Higher grading conformal affine Toda theory and (generalized) sine-Gordon/massive Thirring duality

Some properties of the higher grading integrable generalizations of the conformal affine Toda systems are studied. The fields associated to the non-zero grade generators are Dirac spinors. The effective action is written in terms of the Wess-Zumino-Novikov-Witten (WZNW) action associated to an affine Lie algebra, and an off-critical theory is obtained as the result of the spontaneous breakdown of the conformal symmetry. Moreover, the off-critical theory presents a remarkable equivalence between the Noether and topological currents of the model. Related to the off-critical model we define a real and local lagrangian provided some reality conditions are imposed on the fields of the model. This real action model is expected to describe the soliton sector of the original model, and turns out to be the master action from which we uncover the weak-strong phases described by (generalized) massive Thirring and sine-Gordon type models, respectively. The case of any (untwisted) affine Lie algebra furnished with the principal gradation is studied in some detail. The example of s^l(n) (n = 2, 3) is presented explicitly. © SISSA/ISAS 2003.

Influência da espessura da camada de cimento e da variação da temperatura no comportamento mecânico de fragmentos cerâmicos utilizados em restaurações estéticas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estratégias de países sul-americanos na formação de recursos humanos para resposta ás emergências de saúde pública: exemplo dos programas de treinamento em epidemiologia de campo

Pós-graduação em Saúde Coletiva - FMB

Estratégias de países sul-americanos na formação de recursos humanos para resposta ás emergências de saúde pública: exemplo dos programas de treinamento em epidemiologia de campo

Pós-graduação em Saúde Coletiva - FMB

THE CONSTRUCTION PROCESS OF MANAGERIAL PROFILE COMPETENCIES FOR NURSE COORDINATORS IN THE HOSPITAL FIELD

The objective of this study was to construct a profile of managerial competencies, based on the consensus of nurse coordinators in the field. This study was developed in a philanthropic hospital in Sao Paulo, following the research-action model, and included 13 nurse coordinators as participants. The data collection was performed using the focal group technique. Data analysis was performed using the theoretical frameworks related to the working process and managerial competencies. The results identified the greater emphasis assigned to the competencies related to the mentor, coordinator and director roles. It was, therefore, possible to construct a professional development plan that is based on competencies in the technical, ethical-political, and communicative domains, as well as the development of citizenship. The analysis of the managerial working process and the study of the competencies within the managerial environment were shown to be important, because they highlighted the professionals' need to improve, thus fulfilling personal, professional, and organizational demands.

Bcl-2-homologe Proteine aus dem Schwamm Geodia cydonium

'Bcl-2-homologe Proteine aus dem Schwamm Geodia cydonium: Klonierung, Charakterisierung und Funktionsanalyse von Apoptose-Regulatoren der Porifera'. Auf der Suche nach der molekularbiologischen Grundlage der Apoptose in den Porifera, dem phylogenetisch ältesten Metazoen-Tierstamm, wurden Mitglieder der apoptoseregulatorischen Bcl?2 Familie unter Anwendung diverser Techniken im Schwamm G. cydonium identifiziert: GCBHP1 und GCBHP2. Detaillierte Analysen offenbarten Bcl-2-charakteristische Signaturen sowie eine durch apoptotische Stimuli induzierbare Expression. Die parallele HSP70-Induktion zeugte von der GCBHP2-Expression als Teil einer antiapoptotischen Streßantwort zum Schutz des Organismus'. Die kontinuierliche Transkription des im Rahmen dieser Arbeit gleichfalls klonierten Proliferationsmarkers SEP1 veranschaulichte zudem die Effektivität dieser Streßreaktion. Mit der Herstellung eines rekombinanten Proteins und der Gewinnung eines Antiserums konnte auch die streßinduzierte Proteinexpression des GCBHP2 verfolgt werden. Zum Zweck der Funktionsstudie wurden Säugetierzellen (HEK-293, NIH/3T3) mit einem GCBHP2-Konstrukt stabil transfiziert und auf die Expression des Schwammproteins untersucht. Diese Zellen unterschieden sich bereits phänotypisch von mock-transfizierten Zellen. Immunzytochemische Untersuchungen enthüllten eine für antiapoptotische Bcl-2 Proteine charakteristische Assoziation mit Mitochondrien. Unter dem Einfluß zweier apoptotischer Stimuli wurde für GCBHP2-transfizierte Zellen eine vierzehn-/sechsmal höhere Vitalität und eine reduzierte Aktivierung der Caspase-Kaskade registriert (im Vergleich zu mock-transfizierten Kontrollen). Somit wurde der antiapoptotische Charakter des GCBHP2 und die Existenz apoptotischer Mechanismen in den Porifera bestätigt.

