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A review of daily conversations and practices at home: Exploring practices that promote early literacy in Spanish-speaking homes and home-school interactions
Coming from a low-income heritage language family, like 17% of Latino families, entails important academic risk factors related to lower scores on reading tests. Considering that it is estimated that Latino students will represent 50% of the U.S. public schoolsâ population by 2050, their literacy learning must be supported adequately. The purpose of this literature review is to explore, from an ecocultural perspective, early literacy practices of low-income Spanish-speaking families and analyze the nature of literacy home-school interventions implemented for this group. The literature highlights non-traditional literacy practices that are strengths of the Latino families, such as a robust oral tradition focused on social cues, childrenâs engagement in written household chores, and the use of the Bible to pass values. Parents have mixed beliefs regarding literacy promotion: they do not feel prepared to support their children; thus, they support teachers as experts. Three types of home-school literacy interventions were found: printed material sharing; printed material exchange; family programs. As the literature posits, interventions should consider and be based on family beliefs, culture, and strengths; otherwise, effectivity and attrition are at risk. Moreover, new research should be conducted to bridge the gap regarding the role of family actors other than the mother, as well as the differences within the Latino community and immigrant generation
Unsettling the culture panacea: the politics of cultural planning, national heritage and urban regeneration in Buenos Aires
Urban Simulation Models: Contributions as Analysis-Methodology in a Project of Urban Renewal
The recent urban transformations produced in cities indicate the need to propose new theoretical and methodological approaches in physical planning. Based on the idea of complexity, it is required to integrate, in the analysis, multiplicity of interrelated factors involved in urban development,moreover, to develop planning tools that can incorporate variables not initially considered (for example when the norms were sanctioned) and instruments that would provide assessment alternatives to planning decisions in real time. The simulation models are suggested as tools to detect the elements, relationships and the dynamics in a simplified form that allow experiencing on the results. That is to say, a theoretical position on to a computer model is translated to investigate (in an experimental way) possible solutions derived from manipulating the variables, before the phenomenon is materialized. In the case of urban planning, this condition is of particular relevance, given the importance to anticipate unwanted effects in the intervention context that may arise when urban projects are built. The paper evaluates the application of a simulation methodology,based on the dynamics of systems and the application of software that can anticipate the effects of certain decisions in an urban renewal project in the city of CĂłrdoba, Argentina. It applies the General Systems Theory that is a contribution to the notion of complex thought and is trans-disciplinary. Based on the idea of complex and multidimensional city, the effects of a real estate development are analyzed and conclusions on the limits and possibilities of using this tool during the processes of urban management are provided.Fil: Marengo, Maria Cecilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de CĂłrdoba. Facultad de Arquitectura, Urbanismo y Diseño. Instituto de InvestigaciĂłn de la Vivienda; Argentin
Microbiome-gut-brain axis and toll-like receptors in parkinson\u2019s disease
Parkinson’s disease (PD) is a progressively debilitating neurodegenerative disease characterized by α-synucleinopathy, which involves all districts of the brain-gut axis, including the central, autonomic and enteric nervous systems. The highly bidirectional communication between the brain and the gut is markedly influenced by the microbiome through integrated immunological, neuroendocrine and neurological processes. The gut microbiota and its relevant metabolites interact with the host via a series of biochemical and functional inputs, thereby affecting host homeostasis and health. Indeed, a dysregulated microbiota-gut-brain axis in PD might lie at the basis of gastrointestinal dysfunctions which predominantly emerge many years prior to the diagnosis, corroborating the theory that the pathological process is spread from the gut to the brain. Toll-like receptors (TLRs) play a crucial role in innate immunity by recognizing conserved motifs primarily found in microorganisms and a dysregulation in their signaling may be implicated in α-synucleinopathy, such as PD. An overstimulation of the innate immune system due to gut dysbiosis and/or small intestinal bacterial overgrowth, together with higher intestinal barrier permeability, may provoke local and systemic inflammation as well as enteric neuroglial activation, ultimately triggering the development of alpha-synuclein pathology. In this review, we provide the current knowledge regarding the relationship between the microbiota-gut–brain axis and TLRs in PD. A better understanding of the dialogue sustained by the microbiota-gut-brain axis and innate immunity via TLR signaling should bring interesting insights in the pathophysiology of PD and provide novel dietary and/or therapeutic measures aimed at shaping the gut microbiota composition, improving the intestinal epithelial barrier function and balancing the innate immune response in PD patients, in order to influence the early phases of the following neurodegenerative cascade
The relationship between the feather tuft of the uropygial gland and terrestrial/aquatic birds
The birdÂŽs uropygial gland has a papilla in its caudal end and it can also show a feather tuft. These feathers may have a raquis or not. The purpose of our study was to compare the number, dimensions and types of the tuftÂŽs feathers in aquatic and terrestrial birds, as well as to investigate whether the potential differences are related or determined by their dissimilar habitats. The uropygial glands were removed and the tuftÂŽs feathers were extracted and then measured, prepared for magnifying glass observation and photo shoot. Aquatic birds were found to have not only a larger number of feathers in the tuft but also longer feathers than terrestrial birds. However, the length ratio between calamus/raquis was higher in terrestrial birds. Almost all the species under study presented the same type of feathers except for the three penguin species that showed a peculiar type. The differences found between the tuftÂŽs feathers of the studied species are related with the environment. Aquatic birds have a longer length of the feather tuft because they may produce a greater amount of secretion than terrestrial birds.Fil: Chiale, Maria Cecilia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂa de Vertebrados; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Montalti, Diego. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂa de Vertebrados; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
