Agricultural practices and horizontal nutrient balances in urban gardens and the alternative use of urban agricultural land in Khartoum, Sudan

The surge in the urban population evident in most developing countries is a worldwide phenomenon, and often the result of drought, conflicts, poverty and the lack of education opportunities. In parallel with the growth of the cities is the growing need for food which leads to the burgeoning expansion of urban and peri-urban agriculture (UPA). In this context, urban agriculture (UA) contributes significantly to supplying local markets with both vegetable and animal produce. As an income generating activity, UA also contributes to the livelihoods of poor urban dwellers. In order to evaluate the nutrient status of urban soils in relation to garden management, this study assessed nutrient fluxes (inputs and outputs) in gardens on urban Gerif soils on the banks of the River Nile in Khartoum, the capital city of Sudan. To achieve this objective, a preliminary baseline survey was carried out to describe the structure of the existing garden systems. In cooperation with the author of another PhD thesis (Ms. Ishtiag Abdalla), alternative uses of cow dung in brick making kilns in urban Khartoum were assessed; and the socio-economic criteria of the brick kiln owners or agents, economical and plant nutritional value of animal dung and the gaseous emission related to brick making activities were assessed. A total of 40 household heads were interviewed using a semi-structured questionnaire to collect information on demographic, socio-economic and migratory characteristics of the household members, the gardening systems used and the problems encountered in urban gardening. Based on the results of this survey, gardens were divided into three groups: mixed vegetable-fodder gardens, mixed vegetable-subsistence livestock gardens and pure vegetable gardens. The results revealed that UA is the exclusive domain of men, 80% of them non-native to Khartoum. The harvested produce in all gardens was market oriented and represented the main source of income for 83% of the gardeners. Fast growing leafy vegetables such as Jew’s mallow (Corchorous olitorius L.), purslane (Portulaca oleracea L.) and rocket (Eruca sativa Mill.) were the dominant cultivated species. Most of the gardens (95%) were continuously cultivated throughout the year without any fallow period, unless they were flooded. Gardeners were not generally aware of the importance of crop diversity, which may help them overcome the strongly fluctuating market prices for their produce and thereby strengthen the contributions of UA to the overall productivity of the city. To measure nutrient fluxes, four gardens were selected and their nutrients inputs and outputs flows were monitored. In each garden, all plots were monitored for quantification of nutrient inputs and outputs. To determine soil chemical fertility parameters in each of the studied gardens, soil samples were taken from three selected plots at the beginning of the study in October 2007 (gardens L1, L2 and H1) and in April 2008 (garden H2) and at the end of the study period in March 2010. Additional soil sampling occurred in May 2009 to assess changes in the soil nutrient status after the River Nile flood of 2008 had receded. Samples of rain and irrigation water (river and well-water) were analyzed for nitrogen (N), phosphorus (P), potassium (K) and carbon (C) content to determine their nutrient inputs. Catchment traps were installed to quantify the sediment yield from the River Nile flood. To quantify the nutrient inputs of sediments, samples were analyzed for N, P, K and organic carbon (Corg) content, cation exchange capacity (CEC) and the particle size distribution. The total nutrient inputs were calculated by multiplying the sediment nutrient content by total sediment deposits on individual gardens. Nutrient output in the form of harvested yield was quantified at harvest of each crop. Plant samples from each field were dried, and analyzed for their N, P, K and Corg content. Cumulative leaching losses of mineral N and P were estimated in a single plot in garden L1 from December 1st 2008 to July 1st 2009 using 12 ion exchange resins cartridges. Nutrients were extracted and analyzed for nitrate (NO3--N), ammonium (NH4+-N) and phosphate PO4-3-P. Changes in soil nutrient balance were assessed as inputs minus outputs. The results showed that across gardens, soil N and P concentrations increased from 2007 to 2009, while particle size distribution remained unchanged. Sediment loads and their respective contents of N, P and Corg decreased significantly (P < 0.05) from the gardens of the downstream lowlands (L1 and L2) to the gardens of the upstream highlands (H1 and H2). No significant difference was found in K deposits. None of the gardens received organic fertilizers and the only mineral fertilizer applied was urea (46-0-0). This equaled 29, 30, 54, and 67% of total N inputs to gardens L1, L2, H1, and H2, respectively. Sediment deposits of the River Nile floods contributed on average 67, 94, 6 and 42% to the total N, P, K and C inputs in lowland gardens and 33, 86, 4 and 37% of total N, P, K and C inputs in highland gardens. Irrigation water and rainfall contributed substantially to K inputs representing 96, 92, 94 and 96% of total K influxes in garden L1, L2, H1 and H2, respectively. Following the same order, total annual DM yields in the gardens were 26, 18, 16 and 1.8 t ha-1. Annual leaching losses were estimated to be 0.02 kg NH4+-N ha-1 (SE = 0.004), 0.03 kg NO3--N ha-1 (SE = 0.002) and 0.005 kg PO4-3-P ha-1 (SE = 0.0007). Differences between nutrient inputs and outputs indicated negative nutrient balances for P and K and positive balances of N and C for all gardens. The negative balances in P and K call for adoptions of new agricultural techniques such as regular manure additions or mulching which may enhance the soil organic matter status. A quantification of fluxes not measured in our study such as N2-fixation, dry deposition and gaseous emissions of C and N would be necessary to comprehensively assess the sustainability of these intensive gardening systems. The second part of the survey dealt with the brick making kilns. A total of 50 brick kiln owners/or agents were interviewed from July to August 2009, using a semi-structured questionnaire. The data collected included general information such as age, family size, education, land ownership, number of kilns managed and/or owned, number of months that kilns were in operation, quantity of inputs (cow dung and fuel wood) used, prices of inputs and products across the production season. Information related to the share value of the land on which the kilns were built and annual income for urban farmers and annual returns from dung for the animal raisers was also collected. Using descriptive statistics, budget calculation and Gini coefficient, the results indicated that renting the land to brick making kilns yields a 5-fold higher return than the rent for agriculture. Gini coefficient showed that the kiln owners had a more equal income distribution compared to farmers. To estimate emission of greenhouse gases (GHGs) and losses of N, P, K, Corg and DM from cow dung when used in brick making, samples of cow dung (loose and compacted) were collected from different kilns and analyzed for their N, P, K and Corg content. The procedure modified by the Intergovernmental Panel on Climate Change (IPCC, 1994) was used to estimate the gaseous emissions of cow dung and fuel wood. The amount of deforested wood was estimated according to the default values for wood density given by Dixon et al. (1991) and the expansion ratio for branches and small trees given by Brown et al. (1989). The data showed the monetary value of added N and P from cow dung was lower than for mineral fertilizers. Annual consumption of compacted dung (381 t DM) as biomass fuel by far exceeded the consumption of fuel wood (36 t DM). Gaseous emissions from cow dung and fuel wood were dominated by CO2, CO and CH4. Considering that Gerif land in urban Khartoum supports a multifunctional land use system, efficient use of natural resources (forest, dung, land and water) will enhance the sustainability of the UA and brick making activities. Adoption of new kilns with higher energy efficiency will reduce the amount of biomass fuels (cow dung and wood) used the amount of GHGs emitted and the threat to the few remaining forests.

