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Computational chemistry calculations are broadly useful for guiding the atom-scale design of hard–soft material interfaces including how molecular interactions of single-component liquid crystals (LCs) at inorganic surfaces lead to preferred orientations of the LC far from the surface. The majority of LCs, however, are not single-component phases but comprise of mixtures, such as a mixture of mesogens, added to provide additional functions such as responsiveness to the presence of targeted organic compounds (for chemical sensing). In such LC mixtures, little is understood about the near-surface composition and organization of molecules and how that organization propagates into the far-field LC orientation. Here, we address this broad question by using a multiscale computational approach that combines density functional theory (DFT)-based calculations and classical molecular dynamics (MD) simulations to predict the interfacial composition and organization of a binary LC mixture of 4′-cyano-4-biphenylcarbolxylic acid (CBCA) and 4′-n-pentyl-4-biphenylcarbonitrile (5CB) supported on anatase (101) titania surfaces. DFT calculations determine the surface composition and atomic-scale organization of CBCA and 5CB at the titania surface, and classical MD simulations build upon the DFT description to describe the evolution of the near-surface order into the bulk LC. A surprising finding is that the 5CB and CBCA molecules adopt orthogonal orientations at the anatase surface and that, above a threshold concentration of CBCA, this mixture of orientations evolves away from the surface to define a uniform far-field homeotropic orientation. These results demonstrate that molecular-level knowledge achieved through a combination of computational techniques permits the design and understanding of functional LC mixtures at interfaces.

We investigated the temperature dependence of the intermolecular dynamics, including intermolecular vibrations and collective orientational relaxation, of one of the most typical deep eutectic solvents, reline, using femtosecond Raman-induced Kerr effect spectroscopy (fs-RIKES), subpicosecond optical Kerr effect spectroscopy (ps-OKES), and molecular dynamics (MD) simulations. According to fs-RIKES results, the temperature-dependent intermolecular vibrational band peak at ∼90 cm–1exhibited a redshift with increasing temperature. The density-of-state (DOS) spectrum of reline by MD simulations reproduced this fs-RIKES spectral feature. The decomposition analysis of the DOS spectra showed that all constituent components, including urea, cholinium cation, and chloride anion, also exhibited similar magnitudes of redshifts upon heating, indicating that the three species intermolecularly interact one another. The temperature sensitivity of the intermolecular vibrational frequency was high compared to that of ionic liquids. According to ps-OKES results, the slow orientational relaxation rate increased with increasing temperature; however, this phenomenon was not well explained by the Stokes–Einstein–Debye hydrodynamic model. Analysis of the orientational relaxation time based on the Stokes–Einstein–Debye model indicates that the decoupling between the orientational relaxation time and viscosity occurs at temperatures below ∼330 K. Quantum chemistry calculations of urea and the cholinium cation based on the MP2/6-311++G(d,p) level of theory confirmed that the contribution of intramolecular vibrational bands to low-frequency bands below 200 cm–1was minimal. The densities, viscosities, electrical conductivities, and surface tensions of reline at various temperatures were also estimated and compared with the dynamics data.

Hemophilia A is a hereditary bleeding disorder due to coagulation factor VIII deficiency. Septic arthritis is in itself a dreaded infective condition of the joint. It is much more common in hemophilia patients than the general population and is associated with considerably higher morbidity. It presents as a difficult clinical and therapeutic problem, necessitating prompt diagnosis and intensive therapy. There was under-diagnosis of blood coagulation disorders in developing countries like India which has improved in the present time. But there is still considerable uncertainty about proper management guidelines, protocols and resources settings for treating this complication in hemophilia patients. Hereby we present a case of a 9-year-old hemophilia A patient with septic arthritis of knee joint treated at a tertiary hospital centre with available present recommended guidelines in literature, and stress upon the necessity of further formulating and improvising management guidelines for treatment and prevention of this complication in Hemophilia.

