Alley cropping of willows and grassland for bioenergy provision: productivity, tree-crop interactions and energy balance

The demand for biomass for bioenergy has increased rapidly in industrialized countries in the recent years. Biogenic energy carriers are known to reduce CO2 emissions. However, the resource-inefficient production of biomass often caused negative impacts on the environment, e.g. biodiversity losses, nitrate leaching, and erosion. The detrimental effects evolved mainly from annual crops. Therefore, the aim of modern bioenergy cropping systems is to combine yield stability and environmental benefits by the establishment of mixed-cropping systems. A particular emphasis is on perennial crops which are perceived as environmentally superior to annual crops. Agroforestry systems represent such mixed perennial cropping systems and consist of a mix of trees and arable crops or grassland within the same area of land. Agroforestry practices vary across the globe and alley cropping is a type of agroforestry system which is well adapted to the temperate zone, with a high degree of mechanization. Trees are planted in rows and crops are planted in the alleyways, which facilitates their management by machinery. This study was conducted to examine a young alley cropping system of willows and two grassland mixtures for bioenergy provision under temperate climate conditions. The first part of the thesis identified possible competition effects between willows and the two grassland mixtures. Since light seemed to be the factor most affecting the yield performance of the understory in temperate agroforestry systems, a biennial in situ artificial shade experiment was established over a separate clover-grass stand to quantify the effects of shade. Data to possible below- and aboveground interactions among willows and the two grassland mixtures and their effects on productivity, sward composition, and quality were monitored along a tree-grassland interface within the alleys. In the second part, productivity of the alley cropping system was examined on a triennial time frame and compared to separate grassland and willow stands as controls. Three different conversion technologies (combustion of hay, integrated generation of solid fuel and biogas from biomass, whole crop digestion) were applied to grassland biomass as feedstock and analyzed for its energetic potential. The energetic potential of willow wood chips was calculated by applying combustion as conversion technique. Net energy balances of separate grassland stands, agroforestry and pure willow stands evaluated their energy efficiency. Results of the biennial artificial shade experiment showed that severe shade (80 % light reduction) halved grassland productivity on average compared to a non-shaded control. White clover as heliophilous plant responded sensitively to limited radiation and its dry matter contribution in the sward decreased with increasing shade, whereas non-leguminous forbs (mainly segetal species) benefited. Changes in nutritive quality could not be confirmed by this experiment. Through the study on interactions within the alleys of the young agroforestry system it was possible to outline changes of incident light, soil temperature and sward composition of clover-grass along the tree-grassland interface. Nearly no effects of trees on precipitation, soil moisture and understory productivity occurred along the interface during the biennial experiment. Considering the results of the productivity and the net energy yield alley cropping system had lower than pure grassland stands, irrespective of the grassland seed mixture or fertilization, but was higher than that for pure willow stands. The comparison of three different energetic conversion techniques for the grassland biomass showed highest net energy yields for hay combustion, whereas the integrated generation of solid fuel and biogas from biomass (IFBB) and whole crop digestion performed similarly. However, due to the low fuel quality of hay, its direct combustion cannot be recommended as a viable conversion technique, whereas IFBB fuels were of a similar quality to wood chip from willow.

Balance de las operaciones de interdicción aérea contra el narcotráfico entre Brasil y Colombia durante la administración Uribe I

El problema del tráfico de estupefacientes se ha convertido no solo en un dificultad para los países productores y consumidores, sino también para países de paso que a su vez se convierten en consumidores. Así la frontera entre Brasil y Colombia se ha convertido en objetivo para la lucha contra las drogas, usando herramientas como la interdicción aérea.

Análisis de los alcances y las limitaciones de la implementación del Principio de Responsabilidad Compartida en el marco del Problema Mundial de las Drogas. Un balance de su aplicabilidad en el Continente Americano (1998-2010).

