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To understand caregivers’ perceptions of children’s linear growth and to identify the cultural meanings and perceptions of risk associated with poor height attainment.
Three investigators from Bangladesh conducted twelve focus group discussions.
The study was conducted in rural and slum settings in Bangladesh.
Participants included mothers and alternative caregivers (n 81) who were recruited by household screening. No eligible, recruited subjects refused participation.
Caregivers reported limited experience with growth monitoring services from the health system. Caregivers mainly use visual cues and developmental milestones to understand if children are growing properly, and recognize that children normally experience both weight gain and linear growth with age. Mothers expressed concern over children’s malnutrition and short stature, but did not discuss children’s failure to attain a ‘growth potential’ or distinguish inherited short stature from stunting. Caregivers interpret the consequences of poor height attainment as primarily social and economic and cite few health risks.
Linear growth interpretation is determined more by community norms than by guidance from nutrition programming or the health system. Interventions to prevent or reduce linear growth failure may be perceived to have limited value where appropriate linear growth in children is determined by comparison to peers and siblings. Such perceptions may be significant barriers to programmes addressing stunting prevention in settings where many children are stunted. Efforts to raise awareness about the risks of linear growth faltering may need to consider delivering messages to caregivers that emphasize the social and economic consequences of stunting.
And thus it was with many things that I’m not going to repeat: commerce, market-determined prices in certain sectors, for certain activities; a proliferation of self-employment.…
And these are the opinions we have had about these things over the years,
never imagining that we would have to learn to live with them for a period
of time that is very difficult to predict, and that depends on many factors.
Fidel Castro, 23 April 1997
During the approximately 30 years in which the exercise of entrepreneurship in a market-oriented setting was effectively prohibited, Cuba actually created a nation of entrepreneurs. Although the intention was to convert Cuba into a “school for socialism,” the reality is that Cuba has also been, in part, a school for market-oriented entrepreneurship. This, indeed, is one of the more surprising and significant paradoxes of the Cuban Revolution. The nature of Cuba’s planned economy itself has inadvertently promoted widespread entrepreneurial values, attitudes, behavior, and savoir-faire, as citizens of necessity have had to buy and sell, truck and barter, hustle and “network” to improvise solutions to their personal economic problems. While entrepreneurial talents have developed broadly among the population, their exercise, until 1993, was restricted to the important but low-level everyday tasks of sustenance and survival, often carried out in the shadow or underground economy or on the black market. But when the space available for entrepreneurial activity was increased with the liberalization of microenterprise beginning in September 1993, the expansion and diversification of microentrepreneurial activity was impressive.
Since its “depenalization” in 1993, the U.S. dollar has become possibly a more significant component of Cuba's money supply than the old peso. What are the alternatives? The euro seems inappropriate, given the inevitability of eventual normalization of relations with the United States. More advantageous would be to restore the Cuban peso, though this would involve unifying the bifurcated economic structure and the dual monetary and exchange rate systems. The Cuban government has yet to announce its plans. This study argues that an appropriate mix of exchange rate, monetary, fiscal, and income or wage and salary policies should support a rehabilitation of the Cuban peso.
Cuba has entered the decade of the 1990s in a state of profound existential crisis. The countries of Eastern Europe, whose economic and political institutions and ideologies were adopted by Cuba, albeit with some modifications, were abandoning those same institutions and ideologies. Cuba's place in the international system had become one of growing isolation: Cuba had become a curiosity from the 1960s rather than the wave of the future, as it once perceived itself. By mid-1990, it appeared almost certain that the generous subsidization of the Cuban economy by the Soviet Union was about to end. Moreover, the Cuban economy was in serious difficulty as a result of some external factors, namely the convertible currency debt crisis and the problems and uncertainties in its relationship with the Soviet Union since 1985, but also as a result of internal institutional incapacities and deformities.
We present an in-depth study of metal-poor stars, based high resolution spectra combined with newly released astrometric data from Gaia, with special attention to observational uncertainties. The results are compared to those of other studies, including Gaia benchmark stars. Chemical evolution models are discussed, highlighting few puzzles that are still affecting our understanding of stellar nucleosynthesis and of the evolution of our Galaxy.
A combination of neutron diffraction, synchrotron X-ray diffraction, and high-resolution extended X-ray absorption fine structure measurements has been used to clarify the correlations between long- and local-range structural distortions across the spin-state transition in powders of LaCoO3 and La0.5Sr0.5Co0.75Nb0.25O3. The analysis of the diffraction data has revealed that the isotropic thermal parameters of Co–O bond abnormally increase below 100 K in both samples, while the temperature dependence of the average Co–O bond lengths is linear from 10 to 300 K. We also have found that the Co–O bond lengths are larger in La0.5Sr0.5Co0.75Nb0.25O3, as compared with the ones in LaCoO3. The X-ray absorption data showed an anomalous decrease of the Co–O bond lengths only for LaCoO3, in contrast to the bond length values obtained by diffraction. The structural anomalies observed by spectroscopy measurements are discussed in terms of the spin-state transition model.
Using the theoretically predicted mass spectrum of the white dwarfs (WDs) in zero-age cataclysmic binaries (ZACBs) by Politano and Webbink (1988), we examine to what extent observational selection can account for the observed high masses of the WDs in cataclysmic binaries (CBs).