Achyranthes asperaL. (Prickly Chaff flower) is an imperative Asian herb that has been known for numerous healing powers. The aim of this research is to investigate the pharmacological i.e., antidepressant and anxiolytic properties of the methanol extract of aerial part of A. aspera(MEAA) by in vivo and in silico approaches. Additionally, thrombolytic potential of the crude extract has also been explored. The antidepressant and anxiolytic investigations were performed by force swimming test (FST), tail suspension test (TST), and hole board test (HBT) in mice, whereas clot lysis activity test was conducted using thrombolytic experimental method. Furthermore, in silico studies were appraised with Discovery studio, PyRx, UCSF Chimera whereas, PASS prediction, and ADME/T was implemented using online tools. Treatment with MEAA revealed significant (p< 0.05) reduction of immobility time in FST and TST, increased head dipping and decreased the latency of time in HBT. Besides, MEAA produced significant (p< 0.001) clot lysis activity at a minimum dose. In the computer-aided approach, among all the proteins, the docking score has been revealed ranging from − 2.31 kcal/mol to − 7.4 kcal/mol. Spathulenol, diazepam and hydroquinone showed the best binding affinity and all compounds were found safe in ADME/T study. The outcomes of this research demonstrate that MEAA may provide potential for mitigating depression, anxiety, and coagulation.

In 1992, Blasco considered a weighted Bergman space using Dini-weight function. He proved that a linear operator Ton weighted Bergman space to any Banach space Xis bounded if and only if certain one parameter fractional derivative of a single X-valued analytic function satisfy some growth condition. In this paper, we use a three parameters fractional derivative of a single X-valued analytic function and provide an equivalent condition. Our technique uses the Gaussian hypergeometric functions. Furthermore we supply some conditions on the parameters a, band cunder which the Gaussian hypergeometric functions F(a, b; c; z) are Dini-weight.

The main purpose of this paper is to find necessary and sufficient conditions of coefficient multipliers from $$H(p,q,\varphi _1)$$ H(p,q,φ1) to $$H(s,t,\varphi _2)$$ H(s,t,φ2) spaces for certain ranges of the parameters p, q, s, t. We also find the sufficient conditions for coefficient multipliers on $$H(p,q,\alpha )$$ H(p,q,α) by making use of the Gaussian hypergeometric functions F(a, b; c; z). Our results generalizes some well known results of Jevtić, Pavlović, Duren and Shields, Ohya, Shimizu and Watanabe.

Let fbe an analytic function on the unit disc $${\mathbb{D}}$$Dand F(a, b; c; z) be the Gaussian hypergeometric function. We consider the operator Ta,b,con H(p, q, α) defined as Ta, b, cf(z) =  f(z) * F(a, b; c; z), where * denotes the usual Hadamard/convolution product. We prove that the Taylor coefficients of F(a, b; c; z) are a multiplier from H(p, q, α) to H(p, q, α+ a+ b− c− 1) under certain conditions on a, band c. As a consequence, we generalize some well-known results on fractional derivatives and integrals. Furthermore, we supply some conditions on a, band cunder which F(a, b; c; z) lies in H(p, q, α).

The oxidative coupling of the α‐carbon atom of aromatic ketones with unactivated arenes in the presence of selenium dioxide and p‐toluenesulfonic acid monohydrate is described. A number of unsymmetrical benzils have been prepared in good yields (38–75 %) with high regioselectivity. The generality and functional tolerance of this new protocol is demonstrated. The mechanistic pathway for the oxidative coupling reaction is also described. The reaction displays superiority in terms of minimization of steps with the C–C bond formation promoted by SeO2and pTsOH·H2O. This method is advantageous as the reactants used as the solvent can be recovered.

Purpose:A study was carried out in an Indian teaching hospital in 2009 to detect the rate of surgical site infections (SSI) and peripheral vascular access site infections. Materials and Methods:The study was a point-prevalence study involving over 300 patients. The presence of infection was determined according to the CDC criteria. Swabs were taken from the infected sites and identification and sensitivity were carried out using VITEK® 2 automated system. Characterisation of β-lactamase was carried out at ARRML, Colindale, London. Results:The rate of SSI was 15% for the clean and clean-contaminated categories while that for the dirty contaminated category was 85% (NNIS risk index 0). Cultures yielded definite or probable pathogens from 64% (9/14) of the patients with SSI. In 1/3rdof the cultures, Staphylococcus aureuswas grown and the rest had Enterobacteriaceae, either extended-spectrum β-lactamase (ESBL) producers or Amp-C hyperproducers and, alarmingly, three isolates were positive for newly recognised New Delhi metallo-β-lactamase-1 (NDM-1). In medicine, 87% (n= 99) of the patients had a peripheral IV access device, 55% developed associated phlebitis/infection and, in seven, probable pathogens were isolated (Candida species and Escherichia coliproducing ESBL and NDM-1, respectively, Staphylococcus aureus and Enterococcus faecium). All ESBL and metallo-β-lactamase producers were resistant to multiple classes of antimicrobials, the latter being sensitive only to colistin and tigecycline. The study also found that all post-operative patients were on antibiotics, 92% on IV [213 defined daily doses (DDD)/100 post-op patients] limited mainly to the third-generation cephalosporins (26%) and aminoglycosides (24%) and imidazole derivatives (30%). In medicine, 83% (n= 82) were on IV antibiotics (123 DDD/100 bed-days), limited mainly to the third-generation cephalosporins (74%). Conclusion:Indiscriminate use of antibiotics is a major problem predisposing patients to harm by multi-resistant pathogens. Carbapenems were in little use in this hospital, but the selection pressure exerted by cephalosporins and other unrelated classes was sufficient to select NDM-1-producing strains due to co-selection, suggesting a role of single plasmid carrying resistance genes to multiple classes.

