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Viroids are small, proteinless single-stranded circular RNAs. In plants, they can be transmitted via infected pollen and seeds. The effectiveness of viroid transmission through pollen depends on both the viroid and host species. It is, however, unclear whether viroid variant type or infection stage influences seed transmission through pollen. In the present study, we collected pollen from petunia infected with nine different variants of the potato spindle tuber viroid (PSTVd) at various stages after inoculation and used the material to pollinate healthy plants. Five and eight PSTVd variants were transmitted by pollen at 3 and 6 mpi respectively. All variants were pollen-transmissible at 9 mpi. The foregoing results indicated that seed transmission of PSTVd through pollen collected from infected donor plants may depend on the time elapsed since inoculation. For variant no. EU862231, however, the rate of seed transmission via pollen may depend on the pollen viroid titre. Nevertheless, there was no apparent correlation between the transmission rate and the pollen viroid titre in the U23058 or V01465 variant. Hence, the relationship between the viroid transmission rate and the pollen viroid titre may depend on the viroid variant type.

Supplemental material, DS_10.1177_0022034520925080 for TBX1 Regulates Chondrocyte Maturation in the Spheno-occipital Synchondrosis by N. Funato, D. Srivastava, S. Shibata and H. Yanagisawa in Journal of Dental Research

Maintenance of cell volume against osmotic change is crucial for proper cell functions, such as cell proliferation and migration. The leucine-rich repeat-containing 8 (LRRC8) proteins are anion selective channels, and were recently identified as pore components of the volume-regulated anion channels (VRACs), which extrude anions to decrease the cell volume upon cell-swelling. Here, we present the human LRRC8A structure, determined by a single-particle cryo-electron microscopy analysis. The sea anemone-like structure represents a trimer of dimers assembly, rather than a symmetrical hexameric assembly. The four-spanning transmembrane region has a gap junction channel-like membrane topology, while the LRR region containing 15 leucine-rich repeats forms a long twisted arc. The channel pore is along the central axis and constricted on the extracellular side, where the highly conserved polar and charged residues at the tip of the extracellular helix contribute to the anion and other osmolyte permeability. Comparing the two structural populations facilitated the identification of both compact and relaxed conformations, suggesting that the LRR region is flexible and mobile with rigid-body motions, which might be implicated in structural transitions upon pore opening. Overall, our structure provides a framework for understanding the molecular mechanisms of this unique class of ion channels.

Supplemental Material

A major challenge in the initial stage of production planning for the steel industry is the material allocation problem (MAP): finding the best match of orders and materials (steel slabs and coils) with respect to an objective function that takes into account order due dates, preferences for matches, allocated weights, surplus weights of materials, and other factors. The MAP is NP-hard and is difficult to solve optimally. We apply a local search algorithm for the MAP that includes rich moves, such as ejection chain methods. Our algorithm is yielding considerable cost reduction in a real steelworks. In particular, a two-variable integer programming (TVIP) neighborhood search technique contributed to the cost reductions. TVIP defines a neighborhood space for the local search as a two-variable integer programming problem and efficiently finds a solution in the neighborhood. By using TVIP, the number of small batches of surplus material can be successfully reduced.

Reference LPS-ARTICLE-2006-004doi:10.1016/j.susc.2006.07.007View record in Web of Science Record created on 2007-06-20, modified on 2016-08-08

During the growth of stable BC3 (s-BC 3 ) sheets on NbB 2 (0001), metastable BC 3 (m-BC 3 ) honeycomb epitaxial sheets appeared first. The properties of the m-BC 3 sheets were investigated by using LEED, AES, HREELS, and ab initio calculations. The observed lattice constant was longer by 5% than that of the s-BC 3 sheets, while the stoichiometric ratio of boron to carbon of the m-BC 3 was almost the same as that of the s-BC 3 . The observed energies of the longitudinal optical and longitudinal acoustic phonons with in-plane polarization were lower than those of the s-BC 3 sheets, which indicated a reduction of the force constants due to the lattice expansion. The experimental phonon energies of the m-BC 3 sheets were in good agreement with those generated by ab initio calculations of the lattice dynamics for an optimized monolayer-model structure. This structure was determined by optimizing the atomic positions in a unit cell with the observed lattice constant; the optimized values of the C-C and B-C bond lengths were l C-C = 0.146 nm and l B-C = 0.164 nm.

