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Composite nanofibers derived from synthetic and natural polymers normally show desirable characteristics in biomedical applications. In this study, composite nanofibrous mats (denoted as CNMs) with diameters of around 300 nm were fabricated facilely using blends of chitosan, gelatin and shape memory polyurethane (SMPU) by electrospinning and subsequent post-treatment with a silver nitrate solution. The obtained CNMs have shape memory effect and show desirable water vapor transmission ratio, surface wettability, satisfactory biological properties including antibacterial activity against the common Gram-negative and Gram-positive bacteria, cytocompatibility demonstrated to fibroblast, and the hemostatic property through a whole-blood clotting test. In addition, such CNMs can possibly benefit the wound healing through shape fixation-assisted easy processing and shape recovery-assisted closure of cracked wounds, which can be fine-tuned by pre-programming. Therefore, the CNMs presented in this study can be used as potential smart wound dressings. [ABSTRACT FROM AUTHOR]

Surface modified with so-called protein-repellent or antifouling polymers has become indispensable for the development of modern therapeutic and diagnostic medical devices. In this work, a series of novel well-defined poly(2-methyl-2-oxazoline)- block-poly(4-vinyl pyridine) (PMOXA- b-P4VP) diblock copolymers were synthesized by using copper-catalyzed azide-alkyne cycloaddition reaction of α-alkynyl-PMOXA and ω-N-P4VP, in which α-alkynyl-PMOXA and ω-N-P4VP were prepared by cationic ring opening polymerization and atom transfer radical polymerization, respectively. Stable coatings were formed when dropping PAA solution on the top of PMOXA- b-P4VP pre-coatings, due to hydrogen-bonding interaction between P4VP and poly(acrylic acid) (PAA). The long-term stability of these PMOXA- b-P4VP/PAA coatings showed that increasing PMOXA chain length can improve not only the hydrophilicity but also the stability of the coatings. This simple method can form stable coatings on either inorganic (such as, silicon wafer and coverslip) or organic material [such as, poly(methyl methacrylate) sheet] surface. At the same time, for the high-hydratability of PMOXA chains, these crosslinked coatings showed well protein-resistant and platelet/cell-repellent properties, and the antifouling properties and long-term availability were enhanced increasing PMOXA polymerization degree. [ABSTRACT FROM AUTHOR]

Graphene/mono-(6-amino-6-deoxy)- β-cyclodextrin multilayer films composed of graphene sheet (GS) and mono-(6-amino-6-deoxy)- β-cyclodextrin (NH2- β-CD) were fabricated easily by two steps. First, negatively charged graphene oxide (GO) and positively charged mono-(6-amino-6-deoxy)- β-cyclodextrin (NH2- β-CD) were layer-by-layer (LBL) self-assembled on glassy carbon electrode (GCE) modified with a layer of poly(diallyldimethylammonium chloride) (PDDA). Then graphene/mono-(6-amino-6-deoxy)- β-cyclodextrin (GS/NH2- β-CD) multilayer films were built up by electrochemical reduction of graphene oxide/mono-(6-amino-6-deoxy)- β-cyclodextrin (GO/NH2- β-CD). Combining the high surface area of GS and the active recognition sites on β-cyclodextrin ( β-CD), the GS/NH2- β-CD multilayer films show excellent electrochemical sensing performance for the detection of DA with an extraordinary broad linear range from 2.53 to 980.05 µmol·L−1. This study offers a simple route to the controllable formation of graphene-based electrochemical sensor for the detection of DA. [ABSTRACT FROM AUTHOR]

To detect the quality of medicinal human albumin by capillary electrophoresis, we produced a fused-silica capillary coated with thermally cross-linked poly(vinyl pyrrolidone) to prohibit protein adsorption. This type of capillary was easily obtained by injecting an aqueous poly(vinyl pyrrolidone) solution into a fused-silica capillary and thermally annealing it at 200°C. Notably, stable and low electro-osmotic flow was obtained in the poly(vinyl pyrrolidone)-coated capillary at pH 2.20-9.00, and the separation of a mixture of four basic proteins indicated that the poly(vinyl pyrrolidone)-coated capillary exhibits excellent repeatability and separation efficiency; moreover, the separation of these four basic proteins could even be achieved at pH 7.00. The protein recovery percentage of human serum albumin in a single-protein solution and a mixed blood proteins solution was determined to be 97.03 and 95.40% in the poly(vinyl pyrrolidone)50-3 (representing the concentration of the capillary-injected poly(vinyl pyrrolidone) aqueous solution, 50 mg/mL, and thermal annealing time, 3 h) capillary, respectively. Based on these results, we used the poly(vinyl pyrrolidone)50-3-coated capillary to quantify the protein content of human albumin, and the results obtained from run to run, day to day and capillary to capillary demonstrated that the coated capillary could be used for quality testing commercially available human albumin. [ABSTRACT FROM AUTHOR]

