517 research outputs found
Leptonic contribution to the bulk viscosity of nuclear matter
For beta-equilibrated nuclear matter we estimate the contribution to the bulk
viscosity from purely leptonic processes, namely the conversion of electrons to
and from muons. For oscillation frequencies in the kiloHertz range, we find
that this process provides the dominant contribution to the bulk viscosity when
the temperature is well below the critical temperature for superconductivity or
superfluidity of the nuclear matter.Comment: 15 pages, LaTeX, new appendix and general clarifications in response
to referee comment
Tests of the Equivalence Principle with Neutral Kaons
We test the Principle of Equivalence for particles and antiparticles, using
CPLEAR data on tagged K0 and K0bar decays into pi^+ pi^-. For the first time,
we search for possible annual, monthly and diurnal modulations of the
observables |eta_{+-}| and phi_{+-}, that could be correlated with variations
in astrophysical potentials. Within the accuracy of CPLEAR, the measured values
of |eta_{+-}| and phi_{+-} are found not to be correlated with changes of the
gravitational potential. We analyze data assuming effective scalar, vector and
tensor interactions, and we conclude that the Principle of Equivalence between
particles and antiparticles holds to a level of 6.5, 4.3 and 1.8 x 10^{-9},
respectively, for scalar, vector and tensor potentials originating from the Sun
with a range much greater than the distance Earth-Sun. We also study
energy-dependent effects that might arise from vector or tensor interactions.
Finally, we compile upper limits on the gravitational coupling difference
between K0 and K0bar as a function of the scalar, vector and tensor interaction
range.Comment: 15 pages latex 2e, five figures, one style file (cernart.csl)
incorporate
Profiles and outcome of traditional healing practices for severe mental illnesses in two districts of Eastern Uganda
Background : The WHO estimates that more than 80% of African populations attend traditional healers for health reasons and that 40%–60% of these have some kind of mental illness. However, little is known about the profiles and outcome of this traditional approach to treatment. Objective : The purpose of this study was to describe the profiles and outcome of traditional healing practices for severe mental illnesses in Jinja and Iganga districts in the Busoga region of Eastern Uganda. Methods : Four studies were conducted. Study I used focus group discussions (FGDs) with case vignettes with local community members and traditional healers to explore the lay concepts of psychosis. Studies II and III concerned a cross-sectional survey of patients above 18 years at the traditional healer's shrines and study IV was made on a prospective cohort of patients diagnosed with psychosis in study III. Manual content analysis was used in study I; quantitative data in studies II, III, and IV were analyzed at univariate, bivariate, and multivariate levels to determine the association between psychological distress and socio-demographic factors; for study IV, factors associated with outcome were analyzed. One-way ANOVA for independent samples was the analysis used in Study IV. Results : The community gave indigenous names to psychoses (mania, schizophrenia, and psychotic depression) and had multiple explanatory models for them. Thus multiple solutions for these problems were sought. Of the 387 respondents, the prevalence of psychological distress was 65.1%, where 60.2% had diagnosable current mental illness, and 16.3% had had one disorder in their lifetime. Over 80% of patients with psychosis used both biomedical and traditional healing systems. Those who combined these two systems seemed to have a better outcome. All the symptom scales showed a percentage reduction of more than 20% at the 3- and 6-month follow-ups. Conclusion : Traditional healers shoulder a large burden of care of patients with mental health problems. This calls for all those who share the goal of improving the mental health of individuals to engage with traditional healers
PDK-1/AKT pathway as a novel therapeutic target in rhabdomyosarcoma cells using OSU-03012 compound
Rhabdomyosarcoma (RMS) is the most common paediatric soft-tissue sarcoma including two major subtypes, alveolar rhabdomyosarcoma (ARMS) and embryonal rhabdomyosarcoma (ERMS). Increasing evidence suggests that oncogenesis of RMS involves multistages of signalling protein dysregulation which may include prolonged activation of serine/threonine kinases such as phosphoinositide-dependant kinase-1 (PDK-1) and AKT. To date, whether PDK-1/AKT pathway is activated in RMS is unknown. This study was to examine phosphorylation status of AKT and to evaluate a novel small molecular inhibitor, OSU-03012 targeting PDK-1 in RMS. We examined phosphorylation levels of AKT using ARMS and ERMS tissue microarray and immunohistochemistry staining. Our results showed phospho-AKTThr308 level is elevated 42 and 35% in ARMS and ERMS, respectively. Phospho-AKTSer473 level is also increased 43% in ARMS and 55% in ERMS. Furthermore, we showed that OSU-03012 inhibits cell viability and induces apoptosis in ARMS and ERMS cell lines (RH30, SMS-CTR), which express elevated phospho-AKT levels. Normal cells are much less sensitive to OSU-03012 and in which no detectable apoptosis was observed. This study showed, for the first time, that PDK-1/AKT pathway is activated in RMS and may play an important role in survival of RMS. PDK-1/AKT pathway may be an attractive therapeutic target for cancer intervention in RMS using OSU-03012
