Tailored risk assessment and forecasting in intermittent claudication.

Background: Guidelines recommend cardiovascular risk reduction and supervised exercise therapy as the first line of treatment in intermittent claudication, but implementation challenges and poor patient compliance lead to significant variation in management and therefore outcomes. The development of a precise risk stratification tool is proposed through a machine-learning algorithm that aims to provide personalized outcome predictions for different management strategies.

Methods: Feature selection was performed using the least absolute shrinkage and selection operator method.

Data-Driven Techniques for Low-Cost Sensor Selection and Calibration for the Use Case of Air Quality Monitoring.

With the emergence of Low-Cost Sensor (LCS) devices, measuring real-time data on a large scale has become a feasible alternative approach to more costly devices. Over the years, sensor technologies have evolved which has provided the opportunity to have diversity in LCS selection for the same task. However, this diversity in sensor types adds complexity to appropriate sensor selection for monitoring tasks.

Atmospheric oxidation of HFE-7300 [n-CFCF(OCH)CF(CF)] initiated by OH/Cl oxidants and subsequent degradation of its product radical: a DFT approach.

To understand the atmospheric chemistry of hydrofluoroethers, we have studied the oxidation of a highly fluorinated compound n-CFCF(OCH)CF(CF) (HFE-7300) by OH/Cl oxidants. Here, we have employed M06-2X functional along with a 6-31 + G(d,p) basis set to obtain the optimized structures, various forms of energies, and different modes of frequencies for all species. We have characterized energies of all species on the potential energy surface, and it indicates that H-abstraction from n-CFCF(OCH)CF(CF) by Cl atom is kinetically more dominant than the H-abstraction reaction initiated by OH radical.

Theoretical insight on atmospheric chemistry of HFE-365mcf3: reactions with OH radicals, atmospheric lifetime, and fate of alkoxy radicals (CF3CF2CH(O(•))OCH3/CF3CF2CH2OCH2O(•)).

In the present work, theoretical study on the mechanism and kinetics of the gas-phase reactions of CF3CF2CH2OCH3 (HFE-365mcf3) with the OH radicals have been performed using meta-hybrid modern density functional M06-2X in conjunction with 6-31+G(d,p) basis set. Reaction profiles for OH-initiated hydrogen abstraction are modeled including the formation of pre-reactive and post-reactive complexes at entrance and exit channels. Our calculations reveal that hydrogen abstraction from the -CH2 group is thermodynamically more facile than that from the -CH3 group.

Theoretical investigation on mechanism and kinetics of the Cl-initiated hydrogen abstraction reactions of ethyl trifluoroacetate at 298 K.

Theoretical investigations were carried out on the gas-phase reactions of CF3C(O)OCH2CH3, ethyl trifluoroacetate (ETFA) with Cl atoms by means of modern density functional theory methods. The optimized geometries, frequencies and minimum energy path were obtained with the hybrid density functional model MPWB1K using the 6-31+G(d,p) basis set. The single point energy calculations were refined further using the G2(MP2) method.

Theoretical investigation on the atmospheric fate of CF3C(O)OCH 2O radical: alpha-ester rearrangement vs oxidation at 298 K.

A theoretical study on the mechanism of the thermal decomposition of CF(3)C(O)OCH(2)O radical is presented for the first time. Geometry optimization and frequency calculations were performed at the MPWB1K/6-31 + G(d, p) level of theory and energetic information further refined by calculating the energy of the species using G2(MP2) theory. Three plausible decomposition pathways including α-ester rearrangement, reaction with O(2) and thermal decomposition (C-O bond scission) were considered in detail.

A theoretical investigation on kinetics, mechanism, and thermochemistry of the gas-phase reactions of methyl fluoroacetate with OH radicals and fate of alkoxy radical.

We theoretically investigated OH-initiated hydrogen abstraction reactions of methyl fluoroacetate (MFA) CH2FC(O)OCH3 at the MPWB1K level of theory in conjunction with the 6-31+G(d,p) basis set. Thermodynamic and kinetic data are computed using the comparatively accurate G2(MP2) method. Two most stable conformers of MFA are identified, and the energy difference between them is found to be only 0.

Theoretical studies on kinetics, mechanism and thermochemistry of gas-phase reactions of HFE-449mec-f with OH radicals and Cl atom.

A theoretical study on the mechanism and kinetics of the gas phase reactions of CF3CHFCF2OCH2CF3 (HFE-449mec-f) with the OH radicals and Cl atom have been performed using meta-hybrid modern density functional M06-2X using 6-31+G(d,p) basis set. Two conformers have been identified for CF3CHFCF2OCH2CF3 and the most stable one is considered for detailed study. Reaction profiles for OH-initiated hydrogen abstraction are modeled including the formation of pre-reactive and post-reactive complexes at entrance and exit channels.

Theoretical investigation on gas-phase reaction of CF3CH2OCH3 with OH radicals and fate of alkoxy radicals (CF3CH(O•)OCH3/CF3CH2OCH2O•).

Detailed theoretical investigation has been performed on the mechanism, kinetics and thermochemistry of the gas phase reactions of CF3CH2OCH3 (HFE-263fb2) with OH radicals using ab-initio and DFT methods. Reaction profiles are modeled including the formation of pre-reactive and post-reactive complexes at entrance and exit channels, respectively. Our calculations reveal that hydrogen abstraction from the CH2 group is thermodynamically and kinetically more facile than that from the CH3 group.

Theoretical investigation of the gas-phase reactions of CF2ClC(O)OCH3 with the hydroxyl radical and the chlorine atom at 298 K.

A Theoretical study on the mechanism of the reactions of CF2ClC(O)OCH3 with the OH radical and Cl atom is presented. Geometry optimization and frequency calculations have been performed at the MPWB1K/6-31+G(d,p) level of theory and energetic information is further refined by calculating the energy of the species using G2(MP2) theory. Transition states are searched on the potential energy surface involved during the reaction channels and each of the transition states are characterized by presence of only one imaginary frequency.

Theoretical study on rate constants for the reactions of CF3CH 2NH 2 (TFEA) with the hydroxyl radical at 298 K and atmospheric pressure.

Theoretical investigations are carried out on reaction mechanism of the reactions of CF3CH2NH2 (TFEA) with the OH radical by means of ab initio and DFT methods. The electronic structure information on the potential energy surface for each reaction is obtained at MPWB1K/6-31+G(d,p) level and energetic information is further refined by calculating the energy of the species with a Gaussian-2 method, G2(MP2). The existence of transition states on the corresponding potential energy surface is ascertained by performing intrinsic reaction coordinate (IRC) calculation.

Ab initio studies on the decomposition kinetics of CF3OCF2O radical.

The present study deals with the decomposition of CF(3)OCF(2)O radical formed from a hydrofluoroether, CF(3)OCHF(2) (HFE-125), in the atmosphere. The study is performed using ab initio quantum mechanical methods. Two plausible pathways of decomposition of the titled species have been considered, one involving C-O bond scission and the other occurring via F atom elimination.

Ab initio studies on the reactivity of the CF3OCH 2O radical: thermal decomposition vs. reaction with O2.

Hydrofluoroethers are being considered as potential candidates for third generation refrigerants. The present investigation involves the ab initio quantum mechanical study of the decomposition mechanism of CF(3)OCH(2)O radical formed from a hydrofluoroether, CF(3)OCH(3) (HFE-143a) in the atmosphere. The geometries of the reactant, products and transition states involved in the decomposition pathways are optimized and characterized at the DFT (B3LYP) level of theory using 6-311G(d,p) basis set.