A case of partial leucism in the American Barn Owl (Tyto furcata) (Temminck, 1827), from Buenos Aires province, Argentina
The diverse colorations of a birdsâ plumage are due to either structural colors or pigments that are synthesized in specialized cells or incorporated through the diet. However, plumage color aberrations can occur; several cases of albinism and leucism have been reported for different bird species and some examples correspond to Strigiformes. A specimen of the American barn owl (Tyto furcata) with partial leucism was found in CarhuĂ©, Buenos Aires province. The plumage of its facial disc, tail and the ventral region was completely white; furthermore, the neck, and the primary and secondary remiges were pigmented although in a significantly lighter fashion than in normal-phenotype specimens. The rest of the body presented a normal pattern for the species.Fil: Chiale, Maria Cecilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Departamento CientĂfico ZoologĂa Vertebrados; ArgentinaFil: Pagano Luis Gerardo. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Departamento CientĂfico ZoologĂa Vertebrados; Argentina. Grupo Falco; Argentin
Chromosome complement and meiosis in three species of the Neotropical bug genus Antiteuchus (Heteroptera, Pentatomidae, Discocephalinae)
Orcein staining of spermatocytes was used to study the meiotic behavior of holocentric chromosomes in three member of the genus Antiteuchus (commonly known as stink bugs). We describe and illustrate the karyotype of Antiteuchus mixtus, A. sepulcralis and A. macraspis which were cytogenetically characterized as having a diploid number of 2n = 14 and an XY sex chromosome system showing pre-reductional meiosis for autosomes and post-reductional meiosis for sex chromosomes. These species were also shown to have a long diffuse stage during meiotic prophase I and aberrant harlequin-type meiocytes. The chiasma frequency was also analyzed for two of the three species studied.Fil: Lanzone, Cecilia. Universidade Federal de Pernambuco; Brasil. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Ăridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Ăridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Ăridas; ArgentinaFil: de Souza, Maria JosĂ©. Universidade Federal de Pernambuco; Brasi
C-banding, fluorescent staining and NOR location in holokinetic chromosomes of bugs of the Neotropical genus Antiteuchus (Heteroptera: Pentatomidae: Discocephalinae)
Different cytogenetic techniques including C-banding, base-specific fluorochromes and silver nitrate staining were used to compare the karyotypes of three species of bugs, representatives of the Neotropical genus Antiteuchus, namely A. mixtus, A. sepulcralis and A. macraspis. The species have holokinetic chromosomes which is typical of the Hemiptera, and their diploid chromosome number is 2n = 14 and they have an XX/XY (female/male) sex chromosome system. C-banding revealed telomeric blocks of constitutive heterochromatin in most chromosomes of these three species. In each species, CMA;-positive blocks were observed in the telomeric heterochromatin region of chromosome pair 1. This chromosome pair carried the nucleolar organizer region (NOR), which silver nitrate staining revealed is located in the telomeric heterochromatin. In contrast to the result obtained with CMA3, entire chromosome complement stained homogenously with DAPI, except for the telomeric region of pair 1, which remained unstained.Fil: Lanzone, Cecilia. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Ăridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Ăridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Ăridas; Argentina. Universidade Federal de Pernambuco; BrasilFil: de Souza, Maria JosĂ©. Universidade Federal de Pernambuco; Brasi
The ephemeral aesthetic of spontaneous design on the streets of SĂŁo Paulo, Brazil
There are few opportunities when the poor and prosperous can be spoken about with respect to the same, shared cultural experience. And yet, visual culture, and the design process that contributes to its materialisation in specific contexts, offers an opportunity to recognise a socially inclusive activity that reveals similarity rather than difference. This paper celebrates an ephemeral aesthetic that is appreciated by people at different ends of the economic, political and social spectrum. A mutual appreciation for the medium of collage differs only in terms of the environment within which the recycled object is eventually revealed. This paper explores some of these different contexts, and those who recognise and practise this phenomenon in a South American and European context. The conclusion of this speculative and exploratory study is that there is potential to develop this unique medium as an accessible and inclusive visual language, giving voice to those who often do not have the opportunity or the means to speak and be heard. Collage is recognised as a channel that mediates between social exclusion and inclusion when political and economic means have been exhausted. The resulting ephemeral aesthetic is proven to have visual appeal, satisfying low- and high-order human needs.
Keywords:
Bricolage; Ephemeral Aesthetic; Urban Poor; Human Need; Graphic Design</p
Power tariffs : caught between cost recovery and affordability
This is the first paper to build a comprehensive empirical picture of power pricing practices across Sub-Saharan Africa, based on a new database of tariff structures in 27 countries for the years 2004-2008. Using a variety of quantitative indicators, the paper evaluates the performance of electricity tariffs against four key policy objectives: recovery of historic power production costs, efficient signaling of future power production costs, affordability to low income households, and distributional equity. As regards cost recovery, 80 percent of the countries in the sample fully recover operating costs, while only around 30 percent of the countries are practicing full recovery of capital costs. However, due to the fact that future power development may be based on a shift toward more economic technologies than those available in the past, existing tariffs look as though they would be consistent with Long Run Marginal Costs in nearly 40 percent of countries and hence provide efficient pricing signals. As regards affordability, today's average effective tariffs are affordable for 90 percent of today's customers. However, they would only be affordable for 25 percent of households that remain unconnected to the grid. Tariffs consistent with full recovery of economic costs would be affordable for 70 percent of the population. As regards equity, the highly regressive patterns of access to power services, ensure that subsidies delivered through electricity tariffs are without exception also highly regressive in distributional incidence. The conclusion is that achieving all four of these policy objectives simultaneously is almost impossible in the context of the high-cost low-income environment that characterizes much of SSA today. Hence most countries find themselves caught between cost recovery and affordability.International Trade and Trade Rules,Energy Production and Transportation,Infrastructure Economics,Debt Markets,Trade Policy
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