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Properties of intramolecular H-bond (IHB) for a chemical system can affect the changes in geometrical/electronic features in the vicinity of the bridge. Substitution of an atom (H) in benzene with OH/SH groups forming IHB has little effect on its aromaticity. This report is devoted to the depiction of the effect of OH/SH substituent on stability/aromaticity of multi-substituted benzene rings via IHB formation. The computational studies on the stability/aromaticity in the homo (OH/SH) and hetero (OH and SH) substituted form of the benzene systems have been investigated using B3LYP/aug-cc-pVDZ and MP2/aug-cc-pVDZ approaches with the aid of aromaticity indices (AIs) descriptors (NICS, HOMA, AIBIC, and PDI) and IHB/stability diagnostics; relative energy, QTAIM based interaction energy acquired from the potential energy density and electron density, HBSBIC, and HOMO-LUMO gap including NCI plots. The IHBs formed by different OH/SH substituents have a vital role as an aromaticity modulator and deploying the above-said tools, it turns out that the cyclic 4n+2 I�-electrons delocalization is weakened/strengthened depending on the number and types of OH/SH substituents forming the IHBs. Here, all the AIs vary in a small amount and indicative of the modulator of the I�-electron structure to the substituent effect via IHB formation. As in practical applications, the diagnostics based on different criteria do not speak with the same voice, hence interestingly, in many cases, the changes in AIs notably correlate with their stability. © 2021 Wiley-VCH GmbH

This work presents the synthesis and characterization as well as crystal structure determination of a biologically relevant, chemically and medicinally interesting isolated solids-state crystal structure of its ethanol inclusion compound, 2-(5,5-dimethyl-3-oxocyclohex-1-en-1-yl) Hydrazinecarbothioamide for the first time in the literature. The molecules pack itself in the crystal lattices via intermolecular interactions. The stability due to the role of H-bond(s) in the title compound and its packed cell, were quantitatively investigated by topological analysis based on Bader′s quantum theory of atoms in molecules (QTAIM) to characterize these interactions. The chemical, as well as topological properties of the electron densities, ρ(r) of the title system and its packed cell have been studied using DFT approach. Chemical reactivity of both species has also been calculated using HOMO-LUMO, ionization energy, hardness, and chemical potential along with their molecular electrostatic potential and total electron density plots. In order to gain better insight into the role of H-bonding interaction(s), the theoretically investigated binding energies revealed that crystal within the lattice unit (packed cell) having more intermolecular stabilizing interactions has been found to be more stable than its molecular unit using DFT method and ab initio modeling which is fairly supported by the experimentally predicted H-bonding interaction(s) and QTAIM based topological parameters.

In this article, we describe a discontinuous finite volume method with interpolated coefficients for the numerical approximation of the distributed optimal control problem governed by a class of semilinear elliptic equations with control constraints. The proposed distributed control problem involves three unknown variable: control, state and costate. For the approximation of control, we have adopted three different methodologies: variational discretization, piecewise constant and piecewise linear discretization, while the approximation of state and costate variables is based on discontinuous piecewise linear polynomials. As the resulted scheme is non-symmetric, optimize-then-discretize approach is used to approximate the control problem. Optimal a priori error estimates in suitable natural norms for state, costate and control variables are derived. Moreover, numerical experiments are presented to support the derived theoretical results. © 2017 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2017

A proof-of-concept design for autonomous, self-propelling motors towards value-added product synthesis and separation is presented. The hybrid motor design consists of two distinct functional blocks. The first, a sodium borohydride (NaBH4 ) granule, serves both as a reaction prerequisite for the reduction of vanillin and also as a localized solid-state fuel in the reaction mixture. The second capping functional block consisting of a graphene-polymer composite serves as a hydrophobic matrix to attract the reaction product vanillyl alcohol (VA), resulting in facile separation of this edible value-added product. These autonomously propelled motors were fabricated at a length scale down to 400 μm, and once introduced in the reaction environment showed rapid bubble-propulsion followed by high-purity separation of the reaction product (VA) by the virtue of the graphene-polymer cap acting as a mesoporous sponge. The concept has excellent potential towards the synthesis/isolation of industrially important compounds, affinity-based product separation, pollutant remediation (such as heavy metal chelation/adsorption), as well as localized fuel-gradients as an alternative to external fuel dependency.

An innovative concept for the fabrication of dual-action microrobots capable of performing single-cell microsurgery along with a site-directed drug-delivery feature is presented. These multi-action plant-derived biocompatible "medibots" can play a pivotal role in understanding micromotor interactions at the cellular level, aiming toward the destruction of harmful cells (like cancer) among others in living systems.

