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71.
S Hassid C Decaestecker C Hermans I Salmon JL Pasteels A Danguy R Kiss 《Canadian Metallurgical Quarterly》1997,106(12):1043-1051
The aim of this study is to present a new classification of nasal polyps. This classification is based both on morphologic criteria relating to morphonuclear features from isolated Feulgen-stained nuclei and on glycohistochemical characteristics from histologic slides submitted to three lectins (peanut, wheat germ, and gorse seed agglutinins) and one neoglycoconjugate glycohistochemical stain. While the morphonuclear features (including 30 variables) relate essentially to chromatin pattern, the glycohistochemical stains (including 16 variables) are linked to the presence of specific carbohydrate moieties in cell membranes and cytoplasm. Forty-nine nasal polyps, including single polyps, diffuse polyposis, cystic fibrosis-related polyposis, and aspirin idiosyncracy-related polyposis associated with asthma, were thus characterized. All the variables were obtained quantitatively by means of computer-assisted microscopy. Two complementary methods of data classification were used to determine the actual diagnostic value contributed by each quantitative variable, namely, discriminant analysis, which forms part of multifactorial statistical analysis, and the decision tree technique, which is an artificial intelligence-related algorithm. The data so obtained show that our morphologic classification of nasal polyps fits in with the classification of nasal polyps defined on the basis of clinical criteria. 相似文献
72.
Here we make the hypothesis that the determination of the concentration of lung specific secretory proteins in serum or pneumoproteinaemia could be used in the evaluation of lung disorders with a similar utility as proteinuria in kidney diseases involving the glomeruli. Human and experimental data indicate that comparable structural and functional features govern the passage of proteins across the lung epithelium/blood barrier and the glomerular filter. The concentrations in serum of some lung-specific secretory proteins, such as the bronchiolar Clara cell 16 kDa protein (CC16) and alveolar surfactant-associated proteins A and B (SP-A and SP-B, respectively), might be used to assess the integrity of the bronchoalveolar/blood barrier known to be disrupted in many lung disorders. In addition, if this barrier is intact or slightly compromised, these proteins might serve as peripheral markers to detect changes in secretory epithelial cells in the lung. 相似文献
73.
74.
蔡妮娜 《艺术与设计.数码设计》2007,(1)
本文通过对品牌战略和文化及其二者关系的分析来说明文化的介入在企业竞争中所起到的重要作用。文化的介入使品牌战略更具包容力,使企业更具凝聚力和竞争力。只有依靠优秀的文化,企业才能像常青藤一样生机盎然、充满活力。 相似文献
75.
Frese Michael; Krauss Stefanie I.; Keith Nina; Escher Susanne; Grabarkiewicz Rafal; Luneng Siv Tonje; Heers Constanze; Unger Jens; Friedrich Christian 《Canadian Metallurgical Quarterly》2007,92(6):1481
A model of business success was developed with motivational resources (locus of control, self-efficacy, achievement motivation, and self-reported personal initiative) and cognitive resources (cognitive ability and human capital) as independent variables, business owners' elaborate and proactive planning as a mediator, and business size and growth as dependent variables. Three studies with a total of 408 African micro and small-scale business owners were conducted in South Africa, Zimbabwe, and Namibia. Structural equation analyses partially supported the hypotheses on the importance of psychological planning by the business owners. Elaborate and proactive planning was substantially related to business size and to an external evaluation of business success and was a (partial) mediator for the relationship between cognitive resources and business success. The model carries important implications for selection, training, and coaching of business owners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
The goal of this research is to study the elasto-plastic properties of La-Cr-O thin films deposited by RF-magnetron sputtering on stainless steel interconnect materials after annealing at high temperatures in air. Elastic modulus, hardness and yield pressure derived from nanoindentation data are reported for thin films in different structural states. The amorphous film has an estimated elastic modulus of 174 GPa. The moduli of annealed films are calculated to be 150, 185 and 120 GPa after annealing at 500 °C, 600 °C and 800 °C, respectively. The film annealed at 800 °C has the lowest hardness and is dramatically different from the other structural states due to formation of the nanoporosity. The amorphous film and the films annealed at 500 °C and 600 °C both have hardness of 14 GPa, which is close to the value estimated by modeling. 相似文献
77.
