scholarly journals Relative Rate and Product Studies of the Reactions of Atomic Chlorine with Tetrafluoroethylene, 1,2-Dichloro-1,2-difluoroethylene, 1,1-Dichloro-2,2-difluoroethylene, and Hexafluoro-1,3-butadiene in the Presence of Oxygen

2016 ◽  
Vol 120 (37) ◽  
pp. 7311-7319 ◽  
Author(s):  
Thushani N. Herath ◽  
Eric C. Clinch ◽  
Ivan Orozco ◽  
Erin L. Raign ◽  
Paul Marshall
Keyword(s):  
Relative Rate ◽  
Atomic Chlorine

scholarly journals Relative Rate Studies of the Reactions of Atomic Chlorine with Acetone and Cyclic Ketones

2017 ◽  
Vol 50 (1) ◽  
pp. 41-46 ◽  
Author(s):  
Thushani N. Herath ◽  
Ivan Orozco ◽  
Eric C. Clinch ◽  
Paul Marshall
Keyword(s):  
Relative Rate ◽  
Cyclic Ketones ◽  
Atomic Chlorine

scholarly journals Kinetic study of the gas-phase reaction of atomic chlorine with a series of aldehydes

2005 ◽  
Vol 5 (12) ◽  
pp. 3433-3440 ◽  
Author(s):  
D. Rodríguez ◽  
A. Rodríguez ◽  
A. Notario ◽  
A. Aranda ◽  
Y. Díaz-de-Mera ◽  
...  
Keyword(s):  
Relative Rate ◽  
Weighted Average ◽  
Rate Coefficients ◽  
Phase Reaction ◽  
Additional Information ◽  
Relative Rate Constants ◽  
Relative Measurements ◽  
First Time ◽  
Structure Versus ◽  
Atomic Chlorine

Abstract. The reactions of Cl atoms with a series of unsaturated aldehydes have been investigated for the first time using a relative method. In order to obtain additional information for a qualitative structure versus reactivity discussion, we have also determined the rate coefficients for the reactions of atomic chlorine with their respective saturated aldehydes. These relative measurements were performed at room temperature and atmospheric pressure of air and N2, by using ethane, propene and 1-butene as reference compounds. The weighted average relative rate constants obtained, kCl±2σ (in units of cm3 molecule−1 s−1) were: trans-2-pentenal (1.31±0.19)×10−10; trans-2-hexenal (1.92±0.22)×10−10; trans-2-heptenal (2.40±0.29)×10−10; n-pentanal (2.56±0.27)×10−10; n-hexanal (2.88±0.37)×10−10; n-heptanal (3.00±0.34)×10−10. Finally, results and atmospheric implications are discussed and compared with the reactivity with OH and NO3 radicals.

scholarly journals Kinetic study of the gas-phase reaction of atomic chlorine with a series of aldehydes

2005 ◽  
Vol 5 (4) ◽  
pp. 5167-5182 ◽  
Author(s):  
D. Rodríguez ◽  
A. Rodríguez ◽  
A. Notario ◽  
A. Aranda ◽  
Y. Díaz-de-Mera ◽  
...  
Keyword(s):  
Relative Rate ◽  
Weighted Average ◽  
Rate Coefficients ◽  
Phase Reaction ◽  
Additional Information ◽  
Relative Rate Constants ◽  
Relative Measurements ◽  
First Time ◽  
Structure Versus ◽  
Atomic Chlorine

Abstract. The reactions of Cl atoms with a series of unsaturated aldehydes have been investigated for the first time using a relative method. In order to obtain additional information for a qualitative structure versus reactivity discussion, we have also determined, for the first time, the rate coefficients for the reactions of atomic chlorine with their respective saturated aldehydes. These relative measurements were performed at room temperature and atmospheric pressure of air and N2, by using ethane, propene and 1-butene as reference compounds. The weighted average relative rate constants obtained, kCl±2σ (in units of cm3 molecule−1 s−1) were: trans-2-pentenal (1.31±0.19)×10−10; trans-2-hexenal (1.92±0.22)×10−10; trans-2-heptenal (2.40±0.29)×10−10; n-pentanal (2.56±0.27)×10−10; n-hexanal (2.88±0.37)×10−10; n-heptanal (3.00±0.34)×10−10. Finally, results and atmospheric implications are discussed and compared with the reactivity with OH and NO3 radicals.

