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1.
Chaos ; 34(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38848271

RESUMO

In the present article, we investigated a delay-based eco-epidemic prey-predator system in the presence of environmental fluctuations where predators engage with susceptible and infected prey, adopting Holling type II and ratio-dependent functional responses, respectively. During the study of the considered model, we identify each potential equilibrium point and its local stability criterion. The basic reproduction number has been computed, and the backward bifurcation about the disease-free equilibrium point was analyzed. The article illustrates Hopf bifurcation, global stability at the endemic equilibrium point, and their graphical depiction. We look over the variations in the dynamics of non-delay, delayed, and stochastic systems, revealing that a fixed level of temporal delay results in chaotic motion for the increasing strength of the saturation constant yet is potentially controlled by the predator growth rate. To study the dynamic behavior of the solution of the considered system and verify all theoretical results, we use numerical simulation and minutely analyze the influence of model parameters on the solution of the considered system. The stochastic transition is studied by varying the strength of stochastic fluctuation and the effect of delay.

4.
Lancet ; 382(9886): 65-99, 2013 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-23810020

RESUMO

Turkey has successfully introduced health system changes and provided its citizens with the right to health to achieve universal health coverage, which helped to address inequities in financing, health service access, and health outcomes. We trace the trajectory of health system reforms in Turkey, with a particular emphasis on 2003-13, which coincides with the Health Transformation Program (HTP). The HTP rapidly expanded health insurance coverage and access to health-care services for all citizens, especially the poorest population groups, to achieve universal health coverage. We analyse the contextual drivers that shaped the transformations in the health system, explore the design and implementation of the HTP, identify the factors that enabled its success, and investigate its effects. Our findings suggest that the HTP was instrumental in achieving universal health coverage to enhance equity substantially, and led to quantifiable and beneficial effects on all health system goals, with an improved level and distribution of health, greater fairness in financing with better financial protection, and notably increased user satisfaction. After the HTP, five health insurance schemes were consolidated to create a unified General Health Insurance scheme with harmonised and expanded benefits. Insurance coverage for the poorest population groups in Turkey increased from 2·4 million people in 2003, to 10·2 million in 2011. Health service access increased across the country-in particular, access and use of key maternal and child health services improved to help to greatly reduce the maternal mortality ratio, and under-5, infant, and neonatal mortality, especially in socioeconomically disadvantaged groups. Several factors helped to achieve universal health coverage and improve outcomes. These factors include economic growth, political stability, a comprehensive transformation strategy led by a transformation team, rapid policy translation, flexible implementation with continuous learning, and simultaneous improvements in the health system, on both the demand side (increased health insurance coverage, expanded benefits, and reduced cost-sharing) and the supply side (expansion of infrastructure, health human resources, and health services).


Assuntos
Reforma dos Serviços de Saúde/organização & administração , Cobertura Universal do Seguro de Saúde/organização & administração , Idoso , Governança Clínica , Feminino , Órgãos Governamentais , Reforma dos Serviços de Saúde/economia , Reforma dos Serviços de Saúde/tendências , Gastos em Saúde/tendências , Política de Saúde/economia , Política de Saúde/tendências , Serviços de Saúde/provisão & distribuição , Serviços de Saúde/tendências , Disparidades em Assistência à Saúde/tendências , Humanos , Lactente , Mortalidade Infantil/tendências , Seguro Saúde/economia , Seguro Saúde/organização & administração , Expectativa de Vida/tendências , Masculino , Mortalidade Materna/tendências , Pessoa de Meia-Idade , Direitos do Paciente , Satisfação do Paciente , Política , Turquia , Cobertura Universal do Seguro de Saúde/economia , Cobertura Universal do Seguro de Saúde/tendências
5.
Science ; 316(5828): 1185-8, 2007 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-17525337

