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Thiopurines are widely used to maintain remission in both ulcerative colitis (UC) and Crohn's disease (CD). Reported effectiveness and tolerability rates have been variable across studies. There are only sparse data in Asian population regarding the long-term efficacy and safety of thiopurines.Records of 5351 patients followed up at inflammatory bowel disease (IBD) clinic, All India Institute of Medical Sciences, New Delhi from 2004 to 2020 were evaluated retrospectively. Safety was evaluated in terms of long-term adverse events and development of malignancy.Of 5351 patients with IBD, 1093 who received thiopurine for 3 months (UC = 788 [proctitis-1.9%, left-sided colitis-44.9%,pancolitis-53.1%]CD = 305 [inflammatory-42.6%, stricturing-46.9%,fistulizing-10.5%]) were included (60.8%-male patients). Follow up and treatment duration on thiopurine were 7 (4-12) years and 39.4 ± 40.3 months, respectively, with 254 (23.2%) patients receiving thiopurines for more than 5 and 68 (6.2%) receiving for more than 10 years. Three hundred and fifty-nine (UC: 249 [31.6%]; CD: 110 [36.1%]; P = 0.1) patients developed adverse events; commonest was myelosuppression (23.4%) followed by gastrointestinal intolerance (3%), flu-like illness (1.7%), and arthralgia/myalgia (1.4%). Myelosuppression was the commonest cause of thiopurine withdrawal. No patient (including 254 patients on thiopurine for ≥ 5 years) developed lymphoma or non-melanoma skin cancer. The cumulative probability of staying free from adverse events in overall IBD cohort at 1, 2, and 5 years was 78.6%, 71.9%, and 68.4%, respectively, and this was comparable between UC and CD (P = 0.09).Long-term follow up of patients with IBD from northern India on thiopurine monotherapy demonstrated minimal risk of development of lymphoma as well as non-melanoma skin cancer.

Cu-CHA is the state-of-the-art catalyst for the Selective Catalytic Reduction (SCR) of NOx in vehicle applications. Although extensively studied, diverse mechanistic proposals still stand in terms of the nature of active Cu-ions and reaction pathways in SCR working conditions. Herein we address the redox mechanism underlying Low-Temperature (LT) SCR on Cu-CHA by an integration of chemical-trapping techniques, transient-response methods, operando UV/Vis-NIR spectroscopy with modelling tools based on transient kinetic analysis and density functional theory calculations. We show that the rates of the Reduction Half-Cycle (RHC) of LT-SCR display a quadratic dependence on CuII , thus questioning mechanisms based on isolated CuII -ions. We propose, instead, a CuII -pair mediated LT-RHC pathway, in which NO oxidative activation to mobile nitrite-precursor intermediates accounts for CuII reduction. These results highlight the role of dinuclear Cu complexes not only in the oxidation part of LT-SCR, but also in the RHC reaction cascade.

A detailed kinetic model describing the consumption of key components and productdistribution in the Fischer–Tropsch synthesis (FTS) over a 20%Co/0.5Re γ-Al2O3commercial catalyst is developed. The developed model incorporates the H2O-assisted CO dissociation mechanism developed by Rytter and Holmen and a novelapproach to product distribution modeling. The model parameters are optimizedagainst an experimental dataset comprising a range of process conditions: total pres-sure 2.0–2.2 MPa, temperature 210–230C, CO conversion range of 10%–75% andfeed with and without added water. The quality of the model fit measured in termsof mean absolute relative residuals (MARR) value is 23.1%, which is comparable to lit-erature reported values. The developed model can accurately describe both positiveand negative effects of water on the rate kinetics, the positive effect of water on thegrowth factor, temperature and syngas composition on the kinetics and product dis-tribution over a wide range of process conditions, which is critical for the design andoptimization of the Fisher–Tropsch reactors.

Frequency up-conversion (UC) emission from the Nd3+ -Yb3+ /Nd3+ -Yb3+ -Li+ co-doped gadolinium oxide (Gd2 O3 ) phosphors prepared by the solution combustion technique in the visible range have been studied by using 980 nm near infrared (NIR) laser diode excitation. The crystalline structure and formation of the cubic phase has been confirmed with the help of X-ray diffraction (XRD) studies. XRD peak shifts have been found towards the lower diffraction angle side in the case of the Nd3+ -Yb3+ -Li+ co-doped phosphors. Surface morphology and particle size information have been observed by using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Down-conversion emission study under 351 nm excitation in the visible region for the Nd3+ -Yb3+ /Nd3+ -Yb3+ -Li+ co-doped phosphors has been performed. The UC emission bands lying in the green and red region arising from the Nd3+ ions have been enhanced by ~260 times, ~113 times due to incorporation of Li+ ions in the Nd3+ -Yb3+ co-doped phosphors. Photometric characterization has been done for the Nd3+ -Yb3+ /Nd3+ -Yb3+ -Li+ co-doped phosphors. The present study suggests the capability of the synthesized phosphors in near-infrared (NIR) to visible upconverter and luminescent device applications.