Relative rate measurements of reactions of unsaturated alcohols with atomic chlorine as a function of temperature

2007 ◽  
Vol 41 (22) ◽  
pp. 4693-4702 ◽  
Author(s):  
Ana Rodríguez ◽  
Diana Rodríguez ◽  
Amparo Soto ◽  
Alberto Notario ◽  
Alfonso Aranda ◽  
...  
Keyword(s):  
Relative Rate ◽  
Unsaturated Alcohols ◽  
Atomic Chlorine

Research Trends in Anticoagulation Therapy over the Last 25 Years

2020 ◽  
Vol 46 (08) ◽  
pp. 919-931
Author(s):  
Mustafa K. Mian ◽  
Subhashaan Sreedharan ◽  
Neeraj S. Limaye ◽  
Chris Hogan ◽  
Jai N. Darvall
Keyword(s):  
Conflicts Of Interest ◽  
Relative Rate ◽  
Vitamin K Antagonists ◽  
Oral Anticoagulants ◽  
Citation Count ◽  
Anticoagulation Therapy ◽  
Journal Title ◽  
Common Source ◽  
Level I ◽  
High Level

AbstractA large volume of literature has become available to practitioners prescribing anticoagulants. The aim of this study was to analyze the bibliometric characteristics of the top 100 most cited articles related to anticoagulation over the past 25 years, with special consideration to impact of direct or “nonvitamin K antagonist” oral anticoagulants (NOACs) compared with vitamin K antagonists. A bibliometric analysis of the 100 most cited journal articles related to anticoagulants published between 1994 and 2019 was performed in April 2019. The top 100 articles by citation count were analyzed to extract bibliometric data related to journal title, impact factor, year of publication, place of publication, anticoagulant studied, indication for anticoagulation, study design, and conflicts of interest. The median (interquartile range) number of citations per article was 806 (621–1,085). The anticoagulant most frequently researched was warfarin (37%). NOAC publications (21%) grew at a relative rate of 3.4 times faster compared with all publications. The indication most commonly researched was venous thromboembolism (26%). Eighty articles constituted level I or II evidence, with randomized controlled trials the most common type of study (74). A financial conflict of interest was declared in 87% of articles with private, for-profit organizations the most common source of funding (26%). In summary, top research related to anticoagulation is highly impactful but may be at risk of sponsorship bias. High-level evidence for NOACs continues to expand across a range of indications with citation metrics likely to soon approach or surpass that of older drugs.

scholarly journals Selection Response in Finite Populations

Genetics ◽  
1996 ◽  
Vol 144 (4) ◽  
pp. 1961-1974 ◽  
Author(s):  
Ming Wei ◽  
Armando Caballero ◽  
William G Hill
Keyword(s):  
Linkage Disequilibrium ◽  
Inbreeding Depression ◽  
Genetic Variance ◽  
Relative Rate ◽  
Selection Response ◽  
Rate Of Change ◽  
Effective Population ◽  
Short Term ◽  
Model Account

Formulae were derived to predict genetic response under various selection schemes assuming an infinitesimal model. Account was taken of genetic drift, gametic (linkage) disequilibrium (Bulmer effect), inbreeding depression, common environmental variance, and both initial segregating variance within families (σAW02) and mutational (σM2) variance. The cumulative response to selection until generation t(CRt) can be approximated asCRt≈R0[t−β(1−σAW∞2σAW02)t24Ne]−Dt2Ne,where Ne is the effective population size, σAW∞2=NeσM2 is the genetic variance within families at the steady state (or one-half the genic variance, which is unaffected by selection), and D is the inbreeding depression per unit of inbreeding. R  0 is the selection response at generation 0 assuming preselection so that the linkage disequilibrium effect has stabilized. β is the derivative of the logarithm of the asymptotic response with respect to the logarithm of the within-family genetic variance, i.e., their relative rate of change. R  0 is the major determinant of the short term selection response, but σM2, Ne and β are also important for the long term. A selection method of high accuracy using family information gives a small Ne and will lead to a larger response in the short term and a smaller response in the long term, utilizing mutation less efficiently.

