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Rapid nucleation of tetrahydrofuran (THF) hydrate is essential for developing a THF hydrate-based cold storage technology. Earlier works have hypothesized the role of aluminum complexes in initiating the nucleation of clathrate hydrates using aluminum metal electrodes and substrates. This study investigates if the nucleation promotional effect of hydrate can be achieved using the aluminum salt, AlCl3, due to the formation of aluminum aqua complexes in water. Metal chlorides NaCl and MgCl2 are also utilized to evaluate the effect of cation type in initiating nucleation, i.e., the effect of charge/radius ratio. The induction time is measured in a stirred reactor at various subcoolings and concentrations of 0.05, 0.1, 0.5, 1, and 2 wt %. The nucleation time is studied in two reactor configurations based on the nature of salt introduction in the THF solution, i.e., salt premixed in solution and salt injected inside the solution. The sudden rise in the reactor temperature due to hydrate formation is used as an indicator of hydrate formation. Results indicate that AlCl3 promotes hydrate nucleation as AlCl3 reduces induction time by 92.2% at 0.05 wt % concentration compared with water. Nearly instantaneous nucleation is also achieved by directly injecting AlCl3. MgCl2 and NaCl do not show a similar effect on induction time as AlCl3. The pH and Raman spectra measurements with and without salts are carried out to explain the effect of cations on the THF-water solution.
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The sensitive nature of molecular hydrogen (H2) interaction with the surfaces of pristine and functionalized nanostructures, especially two-dimensional materials, has been a subject of debate for a while now. An accurate approximation of the H2 adsorption mechanism has vital significance for fields such as H2 storage applications. Owing to the importance of this issue, we have performed a comprehensive density functional theory (DFT) study by means of several different approximations to investigate the structural, electronic, charge transfer and energy storage properties of pristine and functionalized graphdiyne (GDY) nanosheets. The dopants considered here include the light metals Li, Na, K, Ca, Sc and Ti, which have a uniform distribution over GDY even at high doping concentration due to their strong binding and charge transfer mechanism. Upon 11% of metal functionalization, GDY changes into a metallic state from being a small band-gap semiconductor. Such situations turn the dopants to a partial positive state, which is favorable for adsorption of H2 molecules. The adsorption mechanism of H2 on GDY has been studied and compared by different methods like generalized gradient approximation, van der Waals density functional and DFT-D3 functionals. It has been established that each functionalized system anchors multiple H2 molecules with adsorption energies that fall into a suitable range regardless of the functional used for approximations. A significantly high H2 storage capacity would guarantee that light metal-doped GDY nanosheets could serve as efficient and reversible H2 storage materials.
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The spatial and the angular variants of the Imbert-Federov (IF) beam shifts and the angular Goos-Hänchen (GH) shift contribute in a complex interrelated way to the resultant beam shift in partial reflection at planar dielectric interfaces. Here, we show that the two variants of the IF effects can be decoupled and separately observed by weak value amplification and subsequent conversion of spatial âangular nature of the beam shifts using appropriate pre and post selection of polarization states. Such optimized weak measurement schemes also enable one to nullify one effect (either the GH or the IF) and exclusively observe the other. We experimentally demonstrate this and illustrate various other intriguing manifestations of optimized weak measurements in elliptical and / or linear polarization basis. We also present a Poincare sphere based analysis on conversion / retention of the angular or spatial nature of the shifts with pre and post selection of states in weak measurement. The demonstrated ability to amplify, controllably decouple or combine the beam shifts via weak measurements may prove to be valuable for understanding the different physical contributions of the effects and for their applications in sensing and precision metrology.
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This work aims to efficiently capture CO2 on two-dimensional (2D) nanostructures for effective cleaning of our atmosphere and purification of exhausts coming from fuel engines. Here, we have performed extensive first principles calculations based on density functional theory (DFT) to investigate the interaction of CO2 on a recently synthesized ZnO monolayer (ZnO-ML) in its pure, defected and functionalized form. A series of rigorous calculations yielded the most preferential binding configurations of the CO2 gas molecule on a ZnO-ML. It is observed that the substitution of one oxygen atom with boron, carbon and nitrogen on the ZnO monolayer resulted into enhanced CO2 adsorption. Our calculations show an enriched adsorption of CO2 on the ZnO-ML when substituting with foreign atoms like B, C and N. The improved adsorption energy of CO2 on ZnO suggests the ZnO-ML could be a promising candidate for future CO2 capture.
