740 research outputs found
Complementary medicine products used in pregnancy and lactation and an examination of the information sources accessed pertaining to maternal health literacy: A systematic review of qualitative studies
© 2018 The Author(s). Background: The prevalence of complementary medicine use in pregnancy and lactation has been increasingly noted internationally. This systematic review aimed to determine the complementary medicine products (CMPs) used in pregnancy and/or lactation for the benefit of the mother, the pregnancy, child and/or the breastfeeding process. Additionally, it aimed to explore the resources women used, and to examine the role of maternal health literacy in this process. Methods: Seven databases were comprehensively searched to identify studies published in peer-reviewed journals (1995-2017). Relevant data were extracted and thematic analysis undertaken to identify key themes related to the review objectives. Results: A total of 4574 articles were identified; 28 qualitative studies met the inclusion criteria. Quantitative studies were removed for a separate, concurrent review. Herbal medicines were the main CMPs identified (n=21 papers) in the qualitative studies, with a smaller number examining vitamin and mineral supplements together with herbal medicines (n=3), and micronutrient supplements (n=3). Shared cultural knowledge and traditions, followed by women elders and health care professionals were the information sources most accessed by women when choosing to use CMPs. Women used CMPs for perceived physical, mental-emotional, spiritual and cultural benefits for their pregnancies, their own health, the health of their unborn or breastfeeding babies, and/or the breastfeeding process. Two over-arching motives were identified: 1) to protect themselves or their babies from adverse events; 2) to facilitate the normal physiological processes of pregnancy, birth and lactation. Decisions to use CMPs were made within the context of their own cultures, reflected in the locus of control regarding decision-making in pregnancy and lactation, and in the health literacy environment. Medical pluralism was very common and women navigated through and between different health care services and systems throughout their pregnancies and breastfeeding journeys. Conclusions: Pregnant and breastfeeding women use herbal medicines and micronutrient supplements for a variety of perceived benefits to their babies' and their own holistic health. Women access a range of CMP-related information sources with shared cultural knowledge and women elders the most frequently accessed sources, followed by HCPs. Culture influences maternal health literacy and thus women's health care choices including CMP use
Cloud chemistry at the Puy de DĂŽme: variability and relationships with environmental factors
The chemical composition of cloud water was investigated during the winter-spring months of 2001 and 2002 at the Puy de Dôme station (1465 m above sea level, 45°46′22′′ N, 2°57′43′′ E) in an effort to characterize clouds in the continental free troposphere. Cloud droplets were sampled with single-stage cloud collectors (cut-off diameter approximately 7 µm) and analyzed for inorganic and organic ions, as well as total dissolved organic carbon. Results show a very large variability in chemical composition and total solute concentration of cloud droplets, ranging from a few mg l<sup>-1</sup> to more than 150 mg l<sup>-1</sup>. Samplings can be classified in three different categories with respect to their total ionic content and relative chemical composition: background continental (BG, total solute content lower than 18 mg l<sup>-1</sup>), anthropogenic continental (ANT, total solute content from 18 to 50 mg l<sup>-1</sup>), and special events (SpE, total solute content higher than 50 mg l<sup>-1</sup>). The relative chemical composition shows an increase in anthropogenic-derived species (NO<sub>3</sub><sup>-</sup>, SO<sub>4</sub><sup>2-</sup> and NH<sub>4</sub><sup>+</sup>) from BG to SpE, and a decrease in dissolved organic compounds (ionic and non-ionic) that are associated with the anthropogenic character of air masses. <P style='line-height: 20px;'> We observed a high contribution of solute in cloud water derived from the dissolution of gas phase species in all cloud events. This was evident from large solute fractions of nitrate, ammonium and mono-carboxylic acids in cloud water, relative to their abundance in the aerosol phase. The comparison between droplet and aerosol composition clearly shows the limited ability of organic aerosols to act as cloud condensation nuclei. The strong contribution of gas-phase species limits the establishment of direct relationships between cloud water solute concentration and LWC that are expected from nucleation scavenging
Results and recommendations from an intercomparison of six Hygroscopicity-TDMA systems
