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1.
Sci Rep ; 14(1): 9712, 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38678146

ABSTRACT

Hydromagnetically associated heat convection can greatly enhance the performance of high-efficiency thermal appliances and renewable energy sources through an optimized design. This investigation examines the production of thermodynamic irreversibility and heat convection for a double lid-driven flow within a partially porous stratified hexagonal enclosure. The top and bottom-wall are moving in the opposite direction with an equal velocity U0. The top-wall and the bottom-wall are kept at temperature Tc and Th (Th  >  Tc) while the slanted walls are assumed to be thermally insulated. A constant magnetic field is employed in the horizontal x-direction. The hexagonal cavity was filled with a micropolar hybrid nanofluid Ag-MgO/water. The system of dimensionless equations was solved by the finite difference method (FDM) associated with successive over-relaxation (SOR), successive under-relaxation (SUR), and Gauss-Seidel iteration tactics and required results are computed with problem specific program in MATLAB code. The results indicate that the Ra and the thickness of the porous layer (Xp) significantly influences heat convection and thermal irreversibility processes. The Nuavg and STotal rises 6.299% and 3.373% as ' ϕ hnf ' enhances from 0 to 4%, respectively. Furthermore, as the values of Ra, Ha, K0, and ϕ hnf increase, Beavg experiences a decline of 53.73%, 11.04%, 38.36%, and 0.09% respectively. Also, movement of wall has a significant impact on heat transfer rates and entropy production. The present study may be extended in numerous areas to mimic the problems like-(1) onset of thermo-mechanical process for solid-fluid interaction in a conduit. (2) Thermos-chemical process with extraction of ions in two-phase fluid for double layer plating on a continuously moving sheet, as region of porous stratum saturated with a class of fluid and region without porous medium occupied with other fluid.

2.
Cureus ; 15(4): e37232, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37168145

ABSTRACT

BACKGROUND: Left ventricular systolic and diastolic functions are known prognosticators for cardiovascular morbidity. One of the significant risk factors for cardiovascular diseases is obesity. The objective of this study is to determine the effect of obesity on the systolic and diastolic functions of the left ventricle on the basis of echocardiographic indices. METHODS: 75 obese and 75 averagely built subjects were studied. They had no other comorbidities. The indices of echocardiography of systolic and diastolic function were taken and assessed using recent recommendations from the European Association of Cardiovascular Imaging and the American Society of Echocardiography. RESULTS: The volume indices of systolic and diastolic function (ejection diastolic volume (EDV) and ejection systolic volume (ESV)) and iso-volumetric relaxation time (IVRT) showed a significant increase in obese subjects (p<0.05); however, the relative thickness of the wall and internal diameter were comparable to non-obese subjects. The indices of contractility like ejection fraction, early diastolic filling velocity and late diastolic filling velocity (E/A) ratio, and mitral annular velocity were significantly lower in the obese subjects as compared to non-obese subjects. It was also found that left atrial diameter in systole and diastole had a moderate association (r=0.48, P<0.0001; r=0.35, P<0.0005) while mitral inflow E/A ratio had a negative association with body mass index (BMI) (r=-0.26, P=0.0166). CONCLUSIONS: Volumetric changes and ejection are significantly altered by increased BMI. More comprehensive studies in the future are recommended to assess the same.

3.
Anal Chim Acta ; 1077: 266-272, 2019 Oct 24.
Article in English | MEDLINE | ID: mdl-31307718

ABSTRACT

Fluorescence quenching based immunoassay format for the detection of a trace amount of some nitro-explosives with a high degree of selectivity is reported in this study. The immunoassay comprises anti-explosive antibodies functionalized microtitre strips specific to the targeted explosives, pentaerythritol tetranitrate (PETN), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), and 2,4,6-trinitrotoluene (TNT). UV induced photolysis of nitro-explosive bound to targeted antibodies generates primarily nitrite ions which after the quick reaction with the detector molecule, 2,3-diaminonaphthalene (DAN), a fluorophore, quenches its fluorescence intensity, however, proportionately undergo cyclization to produce a highly fluorescent product, 2,3-naphthotriazole (NAT). The synthesized product, NAT, was verified using various chromatographic and spectrophotometric techniques. This newly developed antibody-based detection method, utilizing DAN dye, demonstrated a high selectivity towards PETN, RDX, and TNT. This method can be used as an economical testing kit for direct quantification of explosives, implying the great potential for quick, low-cost trace detection of explosives.


