On-chip supercontinuum generation in nanostructured Ge11.5As24Se64.5 chalcogenide waveguides using Panda-ring resonator

The on-chip scale microring circuit is proposed to numerically investigate the supercontinuum (SC) generation of light power. The device is formed by the chalcogenide Panda-ring resonator with the nanoscale planar waveguide using Ge11.5As24Se64.5chalcogenide glass channel waveguide, air-clad and MgF2glass for lower cladding. The waveguide is designed to exhibit normal dispersion along with a low-energy pumped at 1.55 μm using a short pulse, which has the duration of 50 fs and peak power ranging from 1 W to 100 W. The numerical result obtained has shown a good-quality SC generation of both the spectral bandwidth and high output peak power. All SC spectral extended to more than 13 μm by cumulative Kerr nonlinearities. The obtained results can be useful for developing new experimental work in the important area of SC generation on compact chip broadband sources, which can be used in both infrared and radio wave applications

Retardation of heat exchanger surfaces mineral fouling by water-based diethylenetriamine pentaacetate-treated CNT nanofluids

Mineral scale deposition on heat exchanging surfaces increases the thermal resistance and reduces the operating service life. The effect is usually intensified at higher temperatures due to the inverse temperature solubility characteristics of some minerals in the cooling water. Scale formation build up when dissolved salt crystallize from solution onto the heated surface, forming an adherent deposit. It is very important for heat transfer applications to cope with the fouling problems in industry. In this present study, a set of fouling experiments was conducted to evaluate the mitigation of calcium carbonate scaling by applying DTPA-treated MWCNT-based water nanofluids on heat exchanger surfaces. Investigation of additive DTPA-treated MWCNT-based water nanofluids (benign to the environment) on fouling rate of deposition was performed. 300 mg L−1 of artificially-hardened calcium carbonate solution was prepared as a fouling solution for deposit analysis. Assessment of the deposition of calcium carbonate on the heat exchanger surface with respect to the inhibition of crystal growth was conducted by Scanning Electron Microscope (SEM). The results showed that the formation of calcium carbonate crystals can be retarded significantly by adding MWCNT-DTPA additives as inhibition in the solution

Educational difference in the prevalence of osteoporosis in postmenopausal women: a study in northern Iran

<p>Abstract</p> <p>Background</p> <p>Osteoporosis is the most common metabolic bone disease in the world and it is rapidly increasing in Iran. In this study the relationship between educational levels and osteoporosis was investigated among Iranian postmenopausal women.</p> <p>Method and subjects</p> <p>Seven hundred and six women aged 50-75 years old were randomly recruited from urban (<it>n </it>= 440) and rural (<it>n </it>= 266) areas in Guilan. Osteoporosis was diagnosed by quantitative ultrasound technique and dual X-ray absorptiometry. Serum 25(OH) D3, body weight and height were measured in all subjects. Other data including age, educational level, menopause age, medications and history of illness were also collected.</p> <p>Results</p> <p>We found that the prevalence of osteoporosis was significantly greater among women with low educational level than women with high educational status (18.0% vs 3.8% <it>P </it>< 0.0001). However, women with low educational level had higher mean serum level of vitamin D than women with high educational level. Osteoporosis was significantly more prevalent among women living in rural areas than women living in urban areas (19.1% v.s 13.3%, <it>P </it>< 0.0001).</p> <p>Conclusion</p> <p>This study showed that educational level is associated with bone health in this population of postmenopausal women with significantly higher osteoporosis found in lower social groups. Therefore, we suggest that women with low social level should be carefully evaluated for signs of osteoporosis during routine physical examinations.</p

Validation of the Iranian version of the Postpartum Specific Anxiety Scale 12-item research short-form for use during global crises (PSAS-IR-RSF-C)

