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The present work presents a literature review of solar-driven adsorption desalination systems (ADS) from the perspective of hybrid systems, adsorption materials, and system configurations. The evaluation criteria were based on the daily water production rate (SDWP), gain output ratio, coefficient of performance (COP), and the specific cooling power (SCP) of the dual-cooling and desalination systems. Recommendations for effective systems that require further research and development to increase water productivity and enhance system performance are also mentioned. First, concerning hybrid systems, adding an ejector to the adsorption desalination cycle showed a significant improvement in SDWP, reaching 40 m3/ton per day (TPD). In comparison, using two ejectors in the ADS integrated with HDH reached 83.1 m3/TPD at a cost estimated at 1.49 $/m3. Secondly, concerning system configurations, a wire wound finned tube heat exchanger of ADS achieved high performance. The SDWP, SCP, and COP were 23.5 m3/TPD, 682 W/kg, and 0.32, respectively. Thirdly, concerning adsorption materials, the results showed promising adsorbent materials in the range of solar energy temperatures, and on top of them was sodium polyacrylate (SP)/CaCl2, where SDWP and COP were about 45 m3/TPD and 0.67, respectively, while the cost was estimated at 3.8 $/m3. Finally, it was recommended to introduce 2D adsorbents to improve the adsorption properties and heat exchangers with 3D structures to improve the overall heat transfer coefficient of ADS.

Background: Fractures of the distal radius was found to be one of the most common skeletal injuries treated by orthopedic or trauma surgeons Objectives: To evaluate the outcome after operative treatment of unstable distal radius fractures to obtain good alignment through different methods of treatment as closed reduction and pinning, bridging and open reduction with volar plate-and-screw fixation. Patients and methods: Our study was a prospective, randomized trial conducted between 2018 and 2019 including 40 patients with displaced, unstable fractures of the distal radius .They were randomized to be managed either by ligamentotaxis supplemented with K-wire fixation or with volar plate fixation with similarity of both groups in the compared variables including age, gender ,mode of trauma , medical co-morbidities and the pattern of fracture. Results: The study was conducted on 40 patients with the mean age of ligamentotaxis group 38.9 years (Range 22-57), while the plating group was 39.45 years (Range 29-51). More than half of patients underwent ligamentotaxis were males and 60% of patients in the plating group were females .Patients in ligamentotaxis group had either road traffic accident or fell on ground with almost equal proportions, but in the plating group falling on ground was the most common. AO fracture type B was the most common among our sample. No statistically significant difference was found between both groups neither at 3 months nor at 6 months follow up. However, the Mayo score showed statistically significant improvement along the follow up Conclusions: We concluded that there is no evidence for the superiority of one treatment over the other either using locking plate and screws or ligamentotaxis supplemented by k wires.

The Um Ara granites are a suite of granitoid rocks located in the southern part of the Eastern Desert of Egypt. The integration of various electron probe micro analyzer (EPMA) techniques, such as backscattered electron (BSE) imaging, X-ray compositional mapping, and wavelength dispersive spectrometry (WDS), has provided valuable insights into the alteration process of zircon in the Um Ara granite. The zircon exhibits high concentrations of non-formula elements such as P, Al, Ca, Fe, Ti, and REEs, suggesting that the alteration involved coupled dissolution-reprecipitation processes influenced by aqueous fluids. The negative correlations between Zr and the non-formula elements indicate that these elements were incorporated into zircon at the expense of Zr and Si, significantly affecting the distribution and fractionation of REEs in the original zircon. Based on the presented data and literature knowledge, the sequence of alteration events is proposed as follows: (1) initial zircon crystallization around 603 Ma accompanied by the formation of other U- and Th-bearing minerals like xenotime, thorite, monazite, and apatite; (2) long-term metamictization leading to fractures and cracks that facilitated fluid circulation and chemical changes; (3) a major hydrothermal event around 20 Ma that released a suite of non-formula elements from the metamicted zircon and associated minerals, with the enriched hydrothermal fluids subsequently incorporating these elements into the modified zircon structure; and (4) further low-temperature alteration during subsequent pluvial periods (around 50,000–159,000 years ago), facilitated by the shear zones in the Um Ara granites, may have allowed further uptake of non-formula elements. The interplay between hydrothermal fluids, meteoric water, and the shear zone environments appears to have been a key driver for the uptake of non-formula elements into the altered zircon.

