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N,N‐Dimethylaniline.borane (DMAB) is a stable, multifaceted electrophilic boron agent that displays hydroboration of C = C as well as selective reduction of functional groups under reflux, microwave, and ultrasound conditions. Natural products contain a plethora of functional groups that govern the specific bioactivity. It will be interesting to correlate the change in a functional group with the concern for change in bioactivity. Current research emphasizes the influence of microwave irradiation on moderately reactive DMAB reagent towards the functional group modification of selected limonoid‐phytochemicals of Meliaceae family viz. cedrelone, azadirone, nimbin, and azadiradione. DMAB conveniently reduces the ketone, epoxide group into alcohol, and does a hydroboration reaction on the C = C bond. It does not show interest to reduce the ester group irrespective of 30 min of MW irradiation. Except for these reducing properties, the reagent DMAB unveils chemo‐selective nature in respect of different functional groups and utilizes in an asymmetric synthesis. The coalescence of amine.borane with microwave irradiation brings forth a commodious and prompt method for the selective reduction of functional groups. The bioactive efficacy of modified phytochemicals is further taken for the antimicrobial studies. [ABSTRACT FROM AUTHOR]

Objective: AURORA 2 evaluated the long‐term safety, tolerability, and efficacy of voclosporin compared to placebo in patients with lupus nephritis (LN) receiving an additional two years of treatment following completion of the one‐year AURORA 1 study. Methods: Enrolled patients continued their double‐blinded treatment of voclosporin or placebo randomly assigned in AURORA 1, in combination with mycophenolate mofetil and low‐dose glucocorticoids. The primary objective was safety assessed with adverse events (AEs) and biochemical and hematological assessments. Efficacy was measured by renal response. Results: A total of 216 patients enrolled in AURORA 2. Treatment was well tolerated with 86.1% completing the study and no unexpected safety signals. AEs occurred in 86% and 80% of patients in the voclosporin and control groups, respectively, with an AE profile similar to that seen in AURORA 1, albeit with reduced frequency. Investigator reported AEs of both glomerular filtration rate (GFR) decrease and hypertension occurred more frequently in the voclosporin than the control group (10.3% vs 5.0%, and 8.6% vs 7.0%, respectively). Mean corrected estimated GFR (eGFR) was within the normal range and stable in both treatment groups. eGFR slope over the two‐year period was −0.2 mL/min/1.73 m2 (95% confidence interval [CI] −3.0 to 2.7) in the voclosporin group and −5.4 mL/min/1.73 m2 (95% CI −8.4 to −2.3) in the control group. Improved proteinuria persisted across three years of treatment, leading to more frequent complete renal responses in patients treated with voclosporin (50.9% vs 39.0%; odds ratio 1.74; 95% CI 1.00–3.03). Conclusion: Data demonstrate the safety and efficacy of long‐term voclosporin treatment over three years of follow‐up in patients with LN. [ABSTRACT FROM AUTHOR]

Hematite nanoparticles (α‐Fe2O3) were successfully synthesised using facile and eco‐friendly hydrothermal method. Synthesised hematite nanoparticles were characterized using X‐ray diffraction, Fourier transform infrared spectroscopy, surface area analysis and transmission electron microscopy. Nano/micro particles of Hematite (1, 3&5 %, w/w) were incorporated in aerosol forming composite (AFC). For the first time, catalytic effect of nano and micro size hematite on performance of AFC has been creatively investigated with respect to combustion and fire extinguishment parameters. Incorporation of nano hematite (5 %, w/w) in AFC reduced the combustion temperature (by 11 %) and tremendously boosted the burn rate & combustion efficiency by 30&7.5 % respectively. This in turn produced the aerosols in less time and put out the fire quickly (<5 s). Hematite nano counterpart was discovered to be more promising than its micro equivalent. This exploratory study is valuable in the field of development of futuristic ultra‐fast fire extinguishants. [ABSTRACT FROM AUTHOR]

