297 research outputs found
Presynaptic Autoinhibition of Central Noradrenaline Release in Vitro: Operational Characteristics and Effects of Drugs Acting at Alpha-2 Adrenoceptors in the Presence of Uptake Inhibition1
ABSTRAC
Testing characteristics of grid forming converters part III : inertial behaviour
On the path towards an energy system powered entirely by Renewable Energy Sources (RES), power electronic converters will have to take over more and more functionalities from synchronous generators to ensure a stable and secure operation of the power grid. Moreover, it is widely recognised that the use of Grid Forming Converters (GFC) is necessary to fully meet these requirements. Over the last years, different concepts have been developed to achieve grid forming characteristics of static power converters. The next essential step is to agree on an exact definition and specification of GFC electrical behaviour as well as to define a suitable conformity assessment procedure. For this purpose, standardised testing guidelines for GFC are needed to assess those functionalities, which are relevant for dynamic grid stability. As a British-German joint work of the two research projects Battery-VSM and VerbundnetzStabil, the first draft of such guidelines is being currently developed. One of the necessary characteristics which makes converter a GFC is its ability to provide inertial response during the dynamic frequency changes in the system. This paper focuses on how to demonstrate and quantify an inertia-equivalent behaviour of a GFC. The response to a transient system event is quantified in terms of a damping factor D as well as an equivalent inertia constant H. A few alternative methods are proposed for empirical estimation of those parameters accompanied by selected laboratory test results and practical considerations
Dilepton Spectra from Decays of Light Unflavored Mesons
The invariant mass spectrum of the and pairs
from decays of light unflavored mesons with masses below the -meson mass to final states containing along with a dilepton pair one
photon, one meson, and two mesons are calculated within the framework of the
effective meson theory. The results can be used for simulations of the dilepton
spectra in heavy-ion collisions and for experimental searches of dilepton meson
decays.Comment: 73 pages, 19 figures, 3 tables, REVTeX, new references adde
Local topographic wetness indices predict household malaria risk better than land-use and land-cover in the western Kenya highlands
Acute wound management: revisiting the approach to assessment, irrigation, and closure considerations
Abstract
Background
As millions of emergency department (ED) visits each year include wound care, emergency care providers must remain experts in acute wound management. The variety of acute wounds presenting to the ED challenge the physician to select the most appropriate management to facilitate healing. A complete wound history along with anatomic and specific medical considerations for each patient provides the basis of decision making for wound management. It is essential to apply an evidence‐based approach and consider each wound individually in order to create the optimal conditions for wound healing.
Aims
A comprehensive evidence‐based approach to acute wound management is an essential skill set for any emergency physician or acute care practitioner. This review provides an overview of current evidence and addresses frequent pitfalls.
Methods
A systematic review of the literature for acute wound management was performed.
Results
A structured MEDLINE search was performed regarding acute wound management including established wound care guidelines. The data obtained provided the framework for evidence‐based recommendations and current best practices for wound care.
