275 research outputs found
Effect of Nozzle Divergence Angle on Plume Expansion In Outer-Space Conditions
We carry out numerical simulations to investigate
the effect of nozzle divergence angle on back flow of
plume expansion into rarefied atmosphere.
Results are
obtained using open source compressible computational
fluid dynamics (CFD) solver.
Non-equilibrium slip and
jump boundary conditions for velocity and temperature are
implemented to capture rarefaction rarefaction effects in
the slip flow regime. The solver has been validated with
the experimental data for a nozzle flow in the slip flow
regime. We explore the non-linear non-equilibrium gas flow
physics of a supersonic jet expansion. We report results of
pressure, heat and drag coefficients for different divergent
angles (
12
0
,
15
0
and
20
0
) at 80 km altitude conditions. The
slip based results for heat loads significantly under-predict
the no-slip ones, while for pressure and drag coefficients,
deviations are found to be minute. It is noticed that thrust
coefficient of nozzle increases with increase in divergence
angle, however, nozzle with divergent angle of
15
0
led to
minimum drag and heat transfer load on the critical region.
The current study is important from the perspective of the
overall aero-thermodynamic design of a typical supersonic rocket model operating under rarefied conditions
Heterogeneous Fenton catalysts: A review of recent advances /
Hosted in Science DirectHeterogeneous Fenton catalysts are emerging as excellent materials for applications related to water purification. In this review, recent trends in the synthesis and application of heterogeneous Fenton catalysts for the abatement of organic pollutants and disinfection of microorganisms are discussed. It is noted that as the complexity of cell wall increases, the resistance level towards various disinfectants increases and it requires either harsh conditions or longer exposure time for the complete disinfection. In case of viruses, enveloped viruses (e.g. SARS-CoV-2) are found to be more susceptible to disinfectants than the non-enveloped viruses. The
introduction of plasmonic materials with the Fenton catalysts broadens the visible light absorption efficiency of the hybrid material, and incorporation of semiconductor material improves the rate of regeneration of Fe(II) from Fe(III). A special emphasis is given to the use of Fenton catalysts for antibacterial applications. Composite materials of magnetite and ferrites remain a champion in this area because of their easy separation and reuse, owing to their magnetic properties. Iron minerals supported on clay materials, perovskites, carbon materials, zeolites and metal-organic frameworks (MOFs) dramatically increase the catalytic degradation
rate of contaminants by providing high surface area, good mechanical stability, and improved electron transfer. Moreover, insights to the zero-valent iron and its capacity to remove a wide range of organic pollutants, heavy metals and bacterial contamination are also discussed. Real world applications and the role of natural organic matter are summarised. Parameter optimisation (e.g. light source, dosage of catalyst, concentration of H2O2 etc.), sustainable models for the reusability or recyclability of the catalyst and the theoretical understanding and mechanistic aspects of the photo-Fenton process are also explained. Additionally, this review
summarises the opportunities and future directions of research in the heterogeneous Fenton catalysis.ye
Protective Effects of Lemna minor Linn. On Hepatic and Cognitive Impairments in Acetaminophen Induced Hepatic Encephalopathy in Rats
Aim: Lemna minor Linn., an aquatic plant, is a promising novel therapeutic agent that has been traditionally used in ethnobotanical practices as an ecofriendly supplement for the management of various ailments. This study involves the evaluation of ethanolic extract of Lemna minor Linn. against Paracetamol-induced Hepatic Encephalopathy using in vitro and in vivo Models.
