695 resultados para doubled haploid


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Institutions are widely regarded as important, even ultimate drivers of economic growth and performance. A recent mainstream of institutional economics has concentrated on the effect of persisting, often imprecisely measured institutions and on cataclysmic events as agents of noteworthy institutional change. As a consequence, institutional change without large-scale shocks has received little attention. In this dissertation I apply a complementary, quantitative-descriptive approach that relies on measures of actually enforced institutions to study institutional persistence and change over a long time period that is undisturbed by the typically studied cataclysmic events. By placing institutional change into the center of attention one can recognize different speeds of institutional innovation and the continuous coexistence of institutional persistence and change. Specifically, I combine text mining procedures, network analysis techniques and statistical approaches to study persistence and change in England’s common law over the Industrial Revolution (1700-1865). Based on the doctrine of precedent - a peculiarity of common law systems - I construct and analyze the apparently first citation network that reflects lawmaking in England. Most strikingly, I find large-scale change in the making of English common law around the turn of the 19th century - a period free from the typically studied cataclysmic events. Within a few decades a legal innovation process with low depreciation rates (1 to 2 percent) and strong past-persistence transitioned to a present-focused innovation process with significantly higher depreciation rates (4 to 6 percent) and weak past-persistence. Comparison with U.S. Supreme Court data reveals a similar U.S. transition towards the end of the 19th century. The English and U.S. transitions appear to have unfolded in a very specific manner: a new body of law arose during the transitions and developed in a self-referential manner while the existing body of law lost influence, but remained prominent. Additional findings suggest that Parliament doubled its influence on the making of case law within the first decades after the Glorious Revolution and that England’s legal rules manifested a high degree of long-term persistence. The latter allows for the possibility that the often-noted persistence of institutional outcomes derives from the actual persistence of institutions.

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The existence of genuinely non-geometric backgrounds, i.e. ones without geometric dual, is an important question in string theory. In this paper we examine this question from a sigma model perspective. First we construct a particular class of Courant algebroids as protobialgebroids with all types of geometric and non-geometric fluxes. For such structures we apply the mathematical result that any Courant algebroid gives rise to a 3D topological sigma model of the AKSZ type and we discuss the corresponding 2D field theories. It is found that these models are always geometric, even when both 2-form and 2-vector fields are neither vanishing nor inverse of one another. Taking a further step, we suggest an extended class of 3D sigma models, whose world volume is embedded in phase space, which allow for genuinely non-geometric backgrounds. Adopting the doubled formalism such models can be related to double field theory, albeit from a world sheet perspective.

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Background: The male germline in flowering plants differentiates by asymmetric division of haploid uninucleated microspores, giving rise to a vegetative cell enclosing a smaller generative cell, which eventually undergoes a second mitosis to originate two sperm cells. The vegetative cell and the sperm cells activate distinct genetic and epigenetic mechanisms to control pollen tube growth and germ cell specification, respectively. Therefore, a comprehensive characterization of these processes relies on efficient methods to isolate each of the different cell types throughout male gametogenesis. Results: We developed stable transgenic Arabidopsis lines and reliable purification tools based on Fluorescence-Activated Cell Sorting (FACS) in order to isolate highly pure and viable fractions of each cell/nuclei type before and after pollen mitosis. In the case of mature pollen, this was accomplished by expressing GFP and RFP in the sperm and vegetative nuclei, respectively, resulting in 99% pure sorted populations. Microspores were also purified by FACS taking advantage of their characteristic small size and autofluorescent properties, and were confirmed to be 98% pure. Conclusions: We provide simple and efficient FACS-based purification protocols for Arabidopsis microspores, vegetative nuclei and sperm cells. This paves the way for subsequent molecular analysis such as transcriptomics, DNA methylation analysis and chromatin immunoprecipitation, in the developmental context of microgametogenesis in Arabidopsis.

