104 research outputs found
Assessment of Mechanical Problems for Centrifugal Pumps in Eastern Uttar Pradesh, India
Centrifugal pumps are vital property of the agriculture sector. A good quality pump can assure uninterrupted water supply to irrigate crops. The consumer of agriculture sector is largely illiterate and shortcoming of the pumps is faced by farmers in the terms of wastage of money. The study has carried out to grow awareness about the technique among the farmers. In such cases reliable functioning of the pump is an absolute necessity. The major objective of this paper is the analysis of the component life and frequency of occurrence of problem in a centrifugal pump. A survey was conducted among the farmers of tube well irrigated areas and subsequently analyzed. It was found that frequency of occurrence of leakage and excessive noise are 3.17 and 3.11 years which is the most frequent shortcoming found under study. It was also found that the mean life of centrifugal pump components i.e. Bearing, Packing, Impeller, shaft and casing was found as 3.56 , 3.18 , 3.61, 4.20 and 4.64 years respectively. The package of seal has longest life for the operation of centrifugal pump. For the frequency of occurrence of these problems, four the category scale has also chosen. Value 1 refers to always occurs, 2 most frequent occurs, 3 occasionally occurs, 4 – rarely occurs. Under the study a centrifugal pump for irrigating crop has treated as vital input, which is also a key factor in boosting productivity, for the national development and food security
Role of Macrophages in Solid Tumor Metabolism
Cancer cells undergo several complex processes to grow and evolve. For their survival, they manipulate the entire system and acquire the ability to gain all the energy demands from the host system itself. Tumor associated macrophages (TAMs) are macrophages abundantly present in the tumor micro environment (TME) and essentially plays a critical role in coordination with the tumor cells helping them to progress and metastasize. One of the key hallmarks in tumor cells is elevated metabolic processes such as glycolysis, fatty acid oxidation, mitochondrial oxidation, and amino acid metabolism. Macrophages help cancer cells to achieve this metabolic demand through a series of signaling events including mTOR, Akt, and PI3K pathways. The M2-like phenotype of macrophages leads to the tumorous macrophage phenotype along with the tumor cells to support tumor growth through metabolic dysregulation. Focusing upon the area of macrophage-mediated tumor metabolism in solid tumors has been a new area that provides new effective targets to treat cancer. This chapter discusses the role of macrophages in tumor metabolism and cancer progression. Targeting TAMs in tumor microenvironment through metabolic axis could be a potential therapeutic option to control the solid tumor growth and propagation
Novel formulation for co-delivery of cinnamon- and cumin-loaded polymeric nanoparticles to enhance their oral bioavailability
Nanobiotechnology has been an encouraging approach to improving the efficacy of hydrophobic bioactive compounds. The biologically active constituents present in herbal extracts are poorly absorbed, resulting in loss of bioavailability and efficacy. Hence, herbal medicine and nanotechnology are combined to overcome these limitations. The surface-to-volume ratio of nanoparticles is high and as the size is small, the functional properties are enhanced. The present study reports the synthesis of cinnamon and cumin (Ci–Cu) dual drug-loaded poly (D, L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) to overcome the limitations of oral bioavailability and extend the effect of these drugs for alleviating health problems. The solvent evaporation method was adopted for the synthesis, and the as-prepared nanoparticles were characterized by Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, Transmission electron microscopy (TEM) and X-ray diffraction (XRD). The average size of the formed spherical Ci-Cu nanoparticles ranged between 90 and 120 nm. The encapsulation efficiency of the drug was found to be 79% ± 4.5%. XRD analysis demonstrated that cinnamon and cumin were amorphously scattered in the PLGA matrix. The FTIR bands showed no evident changes suggesting the no direct molecular interactions between the drug and the polymer. At pH 6.9, the release studies in vitro exhibited a burst initially followed by a tendency to obtain a slower steady release. The results indicated that the Cu-Ci dual drug-loaded polymeric NPs has drug release at a slower rate. The time taken for 25% release of drug in Ci-Cu-loaded PLGA NPs was twice as compared to cumin-loaded PLGA Nps, and three times compared to cinnamon-loaded PLGA NPs.Open Access funding provided by the Qatar National Library. This study was funded by the Qatar University, Kishor Kumar Sadasivuni Grant no: QUCG-CAM-21/22-1.Scopu
Biometric Assessment of Temporomandibular Disorders in Orthodontics: A Multi-arm Randomized Controlled Trial
