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This paper presents a new method for determining the effect of healthy personal protective material (HPPM) stripes, such as surgical masks, protective suits, and overhead and foot covers, on the durability and physicomechanical characteristics of concrete for use in architectural forms. Because of the current global epidemic caused by coronavirus (COVID-19), the use of HPPM, such as surgical masks, protective suits, and overhead and foot covers, has increased considerably. COVID-19's second and third waves are currently affecting various countries, necessitating the use of facemasks (FM). Consequently, millions of single FM have been discharged into the wild, washing up on beaches, floating beneath the seas, and ending up in hazardous locations. The effect of stripe fibers on the physicomechanical characteristics of concrete, such as the workability, Uniaxial Compressive Strength UCS, flexural strength, impact strength, spalling resistance, abrasion resistance, sorptivity, Water absorption Sw, porosity (ηe), water penetration, permeability, and economic and eco-friendly aspects, need to be determined. With a focus on HPPM, especially single-use facemasks, this study investigated an innovative way to incorporate pandemic waste into concrete structures. Scanning electron microscope and X-ray diffraction patterns were employed to analyze the microstructures and interfacial transition zones and to identify the elemental composition. The HPPM had a pore-blocking effect, which reduced the permeability and capillary porosity. Additionally, the best concentrations of HPPM, particularly of masks, were applied by volume at 0, 1, 1.5, 2.0, and 2.5%. The use of mixed fibers from different HPPMs increased the strength and overall performance of concrete samples. The tendency of growing strength began to disappear at approximately 2%. The results of this investigation showed that the stripe content had no effect on the compressive strength. However, the stripe is critical for determining the flexural strength of concrete. The UCS increased steadily between 1 and 1.5% before falling marginally at 2.5%, which indicates that incorporating HPPM into concrete had a significant impact on the UCS of the mixture. The addition of HPPM to the mixtures considerably modified the failure mode of concrete from brittle to ductile. Water absorption in hardened concrete is reduced when HPPM stripes and fibers were added separately in low-volume fractions to the concrete mixture. The concrete containing 2% HPPM fibers had the lowest water absorption and porosity percentage. The HPPM fibers were found to act as bridges across cracks, enhancing the transfer capability of the matrices. From a technological and environmental standpoint, this study found that using HPPM fibers in the production of concrete is viable., (© 2023. The Author(s).)

The rapid development and mutations have heightened ceramic industrialization to supply the countries' requirements worldwide. Therefore, the continuous exploration for new reserves of possible ceramic-raw materials is needed to overwhelm the increased demand for ceramic industries. In this study, the suitability assessment of potential applications for Upper Cretaceous (Santonian) clay deposits at Abu Zenima area, as raw materials in ceramic industries, was extensively performed. Remote sensing data were employed to map the Kaolinite-bearing formation as well as determine the additional occurrences of clay reserves in the studied area. In this context, ten representative clayey materials from the Matulla Formation were sampled and examined for their mineralogical, geochemical, morphological, physical, thermal, and plasticity characteristics. The mineralogical and chemical compositions of starting clay materials were examined. The physicochemical surface properties of the studied clay were studied utilizing SEM-EDX and TEM. The particle-size analysis confirmed the adequate characteristics of samples for white ceramic stoneware and ceramic tiles manufacturing. The technological and suitability properties of investigated clay deposits proved the industrial appropriateness of Abu Zenima clay as a potential ceramic raw material for various ceramic products. The existence of high kaolin reserves in the studied area with reasonable quality and quantity has regional significance. It would significantly help reduce the manufacturing cost and overwhelm the high consumption rate. The ceramic manufacturers in the investigated areas are expected to bring steady producers into the industry in the long term to gain the advantage of low-cost raw materials, labor, and factory construction., (© 2023. The Author(s).)

Biomimicry strategies, inspired from natural organization of living organisms, are being widely used in the design of nanobiomaterials. Particularly, nonlithographic techniques have shown immense potential in the facile fabrication of nanostructured surfaces at large-scale production. Orthopedic biomaterials or coatings possessing extracellular matrix-like nanoscale features induce desirable interactions between the bone tissue and implant surface, also known as osseointegration. In this study, nanopillared chitosan/gelatin (C/G) films were fabricated using nanoporous anodic alumina molds, and their antibacterial properties as well as osteogenesis potential were analyzed by comparing to the flat C/G films and tissue culture polystyrene as controls. In vitro analysis of the expression of RUNX2, osteopontion, and osteocalcin genes for mesenchymal stem cells as well as osteoblast-like Saos-2 cells was found to be increased for the cells grown on nano C/G films, indicating early-stage osteogenic differentiation. Moreover, the mineralization tests (quantitative calcium analysis and alizarin red staining) showed that nanotopography significantly enhanced the mineralization capacity of both cell lines. This work may provide a new perspective of biomimetic surface topography fabrication for orthopedic implant coatings with superior osteogenic differentiation capacity and fast bone regeneration potential.

