bluuebunny/crossref_metadata_2025 huggingface dataset:
Portal, but not lobular, macrophages express matrix metalloproteinase‐9: association with the ductular reaction and fibrosis in chronic hepatitis C
Authors: Gadd Victoria L. , Melino Michelle , Roy Sandrine , Horsfall Leigh , O'Rourke Peter , Williams Millicent R. , Irvine Katharine M. , Sweet Matthew J. , Jonsson Julie R. , Clouston Andrew D. , Powell Elizabeth E.
Published: November 2012

Background

Liver macrophages are a heterogeneous cell population that produces factors involved in fibrogenesis and matrix turnover, including matrix metalloproteinase (MMP) ‐9. During liver injury, their close proximity to hepatic progenitor cells and the ductular reaction may enable them to regulate liver repair and fibrosis.

Aims

To enumerate and characterise liver macrophages in patients with chronic hepatitis C, to determine whether a distinct population of macrophages is associated with the ductular reaction and portal fibrosis.

Methods

Immunostaining for macrophage markers (CD68, CD163, CCR2), the ductular reaction (keratin‐7) and MMP‐9 was performed in liver biopsy sections from patients with chronic hepatitis C virus (HCV) (n = 85).

Results

Portal tracts were more densely populated with macrophages (10.5 ± 0.36 macrophages/HPF) than lobules (7.2 ± 0.16 macrophages/HPF, P < 0.001) and macrophages were found in close proximity to the ductular reaction. ≥30% of portal and periductal macrophages expressed MMP‐9 and these were significantly associated with increasing stage of fibrosis (rs = 0.58, 0.68, respectively, both P < 0.001). In contrast, MMP‐9+ macrophages were largely absent in lobular regions and non‐diseased liver. Hepatic MMP‐9 mRNA levels and gelatinolytic activity were significantly associated with stage of fibrosis (rs = 0.47, rs = 0.89, respectively, both P < 0.001). Furthermore, a second distinct CCR2+ macrophage population was localised to the centrilobular regions and was predominantly absent from portal and periductal areas.

Conclusions

These findings demonstrate significant regional differences in macrophage phenotypes, suggesting that there are at least two populations of liver macrophages. We propose that these populations have distinct contributions to the pathogenesis of chronic HCV‐related liver disease.
Virulence factor regulator (Vfr) controls virulence‐associated phenotypes in Pseudomonas syringae pv. tabaci 6605 by a quorum sensing‐independent mechanism
Authors: Taguchi Fumiko , Ichinose Yuki
Published: November 2012

Virulence factor regulator (Vfr) is a member of the cyclic 3′,5′‐adenosine monophosphate (cAMP) receptor proteins that regulate the expression of many important virulence genes in Pseudomonas aeruginosa. The role of Vfr in pathogenicity has not been elucidated fully in phytopathogenic bacteria. To investigate the function of Vfr in Pseudomonas syringae pv. tabaci 6605, the vfr gene was disrupted. The virulence of the vfr mutant towards host tobacco plants was attenuated significantly, and the intracellular cAMP level was decreased. The vfr mutant reduced the expression of flagella‐, pili‐ and type III secretion system‐related genes and the defence response in nonhost Arabidopsis leaves. Furthermore, the expression levels of achromobactin‐related genes and the iron uptake ability were decreased, suggesting that Vfr regulates positively these virulence‐related genes. In contrast, the vfr mutant showed higher tolerance to antimicrobial compounds as a result of the enhanced expression of the resistance–nodulation–division family members, the mexA, mexB and oprM genes. We further demonstrated that the mutant strains of vfr and cyaA, an adenylate cyclase gene responsible for cAMP synthesis, showed a similar phenotype, suggesting that Vfr regulates virulence factors in a cAMP‐dependent manner. Because there was no significant difference in the production of acylhomoserine lactone (AHL) quorum sensing molecules in the wild‐type, vfr and cyaA mutant strains, Vfr might control important virulence factors by an AHL‐independent mechanism in an early stage of infection by this bacterium.
Gingival fibroblast responsiveness is differentially affected by Porphyromonas gingivalis: implications for the pathogenesis of periodontitis
Authors: Scheres N. , Crielaard W.
Published: November 2012

In periodontitis, tissue damage results mainly from aberrant host responses to oral microorganisms. Fibroblasts can play an important role in this. Gingival fibroblasts do not develop tolerance against the lipopolysaccharide of Porphyromonas gingivalis, a keystone pathogen in periodontitis, which may partly explain the persistence of inflammation. However, besides lipopolysaccharide, live P. gingivalis possess numerous virulence traits to impair host‐responses. We hypothesized that fibroblast‐responsiveness to a bacterial challenge could be affected by live P. gingivalis. We investigated if inflammatory responses of gingival fibroblasts to P. gingivalis were altered, when the fibroblasts had encountered P. gingivalis previously. On consecutive days, primary human gingival fibroblasts were challenged twice for 6 h with live P. gingivalis, or fibroblasts were preincubated for 24 h with a lower concentration of live P. gingivalis and re‐challenged for 6 h with a higher concentration. As the P. gingivalis capsule and proteases are involved in modulating host responses, we used encapsulated P. gingivalis W83 and a non‐encapsulated mutant, and P. gingivalis ATCC33277 and a lys‐gingipain and arg‐gingipain mutant, to challenge fibroblasts. With all P. gingivalis‐strains, interleukin‐8 and monocyte chemoattractant protein‐1 responses to the second challenge were less strong in fibroblasts that had been challenged with P. gingivalis before. These lower responses might correspond with higher interleukin‐1 receptor agonist expression. Fibroblast responses to a second challenge were not influenced by 24 h preincubation. Reduced chemokine responses after consecutive potent P. gingivalis challenges indicate that gingival fibroblast responsiveness is affected by a previous bacterial encounter. In periodontitis, such reduced chemokine responses may impair chemotaxis and clearance of oral microorganisms, thereby leading to prolonged inflammatory responses and tissue damage.
Breaking the cycle: how light, CO2 and O2 affect plant respiration
Authors: GRIFFIN KEVIN L. , HESKEL MARY
Published: November 2012

