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641.
An innovated system is described which integrates data from heterogeneous multimedia domains. This general-purpose framework uses the concept of a `mediator' to efficiently support multimedia reasoning. The Media Abstraction Creation System (MACS) implements algorithms for creating or querying media abstractions, for relaxing queries, and for allowing incremental query modifications. We have also developed an integrated framework within which media data can be queried even when those queries need to access other (nonmedia) background data and software. Access to diverse, nonmedia databases is provided by the Heterogeneous Reasoning and Mediator System (Hermes) 相似文献
642.
An analysis of the relationship between the anatomic site of cutaneous melanoma, sun exposure, and phenotype was conducted in 355 women with histologically confirmed superficial-spreading melanoma and in 935 control subjects. The most frequent site for superficial-spreading melanoma was the leg. However, when major sun-related and phenotype risk factors were examined by site, risk ratios were lowest for melanomas that occurred on the leg. A history of frequent sunburns during elementary or high school, increased number of self-assessed large nevi, and blond hair were more strongly associated with melanoma sites other than the leg. Tumors on the trunk were more likely than tumors at other sites to be associated with histological evidence of a preexisting nevus. Results of this work indicate that associations between melanoma phenotypic factors may differ by anatomic site. 相似文献
643.
A study was performed to evaluate immediate changes in carotid artery blood flow after carotid endarterectomy using a Doppler ultrasonographic flowmeter. Forty-seven consecutive patients aged 49-78 (median 64) years with symptomatic internal carotid artery (ICA) stenosis underwent carotid endarterectomy. Volume flow, resistance and pulsatility index were measured in the common carotid artery (CCA) and ICA both before and after operation. ICA flow increased by 54 per cent (P < 0.01) and resistance decreased by 58 per cent (P = 0.01). CCA flow rose by 17 per cent (P = 0.1) and resistance fell by 21 per cent (P = 0.02). The pulsatility index did not change significantly. The Doppler ultrasonographic flowmeter offers a simple, non-invasive and convenient means of improving understanding of the immediate haemodynamic effects of carotid endarterectomy. It is useful in everyday practice to confirm the adequacy of endarterectomy, particularly in the absence of other methods of quality control. Duplex ultrasonography might still be necessary after surgery if the flowmeter does not demonstrate an increase in flow compared with the preoperative value. 相似文献
644.
645.
“Posh”这个词是用来表述优雅和时尚,内在魅力和翩翩的风度,贝尔城地区是西雅图的明珠,这个混凝土的丛林实现了新生活方式的起点和不同于主流的购物环境,提供的服务包括个性的服饰,各国美味,现代风格的俱乐部和家庭风格的咖啡,我的理想是在休息厅设计中实现这种豪华的味道,体现出高贵感受。 相似文献
646.
Steven W. Leman Paul L. Brink Blas Cabrera Astrid Tomada Betty Young Dennis S. Martínez-Galarce 《Journal of Low Temperature Physics》2008,151(1-2):40-45
We continue our development of a phonon-mediated distributed-TES X-ray detector. X-rays are absorbed in a large silicon or
germanium crystal, and the energy is read out by four distributed TESs. This design takes advantage of existing TES technology
while overcoming the difficulties of designing spatially large arrays. In this paper, we discuss three detector designs. First,
a silicon detector with 220 μm deep trenches through a 350 μm crystal. Second, a germanium detector with 275 μm deep trenches
through a 550 μm crystal. Finally another silicon detector with 330 μm deep trenches through a 350 μm crystal. We discuss
energy loss mechanisms in the detector and propose a reason for the energy resolution that we observe.
相似文献
647.
Papercraft models can serve as inexpensive prototypes in shape design applications. However, in making the models some geometric detail is necessarily lost, and artificial creases may be visible, thereby limiting the utility of these models. To compensate for these practical limitations, we introduce the use of printed patterns on papercraft models to enhance the perception of the shape they are intended to represent. We propose pattern generation schemes that modulate the sizes, directions, and densities of glyphs of patterns based on geometric attributes. We present a psychophysical experiment designed to explore the effect that printed patterns have on the perception of the papercraft model shapes. We find that models with printed patterns are perceived to represent the intended shape more accurately, and, further, that the type of printed pattern has an impact on the perceived shape. 相似文献
648.