Structural insights into the allosteric activation mechanism of cGMP-dependent protein kinase I

Cyclic GMP-dependent protein kinase (PKG) is a key transducer in the NO-cGMP signaling pathway. In this line, PKG has been considered an important drug target for treating hypertensive cardiovascular and pulmonary diseases. However, the investigation of PKG’s allosteric activation mechanism has been hampered by a lack of structural information. One of the fundamental questions on the cGMP-dependent activation of PKG is how the enzyme can distinguish cGMP over cAMP and selectively respond to cGMP. To ensure proper signaling, PKG must have developed unique features to ensure its activation upon the right activation signal. In this thesis, the cGMP-selective activation mechanism of PKG was studied through determining crystal structures of three truncated constructs of the regulatory domain [CNB-A (92-227), CNB-B (271-369), and CNB-A/B (92-351)] of PKG Iβ in the absence or presence of cyclic nucleotides. Herein, two individual CNB domain structures with biochemical data revealed that the C-terminal CNB domain (CNB-B) is responsible for cGMP selectivity, while the N-terminal CNB-domain (CNB-A) has a higher binding affinity for both cGMP and cAMP without showing any selectivity. Based on these crystal structures, mutagenesis studies were performed in which the critical residues for cyclic nucleotide selectivity and activation were identified. Furthermore, we discovered that the conformational changes of the C-terminal helix of the CNB-B that bridges between the regulatory and catalytic domains including the hydrophobic capping interaction are crucial for PKG activation. In addition, to observe the global conformation of the activated R-domain, I solved a co-crystal structure of the CNB-A/B with cGMP. Although a monomeric construct was crystallized, the structure displays a dimer. Strikingly, the CNB-A domain and its bound cGMP provide a key interface for this dimeric interaction. Using small angle X-ray scattering (SAXS), the existence of the cGMP-mediated dimeric interface within the CNB domains was confirmed. Furthermore, measuring cGMP-binding affinities (EC50) of the dimeric interface mutants as well as determining activation constants (Ka) revealed that the interface formation is important for PKG activation. To conclude, this thesis study provides a new mechanistic insight in PKG activation along with a newly found interface that can be targeted for designing PKG-specific activity modulators.

