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1.
Atmos Environ (1994) ; 244: 117834, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32895604

RESUMEN

Global aviation operations contribute to anthropogenic climate change via a complex set of processes that lead to a net surface warming. Of importance are aviation emissions of carbon dioxide (CO2), nitrogen oxides (NOx), water vapor, soot and sulfate aerosols, and increased cloudiness due to contrail formation. Aviation grew strongly over the past decades (1960-2018) in terms of activity, with revenue passenger kilometers increasing from 109 to 8269 billion km yr-1, and in terms of climate change impacts, with CO2 emissions increasing by a factor of 6.8 to 1034 Tg CO2 yr-1. Over the period 2013-2018, the growth rates in both terms show a marked increase. Here, we present a new comprehensive and quantitative approach for evaluating aviation climate forcing terms. Both radiative forcing (RF) and effective radiative forcing (ERF) terms and their sums are calculated for the years 2000-2018. Contrail cirrus, consisting of linear contrails and the cirrus cloudiness arising from them, yields the largest positive net (warming) ERF term followed by CO2 and NOx emissions. The formation and emission of sulfate aerosol yields a negative (cooling) term. The mean contrail cirrus ERF/RF ratio of 0.42 indicates that contrail cirrus is less effective in surface warming than other terms. For 2018 the net aviation ERF is +100.9 milliwatts (mW) m-2 (5-95% likelihood range of (55, 145)) with major contributions from contrail cirrus (57.4 mW m-2), CO2 (34.3 mW m-2), and NOx (17.5 mW m-2). Non-CO2 terms sum to yield a net positive (warming) ERF that accounts for more than half (66%) of the aviation net ERF in 2018. Using normalization to aviation fuel use, the contribution of global aviation in 2011 was calculated to be 3.5 (4.0, 3.4) % of the net anthropogenic ERF of 2290 (1130, 3330) mW m-2. Uncertainty distributions (5%, 95%) show that non-CO2 forcing terms contribute about 8 times more than CO2 to the uncertainty in the aviation net ERF in 2018. The best estimates of the ERFs from aviation aerosol-cloud interactions for soot and sulfate remain undetermined. CO2-warming-equivalent emissions based on global warming potentials (GWP* method) indicate that aviation emissions are currently warming the climate at approximately three times the rate of that associated with aviation CO2 emissions alone. CO2 and NOx aviation emissions and cloud effects remain a continued focus of anthropogenic climate change research and policy discussions.

2.
Curr Med Res Opin ; 27(1): 99-105, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21091392

RESUMEN

INTRODUCTION: High efficacy of statin therapy in primary and secondary prevention of coronary heart disease (CHD) has been confirmed in numerous clinical trials. However, studies' results do not reflect patient benefits in everyday clinical practice. Observed discrepancies are the result of patients' failure to comply with medical recommendations regarding both non-pharmacological and pharmacological treatment. Non-compliance can lead to serious health and economic consequences. OBJECTIVES: The purpose of the presented study was the retrospective analysis of compliance in patients treated with statins on the basis of Polish reimbursement data from the National Health Fund (NFZ). METHODS: Medication Possession Ratio (MPR) was used for the compliance assessment; proportion of patients achieving the minimum level of compliance which ensure a satisfactory clinical response was also evaluated. Number of days to discontinuation was calculated in order to estimate patient persistence representing the time over which a patient continues to fill a prescription. RESULTS: The results of the analysis indicate that only 12% of the population of patients treated with statins demonstrates proper level of both compliance and persistence. Statistically significant differences were found among different patient groups; however, in all the groups, compliance was lower than the minimal level required for clinical benefits. CONCLUSIONS: The study revealed poor compliance among patients receiving statin prescriptions for hyperlipidaemia treatment. We presume that the most important factor for non-adherence can be lack of proper patient education, thus all patients on statin treatment should receive sufficient attention, supervision and better information.


Asunto(s)
Enfermedad Coronaria/prevención & control , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Cooperación del Paciente , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Enfermedad Coronaria/epidemiología , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Cooperación del Paciente/estadística & datos numéricos , Polonia/epidemiología , Sistema de Registros , Estudios Retrospectivos , Adulto Joven
3.
Acta Crystallogr B ; 55(Pt 5): 698-711, 1999 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-10927409

RESUMEN

The ionic model is shown to be applicable to all compounds in which the atoms carry a net charge and their electron density is spherically symmetric regardless of the covalent character of the bonding. By examining the electric field generated by an array of point charges placed at the positions of the ions in over 40 inorganic compounds, we show that the Coulomb field naturally partitions itself into localized regions (bonds) which are characterized by the electric flux that links neighbouring ions of opposite charge. This flux is identified with the bond valence, and Gauss' law with the valence-sum rule, providing a secure theoretical foundation for the bond-valence model. The localization of the Coulomb field provides an unambiguous definition of coordination number and our calculations show that, in addition to the expected primary coordination sphere, there are a number of weak bonds between cations and the anions in the second coordination sphere. Long-range Coulomb interactions are transmitted through the crystal by the application of Gauss' law at each of the intermediate atoms. Bond fluxes have also been calculated for compounds containing ions with non-spherical electron densities (e.g. cations with stereoactive lone electron pairs). In these cases the point-charge model continues to describe the distant field, but multipoles must be added to the point charges to give the correct local field.

4.
Acta Pol Pharm ; 52(2): 129-32, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8960243

RESUMEN

The new class of compounds characterized by anxiolytic or antidepressive properties, including a number of N-(1-aryl-4-piperazinylbutyl) derivatives of the two isomers: 7-isopropyl-6-methyl- and 1-isopropyl-4-methylbicyclo [2.2.2]oct-5-ene-2,3-dicarboxyimide was synthesized. Two compounds were selected for further pharmacological study.


Asunto(s)
Ansiolíticos/síntesis química , Antidepresivos/síntesis química , Animales , Ansiolíticos/farmacología , Antidepresivos/farmacología
11.
S Afr Med J ; 41(13): 338-40, 1967 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-6024383
12.
S Afr Med J ; 41(11): 274-6, 1967 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-6023250
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