925 resultados para Improvement, reclamation, fertilisation, irrigation etc., of lands (Melioration)


Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study aims to address two research questions. First, ‘Can we identify factors that are determinants both of improved health outcomes and of reduced costs for hospitalized patients with one of six common diagnoses?’ Second, ‘Can we identify other factors that are determinants of improved health outcomes for such hospitalized patients but which are not associated with costs?’ The Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) database from 2003 to 2006 was employed in this study. The total study sample consisted of hospitals which had at least 30 patients each year for the given diagnosis: 954 hospitals for acute myocardial infarction (AMI), 1552 hospitals for congestive heart failure (CHF), 1120 hospitals for stroke (STR), 1283 hospitals for gastrointestinal hemorrhage (GIH), 979 hospitals for hip fracture (HIP), and 1716 hospitals for pneumonia (PNE). This study used simultaneous equations models to investigate the determinants of improvement in health outcomes and of cost reduction in hospital inpatient care for these six common diagnoses. In addition, the study used instrumental variables and two-stage least squares random effect model for unbalanced panel data estimation. The study concluded that a few factors were determinants of high quality and low cost. Specifically, high specialty was the determinant of high quality and low costs for CHF patients; small hospital size was the determinant of high quality and low costs for AMI patients. Furthermore, CHF patients who were treated in Midwest, South, and West region hospitals had better health outcomes and lower hospital costs than patients who were treated in Northeast region hospitals. Gastrointestinal hemorrhage and pneumonia patients who were treated in South region hospitals also had better health outcomes and lower hospital costs than patients who were treated in Northeast region hospitals. This study found that six non-cost factors were related to health outcomes for a few diagnoses: hospital volume, percentage emergency room admissions for a given diagnosis, hospital competition, specialty, bed size, and hospital region.^

Relevância:

100.00% 100.00%

Publicador:

Resumo:

"Slow Learners" is a term used to describe children with an IQ range of 70-89 on a standardized individual intelligence test (i.e. with a standard deviation of either 15 or 16). They have above retarded, but below average intelligence and potential to learn. If the factors associated with the etiology of slow learning in children can be identified, it may be possible to hypothesize causal relationships which can be tested by intervention studies specifically designed to prevent slow learning. If effective, these may ultimately reduce the incidence of school dropouts and their cost to society. To date, there is little information about variables which may be etiologically significant. In an attempt to identify such etiologic factors this study examines the sociodemographic characteristics, prenatal history (hypertension, smoking, infections, medication, vaginal bleeding, etc.), natal history (length of delivery, Apgar score, birth trauma, resuscitation, etc.), neonatal history (infections, seizures, head trauma, etc.), developmental history (health problems, developmental milestones and growth during infancy and early childhood), and family history (educational level of the parents, occupation, history of similar condition in the family, etc.) of a series of children defined as slow learners. The study is limited to children from middle to high socioeconomic families in order to exclude the possible confounding variable of low socioeconomic status, and because a descriptive study of this group has not been previously reported. ^

Relevância:

100.00% 100.00%

Publicador:

Resumo:

La gestión del agua de riego en la zona regable del Genil-Cabra, situada en la provincia de Córdoba, sur de España, se ha estudiado usando tres indicadores de riego: el Suministro Relativo de Agua de Riego (RIS); el Suministro Relativo de Agua (RWS) y el Suministro Relativo de Agua por Precipitaciones (RRS). Estos tres indicadores se han calculado tanto de forma global como agrupando los datos según el tipo de cultivo, el método de riego, la textura del suelo y el tamaño de la parcela. Toda la información relativa a variables agronómicas e hidráulicas se ha incluido en un Sistema de Información Geográfica (SIG) para facilitar su manejo. Los resultados muestran que los riegos son deficitarios ya que el valor del indicador RIS es relativamente bajo. No obstante, dado que el indicador RWS alcanza valores más altos, la demanda evaporativa puede ser satisfecha a lo largo del ciclo de desarrollo del cultivo. El indicador RRS oscila menos y junto al RWS permite conocer la fracción de evapotranspiración cubierta por el agua de lluvia. Los valores medios de los indicadores calculados son muy útiles para conocer el comportamiento del regante y la tendencia general, aunque la muestra usada es aún insuficiente para poder caracterizar una gran área de riego en su conjunto.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Introduction:Today, many countries, regardless of developed or developing, are trying to promote decentralization. According to Manor, as his quoting of Nickson’s argument, decentralization stems from the necessity to strengthen local governments as proxy of civil society to fill the yawning gap between the state and civil society (Manor [1999]: 30). With the end to the Cold War following the collapse of the Soviet Union rendering the cause of the “leadership of the central government to counter communism” meaningless, Manor points out, it has become increasingly difficult to respond flexibly to changes in society under the centralized system. Then, what benefits can be expected from the effectuation of decentralization? Litvack-Ahmad-Bird cited the four points: attainment of allocative efficiency in the face of different local preferences for local public goods; improvement to government competitiveness; realization of good governance; and enhancement of the legitimacy and sustainability of heterogeneous national states (Litvack, Ahmad & Bird [1998]: 5). They all contribute to reducing the economic and social costs of a central government unable to respond to changes in society and enhancing the efficiency of state administration through the delegation of authority to local governments. Why did Indonesia have a go at decentralization? As Maryanov recognizes, reasons for the implementation of decentralization in Indonesia have never been explicitly presented (Maryanov [1958]: 17). But there was strong momentum toward building a democratic state in Indonesia at the time of independence, and as indicated by provisions of Article 18 of the 1945 Constitution, there was the tendency in Indonesia from the beginning to debate decentralization in association with democratization. That said debate about democratization was fairly abstract and the main points are to ease the tensions, quiet the complaints, satisfy the political forces and thus stabilize the process of government (Maryanov [1958]: 26-27).    