Observations of high-redshift supernovae indicate that the Universe is accelerating. Here we present a model-independent method for estimating the form of the potential V(phi) of the scalar field driving this acceleration, and the associated equation of state w(phi). Our method is based on a versatile analytical form for the luminosity distance D(L), optimized to fit observed distances to dista...

Intracellular pH (pHi) has been measured in Dictyostelium discoideum cells by 31P nuclear magnetic resonance. Ax2 cells, newly harvested from growth medium, maintained a pHi of 7.33 +/- 0.04 (17) at an extracellular pH ranging from 3.5 to 6.5. Below pH 3.5 the cells tend to lyse, whereas at pH values above 6.5 their pHi rises though they remain viable. pHi regulation in acid medium is not depen...

BACKGROUND The widespread use of nutritional supplements among athletes is poorly understood. The prevalence of supplement intake and users' knowledge have been researched independently leading to useful, but disconnected, information on supplement use. METHODS The 'UK Sport 2005 Drug Free Survey' data (n = 874) were re-analysed using association [chi2] and 'strength of association' tests [ph...

Although impairment of splanchnic perfusion may induce mucosal hypoxia and endotoxaemia during orthotopic liver transplantation (OLT), little is known about the changes in mucosal oxygenation during and after the procedure. To study the effects of liver surgery itself on mucosal pH (pHi) and the response of pHi to acute changes in portal flow, we measured gastric pHi during six liver resections...

Many efforts to reduce prostate specific antigen (PSA) overdiagnosis and overtreatment have been made. To this aim, Prostate Health Index (Phi) and Prostate Cancer Antigen 3 (PCA3) have been proposed as new more specific biomarkers. We evaluated the ability of phi and PCA3 to identify prostate cancer (PCa) at initial prostate biopsy in men with total PSA range of 2-10 ng/ml. The performance of ...

We have studied the effect of infection with the blood-stage of Plasmodium yoelii 17X, a nonlethal parasite, on plasma membrane antigens, receptors, and secretory properties of macrophages (M phi) in murine liver, spleen, and blood. mAb F4/80 (M phi specific), F7/4 (a marker for immature and immunologically activated M phi, as well as neutrophils), and Mac-1, which binds to the type 3 complemen...

OBJECTIVE To answer the questions: (a) What is the effect of hypertrophy on the intracellular pH (pHi) and buffering power of cardiac muscle, and (b) How does hypertrophy affect the ability of cardiac muscle to recover from intracellular acidosis induced by hypoxia. METHODS In nominally HCO3(-)-free, HEPES-buffered Tyrode solution (35 degrees C), pHi and the intrinsic buffering power (beta i,...

Intracellular pH (pH1) of sea urchin eggs and embryos was determined using DMO (5,5-dimethyl-2,4-oxazolidinedione). By this method, the pH1 of Lytechinus pictus eggs increased after fertilization from 6.86 to 7.27, and this higher pHi was maintained thereafter, as has been previously observed with pH microelectrodes. The same general result was obtained with the eggs of Strongylocentrotus purpu...