NITROGEN TRANSFORMATIONS NEAR UREA IN SOIL WITH DIFFERENT WATER POTENTIALS

1988 ◽  
Vol 68 (3) ◽  
pp. 569-576 ◽  
Author(s):  
YADVINDER SINGH ◽  
E. G. BEAUCHAMP
Keyword(s):  
Water Potential ◽  
Soil Water ◽  
Incubation Period ◽  
Relative Rate ◽  
Soil Water Potential ◽  
Nitrification Inhibitor ◽  
Silt Loam ◽  
Nitrogen Transformations ◽  
Water Potentials ◽  
Initial Soil

Two laboratory incubation experiments were conducted to determine the effect of initial soil water potential on the transformation of urea in large granules to nitrite and nitrate. In the first experiment two soils varying in initial soil water potentials (− 70 and − 140 kPa) were incubated with 2 g urea granules with and without a nitrification inhibitor (dicyandiamide) at 15 °C for 35 d. Only a trace of [Formula: see text] accumulated in a Brookston clay (pH 6.0) during the transformation of urea in 2 g granules. Accumulation of [Formula: see text] was also small (4–6 μg N g−1) in Conestogo silt loam (pH 7.6). Incorporation of dicyandiamide (DCD) into the urea granule at 50 g kg−1 urea significantly reduced the accumulation of [Formula: see text] in this soil. The relative rate of nitrification in the absence of DCD at −140 kPa water potential was 63.5% of that at −70 kPa (average of two soils). DCD reduced the nitrification of urea in 2 g granules by 85% during the 35-d period. In the second experiment a uniform layer of 2 g urea was placed in the center of 20-cm-long cores of Conestogo silt loam with three initial water potentials (−35, −60 and −120 kPa) and the soil was incubated at 15 °C for 45 d. The rate of urea hydrolysis was lowest at −120 kPa and greatest at −35 kPa. Soil pH in the vicinity of the urea layer increased from 7.6 to 9.1 and [Formula: see text] concentration was greater than 3000 μg g−1 soil. There were no significant differences in pH or [Formula: see text] concentration with the three soil water potential treatments at the 10th day of the incubation period. But, in the latter part of the incubation period, pH and [Formula: see text] concentration decreased with increasing soil water potential due to a higher rate of nitrification. Diffusion of various N species including [Formula: see text] was probably greater with the highest water potential treatment. Only small quantities of [Formula: see text] accumulated during nitrification of urea – N. Nitrification of urea increased with increasing water potential. After 35 d of incubation, 19.3, 15.4 and 8.9% of the applied urea had apparently nitrified at −35, −60 and −120 kPa, respectively. Nitrifier activity was completely inhibited in the 0- to 2-cm zone near the urea layer for 35 days. Nitrifier activity increased from an initial level of 8.5 to 73 μg [Formula: see text] in the 3- to 7-cm zone over the 35-d period. Nitrifier activity also increased with increasing soil water potential. Key words: Urea transformation, nitrification, water potential, large granules, nitrifier activity, [Formula: see text] production

scholarly journals Association between home insulation and hospital admission rates: retrospective cohort study using linked data from a national intervention programme

BMJ ◽  
2020 ◽  
pp. m4571 ◽  
Author(s):  
Caroline Fyfe ◽  
Lucy Telfar ◽  
Barnard ◽  
Philippa Howden-Chapman ◽  
Jeroen Douwes
Keyword(s):  
Cohort Study ◽  
Heart Disease ◽  
Confidence Interval ◽  
Hospital Admission ◽  
Retrospective Cohort ◽  
Rate Ratio ◽  
Hospital Admissions ◽  
Relative Rate ◽  
Intervention Programme ◽  
Admission Rates

