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A miniaturized four-port polarization diversity ultra-wide band multiple input multiple output (MIMO) antenna is presented in this article. Different structures are combined and excited with the tapered transmission line to obtain a reduced symmetric layout with the orthogonal arrangement in compact size. An inverted-c-shape partial ground plane is used to decouple the antenna elements placed in close proximity which reduced the overall size and improved the matched impedance of the MIMO antenna. Further, impedance bandwidth is improved by etching the slots in the ground plane. The overall dimension of the proposed compact MIMO antenna is 40 × 40 × 1.524 mm3. The measured characteristics of a fabricated prototype on the FR4 laminate well matched with the simulated results. The antenna exhibits a quasi-omnidirectional radiation pattern on the H-plane throughout the operational bandwidth, with isolation greater than 16 dB, low envelope correlation, and gain variation. this antenna can efficiently be usedfor diversity applications and portable devices. [ABSTRACT FROM AUTHOR]

Introduction: Increasing natural childbirth and decreasing cesarean section is one of the strategies for improving maternal and neonatal health to achieve the millennium development goals. In order to achieve this goal, health transformation plan and program for promotion of natural childbirth have been developed and implemented in Iran. Therefore, this study was performed with aim to analyze the trend of natural childbirth and cesarean section indicators in order to realize the goals of the health transformation plan in Madaen Hospital, Tehran. Methods: In this cross-sectional study, the data of delivery and cesarean section were collected from 2013 to 2017. Changes in the level and trend of natural childbirth and cesarean sections before and after transformation plan were evaluated by independent t-test and regression model of cut-off in STATA software (version 15). Results: The trend of natural childbirth after implementation of the plan increased by 0.685% per month (p=0.020) and the trend of cesarean section decreased by 0.749% per month (p=0.011). In the 3-year period after the health transformation plan, the percentage of natural childbirth increased by 0.680 per month (p

The spinel ferrites MgCrxFe2-xO4 (0.0 ≤ × ≥ 1.0) were prepared through the solid state reaction using conventional ceramic method at 1300°C in air. The homogeneous phase of the ferrite samples was observed from the X-ray diffraction study. Lattice parameter of the samples was found to decrease with increasing Cr concentration in the system obeying Vegard's law. The ac electrical resistivity, measured as a function of temperature, decreases with the increase of temperature indicating the semiconducting nature of all the samples. The activation energies were calculated and found to decrease with increasing Cr content. The lower activation energies are associated with higher electrical conductivity. With the increase of temperature, dielectric constant (ε') and dielectric loss tangent are observed to be increased; while with the increase of frequency, dielectric constant (ε') and dielectric loss tangent decrease for all the samples. [ABSTRACT FROM AUTHOR]

In this paper, the critical parameters of a method of welding with shielding gas arc welding (GMAW) are discussed; this method is an important process in creating high quality metal permanent connections in various industries, including the automobile industry to improve the quality of stem diameter welding parameters. One of the most useful techniques for modeling and solving the problems is Response Surface Method. In this paper, considering five most important factors such as speed welder, torch angle with the work piece, electrode diameter, wire speed, gas consumption ,and CO2 levels as input variables, can be controlled independently from the level of response, the relationship between the input variables and the response variables were determined using linear regression. Then optimum value for each factor was calculated using non-linear programming model to evaluate the results obtained along with the comparison of output of the Simulation Annealing Algorithm. In this study, both qualitative and quantitative variables are considered to evaluate and optimize all response variables regarding that these variables are not the same, and then fuzzy set theory and LP metric are used to find answers for multi-objective optimization methods.

Abstract: To compensate for bismuth loss that occurred during the film deposition process, Bi1.5Zn1.0Nb1.5O7 (BZN) thin films were deposited at room temperature from the ceramic targets containing various excess amounts of bismuth (0–20mol%) on Pt/TiO2/SiO2/Si substrates by using RF magnetron sputtering technique. The effect of bismuth excess content on the microstructure and electrical properties of BZN thin films was studied. The microstructure and chemical states of the thin films were studied by SEM and XPS. EPMA was employed to assess the film stoichiometry. The X-ray diffraction analysis reveals that the BZN thin films exhibit the amorphous structure in nature. An appropriate amount of excess bismuth improves the dielectric and electrical properties of BZN thin films, while too much excess bismuth leads to deterioration of the properties. BZN thin film with 5mol% excess bismuth exhibits a dielectric constant of 61 with a loss of 0.4% at 10kHz and leakage current of 7.26×10−7 A/cm2 at an electric field of 200kV/cm. [Copyright &y& Elsevier]

