Background: Guidelines recommend considering percutaneous left atrial appendage occlusion (LAAO) in patients with atrial fibrillation (AF) at moderate to high stroke risk and contraindications to long-term anticoagulation. Discontinuation of anticoagulation in this patient population, without an alternative treatment option, may place patients at unnecessary risk. This study aimed to assess the prevalence of discussions around LAAO as a treatment option following major bleeding adverse events in patients on oral anticoagulation for AF and to identify the proportion of patients stopping anticoagulation without evidence of LAAO discussions.
View Article and Find Full Text PDFThe rate coefficients for the reactions for XO (XO, X = Cl, Br, I) + isoprene were calculated using the RRKM and ILT approach in master equation simulation (MESMER) in the temperature range of 200-400 K at 1 atm pressure. The thermochemical and energy parameters for ClO + isoprene were calculated using the CCSD(T)/aug-cc-pVDZ//B3LYP/6-31g(2df,p) theory. In the case of the BrO and IO radical reaction, all thermochemical parameters were calculated using CCSD(T)/AVDZ//M06-2X/AVDZ (AVDZ = aug-cc-pVDZ for C, H, and O atoms and aug-cc-pVDZ-pp for the Br atom with effective core potential (ECP) approximation) and CCSD(T)/AVDZ_ecp//M06-2X/AVDZ_ecp (AVDZ_ecp = aug-cc-pVDZ for C, H, and O atoms and Def2SVP for I atom with ECP), respectively.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
December 2024
Temperature-dependent kinetics of Criegee intermediate (CHOO) with 2-pentanone were performed at 258-318 K and 50 Torr using pulsed laser photolysis-cavity ring-down spectroscopy (PLP-CRDS) technique. The measured room temperature rate coefficient was (3.84 ± 0.
View Article and Find Full Text PDFTo maintain its development, the growing fetus is directly dependent on the placenta, an organ that acts as both a modulator and mediator. As an essential component of pregnancy that is derived from both maternal and fetal tissues, the placenta facilitates the passage of all oxygen and nutrients from the expecting parent to their fetuses. Further, the placenta conveys multiple impacts of the maternal environment to the growing fetus.
View Article and Find Full Text PDFTemperature-dependent rate coefficients for the reactions of 2-methyl tetrahydrofuran (MTHF) with Cl atoms in the temperature range of 268-343 K at atmospheric pressure were measured using the relative-rate method. Ethylene and propane were used as reference compounds. Quantitative analysis of the post-photolysis reaction mixture was conducted using a gas chromatograph paired with a flame ionization detector (GC-FID).
View Article and Find Full Text PDFPyrolysis of a branched alcohol, 2-methyl-2-butanol (2M2BOH), was carried out behind the reflected shock wave in the temperature range of 1011-1303 K and under pressures varying from 9.3 to 14.6 atm.
View Article and Find Full Text PDFTemperature-dependent kinetics of OH radical and Cl atom-initiated reaction of an important halogenated alkene, 2,3-Dichloropropene (23DCP), were investigated using absolute and relative methods over 278-363 K. Pulsed laser photolysis - laser induced fluorescence technique and relative rate method using gas chromatography with flame ionization detector were employed for studying the kinetics of 23DCP with OH radical and Cl atom, respectively. The obtained Arrhenius expressions were k(expt)=(4.
View Article and Find Full Text PDFThe reactions of the simplest Criegee intermediate (CHOO) with -butyraldehyde (BD) and isobutyraldehyde (iBD) were studied at 253-318 K and (50 ± 2) torr, using Cavity Ring-down spectroscopy (CRDS). The rate coefficients obtained at room temperature were (2.63 ± 0.
View Article and Find Full Text PDFThe relative rate method was employed to investigate the kinetics of the Cl-initiated reactions of 1-chlorobutane (1-CB) and 2-chlorobutane (2-CB) over 263-363 K, and the measured rate coefficients at room temperature are (1.04 ± 0.24) × 10 and (5.
View Article and Find Full Text PDFIn the present work, the temperature-dependent kinetics for the reaction of -butyl chloride (TBC) with OH radicals and Cl atoms were determined experimentally between 268 and 363 K, and theoretically between 200 and 400 K. Pulsed laser photolysis-laser induced fluorescence (PLP-LIF) and relative rate (RR) methods were used to obtain the rate coefficients for the reaction of TBC with OH radicals and Cl atoms, respectively. The Arrhenius equations and were obtained for both reactions based on the experimentally measured rate coefficients.
View Article and Find Full Text PDFGrasping an object is one of the several tasks performed by human hands. Object stabilization while grasping is a fundamental aspect to consider for the safety of grasped objects. Fingertip forces re-distribute to establish equilibrium when systematic variations are introduced to objects held in hand.
View Article and Find Full Text PDFThe temperature-dependent kinetics was investigated for the reaction of the simplest Criegee intermediate (CHOO) with Methyl-ethyl ketone (CHCOCH, MEK). A direct method was employed to measure the rate of change of the concentration of CHOO using a highly sensitive Pulsed Laser Photolysis-Cavity Ring-down Spectroscopy (PLP-CRDS) technique. The temperature dependent rate coefficient obtained for the CHOO + MEK reaction was k(T = 258-318 K) = (1.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
February 2023
Kinetics of the reaction of IO radicals with methanol (MeOH) and ethanol (EtOH) were experimentally studied in the gas phase using pulsed laser photolysis-cavity ring-down spectroscopy (PLP-CRDS). IO radicals were produced in situ at the reaction zone by photolysing a mixture of precursors (CHI + O + N) at 248 nm and thereby electronically excited at 445.04 nm.
