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Gilbert Held 《International Journal of Network Management》2003,13(2):163-169
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Gilbert Held 《International Journal of Network Management》2006,16(5):375-379
One of the software programs we take for granted is antivirus software. Perhaps part of the reason for not being excited about protecting our computers resides in the fact that most PCs marketed over the past few years are bundled with an antivirus solution. When you initialize the computer you also start your virus protection program, which will often provide you with only a short period of protection before pop‐up messages appear reminding you to renew your antivirus program license to ensure your protection is up to date. What is more than likely never mentioned to consumers is the fact that the antivirus software bundled with your computer was positioned there due to the software vendor paying the computer manufacturer a fee. While most third‐party software placed on new computers must pass a certain level of quality assurance, the computer manufacturer is more interested in the placement fee than whether the software is the best for the purchaser of the computer. Thus, one of the things we should do when our antivirus software license expires, if not sooner, is to look at other possible solutions beyond the software bundled with the computer. One such antivirus product that warrants our attention and which is the focus of this column is ESET's NOD32 for Windows antivirus solution, which was originally developed in Slovakia. 相似文献
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The curing of diglycidyl ether of bisphenol A (DGEBA) with 2,6-dimethylol-p-cresol modified by hexahydrophthalic acid anhydride was investigated and compared with the analogous in situ curing of DGEBA, hexahydrophthalic acid anhydride and 2,6-dimethylol-p-cresol. The chemical reactions were investigated by means of titration and different spectroscopic and chromatographic methods. It was examined whether the less complicated and therefore cheaper in situ reaction delivers postcured products with equal or better properties. Furthermore, it was investigated whether the results are similar using technical phenolic hardeners. 相似文献
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C Held P Hjemdahl N Rehnqvist NH Wallén I Bj?rkander SV Eriksson L Forslund B Wiman 《Canadian Metallurgical Quarterly》1997,95(10):2380-2386
BACKGROUND: Disturbed fibrinolytic function may influence the progression of coronary atherosclerosis and contribute to thrombotic cardiovascular (CV) events. METHODS AND RESULTS: In the Angina Prognosis Study in Stockholm (APSIS), patients with stable angina pectoris were studied prospectively during double-blind treatment with metoprolol or verapamil. Various measures of fibrinolytic function were studied in 631 (of 809) patients. During a median follow-up time of 3.2 years (2132 patient-years), 32 patients suffered a CV death, 21 had a nonfatal myocardial infarction (MI), and 77 underwent revascularization. Plasma levels of tissue plasminogen activator (TPA) activity and antigen (ag), plasminogen activator inhibitor (PAI-1) activity at test, and TPA responses to exercise were determined at baseline and after 1 month's treatment and were related to subsequent fatal and nonfatal CV events. Univariate Cox regression analysis revealed that elevated levels of TPA-ag at rest (P < .05), high PAI-1 activity (P < .05), and low TPA-ag responses to exercise (P < .05) were associated with increased risk of subsequent CV death. After adjustment for baseline risk factors, TPA-ag independently predicted CV death or MI. In addition, PAI-1 activity independently predicted CV death or MI in male patients. Verapamil treatment was associated with a 10% decrease of TPA-ag levels and metoprolol treatment with a 2% increase (P < .001 for treatment difference). CONCLUSIONS: Plasma TPA-ag levels at rest, and among male patients PAI-1 activity as well, independently predict subsequent CV death or MI in patients with stable angina pectoris. 相似文献
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Head-related transfer functions (HRTFs) were used to create spatialized stimuli for presentation through earphones. Subjects performed forced-choice, identification tests during which allowed response directions were indicated visually. In each experimental session, subjects were first presented with auditory stimuli in which the stimulus HRTFs corresponded to the allowed response directions. The correspondence between the HRTFs used to generate the stimuli and the directions was then changed so that response directions no longer corresponded to the HRTFs in the natural way. Feedback was used to train subjects as to which spatial cues corresponded to which of the allowed responses. Finally, the normal correspondence between direction and HRTFs was reinstated. This basic experimental paradigm was used to explore the effects of the type of feedback provided, the complexity of the stimulated acoustic scene, the number of allowed response positions, and the magnitude of the HRTF transformation subjects had to learn. Data showed that (1) although subjects may not adapt completely to a new relationship between physical stimuli and direction, response bias decreases substantially with training, and (2) the ability to resolve different HRTFs depends both on the stimuli presented and on the state of adaptation of the subject. 相似文献
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Manfred Edelhäuser und Karl-Gustav Bergner 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,184(3):189-194
Zusammenfassung Die Isolierung der Saccharase (E.C. 3.2.1.20) aus den Proteinkonzentraten von Raps-, Tannen- und Zuckerfütterungshonig wird beschrieben. Die Abtrennung von anderen Enzymen, insbesondere von saurer Phosphatase gelingt durch hydrophobe Wechselwirkungschromatographie, von inerten Proteinen durch Gelfiltration. Im Zusammenhang damit wird das Verhalten des Enzyms bei der Chromatographie an Anionenaustauschern, an Hydroxylapatit und an immobilisiertem Weizenkeimlectin untersucht. Dabei ergab sich am Lectin-Gel eine Trennung in zwei multiple Formen.Die Saccharase aus allen drei Honigsorten verhielt sich einheitlich, woraus zu schließen ist, daß sie ausschließlich von der Biene stammt. Ihre Molekül masse wurde gelchromatographisch zu 57000 ermittelt.
The proteins of honeyVIII. Honey sucrase, isolation, chromatographic behaviour and properties
Summary The isolation of the honey sucrase (E.C. 3.2.1.20) from rape- and fir-honey as well as from honey obtained after sugar feeding is described. The separation from other honey enzymes especially from acid phosphatase succeded by reversed phase chromatography. Separation of other, non-active proteins was accomplished by gel permeation chromatography. The behaviour of the honey sucrase upon chromatography on anion exchangers, on hydroxylapatite and wheat germ lectin was investigated. No differences were found between the sucrases of the three honeys.The molecular weight was determined at 57 000. By affinity chromatography with wheat germ lectin the enzyme could be separated into two multiple forms.相似文献
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