Quasi-Normal Modes of Stars and Black Holes

Perturbations of stars and black holes have been one of the main topics of relativistic astrophysics for the last few decades. They are of particular importance today, because of their relevance to gravitational wave astronomy. In this review we present the theory of quasi-normal modes of compact objects from both the mathematical and astrophysical points of view. The discussion includes perturbations of black holes (Schwarzschild, Reissner-Nordstr\"om, Kerr and Kerr-Newman) and relativistic stars (non-rotating and slowly-rotating). The properties of the various families of quasi-normal modes are described, and numerical techniques for calculating quasi-normal modes reviewed. The successes, as well as the limits, of perturbation theory are presented, and its role in the emerging era of numerical relativity and supercomputers is discussed.Comment: 74 pages, 7 figures, Review article for "Living Reviews in Relativity

Estrogen regulation of apoptosis: how can one hormone stimulate and inhibit?

The link between estrogen and the development and proliferation of breast cancer is well documented. Estrogen stimulates growth and inhibits apoptosis through estrogen receptor-mediated mechanisms in many cell types. Interestingly, there is strong evidence that estrogen induces apoptosis in breast cancer and other cell types. Forty years ago, before the development of tamoxifen, high-dose estrogen was used to induce tumor regression of hormone-dependent breast cancer in post-menopausal women. While the mechanisms by which estrogen induces apoptosis were not completely known, recent evidence from our laboratory and others demonstrates the involvement of the extrinsic (Fas/FasL) and the intrinsic (mitochondria) pathways in this process. We discuss the different apoptotic signaling pathways involved in E2 (17β-estradiol)-induced apoptosis, including the intrinsic and extrinsic apoptosis pathways, the NF-κB (nuclear factor-kappa-B)-mediated survival pathway as well as the PI3K (phosphoinositide 3-kinase)/Akt signaling pathway. Breast cancer cells can also be sensitized to estrogen-induced apoptosis through suppression of glutathione by BSO (L-buthionine sulfoximine). This finding has implications for the control of breast cancer with low-dose estrogen and other targeted therapeutic drugs

Exploring new physics frontiers through numerical relativity

The demand to obtain answers to highly complex problems within strong-field gravity has been met with significant progress in the numerical solution of Einstein's equations - along with some spectacular results - in various setups. We review techniques for solving Einstein's equations in generic spacetimes, focusing on fully nonlinear evolutions but also on how to benchmark those results with perturbative approaches. The results address problems in high-energy physics, holography, mathematical physics, fundamental physics, astrophysics and cosmology

TYPING OF HUMAN GROUP-A ROTAVIRUS WITH ALKALINE PHOSPHATASE-LABELED OLIGONUCLEOTIDE PROBES

Rotavirus (RV) in stools of childre

Development of hypertension over 6 years in a birth cohort of young middle-aged men: the Cardiovascular Risk Factor Study in southern Sweden (CRISS).

OBJECTIVES: To explore the development of hypertension (HT) in a cohort of young middle-aged men. DESIGN: Prospective birth-cohort study of men surveyed over 6 years. SETTING: Helsingborg County Hospital, Sweden, 1990-97. SUBJECTS: A total of 628 men born in 1953-54, all surveyed at 37, 40 and 43 years of age. MAIN OUTCOME MEASURES: Systolic blood pressure (SBP), diastolic blood pressure (DBP), S-cholesterol, body mass index (BMI), alcohol consumption, ethnicity. HT was defined as SBP > or = 140 mmHg and/or DBP > or = 90 mmHg, or ongoing treatment. Using SBP < 130 mmHg and DBP < 85 mmHg as reference, the odds of conversion to HT in men with high normal blood pressure (BP) (SBP 130-139 mmHg and DBP 85-89 mmHg) was investigated. RESULTS: At age 37, 243 men (39%) had reference BP, 167 (26%) had high normal BP and 218 (35%) were hypertensive. Corresponding numbers at age 40 were 265 (42%), 166 (27%) and 197 (31%); and at age 43, 180 (29%), 142 (22%) and 306 (49%), respectively. High normal BP at baseline was associated with the development of HT both at age 40 (odds ratio (OR)=2.45 confidence interval (CI): 1.42-4.22) and at age 43 (OR=2.46, CI: 1.59-3.80), independent of other cardiovascular disease risk factors and ethnicity. The progression to HT was predicted also by S-cholesterol, alcohol consumption, BMI and weight gain. CONCLUSIONS: Over a short-term period, a substantial proportion of young middle-aged men with high normal BP develop HT with overweight and alcohol consumption as important determinants. These findings have implications for the prevention, screening and medical care of HT in this target population