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We present Light-Seq, an approach for multiplexed spatial indexing of intact biological samples using light-directed DNA barcoding in fixed cells and tissues followed by ex situ sequencing. Light-Seq combines spatially targeted, rapid photocrosslinking of DNA barcodes onto complementary DNAs in situ with a one-step DNA stitching reaction to create pooled, spatially indexed sequencing libraries. This light-directed barcoding enables in situ selection of multiple cell populations in intact fixed tissue samples for full-transcriptome sequencing based on location, morphology or protein stains, without cellular dissociation. Applying Light-Seq to mouse retinal sections, we recovered thousands of differentially enriched transcripts from three cellular layers and discovered biomarkers for a very rare neuronal subtype, dopaminergic amacrine cells, from only four to eight individual cells per section. Light-Seq provides an accessible workflow to combine in situ imaging and protein staining with next generation sequencing of the same cells, leaving the sample intact for further analysis post-sequencing.

Super-resolution chromatin imaging techniques are emerging as powerful tools for spatial genomics. However, it remains challenging to visualize the genome on the order of tens of nanometers, a scale that can reveal rich structural detail about the nuclear organization. Here we introduce Decode-PAINT, a multiplexed in situ method, which leverages rapid diffraction-limited pre-decoding and DNA-PAINT (DNA points accumulation for imaging nanoscale topography). Decode-PAINT visualizes multiple discrete genomic regions at a resolution close to the nucleosome scale with a simple and easy-to-implement optical setup, reduces total imaging time by omitting multiple rounds of single-molecule recording, and enables the interrogation of the ultrastructure of the targets with

The strength evaluation of structures that requires high reliability, such as power generation facilities, is extremely important. It is necessary to ensure safety under extremely low cycle fatigue caused by earthquakes. However, a highly reliable evaluation method has not yet been developed because of variable fracture toughness due to the constraint effect with large deformation. The crack propagation criterion proposed by the previous study has needed some modification for accurate prediction. In this study, we confirmed whether the crack propagation criterion proposed by previous study can reproduce the fracture behavior of the experiment. Among then, relationship between the number of cycle and crack length, hysteresis loop, reproduction of crack shape were evaluation items.

Transformative technologies are enabling the construction of three-dimensional maps of tissues with unprecedented spatial and molecular resolution. Over the next seven years, the NIH Common Fund Human Biomolecular Atlas Program (HuBMAP) intends to develop a widely accessible framework for comprehensively mapping the human body at single-cell resolution by supporting technology development, data acquisition, and detailed spatial mapping. HuBMAP will integrate its efforts with other funding agencies, programs, consortia, and the biomedical research community at large towards the shared vision of a comprehensive, accessible three-dimensional molecular and cellular atlas of the human body, in health and under various disease conditions., HuBMAP supports technology development, data acquisition, and spatial analyses to generate comprehensive molecular and cellular three-dimensional tissue maps.

© 2019, The Author(s), under exclusive licence to Springer Nature America, Inc. Spatial mapping of proteins in tissues is hindered by limitations in multiplexing, sensitivity and throughput. Here we report immunostaining with signal amplification by exchange reaction (Immuno-SABER), which achieves highly multiplexed signal amplification via DNA-barcoded antibodies and orthogonal DNA concatemers generated by primer exchange reaction (PER). SABER offers independently programmable signal amplification without in situ enzymatic reactions, and intrinsic scalability to rapidly amplify and visualize a large number of targets when combined with fast exchange cycles of fluorescent imager strands. We demonstrate 5- to 180-fold signal amplification in diverse samples (cultured cells, cryosections, formalin-fixed paraffin-embedded sections and whole-mount tissues), as well as simultaneous signal amplification for ten different proteins using standard equipment and workflows. We also combined SABER with expansion microscopy to enable rapid, multiplexed super-resolution tissue imaging. Immuno-SABER presents an effective and accessible platform for multiplexed and amplified imaging of proteins with high sensitivity and throughput.

