The SwitchWare active network architecture

Active networks must balance the flexibility of a programmable network infrastructure against the safety and security requirements inherent in sharing that infrastructure. Furthermore, this balance must be achieved while maintaining the usability of the network. The SwitchWare active network architecture is a novel approach to achieving this balance using three layers: active packets, which contain mobile programs that replace traditional packets; active extensions, which provide services on the network elements and can be dynamically loaded; and a secure active router infrastructure, which forms a high-integrity base on which the security of the other layers depends. In addition to integrity checking and cryptography-based authentication, security in our architecture depends heavily on verification techniques from programming languages, such as strong type checking     

1/f Spin noise and a single spin detection with STM

We propose a novel mechanism for single spin detection based on the 1/f spin current noise. We postulate that the 1/f spin noise for the tunneling current is similar to the ubiquitous 1/f noise in magnetic systems. Magnetic coupling between tunneling electrons and localized spin S then leads to the peak at Larmor frequency in the power spectrum of the electric current fluctuations I²_ω. The elevated noise in the current spectrum will be spatially localized near the magnetic site. The difference in the power spectra taken at the Larmor frequency and elsewhere would reveal the peak in the spectrum. We argue that the signal-to-noise ratio for this mechanism is on the order of one. In addition, we discuss the asymmetric line shapes observed regularly with this measurement. We show that such line shapes are in accordance with the random sampling done with the tunneling electrons. Yet this predicts a line width at least one order of magnitude larger than observed experimentally, which is likely to be due to electrostatic repulsion between the tunneling electrons and temporal correlations in the tunneling process.     

Texture Evolution in Graphite-Like Phases Recrystallizing under External Stress

It has been observed that the texture axis of graphite-like boron nitride is reoriented by recrystallization under pressure. The observed effect is due to the compression conditions for the anisotropic phase deviating from hydrostatic.     

Efficiency of naphthalene biodegradation by Pseudomonas putida G7 in soil

The efficiency of naphthalene degradation by Pseudomonas putida G7 in soil was assessed using a mathematical model. The number of microorganisms and the concentration of naphthalene in soil samples were monitored. The feasibility of a spectrofluorometric method for naphthalene assay in soil samples was compared with high pressure liquid chromatography. A proposed mathematical model described the growth of the naphthalene‐degrading strains and the consumption of substrates (naphthalene, naphthalene degradation intermediates and soil organic substances) in soil. To describe the growth kinetics of microorganisms having high affinity to substrates with low solubility, two differential equations with substrate exponent 2/3 were proposed. These equations were used to describe utilization of soil organic matter. The model parameters characterize the growth rates for different substrates and respective yield coefficients, specific bacterial death and adaptation rates, and also the rates of PAHs degradation and evaporation. These characteristics can be used in choosing the bacterial strains for biopreparations and efficient clean‐up biotechnology of polluted soils. Copyright © 2004 Society of Chemical Industry     

Effect of Salt Stress on the Expression and Promoter Methylation of the Genes Encoding the Mitochondrial and Cytosolic Forms of Aconitase and Fumarase in Maize

The influence of salt stress on gene expression, promoter methylation, and enzymatic activity of the mitochondrial and cytosolic forms of aconitase and fumarase has been investigated in maize (Zea mays L.) seedlings. The incubation of maize seedlings in 150-mM NaCl solution resulted in a several-fold increase of the mitochondrial activities of aconitase and fumarase that peaked at 6 h of NaCl treatment, while the cytosolic activity of aconitase and fumarase decreased. This corresponded to the decrease in promoter methylation of the genes Aco1 and Fum1 encoding the mitochondrial forms of these enzymes and the increase in promoter methylation of the genes Aco2 and Fum2 encoding the cytosolic forms. The pattern of expression of the genes encoding the mitochondrial forms of aconitase and fumarase corresponded to the profile of the increase of the stress marker gene ZmCOI6.1. It is concluded that the mitochondrial and cytosolic forms of aconitase and fumarase are regulated via the epigenetic mechanism of promoter methylation of their genes in the opposite ways in response to salt stress. The role of the mitochondrial isoforms of aconitase and fumarase in the elevation of respiration under salt stress is discussed.     

The First Professional Degree: A Historic Opportunity

Historically, ASCE has worked to develop civil engineering (CE) education to ensure that the profession is continuously strengthened. Based on recent events, ASCE is poised to lead CE education into the twenty-first century. Of specific interest in this regard is the recent support shown by the Board of Direction for the master's as the first professional degree (FPD) for CE practice. To understand the ramifications of the board's policy statement, it is necessary to grasp the evolution of the FPD concept as well as undergraduate engineering curricular reform in general. Examining the shape of past debate opens a window onto the board's historic policy statement, which in turn helps illuminate the future course of action. Moreover, the writers contend that significant educational reform is necessary for CE to confront the changing, competitive global marketplace. Accordingly, three possible models to implement the FPD are explored: (1) Current master's degree programs; (2) 150-credit hour requirement used by accountancy; and (3) professional school.     

Keine Leibesvisitation unter Videobeobachtung

Ohne Zusammenfassung Dr. Alexander Dix, LL.M. Berliner Beauftragter für Datenschutz und Informationsfreiheit