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This study presents two novel methods for treating important environmental contaminants from two different wastewater streams. One process utilizes the kinetic advantages and reliability of ion exchanging clinoptilolite in combination with biological treatment to remove ammonium from municipal sewage. A second process, HAMBgR (Hybrid Adsorption Membrane Biological Reactor), combines both ion exchange resin and bacteria into a single reactor to treat perchlorate contaminated waters. Combining physicochemical adsorptive treatment with biological treatment can provide synergistic benefits to the overall removal processes. Ion exchange removal solves some of the common operational reliability limitations of biological treatment, like slow response to environmental changes and leaching. Biological activity can in turn help reduce the economic and environmental challenges of ion exchange processes, like regenerant cost and brine disposal. The second section of this study presents continuous flow column experiments, used to demonstrate the ability of clinoptilolite to remove wastewater ammonium, as well as the effectiveness of salt regeneration using highly concentrated sea salt solutions. The working capacity of clinoptilolite more than doubled over the first few loading cycles, while regeneration recovered more than 98% of ammonium. Using the regenerant brine for subsequent halotolerant algae growth allowed for its repeated use, which could lead to cost savings and production of valuable algal biomass. The algae were able to uptake all ammonium in solution, and the brine was able to be used again with no loss in regeneration efficiency. This process has significant advantages over conventional biological nitrification; shorter retention times, wider range of operational conditions, and higher quality effluent free of nitrate. Also, since the clinoptilolite is continually regenerated and the regenerant is rejuvenated by algae, overall input costs are expected to be low. The third section of this study introduces the HAMBgR process for the elimination of perchlorate and presents batch isotherm experiments and pilot reactor tests. Results showed that a variety of ion-exchange resins can be effectively and repeatedly regenerated biologically, and maintain an acceptable working capacity. The presence of an adsorbent in the HAMBgR process improved bioreactor performance during operational fluctuations by providing a physicochemical backup to the biological process. Pilot reactor tests showed that the HAMBgR process reduced effluent perchlorate spikes by up to 97% in comparison to a conventional membrane bio-reactor (MBR) that was subject to sudden changes in influent conditions. Also, the HAMBgR process stimulated biological activity and lead to higher biomass concentrations during increased contaminant loading conditions. Conventional MBR systems can be converted into HAMBgR’s at a low cost, easily justifiable by the realized benefits. The concepts employed in the HAMBgR process can be adapted to treat other target contaminants, not just perchlorate.

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O presente Trabalho Final de Mestrado consiste na elaboração de um Estudo Prévio de um viaduto rodoviário, em betão armado pré-esforçado. O viaduto, com tabuleiro em laje vigada, é constituído por 10 tramos, prevendo-se que seja construído tramo a tramo, com juntas de betonagem a quintos de vão. A plataforma do viaduto é constituída por duas vias de tráfego com 3.5m cada, duas bermas de 1.00 m e dois passeios laterais com 1.10 m cada, perfazendo uma largura total de 11.20. O viaduto localiza-se em Polónia e foi dimensionado de acordo com os Eurocódigos e os Anexos Nacionais desse país.

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Epigenetic inheritance is more widespread in plants than in mammals, in part because mammals erase epigenetic information by germline reprogramming. We sequenced the methylome of three haploid cell types from developing pollen: the sperm cell, the vegetative cell, and their precursor, the postmeiotic microspore, and found that unlike in mammals the plant germline retains CG and CHG DNA methylation. However, CHH methylation is lost from retrotransposons in microspores and sperm cells and restored by de novo DNA methyltransferase guided by 24 nt small interfering RNA, both in the vegetative nucleus and in the embryo after fertilization. In the vegetative nucleus, CG methylation is lost from targets of DEMETER (DME), REPRESSOR OF SILENCING 1 (ROS1), and their homologs, which include imprinted loci and recurrent epialleles that accumulate corresponding small RNA and are premethylated in sperm. Thus genome reprogramming in pollen contributes to epigenetic inheritance, transposon silencing, and imprinting, guided by small RNA.

