Structural Insights from Recent CB1 X-Ray Crystal Structures

Over the past 2 years, X-ray crystal structures of the antagonist- and agonist-bound CB1 receptor have been reported. Such structures are expected to accelerate progress in the understanding of CB1 and should provide an exceptional starting point for structure-based drug discovery. This chapter examines the consistency of these X-ray structures with the CB1 experimental literature, including mutation, NMR and covalent labeling studies. These comparisons reveal discrepancies between this literature and the TMH1-2-3 region of each CB1 crystal structure. The chapter also examines crystal packing issues with each X-ray structure and shows that the discrepancies with the experimental literature can be attributed to crystal packing problems that force the N-terminus deep in the binding pocket of the two inactive state structures and force TMH2 to bend at G2.53/S2.54 and invade the binding pocket in the activated state structure. Revision is advisable before these structures are used for structure-based drug discovery

Isolation, characterization, and hydrolytic activities of Geobacillus species from Jordanian hot springs

The present study was conducted to isolate, identify, characterize and to determine the enzymatic activities of the thermophilic Geobacillus species from five Jordanian hot springs. Based on phenotypic characters, eight thermophilic isolates were identified and belonged to the genus Geobacillus. The Geobacillus isolates were abundant in all investigated hot springs. The optimal temperature for growth of the isolates was 60 to 65°C and the optimal pH was 6 to 8. Colonies were light yellow circular to rhizoid. The bacterial cells were Gram positive rods and endospore forming. All isolates produced amylase, caseinase, alkaline and acid phosphatases, esterase (C4), esterase lipase (C8), α-Galactosidase, β-Glucuronidase, β-Glucosidase, and N-Acetyl-β-glucosaminidase. Seven isolates produced leucine and valine arylamidases and five isolates produced naphthol-AS-B1- phsphohydrolase. Lipase (C14) activity from two isolates and α-chymotrypsin activity from three isolates were also detected. The phenotypic characterization of those isolates was confirmed by genotypic method using 16S rDNA sequence analysis. Maximal homology of all eight  isolates to genus Geobacillus was observed. Five of these isolates showed greater than 98% homology with Geobacillus stearothermophilus and one isolate showed 100% homology with Geobacillus thermoglucosidasius. Therefore, 16S rRNA gene sequence analysis can be considered as a valuable genotypic tool for the identification and characterization of thermophilic bacteria at genus level. Moreover, enzymatic products of those isolates could receive considerable attention due to their potential applications in biotechnology.Keywords: Thermophiles, Geobacillus, hydrolytic enzymes, hot spring, 16S rRNA

Effects of a Training Module on Omani Teachers' Awareness of Gifted Students with Learning Disabilities

The COVID-19 pandemic has led to the use of online and e-learning in Omani general and higher education institutions. Consequently, the pandemic imposed contemporary technological challenges when considering training programs for Omani teachers. This research seeks to record proactive steps, at the Omani and Arab levels, to examine the effectiveness of online, in-service teacher training programs. In addition, this research seeks to explore the effects of online training modules on teachers' knowledge of Gifted Students with Learning Disabilities (GSLD). In other words, the research aims to examine the effects of a training module on Omani teachers’ awareness of GSLD. According to a convenience sampling method, a total of 60 Omani teachers participated in the research. Participants were teachers of students with Learning Disabilities (LD) at the resource room program in the Muscat Governate, in the Sultanate of Oman. They were distributed equally into two groups: control (n=30), and experimental (n=30). Following the development of a Self-Awareness Scale (SAS) and the training program module, the SAS was administered to both groups as a pre-test and a post-test. The teachers in the experimental group received a two-week online training module to improve their awareness of GSLD. Results indicated that there were significant differences in the post-test of the SAS in favor of teachers in the experimental group

Design and Techno-economic assessment of a new hybrid system of a solar dish Stirling engine instegrated with a horizontal axis wind turbine for microgrid power generation

The increasing interest in renewable microgrids have motivated the exploration of more sustainable alternatives to traditional energy supply. In this study, a novel hybrid renewable energy-based microgrid power system is proposed, designed and techno-economically assessed. The system consists of a concentrated parabolic solar dish Stirling engine and a horizontal axis wind turbine integrated with a battery bank. The novelty of the study lies in replacing conventional hybrid systems, such as a typical photovoltaic/wind assembly, with a novel solar dish/wind turbine system that has the potential to achieve higher efficiencies and financial competitiveness. The solar dish Stirling engine serves as the primary source of electrical power generation while the horizontal axis wind turbine, in conjunction with a battery bank, supplies backup electricity when the primary source of power is unavailable. The system has been designed through advanced modelling in the MATLAB/ Simulink® environment that efficiently integrates the individual energy technologies. A technical sensitivity analysis has been performed for all the units in order to reduce the respective design limits and identify optimum operational windows. Further, the performance of the model has been tested at two locations in Jordan, and a thorough techno-economic analysis of the integrated system has been conducted. The simulation results show that at the optimal design point the efficiency of the Stirling engine is 37% with a net output power of 1500 kWe. For the horizontal axis wind turbine, a module of 100 kWe with a power coefficient of 0.2–0.24 is suitable for operation in terms of cost, power, torque and farm size. Also, two economic indicators, namely, the levelised cost of electricity and hourly cost, have been calculated. The levelised cost of electricity lies between 0.13 and 0.15 $/kWh while the hourly cost is found to be around 4$/h. Thus, the economic evaluation revealed that the proposed system is very competitive with other integrated renewable energy technologies