The performance of six custom-built Hygrocopicity-Tandem Differential Mobility Analyser (H-TDMA) systems was investigated in the frame of an international calibration and intercomparison workshop held in Leipzig, February 2006. The goal of the workshop was to harmonise H-TDMA measurements and develop recommendations for atmospheric measurements and their data evaluation. The H-TDMA systems were compared in terms of the sizing of dry particles, relative humidity (RH) uncertainty, and consistency in determination of number fractions of different hygroscopic particle groups. The experiments were performed in an air-conditioned laboratory using ammonium sulphate particles or an external mixture of ammonium sulphate and soot particles. The sizing of dry particles of the six H-TDMA systems was within 0.2 to 4.2% of the selected particle diameter depending on investigated size and individual system. Measurements of ammonium sulphate aerosol found deviations equivalent to 4.5% RH from the set point of 90% RH compared to results from previous experiments in the literature. Evaluation of the number fraction of particles within the clearly separated growth factor modes of a laboratory generated externally mixed aerosol was done. The data from the H-TDMAs was analysed with a single fitting routine to investigate differences caused by the different data evaluation procedures used for each H-TDMA. The differences between the H-TDMAs were reduced from +12/-13% to +8/-6% when the same analysis routine was applied. We conclude that a common data evaluation procedure to determine number fractions of externally mixed aerosols will improve the comparability of H-TDMA measurements. It is recommended to ensure proper calibration of all flow, temperature and RH sensors in the systems. It is most important to thermally insulate the aerosol humidification unit and the second DMA and to monitor these temperatures to an accuracy of 0.2 degrees C. For the correct determination of external mixtures, it is necessary to take into account size-dependent losses due to diffusion in the plumbing between the DMAs and in the aerosol humidification unit.Peer reviewe
"A novel Whole Air Sample Profiler (WASP) for the quantification of volatile organic compounds in the boundary layer" published in Atmos. Meas. Tech., 6, 2703â2712, 2013
International audienceThe AMT executive editors received a complaint that the method presented in the paper by Mak et al. (2013) was largely based on an earlier invention by Pieter Tans (see e.g., the paper by Karion et al., 2010), but this earlier invention was not mentioned or referenced in the paper by Mak et al. (2013). For the AMT executive editors it is not possible to make a clear decision in this conflict. Unfortunately, it was also not possible to reach a consensus between the involved parties. This editorial note thus has two aims: 1. to make the readers of the paper by Mak et al. (2013) aware of this conflict
Three-year observations of halocarbons at the Nepal Climate Observatory at Pyramid (NCO-P, 5079 m a.s.l.) on the Himalayan range
A monitoring programme for halogenated climate-altering gases has been established in the frame of the SHARE EV-K<sup>2</sup>-CNR project at the Nepal Climate Laboratory â Pyramid in the Himalayan range at the altitude of 5079 m a.s.l. The site is very well located to provide important insights on changes in atmospheric composition in a region that is of great significance for emissions of both anthropogenic and biogenic halogenated compounds. Measurements are performed since March 2006, with grab samples collected on a weekly basis. The first three years of data have been analysed. After the identification of the atmospheric background values for fourteen halocarbons, the frequency of occurrence of pollution events have been compared with the same kind of analysis for data collected at other global background stations. The analysis showed the fully halogenated species, whose production and consumption are regulated under the Montreal Protocol, show a significant occurrence of "above the baseline" values, as a consequence of their current use in the developing countries surrounding the region, meanwhile the hydrogenated gases, more recently introduced into the market, show less frequent spikes. <br><br> Atmospheric concentration trends have been calculated as well, and they showed a fast increase, ranging from 5.7 to 12.6%, of all the hydrogenated species, and a clear decrease of methyl chloroform (â17.7%). The comparison with time series from other stations has also allowed to derive Meridional gradients, which are absent for long living well mixed species, while for the more reactive species, the gradient increases inversely with respect to their atmospheric lifetime. The effect of long range transport and of local events on the atmospheric composition at the station has been analysed as well, allowing the identification of relevant source regions the Northern half of the Indian sub-continent. Also, at finer spatial scales, a smaller, local contribution of forest fires from the Khumbu valley has been detected
An accreted continental terrane in Northwestern Peru
