2,589 research outputs found
Progression of extrapyramidal signs in Alzheimer's disease. clinical and neuropathological correlates
Extrapyramidal signs (EPS) are frequent in Alzheimer's disease (AD) and core manifestation of related diseases, i.e., dementia with Lewy bodies and Parkinson's disease; furthermore, Lewy bodies and AD-type pathology occur in all three conditions
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The dimensions of therapists\u27 thoughts in response to therapy failures.
This research study has explored the kinds of thoughts that therapists report having had in response to their experiences with therapy failures. The central goal was to develop a model for organizing therapists\u27 thoughts to form a basis for further investigations into therapists\u27 conceptual processes for coping with and learning from therapy failures. The methodological approaches used in this study were designed to conform to a set of hermeneutic and social constructionist assumptions about the development and function of meaning making, as it applies to both psychological research and the therapeutic relationship. Thus, the research methods replicated a social construction process, using a community of participants for all stages of data gathering and analyses. The application of Thought Listing and Multiple Sorting Procedures in combination with Cluster and Multidimensional Scaling Analyses yielded a three dimensional solution with which to organize these therapists\u27 thoughts. Additional findings suggest that the ways in which therapists examine therapy failures is socially constructed and may function to preserve therapists\u27 core beliefs. The three dimensional solution challenges the usefulness of an exclusively causal model for understanding therapists\u27 reflections on failures
Fruits and frugivory in neotropical primates and in Amazonian flooded and unflooded forests
The richness and resilience of tropical forest ecosystems are best described by the
myriad of ecological interactions linking co-occurring species together. The many
functions previously served by ecological links are often only detected once these links
are lost. Of particular interest in this regard are the mutualistic networks between
fruiting plants and vertebrate frugivores, whose interdependent relationship is
fundamental to the functioning of tropical forests. This thesis examined these fruitfrugivore
interactions at two contrasting scales, and using two different approaches. On
a landscape scale in western Brazilian Amazonia, the focus was on a community-wide
assessment, with particular attention paid to the differences between two highly
divergent but adjacent species-rich forest types, seasonally-flooded várzea forests and
unflooded terra firme forests. As part of this comparison, the powerful role of the
annual flood pulse was shown to determine both spatial patterns of forest structure and
temporal patterns of fruit production. The strong influence of this seasonal cycle was
apparent in the adaptive traits observed in plants and animals, with corresponding
effects upon their networks of interactions. The role of frugivore body size as an
important trait in relation to the degree of frugivory within consumers was emphasised
via one of the most extensive compilations on the feeding ecology of any frugivorous
vertebrate taxon. By amassing the observations of feeding records accumulated over
several decades of neotropical primate field research, and accounting for the highly
variable levels of sampling effort among primate species, the prevalence of frugivory at
the mid-high spectrum of body mass was confirmed. This continental-scale metaanalysis
also revealed that, despite representing arguably the most observable and wellstudied
group of vertebrate frugivores in tropical forests worldwide, most primate
species were heavily undersampled in terms of the richness of fruits known to occur in
their diets. These astounding gaps in our cumulative knowledge highlight the challenges
faced in assembling comprehensive fruit-frugivore networks for entire communities,
where the diets of most consumers are even more poorly understood than for primates.
This is particularly pertinent in the face of ever-increasing threats to ecosystems
comprised of, and sustained by, these complex webs of interactions
The cultural transformation of large Chinese enterprises into internationally competitive corporations: Case studies of Haier and Huawei
The Chinese government has recently introduced a policy requiring all large Chinese business corporations to transform their corporate cultures with the aim of increasing their competitiveness on the international stage. This paper traces the origins of the policy to the outstanding performance of a small number of Chinese firms since the late 1980s, a phenomenon attributed by the CEOs of these firms to effective implementation of cultural values change among their workforces. We give detailed accounts of two such firms, Haier Group and Huawei Technologies, demonstrating how they have utilized cultural management techniques to improve their employees' performance. We also identify some negative aspects of their approach to cultural management that may impede these firms in their efforts to become truly international corporations. © 2011 The Chinese Economic Association - UK
Technology Preparedness and the Impact on a High-Quality Remote Learning Experience: Lessons From COVID-19
The COVID-19 crisis has highlighted the role of remote learning in higher education. Increased investments and understanding of the transition to remote learning today will yield access to high-quality learning. Using data from an institution with a diverse student population, the purpose of this study was to explore students’ transition to remote learning during the COVID-19 pandemic by examining aspects within the course that contributed to perceptions of a high-quality remote learning experience. Five elements of the remote learning experience were statistically significant predictors of course quality ratings: ratings of the quality of student supports (Academic Advising, Tutoring, Internships, Financial Aid, etc.), ratings of connectedness to instructors in at least one class, the use of many learning activities by instructors, clear course organization by instructors, and clear communication used by instructors. Analysis of qualitative student interviews reinforced these findings and provided further support for the importance of reliable technology during remote learning
Nonperturbative Vertices in Supersymmetric Quantum Electrodynamics