Fluorescence in situ hybridization (FISH) reveals the abundance and positioning of nucleic acid sequences in fixed samples. Despite recent advances in multiplexed amplification of FISH signals, it remains challenging to achieve high levels of simultaneous amplification and sequential detection with high sampling efficiency and simple workflows. Here we introduce signal amplification by exchange reaction (SABER), which endows oligonucleotide-based FISH probes with long, single-stranded DNA concatemers that aggregate a multitude of short complementary fluorescent imager strands. We show that SABER amplified RNA and DNA FISH signals (5- to 450-fold) in fixed cells and tissues. We also applied 17 orthogonal amplifiers against chromosomal targets simultaneously and detected mRNAs with high efficiency. We then used 10-plex SABER-FISH to identify in vivo introduced enhancers with cell-type-specific activity in the mouse retina. SABER represents a simple and versatile molecular toolkit for rapid and cost-effective multiplexed imaging of nucleic acid targets.

We present Light-Seq, an approach for multiplexed spatial indexing of intact biological samples using light-directed DNA barcoding infixed cells and tissues followed by ex situ sequencing. Light-Seq combines spatially targeted, rapid photocrosslinking of DNA barcodes onto complementary DNAs in situ with a one-step DNA stitching reaction to create pooled, spatially indexed sequencing libraries. This light-directed barcoding enables in situ selection of multiple cell populations in intact fixed tissue samples for full-transcriptome sequencing based on location, morphology or protein stains, without cellular dissociation. Applying Light-Seq to mouse retinal sections, we recovered thousands of differentially enriched transcripts from three cellular layers and discovered biomarkers fora very rare neuronal subtype, dopaminergic amacrine cells, from only 4–8 individual cells per section. Light-Seq provides an accessible workflow to combine in situ imaging and protein staining with next generation sequencing of the same cells, leaving the sample intact for further analysis post-sequencing.

Fatigue cracks have recently been reported at out-of-plane gusset welded joints in main girders of old existing steel girder highway bridges on heavy traffic routes. These cracks are potentially dangerous and may cause the main girder to break. Therefore, strategic maintenance is of particular importance in addition to periodic inspection. In this paper, a simplified method for the estimation of live load stress for fatigue evaluation is discussed on the basis of load distribution factor (LDF). The relationship between structural parameters and fatigue live load stress is investigated. The proposed method is based on 22 data sets computed by grillage analysis of 14 girder bridges with various structural parameters. Regression analyses based on these data sets are conducted and practical equations are extracted to estimate the fatigue damage caused by live load stress. Simplified equations are proposed as a function basic bridge parameters, which provide good approximate estimates for the analysis values.

We report the single-strand Recombinase Polymerase Amplification (ssRPA) method, which merges the fast, isothermal amplification of RPA with subsequent rapid conversion of the double-strand DNA amplicon to single strands, and hence enables facile hybridization-based, high-specificity readout. We demonstrate the utility of ssRPA for sensitive and rapid (4 copies per 50 µL reaction within 10 min, or 8 copies within 8 min) visual detection of SARS-CoV-2 RNA spiked samples, as well as clinical saliva and nasopharyngeal swabs in VTM or water, on lateral flow devices. The ssRPA method promises rapid, sensitive, and accessible RNA detection to facilitate mass testing in the COVID-19 pandemic.

DNA performs diverse functional roles in biology, nanotechnology, and biotechnology, but current methods for autonomously synthesizing arbitrary single-stranded DNA are limited. Here, we introduce the concept of Primer Exchange Reaction (PER) cascades, which grow nascent single-stranded DNA with user-specified sequences following prescribed reaction pathways. PER synthesis happens in a programmable, autonomous, in situ, and environmentally responsive fashion, providing a platform for engineering molecular circuits and devices with a wide range of sensing, monitoring, recording, signal processing, and actuation capabilities. We experimentally demonstrate a nanodevice that transduces the detection of a trigger RNA into the production of a DNAzyme that degrades an independent RNA substrate, a signal amplifier that conditionally synthesizes long fluorescent strands only in the presence of a particular RNA signal, molecular computing circuits that evaluate logic (AND, OR, NOT) combinations of RNA inputs, and a temporal molecular event recorder that records in the PER transcript the order in which distinct RNA inputs are sequentially detected., Graphical Abstract

