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Abstract Decarbonizing heat-intensive industries by reusing the waste heat for power or combined heat and power systems is becoming increasingly important to address global warming. The Organic Rankine Cycle has shown a high level of feasibility and performed efficiently for utilizing medium-to-low-grade heat from renewable resources and heat-intensive industries for direct power generation. This study contributes to the field by conducting a techno-economic investigation of various Organic Rankine Cycle configurations to enhance energy conversion when real-life transient waste heat sources are available. These configurations were optimized to maximize energy output along with economic benefits. The non-linear programming by quadratic Lagrangian, a computational unintensive yet accurate optimization algorithm, was utilized for the multi-objective optimization. The optimized cycle configurations showed a 12.57% enhancement of turbine efficiency. Combining regeneration and recuperation enhanced the superheating by 32%, and the optimized air preheater cycle improved the overall objective by 64.2% compared to the pre-optimized conventional cycle, leading to a feasible 1.72-year payback period.

The increasing carbon footprint associated with conventional cooling methods underscores the urgent need for sustainable alternatives. This study investigates the economic and environmental advantages of various solar-thermal cooling systems, with a focus on optimizing their performance across different climate conditions. Employing a multi-objective approach, the research emphasizes exergy-economic indices to optimize selected cycles. The analysis covers multiple refrigeration technologies, including liquid absorption, solid adsorption, and solid desiccant cycles. Results indicate that the liquid absorption cycle performs optimally in hot, arid climates, reducing the payback period to approximately 8 years when optimized. In hot and humid regions, the solid desiccant cycle proves most effective due to its superior humidity control, yielding a payback period of 5.3 years. For cold and mountainous areas, the solid adsorption cycle is preferred, with a payback period of 13.5 years, while moderate and humid climates benefit from the solid desiccant cycle for both cooling and humidity regulation. The exergy-economic factors for the solar refrigeration systems across semi-arid, hot and arid, hot and humid, cold and mountainous, and moderate and humid climates are 0.758, 0.602, 0.698, 0.74, and 0.575, respectively.

Abstract The Middle Jurassic syn-rift sediments of the Khatatba Formation contain not only the principle source rock organofacies in the north Western Desert (NWD), but also several potential sandstone reservoir targets. However, controls on the reservoir quality of the Khatatba facies and spatiotemporal evolution of the reservoir rock types (RRTs) are still blurred. This study integrates seismic, wireline logs, and conventional core data from some wells in the Meleiha development lease in the NWD to investigate the petrophysical characteristics of the Khatatba reservoir facies, and determine the different RRTs. On seismic, Khatatba Formation consists of high reflectivity, continuous reflections displaying an upward decrease in seismic amplitude corresponding to a fining-upward clastic succession of fluvial–tidal facies. These facies display a large-scale pore system heterogeneity, thereby comprising three different RRTs. RRTI and RRTII rocks have a well-connected pore network dominated by capillary and super-capillary pores (> 10 µm), whereas sub-capillary pores (

Graphene nanoplatelets with high thermal diffusivity are being researched for their ability to improve the thermal characteristics of adsorbents. Similarly, ionic liquids with hydrophilic properties have shown promising sorption and thermal attributes. In this study, novel composite adsorbents are developed, comprising few-layered graphene nanoplatelets and specific ionic liquids (ethyl-methylimidazolium methanesulfonate (EMIMCH3SO3) and ethyl-methylimidazolium chloride (EMIMCl)), along with polyvinyl alcohol binder. The composites, known as GP-CL-30-CP and GP-CH3SO3-30-CP, each contain 30% ionic liquid content. The aim is to capitalise on the superior thermal properties of graphene nanoplatelets and the stability and solvation characteristics of ionic liquids to enhance water and cooling production in adsorption-based cooling and desalination processes, addressing challenges in the water–energy nexus. The findings revealed an improvement in the thermal diffusivity of the composites by 167%, which is 76 times higher than the baseline silica gel. There was an increase in water uptake from 0.3534 kg/kg for silica gel to 0.9648 kg/kg for the composites, representing a 174% enhancement in water sorption, and hence more freshwater water production.

