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Hybrid renewable energy systems with photovoltaic and energy storage systems have gained popularity due to their cost-effectiveness, reduced dependence on fossil fuels and lower CO2 emissions. However, their techno-economic advantages are crucially dependent on the optimal sizing of the system. Most of the commercially available optimization programs adopt an algorithm that assumes repeated weather conditions, which is becoming more unrealistic considering the recent erratic behavior of weather patterns. To address this issue, a data-driven framework is proposed that combines machine learning and hybrid metaheuristics to predict weather patterns over the lifespan of a hybrid renewable energy system in optimizing its size. The framework uses machine learning tree ensemble methods such as the cat boost regressor, light gradient boosting machine and extreme gradient boosting to predict the hourly solar radiation and load demand. Nine different hybrid metaheuristics are used to optimize the hybrid renewable energy system using forecasted data over 15 years, and the optimal sizing results are compared with those obtained from 1-year data simulation. The proposed approach leads to a more realistic hybrid renewable energy system capacity that satisfies all system constraints while being more reliable and environmentally friendly. The proposed framework provides a robust approach to optimizing hybrid renewable energy system sizing and performance evaluation that accounts for changing weather conditions over the lifespan of the system.

Knowing one's obesity group is very important for healthcare. Obesity can cause various diseases; however, BMI, which is the currently popular standard for judging obesity, does not accurately classify the obese group. This is because BMI just reflects height and weight, ignoring the characteristics of body type. Therefore, we present the idea that reflecting the three-dimensional (3D) measurements of the human body can better classify the obese group than BMI. To prove this, we recruited a total of 160 subjects and collected 3D body scans, Dual-energy X-ray absorptiometry (DXA), and Bioelectrical Impedance Analysis (BIA) data pairwise. Through this, 3D body scan data could be expanded clinically. We proposed a machine learning-based obesity classification framework using 3D body scan data, validated it through Accuracy, Recall, Precision, and F1 score, and compared it with BMI and BIA. BMI had the following values: Accuracy: 0.529, Recall: 0.472, Precision: 0.458, and F1 score: 0.462 while BIA had the following values: Accuracy: 0.752, Recall: 0.742, Precision: 0.751, and F1 score: 0.739. Our proposed model had the following values: Accuracy: 0.800, Recall: 0.767, Precision: 0.842, and F1 score: 0.792 and our accuracy was 80%, which is higher than either BMI at 52.9% or BIA at 75.2%. Our model can be used for obesity management through 3D body scans.

Global warming is one of the arch challenges of this era mainly caused by the increasing concentration of carbon dioxide in the atmosphere. Methanation process utilizes carbon dioxide and hydrogen to produce methane gas as an energy-rich fuel. To supply the hydrogen for the methanation process, LOHC could be used as a medium for long-range hydrogen transportation. However, the heat of reaction is needed to recover hydrogen from the LOHC medium. In this study, a new method to utilize the heat from the methanation process for dehydrogenation and optimum conditions are calculated for various LOHC materials. The new process designed uses an Air-Brayton cycle to generate the required high pressure as well as compensate for the LOHC dehydrogenation thermal energy requirement using a proportionate amount of methane produced. Also, the performance of various LOHC materials is compared in the proposed process. The simulation is performed via Aspen Plus® simulator. Dibenzyltoluene is found to be the best selection among the selected LOHC materials for use in this process with a system efficiency of 46.7% with a 100% medium recovery. Pyrrole group LOHC exhibits lower dehydrogenation temperature and energy requirement however are prone to bond scission and generally toxic. Toluene has high volatility resulting in its maximum recovery limited to 96.2% at an elevated pressure of 7 bar decreasing to 84.5% at 1 bar and 30 °C with a system efficiency of 49.08% and a low CVA of 36.74%, while NEC has 63.78% CVA with 55.64% efficiency and DBT has 54.12% CVA with 47.99% efficiency.

