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31.
New mobile computing technologies require new paradigms for infrastructure and interaction with mobile and networked devices. For building smart mobile companions for new intelligent services, a number of challenges have to be addressed. We argue that artificial intelligence is a key to a new generation of mobile systems. In this introduction to AI in mobile systems, we present some of the challenges and solutions in this exciting field of research. 相似文献
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Vikki Ambrose John H Miller Stuart J Dickson Scott Hampton Penelope Truman Rodney A Lea Jefferson Fowles 《Nicotine & tobacco research》2007,9(8):793-799
The effect of total particulate matter (TPM) from cigarette smoke on the expression and binding properties of nicotinic acetylcholine receptors (nAChRs) was investigated using a human neuroblastoma cell line (SH-SY5Y). TPM but not nicotine on its own inhibited cell growth at nicotine concentrations above 5 microM. To examine effects on nAChR expression, intact cells were incubated with 3H-epibatidine, and a Bmax of 13 fmoles/10(5) cells (7.8 x 10(4) binding sites/cell) was measured in unexposed cells as well as in cells treated with 2 microM nicotine alone or with TPM containing 2 microM nicotine. Using Scatchard analysis, we measured a Kd of 0.3 nM for 3H-epibatidine binding to nAChRs. This Kd was increased to 1.3 nM by addition of nicotine or TPM extract, both at 2 microM nicotine. Bmax, however, was unaffected, suggesting competitive binding of nicotine to its receptor. Short-term and prolonged 3-day exposures of SH-SY5Y cells to either TPM or nicotine at nicotine concentrations ranging from 0.2 microM to 20 microM increased specific binding, suggesting upregulation of nAChR expression. Most significant, binding was consistently greater in cells pretreated with TPM than in cells pretreated with nicotine. We conclude that TPM contains compounds that are toxic to cells at high concentrations (cell growth inhibition) but that do not compete with nicotine for binding to nAChRs (Scatchard analysis). These non-nicotinic compounds are capable of increasing the expression of one or more of the nAChR subunits. Furthermore, our cell culture assay provides a useful in vitro model for assessing the relative addictiveness of different tobacco products, including that of non-nicotine components. 相似文献
34.
Greg Foliente Michael Ambrose Dong Chen Zhengen Ren Urban Systems Program CSIRO Sustainable Ecosystems 《建筑技艺》2011,(9)
1背景简介在澳大利亚,民用住宅已经成为碳排放增长较快的板块之一.预计在2020年,民用住宅将比1990年增加61%,因此,想要达到澳大利亚的以2000年为基准,在2020年和2050年相继减排5%和80%的目标,需要对将建的和已建的民用住宅进行大量的碳减排.2007年,为了倡导民用住宅的减排和维护国家未来的持续发展,澳大利亚联邦科学院( CSIRO)的能源转型研究中心设立了澳大利亚零碳房( AusZEH)项目,致力于展示和评估适用于澳大利亚的低碳民用住宅技术. 相似文献
35.
It can be difficult for new faculty to get the information they need on issues such as teaching, advising, and setting up a research program. While some have excellent mentors, others have come to rely on trial and error or word of mouth. In 1996, the NSF Engineering Education Scholars Workshop began at Carnegie Mellon University to address the needs of new and future engineering faculty by:
- ? providing professional teaching development;
- ? offering guidance in supervising graduate students and conducting research;
- ? discussing likely engineering education and research challenges in the 21st century; and
- ? providing intellectual and social support with colleagues.
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CS Zent CS Wilson G Tricot S Jagannath D Siegel KR Desikan N Munshi D Bracy B Barlogie AW Butch 《Canadian Metallurgical Quarterly》1998,91(9):3518-3523
Multiple myeloma (MM) is usually characterized by production of a single serum monoclonal protein of constant isotype and light-chain restriction. Multiple Ig isotypes and isotype switches, which are rare in untreated patients, are reported to be more common in patients undergoing myeloablative therapy. These additional protein bands, detected by immunofixation electrophoresis (IFE), could be due to altered paraprotein production by the malignant plasma cell clone or oligoclonal Ig production during recovery of B-cell function after myeloablative therapy. We analyzed abnormal protein bands (APB), distinct from the presenting paraprotein, in 550 patients receiving high-dose therapy with autologous hematopoietic cell transplantation at a single institution. Fifty-five patients (10%) had APB, 48 had oligoclonal bands (OB), and 23 had an apparent isotype switch (IS) on IFE (16 had both OB and IS). Morphologic and flow cytometric examination of bone marrow in 17 patients with IS showed no evidence of a clonal plasma cell isotype switch. Patients with APB had significantly higher complete response to therapy (67% v 37%, P = .001). To assess the independent prognostic relevance of APB, a multivariate analysis was performed among 471 patients surviving at least 12 months from first transplant (all patients developing APB had done so by 12 months from first transplant). APB (in 50 patients) was a favorable feature for both event-free (rank 3, P = .004) and overall survival (rank 3, P = .0005). We propose that OB and IS are likely to be due to recovery of Ig production rather than alterations in the biology of the malignant plasma cell clone. 相似文献
38.