El texto hace una evaluación parcial de la implementación del Principio de Responsabilidad Compartida en el Continente Americano durante el período 1998-2010; para ello se tiene en cuenta tres principales mecanismos de la región, su implementación, sus buenos resultados y sus limitaciones en la lucha contra las drogas ilícitas.

Métodos de planificación, evaluación y control de los proyectos de Ingeniería.

Esta obra consta de trece capítulos a lo largo de los cuales se describe al detalle el proceso de planificación, evaluación y control en proyectos de ingeniería, para lo cual todos han de precisar: a) Las características especiales de cada caso. b) El ámbito espacial en el que se desarrolla. c) La complejidad y duración. d) La experiencia en proyectos similares y conocimientos de los mismos. Los contenidos de los capítulos son, los siguientes: 1. Estudios de planificación y programación. 2. Actuaciones previas a la concesión del proyecto. 3. Gráfica de barras. 4. Métodos del camino crítico y P.E.R.T. 5. Aplicaciones prácticas de los métodos de planificación. 6. Técnica de la Línea de Balance (LOB). 7. Programación lineal. 8. Teoría de colas. 9. Modelos de inventarios. Demanda Determinista. 10. Análisis económico básico. 11. Análisis financiero de proyectos. 12. Evaluación económico financiera de inversiones. 13. Decisiones técnico-económicas. Aplicaciones en la ingeniería de la construcción. Ejemplos resueltos.

Hacia la construcción del trabajo en red para una universidad saludable. Balance del “I Foro internacional sobre experiencias en universidad saludable”

Esta compilación busca favorecer el trabajo en red de las instituciones universitarias que promueven la actividad física como elemento esencial de la salud de su comunidad. También se orienta a socializar los resultados del I Foro Internacional de experiencias en universidad saludable, como avance del trabajo interinstitucional que se promovió durante el evento, con aportes de expertos internacionales, nacionales y las experiencias de las universidades. Este material, va dirigido a todas las Instituciones Universitarias y a sus grupos de investigación en el tema de la actividad física, así como a Universidades de América Latina interesadas en la estrategia de universidad saludable y a la población universitaria en general.Este material, va dirigido a todas las Instituciones Universitarias y a sus grupos de investigación en el tema de la actividad física, así como a Universidades de América Latina interesadas en la estrategia de universidad saludable y a la población universitaria en general.

La cooperación hacia Mauritania y la externalización del control migratorio español como mecanismos de securitización de la política migratoria española hacia Mauritania (1996 - 2013)

La llegada masiva de migrantes irregulares provenientes del África sub-sahariana ha sido un fenómeno que ha afectado en términos económicos, sociales, políticos y culturales, a los países que conforman la Unión Europea. Es así como los países más afectados por este tipo de migración (España, Grecia e Italia) han pedido a los demás miembros de la Unión adoptar una política conjunta y armonizada con el fin de solucionar la problemática migratoria irregular. No obstante, la cooperación, como acción unilateral, ha resultado ser el mecanismo más efectivo, en especial el caso español, para contener y externalizar los controles del movimiento migratorio irregular subsahariano en países como Mauritania, como resultado de un proceso de securitización de la migración irregular al interior de España a comienzos del siglo XX.

Psicomotricidad en el deficiente mental : balance psicomotor H. Bucher.