As one of the leading causes of central vision loss in elderly population, worldwide cases of age-related macular degeneration (AMD) have seen a dramatic increase over the past several years. Treatment regimens for AMD, especially with biological agents, are complicated due to anatomical and physiological barriers, as well as administration of high doses and frequent regimens. Some clinical examples include monthly intravitreal administration of anti-VEGF antibody ranibizumab (Lucentis®) from Genentech and aflibercept (Eylea®) from Regeneron Pharmaceuticals. Long-acting sustained intraocular drug delivery provides promising solutions, such as Vitrasert® from Bausch & Lomb, an intravitreal biodegradable polymeric implant made from poly(D,L-lactic co glycolic acid) (PLGA), and can be used as a guiding reference to formulate sustained delivery systems. In this review, we discuss the anatomy and physiology of the eye, barriers to delivery, pathology of AMD, opportunities for biological therapeutics, and future prospects of intraocular delivery strategies that are in development for treatment of AMD., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Purpose: To evaluate the perspective of ophthalmology residents in the US about their residency programs and compare the competency of residency programs to international competency levels set by the International Council of Ophthalmology (ICO)., Methods: A cross-sectional web-based survey extracted from the ICO published competency standards was sent to program directors of ophthalmology residency programs in the US to forward it to current PGY-3, 4 residents, and residency graduates from 2011 to 2014., Results: Eighty-seven responses were received, comprising 61 residents and 26 graduates. Most respondents were highly satisfied with their programs (93.6%). Clinic-based training was rated satisfactorily. Insufficient exposure to low-vision rehabilitation (38.5%), refraction and contact lenses prescription (38.5%), and vitreo-retinal surgeries (38.5%) was reported. Respondents were satisfied with their overall surgical experiences, with the vast majority (>83%) rating case volume, complexity, and variety as satisfactory or better. A significant group stated they had insufficient exposure to extra-capsular cataract extraction (26.3%), refractive surgery (19.7%), and orbital surgery (64.5%). All graduates surveyed passed their Ophthalmic Knowledge Assessment Program (OKAP) examinations, and 72% felt their residency programs adequately prepared them for the examinations. All respondents reported insufficient training in certain nonclinical areas, such as practice management, staffing, and administration skills., Conclusions: Ophthalmology residents in the US express high levels of satisfaction with their residency training programs. While most programs adequately address most ICO core objectives, certain curriculum modifications should be considered.

Objectives: To assess the prevalence of awareness and use of massive open online courses (MOOCs) among medical undergraduates in Egypt as a developing country, as well as identifying the limitations and satisfaction of using these courses., Design: A multicentre, cross-sectional study using a web-based, pilot-tested and self-administered questionnaire., Settings: Ten out of 19 randomly selected medical schools in Egypt., Participants: 2700 undergraduate medical students were randomly selected, with an equal allocation of participants in each university and each study year., Primary and Secondary Outcome Measures: Primary outcome measures were the percentages of students who knew about MOOCs, students who enrolled and students who obtained a certificate. Secondary outcome measures included the limitations and satisfaction of using MOOCs through five-point Likert scale questions., Results: Of 2527 eligible students, 2106 completed the questionnaire (response rate 83.3%). Of these students, 456 (21.7%) knew the term MOOCs or websites providing these courses. Out of the latter, 136 (29.8%) students had enrolled in at least one course, but only 25 (18.4%) had completed courses earning certificates. Clinical year students showed significantly higher rates of knowledge (p=0.009) and enrolment (p<0.001) than academic year students. The primary reasons for the failure of completion of courses included lack of time (105; 77.2%) and slow Internet speed (73; 53.7%). Regarding the 25 students who completed courses, 21 (84%) were satisfied with the overall experience. However, there was less satisfaction regarding student-instructor (8; 32%) and student-student (5; 20%) interactions., Conclusions: About one-fifth of Egyptian medical undergraduates have heard about MOOCs with only about 6.5% actively enrolled in courses. Students who actively participated showed a positive attitude towards the experience, but better time-management skills and faster Internet connection speeds are required. Further studies are needed to survey the enrolled students for a better understanding of their experience., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Aim: To develop and test an Arabic version of the National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25)., Methods: NEI-VFQ-25 was translated into Arabic according to WHO translation guidelines. We enrolled adult consenting patients with bilateral chronic eye diseases who presented to 14 hospitals across Egypt from October to December 2012, and documented their clinical findings. Psychometric properties were then tested using STATA., Results: We recruited 379 patients, whose mean age was (54.5±15)y. Of 46.2% were males, 227 had cataract, 31 had glaucoma, 23 had retinal detachment, 37 had diabetic retinopathy, and 61 had miscellaneous visual defects. Non-response rate and the floor and ceiling numbers of the Arabic version (ARB-VFQ-25) were calculated. Internal consistency was high in all subscales (except general health), with Cronbach-α ranging from 0.702-0.911. Test-retest reliability was high (intraclass correlation coefficient 0.79)., Conclusion: ARB-VFQ-25 is a reliable and valid tool for assessing visual functions of Arabic speaking patients. However, some questions had high non-response rates and should be substituted by available alternatives. Our results support the importance of including self-reported visual functions as part of routine ophthalmologic examination.