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The SMEN protocol, proposed by Wu and Ustaoglu in 2009, has been considered to be secure as the authors claimed, and numerous theories are proposed based on this protocol. This paper analyzes the SMEN protocol and finds that this protocol is not resistant to the session corruption attack and the key compromise impersonation attack. Then, we propose an improved protocol with tight security reduction. Our improved protocol not only avoids the above attacks but also embraces the same efficiency as the SMEN protocol in terms of exponentiation. Besides, formal analysis of the improved protocol is presented by using the formal automatic security analysis tool Scyther. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Despite extensive efforts to understand the tectonic evolution of the Jiangnan Orogen in South China, the orogenic process and its mechanism remain a matter of dispute. Previous geodynamic studies have mostly focused on collisional orogeny, which is commonly invoked to explain the Jiangnan Orogen. However, it is difficult for such hypotheses to reconcile all the geological and geophysical data, especially the absence of ultrahigh‐pressure metamorphic rocks. Based on the magnetotelluric data, we present a group of resistivity models produced through the combination of two ‐dimensional and three‐dimensional inversions, revealing the geo‐electrical structures of Jiangnan and a typical collisional orogen. In our models, the resistive crust is separated into three parts by a prominent conductive layer with opposite dipping directions on both sides. A special thrust‐nappe system, which is different from that developed in a typical collisional process, is revealed in the Jiangnan Orogen. This structure suggests a process different from the simple collisional orogeny. To interpret our observations, an 'intra‐continental orogeny' is proposed to address the development of the Jiangnan Orogen in the Mesozoic. Furthermore, this 'reworked' process may contain at least two stages caused by the decoupling of the lithosphere, which is revealed by an extra conductive layer beneath Jiangnan. [ABSTRACT FROM AUTHOR]

A great amount of new S‐wave data has been combined to image the mantle structure down to lower mantle depth near the southeastern margin of Eurasia and understand the tectonics in South China since the Mesozoic. Our results reveal a large‐scale structure beneath the South China Sea, with a prominent, broad low‐velocity feature of at least 1500‐km wide in and below the mantle transition zone (MTZ) and a pronounced low‐velocity feature of nearly 500‐km wide in the lowermost mantle. Together these features may represent the head‐and‐tail of an upwelling mantle plume that has interacted with and deformed by the subducting plates in the region. The Andaman–Sumatra plate is seen subducting steeply without stagnation in the MTZ over the large‐scale low‐velocity structure, suggesting that the upwelling mantle may have exerted significant influence on the overlying plate tectonics. Our results suggest a long‐term extensional regime near the southeastern margin of Eurasia, which may help to understand the formation of the large‐scale intra‐plate magmatism and mineralization with accumulation of huge amount of rare metal elements in South China during the Mesozoic, and the continental breakup, the southeastward extrusion of Indochina, and the opening of the South China Sea during the Cenozoic. [ABSTRACT FROM AUTHOR]

An effective approach for monodesulfonation of polyphenol sulfonate under ultrasonic irradiation was reported. Series of substituted ortho‐, meta‐ or para‐hydroxylphenol sulfonates or 5‐hydroxy‐1,3‐phenylene bis(4‐methylbenzenesulfonate) were obtained specifically in the presence of sodium hydroxide in acetonitrile. With treatment of potassium carbonate in alcohol, alkyloxylphenol sulfonates was provided via one‐pot monodesulfanation followed by alkylation under ultrasonicated solvent‐free conditions. The alcohol had been regarded as green alkylation reagent. The results of the exploration of the scalability of monodesulfonation and one‐pot monodesulfonation‐alkylation of resorcinol bissulfonate indicated that such modes had the potential application value in scale production. [ABSTRACT FROM AUTHOR]

