A 100-MHz macropipelined VAX microprocessor

A macropipelined CISC microprocessor was implemented in a 0.75-μm CMOS 3.3-V technology. The 1.3-million-transistor custom chip measures 1.62×1.46 cm² and dissipates 16.3 W. The 100-MHz parts were benchmarked at 50 SPEC marks. The on-chip clocking system and several high-performance logic and circuit techniques are described. Macroinstruction handling, micropipeline management, and control store structures highlight the design architecture. The hierarchical array organization and fast tag comparison technique of the primary cache are discussed. Power estimation procedures are outlined, and the results are compared to measurements. Physical design and verification methods, and CAD tools are also described. After extensive functional verification efforts are described, chip and system test results are presented     

Measurement of wood grain angle, moisture content and density using microwaves

In many wood products manufacturing processes, it is important to ensure that the physical properties of the raw material lie within acceptable ranges and are measured reliably. It is also important for practical use that the measurement process is robust, low-maintenance, fast and preferably non-contacting. This paper describes the development and demonstration of a microwave system for simultaneously identifying wood grain angle, moisture and density. The method involves propagating a microwave beam through the wood and measuring the resulting depolarization, attenuation and phase shift. The wood physical properties can then be identified from these measurements. In a series of measurements, the prototype microwave system successfully identified wood grain angles for hemlock and Douglas fir respectively with standard errors of 0.9° and 2.5° (measured range = -90° to +90°), moisture content 1.2% and 1.9% (measured range = 7–28%), moisture density 3.7 kg/m³ and 7.9 kg/m³ (measured range = 40–150 kg/m³, and dry density 16 kg/m³ and 30 kg/m³ (measured range = 325–625 kg/m³).     

Caractérisation minéralogique et géotechnique des argiles marneuses gonflantes de la région de Médéa,Algérie

This paper presents the approach followed for the geological, mineralogical, and geotechnical characterization of swelling marly clays in the Médéa region. This investigation is conducted in order to estimate the swelling potential of this marly clay layer. The studied sites, located at about 80 km south of Algiers, Algeria, cover an area of approximatively 400 hectares. Five sites are considered. In the first step, the geological, tectonic, climatic, and hydrological contexts of the region are described. According to the geological map of Médéa, most of the formations encountered in the area are composed of Miocene layers represented by marly clays (Fig. 2). This region is characterized by its high and low temperature in summer and winter, respectively, and variable humidity (Fig. 3). In a second step, the results of geotechnical studies, X-ray diffraction tests, chemical analyses, and scanning electron microscope (SEM) observations are presented (Figs. 3, 4, 5, 6, 7, 8, 9). The soils contain quartz (20–26 %), calcium carbonates (11–55 %), kaolinite (8–13 %), illite (6–14 %) and Montmorillonite (18–26 %). The study of their microstructure by means of SEM indicates that these soils are formed by a compact marly clay matrix that is relatively homogeneous and oriented in the dip direction of bedding. A grain size analysis shows that the clay content varies between 17 and 70 %. The water content of all samples varies between 8 and 30 %. The values of the liquidity limit (LL) and plasticity index (PI) vary between 28–76 % and 16–36 % respectively, indicating a highly plastic soil; this is also confirmed by a specific surface varying between 99 and 179 m²/g. The dry density γ _d varies between 15 and 19 kN/m³. The swelling potential of the marly clay samples is evaluated firstly using various indirect methods. In literature, a number of empirical classifications are proposed by different authors (BRE 1980; Chen 1988; Komornik and David 1969; Seed et al. 1962; Snethen 1984; Vijayvergiya et Ghazzaly 1973 et Williams and Donaldson 1980). The swelling potential is related to certain physical properties of soils, such as consistency limits, clay content, methylene blue value, etc. In general, these methods indicate that all the tested soils have a high swelling potential, which confirms the results of mineralogical analysis. Secondly, direct measurements of swelling parameters are performed. Swelling tests are carried out using a standard slaved one-dimensional odometer using two methods: free swell and constant volume, according to standard ASTM D 4546-90 and AFNOR (1995). The swell pressure, the swell percentage and the swell index are given in Fig. 16. It is noted that the soils develop very significant swell pressures which vary between 25 and 900 kPa. This is in agreement with the results obtained by empirical methods. This investigation clearly shows that the marly clays of the Médéa region have a high swelling potential. Therefore, taking into account the phenomenon of soil swelling in structure design is essential.     

