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71.
In order to effectively communicate information, the choice of representation is important. Ideally, a chosen representation will aid readers in making desired inferences. In this paper, we develop the theory of observation: what it means for one statement to be observable from another. Using observability, we give a formal characterization of the observational advantages of one representation of information over another. By considering observational advantages, people will be able to make better informed choices of representations of information. To demonstrate the benefit of observation and observational advantages, we apply these concepts to set theory and Euler diagrams. In particular, we can show that Euler diagrams have significant observational advantages over set theory. This formally justifies Larkin and Simon’s claim that “a diagram is (sometimes) worth ten thousand words”.  相似文献   
72.
73.
Cathepsin X is a lysosomal peptidase that is involved in tumour progression and represents a potential target for therapeutic interventions. In addition, it regulates important functions of immune cells and is implicated in the modulation of tumour cell–immune cell crosstalk. Selective cathepsin X inhibitors have been proposed as prospective antitumour agents to prevent cancer progression; however, their impact on the antitumour immune response has been overlooked. Previous studies indicate that the migration and adhesion of T cells and dendritic cells are affected by diminished cathepsin X activity. Meanwhile, the influence of cathepsin X inhibition on natural killer (NK) cell function has not yet been explored. Here, we examined the localization patterns of cathepsin X and the role of its inhibitors on the cytotoxicity of cell line NK-92, which is used for adoptive cellular immunotherapy in cancer patients. NK-92 cells depend on lymphocyte function-associated antigen 1 (LFA-1) to form stable immunoconjugates with target cells, providing, in this way, optimal cytotoxicity. Since LFA-1 is a substrate for cathepsin X activity in other types of cells, we hypothesized that cathepsin X could disturb the formation of NK-92 immunoconjugates. Thus, we employed cathepsin X reversible and irreversible inhibitors and evaluated their effects on the NK-92 cell interactions with target cells and on the NK-92 cell cytotoxicity. We show that cathepsin X inhibition does not impair stable conjugate formation or the lytic activity of NK-92 cells. Similarly, the conjugate formation between Jurkat T cells and target cells was not affected by cathepsin X activity. Unlike in previous migration and adhesion studies on T cells, in NK-92 cells cathepsin X was not co-localized with LFA-1 at the plasma membrane but was, rather, redistributed to the cytotoxic granules and secreted during degranulation.  相似文献   
74.
A simple manufacturing process based on screen-printing is crucial for a successful commercialization of dye-sensitized solar cells (DSSCs). We developed the sol–gel based TiO2 paste in such a way that solely a single step deposition is sufficient to realize a sponge-like structure of the layer assuring its high activity in DSSCs. For the first time the sol–gel based TiO2 paste was screen printed and tested in DSSC masterplates and PV mini-modules. Electroluminescence imaging of the mini-module proved layer homogeneity and no manufacturing defects. The conversion efficiency of the PV mini-module with the active area of 75 cm2 reaches 5.7% at STC.  相似文献   
75.
In this paper we present an investigation into whether and how decision procedures can be learnt and built automatically. Our approach consists of two stages. First, a refined brute-force search procedure applies exhaustively a set of given elementary methods to try to solve a corpus of conjectures generated by a stochastic context-free grammar. The successful proof traces are saved. In the second stage, a learning algorithm (by Jamnik et al.) tries to extract a required supermethod (i.e., decision procedure) from the given traces. In the paper, this technique is applied to elementary methods that encode the operations of the Fourier-Motzkin's decision procedure for Presburger arithmetic on rational numbers. The results of our experiment are encouraging.  相似文献   
76.
Direct esterification of citronellol and lauric acid catalyzed by immobilized lipase B from Candida antarctica was performed in supercritical carbon dioxide with different organic solvents and ionic liquids serving as co-solvents. The highest concentration of citronellol laurate after 1 h of reaction performance (3.95 mmol/g substrates) was obtained in SC CO2 with ethyl methylketone serving as a co-solvent. The optimal temperature and pressure for citronellol laurate synthesis in SC CO2/EMK medium was determined to be 60 °C and 10 MPa.  相似文献   
77.
The influence of cultivar and picking date on the phenolic content of walnut liqueur was investigated using HPLC with a PDA detector. Ten phenolic compounds, namely gallic, protocatechuic, ellagic, chlorogenic (5-caffeoylquinic), syringic, p-coumaric and sinapic acids, as well as (+)-catechin, 1,4-naphthoquinone and juglone were detected. The walnut liqueur under analysis was made of the cultivars ‘Franquette’ and ‘Elit’, on two sampling dates (June 30th and July 7th). A close interaction between cultivar and sampling date was noticed for most of the phenolics analyzed. The content levels of the main phenolic compounds under investigation were highest in ‘Franquette’ at the end of June and lowest in ‘Elit’ on the second or both sampling dates, except for syringic acid. A strong influence of cultivar choice and picking date was observed. The content levels of most phenolics were higher in liqueur prepared from the cultivar ‘Franquette’, than in ‘Elit’.  相似文献   
78.
