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1.
PLoS One ; 18(4): e0283901, 2023.
Article in English | MEDLINE | ID: mdl-37018293

ABSTRACT

Preterm birth has been related to inequalities in maternal educational level, but the causal mechanism is not entirely known. Some factors associated with preterm birth and low educational level such as chronic medical conditions, pregnancy complications and related-health behaviours could have a mediation role in the pathway. This study aimed to evaluate the association between maternal educational level and preterm birth, analysing the mediation role of these factors. We performed a retrospective cohort study based on hospital electronic records of 10467 deliveries that took place in the Hospital Clínic of Barcelona between 2011 and 2017. Poisson regression was used to obtain crude and adjusted relative risk of preterm birth in women with different educational level and the percentage of change in relative risk was calculated when mediation variables were included in the model. Women with a lower educational level had a higher risk of preterm birth (RR 1.57, 95% CI 1.21, 2.03). The loss of association after the inclusion of body mass index in the model suggests an important mediation role of maternal overweight. Other variables such as smoking, drug use, preeclampsia and genitourinary infections also appear to play a role in the observed inequality between women with different levels of education. Efforts to promote health literacy and to improve preventive interventions, before and during pregnancy, could decrease preterm birth rates and perinatal health inequalities.


Subject(s)
Premature Birth , Pregnancy , Humans , Infant, Newborn , Female , Premature Birth/etiology , Cohort Studies , Retrospective Studies , Health Promotion , Educational Status , Hospitals
2.
Photochem Photobiol ; 97(6): 1431-1444, 2021 11.
Article in English | MEDLINE | ID: mdl-34115882

ABSTRACT

In this article, four novel fulleropyrrolidines derivatives were synthesized to study how the effect of polarity and positive charge distribution can influence the efficacy of photodynamic inactivation treatments to kill bacteria. The design of the photosensitizers was based on DFT calculations that allowed us to estimate the dipolar moment of the molecules. Neutral compounds bearing N-methyl bis-acetoxy-ethyl (1) and bis-hydroxyethyl (2) amine were the starting material to obtain the dicationic analogs N,N-dimethyl bis-methoxyethyl (3), and bis-acetoxy-ethyl) (4) methylammonio. As expected from fullerene C60 derivatives, compounds 1-4 absorb in the UV region, with a peak at 430 nm, a broader range of absorption up to 710 nm, and exhibit weak fluorescence emission in toluene and reverse micelles. In the biomimetic AOT micellar system, the highest singlet oxygen photosensitization was found for compounds 1, followed by 3, 2, and 4. Whereas 4 was the most effective reducing nitro blue tetrazolium in the presence of ß-NADH. The influence of type I and type II mechanism on the photodynamic activity of compounds 3 and 4 was further examined in the presence of L-tryptophan and two reactive oxygen species scavengers. In vitro experiments indicated that the compounds with the highest dipolar moments, 3 (37.19 D) and 4 (38.46 D), inactivated methicillin-resistant Staphylococcus aureus and Escherichia coli bacteria using an energy dose <2.4 J cm-2 . No inactivation was observed for the neutral analogs with the lowest dipolar moments. These findings help to optimize sensitizer structures to improve photodynamic inactivation.


Subject(s)
Fullerenes , Methicillin-Resistant Staphylococcus aureus , Escherichia coli , Fullerenes/chemistry , Fullerenes/pharmacology , Micelles , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Singlet Oxygen/pharmacology
3.
Int J Mol Sci ; 22(5)2021 Feb 26.
Article in English | MEDLINE | ID: mdl-33652675

ABSTRACT

A priority of modern agriculture is to use novel and environmentally friendly plant-growth promoter compounds to increase crop yields and avoid the indiscriminate use of synthetic fertilizers. Brassinosteroids are directly involved in the growth and development of plants and are considered attractive candidates to solve this problem. Obtaining these metabolites from their natural sources is expensive and cumbersome since they occur in extremely low concentrations in plants. For this reason, much effort has been dedicated in the last decades to synthesize brassinosteroids analogs. In this manuscript, we present the synthesis and characterization of seven steroidal carbamates starting from stigmasterol, ß-sitosterol, diosgenin and several oxygenated derivatives of it. The synthesis route for functionalization of diosgenin included epoxidation and epoxy opening reactions, reduction of carbonyl groups, selective oxidation of hydroxyl groups, among others. All the obtained compounds were characterized by 1H and 13C NMR, HRMS, and their melting points are also reported. Rice lamina inclination test performed at different concentrations established that all reported steroidal carbamates show plant-growth-promoting activity. A molecular docking study evaluated the affinity of the synthesized compounds towards the BRI1-BAK1 receptor from Arabidopsis thaliana and three of the docked compounds displayed a binding energy lower than brassinolide.


Subject(s)
Arabidopsis/growth & development , Carbamates , Molecular Docking Simulation , Oryza/growth & development , Plant Growth Regulators , Brassinosteroids/chemistry , Carbamates/chemical synthesis , Carbamates/chemistry , Carbamates/pharmacology , Plant Growth Regulators/chemical synthesis , Plant Growth Regulators/chemistry , Plant Growth Regulators/pharmacology , Steroids, Heterocyclic/chemistry
4.
PLoS One ; 8(9): e72970, 2013.
Article in English | MEDLINE | ID: mdl-24086267

ABSTRACT

This paper introduces a novel algorithm to compute equivalent latitude by applying regions of interest (ROI). The technique is illustrated using code written in Interactive Data Language (IDL). The ROI method is compared with the "piecewise-constant" method, the approach commonly used in atmospheric sciences, using global fields of atmospheric potential vorticity. The ROI method is considerably more accurate and computationally faster than the piecewise-constant method, and it also works well with irregular grids. Both the ROI and piecewise-constant IDL codes for equivalent latitude are included as a useful reference for the research community.