Abstract Wireless sensor networks (WSNs) are used in many different fields. One of the most recent and rapidly expanding applications is the Internet of Things (IoT), which enables the connectivity of numerous objects or devices over the Internet. However, WSNs have a bigger concern about battery power than mobile ad hoc networks, which shortens the network's lifetime. As a result, extensive research has been done on lowering WSNs' energy usage. Designing a hierarchical clustering algorithm is one of many methods for lowering the energy consumption of WSNs. Given the restricted hardware capabilities of the sensor nodes, modeling and building energy-efficient routing solutions to enhance the overall network lifetime has emerged as one of the most crucial approaches in wireless sensor networks. Cluster-based heterogeneous routing protocols, a typical feature of routing technology, have demonstrated efficacy in managing topology, energy consumption, data collection or fusion, dependability, or stability in distributed sensor networks. The existing Distributed Energy-Efficient Clustering (DEEC) clustering protocol is changed in this study by switching the power level between the nodes and adding a threshold limit for cluster head selection. The number of packets sent to a base station increases by 843% when comparing the proposed improved DEEC protocol to the existing DEEC protocol, increasing the number of living nodes to more than 10,000 rounds, or over 30,000 rounds, which can be used to extend the WSN lifetime. The suggested algorithm outperforms alternative energy-efficient protocols in terms of stability period and network lifetime under various scenarios of area, energy, and node density.

The Neoproterozoic period in the Jabal Sayid and Dayheen areas is characterized by three distinct magmatic phases: an early magmatic phase of granodiorite–diorite association, a transitional magmatic phase of monzogranites, and a highly evolved magmatic phase of peralkaline granites and associated pegmatites. The presence of various accessory minerals in the peralkaline granites and pegmatites, such as synchysite, bastnaesite, xenotime, monazite, allanite, pyrochlore, samarskite, and zircon, plays an important role as contributors of REEs, Zr, Y, Nb, Th, and U. The geochemical characteristics indicate that the concentration of these elements occurred primarily during the crystallization and differentiation of the parent magma, with no significant contributions from post-magmatic hydrothermal processes. The obtained geochemical data shed light on the changing nature of magmas during the orogenic cycle, transitioning from subduction-related granodiorite–diorite compositions to collision-related monzogranites and post-collisional peralkaline suites. The granodiorite–diorite association is thought to be derived from the partial melting of predominantly metabasaltic sources, whereas the monzogranites are derived from metatonalite and metagraywacke sources. The peralkaline granites and associated pegmatites are thought to originate from the continental crust. It is assumed that these rocks are formed by the partial melting of metapelitic rocks that are enriched with rare metals. The final peralkaline phase of magmatic evolution is characterized by the enrichment of the residual melt with alkalis (such as sodium and potassium), silica, water, and fluorine. The presence of liquid-saturated melt plays a decisive role in the formation of pegmatites.

Adsorption systems for desalination, drying, and cooling applications could be powered by renewable energy sources. Thus, it is a promising technology for solving energy and water problems. Designing an efficient adsorption system and evaluating its performance depend mainly on the adsorption isotherms and kinetics of nanoporous materials. The present work designs and manufactures a precise gravimetric sorption apparatus to measure the adsorption isotherms and kinetics of water vapor onto porous materials. It is equipped with a high-precision mass balance to record the change in mass of the tested sample. The main feature of the present apparatus is using an ultrasonic device to generate water vapor allowing easy control of the water vapor flow rate and operating pressure. This novel approach leads to a significant reduction in the apparatus capital cost. To confirm the accuracy and reliability of the proposed instrument, the adsorption kinetics and isotherms of water vapor onto three different materials are measured using the proposed apparatus and compared to the corresponding data in literature. The maximum deviation is found to be less than 4%, indicating the high accuracy of the proposed instrument. During the repeatability tests, a maximum uncertainty of 1.1% is observed at a relative pressure of 0.8, which is within the accuracy of the electronic mass balance. Accordingly, it is confirmed that the developed apparatus could measure the adsorption isotherm and kinetics of water vapor onto nanoporous materials with high accuracy and reliability.

