Evolutionary study on two closed Gammarus (Crustacea, Amphipoda) species from Zagros Mountains (Iran) using molecular methods

Mitochondrial Cytochrome Oxidase Subunit I DNA sequences are a good discriminative marker for phylogenetic studies in crustaceans and especially in amphipoda. In the present study, molecular and morphological data were analyzed to test whether Gammarus lobifer authority and Gammarus balutchi authority which [sic] one or two geographically separated but morphologically similar species. The analyses proved that there are two species and that uplift of the Zagros Mountains was probably the most important cause of Allopatric speciation in this region during the Miocene period

Techno-economical and Environmental Study of Utilizing Alternative Fuel and Waste Heat Reuse in a Cement Plant

In this work, a cement plant was simulated to estimate heat losses and pollution emission in the process. Also, a waste heat recovery system was introduced to use two main sources of heat losses, i.e. flue gas and hot air streams and produce steam and power. Moreover, the use of natural gas as an alternative to the current energy source, fuel oil, was studied in two cases, associated with and without waste heat recovery system. Results showed that 34.28% of initial energy was lost in the base case, 48% of which is from flue gas and hot vent air streams. Also, changing the fuel source from fuel oil to natural gas results in CO2 emission rate to decrease from 118,693 to 115,367 kg/hr, and emission of NO2 and SO2 was reduced to nearly 100%. In addition to environmental benefits, economical analyses suggest the use of waste heat recovery system as well as change of fuel for this plant.Key words: Cement plant; Waste heat recovery; Alternative fuel; HYSYS simulation; Air pollution reductio

Diminished fertility in men with increased BMI

The incidence of obesity as a risk factor for normal life is increasing worldwide. Its impact on hypertension, cardiovascular diseases, osteoporosis, insulin resistance and diabetes mellitus, is well recognized.  Previous studies have proved the association between female obesity and infertility and several linked genes have been worked out. However, a little is known about the effect of obesity on male reproductive system and infertility. Recently some clinical studies have reported diminished semen parameters like sperm count, sperm motility and vitality and changing in reproductive hormones in over weight and obese men. Lack of such study in Asian countries and particularly in Indian population who are genetically more prone to obesity necessitates picking up this research to achieve robust findings in this regard

Sexual Knowledge and Attitudes Among Premarital Couples: A Need for Future Educational Programs

Background: A significant number of youths have insufficient awareness about sexual health; whereas, correct sexual information is the main factor to prevent adverse consequences. Objectives: The current study aimed to investigate the sexual knowledge and attitudes in a sample of Iranian premarital couples. Patients and Methods: In this cross-sectional study, a sequential sample of 500 males and females who met the inclusion criteria was selected. This study was conducted in Kashan, Iran. Participants were in the age range of 16 to 40 years referred for premarital testing and educational classes. Two questionnaires containing demographic data and a culturally based sexual knowledge and attitudes scale were used for data collection. Data were analyzed using the Chi-square test, independent samples t-test, Mann-Whitney U, analysis of variance and multivariate regression. Results: About 50% of premarital couples had poor sexual knowledge and attitudes. The mean score of total sexual knowledge was 12.45 ± 8.54 out of a possible score of 33; and the mean score of total sexual attitudes was 121.63 ± 14.51 out of a possible score of 170. A significant association existed between the score of sexual knowledge and the level of education (P < 0.01), participants’ age (P < 0.01) and the score of sexual attitudes (P < 0.01). Conclusions: The majority of participants had poor sexual knowledge and attitudes regarding different aspects of sexual health

Modeling startup and shutdown transient of the microlinear piezo drive via ANSYS

The article describes the construction-design of the micro linear piezo drive intended for a peripheral cord tensioner in the reflecting surface shape regulator system for large-sized transformable spacecraft antenna reflectors. The research target -the development method of modeling startup and shutdown transient of the micro linear piezo drive. This method is based on application software package ANSYS. The method embraces a detailed description of the calculation stages to determine the operating characteristics of the designed piezo drive. Based on the numerical solutions, the time characteristics of the designed piezo drive are determined