What triggered decentralization in Indonesia in earnest, of course, was the collapse of the Soeharto regime in May 1998. The Soeharto regime, regarded as the epitome of the centralization of power, became incapable of effectively dealing with problems in administration of the state and development administration. Besides, the post-Soeharto era of “reform (reformasi)” demanded the complete wipeout of the Soeharto image. In contraposition to the centralization of power was decentralization. The Soeharto regime that ruled Indonesia for 32 years was established in 1966 under the banner of “anti-communism.” The end of the Cold War structure in the late 1980s undermined the legitimate reason the centralization of power to counter communism claimed by the Soeharto regime. The factor for decentralization cited by Manor is applicable here.    Decentralization can be interpreted to mean not only the reversal of the centralized system of government due to its inability to respond to changes in society, as Manor points out, but also the participation of local governments in the process of the nation state building through the more positive transfer of power (democratic decentralization) and in the coordinated pursuit with the central government for a new shape of the state. However, it is also true that a variety of problems are gushing out in the process of implementing decentralization in Indonesia.    This paper discusses the relationship between decentralization and the formation of the nation state with the awareness of the problems and issues described above. Section 1 retraces the history of decentralization by examining laws and regulations for local administration and how they were actually implemented or not. Section 2 focuses on the relationships among the central government, local governments, foreign companies and other actors in the play over the distribution of profits from exploitation of natural resources, and examines the process of the ulterior motives of these actors and the amplification of mistrust spawning intense conflicts that, in extreme cases, grew into separation and independence movements. Section 3 considers the merits and demerits at this stage of decentralization implemented since 2001 and shed light on the significance of decentralization in terms of the nation state building. Finally, Section 4 attempts to review decentralization as the “opportunity to learn by doing” for the central and local governments in the process of the nation state building.    In the context of decentralization in Indonesia, deconcentration (dekonsentrasi), decentralization (desentralisasi) and support assignments (tugas pembantuan; medebewind, a Dutch word, was used previously) are defined as follows. Dekonsentrasi means that when the central government puts a local office of its own, or an outpost agency, in charge of implementing its service without delegating the administrative authority over this particular service. The outpost agency carries out the services as instructed by the central government. A head of a local government, when acting for the central government, gets involved in the process of dekonsentrasi. Desentralisasi, meanwhile, occurs when the central government cedes the administrative authority over a particular service to local governments. Under desentralisasi, local governments can undertake the particular service at their own discretion, and the central government, after the delegation of authority, cannot interfere with how local governments handle that service. Tugas pembantuan occur when the central government makes local governments or villages, or local governments make villages, undertake a particular service. In this case, the central government, or local governments, provides funding, equipment and materials necessary, and officials of local governments and villages undertake the service under the supervision and guidance of the central or local governments. Tugas pembantuan are maintained until local governments and villages become capable of undertaking that particular service on their own.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper investigates the impact of land rental market development on the efficiency of labor allocation and land utilization in rural China. To test the hypothesis that the shadow wage of a rent-in household with limited off-farm opportunities will increase with the development of a land rental market for households, a statistical comparison between the shadow wage and the estimated market wage was conducted. The results showed that the shadow wage for both rent-in households and non-rent-in households was significantly lower than the market wage, but that the wage for the rent-in households was statistically higher than that for non-rent-in households in Fenghua and Deqing, the two counties surveyed in this study. In addition, the estimated marginal product of farmland for rent-in households was statistically higher than the actual land rent that those households paid, while a null hypothesis that the actual rental fee accepted by rent-out households is equivalent to the marginal product of farmland for those households was not rejected in Fenghua county where land transactions by mutual agreement were more prevalent. These results indicate that the development of the land rental market facilitates the efficiency of labor allocation and farmland utilization in rural China.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Land conflicts in Rwanda have attracted particular attention because they have both environmental and political causes. This paper attempts to shed light on the nature of land conflicts in present-day Rwanda based on popular justice records and interviews collected in two rural areas. From the analyses of these data, two types of land confl ict can be distinguished. The first type consists of those among family members. Given that land is the most important asset for ordinary rural households, its inheritance often brings about conflicts between right-holders. Those of the second type are triggered by political change. Impacts of the two national-level violent conflicts in Rwanda, the “social revolution” just before independence and the civil war in the 1990s, are of tremendous significance in this context. The military victory of the former rebels in 1994 caused a massive return of Tutsi refugees, who were officially permitted to acquire land from the original inhabitants. Although no serious protestation against this policy has occurred thus far, it has produced various land conflicts. Dealing with potential grievances among original inhabitants is an important challenge for the present government.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