Cet article présente une étude paléomagnétique des échantillons de plusieurs formations du bassin de Lancones (province de Piura). Les auteurs formulent l'hypothÚse de l'accrétion d'une terrane sur la marge péruvienne au cours du Néocomien. Un régime de cisaillement aurait également produit des rotations in situ. L'évolution géodynamique du nord du Pérou est donc comparable aux processus observés sur les Andes septentrionales, en Equateu
Temporal and vertical variations of aerosol physical and chemical properties over West Africa: AMMA aircraft campaign in summer 2006
While the Sahelian belt in West Africa stretches in the border between the global hot-spots of mineral dust and biomass burning aerosols, the presence of West African Monsoon is expected to create significant vertical and temporal variations in the regional aerosol properties through transport and mixing of particles from various sources (mineral dust, biomass burning, sulfates, sea salt). In order to improve our understanding of the evolution of the aerosol-cloud system over such region across the onset of the summer monsoon, the French ATR-42 research aircraft was deployed in Niamey, Niger (13°30' N, 02°05' E) in summer 2006, during the three special observation periods (SOPs) of the African Monsoon Multidisciplinary Analysis (AMMA) project. These three SOPs covered both dry and wet periods before and after the onset of the Western African Monsoon. <br><br> State of the art physico-chemical aerosol measurements on the ATR-42 showed a notable seasonal transition in averaged number size distributions where (i) the Aitken mode is dominating over the accumulation mode during the dry season preceding the monsoon arrival and (ii) the accumulation mode increasingly gained importance after the onset of the West African monsoon and even dominated the Aitken mode after the monsoon had fully developed. The parameters for the mean log-normal distributions observed in respective layers characterized by the different wind regimes (monsoon layer, SAL, free troposphere) are presented, together with the major particle compositions found in the accumulation mode particles. Thereby, results of this study should facilitate radiative transfer calculations, validation of satellite remote sensors, and detailed transport modeling by partners within and outside the AMMA community. <br><br> Extended analysis of the chemical composition of single aerosol particles by a transmission electron microscope (TEM) coupled to an energy dispersive X-ray spectrometer (EDX) revealed dominance of mineral dust (aluminosilicate) even in the submicron particle size range during the dry period, gradually replaced by prevailing biomass burning and sulfate particles, after the onset of the monsoon period. The spatial and temporal evolution from SOP1 to SOP2a1 and SOP2a2 of the particle physical and chemical properties and associated aerosol hygroscopic properties are remarkably consistent
Aerosol mass and black carbon concentrations, a two year record at NCO-P (5079 m, Southern Himalayas)
Aerosol mass and the absorbing fraction are important variables, needed to constrain the role of atmospheric particles in the Earth radiation budget, both directly and indirectly through CCN activation. In particular, their monitoring in remote areas and mountain sites is essential for determining source regions, elucidating the mechanisms of long range transport of anthropogenic pollutants, and validating regional and global models. Since March 2006, aerosol mass and black carbon concentration have been monitored at the Nepal Climate Observatory-Pyramid, a permanent high-altitude research station located in the Khumbu valley at 5079 m a.s.l. below Mt. Everest. The first two-year averages of PM<sub>1</sub> and PM<sub>1â10</sub> mass were 1.94 ÎŒg m<sup>â3</sup> and 1.88 ÎŒg m<sup>â3</sup>, with standard deviations of 3.90 ÎŒg m<sup>â3</sup> and 4.45 ÎŒg m<sup>â3</sup>, respectively, while the black carbon concentration average is 160.5 ng m<sup>â3</sup>, with a standard deviation of 296.1 ng m<sup>â3</sup>. Both aerosol mass and black carbon show well defined annual cycles, with a maximum during the pre-monsoon season and a minimum during the monsoon. They also display a typical diurnal cycle during all the seasons, with the lowest particle concentration recorded during the night, and a considerable increase during the afternoon, revealing the major role played by thermal winds in influencing the behaviour of atmospheric compounds over the high Himalayas. The aerosol concentration is subject to high variability: in fact, as well as frequent "background conditions" (55% of the time) when BC concentrations are mainly below 100 ng m<sup>â3</sup>, concentrations up to 5 ÎŒg m<sup>â3</sup> are reached during some episodes (a few days every year) in the pre-monsoon seasons. The variability of PM and BC is the result of both short-term changes due to thermal wind development in the valley, and long-range transport/synoptic circulation. At NCO-P, higher concentrations of PM<sub>1</sub> and BC are mostly associated with regional circulation and westerly air masses from the Middle East, while the strongest contributions of mineral dust arrive from the Middle East and regional circulation, with a special contribution from North Africa and South-West Arabian Peninsula in post-monsoon and winter season