There is increasing demand for single-stranded DNA (ssDNA) of lengths >200 nucleotides (nt) in synthetic biology, biological imaging and bionanotechnology. Existing methods to produce high-purity long ssDNA face limitations in scalability, complexity of protocol steps and/or yield. We present a rapid, high-yielding and user-friendly method for in vitro production of high-purity ssDNA with lengths up to at least seven kilobases. Polymerase chain reaction (PCR) with a forward primer bearing a methanol-responsive polymer generates a tagged amplicon that enables selective precipitation of the modified strand under denaturing conditions. We demonstrate that ssDNA is recoverable in ∼40–50 min (time after PCR) with >70% yield with respect to the input PCR amplicon, or up to 70 pmol per 100 μl PCR reaction. We demonstrate that the recovered ssDNA can be used for CRISPR/Cas9 homology directed repair in human cells, DNA-origami folding and fluorescent in-situ hybridization.

We present a rapid, scalable, user-friendly method for in vitro production of high-purity single-stranded DNA (ssDNA) ranging from 89–3315 nucleotides in length. PCR with a forward primer bearing a methanol-responsive polymer generates a tagged amplicon that enables selective precipitation of the modified strand under denaturing conditions. We demonstrate that the recovered ssDNA can be used for CRISPR/Cas9 homology-directed repair in human cells, DNA-origami folding, and fluorescent in situ hybridization.

SUMMARYFluorescentin situhybridization (FISH) reveals the abun-dance and positioning of nucleic acid sequences in fixed sam-ples and can be combined with cell segmentation to produce a powerful single cell gene expression assay. However, it re-mains difficult to label more than a few targets and to visu-alize nucleic acids in environments such as thick tissue sam-ples using conventional FISH technologies. Recently, meth-ods have been developed for multiplexed amplification of FISH signals, yet it remains challenging to achieve high lev-els of simultaneous multiplexing combined with high sam-pling efficiency and simple workflows. Here, we introduce signal amplification by exchange reaction (SABER), which endows oligo-based FISH probes with long, single-stranded DNA concatemers that serve as targets for sensitive fluores-cent detection. We establish that SABER effectively ampli-fies the signal of probes targeting nucleic acids in fixed cells and tissues, can be deployed against at least 17 targets si-multaneously, and detects mRNAs with high efficiency. As a demonstration of the utility of SABER in assays involv-ing genetic manipulations, we apply multiplexed FISH of reporters and cell type markers to the identification of en-hancers with cell type-specific activity in the mouse retina. SABER represents a simple and versatile molecular toolkit to allow rapid and cost effective multiplexed imaging.

Chromosome organization is crucial for genome function. Here, we present a method for visualizing chromosomal DNA at super-resolution and then integrating Hi-C data to produce three-dimensional models of chromosome organization. Using the super-resolution microscopy methods of OligoSTORM and OligoDNA-PAINT, we trace 8 megabases of human chromosome 19, visualizing structures ranging in size from a few kilobases to over a megabase. Focusing on chromosomal regions that contribute to compartments, we discover distinct structures that, in spite of considerable variability, can predict whether such regions correspond to active (A-type) or inactive (B-type) compartments. Imaging through the depths of entire nuclei, we capture pairs of homologous regions in diploid cells, obtaining evidence that maternal and paternal homologous regions can be differentially organized. Finally, using restraint-based modeling to integrate imaging and Hi-C data, we implement a method–integrative modeling of genomic regions (IMGR)–to increase the genomic resolution of our traces to 10 kb., Author summary Questions regarding the impact of chromosome structure on genome function are focusing increasingly on the manner in which chromosomes are organized within the nucleus. In fact, studies of processes as diverse as gene activation and repression as well as genome repair and stability are all querying how the 3D organization of chromosomal DNA may be a major player. Here, we apply our strategy for tracing chromosomes at super-resolution, traversing over 8 megabases of human chromosome 19 while visualizing genomic features ranging in size from kilobases to megabases. This technology has enabled exploration of the physical nature of a genomic feature called the compartment; compartments are widely hypothesized to reflect the partitioning of genomes into relatively more and less active regions. Excitingly, we find that compartments are, indeed, physical structures, that they are sometimes distinct and other times entangled. We also find that the maternally-derived and the paternally-derived homologous regions can differ more than would be expected by chance. Finally, by integrating image data with information regarding the frequency with which genomic segments contact each other, we produce a 3D model of how the 8 megabases we have imaged may be organized within a single nucleus, achieving 10 kb genomic resolution.

