High-efficiency electromagnetic energy harvesting using double-elliptical metasurface resonators.

This study introduces a metasurface (MS) based electrically small resonator for ambient electromagnetic (EM) energy harvesting. It is an array of novel resonators comprising double-elliptical cylinders. The harvester's input impedance is designed to match free space, allowing incident EM power to be efficiently absorbed and then maximally channelled to a single load through optimally positioned vias. Unlike the previous research works where each array resonator was connected to a single load, in this work, the received power by all array resonators is channelled to a single load maximizing the power efficiency. The performance of the MS unit cell, when treated as an infinite structure, is examined concerning its absorption and harvesting efficiency. The numerical results demonstrate that the MS unit cell can absorb EM power, with near-perfect absorption of 90% in the frequency range of 5.14 GHz to 5.5 GHz under normal incidence and with a fractional bandwidth of 21%. The MS unit cell also achieves higher harvesting efficiency at various incident angles up to 60o. The design and analysis of an array of 4x4 double elliptical cylinder MS resonators integrated with a corporate feed network are also presented. The corporate feed network connects all the array elements to a single load, maximizing harvesting efficiency. The simulation and measurement results reveal an overall radiation to AC efficiency of about 90%, making it a prime candidate for energy harvesting applications.

Dual-Band, Wide-Angle, and High-Capture Efficiency Metasurface for Electromagnetic Energy Harvesting.

A dual-band metasurface (MS) with a wide reception angle operating at Wi-Fi bands (2.4 GHz and 5.4 GHz) is presented for electromagnetic (EM) energy harvesting applications. The MS unit cell comprises a subwavelength circular split ring resonator printed on the low-loss substrate. An air layer is sandwiched between two low-loss substrates to enhance the harvesting efficiency at operating frequencies. One of the main advantages of the proposed MS is that it uses only one harvesting port (via) to channel the captured power to the optimized load (50 Ω), which simplifies the design of a combined power network. According to the results of full-wave EM simulations, the proposed MS has a near-unity efficiency of 97% and 94% at 2.4 GHz and 5.4 GHz, respectively, for capturing the power of incident EM waves with normal incidence. Furthermore, the proposed MS harvester achieves good performance at up to 60° oblique incidence. To validate simulations, the MS harvester with 5 × 5-unit cells is fabricated and tested, and its EM properties are measured, showing good agreement with the simulation results. Because of its high efficiency, the proposed MS harvester is suitable for use in various microwave applications, such as energy harvesting and wireless power transfer.

Enterobiasis among Yemeni children: a cross-sectional study.

Enterobiasis is a highly infectious parasitic disease spreading worldwide including Yemen. Therefore, this study aimed to investigate the prevalence and risk factors of enterobiasis among Yemeni children in Dhamar governorate. A total of 402 children (aged 1-12 years) participated in this cross-sectional survey carried out at Thamar University Al-Wahdah Teaching Hospital (TUWTH), between 2018 and 2019. Enterobius vermicularis infection was examined using the adhesive tape technique. Association between risk factors and enterobiasis were measured by prevalence ratio (PR). The overall prevalence of enterobiasis was found to be 29.4% (118/402). Risk factors that showed independent association with the infection were child's care responsibility (PR = 1.90; 95% CI = 1.37-2.63; P = 0.001); irregular washing hands before meals (PR = 2.01; 95% CI = 1.32-3.05; P = 0.003); habit of nail biting or cutting by teeth (PR = 1.61; 95% CI = 1.18-2.21; P = 0.002); habit of putting toys or pen in mouth (PR = 1.58; 95% CI = 1.19-2.10; P = 0.002); frequent anal itching (PR = 1.46; 95% CI = 1.10-1.93; P = 0.016); using anthelmintic during the last six months (PR = 1.68; 95% CI = 1.20-2.36; P = 0.011); and parents have no knowledge on preventive measures (PR = 1.62; 95% CI = 1.04-2.53; P = 0.036). Prevalence of enterobiasis among Yemeni children in Dhamar governorate is high with higher infection rate among those aged 1-6 years. Health education and mass treatment are highly recommended among this poor population.

Changes in Serum Protein and Enzyme Levels in Human T Lymphotropic Virus-1-Infected Patient.

This study aims to evaluate the changes in serum protein levels in a patient with confirmed human T lymphotropic virus type-1 (HTLV-1) infection. Screening and confirmation tests were performed for HTLV-1, along with an assessment of overall albumin, alpha 1 and 2, and gamma and beta globulin levels, using SAS-3 protein electrophoretic analysis. HTLV-1 positivity was confirmed with enzyme-linked immunosorbent assay (ELISA) and nucleic acid amplification testing (NAT). The biochemical tests or protein levels did not exhibit any changes in HTLV-1 infection, indicating that HTLV-1 results in a rare silent infection that does not result in changes in protein levels at the early stages. To aid early detection of the virus and initiate treatment, a comprehensive investigation at the protein and gene levels should be performed. Key Words: HTLV-1, Serum proteins, SAS-3 electrophoretic analysis.