Abstract: A helical TiO2 nanotube (TNT) array modified with cuprous oxide (Cu2O) electrode was fabricated and used for nonenzymatic glucose detection. The structure and morphology of Cu2O/TNT were characterized by X-ray diffraction and transmission electron microscopy. The electrocatalytic performance of Cu2O/TNT electrode for glucose oxidation was investigated by cyclic voltammetry and chronoamperometry. At an applied potential of +0.65V versus SCE, a linear range was obtained within the concentration range of 3.0–9.0mM with a detection limit of 62μM (signal/noise=3). The response time was approximately 3s after adding 0.10mM glucose. Formate and gluconic acid were identified as the main products of the glucose oxidation using 1H NMR spectrometry. A possible mechanism for continuous glucose oxidation was also proposed. [Copyright &y& Elsevier]

Optimization of waveguides based on surface plasmons in double-layer graphene (DLG) is presented. In contrast to previous treatments, the effects of both extrinsic scattering and intrinsic Landau damping are simultaneously considered in this analysis. We show that an optimum frequency and an optimum spacing between two graphene sheets can be found to minimize the attenuation of the plasmon propagation. The optical mode is found to be less lossy than the acoustic mode below a certain frequency, but above this frequency the situation is reversed. All observable features of DLG are corroborated by analytical or numerical results, shedding light on the possibility of compact and tunable DLG-based plasmonic waveguides. [ABSTRACT FROM AUTHOR]

this Letter, a graphene-based terahertz plasmonic waveguide is proposed. The proposed structure benefits from the enhanced confinement and increased attenuation length of graphene surface plasmon by placing the graphene sheet in proximity of metal layers. For a graphene-based slab waveguide, our data show a 20% increase in the plasmonic attenuation length and a 97% increase in the attenuation length normalized to the plasmonic wavelength, thus significantly increasing the propagation distance of the surface plasmon. Further, improvement is possible by optimizing dielectric mismatch, graphene-metal distance, waveguide width, and the Fermi energy of graphene. [ABSTRACT FROM AUTHOR]

An essay is presented regarding strobe lighting and the cathode ray tube (CRT) devices which were used by artist Andy Warhol for his exhibition "Shadows," featuring abstract and paintings. Topics include the consequences of using the devices, the multimedia event Exploding Plastic Inevitable (EPI) by Warhol which arranges film, music, and strobe to create an intermedia environment, and the concept of scholar Friedrich Kittler of tripartite and media typology.

Reduced graphene oxide (RGO) is used as a carbocatalyst for the electrochemical polymerization and in situ polymerization of 1-naphthylamine (1-NPA). Compared with graphene oxide (GO), RGO shows a much higher heterogeneous catalytic activity, not only on a solid electrode surface, but also in the liquid phase. The catalytic procedure is monitored by cyclic voltammetry (CV) and UV/Vis absorption spectroscopy. [ABSTRACT FROM AUTHOR]

An efficient one-pot reaction for the synthesis of oxoaporphine alkaloids has been developed. Twenty-three compounds of oxoaporphine alkaloids were prepared and assessed for their antitumor activities. Most compounds inhibited the growth of T-24 tumor cells in vitro. Particularly, 4B displayed the most potent activity with an IC 50 value of 0.5 μM, which was 19-fold more potent than the parent compound 4. The substitution at C3-position of oxoaporphine core by −NO 2 significantly enhanced the anticancer activity. Mechanism studies indicated that 4 and 4B induced cell cycle arrest at G2/M phase; in contrast, 4V induced cell cycle arrest at the S phase. Increase of mitochondrial ROS/Ca2+ and decrease of MMP, accompanied by activation of caspase-3/9, were observed in T-24 cells after exposure to compounds 4 , 4B and 4V , suggesting that the mitochondrial pathway was involved in the induced apoptosis. Moreover, compound 4B effectively inhibited tumor growth in a mouse xenograft model bearing T-24. [Display omitted] • One-pot reaction for synthesis of oxoaporphine alkaloids was developed. • A series of oxoaporphine alkaloids were synthesized. • 4B induced DNA damage, and caused significant G2/M cell cycle arrest. • 4B induced caspase-3/9-dependent apoptosis through mitochondrial dysfunction. • 4B effectively inhibited tumor growth in a mouse xenograft model bearing T-24. [ABSTRACT FROM AUTHOR]

Recent findings that human serum contains stably expressed microRNAs (miRNAs) have revealed a great potential of serum miRNA signature as disease fingerprints to diagnosis. Here we used genome-wide serum miRNA expression analysis to investigate the value of serum miRNAs as biomarkers for the diagnosis of Alzheimer's disease (AD). Illumina HiSeq 2000 sequencing followed by individual quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) assays was used to test the difference in levels of serum miRNAs between 50 AD patients and 50 controls in the screening stages. The detected serum miRNAs then were validated by qRT-PCR in 158 patients and 155 controls. MiR-98-5p, miR-885-5p, miR-483-3p, miR-342-3p, miR-191-5p, and miR-let-7d-5p displayed significantly different expression levels in AD patients compared with controls. Among the 6 miRNAs, miR-342-3p has the best sensitivity (81.5%) and specificity (70.1%) and was correlated to Mini-Mental State Examination score. This study identified six serum miRNAs that distinguish AD patients from healthy controls with high sensitivity and specificity. Serum miRNA panel (or miR-342-3p alone) may serve as a novel, noninvasive biomarker for AD. [ABSTRACT FROM AUTHOR]