Elaboraci??n de recursos TIC para tecnolog??a

Se presenta experiencia educativa que propone la elaboraci??n de materiales TIC para el uso en el aula. Se realiza en el IES Fernando de los R??os en Fuente Vaqueros, Granada. Los objetivos son: elaborar material TIC sobre el curr??culo de ESO; crear y elaborar unidades did??cticas y actividades mediante estos recursos.

Conoce tu municipio.

Cuaderno de trabajo dirigido a los alumnos del municipio de Cartagena (Murcia). Pretende aportar un conocimiento sobre cómo se organiza un Ayuntamiento, qué servicios presta y cuáles son algunos de los Servicios Municipales existentes: Bomberos, Policia Municipal, Oficina de Turismo, etc. En el mismo cuaderno se incluye una breve historia del municipio y de las fuentes de riqueza principales. Se añaden ocho fichas de trabajo complementarias a las visitas realizadas a diferentes centros y/o servicios del municipio.

Fundamentos pedagógicos de la Ley Orgánica de la Participación, la Evaluación y el Gobierno de los Centros Docentes.

El libro recoge los textos íntegros de la Ley Orgánica de la Participación, la Evaluación y el Gobierno de los Centros Docentes (1996), así como el de la Ley Orgánica de Ordenación General del Sistema Educativo (1990), con una introducción en la que se hace referencia a los conceptos-clave contenidos en las leyes: calidad, participación, formación del profesorado, evaluación, etc., así como comentarios separados y específicos sobre inspección, investigación y evaluación del sistema y de los procesos educativos.

El marco legal del sistema educativo.

El autor es profesor de Formación Empresarial del Instituto Politécnico de FP de Cartagena

Investigación evaluativa del actual sistema de enseñanza en Bachillerato y posibles alternativas experimentales.

Valorar el grado de eficiencia del actual sistema de enseñanza en Bachillerato y dar a conocer los resultados de una evaluación realizada en un Instituto concreto. 1517 alumnos/as de primero y segundo de BUP y COU del Instituto de Bachillerato Menéndez Pidal de Avilés seleccionados al azar entre los cursos académicos 1983-1987. Muestra secundaria de 2559 sujetos de 7 centros distintos de Medias ubicados en otras tantas localidades de Asturias. Plantea 5 diseños experimentales: análisis de aptitudes y rendimiento y su correlación; investigaciones transversales para analizar la posible relación entre status socio-económico y aptitudes y rendimiento; estudios longitudinales consistentes en el seguimiento de una muestra de 168 sujetos desde su ingreso en el Instituto hasta terminar COU; estudios de correlación entre rasgos de personalidad y rendimiento; análisis de intereses profesionales y adecuación entre aptitudes e intereses. Test AMPE de inteligencia y aptitudes. Test SAE de aptitud para el estudio. Cuestionario PEI de personalidad. Perfil de intereses profesionales PIP. Calificaciones escolares. Referente a la relación entre rendimiento y status social se ha confirmado que existen diferencias estadísticamente significativas, siendo en el factor verbal donde se marcan las máximas diferencias. No se ha podido comprobar una relación unívoca entre rasgos de personalidad y rendimiento académico. En los factores comprensión verbal y cálculo numérico, los actuales estudiantes ingresan en BUP con una desventaja considerable con respecto a los sujetos del Sistema Educativo anterior. Las deficiencias registradas en el factor verbal se pueden corregir a lo largo del Bachillerato, sin embargo, en cuanto a la evolución en el factor cálculo, los estudios longitudinales efectuados permiten concluir que los automatismos de ese factor han de mecanizarse en etapas tempranas de desarrollo y que, transcurrido un periodo más o menos crítico, su progresión será lenta e imprecisa. Al evaluar el rendimiento en función de la capacidad se constata una muy acusada desproporción entre el nivel de desarrollo de las aptitudes y los índices globales de aprovechamiento escolar. Los procesos de interacción del aula pueden ser una de las causas de estos desequilibrios. Propone como solución el replanteamiento de los contenidos de los currícula de Lengua y Matemáticas en una línea de vuelta a lo clásico y la revisión de los proyectos curriculares en Ciencias. Para mejorar la calidad de la interacción y de los procesos de enseñanza-aprendizaje propone la implantación de servicios de orientación.

