bluuebunny/crossref_metadata_2025 huggingface dataset:
Partial Cauchy Data for General Second Order Elliptic Operators in Two Dimensions
Authors: Imanuvilov Oleg Yu. , Uhlmann Gunther , Yamamoto Masahiro
Published: November 2012

We consider the inverse problem of determining the coefficients of a general second order elliptic operator in two dimensions by measuring the corresponding Cauchy data on an arbitrary open subset of the boundary. We show that one can determine the coefficients of the operator up to natural limitations such as conformal invariance, gauge transformations and diffeomorphism invariance. We use the main result to prove that the curl of the magnetic field and the electric potential are uniquely determined by measuring partial Cauchy data associated to the magnetic Schrödinger equation on an arbitrary open subset of the boundary. We also show that any two of the three coefficients of a second order elliptic operator whose principal part is the Laplacian, are uniquely determined by their partial Cauchy data.
Synthesis of furo[3,2-c]coumarin from the reaction of 3-halochromone and 2-aminochromone; 2-aminochromone as a masked 4-hydroxycoumarin
Authors: Biswas Pritam , Ghosh Jaydip , Sarkar Tapas , Maiti Sourav , Bandyopadhyaya Chandrakanta
Published: November 2012

Synthesis of 2-(2-hydroxybenzoyl)-4 H-furo[3,2- c]chromen-4-one has been accomplished by the reaction of 3-halochromone with 2-aminochromone. In this reaction, 2-aminochromone acts as a masked 4-hydroxycoumarin.
Preparation of a pH-Sensitive Polystyrene Fluorescent Microsphere based on a Cyanine Dye
Authors: Yu Liang , Wang Qiuling , Li Tingting , Chen Ligong
Published: November 2012

A novel pH-sensitive near-IR (NIR) fluorescent dye was synthesised and utilised in the preparation of fluorescent polystyrene microspheres. Their photochemical properties, as well as the pH-dependent optical properties were investigated and showed high sensitivity to changes of pH in the range of 3.3–8.1. The fluorescence became stronger with the increase in pH. Importantly, the microspheres were able to work in aqueous media, which is highly valuable for use in biological applications.
Polystyrene-Immobilised Phenanthroline Palladium(II) Complex: A Highly Efficient and Recyclable Catalyst for Oxidative Heck Reactions
Authors: Wang Pingping , Zhang Jiatao , Cai Mingzhong
Published: November 2012

Oxidative Heck coupling reactions of arylboronic acids with olefins were carried out in the presence of the polystyrene-immobilised phenanthroline palladium(II) complex using air as a co-oxidant to afford the Heck coupling products in high yields under base-free conditions. This heterogeneous palladium catalyst can be recovered by simple filtration and used for several times without loss of activity or selectivity.
Extent of Nucleophilic Participation in the Solvolyses of Alkyl Chloromethyl Ethers and Sulfides
Authors: Park Byoung-Chun , Kevill Dennis N.
Published: November 2012

The specific rates of solvolysis have been determined for chloromethyl ethyl ether (3) and chloromethyl octyl ether (4) at −10.0 °C and for chloromethyl methyl sulfide (5) at 25.0 °C in a variety of pure and binary solvents. These values were used for a correlation analysis treatment using the extended Grunwald–Winstein equation incorporating literature values for solvent nucleophilicity ( NT) and solvent ionising power ( YCl). Appreciable values were found for the sensitivities towards changes in both NT and YCl values. Using a literature specific rate of hydrolysis at 25.0 °C for fluoromethyl methyl ether (2), the required value for chloromethyl methyl ether (1) was obtained from use of NT and YCl values and the sensitivities for 3 to changes in their values, to adjust an experimental specific rate value for 1 in 100% ethanol to the corresponding value in 100% water. In this way, an estimated kCl/ kF of 1.2 × 105 was obtained, essentially identical to values for the solvolyses of tert-butyl halides. A unimolecular mechanism for the solvolyses, with appreciable nucleophilic solvation of the developing carbocation, is proposed. Electronic supplementary information provides, for several solvents, specific rates of solvolysis for 3, 4, and 5 at additional temperatures and the calculated activation parameters.
A New Phenylpentanamine Alkaloid Produced by an Endophyte Bacillus Subtilis Isolated from Angelica sinensis
Authors: Yang Nian-Yun , Jiang Shu , Shang Er-Xin , Tang Yu-Ping , Duan Jin-Ao
Published: November 2012

