Formulation of Polymer-Augmented Surfactant-Based Oil-Water Microemulsions for Application in Enhanced Oil Recovery.

This research explores the development of engineered oil-water microemulsions stabilized by a synergistic combination of polymer and surfactant to enhance stability and interfacial properties for improved enhanced oil recovery (EOR). Conventional surfactant-stabilized emulsions often suffer from phase instability and limited wettability alteration during water flooding and chemical injection, hindering the EOR efficiency. In contrast, our formulations incorporating polymers significantly increase the emulsion viscosity and resilience to temperature fluctuations, resulting in enhanced phase stability.

Computational investigation of novel synthetic analogs of C-1'β substituted remdesivir against RNA-dependent RNA-polymerase of SARS-CoV-2.

Remdesivir, a C-nucleotide prodrug binds to the viral RNA-dependent-RNA polymerase () and inhibits the viral replication by terminating RNA transcription prematurely. It is reported in literature that interaction between the C-1'β-CN moiety of Remdesivir () and the Ser861 residue in enzyme, causes a delayed chain termination during the RNA replication process and is one of the important aspect of its mechanism of action. In the pursuance of increasing the biological activity of and enhancing the SAR studies, against RNA viruses, we have designed its fourteen C1'β substituted analogs, - bearing 4/5-membered heterocyclic rings.

Self-care practices and quality of life of filariasis patients in a gram panchayat of Paschim Burdwan district, West Bengal, India.

Background & Objectives: Self-care management is one of the important components in the goal of elimination of lymphatic filariasis (LF) and Quality of Life (QoL) has become an important deliverable in the present day health care system. The objective was to assess the self-care management of the affected limb and to find out the quality of life who were suffering from lymphoedema.

Methods: This was a community-based cross-sectional epidemiological study conducted during 2019-2020 in a Gourbazar gram panchayat area of Paschim Burdwan district of West Bengal, India.

Multistep Synthesis of Analogues of Remdesivir: Incorporating Heterocycles at the C-1' Position.

Studies suggest that the 1'β-CN moiety in remdesivir sterically clashes with the Ser861 residue of the RNA-dependent-RNA polymerase (RdRp), causing a delayed chain termination in the RNA replication process. Replacing C1'β-CN with 5-membered heterocycles such as tetrazoles, oxadiazoles, and triazoles can augment the inhibitory activity and pharmacokinetic profile of C-nucleotides. Synthesis of tetrazole-, triazole-, and oxadiazole-integrated C1' analogues of remdesivir was attempted using general synthetic routes.

Experimental Investigation of the Synergistic Effect of Two Nonionic Surfactants on Interfacial Properties and Their Application in Enhanced Oil Recovery.

In chemically enhanced oil recovery (EOR), surfactants are conventionally used to lower the interfacial tension (IFT) at the water-oil interface, alter the rock wettability, and help in the emulsification of trapped oil after primary and secondary modes of recovery. A mixture of surfactants is usually more effective than a single surfactant with enhanced surface or interfacial properties. The primary objective of this study is to examine the synergistic effects of two nonionic surfactants (Tergitol 15-S-12 and PEG 600) on surface properties, such as surface tension, IFT, and wettability alteration, in the context of EOR.

Application of α-MnO nanoparticles for residual oil mobilization through surfactant polymer flooding.

Injection of surfactant and polymer slug is among the most effective chemical enhanced oil recovery processes. The only problem encountered with the surfactant polymer (SP) flooding is the loss of surface-active agents that reduce the efficiency of surfactants in the chemical slug. Various attempts to modify SP flooding have been made previously so that the surfactant loss due to adsorption could be reduced.

Application of Novel Colloidal Silica Nanoparticles in the Reduction of Adsorption of Surfactant and Improvement of Oil Recovery Using Surfactant Polymer Flooding.

Surfactant polymer flooding is one of the most common chemical enhanced oil recovery techniques, which improves not only the microscopic displacement of the fluid through the formation of the emulsion but also the volumetric sweep efficiency of the fluid by altering the viscosity of the displacing fluid. However, one constraint of surfactant flooding is the loss of the surfactant by adsorption onto the reservoir rock surface. Hence, in this study, an attempt has been made to reduce the adsorption of the surfactant on the rock surface using novel colloidal silica nanoparticles (CSNs).

A mechanistic investigation of low salinity water flooding coupled with ion tuning for enhanced oil recovery.

Oil recovery by low salinity water flooding (LSWF) from carbonate reservoirs has gained tremendous attention in recent years due to its cost-effectiveness and environment-friendly nature. The mechanisms of low salinity water flooding for enhanced oil recovery are very complex and depend on the mineralogy of the formation rock, properties of injection brine and reservoir fluids. The present work aimed at the optimization of salinity and concentration of potential determining ions (PDIs) in injection water for enhanced oil recovery from carbonate reservoirs.

Drain in laparoscopic cholecystectomy in acute calculous cholecystitis: a randomised controlled study.

Background: There is paucity of evidence regarding the role of drain in laparoscopic cholecystectomy (LC) in acute calculous cholecystitis (ACC), and surgeons have placed the drains based on their experiences, not on evidence-based guidelines. This study aims to assess the value of drain in LC for ACC in a randomised controlled prospective study.

Patients And Methods: All patients with mild and moderate ACC undergoing LC were assessed.

Characterization of Hydrophobically Modified Polyacrylamide in Mixed Polymer-Gemini Surfactant Systems for Enhanced Oil Recovery Application.

