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The heat generation from recent advanced computer chips is increasing rapidly. This creates a challenge in cooling the chips while maintaining their temperatures below the threshold values. Another challenge is that the heat generation in the chip is not uniform where some chip components generate more heat than other components. This would create a large temperature gradient across the chip, resulting in inducing thermal stresses inside the chip that may lead to a high probability to damage the chip. The locations in the chip with heat rates that correspond to high heat fluxes are known as hotspots. This research study focuses on using thermoelectric modules (TEMs) for cooling chip hotspots of different heat fluxes. When a TEM is used for cooling a chip hotspot, it is called a thermoelectric cooler (TEC), which requires electrical power. Additionally, when a TEM is used for converting a chip’s wasted heat to electrical power, it is called a thermoelectric generator (TEG). In this study, the TEMs are used for cooling the hotspots of computer chips, and a TEC is attached to the hotspot to reduce its temperature to an acceptable value. On the other hand, the other cold surfaces of the chip are attached to TEGs for harvesting electrical power from the chip’s wasted heat. Thereafter, this harvested electrical power (HEP) is then used to run the TEC attached to the hotspot. Since no external electrical power is needed for cooling the hotspot to an acceptable temperature, this technique is called a sustainable self-cooling framework (SSCF). In this paper, the operation principles of the SSCF to cool the hotspot, subjected to different operating conditions, are discussed. As well, considerations are given to investigate the effect of the TEM geometrical parameters, such as the P-/N-leg height and spacing between the legs in both operations of the TEC mode and TEG mode on the SSCF performance.

During the COVID-19 pandemic, educational mobile games may play a significant role to facilitate students’ learning. Several studies have indicated that these games using mobile phones may improve students’ learning motivation and effectiveness when they are equipped with appropriate learning strategies. However, investigating the impact of learning strategies in students’ utilization of educational mobile games has received little scholarly attention during the COVID-19 pandemic. Hence, this research proposed two learning games scenarios to fill this gap. In the first scenario, students were offered an educational mobile game with a learning strategy called ‘scaffolding strategy’; while in the second scenario, the same game was offered without the strategy. To achieve this objective, an experimental design with a research model was developed to examine the role of scaffolding learning strategy in students’ use of educational mobile games. In this experimental study, 43 students from two classes participated in the two learning scenarios. The results indicate that educational mobile gaming with the scaffolding learning strategy significantly influenced students’ utilization of the mobile game. In addition, the adoption of the learning strategy significantly affected students’ perceived enjoyment, perceived usefulness, perceived ease of use, and behavioural intention to use, compared with the same game without the learning strategy. The results also indicate that the introduction of the scaffolding learning strategy into the educational mobile game will increase students’ learning effectiveness and motivation.

Fluorescence energy homotransfer offers a powerful tool for the investigation of the state of oligomerization of cell surface receptors on a cell-by-cell basis by measuring the polarized components of fluorescence intensity of cells labeled with fluorescently stained antibodies. Here we describe homotransfer-based methods for the flow cytometric detection and analysis of hetero- and homo-associations of cell surface receptors. Homotransfer efficiencies for two- and three-body energy transfer interactions are defined and their frequency distribution curves are computed from the fluorescence anisotropy distributions of multiple-labeled cells. The fractions of receptors involved in homo-clustering is calculated based on the dependence of the fluorescence anisotropy on the surface concentration of the fluorescently stained antibodies. A homotransfer analysis of the homo- and hetero-clustering of the MHCI and MHCII glycoproteins, the cytokine receptor IL-2Ralpha, transferrin receptor and the receptor-type tyrosine phosphatase CD45 on JY B and Kit-225-K6 T cells is presented. We investigated how various factors such as the type of dye, rotational mobility of the dye and dye-targeting antibody, as well as the wavelength of the exciting light affect the homotransfer. We show that the homotransfer technique combined with the high statistical resolution of flow cytometry is an effective tool for detecting different oligomeric states of receptors by using fluorophores having restricted rotational mobility on the time scale of fluorescence.