In this paper, a novel copolymer consisting of sulfobetaine methacrylate (SBMA) and 2-aminoethyl methacrylate (AEMA) named as poly(SBMA-co-AEMA) was synthesized by conventional free-radical polymerization, the poly(SBMA-co-AEMA) zwitterionic copolymer was immobilized onto glass slides surface through polydopamine (PDA)-anchored coating and formed poly(SBMA-co-AEMA)-g-PDA coating. The defined copolymer was characterized by nuclear magnetic resonance hydrogen spectroscopy ( ¹H NMR) and gel permeation chromatography. The surface morphology, thickness, and chemical component of poly(SBMA-co-AEMA)-g-PDA coating were studied by atom force microscope, ellipsometry, and X-ray photoeleetron spectroscopy, respectively. The hydrophilicity and stability of these coatings were investigated by static water contact angles. And finally, the poly(SBMA-co-AEMA)- g-PDA coating was successfully applied into capillary inner surface for suppression electro-osmotic flow and protein separation by capillary electrophoresis. [ABSTRACT FROM AUTHOR]

Abstract: Background: MicroRNAs (miRNAs) are endogenous small RNAs of 21–25 nucleotides that post-transcriptionally regulate gene expressions. Recently, circulating miRNAs have been reported as promising biomarkers for neurodegenerative disorders and processes affecting the central nervous system. This study was conducted to investigate the potential role of serum miRNAs as diagnostic biomarkers for Alzheimer's disease (AD). Methods: Serum samples were obtained from 105 probable AD patients and 150 age- and gender-matched normal controls. The serum concentrations of miRNAs miR-9, miR-29a, miR-29b, miR-101, miR-125b, and miR-181c were measured with a real-time quantitative reverse transcriptase PCR (qRT-PCR) method. Results: We found both miR-125b and miR-181c were down-regulated while miR-9 was up-regulated in serum of AD patients compared with that of normal controls. Among the receiver operating characteristic (ROC) results, miR-125b alone showed its priority with a specificity up to 68.3% and a sensitivity of 80.8%. Importantly, miR-125b was correlated with the Mini Mental State Examination (MMSE) in AD patients. Conclusions: Our results indicate that serum miR-125b may serve as a useful noninvasive biomarker for AD. [Copyright &y& Elsevier]

This study describes the formation of highly efficient antiprotein adsorption random copolymer coating of poly(N,N-dimethylacrylarnide-co-sulfobetaine methacrylate) (poly(DMA-co-SBMA)) on the fused-silica capillary inner wall. Firstly, the poly (DMA-co-SBMA)s with different feed ratio (SBMA/DMA) were synthesized via the reversible addition fragmentation chain transfer polymerization. And then, X-ray photoelectron spectroscopy (XPS) and water contact angle (CA) were used to investigate the composition and hydrophilicity of poly(DMA-co-SBMA) coating formed on the glass slide surfaces. CA measurements revealed that the poly(DMA-co-SBMA) coating became more hydrophilic with the increment of feed ratio (SBMA/DMA), and at the same time, the XPS results showed that the coating ability was also increased with the increment of feed ratio. Followed, the copolymer was applied to coat the fused-silica capillary inner wall, and the coated capillary was used to separate the mixture of proteins (lysozyme, cytochrome c, ribonuclease A, and a-chymotrypsinogen A) in a pH range from 3.0 to 5.0. Under the optimum conditions, an excellent separation of basic proteins with peak efficiencies ranging from 551,000 to 1509,000 N/m had been accomplished within 10 min. Furthermore, the effect of coating composition on protein separation was also investigated through the comparison of separation efficiency achieved by using bare, PSBMA- and poly (DMA-co-SBMA)-coated capillary, respectively. [ABSTRACT FROM AUTHOR]

A series of double-hydrophilic double-grafted PMA- g-PEG/PDMA copolymers, which contained poly(methacrylate) (PMA) as backbone, poly(ethylene glycol) (PEG) and poly( N,N-dimethylacrylamide) (PDMA) as side chains synthesized successfully by using reversible addition-fragmentation chain transfer (RAFT) polymerization and atom transfer radical polymerization (ATRP), were used as physical coatings for the evaluation of protein-resistant properties by capillary electrophoresis (CE). Electroosmotic flow (EOF) measurement results showed that the PMA- g-PEG/PDMA copolymer coated capillaries could suppress electroosmotic mobility in a wide pH range (pH = 2.8–9.8) and EOF mobility decreased with the increase of copolymer molecular mass and PDMA content. At the same time, protein recovery, theoretical plate number of separation and repeatability of migration time demonstrated that antifouling efficiency was improved with the increase of molecular mass and PEG content. [ABSTRACT FROM AUTHOR]

Abstract: The kynurenine pathway (KP), the primary route of tryptophan degradation in mammalian cells, consists of many metabolites including kynurenic acid (KYNA), quinolinic acid (QUIN), 3-hydroxykynurenine (3-HK) and picolinic acid (PIC). The former two are neuroactive, while the latter two are molecules with pro-oxidants and antioxidants properties. These agents are considered to be involved in aging and numerous neurodegenerative diseases, such as Alzheimer''s disease (AD), Parkinson''s disease (PD), Huntington''s disease (HD) and amyotrophic lateral sclerosis (ALS). Several studies have demonstrated that altered kynurenine metabolism plays an important role in the pathogenesis of this group of diseases. The important metabolites and key enzymes show significant importance in those disorders. Both analogs of the neuroprotective metabolites and small molecule enzyme inhibitors preventing the formation of neurotoxic compounds may have potential therapeutic significance. In this review we discuss the mechanistic and therapeutic considerations of KP in aging and the main neurodegenerative diseases and review the updated knowledge in this therapeutic field. [Copyright &y& Elsevier]