This article comments on: Short‐term effects of CO2 and O2 on citrate metabolism in illuminated leaves
Linear Congenital Molluscum Contagiosum on the Coccygeal Region
Authors: Ujiie Hideyuki , Aoyagi Satoru , Hirata Yu , Osawa Rinko , Shimizu Hiroshi
Published: November 2012

Congenital molluscum contagiosum is rare but has been reported previously. We present a unique case of linear congenital molluscum on the coccygeal region. To make a correct diagnosis, avoid unnecessary examination, and start appropriate treatment as soon as possible, it is beneficial for dermatologists to be aware that molluscum contagiosum can present at birth and can be linear.
Wiskott‐Aldrich Syndrome Caused by a New Mutation Associated with Multifocal Dermal Juvenile Xanthogranulomas
Authors: Jesenak Milos , Plamenova Ivana , Plank Lukas , Banovcin Peter
Published: November 2012

Wiskott‐Aldrich syndrome is a rare X‐linked primary immunodeficiency clinically characterized by the triad of microthrombocytopenia, immunodeficiency, and eczema. Juvenile xanthogranuloma is a well‐recognized benign disorder of infancy and early childhood from the group of non‐Langerhans cell histiocytoses, with a good prognosis and spontaneous involution. We report a boy with Wiskott‐Aldrich syndrome caused by a new, not previously described mutation associated with multifocal juvenile xanthogranuloma.
Photodynamic Tumor Eradication With a Novel Targetable Photosensitizer: Strong Vascular Effects and Dependence on Treatment Repetition Versus Potentiation
Authors: Savellano Mark D. , Owusu‐Brackett Nicci , Son Ji , Ganga Tanay , Leung Nadia L. , Savellano Dagmar H.
Published: November 2012

A novel pyropheophorbide‐a (PPa) derivative, Ac‐sPPp, was developed in our lab for targeted photodynamic therapy (PDT) and combination therapies. Its versatile peptide moiety, high water‐solubility, amphiphilicity, and micellar aggregation allow efficient coupling to targeting moieties and convenient mixing with other therapeutics. Photosensitizer immunoconjugate (PIC) targeted PDT, using Ac‐sPPp conjugated to therapeutic anti‐epidermal growth factor receptor (EGFR) antibody cetuximab, and PDT + chemotherapy combination treatment, using Ac‐sPPp mixed with stealth liposomal doxorubicin (Doxil), were investigated as promising strategies for potentiating PDT and improving target specificity. Passively targeted PDT with Ac‐sPPp only or surfactant‐solubilized PPa was also investigated for comparison. The A‐431 human vulvar squamous cell carcinoma, xenografted in nude mice, was chosen as a tumor model because of its high EGFR expression and sensitivity to liposomal doxorubicin in vitro. Fluorescence imaging and PDT experiments showed that Ac‐sPPp formulations circulated far longer and provided superior tumor contrast and superior tumor control compared to PPa. Strong PDT vascular effects were observed by laser Doppler imaging regardless of whether Ac‐sPPp was passively or actively targeted. Passively targeted Ac‐sPPp PDT gave equivalent or better tumor control than PIC‐targeted PDT or PDT + Doxil combination therapy, and when treatments were repeated, it also yielded the highest cure rate.
Preparation and Characterization of Ag‐Loaded SmVO4 for Photocatalysis Application
Authors: Li Tingting , He Yiming , Cai Jun , Lin Hongjun , Luo Mengfei , Zhao Leihong
Published: November 2012

Ag/SmVO4 composite photocatalysts were synthesized and characterized by BET, XRD, Raman, SEM, TEM, XPS and DRS techniques. Their photocatalytic activities were determined by oxidative decomposition of RhB in aqueous solution under visible light irradiation. The charge separation efficiency was evaluated by the photocurrent‐time and ֹOH‐trapping experiments. The results revealed that the loaded Ag species greatly improved the efficiency in charge separation, and thus led to enhanced photocatalytic activities compared with that of the pure SmVO4. The sample contained 0.5 wt% Ag and heated at 500°C presents the highest photoactivity.
Comparison of manual versus automatic continuous positive airway pressure titration and the development of a predictive equation for therapeutic continuous positive airway pressure in Chinese patients with obstructive sleep apnoea
Authors: Luo Jiaying , Xiao Sichang , Qiu Zhihui , Song Ning , Luo Yuanming
Published: November 2012

Background and objective

Whether the therapeutic nasal continuous positive airway pressure (CPAP) derived from manual titration is the same as derived from automatic titration is controversial. The purpose of this study was to compare the therapeutic pressure derived from manual titration with automatic titration.

Methods

Fifty‐one patients with obstructive sleep apnoea (OSA) (mean apnoea/hypopnoea index (AHI) = 50.6 ± 18.6 events/h) who were newly diagnosed after an overnight full polysomnography and who were willing to accept CPAP as a long‐term treatment were recruited for the study. Manual titration during full polysomnography monitoring and unattended automatic titration with an automatic CPAP device (REMstar Auto) were performed. A separate cohort study of one hundred patients with OSA (AHI = 54.3 ± 18.9 events/h) was also performed by observing the efficacy of CPAP derived from manual titration.

Results

The treatment pressure derived from automatic titration (9.8 ± 2.2 cmH2O) was significantly higher than that derived from manual titration (7.3 ± 1.5 cmH2O; P < 0.001) in 51 patients. The cohort study of 100 patients showed that AHI was satisfactorily decreased after CPAP treatment using a pressure derived from manual titration (54.3 ± 18.9 events/h before treatment and 3.3 ± 1.7 events/h after treatment; P < 0.001).