Background Due to its high pervasiveness and adversarial consequences, postpartum anxiety has been one of the most worrying public health concerns in the last decade. According to previous research, the occurrence of mental disorders among women in the postpartum period upsurges significantly in the course of universal disasters. The Postpartum Specific Anxiety Scale – Research Short Form – for use in global Crises [PSAS-IR-RSF-C] has not been used in Iran for postpartum women during a health system shock. Consequently, this study was conducted to determine the validity and reliability of the Persian version (PSAS-IR-RSF-C) during the COVID-19 pandemic.Methods This cross-sectional study was performed with 180 women who were between six weeks and six months after delivery, by random sampling method from December 2021 to June 2022. The validity of the PSAS-RSF-C in terms of face, content, was analyzed, and the construct validity was assessed using exploratory and confirmatory factor analyses. Internal consistency and test–retest reliability of the questionnaire were measured using (Cronbach’s alpha, McDonald’s ω) and intraclass correlation coefficient (ICC), respectively. Results The content validity index and content validity ratio of the Persian version of the PSAS-IR-RSF-C were 0.96 and 0.98, respectively. A three-factor structure was extracted during the exploratory factor analysis process, and model validity was confirmed by the values of fit indices. Cronbach's alpha coefficient, McDonald’s ω and intra-cluster correlation coefficient (95% confidence interval) were 0.74, 0.92 (0.78 to 0.93) and 0.97 (0.93 to 0.98), respectively. Conclusions For the specific assessment of postpartum anxiety among Iranian women during crises, the Persian version of the PSAS-IR-RSF-C is a valid and reliable tool

Psychometric evaluation of the postpartum specific anxiety scale - research short-form among iranian women (PSAS-IR-RSF)

Background The increasing prevalence of postpartum anxiety as a common psychological problem affects a large part of women's lives. Despite the existence of tools in this field, but due to the lack of specificity in reflecting postpartum anxiety, it is necessary to have a specific tool to screen it. Since the psychometric evaluation of the Postpartum Specific Anxiety Scale-Research Short-Form (PSAS-RSF) among Iranian women has not been assessed in Iran until now, so we decided to conduct this study with the aim of psychometric evaluation of the PSAS-IR-RSF.Methods We included 180 women (six weeks to six months postpartum) in the study by random sampling during the period from December 2021 to June 2022. We examined the validity of the PSAS-IR-RSF tool in terms of face, content and construct (through exploratory and confirmatory factor analyses). We used internal consistency and test-retest reliability to determine the reliability of the scale.Results In the present study, content validity index (CVI) and content validity ratio (CVR) of the PSAS-IR-RSF tool were equal to 0.91 and 0.97, respectively. We extracted a four-factor structure through the process of exploratory factor analysis. The values of fitting indices confirmed the validity of the model. Cronbach's alpha coefficient was equal to 0.72 and intra-class correlation coefficient (with 95% confidence interval) was 0.97 (0.98 to 0.93). Conclusions The Persian version of the PSAS-IR-RSF is a valid and reliable tool for the specific evaluation of postpartum anxiety among Iranian women

An integrated approach of multiple correspondences analysis (MCA) and fuzzy AHP method for occupational health and safety performance evaluation in the land cargo transportation

Land cargo transportation is one of the components of the logistics chain with high impact on economic and social development worldwide. However, problems such as top logistics costs, deficiencies in transportation infrastructure and the failure to adopt good operating practices in aspects such as quality, environment, and occupational safety and health affect the ability of companies to comply with the agreements, requirements, and regulations of the clients and other interested parties. One of the most relevant problems for the sector is associated with the high accident rates that make this medium less advantageous compared to other means of transport with impact on operational costs, on logistics indicators, on compliance with legal regulations and customer satisfaction. However, although there are legal standards and management standards in occupational safety and health, evaluating performance can become a difficult and subjective process, due to the complexity of the land cargo transportation and the different interest groups involved. Besides, there is little information in the literature that provides solutions for the industry. Therefore, this document presents an integrated approach between multi-criterion decision making models (MCDM) and the Multiple Correspondences Analysis (MCA) to facilitate the evaluation and improvement of occupational health and safety performance, with a logical process, objective, robust and using both qualitative and quantitative techniques, with real application in the land cargo transportation sector. First, the multivariate method of Multiple Correspondences Analysis (MCA) was used for the evaluation of a sample of companies in the industry, considering the factors and sub-factors identified in the first stage and performing correlational analyzes among the variables. Subsequently, a multicriteria decision-making model was designed to determine the factors and sub-factors that affect occupational health and safety performance through the technique of the Fuzzy Analytic Hierarchy Process (FAHP). Finally, improvement strategies are proposed based on the approaches suggested in this document