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The ability to control network dynamics is essential for ensuring desirable functionality of many technological, biological, and social systems. Such systems often consist of a large number of network elements, and controlling large-scale networks remains challenging because the computation and communication requirements increase prohibitively fast with network size. Here, we introduce a notion of network locality that can be exploited to make the control of networks scalable, even when the dynamics are nonlinear. We show that network locality is captured by an information metric and is almost universally observed across real and model networks. In localized networks, the optimal control actions and system responses are both shown to be necessarily concentrated in small neighborhoods induced by the information metric. This allows us to develop localized algorithms for determining network controllability and optimizing the placement of driver nodes. This also allows us to develop a localized algorithm for designing local feedback controllers that approach the performance of the corresponding best global controllers, while incurring a computational cost orders-of-magnitude lower. We validate the locality, performance, and efficiency of the algorithms in Kuramoto oscillator networks, as well as three large empirical networks: synchronization dynamics in the Eastern US power grid, epidemic spreading mediated by the global airtransportation network, and Alzheimer's disease dynamics in a human brain network. Taken together, our results establish that large networks can be controlled with computation and communication costs comparable to those for small networks. [ABSTRACT FROM AUTHOR]

Using Langevin dynamics simulations, the response of neutral polymer brushes with charged terminal monomers to external electric fields has been investigated. The external electric field is equivalent to the field generated by the opposite surface charges on two parallel electrodes. The effects of charge valence of terminal monomers on the structure of double layers and overall charge balance near the two electrodes were examined. Using the charge density distributions obtained from simulations, the total electric field normal to the electrodes was calculated by numerically solving the Poisson equation. Under external electric fields, the total electric field across the two electrodes is highly nonuniform and in certain regions within the brush, the total electric field nearly vanishes. The probability distribution of electric force acting on one charged terminal monomer was obtained from simulations and how it affects the probability density distribution of terminal monomers was analyzed. The response of polymer brushes with charged terminal monomers to a strongly stretching external electric field was compared with that of uniformly charged polymer brushes. [ABSTRACT FROM AUTHOR]

This study addresses an attitude tracking problem for a rigid spacecraft with bounded external disturbances. Attitude dynamics of the rigid spacecraft is modelled by a unit quaternion for global representation. Based on this representation, a novel continuous controller is proposed based on the full-order terminal sliding mode method. The finite-time stability of the closed-loop system is assured by Lyapunov and homogeneous finite-time stability theorems. Moreover, the singularity term in the terminal sliding surface is compensated by an identical item in the feedback control law, and this makes the closed-loop system trajectories converge to the equilibrium in finite-time, and hence a high precision is obtained. Finally, simulation results are presented to illustrate the effectiveness of the proposed controller. [ABSTRACT FROM AUTHOR]

Tremella fuciformis polysaccharide (TFPS), which is the extract of Tremella fuciformis Berk, has previously been demonstrated to exhibit potent anti-oxidative, anti-inflammatory and anti-aging effects. However, the mechanisms underlying these protective and therapeutic effects remain to be elucidated. The aim of the present study was to investigate the protective effects of TFPS on hydrogen peroxide-induced injury of human skin fibroblasts and to elucidate the aforementioned underlying mechanisms. A hydrogen peroxide-induced human skin fibroblast injury model was firstly established. MTT and reactive oxygen species (ROS) production assays, in addition to terminal deoxynucleotidyl transferase dUTP nick end labeling, reverse transcription-quantitative polymerase chain reaction and western blotting, were performed to investigate the protective effects of TFPS. Hydrogen peroxide decreased human skin fibroblast viability with a concurrent increase in ROS generation and cell apoptosis. Treatment with 0-400 µg/ml TFPS alone for up to 48 h did not result in alteration in cell viability. Notably, TFPS pre-treatment reduced oxidative stress and cell apoptosis in hydrogen peroxide-treated skin fibroblasts. In addition, there was profound inhibition of p16, p21, p53 and caspase-3 expression, and activation of extracellular-signal regulated kinase and Akt serine/threonine kinase 1, following TFPS pre-treatment. Furthermore, it was revealed that TFPS additionally protected fibroblasts via the upregulation of SIRT1 expression, and this was abrogated by the SIRT1 inhibitor niacinamide. These results indicated that TFPS alleviated hydrogen peroxide-induced oxidative stress and apoptosis in skin fibroblasts via upregulation of SIRT1 expression, indicating that TFPS may act as a potential therapeutic agent for oxidative-stress-associated skin diseases and aging. [ABSTRACT FROM AUTHOR]