The development of alternate clean energy resources is among the most pressing issues in the energy sector in order to preserve the global natural environment. One of the ideal candidates is the utilization of hydrogen as a primary fuel in lieu of fossil fuels. It can be safely stored in liquid organic hydrogen carrier (LOHC) materials and recovered on demand. A uniform supply of hydrogen is essential for power production systems for their smooth operation. This study was conducted to determine the operating conditions of the dehydrogenation of perhydro-dibenzyltoluene (H18-DBT) to ensure that hydrogen supply in a continuous flow reactor remains stable over a wide range of temperatures. The hydrogen flow rate from the dehydrogenation reaction was measured and correlated with the degree of dehydrogenation (DoD) evaluated from the refractive index of reactant liquid samples at various temperatures, WHSV and the initial reactant concentrations. Moreover, a kinetic model is presented holding validity up to a WHSV of 67 h−1. The results acquired present a range for an order of reaction from 2.3 to 2.4 with the required activation energy of 171 kJ/mol.

O-linked-N-acetylglucosaminylation (O-GlcNAcylation) performed by O-GlcNAc transferase (OGT) is a nutrient-responsive post-translational modification (PTM) via the hexosamine biosynthetic pathway (HBP). Various transcription factors (TFs) are O-GlcNAcylated, affecting their activities and significantly contributing to cellular processes ranging from survival to cellular differentiation. Given the pleiotropic functions of O-GlcNAc modification, it has been studied in various fields, however, the role of O-GlcNAcylation during osteoclast differentiation remains to be explored. Kinetic transcriptome analysis during receptor activator of nuclear factor-kappaB (NF-κB) ligand (RANKL)-mediated osteoclast differentiation revealed that the nexus of major nutrient metabolism, HBP was critical for this process. We observed that the critical genes related to HBP activation, including Nagk, Gfpt1, and Ogt, were upregulated, while the global O-GlcNAcylation was increased concomitantly during osteoclast differentiation. The O-GlcNAcylation inhibition by the small-molecule inhibitor OSMI-1 reduced osteoclast differentiation in vitro and in vivo by disrupting the translocation of NF-κB p65 and nuclear factor of activated T cells c1 (NFATc1) into the nucleus by controlling their PTM O-GlcNAcylation. Furthermore, OSMI-1 had a synergistic effect with bone target therapy on osteoclastogenesis. Lastly, knocking down Ogt with shRNA (shOgt) mimicked OSMI-1’s effect on osteoclastogenesis. Targeting O-GlcNAcylation during osteoclast differentiation may be a valuable therapeutic approach for osteoclast-activated bone diseases.

The improvement of power transmission efficiency (PTE) is an important issue in the design of a wireless power transfer (WPT) system. The WPT system with multiple transmitting (Tx) or receiving (Rx) coils is a way to improve the PTE. This paper deals with the estimation of the mutual inductance angle for a two-dimensional (2D) WPT system with two Tx coils and one Rx coil. The mutual inductance angle is one of the most important parameters to determine the PTE in the 2D WPT system. The condition for the maximum PTE is investigated and the mutual inductance angle is defined for the 2D WPT system. An improved estimation method of the mutual inductance angle is proposed based on the phase-locked loop (PLL) technique using the voltages and currents of the Tx coils. The simulation and experimental results are provided to validate the effectiveness of the proposed method.

Purpose In this study, we developed a novel nitinol-actuated surgical instrument to conduct laparoscopic renal denervation for the treatment of resistant hypertension. We investigated whether shape and temperature settings of nitinol specimens fit well into the design goals. Furthermore, we conducted a pilot study to validate the mechanical and physiological performance of nerve ablation without damaging the renal artery. Method Tensile tests were performed to observe temperature-dependent thermomechanical properties and the original shape of nitinol specimens was set considering our design goal. We performed strain gage experiments to measure bending strain. We developed surgical instrument and operated laparoscopic renal denervation in a swine model. Subsequent impedance spectroscopy experiments were conducted to measure changes in impedance magnitudes during the operation and histological analyses were performed to visualize thermogenic damage to arteries and nerves. Results Tensile testing showed that the shape memory effect begins above 37 °C. Measured strains on nitinol surfaces were 2.10% ± 0.769%, below the strain limit of 8%. Impedance spectroscopy experiments showed decreases in magnitude in all six trials. After operation of laparoscopic renal denervation following the protocol, renal arteries and nerves were harvested and thermogenic damage was observed in nerves but not arteries. Conclusion We developed a novel nitinol-actuated surgical instrument with which to perform laparoscopic renal denervation. The feasibility of our device was verified using thermomechanical analyses of nitinol, and assessments of mechanical and physiological performance. Our device could be used in other laparoscopic procedures that require large degrees of freedom while restricting to trocar size.

