94 research outputs found

    Particle Detection Algorithms for Complex Plasmas

    Full text link
    In complex plasmas, the behavior of freely floating micrometer sized particles is studied. The particles can be directly visualized and recorded by digital video cameras. To analyze the dynamics of single particles, reliable algorithms are required to accurately determine their positions to sub-pixel accuracy from the recorded images. Typically, straightforward algorithms are used for this task. Here, we combine the algorithms with common techniques for image processing. We study several algorithms and pre- and post-processing methods, and we investigate the impact of the choice of threshold parameters, including an automatic threshold detection. The results quantitatively show that each algorithm and method has its own advantage, often depending on the problem at hand. This knowledge is applicable not only to complex plasmas, but useful for any kind of comparable image-based particle tracking, e.g. in the field of colloids or granular matter

    MANAGEMENT OF DEPRESSION IN THE PRESENCE OF PAIN SYMPTOMS

    Get PDF
    Somatic illness is frequently associated with depression and anxiety and major depression significantly increases risk of severe medical conditions, e.g. cardiovascular illness. One of the most frequent comorbidities is that of depression and pain. Alterations in or adrenergic and serotonergic neurotransmissions in the central nervous system have been implicated in the joint pathophysiology of depression and chronic pain. Antidepressants, alone or in combination with psychotherapy, are an effective treatment option in such cases. The newer dual action antidepressants (milnacipran, venlafaxine, duloxetine) acting specifically on both noradrenergic and serotonergic neurotransmitter systems are presumably more reliable in pain management. So far, the most extensively studied drug has been duloxetine. Twelve randomized placebo-controlled trials with the total number of 4,108 patients suffering from pain associated with major depressive disorder suggested consistent analgesic efficacy of duloxetine, especially in fibromyalgia and peripheral neuropathic pain

    A new rotational thrombectomy catheter: System design and first clinical experiences

    Get PDF
    Purpose: To describe a new catheter for the percutaneous mechanical removal of fresh and organized thrombi, and to assess its efficacy and safety in vitro and in vivo. Methods: The catheter consists of a coated stainless steel spiral that rotates at 40,000 rpm over a guidewire inside the whole length of an 8 Fr, single-lumen, polyurethane catheter, driving a dual-blade cutting crown. Abraded occlusion material is sucked into the catheter head through distal side holes and transported by the spiral into a reservoir at the proximal end. The efficacy of the device was tested in arterial models and fresh bovine carotid arteries (n=72). In a clinical pilot study 10 patients (8 women, 2 men; mean age 70.6 ±10.1 years) with occlusions of the superficial femoral artery (2-12 cm, mean 5.8 cm), not older than 4 weeks, underwent thrombectomy with the new catheter. Results: In arterial models and bovine cadaver arteries the catheter completely removed fresh thrombi. Occlusion material of higher consistency was cut into particles of 100-500 μm and transported outside. Thrombectomy was successful and vessel patency restored in all 10 patients. The ankle/brachial pressure index significantly (p<0.0005) increased from 0.41±0.18 before intervention to 0.88±0.15 after 48 hr and to 0.84±0.20 after 3 months. Two reocclusions occurred within 14 days after the intervention. Conclusion: Thrombectomy with the new device appears to be feasible and safe in patients with acute and subacute occlusions of the femoropopliteal arter

    MANAGEMENT OF DEPRESSION IN THE PRESENCE OF PAIN SYMPTOMS

    Get PDF
    Somatic illness is frequently associated with depression and anxiety and major depression significantly increases risk of severe medical conditions, e.g. cardiovascular illness. One of the most frequent comorbidities is that of depression and pain. Alterations in or adrenergic and serotonergic neurotransmissions in the central nervous system have been implicated in the joint pathophysiology of depression and chronic pain. Antidepressants, alone or in combination with psychotherapy, are an effective treatment option in such cases. The newer dual action antidepressants (milnacipran, venlafaxine, duloxetine) acting specifically on both noradrenergic and serotonergic neurotransmitter systems are presumably more reliable in pain management. So far, the most extensively studied drug has been duloxetine. Twelve randomized placebo-controlled trials with the total number of 4,108 patients suffering from pain associated with major depressive disorder suggested consistent analgesic efficacy of duloxetine, especially in fibromyalgia and peripheral neuropathic pain

    Ekoplasma - The Future of Complex Plasma Research in aboard the International Space Station