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Owing to its high energy density, the potential of hydrogen (H2) as an energy carrier has been immense, however its storage remains a big obstacle and calls for an efficient storage medium. By means of density functional theory (DFT) in spin polarized generalized gradient approximation (GGA), we have investigated the structural, electronic and hydrogen storage properties of a light alkali metal (Li, Na) functionalized fluorographene monolayer (FG). Metal adatoms bind to the FG with significantly high binding energy, much higher than their cohesive energies, which helps to achieve a uniform distribution of metal adatoms on the monolayer and consequently ensure reversibility. Due to a difference of electronegativities, each metal adatom transfers a substantial amount of its charge to the FG monolayer and attains a partial positive state, which facilitates the adsorption of multiple H2 molecules around the adatoms by electrostatic as well as van der Waals interactions. To get a better description of H2 adsorption energies with metal-doped systems, we have also performed calculations using van der Waals corrections. For both the functionalized systems, the results indicate a reasonably high H2 storage capacity with H2 adsorption energies falling into the range for the practical applications.
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The optical analogue of quantum weak measurements has shown considerable promise for the amplification and observation of tiny optical beam shifts, namely Goos-Hänchen (GH) and Imbert-Fedorov (IF) shifts. Here, we demonstrate simultaneous weak value amplification of both the angular GH and the IF shifts in partial reflection of a fundamental Gaussian beam at planar dielectric interfaces. We employ pre and postselection schemes with appropriate linear polarization basis states for simultaneous weak measurements and amplification of both of these shifts. The experimentally observed enhancement of the beam shifts and their dependence on the angle of incidence are analyzed/interpreted via theoretical treatment of weak measurements.
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Novel findings in microbiology question the long-standing paradigm that a healthy pregnancy implies a sterile uterus. It now seems that the placenta is frequently colonized with bacteria, and a placental microbiome has been identified. Recent literature findings are summarized here, and an attempt is made to separate pathological bacterial presence from a naturally occurring microbiome.
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Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Feto/microbiologia , Microbiota , Placenta/microbiologia , Líquido Amniótico/microbiologia , Feminino , Desenvolvimento Fetal , Humanos , Lactente , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Nascimento Prematuro/etiologiaRESUMO
The required load in a typical microgrid structure fluctuates from hour to hour. Based on the peaks and troughs of the load demand curve, the power system utilities preset different price of electricity at various periods of the same day which is referred to as time-of-use (TOU) pricing policy. An optimal economic strategy called demand side management (DSM) reduces load during peak hours by shifting the elastic loads and compensates the shifted load by increasing the demand during valley hours. This recreates the total demand pattern on the demand price elasticity relation. The novel benefaction of this research suggests a DSM approach based on a hybrid intelligence technique to attain a compromised solution between minimum generation costs and pollutants emitted by DERs of an LV grid-connected microgrid system. Several grid involvement strategies, power market pricing types, and demand response mechanisms are examined in five separate instances for the microgrid system. The outcomes achieved in each example show that the recommended DSM technique may be applied and is appropriate in terms of cost reduction. When 30-40% of customers participated in the DSM curriculum, the generation cost was reduced by 10-13%. Environment constrained economic dispatch provided a superior compromise amongst lowest generation cost and emission for different microgrid load models. Statistical analysis and comparison of the results from previously published literatures validates the superiority of the proposed approach incorporated with DSM policy.
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BACKGROUND: Diabetic nephropathy (DN), a severe complication of diabetes, involves a range of renal abnormalities driven by metabolic derangements. Metabolomics, revealing dynamic metabolic shifts in diseases like DN and offering insights into personalized treatment strategies, emerges as a promising tool for improved diagnostics and therapies. METHODS: We conducted an extensive literature review to examine how metabolomics contributes to the study of DN and the challenges associated with its implementation in clinical practice. We identified and assessed relevant studies that utilized metabolomics methods, including nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) to assess their efficacy in diagnosing DN. RESULTS: Metabolomics unveils key pathways in DN progression, highlighting glucose metabolism, dyslipidemia, and mitochondrial dysfunction. Biomarkers like glycated albumin and free fatty acids offer insights into DN nuances, guiding potential treatments. Metabolomics detects small-molecule metabolites, revealing disease-specific patterns for personalized care. CONCLUSION: Metabolomics offers valuable insights into the molecular mechanisms underlying DN progression and holds promise for personalized medicine approaches. Further research in this field is warranted to elucidate additional metabolic pathways and identify novel biomarkers for early detection and targeted therapeutic interventions in DN.