Due to its heavy reliance on fossil fuels and rapid urbanization, China's economic growth is accompanied by environmental problems. Hence, it is vital to solve the issue by promoting green growth and finding factors to boost it. The current study presents FinTech as a factor enhancing green growth in China through the mediation effect of the energy transition. The green growth index is created through a comprehensive literature review and selecting the most critical indicators. It has been established through benchmark regression that FinTech positively affects green growth in China. However, results also prove that the energy transition is the path through which FinTech affects green growth. Policymakers are advised to direct their efforts toward the energy transition and FinTech to solve the problems related to China's rapid economic growth., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

Background: Food handlers have been found to play essential roles in transmitting foodborne diseases and can pose a significant public health problem. Our study aimed to assess the knowledge, attitude, and practices (KAP) of food safety measures among the rural households of Bangladesh., Materials and Methods: We conducted this community-based cross-sectional study among women above 18 years involved with food preparation in rural households of four villages in Bangladesh. A total of 400 respondents were selected using the multistage cluster sampling technique. Data were collected using pretested and predesigned questionnaires based on the World Health Organization's (WHO) five keys for food safety. We used Stata (Version 16) for all statistical analyses., Results: The mean age of the participants was 42.09 ± 12.96 years. The median KAP scores [interquartile range (IQR)] were 7 (21-10), 16 (5-18), and 26 (9-30), respectively. We found the median KAP scores were significantly lower in the age group >55 years than in age groups of 18-25, 26-35, 36-45, and 46-55 years ( P < 0.05 for all). In addition, the median KAP scores were significantly higher in respondents who were married, literate, employed/active, living in pakka/semipakka house, and with a monthly family income of >5,000 BDT ( P < 0.05 for all). Among all, 33.75%, 80.25%, and 69.00% had good (≥80% of total) KAP scores, respectively. Multivariable regression analysis revealed that monthly family income >5,000 BDT was a significant predictor of good knowledge [Adjusted Odds Ratio (aOR): 3.51, 95%CI: 1.55-7.98], good attitude (aOR: 5.82, 95%CI: 2.80-11.70), and good practice (aOR: 3.18, 95%CI: 1.67-6.07). Age >55 years was a significant predictor of good attitude (aOR: 0.38, 95%CI: 0.17-0.81) and good practice (aOR: 0.48, 95%CI: 0.21-0.89). Having ≤4 members in the family was a significant predictor of good practice (aOR: 1.85, 95%CI: 1.13-3.03) regarding food safety measures., Conclusion: The study found that KAP among rural Bangladeshi women regarding food safety were relatively satisfactory. However, having a poor monthly income and living in a large family were impediments to good food-safety practices where work can be done. The findings of this study may help develop health intervention programs for food handlers to further improve KAP toward food safety, thereby reducing foodborne illness in households., Competing Interests: The authors declare no conflicts of interest for this work., (Copyright © 2022 Mst. Rokshana Rabeya et al.)

Fifth generation (5G) communication systems deploy a massive MIMO technique to enhance gain and spatial multiplexing in arrays of 16 to 128 antennas. In these arrays, it is critical to isolate the adjacent antennas to prevent unwanted interaction between them. Fifth generation absorbers, in this regard, are the recent interest of many researchers nowadays. The authors present a dual-band novel metamaterial-based 5G absorber. The absorber operates at 24 GHz and 28 GHz and is composed of symmetric meander lines connected through a transmission line. An analytical model used to calculate the total number of required meander lines to design the absorber is delineated. The analytical model is based on the total inductance offered by the meander line structure in an impedance-matched electronic circuit. The proposed absorber works on the principal of resonance and absorbs two 5G bands (24 GHz and 28 GHz). A complete angular stability analysis was carried out prior to experiments for both transverse electric (TE) and transverse magnetic (TM) polarizations. Further, the resonance conditions are altered by changing the substrate thickness and incidence angle of the incident fields to demonstrate the functionality of the absorber. The comparison between simulated and measured results shows that such an absorber would be a strong candidate for the absorption in millimetre-wave array antennas, where elements are placed in proximity within compact 5G devices.

A knowledge, attitude and practice survey of acquired Immune Deficiency Syndrome (AIDS) was conducted among 805 paramedics at a tertiary care hospital in Islamabad in mid 1993. The mean age of the study population was 29.0 +/- 7.2 years and 59% were males. Almost 25% individuals either had no or upto primary level education. Initial response of 10% subjects was not having heard of AIDS and 70% thought their knowledge was sketchy, while 43% could not mention any cause for the disease. Almost 50% did not know that HIV infection could be asymptomatic. With respect to attitudes about AIDS, 30% subjects thought that changing life style shall have no effect on avoiding AIDS, 50% were of the view that at present AIDS did not pose a significant threat to them and 4% individuals however, admitted to having risk of contracting the disease. There existed significant gaps in the knowledge and attitudes of paramedical staff about AIDS and correlated with the level of education of the staff. These deficiencies need to be addressed through developing health education packages in local languages, targeted especially towards paramedical staff.