A “Hidden Epidemic” The public is largely unaware of the serious health consequences and financial costs associated with the high prevalence of STDs in the United States. To call attention to this “hidden epidemic” and to study ways to address the problem, the Institute of Medicine (IOM) in 1994 convened a 15member expert panel. Its mandate was to “(a) examine the epidemiological dimensions of ...

Enzymes are biological catalysts vital to life processes and have attracted century-long investigation. The classic Michaelis-Menten mechanism provides a highly satisfactory description of catalytic activities for large ensembles of enzyme molecules. Here we tested the Michaelis-Menten equation at the single-molecule level. We monitored long time traces of enzymatic turnovers for individual b-g...

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HE 0141–3932 (zem = 1.80) is a bright blue radio-quite quasar with an unusually weak Lyα emission line. Large redshift differences (∆z = 0.05) are observed between high ionization and low ionization emission lines. Absorption systems identified at z abs = 1.78, 1.71, and 1.68 show mild oversolar metallicities (Z ≈ 1 − 2Z⊙) and can be attributed to the associated gas clouds ejected from the circ...

Starting from metric of general nonextreme stationary axisymmetric black hole in four-dimensional spacetime, both statistical-mechanical and thermo-dynamical entropies are studied. First, by means of the " brick wall " model in which the Dirichlet condition is replaced by a scattering ansatz for the field functions at the horizon and with the Pauli-Villars regularization scheme, an expression f...

In recent months I have come across many instances in which someone has found what they believe is a new result, in which they evaluate in closed form a sum involving binomial coefficients or factorials. In each case they have managed to do that either by using the recent powerful method of Wilf and Zeilberger (the W–Z method) [6], or by comparing coefficients in some ad hoc algebraic identity....