[Purpose] The purpose of this study was to determine the effects of the flexion-distraction technique and drop technique on the straight leg raising angle and intervertebral disc height of patients with an intervertebral disc herniation. [Participants and Methods] Thirty patients with herniated intervertebral discs were divided into either an experimental group (n=15), who underwent flexion-distraction and drop techniques, or a control group (n=15), who obtained spinal decompression therapy. Both groups were treated three times per week for eight weeks. [Results] An intragroup comparison showed that the straight leg raising angle and the intervertebral disc height significantly increased in both groups. But it was not significantly difference in the intergroup comparison. [Conclusion] The flexion-distraction technique and the drop technique may serve as effective interventions for the straight leg raising angle and intervertebral disc height in patients with intervertebral disc herniations.

[Purpose] This study investigated the effects of manual manipulation therapy on the pain and dysfunction of patients with lumbar spinal stenosis. [Participants and Methods] In this study, 30 patients with chronic back pain were evenly divided into an experimental group, who received manual traction therapy, and a control group, who received intermittent traction therapy. Both groups received therapy three times a week for eight weeks. A visual analogue scale was used to measure participants' back pain, and the Oswestry disability index (ODI) was used to check the functional impediment they experienced as a result. [Results] The intragroup comparison showed that the visual analog scale and the ODI significantly decreased in the control group and the experimental group, respectively. The intergroup comparison after treatment showed that the visual analog scale and the ODI of the experimental group were significantly lower than in the control group. [Conclusion] The results of this study suggest that manual manipulation therapy is an effective intervention for treating pain and dysfunction in patients with lumbar spinal stenosis.

Trigeneration system offers an effective way to utilize the waste heat from the primary power generation unit and to produce refrigeration. This can be accomplished using adsorption chillers capable of producing chilled water above its freezing point. Experiments were carried out to measure the performance of the adsorption chiller as a standalone system as well in trigeneration system coupled with HT–PEMFC. Waste heat recovery of 2.76 kW was achieved from a 5 kW HT–PEMFC operating at full load condition using an adsorption chiller of 1.99–2.84 USTR refrigeration capacity increasing the full system efficiency from 32.0% to 39.8%. Waste heat recovery can be further improved by employing a common intermediate buffer tank heated via heat exchangers connected with multiple fuel cell systems supplying heat to a single high capacity adsorption chiller increasing the expected total system efficiency to 44.9%. Simulation of the adsorption chilling system was accomplished providing further insights of parameters affecting its performance as well as design criterion for heating and cooling requirements for a target refrigeration capacity of the adsorption chiller. The heating requirements were underestimated by 24% for a standalone system and 32% for trigeneration system primarily due to non-accountability of the gaseous adsorbate withheld within the adsorbent bed.

Information on the rheological characteristics of clathrate hydrate slurry is vital due to its diverse applications including hydrate slurry transportation as in seawater desalination by gas hydrate process, gas delivery through slurry pipelines, cold thermal energy storage, and secondary refrigeration by hydrate slurries. The current study experimentally investigated the rheological behavior of Tetrafluoroethane (Freon) hydrate slurry formed from R-134a and water serving as a medium for sea water desalination. Experiments were performed in a flow loop with a volume of 5.68 L and an inner pipe diameter of 21.5 mm, which was immersed in a constant temperature bath to maintain hydrate stable condition. Experiments were conducted with two phases in the loop; solid hydrate particles and liquid water. The hydrate solid volume fraction ranged from 15.8 to 31.7 vol%. Pressure drops along the straight section of the pipe were monitored while temperature, solid volume fraction and flow rate were kept const...