The Jabal Al Bayda, located in the Hijaz terrain of northwest Saudi Arabia, comprises magmatic rocks that represent the ending phase in the Precambrian development of the Arabian Shield. Two granitic suites have been studied petrologically and geochemically, the monzogranite and alkali granite suites, to gain knowledge about their origin and geotectonic implications. The geochemical characteristics of the monzogranites align with their formation in a subduction-related environment. These rocks have a composition that is rich in strontium and barium, and low in rubidium, and displays a high-K calc-alkaline to shoshonitic nature. In contrast, alkali granites typically have lower concentrations of Sr and Ba, and higher rubidium contents. The differences in geochemical composition between monzogranites and alkali granites found in Jabal Al Bayda indicate differences in their origin and geotectonic environment. The evolution of granitoid magmatism in the Jabal Al Bayda area is linked to the Hijaz orogenic cycle, during which northwest-dipping subduction led to the formation of the Midyan, Hijaz, and Jeddah arc assemblage, followed by the collision and accretion of these arcs along the Yanbu and Bir Umq sutures. Due to crustal thickening during the subduction-related stage, the deeper parts of the overlying metagraywackes and metatonalites contribute melt to the early crustal magma, which eventually solidifies to form monzogranites. Later on, during the post-orogenic stage, anatexis of metapelites can occur, leading to the generation of magmas that give rise to alkali granites.

The Um Ara granites are a suite of granitoid rocks located in the southern part of the Eastern Desert of Egypt. The integration of various electron probe micro analyzer (EPMA) techniques, such as backscattered electron (BSE) imaging, X-ray compositional mapping, and wavelength dispersive spectrometry (WDS), has provided valuable insights into the alteration process of zircon in the Um Ara granite. The zircon exhibits high concentrations of non-formula elements such as P, Al, Ca, Fe, Ti, and REEs, suggesting that the alteration involved coupled dissolution-reprecipitation processes influenced by aqueous fluids. The negative correlations between Zr and the non-formula elements indicate that these elements were incorporated into zircon at the expense of Zr and Si, significantly affecting the distribution and fractionation of REEs in the original zircon. Based on the presented data and literature knowledge, the sequence of alteration events is proposed as follows: (1) initial zircon crystallization around 603 Ma accompanied by the formation of other U- and Th-bearing minerals like xenotime, thorite, monazite, and apatite; (2) long-term metamictization leading to fractures and cracks that facilitated fluid circulation and chemical changes; (3) a major hydrothermal event around 20 Ma that released a suite of non-formula elements from the metamicted zircon and associated minerals, with the enriched hydrothermal fluids subsequently incorporating these elements into the modified zircon structure; and (4) further low-temperature alteration during subsequent pluvial periods (around 50,000–159,000 years ago), facilitated by the shear zones in the Um Ara granites, may have allowed further uptake of non-formula elements. The interplay between hydrothermal fluids, meteoric water, and the shear zone environments appears to have been a key driver for the uptake of non-formula elements into the altered zircon. [ABSTRACT FROM AUTHOR]

Samar A Ahmed,1 Archana P Kumar,2,3 Nourhan F Wasfy,4 Nagwa N Hegazy,5 Enjy Abouzeid,4 Mohammed A Hassanien,6,7 Mohamed H Shehata,8,9 W Cliff Kayser III,10 Randa M Mostafa,11 Yawar H Khan,12 Hossam Hamdy13 1Forensic Medicine and Clinical Toxicology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt; 2Medical Education Unit, College of Medicine and Medical Sciences, Arabian Gulf University, Manama, Bahrain; 3Department of Physiology, Sri Ramachandra Medical College and Research Institute, SRIHER, Chennai, Tamil Nadu, India; 4Medical Education Department, Faculty of Medicine, Suez Canal University, Ismailia, Egypt; 5Family Medicine Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt; 6Educational Affairs, College of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia; 7College of Medicine, Tanta University, Tanta, Egypt; 8Family and community medicine department, College of Medicine and Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain; 9Faculty of Medicine, Helwan University, Helwan, Egypt; 10Six SEED Partners, Washington, DC, USA; 11Department of Physiology, Faculty of Medicine, Benha University, Benha, Egypt; 12Riphah International University, Islamabad, Pakistan; 13Gulf Medical University, Ajman, United Arab EmiratesCorrespondence: Samar A AhmedForensic Medicine and Clinical Toxicology Department, Faculty of Medicine, Ain Shams University, Cairo, EgyptEmail SAMAR@med.asu.edu.egBackground: Crises in academia can best be dealt with as a polarity that needs to be leveraged rather than a problem that needs to be solved. This work aimed at utilizing the Polarity Approach for Continuity and Transformation (PACT)™ to establish a guide for medical schools during times of crisis to minimize the effect of crisis-driven decisions on strategic growth.Subjects and Methods: A qualitative study following the 5-Steps of the PACT process was conducted. A virtual mapping session was held with 108 medical educators from 22 countries to determine the upsides and downsides of strategic orientation and crisis management subsequently.Results: Four polarity maps were generated identifying four tension areas; University reputation, mission, teams, and individuals followed by a 72-item assessment and another mapping session to map the warning signs and action steps. A comparison between private school scores and the whole cohort of respondents showed that private schools had the least problems in team-oriented work.Conclusion: This study highlighted the importance of taking measures to communicate the mission and supporting team functions inside universities either by enhancing resources or utilizing time and effort-saving strategies.Keywords: polarity, strategy, planning, crisis, medical, education