View Article and Find Full Text PDFFormyl (HCO) radicals were generated in situ in the gas phase via the photolysis of glyoxal in N at 248 nm using the pulsed laser photolysis-cavity ring-down spectrometry technique, and the absorption cross-section of the radical was measured to be σ = (5.3 ± 0.9) × 10 cm molecule at 298 K and 615.
View Article and Find Full Text PDFThis article presents the fingertip forces and moments data of the individual fingers and thumb when the thumb was placed on an unsteady platform, when the mass of the handle was systematically increased and when the thumb normal force was restricted while grasping a handle. Further, this article also includes a dataset while the thumb makes vertical movements such as extension (or upward motion) and flexion movement (or downward motion) during the static holding of a handle. An instrumented five-finger prehension handle was designed with a vertical railing on the thumb side.
View Article and Find Full Text PDFSuccessful object interaction during daily living involves maintaining the grasped object in static equilibrium by properly arranging the fingertip contact forces. According to the mechanical advantage hypothesis of grasping, during torque production tasks, fingers with longer moment arms would produce greater normal force than those with shorter moment arms. Previous studies have probed this hypothesis by investigating the force contributions of individual fingers through systematic variations (or perturbations) of the properties of the grasped handle.
View Article and Find Full Text PDFThe gas-phase kinetics of the reactions of IO radicals with ethyl formate (EF) and ethyl acetate (EA) were investigated experimentally using cavity ring-down spectroscopy (CRDS). IO radicals were generated in the CRD reaction zone by photolyzing a mixture of (CHI + O + N) at 248 nm and thereby probed at 445.04 nm.
View Article and Find Full Text PDFThe reactivity of 2-ethoxy ethanol with OH radicals was experimentally measured in the temperature range of 278-363 K using the pulsed laser photolysis-laser-induced fluorescence (PLP-LIF) technique. The rate coefficient at room temperature was measured to be (1.14 ± 0.
View Article and Find Full Text PDFThe thermal unimolecular decomposition of 2-methyltetrahydrofuran (2-MTHF) was studied behind reflected shock waves in a single-pulse shock tube over the temperature range of 1179-1361 K and pressure range of 9-17 atm. Methane, ethylene, ethane, 1,3-butadiene, propylene, acetaldehyde, and acetylene were identified as products in the decomposition of 2-MTHF. A reaction scheme was proposed to explain the mechanism for the observed products.
View Article and Find Full Text PDFThe gas-phase kinetics for the reactions of OH radicals and Cl atoms with 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol (HF2M2P) were measured at temperatures between 268 and 363 K using the relative rate experimental technique. Methane and acetonitrile were used as reference compounds to measure the rate coefficients of the title reactions. For the reactions of HF2M2P with OH radicals and Cl atoms, the rate coefficients were measured to be (7.
View Article and Find Full Text PDFKinetics for the reactions of methyl-2-methyl butanoate (M2MB) and methyl-3-methyl butanoate (M3MB) with OH radicals were carried out using the relative rate technique with gas chromatography-flame ionization detection (RR-GC-FID) in the temperature range of 268-363 K and at 760 Torr of N. The temperature-dependent rate coefficients ( in cm molecule s) for the reaction of M2MB with OH radicals from 268 to 363 K were measured to be = (4.62 ± 1.
View Article and Find Full Text PDFBackground: The human hand plays a crucial role in accomplishing activities of daily living. The contribution of each finger in the human hand is remarkably unique in establishing object stabilization. According to the mechanical advantage hypothesis, the little finger tends to exert a greater normal force than the ring finger during a supination moment production task to stabilize the object.
View Article and Find Full Text PDFCavity ring-down spectroscopy (CRDS) was employed to investigate the kinetics of the reaction between phenyl radicals (CH) and ethyl acetate (EtOAc) in the gas phase. Nitrosobenzene (CHNO) was used as the radical precursor to generate CH at 248 nm, and the generated radicals were subsequently probed at 504.8 nm.
View Article and Find Full Text PDFIn this work, the origin of the singlet and triplet exciton-induced degradation of host materials with C(sp2)-N(sp3) bonds around nitrogen (carbazoles, acridines, etc.), connecting donor and acceptor units, was unravelled using DFT and CASSCF methods. The results reveal that molecules (employed in OLEDs) with basic units containing C(sp2)-N(sp3) bonds (nitrogen connected to carbon in a triangular fashion) have a natural tendency to fragment at the C-N bond through an S1/S0 conical intersection (CI).
View Article and Find Full Text PDFThe relative rate (RR) technique was used for the measurement of OH-initiated photooxidation reactions of ethyl 2-methylpropionate (E2MP) and ethyl 2,2-dimethylpropionate (E22DMP) in the temperature range of 268-363 K at 760 Torr. In addition to this, the thermodynamic and kinetic parameters for the title reactions were theoretically investigated using CCSD(T)/cc-pVTZ//M06-2X/6-311++G(2d,2p) level of theory in the temperature range of 200-400 K using canonical variational transition state theory (CVT) in combination with small curvature tunneling (SCT) method. The rate coefficients at (298 ± 2) K were measured to be = (2.
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