The optical conductivity of monolayer and multilayer graphene in the terahertz spectral region is experimentally measured using terahertz time-domain spectroscopy. The stacking arrangement and the misorientation angle of each sample are determined by Raman spectroscopy. The chemical potential of each sample is measured using ultrafast midinfrared pump-probe spectroscopy to be 63 or 64 meV for all samples. The intraband scattering rate can be obtained by fitting the measured data with theoretical models. Other physical parameters, including carrier density, dc conductivity, and carrier mobility, of each sample can also be deduced from the theoretical fitting. The fitting results show the existence of misoriented or AA-stacked layers with an interaction energy of α1= 217 meV in our multilayer samples. Here we show that the scattering rate strongly depends on the stacking arrangement of the sample. High scattering rates and high optical conductivity are associated with AA-stacked samples, while lower ones are associated with misoriented multilayer graphene. This implies that the THz optoelectronic properties of multilayer graphene can be tuned by purposefully misorienting layers or employing different stacking schemes. [ABSTRACT FROM AUTHOR]

This paper presents some nonrandom distribution properties of two generalized cyclotomic binary sequences of length $$2p^{m}$$ constructed by Zhang et al. (Appl Algebra Eng Commun Comput 21:93-108, ). Using these properties we further study the $$k$$-error linear complexity and autocorrelation of these sequences. For some small values of $$k$$, the upper bounds on the $$k$$-error linear complexity are derived, which are far less than their linear complexity. Finally the bounds on the autocorrelation of these sequences are also presented. Our results show that there exist some drawbacks in application of these two sequences. [ABSTRACT FROM AUTHOR]

A novel gas−liquid−solid circulating fluidized bed adsorber for the separation of natural products or traditional Chinese medicines from extracts was successfully developed in this work. The hydrodynamics, axial dispersion, and mixing characteristics of phases and the adsorption and desorption of Ginkgo flavonoidsin macroporous resin particles with prepared extract were investigated. The results showed that with the increase of downer superficial gas velocity, the deviation degree of flow pattern from plug flow, and the liquid back-mixing in the downer were enhanced because the liquid Penumber of the downer became smaller while its axial dispersion coefficient got larger. Similar tends were found for the riser as the riser superficial gas velocity climbed. Compared with that of the downer, the flow in the riser was more close to plug flow. Investigations on the adsorption kinetics of macroporous resin particles showed that the adsorption separation of Ginkgo flavonoids from extract was controlled by the surface film mass transfer and intraparticle diffusion. Experimental results of adsorption separation of Ginkgo flavonoids in the three-phase circulating fluidized bed indicated that the air bubbles introduced in a liquid−solid circulating fluidized bed could enhance the adsorption and desorption processes, and smaller particles, lower superficial feed velocity, and adsorbate concentration were favorable for the three-phase circulating fluidized bed adsorption separation. The adsorption model of the downer and the desorption model of the riser were built, and they predicted the adsorption and desorption processes well. [ABSTRACT FROM AUTHOR]

Abstract: This paper studies the stability of the linear complexity of l-sequences. Let be an l-sequence with linear complexity attaining the maximum . A tight lower bound and an upper bound on , i.e., the minimal value k for which the k-error linear complexity of is strictly less than its linear complexity, are given. In particular, for an l-sequence based on a prime number of the form , where r is an odd prime number with primitive root 2, it is shown that is very close to r, which implies that this kind of l-sequences have very stable linear complexity. [ABSTRACT FROM AUTHOR]

Abstract: Nanocomposite of β-cyclodextrin and graphene sheet (β-CD/GS) was successfully prepared, which exhibited high stability in aqueous solution. When used in electrochemical detection of dopamine, the β-CD/GS modified carbon electrode showed low detection limit, broad linear range, along with good ability to suppress the background current from large excess ascorbic acid. The electrochemical reaction of dopamine on the β-CD/GS showed a mass diffusion-controlled process, which was different from the adsorption-controlled process on the unmodified graphene sheet. [Copyright &y& Elsevier]

Abstract: A novel strategy for the preparation of amperometric immunosensor for rapid determination of α-1-fetoprotein (AFP) in human serum has been developed. TiO2 nanoparticles (NPs) were prepared by solvothermal reaction using TiCl4 as raw materials and the mixture of ionic liquids and doubly distilled water as solvent. α-1-fetoprotein antibody (AFP Ab) was mixed with TiO2 NPs/chitsotan (CHIT) solution and immobilized onto the surface of a glassy carbon electrode. AFP (Ab) functionalized Au NPs were used as catalytic labels for the amperometric detection of AFP by means of the electrocatalyzed reduction of Au NPs to H2O2. The electrochemical behavior of the immunosensor was studied. Other experimental conditions such as pH, immunoreactions temperature and time were also studied. The prepared immunosensor offers an excellent amperometric response for AFP ranging from 1.0 to 160.0ng/mL with a detection limit of 0.1ng/mL. The result shows that the immunosensor displays rapid response, high sensitivity, good reproducibility and favorable stability. [Copyright &y& Elsevier]