Nada Al-Yousuf1, Salah Eldin Kassab2,3, Hasan Alsetri4, Hossam Hamdy51Department of Opthalmology, King Abdullah Medical City, Manama, Kingdom of Bahrain; 2Department of Physiology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt; 3Department of Basic Medical Sciences, College of Medicine, Gulf Medical University, Ajman, United Arab Emirates; 4Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA; 5Department of Surgery, Gulf Medical University, Ajman, United Arab EmiratesCorrespondence: Nada Al-YousufKing Abdullah Medical City, 61, King Abdulaziz Avenue, Manama, Kingdom of BahrainTel +973 77310071Fax +973 77310001Email nyousuf10@gmail.comPurpose: We have previously developed an instrument for students’ evaluation of clinical teachers that we called Visual Indicators of Clinical Teaching and Learning Success (VITALS). This study measures the reliability of VITALS as an instrument for student evaluation of clinical tutors. Additionally, the study explores the minimum number of student raters necessary for an acceptable reliability, and provides evidence of construct validity of the evaluation scores.Materials and Methods: This retrospective study included 1825 evaluation forms completed by medical students evaluating clinical tutors using the VITALS instrument. Reliability was measured by applying generalizability theory (G-theory) analysis using a two-facet design (raters and items). A D-study was used to determine the minimum number of raters required to achieve a reliability ≥ 0.80. Face validity was tested by measuring tutors’ degree of agreement with the items of the study instrument.Results: The overall G-coefficient was 0.89. The subject of measurement (clinical tutors’ scores) represented 15.8% of the variance across all tutors and items. The variance due to the interaction between raters (students) and tutors contributed to 43.5%, while the variance due to items was negligible. The remaining 40% of the variance was due to unexplained sources of error. The D-study demonstrated that a minimum of 12 raters (students) are required to achieve a reliability of 0.80. Finally, most of the clinical tutors agreed that all items in the instrument were appropriate.Conclusion: We demonstrate that VITALS exhibits good psychometric properties. There should be at least 12 students rating each clinical tutor to have an acceptable level of reliability for the study instrument. Face validity of the study instrument was evidenced by its high level of approval among clinical tutors.Keywords: clinical teaching, tutors’ evaluation, reliability, validity, generalizability theory

Radiation detection can provide a reliable means of detecting radiological material. Such capabilities can help to prevent nuclear and/or radiological attacks, but reliable detection in uncontrolled surroundings requires algorithms that account for environmental background radiation. The Berkeley Data Cloud (BDC) facilitates the development of such methods by providing a framework to capture, store, analyze, and share data sets. In the era of big data, both the size and variety of data make it difficult to explore and find data sets of interest and manage the data. Thus, in the context of big data, visualization is critical for checking data consistency and validity, identifying gaps in data coverage, searching for data relevant to an analyst's use cases, and choosing input parameters for analysis. Downloading the data and exploring it on an analyst's desktop using traditional tools are no longer feasible due to the size of the data. This paper describes the design and implementation of a visualization system that addresses the problems associated with data exploration within the context of the BDC. The visualization system is based on a JavaScript front end communicating via REST with a back end web server.