Investigation of an endophyte Bacillus subtilis isolated from Angelica sinensis, has led to the isolation of a new phenylpentanamine alkaloid, 5-phenylpentan-1,3,4-triamine. Its structure was elucidated by chemical and spectroscopic means. This is the first report of the occurrence of a natural phenylpentanamine alkaloid.
Formation of a New 1D Coordination Polymer by in situ Ligand Reaction of 2,4,6-tris(pyrazol-1-yl)-1,3,5-s-triazine
Authors: Cao Qiang
Published: November 2012

Solvothermal reactions of Zn(NO3)2·6H2O, 1,4-benzenedicarboxylic acid (H2BDC) and 2,4,6-tris(pyrazol-1-yl)-1,3,5-s-triazine, yielded a new coordination polymer [Zn(BDC)(pz)·H2O]n (pz= pyrazole). The in situ methanolysis reaction of 2,4,6-tris(pyrazol-1-yl)-1,3,5-s-triazine with pyrazole and 2,4,6-trismethoxy-1,3,5-triazine was confirmed by their single-crystal structures. [Zn(BDC)(pz)·H2O]n was characterised by elemental analysis, IR, powder X-ray diffraction, photoluminescence and thermogravimetric analyses.
Synthesis and Characterisation of New Metallophthalocyanines Containing Four 12-Membered Diazadithia-Macrocyclic Moieties
Authors: Kaya Elif Çelenk , Kantekin Halit , Kaya Afşin Ahmet , Dakoğlu Asuman , Öksüz Sümeyra , Şişik Hanife
Published: November 2012

Tetrasubstituted zinc, cobalt, nickel, copper and lead phthalocyanines bearing four 12-membered diazadithia macrocyclic moieties on peripheral positions have been synthesised by cyclotetramerisation reaction of 1,10-ditosyl-1,2,3,5,6,8,9,10-octahydrobenzo[h][1,4,7,10]dithiadiazacyclododecine-12,13-dicarbonitrile and corresponding anhydrous metal salts under microwave irradiation. The thermal stabilities of the phthalocyanine compounds have determined by thermogravimetric analysis.
Synthesis and Antimicrobial Activity of New Phthalocyanine Complexes and Electrochemical and Spectroelectrochemical Behaviour of Cobaltphthalocyanine
Authors: Kaya Elif Çelenk , Karadeniz Hülya , Koca Atif , Kahriman Nuran , Sökmen Atalay
Published: November 2012

A novel phthalocyanine bearing oxygen donor atoms on the peripheral positions has been synthesised by cyclotetramerisation of ( E)-4-(4-cinnamoylphenoxy) phthalonitrile and its nickel, zinc, cobalt, copper and lead derivatives prepared. The thermal stabilities of the phthalocyanine compounds have been determined and their possible biological activities (antibacterial, anticandidal and antifungal) studied. The effects of substituent on the electrochemical and in situ spectroelectrochemical behaviour of cobaltphthalocyanine have been investigated and an in situ electrocolorimetric method was applied to investigate the colour of the electrogenerated anionic and cationic forms of the complex.
Hydrazonoyl Halides as Precursors for Synthesis of Novel Bioactive Thiazole and Formazan Derivatives
Authors: Farghaly Thoraya A. , Abbas Eman M.H.
Published: November 2012

A new series of substituted 4-methyl-5-(arylazo)-2-[ N‘-(6,7,8,9-tetrahydro-benzocyclohepten-5-ylidene)-hydrazino]-thiazoles and 5-(arylhydrazono)-2-[ N‘-(6,7,8,9-tetrahydro-benzocyclohepten-5-ylidene)-hydrazino]-thiazol-4-one were prepared by reaction of hydrazonoyl chlorides with a thiosemicarbazone derivative. The tautomeric structures of the products were studied using electronic absorption and NMR spectroscopy. The site-selectivities of the reactions of hydrazonoyl halides with benzocyclohepten-5-one hydrazone were also investigated. In addition, the antimicrobial activity of some of the products was evaluated. Many derivatives have promising activities against antibacterial and antifungal species.
Fe(II)-Catalysed Homocoupling of Arenediazonium Tetrafluoroborates
Authors: Zhou Jiatian , Yu Shuangshuang , Cheng Kai , Qi Chenze
Published: November 2012

