, to take a critical distance from one's own rigid and maladaptive beliefs, and to use behavioural and attentional strategies to face adversities is found in both treatment groups. Controlling for marital status, only the ability to differentiate between reality and representations remains significant. Second, no link between metacognitive change and symptom change during treatment is found. However, a link is observed between the increase in metacognition and symptom reduction at 6-month follow-up. Results invite to further investigate the role of metacognition in therapy change through different modalities and in longer-term treatments. The development of metacognitive processes and their links with symptom change were examined during a short-term treatment in 37 borderline patients Improvement was found in capacities to understand others' mind, to take a critical distance from own rigid and maladaptive beliefs, and to use behavioural and attentional strategies even in a short-term treatment Controlling for marital status, only the ability to take a critical distance from representations remained significant A link was observed between increase in metacognition and symptom reduction at 6-month follow-up Understanding and tailoring interventions to specific metacognitive difficulties could be associated with symptom change during treatment for BPD patients

    TB Hackathon: Development and Comparison of Five Models to Predict Subnational Tuberculosis Prevalence in Pakistan

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    Pakistan’s national tuberculosis control programme (NTP) is among the many programmes worldwide that value the importance of subnational tuberculosis (TB) burden estimates to support disease control efforts, but do not have reliable estimates. A hackathon was thus organised to solicit the development and comparison of several models for small area estimation of TB. The TB hackathon was launched in April 2019. Participating teams were requested to produce district-level estimates of bacteriologically positive TB prevalence among adults (over 15 years of age) for 2018. The NTP provided case-based data from their 2010–2011 TB prevalence survey, along with data relating to TB screening, testing and treatment for the period between 2010–2011 and 2018. Five teams submitted district-level TB prevalence estimates, methodological details and programming code. Although the geographical distribution of TB prevalence varied considerably across models, we identified several districts with consistently low notification-to-prevalence ratios. The hackathon highlighted the challenges of generating granular spatiotemporal TB prevalence forecasts based on a cross-sectional prevalence survey data and other data sources. Nevertheless, it provided a range of approaches to subnational disease modelling. The NTP’s use and plans for these outputs shows that, limitations notwithstanding, they can be valuable for programme planning

    Resonant optomechanics with a vibrating carbon nanotube and a radio-frequency cavity

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    In an optomechanical setup, the coupling between cavity and resonator can be increased by tuning them to the same frequency. We study this interaction between a carbon nanotube resonator and a radiofrequency tank circuit acting as a cavity. In this resonant regime, the vacuum optomechanical coupling is enhanced by the dc voltage coupling the cavity and the mechanical resonator. Using the cavity to detect the nanotube’s motion, we observe and simulate interference between mechanical and electrical oscillations. We measure the mechanical ring down and show that further improvements to the system could enable the measurement of mechanical motion at the quantum limit

    Hyperfine and spin-orbit coupling effects on decay of spin-valley states in a carbon nanotube

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    The decay of spin-valley states is studied in a suspended carbon nanotube double quantum dot via leakage current in Pauli blockade and via dephasing and decoherence of a qubit. From the magnetic field dependence of the leakage current, hyperfine and spin-orbit contributions to relaxation from blocked to unblocked states are identified and explained quantitatively by means of a simple model. The observed qubit dephasing rate is consistent with the hyperfine coupling strength extracted from this model and inconsistent with dephasing from charge noise. However, the qubit coherence time, although longer than previously achieved, is probably still limited by charge noise in the device

    Prognostic impact of meningeal dissemination in primary CNS lymphoma (PCNSL): experience from the G-PCNSL-SG1 trial

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    Background We evaluated the frequency and prognostic impact of meningeal dissemination (MD) in immunocompetent adult patients with primary central nervous system lymphoma treated in a randomized phase III trial. Patients and methods MD was evaluated at study entry and defined by lymphoma proof in the meningeal compartment detected by at least one of the following methods: cerebrospinal fluid (CSF) cytomorphology, detection of clonal B cells by IgH PCR in CSF or contrast enhancement of the leptomeninges on magnetic resonance imaging (MRI). Results Data on MD were available in 415 patients, of those, MD was detected in 65 (15.7%): in 44/361 (12.2%) by CSF cytomorphology, in 16/152 (10.5%) by PCR and in 17/415 (4.1%) by MRI. Major patients' characteristics and therapy did not significantly differ between patients with MD (MD+) versus those without MD (MD−). There was a significant correlation of MD with CSF pleocytosis (>5/μl; P45 mg/dl). Median progression-free survival was 6.7 months [95% confidence interval (CI) 0-14.5] in MD+ and 8.3 months (5.7-10.8) in MD− patients (P=0.95); median overall survival was 21.5 months (95% CI 16.8-26.1) and 24.9 months (17.5-32.3), respectively (P=0.98). Conclusion MD was detected infrequently and had no impact on outcome in this tria