With over 700 million illiterate adults in the world, many governments have implemented adult literacy programs across the world, although typically with low rates of success partly because the quality of teaching is low. One solution may lie in the standardization of teaching provided by computer-aided instruction. We present the first rigorous evidence of the effectiveness of a computer-based adult literacy program. A randomized control trial study of TARA Akshar Plus, an Indian adult literacy program, was implemented in the state of Uttar Pradesh in India. We find large, significant impacts of this computer-aided program on literacy and numeracy outcomes. We compare the improvement in learning to that of other traditional adult literacy programs and conclude that TARA Akshar Plus is effective in increasing literacy and numeracy for illiterate adult women.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Nitrogen (N) is an important nutrient for melon (Cucumis melo L.) production. However there is scanty information about the amount necessary to maintain an appropriate balance between growth and yield. Melon vegetative organs must develop sufficiently to intercept light and accumulate water and nutrients but it is also important to obtain a large reproductive-vegetative dry weight ratio to maximize the fruit yield. We evaluated the influence of different N amounts on the growth, production of dry matter and fruit yield of a melon ‘Piel de sapo’ type. A three-year field experiment was carried out from May to September. Melons were subjected to an irrigation depth of 100% crop evapotranspiration and to 11 N fertilization rates, ranging 11 to 393 kg ha –1 in the three years. The dry matter production of leaves and stems increased as the N amount increased. The dry matter of the whole plant was affected similarly, while the fruit dry matter decreased as the N amount was increased above 112, 93 and 95 kg ha –1 , in 2005, 2006 and 2007, respectively. The maximum Leaf Area Index (LAI), 3.1, was obtained at 393 kg ha –1 of N. The lowest N supply reduced the fruit yield by 21%, while the highest increased the vegetative growth, LAI and Leaf Area Duration (LAD), but reduced yield by 24% relative to the N93 treatment. Excessive applications of N increase vegetative growth at the expense of reproductive growth. For this melon type, rates about 90-100 kg ha –1 of N are sufficient for adequate plant growth, development and maximum production. To obtain fruit yield close to the maximum, the leaf N concentration at the end of the crop cycle should be higher than 19.5 g kg –1

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper presents the results of applying DRAG methodology to the identification of the main factors of influence on the number of injury and fatal accidents occurring on Spain’s interurban network. Nineteen independent variables have been included in the model grouped together under ten categories: exposure, infrastructure, weather, drivers, economic variables, vehicle stock, surveillance, speed and legislative measures. Highly interesting conclusions can be reached from the results on the basis of the different effects of a single variable on each of the accident types according to severity. The greatest influence revealed by the results is exposure, which together with inexperienced drivers, speed and an ageing vehicle stock, have a negative effect, while the increased surveillance on roads, the improvement in the technological features of vehicles and the proportion of high capacity networks have a positive effect, since the results obtained show a significant drop in accidents.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Modernization of irrigation schemes, generally understood as transformation of surface irrigation systems into pressure –sprinkler and trickle- irrigation systems, aims at, among others, improving irrigation efficiency and reduction of operation and maintenance efforts made by the irrigators. However, pressure irrigation systems, in contrast, carry a serious energy cost. Energy requirements depend on decisions taken on management strategies during the operation phase, which are conditioned by previous decisions taken on the design project of the different elements which compose the irrigation system. Most of the countries where irrigation activity is significant bear in mind that modernization irrigation must play a key role in the agricultural infrastructure policies. The objective of this study is to characterize and estimate the mean and variation of the energy consumed by common types of irrigation systems and their management possibilities. The work includes all processes involved from the diversion of water into irrigation specific infrastructure to water discharge by the emitters installed on the crop fields. Simulation taking into account all elements comprising the irrigation system has been used to estimate the energy requirements of typical irrigation systems of several crop production systems. It has been applied to extensive and intensive crop systems, such us extensive winter crops, summer crops and olive trees, fruit trees and vineyards and intensive horticulture in greenhouses. The simulation of various types of irrigation systems and management strategies, in the framework imposed by particular cropping systems, would help to develop criteria for improving the energy balance in relation to the irrigation water supply productivity.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Mine soils usually contain large levels of heavy metals and poor fertility conditions which limit their reclamation and the application of phyto-remediation technologies. Two organic waste materials (pine bark compost and sheep and horse manure compost), with different pHs and varying degrees of humification and nutrient contents, were applied as amendments to assess their effects on copper (Cu) and zinc (Zn) bioavailability and on fertility conditions of mine soils. Soil samples collected from two abandoned mining areas near Madrid (Spain) were mixed with 0, 30 and 60 t ha?1 of the organic amendments. The concentrations of metals among the different mineral and organic fractions of soil were determined by several extraction procedures to study the metal distribution in the solid phase of the soil affected by the organic amendments. The results showed that the manure amendment increased the soil pH and the cation exchange capacity and enhanced the nutrient levels of these soils. The pine bark amendment decreased the soil pH and did not significantly change the nutrient status of soil. Soil pH, organic matter content and its degree of humification, which were altered by the amendments, were the main factors affecting Cu fractionation. Zn fractionation was mainly affected by soil pH. The addition of manure not only improved soil fertility, but also decreased metal bioavailability resulting in a reduction of metal toxicity. Conversely, pine bark amendment increased metal ioavailability. The use of sheep and horse manure could be a cost-effective practice for the restoration of contaminated mine soils.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Since the advent of the computer into the engineering field, the application of the numerical methods to the solution of engineering problems has grown very rapidly. Among the different computer methods of structural analysis the Finite Element (FEM) has been predominantly used. Shells and space structures are very attractive and have been constructed to solve a large variety of functional problems (roofs, industrial building, aqueducts, reservoirs, footings etc). In this type of structures aesthetics, structural efficiency and concept play a very important role. This class of structures can be divided into three main groups, namely continuous (concrete) shells, space frames and tension (fabric, pneumatic, cable etc )structures. In the following only the current applications of the FEM to the analysis of continuous shell structures will be discussed. However, some of the comments on this class of shells can be also applied to some extend to the others, but obviously specific computational problems will be restricted to the continuous shells. Different aspects, such as, the type of elements,input-output computational techniques etc, of the analysis of shells by the FEM will be described below. Clearly, the improvements and developments occurring in general for the FEM since its first appearance in the fifties have had a significative impact on the particular class of structures under discussion.