An efficient procedure for the synthesis of biaryls was catalysed by Fe(acac)2 and zinc powder in carbon tetrachloride solution at 60 °C using arenediazonium salts is reported. Symmetrical bi-aryl molecules with various substituents on the phenyl ring (methyl, trifluoromethyl, halogen, nitro, methoxyl) were synthesised in good yields in a short time under air. Zinc powder was used as reductant in the reaction to facilitate the regeneration of the iron(II) catalyst.
A Convenient and Efficient Synthesis of 2,6-Dihydroxynaphthalene
Authors: Cui Jia-hua , Li Shao-shun
Published: November 2012

A convenient synthesis of 2,6-dihydroxynaphthalene from 6-bromo-2-naphthol has been achieved with high overall yield (52%) and good purity (95.7%) based on the conversion of 6-(methoxymethoxy)-2-naphthaldehyde to 6-(methoxymethoxy)-2-naphthol formate by a Baeyer–Villiger oxidation-rearrangement. Compared with the reported methods, the reaction conditions are milder and the work-up of each step is much simpler. Moreover, 6-bromo-2-naphthol as the starting material for the synthesis is readily available.
Ni(II) and Cu(II) Complexes of Pyridyl-Pyrazole Ligands: Syntheses, Crystal Structures and Influence of Metal Ion
Authors: Du Jian-Long , Zhu Xiao-Long , Yang Xiao-Yan , Shen Tian-Li , Li Li-Jun
Published: November 2012

The ligand 3-(2-pyridyl)pyrazol-1-yl acetic acid (HL) has been prepared and the complexes [Ni(L)(N3)] n and [Cu(L‘)2(H2O)2] n [HL‘ = 3-(2-pyridyl)pyrazole] have been synthesised by reaction of HL and NaN3 with NiCl2·6H2O and CuCl2·2H2O under hydrothermal condition. Single-crystal X-ray diffraction analysis shows that [Ni(L)(N3)] n possesses a 1D infinite chain structure, which further forms a 2D supramolecular framework connected by π···π weak interactions, and [Cu(L‘)2(H2O)2] n is linked to form a 1D chain by π···π weak interactions, then to a 2D supramolecular structure by weak C–H···O interactions.
Asymmetric Synthesis of both (R)-and (S)-arundic acid
Authors: Lu Cuifen , Zhang Longduo , Su Hang , Yang Guichun , Chen Zuxing
Published: November 2012

The asymmetric synthesis of both ( R)-and ( S)-arundic acid has been achieved via the key step of a stereoselective alkylation reaction using non-cross-linked polystyrene (NCPS) supported (4 R)- and (4 S)-2-phenylimino-2-oxazolidine as chiral auxiliaries. This method is efficient (both enantiomers were obtained in 99% ee and 60% overall yield) and the chiral auxiliaries can be recovered quantitatively by simple filtration.
Male and female shame: a corpus-based study of emotion
Authors: Norberg Cathrine
Published: November 2012

In this study, I investigate the representation of the emotion terms shame, ashamed and shameless in relation to women and men in late twentieth-century British English. The study is based on analyses of examples of shame retrieved from the British National Corpus with the specific aim to study in what contexts men and women express shame or are associated with it, and evaluate whether the emotion is represented as negative or positive.

I present two general models of shame, where the first model concentrates on a negative connection between shame and pain, exposure and embodiment, and the second model describes shame as a necessary ingredient of social life that makes people recommit to socially sanctioned behaviour and values. Most examples of women's shame in the material correspond to the description given in the first model, whereas the majority of the examples of men's shame correspond with the second. The two models illustrate how shame functions to preserve hierarchical gender structures.
Coral: Corpus Access in Controlled Language
Authors: Kuhn Tobias , Höfler Stefan
Published: November 2012

