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The DNA sequence of a single‐stranded and double‐stranded template was determined. The templates were sequenced using the chain termination method and cycle sequencing method and detected by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. The sequencing products were analyzed successfully without the laborious and expensive methods for removal of the template. Direct sequencing of the double‐stranded template was achieved with minimal post‐reaction purifications, which could be extremely important for mutation analysis and clinical diagnosis. A systematic study of the mechanisms and kinetics of sequencing reactions was also performed. The details of this analysis and directions for future improvements of the quality of sequencing are presented. © 1997 John Wiley & Sons, Ltd. This paper was produced under the auspices of the US Government and it is therefore not subject to copyright in the US

Summary. To evaluate Fas/FasL expression in hepatitis B virus‐related chronic liver disease, liver biopsies from 44 such cases were studied immunohistochemically. FasL was detected in the infiltrating lymphocytes and both FasL and Fas were found in the hepatocytes. The Fas and FasL‐positive cells were mostly found at the advancing edges of interphase hepatitis, and Fas/FasL expression was closely correlated with the inflammatory activity. Unexpectedly, FasL was also expressed in liver cirrhotic nodules, particularly in those with hepatocellular carcinoma with or without inflammation. These results suggest that the factors which induce hepatocyte transformation might also trigger FasL expression and promote FasL/Fas‐mediated apoptosis.

Migration of monocytes to sites of inflammation involves a series of attachments and detachments to extracellular matrix proteins. We examined the capacity of a chemokine, monocyte chemoattractant protein-1 (MCP-1), to regulate attachment of human monocytes to laminin, collagen I, collagen IV, or fibronectin. MCP-1 increased monocyte attachment to laminin in a dose- and time-dependent manner and stimulated a lesser increase to the other matrix proteins. Function-blocking monoclonal antibodies (MAbs) to the integrin beta 2-subunit (CD18), including Fab' fragments and alpha M (CD11b) blocked > 70% of attachment, whereas MAbs to the beta 1-integrin subunit reduced attachment by < 30%. This suggests that the CD11b/CD18 integrin is the predominant molecule involved in adhesion of MCP-1-stimulated monocytes to laminin. The association of CD11b with F-actin illustrated by confocal microscopy further supports this concept. In contrast, when monocytes were stimulated with the beta 1-stimulatory MAb TS2/16, monocyte adhesion to laminin occurred through beta 1-integrins. Thus MCP-1 can stimulate monocyte attachment to laminin, and this process is mediated through beta 2-integrins, principally CD11b/CD18.

According to the proposal developed by Fanget al. (1984, referred to as Paper I) on formation of large-scale structure in the Universe, we should expect that:(1)The distributions of quasars should be different from that of galaxies by no strong inhomogeneity on the scale of 10–100 Mpc.(2)The distributions of quasars withZ>2 andZ<2 should be different from each other with no large-scale structure in the former, and conversely in the latter.

Using the Fröhlich potential associated with realistic optical phonon modes in quantum well systems, the energy loss rates of hot electrons, holes, and electron–hole pairs are calculated, with special emphasis on the effects of carrier density, hot phonon population, quantum well width, and phonon dispersion on the hot-carrier relaxation process in quasi-two-dimensional systems.

What is the current state of Chinese architecture? What are the themes and ideas Chinese architects want to project in their work? What are the major issues of architecture in the context of the social, political and cultural conditions of contemporary China? In this article, J. F. Zhu, in. a critical observation on Chinese architecture in the 1980s and 90s, takes up these questions.

The complex salts [Et3NH][(μ-RS)(μ-CO)Fe2(CO)6] (1:  R = Et, t-Bu, Ph), prepared from Fe3(CO)12, RSH, and Et3N, react in situ with the triply bonded dimers [(η⁵-R‘C5H4)(CO)2M]2 (2:  M = Mo, W; R‘ = H, MeCO, MeO2C, EtO2C) followed by treatment with air to give the series of novel clusters (η⁵-R‘C5H4)(CO)2MoFe2(μ3-O)(μ-RS)(CO)6 (compound, R, R‘:  3a, Et, H; 3b, t-Bu, H; 3c, Et, MeCO; 3d, t-Bu, MeO2C; 3e, Ph, MeO2C; 3f, Et, EtO2C; 3g, t-Bu, EtO2C; 3h, Ph, EtO2C) in 26−37% yields and (η⁵-R‘C5H4)(CO)2WFe2(μ3-O)(μ-RS)(CO)6 (compound, R, R‘:  3i, Et, MeO2C; 3j, t-Bu, MeO2C; 3k, Et, EtO2C) in 12−17% yields. Single-crystal X-ray diffraction analyses of 3d and 3k confirmed that (i) these clusters consist of the M−S (M = Mo, W) edge-opened square-pyramidal cluster skeleton MFe2SO with the M atom occupying its apical position and the Fe2OS atoms constructing its pyramid base and (ii) clusters 3d and 3k are single isomers in which the t-Bu and Et groups are bonded to the bridged S atoms by an equatorial type of bond.

