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This paper is aimed at proposing a calculation model for the ground resistance of a grounding scheme servicing a high-voltage direct-current converter station. The method is based on the equivalence of current conduction and electric field from the grounding scheme through the surrounding medium. The grounding scheme is composed of three concentric ring electrodes supported by two horizontal conductors and eight vertical rods. The calculated ground resistance is 4.8 Ω against the experimental value of 5 Ω with an error of 4.2%. The calculated ground resistance value agrees reasonably well with that of 4.7 Ω as obtained using CYMGRD software (version 7.0). The calculated surface-potential values over the ground surface agreed reasonably well with those measured experimentally, with an average deviation not exceeding 6.5%. This study is designed to investigate how ground resistance is decreased by the increase in the scheme parameters, including the rods’ diameter and length, as well as the radius of the inner and outer rings. The dependency of the ground resistance on the soil type is also investigated.

Microclimate parameters (ammonia, ambient temperature, heat index, and relative humidity) surrounding birds affect the production and health status of poultry. Therefore, this study aimed to evaluate the impact of adding natural zeolite to the litter of Japanese quail on improving microclimate parameters and its reflection in growth performance, blood gases, and blood biochemical parameters. A total of 1152 chicks were obtained from the same hatch at the 20th selection generation. Chicks were allocated into two groups based on the litter composition: Group 1: wheat straw as litter (untreated group); Group 2: 80% wheat straw + 20% zeolite (treated group). Each group consisted of 576 chicks: 410 selected line chicks and 166 control line chicks. Significant and favorable effects of the treatment on microclimate parameters during tested periods were found to favor the treated group. Either the treated group or the selected line had significantly better growth performance than the untreated group and control line. Zeolite-treated quails had significantly desirable blood gases and lower blood acidity and serum total iron binding capacity compared to the untreated group. Thus, adding natural zeolite to the litter enhanced the microclimate parameters that improved growth performance, blood gases, and blood biochemical parameters and reduced ammonia emission.

Six new (1, 2, 6, 8, 13, and 20) and twenty previously isolated (3–5, 7, 9–12, 14–19, and 21–26) steroids featuring thirteen different carbocycle motifs were isolated from the organic extract of the soft coral Sinularia polydactyla collected from the Hurghada reef in the Red Sea. The structures and the relative configurations of the isolated natural products have been determined based on extensive analysis of their NMR and MS data. The cytotoxic, anti-inflammatory, anti-angiogenic, and neuroprotective activity of compounds 3–7, 9–12, 14–20, and 22–26, as well as their effect on androgen receptor-regulated transcription was evaluated in vitro in human tumor and non-cancerous cells. Steroids 22 and 23 showed significant cytotoxicity in the low micromolar range against the HeLa and MCF7 cancer cell lines, while migration of endothelial cells was inhibited by compounds 11, 12, 22, and 23 at 20 µM. The results of the androgen receptor (AR) reporter assay showed that compound 11 exhibited the strongest inhibition of AR at 10 µM, while it is noteworthy that steroids 10, 16, and 20 displayed increased inhibition of AR with decreasing concentrations. Additionally, compounds 11 and 23 showed neuroprotective activity on neuron-like SH-SY5Y cells.

Background: Neurocutaneous syndromes (NCS) are a broad term for a group of neurologic disorders that involve the nervous system and the skin. The most common examples are neurofibromatosis type 1 (NF-1) and type 2 (NF-2), tuberous sclerosis (TS), Sturge–Weber syndrome (SWS), ataxia telangiectasia (AT), and Von Hippel Lindau disease (VHL). These disorders are characterized clinically by neurological manifestations such as convulsions, mental retardation and learning disabilities in addition to cutaneous manifestations, and lastly tubers (benign growths found in different organs of the body). Aim of the study: This study aimed to identify clinical, imaging, and neurophysiological profiles of neurocutaneous disorders. Children presented to the Pediatric neurology and Dermatology clinics, Sohag University Hospital who fulfilled the criteria for diagnosis of specific neurocutaneous syndromes were eligible for this study. Patients and methods: All studied patients were subjected to thorough clinical history, full clinical examination, developmental assessment, and dermatological examination. Computed tomography of the brain (CT) and electroencephalography (EEG), ophthalmic, and phoniatric evaluation were also done for all children. Echocardiography was done for only twenty children. Results: During the period of the study we diagnosed 27 cases with neurocutaneous disorders, tuberous sclerosis represented the majority of cases as it was detected in 12 cases (44.45%). The main complaint was convulsions in 19 cases (70.37%), whereas skin pigmentation was detected in 18 cases (66.66%). Developmental assessment showed that global developmental delay was found in 20 cases (74%). CT of the brain showed that 15 cases (55.55%) had intracranial calcifications and abnormal EEG findings were detected in 23 cases (85.2%). 85% of the studied children had various degrees of mental retardation. Echocardiography showed that three cases (15%) had ventricular wall tumor mostly rhabdomyoma. Conclusion: Neurocutaneous disorders had multiple clinical presentations and required a team work approach including various specialties in their evaluation and management.