831 research outputs found
AI deployment on GBM diagnosis: a novel approach to analyze histopathological images using image feature-based analysis
Background: Glioblastoma (GBM) is one of the most common malignant primary brain tumors, which accounts for 60–70% of all gliomas. Conventional diagnosis and the decision of post-operation treatment plan for glioblastoma is mainly based on the feature-based qualitative analysis of hematoxylin and eosin-stained (H&E) histopathological slides by both an experienced medical technologist and a pathologist. The recent development of digital whole slide scanners makes AI-based histopathological image analysis feasible and helps to diagnose cancer by accurately counting cell types and/or quantitative analysis. However, the technology available for digital slide image analysis is still very limited. This study aimed to build an image feature-based computer model using histopathology whole slide images to differentiate patients with glioblastoma (GBM) from healthy control (HC). Method: Two independent cohorts of patients were used. The first cohort was composed of 262 GBM patients of the Cancer Genome Atlas Glioblastoma Multiform Collection (TCGA-GBM) dataset from the cancer imaging archive (TCIA) database. The second cohort was composed of 60 GBM patients collected from a local hospital. Also, a group of 60 participants with no known brain disease were collected. All the H&E slides were collected. Thirty-three image features (22 GLCM and 11 GLRLM) were retrieved from the tumor volume delineated by medical technologist on H&E slides. Five machine-learning algorithms including decision-tree (DT), extreme-boost (EB), support vector machine (SVM), random forest (RF), and linear model (LM) were used to build five models using the image features extracted from the first cohort of patients. Models built were deployed using the selected key image features for GBM diagnosis from the second cohort (local patients) as model testing, to identify and verify key image features for GBM diagnosis. Results: All five machine learning algorithms demonstrated excellent performance in GBM diagnosis and achieved an overall accuracy of 100% in the training and validation stage. A total of 12 GLCM and 3 GLRLM image features were identified and they showed a significant difference between the normal and the GBM image. However, only the SVM model maintained its excellent performance in the deployment of the models using the independent local cohort, with an accuracy of 93.5%, sensitivity of 86.95%, and specificity of 99.73%. Conclusion: In this study, we have identified 12 GLCM and 3 GLRLM image features which can aid the GBM diagnosis. Among the five models built, the SVM model proposed in this study demonstrated excellent accuracy with very good sensitivity and specificity. It could potentially be used for GBM diagnosis and future clinical application.</p
Surface Roughness and Effective Stick-Slip Motion
The effect of random surface roughness on hydrodynamics of viscous
incompressible liquid is discussed. Roughness-driven contributions to
hydrodynamic flows, energy dissipation, and friction force are calculated in a
wide range of parameters. When the hydrodynamic decay length (the viscous wave
penetration depth) is larger than the size of random surface inhomogeneities,
it is possible to replace a random rough surface by effective stick-slip
boundary conditions on a flat surface with two constants: the stick-slip length
and the renormalization of viscosity near the boundary. The stick-slip length
and the renormalization coefficient are expressed explicitly via the
correlation function of random surface inhomogeneities. The effective
stick-slip length is always negative signifying the effective slow-down of the
hydrodynamic flows by the rough surface (stick rather than slip motion). A
simple hydrodynamic model is presented as an illustration of these general
hydrodynamic results. The effective boundary parameters are analyzed
numerically for Gaussian, power-law and exponentially decaying correlators with
various indices. The maximum on the frequency dependence of the dissipation
allows one to extract the correlation radius (characteristic size) of the
surface inhomogeneities directly from, for example, experiments with torsional
quartz oscillators.Comment: RevTeX4, 14 pages, 3 figure
Association Between Raised Blood Pressure and Dysglycemia in Hong Kong Chinese
OBJECTIVE—To investigate the association between raised blood pressure and dysglycemia
Background-free detection of trapped ions
We demonstrate a Doppler cooling and detection scheme for ions with low-lying
D levels which almost entirely suppresses scattered laser light background,
while retaining a high fluorescence signal and efficient cooling. We cool a
