387 research outputs found
Latent Dirichlet Allocation Uncovers Spectral Characteristics of Drought Stressed Plants
Understanding the adaptation process of plants to drought stress is essential
in improving management practices, breeding strategies as well as engineering
viable crops for a sustainable agriculture in the coming decades.
Hyper-spectral imaging provides a particularly promising approach to gain such
understanding since it allows to discover non-destructively spectral
characteristics of plants governed primarily by scattering and absorption
characteristics of the leaf internal structure and biochemical constituents.
Several drought stress indices have been derived using hyper-spectral imaging.
However, they are typically based on few hyper-spectral images only, rely on
interpretations of experts, and consider few wavelengths only. In this study,
we present the first data-driven approach to discovering spectral drought
stress indices, treating it as an unsupervised labeling problem at massive
scale. To make use of short range dependencies of spectral wavelengths, we
develop an online variational Bayes algorithm for latent Dirichlet allocation
with convolved Dirichlet regularizer. This approach scales to massive datasets
and, hence, provides a more objective complement to plant physiological
practices. The spectral topics found conform to plant physiological knowledge
and can be computed in a fraction of the time compared to existing LDA
approaches.Comment: Appears in Proceedings of the Twenty-Eighth Conference on Uncertainty
in Artificial Intelligence (UAI2012
SmartTrack: Efficient Predictive Race Detection
Widely used data race detectors, including the state-of-the-art FastTrack
algorithm, incur performance costs that are acceptable for regular in-house
testing, but miss races detectable from the analyzed execution. Predictive
analyses detect more data races in an analyzed execution than FastTrack
detects, but at significantly higher performance cost.
This paper presents SmartTrack, an algorithm that optimizes predictive race
detection analyses, including two analyses from prior work and a new analysis
introduced in this paper. SmartTrack's algorithm incorporates two main
optimizations: (1) epoch and ownership optimizations from prior work, applied
to predictive analysis for the first time; and (2) novel conflicting critical
section optimizations introduced by this paper. Our evaluation shows that
SmartTrack achieves performance competitive with FastTrack-a qualitative
improvement in the state of the art for data race detection.Comment: Extended arXiv version of PLDI 2020 paper (adds Appendices A-E) #228
SmartTrack: Efficient Predictive Race Detectio
implementation of an in-house management routine
Background Coma of unknown origin is an emergency caused by a variety of
possibly life-threatening pathologies. Although lethality is high, there are
currently no generally accepted management guidelines. Methods We implemented
a new interdisciplinary standard operating procedure (SOP) for patients
presenting with non-traumatic coma of unknown origin. It includes a new in-
house triage process, a new alert call, a new composition of the clinical
response team and a new management algorithm (altogether termed “coma alarm”).
It is triggered by two simple criteria to be checked with out-of-hospital
emergency response teams before the patient arrives. A neurologist in
collaboration with an internal specialist leads the in-hospital team.
Collaboration with anaesthesiology, trauma surgery and neurosurgery is
organised along structured pathways that include standardised laboratory tests
and imaging. Patients were prospectively enrolled. We calculated response
times as well as sensitivity and false positive rates, thus proportions of
over- and undertriaged patients, as quality measures for the implementation in
the SOP. Results During 24 months after implementation, we identified 325
eligible patients. Sensitivity was 60 % initially (months 1–4), then
fluctuated between 84 and 94 % (months 5–24). Overtriage never exceeded 15 %
and undertriage could be kept low at a maximum of 11 % after a learning
period. We achieved a median door-to-CT time of 20 minutes. 85 % of patients
needed subsequent ICU treatment, 40 % of which required specialised neuro-
ICUs. Discussion Our results indicate that our new simple in-house triage
criteria may be sufficient to identify eligible patients before arrival. We
aimed at ensuring the fastest possible proceedings given high portions of
underlying time-sensitive neurological and medical pathologies while using all
available resources as purposefully as possible. Conclusions Our SOP may
provide an appropriate tool for efficient management of patients with non-
traumatic coma. Our results justify the assignment of the initial diagnostic
workup to neurologists and internal specialists in collaboration with
anaesthesiologists
Epstein–Barr virus-encoded microRNA miR-BART2 down-regulates the viral DNA polymerase BALF5
MicroRNAs (miRNAs) have been implicated in sequence-specific cleavage, translational repression or deadenylation of specific target mRNAs resulting in post-transcriptional gene silencing. Epstein–Barr virus (EBV) encodes 23 miRNAs of unknown function. Here we show that the EBV-encoded miRNA miR-BART2 down-regulates the viral DNA polymerase BALF5. MiR-BART2 guides cleavage within the 3′-untranslated region (3′UTR) of BALF5 by virtue of its complete complementarity to its target. Induction of the lytic viral replication cycle results in a reduction of the level of miR-BART2 with a strong concomitant decrease of cleavage of the BALF5 3′UTR. Expression of miR-BART2 down-regulates the activity of a luciferase reporter gene containing the BALF5 3′UTR. Forced expression of miR-BART2 during lytic replication resulted in a 40–50% reduction of the level of BALF5 protein and a 20% reduction of the amount of virus released from EBV-infected cells. Our results are compatible with the notion that EBV-miR-BART2 inhibits transition from latent to lytic viral replication
