620 research outputs found

    Educational Software: Why are Teachers Dissatisfied

    Get PDF
    For adequate computer software teachers and publishers must consult and work together

    Sediment-Induced Amplification in the Northeastern United States: a Case Study in Providence, Rhode Island

    Get PDF
    We employed ambient-noise measurements to assess the potential for seismic site response in sediment-filled valleys that intersect beneath downtown Providence, Rhode Island. At eight valley stations and at two sites on an adjacent bedrock highland, we recorded ground motion from two types of sources: pile drivers at a local construction site and ambient microtremors. At all valley sites where sediment thicknesses exceed 10 m, spectral ratios contain amplitude peaks at frequencies of 1.5 to 3.0 Hz. In contrast, spectral ratios from the two sites on the bedrock highland where sediment cover is less than 4-m thick are relatively flat within this frequency range. A variety of borehole logs identified two fundamental sediment types (soft sediment and a consolidated glacial till) and were used to map layer thicknesses over the entire study region. Refraction data constrained P-wave velocity in the bedrock to be 3680 ± 160 m/sec and indicated two soft-sediment layers with P-wave velocities of 300 ± 50 and 1580 ± 120 m/sec. Using a one-dimensional reflection matrix technique, we matched the spectral-ratio peak observed at each valley site with the frequency of fundamental resonance predicted for local layer thicknesses and velocities. A positive correlation between the best-fitting soft-sediment velocities and bedrock depth may reflect greater compaction in the deepest sediments or a locally two-dimensional sediment resonance at the deepest sediment sites. We conclude that unconsolidated sediment layers under downtown Providence have the potential to amplify earthquake ground motion at frequencies damaging to engineered structures

    A Brief Centennial Bibliography Of Resources On The History Of The American Sociological Society/Association

    Get PDF
    Celebrating the centennial of the American Sociological Association provides the ritual occasion and reinforces the intellectual rationale for collectively exploring our professional and organizational roots. To guide us on our way, we have compiled a brief bibliography of relevant materials and exemplars that explicate the early history of the American Sociological Society and – to some degree – its subsequent evolution (the line separating “history” from “current events” is not always easily drawn). Practicing extreme parsimony, we have intentionally excluded literally thousands of otherwise important and instructive published works that focus primarily on specific departments of sociology, the ideas and accomplishments of individual sociologists, the development of sociological theories, the general intellectual history of the discipline as a whole, and myriad other matters of obvious historical and disciplinary interest. We hasten to add, however, that the structure and practical scope of a much more inclusive bibliography is now under consideration and is soon to be implemented. In the interim, we provide here a small down payment: a narrowly defined set of references for selected articles – and still fewer monographs – that specifically address, in various ways, the founding era and subsequent evolution of the American Sociological Society as a professional organization. To these citations, we add lists of relevant journals, abstracts, indexes and databases, and append the locations of archival deposits for the first ten presidents of the American Sociological Society, with the hope of encouraging ever more scholarship on the early history of the ASS/ASA per se. Corrections and suggested additions to this bibliography, focused specifically on the history of the ASS/ASA, are welcomed by the committee. [Submitted December 2004 by the Centennial Bibliography Project Committee]

    A Brief Centennial Bibliography Of Resources On The History Of The American Sociological Society/Association

    Get PDF
    Celebrating the centennial of the American Sociological Association provides the ritual occasion and reinforces the intellectual rationale for collectively exploring our professional and organizational roots. To guide us on our way, we have compiled a brief bibliography of relevant materials and exemplars that explicate the early history of the American Sociological Society and – to some degree – its subsequent evolution (the line separating “history” from “current events” is not always easily drawn). Practicing extreme parsimony, we have intentionally excluded literally thousands of otherwise important and instructive published works that focus primarily on specific departments of sociology, the ideas and accomplishments of individual sociologists, the development of sociological theories, the general intellectual history of the discipline as a whole, and myriad other matters of obvious historical and disciplinary interest. We hasten to add, however, that the structure and practical scope of a much more inclusive bibliography is now under consideration and is soon to be implemented. In the interim, we provide here a small down payment: a narrowly defined set of references for selected articles – and still fewer monographs – that specifically address, in various ways, the founding era and subsequent evolution of the American Sociological Society as a professional organization. To these citations, we add lists of relevant journals, abstracts, indexes and databases, and append the locations of archival deposits for the first ten presidents of the American Sociological Society, with the hope of encouraging ever more scholarship on the early history of the ASS/ASA per se. Corrections and suggested additions to this bibliography, focused specifically on the history of the ASS/ASA, are welcomed by the committee. [Submitted December 2004 by the Centennial Bibliography Project Committee]