In this paper, we present Coral, an interface in which complex corpus queries can be expressed in a controlled subset of natural English. With the help of a predictive editor, users can compose queries and submit them to the Coral system, which then automatically translates them into formal AQL statements. We give an overview of the controlled natural language developed for Coral and describe the functionalities of the predictive editor provided for it. We also report on a user experiment in which the system was evaluated. The results show that, with Coral, corpora of annotated texts can be queried more easily and more quickly than with the existing ANNIS interface. Our system demonstrates that complex corpora can be accessed without the need to learn a complicated, formal query language.
Power Management System for Load Banks Supplied by Pitch Controlled Wind Turbine System
Authors: Merabet Adel , Keeble Raquel , Rajasekaran Vigneshwaran , Beguenane Rachid , Ibrahim Hussein , Thongam Jogendra
Published: November 2012

An automatic power management system, to monitor the distribution of power to a set of load banks, is presented in this paper. The required power is generated from a laboratory-size pitch-controlled wind turbine experimental workstation. The management system is a sequence of logic expressions, based on the generated power, a profile of the banks’ states provided by the supervisor and the banks’ priorities, to obtain an optimal behavior of the system and to ensure the load requirement. A modified PI pitch angle control is proposed to regulate the generated power for tracking the power reference in order to maintain a consistent brilliance of the load’s LEDs, to reduce the activity of the pitch actuator and to deal with fluctuation problems. Experimental results are provided to show the effectiveness of the proposed automatic power management system for load banks supplied by a pitch controlled wind turbine.
Short-Run and Long-Run Elasticities of Diesel Demand in Korea
Authors: Lim Kyoung-Min , Kim Myunghwan , Kim Chang , Yoo Seung-Hoon
Published: November 2012

This paper investigates the demand function for diesel in Korea covering the period 1986–2011. The short-run and long-run elasticities of diesel demand with respect to price and income are empirically examined using a co-integration and error-correction model. The short-run and long-run price elasticities are estimated to be −0.357 and −0.547, respectively. The short-run and long-run income elasticities are computed to be 1.589 and 1.478, respectively. Thus, diesel demand is relatively inelastic to price change and elastic to income change in both the short-run and long-run. Therefore, a demand-side management through raising the price of diesel will be ineffective and tightening the regulation of using diesel more efficiently appears to be more effective in Korea. The demand for diesel is expected to continuously increase as the economy grows.
Novel Microsatellite Markers of Meretrix petechialis and Cross-species Amplification in Related Taxa (Bivalvia: Veneroida)
Authors: Kang Jung-Ha , Kim Byeng-Hak , Park Jung-Youn , Lee Jung-Mi , Jeong Ji-Eun , Lee Jun-Sang , Ko Hyun-Sook , Lee Yong-Seok
Published: November 2012

The Asian hard clam, Meretrix petechialis, is an economically important bivalve, but its catch and population sizes are decreasing rapidly, owing to many factors, including large-scale reclamation of its natural habitat on the western coast of the Korean peninsula. Attempts to restore the resources and production of this species require genetic structure and diversity information. In this study, we developed 15 microsatellite markers from a partial genomic library enriched in GT repeats. Nine of these markers were polymorphic, with an average allele number of six, and six were monomorphic in 95 tested individuals. No linkage disequilibrium was found between any pair of loci (p > 0.05), and deviations from the Hardy–Weinberg equilibrium (HWE) test showing excess of heterozygotes was observed in only one of nine loci. In addition, no null alleles or genetic differentiation between two tested populations were detected. A cross-species amplification in 12 species of four families resulted in two M. petechialis-specific loci and three possible universal markers. This information will be useful in the future development of high-quality artificial seedlings and sustainable resource management.
Differential Expression Profile of MicroRNAs during Differentiation of Cardiomyocytes Exposed to Polychlorinated Biphenyls
Authors: Zhu Chun , Yu Zhang-Bin , Zhu Jin-Gai , Hu Xiao-Shan , Chen Yu-Lin , Qiu Yu-Fang , Xu Zheng-Feng , Qian Lin-Mei , Han Shu-Ping
Published: November 2012