Superconducting thin films have been a focal point for intensive research efforts since their reduced dimension allows for a wide variety of quantum phenomena. Many of these films, fabricated in UHV chambers, are highly vulnerable to air exposure, making it difficult to measure intrinsic superconducting properties such as zero resistance and perfect diamagnetism with ex situ experimental techniques. Previously, we developed a multifunctional scanning tunneling microscope (MSTM) containing in situ four-point probe (4PP) electrical transport measurement capability in addition to the usual STM capabilities [Ge et al., Rev. Sci. Instrum. 86, 053903 (2015)]. Here we improve thisMSTMvia development of both transmission and reflection two-coil mutual inductance techniques for in situ measurement of the diamagnetic response of a superconductor. This addition does not alter the original STM and 4PP functions of the MSTM. We demonstrate the performance of the two-coil mutual inductance setup on a 10-nm-thick NbN thin film grown on a Nb-doped SrTiO3(111) substrate. [ABSTRACT FROM AUTHOR]

The increasing consumption of regenerated cellulose, in particular the viscose fiber, has led to a significant development of dissolving pulps in the last decade. In this review paper, the current status of dissolving pulp with respects to raw materials, manufacturing processes, and some key issues are discussed. Non-wood materials and the process concept of upgrading paper-grade pulp into dissolving pulp are also included. Some recent developments related to the analytical methods of the purity and molecular weight distribution based on the ion chromatography and gel permeation chromatography are discussed. Finally, further processing improvements of purification, such as mechanical, chemical, and enzymatic treatment, and their combinations during the manufacturing process of dissolving pulp, are included. [ABSTRACT FROM AUTHOR]

Three measures, namely, the adaptive barrier update strategy, the filter-line-search method and the feasibility restore phase, are simultaneously introduced in the conventional primal-dual interior point method (IPM) framework to enhance the robustness of existing optimal power flow algorithms when applied to systems with considerable number of flexible AC transmission system (FACTS) devices. First, an adaptive barrier parameter strategy is employed to update the barrier parameter after the current μ-barrier problem solved to certain accuracy. Second, a filter-line-search procedure is introduced to generate the next iterate. Third, the algorithm initiates a feasibility restore phase as a remedy in case of getting stuck at a non-optimal point. Comparative case studies with previous algorithms on both standard test systems and large-scale real-world systems demonstrate the novel algorithm outperforms conventional IPMs in robustness and efficiency. [ABSTRACT FROM AUTHOR]

Charge transport properties in close-packed nanoparticle arrays with thickness crossing over from two dimensions to three dimensions have been studied. The dimensionality transition of nanoparticle arrays was realized by continually printing spatially well-defined nanoparticle monolayers on top of the device in situ. The evolution of charge transport properties depending on the dimensionality has been investigated in both the Efros-Shaklovskii variable-range-hopping (ES-VRH) (low temperature) regime and the sequential hopping (SH) (medium temperature) regime. We find that the energy barriers to transport decrease when the thickness of nanoparticle arrays increases from monolayer to multilayers, but start to level off at the thickness of 4-5 monolayers. The energy barriers are characterized by the coefficient βD at ES-VRH regime and the activation energy Ea at SH regime. Moreover, a turning point for the temperature coefficient of conductance was observed in multilayer nanoparticle arrays at high temperature, which is attributed to the increasing mobility with decreasing temperature of hopping transport in three dimensions. [ABSTRACT FROM AUTHOR]

Pathogenic mechanisms underlying the development of lung cancer are very complex and not yet entirely clarified. T lymphocytes and their immune-regulatory cytokines play a pivotal role in controlling tumor growth and metastasis. Following activation by unique cytokines, CD4+ T helper cells differentiate into Thl, Th2, Thl7, and regulatory T cells (Tregs). Traditionally, research in lung cancer immunity has focused almost exclusively on Thl/Th2 cell balance. Recently, Thl7 cells and Tregs represent an intriguing issue to be addressed in lung cancer pathogenesis. Tregs play an important role in the preservation of self-tolerance and modulation of overall immune responses against tumor cells. Thl7 cells directly or via other proinflammatory cytokines modulate antitumor immune responses. Notably, there is a close relation between Tregs and Thl7 cells. However, the possible interaction between these subsets in lung cancer remains to be elucidated. In this setting, targeting Treg/Thl7 balance for therapeutic purposes may represent a useful tool for lung cancer treatment in the future. The purpose of this review is to discuss recent findings of the role of these novel populations in lung cancer immunity and to highlight the pleiotropic effects of these subsets on the development and regulation of lung cancer. [ABSTRACT FROM AUTHOR]

