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In this paper, the free vibration behavior of isotropic and orthotropic cylindrical shell panels with variable curvature subjected to certain ends boundary conditions is analyzed by the transfer matrix technique and solved by the Romberg integration approach. Flügge's shell theory is employed to model the governing three-dimensional equations of vibration and Fourier's approach is used to deform the displacement fields as trigonometric functions in the longitudinal direction. As a result of a semi-analytical procedure is conducted, the coupled governing equations of panel problem can be written in a matrix partial differential equation of first order with variable coefficients and reduced from the two-dimensional problem to one-dimensional one which is solved numerically as an initial-value problem. The proposed model is applied to get the natural frequencies and mode shapes for the vibration behavior of two-side simply-supported cylindrical panels with simply-supported, free-free, clamped-free and clamped-clamped ends boundary conditions lying at their curved edges. The sensitivity of the vibration behavior to the variety of curvature, panel parameters and material orthotropy of shell is studied. [ABSTRACT FROM AUTHOR]

Hydatid cysts of Echinococcus granulosus were recovered from 27.59% (149/540) of camels Camelus dromedarius from a slaughterhouse in Cairo. The organ distribution of cysts was 57=38.26% in the lung, 65=43.62 % in the liver, 23=15.44 % in both liver and lungs, and 4=2.68% in the other organs such as the brain, tongue, and spleen, etc. The investigation looked at how four compounds from scorpions: chitosan, chitosan nanoparticles (Cs-NPs), venom as well as venom-loaded chitosan nanoparticles (V-CN) affect against in vitro hydatid cyst protoscoleces. Aseptically, cyst fluid protoscoleces were aspirated. Each of the aforementioned compounds was always examined in triplicates at doses of 20, 50, and 100 µg/ml for incubation periods of 30, 60, 120, and 240 min to show its scolicidal effects. Using the 0.1% eosin test, the viability of protoscoleces was determined. According to the degree of deacetylation (DDA), concentration, exposure period, and size, all compounds demonstrated statistically significant differences (P > 0.05) against the protoscoleces activity. Chitosan and chitosan nanoparticles had a scolicidal action, directly related to DDA and inversely proportional to size. The most effective scolicidal compound was venom-loaded chitosan nanoparticles, which destroyed all protoscoleces at a concentration of 100 µg/ml, after 240 min of incubation. [ABSTRACT FROM AUTHOR]

Aim: This investigation aims to extract chitin and chitosan from the three scorpions: Leiurus quinquestriatus (LQ), Androctonus crassicauda (AC) and Androctonus amoreuxi (AA) for the first time and to determine the loading capacity and efficiency of LQ venom-loaded chitosan nanoparticles (V-CN). Methods: chitin was extracted and converted to chitosan which is converted to nanoparticles (Cs-NPs) by ball-milling technique. LQ venom was collected, characterized, and loaded on Cs-NPs via the ionic gelation method. Different techniques were used to characterize the obtained compounds. Results: the dried powder of LQ, AC, and AA contained 19.7 %, 15.4 %, and 15 % chitin, respectively. FT-IR confirmed the successful preparation of chitin, chitosan, and V-CN samples. Loading capacity reached 76.50 %, while encapsulation efficiency reached 87.98 %. Conclusion: scorpion venom was effectively loaded on chitosan samples. Its physical and compound qualities, specifically, were viewed as great for biomedical and drug applications. [ABSTRACT FROM AUTHOR]

A rare anomaly of telson vesicle with two functional aculei is observed and discussed in a Parabuthus liosoma (Ehrenberg, 1828) specimen collected from Jizan, Saudi Arabia. [ABSTRACT FROM AUTHOR]