Exposure to persistent environmental pollutants, such as polychlorinated biphenyls (PCBs), is a risk factor for the development of congenital heart defects. MicroRNAs (miRNAs) have been shown to be involved in cardiac development. The objective of this study was to investigate changes in miRNA expression profiles during the differentiation of cardiomyocytes exposed to PCBs. For that purpose, PCBs (Aroclor 1254) at a concentration of 2.5 μmol/L were added on day 0 of differentiation of P19 mouse embryonal carcinoma cells into cardiac myocytes. The relative expression of miRNA genes was determined by miRNA microarray and real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR) analyses. The microarray results revealed that 45 miRNAs, of which 14 were upregulated and 31 were downregulated, were differentially expressed in P19 cells treated with PCBs compared with control cells. The miRNA expression data was validated with real-time RT-PCR. The expression of certain potential target genes (Wnt1) was found to be reduced in P19 cells treated with PCBs, whereas the expression of other potential predicted target genes (GSK3β) was increased. Our results demonstrate a critical role of miRNAs in mediating the effect of PCBs during the differentiation of P19 cells into cardiac myocytes.
Identification and Characterization of the Actin-Binding Motif of Phostensin
Authors: Wang Tzu-Fan , Lai Ning-Sheng , Huang Kuang-Yung , Huang Hsien-Lu , Lu Ming-Chi , Lin Yu-Shan , Chen Chun-Yu , Liu Su-Qin , Lin Ta-Hsien , Huang Hsien-Bin
Published: November 2012

Phostensin, a protein phosphatase 1 F-actin cytoskeleton-targeting subunit encoded by KIAA1949, consists of 165 amino acids and caps the pointed ends of actin filaments. Sequence alignment analyses suggest that the C-terminal region of phostensin, spanning residues 129 to 155, contains a consensus actin-binding motif. Here, we have verified the existence of an actin-binding motif in the C-terminal domain of phostensin using colocalization, F-actin co-sedimentation and single filament binding assays. Our data indicate that the N-terminal region of phostensin (1–129) cannot bind to actin filaments and cannot retard the pointed end elongation of gelsolin-actin seeds. Furthermore, the C-terminal region of phostensin (125–165) multiply bind to the sides of actin filaments and lacks the ability to block the pointed end elongation, suggesting that the actin-binding motif is located in the C-terminal region of the phostensin. Further analyses indicate that phostensin binding to the pointed end of actin filament requires N-terminal residues 35 to 51. These results suggest that phostensin might fold into a rigid structure, allowing the N-terminus to sterically hinder the binding of C-terminus to the sides of actin filament, thus rendering phostensin binding to the pointed ends of actin filaments.
Asymmetric Dimethyarginine as Marker and Mediator in Ischemic Stroke
Authors: Chen Shufen , Li Na , Deb-Chatterji Milani , Dong Qiang , Kielstein Jan , Weissenborn Karin , Worthmann Hans
Published: November 2012

Asymmetric dimethylarginine (ADMA), an endogenous nitric oxide synthase (NOS) inhibitor, is known as mediator of endothelial cell dysfunction and atherosclerosis. Circulating ADMA levels are correlated with cardiovascular risk factors such as hypercholesterolemia, arterial hypertension, diabetes mellitus, hyperhomocysteinemia, age and smoking. Accordingly, clinical studies found evidence that increased ADMA levels are associated with a higher risk of cerebrovascular events. After the acute event of ischemic stroke, levels of ADMA and its analog symmetric dimethylarginine (SDMA) are elevated through augmentation of protein methylation and oxidative stress. Furthermore, cleavage of ADMA through dimethylarginine dimethylaminohydrolases (DDAHs) is reduced. This increase of dimethylarginines might be predictive for adverse clinical outcome. However, the definite role of ADMA after acute ischemic stroke still needs to be clarified. On the one hand, ADMA might contribute to brain injury by reduction of cerebral blood flow. On the other hand, ADMA might be involved in NOS-induced oxidative stress and excitotoxic neuronal death. In the present review, we highlight the current knowledge from clinical and experimental studies on ADMA and its role for stroke risk and ischemic brain injury in the hyperacute stage after stroke. Finally, further studies are warranted to unravel the relevance of the close association of dimethylarginines with stroke.
Isolation and Characterization of Polymorphic Microsatellite Markers from the Chinese Medicinal Herb Atractylodes macrocephala (Asteraceae)
Authors: Zheng Li , Shao Zhong-Da , Wang Zong-Chao , Fu Cheng-Xin
Published: November 2012