Background: Road traffic accidents (RTAs) are a leading cause of mortality and morbidity in the young population and are a growing problem worldwide. This study is a comprehensive analysis of the spatiotemporal patterns of 352,464 RTAs in Saudi Arabia from 2017 to 2018. Methods: This study consists of three principal phases of analysis (exploratory data analysis of the RTA dataset by analyzing population involvement in RTAs and mortality or morbidity, we examined the geographic and temporal distribution of RTA, and we performed a spatial hotspot analysis per region on a monthly basis using local Moran's I hotspot clustering). This study presented the monthly spatiotemporal patterns of RTAs in Saudi Arabia in 1439 Hijri and data were obtained from the Saudi Open Data Portal for all. Results: Four cities, Ar Riyad, Ash Sharqiyah, Makkah, and Jeddah, were in the top 25% of RTA involvement, mortality, and morbidity in Saudi Arabia. Four cities, Ar Riyad, Ash Sharqiyah, Makkah, and Jeddah, were in the top 25% of RTA involvement, mortality, and morbidity in Saudi Arabia. There were 11 injuries and 2 deaths per 100 accidents during the study period. More than 84% and 88% of those who were injured and killed in RTAs were male, respectively. There was a significant decrease in the number of RTAs in the last months of the year (Hajj month in the Hijri calendar) compared to other months in the Makkah region and the Eastern Province. In addition, no significant temporal patterns in daily occurrence rates at the national level. Similarly, there was no significant difference between RTA incidence on weekdays and weekends. Differences between daytime and nighttime were significant, with more accidents occurring during the day. The number of injuries per 1,000 population is the same throughout the year in the provinces of the country. Conclusion: This study identified areas in Saudi Arabia where further investigation is needed to analyze the points that lead to more RTAs and consequently more disabilities and mortalities. [SJEMed 2023; 4(1.000): 012-030]

Abstract Cell motility is critical for tumor malignancy. Metabolism being an obligatory step in shaping cell behavior, we looked for metabolic weaknesses shared by motile cells across the diverse genetic contexts of patients’ glioblastoma. Computational analyses of single-cell transcriptomes from thirty patients’ tumors isolated cells with high motile potential and highlighted their metabolic specificities. These cells were characterized by enhanced mitochondrial load and oxidative stress coupled with mobilization of the cysteine metabolism enzyme 3-Mercaptopyruvate sulfurtransferase (MPST). Functional assays with patients’ tumor-derived cells and -tissue organoids, and genetic and pharmacological manipulations confirmed that the cells depend on enhanced ROS production and MPST activity for their motility. MPST action involved protection of protein cysteine residues from damaging hyperoxidation. Its knockdown translated in reduced tumor burden, and a robust increase in mice survival. Starting from cell-by-cell analyses of the patients’ tumors, our work unravels metabolic dependencies of cell malignancy maintained across heterogeneous genomic landscapes.

With the widespread utilization of solar photovoltaics (PV), it is becoming increasingly important to understand its performance using various configurations to harvest solar energy at the most suitable efficiency, specifically in hot climates. Therefore, this paper compares mono-facial and bi-facial PV cells under the high-temperature desert climate of Sharjah (United Arab Emirates). The optimally tilted and vertical east-west configurations were compared to evaluate the annual energy production for these scenarios. In addition, new parameter, the effect of the rear side layer absorptivity of the mono-facial PV cell, was investigated. The comparative study considered solar radiation, ambient temperature, wind speed, and albedo. The results showed that considering the effect of absorptivity achieves better performance predictions. However, the effect of the absorptivity did not exhibit a significant influence compared to the case with neglected backsheet absorptivity. As such, the PV cell temperature increased by 0.4 °C and 1.4 °C at an albedo of 0.2 and 0.7, considering the actual absorptivity value of 0.2. On the other hand, it is worth mentioning that improper designs result in considerable temperature rises as the absorptivity value increases. Under the investigated conditions and based on the yearlong comparison, the tilted bi-facial performed better than the vertical bi-facial; as the albedo increased from 0.2 to 0.7, the power gain ratio of the tilted bi-facial increased from 7.18% to 20.88% and that of vertical bi-facial from -19.4% to 12.65%.

