Analytic ab initio-based molecular interaction potential for the BrO·H\u3csub\u3e2\u3c/sub\u3eO complex

Radical halogen oxide species play important roles within atmospheric processes, specifically those responsible for the removal of O3. To facilitate future investigations on this family of compounds, RCCSD(T)/aug-cc-pVQZ-level electronic structure calculations were employed to generate individual-molecule optimized geometries, as well as to determine the global minimum energy structure for the BrO·H2O complex. This information facilitated the generation of several one-dimensional potential energy surface (PES) scans for the BrO·H2O complex. Scans were performed for both the ground state and the first excited state; this inclusion is due to a low-lying first electronic excited-state energy. These rigid-geometry PES scans were used both to generate a novel analytic interaction potential by modifying the existing Thole-type model used for water and to the fitted potential function. This interaction potential features anisotropic atomic polarizabilities facilitating appropriate modeling of the physics regarding the unpaired electron residing within the p-orbitals of the oxygen atom of the bromine oxide radical. The intention of this work is to facilitate future molecular dynamics simulations involving the interaction between the BrO radical and water clusters as a first step in devising possible novel chemistries taking place at the water interface of clouds within the atmosphere

Analytic ab initio-based molecular interaction potential for the BrO·H\u3csub\u3e2\u3c/sub\u3eO complex

Radical halogen oxide species play important roles within atmospheric processes, specifically those responsible for the removal of O3. To facilitate future investigations on this family of compounds, RCCSD(T)/aug-cc-pVQZ-level electronic structure calculations were employed to generate individual-molecule optimized geometries, as well as to determine the global minimum energy structure for the BrO·H2O complex. This information facilitated the generation of several one-dimensional potential energy surface (PES) scans for the BrO·H2O complex. Scans were performed for both the ground state and the first excited state; this inclusion is due to a low-lying first electronic excited-state energy. These rigid-geometry PES scans were used both to generate a novel analytic interaction potential by modifying the existing Thole-type model used for water and to the fitted potential function. This interaction potential features anisotropic atomic polarizabilities facilitating appropriate modeling of the physics regarding the unpaired electron residing within the p-orbitals of the oxygen atom of the bromine oxide radical. The intention of this work is to facilitate future molecular dynamics simulations involving the interaction between the BrO radical and water clusters as a first step in devising possible novel chemistries taking place at the water interface of clouds within the atmosphere

Rapid topography mapping of scalar fields: Large molecular clusters

The following article appeared in Journal of Chemical Physics 137.7 (2012): 074116 and may be found at http://scitation.aip.org/content/aip/journal/jcp/137/7/10.1063/1.4746243An efficient and rapid algorithm for topography mapping of scalar fields, molecular electron density (MED) and molecular electrostatic potential (MESP) is presented. The highlight of the work is the use of fast function evaluation by Deformed-atoms-in-molecules (DAM) method. The DAM method provides very rapid as well as sufficiently accurate function and gradient evaluation. For mapping the topography of large systems, the molecular tailoring approach (MTA) is invoked. This new code is tested out for mapping the MED and MESP critical points (CP's) of small systems. It is further applied to large molecular clusters viz. (H 2O) 25, (C 6H 6) 8 and also to a unit cell of valine crystal at MP26-31G(d) level of theory. The completeness of the topography is checked by extensive search as well as applying the Poincaré-Hopf relation. The results obtained show that the DAM method in combination with MTA provides a rapid and efficient route for mapping the topography of large molecular systemsAuthors thank the Center for Development of Advanced Computing (C-DAC), Pune for financial and computational support. S.R.G. is grateful to the Department of Science and Technology (DST) for the award of J. C. Bose National Fellowship. R. López acknowledges partial funding from the CAM (S2009_PPQ-1545, LIQUORGAS) and MICINN (CTQ2010-19232). Authors are also thankful to Dr. Graeme M. Day, University of Cambridge, for providing the coordinates of unit cell of valine crystal and to Dr. V. Subramanian, CLRI, Chennai for providing some test run

Transforming Growth Factor β Signaling Pathway Associated Gene Polymorphisms May Explain Lower Breast Cancer Risk in Western Indian Women