Estudio experimental sobre programación y desarrollo de un curso de Inglés específico para estudiantes de Enfermería.

Iniciar al alumno en el conocimiento del inglés usado específicamente en Enfermería; desarrollar las cuatro destrezas básicas: hablar, leer, entender y escribir; facilitar a los alumnos el acceso a una bibliografía inglesa. Alumnos de segundo curso de Diplomatura en Enfermería, de la EU de Enfermería de Granada. El programa de la investigación se divide en dos bloques: explicaciones a través de libros de texto y utilización de artículos, a través de los cuales se analizan cuestiones de Enfermería. Se hacen evaluaciones al final de cada unidad temática. Pruebas realizadas a los alumnos, participación del alumno en clase, encuestas realizadas a la institución, a los alumnos, al profesorado y al personal administrativo. Tablas descriptivas y gráficos. El modelo de programación presentado, comprende el libro de texto y artículos científicos. No existe relación entre las unidades temáticas y los artículos, debido a la limitación de material y a la limitación de conocimientos del alumno, sobre Enfermería. Proporcionar a personas que trabajan en este campo unos datos realistas y experimentados, que pudieran ser de interés y utilidad.

Jugar a la Carta Magna : actividades sobre la Constitución Española.

Obtuvo Mención especial Antonio Domínguez Ortiz resuelto por el XVIII Concurso para el Fomento de la Investigación e Innovación Educativa

El corto publicitario : una propuesta de desarrollo curricular para las materias de Comunicación de la ESO y el Bachillerato.

Obtuvo Primer Premio Antonio Domínguez Ortiz resuelto por el XVII Concurso para el Fomento de la Investigación e Innovación Educativa

Prevalencia, sintomatolog??a y distribuci??n del trastorno negativista desafiante

Resumen tomado de la publicaci??n

El envejecimiento afecta a las pruebas de compleción de raíces y reconocimiento pero no a la generación de categorías.

Resumen tomado de la publicación

De la gestión cultural a la administración de las culturas

Este texto, a partir de la aproximación reflexiva desde la docencia, la investigación y la extensión académica, propone las claves de lectura para la comprensión de la administración cultural. Para ello, propone como campo de acción la disciplina de la administración de la cultura, como un sector de actividad económica y de configuración empresarial de trascendencia. Producto de esta reflexión, identifica la problemática de reduccionismo gerencial a la que fue sometida la disciplina administrativa durante el siglo XX, para rescatar su lógica y ethos relacional con otras disciplinas. Además, establece un concepto y un marco de trabajo para el desarrollo de la administración como disciplina, en términos de tareas académicas, para profundizar en la investigación de la administración de las culturas, la generación de saberes y didácticas. Lo anterior, con el propósito de formar capital humano preparado para enfrentar este tema estratégico de las naciones, las cuales están envueltas en dinámicas locales, basadas en disputas hegemónicas y asimétricas, de una economía simbólica con valor estratégico y, por tanto, con la necesidad de una administración de las organizaciones del trabajo cultural.

Multidimensional Adaptations for Open Learning Management Systems

Our work is focused on alleviating the workload for designers of adaptive courses on the complexity task of authoring adaptive learning designs adjusted to specific user characteristics and the user context. We propose an adaptation platform that consists in a set of intelligent agents where each agent carries out an independent adaptation task. The agents apply machine learning techniques to support the user modelling for the adaptation process