Conclusions

The results suggest that automatic titration pressure derived from REMstar Auto is usually higher than the pressure derived from manual titration.
The Polycomb group protein MEDEA and the DNA methyltransferase MET1 interact to repress autonomous endosperm development in Arabidopsis
Authors: Schmidt Anja , Wöhrmann Heike J. P. , Raissig Michael T. , Arand Julia , Gheyselinck Jacqueline , Gagliardini Valeria , Heichinger Christian , Walter Joern , Grossniklaus Ueli
Published: November 2012

In flowering plants, double fertilization of the female gametes, the egg and the central cell, initiates seed development to give rise to a diploid embryo and the triploid endosperm. In the absence of fertilization, the FERTILIZATION‐INDEPENDENT SEED Polycomb Repressive Complex 2 (FIS‐PRC2) represses this developmental process by histone methylation of certain target genes. The FERTILIZATION‐INDEPENDENT SEED (FIS) class genes MEDEA (MEA) and FERTILIZATION‐INDEPENDENT ENDOSPERM (FIE) encode two of the core components of this complex. In addition, DNA methylation establishes and maintains the repression of gene activity, for instance via DNA METHYLTRANSFERASE1 (MET1), which maintains methylation of symmetric CpG residues. Here, we demonstrate that Arabidopsis MET1 interacts with MEA in vitro and in a yeast two‐hybrid assay, similar to the previously identified interaction of the mammalian homologues DNMT1 and EZH2. MET1 and MEA share overlapping expression patterns in reproductive tissues before and after fertilization, a prerequisite for an interaction in vivo. Importantly, a much higher percentage of central cells initiate endosperm development in the absence of fertilization in mea‐1/MEA; met1‐3/MET1 as compared to mea‐1/MEA mutant plants. In addition, DNA methylation at the PHERES1 and MEA loci, imprinted target genes of the FIS‐PRC2, was affected in the mea‐1 mutant compared with wild‐type embryos. In conclusion, our data suggest a mechanistic link between two major epigenetic pathways involved in histone and DNA methylation in plants by physical interaction of MET1 with the FIS‐PRC2 core component MEA. This concerted action is relevant for the repression of seed development in the absence of fertilization.
Auxin signal transcription factor regulates expression of the brassinosteroid receptor gene in rice
Authors: Sakamoto Tomoaki , Morinaka Yoichi , Inukai Yoshiaki , Kitano Hidemi , Fujioka Shozo
Published: November 2012

The phytohormones auxins and brassinosteroids are both essential regulators of physiological and developmental processes, and it has been suggested that they act inter‐dependently and synergistically. In rice (Oryza sativa), auxin co‐application improves the brassinosteroid response in the rice lamina inclination bioassay. Here, we showed that auxins stimulate brassinosteroid perception by regulating the level of brassinosteroid receptor. Auxin treatment increased expression of the rice brassinosteroid receptor gene OsBRI1. The promoter of OsBRI1 contains an auxin‐response element (AuxRE) that is targeted by auxin‐response factor (ARF) transcription factors. An AuxRE mutation abolished the induction of OsBRI1 expression by auxins, and OsBRI1 expression was down‐regulated in an arf mutant. The AuxRE motif in the OsBRI1 promoter, and thus the transient up‐regulation of OsBRI1 expression caused by treatment with indole‐3‐acetic acid, is essential for the indole‐3‐acetic acid‐induced increase in sensitivity to brassinosteroids. These findings demonstrate that some ARFs control the degree of brassinosteroid perception required for normal growth and development in rice. Although multi‐level interactions between auxins and brassinosteroids have previously been reported, our findings suggest a mechanism by which auxins control cellular sensitivity to brassinosteroids, and further support the notion that interactions between auxins and brassinosteroids are extensive and complex.
SIMPLE LEAF3 encodes a ribosome‐associated protein required for leaflet development in Cardamine hirsuta
Authors: Kougioumoutzi Evangelia , Cartolano Maria , Canales Claudia , Dupré Mhairi , Bramsiepe Jonathan , Vlad Daniela , Rast Madlen , Ioio Raffaele Dello , Tattersall Alex , Schnittger Arp , Hay Angela , Tsiantis Miltos
Published: November 2012

Leaves show considerable variation in shape, and may be described as simple, when the leaf is entire, or dissected, when the leaf is divided into individual leaflets. Here, we report that the SIMPLE LEAF3 (SIL3) gene is a novel determinant of leaf shape in Cardamine hirsuta – a dissected‐leaved relative of the simple‐leaved model species Arabidopsis thaliana. We show that SIL3 is required for leaf growth and leaflet formation but leaf initiation is less sensitive to perturbation of SIL3 activity. SIL3 is further required for KNOX (knotted1‐like homeobox) gene expression and localized auxin activity maxima, both of which are known to promote leaflet formation. We cloned SIL3 and showed that it encodes RLI2 (RNase L inhibitor 2), an ATP binding cassette‐type ATPase with important roles in ribosome recycling and translation termination that are conserved in eukaryotes and archaea. RLI mutants have not been described in plants to date, and this paper highlights the potential of genetic studies in C. hirsuta to uncover novel gene functions. Our data indicate that leaflet development is sensitive to perturbation of RLI2‐dependent aspects of cellular growth, and link ribosome function with dissected‐leaf development.
Comparison of hematologic, biochemical, and coagulation parameters in α1,3‐galactosyltransferase gene‐knockout pigs, wild‐type pigs, and four primate species
Authors: Ekser Burcin , Bianchi John , Ball Suyapa , Iwase Hayato , Walters Anneke , Ezzelarab Mohamed , Veroux Massimiliano , Gridelli Bruno , Wagner Robert , Ayares David , Cooper David K.C.
Published: November 2012

Ekser B, Bianchi J, Ball S, Iwase H, Walters A, Ezzelarab M, Veroux M, Gridelli B, Wagner R, Ayares D, Cooper DKC. Comparison of hematologic, biochemical, and coagulation parameters in α1,3‐galactosyltransferase gene‐knockout pigs, wild‐type pigs, and four primate species. Xenotransplantation 2012; 19: 342–354. © 2012 John Wiley & Sons A/S.