Concentrated solar power (CSP) technology is a promising renewable energy technology worldwide. However, many challenges facing this technology nowadays. These challenges are mentioned in this review study. For the first time, this work summarized and compared around 143 CSP projects worldwide in terms of status, capacity, concentrator technologies, land use factor, efficiency, country and many other factors. Further, the various challenges facing the spread-out of this system are highlighted in terms of the heat transfer fluids (HTF), various energy storage (ES) technologies, cooling techniques, water management, and the Levelized Cost of Electricity (LCOE). Also, various thermophysical properties of the HTF are compared within the applicable range of the CSP operation. At the end of the review, various hybridization technologies for the CSP with various renewable energy sources, including photovoltaic, wind, and geothermal, are highlighted and compared. The pioneering country in using CSP, leading concentrator technology, suitable ES technology, and efficient hybrid technique based on the LCOE are determined. The analyzed data in this study is essential for predicting the future of the CSP in the markets and its contribution to reducing global warming potential.

Although hollow fiber water gap membrane distillation (HF-WGMD) units offer certain advantages over other MD desalination systems, they still require enhancements in terms of distillate flux and productivity. Therefore, this work proposes a novel configuration by incorporating the helical turns of HF membranes within the water gap channel of the HF-WGMD modules. A fully coupled 3D CFD model is developed and validated to simulate the multifaceted energy conservations and diffusion mechanisms that are inherent to the transport phenomena in the proposed HF-WGMD module. Single and double helical HF membrane designs with different numbers of turns are compared to the reference modules of single and double straight HF membrane designs under various operational conditions. At a feed temperature of 70 °C, a noteworthy 11.4% enhancement in the distillate flux is observed when employing 20 helical turns, compared to the single straight HF membrane module. Furthermore, the specific productivity revealed a maximum enhancement of 46.2% when using 50 helical turns. The thermal performance of the proposed HF-WGMD module shows higher energy savings of up to 35% in specific thermal energy consumption for a one-stage module. Using three stages of single helical modules can increase the gain output ratio from 0.17 for the single stage to 0.37, which represents an increase of 117.6%. These findings indicate the high potential of the proposed approach in advancing the performance of HF-WGMD systems.

Objectives. This study was carried out to delineate the patients’ characteristics and the imaging findings and their relation to some biochemical markers of 31 critically ill patients with MIS-C. Design. A retrospective cross-sectional study including all critically ill MIS-C patients admitted to the PICU from June 23rd to July 22nd, 2020. Results. Eighteen males and 13 females, with a median age of 9 years (interquartile range 6-11) presented mainly with fever (100%) and hypotension (100%). Abnormalities in the chest computed tomography were detected in 22 cases (71%). Consolidation and architecture distortion were detected in 58.1% of patients; bilateral lesions and lower lobe infiltrates, each, was evident in 64.5% of patients, while the peripheral distribution of lesions was seen in 71% of the cases. Pleural thickening and effusion, each, was found in 51.6% of the patients. In this small case series, the presence of high ferritin was significantly associated with the bilaterality of the lesions. Elevated C-reactive protein was associated with the peripheral distribution of the lesions. Thrombocytopenia and hypoalbuminemia were significantly correlated with the CT disease stage and CT severity score respectively. Conclusions. Although a few children in this group of MIS-C patients presented with respiratory manifestations, yet, most of them demonstrated significant radiological lung involvement, which necessitates a longer-term follow-up.