This paper proposes a new robust tracking servo system for the optical disk recording system with feedforward controller based on the prediction of the tracking error. In optical recording systems, the feedback servo system must suppress the influence of force disturbance and parameter variation. To overcome this problem, this paper designs the robust feedback control system by using coprime factorization and disturbance observer. The detecting signal of the optical disk recording system is only a tracking error. Hence, the feedforward controller of the proposed tracking control system is constructed based on both the "zero-phase-error tracking" control theory and the prediction of the tracking error. The experimental results point out that the proposed tracking servo system has a quick and precise tracking response and keeps the residual tracking error below its tolerance.

We have investigated the surface electronic structures of transition-metal diboride (0001) surfaces by angle-resolved ultraviolet photoelectron spectroscopy (ARUPS) and ab-initio calculations based on the slab model with 13 layers. In the spectra of NbB2 and TaB2, the peaks near -1 eV blow EF are derived from the π band of their surface graphitic boron layer. As compared with graphene, the dispersion curves of the π bonds are greatly modulated by the hybridization of B-π orbits with the metal d orbits. On the other hand, the similar peaks were not observed in spectra of ZrB2, of which the surface is terminated with Zr atoms. [DOI: 10.1380/ejssnt.2006.100]

We have successfully grown a uniform BC3 honeycomb sheet with high crystalline quality over the entire macroscopic area of the NbB2 (0001) surface by carbon-substituted technique in a boron honeycomb. This is the first macroscopic uniform sheet of single-crystal BC3 with a monolayer thickness. So far, only BC3 micro-crystals with radii of a few nanometres were produced. The properties of the sheet have been investigated by using XPS, AES, LEED, STM, ARUPS and HREELS. All the experimental data and the theoretical calculations, which are concerning with atomic structure, chemical concentration, and phonon structure, indicated that the uniform BC3 honeycomb sheet was grown in an epitaxial manner to the substrate lattice.

We have grown epitaxial thin sheets of graphene on BC 3 /NbB 2 (0001) and measured phonon dispersion curves of the graphene sheets by means of high-resolution electron energy-loss spectroscopy (HREELS). The phonon dispersion curves have been calculated on the basis of ab initio calculations. The observed curves were in good agreement with theoretical curves. The quality of crystallinity of the graphene layers was high compared with the bulk graphite crystals. In this paper, we demonstrate that the combination of HREELS measurement and ab initio calculations is extremely effective for investigation of honeycomb-structured materials.

Using a diffraction approach the convolution-type integral equation for the laser schlieren signal created by an arbitrary disturbance at low pressure, where refractive index of disturbance is close to unity, in a shock tube (thin optical layer) has been deduced. In the equation electric circuit relaxation processes were taken into account by a response function. The equation was solved with the aid of the regularization method worked out for ill-posed problems. The density structures of the strong shock waves in air have numerically been reconstructed from experimental data ranging shock wave Mach number of $M_s=20$ –30, and $P_0=10$ –30 Pa.

Cloud computing has become very popular in recent years. Various PaaS (Platform as a Service) systems for collaborative software development as well as DaaS (Desktop as a Service) systems for developing software have been proposed. Software development environments are categorized as one of four types: Client-side Development and Client-side Execution, Client-side Development and Server-side Execution, Server-side Development and Server-side Execution (SDSE), and Server-side Development Client-side Execution (SDCE). Most PaaS and DaaS systems assume that applications are developed on a server and executed on the same server. As such, portability of these applications is not considered. In order to improve the portability of the developed software and establish efficiency in the development environment, we propose SDCE and SDSE environments. The SDCE environment provides a Web-based software development environment for graphical user interface applications that can be executed on a local machine, while the SDSE environment provides a Web-based interactive application execution environment for console user interface applications that can be executed on the server.

TiN films were prepared by reactive sputtering using a radio-frequency magnetron sputtering system. Ti films containing nitrogen were also formed, depending on nitrogen flow. For all films the crystal structure, chemical binding state and composition were investigated. An abrupt transition occurred in the narrow region between 7% and 8% nitrogen flow. Other phases like Ti2N or amorphous state were not observed in the transition process. The electrical resistivity of TiN prepared at 400°C with 8% of nitrogen flow was 24 μΩ cm, equivalent to that of bulk TiN. Films showed low resistivity at higher nitrogen flow (10% and 12%). Films kept low resistivity (30 μΩ cm) at 50 nm thickness, and the continuity of the film was confirmed even at 5 nm thickness.