Peter S. Kirk Theodore Koreckij Holly M. Nguyen Lisha G. Brown Linda A. Snyder Robert L. Vessella Eva Corey 《International journal of molecular sciences》2013,14(5):10483-10496
The C-C chemokine ligand 2 (CCL2) stimulates migration, proliferation, and invasion of prostate cancer (PCa) cells, and its signaling also plays a role in the activation of osteoclasts. Therefore targeting CCL2 signaling in regulation of tumor progression in bone metastases is an area of intense research. The objective of our study was to investigate the efficacy of CCL2 blockade by neutralizing antibodies to inhibit the growth of PCa in bone. We used a preclinical model of cancer growth in the bone in which PCa C4-2B cells were injected directly into murine tibiae. Animals were treated for ten weeks with neutralizing anti-CCL2 antibodies, docetaxel, or a combination of both, and then followed an additional nine weeks. CCL2 blockade inhibited the growth of PCa in bone, with even more pronounced inhibition in combination with docetaxel. CCL2 blockade also resulted in increases in bone mineral density. Furthermore, our results showed that the tumor inhibition lasted even after discontinuation of the treatment. Our data provide compelling evidence that CCL2 blockade slows PCa growth in bone, both alone and in combination with docetaxel. These results support the continued investigations of CCL2 blockade as a treatment for advanced metastatic PCa. 相似文献
649.
Double-cropping annual ryegrass and bermudagrass to reduce phosphorus levels in soil with history of poultry litter application 总被引:1,自引:0,他引:1
J. J. Read K. R. Sistani J. L. Oldham G. E. Brink 《Nutrient Cycling in Agroecosystems》2009,84(1):93-104
Long-term application of poultry litter may result in excessively high soil phosphorus (P). This field study determined the
potential of ‘Coastal’ bermudagrass overseeded with ‘Marshall’ annual ryegrass and harvested for hay to reduce the level of
Mehlich-3 extractable P (M3-P) that had accumulated in a Savannah soil due to a 30-year history of broiler litter application
to bermudagrass, as well as antecedent litter rates of 0, 4.48, 8.96, 17.9, and 35.8 Mg ha−1 in 1999–2001. Following the cessation of litter, the plots were overseeded in fall 2001–2003 and fertilized in summer with
268 kg N ha−1 as NH4NO3. Applying 8.96 Mg ha−1 litter significantly elevated M3-P in surface soil (0–15 cm depth) from about 183 to 263 mg kg−1. Annual dry matter (DM) yield and P uptake generally increased as litter rate increased up to 17.9 Mg ha−1. Analysis of M3-P at four sampling dates from October 2002 to April 2004 found no significant effect of forage system or
its interaction with litter rate, and levels in both systems decreased by about 25, 27, 22, 26, and 29% at the five litter
rates, respectively. Ryegrass–bermudagrass significantly increased DM yield and P uptake, but did not translate to reductions
in M3-P, as compared to bermudagrass winter fallow. With no further litter additions and five harvests per year, both forage
systems removed about 49 kg ha−1 P with a DM yield of 15 Mg ha−1 and reduced M3-P by about 26 mg kg−1 annually. Bermudagrass performance is important in the remediation of high soil P.
相似文献
J. J. ReadEmail: |
650.
Maud Brink 《Advanced Synthesis \u0026amp; Catalysis》1977,319(4):529-538
Some Stereochemical Aspects of the Reaction between Cyclohexylidene Acetaldehydes and Thiols The reaction between cyclohexylidene acetaldehyde, 4-methyl-cyclohexylidene acetaldehyde resp. 4-tert.-butylcyclohexylidene acetaldehyde and thioglycolic acid thioglycolic acid methylester, benzylthiol resp. isopropylthiol and catalytical amounts of conc. HCl gave 60% cyclohexylidene acetaldehyde dimercaptales 1 – 3 . In addition to these compounds i t was also obtained in 40% a mixture of 46% cis and 54% trans forms of the cyclohexane derivatives 4–9. Double magnetic non equivalent methylenic protons were found in the compounds 2a – 2c and 3a – 3c and double magnetic non equivalent geminal methyl groups in the compounds 2d and 3d . 4JH,H couplings were observed in 1–3. The reaction mechanisms of the formation of the compounds 4–9 as well as the 1H-n.m.r. spectra of the compounds 1–9 were discussed. 相似文献