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Retinopatia Diabética , Metabolômica , Metabolômica/instrumentação , Metabolômica/métodos , Humanos , Animais , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/metabolismo , Diagnóstico Precoce , Progressão da Doença , Biomarcadores , Inflamação/metabolismoRESUMO
Noise removal and lesser computational run time of the digital holographic numerical reconstruction procedure are the critical issues for effective and efficient identification of three-dimensional (3D) particle fields. The present study suggests an improved reconstruction procedure based on the superposition principle. The effectiveness of this proposed method is evaluated using both simulated and experimental data of a 3D particle field. Influence of object-particle number density and sample volume depth on the reconstructed particle field is investigated. There is a reduction in computational run time (as high as 50%) and significant increase in reconstruction effectiveness (as high as 7 times increase) due to the proposed method as compared to the literature (Opt. Express 18, 2426, 2010 and Opt. Express 12, 2270, 2004).
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The 3D distribution of a particle field by digital holography is obtained by 3D numerical reconstruction of a 2D hologram. The proper identification of particles from the background during numerical reconstruction influences the overall effectiveness of the technique. The selection of a suitable threshold value to segment particles from the background of reconstructed images during 3D holographic reconstruction process is a critical issue, which influences the accuracy of particle size and number density of reconstructed particles. The object particle field parameters, such as depth of sample volume and density of object particles, influence the optimal threshold value. The present study proposes a novel technique for the determination of the optimal threshold value of a reconstructed image. The effectiveness of the proposed technique is demonstrated using both simulated and experimental data. The proposed technique is robust to variation in optical properties of particle and background, depth of sample volume, and number density of object particle field. The particle diameter obtained from the proposed threshold technique is within 5% of that obtained from the particle size analyzer. There is a maximum ten times increase in reconstruction effectiveness by using the proposed automatic threshold technique in comparison with the fixed manual threshold technique.
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The digital holography has immense potential related to many applications of science and engineering. It has many advantages compared to conventional holography i.e. characterization of online dynamic phenomena and imaging in small scale microscopic systems. However, its primary limitation is the size of sensors and number of sensors compared to the conventional holographic plate. The critical issue of digital holography is the numerical reconstruction procedure. The present study proposes a new reconstruction algorithm known as 'Within Depth Intensity Averaging (WDIA)'. The effectiveness of the WDIA algorithm is demonstrated using both experiment and simulation for single particle, 2D and 3D distribution of particles. The 3D distribution of particles is experimentally simulated by using gelatin film on the glass slide. The particle images from digital holography compare well with that of microscopic images demonstrating the success of the proposed algorithm compared to the existing reconstruction procedure. The depth error significantly reduces (maximum 100%) and particles of any size can be characterized by the WDIA reconstruction algorithm contrary to the existing reconstruction algorithm available in literature. The effect of particle number density, particle size and sample volume depth on reconstruction effectiveness using the WDIA algorithm has been investigated and compared with the literature demonstrating its superiority in performance.
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Loop-mediated isothermal amplification or LAMP has been identified to be an efficient technology for point-of-care diagnostics. Paper-based LAMP technique has tremendous potential in replacing the existing tube-based technology as the manufacturing cost of a paper-based device is comparatively lower and easy-to-use. LAMP-based paper diagnostic device for Mycobacterium tuberculosis (MTB) detection is of extreme importance as it will help in early and rapid diagnosis of the affected patients. The fabrication of these devices requires assessment of design parameters on the extent of LAMP amplification reaction. Hence, CFD studies would be extremely beneficial from the design perspective. The current work presents an insight into the CFD simulations for LAMP amplification reaction on a porous paper membrane (nitrocellulose membrane). The convection-diffusion-reaction model is solved on a COMSOL Multiphysics 5.0 platform. Studies on effect of pore size, aspect ratio and initial DNA concentration on the extent of DNA amplification reaction have been carried out. The current paper-based technique is effective in detecting a minimum of 5 copies of DNA contrasting the previous semi-quantitative technique which demonstrated the detection of minimum 98 copies. Overall, the simulation results displayed almost 96% enhancement in the DNA amplification rate on paper membrane. Graphical abstract Graphical abstract for the computational study of DNA amplification reaction via LAMP technique on a porous paper membrane.
