2,966 research outputs found
Exploring Replica-Exchange Wang-Landau sampling in higher-dimensional parameter space
We considered a higher-dimensional extension for the replica-exchange
Wang-Landau algorithm to perform a random walk in the energy and magnetization
space of the two-dimensional Ising model. This hybrid scheme combines the
advantages of Wang-Landau and Replica-Exchange algorithms, and the
one-dimensional version of this approach has been shown to be very efficient
and to scale well, up to several thousands of computing cores. This approach
allows us to split the parameter space of the system to be simulated into
several pieces and still perform a random walk over the entire parameter range,
ensuring the ergodicity of the simulation. Previous work, in which a similar
scheme of parallel simulation was implemented without using replica exchange
and with a different way to combine the result from the pieces, led to
discontinuities in the final density of states over the entire range of
parameters. From our simulations, it appears that the replica-exchange
Wang-Landau algorithm is able to overcome this difficulty, allowing exploration
of higher parameter phase space by keeping track of the joint density of
states.Comment: Proceedings of CCP2014 will appear in Journal of Physics: Conference
Series (JPCS), published by the IO
AMPA receptor anchoring at CA1 synapses is determined by N-terminal domain and TARP γ8 interactions.
AMPA receptor (AMPAR) abundance and positioning at excitatory synapses regulates the strength of transmission. Changes in AMPAR localisation can enact synaptic plasticity, allowing long-term information storage, and is therefore tightly controlled. Multiple mechanisms regulating AMPAR synaptic anchoring have been described, but with limited coherence or comparison between reports, our understanding of this process is unclear. Here, combining synaptic recordings from mouse hippocampal slices and super-resolution imaging in dissociated cultures, we compare the contributions of three AMPAR interaction domains controlling transmission at hippocampal CA1 synapses. We show that the AMPAR C-termini play only a modulatory role, whereas the extracellular N-terminal domain (NTD) and PDZ interactions of the auxiliary subunit TARP γ8 are both crucial, and each is sufficient to maintain transmission. Our data support a model in which γ8 accumulates AMPARs at the postsynaptic density, where the NTD further tunes their positioning. This interplay between cytosolic (TARP γ8) and synaptic cleft (NTD) interactions provides versatility to regulate synaptic transmission and plasticity
Suicide worldwide in 2019
More than 700 000 persons die by suicide every year globally. Suicide is the fourth leading cause of death among 15-29 year olds. The reduction of suicide rates in countries is an indicator in the UN SDGs, the WHO GPW13 and Mental Health Action Plan. Information material on data and statistics is necessary for advocacy and information purposes. This booklet provides this essential information in an accessible and digestible format. Target audiences are academics/researchers, development agencies, general public, health workers, journalists/media, nongovernmental organizations, policy-makers
A meta-analysis of the prevalence of Low Anterior Resection Syndrome and systematic review of risk factors
Aim: To summarize the reported prevalence and causative factors of Low Anterior Resection Syndrome (LARS) from studies using the LARS score.
Methods: A systematic literature search was conducted using Pubmed, Ovid Medline and the Cochrane database. Searches were performed using a combination of MeSH (medical subject headings) terms and key terms. Studies that were included used the LARS score as their primary collection tool. Studies were excluded if initial surgery was not for malignancy, or if the majority of LARS scores were from patients less than 1 year post initial surgery or closure of diverting stoma. Eligible studies were assessed with a validated quality assessment tool prior to performing a meta-analysis with quality effects model. Meta-analysis was conducted with prevalence estimates that had been transformed using the double arcsine method.
Results: Following the initial search and implementation of inclusion and exclusion criteria 11 studies were deemed suitable for meta-analysis. Meta-analysis found the estimated prevalence of major LARS was 41% (95% CI 34 -48). Where possible outlier studies were excluded, the prevalence was 42% (95%CI 35-48). Radiotherapy and tumour height were the most consistently assessed variables, both showing a consistent negative effect on bowel function. Defunctioning ileostomy was found to have a statically significant negative impact on bowel function in 4 of 11 studies. The majority of reported data has been produced by groups in Denmark and the United Kingdom with limited numbers provided by other locations. Available data is heterogenous with some variables having limited numbers, making meta-analysis of certain variables impossible.
Conclusions: There is significant prevalence of Low Anterior Resection Syndrome following oncological rectal resection. A low anastomotic height or history of radiotherapy are major risk factors
Oral health-related quality of life of patients rehabilitated with fixed and removable implant-supported dental prostheses.
