A Critical Time for Ultra-Wide Band

Ultra-wideband (UWB) is a promising class of high-speed wireless communications applications that is projected to significantly change local and wide area network architectures. This article describes the technology, its probable application areas, the environmental forces that are constraining and enabling commercialization, and the prospects for short-term growth for UWB services. Commercial sale and distribution of UWB products has been approved, and widespread sale is expected by 2007

Quantum Chemistry of Electrode Processes. II. Higher Activation Energies

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69659/2/JCPSA6-45-2-761-2.pd

Quantum Chemistry of Electrode Processes. I. General Relations for Electron Exchange between Electrode and Electroactive Species under Equilibrium and Nonequilibrium Conditions

It is assumed in this paper that at the electrode—solution interface there is molecular order of the electroactive species resembling solid‐state order. Specifically, it is assumed that next to the electrode is a layer of adsorbed neutral solvent molecules which are also ligands coordinated to the ions found in the interface. The mechanism of electron transfer from the electrode to the ion or the reverse from the ion to the electrode is assumed initially to involve a transition from either the electrode or the ion to the solvent molecule. This is followed by a transition of the electron from the solvent molecule to either the ion or the electrode. The two transitions involved in the net transfer of an electron across the interface are considered analogous to the charge‐transfer mechanism of spectroscopy. The wavefunctions representing the system at the interface are then of the same form as the charge‐transfer wavefunctions given by Mulliken.By considering the radiationless transition probabilities for the electron transitions in the interface system at the electrode, it is found that the usual current expressions result. By imposing the condition of zero net current at equilibrium the Nernst equation results. By further considering the polarization of the electrode under nonequilibrium conditions as a perturbation of the energy levels of the system, it is found that with the proper identification of terms the current expression for the polarized electrode results.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71116/2/JCPSA6-43-9-3291-1.pd

Sub-picosecond temporal resolution of anomalous Hall currents in GaAs

Peroxidase-mimicking DNAzyme was applied as a catalyst of silver deposition on gold nanoparticles. This DNAzyme is formed when hemin binds to the G-quadruplex-forming DNA sequence. Such a system is able to catalyze a redox reaction with a one- or two-electron transfer. The process of silver deposition was monitored via a localized surface plasmon resonance technique (LSPR), which allows one to record scattering spectrum of a single nanoparticle. Our study showed that DNAzyme is able to catalyze silver deposition. The AFM experiments proved that DNAzyme induced the deposition of silver shells of approximately 20 nm thickness on Au nanoparticles (AuNPs). Such an effect is not observed when hemin is absent in the system. However, we noticed non-specific binding of hemin to the capture oligonucleotides on a gold NP probe that also induced some silver deposition, even though the capture probe was unable to form G-quadruplex. Analysis of SEM images indicated that the surface morphology of the silver layer deposited by DNAzyme is different from that obtained for hemin alone. The proposed strategy of silver layer synthesis on gold nanoparticles catalyzed by DNAzyme is an innovative approach and can be applied in bioanalysis (LSPR, electrochemistry) as well as in material sciences

Steganography: Forensic, Security, and Legal Issues

Steganography has long been regarded as a tool used for illicit and destructive purposes such as crime and warfare. Currently, digital tools are widely available to ordinary computer users also. Steganography software allows both illicit and legitimate users to hide messages so that they will not be detected in transit. This article provides a brief history of steganography, discusses the current status in the computer age, and relates this to forensic, security, and legal issues. The paper concludes with recommendations for digital forensics investigators, IT staff, individual users, and other stakeholders

Tablet PCs for Teaching Information Systems Courses

The authors describe integration of and multiple uses for the tablet PC (TPC) in MIS classes. These uses are geared toward enhancing student learning through the TPC rather than learning how to use a specific tool. These technologies are used in a database course and an information security course to enhance student learning by having students participate in drawing entity relationship diagrams (ERD) and network configurations. Digital documents, annotated with digital ink are exchanged between faculty and students. A survey is used to capture perceptions of MIS majors regarding the value of the TPC in these two courses. These results are then compared and contrasted with results that have been previously published for TPCs in a database course. Results indicate that a major issue facing educators is the lack of critical mass in the adoption of TPCs by students

A First Approach in the Assessment of the Complexity of Disaster Recovery Models for SMEs

In an organization, a well devised disaster recovery plan is not only crucial in the information recovery process, but also vital in the quest to sustain daily operations. While prior research has discussed many recovery sites options, assessment of recovery site communication paths and their associated complexity is still limited in regard to the evaluation of disaster recovery (DR) models. Using the scale-free degree distribution formula, the authors present a methodical discussion concerning the network characteristics of various disaster recovery options. This study marks a pioneering effort in the DR field by applying the scale-free degree distribution formula to assess the network complexity index and overall model failure points. In addition, a modified hot model employing host virtualization designed especially for small and medium size businesses is presented. This method is particularly advantageous to small and medium size businesses as it leverages inexpensive commercial PC hardware