    Get PDF
    Ekoplasma is a joint German-Russian project, developing the future multi-purpose laboratory for the investigation of complex plasmas under microgravity conditions aboard the International Space Station (ISS). Complex plasmas are low-temperature plasmas, consisting of neutral gas atoms, ions, electrons and micro-meter sized particles as an additional component. The particles become charged in the plasma and as a result of their mutual repulsion form an optically thin cloud that can be studied in its full spatial and dynamical complexity on the granularity scale of each particle by optical cameras. Therefore, complex plasmas allow fundamental investigations down to the kinetic level of individual particles also for a wide field of interdisciplinary topics in classical condensed matter physics. Since gravity prevents the formation of large, homogeneous systems on earth, research on the ISS is essential, and Ekoplasma will follow in a line of successful preceding experiments aboard the ISS: PKE-Nefedov, PK-3 Plus and the currently operating PK-4 facility. Ekoplasma is planned to be launched to the ISS in 2022, and it will cover a wide range of research topics such as solidification and melting, phase separation in binary systems, the transition to turbulence, active matter or electrorheology

    Affective state and voice: cross-cultural assessment of speaking behavior and voice sound characteristics - a normative multicenter study of 577 + 36 healthy subjects

    Get PDF
    Human speech is greatly influenced by the speakers’ affective state, such as sadness, happiness, grief, guilt, fear, anger, aggression, faintheartedness, shame, sexual arousal, love, amongst others. Attentive listeners discover a lot about the affective state of their dialog partners with no great effort, and without having to talk about it explicitly during a conversation or on the phone. On the other hand, speech dysfunctions, such as slow, delayed or monotonous speech, are prominent features of affective disorders. This project was comprised of 4 studies with healthy volunteers from Bristol (English: n=117), Lausanne (French: n=128), Zurich (German: n=208), and Valencia (Spanish: n=124). All samples were stratified according to gender, age, and education. The specific study design with different types of spoken text along with repeated assessments at 14-day intervals allowed us to estimate the “natural” variation of speech parameters over time, and to analyze the sensitivity of speech parameters with respect to form and content of spoken text. Additionally, our project included a longitudinal self-assessment study with university students from Zurich (n=18) and unemployed adults from Valencia (n=18) in order to test the feasibility of the speech analysis method in home environments. The normative data showed that speaking behavior and voice sound characteristics can be quantified in a reproducible and language-independent way. The high resolution of the method was verified by a computerized assignment of speech parameter patterns to languages at a success rate of 90%, while the correct assignment to texts was 70%. In the longitudinal self-assessment study we calculated individual “baselines” for each test person along with deviations thereof. The significance of such deviations was assessed through the normative reference data. Our data provided gender-, age-, and language-specific thresholds that allow one to reliably distinguish between “natural fluctuations” and “significant changes”. The longitudinal self-assessment study with repeated assessments at 1-day intervals over 14 days demonstrated the feasibility and efficiency of the speech analysis method in home environments, thus clearing the way to a broader range of applications in psychiatry

    Randomized trial of intermittent intraputamenal glial cell line-derived neurotrophic factor in Parkinson's disease

    Get PDF
    We investigated the effects of glial cell line-derived neurotrophic factor (GDNF) in Parkinson’s disease, using intermittent intraputamenal convection-enhanced delivery via a skull-mounted transcutaneous port as a novel administration paradigm to potentially afford putamen-wide therapeutic delivery. This was a single-centre, randomized, double-blind, placebo-controlled trial. Patients were 35–75 years old, had motor symptoms for 5 or more years, and presented with moderate disease severity in the OFF state [Hoehn and Yahr stage 2–3 and Unified Parkinson’s Disease Rating Scale motor score (part III) (UPDRS-III) between 25 and 45] and motor fluctuations. Drug delivery devices were implanted and putamenal volume coverage was required to exceed a predefined threshold at a test infusion prior to randomization. Six pilot stage patients (randomization 2:1) and 35 primary stage patients (randomization 1:1) received bilateral intraputamenal infusions of GDNF (120 mg per putamen) or placebo every 4 weeks for 40 weeks. Efficacy analyses were based on the intention-to-treat principle and included all patients randomized. The primary outcome was the percentage change from baseline to Week 40 in the OFF state (UPDRS-III). The primary analysis was limited to primary stage patients, while further analyses included all patients from both study stages. The mean OFF state UPDRS motor score decreased by 17.3 17.6% in the active group and 11.8 15.8% in the placebo group (least squares mean difference: 4.9%, 95% CI: 16.9, 7.1, P = 0.41). Secondary endpoints did not show significant differences between the groups either. A post hoc analysis found nine (43%) patients in the active group but no placebo patients with a large clinically important motor improvement (510 points) in the OFF state (P = 0.0008). 18F-DOPA PET imaging demonstrated a significantly increased uptake throughout the putamen only in the active group, ranging from 25% (left anterior putamen; P = 0.0009) to 100% (both posterior putamina; P50.0001). GDNF appeared to be well tolerated and safe, and no drug-related serious adverse events were reported. The study did not meet its primary endpoint. 18F-DOPA imaging, however, suggested that intermittent convection-enhanced delivery of GDNF produced a putamen-wide tissue engagement effect, overcoming prior delivery limitations. Potential reasons for not proving clinical benefit at 40 weeks are discussed