There is a growing potential use of molybdenum disulfide (MoS2) nanosheets loaded in polyvinylidene fluoride (MoS2/PVDF) in the fields of optoelectronics, ion batteries, and energy storage applications. The one-pot hydrothermal route was used to obtain exfoliated MoS2. The MoS2 nanoflakes were used to obtain MoS2/PVDF nanocomposite films by the solution casting process. The weight percent of MoS2 were 0, 0.1, 0.3, 0.5, 1, 3, 5, 10, and 20 wt% of the total weight of PVDF in the nanocomposite films. After annealing of the PVDF and MoS2/PVDF samples at 160 °C, the FTIR study showed many spectral changes including the spectral shift to high wavenumbers and the appearance of new peaks. These spectral changes indicate increasing of crystallinity, strong molecular bonds, and some crystal phase transition from γ to the β phase. Using Davis Mott's relation, the bandgap of MoS2/PVDF nanocomposites before and after annealing was determined. As the concentrations of MoS2 increase, the values of the optical bandgap decrease from 5.72 to 1.83 eV. Annealing the MoS2/PVDF nanocomposite at 160 °C resulted a remarkable decrease in the values of the bandgap energies from 5.64 to 1.16 eV. Tuning the bandgap energy could be achieved by a polynomial fitting to the experimental results. The X-ray diffraction (XRD) showed that PVDF/MoS2 nanocomposite films are amorphous, upon annealing at 160 °C partial crystallization occurred; however, the incorporation of MoS2/PVDF obstructs the crystallization of the MoS2/PVDF nanocomposite films.

Background Several surgical treatment methods have been proposed for the treatment of stable vitiligo, but they remain inadequate in terms of patient satisfaction. Objective To assess the efficacy and safety of a modified autologous cultured hair follicle outer root sheath (HF-ORS) cell suspension transplantation in the treatment of stable vitiligo lesions, and to compare it with transplantation of autologous non-cultured HF-ORS cell suspension for the same patient. Patients and methods Twenty-four patients were enrolled in this prospective controlled study. Hairs were epilated, and HF-ORS cell suspensions were prepared using two methods for the same patient. The recipient site was prepared by CO2 laser resurfacing. Assessment of cellular activity and viability included cellular melanin content determined by enzyme-linked immunosorbent assay and measurement of the fold change in premelanosome (Pmel-17) gene expression. The patients were followed-up for 6 months postprocedure. Results Nineteen patients completed the study. The results demonstrated that the cultured method showed superior repigmentation response in 15 (79%) patients, three (16%) responded equally, and one (5%) was more tolerant of the noncultured method. Conclusion Cultured autologous HF-ORS melanocytes show superior repigmentation response, increased melanin content, and upregulated gene expression of Pmel-17 than that of noncultured ones. However, the study also demonstrated that both methods are potential options for the treatment of stable vitiligo.

Global warming and climate change, accompanied and assisted by rapid economic and population growth, are causing a sharp rise in cooling demands and stressing the already-limited supply of freshwater for many countries worldwide, especially those developing under hot-climate conditions. Thus, it is imperative to find solutions to meet cooling and freshwater needs without negatively affecting the environment and exacerbating the global warming problem. Solar-driven hybrid desalination/cooling technologies are a promising solution that can help in reducing greenhouse gas emissions and increasing overall efficiency and energy savings. The present study summarizes research efforts in meeting cooling and freshwater demands using the available solar resources. Various solar desalination technologies, such as multi-effect distillation (MED), single and multi-stage flash (MSF), reverse osmosis (RO), adsorption, absorption desalination, and membrane distillation (MD), and their integration with different cooling technologies, are reported. The study reported system performance indicators, such as water production rate, cooling capacity, Coefficient of Performance, and freshwater cost.

Abstract Thirty-four bacterial isolates were isolated from soil samples collected from the North Western Coast and a water sample collected from brackish water at Siwa Oasis, Matrouh Governorate, Egypt. Only six isolates showed chitinase activity when screened on colloidal chitin agar medium. The highest chitinolytic activity was achieved by a bacterial isolate labeled as A.S. This isolate was identified as Aeromonas hydrophila based on analysis of 16S rRNA gene sequence and morphological, physiological, and biochemical characteristics. Optimization of the cultural conditions for maximum chitinase production by A. hydrophila revealed that the highest level of chitinase was recorded when the bacterium was grown in malt nitrogen-based medium containing 1% colloidal chitin at pH7 for 48 h incubation at 30 °C. Crude chitinase from isolate A. hydrophila was evaluated against first instar larvae of the greater wax moth; Galleria mellonella L. (Lepidoptera: Pyralidae) at different concentrations of 0, 185, 205, 235, 265, 295 U/mg protein. It increased larval and pupal mortality rates in a concentration-dependent manner. The tested crude chitinase significantly induced a decrease in adults’ emergence rate and their fecundity.