In order to illuminate the hindering effects induced by grain boundaries on the propagation behavior of crack with respect to 15‐5 PH stainless steel, interactions between propagated crack and typical grain boundaries, including the parent austenite grain boundary (PAGB), coincidence site lattice Σ3 grain boundary (CSL Σ3), packet grain boundary (PGB), and block grain boundary (BGB) are investigated at the atomic scale. Results indicate that the higher stress in the crack initiation (CI) stage and crack and grain boundary interaction (CGB) stage is required to drive the propagating crack in terms of the PAGB model compared to the other models, and the longest interaction time between propagated crack and established grain boundary is needed for the crack from the crack propagation (CP) stage to the CGB stage in the case of the PGB model. The PAGB and PGB are determined to be the most effective in hindering crack propagation in 15‐5 PH stainless steel. [ABSTRACT FROM AUTHOR]

Objective: Parkinson's disease (PD), also known as paralysis tremor, is a chronic disease of the central nervous system. It has been reported that hepatocyte nuclear factor 4 alpha (HNF4A) is upregulated in PD, but its specific function has not been well explored. Methods: We established an in vitro PD model in SH‐SY5Y cells stimulated with 1‐methyl‐4‐phenylpyridinium (MPP+). Meanwhile, the effect of HNF4A on MPP+‐treated SH‐SY5Y cell behavior was monitored by functional assays. Mechanism assays were conducted to verify the relationship among LINC00667/miR‐34c‐5p/HNF4A. Rescue experiments validated the regulatory mechanism in PD model. Results: The results revealed that depletion of HNF4A suppressed cell cytotoxicity and apoptosis caused by MPP+. Knockdown of HNF4A recovered MPP+‐stimulated oxidative stress and neuroinflammation. Mechanically, HNF4A was targeted and inhibited by miR‐34c‐5p. Furthermore, we found that LINC00667 positively modulated HNF4A expression via sequestering miR‐34c‐5p in MPP+‐stimulated SH‐SY5Y cells. Interestingly, the data indicated that HNF4A could transcriptionally activate LINC00667 expression. Rescue experiments presented that miR‐34c‐5p interference or HNF4A overexpression could mitigate the effects of LINC00667 knockdown on cell viability, cytotoxicity, cell apoptosis, oxidative stress, and neuroinflammation in MPP+‐treated SH‐SY5Y cells. Conclusion: Our study first proved LINC00667, miR‐34c‐5p, and HNF4A constructed a positive feedback loop in MPP+‐treated SH‐SY5Y cells, enriching our understanding of PD. [ABSTRACT FROM AUTHOR]

Recent evidence from laboratory experiments suggests that important disparities exist between willingness to pay (WTP) and compensation demanded for the same good. Because a fundamental postulate in neoclassical theory is that with small income effects and many available substitutes, the willingness to accept (WTA) and WTP measures of value for a commodity should be roughly equivalent, this finding has vast implications in both a positive and normative sense. This study advances, and experimentally tests, a new explanation of the WTP/WTA disparity-a dynamic theory based on the presence of commitment costs. Although to date neoclassical models have not explained the observed data patterns well, we find that the commitment cost theory combined with a simple behavioral anomaly is able to lend insights into the causes and severity of the WTA/WTP disparity. Furthermore, we find that market experience attenuates the behavioral anomaly, consistent with the notion that no value disparity exists for agents with sufficient market experience. [ABSTRACT FROM AUTHOR]

Due to payoff uncertainties combined with risk aversion and/or real options, farmers may demand a premium in order to adopt conservation tillage practices, over and above the compensation for the expected profit losses (if any). We propose a method of directly estimating the financial incentives required for adopting conservation tillage and distinguishing between the expected payoff and premium of adoption based on the observed behavior. We find that the premium may play a significant role in farmers' adoption decisions. In an application to the state of Iowa, we find that if a uniform conservation tillage adoption subsidy program were offered in 1992, over 86% of the subsidy program payments would be an income transfer to existing and low-cost adopters. En raison des incertitudes quant aux gains, combinées à l'aversion pour le risque et/ou aux options réelles, les agriculteurs pourraient réclamer une prime pour l'adoption de méthodes culturales de conservation du sol, une prime qui serait supérieure à l'indemnisation offerte en cas de perte de gains prévue (s'il y a lieu). Nous avons proposé une méthode fondée sur le comportement observé qui permet une estimation directe des incitatifs financiers exigés pour adopter les méthodes culturales de conservation du sol et qui fait une distinction entre les gains prévus et la prime d'adoption. Nous avons constaté qu'une prime pourrait influencer considérablement les décisions des agriculteurs quant à l'adoption de méthodes culturales de conservation du sol. En Iowa par exemple, nous avons trouvé que, si un programme de subventions uniforme pour l'adoption de méthodes de conservation du sol avait été offert en 1992, plus de 86 p. 100 des paiements du programme de subvention aurait constitué un transfert de revenus aux adopteurs existants et à faibles coûts. [ABSTRACT FROM AUTHOR]

