89 research outputs found
Black hole solutions with dilatonic hair in higher curvature gravity
A new numerical integration method for examining a black hole structure was
realized. Black hole solutions with dilatonic hair of 4D low energy effective
SuperString Theory action with Gauss-Bonnet quadratic curvature contribution
were studied, using this method, inside and outside the event horizon.
Thermodynamical properties of this solution were also studied.Comment: 10 pages, 6 figures, RevTeX, figures in LaTeX or PostScript are
avaible upon request via e-mail address: [email protected], Submitted
to Phys.Rev.
Recommended from our members
Identification of RPS14 as a 5q- syndrome gene by RNA interference screen
Somatic chromosomal deletions in cancer are thought to indicate the location of tumor suppressor genes, whereby complete loss of gene function occurs through biallelic deletion, point mutation, or epigenetic silencing, thus fulfilling Knudson's two-hit hypothesis.1 In many recurrent deletions, however, such biallelic inactivation has not been found. One prominent example is the 5q- syndrome, a subtype of myelodysplastic syndrome (MDS) characterized by a defect in erythroid differentiation.2 Here, we describe an RNA interference (RNAi)-based approach to discovery of the 5q- disease gene. We find that partial loss of function of the ribosomal protein RPS14 phenocopies the disease in normal hematopoietic progenitor cells, and moreover that forced expression of RPS14 rescues the disease phenotype in patient-derived bone marrow cells. In addition, we identified a block in the processing of pre-rRNA in RPS14 deficient cells that is highly analogous to the functional defect in Diamond Blackfan Anemia, linking the molecular pathophysiology of the 5q- syndrome to a congenital bone marrow failure syndrome. These results indicate that the 5q- syndrome is caused by a defect in ribosomal protein function, and suggests that RNAi screening is an effective strategy for identifying causal haploinsufficiency disease genes
Strong-weak CP hierarchy from non-renormalization theorems
We point out that the hierarchy between the measured values of the CKM phase
and the strong CP phase has a natural origin in supersymmetry with spontaneous
CP violation and low energy supersymmetry breaking. The underlying reason is
simple and elegant: in supersymmetry the strong CP phase is protected by an
exact non-renormalization theorem while the CKM phase is not. We present
explicit examples of models which exploit this fact and discuss corrections to
the non-renormalization theorem in the presence of supersymmetry breaking. This
framework for solving the strong CP problem has generic predictions for the
superpartner spectrum, for CP and flavor violation, and predicts a preferred
range of values for electric dipole moments.Comment: 36 pages, 3 figure
Enhanced contribution to quark and neutron electric dipole moments with small mixing of right-handed currents and CKM CP violation
We study the light quark and the neutron electric dipole moments (EDMs) under
the assumptions that the CP source is still in the usual CKM matrix and that
there is a small mixing of right-handed charged currents in the quark sector.
We find that the EDMs arise already at two loop order that are much larger than
the standard model (SM) result even for a small mixing.Comment: 9 pages, revtex, axodraw.sty, 1 figure, published version in Phys.