Subject(s)
Explosive Agents/analysis , Immunoassay/methods , Pentaerythritol Tetranitrate/analysis , Spectrometry, Fluorescence/methods , Triazines/analysis , Trinitrotoluene/analysis , 1-Naphthylamine/analogs & derivatives , Antibodies, Immobilized/immunology , Explosive Agents/immunology , Explosive Agents/radiation effects , Fluorescent Dyes/chemistry , Pentaerythritol Tetranitrate/immunology , Pentaerythritol Tetranitrate/radiation effects , Photolysis , Triazines/immunology , Triazines/radiation effects , Triazoles/chemistry , Trinitrotoluene/immunology , Trinitrotoluene/radiation effects , Ultraviolet Rays
4.
Biosens Bioelectron ; 126: 590-595, 2019 Feb 01.
Article in English | MEDLINE | ID: mdl-30500774

ABSTRACT

A new immunoassay format using thermally induced defragmentation of some nitro-explosives with a high degree of selectivity is reported. Specific antibodies against three widely used explosives, 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), and pentaerythritol tetranitrate (PETN) were generated by designing suitable haptens using geometry optimization modules. These in-house generated antibodies were used in a newly developed thermal mediated immunochemical biosensing technique which involves the binding of specific antibodies to respective nitro-explosives on a microtiter strip, resulting in the formation of specific immunocomplex. Heating the specific immuno-complex formed on microtiter wells resulted in thermal lysis of nitro-explosives to generate nitrite ions. These ions react with Griess reagent to form a colored chromophore which correlates the concentration of individual explosive in the sample. The present work fulfills the need for an improved explosive detecting system that is highly specific and capable of quickly determining the presence of nitrate containing explosives from a mixture pool.


Subject(s)
Biosensing Techniques , Explosive Agents/isolation & purification , Triazines/isolation & purification , Trinitrotoluene/isolation & purification , Antibodies/chemistry , Explosive Agents/chemistry , Haptens/chemistry , Haptens/immunology , Temperature , Triazines/chemistry , Triazines/immunology , Trinitrotoluene/chemistry , Trinitrotoluene/immunology
5.
Int J Pharm ; 485(1-2): 108-21, 2015 May 15.
Article in English | MEDLINE | ID: mdl-25735668

ABSTRACT

In the present study, nanostructured lipid carriers (NLCs) with three different lipid combinations (solid lipid:liquid lipid) were prepared through emulsification and ultrasonication using a Box-Behnken design. From the design, the best lipid combination was glyceryl monostearate and oleic acid, which gives particle of smaller size (223.73 ± 43.39nm) with high drug entrapment efficiency (78.65 ± 2.2%). In vitro release studies show that 84.60 ± 5.66% of drug was released in 24h. In vivo studies revealed that drug absorption occurs through lymphatic pathway as only 5.008 ± 0.011µg/ml of peak plasma concentration was achieved in blood plasma in presence of chylomicron inhibitor. The peak plasma concentration (Cmax) for silymarin loaded NLC was found to be 25.565 ± 0.969µg/ml as compared to silymarin suspension whose Cmax was found to be 14.050 ± 0.552 µg/ml, this confirms 2-fold increase in relative bioavailability. In vivo studies revealed that 19.268 ± 1.29µg of drug reaches to liver in 2h whereas negligible drug concentration reported in other organs. It was concluded that drug loaded NLCs was beneficial for targeting liver or other lymphatic disorders through lymphatic transport pathway. Finally, the main purpose of modifying lymphatic transport system was successfully achieved through NLCs.


Subject(s)
Drug Carriers , Glycerol/chemistry , Liver/metabolism , Lymphatic System/metabolism , Nanoparticles , Oleic Acid/chemistry , Silymarin/administration & dosage , Administration, Oral , Animals , Biological Availability , Caco-2 Cells , Chemistry, Pharmaceutical , Chylomicrons/metabolism , Emulsions , Female , Glycerol/analogs & derivatives , Humans , Hydrophobic and Hydrophilic Interactions , Intestinal Absorption , Metabolic Clearance Rate , Models, Statistical , Nanomedicine , Particle Size , Rats, Wistar , Silymarin/blood , Silymarin/chemistry , Silymarin/pharmacokinetics , Solubility , Sonication , Technology, Pharmaceutical/methods , Tissue Distribution
6.
J Drug Target ; 22(10): 871-82, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25148607