Anwendung der geoelektrischen 3D-Tomographie für die Analyse thermisch induzierter Strömungen im Labor

Sowohl in der Natur als auch in der Industrie existieren thermisch induzierte Strömungen. Von Interesse für diese Forschungsarbeit sind dabei die Konvektionen im Erdmantel sowie in den Glasschmelzwannen. Der dort stattfindende Materialtransport resultiert aus Unterschieden in der Dichte, der Temperatur und der chemischen Konzentration innerhalb des konvektierenden Materials. Um das Verständnis für die ablaufenden Prozesse zu verbessern, werden von zahlreichen Forschergruppen numerische Modellierungen durchgeführt. Die Verifikation der dafür verwendeten Algorithmen erfolgt meist über die Analyse von Laborexperimenten. Im Vordergrund dieser Forschungsarbeit steht die Entwicklung einer Methode zur Bestimmung der dreidimensionalen Temperaturverteilung für die Untersuchung von thermisch induzierten Strömungen in einem Versuchsbecken. Eine direkte Temperaturmessung im Inneren des Versuchsmaterials bzw. der Glasschmelze beeinflusst allerdings das Strömungsverhalten. Deshalb wird die geodynamisch störungsfrei arbeitende Impedanztomographie verwendet. Die Grundlage dieser Methode bildet der erweiterte Arrhenius-Zusammenhang zwischen Temperatur und spezifischer elektrischer Leitfähigkeit. Während der Laborexperimente wird ein zähflüssiges Polyethylenglykol-Wasser-Gemisch in einem Becken von unten her erhitzt. Die auf diese Weise generierten Strömungen stellen unter Berücksichtigung der Skalierung ein Analogon sowohl zu dem Erdmantel als auch zu den Schmelzwannen dar. Über mehrere Elektroden, die an den Beckenwänden installiert sind, erfolgen die geoelektrischen Messungen. Nach der sich anschließenden dreidimensionalen Inversion der elektrischen Widerstände liegt das Modell mit der Verteilung der spezifischen elektrischen Leitfähigkeit im Inneren des Versuchsbeckens vor. Diese wird mittels der erweiterten Arrhenius-Formel in eine Temperaturverteilung umgerechnet. Zum Nachweis der Eignung dieser Methode für die nichtinvasive Bestimmung der dreidimensionalen Temperaturverteilung wurden mittels mehrerer Thermoelemente an den Beckenwänden zusätzlich direkte Temperaturmessungen durchgeführt und die Werte miteinander verglichen. Im Wesentlichen sind die Innentemperaturen gut rekonstruierbar, wobei die erreichte Messgenauigkeit von der räumlichen und zeitlichen Auflösung der Gleichstromgeoelektrik abhängt.

