281 research outputs found
Structure of Equilenin at 100â K: an estrone-related steroid
The structure of the estrone-related steroid, Equilenin, C18H18O2 (systematic name 3-hy-droxy-13-methyl-11,12,13,14,15,16-hexa-hydro-cyclo-penta-[a]phen-anthren-17-one), has been determined at 100â
K. The crystals are ortho-rhom-bic, P212121, and the absolute structure of the mol-ecule in the crystal has been determined by resonant scattering [Flack parameter = -0.05â
(4)]. The C atoms of the A and B rings are almost coplanar, with an r.m.s. deviation from planarity of 0.0104â
Ă
. The C ring has a sofa conformation, while the D ring has an envelope conformation with the methine C atom as the flap. The keto O atom and the methyl group are translated 0.78 and 0.79â
Ă
, respectively, from the equivalent positions on 17ÎČ-estrone. In the crystal, mol-ecules are linked by O-HâŻO hydrogen bonds, forming chains parallel to the c-axis direction
Engineering robust polar chiral clathrate crystals
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ Royal Society of Chemistry 2013.The R-(+)-enantiomeric form of Dianin's compound and the S-(+)-enantiomeric form of its direct thiachroman analogue both obtained chromatographically employing a cellulose tris(3,5-dimethylphenylcarbamate) column, are shown to undergo supramolecular assembly to form a polar clathrate lattice which is stable even in the absence of a consolidating guest component
Crystalline inclusion of wheel-and-axle diol hosts featuring benzo[b]thiophene units as a lateral construction element
By applying the âwheel-and-axleâ host concept and incorporating a previously developed heteroaromatic substitution strategy, a new type of diol host featuring two di(benzo[b]thien-2-yl)hydroxymethyl units attached to both ends of a central ethynylene (3) and 1,4-phenylene (4) moiety is reported. The syntheses of the host compounds are described, and solvent inclusion formation via crystallization has extensively been studied showing a remarkable inclusion capability of the compounds. X-ray diffraction analysis of relevant crystal structures have been performed and comparatively discussed. Vapor sorption behavior of the compounds as solid receptor films coated on a quartz crystal microbalance considering a variety of solvent vapors has been scrutinized, indicating potential application as mass sensitive materials
Musashi interaction with poly(A) binding protein is required for activation of target mRNA translation
Fibula-related complications during bilateral tibial lengthening: 60 patients followed for mean 5 years
Active ageing, pensions and retirement in the UK
The ageing population has led to increasing concerns about pensions and their future
sustainability. Much of the dominant policy discourse around ageing and pension provision
over the last decade has focussed on postponing retirement and prolonging employment.
These measures are central to productive notions of âactive ageingâ. Initially the paper briefly
sets out the pension developments in the UK. Then it introduces active ageing and active
ageing policy, exploring its implications for UK pension provision. It demonstrates that a
more comprehensive active ageing framework, which incorporates a life-course perspective,
has the potential to assist the UK to respond to the challenges of an ageing population. In
doing so it needs to highlight older people as an economic and social resource, and reduce
barriers to older peopleâs participation in society
Understanding unequal ageing: towards a synthesis of intersectionality and life course analyses
Intersectionality has received an increasing amount of attention in health inequalities research in recent years. It suggests that treating social characteristics separatelyâmainly age, gender, ethnicity, and socio-economic positionâdoes not match the reality that people simultaneously embody multiple characteristics and are therefore potentially subject to multiple forms of discrimination. Yet the intersectionality literature has paid very little attention to the nature of ageing or the life course, and gerontology has rarely incorporated insights from intersectionality. In this paper, we aim to illustrate how intersectionality might be synthesised with a life course perspective to deliver novel insights into unequal ageing, especially with respect to health. First we provide an overview of how intersectionality can be used in research on inequality, focusing on intersectional subgroups, discrimination, categorisation, and individual heterogeneity. We cover two key approachesâthe use of interaction terms in conventional models and multilevel models which are particularly focussed on granular subgroup differences. In advancing a conceptual dialogue with the life course perspective, we discuss the concepts of roles, life stages, transitions, age/cohort, cumulative disadvantage/advantage, and trajectories. We conclude that the synergies between intersectionality and the life course hold exciting opportunities to bring new insights to unequal ageing and its attendant health inequalities
Tratamento cirĂșrgico de displasia de desenvolvimento do quadril de apresentação tardia depois da idade da marcha
Surface pretreatments for medical application of adhesion
Medical implants and prostheses (artificial hips, tendono- and ligament plasties) usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m). This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body
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