Methods: The acute oral toxicity study of the ethanolic extract of Lemna minor (EELM) was conducted following the OECD-425 guidelines over a 14-day period. A total of nine animals were used for this toxicity assessment. The EELM was tested in Paracetamol(PCM)-induced bioactivation animal model at two different dosages 200 and in comparison with silymarin as a standard compound. The In vivo experimental study was conducted using Sprague Dawley rats which was divided into 5 groups each group containing 6 animals so the total no of animals used in the study was 30 animals. The treatment groups included: normal control ( ), 100mg/kg silymarin (standard) and the EELM of two different doses of 200 and , p.o were administered to rats 10 hr before paracetamol ( ) treatment. Rats were orally administered their respective doses every day for total 30days. Paracetamol-induced oxidative liver damage disrupted normal levels of liver enzymes, total protein, and bilirubin, while also depleting antioxidant reserves. This oxidative stress was strongly associated with paracetamol toxicity, leading to a marked depletion of glutathione (GSH) and impairing both memory and cognitive function in the animals. Behavioral parameters are performed to evaluate the effect of drugs on cognitive behaviour of animals. Morris water maze test was performed to study how animals learn and remembers the spatial information relying on distal cues to locate the hidden platform in an opaque water.
Additionally, elevated plus maze was performed to measures the anxious behaviour of rats, the criterion was tested based on the conflict between rats innate instincts to explore new environment and avoid open, well-lit areas. The potential protective effects of EELM was evaluated by measuring serum enzyme levels and antioxidants status in the liver and brain, further histopathological analysis was performed respectively.
Results: The acute toxicity study did not report any mortality or toxicity signs in animals. PCM toxicity led to a statistically increase in the liver and body weight, along with brain water content. The PCM-intoxicated group exhibited a marked reduction in the level of superoxide dismutase (SOD) and glutathione (GSH) in the brain and liver, as well as an increase in lipid peroxidation and serum biomarkers (AST, ALT, ALP, and total bilirubin). EELM significantly ( ) reduced liver injury by inhibiting ALT, AST and ALP levels in serum. SOD, GSH and MDA liver content were significantly ( ) elevated by EELM, compared to PCM treated rats. Comparing the treatment and induced group, the treated group successfully recovered the activity of antioxidant levels and also been acknowledged for restored liver functioning by alleviating oxidative stress and also GSH level in brain was significantly increased by EELM and preserved the histology of brain, which was chronically produced over a period of 30 days.
Conclusion: The findings of this investigation indicate the traditional use of Lemna minor in hepatoprotection and neuroprotection by regulating oxidative stress and mitigating reactive oxygen species (ROS). The insights gained from this research contribute to the development of novel therapeutic agents and paves the way for further studies on Lemna minor to enhance health outcomes, particularly in the management of neurodegenerative diseases
Ischemic stroke subtypes and migraine with visual aura in the ARIC study
OBJECTIVE: To investigate the association among migraine, ischemic stroke, and stroke subtypes in the Atherosclerosis Risk in Communities (ARIC) study.
METHODS: In this ongoing, prospective, longitudinal community-based cohort study, participants were given an interview ascertaining migraine history in 1993-1995, and were followed for all vascular events, including stroke. All stroke events over the subsequent 20 years were adjudicated and classified into stroke subtypes by standard definitions. Cox proportional hazards models adjusted for stroke risk factors were used to study the relationship between migraine and ischemic stroke, overall, as well as stroke subtypes (cardioembolic, lacunar, or thrombotic).
RESULTS: We identified 1,622 migraineurs among 12,758 participants. Mean age of the study population at the 3rd clinical visit was 59 years. When compared to nonheadache participants, there was a significant association between migraine with visual aura and ischemic stroke (hazard ratio [HR] 1.7, 95% confidence interval [CI] 1.2-2.6, p = 0.008). Migraine without visual aura was not significantly associated with ischemic stroke (HR 1.2, CI 1.0-1.8, p = 0.28) when compared to nonheadache participants. Among the 3 subtypes of ischemic stroke evaluated, migraine with visual aura was significantly associated only with cardioembolic stroke (HR 3.7, 95% CI 1.6-8.7, p = 0.003).