Late Mesozoic volcanic-subvolcanic rocks and related iron deposits, known as porphyry iron deposits in China, are widespread in the Ningwu ore district (Cretaceous basin) of the middle-lower Yangtze River polymetallic ore belt, East China. Two types of Late Mesozoic magmatic rocks are exposed: one is dioritic rocks closely related to iron mineralization as the hosted rock, and the other one is granodioritic (-granitic) rocks that cut the ore bodies. To understand the age of the iron mineralization and the ore-forming event, detailed zircon U-Pb dating and Hf isotope measurement were performed on granodioritic stocks in the Washan, Gaocun-Nanshan, Dongshan and Heshangqiao iron deposits in the basin. Four emplacement and crystallization (typically for zircons) ages of granodioritic rocks were measured as 126.1±0.5 Ma, 126.8±0.5 Ma, 127.3±0.5 Ma and 126.3±0.4 Ma, respectively in these four deposits, with the LA-MC-ICP-MS zircon U-Pb method. Based on the above results combined with previous dating, it is inferred that the iron deposits in the Ningwu Cretaceous basin occurred in a very short period of 131-127 Ma. In situ zircon Hf compositions of εHf( t) of the granodiorite are mainly from -3 to -8 and their corresponding 176Hf/177Hf ratio are from 0.28245 to 0.28265, indicating similar characteristics of dioritic rocks in the basin. We infer that granodioritic rocks occurring in the Ningwu ore district have an original relationship with dioritic rocks. These new results provide significant evidence for further study of this ore district so as to understand the ore-forming event in the study area. [ABSTRACT FROM AUTHOR]

Emphysema is a T-cellmediated autoimmune disease caused predominantly by cigarette smoking. Th17 cells and related cytokines may contribute to this disorder.However, the possible implication of Th17 cells in regulating inflammatory response in emphysema remains to be elucidated. In the current study, we tested the protein levels of IL-17 and IL-21 in peripheral blood and lung tissues from cigarette-smoke- (CS-) exposedmice and air-exposedmice, analyzed the frequencies of CD4+IL-17+(Th17) cells, IL-21+Th17 cells, and CD8+IL-21R+ T cells in peripheral blood and lung tissues of mice, and their relationship with emphysematous lesions, and explored the impact of IL-21 on cytotoxic CD8+ T cells function in vitro. It was found that the frequencies of Th17, IL- 21+Th17, and CD8+IL-21R+ T cells and the levels of IL-17 and IL-21 of CS-exposed mice were much higher than those of the air-exposed mice and correlated with emphysematous lesions. Additionally, the number of IL-21+Th17 cells positively correlated with the number of CD8+IL-21R+ T cells. The in vitro experiments showed that IL-21 significantly augmented the secretion of perforin and granzyme B in CD8+ T cells from CS-exposed mice. These data indirectly provide evidence that Th17 cells could be involved in the control of the local and systeminflammatory response in emphysema by regulating CD8+ cytotoxic T-cell function. [ABSTRACT FROM AUTHOR]

A commercial age-hardenable Al-7136 alloy was successfully processed by high-pressure torsion (HPT) at room temperature through 1/8 to 4 turns. Microhardness measurements showed significant hardening even after 1/8 turn with the average hardness value reaching a maximum after 1 turn and then slowly decreasing. Higher hardness values were attained by processing the alloy through one pass of equal-channel angular pressing in a supersaturated condition at room temperature and then applying HPT for 1 or 2 turns. Microstructural observations revealed the possibility of achieving true nanometer grain sizes of <100 nm after processing at room temperature. There were variations in hardness with imposed strain due to the fragmentation and subsequent growth of precipitates during processing. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of chiral alkylphosphonates bearing a β-stereogenic center, based on the Rh-catalyzed asymmetric hydrogenation of corresponding β-substituted β,γ-unsaturated phosphonates with a ferrocenebased monophosphoramidite ligand under the mild hydrogenation conditions, was developed, in which an ee value of up to 98% was obtained. [ABSTRACT FROM AUTHOR]

The influences of an Fe cap layer on the structural and magnetic properties of FePt/Fe bi-layers are investigated. Compared with single FePt alloy films, a thin Fe layer can affect the crystalline orientation and improve the chemical ordering of L10 FePt films. Moreover, the coercivity increases when a thin Fe layer covers the FePt layer. Beyond a critical thickness, however, the Fe cover layer quickens the magnetization reversal of Fe49Pt51/Fe bi-layers by their exchange coupling. [ABSTRACT FROM AUTHOR]

A series of chiral -aryl--amino acid ester derivatives were synthesized in high enantioselectivities (93−97% ee) via the Rh-catalyzed asymmetric hydrogenation of -phthalimido-,-unsaturated carboxylic acid esters using highly modular chiral BoPhoz-type phosphine−aminophosphine ligands. The method has been applied successfully to the synthesis of several chiral pharmaceuticals including (R)-baclofen and (R)-rolipram with high enantioselectivities. [ABSTRACT FROM AUTHOR]

