Versatile carbon supported mono and bimetallic nanocomposites: synthesis,characterization and their potential application for furfural reduction

Biomass conversion has been developed by testing various metal based carbon catalysts. Most of the reported catalysts either use very expensive metals or support that provides lower selectivity. In this context, we fabricated new carbon based nanocomposites and studied their catalytic application for furfural reduction – a promising biomass derived molecule. The mono (Cu, Co and Ni) and bimetallic (CuCo and CuNi) nanoparticle supported on commercial graphite (CG) were prepared and characterized by TEM, EDS, XRD and Raman spectroscopy. The analysis revealed that the nanocomposites are made up of metallic nanoparticles with average particle size of 5–13 nm on the graphite matrix. The obtained results indicated that the Cu+Ni@CG catalyst exhibited high catalytic activity for furfural reduction, thus leaving Cu+Ni as the finest and cost effective catalyst for this study.     

Imparting Multifunctionality by Utilizing Biporosity in a Zirconium‐Based Metal–Organic Framework

In this work, we have synthesized nanocomposites made up of a metal–organic framework (MOF) and conducting polymers by polymerization of specialty monomers such as pyrrole (Py) and 3,4‐ethylenedioxythiophene (EDOT) in the voids of a stable and biporous Zr‐based MOF ( UiO‐66 ). FTIR and Raman data confirmed the presence of polypyrrole ( PPy ) and poly3,4‐ethylenedioxythiophene ( PEDOT ) in UiO‐66‐PPy and UiO‐66‐PEDOT nanocomposites, respectively, and PXRD data revealed successful retention of the structure of the MOF. HRTEM images showed successful incorporation of polymer fibers inside the voids of the framework. Owing to the intrinsic biporosity of UiO‐66 , polymer chains were observed to selectively occupy only one of the voids. This resulted in a remarkable enhancement (million‐fold) of the electrical conductivity while the nanocomposites retain 60–70 % of the porosity of the original MOF. These semiconducting yet significantly porous MOF nanocomposite systems exhibited ultralow thermal conductivity. Enhanced electrical conductivity with lowered thermal conductivity could qualify such MOF nanocomposites for thermoelectric applications.     

Molecular docking,PKPD, and assessment of toxicity of few chalcone analogues as EGFR inhibitor in search of anticancer agents

In the present work, molecular docking of the chalcone analogues with receptor EGFR carried out using erlotinib as reference drug is reported. About 15 chalcone analogues were analyzed CHL(1–15). Molecules CHL2, CHL3, CHL9, CHL11, and CHL15 found strong affinity for receptor EGFR exhibiting binding energies ??7.7 kcal/mol, ??7.5 kcal/mol, ??7.6 kcal/mol, ??7.9 kcal/mol, and ??8.1 kcal/mol, respectively, when erlotinib a reference drug exhibits binding energy ??7.6 kcal/mol. Toxicity for molecules was assessed against the cytochromes P450 (CYP) and P-gp using Swiss ADMET. Molecule CHL9 could be a suitable lead compound inhibitor to CYP1A2 followed by CHL2 inhibitor of CYP1A2 and CYP2C9 and CHL15 with a most stable binding affinity of ??8.1 kcal/mol, inhibiting CYP1A2, CYP2C19, and CYP2D6. CHL3 has a binding affinity of ??7.5 kcal/mol, inhibiting all the 05 CYP enzymes (CYP1A2, CYP2C19, CYP2C9, CYP2D6, and CYP3A4). CHL11 has a binding affinity of ??7.9 kcal/mol, inhibiting CYP1A2, CYP2C19, and CYP2C9. Considering inhibition of CYP family enzymes by molecules, further here we have perform the enrichment analysis to these CYP family enzymes and reported the metabolic pathways which were probably affected by inhibition of these enzymes using EnrichR online enrichment analysis server. The current predictions over these 15 chalcone derivatives will be needed to further investigate in vivo and in vitro conditions to identify the optimum therapeutic efficacy and least toxicity.