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The purpose of the current thesis is to develop a better understanding of the interaction between Spanish and Quichua in the Salcedo region and provide more information for the processes that might have given rise to Media Lengua, a ‘mixed’ language comprised of a Quichua grammar and Spanish lexicon. Muysken attributes the formation of Media Lengua to relexification, ruling out any influence from other bilingual phenomena. I argue that the only characteristic that distinguishes Media Lengua from other language contact varieties in central Ecuador is the quantity of the overall Spanish borrowings and not the type of processes that might have been employed by Quichua speakers during the genesis of Media Lengua. The results from the Salcedo data that I have collected show how processes such as adlexification, code-mixing, and structural convergence produce Media Lengua-type sentences, evidence that supports an alternative analysis to Muysken’s relexification hypothesis. Overall, this dissertation is developed around four main objectives: (1) to describe the variation of Spanish loanwords within a bilingual community in Salcedo; (2) to analyze some of the prominent and recent structural changes in Quichua and Spanish; (3) to determine whether Spanish loanword use can be explained by the relationship consultants have with particular social categories; and (4) to analyze the consultants’ language ideologies toward syncretic uses of Spanish and Quichua. Overall, 58% of the content words, 39% of the basic vocabulary, and 50% of the subject pronouns in the Salcedo corpus were derived from Spanish. When compared to Muysken’s description of highlander Quichua in the 1970’s, Spanish loanwords have more than doubled in each category. The overall level of Spanish loanwords in Salcedo Quichua has grown to a level between highlander Quichua in the 1970’s and Media Lengua. Similar to Spanish’s lexical influence in Media Lengua, the increase of Spanish borrowings in today’s rural Quichua can be seen in non-basic and basic vocabularies as well as the subject pronoun system. Significantly, most of the growth has occurred through forms of adlexification i.e., doublets, well-established borrowings, and cultural borrowings, suggesting that ‘ordinary’ lexical borrowing is also capable of producing Media Lengua-type sentences. I approach the second objective by investigating two separate phenomena related to structural convergence. The first examines the complex verbal constructions that have developed in Quichua through Spanish loan translations while the second describes the type of Quichua particles that are attached to Spanish lexemes while speaking Spanish. The calquing of the complex verbal constructions from Spanish were employed when speaking standard Quichua. Since this standard form is typically used by language purists, I argue that their use of calques is a strategy of exploiting the full range of expression from Spanish without incorporating any of the Spanish lexemes which would give the appearance of ‘contamination’. The use of Quichua particles in local varieties of Spanish is a defining characteristic of Quichuacized Spanish, spoken most frequently by women and young children in the community. Although the use of Quichua particles was probably not the main catalyst engendering Media Lengua, I argue that its contribution as a source language to other ‘mixed’ varieties, such as Media Lengua, needs to be accounted for in descriptions of BML genesis. Contrary to Muysken’s representation of relatively ‘unmixed’ Spanish and Quichua as the two source languages of Media Lengua, I propose that local varieties of Spanish might have already been ‘mixed’ to a large degree before Media Lengua was created. The third objective attempts to draw a relationship between particular social variables and the use of Spanish loanwords. Whisker Boxplots and ANOVAs were used to determine which social group, if any, have been introducing new Spanish borrowings into the bilingual communities in Salcedo. Specifically, I controlled for age, education, native language, urban migration, and gender. The results indicate that none of the groups in each of the five social variables indicate higher or lower loanword use. The implication of these results are twofold: (a) when lexical borrowing occurs, it is immediately adopted as the community-wide norm and spoken by members from different backgrounds and generations, or (b) this level of Spanish borrowing (58%) is not a recent phenomenon. The fourth and final objective draws on my ethnographic research that addresses the attitudes of syncretic language use. I observed that Quichuacized Spanish and Hispanicized Quichua are highly stigmatized varieties spoken by the country’s most marginalized populations and families, yet within the community, syncretic ways of speaking are in fact the norm. It was shown that there exists a range of different linguistic definitions for ‘Chaupi Lengua’ and other syncretic language practices as well as many contrasting connotations, most of which were negative. One theme that emerged from the interviews was that speaking syncretic varieties of Quichua weakened the consultant’s claim to an indigenous identity. The linguistic and social data presented in this dissertation supports an alternative view to Muysken’s relexification hypothesis, one that has the advantage of operating with well-precedented linguistic processes and which is actually observable in the present-day Salcedo area. The results from the study on lexical borrowing are significant because they demonstrate how a dynamic bilingual speech community has gradually diversified their Quichua lexicon under intense pressure to shift toward Spanish. They also show that Hispanicized Quichua (Quichua with heavy lexical borrowing) clearly arose from adlexification and prolonged lexical borrowing, and is one of at least six identifiable speech styles found in Salcedo. These results challenge particular interpretations of language contact outcomes, such as, ones that depict sources languages as discrete and ‘unmixed.’ The bilingual continuum presented in this thesis shows on the one hand, the range of speech styles that are accessible to different speakers, and on the other hand, the overlapping, syncretic features that are shared among the different registers and language varieties. It was observed that syncretic speech styles in Salcedo are employed by different consultants in varied interactional contexts, and in turn, produce different evaluations by other fellow community members. In the current dissertation, I challenge the claim that relexification and Media Lengua-type sentences develop in isolation and without the influence of other bilingual phenomena. Based on Muysken's Media Lengua example sentences and the speech styles from the Salcedo corpus, I argue that Media Lengua may have arisen as an institutionalized variant of the highly mixed "middle ground" within the range of the Salcedo bilingual continuum discussed above. Such syncretic forms of Spanish and Quichua strongly resemble Media Lengua sentences in Muysken’s research, and therefore demonstrate how its development could have occurred through several different language contact processes and not only through relexification.