Summary We investigated soil organic carbon (SOC) characteristics in three forests along a north–south transect in Sweden where these forest types cover about 69% of the landscape. There was variation in 14C ages, and the median ages ranged from about 25 to > 2500 cal BP in SOC. Although total SOC and nitrogen (N) contents decreased, stable carbon isotope and humification indices increased with depth. These progressive changes with depth and age were related to degradation. The δ13C values and specific biomarkers indicated that organic carbon was primarily from C3 plants. Biomarkers were effective in distinguishing OC input from specific sources (i.e. angiosperms, gymnosperms and grasses). A sharp decrease in biomarkers with depth indicated degradation of OC in the upper soil horizon, and limited contribution in the subsoil towards the stabilization of SOC. The sharp decrease in carbon stocks and 14C age in the soil OC pool with increasing soil depth, and quite large values for the percentage of modern carbon, suggested a decrease in SOC pools. Overall, these results showed that carbon sequestration in high latitude forests was small, and their role as potential carbon sinks needs to be reassessed. Highlights We studied soil organic carbon (SOC) characteristics in Swedish boreal and temperate forests. The decline of SOC with depth contributes little to carbon sequestration in deeper soil horizons. Soil degradation causes a decline in total carbon, nitrogen, alkanes and lignin with depth and age. The role of these forests as carbon sinks needs to be reassessed because of degradation of SOC.

Mass- and mole-based pellet models have been solved using least-squares formulation to describe the evolution of species composition, pressure, velocity, total concentration and mass diffusion fluxes in porous pellets for the steam methane reforming (SMR) process. The objective of this work has been to compare the mass- and mole-based diffusion flux models, convection and fluid velocity for the SMR process using the least-squares spectral element method (LS-SEM). The diffusion–reaction problems are computationally intensive, requiring efficient numerical methods for dealing with them. This paper presents formulation and algorithm of LS-SEM for solving multicomponent mass diffusion pellet models. The mass diffusion flux is described according to the rigorous Maxwell Stefan model. This flux may be defined either with molar- or mass-averaged velocities. The effectiveness factors have been calculated for the SMR process and compared with the literature data. The model evaluations revealed that: - The least-squares method is well-suited for solving the multicomponent mass diffusion pellet models for the SMR process, achieving exponential convergence. - Molar- and mass-based pellet models do not give fully identical results for the SMR process, since the pellet model is not completely consistent.

Mercury derivatives of substituted 1,3,4-thiadiazoles and 1,2,4-triazine have been synthesized under microwave irradiation in open vessels using a domestic microwave oven as well as in a conventional way. The reaction time could be cut down from hours to minutes employing microwaves, accompanied by marginally improved yields. The compounds show promising fungicidal activity.

5-Substituted 4-amino-3-mercapto-1,2,4-s-triazoles were synthesized from their corresponding hydrazides. Their condensation with ferrocene carboxylic acid in presence of phosphorus oxychloride under microwave irradiation afforded 3-substituted 6-ferrocenyl-1,2,4,-s-triazolo[3,4-b]-1,3,4-thiadiazoles. All new compounds were characterized on the basis of analytical and spectroscopic data. Reaction rates and yields were considerably enhanced using microwaves.

A fast, cheap and pollution free microwave assisted method for the synthesis of cephalosporin and its comparison with conventional method in terms of yield and reaction time were described.

A series of quinoline ring substituted N-(3-chloro-2-(2-fluoro-quinolin-3-yl)-4-oxo-azetidin-1-yl)-octanamides were synthesized from chloroacetyl chloride, octanoic acid, (2-fluoro-quinolin-3-yl-methylene)-hydrazides, and triethylamine using microwave irradiation as well as conventional heating. The reaction time can be brought down from hours to minutes with improved yields using microwave irradiation compared to conventional heating. The compounds were tested for their in vitro antibacterial activity against 2253-Corynebacterium rubrum, 2340-Enterobacter, 2491-Erwinia herbicola, K12-E. coli, and 2873-Z. mobilis. and found to possess activities comparable with or superior to the standard drug ampicillin.

The expeditious solventless synthesis of 3-[5′-alkyl-1′3′4-thiadiazol-2-yl]-4-phenyl/hydroxy-2-thiazolothiones is described from readily accessible 2-amino-5-alkyl-1,3,4-thiadiazoles on basic alumina that are accelerated by exposure to microwaves.

An efficient facile and solventless synthesis of 1,2,4-triazines using microwave is described. A non conventional synthetic procedure has been developed where solid inorganic support is used as energy transfer medium under microwave irradiation (MWI) which devoids hazards of solution phase reactions. The reaction time has been brought down from hours to seconds with improved yield as compared to conventional heating.

A novel synthesis of 6-fluoro-7-(5-aryl-1,3,4-thiadiazol/oxadiazol-2-yl-sulfanyl)-4-quinolone-3-carboxylic acids from 7-chloro-6-fluoro-4-quinolone-3-carboxylic acid and 5-substituted 1,3,4-thiadiazoles/oxadiazoles on basic alumina under microwave activation is described. All compounds were screened for their in vitro antibacterial activity against B. lichenformis, 2689, K. aerogens 2281, S. typhimurium 2501, E. herbicola 2491, and P. vulgaris 2027 and found to possess activities comparable to that of the standard drug norfloxacin.

The reaction of heterocyclic acids with 7-amino-cephalosporanic acid adsorbed on basic alumina under microwave irradiation afforded the N-acylated cephalosporin analogues in satisfactory yield. All compounds were tested for their antibacterial activity; some of them showed significant antibacterial properties. Cefotaxime and cephalothin were used as reference drugs.