The current research focuses on the design, method development, characterization, and clinical assessment of novel irbesartan medication compounds. The objective of synthetic modification of a drug molecule is to achieve the desired properties such as enhancing the pharmacological properties and minimizing the side effects. It is a biphenyl tetrazole and an aza‐spiro compound, a highly selective, potent nonpeptide compound that belongs to the sartan group, an authorized type‐1 angiotensin II receptor (AT1), dilates the blood vessels and is used in curing of to treat high blood pressure, cardiac arrest, and renal disease in diabetics. To achieve the structural modification of the irbesartan drug, the researcher prepared the FeCl3/SiO2 catalyst and successfully used it for the acetylation, chloro acetylation reaction of irbesartan with acetyl chloride and chloroacetyl chloride. Further, the reaction is performed in presence of the catalyst and without a catalyst to elucidate the role of the catalyst. With the aid of TLC, FT‐IR, and UV–visible spectral methods, the structural interpretation of synthesized derivatives is completed. The present work illustrates a novel method of synthesis of irbesartan derivatives through safe and convenient procedures. The pharmacological evaluation of synthetic derivatives and green chemistry protocol of synthesis is under progress. [ABSTRACT FROM AUTHOR]

Nanostructured SnO2 thin films are synthesized by the chemical Spray pyrolysis method in presence of air and nitrogen as carrier gas. The study has emphasized on the impact of carrier gas on the underlying, electrical, and optical properties of the deposited thin films. XRD studies uncover that there is no variation in the crystalline structure of the film. The SnO2 thin films prepared using nitrogen as carrier gas is found more conductive as compared to the film prepared using air as a carrier gas. The change in conductivity is due to the increased oxygen deficiency in the nitrogen atmosphere. The HBM and EMA models are used to calculate particle radius by optical absorption data, showing the particle diameter is low for nitrogen as compared to air as carrier gas. The activation energy is also found to decrease in presence of nitrogen as carrier gas. This may be due to shallow donor and deep acceptor levels of semiconductors. The decrease in particle size increases the number of surface atoms, responsible for a decrease in activation energy of films. [ABSTRACT FROM AUTHOR]

Industrial waste locks are used as raw materials to reduce harmful effects on the environment and improve environmental performance. Marble clay powder can be used as a filling aid and can fill voids in concrete structures. This article will show you how to use a maximum natural sand alternative in concrete with marble powder and quarry dust. The challenge of the 21st century is to change to a new form that can support the natural system. This necessitates a radical rethinking of how to give the community infrastructure and housing. Making a concerted effort to develop novel, innovative, and alternative construction materials may be necessary. Jungles of concrete around cause's impact on the Environment and it would result in climate change. Mankind must avoid the use of things that are detrimental to the environment. So in this paper, it is decided to address the issue by adopting the use of the green concrete concept which is environmentally friendly. Green concrete is concrete made up using industrial wastes such as marble powder, quarry dust, wood ash, paper pulp, etc. Green concrete, which is capable of sustainable development, helps to reduce the consumption of natural resources, energy use, and environmental pollution. Green concrete is more cost‐effective than ordinary concrete and reduces the cost of resultant concrete by 14%–20%. It is also observed that the alkali‐aggregate reaction and sulfate attack resistance of concrete are both significantly improved. Green concrete is a useful tool for lowering environmental pollution and enhancing concrete's resistance to harsh conditions. All stages of infrastructure construction and rehabilitation will follow this trend of using new cement and techniques. Green concrete's adaptability and its performance derivatives will meet a variety of future needs. [ABSTRACT FROM AUTHOR]

The use of ordinary Portland cement (OPC) in the construction industry is inevitable. The huge production of OPC and its use in infrastructural development pose an environmental impact. Greenhouse gas emitted increases the global temperature and it is an alarming sign to everybody on the planet. Concrete is the most consuming material which is produced by using OPC and it is proven that OPC contributes a lot to CO2 emission. Hence in this study attempt is made to produce concrete by using environment‐friendly material like fly ash along with alkaline activators, which is termed Geo polymer concrete. The by‐product fly ash is widely available worldwide. It is a by‐product of thermal power plants. The use of fly ash in concrete produces less expensive and more cost‐effective concrete than concrete made up using OPC. Due to its high silicate and alumina content, fly ash reacts with an alkaline solution to create an aluminosilicate gel that binds the aggregate and results in high‐quality concrete. Fly ash is finer than cement, it occupies the pores of cement after hydration. This would result in denser concrete which gives higher strength. In comparison to ordinary concrete, fly ash‐based geopolymer concrete offers better resistance to aggressive environments and high temperatures. In the present study, an alkaline activator of molarity 8 is used to prepare geopolymer concrete. The test specimens are cast and cured for 28 days. Test results indicate that an alkaline liquid fly‐ash ratio (0.4) produces higher mechanical properties. Hence, geopolymer concrete produced in this study is found to be cost‐effective and environment friendly. [ABSTRACT FROM AUTHOR]

