Associations of tobacco use, physical activity and diet with hypertension in the city of Kandahar, Afghanistan: a community-based cross-sectional study.

Objective: Hypertension exerts a substantial financial burden on individuals, families, communities, and the health system of a country. The current study aimed to describe the association of hypertension with its main risk factors in the Afghan population living in Kandahar city.

Results: The prevalence of tobacco smoking, naswar use, physical activity and a healthy diet was 22%, 55%, 63.

Diffractionless transmission of optical beams through a four-level atomic system affected by a plasmonic nanostructure.

A nondiffracting propagation of an optical beam through a four-level double-V-type quantum system near a plasmonic nanostructure is investigated. We study the linear absorption and dispersion properties of the quantum system as it interacts with two laser fields. We discuss the effect of the control beam with a Laguerre-Gaussian (LG) profile on the focusing of the probe beam in the presence of a plasmonic nanostructure.

Knowledge, attitudes and practices of university students toward COVID-19 in Southern region, Afghanistan: a cross-sectional study.

Background: Successful implementation of preventive measures and level of awareness in particular among university students in Afghanistan could play a crucial role in spreading the information for better control of the ongoing pandemic. Therefore, the aim of this study was to determine the level of knowledge, attitudes and practices (KAP) regarding COVID-19 among Kandahar university students.

Methods: A cross-sectional study conducted among undergraduate students to investigate their KAP regarding COVID-19 from January to March, 2021.

Controllable Hartman effect by vortex beam in a one dimensional photonic crystal doped by graphene quantum dots.

The Hartman effect is studied in a one dimensional photonic crystal doped with graphene quantum dots. It is shown that the Hartman effect can be switched from negative to positive by increasing the Rabi-frequency of the controlling field and also by manipulating the relative phase of the applied fields. The effect of the vortex beam on the Hartman effect is also presented.

Narrow-band transmission filter based on 1D-PCs with a defect layer.

A narrow-band transmission filter based on one-dimensional photonic crystals with /() layers is grown by sol-gel spin-coating processing. The structural and optical properties of fabricated samples are characterized by an atomic force microscope, scanning electron microscope, and UV-visible spectroscopy. Specific wavelength transmission and bandgap in the optical filter with and without a defect layer have been investigated by engineering the layer thickness and defect layer material.