Sensing Senses: Tactile Feedback for the Prevention of Decubitus Ulcers
Decubitus ulcers, also known as pressure sores, is a major problem in health care, in particular for patients with spinal cord injuries. These patients cannot feel the discomfort that would urge healthy people to change their posture. We describe a system that uses a sensor mat to detect problematic postures and provides tactile feedback to the user. The results of our preliminary study with healthy subjects show that the tactile feedback is a viable option to spoken feedback. We envision the system being used for rehabilitation games, but also for everyday Decubitus ulcers prevention
Guidelines of the International Headache Society for Controlled Clinical Trials in Cluster Headache
In 1995, a committee of the International Headache Society developed and published the first edition of the Guidelines for Controlled Trials of Drugs in Cluster Headache. These have not been revised. With the emergence of new medications, neuromodulation devices and trial designs, an updated version of the International Headache Society Guidelines for Controlled Clinical Trials in Cluster Headache is warranted. Given the scarcity of evidence-based data for cluster headache therapies, the update is largely consensus-based, but takes into account lessons learned from recent trials and demands by patients. It is intended to apply to both drug and neuromodulation treatments, with specific proposals for the latter when needed. The primary objective is to propose a template for designing high quality, state-of-the-art, controlled clinical trials of acute and preventive treatments in episodic and chronic cluster headache. The recommendations should not be regarded as dogma and alternative solutions to particular methodological problems should be explored in the future and scientifically validated
Functional Characterization of Aquaporin-4 Specific T Cells: Towards a Model for Neuromyelitis Optica
Antibodies to the water channel protein aquaporin-4 (AQP4), which is expressed in astrocytic endfeet at the blood brain barrier, have been identified in the serum of Neuromyelitis optica (NMO) patients and are believed to induce damage to astrocytes. However, AQP4 specific T helper cell responses that are required for the generation of anti-AQP4 antibodies and most likely also for the formation of intraparenchymal CNS lesions have not been characterized. specific T cells were present in the natural T cell repertoire of wild type C57BL/6 mice and T cell lines were raised. However, active immunization with these AQP4 peptides did not induce signs of spinal cord disease. Rather, sensitization with AQP4 peptides resulted in production of IFN-γ, but also IL-5 and IL-10 by antigen-specific T cells. Consistent with this cytokine profile, the AQP4 specific antibody response upon immunization with full length AQP4 included IgG1 and IgG2, which are associated with a mixed Th2/Th1 T cell response. restricted AQP4 specific T cell epitopes will allow us to investigate how AQP4 specific autoimmune reactions are regulated and to establish faithful mouse models of NMO that include both cellular and humoral responses against AQP4
New Strategies for Combining Mindfulness with Integrative Cognitive Behavioral Therapy for the Treatment of Generalized Anxiety Disorder
Generalized anxiety disorder (GAD) severely impacts social functioning, distress levels, and utilization of medical care compared with that of other major psychiatric disorders. Neither pharmacological nor psychotherapy interventions have adequately controlled cardinal symptoms of GAD: pervasive excessive anxiety and uncontrollable worry. Research has established cognitive behavioral therapy (CBT) as the most effective psychotherapy for controlling GAD; however, outcomes remain at only 50% reduction, with high relapse rates. Mindfulness has been integrated with CBT to treat people suffering from numerous psychiatric disorders, with mindfulness based stress reduction (MBSR) being the most researched. Preliminary evidence supports MBSR’s potential for controlling GAD symptoms and key researchers suggest mindfulness practices possess key elements for treating GAD. Classical mindfulness (CM) differs significantly from MBSR and possesses unique potentials for directly targeting process and state GAD symptoms inadequately treated by CBT. This article introduces the theory and practice of CM, its differences from MBSR, and a critical review of MBSR and CBT treatments for GAD. CM strategies designed to complement CBT targeting cardinal GAD symptoms are outlined with a case study illustrating its use
EEG Biofeedback as a Treatment for Substance Use Disorders: Review, Rating of Efficacy, and Recommendations for Further Research
Electroencephalographic (EEG) biofeedback has been employed in substance use disorder (SUD) over the last three decades. The SUD is a complex series of disorders with frequent comorbidities and EEG abnormalities of several types. EEG biofeedback has been employed in conjunction with other therapies and may be useful in enhancing certain outcomes of therapy. Based on published clinical studies and employing efficacy criteria adapted by the Association for Applied Psychophysiology and Biofeedback and the International Society for Neurofeedback and Research, alpha theta training—either alone for alcoholism or in combination with beta training for stimulant and mixed substance abuse and combined with residential treatment programs, is probably efficacious. Considerations of further research design taking these factors into account are discussed and descriptions of contemporary research are given
Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV
Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| < 0.03 at 95% confidence level. [Figure not available: see fulltext.
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