A series of neodymium(III) and samarium(III) complexes of type [Ln(L)Cl(H2O)3] have been synthesized with Schiff bases (LH2) derived from 3-(phenyl/substituted phenyl)-4-amino-5-mercapto-1,2,4-triazoles and isatin. The structures of the complexes were established using elemental analysis, molar conductivities, magnetic moments, infrared, NMR (1H, 13C) and UV–visible spectra, X-ray diffraction and mass spectrometry. The thermal behaviour of these compounds under non-isothermal conditions was investigated using thermogravimetry and differential thermogravimetry. The intermediates obtained at the end of various thermal decomposition steps were identified from elemental analysis and infrared spectral studies. All the ligands and their complexes were also screened for their antibacterial activity against Staphylococcus aureus and Bacillus subtilis and antifungal activity against Aspergillus niger, Aspergillus flavus and Colletotrichum capsici. The screening results were correlated with the structural features of the compounds. Copyright © 2015 John Wiley & Sons, Ltd.

Loeys-Dietz syndrome (LDS) is a connective tissue disorder characterized by vascular and skeletal abnormalities resembling Marfan syndrome, including a predisposition for pathologic fracture. LDS is caused by heterozygous mutations in the genes encoding transforming growth factor-β (TGF-β) type 1 and type 2 receptors. In this study, we characterized the skeletal phenotype of mice carrying a mutation in the TGF-β type 2 receptor associated with severe LDS in humans. Cortical bone in LDS mice showed significantly reduced tissue area, bone area, and cortical thickness with increased eccentricity. However, no significant differences in trabecular bone volume were observed. Dynamic histomorphometry performed in calcein-labeled mice showed decreased mineral apposition rates in cortical and trabecular bone with normal numbers of osteoblasts and osteoclasts. Mechanical testing of femurs by three-point bending revealed reduced femoral strength and fracture resistance. In vitro, osteoblasts from LDS mice demonstrated increased mineralization with enhanced expression of osteoblast differentiation markers compared with control cells. These changes were associated with impaired TGF-β1-induced Smad2 and Erk1/2 phosphorylation and upregulated TGF-β1 ligand mRNA expression, compatible with G357W as a loss-of-function mutation in the TGF-β type 2 receptor. Paradoxically, phosphorylated Smad2/3 in cortical osteocytes measured by immunohistochemistry was increased relative to controls, possibly suggesting the cross-activation of TGF-β-related receptors. The skeletal phenotype observed in the LDS mouse closely resembles the principal structural features of bone in humans with LDS and establishes this mouse as a valid in vivo model for further investigation of TGF-β receptor signaling in bone.

A novel series of nano-sized Zn(II) macrocyclic complexes has been synthesized using the template method, i.e. by the in situ reaction of Schiff bases (derived from 1,4-bis(4-amino-5-mercapto-1,2,4-triazol-3-yl)alkanes/phenylene with salicylaldehyde/2-hydroxyacetophenone) and 1,4-dibromobutane in the presence of zinc(II) acetate dihydrate in ethanol. The complexes have been characterized using elemental analysis, infrared and NMR spectroscopies, scanning electron microscopy and thermal analysis. The catalytic properties of these complexes have been investigated kinetically for the hydrolysis of p-nitrophenylacetate (PNPA) at 25°C in aqueous dimethylsulfoxide using phosphate buffer (pH = 7.0–8.5). During the reaction, absorbance of p-nitrophenolate increases linearly with time (i.e. increase of p-nitrophenolate concentration) which indicates that the rate of the reaction increases linearly with time. On the basis of these results, a plausible mechanism for the hydrolysis of PNPA is proposed. It is shown that coordinated water may serve as a good nucleophile that effectively catalyses PNPA hydrolysis. Therefore, these complexes may serve as model compounds for hydrolytic enzymes. Copyright © 2014 John Wiley & Sons, Ltd.

A series of 3-[3-substituted-5-mercapto-1,2,4-triazol-4-yl]-spiro-(indan-1′,2-thiazolidin)-4-ones were designed for the purpose of searching for novel antimicrobial agents and have been synthesized conveniently in a single step with a three-component protocol in polyethylene (400) as green reaction media. Thus, the condensation reaction between indane-1-one; 4-amino-5-mercapto-1,2,4-triazoles and mercaptoacetic acid in polyethylene glycol (400) gave quantitatively and analytically pure titled compounds . The structure of synthesized compound is based on spectral (IR, 1H-NMR, and 13C-NMR) as well elemental analyses. These compounds have been screened for their antibacterial, antifungal, and antitubercular activities. Some of them have showed significant inhibition on fungal and bacterial growth and antitubercular activity against Mycobacterium tuberculosis. The compounds , , and display antifungal activity against Candida albicans [minimum inhibitory concentration (MIC) 3.13, 6.25 µg/mL] and antibacterial activity against Streptococcus pneumoniae (MIC 3.13 µg/mL) of the order of standard drugs tested under similar conditions, and compound showed better antitubercular activity than other compounds against M. tuberculosis (H37Rv strain, MIC 12.5 µg/mL).