RESUMO

The advent of biotechnology-derived, herbicide-resistant crops has revolutionized farming practices in many countries. Facile, highly effective, environmentally sound, and profitable weed control methods have been rapidly adopted by crop producers who value the benefits associated with biotechnology-derived weed management traits. But a rapid rise in the populations of several troublesome weeds that are tolerant or resistant to herbicides currently used in conjunction with herbicide-resistant crops may signify that the useful lifetime of these economically important weed management traits will be cut short. We describe the development of soybean and other broadleaf plant species resistant to dicamba, a widely used, inexpensive, and environmentally safe herbicide. The dicamba resistance technology will augment current herbicide resistance technologies and extend their effective lifetime. Attributes of both nuclear- and chloroplast-encoded dicamba resistance genes that affect the potency and expected durability of the herbicide resistance trait are examined.


Assuntos
Dicamba/farmacologia , Glycine max/efeitos dos fármacos , Herbicidas/farmacologia , Oxigenases de Função Mista/genética , Agricultura , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Cloroplastos/genética , Resistência a Medicamentos/genética , Engenharia Genética , Vetores Genéticos , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/genética , Oxigenases de Função Mista/metabolismo , Dados de Sequência Molecular , Oxirredutases O-Desmetilantes/metabolismo , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Pseudomonas/enzimologia , Pseudomonas/genética , Glycine max/genética , Nicotiana/efeitos dos fármacos , Nicotiana/genética
6.
Arch Biochem Biophys ; 437(1): 20-8, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15820213

RESUMO

Dicamba O-demethylase is a multicomponent enzyme that catalyzes the conversion of the herbicide 2-methoxy-3,6-dichlorobenzoic acid (dicamba) to 3,6-dichlorosalicylic acid (DCSA). The three components of the enzyme were purified and characterized. Oxygenase(DIC) is a homotrimer (alpha)3 with a subunit molecular mass of approximately 40 kDa. FerredoxinDIC and reductaseDIC are monomers with molecular weights of approximately 14 and 45 kDa, respectively. EPR spectroscopic analysis suggested the presence of a single [2Fe-2S](2+/1+) cluster in ferredoxinDIC and a single Rieske [2Fe-2S](2+; 1+) cluster within oxygenaseDIC. Consistent with the presence of a Rieske iron-sulfur cluster, oxygenaseDIC displayed a high reduction potential of E(m,7.0) = -21 mV whereas ferredoxinDIC exhibited a reduction potential of approximately E(m,7.0) = -171 mV. Optimal oxygenaseDIC activity in vitro depended on the addition of Fe2+. The identification of formaldehyde and DCSA as reaction products demonstrated that dicamba O-demethylase acts as a monooxygenase. Taken together, these data suggest that oxygenaseDIC is an important new member of the Rieske non-heme iron family of oxygenases.


Assuntos
Proteínas de Bactérias/química , Complexos Multienzimáticos/química , Oxirredutases O-Desmetilantes/química , Pseudomonas/enzimologia , Proteínas de Bactérias/isolamento & purificação , Clorobenzoatos , Dicamba/química , Ferredoxinas/química , Ferredoxinas/isolamento & purificação , Oxigenases de Função Mista/química , Oxigenases de Função Mista/isolamento & purificação , Complexos Multienzimáticos/isolamento & purificação , Oxirredução , Oxirredutases O-Desmetilantes/isolamento & purificação , Estrutura Quaternária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/isolamento & purificação , Salicilatos/química
7.
J Biol Chem ; 280(26): 24759-67, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15855162

