A three-phase axisymmetric numerical model based on Volume of Fluid–Continuum Surface Force (VOF–CSF) model was developed to perform parametric analysis of compound droplet production in three-phase glass capillary devices that combine co-flow and countercurrent flow focusing. The model predicted successfully generation of core–shell and multi-cored double emulsion droplets in dripping and jetting (narrowing and widening) regime and was used to investigate the effects of phase flow rates, fluid properties, and geometry on the size, morphology, and production rate of droplets. As the outer fluid flow rate increased, the size of compound droplets was reduced until a dripping-to-jetting transition occurred. By increasing the middle fluid flow rate, the size of compound droplets increased, which led to a widening jetting regime. The jetting was supressed by increasing the orifice size in the collection capillary or increasing the interfacial tension at the outer interface up to 0.06 N/m. The experimental and simulation results can be used to encapsulate CO2 solvents within gas-permeable microcapsules
A cross sectional, community-based, descriptive study among women of reproductive age group (15-49 years) in Nigeria to explore the possible reasons for contraceptive non-use despite reported high awareness was carried out. Data were obtained using a standard questionnaire instrument and applied on 2001 respondents. Contraceptive prevalence among sexually active respondents was 14.8% for all methods, 10.1% for modern methods and only 0.8% for emergency contraceptives. The most frequently stated reasons for non-use of contraceptives, among those who had never used any contraceptives but who did not want more children were: "did not think about it", "against religious belief " and "fear of side effects." Prior counseling significantly improved the continuation rate of contraception. Multivariate analysis showed that older, married and more educated women tended to use contraceptives more. Health-care providers should be trained to offer counseling services to all clients in general, and young, unmarried and uneducated women in particular in order to improve their acceptance of contraceptives. RÉSUMÉUne étude à base communautaire sur le comportement du contraceptif au Nigéria. Nous avons mené une étude descriptive traversale à base communautaaire auprès des femmes dans le group en âge d'avoir des enfants (15-19 ans) au Nigéria afin d'explorer les raisons qui peuvent expliquer le non-usage des contraceptifs malgré le haut niveau de sensibilisation. Les données ont été recueillies à l'aide d'un instrument de questionnaires standards administrés aux 2001 répondantes. La fréquence contraceptive parmi les répondants qui sont sexuellement actives était de 14,8% pour toutes les méthodes, 10,1% pour les méthodes modernes et juste 0,8% pour les contraceptifs d'urgence. Les raisons les plus fréquemment données pour expliquer le non-usage des contraceptifs parmi ceux qui n'ont jamais utilisé les contraceptifs, mais qui ne voulaient pas encore d'enfants étaient: "je n'y ai pensé", "contre la croyance religieuse" et "la peur des effets secondaires". L'analyse multifactorielle a montré que les femmes les plus âgées, mariées et instruites avaient la tendance d'utiliser les contraceptifs. Il faut former des prestataires de services médicaux pour qu'ils puissent rendre les services d'orientation à tous les clients en général, mais sourtout aux jeunes, aux célibataires et aux femmes non-instruites afin d'améliorer leur acceptance des contraceptifs. (Rev Afr Santé Reprod 2006; 10[2]:90-104)
BackgroundUnderstanding the sources of contraceptive commodities is an important aspect of the delivery of family planning services and is required by planning programme managers for strategic planning purposes. Findings from the 2003 Nigeria Demographic and Health Survey have previously showed that the private sector was the most frequently reported source of contraceptive supply, providing contraception to two and a half times as many women as the public sector. We conducted a community-based study to examine further the sources of contraceptive commodity for users in Nigeria with a view to identifying their preferences for distribution centres. This information would be useful to improve commodity distribution and to build the necessary capacity for satisfactory delivery of contraceptives.Methods and FindingsA multi-stage random sampling technique was used. A state was randomly selected to represent each of the four health zones in Nigeria. Two local government areas (LGAs) were then selected representing both urban and rural areas. Ten enumeration areas were subsequently selected from each LGA. Of the 2,001 respondents aged 15–49 years, 1,647 (82.3%) were sexually active, out of which 244 were found to be using contraceptive methods at the time of the study, giving a contraceptive prevalence of 14.8%. The commonest source of information on contraceptives was through friends (34%), followed by the radio (11.5%) and husbands (10.2%). Most respondents procured their contraceptives from chemist/patent medicine shops (19.7%), while only 0.8% obtained them from designated family planning clinics. The younger groups in this study (15–24 years), single people, Catholics, and Muslims, showed a greater preference for chemist/patent medicine shops for their sources of contraceptives. The older groups and married respondents, however, made use of government and private hospitals to obtain their contraceptives.ConclusionStrategies to increase contraceptive use must take into consideration these identified sources of contraceptives with a view to enhancing the quality, quantity, and variety of methods available, and to building capacity for effective service delivery. There is also a need to encourage the establishment of adolescent-friendly clinics where young people can go for counselling and obtain contraceptives of their choice, including emergency contraceptive pills.
Biodegradable poly(DL-lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA) microparticles with tunable size, shape, internal structure and surface morphology were produced by counter-current flow focusing in axisymmetric (3D) glass capillary devices. The dispersed phase was composed of 0.5-2 wt% polymer solution in a volatile 2 organic solvent (ethyl acetate or dichloromethane) and the continuous phase was 5 wt% aqueous poly(vinyl alcohol) solution. The droplets with a coefficient of variation in dripping regime below 2.5 % were evaporated to form polymeric particles with uniform sizes ranging between 4-30 µm. The particle microstructure and surface roughness were modified by adding nanofiller (montmorillonite nanoclay) or porogen (2-methylpentane) in the dispersed phase to form less porous polymer matrix or porous particles with golf-ball-like dimpled surface, respectively. The presence of 2-4 wt% nanoclay in the host polymer significantly reduced the release rate of paracetamol and prevented the early burst release, as a result of reduced polymer porosity and tortuous path for the diffusing drug molecules. Numerical modelling results using the volume of fluid-continuum surface force model agreed well with experimental behaviour and revealed trapping of nanoclay particles in the dispersed phase upstream of the orifice at low dispersed phase flow rates and for 4 wt% nanoclay content, due to vortex formation. Janus PLA/PCL (polycaprolactone) particles were produced by solvent evaporation-induced phase separation within organic phase droplets containing 3 % (v/v) PLA/PCL (30/70 or 70/30) mixture in dichloromethane. A strong preferential adsorption of Rhodamine 6G dye onto PLA was utilized to identify PLA portions of the Janus particles by Confocal Laser Scanning Microscopy (CLSM). Uniform hemispherical PCL particles were produced by dissolution of PLA domes with acetone.
The shell retained its integrity under isotonic conditions, but buckling and particle crumbling occurred in a hypertonic solution. When the capsules containing 5wt% aqueous Eudragit® S 100 solution in the core were incubated in 10M HCl solution, H diffused through the PLA film into the core causing an ionic gelation of the inner phase and its phase separation into polymer-rich and water-rich regions, due to the transition of Eudragit from a hydrophilic to hydrophobic state. Crescent-shaped composite microparticles with Eudragit cores and PLA shells were fabricated by drying core-shell microcapsules with gelled cores, due to the collapse of PLA shells encompassing water-rich crescent regions.
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