Spatial Patterns of Tree Invasion in an Old Field: Implications for Restoration

In north-eastern North America, abandoned agricultural fields typically revert to forest after many decades of spontaneous succession. This process can be influenced in part by nearby available propagule sources and their natural patterns of dispersal. Ecological restoration encompasses understanding this natural process and how it may influence active or passive restoration efforts. This study attempts to determine the spatial and temporal patterns of establishing trees arising in an old field at 10 years post-cultivation and the implications of this process on restoration at rare and other similar sites. The 0.8 ha field is situated at rare, an ecological reserve in Cambridge, Ontario and is bordered by forest or hedgerow on all sides. Using Environmental Monitoring and Assessment Network (EMAN) protocols, vegetation sampling was completed in the field and adjacent forest and hedgerow. A complete tree inventory was undertaken in the field, followed by a sampling of potential seed sources in the forest and hedgerow. ESRI ArcMap, a Geographic Information System (GIS) was utilized for both spatial representation and spatial analysis. Research revealed that the application of geostatistics to ecological data here and elsewhere in the literature has some specific challenges which need to be overcome for analysis of spatial data. Currently, the old field shows early signs of woody plant invasion from the nearby forest. Both trees and shrubs have become established, though not yet dominant. The primary dispersal of these species follows spatial patterns based on method of dispersal (wind, nut, fruit and clonal) and there is a higher degree of clustering of all species closer to the forest edge. Invasive species such as Rhamnus cathartica and Rhamnus frangula have become established in the old field and may influence successional patterns. Implications for restoration include the creation of goals and objectives which incorporate these natural processes into a future management plan. Specific recommendations include: 1) Develop a management strategy for invasive species such as Rhamnus spp. which can detrimentally affect restoration goals; 2) Continue to monitor EMAN plots for the production of time-series data on the same site; 3) Identify sites with good regeneration potential based on spatial patterns identified in this research and collect additional information such as soil conditions, canopy cover, etc.; 4) Extend the current GIS database created for this thesis to become an inventory of natural and cultural features for the reserve. Advanced spatial analysis required a more extensive data set and/or custom programming

Electron-Phonon Interaction in Tetrahedral Semiconductors

Effects of electron-phonon interactions on the band structure can be experimentally investigated in detail by measuring the temperature dependence of energy gaps or critical points (van Hove singularities) of the optical excitation spectra. These studies have been complemented in recent years by observing the dependence of such spectra on isotopic mass whenever different stable isotopes of a given atom are available at affordable prices. In crystals composed of different atoms, the effect of the vibration of each separate atom can thus be investigated by isotopic substitution. Because of the zero-point vibrations, such effects are present even at zero temperature (T = 0). In this paper we discuss state-of-the-art calculations of the dielectric function spectra and compare them with experimental results, with emphasis on the differences introduced by the electron-phonon interaction. The temperature dependence of various optical parameters will be described by means of one or two (in a few cases three) Einstein oscillators, except at the lowest temperatures where the T4 law (contrary to the Varshini T2 result) will be shown to apply. Increasing an isotopic mass increases the energy gaps, except in the case of monovalent Cu (e.g., CuCl) and possibly Ag (e.g., AgGaS2). It will be shown that the gaps of tetrahedral materials containing an element of the first row of the periodic table (C,N,O) are strongly affected by the electron-phonon interaction. It will be conjectured that this effect is related to the superconductivity recently observed in heavily boron-doped carbon.Comment: 17 pages, 17 fifure

Doctoral dissertation management at the University of Granada

La Universidad de Granada (UGR) cuenta desde 2005 con el Proyecto DIGIBUG, un modelo que mejora la visibilidad y accesibilidad de su producción científica, con el objetivo de acercarla a los investigadores, doctorandos, estudiantes y a la sociedad en general, ofreciendo una nueva perspectiva de difusión, utilización, citación y seguimiento de las diferentes líneas de investigación existentes en la UGR.Since 2005 the University of Granada (UGR) has implemented the DIGIBUG Project, which aims to improve visibility of and access to its scientific output so as to bring it closer to researchers, doctorate and undergraduate students and society in general, providing a new way of disseminating, using, citing and following up the different lines of enquiry at the UGR