Abstract:  Background:  The increasing availability of genetically engineered pigs is steadily improving the results of pig organ and cell transplantation in non‐human primates (NHPs). Current techniques offer knockout of pig genes and/or knockin of human genes. Knowledge of normal values of hematologic, biochemical, coagulation, and other parameters in healthy genetically engineered pigs and NHPs is important, particularly following pig organ transplantation in NHPs. Furthermore, information on parameters in various NHP species may prove important in selecting the optimal NHP model for specific studies.

Methods:  We have collected hematologic, biochemical, and coagulation data on 71 α1,3‐galactosyltransferase gene‐knockout (GTKO) pigs, 18 GTKO pigs additionally transgenic for human CD46 (GTKO.hCD46), four GTKO.hCD46 pigs additionally transgenic for human CD55 (GTKO.hCD46.hCD55), and two GTKO.hCD46 pigs additionally transgenic for human thrombomodulin (GTKO.hCD46.hTBM).

Results:  We report these data and compare them with similar data from wild‐type pigs and the three major NHP species commonly used in biomedical research (baboons, cynomolgus, and rhesus monkeys) and humans, largely from previously published reports.

Conclusions:  Genetic modification of the pig (e.g., deletion of the Gal antigen and/or the addition of a human transgene) (i) does not result in abnormalities in hematologic, biochemical, or coagulation parameters that might impact animal welfare, (ii) seems not to alter metabolic function of vital organs, although this needs to be confirmed after their xenotransplantation, and (iii) possibly (though, by no means certainly) modifies the hematologic, biochemical, and coagulation parameters closer to human values. This study may provide a good reference for those working with genetically engineered pigs in xenotransplantation research and eventually in clinical xenotransplantation.
Sport injuries and illnesses during the first Winter Youth Olympic Games 2012 in Innsbruck, Austria
Authors: Ruedl Gerhard , Schobersberger Wolfgang , Pocecco Elena , Blank Cornelia , Engebretsen Lars , Soligard Torbjørn , Steffen Kathrin , Kopp Martin , Burtscher Martin
Published: November 2012

Background

Data on the injury and illness risk among young elite athletes are of utmost importance, because injuries and illnesses can counter the beneficial effects of sports participation at a young age, if children or adolescents are unable to continue to participate because of residual effects of injury or chronic illness.

Objective

To analyse the frequencies and characteristics of injuries and illnesses during the 2012 Innsbruck Winter Youth Olympic Games (IYOG).

Methods

We employed the International Olympic Committee (IOC) injury surveillance system for multisport events, which was updated for the Winter Olympic Games in Vancouver 2010. All National Olympic Committees (NOCs) were asked to report the daily occurrence (or non-occurrence) of newly sustained injuries and illnesses on a standardised reporting form. In addition, information on athletes treated for injuries and illnesses by the Local Organizing Committee medical services was retrieved from the medical centre at the Youth Olympic Village and from the University hospital in Innsbruck.

Results

Among the 1021 registered athletes (45% women, 55% men) from 69 NOCs, a total of 111 injuries and 86 illnesses, during the IYOG, were reported, resulting in an incidence of 108.7 injuries and 84.2 illnesses per 1000 registered athletes, respectively. Injury frequency was highest in skiing in the halfpipe (44%) and snowboarding (halfpipe and slope style: 35%), followed by ski cross (17%), ice hockey (15%), alpine skiing (14%) and figure skating (12%), taking into account the respective number of participating athletes. Knee, pelvis, head, lower back and shoulders were the most common injury locations. About 60% of injuries occurred in competition and about 40% in training, respectively. In total, 32% of the injuries resulted in an absence from training or competition. With regard to illnesses, 11% of women and 6% of men suffered from an illness (RR=1.84 (95% CI 1.21 to 2.78), p=0.003). The respiratory system was affected most often (61%).

Conclusions

Eleven per cent of the athletes suffered from an injury and 9% from illnesses, during the IYOG. The presented data constitute the basis for future analyses of injury mechanisms and associated risk factors in Olympic Winter sports, which, in turn, will be essential to develop and implement effective preventive strategies for young elite winter-sport athletes.
Tri-axial high-resolution acceleration for oxygen uptake estimation: Validation of a multi-sensor device and a novel analysis method
Authors: Weippert Matthias , Stielow Jan , Kumar Mohit , Kreuzfeld Steffi , Rieger Annika , Stoll Regina
Published: November 2012

We validated a multi-sensor chest-strap against indirect calorimetry and further introduced the total-acceleration-variability (TAV) method for analyzing high-resolution accelerometer data. Linear regression models were developed to predict oxygen uptake from the TAV-processed multi-sensor data. Individual correlations between observed and TAV-predicted oxygen uptake (V̇O2) were strong (mean r = 0.94) and bias low (1.5 mL·min–1·kg–1, p < 0.01; 95% confidence interval: 8.7 mL·min–1·kg–1; –5.8 mL·min–1·kg–1); however, caution should be taken when a single-model value is used as a surrogate for V̇O2.
Molecular mechanisms of antimicrobial resistance in fecal Escherichia coli of healthy dogs after enrofloxacin or amoxicillin administration
Authors: Aly Sherine A. , Debavalya Nipattra , Suh Sang-Jin , Oryazabal Omar A. , Boothe Dawn M.
Published: November 2012