single ion with a laser on the 2S1/2 to 2P1/2 transition as usual, but repump
via the 2P3/2 level. By filtering out light on the cooling transition and
detecting only the fluorescence from the 2P_3/2 to 2S1/2 decays, we suppress
the scattered laser light background count rate to 1 per second while
maintaining a signal of 29000 per second with moderate saturation of the
cooling transition. This scheme will be particularly useful for experiments
where ions are trapped in close proximity to surfaces, such as the trap
electrodes in microfabricated ion traps, which leads to high background scatter
from the cooling beam
Cultured circulating tumor cells and their derived xenografts for personalized oncology
AbstractRecent cancer research has demonstrated the existence of circulating tumor cells (CTCs) in cancer patient's blood. Once identified, CTC biomarkers will be invaluable tools for clinical diagnosis, prognosis and treatment. In this review, we propose ex vivo culture as a rational strategy for large scale amplification of the limited numbers of CTCs from a patient sample, to derive enough CTCs for accurate and reproducible characterization of the biophysical, biochemical, gene expressional and behavioral properties of the harvested cells. Because of tumor cell heterogeneity, it is important to amplify all the CTCs in a blood sample for a comprehensive understanding of their role in cancer metastasis. By analyzing critical steps and technical issues in ex vivo CTC culture, we developed a cost-effective and reproducible protocol directly culturing whole peripheral blood mononuclear cells, relying on an assumed survival advantage in CTCs and CTC-like cells over the normal cells to amplify this specified cluster of cancer cells
Danggui Buxue Tang – A Chinese herbal decoction activates the phosphorylations of extracellular signal-regulated kinase and estrogen receptor α in cultured MCF-7 cells
AbstractDanggui Buxue Tang (DBT), a Chinese herbal decoction used to treat ailments in women, contains Radix Astragali (Huangqi; RA) and Radix Angelicae Sinensis (Danggui; RAS). The weight ratio of RA to RAS used in DBT must be 5:1 as stipulated as early as AD 1247; however, DBT’s mechanism of action has never been described. Here, the estrogenic effects of DBT were investigated by determining the phosphorylations of estrogen receptor α (ERα) and extracellular signal-regulated kinase 1/2 (Erk1/2) in cultured MCF-7 cells. The application of DBT triggered the phosphorylation of ERα and Erk1/2 in a time-dependent manner. In contrast to the effect of estrogen, DBT triggered ERα phosphorylation at both S118 and S167. This DBT-specific phosphorylation was not triggered by an extract of one of the individual herbs, or by mixing the extracts of RA and RAS. DBT-induced downstream signals are described here. These signals suggest the uniqueness of this Chinese herbal decoction that requires a well-defined formulation
Cosmological parameters from SDSS and WMAP
We measure cosmological parameters using the three-dimensional power spectrum
P(k) from over 200,000 galaxies in the Sloan Digital Sky Survey (SDSS) in
combination with WMAP and other data. Our results are consistent with a
``vanilla'' flat adiabatic Lambda-CDM model without tilt (n=1), running tilt,
tensor modes or massive neutrinos. Adding SDSS information more than halves the
WMAP-only error bars on some parameters, tightening 1 sigma constraints on the
Hubble parameter from h~0.74+0.18-0.07 to h~0.70+0.04-0.03, on the matter
density from Omega_m~0.25+/-0.10 to Omega_m~0.30+/-0.04 (1 sigma) and on
neutrino masses from <11 eV to <0.6 eV (95%). SDSS helps even more when
dropping prior assumptions about curvature, neutrinos, tensor modes and the
equation of state. Our results are in substantial agreement with the joint
analysis of WMAP and the 2dF Galaxy Redshift Survey, which is an impressive
consistency check with independent redshift survey data and analysis
techniques. In this paper, we place particular emphasis on clarifying the
physical origin of the constraints, i.e., what we do and do not know when using
different data sets and prior assumptions. For instance, dropping the
assumption that space is perfectly flat, the WMAP-only constraint on the
measured age of the Universe tightens from t0~16.3+2.3-1.8 Gyr to
t0~14.1+1.0-0.9 Gyr by adding SDSS and SN Ia data. Including tensors, running
tilt, neutrino mass and equation of state in the list of free parameters, many
constraints are still quite weak, but future cosmological measurements from
SDSS and other sources should allow these to be substantially tightened.Comment: Minor revisions to match accepted PRD version. SDSS data and ppt
figures available at http://www.hep.upenn.edu/~max/sdsspars.htm
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
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