CONCLUSION: In participants with migraine with visual aura in late middle age, increased risk of cardioembolic stroke was observed. Migraine with visual aura was linked to increased stroke risk, while migraine without visual aura was not, over the period of 20 years. These results are specific to older migraineurs
Dynamics of nanoscale droplets on moving surfaces
We use molecular dynamics (MD) simulations to investigate the dynamic wetting of nanoscale water droplets on moving surfaces. The density and hydrogen bonding profiles along the direction normal to the surface are reported, and the width of the water depletion layer is evaluated first for droplets on three different static surfaces: silicon, graphite, and a fictitious superhydrophobic surface. The advancing and receding contact angles, and contact angle hysteresis, are then measured as a function of capillary number on smooth moving silicon and graphite surfaces. Our results for the silicon surface show that molecular displacements at the contact line are influenced greatly by interactions with the solid surface and partly by viscous dissipation effects induced through the movement of the surface. For the graphite surface, however, both the advancing and receding contact angles values are close to the static contact angle value and are independent of the capillary number; i.e., viscous dissipation effects are negligible. This finding is in contrast with the wetting dynamics of macroscale water droplets, which show significant dependence on the capillary number
Investigation of the Synergistic Anti-pyretic and Anti-inflammatory Activity of Sonchus wightianus DC, Paracetamol and Indomethacin Combination in Rat Models
Introduction: In conventional Indian medicine, several plants have long been utilized to treat various ailments. Among these herbal species, Sonchus wightianus DC is known for anti-inflammatory and antipyretic effects attributed to compound found in its leaves such as fatty acid methyl esters, sterol and triterpenoids. Induced pyrexia and inflammation in animal models serves to investigate the potential synergistic interactions between traditional herbal remedies and standard medication.
Aims and Objectves: Thus, this research aimed to evaluate the anti-pyretic and anti-inflammatory properties of methanolic extract obtained from Sonchus wightianus DC leaves tested alone and in combination with classic anti-inflammatory agents using the Carrageenan paw edema and anti-pyretic agent using yeast-induced pyrexia in Wistar rats.
Methods: Soxhlet extraction was used to obtain the methanolic extract. Inflammation was induced by a 1% (w/v) carrageenan injection, while 20% Brewer\u27s yeast triggered pyrexia in male Wistar rat. The antipyretic activity was evaluated by taking the body temperature at various hours, while the anti-inflammatory activity was assessed by measuring the paw and cytokines (TNF-α, IL-6, IL-1β).
Results: The research investigation discovered that the extract of Sonchus wightianus DC along with varying doses of Indomethacin and Paracetamol, considerably reduced raised body temperature and avoided inflammation, exhibiting percentage inhibition. The study further revealed that at a dosage of 300 mg/kg of the plant extract, 300 mg/kg plant extract combined with Paracetamol (150 mg/kg), and 300 mg/kg plant extract combined with Indomethacin (10 mg/kg), there was a marked reduction in paw edema and pyrexia in the experimental models. Moreover, the extract was found to substantially lower serum levels of key inflammatory mediators, including IL-1β, IL-6, and TNF-α.
