1,423 research outputs found
Late-time Phase transition and the Galactic halo as a Bose Liquid: (II) the Effect of Visible Matter
In the previous work, we investigated the rotation curves of galaxies
assuming that the dark matter consists of ultra light boson appearing in
late time phase transition' theory. Generalizing this work, we consider the
effect of visible matter and classify the types of rotation curves as we vary
the fraction of the mass and extention of visible matter. We show that visible
matter, in galaxies with flat rotation curves, has mass fraction and it is confined within the distance fraction .Comment: 10 pages, 10 figures included, to appear in Phys. Rev. D50,p365
Precise predictions for W \gamma \gamma +jet production at hadron colliders
In this letter we report on a calculation of W gamma gamma + jet production
at next-to-leading order QCD. We include the leptonic decays of the W and take
into account all off-shell and finite width effects. This is the first
computation which falls into the category of triboson+jet production at
next-to-leading order QCD. In total we find sizable corrections with nontrivial
phase space dependencies. Therefore, our results are important for
phenomenological analyses such as the extraction of anomalous electroweak
quartic couplings from inclusive hadron collider data.Comment: 6 pages, 6 figure
Differential expression of miRNAs in colon cancer between African and Caucasian Americans: Implications for cancer racial health disparities
Colorectal cancer (CRC) incidence and mortality are higher in African Americans (AAs) than in Caucasian Americans (CAs) and microRNAs (miRNAs) have been found to be dysregulated in colonic and other neoplasias. The aim of this exploratory study was to identify candidate miRNAs that could contribute to potential biological differences between AA and CA colon cancers. Total RNA was isolated from tumor and paired adjacent normal colon tissue from 30 AA and 31 CA colon cancer patients archived at Stony Brook University (SBU) and Washington University (WU)-St. Louis Medical Center. miRNA profiles were determined by probing human genome-wide miRNA arrays with RNA isolated from each sample. Using repeated measures analysis of variance (RANOVA), miRNAs were selected that exhibited significant (p<0.05) interactions between race and tumor or significant (fold change >1.5, p<0.05) main effects of race and/or tumor. Quantitative polymerase chain reaction (q-PCR) was used to confirm miRNAs identified by microarray analysis. Candidate miRNA targets were analyzed using immunohistochemistry. RANOVA results indicated that miR-182, miR152, miR-204, miR-222 and miR-202 exhibited significant race and tumor main effects. Of these miRNAs, q-PCR analysis confirmed that miR-182 was upregulated in AA vs. CA tumors and exhibited significant race:tumor interaction. Immunohistochemical analysis revealed that the levels of FOXO1 and FOXO3A, two potential miR-182 targets, are reduced in AA tumors. miRNAs may play a role in the differences between AA and CA colon cancer. Specifically, differences in miRNA expression levels of miR-182 may contribute to decreased survival in AA colon cancer patients
Validation of a contemporary prostate cancer grading system using prostate cancer death as outcome
BACKGROUND: Gleason scoring (GS) has major deficiencies and a novel system of five grade groups (GS⩽6; 3+4; 4+3; 8; ⩾9) has been recently agreed and included in the WHO 2016 classification. Although verified in radical prostatectomies using PSA relapse for outcome, it has not been validated using prostate cancer death as an outcome in biopsy series. There is debate whether an ‘overall' or ‘worst' GS in biopsies series should be used. METHODS: Nine hundred and eighty-eight prostate cancer biopsy cases were identified between 1990 and 2003, and treated conservatively. Diagnosis and grade was assigned to each core as well as an overall grade. Follow-up for prostate cancer death was until 31 December 2012. A log-rank test assessed univariable differences between the five grade groups based on overall and worst grade seen, and using univariable and multivariable Cox proportional hazards. Regression was used to quantify differences in outcome. RESULTS: Using both ‘worst' and ‘overall' GS yielded highly significant results on univariate and multivariate analysis with overall GS slightly but insignificantly outperforming worst GS. There was a strong correlation with the five grade groups and prostate cancer death. CONCLUSIONS: This is the largest conservatively treated prostate cancer cohort with long-term follow-up and contemporary assessment of grade. It validates the formation of five grade groups and suggests that the ‘worst' grade is a valid prognostic measure
The NMDA agonist D-cycloserine facilitates fear memory consolidation in humans
Animal research suggests that the consolidation of fear and
extinction memories depends on N-methyl D-aspartate (NMDA)-
type glutamate receptors. Using a fear conditioning and extinction
paradigm in healthy normal volunteers, we show that postlearning
administration of the NMDA partial agonist D-cycloserine (DCS)
facilitates fear memory consolidation, evidenced behaviorally by
enhanced skin conductance responses, relative to placebo, for
presentations of a conditioned stimulus (CS) at a memory test
performed 72 h later. DCS also enhanced CS-evoked neural
responses in a posterior hippocampus/collateral sulcus region and
in the medial prefrontal cortex at test. Our data suggest a role for
NMDA receptors in regulating fear memory consolidation in humans
Multiscale approach including microfibril scale to assess elastic constants of cortical bone based on neural network computation and homogenization method
The complexity and heterogeneity of bone tissue require a multiscale
modelling to understand its mechanical behaviour and its remodelling
mechanisms. In this paper, a novel multiscale hierarchical approach including
microfibril scale based on hybrid neural network computation and homogenisation
equations was developed to link nanoscopic and macroscopic scales to estimate
the elastic properties of human cortical bone. The multiscale model is divided
into three main phases: (i) in step 0, the elastic constants of collagen-water
and mineral-water composites are calculated by averaging the upper and lower
Hill bounds; (ii) in step 1, the elastic properties of the collagen microfibril
are computed using a trained neural network simulation. Finite element (FE)
calculation is performed at nanoscopic levels to provide a database to train an
in-house neural network program; (iii) in steps 2 to 10 from fibril to
continuum cortical bone tissue, homogenisation equations are used to perform
the computation at the higher scales. The neural network outputs (elastic
properties of the microfibril) are used as inputs for the homogenisation
computation to determine the properties of mineralised collagen fibril. The
mechanical and geometrical properties of bone constituents (mineral, collagen
and cross-links) as well as the porosity were taken in consideration. This
paper aims to predict analytically the effective elastic constants of cortical
bone by modelling its elastic response at these different scales, ranging from
the nanostructural to mesostructural levels. Our findings of the lowest scale's
output were well integrated with the other higher levels and serve as inputs
for the next higher scale modelling. Good agreement was obtained between our
predicted results and literature data.Comment: 2
Combined Hepatic and Splenic Abscesses in a Patient with Ulcerative Colitis
Liver abscesses are very rare complications of ulcerative colitis, and furthermore, there has been only one case of splenic abscess in a patient with ulcerative colitis reported in the English literature. We recently encountered a patient with ulcerative colitis accompanied by both hepatic and splenic abscesses. The patient was treated with abscess drainage as well as sulfasalazine and antibiotics. Follow-up sonography of the abdomen showed complete resolution of the lesions. To our knowledge, this is the first report of combined case of multiple liver abscesses combined with splenic abscess in a patient with ulcerative colitis
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