Perceptions of clinical dental students toward online education during the COVID-19 crisis: An Egyptian multicenter cross-sectional survey

Objectives: To evaluate the perceptions of clinical dental students on the role of online education in providing dental education during the COVID-19 crisis. Materials and Methods: A cross-sectional online survey was sent to four Egyptian dental schools from the 20th of January 2021 to the 3rd of February 2021. Survey questions included the demographics, uses, experiences, perceived benefits, and barriers of distance learning in dentistry during the COVID-19 pandemic. Responses were collected from the clinical dental school students. Categorical data were presented as frequencies (n) and percentages (%) and were analyzed using Fisher’s exact test. Results: Three hundred thirty-seven clinical dental students across four Egyptian dental schools responded. Most students used either Google Classroom or Microsoft Teams to access the online content. The data showed that the COVID-19 pandemic affected the academic performance of most participants (97.4%) with varying degrees. On average, students were neutral when asked to rate the online lectures, but did not find online practical education as effective (81.3%) as online theoretical teaching. The commonly described barriers to online teaching included loss of interaction with educators, inappropriateness in gaining clinical skills, and the instability of the internet connection. Conclusion: Despite the reported benefits, clinical dental students in Egypt preferred the hybrid approach in dental education as distance learning represented a prime challenge to gain adequate clinical dental skills

Cellular transcripts regulated during infections with Highly Pathogenic H5N1 Avian Influenza virus in 3 host systems

<p>Abstract</p> <p>Background</p> <p>Highly pathogenic Avian Influenza (HPAI) virus is able to infect many hosts and the virus replicates in high levels in the respiratory tract inducing severe lung lesions. The pathogenesis of the disease is actually the outcome of the infection as determined by complex host-virus interactions involving the functional kinetics of large numbers of participating genes. Understanding the genes and proteins involved in host cellular responses are therefore, critical for the elucidation of the mechanisms of infection.</p> <p>Methods</p> <p>Differentially expressed transcripts regulated in a H5N1 infections of whole lung organ of chicken, <it>in-vitro </it>chick embryo lung primary cell culture (CeLu) and a continuous Madin Darby Canine Kidney cell line was undertaken. An improved mRNA differential display technique (Gene Fishing™) using annealing control primers that generates reproducible, authentic and long PCR products that are detectable on agarose gels was used for the identification of differentially expressed genes (DEGs). Seven of the genes have been selected for validation using a TaqMan^®based real time quantitative PCR assay.</p> <p>Results</p> <p>Thirty seven known and unique differentially expressed genes from lungs of chickens, CeLu and MDCK cells were isolated. Among the genes isolated and identified include heat shock proteins, Cyclin D2, Prenyl (decaprenyl) diphosphate synthase, IL-8 and many other unknown genes. The quantitative real time RT-PCR assay data showed that the transcription kinetics of the selected genes were clearly altered during infection by the Highly Pathogenic Avian Influenza virus.</p> <p>Conclusion</p> <p>The Gene Fishing™ technique has allowed for the first time, the isolation and identification of sequences of host cellular genes regulated during H5N1 virus infection. In this limited study, the differentially expressed genes in the three host systems were not identical, thus suggesting that their responses to the H5N1 infection may not share similar mechanisms and pathways.</p

Characterization of flow rate and Heat Loss in Heating, Ventilation and Air Conditioning (HVAC) Duct System for Office Building

A building is an assemblage that is firmly attached to the ground and provides the performance of human activities and need to be considered in the daily operation in that building. The improvements in building performance are focused on improving the energy efficiency of buildings. This is approach by designing heating, ventilation and air conditioning (HVAC) duct system due to one of the most utilized energy in maintaining building performance and environment. The objectives of this research is to calculate the air (CFM) supply in office building, to characterize the velocity and head loss in a round and rectangular HVAC ducting system at various duct thickness and to optimize the thickness of the duct in HVAC system according to ASHRAE Standard. The increasing of velocity in duct system shows the increasing of head loss. The round duct design gives the lowest velocity and head loss in HVAC system approximately around 9.35% as compared to rectangular duct at 0.06 inches thickness. Hence, the trends of the head loss and duct thickness has influenced in reducing noise in HVAC duct system in order to select the best design concepts which is round shape design