We derive the complete set of supersymmetric Ward identities involving only
two- and three- point proper vertices in supersymmetric QED. We also present
the most general form of the proper vertices consistent with both the
supersymmetric and U(1) gauge Ward identities. These vertices are the
supersymmetric equivalent of the non supersymmetric Ball-Chiu vertices.Comment: seventeen pages late
Non-linear relationships between density and demographic traits in three Aedes species
Understanding the relationship of population dynamics to density is central to many ecological investigations. Despite the importance of density-dependence in determining population growth, the empirical relationship between density and per capita growth remains understudied in most systems and is often assumed to be linear. In experimental studies of interspecifc competition, investigators often evaluate the predicted outcomes by assuming such linear relationships, ftting linear functions, and estimating parameters of competition models. In this paper, we experimentally describe the shape of the relationship between estimated population rate of change and initial density using laboratory-reared populations of three mosquito species. We estimated per capita growth rate for these experimental populations over a 30-fold range of larval densities at a standard resource abundance. We then compared fts of linear models and several diferent nonlinear models for the relationship of estimated rate of change and density. We fnd that that the relationship between density and per capita growth is strongly non-linear in Aedes aegypti (Linnaeus), Aedes albopictus (Skuse), and Aedes triseriatus (Say) mosquitoes. Components of population growth (survivorship, development time, adult size) are also nonlinearly related to initial density. The causes and consequences of this nonlinearity are likely to be important issues for population and community ecology
Multitrophic diversity effects of network degradation
Predicting the functional consequences of biodiversity loss in realistic, multitrophic communities remains a challenge. No existing biodiversity-ecosystem function study to date has simultaneously incorporated information on species traits, network topology, and extinction across multiple trophic levels, while all three factors are independently understood as critical drivers of post-extinction network structure and function. We fill this gap by comparing the functional consequences of simulated species loss both within (monotrophic) and across (bitrophic) trophic levels, in an ecological interaction network estimated from spatially explicit field data on tropical fecal detritus producer and consumers (mammals and dung beetles). We simulated trait-ordered beetle and mammal extinction separately (monotrophic extinction) and the coextinction of beetles following mammal loss (bitrophic extinction), according to network structure. We also compared the diversity effects of bitrophic extinction models using a standard monotrophic function (the daily production or consumption of fecal detritus) and a unique bitrophic functional metric (the proportion of daily detritus production that is consumed). We found similar mono- and bitrophic diversity effects, regardless of which species traits were used to drive extinctions, yet divergent predictions when different measures of function were used. The inclusion of information on network structure had little apparent effect on the qualitative relationship between diversity and function. These results contribute to our growing understanding of the functional consequences of biodiversity from real systems and underscore the importance of species traits and realistic functional metrics to assessments of the ecosystem impacts of network degradation through species loss
Population recovery, seasonal site fidelity and daily activity of pirarucu (Arapaima spp.) in an Amazonian floodplain mosaic
1. Pirarucu (Arapaima spp.) are the world's largest scaled freshwater fish, reaching 3 m in length and >200 kg in weight. Historical overfishing has devastated populations of this remarkable fish across Amazonian floodplains, but community‐based management programmes are now stimulating the recovery of wild populations.
2. Pirarucu have evolved a unique set of life history traits, some of which have important implications for population management. Individuals exhibit lateral annual migration patterns during the prolonged annual flood pulse, entering flooded forests to reproduce and forage. During this period, although managed fish stocks become less monopolisable by local communities responsible for managing protected lakes, pirarucu can occupy and reproduce in new environments and thus potentially contribute to population recovery.
3. Here, we show a strong pattern of pirarucu (Arapaima cf. gigas) population recovery under community‐based management in an area along the Juruá River, in western Brazilian Amazonia. We show evidence of population recovery even outside formal protected areas, reinforcing the suitability of pirarucu community‐based management as a powerful tool for both biodiversity conservation and the improvement of local livelihoods. We also show pirarucu movements across a floodplain mosaic—including lakes, the main river channel, tributary streams, and flooded forests—during the wet season.
4. Our results support evidence of site fidelity among migrating pirarucu, justifying the high effort invested by local communities in seasonally protecting lakes from poachers and illegal fishers. Finally, restricted daily movement patterns by pirarucu support the suitability of population estimates based on day‐time counts because the chance of double counting is substantially reduced during the day when these counts are conducted. We highlight the strong suitability of this species for community‐based management, since they can: (1) replenish new environments during the wet season through migration and possibly also reproduction; and (2) be efficiently harvested during the dry season, delivering social and ecological benefits at large spatial scales.
5. Positive examples of fisheries management, which align biodiversity conservation and social development, are important for building optimism, and influencing local and international stakeholders. Our study shows how engaging and empowering local communities to help monitor the movement ecology of target species can be an effective strategy to support the sustainable management of aquatic resources in tropical environments
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