Escherichia coli respond to selective pressure of antimicrobial therapy by developing resistance through a variety of mechanisms. The purpose of this study was to characterize the genetic mechanisms of antimicrobial resistance in fecal E. coli after the routine use of 2 popular antimicrobials. Fourteen resistant E. coli isolates, representing predominant clones that emerged in healthy dogs’ feces after treatment with either amoxicillin (11 E. coli isolates) or enrofloxacin (3 E. coli isolates), were tested for mutations in DNA gyrase (gyrA and gyrB) and in topoisomerase IV (parC) and for the presence of β-lactamases (blaTEM, blaSHV, blaPSE-1 and blaCTX-M) and plasmid-mediated quinolone resistance (qnrA, qnrB, qnrS, aac(6′)-Ib, and qepA), by polymerase chain reaction. Escherichia coli isolates cultured following amoxicillin therapy only expressed single-drug resistance to β-lactams, while the isolates cultured from dogs receiving enrofloxacin therapy expressed multidrug resistance (MDR). The use of RND efflux pump inhibitors increased the susceptibility of the 3 MDR E. coli isolates to doxycycline, chloramphenicol, enrofloxacin, and ciprofloxacin, which indicates a role of the efflux pump in the acquisition of the MDR phenotype. Amplification and sequencing of AcrAB efflux pump regulators (soxR, soxS, marR, and acrR) revealed only the presence of a single mutation in soxS in the 3 MDR isolates.
Colour reconnections in Herwig++
Authors: Gieseke Stefan , Röhr Christian , Siódmok Andrzej
Published: November 2012

We describe the implementation details of the colour reconnection model in the event generator Herwig++. We study the impact on final-state observables in detail and confirm the model idea from colour preconfinement on the basis of studies within the cluster hadronization model. Moreover, we show that the description of minimum bias and underlying event data at the LHC is improved with this model and present results of a tune to available data.
RANK ONE CONNECTIONS ON ABELIAN VARIETIES, II
Authors: BISWAS INDRANIL , HURTUBISE JACQUES , RAINA A. K.
Published: November 2012

Given a holomorphic line bundle L on a compact complex torus A, there are two naturally associated holomorphic ΩA-torsors over A: one is constructed from the Atiyah exact sequence for L, and the other is constructed using the line bundle [Formula: see text], where α is the addition map on A × A, and p1 is the projection of A × A to the first factor. In [I. Biswas, J. Hurtvbise and A. K. Raina, Rank one connections on abelian varieties, Internat. J. Math.22 (2011) 1529–1543], it was shown that these two torsors are isomorphic. The aim here is to produce a canonical isomorphism between them through an explicit construction.
THEORETICAL OVERVIEW ON THE FLAVOR ISSUES OF MASSIVE NEUTRINOS
Authors: LUO SHU , XING ZHI-ZHONG
Published: November 2012

We present an overview on some basic properties of massive neutrinos and focus on their flavor issues, including the mass spectrum, flavor mixing pattern and CP violation. The lepton flavor structures are explored by taking into account of the observed value of the smallest neutrino mixing angle θ13. The impact of θ13 on the running behaviors of other flavor mixing parameters is discussed in some detail. The seesaw-induced enhancement of the electromagnetic dipole moments for three Majorana neutrinos is also discussed in a TeV seesaw scenario.
SPARSE-BASED AUDITORY MODEL FOR ROBUST SPEAKER RECOGNITION
Authors: YOU DATAO , HAN JIQING , ZHENG TIERAN , ZHENG GUIBIN
Published: November 2012

The mismatch between the training and the testing environments greatly degrades the performance of speaker recognition. Although many robust techniques have been proposed, speaker recognition in mismatch condition is still a challenge. To solve this problem, we propose a sparse-based auditory model as the front-end of speaker recognition by simulating auditory processing of speech signal. To this end, we introduce narrow-band filter-bank instead of the widely used wide-band filter-bank to simulate the basilar membrane filter-bank, use sparse representation as the approximation of basilar membrane coding strategy, and incorporate the frequency selectivity enhance mechanism between tectorial membrane and basilar membrane by practical engineering approximation. Compared with the standard Mel-frequency cepstral coefficient approach, our preliminary experimental results indicate that the sparse-based auditory model consistently improve the robustness of speaker recognition in mismatched condition.
INTUITIONISTIC FUZZY REASONING FOR MULTIPLE TWO-CLASS CLASSIFIERS FUSION
Authors: WANG HAI , QIAN GANG , FENG XIANGQIAN
Published: November 2012

Combining outputs of a pool of individual classifiers appropriately, as a hot research topic of pattern classification, can generate statistically significant increase in classification performances. During the last decades, several fusion algorithms were presented, but few of those focus on two-class classification which possesses wide application area such as sentiment classification, cancer differentiation and so on. Thus the main purpose of this paper is to develop a highly effective fusion algorithm, i.e. intuitionistic fuzzy reasoning fusion algorithm, to increase the performance of a multiple two-class classifiers system. The outputs of component classifiers are represented by a set of intuitionistic fuzzy values at first and the fusion process is interpreted as aggregation of intuitionistic fuzzy information. The proposed algorithm includes three versions using the intuitionistic fuzzy arithmetic average operator, intuitionistic fuzzy weighted average operator and induced intuitionistic fuzzy ordered weighted average aggregation operator, respectively. The proposed fusion algorithm can combine both evidences of the hypothesis that a test pattern belongs to a class and evidences of the hypothesis that the test pattern does not belong to the class at the same time. We compare the versions of our algorithm with four other fusion techniques on five open-access datasets. The proposed algorithm exhibits good predictive abilities, compared to the best individual classifiers and other comparable fusion techniques. Further, the experiments show some interesting results about measuring and weighting component classifiers.
A READOUT SOLUTION FOR MEMS SENSORS
Authors: SUPON TAREQ MUHAMMAD , THANGARAJAH KRISHNAMOHAN , RASHIDZADEH RASHID , AHMADI MAJID
Published: November 2012