We report here temperature-dependent (293 ≤ T(K) ≤ 336) dielectric relaxation (DR) measurements of (acetamide + LiBr/NO3–/ClO4–) deep eutectic solvents (DESs) in the frequency window of 0.2 ≤ ν (GHz) ≤ 50 and explore, via molecular dynamics simulations, the relative roles for the collective single-particle reorientational relaxations and the H-bond dynamics of acetamide in the measured DR response. In addition, DR measurements of neat molten acetamide were performed. Recorded DR spectra of these DESs require multi-Debye fits and produce well-separated DR time scales that are spread over several picoseconds to ∼1 ns. Simulations suggest DR time scales derive contributions from both the collective reorientational (Cl(t)) relaxation and structural H-bond (CHB(t)) dynamics of acetamide. A good correlation between the measured and simulated activation energies further reveals a strong connection between the measured DR and the simulated Cl(t)and CHB(t). Average DR times exhibit a strong fractional viscosity dependence, suggesting substantial microheterogeneity in these media. Simulations of Cl(t)and CHB(t) reveal strong stretched exponential relaxations with a stretching exponent, 0.4 ≤ β ≤ 0.7. The ratio between the average reorientational correlation times of first and second ranks, ⟨τ⟩l=1/⟨τ⟩l=2, deviates appreciably from Debye’s l(l+1)law for homogeneous media. Importantly, a pronounced translation-rotation decoupling between the simulated reorientation and center-of-mass diffusion times was observed.

Molecular dynamics simulations and dielectric relaxation (DR) measurements in the frequency window, 0.2 ≤ ν/GHz ≤ 50, have been performed to explore the heterogeneous reorientation dynamics in [fcholine chloride + (1 – f) urea] deep eutectic solvents (DESs) at f= 0.33 and 0.40 in the temperature range 293 ≤ T/K ≤ 333. The solution viscosity varies by more than an order of magnitude. DR measurements in these DESs reveal multiple relaxation timescales—τ1∼ 500 ps, τ2∼ 100 ps, τ3∼ 30 ps, and τ4∼ 5 ps. Simulated rank-dependent collective single-particle reorientational (Cl(t), lbeing the rank) and structural H-bond [CHB(t)] relaxations can explain the microscopic origin of all these DR timescales. The average DR times, ⟨τDR⟩, exhibit a pronounced fractional viscosity dependence, ⟨τDR⟩ ∝ (η/T)p, with p= 0.1. This experimental evidence of pronounced heterogeneous reorientation dynamics in these DESs is supported by a strong translation–rotation decoupling and a significant deviation of the average reorientational correlation times (⟨τl⟩) from Debye’s l(l+ 1) law. The simulated ratios between the average rotation and translation timescales for both urea and choline correctly reduce to the appropriate hydrodynamic limit at high temperatures. The stretched exponential relaxations of the simulated self-dynamic structure factors and the non-Gaussian single-particle displacement distributions further support strong temporal heterogeneity in these DESs. Dynamic susceptibilities from the simulated four-point correlations exhibit long correlated timescales. Moreover, simulated activation energies estimated from the temperature-dependent C1(t) decays and the translational diffusion coefficients from the velocity autocorrelation functions agree favorably with those from the corresponding DR and the pulsed field gradient nuclear magnetic resonance measurements.

The coupling of the α‐carbon atom of aromatic/heteroaromatic ketones with unactivated arenes proceeds with high regioselectivity.

The title compounds, e.g. (VIII) and (XIV), are prepared using benzoxazines and α‐oxoketene dithio‐acetals.

A four‐component synthesis of title compounds (IV) using L‐proline as a catalyst is established.

The mild and environmentally friendly process allows access to various highly substituted derivatives of the pharmaceutically important title scaffold.

The deprotection is successfully achieved under conditions A) in EtOH/water to give the corresponding aldehydes and ketones in high yields.