The construction of micro/nanohierarchical structures on cellulose-based materials to prepare membranes with special wettability has a promising application. Herein, a simple two-step preparation process, including immersion of the cotton fabric in the copper ammonia solution and drying, was used to grow copper hydroxide (Cu(OH)2) on/in the cotton fibers in a homogeneous reaction, avoiding severe agglomeration of Cu(OH)2 particles and endowing the fabric with superhydrophilicity and underwater superoleophobicity. Driven by gravity, the prepared Cu(OH)2@cotton fabric could be used to separate different oil-water mixtures and oil-in-water emulsions as well as having good mechanical and chemical stability. This simple, low-cost, mass-applicable method offers new perspectives for designing the membrane with special wettability based on cotton fabrics, with promising applications. [ABSTRACT FROM AUTHOR]

A series of chiral 3-aryl-4-phosphonobutyric acid esters were synthesized in high enantioselectivities (93-98% ee) via the Rh-catalyzed asymmetric hydrogenation of the corresponding 3-aryl-4-phosphonobutenoates using a P-stereogenic BoPhoz-type phosphine-aminophosphine ligand. The methodology has been successfully applied to the asymmetric synthesis of a potential GABAB antagonist, (R)-phaclofen, in high enantioselectivity. [ABSTRACT FROM AUTHOR]

Most known copper (Cu) skarns are associated with oxidized intrusions. In this contribution, we report a Cu skarn associated with a reduced monzodioritic intrusion at Huanren, northeastern China, which contains 0.41 Mt of Cu accompanied by economic concentrations of Zn, Pb, Fe, Mo, and Ag. Copper-polymetallic mineralization in the Huanren deposit is concentrated in skarns located between the contacts of the monzodiorite (SiO2 = 52–55 wt%) and the Cambrian carbonate rocks, with minor molybdenite-bearing veinlets/veins and dissimilated chalcopyrite mineralization hosted within the monzodiorite. Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) U-Pb zircon geochronology indicates the monzodiorite crystallized at 125.4 ± 0.6 Ma (2σ). Isotope dilution (ID)-ICP-MS Re-Os molybdenite geochronology indicates mineralization at Huanren occurred at 125.3 ± 0.8 Ma (2σ). Whole-rock major- and trace-element and zircon Hf isotopic compositions suggest enriched (subduction metasomatized) lithospheric mantle–derived sources for the parental magma of the monzodiorite without significant crustal assimilation. Zircon trace-element and magmatic apatite major-element compositions indicate the reduced nature of the monzodiorite, as evidenced by low magmatic oxygen fugacity (fayalite-magnetite-quartz [FMQ] buffer = −1.09 ± 0.19) and negligible apatite SO3 contents (<0.05 wt%). A reduced magmatic-hydrothermal system at Huanren is also supported by the predominance of magmatic ilmenite over magnetite in the monzodiorite and by the presence of pyrrhotite and the absence of anhydrite and hematite in the ore. Chalcopyrite from the Huanren deposit has an average δ34S value of 4.34‰ ± 0.88‰ (1σ), which is clearly higher than values from most porphyry-skarn Cu ± Mo ± Au deposits. Accordingly, we suggest that interaction between (1) external oxidized fluids equilibrated with evaporites and (2) reduced Cl-bearing magmas and related exsolved fluids may have played a critical role in the formation of the Huanren Cu skarn by increasing the ability of fluids to scavenge Cu from the reduced magma and subsequently precipitate Cu in the carbonate rocks. This study defines a new type of Cu skarn and thereby opens new potential for Cu skarn exploration proximal to intrusive units previously deemed too reduced to be Cu fertile, especially in non-arc settings. Moreover, we conclude that the availability of Cl and S in magmatic-hydrothermal systems may be as critical as fO2 in facilitating the actual oreforming event in Cu skarn systems. [ABSTRACT FROM AUTHOR]

Intrigued by the discovery of high-temperature superconductivity in a single unit-cell layer of FeSe film on SrTiO3, researchers recently found large superconductinglike energy gaps in K-adsorbed multilayer FeSe films by angle-resolved photoemission and scanning tunneling spectroscopy. However, the existence and nature of the high-temperature superconductivity inferred by the spectroscopic studies has not been investigated by measurements of zero resistance or the Meissner effect due to the fragility of K atoms in air. Using a self-developed multifunctional scanning tunneling microscope, we succeed in observing the diamagnetic response of K-adsorbed multilayer FeSe films, and thus find a dome-shaped relation between the critical temperature (Tc) and K coverage. Intriguingly, Tc exhibits an approximately linear dependence on the superfluid density in the whole K adsorbed region. Moreover, the quadratic low-temperature variation in the London penetration depth indicates a sign-reversal order parameter. These results provide compelling information towards further understanding of the high-temperature superconductivity in FeSe-derived superconductors. [ABSTRACT FROM AUTHOR]

