acacia nilotica (thorn mimosa) is used locally for various medicinal purposes by traditionalists and herbalists in northeastern nigeria. plants products have been used since ancient times in the management of various conditions. the bark of a. nilotica has been reported to be used traditionally to manage diabetes, dysentery, leprosy, ulcers, cancers, tumor of the eye, ear and testicles, indurat...

objective: bleaching of the teeth is considered as a safe, effective, and conservative procedure to treat discolored teeth. the aim of the present study was to compare the amount of mercury and silver released from amalgam after applying two brands of carbamide peroxide 16% bleaching gel. materials and methods: for this experimental study, 384 amalgam tablets were prepared. the samples were kep...

exposure to mercury (hg) as a heavy metal can cause health effects. the objective of this study was to assess occupational exposure to hg in a chlor-alkali petrochemical industry in iran by determining of hg concentrations in air, blood and urine samples.the study was performed on 50 exposed subjects and 50 unexposed controls. air samples were collected in the breathing zone of exposed subjects...

We describe a simple experiment that demonstrates one-dimensional laser cooling in a sealed vapor cell. A velocity selective optical pumping scheme was first used to define a collimated beam of atoms within the cell. A particular velocity group of atoms was labeled by optical pumping with one laser and detected by absorption with a second laser. Transverse cooling of this velocity group, which ...

We demonstrate the use of cylindrical vector beams - beams with spatially varying polarization - for detecting and preparing the spin of a warm rubidium vapor in a spatially dependent manner. We show that a modified probe vector beam can serve as an atomic spin analyzer for an optically pumped medium, which spatially modulates absorption of the beam. We also demonstrate space-variant atomic spi...

We demonstrate coherent control of single-photon absorption and reemission in a two-level cold atomic ensemble. This is achieved by interfering the incident single-photon wave packet with the emission (or scattering) wave. For a photon with an exponential growth waveform with a time constant equal to the excited-state lifetime, we observe that the single-photon emission probability during the a...

Knowledge of Hg speciation in tissue is valuable for assessing potential toxicological effects in fish. Direct Hg analyzers, which use thermal decomposition and atomic absorption spectrometry, have recently gained popularity for determining organic Hg after procedural solvent extraction from some environmental media, although quantitative recovery from lipid-rich materials, such as fish liver, ...

The activity of polonium (210)Po and uranium (234)U, (238)U radionuclides, as well as trace metals in mosses, collected from Sobieszewo Island area (northern Poland), were determined using the alpha spectrometry, AAS (atomic absorption spectrometry) and OES-ICP (atomic emission spectrometry with inductively coupled plasma). The concentrations of mercury (directly from the solid sample) were det...

We study how coherent Stokes and anti-Stokes Raman scattering influence coherent population trapping. In an experiment using an atomic sodium vapor cell we observe induced transparency, induced absorption, and gain features, all of subnatural linewidth. The electromagnetically induced resonance is a peak or a dip depending on which side of the optical transition the fields are tuned to, and thu...

This paper reports on the design and implementation of thin film multilayer dielectric to form Bragg reflectors on the sidewalls of micromachined atomic cells. Due to deposition shadowing, significant variations in the thicknesses of the thin films are encountered when the layers are deposited using PECVD. These gradients in thickness may limit optical performance of the reflector in atomic cel...