Aims The use of intrauterine devices (IUDs) has been one of the most effective, the safest and cost-effective methods for preventing pregnancy, for a long time. However, some complications have been reported for IUDs. The complications may be reduced by using a specific technique for placement of IUD. The objective of this study was to introduce the rotating withdrawal technique for the first time, which was investigated to reduce the complications of IUD insertion. Materials & Methods This historical cohort study was conducted on 1199 females who referred to Sarem Medical Center for IUD insertion from 1984 to 1995. After primary examinations, IUD was inserted by rotating withdrawal technique. The subjects were followed up for 2 years. Findings Displacement was observed just in 20 cases (1. 67%). All of them were seen in the first month after placement. For these cases, IUD insertion was done again. After the second replacement, displacement was observed in 4 cases (0. 035%) after one month. Therefore, it was recommended to them to use another preventive method. There was no pregnancy or displacement in the other cases during 2 years. Conclusion The rotating withdrawal technique can minimize the pregnancy rate when IUD is used. In addition to the type and quality of IUD, insertion method of IUD can increase its effectiveness.

In this paper, a new method for extending and relaxing the noise-coupling (NC) technique is proposed to enhance the noise-shaping order without adding the number of integrators. The noise-shaping order of the introduced ∑∆ modulator whit applying a second-order noise-coupling technique is enhanced and its performance with optimizing the noise transfer function (NTF) zeros is improved. Also, by removing the analog adder at feedforward path and transferring it to a new feedback branch before the last integrator and adding second-order NC path can be decreased the input voltage swing to the quantizer. Thus, by improving the modulator resolution, power consumption can be reduced. Mathematical analyses and behavioural simulation results confirm the effectiveness of the new NC method. To examine its performance, a 2nd-order single loop ΣΔ modulator was designed. The new noise-coupling method is used to achieve the three-order noise shaping to increase the resolution with low complexity and low-power. The results show an outstanding improvement in signal-to-noise and distortion ratio (SNDR) compared to the conventional structure.

High gain Balun-low-noise-amplifier (LNA) is proposed for tuner of digital televisions (DTVs). The proposed Balun-LNA is based on CS-CG (common-source-common-gate) structure. To improve the isolasion and frequency response, Balun-LNA has cascode transistors before load resistors. Balun-LNA uses current-bleeding circuit to increasie transconductance of CS transistor, so that current-bleeding transistor has transconductance of N-1 times larger than transconductance of cascode transistor. Thereby, transconductance and current of CS transistor are increased N times, as N-1 times of current pass to current-bleeding transistor. Therefore current of CG and CS stages stay identical. Also, Balun-LNA employs a positive feedback to satisfy input impedance matching and CG transistor has higher transconductance. By increasing transconductance of CS and CG transistors, the proposed Balun-LNA achieves to high voltage gain. Accordingly, CG and CS tansistors have symmetrical currents and loads at the differential output of the proposed Balun-LNA. Symmetrical loads cause the balanced differential outputs. This proposed Balun-LNA is designed in 90-nm CMOS technology and covers the frequency range of 40 MHz to 1GHz. This Balun-LNA achieves the voltage gain of 22.6 dB, S11 of less than -10 dB and the Minimum NF of 5 dB. This Balun-LNA operates at the nominal supply voltage of 2.2v.

In this paper, a novel LNA design based on improved noise cancellation technique in the frequency range of 27 to 31 GHz.is presented The proposed LNA is suitable for millimeter wave 5G wireless communication. The first stage of this two-stage LNA is designed with noise cancelation approach to decrease the noise figure of the system. In order to improve the design method, we utilizes a negative feedback by implementing a couple inductor with a transformer connection. The negative feedback provides an acceptable input matching and control the gain to increase the band width. The cascode structure is used in the second stage for its higher gain and stability and better reverse isolation at millimeter wave frequency. Furthermore, an inductor is utilized to boost the gain with neutralizing the capacitance of node between two transistors in a cascode structure. The CMOS silicon on insulator (SOI) is utilized to provide a high level of integration and low power consumption with the minimum cost. The proposed LNA is designed with 130 nm CMOS technology and has 22.14 dB gain with 1.86 dB noise figure at 29 GHz. The 3-dB bandwidth of the designed LNA is 4 GHz (14%) and its DC power consumption is 33.4 mW. The IIP3 is -16dBm and input reflection coefficient is better than -10dBm in the frequency range of interest. The proposed LNA is simulated by ADS software.