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Simulação por Computador , DNA Bacteriano/genética , Testes Diagnósticos de Rotina , Hidrodinâmica , Mycobacterium tuberculosis/genética , Técnicas de Amplificação de Ácido Nucleico , Papel , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Análise Numérica Assistida por Computador , Porosidade , Reprodutibilidade dos TestesRESUMO
Lymphangioma of the tongue is a rare lymphatic malformation, and various authors have reported the successful use of sirolimus for its treatment. However, the safety of sirolimus in children needs further evaluation so that those who do not respond are not necessarily exposed to its potential adverse effects. We hypothesised that assessment of lymphangiogenesis can be used to predict whether the patient will respond to sirolimus, so we organised a prospective study after ethics committee approval had been given. After clinical and histological diagnoses of lymphangioma of the tongue had been confirmed, 16 patients were given sirolimus 0.8mg/day in three divided doses. Clinical response was assessed and compared with lymphatic microvessel density (LMVD), which was calculated immunohistochemically using the monoclonal antibody D2-40 as the lymphatic endothelial marker. Nine patients responded well, five partially, and two failed to respond. Mean (SD) LVD among the good responders was 21.00 (3.74), whereas among non-responders it was 8.00 (4.24). There was a significant difference in mean LVD between good responders, partial responders, and non-responders (p=0.04). Sirolimus is effective in treating children with lymphangioma of the tongue, and lymphangiogenesis is a useful therapeutic predictive marker.
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Linfangioma , Humanos , Linfangiogênese , Vasos Linfáticos , Projetos Piloto , Prognóstico , Estudos ProspectivosRESUMO
This is a prospective, controlled, randomized clinical study to evidence the role of nitrosative stress in development of overt neurological sign of canine distemper (CD). The enrollment of cases wasa made on basis of overt sign of CD (n=139) and the findings were compared with apparently healthy dogs (n=15). The CD specific immunoglobulins resulted in 94 confirmed positive cases. The nitric oxide (NO) and neuronal nitric oxide synthase (nNOS) concentration in cerebrospinal fluid (CSF) (18.08 ± 2.76, 415.84 ± 46.24, respectively) and plasma (32.68 ± 4.31, 321.31 ± 102.30, respectively) were significantly (P<0.05) elevated as compared to healthy control group. The concentration of neuron specific enolase (NSE) in CSF and plasma were also significantly (P<0.05) higher in dogs suffering from CD. The significant differences in other biochemical parameters like total protein, albumin and globulin were found in the CSF of dogs compared with healthy control. The author concludes that NO plays a role in pathophysiology of neurological form of CD and nNOS and NSE estimation in CSF and plasma could help in making early diagnosis of clinical cases.
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Field experiments were conducted to study the effect of irrigation and nitrogen levels on radiation use efficiency (RUE), radiation extinction coefficient (κ) and temporal variation of leaf area index (LAI) and fraction intercepted photosynthetically active radiation (fIPAR). The LAI of wheat increased with increase in irrigation and nitrogen levels. The fIPAR also followed trend similar to LAI. The LAI and fIPAR showed logarithmic relationship with R2 value of 0.92 and 0.93 for the years 2013-2014 and 2014-2015, respectively. The κ value varied between 0.41 and 0.78 and was significantly affected by nitrogen levels but was not influenced by irrigation levels. The grain and above ground biomass (AGB) yields of wheat were not affected significantly by irrigation levels. However, application of 160 kg N ha-1 (N160) registered higher grain (12-33%) and AGB (22-25%) yeilds as compared to that with application of 40 kg N ha-1 (N40). Similar to AGB, the total intercepted photosynthetically active radiation (TIPAR) was not affected by irrigation levels but N160 treatment registered 9-20% higher TIPAR compared to N40 treatment. The linear relationship between TIPAR and AGB revealed that 83-86% variation in AGB yield of wheat can be explained by TIfIPAR. The RUE of wheat under three irrigations (I3) was 6 and 18% higher (P < 0.05) than the five (I5) and two (I2) irrigation treatments, respectively for the year 2013-2014. However, there was no significant effect of irrigation on RUE of wheat in the year 2014-2015. N160 treatment registered 5-13% higher RUE than the N40 treatment. Thus wheat may be grown with three irrigations (CRI, flowering and grain filling) and 160 kg N ha-1 for higher RUE without significant reduction in AGB of wheat compared to five irrigation levels in semi-arid location of Delhi region.
