910 research outputs found
Atmospheric Conditions Associated with Lightning during Snow and Ice Events
The purpose of this research was to find the atmospheric mechanisms associated with lightning in snow and ice events. The specific mechanisms that were examined were low-level wind shear, upper level divergence, surface temperature, low-level temperature, the -10 ° C level, and precipitable water. A chi-squared dependency test showed the strong association of low-level wind shear to each precipitation type (snow, sleet/freezing rain, rain) in two separate studies. Surface temperature appeared to have a relationship to lightning in all precipitation categories, while no significant relationship to lightning in all precipitation categories, while no significant relationship was found with upper level divergence, the -10 ° C level, or the precipitable water. From examination of the vertical soundings, temperatures above freezing are found in the low levels for all precipitation types meaning that different types of hydrometeors are present in the clouds. The mixing of these due to the turbulent effects of low-level shear may explain how the thunderclouds (mostly stratiform) are charged. Graupel and snow pellet interaction are also believed to be mechanisms for cloud charging
Ammonia: what adult neurologists need to know
Hyperammonaemia is often encountered in acute neurology and can be the cause of acute or chronic neurological symptoms. Patients with hyperammonaemia may present with seizures or encephalopathy, or may be entirely asymptomatic. The underlying causes are diverse but often straightforward to diagnose, although sometimes require specialist investigations. Haemodialysis or haemo(dia)filtration is the first-line treatment for acute severe hyperammonaemia (of any cause) in an adult. Here we discuss our approach to adult patients with hyperammonaemia identified by a neurologist
Oxygen-Independent Stabilization of Hypoxia Inducible Factor (HIF)-1 during RSV Infection
BACKGROUND: Hypoxia-inducible factor 1 (HIF)-1alpha is a transcription factor that functions as master regulator of mammalian oxygen homeostasis. In addition, recent studies identified a role for HIF-1alpha as transcriptional regulator during inflammation or infection. Based on studies showing that respiratory syncytial virus (RSV) is among the most potent biological stimuli to induce an inflammatory milieu, we hypothesized a role of HIF-1alpha as transcriptional regulator during infections with RSV. METHODOLOGY, PRINCIPAL FINDINGS: We gained first insight from immunohistocemical studies of RSV-infected human pulmonary epithelia that were stained for HIF-1alpha. These studies revealed that RSV-positive cells also stained for HIF-1alpha, suggesting concomitant HIF-activation during RSV infection. Similarly, Western blot analysis confirmed an approximately 8-fold increase in HIF-1alpha protein 24 h after RSV infection. In contrast, HIF-1alpha activation was abolished utilizing UV-treated RSV. Moreover, HIF-alpha-regulated genes (VEGF, CD73, FN-1, COX-2) were induced with RSV infection of wild-type cells. In contrast, HIF-1alpha dependent gene induction was abolished in pulmonary epithelia following siRNA mediated repression of HIF-1alpha. Measurements of the partial pressure of oxygen in the supernatants of RSV infected epithelia or controls revealed no differences in oxygen content, suggesting that HIF-1alpha activation is not caused by RSV associated hypoxia. Finally, studies of RSV pneumonitis in mice confirmed HIF-alpha-activation in a murine in vivo model. CONCLUSIONS/SIGNIFICANCE: Taking together, these studies suggest hypoxia-independent activation of HIF-1alpha during infection with RSV in vitro and in vivo
Regulatory T-cell deficiency leads to features of autoimmune liver disease overlap syndrome in scurfy mice
Scurfy mice have a complete deficiency of functional regulatory T cells (Treg) due to a frameshift mutation in the Foxp3 gene. The impaired immune homeostasis results in a lethal lymphoproliferative disorder affecting multiple organs, including the liver. The autoimmune pathology in scurfy mice is in part accompanied by autoantibodies such as antinuclear antibodies (ANA). ANA are serological hallmarks of several autoimmune disorders including autoimmune liver diseases (AILD). However, the underlying pathogenesis and the role of Treg in AILD remain to be elucidated. The present study therefore aimed to characterize the liver disease in scurfy mice
A portable 3D Imaging FMCW MIMO Radar Demonstrator with a 24x24 Antenna Array for Medium Range Applications
© 2018 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Multiple-input multiple-output (MIMO) radars
have been shown to improve target detection for surveillance
applications thanks to their proven high-performance properties.
In this paper, the design, implementation, and results of a
complete 3-D imaging frequency-modulated continuous-wave
MIMO radar demonstrator are presented. The radar sensor
working frequency range spans between 16 and 17 GHz,
and the proposed solution is based on a 24-transmitter and
24-receiver MIMO radar architecture, implemented by timedivision
multiplexing of the transmit signals. A modular approach
based on conventional low-cost printed circuit boards is used
for the transmit and receive systems. Using digital beamforming
algorithms and radar processing techniques on the received
signals, a high-resolution 3-D sensing of the range, azimuth, and
elevation can be calculated. With the current antenna configuration,
an angular resolution of 2.9° can be reached. Furthermore,
by taking advantage of the 1-GHz bandwidth of the system,
a range resolution of 0.5 m is achieved. The radio-frequency
front-end, digital system and radar signal processing units are
here presented. The medium-range surveillance potential and
the high-resolution capabilities of the MIMO radar are proved
with results in the form of radar images captured from the field
measurements.Ganis, A.; Miralles-Navarro, E.; Schoenlinner, B.; Prechtel, U.; Meusling, A.; Heller, C.; Spreng, T.... (2018). A portable 3D Imaging FMCW MIMO Radar Demonstrator with a 24x24 Antenna Array for Medium Range Applications. IEEE Transactions on Geoscience and Remote Sensing. 56(1):298-312. https://doi.org/10.1109/TGRS.2017.2746739S29831256
Machine Learning Outperforms Regression Analysis to Predict Next-Season Major League Baseball Player Injuries: Epidemiology and Validation of 13,982 Player-Years From Performance and Injury Profile Trends, 2000-2017
Background: Machine learning (ML) allows for the development of a predictive algorithm capable of imbibing historical data on a Major League Baseball (MLB) player to accurately project the player\u27s future availability.