Atractylodes macrocephala Koidz. (Asteraceae) is an economically important Chinese medicinal herb. In this study, 15 polymorphic microsatellite markers were developed from A. macrocephala using the compound microsatellite marker technique. Levels of polymorphism within the 15 markers were assessed using 83 individuals from two wild and two cultivated populations in China. The number of alleles per locus ranged from 2 to 20, with an average of 9.9 alleles. Observed and expected heterozygosities ranged from 0.083 to 1.000 and from 0.097 to 0.938, respectively. These markers will be valuable for germplasm classiﬁcation and identiﬁcation, as well as for assessing the genetic diversity and spatial genetic structure among wild and cultivated populations of A. macrocephala.
Quaternionic Multilayer Perceptron with Local Analyticity
Authors: Isokawa Teijiro , Nishimura Haruhiko , Matsui Nobuyuki
Published: November 2012

A multi-layered perceptron type neural network is presented and analyzed in this paper. All neuronal parameters such as input, output, action potential and connection weight are encoded by quaternions, which are a class of hypercomplex number system. Local analytic condition is imposed on the activation function in updating neurons’ states in order to construct learning algorithm for this network. An error back-propagation algorithm is introduced for modifying the connection weights of the network.
Range-Free Localization in Wireless Sensor Networks with Neural Network Ensembles
Authors: Zheng Jun , Dehghani Asghar
Published: November 2012

In wireless sensor networks (WSNs), the location information of sensor nodes are important for implementing other network applications. In this paper, we propose a range-free Localization algorithm based on Neural Network Ensembles (LNNE). The location of a sensor node is estimated by LNNE solely based on the connectivity information of the WSN. Through simulation study, the performance of LNNE is compared with that of two well-known range-free localization algorithms, Centroid and DV-Hop, and a single neural network based localization algorithm, LSNN. The experimental results demonstrate that LNNE consistently outperforms other three algorithms in localization accuracy. An enhanced mass spring optimization (EMSO) algorithm is also proposed to further improve the performance of LNNE by utilizing the location information of neighboring beacon and unknown nodes.
Glycomics Approaches for the Bioassay and Structural Analysis of Heparin/Heparan Sulphates
Authors: Puvirajesinghe Tania , Turnbull Jeremy
Published: November 2012

The glycosaminoglycan heparan sulphate (HS) has a heterogeneous structure; evidence shows that specific structures may be responsible for specific functions in biological processes such as blood coagulation and regulation of growth factor signalling. This review summarises the different experimental tools and methods developed to provide more rapid methods for studying the structure and functions of HS. Rapid and sensitive methods for the facile purification of HS, from tissue and cell sources are reviewed. Data sets for the structural analysis are often complex and include multiple sample sets, therefore different software and tools have been developed for the analysis of different HS data sets. These can be readily applied to chromatographic data sets for the simplification of data (e.g., charge separation using strong anion exchange chromatography and from size separation using gel filtration techniques. Finally, following the sequencing of the human genome, research has rapidly advanced with the introduction of high throughput technologies to carry out simultaneous analyses of many samples. Microarrays to study macromolecular interactions (including glycan arrays) have paved the way for bioassay technologies which utilize cell arrays to study the effects of multiple macromolecules on cells. Glycan bioassay technologies are described in which immobilisation techniques for saccharides are exploited to develop a platform to probe cell responses such as signalling pathway activation. This review aims at reviewing available techniques and tools for the purification, analysis and bioassay of HS saccharides in biological systems using “glycomics” approaches.
Effect of Sludge Amendment on Remediation of Metal Contaminated Soils
Authors: Navarro Andrés
Published: November 2012

Column-leaching and pilot-scale experiments were conducted to evaluate the use of biosolids (sewage sludges) to control the mobilization of metals from contaminated soils with smelting slags. The pilot-scale experiments using amended soils showed that Cu, Pb and Sb were retained, decreasing their concentrations from 250 mg/L, 80 mg/L and 6 mg/L, respectively in the leachates of contaminated soils, to <20 mg/L, 40 mg/L and 4 mg/L, respectively, in the amended material. Hydrogeochemical modeling of the leachates using Minteq revealed that the degree of complexation of Cu rose 56.3% and 57.6% in leachates of amended soils. Moreover, Cu may be immobilized by biosolids, possibly via adsorption by oxyhydroxides of Fe or sorption by organic matter. The partial retention of Pb coincides with the possible precipitation of chloropyromorphite, which is the most stable mineral phase in the pH-Eh conditions of the leachates from the amended material. The retention of Sb may be associated with the precipitation of Sb2O3, which is the most stable mineral phase in the experimental conditions. The organic amendments used in this study increased some metal and metalloid concentrations in the leachates (Fe, Mn, Ni, As and Se), which suggests that the organic amendments could be used with caution to remediate metal contaminated areas.
Fluorescent Probes and Fluorescence (Microscopy) Techniques — Illuminating Biological and Biomedical Research
Authors: Drummen Gregor
Published: November 2012

