11,283 research outputs found
A systematic experimental investigation of significant parameters affecting model tire hydroplaning
The results of a comprehensive parametric study of model and small pneumatic tires operating on a wet surface are presented. Hydroplaning inception (spin down) and rolling restoration (spin up) are discussed. Conclusions indicate that hydroplaning inception occurs at a speed significantly higher than the rolling restoration speed. Hydroplaning speed increases considerably with tread depth, surface roughness and tire inflation pressure of footprint pressure, and only moderately with increased load. Water film thickness affects spin down speed only slightly. Spin down speed varies inversely as approximately the one-sixth power of film thickness. Empirical equations relating tire inflation pressure, normal load, tire diameter and water film thickness have been generated for various tire tread and surface configurations
Truncated unity functional renormalization group for multiband systems with spin-orbit coupling
Although the functional renormalization group (fRG) is by now a
well-established method for investigating correlated electron systems, it is
still undergoing significant technical and conceptual improvements. In
particular, the motivation to optimally exploit the parallelism of modern
computing platforms has recently led to the development of the
"truncated-unity" functional renormalization group (TU-fRG). Here, we review
this fRG variant, and we provide its extension to multiband systems with
spin-orbit coupling. Furthermore, we discuss some aspects of the implementation
and outline opportunities and challenges ahead for predicting the ground-state
ordering and emergent energy scales for a wide class of quantum materials.Comment: consistent with published version in Frontiers in Physics (2018
Structural Neuroimaging of Anorexia Nervosa: Future Directions in the Quest for Mechanisms Underlying Dynamic Alterations.
Anorexia nervosa (AN) is a serious eating disorder characterized by self-starvation and extreme weight loss. Pseudoatrophic brain changes are often readily visible in individual brain scans, and AN may be a valuable model disorder to study structural neuroplasticity. Structural magnetic resonance imaging studies have found reduced gray matter volume and cortical thinning in acutely underweight patients to normalize following successful treatment. However, some well-controlled studies have found regionally greater gray matter and persistence of structural alterations following long-term recovery. Findings from diffusion tensor imaging studies of white matter integrity and connectivity are also inconsistent. Furthermore, despite the severity of AN, the number of existing structural neuroimaging studies is still relatively low, and our knowledge of the underlying cellular and molecular mechanisms for macrostructural brain changes is rudimentary. We critically review the current state of structural neuroimaging in AN and discuss the potential neurobiological basis of structural brain alterations in the disorder, highlighting impediments to progress, recent developments, and promising future directions. In particular, we argue for the utility of more standardized data collection, adopting a connectomics approach to understanding brain network architecture, employing advanced magnetic resonance imaging methods that quantify biomarkers of brain tissue microstructure, integrating data from multiple imaging modalities, strategic longitudinal observation during weight restoration, and large-scale data pooling. Our overarching objective is to motivate carefully controlled research of brain structure in eating disorders, which will ultimately help predict therapeutic response and improve treatment
IL-3-Mediated Osteoblast Inhibition in Multiple Myeloma
Multiple myeloma is a plasma cell malignancy that localizes to the bone. It is diagnosed in 15,000 new patients per year, making it the second most common hematologic malignancy. The major source of morbidity in these patients is due to bone destruction induced by the myeloma cells leading to severe bone pain and pathologic fractures. Bone destruction in myeloma is mediated by an increase in osteoclast activity, the cells that normally resorb bone, with a concomitant decrease in osteoblast number and function, the cells that normally rebuild bone. The cause of the decrease in osteoblasts is not well understood. Interleukin-3 (IL-3) is upregulated in myeloma compared to normal controls and can mediate osteoclast activation in myeloma. This dissertation investigates the potential role of IL-3 as an osteoblast inhibitor in myeloma. First, IL-3 blocked osteoblast differentiation in a primary murine osteoblast culture system in a dose-dependant manner. Importantly, IL-3-mediated osteoblast inhibition occurred at IL-3 levels present in bone marrow samples from patients with myeloma. IL-3 did not inhibit osteoblast differentiation in cell lines, indicating that the IL-3 effects were not direct. Conversely, IL-3 caused proliferation in CD45+ hematopoietic cells present in the primary murine cultures, and depletion of CD45+ cells from these cultures resulted in a loss of IL-3 inhibition of osteoblast differentiation. Reconstitution of cultures with CD45+ cells resulted in restoration of the ability of IL-3 to inhibit osteoblasts. These CD45+ cells were shown to be CD11b+ and in the monocyte/macrophage lineage. Further studies were conducted into the mechanism of IL-3-mediated osteoblast inhibition. Cell-to-cell contact was required between osteoblasts and CD45+ hematopoietic cells, and separation of the cell population by transwell cultures abolished IL-3 inhibition of osteoblasts. Transcript levels of several integrins expressed on osteoblasts were not increased by treatment with IL-3, indicating that increased binding of CD45+ cells to osteoblasts is not the mechanism required for osteoblast inhibition. Contact between CD45+ cells and osteoblasts could result in increased expression of a juxtacrine factor that mediates IL-3 inhibition of osteoblasts. In myeloma, IL-3 can mediate proliferation of malignant cells, stimulation of osteoclast activity, and inhibition of osteoblast activity, which ultimately leads to exacerbation of lytic lesions in these patients. Thus, IL-3 is a potential target for myeloma therapy
Invoice, A. Ehrlich and Bro.- Mrs. M. J. Glover, March 1, 1902
Document: To Mrs. M.J. Glover, Cohens Blluff, [South Carolina], listing items ordered, Marked paid by A. Ehrlich & Bro. Intialed by HJP
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