GL DeNardo SJ DeNardo DS Goldstein LA Kroger KR Lamborn NB Levy JP McGahan Q Salako S Shen JP Lewis 《Canadian Metallurgical Quarterly》1998,16(10):3246-3256
PURPOSE: Lym-1, a monoclonal antibody that preferentially targets malignant lymphocytes, has induced remissions in patients with non-Hodgkin's lymphoma (NHL) when labeled with iodine 131 ((131)I). Based on the strategy of fractionating the total dose, this study was designed to define the maximum-tolerated dose (MTD) and efficacy of the first two, of a maximum of four, doses of (131)I-Lym-1 given 4 weeks apart. Additionally, toxicity and radiation dosimetry were assessed. MATERIALS AND METHODS: Twenty patients with advanced NHL entered the study a total of 21 times. Thirteen (62%) of the 21 entries had diffuse large-cell histologies. All patients had disease resistant to standard therapy and had received a mean of four chemotherapy regimens. (131)I-Lym-1 was given after Lym-1 and (131)I was escalated in cohorts of patients from 40 to 100 mCi (1.5 to 3.7 GBq)/m2 body surface area. RESULTS: Mean radiation dose to the bone marrow from body and blood (131)I was 0.34 (range, 0. 1 6 to 0.63) rad/mCi (0.09 mGy/MBq; range, 0.04 to 0.17 mGy/ MBq). Dose-limiting toxicity was grade 3 to 4 thrombocytopenia with an MTD of 100 mCi/m2 (3.7 GBq/m2) for each of the first two doses of (131)I-Lym-1 given 4 weeks apart. Nonhematologic toxicities did not exceed grade 2 except for one instance of grade 3 hypotension. Ten (71 %) of 14 entries who received at least two doses of (131)I-Lym-1 therapy and 11 (52%) of 21 total entries responded. Seven of the responses were complete, with a mean duration of 14 months. All three entries in the 100 mCi/m2 (3.7 MBq/m2) cohort had complete remissions (CRs). All responders had at least a partial remission (PR) after the first therapy dose of (131)I-Lym-1. CONCLUSION: (131)I-Lym-1 induced durable remissions in patients with NHL resistant to chemotherapy and was associated with acceptable toxicity. The nonmyeloablative MTD for each of the first two doses of (131)I-Lym-1 was 100 mCi/m2 (total, 200 mCi/m2) (3.7 GBq/m2; total, 7.4 GBq/m2). 相似文献
39.
KR Korzekwa N Krishnamachary M Shou A Ogai RA Parise AE Rettie FJ Gonzalez TS Tracy 《Canadian Metallurgical Quarterly》1998,37(12):4137-4147
Some cytochrome P450 catalyzed reactions show atypical kinetics, and these kinetic processes can be grouped into five categories: activation, autoactivation, partial inhibition, substrate inhibition, and biphasic saturation curves. A two-site model in which the enzyme can bind two substrate molecules simultaneously is presented which can be used to describe all of these observed kinetic properties. Sigmoidal kinetic characteristics were observed for carbamazepine metabolism by CYP3A4 and naphthalene metabolism by CYPs 2B6, 2C8, 2C9, and 3A5 as well as dapsone metabolism by CYP2C9. Naphthalene metabolism by CYP3A4 and naproxen metabolism by CYP2C9 demonstrated nonhyperbolic enzyme kinetics suggestive of a low Km, low Vmax component for the first substrate molecule and a high Km, high Vmax component for the second substrate molecule. 7, 8-Benzoflavone activation of phenanthrene metabolism by CYP3A4 and dapsone activation of flurbiprofen and naproxen metabolism by CYP2C9 were also observed. Furthermore, partial inhibition of 7, 8-benzoflavone metabolism by phenanthrene was observed. These results demonstrate that various P450 isoforms may exhibit atypical enzyme kinetics depending on the substrate(s) employed and that these results may be explained by a model which includes simultaneous binding of two substrate molecules in the active site. 相似文献
40.
RL Murkofsky G Dangas JA Diamond D Mehta A Schaffer JA Ambrose 《Canadian Metallurgical Quarterly》1998,32(2):476-482
OBJECTIVE: We sought to determine whether a prolonged QRS-interval duration is associated with decreased left ventricular (LV) systolic function. BACKGROUND: The 12-lead electrocardiogram (ECG) is a routine test for suspected cardiac disease. Although several scoring systems have been devised to estimate LV systolic function, no studies have examined the direct relationship between QRS duration alone and LV systolic function. METHODS: We analyzed the standard 12-lead surface ECG of 270 consecutive patients, referred for radionuclide ventriculography. Patients (n = 44) with bundle branch blocks, atrial flutter or fibrillation, pacemaker rhythm, recent myocardial infarction or bypass surgery, and patients on antiarrhythmic drugs were excluded. In the remaining patients (n = 226), we correlated the QRS duration on standard resting ECG, and the resting LV ejection fraction (EF), end-systolic and end-diastolic counts (ESC and EDC, respectively; LV volume indices), as obtained by radionuclide angiography. We used a multivariate analysis to identify independent predictors of reduced ventricular function entering QRS duration, the previously described R-wave score and clinical variables in our model. RESULTS: The QRS duration in the abnormal EF group was significantly longer than in the normal EF group (0.102 vs. 0.091 s, p < 0.0001). A QRS duration >0.10 s was highly specific (83.6%), but modestly sensitive (43.8%), for the prediction of abnormal EF. Furthermore, an abnormal EF was predicted with incrementally increased specificity (83.6% to 99.3%) and a corresponding decrease in sensitivity (43.8% to 13.8%) for each 0.01-s increase in the definition of prolonged QRS (from >0.10 to >0.12 s). Accordingly, the positive likelihood ratio for the prediction of decreased LV function was increased from 2.67 to 19.7 as the definition of prolonged QRS duration was increased from >0.10 to >0.12 s. In the multivariate analysis, a prolonged QRS duration and a low R-wave score were the only independent predictors of decreased LV systolic function. CONCLUSIONS: Prolonged QRS duration (>0.10 s) obtained from a standard resting 12-lead ECG is a specific, but relatively insensitive indicator of decreased LV systolic function. Further prolongation of the QRS had a higher specificity for decreased LV EF and a higher positive likelihood ratio for predicting abnormal LV EF. 相似文献