595 research outputs found
Lepton flavor violating signals of the neutral top-pion in future lepton colliders
The presence of the top-pions in the low-energy spectrum is
an inevitable feature of the topcolor scenario. Taking into account the
constraints of the present experimental limit of the lepton flavor
violating() process on the free parameters of
topcolor-assisted techicolor(TC2) models, we study the contributions of the
neutral top-pion to the processes (or ), (or ), , and via the
flavor changing () couplings and discuss the
possibility of searching for the signals via these processes in future
lepton colliders.Comment: References added, some typos corrected. Version to be published in
Phys. Rev.
River network routing on the NHDPlus dataset
International audienceThe mapped rivers and streams of the contiguous United States are available in a geographic information system (GIS) dataset called National Hydrography Dataset Plus (NHDPlus). This hydrographic dataset has about 3 million river and water body reaches along with information on how they are connected into net- works. The U.S. Geological Survey (USGS) National Water Information System (NWIS) provides stream- flow observations at about 20 thousand gauges located on theNHDPlus river network.Ariver networkmodel called Routing Application for Parallel Computation of Discharge (RAPID) is developed for the NHDPlus river network whose lateral inflow to the river network is calculated by a land surface model. A matrix-based version of the Muskingum method is developed herein, which RAPID uses to calculate flow and volume of water in all reaches of a river network with many thousands of reaches, including at ungauged locations. Gauges situated across river basins (not only at basin outlets) are used to automatically optimize the Muskingum parameters and to assess river flow computations, hence allowing the diagnosis of runoff com- putations provided by land surfacemodels.RAPIDis applied to theGuadalupe and SanAntonioRiver basins in Texas, where flow wave celerities are estimated at multiple locations using 15-min data and can be reproduced reasonably with RAPID. This river model can be adapted for parallel computing and although the matrix method initially adds a large overhead, river flow results can be obtained faster than with the traditionalMuskingummethod when using a few processing cores, as demonstrated in a synthetic study using the upper Mississippi River basin
Quantifying Parameter Sensitivity, Interaction and Transferability in Hydrologically Enhanced Versions of Noah-LSM over Transition Zones
We use sensitivity analysis to identify the parameters that are most responsible for shaping land surface model (LSM) simulations and to understand the complex interactions in three versions of the Noah LSM: the standard version (STD), a version enhanced with a simple groundwater module (GW), and version augmented by a dynamic phenology module (DV). We use warm season, high-frequency, near-surface states and turbulent fluxes collected over nine sites in the US Southern Great Plains. We quantify changes in the pattern of sensitive parameters, the amount and nature of the interaction between parameters, and the covariance structure of the distribution of behavioral parameter sets. Using Sobol s total and first-order sensitivity indexes, we show that very few parameters directly control the variance of the model output. Significant parameter interaction occurs so that not only the optimal parameter values differ between models, but the relationships between parameters change. GW decreases parameter interaction and appears to improve model realism, especially at wetter sites. DV increases parameter interaction and decreases identifiability, implying it is overparameterized and/or underconstrained. A case study at a wet site shows GW has two functional modes: one that mimics STD and a second in which GW improves model function by decoupling direct evaporation and baseflow. Unsupervised classification of the posterior distributions of behavioral parameter sets cannot group similar sites based solely on soil or vegetation type, helping to explain why transferability between sites and models is not straightforward. This evidence suggests a priori assignment of parameters should also consider climatic differences
Diagnostic value of cell-free DNA to biliary tract cancers: a meta-analysis
Objective·To comprehensively evaluate the diagnostic accuracy of cell-free DNA (cfDNA) to biliary tract cancer (BTC), and provide a basis for better clinical application.Methods·Clinical studies on the diagnostic value of cfDNA to BTC were collected by searching eight databases from inception to April 2023. The studies were selected according to the inclusion and exclusion criteria, and then data was extracted. The threshold effects were assessed with Spearman′s rank correlation analysis, and heterogeneity among the included studies was analyzed by using Cochran′s Q test and I2 test. A bivariate mixed-effects model was fitted, and statistics such as overall sensitivity, specificity, and area under the curve (AUC) were calculated to determine the diagnostic performance. The subgroup analyses were carried out based on the study type, sample size, detection method, sample source, and diagnostic reference standard.Results·A total of 28 diagnosis tests were included, all of which were evaluated as medium-high quality by using Diagnostic Accuracy Studies Tool Version 2 (QUADAS-2). The presence of threshold effects was found by using the Spearman rank correlation analysis. The pooled sensitivity was 0.80 (95%CI 0.67‒0.88), and specificity was 0.96 (95%CI 0.92‒0.98), positive likelihood ratio (PLR) was 22.7 (95%CI 9.4‒55.2), negative likelihood ratio (NLR) was 0.21 (95%CI 0.12‒0.36), and diagnostic odds ratio (DOR) was 108 (95%CI 31‒374), respectively. The AUC of the summary receiver operating characteristic (SROC) curve was 0.96 (95%CI 0.94‒0.98), demonstrating the high accuracy of cfDNA in the diagnosis of BTC. The results of subgroup analyses suggested that the accuracy and sensitivity of choosing different testing methods and sample sources varied.Conclusion·The detection of cfDNA has high sensitivity and specificity in diagnosing BTC, and is suitable for the patients suspected to be malignant after screening with imaging tests and conventional tumor markers. However, the standardization and uniformity of detection methods and sample sources still need to be further standardized by conducting clinical studies on a wider population