Low-threshold operation of 630-nm AlGaInP LD's is examined by introducing compressive and tensile strains into quantum wells (QW's), and the dependence of threshold currents on the effects of strain is investigated. We also try to determine the correlation between the strain-induced polarization mode and threshold currents so as to optimize the strained QW structure for low threshold operation. Experimental results reveal a good correlation when the same device parameters are used. Based on that correlation, applying the larger strain and the QW-structure design that enhances the main polarization mode is effective in obtaining a low threshold. Opposite dependences of the relative intensity of the polarization mode on such device parameters as cavity length and facet reflectivity are observed under the two types of strain. Under tensile strain, the polarization-mode intensity increases as the mirror loss increases and the device temperature rises. >

In situ monitoring by surface photo-absorption (SPA) was used in metalorganic vapor phase epitaxy (MOVPE) growth of Ga 0.5 In 0.5 P ternary alloy semiconductor for the first time. Two modes were employed to supply the group III precursors: the alternate supply and the simultaneous supply. Monolayer-wise growths per supply cycle are possible for both growth modes. X-ray diffraction measurement and transmission electron microscopy (TEM) observation show that lattice mismatch of GaInP epitaxial layers can be controlled when a simultaneous supply is employed. Photoluminescene (PL) was measured for single GaInP layers and GaInP/AlGaInP double hetero (DH) structures grown at various temperatures. The results show that the PL intensity greatly depends on the growth temperature

Hole concentration of p(Zn)-(Al 0.7 Ga 0.3 ) 0.5 In 0.5 P grown by organometallic vapor phase epitaxy is influenced by cooling atmospheres and capping layers. A high hole concentration is obtained when an epitaxial layer is cooled in a hydrogen stream, while cooling in a phosphine- or arsine-containing hydrogen atmosphere reduces hole concentration in this order. A cap layer, n- or p-GaAs is useful in maintaining a high hole concentration. The zinc acceptors in a layer with a low hole concentration can quickly be reactivated by annealing in hydrogen.

When commutator profile distortion in DC motors or collector ring profile distortion in AC generators or motors are caused, stabilities and reliabilities of sliding contact phenomena will be lost, causing mechanical contact instabilities and contact voltage instabilities. In this paper, how to estimate the mechanical vibration out of the ring profile distortion and how to estimate contact voltage deviation out of the mechanical vibration, are introduced.

SSC-DASH (Server Side C-like Design Automation Shell) has been developed as a Web-based HW/SW codesign tool for designing processors. SSC-DASH obtains a processor definition file via Web browser and generates a HW (synthesizable Verilog-HDL description) and SWDE (Software Development Environment) for the generated processor. The SWDE includes ISS (Instruction Set Simulator), assembler, disassembler and compiler. For the verification of the defined processor, processor developers have to download the generated SWDE, every time, even where changes are small. To improve the usability of this system a Web-based interface for the generated SWDE is implemented using Ajax. Using Ajax, download of the SWDE becomes unnecessary and makes it possible to verify the processor on the server quickly and easily. This greatly improves the usability of the SWDE. In this paper, we describe implementation of Web-based ISS using Ajax.

To develop an embedded system, in which processors are used, a skilled assembler is necessary. An ISA (instruction set architecture) simulator is essential for training assembly programming, and the preparation of a SWDE (software development environment) such as simulator, assembler, disassembler, and compiler for a new processor can put a great strain on processor developers. We have been developing C-DASH (C-like design automation shell), a hardware/software codesign tool for processors that can generate an instruction set level simulator based on a character user interface. In this paper, we construct a graphical user interface for a simulator and describe the utilization of the simulator for education

We have investigated experimentally and theoretically the phonon-dispersion curves along the $\overline{\ensuremath{\Gamma}}\text{\ensuremath{-}}\overline{M}$ axis in two-dimensional surface Brillouin zones of the stable and metastable $\mathrm{B}{\mathrm{C}}_{3}$ honeycomb sheets with different lattice constants. Most of the observed curves agreed with the theoretical ones calculated on the basis of the ab initio theory. There exists a common relationship between the nearest-neighbor stretching force constants and bond lengths of two-dimensional honeycomb structures in various compounds of boron, carbon, and nitrogen; the two-dimensional bonds are discriminated clearly from the one- and three-dimensional bonds. We detected a librational mode of carbon hexagons in $\mathrm{B}{\mathrm{C}}_{3}$; a peculiar mode for a large unit cell of honeycomb sheets such as the $2\ifmmode\times\else\texttimes\fi{}2$ structure of monolayer graphite and $\mathrm{B}{\mathrm{C}}_{3}$. The restoring force related with the bond bending is insensitive to the change in the B-C bond length.