Estudiar el tipo de transtornos que en los niños deficientes ha contribuido a reducir sus capacidades básicas. 4 sujetos. Balance psicomotor H. Bucher. La motricidad está en el origen de todo conocimiento ya en la primera infancia, por ello es conveniente, en un primer momento, potenciar este aspecto con diversos ejercicios: ritmo, gimnasia, expresión corporal, muy útiles en los parvularios y en edades preescolares. El movimiento es la esencia de la función motora y resulta de la actividad muscular. En la base de la psicomotricidad lo motor y lo afectivo constituyen toda una relación y expresión psicofísica. Los disturbios afectivos psicomotores se refuerzan si en dicha relación se produce un desequilibrio. Por ello, es muy conveniente un ambiente favorable, buenas condiciones educativas y afectivas, circustancias fundamentales para un buen desarrollo progresivo en psicomotricidad. Hay que diferenciar entre motricidad: como acto de moverse y psicomotricidad: como movimiento intencionado. La tonicidad sigue una evolución: en un principio el niño muy pequeño tiene manifestaciones tónicas, sobre las que no ejerce ningún control y le envuelven por completo: al ir progresando en diversos planos consigue dominar dichas manifestaciones. El diálogo es fundamental en todo tipo de educación, y en la educación especial conviene llegar a este dialogo desde varias perspectivas: corporal, comunicativa y comprensiva. En cuanto a los métodos que se aplican, generalmente, al estudio del deficiente, es totalmente seguro que aquellos cuyo objetivo es la simple baremación del cociente intelectual no llegarán a prácticos, ni a completos resultados, en cambio se consideran más interesantes aquellos cuyo estadio comprende otras facetas como por ejemplo, la observación, que va más allá del estudio merámente intelectual. El terapéuta en psicomotricidad ha de penetrar en lo vivenciado por el sujeto, consiguiendo de este modo su autonomía y equilibrio. La originalidad de toda terapía psicomotricidad está en introducir el estudio de toda dimensión corporal.

A regime-dependent balanced control variable based on potential vorticity

In this paper it is argued that rotational wind is not the best choice of leading control variable for variational data assimilation, and an alternative is suggested and tested. A rotational wind parameter is used in most global variational assimilation systems as a pragmatic way of approximately representing the balanced component of the assimilation increments. In effect, rotational wind is treated as a proxy for potential vorticity, but one that it is potentially not a good choice in flow regimes characterised by small Burger number. This paper reports on an alternative set of control variables which are based around potential vorticity. This gives rise to a new formulation of the background error covariances for the Met Office's variational assimilation system, which leads to flow dependency. It uses similar balance relationships to traditional schemes, but recognises the existence of unbalanced rotational wind which is used with a new anti-balance relationship. The new scheme is described and its performance is evaluated and compared to a traditional scheme using a sample of diagnostics.

Long-term change, interannual and intra-seasonal variability in climate and glacier mass balance in the Central Greater Caucasus, Russia

Long-term trends, interannual and intra-seasonal variability in the mass-balance record from Djankuat glacier, central Greater Caucasus, Russia, are related to local climate change, synoptic and large-scale anomalies in atmospheric circulation. A clear warming signal emerged in the central Greater Caucasus in the early 1990s, leading to a strong increase in ablation. In the absence of a compensating change in winter accumulation, the net mass balance of Djankuat has declined. The highest value of seasonal ablation on record was registered in the summer of 2000. At the beginning of the 21st century these trends reversed. Ablation was below average even in the summer of 2003, which was unusually warm in western Europe. Precipitation and winter accumulation were high, allowing for a partial recovery of net mass balance. The interannual variability in the components of mass balance is weakly related to the North Atlantic Oscillation (NAO) and the Scandinavian teleconnection patterns, but there is a clear link with the large-scale circulation anomalies represented by the Rossby pattern. Five synoptic categories have been identified for the ablation season of 2005, revealing a strong separation between components of radiation budget, air temperature and daily melt. Air temperature is the main control over melt. The highest values of daily ablation are related to the strongly positive NAO which forces high net radiation, and to the warm and moist advection from the Black Sea.

