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Abstract Microchannel heat exchangers are heat exchangers with a tube diameter of less than 1 mm. Conventional cooling approaches such as the forced‐air cooling technique fail in high technological compact systems because of the small‐sized surfaces of chips and circuits. In comparison, microchannel heat exchangers are being extensively utilized in compact‐sized devices where a high heat‐transfer medium is required. Moreover, consumers' continued desire for compact products has prompted researchers to study microchannel heat exchangers for their ability to boost the rate of heat transfer that ensures the safety of compact designs. This study presents the evaluation of performance parameters and the manufacturing aspects of microchannel heat exchangers. This study also examines how microchannel heat exchangers are affected by several parameters, including the type of working fluid used, Brownian motion, geometry of the channel, Reynolds number, Nusselt number, Knudsen number, wall resistance of the channel, the effect of gravity, and inlet and outlet arrangement for fluid. Investigating the various geometries for the microchannel indicates that the least pressure drop occurs in square shape cross‐section channels while the highest pressure drop occurs in channels with triangular cross‐sections. Moreover, it has been observed that, with the addition of nanoparticles to the working fluid, the thermal properties of the exchangers as well as the pressure drop increases while at the same time it reduces the boundary layer thickness. In addition, the Reynolds number affects the performance irrespective of the channel geometry. When the fluid is added with nanoparticles, like, Al2O3 and copper oxide (CuO) with different volumetric fractions (φ) of 0%, 0.5%, 1%, 1.5%, and 2%, the performance of the microchannel rises with rising the Reynolds number but conversely when the fluid is used in pure form the performance decreases with the rising value of Reynolds number. In addition, it has been observed that the overall improvement is obtained at φ = 2% and Re = 100 for CuO–water nanofluid. Apart from this, the least heat transfer is recorded at φ = 0.5% and Re = 1.00 for both nanofluids. Moreover, this study concludes that the Nusselt number is independent of the Reynolds number in the regime of laminar flow. It is further evident that as the nanoparticle size reduces, the Nusselt number rises when all the remaining conditions are the same. Apart from this, investigating the inlet/outlet arrangement through finite volume method for D‐, I‐, N‐, S‐, U‐, and V‐type arrangements, it is evident that the V‐type sink has overall greater performance. In terms of gravity, it is observed that it has no effect on the performance of microchannel heat exchangers. This study further illustrates the effects of the fabrication method on the performance of the microchannel heat exchangers.

The current study explores the prospective of a nitrogen-doped graphene (NG) incorporated into ZnSe-TiO2 composites via hydrothermal method for supercapacitor electrodes. Structural, morphological, and electronic characterizations are conducted using XRD, SEM, Raman, and UV analyses. The electrochemical study is performed and galvanostatic charge-discharge (GCD) and cyclic voltammetry (CV) are evaluated for the supercapacitor electrode material. Results demonstrate improved performance in the ZnSe-NG-TiO2 composite, indicating its potential for advanced supercapacitors with enhanced efficiency, stability, and power density. Specific capacity calculations and galvanic charge-discharge experiments confirmed the promising electrochemical activity of ZnSe-NG-TiO2, which has a specific capacity of 222 C/g. The negative link among specific capacity and current density demonstrated the composite’s potential for high energy density and high-power density electrochemical devices. Overall, the study shows that composite materials derived from multiple families can synergistically improve electrode characteristics for advanced energy storage applications.

