2,372 research outputs found
Finiteness and orbifold Vertex Operator Algebras
In this paper, I investigate the ascending chain condition of right ideals in
the case of vertex operator algebras satisfying a finiteness and/or a
simplicity condition. Possible applications to the study of finiteness of
orbifold VOAs is discussed.Comment: 12 pages, comments are welcom
Negative-pressure pulmonary edema presented with concomitant spontaneous pneumomediastinum: Moore meets Macklin
Negative-pressure pulmonary edema is an unusual complication mainly associated with general anesthesia. It is caused by excessive negative intrathoracic pressure following a deep inspiration against an acute airway obstruction. The resultant decreased intrathoracic pressure amplifies venous return to the right heart and increases pulmonary capillary wedge pressure that can be further amplified by massive sympathetic discharge due to hypoxia. The combination of increased venous return and pulmonary capillary wedge pressure favours the shift of fluid into the pulmonary interstitium with resultant pulmonary edema. Conversely, spontaneous pneumomediastinum (SP) results from alveolar rupture following an excessive positive intrathoracic pressure. The air leaks out of the alveoli and along the perivascular space toward the mediastinum. We experienced a case of negative pulmonary edema which presented in association with SP. Pneumomediastinum is probably caused by an excessive positive intrathoracic pressure for a subsequent expiration against a closed airway. In the present case, both complications resolved with conservative management
Optimum Filter Synthesis with DPLMS Method for Energy Reconstruction
Optimum filters are granted increasing recognition as valuable tools for
parametric estimation in many scientific and technical fields. The DPLMS
method, introduced some twenty years ago, is effective among the synthesis
algorithms since it derives the optimum filters directly from the experimental
signal and noise waveforms. Two new extensions of the DPLMS method are here
presented. The first one speeds up the synthesis phase and improves the energy
estimation by synthesizing optimum filters with automatically designed flat-top
length. The second one improves the quality of parameter estimation in
multi-channel systems by taking advantage of the inter-channel noise
correlation properties. The theoretical and functional aspects behind the DPLMS
method for optimum filter synthesis are first recalled and illustrated in more
detail. The two new DPLMS extensions are subsequently introduced from the
theoretical viewpoint and more thoroughly considered from the applicative
perspective. The DPLMS optimum filters have been applied first to simulated
signals with various amounts and characteristics of superimposed noise and then
to the experimental waveforms acquired from a solid-state Ge detector. The
results obtained are considered from both the absolute viewpoint and in
comparison with those of more traditional, suboptimal filters. The results
demonstrate the effectiveness of the two new DPLMS extensions. For
single-channel energy estimations, the optimum filters provide comparatively
better results than the other filters. The DPLMS multi-channel optimum filters
further enhance the quality of the estimations, compared to single-channel
optimum filters, with non-negligible inter-channel noise correlation. The
effectiveness and robustness of the DPLMS method in synthesizing high-quality
filters for energy estimation will be tested soon within leading-edge
multi-channel physics experiments.Comment: 15 pages, 13 figure
Expression of angiogenic regulators, VEGF and leptin, is regulated by the EGF/PI3K/STAT3 pathway in colorectal cancer cells.
Abstract
Both leptin and vascular endothelial growth factor (VEGF) are growth and angiogenic cytokines that are upregulated in different types of cancer and have been implicated in neoplastic progression. Here we investigated the molecular mechanism by which leptin and VEGF expression are regulated in colon cancer by epidermal growth factor (EGF). In colon cancer cell line HT-29, EGF induced the binding of signal transducer and activator transcription 3 (STAT3) to STAT3 consensus motifs within the VEGF and leptin promoters and stimulated leptin and VEGF mRNA and protein synthesis. All these EGF effects were significantly blocked when HT-29 cells were treated with an inhibitor of the phosphoinositide 3-kinase (PI3K) pathway, LY294002, or with small interfering RNA (siRNA) targeting STAT3. Thus, our study identified the EGF/PI3K/STAT3 signaling as an essential pathway regulating VEGF and leptin expression in EGF-responsive colon cancer cells. This suggests that STAT3 pathways might constitute attractive pharmaceutical targets in colon cancer patients where anti-EGF receptor drugs are ineffective
Ligaclip for Preauricular Skin Tags in the Newborn
Introduction Skin tags are benign lesions, that often represent only an aesthetic problem; if subjected to trauma, they can occasionally bleed with possible infection and pain. When they occur in the preauricular region, attention should be paid to the diagnosis and approach; in fact, controversy exists in the differential diagnosis between hair follicle nevi, accessory tragus, and skin tag. Misdiagnosis and failure of treatment can lead to serious consequences, such as chondritis. Materials and Methods In our retrospective study, we evaluated 19 newborns affected by single, unilateral skin tag in the preauricular region. Each patient underwent a careful clinical examination; lesions without a pilosebaceous unit and with a thin, soft pedicle were treated in the nursery with Ligaclip (Johnson & Johnson). Results Skin tag falls between day 7 and 10. We had no cases of edema, cellulitis, clip loss, or bleeding. Scarring results were extremely satisfactory at 3-month follow-up. Conclusion We believe that after a careful clinical examination, cases of skin tags in the preauricular area can be selected and treated with Ligaclip. This procedure can be considered rapid, safe, economical, and simple in the newborn patients
Novel time-resolved camera based on compressed sensing
Time-resolved cameras with high temporal resolution (down to ps) enable a huge set of novel applications ranging from biomedicine and environmental science to material and device characterization. In this work, we propose, and experimentally validate, a novel detection scheme for time-resolved imaging based on a compressed sampling approach. The proposed scheme unifies into a single element all the required operations, i.e. space modulation, space integration and time-resolved detection, paving the way to dramatic cost reduction, performance improvement and ease of use
Immunodepletion in xenotransplantation
Xenograft transplantation is perhaps the most immunologically difficult problem in transplantation today. An overwhelming hyperacute rejection reaction (HAR) occurs within minutes of organ implantation. Preformed antibodies are thought to initiate this process. We used a pig-to-dog renal xenograft transplant model and investigated methods of decreasing the severity of hyperacute rejection. Female pigs weighing 15-20 kg were used as donors. Recipients were mongrel dogs weighing 15-25 kg. Experimental dogs were all given a number of treatments of IgG depletion using an antibody removal system (Dupont-Excorim). This machine immunoadsorbs plasma against a column containing immobilized staphylococcal protein A, which is known to bind the IgG Fc receptor. An 84% reduction in the IgG levels and a 71% reduction in IgM levels was achieved. Postoperative assessment was made of urine output, time to onset of HAR, and histopathological examination of the rejected kidneys. Although cross-matches between donor lymphocytes and recipient sera remained strongly positive in the treated dogs, there was a two- to fourfold reduction in the titers. The time to onset of HAR was prolonged in the experimental group, and the urine output was increased slightly. The histopathologic changes in the experimental group generally showed signs of HAR, but of less intensity than in the nonimmunodepleted control group. © 1990 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted
- …