Significance FISH enables researchers to visualize the subcellular distribution of RNA and DNA molecules in individual cells. The recent development of FISH methods employing probes composed of synthetic DNA oligonucleotides (oligos) allows researchers to tightly control aspects of probe design such as binding energy and genomic specificity. Although oligo FISH probes are central to many recently developed massively multiplexed and superresolution imaging methods, no dedicated computational utility exists to facilitate the design of such probes on the genome-wide scale. Here, we introduce a streamlined pipeline for the rapid, genome-scale design of oligo FISH probes and validate our approach by using conventional and superresolution imaging. Our method provides a framework with which to design oligo-based hybridization experiments., Oligonucleotide (oligo)-based FISH has emerged as an important tool for the study of chromosome organization and gene expression and has been empowered by the commercial availability of highly complex pools of oligos. However, a dedicated bioinformatic design utility has yet to be created specifically for the purpose of identifying optimal oligo FISH probe sequences on the genome-wide scale. Here, we introduce OligoMiner, a rapid and robust computational pipeline for the genome-scale design of oligo FISH probes that affords the scientist exact control over the parameters of each probe. Our streamlined method uses standard bioinformatic file formats, allowing users to seamlessly integrate new and existing utilities into the pipeline as desired, and introduces a method for evaluating the specificity of each probe molecule that connects simulated hybridization energetics to rapidly generated sequence alignments using supervised machine learning. We demonstrate the scalability of our approach by performing genome-scale probe discovery in numerous model organism genomes and showcase the performance of the resulting probes with diffraction-limited and single-molecule superresolution imaging of chromosomal and RNA targets. We anticipate that this pipeline will make the FISH probe design process much more accessible and will more broadly facilitate the design of pools of hybridization probes for a variety of applications.

We propose a new fabrication technique for a TiNi tube-like device via a Ni-coated Ti wire. The Ni-coated Ti wire was wound on to a cylindrical mandrel. A subsequent heat-treatment, which was heated at 1173 K for various times in vacuum, was carried out. Observations of X-ray diffractometry and scanning electron microscopy show that TiNi compounds formed in the heat-treated devices. An endothermic peak and an exothermic peak in differential scanning calorimetry diagram were observed on the heating and cooling process, respectively. The device heat-treated at 1173K for 28.8ks demonstrates a good shape memory motion.

Oligonucleotide (oligo)-based fluorescence in situ hybridization (FISH) has emerged as an important tool for the study of chromosome organization and gene expression and has been empowered by the commercial availability of highly complex pools of oligos. However, a dedicated bioinformatic design utility has yet to be created specifically for the purpose of identifying optimal oligo FISH probe sequences on the genome-wide scale. Here, we introduce OligoMiner, a rapid and robust computational pipeline for the genome-scale design of oligo FISH probes that affords the scientist exact control over the parameters of each probe. Our streamlined method uses standard bioinformatic file formats, allowing users to seamlessly integrate existing and new utilities into the pipeline as desired, and introduces a novel method for evaluating the specificity of each probe molecule that connects simulated hybridization energetics to rapidly generated sequence alignments using supervised learning. We demonstrate the scalability of our approach by performing genome-scale probe discovery in numerous model organism genomes and showcase the performance of the resulting probes with both diffraction-limited and single-molecule super-resolution imaging of chromosomal and RNA targets. We anticipate this pipeline will make the FISH probe design process much more accessible and will more broadly facilitate the design of pools of hybridization probes for a variety of applications.