Objective:This randomized controlled trial aimed to evaluate the role of fixed orthodontic treatment in the aggravation, precipitation, or alleviation of temporomandibular disorders in young adults.Methods:Sixty patients were randomly assigned to 4 groups of 15 patients each (group I, orthodontic treatment in temporomandibular disorder-free orthodontic patients; group II, orthodontic treatment in patients with mild symptoms of temporomandibular disorders; group III, splint therapy accompanied by orthodontic treatment in patients with moderate symptoms; and group IV, control with no treatment). The biometric equipment used were the T-scan, to analyze the occlusal component; the BioEMG for muscular analysis; BioJVA for temporomandibular joint acoustic analysis; and JT3D for mandibular kinematic analysis. The paired t-test and ANOVA were used for intragroup and intergroup comparisons, respectively. The difference between groups was assessed using post hoc Tukey’s test.Results:Groups I and III showed significant difference in the occlusal, muscular, temporomandibular joint vibration, and kinematic mandibular assessment variables. Group II showed significant improvement in occlusal variables only. Group IV did not show improvement in any of the variables except for certain muscular components.Conclusion:Successful practical utilization of biometric equipment revealed that fixed orthodontic treatment does not aggravate temporomandibular disorders. It was also found that temporomandibular disorders due to malocclusion can be treated successfully with orthodontic treatment, whereas temporomandibular disorders due to multifactorial temporomandibular joint and muscular components might require splint therapy before orthodontic intervention
A Smart Colorimetric Platform for Detection of Methanol, Ethanol and Formic Acid
Carbon dioxide (CO2 ) is a greenhouse gas in the atmosphere and scientists are working on converting it to useful products, thereby reducing its quantity in the atmosphere. For converting CO2, different approaches are used, and among them, electrochemistry is found to be the most common and more efficient technique. Current methods for detecting the products of electrochemical CO2 conversion are time-consuming and complex. To combat this, a simple, cost-effective colorimetric method has been developed to detect methanol, ethanol, and formic acid, which are formed electrochemically from CO2 . In the present work, the highly efficient sensitive dyes were successfully established to detect these three compounds under optimized conditions. These dyes demonstrated excellent selectivity and showed no cross-reaction with other products generated in the CO2 conversion system. In the analysis using these three compounds, this strategy shows good specificity and limit of detection (LOD, ~0.03-0.06 ppm). A cost-effective and sensitive Internet of Things (IoT) colorimetric sensor prototype was developed to implement these dyes systems for practical and real-time application. Employing the dyes as sensing elements, the prototype exhibits unique red, green, and blue (RGB) values upon exposure to test solutions with a short response time of 2 s. Detection of these compounds via this new approach has been proven effective by comparing them with nuclear magnetic resonance (NMR). This novel approach can replace heavy-duty instruments such as high-pressure liquid chromatography (HPLC), gas chromatography (G.C.), and NMR due to its extraordinary selectivity and rapidity.Funding: This research was funded by Qatar National Research Fund (a member of the Qatar Foundation) grant number NPRP11S-1221-170116 and the APC was funded by Qatar National Research Fund.Scopu
Comparison study of metal oxides (CeO2, CuO, SnO2, CdO, ZnO and TiO2) decked few layered graphene nanocomposites for Dye-Sensitized solar cells
Recent research is focused on few layered graphene (FLG) with various metal oxides (MOs) as (MOs; CeO2, CuO, SnO2, CdO, ZnO, and TiO2) nanocomposite materials are alternatives to critically important in the fabrication of solar cell devices. In this work, FLG with different MOs nanocomposites were prepared by a novel eco-friendly viable ultrasonic assisted route (UAR). The prepared FLG/MO nanocomposites were performed with various characterization techniques. The crystal and phase compositional were carried out through using X-ray diffraction technique. Surface morphological studies by field emission scanning electron microscope (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM). Spectroscopic methods were done by Raman and UV-Vis Diffuse reflectance spectra (UV-DRS). The prepared FLG/MO nanocomposites materials were used as a photoanode, in the fabrication of dye sensitized solar cells (DSSCs). Compared to TiO2 nanoparticles (NPs) and other FLG/MO nanocomposites, FLG/TiO2 nanocomposites exhibited superior photovoltaic properties. The ob-tained results indicate that FLG/TiO2 nanocomposites significantly improved the power conversion efficiency (PCE) of DSSCs. The photovoltaic analyses were performed in a solar simulator with an air mass (AM) of 1.5 G, power density of 100 m W/m2, and current density-voltage (J-V) was investigated using N719 dye.Funding: ?This research was funded by QATAR NATIONAL RESEARCH FUND (QNRF), grant number NPRP: 12S-0131-190030? and ?The APC was funded by QATAR NATIONAL RE-SEARCH FUND (QNRF)?.Scopu
Improvement of heat sink performance using paraffin/graphite/hydrogel phase change composite coating