Transforming growth factor β1 (TGFB1) T29C and TGF β receptor type 1 (TGFBR1) 6A/9A polymorphisms have been implicated in the modulation of risk for breast cancer in Caucasian women. We analyzed these polymorphisms and combinations of their genotypes, in pre menopausal breast cancer patients (N = 182) and healthy women (N = 236) from western India as well as in breast cancer patients and healthy women from the Parsi community (N = 48 & 171, respectively). Western Indian women were characterized by a higher frequency of TGFB1*C allele of the TGF β T29C polymorphism (0.48 vs 0.44) and a significantly lower frequency of TGFBR1*6A allele of the TGFBR1 6A/9A polymorphism (0.02 vs 0.068, p<0.01) as compared to healthy Parsi women. A strong protective effect of TGFB1*29C allele was seen in younger western Indian women (<40 yrs; OR = 0.45, 95% CI 0.25–0.81). Compared to healthy women, the strikingly higher frequencies of low or intermediate TGF β signalers in patients suggested a strong influence of the combination of these genotypes on the risk for breast cancer in Parsi women (for intermediate signalers, OR = 4.47 95%CI 1.01–19.69). The frequency of low signalers in Parsi healthy women, while comparable to that reported in Europeans and Americans, was three times higher than that in healthy women from western India (10.6% vs 3.3%, p<0.01). These observations, in conjunction with the low incidence rate of breast cancer in Indian women compared to White women, raise a possibility that the higher frequency of TGFB1*29C allele and lower frequency of TGFBR1*6A allele may represent important genetic determinants that together contribute to a lower risk of breast cancer in western Indian women

Heterogeneity of breast cancer risk within the South Asian female population in England: a population-based case–control study of first-generation migrants

South Asian women in England have a lower breast cancer risk than their English-native counterparts, but less is known about variations in risk between distinct South Asian ethnic subgroups. We used the data from a population-based case-control study of first-generation South Asian migrants to assess risks by ethnic subgroup. In all, 240 breast cancer cases, identified through cancer registries, were individually matched on age and general practitioner to two controls. Information on the region of origin, religious and linguistic background, and on breast cancer risk factors was obtained from participants. Breast cancer odds varied significantly between the ethnic subgroups (P=0.008), with risk increasing in the following order Bangladeshi Muslims (odds ratio (OR) 0.33, 95% confidence interval (CI): 0.10, 1.06), Punjabi Hindu (OR 0.59, 95% CI: 0.33, 1.27), Gujarati Hindu (I=reference group), Punjabi Sikh (OR 1.23, 95% CI: 0.72, 2.11) and Pakistani/Indian Muslims (OR 1.76, 95% CI: 1.10, 2.81). The statistically significant raised risk in Pakistani/Indian Muslims increased with adjustment for socioeconomic and reproductive risk factors (OR 2.12, 95% CI: 1.25, 3.58), but was attenuated, and no longer significant, with further adjustment for waist circumference and intake of nonstarch polysaccharides and fat (OR 1.49, 95% CI: 0.85, 2.63). These findings reveal differences in breast cancer risk between South Asian ethnic subgroups, which were not fully explained by reproductive differences, but were partly accounted for by diet and body size

Synthesis and characterization of polystyrene-blockpoly(vinylbenzoic acid): a promising compound for manipulating photoresponsive properties at the nanoscale

"Published online: 27 January 2015"Using reversible addition-fragmentation chain transfer (RAFT) polymerization, the effect of PSt macroRAFT and 4VBA ratio on the synthesis of a carboxylic acid functional block copolymer (PSt-b-P4VBA) was studied. PSt macroRAFT polymer was initially prepared followed by the insertion of 4-vinylbenzoic acid (4VBA) monomer. The chemical structure of the diblock copolymer was confirmed by NMR and FTIR. The effect of PSt macroRAFT and 4VBA ratio on copolymerization yield and on molecular weight distribution was assessed by gel permeation chromatography. The rate of polymerization did not change as the 4VBA/PSt macroRAFT ratio increased, indicating an ideal amount of 4VBA insertion. An optimal ratio of [PSt macroRAFT]:[AIBN]:[4VBA] was 1.2:1:180. DSC and XRD confirmed the amorphous structure of homo and copolymer. Thermal stability was higher for PSt-b-P4VBA forming activated porous carbon char by dehydration, carbonization and oxidation. SEM and STEM observations showed a morphological evolution between PSt macroRAFT and the correspondent copolymer.The authors acknowledge the n-STeP-Nanostructured systems for Tailored Performance, with reference NORTE-07-0124-FEDER-000039, supported by the Programa Operacional Regional do Norte (ON.2), PEst-C/CTM/LA0025/2013 (Strategic Project-LA 25-2013-2014)

