10 research outputs found

    FT-IR, FT-Raman and ab-initio studies of 1,3-diphenyl thiourea

    Get PDF
    The FT-IR and FT-Raman spectra of 1,3-diphenyl thiourea were recorded and analyzed. The vibrational wavenumbers were examined theoretically with the aid of the Gaussian03 package of programs using the HF/6-311++G(d,p) and B3LYP/6-311++G(d,p) levels of theory. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands obtained in IR and Raman spectroscopy of the studied molecule. The first hyperpolarizabililty, infrared intensities and Raman activities are reported. The calculated first hyperpolarizability is comparable with the reported values of similar derivatives and is an attractive object for future studies of non-linear optics. The geometrical parameters of the title compound are in agreement with the values of similar structures. The changes in the C-N bond lengths suggest an extended π-electron delocalization over the thiourea moiety which is responsible for the non-linearity of the molecule

    Proceedings of International Web Conference in Civil Engineering for a Sustainable Planet

    No full text
    This proceeding contains articles of the various research ideas of the academic community and practitioners accepted at the "International Web Conference in Civil Engineering for a Sustainable Planet (ICCESP 2021)". ICCESP 2021 is being Organized by the Habilete Learning Solutions, Kollam in Collaboration with American Society of Civil Engineers (ASCE), TKM College of Engineering, Kollam, and Baselios Mathews II College of Engineering, Kollam, Kerala, India. Conference Title: International Web Conference in Civil Engineering for a Sustainable PlanetConference Acronym: ICCESP 2021Conference Date: 05–06 March 2021Conference Location: Online (Virtual Mode)Conference Organizer: Habilete Learning Solutions, Kollam, Kerala, IndiaCollaborators: American Society of Civil Engineers (ASCE), TKM College of Engineering, Kollam, and Baselios Mathews II College of Engineering, Kollam, Kerala, India

    Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

    Get PDF
    Background Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications. Methods We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC). Findings In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683–0·717]). Interpretation In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required. Funding British Journal of Surgery Society
    corecore