Seismic imaging of deep low-velocity zone beneath the Dead Sea basin and transform fault : implications for strain localization and crustal rigidity

Author Posting. © American Geophysical Union, 2006. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 33 (2006): L24314, doi:10.1029/2006GL027890.New seismic observations from the Dead Sea basin (DSB), a large pull-apart basin along the Dead Sea transform (DST) plate boundary, show a low velocity zone extending to a depth of 18 km under the basin. The lower crust and Moho are not perturbed. These observations are incompatible with the current view of mid-crustal strength at low temperatures and with support of the basin's negative load by a rigid elastic plate. Strain softening in the middle crust is invoked to explain the isostatic compensation and the rapid subsidence of the basin during the Pleistocene. Whether the deformation is influenced by the presence of fluids and by a long history of seismic activity on the DST, and what the exact softening mechanism is, remain open questions. The uplift surrounding the DST also appears to be an upper crustal phenomenon but its relationship to a mid-crustal strength minimum is less clear. The shear deformation associated with the transform plate boundary motion appears, on the other hand, to cut throughout the entire crust.Funded by USAID Middle Eastern Regional Cooperation Program grant M21-012, with matching funds by the participating institutions

Photovoltaic Solar Cells and Panels Waste in Jordan: Figures, Facts, and Concerns

Even though the Kingdom of Jordan is moving in the right direction and adopting clean energy sources such as PV plants, the waste problem will eventually emerge within a few decades and will be an overwhelming issue if not addressed early on. According to reports, the installed PV capacity worldwide was around 410 GW in 2017 and is projected to increase to 5000 GW by 2050. Global solar PV waste is anticipated to reach between 5% and 15% of total generation capacity by 2030, with a 25-year average panel lifespan. This study aims to provide an estimation of the amount of PV waste expected within the next decade, and finally expand on the economic and environmental effects. Moreover, this paper's target is to explore the possible effects of PV waste materials in the northern part of Jordan, and the obtained results can be applied to other regions in Jordan. Information about renewable energy in Jordan, retrieved from databases of electricity companies, is utilized to reach an accurate estimation of the amounts of materials that will occur at the end of life. The solar PV panel end of life (EOL) management is a developing field that necessitates additional research and development The obtained findings, figures, and facts about the photovoltaic solar energy sector presented in this study highlight the urgency to develop a suitable system for the collection and management of photovoltaic modules at their end of life.Scopu

Estrogens and the risk of breast cancer: A narrative review of literature

In female mammals, the development and regulation of the reproductive system and non-reproductive system are significantly influenced by estrogens (oestrogens). In addition, lipid metabolism is another physiological role of estrogens. Estrogens act through different types of receptors to introduce signals to the target cell by affecting many estrogen response elements. Breast cancer is considered mostly a hormone-dependent disease. Approximately 70% of breast cancers express progesterone receptors and/or estrogen receptors, and they are a good marker for cancer prognosis. This review will discuss estrogen metabolism and the interaction of estrogen metabolites with breast cancer. The carcinogenic role of estrogen is discussed in light of both conventional and atypical cancers susceptible to hormones, such as prostate, endometrial, and lung cancer, as we examine how estrogen contributes to the formation and activation of breast cancer. In addition, this review will discuss other factors that can be associated with estrogen-driven breast cancer

Effect of Various Local Anthropogenic Impacts on the Diversity of Coral Mucus-Associated Bacterial Communities

The global continued decline in coral reefs is intensifying the need to understand the response of corals to local environmental stressors. Coral-associated bacterial communities have been suggested to have a swift response to environmental pollutants. This study aims to determine the variation in the bacterial communities associated with the mucus of two coral species, Pocillopora damicornis (Linnaeus, 1758) and Stylophora pistillata (Esper, 1792), and the coral-surrounding seawater from three areas exposed to contamination at the Jordanian coast of the Gulf of Aqaba (Red Sea), and also explores the antibacterial activity of these bacteria. Corals were collected from three contaminated zones along the coast, and the bacteria were quantified and identified by conventional morphological and biochemical tests, as well as 16S rRNA gene sequencing. The average number of bacteria significantly varied among the coral mucus from the sampling zones and between the coral mucus and the surrounding seawater. The P. damicornis mucus-associated bacterial community was dominated by members of the classes Gammaproteobacteria, Cytophagia, and Actinomycetia, while the mucus of S. pistillata represented higher bacterial diversity, with the dominance of the bacterial classes Gammaproteobacteria, Actinomycetia, Alphaproteobacteria, and Bacilli. The effects of local anthropogenic impacts on coral mucus bacterial communities were represented in the increased abundance of bacterial species related to coral diseases. Furthermore, the results demonstrated the existence of bacterial isolates with antibacterial activity that possibly acted as a first line of defense to protect and maintain the coral host against pathogens. Indeed, the dynamics of coral-associated microbial communities highlight the importance of holistic studies that focus on microbial interactions across the coral reef ecosystem

Antimicrobial metal-based thiophene derived compounds

A novel series of thiophene derived Schiff bases and their transition metal- [Co(II), Cu(II), Zn(II), Ni(II)] based compounds are reported. The Schiff bases act as tridentate ligands toward metal ions via azomethine-N, deprotonated-N of ammine substituents and S-atom of thienyl moiety. The synthesized ligands along with their metal complexes were screened for their in vitro antibacterial activity against six bacterial pathogens (Escherichia coli, Shigella flexneri, Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus and Bacillus subtilis) and for antifungal activity against six fungal pathogens (Trichophytonlongifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glabrata). The results of antimicrobial studies revealed the free ligands to possess potential activity which significantly increased upon chelation