Subject(s)
Altitude , Geography , Investments
5.
PLoS One ; 8(2): e56909, 2013.
Article in English | MEDLINE | ID: mdl-23451108

ABSTRACT

In this study the depth of the atmospheric boundary layer (ABL) over the Tibetan Plateau was measured during a regional radiosonde observation campaign in 2008 and found to be deeper than indicated by previously measurements. Results indicate that during fair weather conditions on winter days, the top of the mixed layers can be up to 5 km above the ground (9.4 km above sea level). Measurements also show that the depth of the ABL is quite distinct for three different periods (winter, monsoon-onset, and monsoon seasons). Turbulence at the top of a deep mixing layer can rise up to the upper troposphere. As a consequence, as confirmed by trajectory analysis, interaction occurs between deep ABLs and the low tropopause during winter over the Tibetan Plateau.


Subject(s)
Atmosphere , Tibet
6.
PLoS One ; 7(6): e39281, 2012.
Article in English | MEDLINE | ID: mdl-22768069

ABSTRACT

We herein describe the recovery of a series of data on temperature, humidity, precipitation, evaporation, wind, and local weather conditions from documentary sources obtained from the Jesuit observatory of A Guarda (Galicia, Spain) for the period 1881-1896. The data were digitized and made available in accessible electronic formats. Comparisons were made with present-day meteorological data obtained from two nearby stations. We further believe that the discovery of some new complementary documentary sources made during the present research could be a basis for future data recovery efforts. Among these new results, early ozone data from the period are of outstanding importance to meteorologists.


Subject(s)
Meteorological Concepts , Statistics as Topic , Cyclonic Storms , Pressure , Rain , Records , Research Report , Spain , Temperature , Tropical Climate
7.
ScientificWorldJournal ; 2012: 191028, 2012.
Article in English | MEDLINE | ID: mdl-22685385

ABSTRACT

Multiple tropopauses are structures that regularly recur in the midlatitudes. Recent studies have relied on the notion of the excursion of tropical air from the upper troposphere into higher latitudes, thereby overlaying the tropopause of the midlatitudes. We herein analyse the origin and characteristics of the air at the Boulder radiosonde station, between the first and second tropopauses combining an analysis of radiosonde data with a Lagrangian approach based on the FlexPart model and ERA-40 analysis data. Our results show that the air between both tropopauses has its origin in midlatitudes.


Subject(s)
Air/analysis , Atmosphere/analysis , Meteorological Concepts , Models, Statistical , Computer Simulation
8.
Ann N Y Acad Sci ; 1146: 235-55, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19076418

ABSTRACT

Regions of the occurrence of different phenomena related to the development of baroclinic disturbances are reviewed for the Northern Hemisphere extratropics, using National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis data. The occurrence of height lows appears to be related to the orography near the earth's surface and with surface- and upper-air cyclogenesis in the upper troposphere. Over the cyclone tracks, the surface maxima appear to be trapped by land masses, whereas over the Mediterranean Sea they are located on the lee side of mountain ranges. The forcing terms of the geopotential tendency and omega equations mark the genesis (and, by the vorticity advection terms, the path) of the extratropical cyclones on the storm track. They occur mostly over the western coast of the oceans, beginning and having maxima on the lee side of the Rocky Mountains and the Tibetan Plateau. Their associated fronts form from the cold air coming from the continents and converging with the warm air over the Gulf and Kuroshio currents. Evident trends are found only for the Atlantic cyclone track (positive) and the Pacific cyclone track (negative) until the last decade when the tendency reverses. Over the southern Pacific, the number of fronts is lower during 1978-1997, coinciding with a period of strong El Niño Southern Oscillation episodes. This information is important for validating numerical models in order to predict changes associated with climate change and to study the behavior of extratropical cyclones and fronts.


Subject(s)
Atmospheric Pressure , Cyclonic Storms , Tropical Climate , Mediterranean Sea
9.
Interciencia ; 31(12): 841-843, dic. 2006.
Article in Spanish | LILACS | ID: lil-453630

Subject(s)
Science , Women , Mexico
10.
Naturwissenschaften ; 93(12): 603-9, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17047909

ABSTRACT

Previous studies have identified the tropopause height (TH) as a promising fingerprint of climatic change. In the present paper, we report variations in TH for the Eurasian region over the period 1973-1998 and analyse the influence of the Northern Annular Mode (NAM) on these variations. As previous studies indicate that the greatest increases in TH occur in the extratropics, we focused our attention on this area. We applied a set of homogenization procedures to radiosonde data and considered three different scenarios that take into account change points and the main volcanic eruptions over the study period. Our results demonstrate that the number of stations with positive TH trends is very sensitive to the quality of data and the methods used to remove inhomogeneities. Consequently, when change points were included in the analysis, the number of stations with positive trends decreased markedly. Furthermore, stratospheric NAM appears to control TH in stations located at latitudes higher than 55 degrees N.


Subject(s)
Climate , Meteorological Concepts , Asia , Atmosphere , Body Height , Europe , Humans , Pressure , Temperature
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