RF Energy Harvesting System and Circuits for Charging of Wireless Devices Using Spectrum Sensing

Recently, lots of works have been done on the optimal power management of wireless devices. This leads to the main idea of ambient energy harvesting. Among various energy harvesting approaches, one is to use radio waves existing in the ambient environment for battery charging, called RF energy harvesting. In this chapter, in order to improve the RF energy harvesting performance, we utilize spectrum sensing to allow the wireless devices to select the frequency band with maximum power that exceeds a predefined threshold to charge the device (this power threshold can be determined according to battery type and its required charging power) and the device can use this power for battery charging. Also, a novel voltage multiplier circuit is proposed. By means of simulations and experimental tests, it can be seen that after detection of our desired 1 mW RF signal, system output power is about 532μ W and 450μ W in simulation and practical situations respectively

Investigation of breast cancer screening among the women of Khorramabad (west of Iran): A cross-sectional study

Abstract. Breast cancer is the most common women's cancer that more than 90% of the patients can be treated or even cured through early diagnosis. So we intend to investigate the status of breast cancer screening in Khorramabad, a city in the west of Iran. In the present cross-sectional study, the study population included 457 number of 20 to 65 year old women referring to the health centers of Khorramabad during the second half of 2015 to receive health care services. The sampling method was multistage random-cluster. A multi-part questionnaire were used. Fisher exact test, chi-square and independent t tests were used to analyze the data.  The regular self-breast exam (SBE) had been carried out by 12.3% of the women, visiting doctors for regular clinical breast exam (CBE) had been done by 6% of the respondents and regular mammography every one to two years had been performed by 2.4% of the women. A statistically significant relationship was seen between occupation (P = 0.001), regular consumption of contraceptive pills (P = 0.032), history of breastfeeding, history of breast cancer in the first degree relatives (P = 0.001), and a history of cancer in the second degree (P = 0.005) relatives, and the regular SBE. Planning to enhance the women's awareness about breast cancer and the methods of early diagnosis and designing educational programs can be an important step to reduce deaths and disabilities caused by this disease among the women in such deprived cities

Impaired aortic distensibility measured by computed tomography is associated with the severity of coronary artery disease.

Impaired aortic distensibility index (ADI) is associated with cardiovascular risk factors. This study evaluates the relation of ADI measured by computed tomographic angiography (CTA) with the severity of coronary atherosclerosis in subjects with suspected coronary artery disease (CAD). Two hundred and twenty-nine subjects,age 63 ± 9 years, 42% female, underwent coronary artery calcium (CAC) scanning and CTA, and their ADI and Framingham risk score (FRS) were measured. End-systolic and end-diastolic (ED) cross-sectional-area(CSA) of ascending-aorta (AAo) was measured 15-mm above the left-main coronary ostium. ADI was defined as: [(Δlumen-CSA)/(lumen-CSA in ED × systemic-pulse-pressure) × 10(3)]. ADI measured by 2D-trans-thoracic echocardiography (TTE) was compared with CTA-measured ADI in 26 subjects without CAC. CAC was defined as 0, 1-100, 101-400 and 400+. CAD was defined as luminal stenosis 0, 1-49% and 50%+. There was an excellent correlation between CTA- and TTE-measured ADI (r(2)=0.94, P=0.0001). ADI decreased from CAC 0 to CAC 400+; similarly from FRS 1-9% to FRS 20% + (P<0.05). After adjustment for risk factors, the relative risk for each standard deviation decrease in ADI was 1.66 for CAC 1-100, 2.26 for CAC 101-400 and 2.32 for CAC 400+ as compared to CAC 0; similarly, 2.36 for non-obstructive CAD and 2.67 for obstructive CAD as compared to normal coronaries. The area under the ROC-curve to predict significant CAD was 0.68 for FRS, 0.75 for ADI, 0.81 for CAC and 0.86 for the combination (P<0.05). Impaired aortic distensibility strongly correlates with the severity of coronary atherosclerosis. Addition of ADI to CAC and traditional risk factors provides incremental value to predict at-risk individuals

The relationship between mental workload and general health among welders of Tehran Heavy Structure Metal Company