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Ulmus minor es una especie arbórea originaria de Europa cuyas poblaciones han sido diezmadas por el hongo patógeno causante de la enfermedad de la grafiosis. La conservación de los olmos exige plantearse su propagación a través de plantaciones y conocer mejor su ecología y biología. Ulmus minor es un árbol de ribera, pero frecuentemente se encuentra alejado del cauce de arroyos y ríos, donde la capa freática sufre fuertes oscilaciones. Por ello, nuestra hipótesis general es que esta especie es moderadamente resistente tanto a la inundación como a la sequía. El principal objetivo de esta tesis doctoral es entender desde un punto de vista funcional la respuesta de U. minor a la inundación, la sequía y la infección por O. novo-ulmi; los factores que posiblemente más influyen en la distribución actual de U. minor. Con este objetivo se persigue dar continuidad a los esfuerzos de conservación de esta especie que desde hace años se dedican en varios centros de investigación a nivel mundial, ya que, entender mejor los mecanismos que contribuyen a la resistencia de U. minor ante la inoculación con O. novo-ulmi y factores de estrés abiótico ayudará en la selección y propagación de genotipos resistentes a la grafiosis. Se han planteado tres experimentos en este sentido. Primero, se ha comparado la tolerancia de brinzales de U. minor y U. laevis – otro olmo ibérico – a una inmersión controlada con el fin de evaluar su tolerancia a la inundación y comprender los mecanismos de aclimatación. Segundo, se ha comparado la tolerancia de brinzales de U. minor y Quercus ilex – una especie típica de ambientes Mediterránea secos – a la falta de agua en el suelo con el fin de evaluar el grado de tolerancia y los mecanismos de aclimatación a la sequía. El hecho de comparar dos especies contrastadas responde al interés en entender mejor cuales son los procesos que conducen a la muerte de una planta en condiciones de sequía – asunto sobre el que hay una interesante discusión desde hace algunos años. En tercer lugar, con el fin de entender mejor la resistencia de algunos genotipos de U. minor a la grafiosis, se han estudiado las diferencias fisiológicas y químicas constitutivas e inducidas por O. novo-ulmi entre clones de U. minor seleccionados a priori por su variable grado de resistencia a esta enfermedad. En el primer experimento se observó que los brinzales de U. minor sobrevivieron 60 días inmersos en una piscina con agua no estancada hasta una altura de 2-3 cm por encima del cuello de la raíz. A los 60 días, los brinzales de U. laevis se sacaron de la piscina y, a lo largo de las siguientes semanas, fueron capaces de recuperar las funciones fisiológicas que habían sido alteradas anteriormente. La conductividad hidráulica de las raíces y la tasa de asimilación de CO2 neta disminuyeron en ambas especies. Por el contrario, la tasa de respiración de hojas, tallos y raíces aumentó en las primeras semanas de la inundación, posiblemente en relación al aumento de energía necesario para desarrollar mecanismos de aclimatación a la inundación, como la hipertrofia de las lenticelas que se observó en ambas especies. Por ello, el desequilibrio del balance de carbono de la planta podría ser un factor relevante en la mortalidad de las plantas ante inundaciones prolongadas. Las plantas de U. minor (cultivadas en envases de 16 litros a media sombra) sobrevivieron por un prolongado periodo de tiempo en verano sin riego; la mitad de las plantas murieron tras 90 días sin riego. El cierre de los estomas y la pérdida de hojas contribuyeron a ralentizar las pérdidas de agua y tolerar la sequía en U. minor. Las obvias diferencias en tolerancia a la sequía con respecto a Q. ilex se reflejaron en la distinta capacidad para ralentizar la aparición del estrés hídrico tras dejar de regar y para transportar agua en condiciones de elevada tensión en el xilema. Más relevante es que las plantas con evidentes síntomas de decaimiento previo a su muerte exhibieron pérdidas de conductividad hidráulica en las raíces del 80% en ambas especies, mientras que las reservas de carbohidratos apenas variaron y lo hicieron de forma desigual en ambas especies. Árboles de U. minor de 5 y 6 años de edad (plantados en eras con riego mantenido) exhibieron una respuesta a la inoculación con O. novo-ulmi consistente con ensayos previos de resistencia. La conductividad hidráulica del tallo, el potencial hídrico foliar y la tasa de asimilación de CO2 neta disminuyeron significativamente en relación a árboles inoculados con agua, pero solo en los clones susceptibles. Este hecho enlaza con el perfil químico “más defensivo” de los clones resistentes, es decir, con los mayores niveles de suberina, ácidos grasos y compuestos fenólicos en estos clones que en los susceptibles. Ello podría restringir la propagación del hongo en el árbol y preservar el comportamiento fisiológico de los clones resistentes al inocularlos con el patógeno. Los datos indican una respuesta fisiológica común de U. minor a la inundación, la sequía y la infección por O. novo-ulmi: pérdida de conductividad hidráulica, estrés hídrico y pérdida de ganancia neta de carbono. Pese a ello, U. minor desarrolla varios mecanismos que le confieren una capacidad moderada para vivir en suelos temporalmente anegados o secos. Por otro lado, el perfil químico es un factor relevante en la resistencia de ciertos genotipos a la grafiosis. Futuros estudios deberían examinar como este perfil químico y la resistencia a la grafiosis se ven alteradas por el estrés abiótico. ABSTRACT Ulmus minor is a native European elm species whose populations have been decimated by the Dutch elm disease (DED). An active conservation of this species requires large-scale plantations and a better understanding of its biology and ecology. U. minor generally grows close to water channels. However, of the Iberian riparian tree species, U. minor is the one that spread farther away from rivers and streams. For these reasons, we hypothesize that this species is moderately tolerant to both flooding and drought stresses. The main aim of the present PhD thesis is to better understand the functional response of U. minor to the abiotic stresses – flooding and drought – and the biotic stress – DED – that can be most influential on its distribution. The overarching goal is to aid in the conservation of this emblematic species through a better understanding of the mechanisms that contribute to resistance to abiotic and biotic stresses; an information that can help in the selection of resistant genotypes and their expansion in large-scale plantations. To this end, three experiments were set up. First, we compared