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L’objectif de ce mémoire est d’identifier les déterminants de la générosité de l’aide sociale au Canada. Plus précisément, quels sont les facteurs qui expliquent les variations entre les montants d’aide sociale entre les provinces canadiennes de 1990 à 2009? Pourquoi le Québec, la Saskatchewan et Terre-Neuve-Labrador sont plus généreux que le Nouveau-Brunswick et l’Alberta? L’analyse de ces 10 politiques distinctes est produite à partir d’un cadre théorique quadripartite qui inclut le rôle des acteurs (partis politiques et syndicats), les traits institutionnels (dépenses publiques et engagement à la redistribution), les contraintes budgétaires (taux d’assistance sociale, dette, économie) et le rôle du gouvernement fédéral (montant et type de transfert). Les résultats démontrent que l’aide sociale est une politique hautement dépendante au sentier et incrémentale. Des transferts fédéraux à coût partagé et un taux de syndicalisation élevé sont des facteurs qui exercent une influence positive sur la générosité des provinces. À l’inverse, les partis de droite ainsi qu’une situation budgétaire difficile ont un impact négatif. Il faut noter que la richesse économique des provinces n’est pas associée à une plus grande générosité de l’aide sociale, au contraire les prestations d’aide sociale étaient plus faibles en 2009 qu’en 1990 malgré un PIB qui a presque doublé. De plus, des provinces riches comme l’Alberta et la Colombie-Britannique sont peu généreuses. Finalement, il faut noter que les partis politiques de gauche n’ont pas l’effet positif escompté sur la générosité des politiques de revenu minimum.

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Safeners are an important tool used to ensure the safe using of herbicide. The objective of this paper was to investigate the protective effect of four 3-dichloroacetyl oxazolidine safeners (3-dichloroacetyl-2,2-dimethyl-1,3-oxazolidine [R-28725], racemate of 3-dichloroacetyl-2,2-dimethyl-4- ethyl-1,3-oxazolidine, and its two chiral stereoisomers) in reducing the injury caused by imazethapyr. Physiological and biochemical tests were conducted under laboratory condition, by using seed treatment with safeners and soil treatment with imazethapyr, respectively. The interaction of two safeners (R-28725 and R-stereoisomer) and imazethapyr reduced the injury of maize significantly, and also increased glutathione content, activity of glutathione S-transferases, and activity of acetolactate synthase in maize. When induced by R-stereoisomer, the GSH content in root and in shoot increased 100.7% and 73.6%, respectively. When induced by R-28725, the GST activity in vivo increased threefold and the GST activity in vitro more than doubled. The kinetic parameter Vmax of GST in the maize treated with R-28725 and R-stereoisomer increased by 102.2% and 81.9%, respectively, compared with the control. The results also showed that R-28725 and R-stereoisomer induced glutathione S-transferases affinity for the substrate of conjugation reaction significantly.