RESUMO

Dicamba O-demethylase is a multicomponent enzyme from Pseudomonas maltophilia, strain DI-6, that catalyzes the conversion of the widely used herbicide dicamba (2-methoxy-3,6-dichlorobenzoic acid) to DCSA (3,6-dichlorosalicylic acid). We recently described the biochemical characteristics of the three components of this enzyme (i.e. reductase(DIC), ferredoxin(DIC), and oxygenase(DIC)) and classified the oxygenase component of dicamba O-demethylase as a member of the Rieske non-heme iron family of oxygenases. In the current study, we used N-terminal and internal amino acid sequence information from the purified proteins to clone the genes that encode dicamba O-demethylase. Two reductase genes (ddmA1 and ddmA2) with predicted amino acid sequences of 408 and 409 residues were identified. The open reading frames encode 43.7- and 43.9-kDa proteins that are 99.3% identical to each other and homologous to members of the FAD-dependent pyridine nucleotide reductase family. The ferredoxin coding sequence (ddmB) specifies an 11.4-kDa protein composed of 105 residues with similarity to the adrenodoxin family of [2Fe-2S] bacterial ferredoxins. The oxygenase gene (ddmC) encodes a 37.3-kDa protein composed of 339 amino acids that is homologous to members of the Phthalate family of Rieske non-heme iron oxygenases that function as monooxygenases. Southern analysis localized the oxygenase gene to a megaplasmid in cells of P. maltophilia. Mixtures of the three highly purified recombinant dicamba O-demethylase components overexpressed in Escherichia coli converted dicamba to DCSA with an efficiency similar to that of the native enzyme, suggesting that all of the components required for optimal enzymatic activity have been identified. Computer modeling suggests that oxygenase(DIC) has strong similarities with the core alphasubunits of naphthalene 1,2-dioxygenase. Nonetheless, the present studies point to dicamba O-demethylase as an enzyme system with its own unique combination of characteristics.


Assuntos
Oxirredutases O-Desmetilantes/química , Oxirredutases O-Desmetilantes/genética , Pseudomonas/enzimologia , Adrenodoxina/química , Sequência de Aminoácidos , Southern Blotting , Clorobenzoatos , Clonagem Molecular , Meios de Cultura , DNA/química , Primers do DNA/química , Dicamba/química , Eletroforese em Gel de Poliacrilamida , Escherichia coli/metabolismo , Ferredoxinas/química , Biblioteca Gênica , Ferro/química , Modelos Moleculares , Dados de Sequência Molecular , Oxirredutases/metabolismo , Oxigênio/química , Oxigenases/química , Oxigenases/metabolismo , Plasmídeos/metabolismo , Reação em Cadeia da Polimerase , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Salicilatos/química , Homologia de Sequência de Aminoácidos
8.
Soc Sci Med ; 55(9): 1579-87, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12297244

RESUMO

In many developing countries, private health practitioners provide a significant portion of curative care for diseases which are of public health importance. Currently, health sector reform efforts in these countries are fostering increased participation of private providers in the delivery of health services, including those of public health importance. Guaranteeing good technical quality of care is critical to the process. However, little is known about private providers' technical quality of care (disease management practices) and the factors influencing these services. The purpose of this study was to contribute information on this topic. The study was conducted among private providers in rural West Bengal, India and focused on providers' disease management practices for acute respiratory infections (ARI) among under-five children. World Health Organization (WHO) guidelines for ARI case management were used as the expected standard of care. Observations of patient-provider encounters and interviews with the providers and mothers were the main sources of data. The study found that private health providers in rural West Bengal have inadequate technical quality of care. The problem was related both to low levels of performance (limited potential) and inconsistency in performance (within-provider variation). Limited potential for good technical quality for ARI among the providers was related to lack of knowledge (technical incompetence). One of the important factors influencing within-provider variation was patient load. Since rural private providers operate on a fee-for-service payment system, there are incentives related to seeing many patients. The study concluded that to bring about sustainable improvements in private providers' ARI disease management practices, training programs and interventions that improved compliance were necessary.


Assuntos
Serviços de Saúde da Criança/normas , Competência Clínica , Gerenciamento Clínico , Prática Privada/normas , Qualidade da Assistência à Saúde , Infecções Respiratórias/terapia , Doença Aguda , Anti-Infecciosos/administração & dosagem , Administração de Caso/normas , Pré-Escolar , Países em Desenvolvimento , Características da Família , Pesquisa sobre Serviços de Saúde , Humanos , Índia , Entrevistas como Assunto , Guias de Prática Clínica como Assunto , Encaminhamento e Consulta , Infecções Respiratórias/tratamento farmacológico , Organização Mundial da Saúde
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