A new readout circuit for MEMS devices is presented in this paper. A Phase Locked Loop (PLL) has been utilized to convert variations of MEM capacitance to time domain signals. The proposed scheme presents a robust performance against process, power supply and temperature variations due to inherent feedback of PLL systems. Simulation results in Cadence environment using TSMC CMOS 65-nm technology indicate that a measurement resolution of 73 aF can be achieved.
TRICRITICAL QUANTUM POINT AND INFLATIONARY COSMOLOGY
Authors: CROWELL LAWRENCE B.
Published: November 2012

The holographic protection due to inflationary cosmology is a consequence of a quantum tricritical point. In this scenario a closed spacetime solution transitions into an inflationary de Sitter spacetime. Saturation of the holographic entropy bound is prevented by the phase change in the topology of the early universe.
LOCALIZATION PROBLEM IN THE 5D STANDING WAVE BRANEWORLD
Authors: GOGBERASHVILI MERAB , MIDODASHVILI PAVLE , MIDODASHVILI LEVAN
Published: November 2012

We investigate the problem of pure gravitational localization of matter fields within the 5D standing wave braneworld generated by gravity coupled to a phantom-like scalar field. We show that in the case of increasing warp factor there exist normalizable zero modes of spin-0, -1/2, -1 and -2 fields on the brane.
OBSERVATIONAL EVIDENCES FOR SPINNING BLACK HOLES: A PROOF OF GENERAL RELATIVITY FOR SPACETIME AROUND ROTATING BLACK HOLES
Authors: MUKHOPADHYAY BANIBRATA , BHATTACHARYA DEBBIJOY , SREEKUMAR P.
Published: November 2012

Since it was theorized by Kerr in 1963, determining the spin of black holes from observed data was paid very little attention until few years back. The main reasons behind this were the unavailability of adequate data and the lack of appropriate techniques. In this paper, we explore determining/predicting the spin of several black holes in X-ray binaries (XRBs) and in the center of galaxies, using X-ray and gamma-ray satellite data. For X-ray binaries, in order to explain observed quasi-periodic oscillations (QPOs), our model predicts the spin parameter of underlying black holes. On the other hand, the nature of spin parameters of black holes in BL Lacs and flat spectrum radio quasars (FSRQs) is predicted by studying the total luminosities of systems based on Fermi γ-ray data. All sources considered here exhibit characteristics of spinning black holes, which verifies natural existence of the Kerr metric.
ASYMPTOTIC DYNAMICS OF A CLASS OF COUPLED OSCILLATORS DRIVEN BY WHITE NOISES
Authors: SHEN WENXIAN , SHEN ZHONGWEI , ZHOU SHENGFAN
Published: November 2012

This paper is devoted to the study of the asymptotic dynamics of a class of coupled second order oscillators driven by white noises. It is shown that any system of such coupled oscillators with positive damping and coupling coefficients possesses a global random attractor. Moreover, when the damping and the coupling coefficients are sufficiently large, the global random attractor is a one-dimensional random horizontal curve regardless of the strength of the noises, and the system has a rotation number, which implies that the oscillators in the system tend to oscillate with the same frequency eventually and therefore the so-called frequency locking is successful. The results obtained in this paper generalize many existing results on the asymptotic dynamics for a single second order noisy oscillator to systems of coupled second order noisy oscillators. They show that coupled damped second order oscillators with large damping have similar asymptotic dynamics as the limiting coupled first order oscillators as the damping goes to infinite and also that coupled damped second order oscillators have similar asymptotic dynamics as their proper space continuous counterparts, which are of great practical importance.
FABRICATION OF LARGE-AREA SILICON NANOWIRE ARRAYS FOR SOLAR CELLS
Authors: LAI WUXING , XU GUOQIANG , ZHANG WEI , SHI TIELIN
Published: November 2012

In this paper, a simple, low-cost and efficient method was adopted to fabricate large-area Si nanowire ( SiNW ) arrays by inserting the p-type (100) silicon wafer into aqueous HF + AgNO3 solution for a certain time at room temperature. Surface of the silicon wafer with high aspect ratio SiNW shows the characteristics of low-reflection as low as 5% in the 450–800 nm wavelength range, especially less than 1% after etching for 60 min. The surface also exhibits super-hydrophobicity with water contact angle up to 150°. We investigated the relationship between the etching duration and aspect ratio of the SiNW systematically and demonstrated that the aspect ratio of the SiNW can be controlled. The antireflection surface shows a potential implication in increasing the conversation efficiency for solar cells, and the self-cleaning properties will further enhance the resistance to environment conditions for a long-life work.
CATALYSIS OF CUPROUS OXIDE TOWARD HYDROGEN PEROXIDE ELECTROREDUCTION
Authors: SUN LIMEI , CHEN JING
Published: November 2012

The cuprous oxide nanoparticles were prepared with glucose as reducing agent by a wet-chemical method. The composition and structure of the catalysts were characterized with XRD and SEM analysis. The catalytic activity and stability of the catalyst for the H2O2 reduction were studied using the curves of cyclic voltammetry and chronoamperometry. The results showed that the crystal structure of the synthesized Cu2O was the pure cubic phase and the crystallite size was about 19.5 nm. The Cu2O powder was spherical and the average diameter of the spheres is about 1.0 μm. The Cu2O nanoparticles were active for H2O2 electroreduction and the current density was about 30 mA cm-2 at E = -0.4 V .
CARBON NANOTUBES AND NANO-Ce–Zr OXIDES SUPPORTED H3PW12O40 FOR EFFECTIVE ADSORPTION–DECOMPOSITION OF NOx
Authors: CHENG LIN , WANG RUI
Published: November 2012