Young Adult with Canon Ball Lung Metastasis and Unknown Primary: A Case of Primary Pulmonary Myxoid Sarcoma

Extra skeletal Myxoid Chondrosarcoma (EMC) is a rare soft tissue sarcoma, which primarily occurs deep in extremities, especially in the skeletal muscle or tendon. Unusual locations include tongue, retroperitoneum, spine, intracranium, testis, inguinal region, synovium, mammary gland, labium and pleura, however no case of has been described the aggressive involvement of lung with multiple canon ball metastatic atypical chondromyxoid neoplasm with unknown primary. We hereby present a 38 year old Asian male patient initially presented for cough and occasional blood stained sputum with chest pain since few days, found to have multiple canon ball lung lesions which histopathological suggestive of atypical chondromyxoidnbsp sarcoma and primary source remained to be unknown. nbs

Evaluation of Bond Strength Between Carbon Fiber Reinforced Polymer (CFRP) Composites with Modified Epoxy Resins and Concrete

Rehabilitation and strengthening of concrete structures are becoming more significant in civil engineering applications. The use of externally bonded Fiber Reinforced Polymers (FRP) is one of the methods to strengthen and rehabilitate reinforced concrete members, providing noticeable improvement to their capacity in resisting load. Carbon Fiber Reinforced Polymer (CFRP) is used along with epoxy resins to evaluate the bond strength of two commercially available epoxies (EPON 828 and EPON 862) between CFRP and concrete. In addition, three new combinations that resulted from mixing the two epoxies were examined. The mechanical properties of epoxy resins are significantly weaker than this of the CFRP making the epoxy characteristics the determining factor in the quality of the bond strength. Three-point flexural test was conducted to examine the bond strength between the CFRP composites and concrete. Further, differential scanning calorimetry was conducted to examine the glass transition temperature of the resultant epoxies. The results showed that the optimum composition was a mixture of 70% of epoxy 828 and 30% of epoxy 862. Therefore, achieving better bond strength and high glass transition temperature, resulting in CFRP composite with higher fire resistance

Screening of antibacterial activity in marine green and brown macroalgae from the coast of Morocco

Antibacterial activity of methanolic extracts from 32 macroalgae (13 Chlorophyta and 19 Phaeophyta) from the Atlantic and Mediterranean coast of Morocco were evaluated for the production of antibacterialcompounds against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Klebsiella pnomeuniae ATCC 700603 and E. faecalis ATCC 29213. Our results indicate that these species of seaweed collected from the Atlantic and Mediterranean coast of Morocco present a significant capacity of antibacterial activities, which makes them interesting for screening for natural products

Identification of a PhenylthiazoleSmall Molecule with DualAntifungal and Antibiofilm ActivityAgainst Candida albicans andCandida auris

Candida species are a leading source of healthcare infections globally. The limited number of antifungal drugs combined with the isolation of Candida species, namely C. albicans and C. auris, exhibiting resistance to current antifungals necessitates the development of new therapeutics. The present study tested 85 synthetic phenylthiazole small molecules for antifungal activity against drug-resistant C. albicans. Compound 1 emerged as the most potent molecule, inhibiting growth of C. albicans and C. auris strains at concentrations ranging from 0.25–2μg/mL. Additionally, compound 1 inhibited growth of other clinically-relevant yeast (Cryptococcus) and molds (Aspergillus) at a concentration as low as 0.50μg/mL. Compound 1 exhibited rapid fungicidal activity, reducing the burden of C. albicans and C. auris below the limit of detection within 30 minutes. Compound 1 exhibited potent antibiofilm activity, similar to amphotericin B, reducing the metabolic activity of adherent C. albicans and C. auris biofilms by more than 66% and 50%, respectively. Furthermore, compound 1 prolonged survival of Caenorhabditis elegans infected with strains of C. albicans and C. auris, relative to the untreated control. The present study highlights phenylthiazole small molecules, such as compound 1, warrant further investigation as novel antifungal agents for drug-resistant Candida infections