The blaR gene of Bacillus licheniformis encodes the signal transducer for induction of the class A beta-lactamase. The protein product, BlaR, has a hydrophilic carboxy region that binds beta-lactams and shows high sequence homology to the class D beta-lactamases, particularly the OXA-2 beta-lactamase of Salmonella typhimurium. The BlaR-beta-lactam complex is stable and may provide the continuing stimulus needed for the prolonged production of the enzyme.

The DRB family of human class II major histocompatibility complex (Mhc) loci is unusual in that individuals differ in the number and combination of genes (haplotypes) they carry. Indications are that both the allelic and haplotype polymorphisms of the DRB loci predate speciation. Searching for the evolutionary origins of these polymorphisms, we have sequenced five DRB clones isolated from a cDNA library of a pigtail macaque (Macaca nemestrina) B lymphocyte line. The clones represent five different genes which we designate Mane-DRB*01-Mane-DRB*05. The genes appears to be approximately equidistant from each other, so that allelic relationships between them cannot be established on the basis of the sequence data alone. If positions coding for the peptide-binding region of the class II beta chains are eliminated from sequence comparisons, the Mane-DRB genes appear to be most closely related to the human (HLA) DRB1 genes of the DRw52 group. We interpret this finding to indicate that the ancestral gene of the DRw52 group of human DRB1 alleles separated from the rest of the HLA-DRB1 alleles before the separation of the Old World monkeys (Cercopithecoidea) from the apes (Hominoidea) in the early Oligocene. After this separation, the ancestral DRB1 gene of the DRw52 group duplicated in the Old World monkey lineage to give rise to genes at three loci at least, while in the ape lineage this gene may have remained single and diverged into a number of alleles instead. These findings suggest that some of the polymorphism currently present at the DRB1 locus is greater than 35 Myr old.

A second regulatory locus (blaR1) required for the induction of beta-lactamase synthesis in Bacillus licheniformis 749 was cloned and sequenced. The gene was located on a 5.2-kilobase-pair SphI DNA fragment which also contained the beta-lactamase (blaP) and repressor (blaI) genes. Bacillus subtilis BD224 carrying these three genes synthesized beta-lactamase on exposure to cephalosporin C, whereas Escherichia coli HB101 carrying the genes did not show any detectable induction of the enzyme. An open reading frame of 1,803 bases was identified as the blaR1 gene by subcloning and DNA sequencing. The gene started 2 bases downstream of the termination codon of bla1 and was preceded by a putative Shine-Dalgarno sequence (AAGGA) with a spacing of 5 bases. The deduced blaR1 product (601 amino acids) had a molecular weight of 68,425. Five transmembrane regions were predicted from the hydrophobicity profile. The region around Phe-Ala-Pro-Ala-Ser-Thr-Tyr-Lys (amino acids 398 to 405), which appeared to be located outside the membrane, was homologous to the binding regions of penicillin-binding proteins, including the beta-lactamases. The segment of 22 amino acids from 400 to 421 showed more than 70% homology to the penicillin-binding region of PBP 2 of E. coli. The blaR1 gene encodes a potential penicillin receptor which is required for the induction of beta-lactamase in B. licheniformis 749.

Background: While the physical and chemical properties of airborne particulate matter (PM) have been extensively studied, their associated microbiome remains largely unexplored. Here, we performed a longitudinal metagenomic survey of 106 samples of airborne PM2.5and PM10in Beijing over a period of 6 months in 2012 and 2013, including those from several historically severe smog events. Results: We observed that the microbiome composition and functional potential were conserved between PM2.5and PM10, although considerable temporal variations existed. Among the airborne microorganisms, Propionibacterium acnes, Escherichia coli, Acinetobacter lwoffii, Lactobacillus amylovorus, and Lactobacillus reuteridominated, along with several viral species. We further identified an extensive repertoire of genes involved in antibiotic resistance and detoxification, including transporters, transpeptidases, and thioredoxins. Sample stratification based on Air Quality Index (AQI) demonstrated that many microbial species, including those associated with human, dog, and mouse feces, exhibit AQI-dependent incidence dynamics. The phylogenetic and functional diversity of air microbiome is comparable to those of soil and water environments, as its composition likely derives from a wide variety of sources. Conclusions: Airborne particulate matter accommodates rich and dynamic microbial communities, including a range of microbial elements that are associated with potential health consequences.