Recently, water desalination (WD) has been required for the supply of drinking water in a number of countries. Various technologies of WD utilize considerable thermal and/or electrical energies for removing undesirable salts. Desalination systems now rely on renewable energy resources (RERs) such as geothermal, solar, tidal, wind power, etc. The intermittent nature and changeable intensity constrain the wide applications of renewable energy, so the combination of energy storage systems (ESSs) with WD in many locations has been introduced. Thermal energy storage (TES) needs a convenient medium for storing and hence reuses energy. The present work provides a good background on the methods and technologies of WD. Furthermore, the concepts of both thermal and electrical energy storage are presented. In addition, a detailed review of employing ESSs in various WD processes driven by RERs is presented. The integration of energy storage with water desalination systems (WDSs) based on renewable energy has a much better capability, economically and environmentally, compared with conventional desalination systems. The ESSs are required to guarantee a constant supply of fresh water over the day.

The use of fossil fuels has contributed to climate change and global warming, which has led to a growing need for renewable and ecologically friendly alternatives to these. It is accepted that renewable energy sources are the ideal option to substitute fossil fuels in the near future. Significant progress has been made to produce renewable energy sources with acceptable prices at a commercial scale, such as solar, wind, and biomass energies. This success has been due to technological advances that can use renewable energy sources effectively at lower prices. More work is needed to maximize the capacity of renewable energy sources with a focus on their dispatchability, where the function of storage is considered crucial. Furthermore, hybrid renewable energy systems are needed with good energy management to balance the various renewable energy sources’ production/consumption/storage. This work covers the progress done in the main renewable energy sources at a commercial scale, including solar, wind, biomass, and hybrid renewable energy sources. Moreover, energy management between the various renewable energy sources and storage systems is discussed. Finally, this work discusses the recent progress in green hydrogen production and fuel cells that could pave the way for commercial usage of renewable energy in a wide range of applications.

Increasing the cycle efficiency of Organic Rankine Cycles is an important R&D area. In this study, an effort has been made to optimize various parameters related to the axial flow turbine to maximize an ORC's efficiency. First, a numerical model for a small-scale single-stage axial flow turbine was developed and coupled with a 1D model of an existing ORC system. Then, a parametric study was undertaken for the system working under various turbine inlet conditions, such as turbine pressure ratios and working fluids. An optimization study was undertaken for the turbine flow profile using a low computational intensity Artificial Neural Network coupled with Genetic Algorithm optimization. Investigating the turbine losses revealed that the Mach Number is the most influential factor, which depends on the molar mass of the working fluid. Our study revealed that increasing the degree of superheat by up to 200% enhanced the turbine and overall cycle efficiency by 11% and 5%, respectively. Increasing the turbine total-to-static pressure ratio from 3 to 10 improved the turbine and cycle efficiency by up to 41% and 15%, respectively. Optimizing the turbine's flow profile enhanced the overall loss coefficient by 13.7%, the turbine's total-to-static efficiency by 5.2%, and the overall cycle efficiency from 8.78% to 9.02%.

Abstract In this study, a surface diffraction two-dimensional (2D) grating structure was placed on the topmost layer of distributed Bragg reflectors (DBRs) for biosensing. Bloch surface wave (BSW) resonance was realized by coupling a 2D subwavelength hole-array grating and could be excited at different locations: the surface of 2D-grating layer or the inter-face between the DBR and bio-solution. Material losses in the multilayer dielectric were measured to test the robustness of this scheme. Both the surface diffraction-grating BSW (DG-BSW) and the alternative guided grating-coupled BSW (GC-BSW) configuration showed markedly enhanced angular sensitivity compared to conventional prism-coupled schematics. Exciting these modes using a grating-coupling technique appears to yield different extreme sensitivity modes with a maximum of 1190°/RIU for DG-BSW and 2255°/RIU for GC-BSW. Refractive index sensors with a high figure of merit may be realized via such compact configurations.