Observation and identification of metabolites emerging during postmortem decomposition of brain tissue by means of in situ 1H-magnetic resonance spectroscopy

Postmortem decomposition of brain tissue was investigated by (1)H-magnetic resonance spectroscopy (MRS) in a sheep head model and selected human cases. Aiming at the eventual estimation of postmortem intervals in forensic medicine, this study focuses on the characterization and identification of newly observed metabolites. In situ single-voxel (1)H-MRS at 1.5 T was complemented by multidimensional homo- and heteronuclear high-resolution NMR spectroscopy of an extract of sheep brain tissue. The inclusion of spectra of model solutions in the program LC Model confirmed the assignments in situ. The first postmortem phase was characterized mainly by changes in the concentrations of metabolites usually observed in vivo and by the appearance of previously reported decay products. About 3 days postmortem, new metabolites, including free trimethylammonium, propionate, butyrate, and iso-butyrate, started to appear in situ. Since the observed metabolites and the time course is comparable in sheep and human brain tissue, the model system seems to be appropriate.

Platinum-group, major, and trace element abundances in ODP Leg 183 basalts

Seventeen basalts from Ocean Drilling Program (ODP) Leg 183 to the Kerguelen Plateau (KP) were analyzed for the platinum-group elements (PGEs: Ir, Ru, Rh, Pt, and Pd), and 15 were analyzed for trace elements. Relative concentrations of the PGEs ranged from ~0.1 (Ir, Ru) to ~5 (Pt) times primitive mantle. These relatively high PGE abundances and fractionated patterns are not accounted for by the presence of sulfide minerals; there are only trace sulfides present in thin-section. Sulfur saturation models applied to the KP basalts suggest that the parental magmas may have never reached sulfide saturation, despite large degrees of partial melting (~30%) and fractional crystallization (~45%). First order approximations of the fractionation required to produce the KP basalts from an ~30% partial melt of a spinel peridotite were determined using the PELE program. The model was adapted to better fit the physical and chemical observations from the KP basalts, and requires an initial crystal fractionation stage of at least 30% olivine plus Cr-spinel (49:1), followed by magma replenishment and fractional crystallization (RFC) that included clinopyroxene, plagioclase, and titanomagnetite (15:9:1). The low Pd values ([Pd/Pt]_pm < 1.7) for these samples are not predicted by currently available Kd values. These Pd values are lowest in samples with relatively higher degrees of alteration as indicated by petrographic observations. Positive anomalies are a function of the behavior of the PGEs; they can be reproduced by Cr-spinel, and titanomagnetite crystallization, followed by titanomagnetite resorption during the final stages of crystallization. Our modeling shows that it is difficult to reproduce the PGE abundances by either depleted upper or even primitive mantle sources. Crustal contamination, while indicated at certain sites by the isotopic compositions of the basalts, appears to have had a minimal affect on the PGEs. The PGE abundances measured in the Kerguelen Plateau basalts are best modeled by melting a primitive mantle source to which was added up to 1% of outer core material, followed by fractional crystallization of the melt produced. This reproduces both the abundances and patterns of the PGEs in the Kerguelen Plateau basalts. An alternative model for outer core PGE abundances requires only 0.3% of outer core material to be mixed into the primitive mantle source. While our results are clearly model dependent, they indicate that an outer core component may be present in the Kerguelen plume source.

Modelo de integración del conocimiento-acción a través del Proyecto de Comunicación para el Desarrollo: 25 años de experiencia en comunidades indígenas andinas en Ecuador

