EFFECTS OF MO, CR, AND V ADDITIONS ON TENSILE AND CHARPY IMPACT PROPERTIES OF API X80 PIPELINE STEELS

In this study, four API X80 pipeline steels were fabricated by varying Mo, Cr, and V additions, and their microstructures and crystallographic orientations were analyzed to investigate the effects of their alloying compositions on tensile properties and Charpy impact properties. Because additions of Mo and V promoted the formation of fine acicular ferrite (AF) and granular bainite (GB) while prohibiting the formation of coarse GB, they increased the strength and upper-shelf energy (USE) and decreased the energy transition temperature (ETT). The addition of Cr promoted the formation of coarse GB and hard secondary phases, thereby leading to an increased effective grain size, ETT, and strength, and a decreased USE. The addition of V resulted in a higher strength, a higher USE, a smaller effective grain size, and a lower ETT, because it promoted the formation of fine and homogeneous of AF and GB. The steel that contains 0.3 wt pct Mo and 0.06 wt pct V without Cr had the highest USE and the lowest ETT, because its microstructure was composed of fine AF and GB while its maintained excellent tensile properties.X1126sciescopu

General Argyres-Douglas Theory

We construct a large class of Argyres-Douglas type theories by compactifying six dimensional (2,0) A_N theory on a Riemann surface with irregular singularities. We give a complete classification for the choices of Riemann surface and the singularities. The Seiberg-Witten curve and scaling dimensions of the operator spectrum are worked out. Three dimensional mirror theory and the central charges a and c are also calculated for some subsets, etc. Our results greatly enlarge the landscape of N=2 superconformal field theory and in fact also include previous theories constructed using regular singularity on the sphere.Comment: 55 pages, 20 figures, minor revision and typos correcte

Symmetry energy of dense matter in holographic QCD

We study the nuclear symmetry energy of dense matter using holographic QCD. To this end, we consider two flavor branes with equal quark masses in a D4/D6/D6 model. We find that at all densities the symmetry energy monotonically increases. At small densities, it exhibits a power law behavior with the density, $E_{\rm sym} \sim \rho^{1/2}$.Comment: 9 pages, 3 figure

Holographic Hadrons in a Confining Finite Density Medium

We study a sector of the hadron spectrum in the presence of finite baryon density. We use a non-supersymmetric gravity dual to a confining guage theory which exhibits a running dilaton. The interaction of mesons with the finite density medium is encoded in the dual theory by a force balancing between flavor D7-branes and a baryon vertex provided by a wrapped D5-brane. When the current quark mass m_q is sufficiently large, the meson mass reduces, exhibiting an interesting spectral flow as we increase the baryon density while it has a more complicated behaviour for very small m_q.Comment: 34 pages, 20 figures, errors for some figures are fixe

Symmetry Energy and Universality classes of holographic QCD

We study nuclear symmetry energy of dense matter using holographic QCD. We calculate it in a various holographic QCD models and show that the scaling index of the symmetry energy in dense medium is almost invariant under the smooth deformation of the metric as well as the embedding shape of the probe brane. We find that the scaling index depends only on the dimensionality of the branes and space-time. Therefore the scaling index of the symmetry energy characterizes the universality classes of holographic QCD models. We suggest that the scaling index might be also related to the non-fermi liquid behavior of the interacting nucleons.Comment: 23 pages, 17 figure

Early rheumatoid arthritis is characterized by a distinct and transient synovial fluid cytokine profile of T cell and stromal cell origin

Pathological processes involved in the initiation of rheumatoid synovitis remain unclear. We undertook the present study to identify immune and stromal processes that are present soon after the clinical onset of rheumatoid arthritis ( RA) by assessing a panel of T cell, macrophage, and stromal cell related cytokines and chemokines in the synovial fluid of patients with early synovitis. Synovial fluid was aspirated from inflamed joints of patients with inflammatory arthritis of duration 3 months or less, whose outcomes were subsequently determined by follow up. For comparison, synovial fluid was aspirated from patients with acute crystal arthritis, established RA and osteoarthritis. Rheumatoid factor activity was blocked in the synovial fluid samples, and a panel of 23 cytokines and chemokines measured using a multiplex based system. Patients with early inflammatory arthritis who subsequently developed RA had a distinct but transient synovial fluid cytokine profile. The levels of a range of T cell, macrophage and stromal cell related cytokines ( e. g. IL-2, IL-4, IL-13, IL-17, IL-15, basic fibroblast growth factor and epidermal growth factor) were significantly elevated in these patients within 3 months after symptom onset, as compared with early arthritis patients who did not develop RA. In addition, this profile was no longer present in established RA. In contrast, patients with non-rheumatoid persistent synovitis exhibited elevated levels of interferon-gamma at initiation. Early synovitis destined to develop into RA is thus characterized by a distinct and transient synovial fluid cytokine profile. The cytokines present in the early rheumatoid lesion suggest that this response is likely to influence the microenvironment required for persistent RA