A solvothermal method has been used to synthesize anatase-type TiO2 nanoparticles (NPs) using ionic liquid (1-ethyl-3-methylimidazolium-ethyl sulfate) as cosolvent and modifier. Palladium nanoparticles were electrodeposited on the glassy carbon (GC) electrode modified with synthesized TiO2 nanoparticles/chitosan film in the presence of glycin. The resulting amperometric sensor was used for direct determination of uric acid in human serum samples. Ionic liquid, TiO2, and Pd nanoparticles were characterized by infrared spectra (IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). This sensor offered an excellent detection for uric acid at 0.60 V in a linear response range of 4.42 × 10-5 to 7.98 × 10-3 M with a correlation coefficient of 0.997. The sensor displays rapid response, expanded linear response range, excellent repeatability, and excellent stability. [ABSTRACT FROM AUTHOR]

Natural gas in clathrate hydrates is regarded as a potential energy source that has received increased attention to optimize production strategies with controllable impacts on the environment. This paper investigates possible instability of a gently sloping reservoir of oceanic hydrates induced by gas production using the huff-puff method through a horizontal well. The geomechanical stability of the slope is analyzed within the framework of the limit equilibrium method by considering the dynamic change in the pore pressure and the strength parameters of the slope during gas production. The production process is simulated by a coupled analysis of heat and flow transport considering thermal effects of hydrate dissociation and formation, and the time-dependent pore pressure and strength parameters are attained from this analysis and passed to the slope stability analysis. Parametric studies are performed to screen the optimal production scenario under different site conditions. Being part of the huff-puff production process, thermal stimulation during the huff stage poses a risk of production-induced instability to the slope. Overpressure is the dominant cause for slope failure, and strength reduction due to hydrate dissociation plays a secondary role in the studied scenario. The production-induced slope failure likely takes place at a site with interbedded geological structures that promote overpressure expansion in a laterally extending band beneath the potential failure surface. Thus, the geological structures should be properly modelled in reservoir simulations, as they could impact the production effectiveness and geomechanical response of the reservoir remarkably. This study demonstrates a need for a multi-objective optimization procedure to seek the overall optimal production strategy, since the economically optimal option is not necessarily free of risk of production-induced geo-hazards. • A slope stability model is developed for slopes undergoing hydrate production. • The impact of hydrate huff-puff production on submarine slope instability is analyzed. • A concept of multi-objective optimization for hydrate production scheme is proposed. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the effects of various dendrimer shells on the intermolecular interactions of oligo(phenyleneethynylene)s (OPE) molecular wires in thin films have been studied. Electronic and fluorescence spectra showed that the dendrimer shells can effectively inhibit the aggregation of the molecular wires in both solutions and thin films. Tapping mode atomic force microscopy (TM-AFM) revealed that with the increase of dendrimer size, the film morphologies changed from fibrous to dendritic, indicating a strong shell-dependent molecular packing. This work demonstrated that such ‘core–shell’ molecular design strategy can be used to precisely tailor the molecular environment surrounding the molecular wires. [Copyright &y& Elsevier]

The article provides information on the history and genealogy of disco music in the U.S. The seventies dance culture, otherwise known as Disco Era from 1973 to 1979, has accordingly led to music like hip-hop, electronica, techno, and garage, among others in the 1880's. With reference to this, such musical style is likewise noted to have eventually shown the unspecified detail of disco and its complex evolution. On the other hand, disco, with its post-medium format, is likely believed to have greatly influenced the Studio 54, the Paradise Garage, and the Loft.

This paper examines the dynamic correlation structure between A-share and B-share stock returns based on three different measures of correlation coefficients. Testing the models by employing daily stock-return data for the period from 1996 through 2003, we reach the following empirical conclusions. First, the correlation coefficients between A-share and B-share stock returns are time varying. Second, the dynamic path of the correlation coefficients indicates that the correlation coefficients are significantly correlated with the trend factor. Third, there is a substantial spillover effect from the Asian crisis to Chinese stock-return dynamic correlations. Fourth, the evidence suggests that the time-varying correlations are significantly associated with excessive trading activity as measured by excessive trading volumes and high-low price differentials. Fifth, the correlation between A-share and B-share markets has increased since the relaxation of the restriction on B-share market investments by domestic investors. [ABSTRACT FROM AUTHOR]

The article presents information on string matching algorithm tools which is used for scanning purpose to maintain security of data on computer networks. The String matching is a critical element of detection systems because it lets a system make decisions based actual content flowing through network. The article authors' say that Intrusion detection systems must scan every byte of every packet to find the signatures of known hackers and it requires very high throughput methods for string matching. The authors says that they adopted an approach that relies on a powerful special-purpose architecture working in conjunction with novel string-matching algorithms specially optimized for this architecture. The key to achieve high performance and high efficiency is to build many tiny state machines. The network-based intrusion detection systems require sensors that perform real-time monitoring of network packets by comparing network traffic against a signature database or by triggering intrusion alarms.

