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1.
We describe a decision support system to distinguish among hematology cases directly from microscopic specimens. The system uses an image database containing digitized specimens from normal and four different hematologic malignancies. Initially, the nuclei and cytoplasmic components of the specimens are segmented using a robust color gradient vector flow active contour model. Using a few cell images from each class, the basic texture elements (textons) for the nuclei and cytoplasm are learned, and the cells are represented through texton histograms. We propose to use support vector machines on the texton histogram based cell representation and achieve major improvement over the commonly used classification methods in texture research. Experiments with 3,691 cell images from 105 patients which originated from four different hospitals indicate more than 84% classification performance for individual cells and 89% for case based classification for the five class problem.
Oncel TuzelEmail:
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2.
The black‐colored pottery slips produced in Athens from the 6th to 4th centuries B.C., had a consistent composition achieved through processing and refinement of raw clay. Little direct evidence has been established as to what were these refinement methods. To better understand how the slip material was prepared, the major and trace elemental compositions of 19 slips from different ceramic vessels and their corresponding bodies of Athenian red‐figure and black‐figure vases were determined using laser ablation inductively coupled plasma mass spectrometry (LA‐ICPMS). Notably higher Zn concentrations were found in the slips (271–1959 ppm) than in their corresponding body ceramics (<361 ppm). The Zn concentrations in the slips were also found to be above the natural background for typical clay (between 10 and 300 ppm) suggesting an unintentional anthropogenic enrichment of this metal. Based on the abnormally high Zn content of the slip, it is speculated that the clay was treated using vitriol (concentrated acid mine runoff which is rich in Zn), to induce flocculation and remove carbonate mineral phases from the raw material that, if present, would prevent the slip from vitrifying. This same signature of elevated levels of Zn with a corresponding Ce anomaly is also observed for black glosses produced in Corinthian and Etrurian (Italy) workshops indicating that these trace element signatures were imparted to the material by means of shared methods of manufacturing instead of being indicative of a single unique source for this material.  相似文献   
3.
Dual phase oxide membranes have shown promising hydrogen permeation fluxes in syngas applications due to their high mixed proton electron conduction (MPEC). However, the conductivity of grain boundaries can be many orders of magnitude lower than that of the bulk and so limits the total conductivity and hydrogen permeation. In this study, the three-dimensional nanoscale oxygen and cation distributions around grain and phase boundaries in a BaCe0.8Y0.2O3-δ-Ce0.8Y0.2O2-δ (BCY-YDC) membrane were quantified by atom probe tomography (APT) and related to average grain boundary conductivity measured by electrochemical impedance spectroscopy (EIS). Segregation varied among the general high-angle grain boundaries analyzed, but no trend from orientation analysis was determined. Correlative APT and electron energy loss spectroscopy (EELS) of one YDC grain boundary revealed composition and cerium valence information, respectively, allowing for the determination of vacancies at the grain boundary. While a specific MPEC membrane is characterized, the results are relevant to proton and electron conduction in a number of technologically important ceramics.  相似文献   
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A major roadblock preventing the widespread use of casting simulation technology is the intensive effort required by a highly skilled-professional to construct a finite-element model. To address this situation, this article proposes an integrated-model construction procedure that reduces model construction time for a typical aeropropulsion component from two weeks to two days. It also describes another step toward the accurate and practical prediction of the coating process through coupled heat transfer, fluid flow, and stress calculation.  相似文献   
6.
Botulinum neurotoxin (BoNT) types A and B are Zn2+-requiring endoproteases which potently block neurotransmitter release by cleavage of a 25-kDa synaptosomal-associated protein (SNAP-25) and synaptobrevin, respectively. Synaptobrevin is important for the exocystosis of catecholamines from dense-core granules and evidence is presented here for the involvement of SNAP-25 in this process in neuroendocrine cells. The effects of BoNT/A and BoNT/B on regulated secretion were compared in intact bovine chromaffin cells to investigate the consequences of cleavage of the different targets. Catecholamine secretion elicited by Ba2+, by elevated K+ concentrations or by nicotine was prevented by each toxin. A very good correlation was observed between the extents of SNAP-25 cleavage or synaptobrevin cleavage and inhibition of secretion by BoNT/A or BoNT/B, respectively, which indicates the importance of SNAP-25 and synaptobrevin in regulated exocytosis. Despite truncation of almost the entire SNAP-25 pool by exposure of the cells to BoNT/A, a residual fraction of secretion persisted that was induced by 20microM Ca2+ (and to a lesser extent by 1 mM Ba2+) following permeabilisation. Addition of more BoNT/A failed to reduce this level of secretion. Inclusion of Mg.ATP, which greatly enhanced secretion from permeabilised cells, was required for Ca2+-stimulated or Ba2+-stimulated BoNT/A-resistant secretion. Furthermore, synaptobrevin is essential for this response because the response was not observed in BoNT/B treated cells. In view of the ability of BoNT/E to abolish secretion from permeabilised cells and to delete 26 amino acids from the C-terminus of SNAP-25, it can be deduced that cleavage of only nine residues by BoNT/A does not prevent the resultant truncated form exhibiting attenuated activity under the conditions created by permeabilisation. This identification of a novel component of secretion from permeabilised cells should facilitate investigation of the functional interaction of SNAP-25 with other proteins involved in regulated exocytosis.  相似文献   
7.