     

Free Radicals as a Double-Edged Sword: The Cancer Preventive and Therapeutic Roles of Curcumin

Free radicals, generally composed of reactive oxygen species (ROS) and reactive nitrogen species (RNS), are generated in the body by various endogenous and exogenous systems. The overproduction of free radicals is known to cause several chronic diseases including cancer. However, increased production of free radicals by chemotherapeutic drugs is also associated with apoptosis in cancer cells, indicating the dual nature of free radicals. Among various natural compounds, curcumin manifests as an antioxidant in normal cells that helps in the prevention of carcinogenesis. It also acts as a prooxidant in cancer cells and is associated with inducing apoptosis. Curcumin quenches free radicals, induces antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase), and upregulates antioxidative protein markers–Nrf2 and HO-1 that lead to the suppression of cellular oxidative stress. In cancer cells, curcumin aggressively increases ROS that results in DNA damage and subsequently cancer cell death. It also sensitizes drug-resistant cancer cells and increases the anticancer effects of chemotherapeutic drugs. Thus, curcumin shows beneficial effects in prevention, treatment and chemosensitization of cancer cells. In this review, we will discuss the dual role of free radicals as well as the chemopreventive and chemotherapeutic effects of curcumin and its analogues against cancer.     

Membrane Proteins Have Distinct Fast Internal Motion and Residual Conformational Entropy

The internal motions of integral membrane proteins have largely eluded comprehensive experimental characterization. Here the fast side‐chain dynamics of the α‐helical sensory rhodopsin II and the β‐barrel outer membrane protein W have been investigated in lipid bilayers and detergent micelles by solution NMR relaxation techniques. Despite their differing topologies, both proteins have a similar distribution of methyl‐bearing side‐chain motion that is largely independent of membrane mimetic. The methyl‐bearing side chains of both proteins are, on average, more dynamic in the ps–ns timescale than any soluble protein characterized to date. Accordingly, both proteins retain an extraordinary residual conformational entropy in the folded state, which provides a counterbalance to the absence of the hydrophobic effect. Furthermore, the high conformational entropy could greatly influence the thermodynamics underlying membrane‐protein functions, including ligand binding, allostery, and signaling.     

Cation exchange membranes by pre-irradiation grafting of styrene into FEP films. II. Properties of copolymer membranes

The structure and some physico-chemical properties of radiation grafted FEP-g-polystyrenesulfonic acid proton exchange membranes were studied as a function of the degree of grafting. The distribution of grafted polymer across the membrane thickness was obtained from microprobe measurements. It was found that for low levels of grafting (ca. 3%), polystyrene chains are located near the membrane surface only, and the interior of the membrane remains ungrafted. With the increasing degree of grafting, polystyrene chains were incorporated into the interior of the membrane as well. An almost homogeneous distribution of grafts in the membrane was obtained at a graft level of > 13%. The influence of the degree of grafting on membrane properties, such as ion exchange capacity, swelling, and specific resistivity was studied. Three different states of water, viz., freezing free, freezing bound, and nonfreezing water have been identified in noncrosslinked membranes. However, the nature and the amount of crosslinker had a profound influence on the states of water in a membrane. © 1996 John Wiley & Sons, Inc.     

Estimation of coefficient of variation in a weighted inverse Gaussian model

The coefficient of variation is an important parameter in many physical, biological and medical sciences. In this paper we study the estimation of the square of the coefficient of variation in a weighted inverse Gaussian model which is a mixture of the inverse Gaussian and the length biased inverse Gaussian distribution. This represents a rich family of distributions for different values of the mixing parameter and can be used for modelling various life testing situations. The maximum likelihood as well as the Bayes estimates of the parameters are obtained. These estimates are used to derive the estimates of the square of the coefficient of variation of the model under study. Several important data sets are analysed to illustrate the results. © 1996 John Wiley & Sons, Ltd.     

Conducting LB films based on metal complexes of sulphur donor ligands

Preliminary studies are reported on the film forming characteristics of compounds such as dialkyldimethylammonium-M (dmit)₂ and dialkyldimethylammonium-M (mnt)₂ where M = Ni, Pt or Pd. All materials investigated show good monolayer behaviour and deposit readily onto evaporated aluminium or gold films. This is confirmed by surface potential and FTIR measurements. The lateral conductivity of deposited films increases by many orders of magnitude when exposed to bromine vapour.     

Crystal and Molecular Structure of Tosyl Pyrrolidine-2-Methanol (C12H17SO3N)

C₁₂H₁₇SO₃N, M_r = 255.33, Orthorhombic, P2₁2₁2₁, a = 11.703(1) Å, b = 14.797(3) Å, c = 14.971(2) Å, V = 2592.52 ų, Z = 8, D_m = 1.309 Mgm⁻³, D_c = 1.308 Mgm⁻³, mμ = 21.57 cm⁻¹, F(000) = 1088, T = 290 K, final R = 0.080 for 2416 unique reflections. There are two crystallographically independent molecules in the unit cell of the title compound.