Support at Home: Interventions to Enhance Life in Dementia (SHIELD) – evidence, development and evaluation of complex interventions

Background Dementia is a national priority and this research addresses the Prime Minister’s commitment to dementia research as demonstrated by his 2020 challenge and the new UK Dementia Research Institute. In the UK > 800,000 older people have dementia. It has a major impact on the lives of people with dementia themselves, on the lives of their family carers and on services, and costs the nation £26B per year. Pharmacological cures for dementias such as Alzheimer’s disease are not expected before 2025. If no cure can be found, the ageing demographic will result in 2 million people living with dementia by 2050. People with dementia lose much more than just their memory and their daily living skills; they can also lose their independence, their dignity and status, their confidence and morale, and their roles both within the family and beyond. They can be seen as a burden by society, by their families and even by themselves, and may feel unable to contribute to society. This programme of research aims to find useful interventions to improve the quality of life of people with dementia and their carers, and to better understand how people with dementia can be supported at home and avoid being admitted to hospital. Objectives (1) To develop and evaluate the maintenance cognitive stimulation therapy (MCST) for people with dementia; (2) to develop the Carer Supporter Programme (CSP), and to evaluate the CSP and Remembering Yesterday, Caring Today (RYCT) for people with dementia both separately and together in comparison with usual care; and (3) to develop a home treatment package (HTP) for dementia, to field test the HTP in practice and to conduct an exploratory trial. Methods (1) The MCST programme was developed for people with dementia based on evidence and qualitative work. A randomised controlled trial (RCT) [with a pilot study of MCST plus acetylcholinesterase inhibitors (AChEIs)] compared MCST with cognitive stimulation therapy (CST) only. The MCST implementation study conducted a trial of outreach compared with usual care, and assessed implementation in practice. (2) The CSP was developed based on existing evidence and the engagement of carers of people with dementia. The RCT (with internal pilot) compared the CSP and reminiscence (RYCT), both separately and in combination, with usual care. (3) A HTP for dementia, including the most promising interventions and components, was developed by systematically reviewing the literature and qualitative studies including consensus approaches. The HTP for dementia was evaluated in practice by conducting in-depth field testing. Results (1) Continuing MCST improved quality of life and improved cognition for those taking AChEIs. It was also cost-effective. The CST implementation studies indicated that many staff will run CST groups following a 1-day training course, but that outreach support helps staff go on to run maintenance groups and may also improve staff sense of competence in dementia care. The study of CST in practice found no change in cognition or quality of life at 8-month follow-up. (2) The CSP/RYCT study found no benefits for family carers but improved quality of life for people with dementia. RYCT appeared beneficial for the quality of life of people with dementia but at an excessively high cost. (3) Case management for people with dementia reduces admissions to long-term care and reduces behavioural problems. In terms of managing crises, staff suggested more costly interventions, carers liked education and support, and people with dementia wanted family support, home adaptations and technology. The easy-to-use home treatment manual was feasible in practice to help staff working in crisis teams to prevent hospital admissions for people with dementia. Limitations Given constraints on time and funding, we were unable to compete the exploratory trial of the HTP package or to conduct an economic evaluation. Future research To improve the care of people with dementia experiencing crises, a large-scale clinical trial of the home treatment manual is needed. Conclusion There is an urgent need for effective psychosocial interventions for dementia. MCST improved quality of life and was cost-effective, with benefits to cognition for those on AChEIs. MCST was feasible in practice. Both CSP and RYCT improved the quality of life of people with dementia, but the overall costs may be too high. The HTP was useful in practice but requires evaluation in a full trial. Dementia care research may improve the lives of millions of people across the world. Trial registrations Current Controlled Trials ISRCTN26286067 (MCST), ISRCTN28793457 (MCST implementation) and ISRCTN37956201 (CSP/RYCT). Funding This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 5, No. 5. See the NIHR Journals Library website for further project information