    Perinatal and 2-year neurodevelopmental outcome in late preterm fetal compromise: the TRUFFLE 2 randomised trial protocol

    Get PDF
    Introduction: Following the detection of fetal growth restriction, there is no consensus about the criteria that should trigger delivery in the late preterm period. The consequences of inappropriate early or late delivery are potentially important yet practice varies widely around the world, with abnormal findings from fetal heart rate monitoring invariably leading to delivery. Indices derived from fetal cerebral Doppler examination may guide such decisions although there are few studies in this area. We propose a randomised, controlled trial to establish the optimum method of timing delivery between 32 weeks and 36 weeks 6 days of gestation. We hypothesise that delivery on evidence of cerebral blood flow redistribution reduces a composite of perinatal poor outcome, death and short-term hypoxia-related morbidity, with no worsening of neurodevelopmental outcome at 2 years. Methods and analysis: Women with non-anomalous singleton pregnancies 32+0 to 36+6 weeks of gestation in whom the estimated fetal weight or abdominal circumference is &lt;10th percentile or has decreased by 50 percentiles since 18-32 weeks will be included for observational data collection. Participants will be randomised if cerebral blood flow redistribution is identified, based on umbilical to middle cerebral artery pulsatility index ratio values. Computerised cardiotocography (cCTG) must show normal fetal heart rate short term variation (≥4.5 msec) and absence of decelerations at randomisation. Randomisation will be 1:1 to immediate delivery or delayed delivery (based on cCTG abnormalities or other worsening fetal condition). The primary outcome is poor condition at birth and/or fetal or neonatal death and/or major neonatal morbidity, the secondary non-inferiority outcome is 2-year infant general health and neurodevelopmental outcome based on the Parent Report of Children's Abilities-Revised questionnaire. Ethics and dissemination: The Study Coordination Centre has obtained approval from London-Riverside Research Ethics Committee (REC) and Health Regulatory Authority (HRA). Publication will be in line with NIHR Open Access policy. Trial registration number: Main sponsor: Imperial College London, Reference: 19QC5491. Funders: NIHR HTA, Reference: 127 976. Study coordination centre: Imperial College Healthcare NHS Trust, Du Cane Road, London, W12 0HS with Centre for Trials Research, College of Biomedical &amp; Life Sciences, Cardiff University. IRAS Project ID: 266 400. REC reference: 20/LO/0031. ISRCTN registry: 76 016 200

    Extended Treatment with Glial Cell Line-Derived Neurotrophic Factor in Parkinson's Disease

    Get PDF
    Background: Intraputamenal glial cell line-derived neurotrophic factor (GDNF), administered every 4 weeks to patients with moderately advanced Parkinson’s disease, did not show significant clinical improvements against placebo at 40 weeks, although it significantly increased [18F]DOPA uptake throughout the entire putamen. Objective: This open-label extension study explored the effects of continued (prior GDNF patients) or new (prior placebo patients) exposure to GDNF for another 40 weeks. Methods: Using the infusion protocol of the parent study, all patients received GDNF without disclosing prior treatment allocations (GDNF or placebo). The primary outcome was the percentage change from baseline to Week 80 in the OFF state Unified Parkinson’s Disease Rating Scale (UPDRS) motor score. Results: All 41 parent study participants were enrolled. The primary outcome decreased by 26.7±20.7% in patients on GDNF for 80 weeks (GDNF/GDNF; N = 21) and 27.6±23.6% in patients on placebo for 40 weeks followed by GDNF for 40 weeks (placebo/GDNF, N = 20; least squares mean difference: 0.4%, 95% CI: –13.9, 14.6, p = 0.96). Secondary endpoints did not show significant differences between the groups at Week 80 either. Prespecified comparisons between GDNF/GDNF at Week 80 and placebo/GDNF at Week 40 showed significant differences for mean OFF state UPDRS motor (–9.6±6.7 vs. –3.8±4.2 points, p = 0.0108) and activities of daily living score (–6.9±5.5 vs. –1.0±3.7 points, p = 0.0003). No treatment-emergent safety concerns were identified. Conclusions: The aggregate study results, from the parent and open-label extension suggest that future testing with GDNF will likely require an 80- rather than a 40-week randomized treatment period and/or a higher dose

    Search for single production of vector-like quarks decaying into Wb in pp collisions at s=8\sqrt{s} = 8 TeV with the ATLAS detector

    Get PDF
    corecore