A novel silk fibroin‐supported iron catalyst for hydroxylation of phenol

The aim of this study was to explore the potential use of silk fibroin (SF) as a catalyst support material for phenol hydroxylation reactions. Iron‐substituted silk fibroin fibers were prepared using formic acid at room temperature and characterized using inductively coupled plasma atomic‐emission spectrometry, scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR) and optical microscopy. Measurement of an FTIR spectrum showed that the secondary structure was β‐structure before and after iron substitution. To evaluate the catalytic properties of prepared catalyst, phenol hydroxylation reaction was carried out using aqueous hydrogen peroxide as an oxidant. An excellent transformation of phenol into dihydroxybenzenes (catechol and hydroquinone) was achieved. Phenol conversions of 3.3%, 61.2%, and 80.3% were obtained at room temperature, 40 °C and 60 °C respectively. It was found that no further phenol conversion proceeded because catalysts became separated from the reaction system during the reaction. No significant leaching of the iron was detected. Catalyst could be reused several times without a significant change in activity. Parent silk fibroin fibers without iron were inactive. Copyright © 2006 Society of Chemical Industry     

A model for the catabolism of rhizopine in Rhizobium leguminosarum involves a ferredoxin oxygenase complex and the inositol degradative pathway

Rhizopines are nodule-specific compounds that confer an intraspecies competitive nodulation advantage to strains that can catabolize them. The rhizopine (3-O-methyl-scyllo-inosamine, 3-O-MSI) catabolic moc gene cluster mocCABRDE(F) in Rhizobium leguminosarum bv. viciae strain 1a is located on the Sym plasmid. MocCABR are homologous to the mocCABR gene products from Sinorhizobium meliloti. MocD and MocE contain motifs corresponding to a TOL-like oxygenase and a [2Fe-2S] Rieske-like ferredoxin, respectively. The mocF gene encodes a ferredoxin reductase that would complete the oxygenase system, but is not essential for rhizopine catabolism. We propose a rhizopine catabolic model whereby MocB transports rhizopine into the cell and MocDE and MocF (or a similar protein elsewhere in the genome), under the regulation of MocR, act in concert to form a ferredoxin oxygenase system that demethylates 3-O-MSI to form scyllo-inosamine (SI). MocA, an NAD(H)-dependent dehydrogenase, and MocC continue the catabolic process. Compounds formed then enter the inositol catabolic pathway.     

Full-wave solutions for the depolarization of the scattered radiation fields by rough surfaces of arbitrary slope

Employing a variable coordinate system associated with the local features of two-dimensionally rough surfaces with arbitrary slope, full-wave solutions are derived for the depolarization of the scattered radiation fields. An outline of the analytical procedures used in the derivations of the solutions are presented. Furthermore, the engineer who is not familiar with them can also use the final result which is expressed as a definite integral whose integrand is given explicitly and in closed form. These full-wave solutions are compared with the quasi-optics solution and the iterative or perturbational solutions for slightly rough surfaces, and they are shown to bridge the wide gap that exists between them. The full-wave solutions are consistent with energy conservation, duality, and reciprocity relationships in electromagnetic theory. These solutions account for upward and downward scattering of the incident waves with respect to the horizontal reference plane, thus shadowing and multiple scattering are considered. Applications to two-dimensionally periodic structures and random rough surfaces are also presented. The fullwave solutions are examined for Brewster, grazing, and specular angles and backscatter. Special consideration is also given to good conducting boundaries.     