In this study, Chenopodium murale Linn. extracts have been evaluated for its in vitro antioxidant, enzyme inhibition, and in vivo neuropharmacological properties in streptozotocin (STZ)-induced memory impairment in rat model. First, the plant was subjected to extraction and fractionation, then quantitative phytochemical analysis was performed to estimate the major phytochemical groups in the extract where high amounts of phenolics and saponins were detected in crude and chloroform extract. The highest total phenolic contents, total flavonoid contents, and total tannin content were also recorded in crude extract and chloroform fraction. The in vitro antioxidant potential of chloroform fraction was high with IC50 value of 41.78 and 67.33 μg/mL against DPPH and ABTS radicals, respectively, followed by ethyl acetate fraction. The chloroform fraction (ChMu-Chf) also exhibited potent activity against glucosidase with IC50 of 89.72 ± 0.88 μg/mL followed by ethyl acetate extract (ChMu-Et; IC50 of 140.20 ± 0.98 μg/mL). ChMu-Chf again exhibited potent activity against acetylcholinesterase (AChE) with IC50 of 68.91 ± 0.87 μg/mL followed by ChMu-Et with IC50 of 78.57 ± 0.95 μg/mL. In vivo memory impairment was assessed using the novel object discrimination task, Y-maze, and passive avoidance task. Ex vivo antioxidant enzyme activities and oxidative stress markers like catalase, superoxide dismutase (SOD), malondialdehyde, and glutathione were quantified, and the AChE activity was also determined in the rat brain. No significant differences were observed amongst all the groups treated with crude, chloroform, and ethyl acetate in comparison with positive control donepezil group in connection to initial latency; whereas, the STZ diabetic group displayed a significant fall in recall and retention capability. The blood glucose level was more potently lowered by chloroform extract. The crude extract also increased the SOD level significantly in the brain of the treated rat by 8.01 ± 0.51 and 8.19 ± 0.39 units/mg at 100 and 200 mg/kg body weight (P < 0.01, n = 6), whereas the chloroform extract increased the SOD level to 9.41 ± 0.40 and 9.72 ± 0.51 units/mg, respectively, at 75 and 150 mg/kg body weight as compared to STZ group. The acetylcholine level was also elevated to greater extent by chloroform fraction that might contain a potential inhibitor of acetylcholinesterase. Treatment with C. murale ameliorated cognitive dysfunction in behavioral study, and provided significant defense from neuronal oxidative stress in the brain of the STZ-induced diabetic rats. Thus C. murale Linn. could be an inspiring plant resource that needs to be further investigated for isolation of potential compounds in pure form and their evaluation as a potent neuropharmacological drug.

The purpose of this research is to investigate the impact of moisture content, closing speed, and pressurizing speed of hot press on the density, uniformity of density distribution, and properties of Medium Density Fiberboard (MDF) products. Moisture content affects the plasticity, heat conductivity, and hydrolysis reaction of the fiber and appropriate moisture content ensures the quality of the board. Excessive moisture content can lead to defects such as pollution and bubbles on the surface of the board. Closing time and pressurizing speed affect the nature, quality, and section structure of the MDF. The section density of the board varies with the closing time, and the product properties, especially the strength differs largely. The pressurizing speed influences the density distribution and board properties. Fast pressurizing speed results in high Modulus of Rupture (MoR) and low Internal Bonding (IB), while slow pressurizing speed leads to low MoR and high IB. Pre-plasticizing layer can improve the quality of MDF by increasing the density and hardness of the board surface. The findings provide guidance for optimizing the MDF production process and improving the quality of MDF products. Applying a fast pressurizing speed during the manufacturing process of MDF has resulted in a 15.7% increase in the MoR, which is a measure of the material’s ability to withstand stress before breaking as compared to using a slow pressurizing speed. Additionally, using a fast pressurizing speed has led to a reduction of 17.4% in the IB, which is a measure of the ability of the board to resist internal separation or delamination. Therefore, a fast pressurizing speed is more effective in improving the mechanical properties of MDF.

Background: In general practice, venous ulcers (stasis ulcers) are the most common and recurrent leg ulcers. Ignorance of it can have a severe detrimental effect on one's quality of life, cause gangrene, and even the limb amputation. Venous ulcers are the most dangerous and disabling side effect of chronic venous insufficiency. Leech therapy seems to be effective for the treatment of varicose ulcers due to its salivary secretions which it injects during bloodsucking. The saliva of leeches contains certain biochemical with vaso-dilating, anticoagulant, anesthetic, thrombolytic, antibiotic, analgesic, and anti-inflammatory properties. As a result, Irsal-e-Alaq (Hirudotherapy), one of the Unani regimens, can effectively control it. Objective: The purpose of this case report is to provide insight into the effects of Irsal-e-Alaq (Hirudotherapy) on venous ulcers. Intervention: A 60-year-old male has a complaintof ulceration in his left lower leg near the medial malleolus with swelling, pain, discharge, and darkening of the skin of the left lower limb. Four leeches were applied once every week for 2 months. Efficacy of leech therapy was assessed on every 15th day by pain /leg discomfort on 4 point scale ranging from 0-3, limb girth at calf, ankle & foot, pigmentation color on 4 point scale, pigmentation area, pain in ulcer on 4 point scale from 0-3, ulcer depth, PUSH Score. Hb% was assessed every 15th day to check anemia, colour flow Doppler was done to assess any change in vein anatomy. Result: In this case report, the ulcers were completely healed, and also showed remarkable improvement in other variables. Conclusion: Irsal-e-Alaq has been proven beneficial in treating venous ulcers and enhancing patient’s quality of life. [ABSTRACT FROM AUTHOR]