Inductive proximity sensors are noncontact sensing devices used to detect the approach of a target by an increase in coil resistance due to eddy current loss. Extending the operating distance of these sensors is demanded. In this paper, we propose the use of a magnetoplated wire (MPW) as a sensing coil. The MPW is a copper wire, whose circumference is plated with a magnetic thin film. We analyze the impedance of a proximity sensor using a copper wire (COW) and MPW coils by a finite element method. The use of the MPW results in a decrease in AC resistance due to the proximity effect, an increase in inductance, and the generation of a higher flux than when the COW is used. Therefore, it is possible to increase the quality factor Q of the MPW coil. As a result, the operating distances of the MPW and COW coils are 5.0 and 3.8 mm, respectively. The operating distance of the MPW coil is 1.3-fold that of the COW coil., Article, IEEE TRANSACTIONS ON MAGNETICS. 45(10):4463-4466 (2009)

Background Differentiating between acute cellular rejection (ACR) and recurrent hepatitis C virus after liver transplantation in hepatitis C virus–positive patients is difficult, but vital for preventing graft loss. Methods The blood eosinophil counts 3 days before or on the day of biopsy were retrospectively reviewed to evaluate their value for predicting ACR in 91 biopsy samples from 45 patients. Results Eosinophil counts on the day of biopsy were significantly higher in the ACR group (n = 20) than in the non-ACR (n = 71) group, although the difference was negligible 3 days before the biopsy. A relative eosinophil count of 2% or an absolute eosinophil count of 200 cells/mm 3 predicted ACR with a specificity of 94% or 96%, respectively. Conclusions Blood eosinophil count on the day of biopsy can be helpful in the diagnosis of ACR in patients who underwent living donor liver transplantation for hepatitis C virus–related cirrhosis.

Two new bipyridine derivative ligands with an extended π electron system and a triple hydrogen bond group, 2,4-diaminopyrimido[5,6-b]dipyrido[2,3-f:2’,3’-h]quinoxaline (DAPQ) and 2,4(1H,3H)-pyrimidinedion[5,6-b]dipyrido[2,3-f:2’3’-h]quinoxaline (PDPQ), were synthesized in order to construct high-performance Ru(II) complexes. The two Ru(II) complexes composed of dapq or pdpq and two 2,2’-bipyridine (BPY) ligands showed characteristic luminescent spectra with a peak maximum at ca. 610 nm. The octahedral Ru(II) complexes with a D-A-D (D: proton donor; A: proton acceptor) type triple hydrogen bond indicated intense luminescence in comparison with the corresponding Ru(II) complex composed of three BPY ligands. When the triple hydrogen bond was formed with a Co(III) complex with the D-A-D type hydrogen bonding group, the luminescence was quenched. This result was explained in terms of an energy transfer from an excited Ru(II) complex to the Co(III) complex.

The relationship between the crack nucleation and stress-induced martensitic transformation in the retained massive austenites (RM-y's) of austempered ductile irons (ADIs) was examined in detail by carrying out tensile tests and scanning electron microscope (SEM) observations for an ADI material. The SEM observations revealed that cracks were not nucleated in the peripheral regions of graphite nodules but were nucleated in the RM-y's. Surface relief due to stress-induced martensitic transformation was observed near the cracks in the RM-y's, and it was also observed in the RM-y's in which cracks were not visible. For this reason, the cracks were concluded to be nucleated mainly in the RM-y's subjected to stress-induced martensitic transformation.

We report on magnetic domain observations using in-situ Lorentz microscopy of the ferromagnetic shape memory alloys of the type Ni 2 MnGa and Co 2 NiGa. The domain configurations are analyzed by means of the Transport-of-Intensity phase reconstruction method.

TEM observations and transformation characteristics of Co 2 Ni 1-x Ga 1+x ferromagnetic shape memory alloys will be presented. The dependence of the martensitic transformation start temperatures on the valance-electron atom ratio is identical to that of NiMnGa alloys. Optical microstructures show typical self-accommodated structures. The domain boundaries are straight indicating only elastic distortions in the product phase. High-density striations are observed in the TEM bright field images of the martensite-phase. Selected area electron diffraction patterns and TEM dark field images revealed that they are thin twin plates. Tweed or striated contrast is observed in the TEM bright field images of the parent phase at temperatures about 70 K higher than the M s temperature.