Surface-modified carbon nanotubes (CNTs) and nano- Ce–Zr mixed oxides (CZO) were prepared and employed initially as supports of H3PW12O40 (HPW) for NO x adsorption–decomposition. Both CNTs and nano-CZO are favorable supports for HPW. After loading with HPW, the NO x adsorption efficiency increases, especially for HPW/CZO in which the highest adsorption efficiency can achieve 98% at the HPW loading of 70%, much higher than that of single HPW. NO x adsorption efficiency can be influenced considerably by catalyst preparing conditions, in particularly, ethyl alcohol is superior to water as solvent for HPW loading onto CNTs; the –OH containing CNTs shows better promotion effect on the adsorption of NO x than that containing –COOH when using absolute ethyl alcohol as solvent; mechanical grinding method is superior to incipient impregnation method in loading HPW onto the support of CZO. For both catalysts of HPW/CNTs and HPW/CZO, with the increase of HPW loading, the NO x adsorption efficiency tends to reach a peak value before dropping down. Heated from 150°C to 450°C at a rate of 50°C/min, the adsorbed NO was found to decompose into N2 , O2 and N2O , and yields of N2 being 21.8% and 27.3%, respectively for HPW/CNTs and HPW/CZO were obtained.
SELF-ASSEMBLY FABRICATION OF GRAPHENE-BASED MATERIALS WITH OPTICAL–ELECTRONIC, TRANSIENT OPTICAL AND ELECTROCHEMICAL PROPERTIES
Authors: ZHU JIAYI , HE JUNHUI
Published: November 2012

Directed self-assembly of nano or microsized materials as building blocks is a very exciting research topic to construct large-scale but still uniform 2D or 3D architectures. Graphene shows great potential as an advanced building block for fabricating varied graphene-based functional films or architectures together with other metal, metal oxide and semiconductor nanomaterials. In our work, we demonstrated an approach to fabrication of flexible, transparent conductive thin films via layer-by-layer (LbL) assembly of oppositely charged reduced graphene oxides (RGOs). The graphene thin films showed remarkable optical–electronic properties. Inspired by this, we further fabricated transparent conductive hybrid thin film via LbL assembly of oppositely charged RGO nanosheets and Pt nanoparticles. The graphene– Pt hybrid thin film showed transient optical property as well as appropriate conductive and wetting properties. Moreover, we demonstrated graphene wrapped- MnO2 (GW- MnO2 ) nanocomposites by self-assembly of honeycomb MnO2 nanospheres and graphene sheets via an electrostatic co-precipitation method. The hybrid materials had a good electrochemical performance.
INDICATION OF CESIUM ADSORPTION INTO ANGSTROM-SCALE OPEN SPACES IN SAPONITE CLAY MINERAL
Authors: NUMATA KAZUOMI , SATO KIMINORI , FUJIMOTO KOICHIRO
Published: November 2012

Adsorption behavior of cesium (Cs) into angstrom-scale open spaces for the saponite clay mineral is investigated by making use of positronium (Ps) annihilation spectroscopy together with thermogravimetry and differential thermal analysis (TG–DTA). Ps annihilation spectroscopy reveals two kinds of open spaces with their sizes of ~ 3 Å and ~ 10 Å, respectively, after baking at 423 K for 8 h under the vacuum condition at ~ 10-5 Torr. The large open space is found to survive for the Cs -type saponite due to less hydration of the Cs cations even after the exposure to the air for 200 h. It is thus inferred that Cs is locally adsorbed in the angstrom-scale open spaces in the saponite clay minerals.
MICROSTRUCTURAL PROPERTIES OF NC-Si/SiO2 FILMS IN SITU GROWN BY REACTIVE MAGNETRON CO-SPUTTERING
Authors: LU WANBING , GUO SHAOGANG , WANG JIANTAO , LI YUN , WANG XINZHAN , YU GENGXI , FAN SHANSHAN , FU GUANGSHENG
Published: November 2012

Nanocrystalline silicon embedded in silicon oxide (nc- Si/SiO2 ) films have been in situ grown at a low substrate temperature of 300°C by reactive magnetron co-sputtering of Si and SiO2 targets in a mixed Ar/H2 discharge. The influences of H2 flow rate (F H ) on the microstructural properties of the deposited nc- Si/SiO2 films were investigated. The results of XRD and the deposition rate of nc- Si/SiO2 films show that the introduction of H2 contributes to the growth of nc- Si grains in silicon oxide matrix. With further increasing F H , the average size of nc- Si grains increases and the deposition rate of nc- Si/SiO2 films decreases gradually. Fourier transform infrared spectra analyses reveal that introduction of hydrogen contributes to the phase separation of nc- Si and SiO x in the deposited films. Moreover, the Si–O 4-n Si n(n = 0, 1) concentration of the deposited nc- Si/SiO2 films reduces with the increase of F H , while that of Si – O 4-n Si n(n = 2, 3) concentration increases. These results can be explained by that active hydrogen atoms increase the probability of reducing oxygen from precursor in the plasma and prompting oxygen desorption from the growing surface. This low-temperature procedure for preparing nc- Si/SiO2 films opens up the possibility of fabricating the silicon-based thin-film solar cells onto low-cost glass substrates using nc- Si/SiO2 films.
CONTROLLED RELEASE OF IMIDACLOPRID FROM POLY (STYRENE–DIACETONE CRYLAMIDE)-BASED NANOFORMULATION
Authors: QIAN KUN , GUO YANZHEN , HE LIN
Published: November 2012