Phase-change materials offer high latent heat and are widely used for energy storage applications. Paraffin wax is usually used as a phase-change material. However, its application in energy storage is restricted due to its low thermal conductivity. In the present work, graphite and graphite-hydrogel are used to enhance the thermal conductivity and heat release properties of paraffin wax. Wax-graphite (W-G) and wax-graphite-hydrogel (W-G-H) composites were synthesized by the dispersion of graphite and graphite-hydrogel in paraffin wax above its melting temperature. Scanning electron microscope (SEM) analysis was used to investigate the graphite and graphite-hydrogel distribution in the paraffin wax matrix. Thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) characterization were performed to measure the thermal stability and phase transition properties, respectively. DSC revealed that all composites have a similar melting temperature. The W-G-H composite displayed nearly 12 folds more thermal conductivity compared to the pure paraffin wax. High temperature brings adverse impacts on energy efficiency, and even destroys a semiconductor device. The synthesized W-G-H composite is proposed to decrease the working temperature of semiconductor devices. As an applicative demonstration, the W-G-H composite film was coated at the back of the solar panel. The W-G-H composite coated solar panel displayed a surface temperature that was near ∼4 °C lower than the bare solar panel while operating. The real-time experiment indicates that the W-G-H composite has high thermal conductivity and heat release properties. The study reports fundamentally new low-cost, simple, scalable, and self-adaptive, passive cooling technology to the semiconductor industry. The proposed material can further be developed in the form of paint and its heat sink properties can be improved by introducing hydrogels doped with Li+ and Br− ions.This work was supported by Qatar National Research Fund under the grant no. NPRP12S-0131-190030 . Open Access funding was provided by the Qatar National Librar
High-Precision Nonenzymatic Electrochemical Glucose Sensing Based on CNTs/CuO Nanocomposite
The measurement of blood glucose levels is essential for diagnosing and managing diabetes. Enzymatic and nonenzymatic approaches using electrochemical biosensors are used to measure serum or plasma glucose accurately. Current research aims to develop and improve noninvasive methods of detecting glucose in sweat that are accurate, sensitive, and stable. The carbon nanotube (CNT)-copper oxide (CuO) nanocomposite (NC) improved direct electron transport to the electrode surface in this study. The complex precipitation method was used to make this NC. X-ray diffraction (XRD) and scanning electron microscopy were used to investigate the crystal structure and morphology of the prepared catalyst. Using cyclic voltammetry and amperometry, the electrocatalytic activity of the as-prepared catalyst was evaluated. The electrocatalytic activity in artificial sweat solution was examined at various scan rates and at various glucose concentrations. The detection limit of the CNT-CuO NC catalyst was 3.90 µM, with a sensitivity of 15.3 mA cm−2 µM−1 in a linear range of 5–100 µM. Furthermore, this NC demonstrated a high degree of selectivity for various bio-compounds found in sweat, with no interfering cross-reactions from these species. The CNT-CuO NC, as produced, has good sensitivity, rapid reaction time (2 s), and stability, indicating its potential for glucose sensing.This publication was supported by Qatar University internal (Grant No. QUCG-CAM-21/22-1). The findings herein are solely the responsibility of the authors.Scopu
Exploring state-of-the-art advances in targeted nanomedicines for managing acute and chronic inflammatory lung diseases
Diagnosis and treatment of lung diseases pose serious challenges. Currently, diagnostic as well as therapeutic methods show poor efficacy toward drug-resistant bacterial infections, while chemotherapy causes toxicity and nonspecific delivery of drugs. Advanced treatment methods that cure lung-related diseases, by enabling drug bioavailability via nasal passages during mucosal formation, which interferes with drug penetration to targeted sites, are in demand. Nanotechnology confers several advantages. Currently, different nanoparticles, or their combinations, are being used to enhance targeted drug delivery. Nanomedicine, a combination of nanoparticles and therapeutic agents, that delivers drugs to targeted sites increases the bioavailability of drugs at these sites. Thus, nanotechnology is superior to conventional chemotherapeutic strategies. Here, the authors review the latest advancements in nanomedicine-based drug-delivery methods for managing acute and chronic inflammatory lung diseases
A Novel Design and Development of Multilevel Inverters for Parallel Operated PMSG-Based Standalone Wind Energy Conversion Systems
The article presents the new power conversion for parallel-operated wind energy conversion systems. It has been formulated by new multilevel inverter (MLI) topologies with reduced switch counts, lowered conduction losses and a very good output voltage spectrum. The wind energy conversion systems included permanent magnet synchronous generator (PMSG), a diode bridge rectifier, a conventional boost converter and a novel multilevel inverter connected to an isolated load. The power conversion utilizing a novel multilevel DC to AC converter has been proven for its better efficiency, voltage utilization and power quality. The integration of wind energy conversion systems has been explored in MATLAB Simulink, and the hardware setup does the authentication of the MLI structure.This work was supported by Qatar National Research Fund under the grant no. MME03-1226-210042. The statements made herein are solely the responsibility of the authors.Scopu
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