We have developed a processor development environment C-DASH (C-like Design Automation Shell). C-DASH generates HW (Hardware) and SWDE (Software Development Environment) from a processor definition file. To use C-DASH, each user must install C-DASH into local PC. When developing a processor as a team there is often a problem of file consistency, such as when another developer changes the same files you have. To solve this problem a collaborative development environment is required. This paper describes the implementation of a server side ubiquitous codesign environment for an ISA simulator. A server side codesign environment makes it unnecessary to install C-DASH onto local hosts, and makes codesign environment into device independent, and collaborative development becomes easier. A developer can upload a processor definition file via a web browser and develop an ISA (Instruction Set Architecture) simulator.

To develop an embedded system, in which processors are used, a skilled assembler is necessary. An instruction set simulator is essential for training assembly programming, and the preparation of a software development environment (such as simulator, assembler, disassembler, and compiler) for a new processor can put a great strain on processor developers. We have been developing C-DASH (C-like Design Automation Shell), a Hardware/Software codesign tool for processors that can generate an instruction set level simulator based on a CUI (Character User Interface). In this paper, we construct a GUI (Graphical User Interface) for a simulator and describe the utilization of the simulator for education. We used the simulator in classroom and evaluate the simulator.

In recent years there has been intensive study on shortening the lasing wavelength of AlGaInP laser diodes by introducing a quaternary active layerl or a ternary quantum well (QW) structure. CW operation at the lasing wavelength of 633 nm, which corresponds to that of a He-Ne gas laser, has been attained by adopting a multiquantum well (MQW) structure with very thin QWs. However, the performance at high temperatures was not good enough to allow an operating temperature higher than 50/spl deg/C. This is thought to be caused by significant carrier overflow from the active layer, which tends to increase with shorter lasing wavelength as the bandgap difference between the active layer and the cladding layers becomes smaller. We first evaluate the effect of the number of QWs on the carrier confinement and the high-temperature characteristics, and then use the results to optimize the structure of an MQW made on misoriented substrates.

The entire phonon-dispersion curves along the Gamma-M direction of a BC3 honeycomb sheet have been determined both experimentally and theoretically for the first time. Most of the observed curves agreed with the theoretical ones calculated on the basis of ab initio theory. From the stretching force constants of the nearest-neighbor C-C and B-C bonds, together with that of the B-B bond, we clarified the characteristic feature of the C-C and B-C bonds. From the experimental and theoretical results, we discussed the possibility of high T(c).

This paper proposes a new robust tracking servo system for optical disk recording system with feedforward controller based on prediction of tracking error. In optical recording systems, the feedback servo system must suppress the influence of the force disturbance and parameter variation. For this purpose, this paper designs the robust feedback control system by using the coprime factorization and disturbance observer. The detecting signal of optical disk recording system is only a tracking error. Hence, the feedforward controller of the proposed tracking control system is constructed based on both "zero phase error tracking" (ZPET) control theory and prediction of tracking error. The experimental results point out that the proposed system has a quick and precise tracking response and keeps the residual tracking error below tolerance.

This paper proposes a new feedforward tracking servo system for optimal disk recording system based on prediction of tracking error. In the optical disk recording systems, its detecting signal is only a tracking error. The tracking servo system, such as CD-R, must have the complete tracking response whose error is less than 0.1[/spl mu/m] of position reference. For this purpose, this paper proposes a new tracking servo system based on prediction of tracking error. The proposed robust feedforward tracking control system is constructed both "zero phase error tracking" (ZPET) control system and robust feedback control system. Moreover, this paper considers the saturation of controller input. The experimental results point out that the proposed system has a quick and precise tracking response and keeps the residual tracking error below this tolerance smoothly and stably.

To develop an ASIP (application specific instruction set processor), development of HW (hardware) and development of SWDE (software development environments) are required. Separate develops of HW and SWDE in a short time are difficult. So HW/SW codesign system is necessary rapid develop of ASIPs. We have developed C-DASH(c-like design automation shell), which is a HW/SW codesign system for designing processors based on ISA (instruction set architecture). We describe the HW/SW codesign system C-DASH, along with a description of a Java processor that directly executes Java byte code is given as an example.