Morphological brain differences between adult stutterers and non-stutterers
BACKGROUND: The neurophysiological and neuroanatomical foundations of persistent developmental stuttering (PDS) are still a matter of dispute. A main argument is that stutterers show atypical anatomical asymmetries of speech-relevant brain areas, which possibly affect speech fluency. The major aim of this study was to determine whether adults with PDS have anomalous anatomy in cortical speech-language areas. METHODS: Adults with PDS (n = 10) and controls (n = 10) matched for age, sex, hand preference, and education were studied using high-resolution MRI scans. Using a new variant of the voxel-based morphometry technique (augmented VBM) the brains of stutterers and non-stutterers were compared with respect to white matter (WM) and grey matter (GM) differences. RESULTS: We found increased WM volumes in a right-hemispheric network comprising the superior temporal gyrus (including the planum temporale), the inferior frontal gyrus (including the pars triangularis), the precentral gyrus in the vicinity of the face and mouth representation, and the anterior middle frontal gyrus. In addition, we detected a leftward WM asymmetry in the auditory cortex in non-stutterers, while stutterers showed symmetric WM volumes. CONCLUSIONS: These results provide strong evidence that adults with PDS have anomalous anatomy not only in perisylvian speech and language areas but also in prefrontal and sensorimotor areas. Whether this atypical asymmetry of WM is the cause or the consequence of stuttering is still an unanswered question
Homosexual Women Have Less Grey Matter in Perirhinal Cortex than Heterosexual Women
Is sexual orientation associated with structural differences in the brain? To address this question, 80 homosexual and heterosexual men and women (16 homosexual men and 15 homosexual women) underwent structural MRI. We used voxel-based morphometry to test for differences in grey matter concentration associated with gender and sexual orientation. Compared with heterosexual women, homosexual women displayed less grey matter bilaterally in the temporo-basal cortex, ventral cerebellum, and left ventral premotor cortex. The relative decrease in grey matter was most prominent in the left perirhinal cortex. The left perirhinal area also showed less grey matter in heterosexual men than in heterosexual women. Thus, in homosexual women, the perirhinal cortex grey matter displayed a more male-like structural pattern. This is in accordance with previous research that revealed signs of sex-atypical prenatal androgenization in homosexual women, but not in homosexual men. The relevance of the perirhinal area for high order multimodal (olfactory and visual) object, social, and sexual processing is discussed
Sprouty Proteins Inhibit Receptor-mediated Activation of Phosphatidylinositol-specific Phospholipase C
PLCγ03B3 binds Spry1 and Spry2. Overexpression of Spry decreased PLCγ03B3 activity and IP3 and DAG production, whereas Spry-deficient cells yielded more IP3. Spry overexpression inhibited T-cell receptor signaling and Spry1 null T-cells hyperproliferated with TCR ligation. Through action of PLCγ03B3, Spry may influence signaling through multiple receptors
Surface Properties of Helicobacter pylori Urease Complex Are Essential for Persistence
The enzymatic activity of Helicobacter pylori's urease neutralises stomach acidity, thereby promoting infection by this pathogen. Urease protein has also been found to interact with host cells in vitro, although this property's possible functional importance has not been studied in vivo. To test for a role of the urease surface in the host/pathogen interaction, surface exposed loops that display high thermal mobility were targeted for inframe insertion mutagenesis. H. pylori expressing urease with insertions at four of eight sites tested retained urease activity, which in three cases was at least as stable as was wild-type urease at pH 3. Bacteria expressing one of these four mutant ureases, however, failed to colonise mice for even two weeks, and a second had reduced bacterial titres after longer term (3 to 6 months) colonisation. These results indicate that a discrete surface of the urease complex is important for H. pylori persistence during gastric colonisation. We propose that this surface interacts directly with host components important for the host-pathogen interaction, immune modulation or other actions that underlie H. pylori persistence in its special gastric mucosal niche
Copernicus Marine Service Ocean State Report
This is the final version. Available from Taylor & Francis via the DOI in this record
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