Microlinear piezo drive experiments

The article embraces the experimental description of the micro linear piezo drive intended for the peripheral cord tensioner in the reflecting surface shape regulator system for large-sized transformable spacecraft antenna reflectors. The research target is the experimental investigation of the micro linear piezo drive to determine the stable oscillatory system operating modes which would include improved energy conversion parameters. The following points are briefly presented: test stand construction-design of the peripheral cord tensioner; the determined frequency characteristics and the identified resonant and actual frequencies of an oscillatory system under inertia load. A series of experiments has been conducted for both different preliminary voltages and inertia mass values

GNSS-free outdoor localization techniques for resource-constrained IoT architectures : a literature review

Large-scale deployments of the Internet of Things (IoT) are adopted for performance improvement and cost reduction in several application domains. The four main IoT application domains covered throughout this article are smart cities, smart transportation, smart healthcare, and smart manufacturing. To increase IoT applicability, data generated by the IoT devices need to be time-stamped and spatially contextualized. LPWANs have become an attractive solution for outdoor localization and received significant attention from the research community due to low-power, low-cost, and long-range communication. In addition, its signals can be used for communication and localization simultaneously. There are different proposed localization methods to obtain the IoT relative location. Each category of these proposed methods has pros and cons that make them useful for specific IoT systems. Nevertheless, there are some limitations in proposed localization methods that need to be eliminated to meet the IoT ecosystem needs completely. This has motivated this work and provided the following contributions: (1) definition of the main requirements and limitations of outdoor localization techniques for the IoT ecosystem, (2) description of the most relevant GNSS-free outdoor localization methods with a focus on LPWAN technologies, (3) survey the most relevant methods used within the IoT ecosystem for improving GNSS-free localization accuracy, and (4) discussion covering the open challenges and future directions within the field. Some of the important open issues that have different requirements in different IoT systems include energy consumption, security and privacy, accuracy, and scalability. This paper provides an overview of research works that have been published between 2018 to July 2021 and made available through the Google Scholar database.5311-8814-F0ED | Sara Maria da Cruz Maia de Oliveira PaivaN/

Alignment of distributed oscillation systems in piezo motors

The pressing problem in the space domain is the development of large-sized reflectors for spacecrafts. The specified criteria for reflector structure are precise reflector surface shape and structure mass. Precise reflector surface shape during long-term performance is provided by the alignment of piezoelectric motors used in the reflector structure. These motors exhibit both limited mass-dimensional coefficient and can produce high force. Piezo-motor is distributed mechanical – acoustic oscillation system. In the piezo-motor mechanical – acoustic oscillation is generated by PZT-stack being transferred to the oscillator then to the load action element. The objective of the work is the study the alignment of distributed oscillation systems in piezo-motors. The novelty of the work is using the alignment of oscillator impedance and load impedance to determine the performance resonance frequency of distributed oscillation system in piezo-motor. This method simplifies the possibility of analyzing distributed in piezo-motor oscillation system characteristics. The method was tested under different in piezo-motor load modes

Gaining comprehensive data about sexual knowledge through surveys

Background: Delivery of sexual health services rely on rigorous facts extracted from surveys, but often those facts cannot be available due to the lack of culturally-sensitive questionnaires. Objective: our aim was to show the validity and reliability of the Persian version of the Acquisition of Sexual Information Test (ASIT), a measure selected due to its assemblages with Iranian culture. Materials and Methods: Forward-backward procedure was applied to translate the questionnaire. Cross-sectional study was carried out and psychometric properties of the Iranian version were tested in a thirty sample of reproductive-age women. Face validity was assessed by qualitative and quantitative methods. Content validity was also assessed by calculating two quantitative indicators as content validity index (CVI) and content validity ratio (CVR). Reliability was assessed by test-retest analyses. Results: Impact score was 1.5, the majority of participants (83.3%) stated that the overall level of questionnaire was high but some of the questions were irrelevant to sexual knowledge. Many questions (90%) gained a CVR less than 0.56, and all of them gained CVIs lower than 0.7. Correlation in test-retest reliability was 0.85