SPECK and SPARX are two kinds of block ciphers with an ARX structure. In this paper, we use the SAT-based automatic search tool to search for linear approximations of these two ARX ciphers. As a result, we find a linear approximation for 17-round SPECK128, which covers one more round than previous work. Based on this linear approximation, we propose improved linear cryptanalysis for 19-round SPECK128/192 and 20-round SPECK128/256, which cover one more round than previous work. For ARX cipher SPARX, we find an optimal linear approximation for 13-round SPARX-64, which covers three more rounds than previous work. We also find an optimal linear approximation for 10-round SPARX-128, which covers two more rounds than previous work. Furthermore, we find a linear approximation for 14-round SPARX-128 by splicing two short linear approximations, which covers four more rounds than previous work. Based on these linear approximations, we propose linear cryptanalysis for 15-round SPARX-64/128, 15-round SPARX-128/128 and 16-round SPARX-128/256. [ABSTRACT FROM AUTHOR]

This note employs a unifying approach to examine the impacts of various forms of business taxes on an agroindustrial firm's choice of plant location under uncertainty. It shows that, if the production function is homogeneous of degree one, then the lump-sum and proportional profit taxes are spatially neutral for any risk-averse agroindustrial firm operating with a random raw material price. For cases where the taxes are spatially non-neutral, unambiguous effects regarding an agroindustrial firm's locational response to the imposition of business taxes have also been provided. In addition, we demonstrate that the spatial effects of business taxes on agroindustrial firms differ sharply from their non-agroindustrial counterparts. [ABSTRACT FROM AUTHOR]

This paper reexamines the welfare implications of three pricing regimes (mill, uniform, and discriminatory) for a monopoly. Assuming linear demand and constant marginal costs, I show that with the introduction of endogenous location choice, uniform delivered pricing may provide the highest social welfare when demands in different markets are sufficiently heterogeneous; whereas discriminatory pricing always dominates uniform pricing when demands in different markets are similar. [ABSTRACT FROM AUTHOR]

Discusses results of a survey assessing patient perception of time spent with the physician in an ambulatory internal medicine clinical setting. Duration of patient visits; Comparison of patient and physician feeling of being rushed; Comparison of estimated versus actual time spent with the physician.

The flash-sintering behavior of Al 2 O 3 -GdAlO 3 -ZrO 2 powders with a eutectic composition was investigated. The flash-sintered bulks contained two distinct regions: a normally sintered region and a channel region. The Al 2 O 3 -GdAlO 3 -ZrO 2 eutectic microstructure observed in the channel region was caused by current localization. We suggest that the eutectic temperature is reached locally in some regions during flash sintering, thus leading to the formation of a eutectic microstructure. The produced eutectic microstructure exhibited high hardness (17.7 GPa) and relatively high fracture toughness (4.3 MPa m1/2). The results suggest that the current localization that occurs in flash sintering can be used to prepare eutectic ceramics. [ABSTRACT FROM AUTHOR]

Examines and analyzes the total factor productivity growth (TFPG) performance of individual service industries in Singapore. Reason the concept of TFPG is important to Singapore; Information on Singapore's service sector; Details on capital and labor input in Singapore.

Polyphenols based bioactive compounds from vegetables and fruits are known for impressive antioxidant activity. Ingestion of these antioxidants may promote human health against cardiovascular diseases and cancer. Mango is a popular tropical fruit with special taste, high nutritional value and health-enhancing metabolites. The aim was to investigate the diversity of phytochemicals between two mango cultivars of china at three stages of fruit maturity. We used ESI-QTRAP-MS/MS approach to characterize comprehensively the metabolome of two mango cultivars named Hongguifei (HGF) and Tainong (TN). HPLC was used to quantify selected catechin based phenolic compounds. Moreover, real-time qPCR was used to study the expression profiles of two key genes (ANR and LAR) involved in proanthocyanidin biosynthesis from catechins and derivatives. A total of 651 metabolites were identified, which include at least 257 phenolic compounds. Higher number of metabolites were differentially modulated in peel as compared to pulp. Overall, the relative quantities of amino acids, carbohydrates, organic acids, and other metabolites were increased in the pulp of TN cultivar. While the contents of phenolic compounds were relatively higher in HGF cultivar. Moreover, HPLC based quantification of catechin and derivatives exhibited cultivar specific variations. The ANR and LAR genes exhibited an opposite expression profile in both cultivars. Current study is the first report of numerous metabolites including catechin-based derivatives in mango fruit. These findings open novel possibilities for the use of mango as a source of bioactive compounds. [ABSTRACT FROM AUTHOR]

We report herein the development of palladium‐catalyzed deacylative deuteration of arylketone oxime ethers. This protocol features excellent functional group tolerance, heterocyclic compatibility, and high deuterium incorporation levels. Regioselective deuteration of some biologically important drugs and natural products are showcased via Friedel–Crafts acylation and subsequent deacylative deuteration. Vicinal meta‐C−H bond functionalization (including fluorination, arylation, and alkylation) and para‐C−H bond deuteration of electro‐rich arenes are realized by using the ketone as both directing group and leaving group, which is distinct from aryl halide in conventional dehalogenative deuteration. [ABSTRACT FROM AUTHOR]