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Small pelagic fishes are known to respond rapidly to changes in ocean climate. In this study, we evaluate the effects of future environmental warming (+2°C) during the early ontogeny of the European sardine, Sardina pilchardus. Warming reduced the survival of 30-day-old larvae by half. Length at hatching increased with temperature as expected, but no significant effect was observed on the length and growth at 30 days post-hatching. Warming did not significantly affect the thermal tolerance of sardine larvae, even though the mean lethal temperature increased by 1°C. In the warm conditions, sardine larvae showed signs of thermal stress, indicated by a pronounced increase in larval metabolism (Q 10 = 7.9) and a 45% increase in the heat shock response. Lipid peroxidation was not significantly affected by the higher temperature, even though the mean value doubled. Warming did not affect the time larvae spent swimming, but decreased by 36% the frequency of prey attacks. Given the key role of these small pelagics in the trophic dynamics off the Western Iberian upwelling ecosystem, the negative effects of warming on the early stages may have important implications for fish recruitment and ecosystem structure.

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Heme is an essential cofactor in numerous proteins, but is also cytotoxic. Thus, directed pathways must exist for regulating heme homeostasis. C. elegans is a powerful genetic animal model for elucidating these pathways because it is a heme auxotroph. Worms acquire dietary heme though HRG-1-related importers, and intestinal export was demonstrated to be mediated by the ABC transporter MRP-5. Loss of mrp-5 results in embryonic lethality. Although heme transporters have been identified, there are significant gaps in our understanding for the heme trafficking beyond HRG-1 and MRP-5. To identify additional components, we conducted a forward genetic screen utilizing the null allele mrp-5(ok2067). Screening of 160,000 haploid genomes yielded thirty-two mrp-5(ok2067) suppressor mutants. Deep-sequencing variant analysis revealed three of the suppressors subunits of adapter protein complex 3 (AP-3). We now seek to identify mechanisms for how adaptor protein deficiencies bypass a defect in MRP-5-mediated heme export.

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La información es poder o puede convertirse en poder. Por, este motivo el mundo se ha dividido en países ricos y países pobres también en cuanto a información se refiere. Costa Rica se ubica entre estos últimos porque no hemos logrado comprender el valor ni la forma de utilización de este poder. Somos ingenuos en uso porque duplicamos esfuerzos desperdiciamos capacidades, creamos una visión limitada de lo que es la información, no creamos un semillero de ciudadanos con capacidad para utilizarla en el futuro, no logramos utilizarla inteligentemente y no hemos logrado diseminar esta información con eficiencia.

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Artigo 1: Nos últimos 40 anos, a população idosa portuguesa duplicou, correspondendo a 16.7% da população total, prevendo-se que este índice venha a aumentar. De igual modo, o envelhecimento nos indivíduos com Dificuldade Intelectual e Desenvolvimental (DID) aumentou de uma forma considerável e segundo os Censos de 2011, 45.2% da população com DID tem idades entre os 45-90 anos, devido aos recentes avanços da tecnologia/medicina e das mudanças no estilo de vida, que permitiram um aumento da esperança média de vida (EMV) deste subgrupo populacional. Esta nova questão social trouxe repercussões significativas para as instituições, famílias e para os prestadores de cuidados, que passam a necessitar de recursos que contemplem o novo grupo populacional, os Gerontes com DID, i.e., serviços que não estejam segmentados e especializados para estes dois grupos populacionais, considerando-os como distintos. Na intervenção, em geral, e na intervenção psicomotora, em particular, é fundamental que se conheça o processo de envelhecimento nas pessoas com DID, para responder às novas necessidades e desafios emergentes decorrentes do mesmo. Desta forma, este artigo foca o processo de envelhecimento psicomotor desta população para uma melhor adequação dos programas a implementar, visando a melhoria das competências psicomotoras, aumento da autonomia e participação na comunidade. Artigo 2: O presente estudo apresenta como objetivo a avaliação das competências psicomotoras de gerontes com Dificuldade Intelectual e Desenvolvimental (DID), justificado pelo aumento considerável do seu tempo médio de vida, pela escassez de recursos direcionados e adequados e pelo desconhecimento das características psicomotoras do mesmo, durante o processo de envelhecimento. Foram divididos 118 gerontes, entre os 45 e os 94 anos (67.68 ± 13.09) em três grupos: 39 sem diagnóstico definido, 41 com doença de Alzheimer (DA) e 38 com DID e avaliados pelo Exame Geronto Psicomotor, que permitiu a definição dos seus perfis psicomotores. Na comparação dos grupos em estudo constatou-se as diferenças entre os grupos com DID/DA e os seus pares típicos na generalidade dos domínios, tal como seria expectável, apesar de ainda pouco se conhecer sobre a relação DA vs. DID. Recomenda-se, então, uma investigação mais detalhada, para intervenções individualizadas de qualidade e ainda uma possível adaptação do instrumento à DID.