Attic and household dusts from Pb‐polluted area were investigated using various analytical techniques for source apportionment and assessment of source contribution of metal‐bearing phases. Mineralogically, attic dust consists of gypsum, anhydrite, and metal‐bearing phases, while household dust comprises C‐bearing particles and only minor metal‐bearing phases. Sulfur isotope composition of sulfides and sulfates in attic dust shows that they result from past primary smelting of local sulfide ore, while those in household dust originate directly from local mine‐waste material. Pb isotope ratios show that Pb‐bearing phases in both dust types mostly originate from mining and primary smelting of local Pb‐ore. Individual metal‐bearing particles were apportioned by their composition, morphology, and mineralogy to phases from past Pb‐smelting, present‐day Pb‐recycling, and past mining/mine‐waste mechanical processing. Calculated source contribution of metal‐bearing phases to indoor dust showed that primary Pb‐smelting was important pollution source in the past, while active Pb‐recycling has contributed only negligible amount of material so far. However, material from mining/mine‐waste processing is an important currently active pollution source. Study demonstrated that simultaneous investigation of characteristics and isotopic composition of metal‐bearing phases in different indoor dust types serves as tool for assessment of source contribution of past and recent airborne metal pollution.  相似文献   
79.
Pumpkin seed oil press cake (PSOPC) is a by-product of pumpkin oil production, and after cold pressing, a significant amount of oil still remains in the press cake. The aim of this study was to investigate the possible use of PSOPC flour as a substitute for wheat flour in biscuit production and, consequently, for reducing shortening usage. Biscuits have been produced from composite blends of plain white flour and PSOPC flour in ratios 100:0, 80:20, 60:40 and 40:60, respectively. Shortening addition was gradually reduced depending on the PSOPC flour addition. Biscuit baking quality was determined by width, thickness, spread factor, volume and textural properties. Computer vision was used to evaluate biscuit colour, and sensory evaluation was conducted for colour, taste, texture and overall acceptance. Results showed that PSOPC flour decreased biscuit diameter, height and volume and also caused a softer texture of biscuit. PSOPC flour contributed to the greenish colour of biscuits and the pleasant taste of roasted pumpkin seed. PSOPC flour can be successfully used as a functional and nutritionally valuable substitute for wheat flour and shortening, even in quantities up to 60%, without significant deterioration of the technological quality of biscuits.  相似文献   
80.
BACKGROUND: Accurate prognosis in chronic heart failure has become increasingly important in assessing the efficacy of treatment and in appropriately allocating scarce resources for transplantation. Previous studies of severe heart failure have been limited by short follow-up periods and few deaths. OBJECTIVE: To establish clinical, hemodynamic, and cardiopulmonary exercise test determinants of survival in patients with heart failure. DESIGN: Retrospective study. SETTING: Hospital-based outpatient heart failure clinic. PARTICIPANTS: 644 patients referred for evaluation of heart failure over 10 years. MEASUREMENTS: Age, cause of heart failure, body surface area, cardiac index, ejection fraction, pulmonary capillary wedge pressure, left ventricular dimensions, watts achieved during exercise, heart rate, maximum systolic blood pressure, and oxygen uptake (VO2) at the ventilatory threshold and at peak exercise were measured at baseline. Univariate and multivariate analyses were done for clinical, hemodynamic, and exercise test predictors of death. A Cox hazards model was developed for time of death. RESULTS: During a mean follow-up period of 4 years, 187 patients (29%) died and 101 underwent transplantation. Actuarial 1-year and 5-year survival rates were 90.5% and 73.4%, respectively. Resting systolic blood pressure, watts achieved, peak VO2, VO2 at the ventilatory threshold, and peak heart rate were greater among survivors than among nonsurvivors. Cause of heart failure (coronary artery disease or cardiomyopathy) was a strong determinant of death (relative risk for coronary artery disease, 1.73; P< 0.01). By multivariate analysis, only peak VO2 was a significant predictor of death. Stratification of peak VO2 above and below 12, 14, and 16 mL/kg per minute demonstrated significant differences in risk for death, but each cut-point predicted risk to a similar degree. CONCLUSIONS: Peak VO2 outperforms clinical variables, right-heart catheterization data, exercise time, and other exercise test variables in predicting outcome in severe chronic heart failure. Direct measurement of VO2 should be included when clinical or surgical decisions are being made in patients referred for evaluation of heart failure or those considered for transplantation.  相似文献   
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