Introduction:Noise in dental offices is one of the risk factors in the workplace. One of the major effects of noise is hearing loss. This study aimed to determine the effects of noise on hearing thresholds of dentists of Babol city. Methods:This descriptive analytical cross-sectional study was performed on 40 dentists in Babol City (as case group) and 40 office workers (as control group). He...

Dean E. Riechers Corresponding author. Department of Crop Sciences, University of Illinois, Urbana, IL 61801; [email protected] Two studies investigated off-target exposure of soybean to plant growth regulator (PGR) herbicides and determined if simultaneous exposure to PGR herbicides and labeled soybean herbicides increase PGR injury. The PGR herbicides, 2,4-D, clopyralid, and dicamba, as well ...

in order to evaluation of rice stem borer's damage (chilo suppressalis walker), on rice ‎cultivars an experiment was carried out by two factors, (three cultivars and five spraying times), in ‎completed randomized block design an factorial sampling was conducted on the hills infested to ‎deadhearts (d.h), whiteheads (w.h) and yield loss. five hills were randomly selected from each plot ‎and...

We consider the harvesting of a population in a stochastic environment whose dynamics in the absence of harvesting are described by the logistic Verhulst-Pearl model. Using ergodic optimal control, we find the optimal harvesting strategy which maximizes the asymptotic yield of harvested individuals. To our knowledge, ergodic optimal control has not been used before to study harvesting strategie...

Many listeners with hearing thresholds within the clinically normal range nonetheless complain of difficulty hearing in everyday settings and understanding speech in noise. Converging evidence from human and animal studies points to one potential source of such difficulties: differences in the fidelity with which supra-threshold sound is encoded in the early portions of the auditory pathway. Me...

to evaluate the effect of different rates of nitrogen fertilizer on competitive ability of canola (okapi cv.) in interference with wild mustard, a split-plot experiment based on a randomized complete block design with 3 replications was carried out at agricultural faculty of bu-ali sina university, in 2008-2009. 4 levels of nitrogen fertilization (100, 150, 200 and 250 kg n ha-1) were assigned ...

the adequacy of the swat model in the estimation of runoff, sediment yield and nitrate loss in the gorganrood watershed was tested, using the existing spatial database as the primary data. the model was then executed for a 31-years’ time period. in combination with the swat model, the sequential uncertainty fitting program (swat-cup and sufi-2) was added used to calibrate and validate a hydrolo...

in this study, ice-glazing process of frozen shrimp by chitosan was applied to protect the frozen shrimp from undesirable chemical and physical changes. the effects of 2% chitosan solution glazing on quality of whole, raw and cooked (without head, tail and shell) shrimps stored at -18±2ºc for 6 months were investigated and compared with water glazing, sodium metabisulfite treatment control. gla...