Previous reports suggest that an important characteristic of chemosensitive neurones is an unusually large change of steady-state intracellular pH in response to a change in extracellular pH (ΔpHi/ΔpHo). To determine whether such a correlation exists between neurones from the medullary raphe (a chemosensitive brain region) and hippocampus (a non-chemosensitive region), we used BCECF to monitor pHi in cultured neurones subjected to extracellular acid--base disturbances. In medullary raphe neurones, respiratory acidosis (5% → 9% CO2) caused a rapid fall in pHi (ΔpHi ∼0.2) with no recovery and a large ΔpHi/ΔpHo of 0.71. Hippocampal neurones had a similar response, but with a slightly lower ΔpHi/ΔpHo (0.59). We further investigated a possible link between pHi regulation and chemosensitivity by following the pHi measurements on medullary raphe neurones with an immunocytochemistry for tryptophan hydroxylase (a marker of serotonergicu neurones). We found that the ΔpHi/ΔpHo of 0.69 for serotonergic neurones (which are stimulated by acidosis) was not different from either the ΔpHi/ΔpHo of 0.75 for non-serotonergic neurones (most of which are not chemosensitive), or from the ΔpHi/ΔpHo of hippocampal neurones. For both respiratory alkalosis (5% → 3% CO2) and metabolic alkalosis (22 mM → 35 mM HCO3-), ΔpHi/ΔpHo was 0.42-0.53 for all groups of neurones studied. The only notable difference between medullary raphe and hippocampal neurones was in response to metabolic acidosis (22 mM → 14 mM HCO3-), which caused a large pHi decrease in ∼80% of medullary... [ABSTRACT FROM AUTHOR]

Although carbon fibers (CFs) are born with special physicochemical properties, the common CFs show the poor adsorption performance owing to the lack of adsorption sites and porosity with low specific surface area. As emerging functional materials, metal‐organic frameworks (MOFs) have attracted significant attention due to excellent properties, which has the ability of remedying drawbacks of other materials. In this study, zeolitic imidazolate framework‐8 (ZIF‐8) was rapidly coated on the surface of carbon fibers (CFs) (CF/ZIF‐8) via in‐situ self‐assembly approach in 10 min. The scanning electron microscope (SEM) images show ZIF‐8 film on CF is dense and homogeneous due to the low reactivity of zinc acetate and the coordination interaction between Zn2+ and carboxyl of CF treated by nitric acid (CF‐COOH). The Brunauer‐Emmett‐Teller (BET) surface area of CF/ZIF‐8 composite is about 30 times larger than that of pristine CF. The adsorption selectivity of CFs was increased after the modification of ZIF‐8 demonstrating by adsorbing different dyes. The CF/ZIF‐8 composites were applied to remove congo red (CR) from aqueous solutions with the adsorption capacity 40 times more than that of pristine CF and CF‐COOH, because of the increasing specific surface, electrostatic interaction and π‐π interaction between ZIF‐8 and CR molecule. The MOFs/CFs composites we fabricated also have great promise applications in micro‐preconcentration and electrochemistry. [ABSTRACT FROM AUTHOR]