We report herein the development of palladium‐catalyzed deacylative deuteration of arylketone oxime ethers. This protocol features excellent functional group tolerance, heterocyclic compatibility, and high deuterium incorporation levels. Regioselective deuteration of some biologically important drugs and natural products are showcased via Friedel–Crafts acylation and subsequent deacylative deuteration. Vicinal meta‐C−H bond functionalization (including fluorination, arylation, and alkylation) and para‐C−H bond deuteration of electro‐rich arenes are realized by using the ketone as both directing group and leaving group, which is distinct from aryl halide in conventional dehalogenative deuteration. [ABSTRACT FROM AUTHOR]

Urinary metabolomics coupled with GC-MS has become a leading technology in newborn screening. Because of non-specificity, complexity and high-variety in clinical characteristics and metabolomic profiling, the simultaneous detection of multiple inherited metabolic diseases (IMDs) is often challenging. As a substantial health problem, a competent chemometrics multi-class classification system for the early detection and diagnosis of IMDs would be advantageous. Beyond the commonly used binarization techniques of one-against-all (OAA) and one-against-one (OAO), an exhaustive and parallel half-against-half (EPHAH) decomposition is described in this study to deal with multi-class classification. For a K -class problem, EPHAH employs uniform class binary partition strategy to induce the binary classifier evaluating a half of K classes against the other half. With K -class problem exhaustively decomposed into all uniform binary partitions of K classes, EPHAH parallelly arranges the corresponding binary classifiers and aggregates their outputs to obtain the multi-class prediction using max-wins voting strategy. Based on orthogonal partial least squares discriminant analysis (OPLS-DA) with feature selection using particle swarm optimization (PSO) algorithm, EPHAH is investigated by GC-MS urinary metabolomics data among healthy controls and 9 most common IMDs. The results show that EPHAH enables a complete learning of the complex multi-class decision boundaries of 10 classes, exhibiting significant superiority in classification accuracies over OAA, OAO and traditional HAH. Meanwhile, compared with OAO using the same max-wins voting strategy, EPHAH gives an effective break of the tie problem in classification and enhanced resolution in votes. • An exhaustive and parallel half-against-half (EPHAH) decomposition was proposed for multi-class classification. • EPHAH involved uniform class binary partition and parallel arrangement with exhaustive decomposition of K -class problem. • EPHAH coupled with OPLS-DA profiled GC-MS urinary metabolomics data of multi-class IMDs with desired results. • A competent system for multi-class IMDs simultaneous detection was developed, aiding their early detection and diagnosis. [ABSTRACT FROM AUTHOR]

Rayleigh scattering signals, not conforming bilinear and trilinear structure of spectral excitation–emission matrices (EEMs), significantly increases the difficulty of spectral resolution. To eliminate or reduce the interference of Rayleigh scattering, we propose missing data recovery (MDR) coupled with principal component analysis (PCA) or parallel factor analysis (PARAFAC) as a novel strategy for Rayleigh scattering correction and corresponding EEM decomposition. MDR treats the scattering data as missing by weighting them as zeros to remove Rayleigh scattering signals thoroughly. Then, sample signals are dramatically recovery in the scattering missing region during rapid iterative process of PCA or PARAFAC to repair bilinearity and trilinearity of EEMs. For significant Rayleigh scattering leading to severe signal loss, profile constraint on both of excitation and emission spectra following fluorescence spectral laws is further proposed for MDR-PCA and MDR-PARAFAC. It is so as to avoid mathematical reasonable but chemical meaningless solutions. The results reveal MDR-PCA and MDR-PARAFAC enable robust Rayleigh scattering correction and EEM decomposition both for simulated and practical data sets. Without the need of any specific priori knowledge and pretreatment such as wavelength selection, it therefore suggests great potential of the proposed method to be a generalized strategy for robust Rayleigh scattering correction and spectral resolution of EEMs. • A novel Missing data recovery (MDA) strategy for Rayleigh scattering correction. • Good performance obtained by MDA coupled with PCA or PARAFAC for EEM analysis. • Profile constraint is further proposed for avoiding chemical meaningless solution. [ABSTRACT FROM AUTHOR]

miRNA has been a research hotspot in recent years and its scope of action is very wide, involving the regulation of cell proliferation, differentiation, apoptosis, and other biological behaviors. This study intends to explore the role of miRNA in the lipid metabolism and development of Wilms tumor (WT) by detecting and analyzing the differences in the expression profiles of miRNAs between the tumor and adjacent normal tissue. Gene detection was performed in tumor tissues and adjacent normal tissues of three cases of WT to screen differentially expressed miRNAs (DEMs). According to our previous research, FASN, which participates in the lipid metabolism pathway, may be a target of WT. The starBase database was used to predict FASN-targeted miRNAs. The above two groups of miRNAs were intersected to obtain FASN-targeted DEMs and then GO Ontology (GO) functional enrichment analysis of FASN-targeted DEMs was performed. Finally, the FASN-targeted DEMs were compared and further verified by qRT‒PCR. Through gene sequencing and differential analysis, 287 DEMs were obtained, including 132 upregulated and 155 downregulated miRNAs. The top ten DEMs were all downregulated. Fourteen miRNAs targeted by the lipid metabolism-related gene FASN were predicted by starBase. After intersection with the DEMs, three miRNAs were finally obtained, namely, miR-107, miR-27a-3p, and miR-335-5p. GO enrichment analysis was mainly concentrated in the Parkin-FBXW7-Cul1 ubiquitin ligase complex and response to prostaglandin E. Further experimental verification showed that miR-27a-3p was significantly correlated with WT (P = 0.0018). Imbalanced expression of miRNAs may be involved in the occurrence and development of WT through lipid metabolism. The expression of miR-27a-3p is related to the malignant degree of WT, and it may become the target of diagnosis, prognosis, and treatment of WT in the later stage. [ABSTRACT FROM AUTHOR]