The possible importance of the reaction of a low-mass star to external irradiation for the long-term evolution of compact binaries has been noted only rather recently; first in the context of the evolution of low-mass X-ray binaries (e.g. Podsiadlowski 1991; Harpaz & Rappaport 1991; Frank, King & Lasota 1992; Hameury et al. 1993) and subsequently by Ritter, Zhang & Kolb (1995a,b, hereafter RZK) also for the evolution of cataclysmic variables (CVs). Based on a simple model for describing the reaction of a low-mass star to irradiation RZK showed that CVs can be dynamically unstable against irradiation-induced mass transfer and that, as a consequence of this, mass transfer could occur via cycles in which phases of high, irradiation-enhanced mass transfer alternate with phases of little or no mass transfer. The occurrence of such mass transfer cycles in CVs was subsequently discussed from a more general point of view by King (1995) and King et al. (1995). Whereas the possibility of mass transfer cycles in CVs is now fully recognised, the question as to which systems can undergo such cycles and which cannot has not yet been addressed in detail. It is the purpose of this contribution to provide at least a partial answer to this question.
Structural measurements have been performed on the La0.7Sr0.3Mn3+0.85Nb5+0.15O3 compound with oxidation state of manganese close to +3. The composition undergoes a structural transition from rhombohedral to orthorhombic symmetry below room temperature. The calculated structural parameters show that the orthorhombic phase is not long-range orbitally ordered and that the structural transition is associated with a steric effect. The compound is ferromagnetic with a Curie point of around 150 K and a magnetic moment of 3.1 μB/Mn. It is suggested that ferromagnetism is originated from superexchange interactions via oxygen. Covalence enhances the positive part of the superexchange interactions whereas structural disorder leads to suppression of ferromagnetism.
Background and Purpose: Carotid artery stenting (CAS) has been, historically, an alternative to open endarterectomy (CEA) for stroke prevention in high risk patients with carotid atherosclerosis. We sought to determine the rates of periprocedural and long-term stroke or death and the risk factors for complications after CAS in our high risk patient population. Methods: Clinical and treatment variables of consecutive CAS procedures performed between 2002 and 2011 were analyzed. Using univariate and multivariate logistic regression analyses we examined how patient characteristics influenced outcomes and changes in modified Rankin Score (mRS). Results: In 152 patients, the composite total of periprocedural death, stroke, transient ischemic attack (TIA) and myocardial infarction (MI) rate was 3.95% (6/152). Chronic kidney disease (CKD) was strongly associated with periprocedural complications (p<0.001). Coronary artery disease/peripheral vascular disease (CAD/PVD) (p=0.03), dyslipidemia (p=0.02), CKD (p=0.01), and contralateral internal carotid artery stenosis (p=0.02) were non-modifiable risk factors for mRS increase. There were 25 deaths, 8 strokes, 11 TIAs, and 1 MI (mean follow-up 38.4 months, range 0-116 months). The presence of CAD/PVD (p=0.009) and dyslipidemia (p=0.002) were significantly associated with long-term complications. Conclusion: CAS was performed with low periprocedural complications in high-risk patients. Our rates compare very favorably to large-scale trials that have ideal patients. This data encourages the consideration of CAS in patients considered high risk for CEA and provides possible patient characteristics (CKD) to help with periprocedural risk stratification.
Complex Metallic Alloys (CMAs) are metallic solids of high structural complexity, consisting of large numbers of atoms in their unit cells. Consequences of this structural complexity are manifold and give rise to a variety of exciting physical properties. The impact that such structural complexity may have on the lattice dynamics will be discussed. The surprising dynamical flexibility of Tsai-type clusters with the symmetry breaking central tetrahedron will be addressed for Zn6Sc, while in the Ba-Ge-Ni clathrate system the dynamics of encaged Ba guest atoms in the surrounding Ge-Ni host framework is analysed with respect to the experimentally evidenced strong reduction of lattice thermal conductivity. For both systems experimental results from neutron scattering are analyzed and interpreted on atomistic scale by means of ab initio and molecular dynamics simulations, resulting in a picture with the respective structural building blocks as the origin of the peculiarities in the dynamics.
Synchrotron-based X-ray techniques are used increasingly to characterize actinide element speciation in heterogeneous media related to nuclear waste disposal safety. Especially techniques offering added temporal, spatial and energy resolved information are advancing our understanding of f-element physics and chemistry in general and of actinide element waste disposal in particular. Examples of investigations of uranium containing systems using both highly (energy) resolved X-ray emission spectroscopy (HRXES) techniques and spatially resolved techniques with focused X-ray beams are presented in this paper: polarization dependent partial fluorescence yield X-ray absorption near edge structure (PD-PFY-XANES) spectroscopic studies of a single Cs2UO2Cl4 crystal, which experimentally reveal a splitting of the σ, π, and δ components of the 6d valence states , and characterization of UO2/Mo thin films prepared on different substrates using a combination of techniques (2D and 3D micro- and nano-X-ray fluorescence, XANES and both holographic and ptychographic tomography).
Ionically self-assembled monolayer (ISAM) films are a recently developed class of materials that allows detailed structural and thickness control at the sub-nanometer level combined with ease of manufacturing and low cost. The ISAM fabrication method simply involves the dipping of a charged substrate alternately into polycationic and polyanionic aqueous solutions at room temperatures. Importantly, the ISAM technique yields exceptionally homogeneous, large area films with excellent control of total film thickness. We describe detailed studies of ISAM light emitting diodes incorporating poly(para-phenylene vinylene) (PPV) as the light emitting polymer. The individual thickness of each monolayer and the interpenetration of adjacent layers can be precisely controlled through the parameters of the electrolyte solutions. The effects of the pH and ionic strength of the immersion solutions, the total film thickness, and the PPV thermal conversion parameters on the photoluminescence and electroluminescence yields have been systematically studied. The ISAM process also allows the advantage of depositing well-defined thicknesses of separate polymers at the indium tin oxide and the aluminum electrode interfaces.