Relationship Between White Matter Integrity and Plasma Leptin Levels in Drug-Naïve and Medicated Patients With Major Depressive Disorder.

Many previous studies have noticed obvious alterations in different white matter tracts among patients with major depressive disorder (MDD). Growing evidence also strongly suggest a role of leptin in the pathogenesis of MDD, but with conflicting results of leptin levels. However, no previous studies have examined the relationship between leptin and white matter integrity of patients with MDD. Therefore, we aimed in this study to investigate the relationship between white matter alterations and plasma leptin levels in both drug-naïve and medicated MDD patients. We measured plasma leptin levels and white matter integrity using diffusion tensor imaging (DTI) and voxel-based analysis (VBA) in 140 participants (40 drug-naïve MDD patients; 40 medicated MDD patients; 60 healthy controls) aged between 18 and 49 years old. A significant reduced fractional anisotropy (FA) value in the dorsomedial thalamus was found for both drug-naïve and medicated MDD patients compared to the healthy non-depressed participants (p < 0.01, corrected). In addition, leptin levels were significantly higher in the drug-naïve MDD patients and were negatively correlated with the detected white matter alteration. Our results suggest that the elevated plasma leptin levels in the drug-naïve MDD group might be associated with the changes of the white matter integrity in the dorsomedial thalamus region.

Effect of testosterone boosters on body functions: Case report.

Testosterone boosters are supplementary substances that can be used for the purpose of increasing testosterone levels in the blood. This study aimed to evaluate the side effects and health risks of testosterone boosters among athletes. A sportsman came to the King Saud Hospital, Unaizah, Qassim, Saudi Arabia, suffering from abdominal pain. The attending doctor requested general laboratory tests. He admitted to having consumed two courses of a testosterone booster over a period of 42 days following the instructions of the manufacturer. In total, the athlete in question consumed several courses, twice before the abdominal pain started and twice after it subsided. The blood tests and reports suggested that the commercial product consumed might negatively affect several hepatic functions and resulted in slightly increased testosterone concentrations after the fourth course. In conclusion, administration of testosterone booster products, although obtained from trusted sources, may still present some health risks. Further studies with large sample size and for a long period need to be done to confirm the current findings.

Proteomic Profile of Lymphoid Leukemia.

Lymphoid (or lymphocytic/lymphoblastic) leukemia, one of two major types of leukemias (lymphoid and myeloid), is divided into two subtypes, acute lymphoid leukemia (ALL) and chronic lymphocytic leukemia (CLL), depending on the maturation stage and speed of multiplication of the bone marrow lymphocytes. Early diagnosis and treatment can make the difference between life and death. Advancements in the field of proteomics may allow the development of early biomarkers and more effective agents to combat both these types of cancer, and to better understand the underlying mechanisms of the disease. The aim of this review was to elucidate the pathophysiology of lymphocytic leukemia using cancer proteomics techniques from 2007 until 2017. Only relevant original research articles archived in the Science Direct, PubMed and/or the Google Scholar databases within this period were included, which were a total of 30 studies. The role of proteomes in the detection, diagnosis and treatment of ALL and CLL was examined separately. Overall, the findings of this study confirm the viability of proteome analysis in profiling lymphocytic leukemia; and highlight novel leukemia biomarkers and potential therapeutic targets.

Quality of life in patients with vitiligo: an analysis of the dermatology life quality index outcome over the past two decades.

Vitiligo is one of the most important skin disorders that does not cause much physical impairment, but due to its disfiguring appearance, patients have disturbances in mental health and quality of life (QoL). The dermatology life quality index (DLQI), as one of the most specific QoL instruments, is now used widely for patients with vitiligo. The main objective of this review is to collect and present detailed information about issues and disturbances related to the QoL of patients with vitiligo by reviewing the DLQI studies worldwide in the past 20 years. The impact of vitiligo assessed by the DLQI varies according to the clinical and demographic characteristics of patients. In the majority of our reviewed studies, women showed more QoL impairment than men did, as did young patients compared to elderly ones, married women with vitiligo than singles, and patients with involvement on exposed sites than those on unexposed sites. Dark-skinned people showed more life quality effects than white people did. Dermatologists should pay particular attention to such patients who experience insufficient QoL, as they require more effort to cure their disease.

Hidden victims of childhood vitiligo: impact on parents' mental health and quality of life.

This study aims to assess the impact of childhood vitiligo on the psychological status and quality of life of their parents, and to determine how this varies according to their children's disease condition. The study included 50 families of children with vitiligo (a total of 75 participants) and 50 families of normal children (a total of 79 participants). The psychosocial impact of the disease on parents was measured using the Self-rated Health Measurement Scale (SRHMS) and the Dermatitis Family Impact Questionnaire (DFI). SRHMS scores for parents of children with vitiligo were significantly lower than for parents with normal children. In addition, women had lower scores than men in the study group. The mean DFI score in affected families was higher than in unaffected families. Parents of children with vitiligo have significant psychological problems, and their quality of life is poorer than for parents of normal children. In conclusion, parents of children with vitiligo need as much care and attention as their affected children.