Introduction: Usually osseointegration takes between three to six months after implant placement but patients are interested to have early loading. There are no definitive criteria for measuring bone mineral density (BMD), insertion torque (IT) (final torque force) and resonance FREQUENCY analysis (RFA) (primary implant stability) to determine exact loading time based on the relationship between the above-mentioned parameters. The aim of this study was to determine the relationship between IT, RFA and BMD in screw-type implants.Materials and Methods: This clinical trial was conducted on 18 patients who were candidates for ITI implant placement. Written consent was taken and jaw bone density was determined via a digital radiography technique before surgery. After implant placement, RFA and IT were measured. Fifty-five ITI implants of the total 62 implants placed were evaluated; the implants were 12 mm long with a diameter of 4.1 mm. Data was analyzed with Pearson’s test using SPSS.15 software (a=0.05).Results: There was a significant relationship between IT, RFA and BMD. Pearson’s test showed a correlation coefficient of 0.872 to 0.789 between the three parameters, indicating a strong relationship between them. The mean bone density was 1.468±0.042 g/cm2; the mean RFA was 66.01±2.2 ISQ and the mean IT was 34.62±3.33 N/cm2.Conclusion: Based on the results of the present study there is a significant relationship between, IT, RFA and BMD (p value=0.001).

Background: Tympanometry is one of the most important audio logical tests for the assessment of neonatal hearing screening programs. This test is usually done using a 226 Hertz probe tone; however, in infants less than 6 months of age, using this probe tone FREQUENCY is not reliable due to the different characteristics of the middle ear compared to adults. The purpose of this study was to assess the obtained tympanometric data in neonates 1 to 14 days with normal hearing using 226, 678, 800 and 1000 Hertz FREQUENCY probes tones.Materials and Methods: In this cross-sectional study, 30 neonates aged 1 to 14 days who were diagnosed as normal in hearing aspect with using otoacoustic emissions test, were assessed by tympanometry. Tympanometric tests were performed using 226, 678, 800 and 1000 Hertz FREQUENCY probe tones for both ears. For data analysis, the T-paired method has been used.Results: With using 226 Hertz FREQUENCY probe tone, incidence of unusual double peak tympanograms was observed in 65% of cases, which with increasing FREQUENCY of the probe tone, this percentage was decreased. There was also a statistically significant difference between the static admittance peak compensated in two 226 and 1000 Hertz FREQUENCY probes tones.Conclusion: In neonates with normal hearing and without any risk factors for hearing loss, the 1000-Hertz Tympanogram shows a better middle ear status than the 226-Hertz tympanogram.

Background & objective: Industrial development towards digital technologies has reduced the occupational exposure to high sound pressure levels. Meantime, exposure to LOW levels of annoying LOW FREQUENCY Noise (e.g.=LFN) had become a main concern. Since LFN may be experienced not only in working premises, but also in residential areas, offices, and control rooms, its effects on mental performance have been studied by many researches. This issue has been documented by world health organization. Present study reviewed articles published on the effects of LOW FREQUENCY noise on mental performance due to the controversial results obtained by different studies.Method: More than 90 papers published in national and international journals on mental efficiency, fatigue, and other health effects of LOW FREQUENCY noise and their influencing factors were reviewed.Results: Reviewing the published articles revealed that LFN at LOW levels increases the responding time and hampers speed of learning comparing with the same level of wide band noise. LOW FREQUENCY noise reduces the mental performance in the tests where high attention and carefulness are demand.Conclusion: LOW FREQUENCY noise has higher influencing risk in comparison with the reference noise and therefore, more attention should be paid to LFN in occupational exposure evaluations.

Drought is one of the natural hazards which have serious effects on human life, and environment. This phenomena has a complicated mechanism that its nature had been little-known. Accurate estimation of LOW fLOW as an index in water resources management has a great importance. Because of the complicated nature of LOW fLOWs, a few numbers of studies conducted in this field of study, and the FREQUENCY analysis of LOW fLOW is of interest to researchers. Therefore, in the present study, the FREQUENCY of LOW fLOWs in the Dez river basin with different durations (7, 10, 15, 30, 60 and 95 days) were done using the distribution functions of the Normal (NOR), Log-Normal (LN), Pearson Type III (P3), Exponential (EXP), Gamma (GAM), Generalized Extreme Value (GEV), Nakagami (NAK), Rayleigh (RAY), Logistic (LOG), Generalized Logistic (GLOG), Generalized Pareto (GPA) and Weibull (WEI). Before fitting the statistical distribution functions on LOW fLOW series, the homogeneity and stationarity of LOW fLOW series in the Dez river basin were investigated by Augmented Dickey - Fuller (ADF) and modified Mann-Kendall tests, respectively. The results of these tests confirmed the homogeneity and stationarity of used data series. In the next step, above mentioned distribution functions were fitted on LOW fLOW series and the goodness of fit were evaluated by normalized root mean square error and Nash- Sutcliffe criteria. The results reveal that the LOG and GEV distribution functions were the best fitness on LOW fLOW series in the Dez river basin. The Normal distribution has also good performance in estimating the LOW fLOW and because of its easier application can be considered as an alternative for estimating LOW fLOW in the Dez river basin by acceptable error.