the tolerance to experimental immersion between seedlings of U. minor and U. laevis – another European riparian elm species – in order to assess their degree of tolerance and understand the mechanisms of acclimation to this stress. Second, we investigated the tolerance to drought of U. minor seedlings in comparison with Quercus ilex (an oak species typical of dry Mediterranean habitats). Besides assessing and understanding U. minor tolerance to drought at the seedling stage, the aim was to shed light into the functional alterations that trigger drought-induced plant mortality – a matter of controversy in the last years. Third, we studied constitutive and induced physiological and biochemical differences among clones of variable DED resistance, before and following inoculation with Ophiostoma novo-ulmi. The goal is to shed light into the factors of DED resistance that is evident in some genotypes of U. minor, but not others. Potted seedlings of U. minor survived for 60 days immersed in a pool with running water to approximately 2-3 cm above the stem collar. By this time, U. minor seedlings died, whereas U. laevis seedlings moved out of the pool were able to recover most physiological functions that had been altered by flooding. For example, root hydraulic conductivity and leaf photosynthetic CO2 uptake decreased in both species; while respiration initially increased with flooding in leaves, stems and roots possibly to respond to energy demands associated to mechanisms of acclimation to soil oxygen deficiency; as example, a remarkable hypertrophy of lenticels was soon observed in flooded seedlings of both species. Therefore, the inability to maintain a positive carbon balance somehow compromises seedling survival under flooding, earlier in U. minor than U. laevis, partly explaining their differential habitats. Potted seedlings of U. minor survived for a remarkable long time without irrigation – half of plants dying only after 90 days of no irrigation in conditions of high vapour pressure deficit typical of summer. Some mechanisms that contributed to tolerate drought were leaf shedding and stomata closure, which reduced water loss and the risk of xylem cavitation. Obviously, U. minor was less tolerant to drought than Q. ilex, differences in drought tolerance resulting mostly from the distinct capacity to postpone water stress and conduct water under high xylem tension among species. More relevant was that plants of both species exhibited similar symptoms of root hydraulic failure (i.e. approximately 80% loss of hydraulic conductivity), but a slight and variable depletion of non-structural carbohydrate reserves preceding dieback. Five- and six-year-old trees of U. minor (planted in the field with supplementary watering) belonging to clones of contrasted susceptibility to DED exhibited a different physiological response to inoculation with O. novo-ulmi. Stem hydraulic conductivity, leaf water potential and photosynthetic CO2 uptake decreased significantly relative to control trees inoculated with water only in DED susceptible clones. This is consistent with the “more defensive” chemical profile observed in resistant clones, i.e. with higher levels of saturated hydrocarbons (suberin and fatty acids) and phenolic compounds than in susceptible clones. These compounds could restrict the spread of O. novo-ulmi and contribute to preserving the near-normal physiological function of resistant trees when exposed to the pathogen. These results evidence common physiological responses of U. minor to flooding, drought and pathogen infection leading to xylem water disruption, leaf water stress and reduced net carbon gain. Still, seedlings of U. minor develop various mechanisms of acclimation to abiotic stresses that can play a role in surviving moderate periods of flood and drought. The chemical profile appears to be an important factor for the resistance of some genotypes of U. minor to DED. How abiotic stresses such as flooding and drought affect the capacity of resistant U. minor clones to face O. novo-ulmi is a key question that must be contemplated in future research.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

En todo el mundo se ha observado un crecimiento exponencial en la incidencia de enfermedades crónicas como la hipertensión y enfermedades cardiovasculares y respiratorias, así como la diabetes mellitus, que causa un número de muertes cada vez mayor en todo el mundo (Beaglehole et al., 2008). En concreto, la prevalencia de diabetes mellitus (DM) está aumentando de manera considerable en todas las edades y representa un serio problema de salud mundial. La diabetes fue la responsable directa de 1,5 millones de muertes en 2012 y 89 millones de años de vida ajustados por discapacidad (AVAD) (OMS, 2014). Uno de los principales dilemas que suelen asociarse a la gestión de EC es la adherencia de los pacientes a los tratamientos, que representa un aspecto multifactorial que necesita asistencia en lo relativo a: educación, autogestión, interacción entre los pacientes y cuidadores y compromiso de los pacientes. Medir la adherencia del tratamiento es complicado y, aunque se ha hablado ampliamente de ello, aún no hay soluciones “de oro” (Reviews, 2002). El compromiso de los pacientes, a través de la participación, colaboración, negociación y a veces del compromiso firme, aumentan las oportunidades para una terapia óptima en la que los pacientes se responsabilizan de su parte en la ecuación de adherencia. Comprometer e involucrar a los pacientes diabéticos en las decisiones de su tratamiento, junto con expertos profesionales, puede ayudar a favorecer un enfoque centrado en el paciente hacia la atención a la diabetes (Martin et al., 2005). La motivación y atribución de poder de los pacientes son quizás los dos factores interventores más relevantes que afectan directamente a la autogestión de la atención a la diabetes. Se ha demostrado que estos dos factores desempeñan un papel fundamental en la adherencia a la prescripción, así como en el fomento exitoso de un estilo de vida sana y otros cambios de conducta (Heneghan et al., 2013). Un plan de educación personalizada es indispensable para proporcionarle al paciente las herramientas adecuadas que necesita para la autogestión efectiva de la enfermedad (El-Gayar et al. 2013). La comunicación efectiva es fundamental para proporcionar una atención centrada en el paciente puesto que influye en las conductas y actitudes hacia un problema de salud ((Frampton et al. 2008). En este sentido, la interactividad, la frecuencia, la temporalización y la adaptación de los mensajes de texto pueden promover la adherencia a un régimen de medicación. Como consecuencia, adaptar los mensajes de texto a los pacientes puede resultar ser una manera de hacer que las sugerencias y la información sean más relevantes y efectivas (Nundy et al. 2013). En este contexto, las tecnologías móviles en el ámbito de la salud (mHealth) están desempeñando un papel importante al conectar con pacientes para mejorar la adherencia a medicamentos recetados (Krishna et al., 2009). La adaptación de los mensajes de texto específicos de diabetes sigue siendo un área de oportunidad para mejorar la adherencia a la medicación y ofrecer motivación a adultos con diabetes. Sin embargo, se necesita más investigación para entender totalmente