A 67-year-old man with AML, who had a 21-year history of psoriasis without remission, received a reduced-intensity transplantation from an HLA-identical sibling. The preparative regimen consisted of busulfan and fludarabine. Graft-versus-host-disease (GVHD) prophylaxis was cyclosporine and methotrexate. Psoriasis was completely resolved on day 18. The subsequent clinical course was uneventful until day 42, when psoriasis recurred at the same sites as before RIST. Peripheral blood examined on day 63 showed mixed chimerism with 54% recipient type. Cyclosporine was rapidly tapered off over the next 2 weeks. On day 90, 100% donor-type chimerism was confirmed. Subsequently, psoriasis improved simultaneously with the occurrence of mucositis and rash as a manifestation of GVHD. Scattered erythematous patches of psoriasis disappeared again by day 105. We initiated 0.5 mg/kg prednisolone on day 119, and resumed cyclosporine on day 133. At 7 months after RIST, he still suffers from chronic GVHD, but his psoriasis remains in remission for the first time in 21 years. The anti-psoriasis effect of the conditioning is mild and transient, while the graft-versus-autoimmunity effect, related to the induction of complete donor-type chimerism and GVHD, is more profound and persisting. A graft-versus-autoimmunity effect lies in the delicate balance between alloimmunity and immunosuppressant used for GVHD prophylaxis/treatment.

The transformation characteristics of CoNiGa ribbons resemble those of bulk alloys. However, the transformation temperatures in the ribbons are higher than those of the bulk suggesting stress-induced martensites. TEM observations reveal arch typical twins and precursor tweed structures. The twins can be wavy suggesting a small boundary energy.

Interleukin (IL)-12 and IL-18 are major interferon (IFN)-gamma-inducing factors that collaborate with each other. The present study was conducted to determine the distinct roles of IL-12 and IL-18 in the development of dextran sulphate sodium (DSS) colitis in mice.Colitis was induced in IL-12p35(-/-), IL-18(-/-), IL-18 receptor(-/-) and control mice with DSS. Clinical and histopathological analysis was conducted using survival rate, weight loss score, diarrhoea score, bloody stool score and histological score. In addition, cytokine production by lamina propria mononuclear cells (LPMCs) was examined using the specific enzyme-linked immunoassay.IL-12p35(-/-) mice developed only a mild disease associated with no lethality and few histopathological abnormalities. In contrast, IL-18(-/-) and IL-18R(-/-) mice developed more severe colitis associated with high lethality and more histopathological abnormalities compared with control mice. LPMCs from DSS-fed IL-18(-/-) mice produced significantly higher amounts of IFN-gamma, while LPMCs from DSS-fed IL-12(-/-) mice produced lower amounts of IFN-gamma and tumour necrosis factor (TNF)-alpha compared with control mice.These results suggest that IL-18 might function with manners different from IL-12 at some pathological conditions in the development of colitis.

Disseminated aspergillus infection has a poor prognosis, but few reports have been published on extra-pulmonary involvement in aspergillosis. We reviewed 107 autopsy records of patients with invasive aspergillosis. Fifty-five patients had extra-pulmonary aspergillosis. Organs involved included heart, kidney, central nervous system, gastrointestinal tract, spleen, liver, thyroid gland and pancreas. Extra-pulmonary aspergillosis produces different manifestations according to involved organs. Risk factors associated with dissemination included cytotoxic chemotherapy within a month of death (P=0.0087). Lack of response to empiric or preemptive treatment of amphotericin B predicted IA dissemination (P=0.0328). To improve prognosis of IA, it is important to recognize clinical features of extra-pulmonary aspergillosis and to institute the aggressive anti-fungal treatment.