Rev. D. References updated, minor corrections and typos fixe
A call for transparent reporting to optimize the predictive value of preclinical research
The US National Institute of Neurological Disorders and Stroke convened major stakeholders in June 2012 to discuss how to improve the methodological reporting of animal studies in grant applications and publications. The main workshop recommendation is that at a minimum studies should report on sample-size estimation, whether and how animals were randomized, whether investigators were blind to the treatment, and the handling of data. We recognize that achieving a meaningful improvement in the quality of reporting will require a concerted effort by investigators, reviewers, funding agencies and journal editors. Requiring better reporting of animal studies will raise awareness of the importance of rigorous study design to accelerate scientific progress
Early predictors of impaired social functioning in male rhesus macaques (Macaca mulatta)
Autism spectrum disorder (ASD) is characterized by social cognition impairments but its basic disease mechanisms remain poorly understood. Progress has been impeded by the absence of animal models that manifest behavioral phenotypes relevant to ASD. Rhesus monkeys are an ideal model organism to address this barrier to progress. Like humans, rhesus monkeys are highly social, possess complex social cognition abilities, and exhibit pronounced individual differences in social functioning. Moreover, we have previously shown that Low-Social (LS) vs. High-Social (HS) adult male monkeys exhibit lower social motivation and poorer social skills. It is not known, however, when these social deficits first emerge. The goals of this study were to test whether juvenile LS and HS monkeys differed as infants in their ability to process social information, and whether infant social abilities predicted later social classification (i.e., LS vs. HS), in order to facilitate earlier identification of monkeys at risk for poor social outcomes. Social classification was determined for N = 25 LS and N = 25 HS male monkeys that were 1–4 years of age. As part of a colony-wide assessment, these monkeys had previously undergone, as infants, tests of face recognition memory and the ability to respond appropriately to conspecific social signals. Monkeys later identified as LS vs. HS showed impairments in recognizing familiar vs. novel faces and in the species-typical adaptive ability to gaze avert to scenes of conspecific aggression. Additionally, multivariate logistic regression using infant social ability measures perfectly predicted later social classification of all N = 50 monkeys. These findings suggest that an early capacity to process important social information may account for differences in rhesus monkeys’ motivation and competence to establish and maintain social relationships later in life. Further development of this model will facilitate identification of novel biological targets for intervention to improve social outcomes in at-risk young monkeys
Cancer Genome Sequencing and Its Implications for Personalized Cancer Vaccines
New DNA sequencing platforms have revolutionized human genome sequencing. The dramatic advances in genome sequencing technologies predict that the $1,000 genome will become a reality within the next few years. Applied to cancer, the availability of cancer genome sequences permits real-time decision-making with the potential to affect diagnosis, prognosis, and treatment, and has opened the door towards personalized medicine. A promising strategy is the identification of mutated tumor antigens, and the design of personalized cancer vaccines. Supporting this notion are preliminary analyses of the epitope landscape in breast cancer suggesting that individual tumors express significant numbers of novel antigens to the immune system that can be specifically targeted through cancer vaccines
QCD and strongly coupled gauge theories : challenges and perspectives
We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe
Neutron Electric Dipole Moment In The Standard Model: Valence Quark Contributions
We present a complete three-loop calculation of the electric dipole moment of
the and quarks in the Standard Model. For the quark, more relevant
for the experimentally important neutron electric dipole moment, we find
cancellations which lead to an order of magnitude suppression compared with
previous estimates.Comment: 8 pages, revte
Gene expression profiles derived from fine needle aspiration correlate with response to systemic chemotherapy in breast cancer
BACKGROUND: Drug resistance in breast cancer is a major obstacle to successful chemotherapy. In this study we used cDNA microarray technology to examine gene expression profiles obtained from fine needle aspiration (FNA) of primary breast tumors before and after systemic chemotherapy. Our goal was to determine the feasibility of obtaining representative expression array profiles from limited amounts of tissue and to identify those expression profiles that correlate with treatment response. METHODS: Repeat presurgical FNA samples were taken from six patients who were to undergo primary surgical treatment. Additionally, a group of 10 patients who were to receive neoadjuvant chemotherapy underwent two FNAs before chemotherapy (adriamycin 60 mg/m(2) and cyclophosphamide 600 mg/m(2)) followed by another FNA on day 21 after the first cycle. Total RNA was amplified with T7 Eberwine's procedure and labeled cDNA was hybridized onto a 7600-feature glass cDNA microarray. RESULTS: We identified candidate gene expression profiles that might distinguish tumors with complete response to chemotherapy from tumors that do not respond, and found that the number of genes that change after one cycle of chemotherapy was 10 times greater in the responding group than in the non-responding group. CONCLUSION: This study supports the suitability of FNA-derived cDNA microarray expression profiling of breast cancers as a comprehensive genomic approach for studying the mechanisms of drug resistance. Our findings also demonstrate the potential of monitoring post-chemotherapy changes in expression profiles as a measure of pharmacodynamic effect and suggests that these approaches might yield useful results when validated by larger studies
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