    Leaf spectral clusters as potential optical leaf functional types within California ecosystems

    Get PDF
    Our ability to measure and map plant function at multiple ecological scales is critical for understanding current and future changes in Earth's ecosystems and the global carbon budget. Conventional plant functional types (cPFTs) based on a few productivity-related traits have been previously used to simplify and represent major differences in global plant functions, but more recent research has directly focused on the use of functional trait information. Still, sampling limitations have constrained efforts to truly understand the variance and covariance of functional traits globally. Reflectance spectra offer a fast, repeatable, simultaneous measurement of a wide variety of leaf functional traits and could be used to optically define leaf functional types. To evaluate this concept, we measured leaf reflectance from a wide range of species in a diverse set of ecosystems across central and northern California, including observations from multiple individuals, sites, and seasons. Using principal components analysis, we analyzed spectral variation in relation to categorical attributes such as species and cPFTs, as well as to a set of functional trait metrics calculated from the spectra. We found the first three principal components (PCs) to be weakly related to categorical attributes and more strongly related to spectrally-derived functional metrics. Each PC was more strongly associated with different portions of the spectrum and contained different functional information. We applied a hybrid clustering algorithm to the PC coordinates of the observations to define potential optical leaf functional types. Twelve spectral clusters were identified, and these did not correspond directly to either single cPFTs or species. However, each cluster had a unique functional metric profile. Clusters represented both inter- and intra-species and cPFT functional differences driven by taxonomy, trait evolution and environmental responses, demonstrating their value as optical leaf functional types and the value of the clustering approach used here for defining optical types from leaf spectra. Our findings support the notion that cPFTs do not adequately capture differences in leaf function. They demonstrate that spectral measurements can be used to improve both the definition of PFTs as well as our knowledge regarding the covariance of functional traits within these classes

    Group cognitive behavioural therapy for stroke survivors with depression and their carers

    Get PDF
    Background: Depression in stroke survivors is common, leads to poorer outcomes and often not treated. A group cognitive behavioural therapy (CBT) program (Brainstorm) for stroke survivors with depression, and their carers has been running as part of usual care since 2007. Objective: To evaluate the implementation and acceptability of Brainstorm, a closed group intervention consisting of up to 10 sessions of education, activity planning, problem solving and thought challenging. Methods: Participating stroke survivors and their carers complete assessment measures at baseline, post-treatment and 1-month and 6-months follow-up. A mixed models for repeated measures data was conducted with depression and anxiety scores for stroke survivors (Beck Depression Inventory-II; Hospital Anxiety and Depression Scale) and the assessment of depression, anxiety and carer burden for carers. Acceptability was assessed by session attendance and written and open participant feedback upon completion of the program. Results: Forty-eight community dwelling stroke survivors and 34 carers attended Brainstorm, with a median attendance of 88% of sessions. Follow-up assessments were completed by 77% (post-treatment), 46% (1-month) and 38% (6-month) of stroke survivors. Stroke survivors’ depression scores decreased from baseline to post-treatment (p<.001); maintained at 1-month (p<.001) but not at 6-month (p=.056). Anxiety scores decreased between baseline and 1-month (p=.013). Carer burden, depression and anxiety scores at 1-month and 6-month follow-up, for carers, were all reduced when compared with baseline (p<.05). Conclusion: The Brainstorm group intervention for depression in stroke survivors appears to have been effectively implemented and is acceptable to stroke survivors and carers

    Comparison of Methods for Modeling Fractional Cover Using Simulated Satellite Hyperspectral Imager Spectra