Dental implants have become a mainstream treatment approach in daily practice, and because of their high survival rates over time, they have become the preferred treatment option for prosthetic rehabilitation in many situations. Despite the relatively high predictability of implant therapy and high costs to patients, patient perceptions of success and patient-reported outcome measures have become increasingly significant in implant dentistry. Increasing numbers of publications deal with oral health-related quality of life and/or patient-reported outcome measures. The aim of this paper was to provide an overview of the available evidence on oral health-related quality of life of fully and partially dentate patients rehabilitated with fixed and removable implant-supported dental prostheses. A comprehensive electronic search was performed on publications in English up to 2021. A selection of standardized questionnaires and scales used for the evaluation of oral health-related quality of life were analyzed and explained. The analysis encompassed three aspects: a functional evaluation of oral health-related quality of life, an esthetic assessment of oral health-related quality of life, and a cost-related evaluation of oral health-related quality of life for rehabilitation with dental implants. The data demonstrated that the preoperative expectations of patients markedly affected the outcomes perceived by the patients. As expected, reconstructions supported by implants substantially improved the stability of conventional dentures and allowed improved function and patient satisfaction. However, from a patient's perspective, oral health-related quality of life was not significantly greater for dental implants compared with conventional tooth-supported prostheses. The connection of the implants to the prostheses with locators or balls indicated high oral health-related quality of life. The data also suggest that patient expectation is not a good predictor of treatment outcome. In terms of esthetic outcomes, the data clearly indicate that patients' perceptions and clinicians' assessments differed, with those of clinicians yielding higher standards. There were no significant differences found between the esthetic oral health-related quality of life ratings for soft tissue-level implants compared with those for bone-level implants. Comparison of all-ceramic and metal-ceramic restorations showed no significant differences in patients' perceptions in terms of esthetic outcomes. Depending on the choice of outcome measure and financial marginal value, supporting a conventional removable partial denture with implants is cost-effective when the patient is willing to invest more to achieve a higher oral health-related quality of life. In conclusion, the oral health-related quality of life of patients rehabilitated with implant-supported dental prostheses did not show overall superiority over conventional prosthetics. Clinicians' and patients' evaluations, especially of esthetic outcomes, are, in the majority of cases, incongruent. Nevertheless, patient-reported outcomes are important in the evaluation of function, esthetics, and the cost-effectiveness of treatment with implant-supported dental prostheses, and should be taken into consideration in daily practice
GOODS-Herschel: Separating High Redshift active galactic Nuclei and star forming galaxies Using Infrared Color Diagnostics
We have compiled a large sample of 151 high redshift (z=0.5-4) galaxies
selected at 24 microns (S24>100 uJy) in the GOODS-N and ECDFS fields for which
we have deep Spitzer IRS spectroscopy, allowing us to decompose the
mid-infrared spectrum into contributions from star formation and activity in
the galactic nuclei. In addition, we have a wealth of photometric data from
Spitzer IRAC/MIPS and Herschel PACS/SPIRE. We explore how effective different
infrared color combinations are at separating our mid-IR spectroscopically
determined active galactic nuclei from our star forming galaxies. We look in
depth at existing IRAC color diagnostics, and we explore new color-color
diagnostics combining mid-IR, far-IR, and near-IR photometry, since these
combinations provide the most detail about the shape of a source's IR spectrum.
An added benefit of using a color that combines far-IR and mid-IR photometry is
that it is indicative of the power source driving the IR luminosity. For our
data set, the optimal color selections are S250/S24 vs. S8.0/S3.6 and S100/S24
vs. S8.0/S3.6; both diagnostics have ~10% contamination rate in the regions
occupied primarily by star forming galaxies and active galactic nuclei,
respectively. Based on the low contamination rate, these two new IR color-color
diagnostics are ideal for estimating both the mid-IR power source of a galaxy
when spectroscopy is unavailable and the dominant power source contributing to
the IR luminosity. In the absence of far-IR data, we present color diagnostics
using the WISE mid-IR bands which can efficiently select out high z (z~2) star
forming galaxies.Comment: Accepted for publication in ApJ. 13 pages, 8 figure
Diameter-Dependent Electron Mobility of InAs Nanowires
Temperature-dependent I-V and C-V spectroscopy of single InAs nanowire
field-effect transistors were utilized to directly shed light on the intrinsic
electron transport properties as a function of nanowire radius. From C-V
characterizations, the densities of thermally-activated fixed charges and trap
states on the surface of untreated (i.e., without any surface
functionalization) nanowires are investigated while enabling the accurate
measurement of the gate oxide capacitance; therefore, leading to the direct
assessment of the field-effect mobility for electrons. The field-effect
mobility is found to monotonically decrease as the radius is reduced to sub-10
nm, with the low temperature transport data clearly highlighting the drastic
impact of the surface roughness scattering on the mobility degradation for
miniaturized nanowires. More generally, the approach presented here may serve
as a versatile and powerful platform for in-depth characterization of
nanoscale, electronic materials
Synthesis, Contact Printing, and Device Characterization of Ni-Catalyzed, Crystalline InAs Nanowires
InAs nanowires have been actively explored as the channel material for high
performance transistors owing to their high electron mobility and ease of ohmic
metal contact formation. The catalytic growth of non-epitaxial InAs nanowires,
however, has often relied on the use of Au colloids which is non-CMOS
compatible. Here, we demonstrate the successful synthesis of high yield of
crystalline InAs nanowires with high yield and tunable diameters by using Ni
nanoparticles as the catalyst material on amorphous SiO2 substrates. The
nanowires show superb electrical properties with field-effect electron mobility
~2,700 cm2/Vs and ION/IOFF >103. The uniformity and purity of the grown InAs
nanowires are further demonstrated by large-scale assembly of parallel arrays
of nanowires on substrates via the contact printing process that enables high
performance, printable transistors, capable of delivering 5-10 mA ON currents
(~400 nanowires).Comment: 21 pages, 5 figures included, all in .docx format. Nano Research (In
Press
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