su eficacia. Los consejos de texto personalizados han demostrado causar un impacto positivo en la atribución de poder a los pacientes, su autogestión y su adherencia a la prescripción (Gatwood et al., 2014). mHealth se puede utilizar para ofrecer programas de asistencia de autogestión a los pacientes con diabetes y, al mismo tiempo, superar las dificultades técnicas y financieras que supone el tratamiento de la diabetes (Free at al., 2013). El objetivo principal de este trabajo de investigación es demostrar que un marco tecnológico basado en las teorías de cambios de conducta, aplicado al campo de la mHealth, permite una mejora de la adherencia al tratamiento en pacientes diabéticos. Como método de definición de una solución tecnológica, se han adoptado un conjunto de diferentes técnicas de conducta validadas denominado marco de compromiso de retroacción conductual (EBF, por sus siglas en inglés) para formular los mensajes, guiar el contenido y evaluar los resultados. Los estudios incorporan elementos del modelo transteórico (TTM, por sus siglas en inglés), la teoría de la fijación de objetivos (GST, por sus siglas en inglés) y los principios de comunicación sanitaria persuasiva y eficaz. Como concepto general, el modelo TTM ayuda a los pacientes a progresar a su próxima fase de conducta a través de mensajes de texto motivados específicos y permite que el médico identifique la fase actual y adapte sus estrategias individualmente. Además, se adoptan las directrices del TTM para fijar objetivos personalizados a un nivel apropiado a la fase de cambio del paciente. La GST encierra normas que van a ponerse en práctica para promover la intervención educativa y objetivos de pérdida de peso. Finalmente, los principios de comunicación sanitaria persuasiva y eficaz aplicados a la aparición de los mensajes se han puesto en marcha para aumentar la efectividad. El EBF tiene como objetivo ayudar a los pacientes a mejorar su adherencia a la prescripción y encaminarlos a una mejora general en la autogestión de la diabetes mediante mensajes de texto personalizados denominados mensajes de retroacción automáticos (AFM, por sus siglas en inglés). Después de una primera revisión del perfil, consistente en identificar características significativas del paciente basadas en las necesidades de tratamiento, actitudes y conductas de atención sanitaria, el sistema elige los AFM personalizados, los aprueba el médico y al final se transfieren a la interfaz del paciente. Durante el tratamiento, el usuario recopila los datos en dispositivos de monitorización de pacientes (PMD, por sus siglas en inglés) de una serie de dispositivos médicos y registros manuales. Los registros consisten en la toma de medicación, dieta y actividad física y tareas de aprendizaje y control de la medida del metabolismo. El compromiso general del paciente se comprueba al estimar el uso del sistema y la adherencia del tratamiento y el estado de los objetivos del paciente a corto y largo plazo. El módulo de análisis conductual, que consiste en una serie de reglas y ecuaciones, calcula la conducta del paciente. Tras lograr el análisis conductual, el módulo de gestión de AFM actualiza la lista de AFM y la configuración de los envíos. Las actualizaciones incluyen el número, el tipo y la frecuencia de mensajes. Los AFM los revisa periódicamente el médico que también participa en el perfeccionamiento del tratamiento, adaptado a la fase transteórica actual. Los AFM se segmentan en distintas categorías y niveles y los pacientes pueden ajustar la entrega del mensaje de acuerdo con sus necesidades personales. El EBF se ha puesto en marcha integrado dentro del sistema METABO, diseñado para facilitar al paciente diabético que controle sus condiciones relevantes de una manera menos intrusiva. El dispositivo del paciente se vincula en una plataforma móvil, mientras que una interfaz de panel médico permite que los profesionales controlen la evolución del tratamiento. Herramientas específicas posibilitan que los profesionales comprueben la adherencia del paciente y actualicen la gestión de envíos de AFM. El EBF fue probado en un proyecto piloto controlado de manera aleatoria. El principal objetivo era examinar la viabilidad y aceptación del sistema. Los objetivos secundarios eran también la evaluación de la eficacia del sistema en lo referente a la mejora de la adherencia, el control glucémico y la calidad de vida. Se reclutaron participantes de cuatro centros clínicos distintos en Europa. La evaluación del punto de referencia incluía datos demográficos, estado de la diabetes, información del perfil, conocimiento de la diabetes en general, uso de las plataformas TIC, opinión y experiencia con dispositivos electrónicos y adopción de buenas prácticas con la diabetes. La aceptación y eficacia de los criterios de evaluación se aplicaron para valorar el funcionamiento del marco tecnológico. El principal objetivo era la valoración de la eficacia del sistema en lo referente a la mejora de la adherencia. En las pruebas participaron 54 pacientes. 26 fueron asignados al grupo de intervención y equipados con tecnología móvil donde estaba instalado el EBF: 14 pacientes tenían T1DM y 12 tenían T2DM. El grupo de control estaba compuesto por 25 pa cientes que fueron tratados con atención estándar, sin el empleo del EBF. La intervención profesional tanto de los grupos de control como de intervención corrió a cargo de 24 cuidadores, entre los que incluían diabetólogos, nutricionistas y enfermeras. Para evaluar la aceptabilidad del sistema y analizar la satisfacción de los usuarios, a través de LimeSurvey, se creó una encuesta multilingüe tanto para los pacientes como para los profesionales. Los resultados también se recopilaron de los archivos de registro generados en los PMD, el panel médico profesional y las entradas de la base de datos. Los mensajes enviados hacia y desde el EBF y los archivos de registro del sistema y los servicios de comunicación se grabaron durante las cinco semanas del estudio. Se entregaron un total de 2795 mensajes, lo que supuso una media de 107,50 mensajes por paciente. Como se muestra, los mensajes disminuyen con el tiempo, indicando una mejora global de la adherencia al plan de tratamiento. Como se esperaba, los pacientes con T1DM recibieron más consejos a corto plazo, en relación a su estado. Del mismo modo, al ser el centro de T2DM en cambios de estilo de vida sostenible a largo plazo, los pacientes con T2DM recibieron más consejos de recomendación, en cuanto a dietas y actividad física. También se ha llevado a cabo una comparación de la adherencia e índices de uso para pacientes con T1DM y T2DM, entre la primera y la segunda mitad de la prueba. Se han observado resultados favorables para el uso. En lo relativo a la adherencia, los resultados denotaron una mejora general en cada dimensión del plan de tratamiento, como la nutrición y las mediciones de inserción de glucosa en la sangre. Se han llevado a cabo más estudios acerca del cambio a nivel educativo antes y después de la prueba, medidos tanto para grupos de control como de intervención. Los resultados indicaron que el grupo de intervención había mejorado su nivel de conocimientos mientras que el grupo de control mostró una leve disminución. El análisis de correlación entre el nivel de adherencia y las AFM ha mostrado