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OBJECTIVE: To examine the timing and microbiology of neonatal sepsis in a population-based surveillance in the Indian community setting. STUDY DESIGN: All live born infants in 223 villages of Odisha state were followed at home for 60 days. Suspect sepsis cases were referred to study hospitals for further evaluation including blood culture. RESULTS: Of 12 622 births, 842 were admitted with suspected sepsis of whom 95% were 4 to 60 days old. Culture-confirmed incidence of sepsis was 6.7/1000 births with 51% Gram negatives (Klebsiella predominating) and 26% Gram positives (mostly Staphylococcus aureus). A very high level of resistance to penicillin and ampicillin, moderate resistance to cephalosporins and extremely low resistance to Gentamicin and Amikacin was observed. CONCLUSION: The bacterial burden of sepsis in the Indian community is not high. Judicious choice of empiric antibiotics, antibiotic stewardship and alternate modalities should be considered for the management or prevention of neonatal sepsis in India.
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Antibacterianos , Klebsiella , Sepse Neonatal , Staphylococcus aureus , Antibacterianos/classificação , Antibacterianos/uso terapêutico , Gerenciamento Clínico , Resistência Microbiana a Medicamentos , Feminino , Humanos , Incidência , Índia/epidemiologia , Recém-Nascido , Klebsiella/efeitos dos fármacos , Klebsiella/isolamento & purificação , Masculino , Sepse Neonatal/epidemiologia , Sepse Neonatal/microbiologia , Sepse Neonatal/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificaçãoRESUMO
Ivermectin is one of the most effective and widely used antiparasitic agents ever discovered because of its broad spectrum activity against nematodes and arthropods. Therefore, the study was conducted to determine the comparative anthelmintic efficacy of ivermectin by giving through oral and subcutaneous routes in clinically infected dogs and also to check the prevalence of gastrointestinal nematode in dogs in Bhubaneswar, Odisha. Total 154 dogs with clinical signs of gastroenteritis were examined for the presence of nematodal ova in their faecal sample and 64 were found positive (41.56 %). The screened dogs were divided in to two groups (n = 10 each), first group of animals were treated with ivermectin @ 0.5 mg/kg body weight by subcutaneous route and the second group with same dose of ivermectin through oral route. Efficacy of ivermectin was evaluated based on egg per gram (EPG), haematological and biochemical parameters. It is concluded that, Prevalence of gastrointestinal nematodes are high in dogs in the climatic condition of Bhubaneswar, Odisha. Ivermectin was found effective when administered through either of the routes. Haemato-biochemical parameters were restored after administration of ivermectin and also significant reduction in EPG was found in dogs treated with ivermectin by both the routes, but no significant difference was observed in EPG between oral and subcutaneous treated dogs in various intervals of study.
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Acariotic mange in rabbits is one of the important constraints in rabbit husbandry. Sarcoptes scabies var. cuniculi and Psoroptes cuniculi are most common mites prevailed in rabbits, but Notoedres cati, is the rarest mite ever been reported in rabbit. Two New Zealand white rabbits were presented with clinical signs of pruritus, alopecia, scab and crust formation and lichenification on the upper lip, ear pinnae, eyelids, lower jaw and limbs. Deep skin scraping was taken separately from 4 to 5 different skin lesions from each rabbit, revealed mixed infestations of N. cati, S. cuniculi and P. cuniculi. Subcutaneous injection of ivermectin at weekly intervals for four weeks resulted in remission of clinical signs and improvement of health condition in rabbits. This is the first report of N. cati infestation of rabbit in Odisha.