Ultra‐low frequency (ULF) waves can effectively accelerate ring current ions through drift‐bounce resonance. Conventional theories have been developed to understand this resonance since the dawn of the space age, which usually assume ULF waves are quasi‐steady in time. However, ULF waves would experience growth and damping stages in the real magnetosphere, which requires an adjustment of the conventional theories. Here, we attempt to reveal how ions respond to evolving ULF waves. By analyzing an event observed by Van Allen Probe A and reproducing the observations via simulation, we find the phase shift of ion flux oscillation across resonant pitch angles varies with time, when wave growth and damping cannot be neglected. As a result, the inclination angle of stripes in pitch angle spectrogram varies with time, causing “fishbone‐like” pitch angle structures. One should take into account such ion behaviors when considering the role of drift‐bounce resonance in the real magnetosphere. The responses of ring current ions to evolving ULF waves are observed by Van Allen Probe A and reproduced via simulationThe observed phase shift across resonant pitch angle changes with time, manifesting as increasingly inclined or vertical pitch angle stripesSimulation suggests the growth and damping of ULF waves are responsible for the time‐varying phase shift

A novel chiral monodentate spiro phenylphospholane ligand 4 was prepared from a readily accessible, enantiomerically pure 1,1‘-spirobiindane-7,7‘-diol in high yield. This ligand has proven to be efficient for Pd-catalyzed enantioselective allylation of aldehydes with allylic alcohols. Aromatic, heteroaromatic, and aliphatic aldehydes gave homoallylic alcohols in good enantioselectivities (up to 83% ee) and excellent anti diastereoselectivities (up to 99:1 dr).

A novel flavonoid diglycoside, 5,6,7,4‘-tetrahydroxyflavonol 3-O-rutinoside (1), and a previously known compound, kaempferol 3-O-neohesperidoside (2), were isolated from an ethyl acetate extract of Daphniphyllum calycinum leaves that showed significant activity in a 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical assay. The structure of 1 was elucidated by a combination of spectroscopic methods, and compounds 1 and 2 were found to be moderately active as antioxidants in the DPPH assay.

Nonlinear I–V characteristics of YBa2Cu3Oy epitaxial film at different temperatures in a magnetic field of up to 5T and angles between the direction of the field and the a–b plane of 0°, 30°, 45°, 60°, and 90° were measured. We find that there are the vortex glass phase and vortex liquid phase in the mixed state. The flux creep exists in the vortex glass phase, and it obviously appears in the area around the boundary between the vortex glass phase and the vortex liquid phase.

In order to improve the robustness of holographic watermarking, we propose a watermarking algorithm combining wavelet transform (DWT) and scale-invariant feature transform (SIFT). And neural network model is applied to digital watermarking technology. Firstly, the watermark image is transformed by Fresnel diffraction to generate hologram, which is divided into 16 x 16 blocks. And wavelet transform is carried out on each block to obtain the low-frequency information. Then, the feature points of the carrier image are extracted by SIFT, and the 16 x 16 blocks around the feature points are selected as the embedding areas to realize the embedding of the watermark.Finally, the random coordinates are taken as the input data of the neural network model, and the embedded position coordinates are taken as the output data of the neural network model. The relationship model between coordinates is constructed to achieve the confidentiality of the embedded position. Experimental results show that the watermarking algorithm has good robustness and visibility under the premise of ensuring image quality.

Dynamic aging precipitation of Mg17Al12 phases in AZ80 magnesium alloy was studied by multi-directional forging (MDF) with decreasing temperatures from 410 to 300 degC. The results show that the morphology of the dynamically precipitated b-Mg17Al12 phases (formed during forging process) exhibited granular shape. During the multi-directional forging process, the inhomogeneous dynamic precipitation of the b-Mg17Al12 phases result in the coexistence of the fine grains (with many granular Mg17Al12 phases) and coarse grains (without Mg17Al12 phases) in the samples. The fine grains (with many granular Mg17Al12 phases) area expands with the decreasing of final forging temperature. The inhomogenous Al content distribution in the Mg matrix leads to the non-uniform dynamic precipitation of the Mg17Al12 phase. These Mg17Al12 phase retards the growth of the DRX grains, which in turns results in the formation fine grains area during the during the MDF process with temperature decreasing.

This paper presents integration challenges associated with M1 to CT connection in Ultra low-k (ULK) Back-End-Of-Line (BEOL) interconnects for 40nm node and beyond. In advance IC fabrication, porous dielectric materials, such as BDII (related dielectric constant k about 2.5), are commonly used as insulator in copper interconnects for RC delay reduction. But the material of inter-dielectric layer is still high density SiO2-based. Hence, the difference in materials of PMD and IMD would potentially induce mismatch of physical properties of the two types of dielectric and cause deterioration of M1 to Contact connection, which would further impact product yield by contact open or other issues. Cross section pictures of failing M1 to CT connection were exhibited with a special spacer profile and investigated to illustrate the phenomenon. Solutions were proposed, through optimization of Etch, Wet clean and CMP to improve process window. Layout optimization is also suggested as OPC and DFM solution for related layers. Some of the solutions were examined by experiments with 40nm BEOL test masks. Results of physical and electric characterization were presented and discussed.