The Luanling gold deposit is a lode gold deposit in the Xiong'ershan region located on the southern margin of the North China Craton. Based on typical mineral assemblages and relative Au contents, the pyrites in the Luanling deposit can be divided into four types: Py1‐s, pyrite with abnormally high levels of Au in pyrite–quartz veins; Py1, pyrite with low levels of Au in pyrite–quartz veins; Py2‐1, pyrite intergrowth with molybdenite; and Py2‐2, pyrite with higher concentrations of Au in association with molybdenite. Inductively coupled plasma mass spectrometry analyses reveal that the gold mainly occurs as "visible gold" (either native gold or electrum) inclusions and disseminations. "Invisible gold" is only hosted in the Py2‐2 pyrite grains, and Py1 and Py2‐1 contain low levels of Au concentrations (Py1 ≤ 6.563 ppm; Py2‐1 ≤ 8.377 ppm). Interestingly, As shows a strong correlation with gold concentrations in Py2‐2. The δ34S values of Py1 from Stage I span from −7.4‰ to −5.1‰. At Stage II, the δ34S values of Py2‐1 exhibit a range of −11.0‰ to −7.5‰. Pyrite in Py2‐2 shows δ34S values from −12.6‰ to −11.0‰. In situ sulfur isotope analyses of pyrite show an obvious decreasing trend, which is a result decreasing ore‐forming temperatures during the ore‐forming process. The He–Ar isotope data indicate that the ore‐forming fluids were derived from a mantle‐fluid mixing source. The metallogenesis in the Luanling deposit is closely related to the lithospheric thinning and the destruction of the North China Craton. [ABSTRACT FROM AUTHOR]

α decay is usually associated with both ground and low-lying isomeric states of heavy and superheavy nuclei, and the unpaired nucleon plays a key role in α decay. In this work, we systematically studied the α decay half-lives of odd-A nuclei, including both favored and unfavored α decay within the two-potential approach based on the isospin dependent nuclear potential. The α preformation probabilities are estimated by using an analytic formula taking into account the shell structure and proton-neutron correlation, and the parameters are obtained through the α decay half-lives data. The results indicate that, in general, the α preformation probabilities of even-Z, odd-N nuclei are slightly smaller than the odd-Z, even-N ones. We found that the odd-even staggering effect may play a more important role on spontaneous fission than α decay. The calculated half-lives can well reproduce the experimental data. [ABSTRACT FROM AUTHOR]

Lyocell fiber has emerged as an important class of regenerated cellulose that is produced based on the N-methyl morpholine-N-oxide (NMMO) dissolution method, and it has unique properties compared to viscose fiber. The NMMO technology provides a simple, resource-conserving, and environmentally friendly method for producing regenerated cellulose fiber. In this paper, the manufacturing process, environmental impact, and product quality of lyocell fiber are reviewed and compared with those of the conventional viscose fiber. [ABSTRACT FROM AUTHOR]

In recent years, the decontamination of heavy metals from bodies of water has become an important topic in China because of rapid industrialization, and it is of both fundamental and practical interest to develop ecofriendly, renewable, and degradable materials for this purpose. In this study, cellulose-based adsorbent materials were prepared, based on the carboxymethylation modification method. A carboxymethylated cellulose fiber (CMF) material with a high carboxyl content and desirable fiber morphology was obtained, and its application in the removal of heavy metal ions, such as copper ions, by a filtration-adsorption process, was investigated. The results showed that the CMF-based adsorbent material displayed an excellent adsorption capacity and regeneration properties because of its high carboxyl content and accessibility to copper ions. Moreover, the CMF material retained a good fiber morphology because of the mild carboxymethylation on the fiber surfaces (exterior and interior), which gives it great potential as a commercial renewable filtering material for copper-ion removal. [ABSTRACT FROM AUTHOR]