El desarrollo como política de las naciones marca el período de la postguerra, que en América Latina se concreta en múltiples programas de Desarrollo Rural. El modelo inicial de crecimiento económico se va enriqueciendo con visiones centradas en el ser humano y sus múltiples concepciones de desarrollo. En este entender el desarrollo desde la diversidad cultural y antropológica de los pueblos de América Latina, surge la comunicación radiofónica como camino común para la persuasión, socialización y apropiación colectiva de conocimientos y ámbito participativo para consensuar objetivos y acordar actividades. El activismo de los años setenta y ochenta produjo un número considerable de experiencias. La mayoría de ellas han llegado hasta nuestros días, pero el giro tomado por las sociedades digitalizadas y las prioridades medioambientales han dado un nuevo rostro a aquellas primeras experiencias centradas en el desarrollo rural endógeno. Este estudio investiga el complejo práctico-teórico que integra comunicación y desarrollo en contextos territoriales interculturales con población marginal y aplicación de políticas de desarrollo rural. En el capítulo I se recogen las modalidades de cómo se ha aplicado la comunicación en programas de desarrollo, para profundizar en el concepto de comunicación para el desarrollo, conocer sus actores y resultados, y concluir que el desarrollo “con rostro humano” se hace con personas no con políticas oficiales. El capítulo II presenta a los Pueblos Indígenas de la Sierra Ecuatoriana como actores de su proceso de desarrollo hacia el Sumak Kawsay. Los temas tratados en este capítulo muestran los valores y capacidades de las comunidades indígenas de la Sierra Ecuatoriana para la autogestión de su desarrollo, y deja constancia y denuncia de la lectura negativa que se ha venido haciendo de su cosmovisión. Se encuentra respuesta conceptual y metodológica en el Workng With People para optimizar aportes culturales de los Pueblos Indígenas al proceso comunicacional y participativo para mejorar las condiciones de vida y lograr mayores espacios de autonomía y libertad El conocimiento que explica la realidad sin cambiarla no tiene sentido para los pobres. La realidad requiere ser comprendida para construir el conocimiento que la explique y la cambie: ese es el aporte del modelo conocimiento/acción que se presenta en el capítulo III. En este capítulo se exponen metodologías abiertas a la creatividad y flexibles que responden a los principios del modelo conocimiento/acción. La comunicación para el desarrollo se abre a todas ellas como ágora pluricultural que requiere un lenguaje común que se construye desde el aprendizaje social. Los conceptos expuestos en el capítulo III se vinculan en una propuesta metodológica que integra el conocimiento y la acción con los principios del Working With People, propuesta que se expone en el capítulo IV. El modelo del Proyecto de Comunicación para el Desarrollo junta en un modelo de comunicación popular y prácticas liberadoras con métodos cognitivos de la realidad para planificar el cambio desde la población y con la población. Finalmente, el capítulo V recoge la experiencia de la Casa Campesina Cayambe ejecutora del Proyecto de Comunicación para el Desarrollo en la adaptación ejecutada con Radio Mensaje. La riqueza de la experiencia tiende a escaparse de los límites conceptuales y los esquemas dejan espacios de vida ignotos; pero los conceptos y esquemas constituyen el camino para que la experiencia pase a ser objeto conocido y conocimiento socializado. El Proyecto de Comunicación para el Desarrollo es resultado de un proceso de desarrollo construido desde la acción de la Casa Campesina Cayambe durante 25 años en Cayambe. En el capítulo V se describe el contexto del territorio de Cayambe, la identidad de la Casa Campesina Cayambe y de Radio Mensaje, y termina describiendo los logros de 25 años trabajando con la gente. El estudio concluye que la comunicación participativa, como ámbito de aprendizaje social aplicado en procesos de desarrollo rural, integra el conocimiento/acción e incorpora nuevos conocimientos en la población con los que se desarrollan competencias locales para planificar el desarrollo endógeno con flexibilidad y de abajo-arriba. La Figura 0-1 grafica los elementos bases sobre los que se construye el proceso de desarrollo. ABSTRACT Development as a policy of nations marks the postwar period which created several Rural Development Programs in Latin America. The initial model of economic growth was enriched with approaches focused on human beings and their multiple conceptions of development. In this regard, the development from cultural and anthropological diversity in Latin America, radio communication emerges as a common means for persuasion, socialization and collective appropriation of knowledge and scope for participation in order to agree on objectives and activities. Activism of the seventies and eighties generated a considerable number of experiences, most of which are present today. However, a turn taken by digitalized societies and environmental priorities has given those first experiences which focused on endogenous rural development a new face. This study researches the theoretical-practical status that integrates communication and development in intercultural contexts with marginal population and the use of rural development policies. Chapter one shows the modalities of how communication in development programs have been applied to deepen the concept of communication for development, to know those who are involved and its findings, and conclude that development “with a human face” is done with people not with official policies. Chapter two presents Indigenous communities in the Ecuadorian highlands, as people involved in their development process towards Sumak Kawsay. The topics in this chapter show the values and capacities indigenous communities in the Ecuadorian highlands have to self-manage their development, and proves, as well as denounces, that their cosmovision has been negatively perceived. A conceptual and methodological response is found in Working With People in order to optimize cultural contributions of Indigenous People to the communicational and participative process to improve life conditions and have greater spaces of autonomy and freedom. Knowledge which explains reality without changing it does not make any sense for the poor. Reality need to be understood in order to build the knowledge that will explain it and change it: that is the contribution of the knowledge/action model presented in chapter three. This chapter presents open methodologies to creativity which are flexible to respond to the principles of the knowledge/action model. Communication for development is open to all of them as pluricultural agora which requires a common language that is built from social learning. The concepts presented in chapter three are linked in a methodological proposal which integrates knowledge and action with principles of Working With People, proposal which is presented chapter four. The model of the Communication for Development Project includes popular communication elements and liberating practices with cognitive methods of reality to plan change from the population and with the population. Finally, chapter five presents the experiences from the Cayambe Country House, which conducted the Communication for Development Project in the adaptation implemented with Radio Mensaje. The wealth of experience tends to scape from the conceptual limits and the schemes leave gaps of unexplored life; but the concepts and schemes constitute the way so that experience becomes a known object and socialized knowledge. The Communication for Development Project is the result of a development process built from the actions of the Cayambe Country House during 25 years in Cayambe. Chapter five describes the context of Cayambe, the identity of the Cayambe Country House and Radio Mensaje, and the achievements after 25 years of working with its people. The study concludes that participatory communication, as an area of social learning applied to rural development processes, integrates knowledge/action and incorporates new knowledge in communities to develop local competencies to plan endogenous development with flexibility and from the bottom – up.