The entire phonon-dispersion curves along the Gamma-M direction of a BC3 honeycomb sheet have been determined both experimentally and theoretically for the first time. Most of the observed curves agreed with the theoretical ones calculated on the basis of ab initio theory. From the stretching force constants of the nearest-neighbor C-C and B-C bonds, together with that of the B-B bond, we clarified the characteristic feature of the C-C and B-C bonds. From the experimental and theoretical results, we discussed the possibility of high T(c).

To develop newly designed processors, it is usually important to develop a software development environment such as assemblers, dis-assemblers, compilers and simulators, as well as designing of target hardware. This is a serious problem for new processor developments, especially for embedded systems. In order to solve this problem, we are developing an ISA based system design language C' (C-like Design Automation Shell) which develops both the processor's hardware core and related software tools, at once. We present the overview of ISA based system design language C'.

This paper proposes a new robust feedforward tracking servo system for optical disk recording system based on prediction of tracking error. In optical disk recording systems, its detecting signal is only a tracking error. The tracking servo system, such as CD-R, must have a complete tracking response whose error is less than 0.1 /spl mu/m for amplitude of 100 /spl mu/m of position reference. For this purpose, this paper proposes a new tracking servo system based on the prediction of the tracking error. The proposed robust feedforward tracking control system is constructed by both a "zero phase error tracking" (ZPET) control system and a robust feedback control system. Moreover, this paper considers the saturation of the controller output. The experimental and numerical simulation results point out that the proposed system has a quick and precise tracking response and keeps the residual tracking error below this tolerance smoothly and stably.

The paper describes the development of a new type of radar system called Chaotic Signal Radar (CSR), which utilises truly random signals for the modulation and a novel implicit sampling averaging algorithm in the receiver. The paper presents the results of simulation study in conjunction with the real measurements using a prototype CSR.

The Drosophila spinster (spin) gene product is required for programmed cell death in the nervous and reproductive systems. We have identified a human homologue of the Drosophila spin gene product (HSpin1). HSpin1 bound to Bcl-2 and apoptosis regulator Bcl-X (Bcl-xL), but not to proapoptotic members such as Bcl-2-associated X protein and Bcl-2 homologous antagonist killer, in cells treated with TNF-alpha. Exogenous expression of HSpin1 resulted in the cell death without inducing a release of cytochrome c from mitochondria. Overexpression of Bcl-xL inhibited the HSpin1-induced cell death. Interestingly, a necrosis inhibitor, pyrrolidine dithiocarbomate, but not the pancaspase inhibitors, carbobenzoxy-VAD-fluoromethyl ketone and p35, blocked the HSpin1-induced cell death. HSpin1-induced cell death increases autophagic vacuole and mature form of cathepsin D, suggesting a novel caspase-independent cell death, which is link to autophagy.

The optimum design for tensile-strained quantum-well structures, and the laser characteristics of AlGaInP LDs emitting at 615-635 nm are investigated. MQW structures are effective in reducing threshold currents at wavelengths shorter than 620 nm. The lowest threshold current of 95 mA at 20 degrees C is attained in a quaternary MQW LD emitting at 615 nm.

Optimized thin quantum-well (QW) structures under compressive strain are examined for high-power characteristics suitable for light sources of optical disk systems. As a result, compressively strained triple-quantum-well LDs can operate stably at 40 mW and a high temperature of 60/spl deg/C for over 1000 hours.

Summary form only given. Low-threshold CW operation of 630-nm AlGaInP LDs with compressive- or tensile-strained quantum-well structures is investigated. In addition, the correlation between the threshold current and polarization-mode intensity is discussed in terms of strain effects and injected carrier density.

This paper proposes a new robust feedforward tracking control system for optical disk recording system, which is based on both "zero phase error tracking" (ZPET) control and a robust feedback control using disturbance observer and coprime factorization. Optical disk recording systems must have a quick and precise tracking control whose error is less than 0.1 /spl mu/m for a position reference with amplitude of 100 /spl mu/m. For this purpose, optical disk recording systems should be regulated by feedforward control and robust control. However, the detection signal is only a tracking error and the position reference cannot be obtained. Therefore, this paper proposes a new estimation method of the position reference by using only tracking error, and realizes a quick and precise tracking control based on feedforward control and robust control.