2017-2018 Master Class - Elmar Oliveira (Violin)
https://spiral.lynn.edu/conservatory_masterclasses/1152/thumbnail.jp
Progress and outlook on advanced fly scans based on Mamba
Development related to PandABox-based fly scans is an important part of the
active work on Mamba, the software framework for beamline experiments at the
High Energy Photon Source (HEPS); presented in this paper is the progress of
our development, and some outlook for advanced fly scans based on knowledge
learned during the process. By treating fly scans as a collaboration between a
few loosely coupled subsystems - motors / mechanics, detectors / data
processing, sequencer devices like PandABox - systematic analyses of issues in
fly scans are conducted. Interesting products of these analyses include a
general-purpose software-based fly-scan mechanism, a general way to design
undulator-monochromator fly scans, a sketch of how to practically implement
online tuning of fly-scan behaviours based on processing of the data acquired,
and many more. Based on the results above, an architectural discussion on
>=10kHz fly scans is given.Comment: 10 pages, 6 figures, accepted by Synchrotron Rad. New
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Alterations of Serum Levels of BDNF-Related miRNAs in Patients with Depression
Depression is a serious and potentially life-threatening mental disorder with unknown etiology. Emerging evidence shows that brain-derived neurotrophic factor (BDNF) and microRNAs (miRNAs) play critical roles in the etiology of depression. Here this study was aimed to identify and characterize the roles of BDNF and its putative regulatory miRNAs in depression. First, we identified that miR-182 may be a putative miRNA that regulates BDNF levels by bioinformatic studies, and characterized the effects of miR-182 on the BDNF levels using cell-based studies, side by side with miR-132 (a known miRNA that regulates BDNF expression). We showed that treatment of miR-132 and miR-182 respectively decreased the BDNF protein levels in a human neuronal cell model, supporting the regulatory roles of miR-132 and miR-182 on the BDNF expression. Furthermore, we explored the roles of miR-132 and miR-182 on the BDNF levels in depression using human subjects by assessing their serum levels. Compared with the healthy controls, patients with depression showed lower serum BDNF levels (via the enzyme-linked immunosorbent assays) and higher serum miR-132 and miR-182 levels (via the real-time PCR). Finally, the Pearson’s (or Spearman’s) correlation coefficient was calculated to study whether there was a relationship among the Self-Rating Depression Scale score, the serum BDNF levels, and serum BDNF-related miRNA levels. Our results revealed that there was a significant negative correlation between the SDS scores and the serum BDNF levels, and a positive correlation between the SDS scores and miR-132 levels. In addition, we found a reverse relationship between the serum BDNF levels and the miR-132/miR-182 levels in depression. Collectively, we provided evidence supporting that miR-182 is a putative BDNF-regulatory miRNA, and suggested that the serum BDNF and its related miRNAs may be utilized as important biomarkers in the diagnosis or as therapeutic targets of depression
Santacruzamate A Ameliorates AD-Like Pathology by Enhancing ER Stress Tolerance Through Regulating the Functions of KDELR and Mia40-ALR in vivo and in vitro
Aggregated amyloid-β protein (Aβ) and Aβ-induced neuronal apoptosis have been implicated as critical factors in the pathophysiology of Alzheimer’s disease (AD). Certain preclinical results have indicated that the increased accumulation of protein aggregates in AD-affected neurons activates the unfolded protein response (UPR), a pathological phenomenon, which predominantly mediates the aberrant endoplasmic reticulum (ER) stress and apoptotic cascades in neuronal cells. In the present study, we confirmed that Santacruzamate A (STA, a natural product isolated from a Panamanian marine cyanobacterium) attenuates Aβ protein fragment 25–35 (Aβ25–35)-induced toxicity in PC12 cells and rescues cognitive deficits in APPswe/PS1dE9 mice by enhancing ER stress tolerance. We first demonstrated the anti-apoptotic effects of STA by evaluating caspase-3 activity, annexin V/propidium iodide (PI) staining, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Behavioral testing of STA-treated APPswe/PS1dE9 mice showed that the pronounced memory impairments were ameliorated and that the consolidated memories were stably maintained over a 2-week period. The mechanistic studies provided evidence that STA inhibited Aβ25–35-induced UPR and ER stress by regulating the ER retention signal (KDEL) receptor, which reinforced the retention of resident chaperones in the ER lumen. Furthermore, STA regulated the expression of the mitochondrial intermembrane space assembly protein 40 (Mia40) and augmenter of liver regeneration (ALR), which ultimately attenuated the mitochondrial fission and apoptosis pathways. Together, our present findings suggest that the KDEL receptor and Mia40-ALR play a role in mitigating Aβ25–35-induced neurotoxicity, which might in turn positively regulate learning and memory. These observations support that STA may be a promising agent for reversing the progression of AD
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