Relation between tensile deformation behavior and microstructure in variously aged Ti–49.7 at%Ni–1.3 at%Co shape memory alloys has been investigated. Stress-strain curves for the alloys aged at 623 K and 723 K for 1.8 ks were of a work-hardening type, but those for the alloys aged at the two temperatures over 28.8 ks were nearly of a constant-stress type, as for binary Ti–51 at%Ni aged alloys. Lenticular precipitates were observed in both the 623 K and 723 K aged alloys, and the distance among the precipitates increased with increasing aging temperature and period, as well as the size of the precipitates. The lenticular precipitates were identified to be of the composition of Ti3(Ni, Co)4 from an EDX analysis. Based on these observations, the constant-stress type stress-strain behavior for the alloys aged over 28.8 ks was attributed to some composition change accompanied with the aging progress by which Ti:(Ni+Co) composition ratio in the matrix of the Ti–Ni–Co alloys approached 1:1, as in the equi-atomic Ti–Ni binary alloys.

Transformation characteristics, microstructures and tensile properties of a Ti-49.7at.%Ni-1.38at.%Co alloy have been investigated as a function of aging temperature and period. After a solution-treatment, the alloy was aged at 623 K and 723 K for 1.8, 14.4, 115.2 and 230.4 ks in argon atmosphere, followed by water cooling. Microstructures of the aged alloys were observed by using a transmission electron microscope operated at 200 kV. Fine Ti 3 Ni 4 precipitates were observed in all the 623 K and 723 K aged alloys, and their size increased with increasing aging temperature and time. For the same aging time, the number of Ti 3 Ni 4 precipitates per unit area for the 623 K aged alloy was larger than that for the 723 K aged alloy. The R-phase products were also observed in the aged alloys at 623 K and 723 K for 115.2 and 230.4 ks. Tensile properties of the aged alloys at 623 K and 723 K for 1.8 ks were examined at temperatures higher than A f ' by 15 K with tensile speed of 8.3×10 -6 m/s. Critical stress for inducing B19' martensites, σ M , of the aged alloy at 723 K for 1.8 ks was nearly equal to the aged alloy at 623 K for 1.8 ks, however, elongation at tensile fracture point of the former alloy was about 2 times longer than that of the latter one. These tensile properties were the same as those previously observed by the present authors, and they seemed to be interpreted by considering that the stress induced martensits were not developed in the aged alloy at 623 K for 1.8 ks although they were done in the aged alloy at 723 K for 1.8 ks, because the number of Ti 3 Ni 4 precipitates per unit area were larger in the former alloy than the latter alloy, as verified by TEM observation.

We have performed a measurement of the K + !� + � 0 decay and have observed 2×10 4 events. The best fit to the decay spectrum gives a branching ratio for direct photon emission of (4.7 ± 0.8 ± 0.3) × 10 6 in the � + kinetic energy region of 55 to 90 MeV and requires no component due to interference with inner bremsstrahlung.

We report the first measurement of a structure-dependent component in the decay ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\nu}}_{\ensuremath{\mu}}\ensuremath{\gamma}$. Using the kinematic region where the muon kinetic energy is greater than 137 MeV and the photon energy is greater than 90 MeV, we find that the absolute value of the sum of the vector and axial-vector form factors is $|{F}_{V}{+F}_{A}|\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.165\ifmmode\pm\else\textpm\fi{}0.007\ifmmode\pm\else\textpm\fi{}0.011$. This corresponds to a branching ratio of $B({\mathrm{SD}}^{+})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}(1.33\ifmmode\pm\else\textpm\fi{}0.12\ifmmode\pm\else\textpm\fi{}0.18)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$. We also set the limit $\ensuremath{-}0.04l{F}_{V}{\ensuremath{-}F}_{A}l0.24$ at $90%$ C.L.