Drylands correspond to ca. 40% of the world's land surface. Because of their ecological importance, these areas are regularly considered for agricultural purposes. Scorpion assemblages often exhibit higher levels of species diversity in dry habitats and are beneficial indicators in ecological studies in such environments. In this study, we investigated the effects of climatic and spatial predictors on beta diversity patterns among scorpion assemblages distributed in the drylands of Egypt. Scorpion occurrences were compiled from the scientific literature. For each location, we created a set of climatic variables related to precipitation, temperature, and solar irradiation, as well as spatial predictors. A total of 134 scorpion occurrences were obtained, comprising 21 species grouped into three families. Climatic and spatial variables together influenced the patterns of scorpion diversity in Egyptian landscapes. Species replacement accounted for 69% of the total beta diversity. In addition, species replacement was positively affected by climatic and spatial variables. Our results suggest a reciprocal link between the region's ecological history and the patterns of beta diversity observed in scorpion assemblages from Egyptian drylands. [ABSTRACT FROM AUTHOR]

We describe and illustrate a new scorpion species, Androctonus tihamicus sp. nov., from the Mecca Province of southwestern Saudi Arabia. The new species is compared to the genus Androctonus Ehrenberg, 1828, which is distributed throughout the Middle East, and especially to A. australis (Linnaeus, 1758). We provide the molecular phylogeny for this species. [ABSTRACT FROM AUTHOR]

A new species, Leiurus hadb Al-Qahtni, Al-Salem, Alqahtani & Badry, sp. nov., is described and illustrated from the Majami al-Hadb Protected Area in the Riyadh Province of Saudi Arabia. The new species is compared with species of Leiurus distributed in Saudi Arabia, especially L. arabicus Lowe, Yağmur & Kovařík, 2014. The integrated results indicate that the population found in Majami al-Hadb represents a distinct species, which is described herein. Moreover, the molecular analysis is conducted on the mitochondrial gene 16S rRNA to compare L. hadb sp. nov. with samples of L. arabicus and L. haenggii from Saudi Arabia. The analysis revealed a genetic divergence ranging from 6.0 to 12%. The combination of molecular evidence and morphological characteristics provides adequate support for recognizing the Majami al-Hadb population as a distinct species. Additionally, an identification key for the genus Leiurus found in Saudi Arabia is also provided. [ABSTRACT FROM AUTHOR]

Background: Although swallowing disorders can impact individuals of any age, some are unique to the elderly, and others are frequent. Some disorders, such as achalasia, are diagnosed by esophageal manometry studies, which assess lower esophageal sphincter (LES) pressure and relaxation, peristalsis in the esophageal body, and contraction wave characteristics. This research aimed to evaluate esophageal motility dysfunction in symptomatic patients and its relation to age. Methods: Conventional esophageal manometry was performed on 385 symptomatic patients who were divided into two groups; Group A (age < 65 years old) and Group B (age ≥ 65 years). The geriatric assessment for Group B included cognitive, functional, and clinical frailty scales (CFS). Additionally, a nutritional assessment was done for all patients. Results: About one-third of the patients (33%) had achalasia, in which manometric results were significantly higher in Group B (43.4%) than in Group A (28.7%) (P = 0.016). The resting lower esophageal sphincter (LES) pressure, as determined by manometry examination, was significantly lower in Group A than in Group B. In contrast, complete LES relaxation percentage and normal esophageal body peristalsis were significantly higher in Group A than in Group B. Patients who exhibited evidence of achalasia in the manometric study had a significantly increased risk of established malnutrition and functional impairment. Conclusions: Achalasia is a prevalent cause of dysphagia in elderly patients, placing them at risk of malnutrition and functional impairment. Thus, a multidisciplinary approach is vital when providing care for this population. [ABSTRACT FROM AUTHOR]

The monotypic genus Buthiscus was described by Birula (1905) with the species Buthiscus bicalcaratus from the Sahara Desert of southern Tunisia. Until now, huge gaps exist in the knowledge of this species which is classified as endemic to North Africa. This paper aims to enrich the existing knowledge on this poorly known species with redescribing specimens of both sexes collected from Libya using widely illustrated redescription, in light of modern standards ruling the taxonomy of scorpions. [ABSTRACT FROM AUTHOR]