A two-dimensional lattice Boltzmann method (LBM)-cellular automaton (CA) model is developed for the simulation of dendritic growth and bubble formation during alloy solidification. In the model, a kinetic LBM, which describes flow dynamics through the evolution of distribution functions of moving pseudo-particles, is adopted to numerically solve the gas-liquid two-phase flow based on the Shan-Chen multiphase scheme. The kinetics of dendritic growth is determined according to a local solute equilibrium approach. The present model takes into account the effect of liquid-solid phase transformation on the nucleation and growth of bubbles. The interaction mechanism between dendrites and bubbles is also embedded in the model. The wettability of a bubble on a smooth solid surface is simulated. The simulated contact angles with various interaction coefficients agree well with the data calculated from an empirical formula derived from the Young's equation. The proposed model is applied to simulate dendritic growth and bubble formation under directional solidification conditions. The simulated results are compared with those observed experimentally during solidification of a transparent organic material. The simulation results reveal some dynamic features of bubble nucleation, growth, and motion, as well as the interaction between the dendritic growth and bubble formation during solidification.

A quantitative phase-field (PF) model with an anti-trapping current (ATC) is developed to simulate the dendritic growth with two-sided diffusion. The asymptotic analysis is performed at the second-order for the PF equations coupled with nonlinear thermodynamic properties and an ATC term under the equal chemical potential condition. The PF mobility and ATC are derived based on the asymptotic analysis in the thin interface limit, and the solute drag model. Then the model is reduced to the dilute solution limit for dendrite solidification in binary alloys. The test of convergence with respect to the interface width exhibits an excellent convergent behavior of the proposed model. The performance of the model is then validated by the comparison of PF simulations to the predictions of the Gibbs-Thomson relation, and of the linearized solvability theory, for the isothermal dendritic growth of an Fe-1.5mol.%C alloy. The results demonstrate quantitative capabilities of the model that effectively suppresses the abnormal solute trapping effect when the interface is taken artificially wide. It is also found that the present model can quantitatively describe dendrite growth with various solid diffusivities, ranging from the case with one-sided diffusion to the symmetrical model.

To develop strategies for modifying the enameling steel chemical composition and processing to minimize yield strength reduction during the enamel-fire anneal (EFA), the reasons for yield strength reduction of a high strength cold rolled enameling steel were studied by combining experiments and thermodynamic calculations. The yield strength reductions were evaluated from the primary strengthening mechanism using existing empirical relationships that relate microstructural parameters to yield strength. The results show that yield strength reductions resulted primarily from an increase in grain size and a decrease in dislocation density. The EFA appeared to have a negligible effect on the solubilities of Mn, Si, and P, and the solubilities are nearly equal to the bulk concentrations. On the other hand, the elements C and N are nearly completely tied up as precipitates in the form of cementite and AlN. Thus, they have a negligible contribution to solid solution strengthening.

Effect of Mg alloying in Cu with pretreatments on corrosion behavior of Cu was studied, which was compared with that of a CuAl alloy. It was found that, at 673Kunder oxygen pressure of 0.1MPa, although the corrosion resistance of CuMg alloy was evidently improved in comparison with that of pure Cu, it was worse than that of CuAl alloy. Three possible reasons were: (i) Cu atoms were incorporated into the MgO surface layer. (ii) Fissures were produced in MgO layer. (iii) The adherence of MgO surface layer on Cu was poor. The first one could be due to formation of a new intermetallic phase of MgCu2on the surface of Cu sample during the formation of MgO surface layers, while the latter two were attributed to low Pilling-Bedworth ratio of Mg-O system smaller than 1.

Relict sutures from colliding continents, regions characterized by a ‘young’ Moho, layering and faulting throughout the crust, mid-crustal magma traps, and seismic ‘bright spots’ which suggest deep crustal fluids are among recent COCORP findings. In addition, new studies of signal penetration, noise mitigation, recording geometry, and coherency filtering have yielded better understanding of, and substantial improvements in, data quality. Amplitude anomalies, or ‘bright spots’, in the Basin and Range may be due to magma at mid-crustal levels; in one case, a normal fault appears to link the deep magma with young surface volcanics. Another bright spot, 15 km deep in southeastern Georgia, has a flat geometry that suggests a gas/liquid interface, perhaps within fluids underthrust along an Appalachian suture. The Moho continues to appear relatively undisturbed in many regions of past deformation, suggesting that its formation post-dates these major tectonic episodes. The diversity of reflection patterns from the U.S. Cordillera casts further doubt on the generality of the common model of a reflective, layered lower crust underlying a transparent upper crust.