    Defining the research agenda to measure and reduce tuberculosis stigmas

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    This is an Open Access article, © 2017 International Union Against Tuberculosis and Lung Disease. Content in the UH Research Archive is made available for personal research, educational, and non-commercial purposes only. Unless otherwise stated, all content is protected by copyright, and in the absence of an open license, permissions for further re-use should be sought from the publisher, the author, or other copyright holder.Crucial to finding and treating the 4 million tuberculosis (TB) patients currently missed by National TB Programs, TB stigma is receiving well-deserved and long-delayed attention at the global level. However, the ability to measure and evaluate the success of TB stigma reduction efforts is limited by the need for additional tools. At a 2016 TB stigma measurement meeting held in The Hague, stigma experts discussed and proposed a research agenda around four themes: (1) Drivers: What are the main drivers and domains of TB stigma(s)?; (2) Consequences: How consequential are TB stigmas? How are negative impacts most felt?; (3) Burden: What is the global prevalence and distribution of TB stigma(s)? What explains any variation? (4): Intervention: What can be done to reduce the extent and impact of TB stigma(s)? Each theme was further subdivided into research topics to be addressed to move the agenda forward. These include more clarity on what causes TB stigmas to emerge and thrive, the difficulty of measuring the complexity of stigma, and the improbability of a universal stigma ‘cure’. Notwithstanding, these challenges should not hinder investments in TB stigma measurement and reduction. We believe it is time to focus on how and not whether the global community should measure and reduce TB stigma.Peer reviewedFinal Published versio

    TB hackathon : development and comparison of five models to predict subnational tuberculosis prevalence in Pakistan

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    Pakistan's national tuberculosis control programme (NTP) is among the many programmes worldwide that value the importance of subnational tuberculosis (TB) burden estimates to support disease control efforts, but do not have reliable estimates. A hackathon was thus organised to solicit the development and comparison of several models for small area estimation of TB. The TB hackathon was launched in April 2019. Participating teams were requested to produce district-level estimates of bacteriologically positive TB prevalence among adults (over 15 years of age) for 2018. The NTP provided case-based data from their 2010-2011 TB prevalence survey, along with data relating to TB screening, testing and treatment for the period between 2010-2011 and 2018. Five teams submitted district-level TB prevalence estimates, methodological details and programming code. Although the geographical distribution of TB prevalence varied considerably across models, we identified several districts with consistently low notification-to-prevalence ratios. The hackathon highlighted the challenges of generating granular spatiotemporal TB prevalence forecasts based on a cross-sectional prevalence survey data and other data sources. Nevertheless, it provided a range of approaches to subnational disease modelling. The NTP's use and plans for these outputs shows that, limitations notwithstanding, they can be valuable for programme planning

    Efficacy of an adjunctive brief psychodynamic psychotherapy to usual inpatient treatment of depression: rationale and design of a randomized controlled trial.

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    BACKGROUND: A few recent studies have found indications of the effectiveness of inpatient psychotherapy for depression, usually of an extended duration. However, there is a lack of controlled studies in this area and to date no study of adequate quality on brief psychodynamic psychotherapy for depression during short inpatient stay exists. The present article describes the protocol of a study that will examine the relative efficacy, the cost-effectiveness and the cost-utility of adding an Inpatient Brief Psychodynamic Psychotherapy to pharmacotherapy and treatment-as-usual for inpatients with unipolar depression. METHODS/DESIGN: The study is a one-month randomized controlled trial with a two parallel group design and a 12-month naturalistic follow-up. A sample of 130 consecutive adult inpatients with unipolar depression and Montgomery-Asberg Depression Rating Scale score over 18 will be recruited. The study is carried out in the university hospital section for mood disorders in Lausanne, Switzerland. Patients are assessed upon admission, and at 1-, 3- and 12- month follow-ups. Inpatient therapy is a manualized brief intervention, combining the virtues of inpatient setting and of time-limited dynamic therapies (focal orientation, fixed duration, resource-oriented interventions). Treatment-as-usual represents the best level of practice for a minimal treatment condition usually proposed to inpatients. Final analyses will follow an intention-to-treat strategy. Depressive symptomatology is the primary outcome and secondary outcome includes measures of psychiatric symptomatology, psychosocial role functioning, and psychodynamic-emotional functioning. The mediating role of the therapeutic alliance is also examined. Allocation to treatment groups uses a stratified block randomization method with permuted block. To guarantee allocation concealment, randomization is done by an independent researcher. DISCUSSION: Despite the large number of studies on treatment of depression, there is a clear lack of controlled research in inpatient psychotherapy during the acute phase of a major depressive episode. Research on brief therapy is important to take into account current short lengths of stay in psychiatry. The current study has the potential to scientifically inform appropriate inpatient treatment. This study is the first to address the issue of the economic evaluation of inpatient psychotherapy. TRIAL REGISTRATION: Australian New Zealand Clinical Trial Registry (ACTRN12612000909820)

    Pilocarpine-Induced Status Epilepticus in Rats Involves Ischemic and Excitotoxic Mechanisms

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    The neuron loss characteristic of hippocampal sclerosis in temporal lobe epilepsy patients is thought to be the result of excitotoxic, rather than ischemic, injury. In this study, we assessed changes in vascular structure, gene expression, and the time course of neuronal degeneration in the cerebral cortex during the acute period after onset of pilocarpine-induced status epilepticus (SE). Immediately after 2 hr SE, the subgranular layers of somatosensory cortex exhibited a reduced vascular perfusion indicative of ischemia, whereas the immediately adjacent supragranular layers exhibited increased perfusion. Subgranular layers exhibited necrotic pathology, whereas the supergranular layers were characterized by a delayed (24 h after SE) degeneration apparently via programmed cell death. These results indicate that both excitotoxic and ischemic injuries occur during pilocarpine-induced SE. Both of these degenerative pathways, as well as the widespread and severe brain damage observed, should be considered when animal model-based data are compared to human pathology
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