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Salem, NH, United States

Elsayed A.,University of Liverpool | Coenen F.,University of Liverpool | Jiang C.,University of Liverpool | Garcia-Finana M.,University of Liverpool | Sluming V.,Thompson SCI
Knowledge-Based Systems | Year: 2010

An approach to classifying magnetic resonance (MR) image data is described. The specific application is the classification of MRI scan data according to the nature of the corpus callosum, however the approach has more general applicability. A variation of the "spectral segmentation with multi-scale graph decomposition" mechanism is introduced. The result of the segmentation is stored in a quad-tree data structure to which a weighted variation (also developed by the authors) of the gSpan algorithm is applied to identify frequent sub-trees. As a result the images are expressed as a set frequent sub-trees. There may be a great many of these and thus a decision tree based feature reduction technique is applied before classification takes place. The results show that the proposed approach performs both efficiently and effectively, obtaining a classification accuracy of over 95% in the case of the given application. © 2009 Elsevier B.V. All rights reserved. Source

Beversdorf D.Q.,Thompson SCI | Bonab A.A.,Massachusetts General Hospital | Fischman A.J.,Massachusetts General Hospital | Weise S.B.,Massachusetts General Hospital | And 4 more authors.
Journal of Neuropsychiatry and Clinical Neurosciences | Year: 2012

The serotonergic system is implicated in disordered emotional behavior. Autism is characterized by impaired processing of emotional information. The serotonergic (5-HT) system is also critically involved in brain development, and abnormal brain synthesis of serotonin is observed in autism. Furthermore, whole blood and platelet serotonin have been reported to be elevated in autism. The authors examined the CNS serotonin system in autism in vivo. 5-HT 2 receptors were visualized by PET imaging of [ 18F]setoperone-binding in this pilot study of 6 high-functioning autistic adults and 10 matched-control participants. Autism subjects had less thalamic [ 18F]setoperone binding than controls, when covaried for age, but no difference reached significance in other areas. A negative relationship between thalamic binding and history of language impairment was also observed. Further studies will be needed to gain a clearer picture of the role of the 5-HT system in autism. © 2012 American Psychiatric Association. Source

Makarick L.J.,National Park Service | Kearsley M.J.C.,Thompson SCI | Lauver C.L.,National Park Service
Ecological Restoration | Year: 2010

The removal of non-native species is often an important restoration goal in natural areas, including national parks. There is often a positive correlation between non-native and native plant species richness, so that areas with the greatest number of native species support the greatest number of non-natives. This pattern may create both challenges and opportunities for restoration. Native species may be inadvertently damaged or killed during mechanical or chemical treatments targeted toward non-natives. However, greater numbers of native species may better colonize subsequent openings. We used data from an ongoing active management project in Grand Canyon National Park to test three predictions of plant community response to invasive tamarisk (Tamarix spp.) removal. We investigated patterns of native and nonnative species abundance and richness, compositional shifts, and the relationship between native and non-native species before and after treatments. In general, native species richness and abundance did not increase, but species composition following tamarisk removal tended to become more similar to that in uninvaded stands. Native and non-native species richness and abundance were positively correlated before tamarisk removal. While treatment successfully reduced cover of tamarisk after one to three years, our results suggest that it may not increase richness of native species during the same period. Furthermore, investigating native and non-native species relationships may be a useful tool for exploring hypotheses and consequences of restoration via invasive species removal. © 2010 by the Board of Regents of the University of Wisconsin System. Source

Barnes H.M.,Thompson SCI | Hill J.M.,Mississippi State University
Wood and Fiber Science | Year: 2016

This research investigated the effects of specimen width on the flexural properties of laboratorymanufactured, fire retardant-treated strandboard. In this study, fire retardant-treated and untreated 864- by 864- by 10.5-mm strandboard panels were manufactured in the laboratory. Each panel was edge trimmed and cut into five specimens of various widths. Each specimen was then tested in four-point flexure across a 648-mm span. We assessed the effect of strandboard specimen width on the stability of mean and variance estimates. It is critical to recognize specimen width as an important experimental factor because the size and orientation of individual flakes and strands in narrow-width strandboard test specimens can influence the magnitude and variability of test results. The bending properties of 305-mm-wide strandboard specimens, and to a lesser extent those of 203-mm-wide specimens, were consistently greater than the 102- and 152-mm-wide treated groups. Variability of flexure results, based on coefficient of variation, was for the most part uniform. The internal bond strength was consistent at all widths tested. © 2016 by the Society of Wood Science and Technology. Source

Shnaider P.,Ryerson University | Vorstenbosch V.,Thompson SCI | Macdonald A.,Us Va National Center For Ptsd | Macdonald A.,Boston University | And 4 more authors.
Journal of Traumatic Stress | Year: 2014

This study conducted secondary analyses of a published trial and sought to determine if different domains of psychosocial functioning (e.g., daily living, work, nonfamily relationships) improved following trauma-focused treatment for posttraumatic stress disorder (PTSD). Cognitive processing therapy (CPT), an empirically supported treatment that involves evaluating trauma-related beliefs and written trauma accounts, was compared to its components: CPT without the written accounts or written accounts only in a sample of 78 women with PTSD secondary to interpersonal violence. Overall and individual domains of functioning significantly improved with treatment and results were similar across treatment groups, Fs (2, 150) ≥ 11.87, ps < .001. Additionally, we investigated whether changes in different PTSD symptom clusters were associated with outcomes in domains of psychosocial functioning, after collapsing across treatment condition. Multiple hierarchical linear regression analyses revealed that overall clinician-assessed PTSD symptom reduction was associated with outcomes in all domains of functioning, βs = .44 to .68, ps < .001. Additionally, improvements in the emotional numbing symptom cluster were associated with outcomes in the nonfamily relationships domain, β = .42, p < .001, and improvements in the hyperarousal symptom cluster were associated with outcomes in the overall, daily living, and household tasks domains, βs = .34 to .39, ps < .01. Results suggest that it may be important to monitor improvements in emotional numbing and hyperarousal symptoms throughout treatment to increase the likelihood of changes in psychosocial functioning. © 2014. Source

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