The Daeheung and Ryongyang magnesite deposits in the Dancheon Mineralized Belt (DMB) of South Hamgyong Province, North Korea, have attracted wide attention because of their large reserves and geological similarity with a number of magnesite deposits in the Dashiqiao magnesite belt of Liaoning Province, China. The study of the magnesite deposits in the DMB was performed to analyze and compare the genetic and geotectonic implications between the two districts. The Daeheung and Ryongyang deposits comprise sedimentary and metamorphic rocks of the Paleoproterozoic Bugdaecheon Series and intrusive and extrusive rocks of diverse ages. Magnesite ores comprise magnesite, talc, chlorite, quartz, calcite, and apatite, and based on the mineralogy, ores can be divided into four groups: pure magnesite, chlorite-magnesite, talc-magnesite, and chlorite-talc-magnesite. Rare earth element (REE) patterns can be classified into three types: middle REE-enriched, heavy REE-enriched, and light REE-enriched, implying multiple events in the formation of magnesite deposits in the DMB. The carbon and oxygen isotope compositions of magnesite ores and dolostones in the DMB range from −1.0 to 1.0‰ and from 8.7 to 23.0‰, respectively. The results suggest that the mineralization proceeded under low fluid/rock ratios at low XCO2 or large input of freshwater into hydrothermal fluids. Salinity and homogenization temperature of fluid inclusions in magnesites range from 0.5 to 34.1 wt% NaCl eq. and from 112 to 290 °C, respectively, which are similar to those of the Dashiqiao magnesite belt. Considering the ore mineralogy, REE patterns, stable isotope composition, and fluid inclusion characteristics, magnesite ores may have been formed by various processes involving the inflow of Mg-enriched brines into carbonate rocks and then hydrothermal fluid infiltration related to granitoid intrusions. These results indicate that the Daeheung and Ryongyang magnesite deposits in the DMB belong to the Veitsch-type sedimentary-metamorphic deposits and are genetically correlated with mineralization in the Dashiqiao magnesite belt of Liaoning Province in China.

[Purpose] The purpose of this study was to examine the effect of manual spinal traction therapy on the pain and Oswestry disability index of patients with chronic back pain. [Participants and Methods] In this study, 30 patients with chronic back pain were evenly divided into an experimental group 1, who received manual traction therapy, and an experimental group 2, who received intermittent traction therapy. Both groups received therapy three times a week for eight weeks. A visual analogue scale was used to measure participants' back pain, and the Oswestry disability index was used to check the functional impediment they experienced as a result. [Results] In a within-group comparison, visual analogue scale and Oswestry disability index significantly decreased in both the experimental 1 and experimental 2. In a between-group comparison after treatment, there was a significantly greater decrease in visual analogue scale and Oswestry disability index in the experimental group 1 compared to the experimental 2. [Conclusion] The manual spinal traction therapy was an effective intervention scheme for the treatment of pain and disorder in patients with chronic back pain.

Nucleotide pyrophosphatase/phosphodiesterase-1 (NPP1) inhibitors have been suggested as a potential treatment for calcium pyrophosphate dihydrate (CPPD) deposition disease. Here, we targeted the development of improved NPP1 inhibitors based on acyclic mimics of Pα,α-phosphorodithioate-substituted adenine nucleotides, 7-10. The latter were obtained in a facile two-step synthesis from adenine-(methoxy)ethanol. Among analogs 7-10, adenine-(methoxy)ethoxy-Pα,α-dithio-triphosphate, 8, was the most potent NPP1 inhibitor both with purified enzyme (IC50 0.645 μM) and in osteoarthritic human chondrocytes (IC50 0.033 μM). Furthermore, it efficaciously (10-fold vs. control) inhibited ATP-induced CPPD in human articular chondrocytes. Importantly, 8 was a highly selective NPP1 inhibitor which showed only minor inhibition of NPP3, CD39 and CD73, and did not inhibit TNAP (tissue nonspecific alkaline phosphatase) activity in human chondrocytes. Furthermore, 8 did not activate P2Y1,2,6 receptors. Analog 8 was not toxic to cultured chondrocytes at 100 μM. Therefore, 8 may be suitable for further development as a drug candidate for the treatment of CPPD arthritis and other NPP1-related diseases.