Ramie fabrics are suitable for summer clothing due to their excellent moist)ure absorption and breathability. Still, their application in the garment industry is limited by the presence of stiff, coarse hairiness that tends to prickle when it comes into contact with the skin. Herein, a low concentration copper ammonia solution was used to slenderize the fiber of the ramie fabric for a short time at room temperature to eliminate prickle and improve the softness of the fabric. Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermal gravity analysis (TG) were used to investigate the morphology and structure of treated ramie fabric. And its softness, smoothness, fiber diameter, breaking strength, air permeability, and moisture absorption were also studied. The results showed that the fibers were slenderized, the stiff, coarse hairiness was reduced, and the softness of the fabric was improved, while its other proper)ties remained good after the ramie fabric was treated under appropriate conditions. The use of copper ammonia solution at room temperature to eliminate the prickle of ramie fabrics was simple and inexpensive, suitable for use in practical production. [ABSTRACT FROM AUTHOR]

A new family of unsymmetrical ferrocenylethylamine-derived monophosphoramidites were synthesized and successfully applied in the Rh-catalyzed enantioselective hydrogenation of a range of enamides and α-dehydroamino acid esters, and ee values of up to 99.5% were obtained for both types of substrate. These results suggest that unsymmetrical amine-derived monophosphoramidites can also exhibit excellent enantioselectivity for a broad range of substrates, comparable to or higher than those of the most efficient symmetrical amine-derived monophosphoramidites reported thus far. [ABSTRACT FROM AUTHOR]

Microgrids may suffer from full blackouts when confronted with unexpected disruptions due to man-made faults or natural disasters. How to quickly restore the power supply of microgrids by making use of local distributed energy resources (DERs) is therefore a practical issue to help microgrids ride through full blackouts. Accordingly, this study proposes a novel black start strategy for microgrids to determine the restoration sequence and optimally allocate the DERs after full blackouts. In particular, the uncertainty of power output of renewable energy sources is considered using a data-driven chance-constrained approach when renewable energy sources are integrated. The proposed approach only utilises historical data and does not need any prior knowledge about the true probability distribution of the uncertainty. In addition, affine-based techniques and sample-dependent band functions are developed to convert the chance-constrained problem into a tractable mixed-integer linear programming problem. Finally, numerical experiments based on two microgrid test systems are performed to validate the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

We investigated morphology transitions of linear tetrablock copolymers of polystyrene-block-polyisoprene-block-polystyrene-block-polyisoprene (S1I1S2I2) by varying volume fraction of PI1 block (fPI1), while maintaining the symmetric volume fraction of total PS blocks and PI blocks (fPS1+fPS2:fPI1+fPI2 ≈ 1:1). An interesting sequence of morphology transitions was observed as fPI1 was increased: lamellae (L) → asymmetric lamellae (aL) → hexagonally packed PI-cylinders (CPI) → double gyroid with PI-network domains (GPI) → short-period lamellae (sL). The domain spacing of sL was nearly half that of L, while aL had asymmetric lamellar width of PS and PI microdomains. It is particularly interesting that cylindrical and gyroid morphologies were observed in linear block copolymers with symmetric overall volume fraction at intermediate segregation. The experimentally observed morphologies are in good agreement with the predicted equilibrium phases by self-consistent field theory (SCFT). [ABSTRACT FROM AUTHOR]

Langevin dynamics simulations have been performed to investigate the response of bi-disperse and strong polyacid chains grafted on an electrode to electric fields generated by opposite surface charges on the polyelectrolyte (PE)-grafted electrode and a second parallel electrode. Simulation results clearly show that, under a negative external electric field, the longer grafted PE chains are more strongly stretched than the shorter ones in terms of the relative change in their respective brush heights. Whereas under a positive external electric field, the grafted shorter chains collapse more significantly than the longer ones. It was found that, under a positive external electric field, the magnitude of the total electric force acting on one shorter PE chain is larger than that on one longer PE chain, or vice versa. The effects of smeared and discrete charge distributions of grafted PE chains on the response of PE brushes to external electric fields were also examined. [ABSTRACT FROM AUTHOR]

The Primary Test Stand (PTS) developed at the China Academy of Engineering Physics is a 20 TW pulsed power driver, which can deliver a ~10 MA, 70 ns rise-time (10%-90%) current to a short-circuit load and has important applications in Z-pinch driven inertial confinement fusion and high energy density physics. Preliminary results of tungsten wire-array Z-pinch experiments on PTS are presented. The load geometries investigated include 15-mm-tall cylindrical single and nested arrays with diameter ranging from 13mm to 30 mm, consisting of 132-300 tungsten wires with 5-10 μm in diameter. Multiple diagnostics were fielded to characterize the x-ray radiation from wire-array Z pinches. The x-ray peak power (~50 TW) and total radiated energy (~500 kJ) were obtained from a single 20-mm-diam array with 80-ns stagnation time. The highest x-ray peak power up to 80 TW with 2.4 ns FWHM was achieved by using a nested array with 20-mm outer diameter, and the total x-ray energy from the nested array is comparable to that of single array. Implosion velocity estimated from the time-resolved image measurement exceeds 30 cm/μs. The detailed experimental results and other findings are presented and discussed. [ABSTRACT FROM AUTHOR]

