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1.
Artigo em Inglês | MEDLINE | ID: mdl-32397363

RESUMO

Purpose: Mexico's public hospitals are experiencing major operational problems which seriously affect the care of Mexican citizens. Some hospitals have initiated efforts to apply the Kaizen philosophy to improve this situation. Therefore, the purpose of this article is to analyze the methodological impact of Kaizen-Kata implementation in Mexican public hospitals that have tried to solve operational problems using this improvement approach. Design/Methodology/Approach: The service organization implemented Kaizen-Kata methodology in order to improve one operational problem-process in health care. A case-study approach was used in this research in order to understand the effects of the Kaizen-Kata methodology in solving problems in their operational procedures. Findings: Six specific drivers were identified when applying the Kaizen-Kata methodology. Furthermore, the impact on the levels of implementation of the Kaizen-Kata methodology in each of the improvement teams studied was also identified. Research Limitations: The main limitation of the research is that only three case-studies are presented thus it is not possible to generalize its results. Practical Implications (Where Possible): Other public hospitals can use this specific example as a working guide to solve the operational problems of health systems. Originality/Value: A methodology of continuous improvement in manufacturing was imported from the industry sector for application in an operational health care process. The Kaizen-Kata methodology contributed significantly to improving issues involving delays, customer complaints, process reworks and extra-cost, among other effects of operational problems.


Assuntos
Atenção à Saúde , Hospitais Públicos , Resolução de Problemas , Humanos , México , Saúde Pública
2.
BMC Evol Biol ; 13: 58, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23452908

RESUMO

BACKGROUND: The Neotropics are exceptionally diverse, containing roughly one third of all extant bird species on Earth. This remarkable species richness is thought to be a consequence of processes associated with both Andean orogenesis throughout the Tertiary, and climatic fluctuations during the Quaternary. Phylogeographic studies allow insights into how such events might have influenced evolutionary trajectories of species and ultimately contribute to a better understanding of speciation. Studies on continentally distributed species are of particular interest because different populations of such taxa may show genetic signatures of events that impacted the continent-wide biota. Here we evaluate the genealogical history of one of the world's most broadly-distributed and polytypic passerines, the rufous-collared sparrow (Zonotrichia capensis). RESULTS: We obtained control region DNA sequences from 92 Zonotrichia capensis individuals sampled across the species' range (Central and South America). Six additional molecular markers, both nuclear and mitochondrial, were sequenced for a subset of individuals with divergent control region haplotypes. Median-joining network analysis, and Bayesian and maximum parsimony phylogenetic analyses all recovered three lineages: one spanning Middle America, the Dominican Republic, and north-western South America; one encompassing the Dominican Republic, Roraima (Venezuela) and La Paz (Bolivia) south to Tierra del Fuego, Argentina; and a third, including eastern Argentina and Brazil. Phylogenetic analyses suggest that the Middle American/north-western South American clade is sister to the remaining two. Bayesian and maximum likelihood coalescent simulations used to study lineage demographic history, diversification times, migration rates and population expansion together suggested that diversification of the three lineages occurred rapidly during the Pleistocene, with negligible gene flow, leaving genetic signatures of population expansions. CONCLUSIONS: The Pleistocene history of the rufous-collared sparrow involved extensive range expansion from a probable Central American origin. Its remarkable morphological and behavioral diversity probably represents recent responses to local conditions overlying deeper patterns of lineage diversity, which are themselves produced by isolation and the history of colonization of South America.


Assuntos
Filogeografia , Aves Canoras/classificação , Aves Canoras/genética , Migração Animal , Animais , Evolução Biológica , Núcleo Celular/genética , DNA Mitocondrial/genética , Genética Populacional , Aves Canoras/anatomia & histologia , América do Sul
3.
BMC Evol Biol ; 7: 247, 2007 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-18154647

RESUMO

BACKGROUND: The forests of the upper Amazon basin harbour some of the world's highest anuran species richness, but to date we have only the sparsest understanding of the distribution of genetic diversity within and among species in this region. To quantify region-wide genealogical patterns and to test for the presence of deep intraspecific divergences that have been documented in some other neotropical anurans, we developed a molecular phylogeny of the wide-spread terrestrial leaflitter frog Eleutherodactylus ockendeni (Leptodactylidae) from 13 localities throughout its range in Ecuador using data from two mitochondrial genes (16S and cyt b; 1246 base pairs). We examined the relation between divergence of mtDNA and the nuclear genome, as sampled by five species-specific microsatellite loci, to evaluate indirectly whether lineages are reproductively isolated where they co-occur. Our extensive phylogeographic survey thus assesses the spatial distribution of E. ockendeni genetic diversity across eastern Ecuador. RESULTS: We identified three distinct and well-supported clades within the Ecuadorean range of E. ockendeni: an uplands clade spanning north to south, a northeastern and central lowlands clade, and a central and southeastern clade, which is basal. Clades are separated by 12% to 15% net corrected p-distance for cytochrome b, with comparatively low sequence divergence within clades. Clades marginally overlap in some geographic areas (e.g., Napo River basin) but are reproductively isolated, evidenced by diagnostic differences in microsatellite PCR amplification profiles or DNA repeat number and coalescent analyses (in MDIV) best modelled without migration. Using Bayesian (BEAST) and net phylogenetic estimates, the Southeastern Clade diverged from the Upland/Lowland clades in the mid-Miocene or late Oligocene. Lowland and Upland clades speciated more recently, in the early or late Miocene. CONCLUSION: Our findings uncover previously unsuspected cryptic species diversity within the common leaflitter frog E. ockendeni, with at least three different species in Ecuador. While these clades are clearly geographically circumscribed, they do not coincide with any existing landscape barriers. Divergences are ancient, from the Miocene, before the most dramatic mountain building in the Ecuadorean Andes. Therefore, this diversity is not a product of Pleistocene refuges. Our research coupled with other studies suggests that species richness in the upper Amazon is drastically underestimated by current inventories based on morphospecies.


Assuntos
Anuros/genética , Biodiversidade , Variação Genética , Filogenia , Animais , Anuros/classificação , Teorema de Bayes , Citocromos b/genética , DNA Mitocondrial/genética , Demografia , Equador , Frequência do Gene , Marcadores Genéticos , Haplótipos , Repetições de Microssatélites/genética , Especificidade da Espécie
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