Fluorescence, the absorption and re-emission of photons with longer wavelengths, is one of those amazing phenomena of Nature. Its discovery and utilization had, and still has, a major impact on biological and biomedical research, since it enables researchers not just to visualize normal physiological processes with high temporal and spatial resolution, to detect multiple signals concomitantly, to track single molecules in vivo, to replace radioactive assays when possible, but also to shed light on many pathobiological processes underpinning disease states, which would otherwise not be possible. Compounds that exhibit fluorescence are commonly called fluorochromes or fluorophores and one of these fluorescent molecules in particular has significantly enabled life science research to gain new insights in virtually all its sub-disciplines: Green Fluorescent Protein. Because fluorescent proteins are synthesized in vivo, integration of fluorescent detection methods into the biological system via genetic techniques now became feasible. Currently fluorescent proteins are available that virtually span the whole electromagnetic spectrum. Concomitantly, fluorescence imaging techniques were developed, and often progress in one field fueled innovation in the other. Impressively, the properties of fluorescence were utilized to develop new assays and imaging modalities, ranging from energy transfer to image molecular interactions to imaging beyond the diffraction limit with super-resolution microscopy. Here, an overview is provided of recent developments in both fluorescence imaging and fluorochrome engineering, which together constitute the “fluorescence toolbox” in life science research.
Allylation of Functionalized Aldehydes by Potassium Allyltrifluoroborate Catalyzed by 18-Crown-6 in Aqueous Media
Authors: Barbosa Fernanda , Freitas Juliano , Melo Caio , Menezes Paulo , Oliveira Roberta
Published: November 2012

An efficient method for the allylation of aldehydes containing a broad range of functional groups using potassium allyltrifluoroborate is described. The reaction utilizes a catalytic amount of 18-C-6 in biphasic media under open atmosphere and room temperature to provide the corresponding homoallylic alcohols in high yields and without the necessity of any subsequent purification.
Design, Synthesis, Antinociceptive and Anti-Inflammatory Activities of Novel Piroxicam Analogues
Authors: De Miranda Amanda , Júnior Walfrido , Da Silva Yolanda , Alexandre-Moreira Magna , Castro Rosane , Sabino José , Lião Luciano , Lima Lídia , Barreiro Eliezer
Published: November 2012

In this paper we report the design, synthesis, antinociceptive and anti-inflammatory activities of a series of benzothiazine N-acylhydrazones 14a–h, planned by structural modification of piroxicam (1), a non steroidal anti-inflammatory drug. Among the synthesized analogues, compounds 14f (LASSBio-1637) and 14g (LASSBio-1639) were identified as novel antinociceptive and anti-inflammatory prototypes, active by oral administration, acting by a mechanism of action that seems to be different from that of piroxicam, since they were inactive as an inhibitor of cyclooxygenase (COX-1 and COX-2) at concentrations of 10 mM.
Studies on the Interaction Mechanism of Pyrene Derivatives with Human Tumor-Related DNA
Authors: Li Li , Lu Jia , Xu Chongzheng , Li Huihui , Yang Xiaodi
Published: November 2012