Background: To investigate the expression status of PIWIL2 and piR-932 in breast cancer stem cells and the role they could play in tumor cell growth and metastasis through Latexin. Methods: CD44+/CD24- tumor cells (CSC) from clinical specimens were sorted using flow cytometry. PIWIL2 expression status was detected in CSC cells by microarray analysis and 1086 breast cancer specimens byWestern blot and immunohistochemistry staining. piR-932 expressionwas also detected in CSC cells by piRNA microarray assay. The relationship between the PIWIL2 protein and clinicopathological parameters and prognosis was subsequently determined. Results: CSC cells are more likely to generate new tumors in mice and cell microspheres that are deficient in NOD/SCID compared to the control group. PIWIL2 protein was expressed higher in CSC cells compared to the control cells. In total, 334 (30.76%) of the 1086 breast cases showed high PIWIL2 expression. PIWIL2was observed to be related to age, tumor size, histological type, tumor stage, and lymph node metastasis (all P < 0.05). Furthermore, we have found that one of the Piwi-interacting RNAs (piRNAs) called piR-932 expressed significantly higher in the breast cancer cells that were induced to EMT, and it could form immune complexes through immunoprecipitation with PIWIL2; in PIWIL2+ breast cancer stem cells, Latexin expression significantly reduced because of its promoter region CpG island methylation. Conclusions: These results suggest that the combination of piR-932 and PIWIL2 may be a positive regulator in the process of breast cancer stem cells through promoting the methylation of Latexin, and they both could be the potential targets for blocking the metastasis of breast cancer. [ABSTRACT FROM AUTHOR]

Abstract: The Middle-Lower Yangtze (Changjiang) River Valley metallogenic belt is located on the northern margin of the Yangtze Craton of eastern China. Most polymetallic deposits in the Changjiang metallogenic belt are clustered in seven districts where magmatism of Mesozoic age (Yanshanian tectono-thermal event) is particularly extensive. From west to east these districts are: E-dong, Jiu-Rui, Anqing-Guichi, Lu-Zong, Tong-Ling, Ning-Wu and Ning-Zhen. World-class iron ore deposits occur in the Lu-Zong and Ning-Wu ore clusters, which are mainly located in continental fault-bound volcanic-sedimentary basins. One of these deposits is the Longqiao iron deposit, discovered in the northern part of the Lu-Zong Basin in 1985. This deposit consists of a single stratabound and stratiform orebody, hosted in sedimentary carbonate rocks of the Triassic Dongma''anshan Formation. A syenite pluton (Longqiao intrusion) is situated below the deposit. The iron ore is massive and disseminated and the ore minerals are mainly magnetite and minor pyrite. Wall rock alteration mostly consists of skarn minerals, such as diopside, garnet, potassic feldspar, quartz, chlorite, phlogopite and anhydrite. Thin sedimentary siderite beds of Triassic age occur as relict laminated ore at the top and the margin of the magnetite orebody. These sideritic laminae are part of Triassic evaporite-bearing carbonate deposits (Dongma''anshan Formation). Sulfur isotopic compositions show that the sulfur in the deposit was derived from a mixture of magmatic hydrothermal fluids and carbonate–evaporite host rocks. Similarly, the C and O isotopic compositions of limestones from the Dongma''anshan Formation indicate that these rocks interacted with magmatic hydrothermal fluids. The O isotopic compositions of the syenitic rocks and minerals from the deposit show that the hydrothermal magnetite and skarn minerals were formed from magmatic fluids. The Pb isotopic compositions of sulfides are similar to those of the Longqiao syenite. Phlogopite coexisting with magnetite in the magnetite ores yielded a plateau age of 130.5±1.1Ma (2σ), whereas the LA-ICP MS age of the syenite intrusion is 131.1±1.5Ma, which is slightly older than the age of phlogopite. The Longqiao syenite intrusion may have crystallized from a parental alkaline magma, generated by partial melting of lithospheric mantle, during extensional tectonics. The ore fluids were probably first derived from magma at depth, later emplaced in the sedimentary rocks of the Dongma''anshan Formation, where it interacted with siderite and evaporite-bearing carbonate strata, resulting in the formation of magnetite and skarn minerals. The Longqiao iron deposit is a skarn-type stratabound and stratiform mineral system, genetically and temporally related to the Longqiao syenite intrusion. The Longqiao syenite is part of the widespread Mesozoic intracontinental magmatism (Yanshanian event) in eastern China, which has been linked to lithospheric delamination and asthenospheric upwelling. [Copyright &y& Elsevier]