Abstract Objectives To investigate whether retrofitting insulation into homes can reduce cold associated hospital admission rates among residents and to identify whether the effect varies between different groups within the population and by type of insulation. Design A quasi-experimental retrospective cohort study using linked datasets to evaluate a national intervention programme. Participants 994 317 residents of 204 405 houses who received an insulation subsidy through the Energy Efficiency and Conservation Authority Warm-up New Zealand: Heat Smart retrofit programme between July 2009 and June 2014. Main outcome measure A difference-in-difference approach was used to compare the change in hospital admissions of the study population post-insulation with the change in hospital admissions of the control population that did not receive the intervention over the same two timeframes. Relative rate ratios were used to compare the two groups. Results 234 873 hospital admissions occurred during the study period. Hospital admission rates after the intervention increased in the intervention and control groups for all population categories and conditions with the exception of acute hospital admissions among Pacific Peoples (rate ratio 0.94, 95% confidence interval 0.90 to 0.98), asthma (0.92, 0.86 to 0.99), cardiovascular disease (0.90, 0.88 to 0.93), and ischaemic heart disease for adults older than 65 years (0.79, 0.74 to 0.84). Post-intervention increases were, however, significantly lower (11%) in the intervention group compared with the control group (relative rate ratio 0.89, 95% confidence interval 0.88 to 0.90), representing 9.26 (95% confidence interval 9.05 to 9.47) fewer hospital admissions per 1000 in the intervention population. Effects were more pronounced for respiratory disease (0.85, 0.81 to 0.90), asthma in all age groups (0.80, 0.70 to 0.90), and ischaemic heart disease in those older than 65 years (0.75, 0.66 to 0.83). Conclusion This study showed that a national home insulation intervention was associated with reduced hospital admissions, supporting previous research, which found an improvement in self-reported health.

scholarly journals Analysis of substitution rates showed that TLR5 is evolving at different rates among mammalian groups

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Ana Pinheiro ◽  
Ana Águeda-Pinto ◽  
José Melo-Ferreira ◽  
Fabiana Neves ◽  
Joana Abrantes ◽  
...  
Keyword(s):  
Substitution Rate ◽  
Relative Rate ◽  
Purifying Selection ◽  
Genetic Distances ◽  
Major Protein ◽  
Substitution Rates ◽  
Evolutionary Pattern ◽  
Branch Model ◽  
Rate Test ◽  
Species Specific

Abstract Background Toll-like receptors (TLRs) are the most widely studied innate immunity receptors responsible for recognition of invading pathogens. Among the TLR family, TLR5 is the only that senses and recognizes flagellin, the major protein of bacterial flagella. TLR5 has been reported to be under overall purifying selection in mammals, with a small proportion of codons under positive selection. However, the variation of substitution rates among major mammalian groups has been neglected. Here, we studied the evolution of TLR5 in mammals, comparing the substitution rates among groups. Results In this study we analysed the TLR5 substitution rates in Euungulata, Carnivora, Chiroptera, Primata, Rodentia and Lagomorpha, groups. For that, Tajima’s relative rate test, Bayesian inference of evolutionary rates and genetic distances were estimated with CODEML’s branch model and RELAX. The combined results showed that in the Lagomorpha, Rodentia, Carnivora and Chiroptera lineages TLR5 is evolving at a higher substitution rate. The RELAX analysis further suggested a significant relaxation of selective pressures for the Lagomorpha (K = 0.22, p < 0.01), Rodentia (K = 0.58, p < 0.01) and Chiroptera (K = 0.65, p < 0.01) lineages and for the Carnivora ancestral branches (K = 0.13, p < 0.01). Conclusions Our results show that the TLR5 substitution rate is not uniform among mammals. In fact, among the different mammal groups studied, the Lagomorpha, Rodentia, Carnivora and Chiroptera are evolving faster. This evolutionary pattern could be explained by 1) the acquisition of new functions of TLR5 in the groups with higher substitution rate, i.e. TLR5 neofunctionalization, 2) by the beginning of a TLR5 pseudogenization in these groups due to some redundancy between the TLRs genes, or 3) an arms race between TLR5 and species-specific parasites.

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