From habits of attrition to modes of inclusion: enhancing the role of private practitioners in routine disease surveillance

Background: Private practitioners are the preferred first point of care in a majority of low and middle-income countries and in this position, best placed for the surveillance of diseases. However their contribution to routine surveillance data is marginal. This systematic review aims to explore evidence with regards to the role, contribution, and involvement of private practitioners in routine disease data notification. We examined the factors that determine the inclusion of, and the participation thereof of private practitioners in disease surveillance activities. Methods: Literature search was conducted using the PubMed, Web of Knowledge, WHOLIS, and WHO-IRIS databases to identify peer reviewed and gray full-text documents in English with no limits for year of publication or study design. Forty manuscripts were reviewed. Results: The current participation of private practitioners in disease surveillance efforts is appalling. The main barriers to their participation are inadequate knowledge leading to unsatisfactory attitudes and misperceptions that influence their practices. Complicated reporting mechanisms with unclear guidelines, along with unsatisfactory attitudes on behalf of the government and surveillance program managers also contribute to the underreporting of cases. Infrastructural barriers especially the availability of computers and skilled human resources are critical to improving private sector participation in routine disease surveillance. Conclusion: The issues identified are similar to those for underreporting within the Integrated infectious Disease Surveillance and Response systems (IDSR) which collects data mainly from public healthcare facilities. We recommend that surveillance program officers should provide periodic training, supportive supervision and offer regular feedback to the practitioners from both public as well as private sectors in order to improve case notification. Governments need to take leadership and foster collaborative partnerships between the public and private sectors and most importantly exercise regulatory authority where needed

HPLC Method for Determination of Enantiomeric Purity of a Novel Respiratory Fluoroquinolone: WCK 1152

A sensitive, simple, specific, precise, accurate and rugged method for determination of enantiomeric purity of S-(-)-1-cyclopropyl-6-fluoro-1,4-dihydro-8-methoxy-7-{4-amino-3,3-dimethylpiperidin-1-yl}-4-oxo-quinoline-3-carboxylic acid hydrochloride monohydrate, WCK 1152, a new drug substance has been developed. The method is based on prederivatization of analyte to diastereomer followed by RP-HPLC using endcapped C-18 stationary phase. Column was maintained at 30°C. The UV/Vis detector was operated at 290 nm. Flow rate of the mobile phase was 1.25 ml/min. The method offers excellent separation of two enantiomers with resolution more than 4 and tailing factor less than 1.5. The method was validated for the quantification of R-(+)-enantiomer impurity, WCK 1153 in the bulk drug. Calibration curves showed excellent linearity over the concentration range of 0.1 to 1.5 mg/ml for WCK 1152 and 0.01 to 0.15 mg/ml for WCK 1153. Precision of the method was 1.13%. Limit of detection and limit of quantitation of the method for WCK 1152 were 0.0006 mg/ml and 0.0018 mg/ml and for WCK 1153 were 0.0007 mg/ml and 0.0021 mg/ml, respectively. Average recovery of the WCK 1153 in WCK 1152 was 94.4%. This method was employed in determining enantiomeric purity of clinical trial batches of WCK 1152

LC-MS/MS METHOD FOR THE SIMULTANEOUS DETERMINATION OF CEFEPIME AND TAZOBACTAM IN DOG PLASMA

A high performance liquid chromatography (HPLC) method with tandem mass spectrometric detection (MS/MS) has been developed and validated for the simultaneous quantification of cefepime and tazobactam in dog plasma. The method was developed on amide column with isocratic elution. The developed method is simple and economic in terms of sample preparation. The method is specific, sensitive, accurate, precise and robust. The method was successfully applied for pre-clinical pharmaco-kinetic studies in dogs. The Tmax was found to be 0.5 hr, the mean Cmax and AUC(0-12) displayed dose proportionate response