una mejora en la adherencia de uso para los pacientes que recibieron los mensajes de tipo alertas, y unos resultados no significativos aunque positivos relacionados con la adherencia tanto al tratamiento que al uso correlacionado con los recordatorios. Por otra parte, los AFM parecían ayudar a los pacientes que no tomaban suficientemente en serio su tratamiento en el principio y que sí estaban dispuestos a responder a los mensajes recibidos. Aun así, los pacientes que recibieron demasiadas advertencias, comenzaron a considerar el envío de mensajes un poco estresante. El trabajo de investigación llevado a cabo al desarrollar este proyecto ofrece respuestas a las cuatro hipótesis de investigación que fueron la motivación para el trabajo. • Hipótesis 1 : es posible definir una serie de criterios para medir la adherencia en pacientes diabéticos. • Hipótesis 2: es posible diseñar un marco tecnológico basado en los criterios y teorías de cambio de conducta mencionados con anterioridad para hacer que los pacientes diabéticos se comprometan a controlar su enfermedad y adherirse a planes de atención. • Hipótesis 3: es posible poner en marcha el marco tecnológico en el sector de la salud móvil. • Hipótesis 4: es posible utilizar el marco tecnológico como solución de salud móvil en un contexto real y tener efectos positivos en lo referente a indicadores de control de diabetes. La verificación de cada hipótesis permite ofrecer respuesta a la hipótesis principal: La hipótesis principal es: es posible mejorar la adherencia diabética a través de un marco tecnológico mHealth basado en teorías de cambio de conducta. El trabajo llevado a cabo para responder estas preguntas se explica en este trabajo de investigación. El marco fue desarrollado y puesto en práctica en el Proyecto METABO. METABO es un Proyecto I+D, cofinanciado por la Comisión Europea (METABO 2008) que integra infraestructura móvil para ayudar al control, gestión y tratamiento de los pacientes con diabetes mellitus de tipo 1 (T1DM) y los que padecen diabetes mellitus de tipo 2 (T2DM). ABSTRACT Worldwide there is an exponential growth in the incidence of Chronic Diseases (CDs), such as: hypertension, cardiovascular and respiratory diseases, as well as diabetes mellitus, leading to rising numbers of deaths worldwide (Beaglehole et al. 2008). In particular, the prevalence of diabetes mellitus (DM) is largely increasing among all ages and constitutes a major worldwide health problem. Diabetes was directly responsible for 1,5 million deaths in 2012 and 89 million Disability-adjusted life year (DALYs) (WHO 2014). One of the key dilemmas often associated to CD management is the patients’ adherence to treatments, representing a multi-factorial aspect that requires support in terms of: education, self-management, interaction between patients and caregivers, and patients’ engagement. Measuring adherence is complex and, even if widely discussed, there are still no “gold” standards ((Giardini et al. 2015), (Costa et al. 2015). Patient’s engagement, through participation, collaboration, negotiation, and sometimes compromise, enhance opportunities for optimal therapy in which patients take responsibility for their part of the adherence equation. Engaging and involving diabetic patients in treatment decisions, along with professional expertise, can help foster a patient-centered approach to diabetes care (Martin et al. 2005). Patients’ motivation and empowerment are perhaps the two most relevant intervening factors that directly affect self-management of diabetes care. It has been demonstrated that these two factors play an essential role in prescription adherence, as well as for the successful encouragement of a healthy life-style and other behavioural changes (Heneghan et al. 2013). A personalised education plan is indispensable in order to provide the patient with the appropriate tools needed for the effective self-management of the disease (El-Gayar et al. 2013). Effective communication is at the core of providing patient-centred care since it influences behaviours and attitudes towards a health problem (Frampton et al. 2008). In this regard, interactivity, frequency, timing, and tailoring of text messages may promote adherence to a medication regimen. As a consequence, tailoring text messages to patients can constitute a way of making suggestions and information more relevant and effective (Nundy et al. 2013). In this context, mobile health technologies (mHealth) are playing significant roles in improving adherence to prescribed medications (Krishna et al. 2009). The tailoring of diabetes-specific text messages remains an area of opportunity to improve medication adherence and provide motivation to adults with diabetes but further research is needed to fully understand their effectiveness. Personalized text advices have proven to produce a positive impact on patients’ empowerment, self-management, and adherence to prescriptions (Gatwood et al. 2014). mHealth can be used for offering self-management support programs to diabetes patients and at the same time surmounting the technical and financial difficulties involved in diabetes treatment (Free et al. 2013). The main objective of this research work is to demonstrate that a technological framework, based on behavioural change theories, applied to mHealth domain, allows improving adherence treatment in diabetic patients. The framework, named Engagement Behavioural Feedback Framework (EBF), is built on top of validated behavioural techniques to frame messages, guide the definition of contents and assess outcomes: elements from the Transtheoretical Model (TTM), the Goal-Setting Theory (GST), Effective Health Communication (EHC) guidelines and Principles of Persuasive Technology (PPT) were incorporated. The TTM helps patients to progress to a next behavioural stage, through specific motivated text messages, and allow clinician’s identifying the current stage and tailor its strategies individually. Moreover, TTM guidelines are adopted to set customised goals at a level appropriate to the patient’s stage of change. The GST was used to build rules to be applied for enhancing educational intervention and weight loss objectives. Finally, the EHC guidelines and the PPT were applied to increase the effectiveness of messages. The EBF aims to support patients on improving their prescription adherence and persuade them towards a general improvement in diabetes self-management, by means of personalised text messages, named Automatic Feedback Messages (AFM). After a first profile screening, consisting in identifying meaningful patient characteristics based on treatment needs, attitudes and health care behaviours, customised AFMs are selected by the system, approved by the professional, and finally transferred into the patient interface. During the treatment, the user collects the data into a Patient Monitoring Device (PMD) from a set of medical devices and from manual inputs. Inputs consist in medication intake, diet and physical activity, metabolic measurement monitoring and learning tasks. Patient general engagement is checked by estimating the usage of the system and the adherence of treatment and patient goals status in the short and the long term period. The Behavioural Analysis Module, consisting in a set of rules and equations, calculates the