Los espacios mineros abandonados. El caso de la Comunidad de Madrid

La Comunidad de Madrid ha tenido un pasado minero importante que ha dejado su vestigio en el territorio. Actualmente la explotación de minerales no metálicos y de rocas industriales y ornamentales continúa, pero no así la de la minería metálica que en el pasado fue abundante. Hoy en día todas estas minas están abandonadas, dando lugar a zonas degradadas con un elevado riesgo para la seguridad de las personas y de los animales terrestres que habitan por sus inmediaciones, y necesitan ser intervenidas atendiendo, además, a su integración o recuperación ecológica y paisajística en el territorio. El principal propósito de esta tesis es conocer la situación actual que presentan las minas abandonadas de metales y proponer unos modelos de actuación para la rehabilitación e integración de los espacios mineros abandonados de la Comunidad de Madrid, cuya ventaja también estriba en su posible extrapolación a otras aéreas de gestión con una problemática similar. Partiendo de una selección de cincuenta y siete minas de interior metálicas abandonadas, se ha hecho un diagnostico en función de su seguridad (riesgo), interés cultural, arqueológico e histórico y por su afección a espacios protegidos, resultando que en todas, excepto en tres de ellas, es preciso llevar a cabo medidas protectoras y de restauración e integración en el medio ambiente. El conjunto de minas catalogadas de alto riesgo para la seguridad son veintitrés, y sobre ellas se ha realizado un Análisis Clúster, en el que además de los criterios de gestión formulados: seguridad, protección del patrimonio minero-industrial e integración ecológico-paisajística, se han incorporado otros modificadores como distancia a poblaciones, caminos, pistas y vías pecuarias, y accesibilidad. Con los resultados de este análisis se obtienen una clasificación por grupos de las minas en relación con las características intrínsecas de las explotaciones preseleccionadas y la tipología de problemas que presentan, y a partir de ella se plantean soluciones viables que se concretan en la redacción de una serie de anteproyectos tipo. Una de las principales aportaciones es que se trata de un modelo de inventariocaracterización- actuación extrapolable a otros entornos similares con problemáticas parecidas. Las propuestas de actuación que figuran en los anteproyectos tipo se proponen como medidas aplicables en situaciones similares. La tesis además también incorpora una base de datos georreferenciada que permite la localización de las explotaciones mineras abandonadas, el acceso rápido a sus características y a la propuesta de restauración correspondiente. ABSTRACT The Community of Madrid had an important mining past that left its traces in the territory. Currently the explotation of non-metallic minerals and industrial and ornamental rocks continues, but not so much with the metal deposits that were abundant in the past. Today these mines are abandoned, resulting in degraded areas with a high risk to the safety of nearby people and animals that inhabit its vicinity, and they need to be intervened, by tending to their environment integration or ecological and landscape recovery. The main objective of this thesis is to know the current situation of abandoned metal mines and propose an action model for the rehabilitation and integration of abandoned mining areas of the Community of Madrid, whose advantage also is its possible extrapolation to other management areas with similar problems. From a selection of fifty-seven abandoned metal mines, a diagnosis has been made, based on safety (risk), cultural, archaeological and historical interests and how it can be related to protected areas, resulting that all but three of them need measures of protection, restoration and integration to the environment. The set of mines that are classified as a high security risk are twenty-three, and it has been made on them an Cluster Analysis, as in addition to the management formulated criteria, such as safety, protection of mining and industrial heritage and eco-landscape integration, it has been incorporated other modifying variables, such as distance to populations, roads, tracks and livestock paths, and accessibility. With the results of this analysis, a classification of similar groups of mines in relation with the intrinsic characteristics of the preselected mines and typology problems, and from it a set of viable solutions will be specified, being then drafted on a series of proposals. One of the main contributions of this research is that it consists of an inventorycharacterization- action model, which can be extrapolated to other similar environments with similar problems. The action measures that are contained in the proposals are defined as applicable to similar situations. The thesis also incorporates a geo-referenced database that allows finding the location of abandoned mines, thus giving quick access to its features and its corresponding restoration proposal.