In a 48-year-old Japanese man there was an uncontrollable and recurrent bleeding from a gastric ulcer and laparoscopic surgery was done. Two cannulae were placed in the gastric cavity through the abdominal wall and suture ligation of the bleeding vessel at the posterior wall of the stomach was done under video-visual control with endoscopic guidance. The bleeding ceased, complications were nil, and he remains well. This article reports on surgery done to repair uncontrollable, recurrent bleeding from a gastric ulcer. Two cannulae were placed in the gastric cavity through the abdominal wall and suture of the vessel at the posterior wall of the stomach was done with videovisual control and endoscopic guidance. This approach is concluded to have supplied minimal-access surgery, cost effectiveness, early discharge, less pain, and doctor-patient satisfaction.  相似文献   
8.
Objective: Intimate partner violence (IPV) is a serious health concern, but little is known about prevalence of IPV in the armed forces, as military members cope with the pressures of long-standing operations. Furthermore, previous prevalence studies have been plagued by definitional issues; most studies have focused on acts of aggression without consideration of impact (clinically significant [CS] IPV). This is the first large-scale study to examine prevalences of IPV, CS-IPV, and clinically significant emotional abuse (CS-EA) for men and women. Method: A United States Air Force-wide anonymous survey was administered across 82 bases in 2006 (N = 42,744) to assess IPV, CS-IPV, and CS-EA. Results: The adjusted prevalence of CS-IPV perpetration was 4.66% for men and 3.54% for women. Prevalences of IPV perpetration were 12.90% for men and 15.14% for women. CS-EA victimization was 6.00% for men and 8.50% for women. Sociodemographic differences in risk for violence were found for gender, race/ethnicity, pay grade, religious faith, marital status, and career type even after controlling for other demographic variables. Conclusions: Partner maltreatment is widespread in military (and civilian) samples. Men were more likely to perpetrate CS-IPV, whereas women were more likely to perpetrate IPV. Specific demographic risk factors were identified for different types of partner maltreatment (e.g., lower rank predicted higher risk for both perpetration and victimization across men and women). Other sociodemographic differences varied across severity (IPV vs. CS-IPV) and across gender. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
9.
Between 1995 and 2008, Thailand’s energy efficiency programs produced an estimated total of 8,369 GWh/year energy savings and 1,471 MW avoided peak power. Despite these impressive saving figures, relatively little future scenario analysis is available to policy makers. Before the 2008 global financial crisis, electricity planners forecasted 5–6% long-term increases in demand. We explored options for efficiency improvements in Thailand’s residential sector, which consumes more than 20% of Thailand’s total electricity consumption of 150 TWh/year. We constructed baseline and efficient scenarios for the period 2006–2026, for air conditioners, refrigerators, fans, rice cookers, and compact fluorescent light bulbs. We drew on an appliance database maintained by Electricity Generating Authority of Thailand’s voluntary labeling program. For the five appliances modeled, the efficiency scenario results in total savings of 12% of baseline consumption after 10 years and 29% of baseline after 20 years. Approximately 80% of savings come from more stringent standards for air conditioners, including phasing out unregulated air conditioner sales within 6 years. Shifting appliance efficiency standards to current best-in-market levels within 6 years produces additional savings. We discuss institutional aspects of energy planning in Thailand that thus far have limited the consideration of energy efficiency as a high-priority resource.  相似文献   
10.
The intermediate phase involved in the production of ferroelectric material SrBi2Ta2O9 has a fluorite structure. If the structure of the intermediate phase were ideal, all the metal ions would have identical cubic oxygen environments. However, the tantalum ions are much smaller than the strontium and bismuth ions which could result in local deviations from the original structure. We present results of X-ray absorption spectroscopy studies which indicate the local tantalum atomic environments for the intermediate fluorite phase and the ferroelectric final Aurivillius phase material, a layer-structure perovskite. For both phases NEXAFS studies indicated very similar electronic structures at the tantalum sites. The EXAFS analysis revealed local structural information and indicated that the intermediate phase has a defect fluorite structure with the oxygen environment for the tantalum being related to that of the TaO6 octahedra of the final phase material.  相似文献   
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