2,111 research outputs found
Integrated control of invasive alien plants in terrestrial ecosystems
Effective management of invading alien plants in natural and semi-natural systems is imperative if we are to prevent enormous impacts. An integrated approach involving the combined use of a range of methods is usually necessary to control invasive alien plants effectively. The various methods that are available are usually classified as: mechanical methods (felling, removing of invading alien plants, often in conjunction with burning); chemical methods (using environmentally safe herbicides); and biological control (using species-specific insects and diseases from the alien plant's country of origin). Approaches available for integrated control depend on the species under consideration (features of individual species and the number and identity of species that occur together), features of the invaded systems, the availability of resources and other factors. Mechanical and chemical control are short-term activities, whereas rigorous and disciplined follow-up and rehabilitation are necessary in the medium term. Biological control can provide effective control in the short and medium term in some cases, and it is often the only really sustainable solution in the longer term. We suggest that the biological attributes of plants represent a stable set of attributes, which enable managers to devise control approaches, but that such approaches are likely to be upset by stochastic events such as fires, floods or budget cuts. While an approach of adaptive management, based on trial, error and continual improvement is a logical way in which to progress, the advent of powerful computer simulation modelling technologies will allow managers to do hundreds of 'trial and error' runs in order to explore the consequences of certain courses of action. This should represent an improvement on the current state of affairs, and should allow for better decision-making. We present a series of simulations to illustrate this point.Resource /Energy Economics and Policy,
Clientelismo, procesos electorales y cargos públicos Quibdó 2007 - 2011
El atraso de territorios como Chocó, exige de un mayor cuidado de sus gobernantes, para brindar una atención adecuada a la población -- Además requiere de la eliminación de prácticas que contribuyen a afectar los derechos de las persona -- La administración pública debe esforzarse por invertir la mayor cantidad de recursos, direccionados de la mejor manera y mantener la seguridad y el orden adelantando políticas públicas que intervengan la problemática, para permitir el imaginario de una democracia justa, que dé importancia a la vida plen
Morbidity after neck dissection in head and neck cancer patients:a study describing shoulder and neck complaints, and quality of life
Morbidity after neck dissection in head and neck cancer patients:a study describing shoulder and neck complaints, and quality of life
A\u27idah.
The comedy A’idah develops around four main characters: A’idah Mahmoudy, a Palestinian exchange student. Ahamed Mahmoudy, her father, proprietor of a souvenir shop in Bethlehem. Irma Weston, a career-politician running for congress, and Dr. Olaf Weston, a physics professor
Morbidity after neck dissection in head and neck cancer patients:a study describing shoulder and neck complaints, and quality of life
Diseño de un Sistema Automatizado de fumigación, incubación y lavados de excretas para la Granja Avícola el Esfuerzo(Masatepe)
En el presente trabajo se planteó la forma de cómo se puede llevar acabo el control del sistema automatizado de fumigación, incubación y lavado de excretas en la granja avícola el Esfuerzo. El cual cuenta con sensores, fumigadoras, ventiladores, bomba de agua y generador de aire caliente, mismo que tiene que funcionar de manera independiente un proceso del otro. Esta propuesta de automatización se lleva acabo con la ayuda de los electro niveles para el sistema de lavado de excretas los cuales mandan una señal al PLC y de acuerdo a la programación que se realizó esta determina si la bomba tiene que realizar o no la operación de lavado.
Para poder realizar la programación, fue necesario acudir a las instalaciones y realizar un estudio de tiempo para los procesos que se pretenden automatizar y de esta manera ver la forma que funciona actualmente, así como determinar las fallas existentes para después proponer las mejoras que se pueden implementar.
Después de que se determinó la forma correcta del proceso para sistema de incubación para pollos de crianza, a través de un sensor de temperatura y del PLC se procedió a realizar el diagrama de programación (FUP) en bloque para el autómata programable LOGO! 230RC de siemens, diagramas de instalación y esquemas eléctricos para el sistema automatizado dentro de la granja.
Durante el desarrollo de este proyecto se observó que la automatización trae grandes beneficios (tiempos exactos, no hay perdidas, mayor eficiencia en el servicio y lo más importante reducen los costos de mano de obra hasta un 50% en este caso) y una alta calidad de producción, que es el objetivo principal del sistema automatizado para la granj
Invasive alien plants in South Africa: How well do we understand the ecological impacts?
This paper examines the evidence for the effects of invasive alien plants in natural and semi-natural ecosystems in South Africa. Invasive alien plants are concentrated in the Western Cape, along the eastern seaboard, and into the eastern interior, but there is a shortage of accurate data on abundance within this range. Most information on site-specific impacts comes from the fynbos biome, and is generally poor for other biomes. The consequences of invasions for the delivery of ecosystem goods and services to people are, with the notable exception of their influence on water resources, inadequately studied. Our understanding of many of the broader aspects of invasion ecology needs to be enhanced, and we identify important challenges for research to address critical gaps in knowledge. Priorities for future research include the development of a predictive understanding of the rates of spread of invasive alien plants, and the development of achievable goals for ecosystem repair after clearing, including measurable criteria for assessing the success of restoration. Climate change could significantly exacerbate problems with invasive species and work is needed to accommodate plausible trajectories in planning and management frameworks. Perhaps the greatest challenge for South African ecologists is to address the twin issues of skills development and social transformation, to ensure that adequate and relevant ecological expertise is maintained to meet future research and management needs. Formal collaboration between organizations to address capacity building and educational transformation in the field of invasion ecology would represent a significant step forward
Best evidence rehabilitation for chronic pain, part 3 : low back pain
Chronic Low Back Pain (CLBP) is a major and highly prevalent health problem. Given the high number of papers available, clinicians might be overwhelmed by the evidence on CLBP management. Taking into account the scale and costs of CLBP, it is imperative that healthcare professionals have access to up-to-date, evidence-based information to assist them in treatment decision-making. Therefore, this paper provides a state-of-the-art overview of the best evidence non-invasive rehabilitation for CLBP. Taking together up-to-date evidence from systematic reviews, meta-analysis and available treatment guidelines, most physically inactive therapies should not be considered for CLBP management, except for pain neuroscience education and spinal manipulative therapy if combined with exercise therapy, with or without psychological therapy. Regarding active therapy, back schools, sensory discrimination training, proprioceptive exercises, and sling exercises should not be considered due to low-quality and/or conflicting evidence. Exercise interventions on the other hand are recommended, but while all exercise modalities appear effective compared to minimal/passive/conservative/no intervention, there is no evidence that some specific types of exercises are superior to others. Therefore, we recommend choosing exercises in line with the patient's preferences and abilities. When exercise interventions are combined with a psychological component, effects are better and maintain longer over time
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