Control of human immunodeficiency virus type-1 protease activity in insect cells expressing Gag-Pol rescues assembly of immature but not mature virus-like particles

Expression of human immunodeficiency virus type 1 (HIV-1) Gag protein in insect cells using baculovirus vectors leads to the abundant production of virus-like particles (VLPs) that represent the immature form of the virus. When Gag-Pol is included, however, VLP production is abolished, a result attributed to premature protease activation degrading the intracellular pool of Gag precursor before particle assembly can occur. As large-scale synthesis of mature noninfectious VLPs would be useful, we have sought to control HIV protease activity in insect cells to give a balance of Gag and Gag-Pol that is compatible with mature particle formation. We show here that intermediate levels of protease activity in insect cells can be attained through site-directed mutagenesis of the protease and through antiprotease drug treatment. However, despite Gag cleavage patterns that mimicked those seen in mammalian cells, VLP synthesis exhibited an essentially all-or-none response in which VLP synthesis occurred but was immature or failed completely. Our data are consistent with a requirement for specific cellular factors in addition to the correct ratio of Gag and Gag-Pol for assembly of mature retrovirus particles in heterologous cell types. (C) 2003 Elsevier Science (USA). All rights reserved.

Disruption of sitting balance after stroke: influence of spoken output

Objectives: To identify the extent of dual task interference between cognitive and motor tasks, (cognitive motor interference (CMI)) in sitting balance during recovery from stroke; to compare CMI in sitting balance between stroke and non-stroke groups; and to record any changes to CMI during sitting that correlate with functional recovery. Method: 36 patients from stroke rehabilitation settings in three NHS trusts. Healthy control group: 21 older volunteers. Measures of seated postural sway were taken in unsupported sitting positions, alone, or concurrently with either a repetitive utterance task or an oral word category generation task. Outcome measures were variability of sway area, path length of sway, and the number of valid words generated. Results: Stroke patients were generally less stable than controls during unsupported sitting tasks. They showed greater sway during repetitive speech compared with quiet sitting, but did not show increased instability to posture between repetitive speech and word category generation. When compared with controls, stroke patients experienced greater dual task interferences during repetitive utterance but not during word generation. Sway during repetitive speech was negatively correlated with concurrent function on the Barthel ADL index. Conclusions: The stroke patients showed postural instability and poor word generation skills. The results of this study show that the effort of verbal utterances alone was sufficient to disturb postural control early after stroke, and the extent of this instability correlated with concomitant Barthel ADL function.

Preliminary results from a real time control system using optical information

Successful results from training an adaptive controller to use optical information to balance an inverted pendulum are presented in comparison to the training requirements using traditional controller inputs. Results from research into the psychology of the sense of balance in humans are presented as the motivation for the investigation of this new type of controller. The simulated model of the inverted pendulum and the virtual reality environments used to provide the optical input are described The successful introduction of optical information is found to require the preservation of at least two of the traditional input types and entail increased training time for the adaptive controller and reduced performance (measured as the time the pendulum remains upright).

Results of applying sensor fusion to a control system using optic flow

The results from applying a sensor fusion process to an adaptive controller used to balance all inverted pendulum axe presented. The goal of the sensor fusion process was to replace some of the four mechanical measurements, which are known to be sufficient inputs for a linear state feedback controller to balance the system, with optic flow variables. Results from research into the psychology of the sense of balance in humans were the motivation for the investigation of this new type of controller input. The simulated model of the inverted pendulum and the virtual reality environments used to provide the optical input are described. The successful introduction of optical information is found to require the preservation of at least two of the traditional input types and entail increased training till-le for the adaptive controller and reduced performance (measured as the time the pendulum remains upright)

Investigation into the performance of an algorithm for deriving concise descriptions of optic flow fields for real-time control

This paper describes a region-based algorithm for deriving a concise description of a first order optical flow field. The algorithm described achieves performance improvements over existing algorithms without compromising the accuracy of the flow field values calculated. These improvements are brought about by not computing the entire flow field between two consecutive images, but by considering only the flow vectors of a selected subset of the images. The algorithm is presented in the context of a project to balance a bipedal robot using visual information.

Typical control curricula and using software for teaching/assessment: a UK perspective

This paper describes some of the preliminary outcomes of a UK project looking at control education. The focus is on two aspects: (i) the most important control concepts and theories for students doing just one or two courses and (ii) the effective use of software to improve student learning and engagement. There is also some discussion of the correct balance between teaching theory and practise. The paper gives examples from numerous UK universities and some industrial comment.