Mental workload is one of the factors that influence individuals’ performance in the work environment as well as their efficiency and productivity. The present study aimed at examining the association between mental workload and general health among welders of Tehran Heavy Structuress Metal Company.This cross-sectional study was conducted in 2016. The sample included 100 welders who were working in Tehran Heavy Structures Metal Company. Sampling was done through conducting a census. A demographic questionnaire, General Health Questionnaire-28 (GHQ-28), and National Aeronautics and Space Administration Task Load Index (NASA-TLX) mental workload questionnaire were used to collect data. The obtained data were fed into SPSS (version 22) and analyzed through Chi-square, one-way ANOVA, Kruscal Wallis Test, Pearson product moment correlation, and Mann-Whitney U Test.The results showed that the participating welders had an average age of 36.16±7.81, an average work experience of 9.65±5.83, and a BMI of 25.95±3.39 kg/m2. The mean and standard deviation of the overall score of welders’ mental workload were 65.88±21.15. The cut-off scores for the total mental workload questionnaire and the subscales were respectively set at 23 and 6. The results demonstrated that 26% of the welders were suspected of mental disorder. Furthermore, the results of Pearson correlation indicated that there was no significant relationship between the overall score of NASA mental workload and that of general health (p-value>0.05).Welders’ mental workload is relatively high. Therefore, further research should be conducted in order to identify main risk factors that lead to mental and health disorder. Future studies should also be performed to present some solutions for te purpose of decreasing or preventing these side effects among welders as much as possible.

Motivation-based Market Segmentation in Rural Tourism: the Case of Sámán, Iran

Market segmentation is a pivotal and under-investigated issue when evaluating decision-making processes and motivational factors shaping rural tourism. The present study has examined market segments of rural tourists in Iran based on their socio-demographic attributes, travel characteristics and preferred leisure activities, profiling rural tourists on the base of their motivational background. The survey results indicated that rural tourism in the study area is a heterogeneous market, whose development depends on general trends in Middle East tourism market. A comprehensive knowledge of rural tourism actors may help formulating appropriate marketing strategies for internal areas destined to tourism growth

Zoning areas prone to fire occurrences in the forest ecosystems of North Zagros (Case study: Sardasht forests in West Azarbaijan)

The ecological balance in nature is integrated with forest safety. Wildfire causes irreparable effects on the ecological functions of the forest and disrupts the production of oxygen and carbon sequestration, reducing biodiversity, expanding pests and diseases, and eventually breaking the balance of nature, which is the unique role of the forest. The purpose of this study was to identify the factors affecting the occurrence and zoning of fire hazards in Sardasht forests in the area of 1784.8 hectares to achieve control and counteraction strategies. At first, layers of elevation, slope, aspect, precipitation, temperature, organic carbon, soil texture, and vegetation cover were mapped for the study area. AHP was used for prioritization, evaluation criteria, and weighting of the layers. Finally, the classifications of the layer were done using GIS, and hazard scores were classified at four classes included; Safe, low risk, medium risk, and high risk. The results showed that 12.7% of the study area is at high risk, 39.9% has moderate risk, 31.9% is in the low-risk area and 15.5% is located in the safe area. Also, the Angstrom index was showed that wildfire occurring has maximum possibility between June to September. It was also found that the north-east of the study area is more at risk of fire due to the denser vegetation than other areas. The minimum fire hazard was observed in the north, part in the south, and the narrow strip in the central regions of the study area

Influences of Permeate Pressure and Feed Flow Rate on Benzene Removal from Gasoline by Pervaporation

In this work, the effects of permeate pressure and feed flow rate on the performance of a composite polyvinyl alcohol (PVA) membrane in the removal of benzene from gasoline by pervaporation (PV) were evaluated. The results indicate the remarkable effect of permeate pressure on membrane performance as reducing permeate pressure (higher vacuum) from 30 to 3 mmHg causes the total flux to increase from 6.6 to 51.7 g/hrm2 and from 12.2 to 79 g/hrm2 at 25 and 35 °C respectively. Furthermore, increasing feed flow rate enhances total flux and diminishes the amount of benzene in retentate (product) only below 1000 ml/min and has a negligible effect at higher flow rates