patient’s behaviour. After behavioural analysis is accomplished, the AFM library and the dispatch setting are updated by the AFM Manager module. Updates include the number, the type and the frequency of messages. The AFMs are periodically supervised by the professional who also participates to the refinement of the treatment, adapted to the current transtheoretical stage. The AFMs are segmented in different categories and levels and patients can adjust message delivery in accordance with their personal needs. The EBF was integrated to the METABO system, designed to facilitate diabetic patients in managing their disease in a less intrusive approach. Patient device corresponds in a mobile platform, while a medical panel interface allows professionals to monitoring the treatment evolution. Specific tools allow professional to check patient adherence and to update the AFMs dispatch management. The EBF was tested in a randomised controlled pilot. The main objective was to examine the feasibility and acceptance of the system. Secondary objectives were also the assessment of the effectiveness of system in terms of adherence improvement, glycaemic control, and quality of life. Participants were recruited from four different clinical centres in Europe. The baseline assessment included demographics, diabetes status, profile information, knowledge about diabetes in general, usage of ICT platforms, opinion and experience about electronic devices and adoption of good practices with diabetes. Acceptance and the effectiveness evaluation criteria were applied to evaluate the performance of the technological framework. The main objective was the assessment of the effectiveness of system in terms of adherence improvement. Fifty-four patients participated on the trials. Twenty-six patients were assigned in the intervention group and equipped with mobile where the EBF was installed: 14 patients were T1DM and 12 were T2DM. The control group was composed of 25 patients that were treated through a standard care, without the usage of the EBF. Professional’s intervention for both intervention and control groups was carried out by 24 care providers, including endocrinologists, nutritionists, and nurses. In order to evaluate the system acceptability and analyse the users’ satisfaction, an online multi-language survey, using LimeSurvey, was produced for both patients and professionals. Results were also collected from the log-files generated in the PMDs, the professional medical panel and the entries of the data base. The messages sent to and from the EBF and the log-files of the system and communication services were recorded over 5 weeks of the study. A total of 2795 messages were submitted, representing an average of 107,50 messages per patient. As demonstrated, messages decrease over time indicating an overall improvement of the care plan’s adherence. As expected, T1DM patients were more loaded with short-term advices, in accordance with their condition. Similarly, being the focus of T2DM on long-term sustainable lifestyle changes, T2DM received more reminders advices, as for diet and physical activity. Favourable outcomes were observed for treatment and usage adherences of the intervention group: for both the adherence indices, results denoted a general improvement on each care plan’s dimension, such as on nutrition and blood glucose input measurements. Further studies were conducted on the change on educational level before and after the trial, measured for both control and intervention groups. The outcomes indicated the intervention group has improved its level of knowledge, while the control group denoted a low decrease. The correlation analysis between the level of adherences and the AFMs showed an improvement in usage adherence for patients who received warnings message, while non-significantly yet even positive indicators related to both treatment and usage adherence correlated with the Reminders. Moreover, the AFMs seemed to help those patients who did not take their treatment seriously enough in the beginning and who were willing to respond to the messages they received. Even though, patients who received too many Warnings, started to consider the message dispatch to be a bit stressful. The research work carried out in developing this research work provides responses to the four research hypothesis that were the motivation for the work: •Hypothesis 1: It is possible to define a set of criteria to measure adherence in diabetic patients. •Hypothesis 2: It is possible to design a technological framework, based on the aforementioned criteria and behavioural change theories, to engage diabetic patients in managing their disease and adhere to care plans. •Hypothesis 3: It is possible to implement the technological framework in the mobile health domain. •Hypothesis 4: It is possible to use the technological framework as a mobile health solution in a real context and have positive effects in terms of diabetes management indicators. The verification of each hypothesis allowed us to provide a response to the main hypothesis: The Main Hypothesis is: It is possible to improve diabetic adherence through a mHealth technological framework based on behavioural change theories. The work carried out to answer these questions is explained in this research work. The framework was developed and applied in the METABO project. METABO is an R&D project, co-funded by the European Commission (METABO 2008) that integrates mobile infrastructure for supporting the monitoring, management, and treatment of type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) patients.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The role of nitric oxide (NO) in the pathogenesis of influenza virus-induced pneumonia in mice was investigated. Experimental influenza virus pneumonia was produced with influenza virus A/Kumamoto/Y5/67(H2N2). Both the enzyme activity of NO synthase (NOS) and mRNA expression of the inducible NOS were greatly increased in the mouse lungs; increases were mediated by interferon gamma. Excessive production of NO in the virus-infected lung was studied further by using electron spin resonance (ESR) spectroscopy. In vivo spin trapping with dithiocarbamate-iron complexes indicated that a significant amount of NO was generated in the virus-infected lung. Furthermore, an NO-hemoglobin ESR signal appeared in the virus-infected lung, and formation of NO-hemoglobin was significantly increased by treatment with superoxide dismutase and was inhibited by N(omega)-monomethyl-L-arginine (L-NMMA) administration. Immunohistochemistry with a specific anti-nitrotyrosine antibody showed intense staining of alveolar phagocytic cells such as macrophages and neutrophils and of intraalveolar exudate in the virus-infected lung. These results strongly suggest formation of peroxynitrite in the lung through the reaction of NO with O2-, which is generated by alveolar phagocytic cells and xanthine oxidase. In addition, administration of L-NMMA resulted in significant improvement in the survival rate of virus-infected mice without appreciable suppression of their antiviral defenses. On the basis of these data, we conclude that NO together with O2- which forms more reactive peroxynitrite may be the most important pathogenic factors in influenza virus-induced pneumonia in mice.