Adsorption heat storage is the most feasible technology for heating decarbonization, which can store large quantities of waste and renewable heat for an exceptionally long time. However, utilizing adsorption heat storage in geographical locations with sub-zero ambient conditions is challenging. Therefore, this paper experimentally investigates the use of ethanol as a working fluid paired with silica gel for adsorption heat storage and utilizes sub-zero ambient as the heat source. The heat storage characteristics, heat charging/discharging cyclic performance, and energy conversion performance via exergy analysis were determined under realistic operating conditions and benchmarked against the widely investigated silica gel/water. Ethanol adsorbate was successfully utilized as a working fluid to employ the evaporators operating under sub-zero ambient conditions. Silica gel/ethanol showed the most significant net cyclic uptake, twice that of silica gel/water. However, the physical characteristics of ethanol molecules led to a degree of non-desorbed fluid, which hampered such potential to store 18.08 kJ/kgads under a sub-zero evaporator temperature and 24.84 kJ/kgads for an above-zero evaporator temperature compared to silica gel of 155.12 kJ/kgads operating an above-zero evaporator temperature. On the other hand, silica gel/ethanol showed the fastest heat charging/discharging rate that can shorten the cycle time by 45%. The major contributor to exergy destruction was the exergy transferred by charging heat, which was five times the discharging heat due to the high charging temperature.

Different methodologies used to evaluate acoustic performancein ineducational lecture hall. Theses technical methods have been used in order to define theacoustic problems in lecture hall and suggest acoustic and architecture treatments to solvethese acoustic problems. The methods that used for acoustic analysis were Sabin, Eyring,Arau-puchades and ODEON. This paper is foucing on acoustic performance in lecturehall 2 in Tanta Engineering. Acoustic study has been done for lecture hall as follows:Evaluation the acoustic performance by field measurements for reverberation time,manual calculation and acoustic simulation; ODEON software. Different acousticperformance analysis was performed. Different acoustic and architecture treatments weresuggested based on the analysis. The final results of room acoustics of different casescarried on the hall were compered to the international requirements for educationalspaces. The main problems based on the acoustic analysis are the increase of hall height,architecture design of ceiling and hard covering of the internal surfaces

Abstract Background Rhododendron species have been traditionally used in countries like China, Nepal, Russia and North America for treating human diseases. These species are known to be a good source of polyphenolic plant secondary plant metabolites. They are known to have beneficial health properties for humans and have been used to treat diseases like asthma, skin diseases. In this contribution we investigate the phenolic profile and antibacterial activity of extracts from several plant organs including for the first time from leaves of different development stages. Methods In this study, the polyphenolic profile of fruits, flowers and leaves of different ages of Rhododendron ambiguum and Rhododendron cinnabarinum were studied by using HPLC–MS and compounds identified based on high resolution masses and identity of tandem mass spectra, UV/VIS spectra and retention times if compared to standards. Results Fifty-nine different polyphenols including isomers were identified in these species by their fragmentation pattern and high resolution data. Also, the antibacterial activity of these parts (leaves, fruits and flowers) against gram-positive bacteria was studied. Conclusion The leaves and fruits contained more polyphenols than the flowers. With the exception of flowers, the fruits and leaves of both species were also determined to have a significant antibacterial effect against four gram-positive bacteria.