Estudio acústico del estadio "La Peineta" utilizando line arrays

El proyecto fin de carrera consiste en un estudio acústico del Estadio de la Peineta (estadio de fútbol perteneciente al club Atlético de Madrid el cual se encuentra en construcción). Se realizará el diseño por completo de una maqueta del estadio utilizando el programa EASE. Esta maqueta se hará a escala real, exactamente como se está construyendo el estadio. A dicha maqueta se le incorporarán los diferentes materiales absorbentes específicos a cada una de las superficies que compongan el estadio. Se crearán tantas zonas de audiencia como superficies se obtenga en cada grada sobre donde se realizarán dos estudios acústicos diferentes. El primer estudio se realizará con un total de 24 clústeres de altavoces los cuales están compuestos por 10 altavoces Aero 50. La colocación estratégica de cada uno de estos altavoces se estudiará con la herramienta EASE Focus 2. Una vez obtenidas las posiciones se importarán cada uno de estos clústeres de altavoces su respectiva configuración. El otro estudio se realizará con la mitad de arrays de altavoces con la intención de tener una comparativa de recubrimiento entre un estudio y otro. Las pruebas de simulación serán analizando el nivel de presión sonora que provoca cada uno de estos estudios cuando tienen sus altavoces en funcionamiento. Se utilizará el módulo de “Area mapping” para estudiar el mapeo en cada una de las zonas de audiencia definidas, así como cada una de las distribuciones por área que predominan. Se irán anotando cada uno de los problemas e ideas que van surgiendo a lo largo de dicho proyecto para proponer una continuación y mejora del mismo. Se planteará una serie de pasos e pruebas al final de la memoria ya que se trata de un proyecto sin cerrar y puede ser continuado por otra persona. ABSTRACT. The final project is an acoustic studio Peineta Stadium (soccer stadium belongs to the club Atletico Madrid which is under construction). The design is made entirely of a model of the stadium using the EASE program. This model will be full scale, exactly as is building the stadium. A model that should be incorporated into the various specific absorbent material to each of the surfaces that make up the stadium. Hearing so many areas as surfaces is obtained in each tier on which two different acoustic studies will be conducted will be created. The first study was conducted with a total of 24 speaker clusters which are composed of 10 speakers Aero 50. The strategic placement of each of these speakers will be studied with the EASE Focus 2. Once obtained tool positions are imported each these clusters of the respective speaker configuration. The other study was conducted with half speaker arrays with the intention of having a comparative study between a coating and another. Simulation tests will be analyzing the sound pressure level which causes each of these studies have their speakers when in operation. Module "mapping area" will be used to study the mapping in each of the areas defined audience, and each of the area distributions predominate. They will be written down each of the issues and ideas that arise throughout the project to propose a continuation and improvement. a series of steps and tests at the end of the memory will be raised because it is a project without closing and may be continued for another person.