    Get PDF
    Remotely sensed data can be used to model the fractional cover of green vegetation (GV), non-photosynthetic vegetation (NPV), and soil in natural and agricultural ecosystems. NPV and soil cover are difficult to estimate accurately since absorption by lignin, cellulose, and other organic molecules cannot be resolved by broadband multispectral data. A new generation of satellite hyperspectral imagers will provide contiguous narrowband coverage, enabling new, more accurate, and potentially global fractional cover products. We used six field spectroscopy datasets collected in prior experiments from sites with partial crop, grass, shrub, and low-stature resprouting tree cover to simulate satellite hyperspectral data, including sensor noise and atmospheric correction artifacts. The combined dataset was used to compare hyperspectral index-based and spectroscopic methods for estimating GV, NPV, and soil fractional cover. GV fractional cover was estimated most accurately. NPV and soil fractions were more difficult to estimate, with spectroscopic methods like partial least squares (PLS) regression, spectral feature analysis (SFA), and multiple endmember spectral mixture analysis (MESMA) typically outperforming hyperspectral indices. Using an independent validation dataset, the lowest root mean squared error (RMSE) values were 0.115 for GV using either normalized difference vegetation index (NDVI) or SFA, 0.164 for NPV using PLS, and 0.126 for soil using PLS. PLS also had the lowest RMSE averaged across all three cover types. This work highlights the need for more extensive and diverse fine spatial scale measurements of fractional cover, to improve methodologies for estimating cover in preparation for future hyperspectral global monitoring missions

    Application of a Mechanistic Model to Evaluate Putative Mechanisms of Tolvaptan Drug-Induced Liver Injury and Identify Patient Susceptibility Factors

    Get PDF
    Tolvaptan is a selective vasopressin V2 receptor antagonist, approved in several countries for the treatment of hyponatremia and autosomal dominant polycystic kidney disease (ADPKD). No liver injury has been observed with tolvaptan treatment in healthy subjects and in non-ADPKD indications, but ADPKD clinical trials showed evidence of drug-induced liver injury (DILI). Although all DILI events resolved, additional monitoring in tolvaptan-treated ADPKD patients is required. In vitro assays identified alterations in bile acid disposition and inhibition of mitochondrial respiration as potential mechanisms underlying tolvaptan hepatotoxicity. This report details the application of DILIsym software to determine whether these mechanisms could account for the liver safety profile of tolvaptan observed in ADPKD clinical trials. DILIsym simulations included physiologically based pharmacokinetic estimates of hepatic exposure for tolvaptan and2 metabolites, and their effects on hepatocyte bile acid transporters and mitochondrial respiration. The frequency of predicted alanine aminotransferase (ALT) elevations, following simulated 90/30 mg split daily dosing, was 7.9% compared with clinical observations of 4.4% in ADPKD trials. Toxicity was multifactorial as inhibition of bile acid transporters and mitochondrial respiration contributed to the simulated DILI. Furthermore, simulation analysis identified both pre-treatment risk factors and on-treatment biomarkers predictive of simulated DILI. The simulations demonstrated that in vivo hepatic exposure to tolvaptan and the DM-4103 metabolite, combined with these 2 mechanisms of toxicity, were sufficient to account for the initiation of tolvaptan-mediated DILI. Identification of putative risk-factors and potential novel biomarkers provided insight for the development of mechanism-based tolvaptan risk-mitigation strategies

    Cultural Transformation in Healthcare: How Well Does the Veterans Health Administration Vision for Whole Person Care Fit the Needs of Patients at an Academic Rehabilitation Center?

    Get PDF
    Background The Veterans Health Administration is undergoing a cultural transformation toward person-driven care referred to as the Whole Health System of Care. Objective This pilot study evaluated whether the Whole Health model resonates with patients of a large public university rehabilitation clinic. Methods Thirty participants completed the Veterans Health Administration's Personal Health Inventory (PHI), and six attended the course "Taking Charge of My Life and Health." Researchers analyzed PHI responses and post-course focus group transcripts. A short post-PHI survey and post-course evaluation were collected. Results Participants agreed the PHI is a simple, useful tool. The course, while well attended, did not meet participants' expectations. Participants wanted access to integrative therapies and opportunities to contribute to healthcare transformation. Conclusion Rehabilitation patients resonated with the Whole Health vision. They expressed enthusiasm for the cultural transformation represented by the model along with frustration that standard healthcare experiences fall short of this vision
    • …
    corecore