In oil and gas exploration, it is vital to acquire information about the bottom hole conditions. This is done in the field using wireline logging. The sonic log is one of the most prolific logs as it assists in porosity determination, cement evaluation and identification of lithology and gas‐bearing intervals. However, sonic logging tools are not always a part of the wireline logging arrangement. Still, there are sections where the logging data are missing, and in some cases, these are dependent upon old tools. The tool is incapable of recording shear wave transit times. This study explores the possibility of substituting the sonic log using machine learning and artificial intelligence techniques. These techniques can also predict the sonic log data in sections where these are missing or unreliable. Artificial neural networks, decision tree regression, random forest regression, support vector regression and extreme gradient boosting are the most popular tools available at our disposal for making these estimations. This study has compared these different techniques for their effectiveness and accuracy in making sonic transit time predictions based on other available well logs. The obtained results suggest that despite all the attention on artificial neural networks, eXtreme gradient boosting and the random forest regression outperform it for the given purpose. In the case of missing shear transit time data, random forest regression made predictions with a root mean squared error of 1.03 × 10–4 and a root mean squared error of 0.97 while eXtreme gradient boosting regression did so with a root mean squared error of 1.36 × 10–4 and the same regression coefficient (0.97). When no sonic data were available, random forest regression estimated shear transit time with a root mean squared error of 6.41×10–4 and a regression coefficient of 0.95, and compressional transit time with a root mean squared error of 9.06×10–5 and a root mean squared error of 0.94. The root mean squared error of shear transit time and compressional transit time predictions made using eXtreme gradient boosting were found to be the same as those of random forest regression. The root mean squared error, however, was observed to be slightly less for the compressional transit time predictions and somewhat more for the shear transit time predictions. As data analysis, in general, is a better method for estimation than the use of empirical correlations, these machine learning‐based predictions can serve as powerful tools in the oil and gas exploration industry. [ABSTRACT FROM AUTHOR]

A significant quantity of hydrocarbons remains in the reservoir after production using primary and secondary techniques. Traditional recovery techniques produce about 33 % of the original oil in place. However, the utilization of chemicals such as surfactants and polymers facilitate the additional recovery of one‐third of this oil. Researchers are currently aiming at mixing surfactant and nanoparticles for their potential applications in petroleum industry. In this work, authors claimed to be the first to study usage of synthesized Mesoporous Silica Nanoparticles (MSN) with Sodium Dodecyl Sulphate (SDS) surfactant to understand its applicability in Chemical Enhanced Oil Recovery through evaluation of the surface tension & Interfacial tension, surfactant adsorption, contact angle, and core flooding experiments. Surface tension studies revealed a synergistic interaction between MSN and anionic surfactant molecules. With the introduction of 2500 ppm of anionic surfactant, the surface tension of deionized water reduces to 34.5 mN/m from 72.4 mN/m. The surface tension of the mixture was further lowered by ∼9.8 % with the addition of 300 ppm MSN. The Interfacial Tension results also showed the same trend. When 300 ppm of MSN was introduced, then IFT values decreases from 8.13 mN/m to 3.91 mN/m at 2500 ppm of anionic surfactant. Contact angle measurements after MSN injection went from 77.98° for SDS (2500 ppm) to 73.36°, 66.54°, and 41.95° for 100, 200, and 300 ppm of MSN, respectively. This demonstrates that the shift toward water‐wet behavior increased along with the MSN concentration. Additionally, adding 300 ppm of MSN lowered surfactant adsorption by ∼80 % at a surfactant concentration of 2500 ppm. Up to 72.27 % of the OOIP could be recovered using the chemical slug made of SDS surfactant, polymer, and MSN. The research data suggests that the MSN can increase the effectiveness of the chemical injection approach, which can be used to recover more oil. [ABSTRACT FROM AUTHOR]

Over the years, scientific community has shown immense interest in the synthesis of novel, bioactive molecules with few adverse effects. Instead of painstaking multistep synthesis with hazardous synthetic reagents, also for clinical studies, it is better to enhance the activity and tuning by structural modification of the commercial drugs based on their structural and biological properties. It is demonstrated that diclofenac (DCF) be an effective analgesic and anti‐pyretic in the treatment of cancer‐related pain, but it has limitations and adverse effects as gastrointestinal irritation, small intestine damage, nausea, platelet dysfunction, and vertigo. Wherefore the main objective of the current research is to investigate new, novel, green methods of preparation of DCF derivatives, and structural characterization with the help of FT‐IR, UV‐Visible spectroscopy, MS spectrometry techniques. [ABSTRACT FROM AUTHOR]