Abstract: The solute segregation at grain boundaries (GBs) of an ultrafine grained (UFG) Al–Zn–Mg–Cu alloy processed by equal-channel angular pressing (ECAP) at 200°C was characterised using three-dimensional atom probe. Mg and Cu segregate strongly to the grain boundaries. In contrast, Zn does not always show clear segregation and may even show depletion near the grain boundaries. Trace element Si selectively segregates at some GBs. An increase in the number of ECAP passes leads to a decrease in the grain size but an increase in solute segregation at the boundaries. The significant segregation of alloying elements at the boundaries of ultrafine-grained alloys implies that less solutes will be available in the matrix for precipitation with a decrease in the average grain size. [Copyright &y& Elsevier]

The properties of keV x-ray radiations from Mo and Ti X-pinch plasma sources at the current of 800 kA were investigated by a pinhole transmission grating spectrometer. The spectrometer was characterized by a high linear dispersion rate (2.9 Å/mm), and from its time-integrated diffraction images, rich information about the X-pinch sources (e.g., source number, source size, and absolute spectra) could be obtained. Multiple hot spots were produced in all the Mo tests with loads made of two or four 25 μm wires with or without a shunt wire, and obvious increases both in the radiation intensity and in the source size around the spectral region of 2.6 keV were observed. In Ti X-pinch tests, a single keV x-ray burst with a source size of ∼200 μm and a time duration of ∼200 ps in full width at half maximum was obtained using a load made of two 50 μm wires plus a shunt wire. The intensity of x-rays decreased sharply from ∼1011 photon eV-1 sr-1 at 1 keV to ∼108 photon eV-1 sr-1 at 4 keV. The energy-dependent source size in the band of 1–4 keV is less than 100 μm and seemed to shrink quickly as x-ray energy increases. [ABSTRACT FROM AUTHOR]

A new class of chiral ferrocenyl diphosphine ligands with an imidazole ring, (Rc,SFc)-ImiFerroPhos, has been prepared from acylferrocenes through a five-step transformation and successfully applied in the Rh-catalyzed asymmetric hydrogenation of various 3-aryl-substituted 2-phosphonomethylpropenoates, in which a series of chiral 3-phosphono-2-arylmethylpropanoic acid derivatives were achieved in ee values of up to 98%. [ABSTRACT FROM AUTHOR]

A new class of unsymmetrical hybrid phosphine-aminophosphine ligands has been prepared from commercially available, inexpensive (S)-1-phenylethylamine through a concise synthetic procedure. These ligands are not very sensitive to air and moisture, and displayed good enantioselectivities in the Rh-catalyzed asymmetric hydrogenation of various dimethyl α-benzoyloxyethenephosphonates bearing β-aryl, β-alkyl, and β-alkoxy substituents and N-benzyloxycarbonyl α-enamido phosphonates, in which up to 97% ee was obtained. A side-by-side comparison study disclosed that these new phosphine-aminophosphine ligands showed better enantioselectivity than BoPhoz ligands. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of optically active 1-aryl or 1-alkyl substituted ethyiphosphonates, based on the first Rh- catalyzed asymmetric hydrogenation of corresponding α,β-unsaturated precursors with a P-stereogenic BoPhoz-type ligand under the mild condition, was developed, in which a wide range of 1-aryl or 1-alkyl substituted ethyiphosphonates were achieved in up to 98% ee. [ABSTRACT FROM AUTHOR]

A series of chiral β-aryl-substituted γ-amino butyric acid derivatives were synthesized in good enantioselectivities via the Cu-catalyzed asymmetric conjugate reduction of γ-phthalimido-α,β-unsaturated carboxylic acid esters using Cu(OAc)2·H2O as a catalyst precursor, (S)-BINAP as a ligand, PMHS as a hydride source, and t-BuOH as an additive. The methodology has been applied successfully to the enantioselective synthesis of a chiral pharmaceutical, (R)-baclofen. [ABSTRACT FROM AUTHOR]

A series of BoPhoz-type ligands were successfully applied in the rhodium-catalyzed asymmetric hydrogenation of a number of β-substituted or unsubstituted α-(phthalimidomethyl)acrylates, affording good to excellent enantioselectivities. The results suggested that the presence of an N-H proton in the BoPhoz backbone could significantly improve the enantioselectivity, and ligand (Sc,Rp)-1d, bearing two CF3-groups in the 3,5-position of the phenyl ring of aminophosphino moiety, showed the highest enantioselectivity. [ABSTRACT FROM AUTHOR]