26,427 research outputs found
Recommended from our members
Independence at Risk: Older Californians With Disabilities Struggle to Remain at Home as Public Supports Shrink
Presents findings about aging Californians with disabilities who depend on paid public programs and unpaid help to live at home. Makes policy recommendations, including consolidating long-term care programs and enhancing support for caregivers
Development and evaluation of silent reading exercises for grade one,
Thesis (M.A.)--Boston Universit
Fluctuations of the Casimir-like force between two membrane inclusions
Although Casimir forces are inseparable from their fluctuations, little is
known about these fluctuations in soft matter systems. We use the membrane
stress tensor to study the fluctuations of the membrane-mediated Casimir-like
force. This method enables us to recover the Casimir force between two
inclusions and to calculate its variance. We show that the Casimir force is
dominated by its fluctuations. Furthermore, when the distance d between the
inclusions is decreased from infinity, the variance of the Casimir force
decreases as -1/d^2. This distance dependence shares a common physical origin
with the Casimir force itself.Comment: 5 pages, 3 figure
Generalization of the effective Wiener-Ikehara theorem
International audienceWe consider the classical WienerâIkehara Tauberian theorem, with a generalized condition of slow decrease and some additional poles on the boundary of convergence of the Laplace transform. In this generality, we prove the otherwise known asymptotic evaluation of the transformed function, when the usual conditions of the Wiener-Ikehara theorem hold. However, our version also provides an effective error term, not known thus far in this generality. The crux of the proof is a proper asymptotic variation of the lemmas of Ganelius and Tenenbaum, also constructed for the sake of an effective version of the WienerâIkehara theorem
Fluctuations and Pinch-Offs Observed in Viscous Fingering
Our experiments on viscous (Saffman-Taylor) fingering in Hele-Shaw channels
reveal several phenomena that were not observed in previous experiments. At low
flow rates, growing fingers undergo width fluctuations that intermittently
narrow the finger as they evolve. The magnitude of these fluctuations is
proportional to Ca^{-0.64}, where Ca is the capillary number, which is
proportional to the finger velocity. This relation holds for all aspect ratios
studied up to the onset of tip instabilities. At higher flow rates, finger
pinch-off and reconnection events are observed. These events appear to be
caused by an interaction between the actively growing finger and suppressed
fingers at the back of the channel. Both the fluctuation and pinch-off
phenomena are robust but not explained by current theory.Comment: 6 pages, 3 figures; to appear in Proceedings of the Seventh
Experimental Chaos Conferenc
High fat diet causes depletion of intestinal eosinophils associated with intestinal permeability.
The development of intestinal permeability and the penetration of microbial products are key factors associated with the onset of metabolic disease. However, the mechanisms underlying this remain unclear. Here we show that, unlike liver or adipose tissue, high fat diet (HFD)/obesity in mice does not cause monocyte/macrophage infiltration into the intestine or pro-inflammatory changes in gene expression. Rather HFD causes depletion of intestinal eosinophils associated with the onset of intestinal permeability. Intestinal eosinophil numbers were restored by returning HFD fed mice to normal chow and were unchanged in leptin-deficient (Ob/Ob) mice, indicating that eosinophil depletion is caused specifically by a high fat diet and not obesity per se. Analysis of different aspects of intestinal permeability in HFD fed and Ob/Ob mice shows an association between eosinophil depletion and ileal paracelullar permeability, as well as leakage of albumin into the feces, but not overall permeability to FITC dextran. These findings provide the first evidence that a high fat diet causes intestinal eosinophil depletion, rather than inflammation, which may contribute to defective barrier integrity and the onset of metabolic disease
Fluctuations and Pinch-Offs Observed in Viscous Fingering
Our experiments on viscous (Saffman-Taylor) fingering in Hele-Shaw channels
reveal several phenomena that were not observed in previous experiments. At low
flow rates, growing fingers undergo width fluctuations that intermittently
narrow the finger as they evolve. The magnitude of these fluctuations is
proportional to Ca^{-0.64}, where Ca is the capillary number, which is
proportional to the finger velocity. This relation holds for all aspect ratios
studied up to the onset of tip instabilities. At higher flow rates, finger
pinch-off and reconnection events are observed. These events appear to be
caused by an interaction between the actively growing finger and suppressed
fingers at the back of the channel. Both the fluctuation and pinch-off
phenomena are robust but not explained by current theory.Comment: 6 pages, 3 figures; to appear in Proceedings of the Seventh
Experimental Chaos Conferenc
- âŠ