Understanding how excess lead iodide precursor improves halide perovskite solar cell performance

The presence of excess lead iodide in halide perovskites has been key for surpassing 20% photon-to-power conversion efficiency. To achieve even higher power conversion efficiencies, it is important to understand the role of remnant lead iodide in these perovskites. To that end, we explored the mechanism facilitating this effect by identifying the impact of excess lead iodide within the perovskite film on charge diffusion length, using electron-beam-induced current measurements, and on film formation properties, from grazing-incidence wide-angle X-ray scattering and high-resolution transmission electron microscopy. Based on our results, we propose that excess lead iodide in the perovskite precursors can reduce the halide vacancy concentration and lead to formation of azimuthal angle-oriented cubic alpha-perovskite crystals in-between 0 degrees and 90 degrees. We further identify a higher perovskite carrier concentration inside the nanostructured titanium dioxide layer than in the capping layer. These effects are consistent with enhanced lead iodide-rich perovskite solar cell performance and illustrate the role of lead iodide

Controlled Orientation of Active Sites in a Nanostructured Multienzyme Complex

Multistep cascade reactions in nature maximize reaction efficiency by co-assembling related enzymes. Such organization facilitates the processing of intermediates by downstream enzymes. Previously, the studies on multienzyme nanocomplexes assembled on DNA scaffolds demonstrated that closer interenzyme distance enhances the overall reaction efficiency. However, it remains unknown how the active site orientation controlled at nanoscale can have an effect on multienzyme reaction. Here, we show that controlled alignment of active sites promotes the multienzyme reaction efficiency. By genetic incorporation of a non-natural amino acid and two compatible bioorthogonal chemistries, we conjugated mannitol dehydrogenase to formate dehydrogenase with the defined active site arrangement with the residue-level accuracy. The study revealed that the multienzyme complex with the active sites directed towards each other exhibits four-fold higher relative efficiency enhancement in the cascade reaction and produces 60% more D-mannitol than the other complex with active sites directed away from each other.ope

Conjugated polyelectrolyte hole transport layer for inverted-type perovskite solar cells

Organic-inorganic hybrid perovskite materials offer the potential for realization of low-cost and flexible next-generation solar cells fabricated by low-temperature solution processing. Although efficiencies of perovskite solar cells have dramatically improved up to 19% within the past 5 years, there is still considerable room for further improvement in device efficiency and stability through development of novel materials and device architectures. Here we demonstrate that inverted-type perovskite solar cells with pH-neutral and low-temperature solution-processable conjugated polyelectrolyte as the hole transport layer (instead of acidic PEDOT:PSS) exhibit a device efficiency of over 12% and improved device stability in air. As an alternative to PEDOT: PSS, this work is the first report on the use of an organic hole transport material that enables the formation of uniform perovskite films with complete surface coverage and the demonstration of efficient, stable perovskite/fullerene planar heterojunction solar cellsopen4

Notch1 deficiency decreases hepatic lipid accumulation by induction of fatty acid oxidation

Notch signaling pathways modulate various cellular processes, including cell proliferation, differentiation, adhesion, and communication. Recent studies have demonstrated that Notch1 signaling also regulates hepatic glucose production and lipid synthesis. However, the effect of Notch1 signaling on hepatic lipid oxidation has not yet been directly investigated. To define the function of Notch1 signaling in hepatic lipid metabolism, wild type mice and Notch1 deficient antisense transgenic (NAS) mice were fed a high-fat diet. High-fat diet-fed NAS mice exhibited a marked reduction in hepatic triacylglycerol accumulation compared with wild type obese mice. The improved fatty liver was associated with an increased expression of hepatic genes involved in fatty acid oxidation. However, lipogenic genes were not differentially expressed in the NAS liver, suggesting lipolytic-specific regulatory effects by Notch1 signaling. Expression of fatty acid oxidative genes and the rate of fatty acid oxidation were also increased by inhibition of Notch1 signaling in HepG2 cells. In addition, similar regulatory effects on lipid accumulation were observed in adipocytes. Taken together, these data show that inhibition of Notch1 signaling can regulate the expression of fatty acid oxidation genes and may provide therapeutic strategies in obesity-induced hepatic steatosisopen0