Rough surface scattering using specular point theory

The expression for the average scattering cross section for a random surface is derived using the stationary phase approximation for the scattered field due to specular points on a finitely conducting rough surface. A previous error in the literature is corrected by showing that the proper result is proportional to the average value of the product of the number of specular points per unit area and the principal radii of curvature at the specular point, rather than the product of the average value of the number of specular points and the average value of the radii of curvature. When the correct expression for the average value of the product is inserted in the expression for the scattering cross section, the result is in total agreement with the answers obtained when the averaging and stationary phase processes are interchanged. This analysis explicitly accounts for shadowing.     

Heteroepitaxial Growth Kinetics in a CVD Process Using Nickel Oxide on MgO as a Model System

Three-dimensional crysallites of NiO were grown on MgO substrates using a CVD process by reacting NiBr₂ with oxygen in the presence of water vapor at 600°C. The vapor pressures of oxygen and water vapor were kept at 0.88 and 2.61 kPa, respectively. The growth rate of periodically spaced NiO nuclei was measured. The results, which show a peak in the average deposition rate when plotted against the nuclei spacing, are modeled in terms of an effective diffusion distance for the NiO molecules on the MgO surface, and assuming a negligibly small reaction rate of the precursors on the surface of NiO crystallites. The latter assumption results from the observation that the average growth rate on cleaved MgO surface dropped to a very low value once a continuous film of NiO was formed. An effective diffusion distance was manifested by the observation of characteristic denuded zones surrounding the NiO crystallites when the nucleation rate was increased by increasing the water vapor supersaturation on the surface. The comparison with model is used to estimate the effective diffusion distance.     

Collective deformations in proteins determined by a mode analysis of molecular dynamics trajectories

A systematic method of representing and analyzing the intramolecular strains in proteins is proposed. For illustrative purposes, the method is applied to the N-terminal fragment of the human T-cell glycoprotein CD4. The method is based on the singular value decomposition (SVD) of molecular dynamics (MD) trajectories. The slowest three modes of motion that carry information along the protein molecule over large length scales are analyzed, so as to characterize the collective motions and the resulting strains along the three principal axes of the protein. Strong cooperative motions of different types, mainly wave-like, wagging, wiggling, breathing, bending and shearing motions, and rigid body rotations are distinguished. The mean-square fluctuations of C^α-atoms induced by the three dominant modes are found to exhibit a closer correlation with the experimental temperature factors in the presence of solvent.     

Polymorphisms in the bovine lactoferrin promoter are associated with reproductive performance and somatic cell count

Lactoferrin plays an important role in the innate immune system, with well-characterized antibacterial, antiviral, and immune modulatory properties. The objective of this study was to determine the allele and haplotype frequency of polymorphisms at positions −586, −190, and −28 of the bovine lactoferrin promoter in Holstein-Friesians and to quantify their association with performance using phenotypic data on progeny from 848 sires. Associations between genotypes and performance were quantified using weighted mixed models with genotyped individuals included as a random effect, and average expected relationships among individuals accounted for through a numerator relationship matrix. The dependent variables were daughter yield deviation for production traits and deregressed predicted transmitting ability for calving interval and functional survival. The C to T polymorphism at −586, which distorts a putative activating protein 2 (AP-2) binding site, was associated with a shorter calving interval and higher somatic cell score. The G to A polymorphism at −190, located in a putative selective promoter factor 1 (SP-1) binding site, was associated with a longer calving interval and decreased functional survival. A third polymorphism (A to C) at position −28, found within the noncanonical TATA box, had a tendency to associate with functional survival. On the basis of the data we proposed a haplotype combination that was associated with improved reproductive performance in the Holstein-Friesian breed. We hypothesized that the observable phenotypic associations with lactoferrin promoter polymorphisms can potentially be explained by allele-specific differences in constitutive or inducible levels of gene expression. The lack of a pleiotropic effect of the single nucleotide polymorphisms studied on both fertility and milk production traits strengthens the importance of these polymorphisms, or at least the lactoferrin promoter, in selection for improved fertility.