Osteogenesis imperfecta type VI (OI type VI) has recently be linked to a mutation in the SERPINF1 gene, which encodes pigment epithelium-derived factor (PEDF), a ubiquitously expressed protein originally described for its neurotrophic and antiangiogenic properties. In this study, we characterized the skeletal phenotype of a mouse with targeted disruption of Pedf. In normal mouse bone, Pedf was localized to osteoblasts and osteocytes. Micro-computed tomography (µCT) and quantitative bone histomorphometry in femurs of mature Pedf null mutants revealed reduced trabecular bone volume and the accumulation of unmineralized bone matrix. Fourier transform infrared microscopy (FTIR) indicated an increased mineral:matrix ratio in mutant bones, which were more brittle than controls. In vitro, osteoblasts from Pedf null mice exhibited enhanced mineral deposition as assessed by Alizarin Red staining and an increased mineral:matrix determined by FTIR analysis of calcified nodules. The findings in this mouse model mimic the principal structural and biochemical features of bone observed in humans with OI type VI and consequently provide a useful model with which to further investigate the role of PEDF in this bone disorder.

An inversion technique is proposed to reconstruct an elevated point emission source of known height of atmospheric trace species from a finite number of concentration measurements in low-wind stable conditions. Observations from the SF6 diffusion experiment at Idaho National Engineering Laboratory in low-wind stable conditions are used for the point source reconstruction. The source location and its strength are both retrieved exactly with the model-generated measurements in all the runs. With real data, the location is reconstructed with an average error of 20 m, mostly along the wind, and the intensity is retrieved within a factor of 2 in all the runs. The incurred errors in the retrieval are justified by estimating the angular departure between the vectors of measurement and adjoint function. A sensitivity study is carried out to analyse the sensitivity of the source estimation with respect to signal perturbation caused by the background concentration of the species in the ambient air. Source reconstruction is shown to be improved and more focused when the samplers having a measurement value corresponding to the background concentration are maintained in the inversion process. Copyright © 2012 Royal Meteorological Society

The interaction between leukocytes and the vascular endothelial cells (EC) via cellular adhesion molecules plays an important role in the pathogenesis of various inflammatory and autoimmune diseases. Small molecules that block these interactions have been targeted as potential therapeutic agents against acute and chronic inflammatory diseases. In an effort to identify potent intercellular cell adhesion molecule-1 (ICAM-1) inhibitors, a large number of arylalkyl ketones, benzophenones, desoxybenzoins and chalcones and their analogs (54 in total) have been synthesized and screened for their ICAM-1 inhibitory activity. The structure-activity relationship studies of these compounds identified three potent chalcone derivatives and also demonstrated the possible mechanism for their ICAM-1 inhibitory activities. The most active compound was found to be 79.

The incompressible miscible displacement problem in porous media is modeled by a coupled system of two nonlinear partial differential equations, the pressure-velocity equation and the concentration equation. In this article, we present a mixed finite volume element method for the approximation of pressure-velocity equation and a discontinuous Galerkin finite volume element method for the concentration equation. A priori error estimates in L∞(L2) are derived for velocity, pressure, and concentration. Numerical results are presented to substantiate the validity of the theoretical results. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2012

A proof-of-concept for the fabrication of genetically customizable biogenic materials for photovoltaic applications is presented. E. coli is first genetically engineered to heterologously express the carotenoid biosynthetic pathway from plants. This modification yields a strain that overproduces the photoactive pigment lycopene. The pigment-producing cells are then coated with TiO2 nanoparticles via a tryptophan-mediated supramolecular interface, and subsequent incorporation of the resulting biogenic material (cells@TiO2 ) as an anode in an I- /I3- -based dye-sensitized solar cell yields an excellent photovoltaic (PV) response. This work lays strong foundations for the development of bio-PV materials and next-generation organic optoelectronics that are green, inexpensive, and easy to manufacture.

In this article, a one parameter family of discontinuous Galerkin finite volume element methods for approximating the solution of a class of second-order linear elliptic problems is discussed. Optimal error estimates in L2 and broken H1- norms are derived. Numerical results confirm the theoretical order of convergences. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009

SUMMARY In this study, a series of shaking table tests are carried out on scaled models of two seismically isolated highway bridges to investigate the eect of rocking motion and vertical acceleration on seismic performance of resilient sliding isolators. In addition, performance of RSI is compared with system having solely natural rubber bearings. Test results show that variation of normal force on sliders due to rocking eect and vertical acceleration makes no signicant dierence in response of RSI systems. In addition, analytical response of prototype isolated bridge and the model used in experiments is obtained analytically by using non-linear model for isolation systems. It is observed that for seismically isolated bridges, dynamic response of full-scale complex structures can be predicted with acceptable accuracy by experiments using a simple model of the structure. Copyright ? 2005 John Wiley & Sons, Ltd.