Background: This randomized clinical and haematological study evaluated the effect of Hijama-BilShart (Wet Cupping) on musculoskeletal pain and inflammatory markers in venous and cupped blood. Materials and Methods: 110 patients with musculoskeletal pain were screened, with 90 diagnosed and included. After 30 subjects were lost to follow-up, 60 completed the study. Participants received 4 weekly sessions of wet cupping therapy over 4 weeks. Pain intensity was measured using VAS and KOOS scores, and inflammatory markers (Serum uric acid & CRP) were assessed in venous and cupped blood. Results: Pain relief, measured by VAS, showed significant improvement across various musculoskeletal conditions: cervical spondylosis, frozen shoulder, low backache, sciatic pain, knee osteoarthritis, gout, and rheumatoid arthritis. KOOS scores for knee osteoarthritis improved significantly. Serum uric acid levels in venous blood were suggestively insignificant, while CRP levels decreased gradually but were not statistically significant. No adverse effects were reported. Conclusion: Hijama-Bil-Shart (wet cupping) therapy is effective in relieving musculoskeletal pain and improving quality of life. It shows long-term benefits with sustained pain relief and gradual reduction in CRP levels. However, it is not effective in significantly reducing raised serum uric acid levels. [ABSTRACT FROM AUTHOR]

Full thickness endoscopic resection of large submucosal gastric tumors (>3 cm) is a big challenge for endoscopists. Issues include how to efficiently resect the lesion, obtain homeostasis, and suture the defect. There are no guidelines regarding the importance of patient position on the success of endoscopic resections in anesthetized patients. Typically, the patient is placed in left lateral position for the endoscopic therapy and during the procedure patient’s position is changed to maintain the tumor above the gastric fluids to prevent gastric juices and tumor or tumor fragments from falling into the peritoneal cavity in the event of perforation. This study emphasized the importance of planning the procedure to ensure that the patient’s position and anesthetist’s concerns are met and allow optimal access to the lesion for endoscopic resection. Prior to sedation the patient should be positioned so that the tumor is in the up position which also prevents blood obscuring the operative field, helps detect bleeding points for immediately hemostasis. In addition, due to gravitational effect, the resected tumor will fall into the gastric cavity exposing the root of the tumor making resection easier and reduce procedure time. Preplanning avoids unnecessary readjustment of positioning and improves the ease and safety of the procedure.

Gastrointestinal stromal tumors are common gastrointestinal tumors typically originating from the muscularis propria layer of the stomach. Small gastric stromal tumors are usually detected incidentally during routine endoscopic examination. Although they may have malignant potentially, controversies remain regarding the need for endoscopic resection of small gastric stromal tumors originating from the muscularis propria. According to the guidelines of the European Society of Medical Oncology, all gastrointestinal stromal tumors >2 cm in size should be resected with endoscopic surveillance recommended for tumors

Background: Since ancient times, Unani physicians have controlled certain illnesses by altering the metabolic process using a variety of therapeutic approaches. Some treatment tenets have been promoted by Ibne-sina (Avicenna). Regimenal therapy is a fundamental approach to treatment that aims to eradicate sick matter, control excessive production, control its spread, and resolve it by specialised approaches, ultimately restoring humoral equilibrium. Hijama (Cupping) is one such operation. The Arabic word "Hijamat" (from the phrase "Hajm") means "volume", but it is also used to refer to sucking. Additionally, it might indicate "to minimise", "to return to basic size", or "to reduce the volume". One of the most prevalent symptoms of Irq-al-nasa (Sciatica) is lower limb neuralgic pain. This illness has the potential to become persistent and chronic, with significant socioeconomic consequences. Its overall incidence is estimated to be between 13% and 40%. Objective: Mainstream therapists primarily treat Sciatica with medication, surgery, or occasionally both. There should be an efficient substitute for evidence-based medicine because of its negative impacts, high cost, and diseasecentric approach to treatment. Extensive research has been conducted to investigate the potential benefits of this traditional treatment plan for the management of Sciatica. [ABSTRACT FROM AUTHOR]