A simulation for the Co(NO 3 ) 2 –Na 2 CO 3 –H 2 O system based on a thermodynamic model was proposed which predicts possible equilibrium states attained among gas, aqueous and solid phases under isothermal and isobaric conditions. Various chemical species such as CoOH + the cobalt complex, carbonate species in aqueous solution, precipitate of basic cobalt carbonate and CO 2 gas were taken into account. By using the Debye–Huckel formula for the activity coefficients of ionic species, apparent equilibrium constants of chemical reactions were well evaluated. A thermodynamic model was constructed by combining mass action law, mass balance, and charge balance equations together with equilibrium conditions among different phases. Simulation was carried out to compute concentrations of various chemical species in aqueous solution, amount of precipitate, and pressure of CO 2 . In order to examine the validity of the thermodynamic model, the computed pH values were compared with experimental results and a relatively good agreement between them was obtained.

OBJECTIVE—To evaluate changes in coronary artery spasticity in patients with vasospastic angina who had been stable for years under continuous drug treatment. METHODS—Follow up coronary angiography was performed under intracoronary ergonovine provocation in 27 well controlled patients with vasospastic angina and no organic stenosis; the tests were done > 24 months after the initial coronary angiography, in which occlusive spasm had been induced by the same regimen of ergonovine provocation. RESULTS—The mean (SD) follow up period was 47.2 (21.6) months. All patients had been free from angina attack for more than 24 months under treatment with antianginal drugs. During this follow up period, organic stenosis developed in only one case. Occlusive spasm was observed during follow up coronary angiography in 23 patients. Spasm with 90% narrowing was observed in three other patients, and diffuse significant narrowing was seen in the final patient. No significant difference was found in spasticity (p = 0.75) between the initial and the follow up tests. CONCLUSIONS—Repeated ergonovine provocation during coronary angiography after a controlled period of several years showed that coronary spasm remains inducible in most patients. Discontinuance of drug treatment during the remission from anginal attacks achieved by medication may put the patient at high risk. Keywords: vasospastic angina; ergonovine; angiography

The hydrolysis of cobalt ions in a fairly concentrated solution was studied based on a thermodynamic model. Cobalt solutions of 0.02, 0.05, 0.1 and 0.2 mol/dm3 were prepared and, by adding NaOH solution to the cobalt solution of given initial concentration, pH values were measured. Measurements were made under different experimental conditions as to the control of gas surrounding the apparatus and the water used in this experiment. These data were then analyzed using a thermodynamic model, in which it was assumed that only one kind of complex ion, CoOH+, contributes to the hydrolysis reaction and an apparent equilibrium constant of this hydrolysis reaction Kapp is an important parameter in this model. It was indicated that, in order to obtain a better agreement with the experimental data, a formula derived from a thermodynamic model should have been modified by adding a correction factor Capp. Computation was made by using this semi-empirical formula and a satisfactory agreement was obtained with the experimental data for various cobalt concentrations and for different experimental conditions as to the control of gas and the water used in this experiment.

An event consistent with the signature expected for the rare kaon decay ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ has been observed. In the pion momentum region examined, $211lPl230\mathrm{MeV}/c$, the backgrounds are estimated to contribute $0.08\ifmmode\pm\else\textpm\fi{}0.03$ events. If the event is due to ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$, the branching ratio is ${4.2}_{\ensuremath{-}3.5}^{+9.7}\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$.

This paper describes efficient transmission bandwidth management based on flexible channel assignment and effective grade of service (GOS) control methods for nongeostationary orbit mobile satellite service (NGSO MSS) networks. Our basic approach for the flexible channel assignment is to use linear programming (FLEXCA-LP), and to apply the column generation technique for further reduction of the total bandwidth requirement. These methods efficiently assign channels, taking account of moving spot beam coverage and dynamic traffic load variation for large-scale networks. The GOS is investigated for the channel assignment by FLEXCA-LP to make the GOS of ongoing calls better than that of fresh calls as stipulated in ITU-T Recommendations. We propose a few effective means to improve the results of FLEXCA-LP by reducing the disruption possibility of ongoing calls. One is to add channels utilizing a hysteresis concept. The others are effective use of GOS control techniques for NGSO MSS networks. These techniques are evaluated by a simulation study to identify promising techniques. Under time-variant conditions, we show that a reliable channel assignment plan is generated first by FLEXCA-LP considering the traffic load of fresh calls only and then by GOS control techniques to improve handover failure and call disruption rates.