Conclusion
Acute wound management varies based on the wound location and characteristics. No single approach can be applied to all wounds; however, a systematic approach to acute wound care integrated with current best practices provides the framework for exceptional wound management
First Measurement of Gamma(D*+) and Precision Measurement of m_D*+ - m_D0
We present the first measurement of the D*+ width using 9/fb of e+ e- data
collected near the Upsilon(4S) resonance by the CLEO II.V detector. Our method
uses advanced tracking techniques and a reconstruction method that takes
advantage of the small vertical size of the CESR beam spot to measure the
energy release distribution from the D*+ -> D0 pi+ decay. We find Gamma(D*+) =
96 +- 4 (Statistical) +- 22 (Systematic) keV. We also measure the energy
release in the decay and compute Delta m = m(D*+) - m(D0) = 145.412 +- 0.002
(Statistical) +- 0.012 (Systematic) MeV/c^2Comment: 24 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, submitted to PR
Identification of TNF-alpha-Responsive Promoters and Enhancers in the Intestinal Epithelial Cell Model Caco-2
The Caco-2 cell line is one of the most important in vitro models for enterocytes, and is used to study drug absorption and disease, including inflammatory bowel disease and cancer. In order to use the model optimally, it is necessary to map its functional entities. In this study, we have generated genome-wide maps of active transcription start sites (TSSs), and active enhancers in Caco-2 cells with or without tumour necrosis factor (TNF)-α stimulation to mimic an inflammatory state. We found 520 promoters that significantly changed their usage level upon TNF-α stimulation; of these, 52% are not annotated. A subset of these has the potential to confer change in protein function due to protein domain exclusion. Moreover, we locate 890 transcribed enhancer candidates, where ∼50% are changing in usage after TNF-α stimulation. These enhancers share motif enrichments with similarly responding gene promoters. As a case example, we characterize an enhancer regulating the laminin-5 γ2-chain (LAMC2) gene by nuclear factor (NF)-κB binding. This report is the first to present comprehensive TSS and enhancer maps over Caco-2 cells, and highlights many novel inflammation-specific promoters and enhancers
Short Conduction Delays Cause Inhibition Rather than Excitation to Favor Synchrony in Hybrid Neuronal Networks of the Entorhinal Cortex
How stable synchrony in neuronal networks is sustained in the presence of conduction delays is an open question. The Dynamic Clamp was used to measure phase resetting curves (PRCs) for entorhinal cortical cells, and then to construct networks of two such neurons. PRCs were in general Type I (all advances or all delays) or weakly type II with a small region at early phases with the opposite type of resetting. We used previously developed theoretical methods based on PRCs under the assumption of pulsatile coupling to predict the delays that synchronize these hybrid circuits. For excitatory coupling, synchrony was predicted and observed only with no delay and for delays greater than half a network period that cause each neuron to receive an input late in its firing cycle and almost immediately fire an action potential. Synchronization for these long delays was surprisingly tight and robust to the noise and heterogeneity inherent in a biological system. In contrast to excitatory coupling, inhibitory coupling led to antiphase for no delay, very short delays and delays close to a network period, but to near-synchrony for a wide range of relatively short delays. PRC-based methods show that conduction delays can stabilize synchrony in several ways, including neutralizing a discontinuity introduced by strong inhibition, favoring synchrony in the case of noisy bistability, and avoiding an initial destabilizing region of a weakly type II PRC. PRCs can identify optimal conduction delays favoring synchronization at a given frequency, and also predict robustness to noise and heterogeneity
The Small Satellites of Pluto as Observed by New Horizons
The New Horizons mission has provided resolved measurements of Pluto's moons
Styx, Nix, Kerberos, and Hydra. All four are small, with equivalent spherical
diameters of 40 km for Nix and Hydra and ~10 km for Styx and Kerberos.
They are also highly elongated, with maximum to minimum axis ratios of
2. All four moons have high albedos ( 50-90 %) suggestive of
a water-ice surface composition. Crater densities on Nix and Hydra imply
surface ages 4 Ga. The small moons rotate much faster than
synchronous, with rotational poles clustered nearly orthogonal to the common
pole directions of Pluto and Charon. These results reinforce the hypothesis
that the small moons formed in the aftermath of a collision that produced the
Pluto-Charon binary.Comment: in Science 351, aae0030 (2016
Discrepancies between dimensions of interoception in autism: implications for emotion and anxiety
Emotions and affective feelings are influenced by one's internal state of bodily arousal via interoception. Autism Spectrum Conditions (ASC) are associated with difficulties in recognising others' emotions, and in regulating own emotions. We tested the hypothesis that, in people with ASC, such affective differences may arise from abnormalities in interoceptive processing. We demonstrated that individuals with ASC have reduced interoceptive accuracy (quantified using heartbeat detection tests) and exaggerated interoceptive sensibility (subjective sensitivity to internal sensations on self-report questionnaires), reflecting an impaired ability to objectively detect bodily signals alongside an over-inflated subjective perception of bodily sensations. The divergence of these two interoceptive axes can be computed as a trait prediction error. This error correlated with deficits in emotion sensitivity and occurrence of anxiety symptoms. Our results indicate an origin of emotion deficits and affective symptoms in ASC at the interface between body and mind, specifically in expectancy-driven interpretation of interoceptive information
- …