Background: Regardless of the agent, the inflammatory response is interconnected with infection. Mostly the initial response to infection is severe sepsis and characterized by a pro-inflammatory state, which then progresses to an anti-inflammatory state that develops and favors secondary infections (Florescu and Kalil, 2011) [1]. T-helper 1 (Th1) cells activated by microorganisms increase transcription of pro-inflammatory cytokines such as tumor necrosis factor (TNF-α), interferon-γ (INF-γ), and interleukin-2 (IL-2) (Hotchkiss and Karl, 2003; Brown and Jones, 2004; Russell, 2006) [2–4]. Different cytokines, TNF-α, interleukins, lymphokines, monokines, IFN-γ, colony-stimulating factor (CSF) and transforming growth factors, released from endothelial cells and subsequently from macrophages can induce lymphocyte activation and infiltration at the sites of infection and will exert direct antiviral effects. Subsequently, with the shift toward an anti-inflammatory state, activated T-helper 2 (Th2) cells secrete interleukin-4 (IL-4) and interleukin-10 (IL-10) (Hotchkiss and Karl, 2003; Russell, 2006) [2,4]. Sometimes, T cells can become anergic and fail to proliferate as wells producing cytokines (Hotchkiss and Karl, 2003) [2]. Type I IFN has a potent anti-influenza virus activity, it induces transcription of several interferon-stimulated genes, which in turn restrict viral replication (Garcia-Sastre, 2011) [5]. However, the influenza virus developed several mechanisms to evade IFN response as NS1 protein, IFN-antagonist produced by the virus, PB1–F2 proteins that inhibit IFN induction, the viral polymerase inhibits IFN function, and M2 protein prevents toll-like receptor (TLR) induction (Garcia-Sastre, 2011) [5].Influenza virus can also trigger the deregulation of the innate immune system with excessive cytokines release leading to potentially harmful consequences (Teijaro et al., 2011) [6]. Abnormal immune response to influenza can lead to endothelial damage through the remodeling of the cellular cytoskeleton, loss of intercellular junctional integrity, cellular apoptosis, deregulation of coagulation, the consequent alteration of microvascular permeability, tissue edema, and shock (Steinberg et al., 2012) [7]. This increase in permeability of the endothelium is mainly due to the intercellular pathways and to a lesser extent through the transcellular leak (Steinberg et al., 2012) [7]. Such vascular hyperpermeability and multi-organ failure with severe edema, shock, acute lung injury, and even acute encephalopathy have been described in severe influenza infections (Wang et al., 2010; Armstrong et al., 2013) [8,9]. Novel drugs and vaccines such as peramivir, baloxavir marboxil, and 4 egg-based quadrivalent inactivated influenza vaccines have been added recently [10]. These changes require better and more efficient diagnostic and therapeutic approaches to avoid a fatal progression. I would like to report a child patient with H1N1 influenza, who developed rapid fatal viral septicemia.

Objective: To investigate the possible role of anti-annexin A5 antibodies in inducing recurrent miscarriage. Design: Cross-sectional study. Setting: Benha University Hospital. Participants and interventions: Pregnant women during the first trimester of pregnancy with a history of three or more consecutive pregnancy losses were compared to Multigravidae women during the first trimester of pregnancy with no history of pregnancy losses for group II. Women were screened for anti-annexin A5 antibodies. Results: There were no statistically significant correlations between anti-annexin A5 antibodies in both groups (P>0.05). Conclusion: The present study did not confirm that anti-annexin A5 antibodies have significance in predicting RM when measured in healthy women.

Heat stress during hot season enhances oxidative stress, alters hormonal secretion and adversely affects reproductive performance. So, it's necessary to supply antioxidants such as vitamin E and selenium. This work aimed to investigate the impact of vitamin E and selenium administration on reproductive performance before ovsynch synchronization and artificial insemination (AI) in Friesian cows during hot season. Twenty ovsynchsynchronized Friesian cows were divided according to the time of vitamin E and selenium administration into four groups (each 5 cows), G1 control group without any administration, G2 administered pre-synchronization, G3 administered at AI, G4 administered two doses pre-synchronization and at AI. Follicular functions during synchronization period revealed a significant increase in both follicle number and diameter of G2 and G4 compared to G1 and G3. Blood samples were collected from all cows weekly from 0-day to 5th week post AI for hormones and antioxidant detection. Serum analysis results revealed increased progesterone, prolactin, CAT, SOD, GSH and total antioxidant capacity (TAC), while decreased cortisol and MDA of G4 compared to G1, G2, and G3. Pregnancy detection was performed at 60 days post-AI. Conception rates were 40, 60, 60, and 80% in G1, G2, G3 and G4, respectively. Therefore, vitamin E and selenium administration improve antioxidant activities and overcome oxidative stress providing a better impact on reproductive performance even in hot season. [ABSTRACT FROM AUTHOR]