3‐(Trimethoxysilyl)‐1‐propanamine (APTMS) modified glass fiber membrane (APTMS‐GF) was prepared via chemical bonding with different volume ratios (APTMS : methanol=1:20, 1:10, 1:5), which was called APTMS‐GF‐1, −2 and −3, respectively. For congo red (CR) with the concentrations ranging from 5 to 45 mg L−1, the removal efficiencies were up to above 95% by filtration with APTMS‐GF composite membranes, but there was no distinct difference in removal capacity with increasing the volume ratio of APTMS. More importantly, on account of the electrostatic interaction, APTMS‐GF composite membrane could selectively separate and recycle neutral bromophenol blue (BPB), cationic methylene blue (MB) and anionic methyl orange (MO) from binary systems including BPB/CR, MB/CR, and MO/CR, respectively. Under the static adsorption, the adsorption process of CR on the APTMS‐GF composite membrane was better fitting with the pseudo‐second‐order kinetic model (R2=0.992) due to the electrostatic interaction, which was confirmed by the effects of inorganic ions and pH in solution. The structural advantage of glass fiber membrane with micropores made all of filtration fulfilled under atmospheric pressure in comparison to the reported membranes. As a result, this work provides a feasible method for fabricating the economic membrane in removing dyes. The 3‐(trimethoxysilyl)‐1‐propanamine modified glass fiber membrane was prepared for the selective separation and recycling of BPB (neutral), MB (cationic) and MO (anionic) from BPB/CR, MB/CR and MO/CR binary system by filtration, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Fucosylated chondroitin sulfate (FuCS) is a structurally distinct glycosaminoglycan, and its oligosaccharides exhibit excellent anticoagulant activity with lower risks of adverse effects and bleeding. Herein we report a facile approach to the synthesis of FuCS hexa‐ and nonasaccharides on the basis of the enzymatic degradation of chondroitin over 12 linear steps. As compared with a clinical low‐molecular‐weight heparin drug (enoxaparin), the nonasaccharide synthesized in this study displayed similar APTT activity and selective intrinsic factor Xase complex inhibitory activity ((12.9±0.83) n m) by binding to factor IXa with high affinity, thus offering promise for the development of new anticoagulant agents targeting the intrinsic coagulation pathway. [ABSTRACT FROM AUTHOR]

Fucosylated chondroitin sulfate (FuCS) is a structurally distinct glycosaminoglycan, and its oligosaccharides exhibit excellent anticoagulant activity with lower risks of adverse effects and bleeding. Herein we report a facile approach to the synthesis of FuCS hexa‐ and nonasaccharides on the basis of the enzymatic degradation of chondroitin over 12 linear steps. As compared with a clinical low‐molecular‐weight heparin drug (enoxaparin), the nonasaccharide synthesized in this study displayed similar APTT activity and selective intrinsic factor Xase complex inhibitory activity ((12.9±0.83) nm) by binding to factor IXa with high affinity, thus offering promise for the development of new anticoagulant agents targeting the intrinsic coagulation pathway. [ABSTRACT FROM AUTHOR]

Abstract: Fucosylated chondroitin sulfate (FuCS) is a structurally distinct glycosaminoglycan with excellent anticoagulant activity. Studies show that FuCS and its depolymerized fragments exhibit a different anticoagulant mechanism from that of heparin derivatives, with decreased risks of adverse effects and bleeding. However, further exploitation has been hindered by the scarcity of structurally defined oligosaccharides. Herein, facile method is reported for the synthesis of the repeating trisaccharide unit of FuCS based on the degradation of chondroitin sulfate polymers. A series of simplified FuCS glycomimetics that have highly tunable structures, controllable branches, and defined sulfation motifs were generated by copper‐catalyzed alkyne–azide cycloaddition. Remarkable improvement in activated partial thromboplastin time (APTT) assay activities was observed as the branches increased, but no significant influences were observed for prothrombin time (PT) and thrombin time (TT) assay activities. Further FXase inhibition tests suggested that glycoclusters 33 b–40 b selectively inhibited intrinsic anticoagulant activities, but had little effect on the extrinsic and common coagulation pathways. Notably, glycoclusters with the 2,4‐di‐O‐sulfated fucosyl residue displayed the most potency, which was in consistent with that of natural polysaccharides. These FuCS clusters demonstrated potency to mimic linear glycosaminoglycans and offer a new framework for the development of novel anticoagulant agents. [ABSTRACT FROM AUTHOR]