In-cloud processes of methacrolein under simulated conditions â Part 3: Hygroscopic and volatility properties of the formed secondary organic aerosol
The hygroscopic and volatility properties of secondary organic aerosol (SOA) produced from the nebulization of solutions after aqueous phase photooxidation of methacrolein was experimentally studied in a laboratory, using a Volatility-Hygroscopicity Tandem DMA (VHTDMA). The obtained SOA were 80% 100&deg;C-volatile after 5 h of reaction and only 20% 100&deg;C-volatile after 22 h of reaction. The Hygroscopic Growth Factor (HGF) of the SOA produced from the nebulization of solutions after aqueous-phase photooxidation of methacrolein is 1.34â1.43, which is significantly higher than the HGF of SOA formed by gas-phase photooxidation of terpenes, usually found almost hydrophobic. These hygroscopic properties were confirmed for SOA formed by the nebulization of the same solutions where NaCl was added. The hygroscopic properties of the cloud droplet residuals decrease with the reaction time, in parallel with the formation of more refractory compounds. This decrease was mainly attributed to the 250&deg;C-refractive fraction (presumably representative of the highest molecular weight compounds), which evolved from moderately hygroscopic (HGF of 1.52) to less hygroscopic (HGF of 1.36). Oligomerization is suggested as a process responsible for the decrease of both volatility and hygroscopicity with time. The NaCl seeded experiments enabled us to show that 19&plusmn;4 mg L<sup>&minus;1</sup> of SOA was produced after 9.5 h of reaction and 41&plusmn;9 mg L<sup>&minus;1</sup> after 22 h of in-cloud reaction. Because more and more SOA is formed as the reaction time increases, our results show that the reaction products formed during the aqueous-phase OH-oxidation of methacrolein may play a major role in the properties of residual particles upon the droplet's evaporation. Therefore, the specific physical properties of SOA produced during cloud processes should be taken into account for a global estimation of SOA and their atmospheric impacts
Effects of mixing state on optical and radiative properties of black carbon in the European Arctic
Atmospheric aging promotes internal mixing of black carbon
(BC), leading to an enhancement of light absorption and radiative forcing.
The relationship between BC mixing state and consequent absorption
enhancement was never estimated for BC found in the
Arctic region. In the present work, we
aim to quantify the absorption enhancement and its impact on radiative
forcing as a function of microphysical properties and mixing state of BC
observed in situ at the Zeppelin Arctic station (78° N) in the
spring of 2012 during the CLIMSLIP (Climate impacts of short-lived pollutants
in the polar region) project.Single-particle soot photometer (SP2) measurements showed a mean mass
concentration of refractory black carbon (rBC) of 39 ng mâ3, while the
rBC mass size distribution was of lognormal shape, peaking at an rBC mass-equivalent diameter (DrBC) of around 240 nm. On average, the
number fraction of particles containing a BC core with
DrBC>80 nm was less than 5 % in the size range (overall
optical particle diameter) from 150 to 500 nm. The BC cores were internally
mixed with other particulate matter. The median coating thickness of BC cores
with 220 nm < DrBC<â260 nm was 52 nm, resulting
in a coreâshell diameter ratio of 1.4, assuming a coated sphere morphology.
Combining the aerosol absorption coefficient observed with an Aethalometer
and the rBC mass concentration from the SP2, a mass absorption cross section
(MAC) of 9.8 m2 gâ1 was inferred at a wavelength of 550 nm.
Consistent with direct observation, a similar MAC value (8.4 m2 gâ1
at 550 nm) was obtained indirectly by using Mie theory and assuming a
coated-sphere morphology with the BC mixing state constrained from the SP2
measurements. According to these calculations, the lensing effect is
estimated to cause a 54 % enhancement of the MAC compared to that of bare
BC particles with equal BC core size distribution. Finally, the ARTDECO
radiative transfer model was used to estimate the sensitivity of the
radiative balance to changes in light absorption by BC as a result of a varying
degree of internal mixing at constant total BC mass. The clear-sky noontime
aerosol radiative forcing over a surface with an assumed wavelength-dependent
albedo of 0.76â0.89 decreased, when ignoring the absorption enhancement, by
â0.12 W mâ2 compared to the base case scenario, which was constrained
with mean observed aerosol properties for the Zeppelin site in Arctic spring.
The exact magnitude of this forcing difference scales with environmental
conditions such as the aerosol optical depth, solar zenith angle and surface
albedo. Nevertheless, our investigation suggests that the absorption
enhancement due to internal mixing of BC, which is a systematic effect,
should be considered for quantifying the aerosol radiative forcing in the
Arctic region.</p
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