ABSTRACT

Lymphatic system is a key target in research field due to its distinctive makeup and huge contributing functions within the body. Intestinal lymphatic drug transport (chylomicron pathway) is intensely described in research field till date because it is considered to be the best for improving oral drug delivery by avoiding first pass metabolism. The lymphatic imaging techniques and potential therapeutic candidates are engaged for evaluating disease states and overcoming these conditions. The novel drug delivery systems such as self-microemulsifying drug delivery system, nanoparticles, liposomes, nano-lipid carriers, solid lipid carriers are employed for delivering drugs through lymphatic system via various routes such as subcutaneous route, intraperitoneal route, pulmonary route, gastric sub-mucosal injection, intrapleural and intradermal. Among these colloidal particles, lipid-based delivery system is considered to be the best for lymphatic delivery. From the last few decades, mesenteric lymph duct cannulation and thoracic lymph duct cannulation are followed to assess lymphatic uptake of drugs. Due to their limitations, chylomicrons inhibitors and in-vitro models are employed, i.e. lipolysis model and permeability model. Currently, research on this topic still continues and drainage system used to deliver the drugs against lymphatic disease as well as targeting other organs by modulating the chylomicron pathway.


Subject(s)
Drug Delivery Systems , Lipids/chemistry , Lymphatic System/metabolism , Administration, Oral , Animals , Biological Transport , Chylomicrons/metabolism , Humans , Liposomes , Nanoparticles
7.
Anal Chem ; 86(15): 7200-4, 2014 Aug 05.
Article in English | MEDLINE | ID: mdl-25008849

ABSTRACT

Combining synthetic macromolecules and biomolecular recognition units are promising in developing novel diagnostic and analysis techniques for detecting environmental and/or clinically important substances. Fluorescence resonance energy transfer (FRET) apta-immunosensor for explosive detection is reported using 2,4,6-trinitrotoluene (TNT) specific aptamer and antibodies tagged with respective FRET pair dyes in a sandwich immunoassay format. FITC-labeled aptamer was used as a binder molecule in the newly developed apta-immunoassay format where the recognition element was specific anti-TNT antibody labeled with rhodamine isothiocyanate. The newly developed sensing platform showed excellent sensitivity with a detection limit of the order of 0.4 nM presenting a promising candidate for routine screening of TNT in samples.


Subject(s)
Antibodies/chemistry , Aptamers, Nucleotide/chemistry , Fluorescence Resonance Energy Transfer , Trinitrotoluene/analysis , Base Sequence , Molecular Sequence Data
8.
J Hazard Mater ; 248-249: 322-8, 2013 Mar 15.
Article in English | MEDLINE | ID: mdl-23416475

ABSTRACT

Binding of electron-deficient trinitrotoluene (TNT) to the electron rich amine groups on a substrate form specific charge-transfer Jackson-Meisenheimer (JM) complex. In the present work, we report formation of specific JM complex on amine functionalized reduced graphene oxide/carbon nanotubes- (a-rGO/CNT) nanocomposite leading to sensitive detection of TNT. The CNT were dispersed using graphene oxide that provides excellent dispersion by attaching to CNT through its hydrophobic domains and solubilizes through the available OH and COOH groups on screen printed electrode (SPE). The GO was reduced electrochemically to form reduced graphene that remarkably increases electrochemical properties owing to the intercalation of high aspect CNT on graphene flakes as shown by TEM micrograph. The surface amine functionalization of dropcasted and rGO/CNT was carried out using a bi-functional cross linker ethylenediamine. The extent of amine functionalization on modified electrodes was confirmed using energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and confocal microscopy. The FTIR and Raman spectra further suggested the formation of JM complex between amine functionalized electrodes and TNT leading to a shift in peak intensity together with peak broadening. The a-rGO/CNT nanocomposite prepared electrode surface leads to ultra-trace detection of TNT upto 0.01 ppb with good reproducibility (n=3). The a-rGO/CNT sensing platform could be an alternate for sensitive detection of TNT explosive for various security and environmental applications.


Subject(s)
Ethylenediamines/chemistry , Explosive Agents/analysis , Graphite/chemistry , Nanocomposites/chemistry , Nanotubes, Carbon/chemistry , Trinitrotoluene/analysis , Electrochemical Techniques , Explosive Agents/chemistry , Trinitrotoluene/chemistry
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