Globally, the empowerment of women is a critical and challenging issue. In considering the problem, the researchers sought to investigate Women’s Empowerment (WE) in the context of Saudi Arabia. In this study the researchers applied quantitative methods and collected the cross-sectional data through a questionnaire based on a random sampling technique. The study utilized 314 useable samples to conclude the investigation. Using path analysis through Analysis of Moment Structures (AMOS) version 26.0, the study underlines a positive and significant effect of Economic Empowerment (EE) and Social Empowerment (SE) on WE. On the other hand, Political Empowerment (PE) has a negative effect on WE. Moreover, Self-efficacy (SFY) and Family Support (FS) also positively and significantly affect WE. Regarding the mediating effects, SFY mediates the positive relationship of EE and SE with WE. On the contrary, SFY did not develop a positive relationship between PE and WE. Finally, FS plays a crucial mediating role in developing the association between EE, SE, PE and WE among Saudi Arabian women. This study’s findings support policymakers and planners in developing policies and strategies to boost WE significantly. Finally, through the empirical confirmation between EE, SE, PE, SFY, FS and WE in Saudi Arabia, a Middle East country, this study’s findings add further enrichment to the depth of the literature.

Alkali activated concretes have emerged as a prospective alternative to conventional concrete wherein diverse waste materials have been converted as valuable spin-offs. This paper presents a wide experimental study on the sustainability of employing waste sawdust as a fine/coarse aggregate replacement incorporating fly ash (FA) and granulated blast furnace slag (GBFS) to make high-performance cement-free lightweight concretes. Waste sawdust was replaced with aggregate at 0, 25, 50, 75, and 100 vol% incorporating alkali binder, including 70% FA and 30% GBFS. The blend was activated using a low sodium hydroxide concentration (2 M). The acoustic, thermal, and predicted engineering properties of concretes were evaluated, and the life cycle of various mixtures were calculated to investigate the sustainability of concrete. Besides this, by using the available experimental test database, an optimized Artificial Neural Network (ANN) was developed to estimate the mechanical properties of the designed alkali-activated mortar mixes depending on each sawdust volume percentage. Based on the findings, it was found that the sound absorption and reduction in thermal conductivity were enhanced with increasing sawdust contents. The compressive strengths of the specimens were found to be influenced by the sawdust content and the strength dropped from 65 to 48 MPa with the corresponding increase in the sawdust levels from 0% up to 100%. The results also showed that the emissions of carbon dioxide, energy utilization, and outlay tended to drop with an increase in the amount of sawdust and show more the lightweight concrete to be more sustainable for construction applications.

The main emphasis of this paper is on the power quality based comparison of two identical systems modeled in ETAP, one comprising CFLs as lighting load and the other has fluorescent lights as lighting source. Current waveforms along with its spectrum for the HTs (High Tension side) and LTs (Low Tension side) of distribution transformers, voltage waveforms and their spectrum at different buses have been compared in terms of THDv and THDi at various locations.

The growing population and increasing urbanization have led to a surge in domestic wastewater generation, posing significant challenges for effective and sustainable treatment. The present study demonstrates a novel and sustainable approach for the onsite treatment of domestic wastewater using an integrated settler-based biofilm reactor (ISBR) with efficient biogas generation. The ISBR provides an optimized environment for the growth of biofilm, facilitating the removal of organic pollutants and pathogens. Moreover, the ISBR enables the recovery of a valuable resource in the form of biogas, thus enhancing the overall utility of the treatment process. The performance of the ISBR was comprehensively evaluated at laboratory scale through treating the actual domestic wastewater generated from the hostel of Manipal University Jaipur. The ISBR system was operated under an ambient environment at a hydraulic retention time (HRT) of 24 h. The results demonstrated remarkable efficiency in terms of chemical oxygen demand (COD), total suspended solids (TSS), and coliforms removal, with average removal efficiency being more than 90%. According to the COD mass balance analysis, 48.2% of the influent COD was recovered as bioenergy. The chromatogram revealed a high percentage of methane gas in the collected biogas sample. The field emission scanning electron microscope (FESEM) analysis of the accumulated sludge in the ISBR system depicted the morphology of methanogenic bacteria. Both the experimental and theoretical results confirmed the feasibility and sustainability of the ISBR system at the onsite level.