Kids and drugs : a youth leaders' handbook.

Mode of access: Internet.

Application of central composite rotatable design to modelling the effect of some operating variables on the performance of the three-product cyclone

The central composite rotatable design (CCRD) was used to design an experimental program to model the effects of inlet pressure, feed density, and length and diameter of the inner vortex finder on the operational performance of a 150-min three-product cyclone. The ranges of values of the variables used in the design were: inlet pressure: 80-130 kPa, feed density: 30 60%; length of IVF below the OVF: 50-585 mm; diameter of IVF: 35-50 mm. A total of 30 tests were conducted, which is 51 less; an that required for a three-level full factorial design. Because the model allows confident performance prediction by interpolation over the range of data in the database, it was used to construct response surface graphs to describe the effects of the variables on the performance of the three-product cyclone. To obtain a simple and yet a realistic model, it was refitted using only the variable terms that are significant at greater than or equal to 90% confidence level. Considering the selected operating variables, the resultant model is significant and predicts the experimental data well. (c) 2005 Elsevier B.V. All rights reserved.

Agriculture, Environmental Incentive Payments, and Water Quality in the Chesapeake Bay

Nonpoint sources (NPS) pollution from agriculture is the leading source of water quality impairment in U.S. rivers and streams, and a major contributor to lakes, wetlands, estuaries and coastal waters (U.S. EPA 2016). Using data from a survey of farmers in Maryland, this dissertation examines the effects of a cost sharing policy designed to encourage adoption of conservation practices that reduce NPS pollution in the Chesapeake Bay watershed. This watershed is the site of the largest Total Maximum Daily Load (TMDL) implemented to date, making it an important setting in the U.S. for water quality policy. I study two main questions related to the reduction of NPS pollution from agriculture. First, I examine the issue of additionality of cost sharing payments by estimating the direct effect of cover crop cost sharing on the acres of cover crops, and the indirect effect of cover crop cost sharing on the acres of two other practices: conservation tillage and contour/strip cropping. A two-stage simultaneous equation approach is used to correct for voluntary self-selection into cost sharing programs and account for substitution effects among conservation practices. Quasi-random Halton sequences are employed to solve the system of equations for conservation practice acreage and to minimize the computational burden involved. By considering patterns of agronomic complementarity or substitution among conservation practices (Blum et al., 1997; USDA SARE, 2012), this analysis estimates water quality impacts of the crowding-in or crowding-out of private investment in conservation due to public incentive payments. Second, I connect the econometric behavioral results with model parameters from the EPA’s Chesapeake Bay Program to conduct a policy simulation on water quality effects. I expand the econometric model to also consider the potential loss of vegetative cover due to cropland incentive payments, or slippage (Lichtenberg and Smith-Ramirez, 2011). Econometric results are linked with the Chesapeake Bay Program watershed model to estimate the change in abatement levels and costs for nitrogen, phosphorus and sediment under various behavioral scenarios. Finally, I use inverse sampling weights to derive statewide abatement quantities and costs for each of these pollutants, comparing these with TMDL targets for agriculture in Maryland.