Conclusion: These findings indicates that Sonchus wightianus DC extract has potential therapeutic benefits in managing inflammation and fever, especially when combined with standard drugs like Paracetamol and Indomethacin
Adapting the HHL algorithm to (non-unitary) quantum many-body theory
Rapid progress in developing near- and long-term quantum algorithms for
quantum chemistry has provided us with an impetus to move beyond traditional
approaches and explore new ways to apply quantum computing to electronic
structure calculations. In this work, we identify the connection between
quantum many-body theory and a quantum linear solver, and implement the
Harrow-Hassidim-Lloyd (HHL) algorithm to make precise predictions of
correlation energies for light molecular systems via the (non-unitary)
linearised coupled cluster theory. We alter the HHL algorithm to integrate two
novel aspects- (a) we prescribe a novel scaling approach that allows one to
scale any arbitrary symmetric positive definite matrix A, to solve for Ax = b
and achieve x with reasonable precision, all the while without having to
compute the eigenvalues of A, and (b) we devise techniques that reduce the
depth of the overall circuit. In this context, we introduce the following
variants of HHL for different eras of quantum computing- AdaptHHLite in its
appropriate forms for noisy intermediate scale quantum (NISQ), late-NISQ, and
the early fault-tolerant eras, as well as AdaptHHL for the fault-tolerant
quantum computing era. We demonstrate the ability of the NISQ variant of
AdaptHHLite to capture correlation energy precisely, while simultaneously being
resource-lean, using simulation as well as the 11-qubit IonQ quantum hardware
Unveiling Potent Anti-Asthmatic Effect of Curcumin in Combination with Salmeterol in Swiss Albino Mice
Background: Asthma is a long-term inflammatory respiratory condition marked by alterations in the airways and an increase in inflammatory cell infiltration. It has been observed that Curcumin possesses immune-modulating, anti-inflammatory, and relaxing properties for smooth muscle in the airways. Salmeterol is believed to ease the smooth muscles of the airways.
Objective: Swiss Albino mice were used in the research to examine the combination anti-asthmatic effects of Curcumin and Salmeterol in asthma produced by ova albumin and milk induced eosinophilia and leucocytosis.
Methods: The mice received pre-treatment with Curcumin (10 mg/kg, 20 mg/kg intraperitoneally) as well as Salmeterol (5 mg/kg) after being stimulated with an Ovalbumin (OVA) challenge and milk. After the induction period, various hematological, biochemical, molecular (ELISA), and histological analyses were performed.
Results: The findings demonstrated that the combined treatment decreased the animal’s overall leukocyte and eosinophil numbers in a manner that was dose-dependent. Additionally, the therapy reduced albumin and overall protein amount in serum, BALF and lung tissues, facilitated changes in haematological parameters, and reduced the rise of Th2 cytokines (IL-4, TNF-α, IL-13) levels that is induced by OVA in lungs and BALF, total IgE level in serum. The combined action of Curcumin and Salmeterol reduced OVA-induced inflammatory influx and ultrastructural abnormalities, according to histopathological evaluation.
Conclusion: The findings of this investigation demonstrate that curcumin and salmeterol together possess anti-asthmatic effects through suppressing Th2 triggered immune response and possessing an anti-inflammatory effect and anti-allergic effect. Thus combination of treatments might be a novel technique for managing asthma
Elevated TCA cycle function in the pathology of diet-induced hepatic insulin resistance and fatty liver
The manner in which insulin resistance impinges on hepatic mitochondrial function is complex. Although liver insulin resistance is associated with respiratory dysfunction, the effect on fat oxidation remains controversial, and biosynthetic pathways that traverse mitochondria are actually increased. The tricarboxylic acid (TCA) cycle is the site of terminal fat oxidation, chief source of electrons for respiration, and a metabolic progenitor of gluconeogenesis. Therefore, we tested whether insulin resistance promotes hepatic TCA cycle flux in mice progressing to insulin resistance and fatty liver on a high-fat diet (HFD) for 32 weeks using standard biomolecular and in vivo (2)H/(13)C tracer methods. Relative mitochondrial content increased, but respiratory efficiency declined by 32 weeks of HFD. Fasting ketogenesis became unresponsive to feeding or insulin clamp, indicating blunted but constitutively active mitochondrial β-oxidation. Impaired insulin signaling was marked by elevated in vivo gluconeogenesis and anaplerotic and oxidative TCA cycle flux. The induction of TCA cycle function corresponded to the development of mitochondrial respiratory dysfunction, hepatic oxidative stress, and inflammation. Thus, the hepatic TCA cycle appears to enable mitochondrial dysfunction during insulin resistance by increasing electron deposition into an inefficient respiratory chain prone to reactive oxygen species production and by providing mitochondria-derived substrate for elevated gluconeogenesis
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