Phylogenetic scanning: a computer-assisted algorithm for mapping gene conversions and other recombinational events

An algorithm, 'phylogenetic scanning', is described for mapping gene conversion events where comparative DNA sequence data are available from different species. In this algorithm, sets of hypothetical phylogenetic trees are constructed that describe possible sequence relationships due to gene conversions in different species lineages; these trees are then evaluated by the principle of parsimony at intervals in the sequence alignment. When used to map gene conversion events that occurred between the pair of gamma-globin genes of higher primates, the algorithm gives results nearly identical to those obtained using a tedious manual approach. Suggestions are also provided for adaptation of this procedure to the analysis of other recombination events.     

Agent-based substation automation

Agent technology is one of the most interesting developments in the field of distributed artificial intelligence. It has a wide range of applications, with information management, intelligent user interfaces, personal assistants, and Internet commerce among the most popular. This article defines a generic architecture that applies the multiagent systems methodology to the field of substation automation, describes the design of a system to be implemented based on this architecture, and proposes several possible applications. Compared with SCADA or client-server substation automation solutions, an agent-based system offers a number of advantages. Each function or task of the system, such as the management of a single IED, can be encapsulated within a separate agent, making the system highly modular. Agents are loosely coupled, typically communicating via messaging rather than by procedure calls (remote or local), and, using directory services, new functions can easily be added to an agent-based system by creating a new agent, which will then make its capabilities available to others. The inherently distributed power system architecture is suited ideally to a multiagent system, which provides greater autonomy to each of the constituent parts than a traditional system.     

Effects of sex and MK-801 on auditory-processing deficits associated with developmental microgyric lesions in rats

Neonatally induced microgyric lesions produce defects in rapid auditory processing in adult male rats. Given that females across species are less susceptible to the deleterious effects of neural injury and that treatment with neuroprotective agents at the time of injury can reduce neural damage, the authors tested the effects of sex and neuroprotectant exposure on the behavioral consequences of microgyric lesions in rats. Results showed that sham but not microgyric males were able to perform the task at the fastest rate of stimulus presentation. Microgyric females, in contrast, discriminated at all stimulus conditions and did not differ from female shams. Microgyric males treated with MK-801 had reduced cortical damage and performed the discrimination at the fastest condition. Results suggest that females are less susceptible to the behavioral effects of neocortical microgyria and that MK-801 may ameliorate the behavioral consequences of these lesions in male rats.     

Design and Characterization of the CLIMPAQ,Chamber for Laboratory Investigations of Materials,Pollution and Air Quality*

A test chamber has been developed in order to provide a small and simple emission testing facility capable of testing construction products in a climate where the important climatic parameters such as temperature, ventilation rate and air velocity can be varied independently around typical indoor values. The test chamber CLIMPAQ is made of panes of window glass. Other main surface materials are stainless steel and eloxated aluminium. The chamber has a volume of 50.9 litres and is designed to meet the requirements for quantifying air pollution. In this investigation human subjects acted as air pollution judges, and chemical characterization of the air pollution was carried out. Carpet, linoleum, wall paint and seal- ant were tested simultaneously in the CLIMPAQ and in four other chambers ranging from a full-scale chamber of 28 m³ to a field and laboratory emission cell of 3.5· 10^?5m³. Product ranking is the same in all chambers for the sensory measurements. Emission rates based on sensory measurements differ for all products less than 100 % except for tests in a 3-litre chamber where emission rates were higher. Chemical measurements differ up to approximately 10 times for the same product in different chambers. Deviations appear to be the result of different environmental parameters in the various chambers. Low air concentrations or high specific ventilation rates seem to increase emissions, while differences in air velocities and sink properties may also be the cause of differences in emission rates.     

Effects of Sc2O3 and MgO passivation layerson the output power of AlGaN/GaN HEMTs

The low temperature (100°C) deposition of Sc₂O₃ or MgO layers is found to significantly increase the output power of AlGaN/GaN HEMTs. At 4 GHz, there was a better than 3 dB increase in output power of 0.5×100 μm² HEMTs for both types of oxide passivation layers. Both Sc₂ O₃ and MgO produced larger output power increases at 4 GHz than conventional plasma-enhanced chemical vapor deposited (PECVD) SiN_x passivation which typically showed ⩽2 dB increase on the same types of devices. The HEMT gain also in general remained linear over a wider input power range with the Sc₂O₃ or MgO passivation. These films appear promising for reducing the effects of surface states on the DC and RF performance of AlGaN/GaN HEMTs     

Classification of slice-based VBR video traffic and estimation of link loss by exceedance

Classification of a video stream is an essential preliminary step to estimate the bit loss when the video stream is transmitted over a communication network. In this paper, we classify the video frames by the average frame size and estimate the bit loss for each class when the bitrate exceeds the capacity of the bottleneck link. The video stream under study is encoded using the explicit slice-based H.264/AVC encoding scheme. This scheme reduces the burstiness of regular H.264/AVC encoded video by removing the traditional GOP structure. Instead, a repetitive combination of intracoded and predicted slices is employed, thereby introducing a specific dependence structure in the video data. We consider a bufferless model of the communication system and evaluate the channel capacity required to give a maximum allowed loss rate for each class.Due to the high variability, non-stationarity and non-homogeneity of the underlying video data, the obtained classes are checked regarding the dependence and distribution structure of the data. The high quantiles of the losses are estimated for each class.     

Anomalous Thermal Expansion in Superconducting Mg1− x Al x B2 System

The thermal lattice expansion in the superconducting Mg_{1? x} Al _x B₂ system (x = 0, 0.13, and 0.59) has been measured using high-resolution X-ray powder diffraction. An unusual large negative thermal expansion (NTE) appears for temperatures below T ^* = 60 K in the MgB₂. The NTE effect increases in Mg_0.87Al_0.13B₂ and disappears at high Al content in the Mg_0.59Al_0.41B₂ where the temperature dependence of volume follows a standard Einstein model in the whole temperature range. The anomalous behavior of the thermal expansion provides a direct evidence in the physics of diborides for the relevance of the proximity to the 2.5 Lifshitz electronic topological transition where the Fermi surface of the σband changes from a two-dimensional (2D) to a three-dimensional (3D) topology.     

Life-cycle modeling for adaptive and variant design. Part 1: Methodology

Life-cycle modeling for design (LCMD) is a methodology for assessing the life-cycle impacts for a complex product with many individual components starting from initial design phases when few design specifications have been made. The methodology combines life-cycle assessment (LCA) with probabilistic design methods in a way that forecasts attributes of possible final designs yet reduces information needs. Specifically, LCMD is a methodology for generating arrays of design scenarios that communicate the range of designs being considered by a design team, and estimating missing data for those design scenarios. The main contribution to enhancing standard LCA is the incorporation of methods to estimate physical attributes of individual components for various design options and in four analyses for evaluating the arrays of design scenarios. An automotive case study presented in part 2 of this work demonstrates one application of LCMD.