Imidacloprid is a neonicotinoids insecticide, which is important for the cash crops such as tomato, rape and so on. The conventional formulation does not only increase the loss of pesticide but also leads to environmental pollution. Controlled-release formulations of pesticide are highly desirable not only for attaining the most effective utilization of the pesticide, but also for reducing environmental pollution. Pesticide imidacloprid was incorporated in poly (styrene–diacetone crylamide)-based formulation to obtain controlled release properties, and the imidacloprid nanocontrolled release formulation was characterized by infrared (IR) and field emission scanning electron microscope (FESEM). Factors related to loading efficiency, swelling and release behaviors of the formulation were investigated. It showed that the loading efficiency could reach about 40% (w/w). The values for the diffusion exponent "n" were in the range of 0.31–0.58, which indicated that the release of imidacloprid was diffusion-controlled. The time taken for 50% of the active ingredient to be released into water, T50, was also calculated for the comparison of formulations in different conditions. The results showed that the formulation with higher temperature and more diacetone crylamide had lower value of T50, which means a quicker release of the active ingredient. This study highlighted some pieces of evidence that improved pesticide incorporation and slower release were linked to potential interactions between the pesticide and the polymer.
SYNTHESIS OF NANOCRYSTALLINE CdS QUANTUM DOTS VIA PARAFFIN LIQUID AS SOLVENT AND OLEIC ACID AS THE REACTING MEDIA
Authors: LI WENJIANG , WANG MINGRUI , XIE FEI , ZHU SHA , ZHAO YUE
Published: November 2012

Fluorescent semiconductor nanocrystals have been widely used as fluorescent materials in chemical sensors, biotechnology, medical diagnostics, biological imaging and many other fields. Compared to the conventional organic fluorophores, the inorganic quantum dots (QDs) have many advantages, including broad absorption spectra, narrow emission spectra, good photostability and long fluorescent lifetime after excitation. Here, the high quality CdS QDs were synthesized directly from sulfur and CdO using the paraffin liquid as solvent and the oleic acid as the reacting media. The synthesized CdS QDs with a zinc blende (cubic) crystal structure were proved by X-ray diffraction. HRTEM observation revealed that the CdS QDs were uniform and the average grain size was about 4 nm. The optical properties of the CdS QDs were characterized by using photoluminescence (PL) spectrophotometer and Ultraviolet-visible (UV-Vis) absorption spectrophotometer. The formation mechanism of CdS QDs in the paraffin liquid and oleic acid system was proposed.
HIGH DISPERSION BARIUM SULFATE NANOPARTICLES PREPARED WITH DODECYL BENZENE SULFONIC ACID
Authors: LI YING , WANG XUANJUN , CUI YIBIN , MA WENXIN , GUO HENG
Published: November 2012

Production of nanoparticles by precipitation is a relatively simple process but the control of product particle size distribution is difficult. In this paper, nanosize barium sulfate ( BaSO 4) particles are prepared with dodecyl benzene sulfonic acid (DBSA) in ethanol–water reaction system at room temperature. The BaSO4 nanoparticles are characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), powder X-ray diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR) and thermo gravimetric analysis (TGA), respectively. The results indicated that the average diameter of spherical BaSO4 is about 46 nm modified with 5 wt.% DBSA, which have good dispersion in the presence of a certain concentration NH3 ⋅ H2O . It suggests that the high dispersion is attributed to presence of a thin layer of barium alkyl sulfate, which is formed and coated onto the surface of BaSO4 particles during the reaction process. The thin films on the surface of the BaSO4 effectively modified the surface and properties, which also control the particle size and morphology.
A CHITOSAN TEMPLATED SYNTHESIS OF BIMODAL POROUS SILICA
Authors: JIANG NANZHE , LI CHENGBIN , CHEN SHIJUAN , LIU GUANGXUE , MENG WAN
Published: November 2012

Biopolymer chitosan templated bimodal porous silica materials with uniform macroporosity and narrowed mesopore size distribution were synthesized via fast precipitation of chitosan–silica hybrid composites (Chi/ SiO2 ). Clear Chi/ SiO2 solutions containing the biopolymer chitosan and siloxane-based inorganic network were prepared by hydrolysis of sodium metasilicate in the presence of biopolymer chitosan. The relative amount of chitosan in as-made Chi/ SiO2 was analyzed by thermogravimetric analysis (TGA). Chi/ SiO2 was calcined at 600°C for 5 h in the presence air to remove chitosan, and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM) and N2 adsorption–desorption isotherms. These porous silica products had high specific surface area of 500–550 m2/g, narrow pore size distribution and also bicontinuous macropore structure.
RESEARCH ON DISCHARGE CIRCUIT OF ELECTRO-HYDRAULIC POWER IMPULSE WATER JETS
Authors: WANG ZHAOHUI , GAO QUANJIE , WANG WEI , LIAO ZHENFANG
Published: November 2012

Electro-hydraulic power impulse water jets can convert the shock wave generated in the liquid by discharging into mechanical energy, and it has been widely used in material forming, surface cleaning, pipeline dirt cleaning and ore breaking process. Compared with the traditional high pressure water jets, the energy utilization of electro-hydraulic power impulse water jets is up to 80% while the water consumption is reduced by 40–55%. This paper has taken electro-hydraulic power impulse water jets as the research object, employed obtaining the maximum pressure of compression impulse matrix surface as the research goal, studied in depth the equivalent discharge circuit, characteristic equation and the relationship between the electrical parameters of the electro-hydraulic power impulse discharge circuit and built the calculation method of the voltage, the inductance, the capacitance and the electrode spacing parameter of electro-hydraulic power impulse water jets discharge circuit. So, it will provide important theoretical basis for further studies of electro-hydraulic power impulse technology and the existing water jets device.