Gas hydrates dissociation could induce or trigger submarine landslides, especially in upper continental slopes where hydrates are vulnerable to natural and artificial perturbations. This work investigates destabilization mechanisms of an upper continental slope undergoing hydrate dissociation and identifies spatiotemporal failure modes influenced by characteristics of the overburden above the hydrate-bearing layer (i.e. the hydrate reservoir). A Thermo-Hydro-Chemical coupled numerical model of transient pore pressure induced by hydrate dissociation is coupled with the limit equilibrium slope analysis method to study the spatiotemporal evolution of the potential sliding plane and to calculate the corresponding factor of safety. The results suggest that overpressure generated by the liberated fluid from hydrate dissociation is the primary reason for instability in a gentle marine slope. The study identifies three sliding modes, namely co-melting non-interface sliding, co-melting interface sliding, and post-melting non-interface sliding, depending on the overburden's characteristics, including overburden thickness, permeability, and cohesion. Co-melting non-interface sliding takes place during hydrate dissociation if the hydrate reservoir underlies a thin, pervious and low-cohesion overburden cover. For less permeable and more cohesive overburdens, the potential sliding plane is deeper and co-melting interface sliding could be triggered due to overpressure developed at the reservoir-overburden interface. If the hydrate reservoir is covered by a thick, low-permeability and slightly cohesive overburden, post-melting non-interface sliding could occur after the hydrates are completely dissociated. This failure is delayed, because the gas/water trapped at the interface during hydrate dissociation is insufficient to trigger instability due to very high overburden stresses. However, as the gas migrates upwards over time and encounters a weak zone in the overburden deposits, failure could happen within the overburden deposits even after hydrate dissociation stops. The findings help to improve our fundamental understanding about the destabilization mechanism and failure modes of the continental slopes undergoing hydrate dissociation, and to delineate the vulnerable configurations of the slopes. • A slope stability model is developed for slopes undergoing hydrate dissociation. • The transient pore pressure is computed from a THC coupled analysis. • Three failure modes depending on overburden characteristics are identified. [ABSTRACT FROM AUTHOR]

Background: Lactate dehydrogenase (LDH) is a critical metabolic enzyme. LDH A (LDHA) overexpression is a hallmark of aggressive malignancies and has been linked to tumour initiation, reprogramming and progression in multiple tumour types. However, successful LDHA inhibition strategies have not materialised in the translational and clinical space. We sought to develop a rational strategy for LDHA suppression in the context of solid tumour treatment.Methods: We utilised a doxycycline-inducible short hairpin RNA (shRNA) system to generate LDHA suppression. Lactate and LDH activity levels were measured biochemically and kinetically using hyperpolarised 13C-pyruvate nuclear magnetic resonance spectroscopy. We evaluated effects of LDHA suppression on cellular proliferation and clonogenic survival, as well as on tumour growth, in orthotopic models of anaplastic thyroid carcinoma (ATC) and head and neck squamous cell carcinoma (HNSCC), alone or in combination with radiation.Results: shRNA suppression of LDHA generated a time-dependent decrease in LDH activity with transient shifts in intracellular lactate levels, a decrease in carbon flux from pyruvate into lactate and compensatory shifts in metabolic flux in glycolysis and the Krebs cycle. LDHA suppression decreased cellular proliferation and temporarily stunted tumour growth in ATC and HNSCC xenografts but did not by itself result in tumour cure, owing to the maintenance of residual viable cells. Only when chronic LDHA suppression was combined with radiation was a functional cure achieved.Conclusions: Successful targeting of LDHA requires exquisite dose and temporal control without significant concomitant off-target toxicity. Combinatorial strategies with conventional radiation are feasible as long as the suppression is targeted, prolonged and non-toxic. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction reaction (CO2RR) over Cu catalysts exhibits enormous potential for efficiently converting CO2 to ethylene (C2H4). However, achieving high C2H4 selectivity remains a considerable challenge due to the propensity of Cu catalysts to undergo structural reconstruction during CO2RR. Herein, we report an in situ molecule modification strategy that involves tannic acid (TA) molecules adaptive regulating the reconstruction of a Cu‐based material to a pathway that facilitates CO2 reduction to C2H4 products. An excellent Faraday efficiency (FE) of 63.6 % on C2H4 with a current density of 497.2 mA cm−2 in flow cell was achieved, about 6.5 times higher than the pristine Cu catalyst which mainly produce CH4. The in situ X‐ray absorption spectroscopy and Raman studies reveal that the hydroxyl group in TA stabilizes Cuδ+ during the CO2RR. Furthermore, theoretical calculations demonstrate that the Cuδ+/Cu0 interfaces lower the activation energy barrier for *CO dimerization, and hydroxyl species stabilize the *COH intermediate via hydrogen bonding, thereby promoting C2H4 production. Such molecule engineering modulated electronic structure provides a promising strategy to achieve highly selective CO2 reduction to value‐added chemicals. [ABSTRACT FROM AUTHOR]