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1.
Within the reactive oxygen species (ROS) generated by cellular metabolisms, hydroxyl radicals (HO) play an important role, being the most aggressive towards biomolecules. The reactions of HO with methionine residues (Met) in peptides and proteins have been intensively studied, but some fundamental aspects remain unsolved. In the present study we examined the biomimetic model made of Ac-Met-OMe, as the simplest model peptide backbone, and of HO generated by ionizing radiation in aqueous solutions under anoxic conditions. We performed the identification and quantification of transient species by pulse radiolysis and of final products by LC-MS and high-resolution MS/MS after γ-radiolysis. By parallel photochemical experiments, using 3-carboxybenzophenone (CB) triplet with the model peptide, we compared the outcomes in terms of short-lived intermediates and stable product identification. The result is a detailed mechanistic scheme of Met oxidation by HO, and by CB triplets allowed for assigning transient species to the pathways of products formation.  相似文献   
2.
Zusammenfassung Nach der Analyse von 35 Kotproben wird ein Beitrag zur Ernährung des Wolfes in Polen geliefert. Eine eigene Einteilung der ausgewählten Komponenten ist dabei zugrunde gelegt. Die Ergebnisse werden in den Tabellen 1 bis 4 dargestellt. Den höchsten Prozentanteil hat als Beutetier das Rehwild. In der Diskussion wird an Hand des Vergleiches in Tab. 5 Übereinstimmung zu den amerikanisch-kanadischen Untersuchungen aufgezeigt, deren Autoren dieselbe Methode verwandten.
Summmary Following the analysis of 35 samples of droppings, this paper contributes to the knowledge of the diet of the wolf in Poland. The diet issclassified on the components of the droppings, and the results are represented in Tables 1 to 4. The roe deer forms the highest percentage of the prey. On the basis of the comparison made in Table 5, the discussion comes to the same conclusions as American and Canadian studies, whose authors used the same methods.

Résumé Une analyse de 35 échantillons de matières fécales permet une meilleure connaissance de l'alimentation du Loup en Pologne. Pour le dépouillement de cette analyse, il est fait appel à un mode de présentation particulier des composants choisis. Les résultats figurent aux Tableaux 1 à 4. Parmi les proies du Loup, le Chevreuil constitue l'espèce la mieux représentée. Dans la discussion, on se réfère au Tableau 5 pour relever les similitudes de ces résultats avec ceux de recherches américaines et canadiennes pour lesquelles les auteurs ont fait usage de la même méthode.
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3.
A model of multiservice network architecture (M-architecture) is presented. An attempt is made to describe the traffic management and control schemes in a systematic way. The basic concepts are developed, and examples are given that indicate how the proposed framework can be used to solve multiplexing, routing, and flow control problems in the ISDN. The emphasis is on the traffic control schemes. The M-architecture can be regarded as either a reference architecture for future multiservice networks or an abstract model of traffic management and control in currently used networks  相似文献   
4.
Plasma viscosity is determined by various macromolecules, eg, fibrinogen, immunoglobulins, and lipoproteins. It may therefore reflect several aspects involved in cardiovascular diseases, including the effects of classic risk factors, hemostatic disturbances, and inflammation. We examined the association of plasma viscosity with the incidence of a first major coronary heart disease event (CHD; fatal and nonfatal myocardial infarction and cardiac death; n=50) in 933 men aged 45 to 64 years of the MONICA project of Augsburg, Germany. The incidence rate was 7.23 per 1000 person-years (95% confidence interval [CI], 5.37 to 9.53), and the subjects were followed up for 8 years. All suspected cases of an incident CHD event were classified according to the MONICA protocol. There was a positive and statistically significant unadjusted relationship between plasma viscosity and the incidence of CHD. The relative risk of CHD events associated with a 1-SD increase in plasma viscosity (0.070 mPa x s) was 1.60 (95% CI, 1.25 to 2.03). After adjustment for age, total cholesterol, high density lipoprotein cholesterol, smoking, blood pressure, and body mass index, the relative risk was reduced only moderately (1.42; 95% CI, 1.09 to 1.86). The relative risk of CHD events for men in the highest quintile of the plasma viscosity distribution in comparison with the lowest quintile was 3.31 (95% CI, 1.19 to 9.25) after adjustment for the aforementioned variables. A large proportion of events (40%) occurred among men in the highest quintile. These findings suggest that plasma viscosity may have considerable potential to identify subjects at risk for CHD events.  相似文献   
5.
Discrete- time stochastic models of sequential traffic records in telephone networks are considered. They appear to be well suited for a use of the Kaiman filter. A version of the filtering algorithm is adopted to deal with traffic fluctuations. The overall approach is tested against the real data gathered by the supervisor of the French toll network. The adaptive traffic estimator is inserted into a simulator of a testbed network operated in the urban zone of Paris. The traffic estimations provided by the filter are used to decide an overflow hierarchy.  相似文献   
6.
The impact of past policies and the nature of the existing system is assessed. Present demand and services are discussed. The role of international financing and participation is examined. Barriers to development are identified  相似文献   
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8.
In designing SAW dispersive delay lines (DDLs), one usually applies dispersive interdigital transducers with electrode spacing varying according to the frequency-delay time relation of the delay line impulse response. A new method is proposed in the letter, in which a DDL is treated as a bandpass filter with a nonlinear phase response. Such a filter can be synthesised with an IDT having periodic electrodes with apodisation. The experimental result is ?40 dB of sidelobe level obtained in a system of two DDLs, one of which is Hamming-weighted.  相似文献   
9.
We present results of early validation studies using retrieved atmospheric profiles from the Earth Observing System Microwave Limb Sounder (MLS) instrument on the Aura satellite. "Global" results are presented for MLS measurements of atmospheric temperature, ozone, water vapor, hydrogen chloride, nitrous oxide, nitric acid, and carbon monoxide, with a focus on the January-March 2005 time period. These global comparisons are made using long-standing global satellites and meteorological datasets, as well as some measurements from more recently launched satellites. Comparisons of MLS data with measurements from the Ft. Sumner, NM, September 2004 balloon flights are also presented. Overall, good agreement is obtained, often within 5% to 10%, but we point out certain issues to resolve and some larger systematic differences; some artifacts in the first publicly released MLS (version 1.5) dataset are noted. We comment briefly on future plans for validation and software improvements.  相似文献   
10.
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