The solid polymer electrolytes (SPE) based electrochemical devices are an area of attention for more than two decades. The ability of thin‐film preparation and leakage proof over the liquid counterpart are the key factors of SPE. In the present work, two different compositions, 80–20 and 85–15, of PVA:KI has been used as a host polymer complex. Where further 10 wt% of p‐Si dispersed with PVA:KI complexes. Polymer films have been prepared with standard solution cast techniques, which are further characterized for their electrical conductivity by Electrical Impedance Spectroscopy (EIS). Also, the humidity effect on the ionic conductivity of these thin films is calculated. It is observed that the ionic conductivity of these polymer electrolytes films increases with 58%, 74%, and 89% humidity. To understand the change in this ionic conductivity, the concentration and mobility of ions are also calculated, and it is found that the change in conductivity are predominately influenced due to the mobility of charge carriers. [ABSTRACT FROM AUTHOR]

Surfactant flooding is a prolific enhanced oil recovery technique. It alters the rock fluid interfacial interactions between reservoir fluids and rocks. However, a pair of impeding factors often limit the economic viability of the process and need to be optimized. The first is the surfactant loss on the adsorbent surface due to adsorption making it a potential environmental problem. The second is the Critical Micelle Concentration (CMC) which governs the amount of surfactant pumped. This study aimed to minimize the surfactant loss and the CMC, thereby optimizing the flooding efficiency and reducing the environmental concerns for nanoparticle applications. To achieve this, Silicon Carbide nanoparticles (SCN) were employed as additives to the surfactant solution. It was observed that the use of SCN reduces the surfactant adsorption by as much as 44 % and the critical micelle concentration by 14 %. The studies also observed that the concentration of SCN required to get these results is dramatically (more than 25 times) lower than previously reported literature on other nanoparticles. To adsorption isotherm studies provide an insight into the type of adsorption taking place. The adsorption isotherm follows the Langmuir model. [ABSTRACT FROM AUTHOR]

Objective: Enrollment of patients of Black African ancestry with systemic lupus erythematosus (SLE) in phase II and phase III of the belimumab trials was not reflective of the racial distribution observed in the lupus population. This study was undertaken to assess the efficacy and safety of intravenous (IV) belimumab plus standard therapy in patients of self‐identified Black race. Methods: EMBRACE (GSK Study BEL115471; ClinicalTrials.gov identifier: NCT01632241) was a 52‐week multicenter, double‐blind, placebo‐controlled trial in adults of self‐identified Black race with active SLE who received monthly belimumab 10 mg/kg IV, or placebo, plus standard therapy. The optional 26‐week open‐label extension phase included patients who completed the double‐blind phase. The primary end point of the study was SLE Responder Index (SRI) response rate at week 52 with modified proteinuria scoring adapted from the SLE Disease Activity Index 2000 (SLEDAI‐2K) (SRI–SLEDAI‐2K). Key secondary end points included SRI response rate at week 52, time to first severe SLE flare, and reductions in prednisone dose. Results: The modified intent‐to‐treat population comprised 448 patients, of whom 96.9% were women and the mean ± SD age was 38.8 ± 11.42 years. The primary end point (improvement in the SRI–SLEDAI‐2K response rate at week 52) was not achieved (belimumab 48.7%, placebo 41.6%; odds ratio 1.40 [95% confidence interval 0.93, 2.11], P = 0.1068); however, numerical improvements favoring belimumab were observed, in which the SRI–SLEDAI‐2K response rates were higher in those who received belimumab compared with those who received placebo, especially in patients with SLE who had high disease activity or renal manifestations at baseline. The safety profile of belimumab was generally consistent with that observed in previous SLE trials. Adverse events were the primary reasons for double‐blind phase withdrawals (belimumab 5.4%, placebo 6.7%). Conclusion: The primary end point of this study was not achieved, but improvement with belimumab versus placebo was observed, suggesting that belimumab remains a suitable treatment option for SLE management in patients of Black African ancestry. [ABSTRACT FROM AUTHOR]