This paper proposes a 2.4 GHz active mixer without passive inductor for the transceiver system. Taking into account the design requirements of the mixer, a double-balanced down-conversion structure with active inductor and negative resistance is designed. The proposed mixer with 130 nm CMOS technology is designed and simulated using Cadence software at 1.5 V supply voltage. Although we had to compromise conversion gain with linearity, we were able to achieve very high conversion gain with average linearity. Based on the results of post-layout simulations, the conversion gain of 27.57 dB, IIP3 equal to -7.88 dBm, 1-dB compression point equal to -17.34 dBm and IIP2 equal to 44.22 dBm with power consumption of 2.5 mW was obtained for the proposed mixer. The chip size without input and output pads is 95.18 µm × 117.68 µm, which leads to a chip area of 0.0112mm2.

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.