Quick Response (QR) codes are a type of 2D barcode that is becoming very popular, with several application possibilities. Since they can encode alphanumeric characters, a rich set of information can be made available through encoded URL addresses. In particular, QR codes could be used to aid visually impaired and blind people to access web based voice information systems and services, and autonomous robots to acquire context-relevant information. However, in order to be decoded, QR codes need to be properly framed, something that robots, visually impaired and blind people will not be able to do easily without guidance. Therefore, any application that aims assisting robots or visually impaired people must have the capability to detect QR codes and guide them to properly frame the code. A fast component-based two-stage approach for detecting QR codes in arbitrarily acquired images is proposed in this work. In the first stage, regular components present at three corners of the code are detected, and in the second stage geometrical restrictions among detected components are verified to confirm the presence of a code. Experimental results show a high detection rate, superior to 90 %, at a fast speed compatible with real-time applications. 相似文献
78.
Markus Schleburg Lars Christiansen Nina F. Thornhill Alexander Fay 《Journal of Process Control》2013,23(6):839-851
A process alarm arises when normal operation limits are exceeded and an alarm management system alerts the operator of a process plant. Due to the material, energy and information flow in a plant, single disturbances can cause multiple consequent alarm messages, and the alarm messages may overload the operator by presenting many redundant alarms. This undesired situation is called an ‘alarm flood’. In such situations, the operator might not be able to fulfil his required tasks to keep the plant within safe operation limits and to find the root cause of the disturbance. The aim of the work presented in this paper is to reduce the number of alerts presented to the operator. If alarms are related to one another, those alarms should be grouped and presented as one alarm problem. For the implementation of the concept, a software prototype has been developed to perform this reduction automatically. The analysis process starts with the alarm history which is a log containing all past alarm messages. This is combined with the plant topology of the controlled system and a set of rules. The rules describe typical interrelations between alarm messages which have a common cause. The combination of these three elements yields an effective alarm management strategy that can help plant owners and operators to comply with standards for alarm management such as ANSI/ISA 18.2 (2009) and EEMUA 191 (2007) which set limits on the number of alarms per unit time for an operator. The effectiveness of the approach is illustrated by two industrial examples where a significant reduction of alarms has been achieved. 相似文献
79.
Hand tools should be designed so that they are comfortable to use, fit the hand and are user-oriented. Six different manual, single-channel axial pipettes were evaluated for such objective outcomes as muscular activity, wrist postures and efficiency, as well as for subjective outcomes concerning self-assessed features of pipette usability and musculoskeletal strain. Ten experienced laboratory employees volunteered for the study. The results showed that light and short pipettes with better tool comfort resulted in reduced muscular activity and perceived musculoskeletal strain when they were compared with a long and heavy pipette. There were no differences in the efficiency between the different pipettes. Combining both the objective and subjective measures enabled a broader evaluation of product usability. The results of this study can be used both in product development and as information on which to base the purchase of new pipettes for laboratory work. 相似文献
80.
Recent 3D sketch tools produce networks of three‐space curves that suggest the contours of shapes. The shapes may be non‐manifold, closed three‐dimensional, open two‐dimensional, or mixed. We describe a system that automatically generates intuitively appealing piecewise‐smooth surfaces from such a curve network, and an intelligent user interface for modifying the automatically chosen surface patches. Both the automatic and the semi‐automatic parts of the system use a linear algebra representation of the set of surface patches to track the topology. On complicated inputs from ILoveSketch [ [BBS08] ], our system allows the user to build the desired surface with just a few mouse‐clicks. 相似文献