Purpose: To determine the validity of an ML model in predicting the next-season injury risk and anatomic injury location for both position players and pitchers in the MLB.
Study Design: Descriptive epidemiology study.
Methods: Using 4 online baseball databases, we compiled MLB player data, including age, performance metrics, and injury history. A total of 84 ML algorithms were developed. The output of each algorithm reported whether the player would sustain an injury the following season as well as the injury\u27s anatomic site. The area under the receiver operating characteristic curve (AUC) primarily determined validation.
Results: Player data were generated from 1931 position players and 1245 pitchers, with a mean follow-up of 4.40 years (13,982 player-years) between the years of 2000 and 2017. Injured players spent a total of 108,656 days on the disabled list, with a mean of 34.21 total days per player. The mean AUC for predicting next-season injuries was 0.76 among position players and 0.65 among pitchers using the top 3 ensemble classification. Back injuries had the highest AUC among both position players and pitchers, at 0.73. Advanced ML models outperformed logistic regression in 13 of 14 cases.
Conclusion: Advanced ML models generally outperformed logistic regression and demonstrated fair capability in predicting publicly reportable next-season injuries, including the anatomic region for position players, although not for pitchers
Tomographic diffractive microscopy: towards highresolution 3-D real-time data acquisition, image reconstruction and display of unlabeled samples
Tomographic diffractive microscopy allows for imaging unlabeled specimens, with a better resolution than conventional microscopes, giving access to the index of refraction distribution within the specimen, and possibly at high speed. Principles of image formation and reconstruction are presented, and progresses towards realtime, three-dimensional acquisition, image reconstruction and final display, are discussed
Scurfy Mice Develop Features of Connective Tissue Disease Overlap Syndrome and Mixed Connective Tissue Disease in the Absence of Regulatory T Cells
Due to a missense mutation in the Foxp3 gene, scurfy mice are deficient in functional regulatory T cells (Treg). The consequent loss of peripheral tolerance manifests itself by fatal autoimmune mediated multi-organ disease. Previous studies have outlined the systemic inflammatory disease and demonstrated production of anti-nuclear antibodies (ANA) in scurfy mice. However, specific autoantibody targets remained to be defined. ANA are immunological markers for several connective tissue diseases (CTD) and target a large number of intracellular molecules. Therefore, we examined scurfy sera for the presence of different ANA specificities and further assessed the organ involvement in these animals. Indirect immunofluorescence was used as a screen for ANA in the sera of scurfy mice and dilutions of 1/100 were considered positive. Addressable laser bead immunoassays (ALBIA) were used to detect specific autoantibody targets. Subsequent histological tissue evaluation was verified by hematoxylin and eosin (H&E) staining. In our study, we observed that nearly all scurfy mice produced ANA. The most prevalent pattern in scurfy sera was nuclear coarse speckled, also known as the AC-5 pattern according to the International Consensus on ANA Patterns. U1-ribonucleoprotein (U1RNP) was found to be the most common target antigen recognized by autoantibodies in scurfy mice. Additionally, scurfy mice exhibited a mild myositis with histological characteristics similar to polymyositis/dermatomyositis. Myopathy-specific autoantibody profile revealed significantly increased levels of anti-SMN (survival of motor neuron) as well as anti-Gemin3 antibodies in scurfy sera. Overall, we demonstrate that the impaired peripheral tolerance in the absence of regulatory T cells in scurfy mice is associated with features of mixed connective tissue disease (MCTD). This includes, along with our previous findings, very high titers of anti-U1RNP antibodies and an inflammatory myopathy
Event-triggered logical flow control for comprehensive process integration of multi-step assays on centrifugal microfluidic platforms
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.The centrifugal "lab-on-a-disc" concept has proven to have great potential for process integration of bioanalytical assays, in particular where ease-of-use, ruggedness, portability, fast turn-around time and cost efficiency are of paramount importance. Yet, as all liquids residing on the disc are exposed to the same centrifugal field, an inherent challenge of these systems remains the automation of multi-step, multi-liquid sample processing and subsequent detection. In order to orchestrate the underlying bioanalytical protocols, an ample palette of rotationally and externally actuated valving schemes has been developed. While excelling with the level of flow control, externally actuated valves require interaction with peripheral instrumentation, thus compromising the conceptual simplicity of the centrifugal platform. In turn, for rotationally controlled schemes, such as common capillary burst valves, typical manufacturing tolerances tend to limit the number of consecutive laboratory unit operations (LUOs) that can be automated on a single disc. In this paper, a major advancement on recently established dissolvable film (DF) valving is presented; for the very first time, a liquid handling sequence can be controlled in response to completion of preceding liquid transfer event, i.e. completely independent of external stimulus or changes in speed of disc rotation. The basic, event-triggered valve configuration is further adapted to leverage conditional, large-scale process integration. First, we demonstrate a fluidic network on a disc encompassing 10 discrete valving steps including logical relationships such as an AND-conditional as well as serial and parallel flow control. Then we present a disc which is capable of implementing common laboratory unit operations such as metering and selective routing of flows. Finally, as a pilot study, these functions are integrated on a single disc to automate a common, multi-step lab protocol for the extraction of total RNA from mammalian cell homogenate.Peer reviewe
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