Background: Prediabetes is a metabolic condition characterized by blood glucose levels higher than normal but below the threshold for diabetes mellitus. It represents a critical stage in the progression towards type 2 diabetes mellitus (T2DM) and is associated with an increased risk of cardiovascular disease and other complications. The two major pathophysiologic defects responsible for losing glucose tolerance are insulin resistance and β-cell glucose insensitivity, both appearing in subjects of Intermediate Hyperglycaemia. In classical literature, Unani physicians have described the initial symptoms and factors leading to the pathology, the risk factors are described in terms of ‘Su-e-mizaj’ as per the concept of Tibb. So, it is considered in the context of Ziabetus which is described as a disease that develops due to Sue-mizaj haar (abnormal hot temperament). The symptoms mentioned in Unani medicine are increased frequency of micturition (ants and flies are attracted to urine), increased thirst, nocturia, dryness of mouth and whole body, fatigue, loss of weight, malaise, and cramps in lower extremities. The modern drug-based approach for the management of Intermediate Hyperglycaemia is associated with inherent drawbacks, including toxicity, tolerability, cost, and efficacy.Objective: The purpose of this review is to provide an in-depth understanding of prediabetes concerning the classical literature of Greek medicine based on the analysis of certain parameters like etiopathophysiology, current diagnostic criteria, risk factors, and evidence-based management strategies. By synthesizing findings from epidemiological studies, and clinical trials, this paper aims to enhance understanding of prediabetes and facilitate effective preventive measures and interventions [ABSTRACT FROM AUTHOR]

We present a carbonation-assisted flotation method for nickel (Ni) separation from low-grade ultramafic ores. The high process economics of conventional flotation of low-grade ultramafic ores makes Ni unrecoverable on an industrial scale. Based on the fundamentals of CO2 sequestration in minerals, we carbonated a low-grade serpentine (lizardite) ore specimen under extreme conditions (185 °C, 15 MPa, and 24 h) and attained a conversion efficiency of serpentine to magnesite of 22% and 16% in the presence and absence of inorganic salts, respectively. Rhombohedral structures on carbonated particles detected using scanning electron microscopy suggested the formation of magnesite. We also found that Ni–Fe existed as sulfides, as confirmed by elemental mapping micrographs, and did not leach out as Ni2+ and Fe2+, as confirmed through carbonation supernatant analysis. Here, we introduced Denver cell froth flotation experiments after carbonation, which showed that the carbonated ore in the presence of inorganic salts had 29% higher Ni recovery and 0.15 wt% higher nickel grade than the uncarbonated ore. This study is the first to successfully show that the carbonation of serpentine containing nickel-bearing pentlandite leads to magnesite formation, does not lead to the dissolution of nickel sulphide, and enhances the nickel separation efficiency during froth flotation. This study paves the path forward for the integration of mineral carbonation in the processing of low-grade ultramafic nickel ores. [ABSTRACT FROM AUTHOR]

Abstract Background Implementation of a mandatory insurance scheme depends on several issues, and among them are regulation, management, and program design which are very crucial. Sometimes a well-designed insurance scheme cannot attract an adequate number of people toward the scheme. Therefore, this study is aimed to explore the implementation challenges of Sajida Foundation’s health insurance scheme. Methods An exploratory qualitative research design has been applied to explore the challenges that normally exist in regular implementation process. The study population was both field and official level employees who are directly involved in the implementation process of Nirapotta scheme in Karanigoni branch. Results Successful implementation of the health insurance scheme of Sajida Foundation is getting constraints by several factors, and among them are lack of dedicated staff for this program, less involvement with community people, inadequate program knowledge dissemination to the people, and not providing incentive for work of Nirapotta are considered as the major challenges of implementation of Nirapotta Scheme. Challenges faced by policy-makers include incoordination with Microfinance Regulatory Authority and not having the latest software for perfect monitoring and evaluation of the Nirapotta program. Apart from this, there are some challenges in implementation which are normally faced in program; some of the most noteworthy findings are incoordination between employees especially in branch level, transient position of Sajida bondhu in the Nirapotta program, and low payment scale compared to other organizations. Conclusions Implementation of Nirapotta scheme is getting constraints by multiple factors which can easily be overcome by involving all necessary stakeholders and taking their valuable concern for further development of the scheme to ensure long-term sustainability of the program.

Renal transplantation is the treatment of choice for improved survival and quality of life in patients with end-stage renal disease. However, perirenal fluid collections are common surgical complications after renal transplant, with about 0.6 to 18% of patients developing a lymphocele. Conventional treatments include percutaneous aspiration and drainage, laparoscopic fenestration, and open surgical decompression stepwise. Recently, a new image-guided percutaneous transperitoneal balloon fenestration technique has been described as an alternative to the laparoscopic or surgical technique. We present the case of a 25-year-old male patient diagnosed with a lymphocele after 2 months of transplantation and no resolution of the lymphocele with percutaneous aspiration and drainage. We used this new technique under ultrasound and fluoroscopy guidance, which resulted in the resolution of the lymphocele at 1 month postprocedure. This case report highlights this new technique's potential role in successfully managing the posttransplant lymphocele in a minimally invasive manner. [ABSTRACT FROM AUTHOR]