12 research outputs found

    Investigation of the Experimental and Theoretical Release of Caffeine from Cosmetic Hydrogels and Patches

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    Molecular docking (MD) is a tool that performs computational simulation. In the systems such as solutions, gels, and creams, it can be used to predict types of chemical interactions by calculating binding energies of temporary created complexes between the molecules. This study explores experimental (IVRT) and theoretical (MD) release of caffeine from six different cosmetic hydrogels and patches. The aim of the study was to compare the experimental and theoretical data and determine whether MD can be used as a tool to predict the release of caffeine

    MULTI-CRITERIA ASSESMENT OF THE SMART GRID EFFICIENCY USING THE FUZZY ANALITICAL HYERARCHY PROCESS

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    In this paper, the key performance indicators related to the smart grid efficiency, as the key factor of any energy management system implementation have been analysed. The authors are proposing multi-criteria fuzzy AHP methodology for the determination of overall smart grid efficiency. Four criteria (technology, costs, user satisfaction, and environmental protection) and seven performances (according to EU and US initiatives for analysis of benefits and effects of smart grid systems) for the selection of optimal smart grid project are defined. The analysis shows that the dominant performances of the optimal smart grid project are efficiency, security and quality of supply. The methodology is illustrated on the choice of smart grid development strategy for the medium size power distribution company

    Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

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    PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

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    PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Recovery of Vanadium (V) Oxyanions by a Magnetic Macroporous Copolymer Nanocomposite Sorbent

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    An amino-functionalized magnetic macroporous copolymer of glycidyl methacrylate (GM) and ethylene glycol (E) dimethacrylate (m-poly(GME)-deta) was synthesized, fully characterized, and used to investigate the adsorption of vanadium (V) oxyanions from aqueous solutions (Ci = 0.5 mM) in a batch system at room temperature (298 K). Pseudo-first-order (PFO), pseudo-second-order (PSO), Elovich, and intra-particle diffusion (IPD) models were used to analyze the kinetic data. The study showed that sorption is rapid, i.e., the sorption half-time is approximately one minute. Initially, the sorption process primarily involved surface sorbent particles, and it was best described by the PSO model. However, after saturation of the surface active sites is attained, the sorption rate decreases significantly because of limitations of the diffusion rate, which is then primarily controlled by the IPD process. The sorption process is favorable in the pH range of 3-6 due to the strong electrostatic interactions between the absorption centers of copolymer and vanadium (V) oxyanions. In the stated pH range, deta absorption centers with two and three protonated N atoms are in equilibrium as studied by quantum chemical modeling. Among V(V) species present in diluted aqueous media, the adsorption of H2VO4- ions dominates

    On the photophysical properties of a liquid crystal dimer based on 4-nitrostilbene: A combined experimental and theoretical study

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    A new liquid crystal dimer, 1,12-bis(4-(2-(4-nitrophenyl)ethenyl)phenoxy)dodecane, was synthesized and structurally characterized. The compound exhibited enantiotropic nematic phase. The spectroscopic properties were analysed by UV-Vis and fluorescence techniques. Theoretical calculations were used to predict the UV-Vis spectral properties of three isomers and propose a mechanism of conversion between them. The obtained results present a solid basis for the future studies on the stilbene-based liquid crystal dimers, thus affording guidelines for development of a structure-property relationship of these compounds

    Supramolecular Perspective of Coordination Effects on Fluorine Interactions

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    Coordination effects have been considered through the most common interactions in the crystal structures of fluoro compounds (C-H/F and F/F interactions). The supramolecular profile of these effects is based on quantum-chemical calculations for the assessment of the interaction strength and electrostatic potential maps, which provide a qualitative insight into the examined effect. Coordination of aliphatic fluorides leads to an increase of the negative potential of the F atoms, and, hence, an increase in the hydrogen-bonding acceptor ability (strengthening of C-H/F interactions) and a weakening of the F/F interactions, due to an increase in repulsive interactions between the F atoms. There is no significant change in the potential of the F atoms due to coordination of C-6-aromatic fluorides, as in the case of aliphatic ones. This results in slight changes in the strengths of the C-H/F and F/F interactions (coupled with parallel interaction at large offsets, PILO), in a noticeable enhancement of stacking interactions, as well as in a significant enhancement of interactions involving the pi-system (F/pi - and C-H/pi interactions). It has also been shown that a decrease in the charge of the metal ions leads to a decrease in the negative potential of the F atom and also that the nature of the metal ion has a significant influence on the value of the potential of the F atoms

    On the supramolecular outcomes of fluorination of cyclohexane-5-spirohydantoin derivatives

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    The quantitative assessment of intermolecular interactions and their cooperative effects has been performed in spirohydantoin-based model compounds, 3-benzoyl-1,3-diazaspiro[4.5]decane-2,4-dione (1) and 3-(4-fluorobenzoyl)-1,3-diazaspiro[4.5]decane-2,4-dione (2), through single crystal X-ray crystallography and quantum chemical studies. In both crystal structures, molecules generate the same hydrogen-bonded centrosymmetric R22(8) synthon. The extended supramolecular architectures depend on the C-HMIDLINE HORIZONTAL ELLIPSISO, C-HMIDLINE HORIZONTAL ELLIPSIS pi, stacking interactions and parallel interactions at large offsets, which lead to molecular sheets and further, with the assistance of the C-HMIDLINE HORIZONTAL ELLIPSISF interaction in the case of 2, to three-dimensional networks. Electrostatic potential maps have indicated that formation of the intermolecular FMIDLINE HORIZONTAL ELLIPSISF interaction in the crystal structure of 2 results in a new region with a larger surface area and a higher negative potential in comparison to the individual fluorine atoms. Establishment of this interaction leads to strengthening of the interaction of one of the fluorine atoms with a third molecule from the environment which does not interact with both of them. When this third molecule interacts with both fluorine atoms simultaneously, the calculations have shown that the effect of strengthening of the individual interactions due to formation of the FMIDLINE HORIZONTAL ELLIPSISF interaction is absent
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