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L’exacerbation de la perte d’autonomie des personnes âgées hospitalisées est fréquente. Le traumatisme craniocérébral (TCC) est une condition médicale associée à un état de stress et d’hypercatabolisme particulièrement élevé (Cook, 2008) qui rend la personne âgée encore plus vulnérable. De plus, les recommandations en vigueur pour l’apport protéique (0,8 g/kg) semblent insuffisantes pour freiner la perte de masse musculaire qui conduit à la sarcopénie. L’objectif de cette étude était de déterminer l’impact d’un supplément protéino-énergétique sur les performances physiques de la personne âgée traumatisée crânienne en réadaptation, plus spécifiquement sur la distance de marche, la force de préhension, ainsi que le test du « Time up and go » (TUG). Vingtquatre sujets, âgés de 65 à 94 ans (14 hommes) ont consenti à participer à cette étude randomisée contrôlée à double-aveugle dans un centre de réadaptation fonctionnelle intensive à Montréal. L’intervention consistait à ingérer un supplément nutritionnel (230 kcal, 15 g protéines, 25 g glucides) ou un placebo immédiatement après le traitement régulier de physiothérapie (45 à 60 minutes, 4 à 5 fois par semaine). Aucune différence significative n’a été trouvée dans les caractéristiques de base des 2 groupes. Une amélioration significative a été trouvée dans le groupe supplément pour le test du TUG. Notre étude d’intervention est la première en nutrition en sol québécois dans les Centres de réadaptation. La consommation d’un supplément chez la personne âgée durant le traitement de physiothérapie est une mesure simple et facile à introduire dans un contexte clinique. Même en l’absence de gains significatifs sur l’ensemble des mesures physiques, le supplément nutritionnel permet d’augmenter les apports caloriques et protéiques, ce qui peut contribuer à optimiser l’état nutritionnel. La littérature documente largement les impacts négatifs de la malnutrition et toute mesure pouvant contribuer à diminuer la prévalence de cette dernière ne peut donc qu’être positive.

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Over the past two decades the number of recorded disasters has doubled from approximately 200 to over 400 disasters per year. Such an increase in the frequency of disasters has not been without consequence, producing ever-greater waves of population displacements throughout the developing world. The United Nation’s Inter-Agency Standing Committee (IASC) responsible for the coordination of international humanitarian responses states unequivocally that populations displaced by disaster have a right to protection and the provision of basic necessities such as adequate food, water, clothing, sanitation, and essential health services (IASC, 2006 and The Sphere Project, 2011). Shelter responses are often a vital node around which many of these humanitarian concerns are addressed. This document is a review of 3 case studies, 6 field reports, 1 concept paper, 16 guidelines, 1 call for proposals, and 4 strategic framework documents prepared by organizations active in the humanitarian shelter sector on emergency and transitional shelters. While emergency shelter response is focused primarily on protection and relief during and immediately after a disaster has occurred, the transitional shelter approach emphasizes integrating disaster response into an immediate transition towards reconstruction, recovery, and sustainable development.