Preferensi Pegawai UIN-SU Dalam Menabung Di Bank Syariah

This research aims to know the: (1) partially there was significant influence between the religious factor, economic interests and against the preference of employees of UIN-SU in saving in Islamic banks, and (2) simultaneous significant influence among religious factors, economic interests and against the preference of employees of UIN-SU in saving in the Islamic bank. This research uses a quantitative research method. A quantitative approach is an approach that emphasizes on testing theories or hypotheses through measurements of the variables research in numbers and perform data analysis with statistical procedures. The research design used the design quantitative research using multiple linear regression analysis technique is supported by a test model and statistical tests. This paper give For variables of interest and economic variables have no significant influence on the trend of saving

Effect of Testosterone Enanthate Modeling of Polycystic Ovary on Liver Irs-2 mRNA Expression in Rats: A Brief Report

هناك العديد من النماذج الحيوانية لتكيس المبايض (PCO). يعد استخدام إينونثات التستوستيرون الخارجي إحدى طرق تحريض هذه النماذج. ومع ذلك ، يجب أيضًا دراسة تحريض مقاومة الأنسولين في تقنيات النماذج. لذلك ، تهدف الدراسة الحالية إلى التحقق من تعبير ركيزة مستقبلات الأنسولين (Irs) -2 mRNA في أنسجة الكبد لنموذج PCO الفئران. تم تقسيم تسعة عشر من قئران ويستار إلى ثلاث مجموعات. (1) تلقت مجموعة نمذجة PCO (N = 7) يوميًا 1.0 مجم / 100 جرام من إينونثات التستوستيرون المذاب في زيت الزيتون جنبًا إلى جنب مع الوصول الحر الى ماء الدكستروز ذي  التركيز 5 ٪ ، (2) مجموعة المركبات (N = 6) ، والتي تم التعامل معها مثل مجموعة PCO ، لكنهم لم يتلقوا إينونثات التستوستيرون، (3) مجموعة التحكم (N = 6) مع الرعاية المنتظمة. تم حقن جميع الحيوانات داخل الصفاق لمدة 14 يومًا. تمت دراسة التعبير عن Irs-2 mRNA باستخدام PCR في الوقت الفعلي وتم الإبلاغ عن تغييرات الطي (FC). تم اعتبار متوسط التعبير في المجموعة الضابطة بمثابة المعيار. تم العثور على حوالي 13.4 ٪ تقليل التعبير في مجموعة PCO (FC = 0.874 ، قيمة P = 0.043). لم يتم العثور على انخفاض كبير في مجموعة المركبات (FC = 0.951 ، قيمة P = 0.076). ومع ذلك ، لم يُظهر تحليل التباين فرقًا معنويًا بين جميع مجموعات الدراسة (قيمة P = 0.085). قد يؤدي النموذج الحالي لـ PCO إلى مقاومة الأنسولين على مستوى الكبد بحجم تأثير منخفض عن طريق تقليل تعبير mRNA عن Irs-2. يُقترح دراسة الجينات والجزيئات المعنية في الأنسجة الأخرى لنماذج حيوانية PCO.There are many animal models for polycystic ovary (PCO); using exogenous testosterone enanthate is one of the methods of induction of these models. However, induction of insulin resistance should also be studied in the modeling technics. Therefore, the present study aims to investigate the expression of insulin receptor substrate (Irs)-2 mRNA in the liver tissue of rat PCO model. Nineteen Wistar rats were divided into three groups; (1) PCO modeling group (N =7) received daily 1.0 mg/100g testosterone enanthate solved in olive oil along with free access dextrose water 5%, (2) vehicle group (N =6), which handled like the PCO group, but did not receive testosterone enanthate, (3) control group (N =6) with standard care. All the animals were administered via intra-peritoneal injection for 14 days. Expression of Irs-2 mRNA was studied with real-time PCR and fold changes (FC) were reported. The average of expression in the control group was considered as the calibrator. About 13.4% expression reduction was found in the PCO group (FC =0.874, P-value =0.043). No significant reduction was found in the vehicle group (FC =0.951, P-value =0.076). However, analysis of variance did not show a significant difference between all the groups of study (P-value =0.085). The present model of PCO might induce insulin resistance at liver level with a low effect size via reduction in the mRNA expression of Irs-2. Study of the involved genes and molecules in other tissues of PCO animal models is suggested