The study deals with the synthesis and characterization of the hydrophobically modified polyacrylamide (HMPA) copolymer and its functional property evaluation in mixed polymer-gemini surfactant systems for application in enhanced oil recovery (EOR). The copolymer was initially prepared in the laboratory using acrylamide and -phenylacrylamide monomer units via an addition polymerization route. The synthesized copolymer was characterized by Fourier transform infrared and proton nuclear magnetic resonance to identify suitable functional groups in the compound.

Stabilization of Dispersed Oil Droplets in Nanoemulsions by Synergistic Effects of the Gemini Surfactant, PHPA Polymer, and Silica Nanoparticle.

Nanoemulsion systems comprising n-heptane (oleic component), stabilized by the {gemini surfactant (14-6-14 GS) + polymer [partially hydrolyzed poly-acrylamide (PHPA)] + silica (SiO) nanoparticle} shell and dispersed in aqueous phase, were synthesized by ultrasonication (high-energy method). Influence of ultrasonication time on nanoemulsion kinetics was investigated to predict the saturation droplet diameter. Morphological analysis by transmission electron cryomicroscopy imaging showed that oleic phase appears as uniformly dispersed spherical droplets in 14-6-14 GS-stabilized nanoemulsion, which on PHPA addition changes into a network structure consisting of larger oil droplets.

Synthesis, characterization, physical and thermodynamic properties of a novel anionic surfactant derived from .

The present study deals with the synthesis, characterization, physical and thermodynamic properties of a novel anionic surfactant derived from for its potential application against conventional non-biodegradable surfactants. The synthesized surfactant was characterized by FTIR, GC-MS, EDX and FESEM analyses. The surfactant showed good thermal stability at different temperatures as obtained from TGA studies.

A case of choledochoduodenal fistula - an unusual case report.

Choledochoduodenal fistula (CDF) is an abnormal communication between the choledochus and the duodenum, accounts for 5-25% of all internal biliary fistulas. Here, we report a case of CDF secondary to chronic duodenal ulcer who presented with cholangitis. CDF is suspected in case of pneumobilia, and surgery is recommended for refractory cases.

Malignant Tumor at D-4 Mimicking Wilkie's Syndrome.

Primary carcinoma of the duodenum is rare. Here we present a case of megaduodenum due to duodenal adenocarcinoma mimicking Wilkie's syndrome which was managed by resection and anastomosis.

Ileosigmoid knot.

Ileosigmoid knotting, also known as compound volvulus or double Volvulus, is a rare cause of acute intestinal obstruction. In this condition the ileum wraps around the base of the sigmoid colon and forms a knot. The condition is serious, generally progressing rapidly to gangrene of both ileum and sigmoid colon.

Protective therapy with novel chromone derivative against Leishmania donovani infection induces Th1 response in vivo.

Background: Visceral leishmaniasis is a chronic protozoan disease caused by Leishmania donovani, an obligatory intracellular parasite that resides and multiplies within macrophages of the reticuloendothelial system. The aim of this study was to evaluate the efficacy of nine novel synthetic chromone derivatives as antileishmanial molecules in experimental murine visceral leishmaniasis.

Methods: In vitro activity of the molecules (2, 5 and 10 μg/ml) was assessed against promastigotes of both pentavalent antimonial-responsive strain AG83 and pentavalent antimonial-resistant strain GE1F8R at days 2 (48 h), 4 (96 h) and 6 (144 h).

Bronchobiliary fistula.

Bronchobiliary fistula is a very rare complication of liver abscess. It presents with biliptysis (bile in cough), and chronic cough. Here we present a case of intractable biliptysis from a bronchobiliary fistula secondary to a liver abscess with biliary obstruction.

Isotope effects on the enzymatic and nonenzymatic reactions of chorismate.

The important biosynthetic intermediate chorismate reacts thermally by two competitive pathways, one leading to 4-hydroxybenzoate via elimination of the enolpyruvyl side chain, and the other to prephenate by a facile Claisen rearrangement. Measurements with isotopically labeled chorismate derivatives indicate that both are concerted sigmatropic processes, controlled by the orientation of the enolpyruvyl group. In the elimination reaction of [4-2H]chorismate, roughly 60% of the label was found in pyruvate after 3 h at 60 degrees C.

Stereocontrol in organic synthesis using silicon-containing compounds. Studies directed towards the synthesis of ebelactone A.

Several approaches to the synthesis of ebelactone A 2 are described, culminating in the synthesis of the benzenesulfonate of 2-epi-ebelactone A 161. All the approaches were based on three fragments A, B and C, originally defined in general terms in, but eventually used as the aldehyde 72, the allenylsilane 3 and the aldehyde 139, respectively. They were joined, first B with C, and then B+C with A.

Charge optimization increases the potency and selectivity of a chorismate mutase inhibitor.

The highest affinity inhibitor for chorismate mutases, a conformationally constrained oxabicyclic dicarboxylate transition state analogue, was modified as suggested by computational charge optimization methods. As predicted, replacement of the C10 carboxylate in this molecule with a nitro group yields an even more potent inhibitor of a chorismate mutase from Bacillus subtilis (BsCM), but the magnitude of the improvement (roughly 3-fold, corresponding to a DeltaDeltaG of -0.7 kcal/mol) is substantially lower than the gain of 2-3 kcal/mol binding free energy anticipated for the reduced desolvation penalty upon binding.