Introduction: In order to manage a patient, doctors and medical students need to collect the patient's data and information in different ways, evaluate, interpret, analyze and reason clinically, and after diagnosis, take action to solve the patient's problem. For this purpose, it is necessary for them to go through the levels of knowledge in three categories: remembering, interpretation and problem solving. Materials & Methods: In this area, we intend to introduce a case-based replacement technique to our audiences. We have named this method TTT or (Triple Taxonomy Tests / technique) or MTQ (Mixed Taxonomy Questions). Results: In this way, a case is designed with a number of questions and a number of options and blank spaces, based on three levels of "recall", "interpretation" and "problem solving". This form of test or case-based technique is used in self-learning exercises, self-assessment or official assessments Conclusion: This test helps us to improve the ability to use "thinking", clinical decision-making and solving problems in real patient cases.

Case Description: In this present study three cases of perineal hernia in dogs have been presented and new concepts in perineal herniorrhaphy have been introduced. A 5-year-old intact male Spitz dog, a 6-year-old intact male dachshund dog and a 4.5-year-old sexually intact male Welsh corgi dog were referred with swelling around the anus and dyschesia.Clinical Findings: The owner complained about a sudden enlargement of the right perineal region. Physical examination revealed soft bulged area surround and in the right side of anus. Plain radiograph showed normal position of urinary bladder and prostate.Treatment and outcome: All the dogs were treated surgically by the internal obturator muscle flap technique which were transposed dorso-medially into the defect and sutured into defect borders. No complication was observed after surgery in any of the dogs. The dogs were monitored weekly for one month. The final evaluation revealed that all dogs were clinically normal and the owners were fully satisfied with the outcome.Clinical Relevance: This study proved that the internal obturator transposition technique was superior technique for perineal hernia cases among all suggested techniques.

Purpose: Time is a key structural component of our lives and the world. It is therefore not surprising that consumers engage in their daily consumption choices and activities with multiple time orientations - past, present and future. In industrial procurement, information retrieval describes the action that a buyer takes to access all relevant information sources for a purchasing decision, often involving data from a variety of sources in which time plays a more effective role. Therefore, the purpose of this study is to evaluate the effect of time on consumer behavior with emphasis on industrial goods. Research Methodology: This research has used a combined approach to investigate the effects of time on consumer behavior. The research method is a one-way mix for collecting and analyzing quantitative and qualitative data in a study or a set of studies that is based on the priority and sequence of information. In this research, first the qualitative approach is then quantitative. To solve the research problem in the qualitative stage, the meta-combined approach has been used. Results: In this study, the seven-step method of Sandlowski and Barroso (2007) was used, which finally presented the effects of time on consumer behavior in three psychological, economic and social dimensions. Psychological dimension including 11 components, economic dimension 7 components and social dimension 6 components were identified. In this paper, the prioritization of the identified components of meta-combination with two approaches of Demetel and ANP is presented and 12 experts were used to determine the sub-criteria. Findings: The results of the study can be a guide for marketers and marketing managers, and by considering the components identified in this study, they can take a big step in advancing their goals and pave the way for achieving the goals.

Artificial immune system (AIS) is one of the most meta-heuristic algorithms to solve complex problems. With a large number of data, creating a rapid decision and stable results are the most challenging tasks due to the rapid variation in real world. Clustering technique is a possible solution for overcoming these problems. The goal of clustering analysis is to group similar objects. AIS algorithm can be used in data clustering analysis. Although AIS is able to good display configure of the search space, but determination of clusters of data set directly using the AIS output will be very difficult and costly. Accordingly, in this paper a two-step algorithm is proposed based on AIS algorithm and hierarchical clustering technique. High execution speed and no need to specify the number of clusters are the benefits of the hierarchical clustering technique. But this technique is sensitive to outlier data. So, in the first stage of introduced algorithm using the proposed AIS algorithm, search space was investigated and the configuration space and therefore outlier data are determined. Then in second phase, using hierarchical clustering technique, clusters and their number are determined. Consequently, the first stage of proposed algorithm eliminates the disadvantages of the hierarchical clustering technique, and AIS problems will be resolved in the second stage of the proposed algorithm. In this paper, the proposed algorithm is evaluated and assessed through two metrics that were identified as (i) execution time (ii) Sum of Squared Error (SSE): the average total distance between the center of a cluster with cluster members used to measure the goodness of a clustering structure. Finally, the proposed algorithm has been implemented on a real sample data composed of the earthquake in Iran and has been compared with the similar algorithm titled Improved Ant System-based Clustering algorithm (IASC). IASC is based on Ant Colony System (ACS) as the meta-heuristics clustering algorithm. It is a fast algorithm and is suitable for dynamic environments. Table 1 shows the results of evaluation. The results showed that the proposed algorithm is able to cover the drawbacks in AIS and hierarchical clustering techniques and the other hand has high precision and acceptable run speed.