Pyrene derivatives can be carcinogenic, teratogenic and mutagenic, thus having the potential to cause malignant diseases. In this work, the interactions of two selected pyrene derivatives (1-OHP and 1-PBO) and human tumor-related DNA (p53 DNA and C-myc DNA) are investigated by spectroscopic and non-native polyacrylamide gel electrophoresis (PAGE) methods. Using fluorescence spectrometry and circular dichroism (CD), DNA interactions of pyrene derivatives are confirmed to occur mainly via the groove binding mode supported by the intercalation into the base pairs of DNA. There is an obvious binding order of pyrene derivatives to the targeted DNA, 1-OHP > 1-PBO. The binding constants of 1-OHP are 1.16 × 106 L×mol−1 and 4.04 × 105 L×mol−1 for p53 DNA and C-myc DNA, respectively, while that of 1-PBO are only 2.04 × 103 L×mol−1 and 1.39 × 103 L×mol−1 for p53 DNA and C-myc DNA, respectively. Besides, the binding of pyrene derivatives to p53 DNA is stronger than that for C-myc DNA. CD and PAGE results indicate that the binding of pyrene derivatives can affect the helical structures of DNA and further induce the formation of double-chain antiparallel G-quadruplex DNA of hybrid G-rich sequences.
Dietary Regulation of Histone Acetylases and Deacetylases for the Prevention of Metabolic Diseases
Authors: Pham Tho , Lee Jiyoung
Published: November 2012

Age-related diseases such as type 2 diabetes, cardiovascular disease, and cancer involve epigenetic modifications, where accumulation of minute changes in the epigenome over time leads to disease manifestation. Epigenetic changes are influenced by life style and diets. This represents an avenue whereby dietary components could accelerate or prevent age-related diseases through their effects on epigenetic modifications. Histone acetylation is an epigenetic modification that is regulated through the opposing action of histone acetylases (HATs) and deacetylases (HDACs). These two families of enzymes play critical roles in metabolic processes and their dysregulation is associated with pathogenesis of several diseases. Dietary components, such as butyrate, sulforaphane, and curcumin, have been shown to affect HAT and HDAC activity, and their health benefits are attributed, at least in part, to epigenetic modifications. Given the decades that it takes to accumulate epigenetic changes, it is unlikely that pharmaceuticals could undo epigenetic changes without side effects. Therefore, long term consumption of dietary components that can alter the epigenome could be an attractive means of disease prevention. The goal of this review is to highlight the roles of diets and food components in epigenetic modifications through the regulation of HATs and HDACs for disease prevention.
Digital Sun Sensor Multi-Spot Operation
Authors: Rufino Giancarlo , Grassi Michele
Published: November 2012

The operation and test of a multi-spot digital sun sensor for precise sun-line determination is described. The image forming system consists of an opaque mask with multiple pinhole apertures producing multiple, simultaneous, spot-like images of the sun on the focal plane. The sun-line precision can be improved by averaging multiple simultaneous measures. Nevertheless, the sensor operation on a wide field of view requires acquiring and processing images in which the number of sun spots and the related intensity level are largely variable. To this end, a reliable and robust image acquisition procedure based on a variable shutter time has been considered as well as a calibration function exploiting also the knowledge of the sun-spot array size. Main focus of the present paper is the experimental validation of the wide field of view operation of the sensor by using a sensor prototype and a laboratory test facility. Results demonstrate that it is possible to keep high measurement precision also for large off-boresight angles.
Chirped Laser Dispersion Spectroscopy for Remote Open-Path Trace-Gas Sensing
Authors: Nikodem Michal , Wysocki Gerard
Published: November 2012

In this paper we present a prototype instrument for remote open-path detection of nitrous oxide. The sensor is based on a 4.53 μm quantum cascade laser and uses the chirped laser dispersion spectroscopy (CLaDS) technique for molecular concentration measurements. To the best of our knowledge this is the first demonstration of open-path laser-based trace-gas detection using a molecular dispersion measurement. The prototype sensor achieves a detection limit down to the single-ppbv level and exhibits excellent stability and robustness. The instrument characterization, field deployment performance, and the advantages of applying dispersion sensing to sensitive trace-gas detection in a remote open-path configuration are presented.
General Resilience to Cope with Extreme Events
Authors: Carpenter Stephen , Arrow Kenneth , Barrett Scott , Biggs Reinette , Brock William , Crépin Anne-Sophie , Engström Gustav , Folke Carl , Hughes Terry , Kautsky Nils , Li Chuan-Zhong , McCarney Geoffrey , Meng Kyle , Mäler Karl-Göran , Polasky Stephen , Scheffer Marten , Shogren Jason , Sterner Thomas , Vincent Jeffrey , Walker Brian , Xepapadeas Anastasios , Zeeuw Aart
Published: November 2012

Resilience to specified kinds of disasters is an active area of research and practice. However, rare or unprecedented disturbances that are unusually intense or extensive require a more broad-spectrum type of resilience. General resilience is the capacity of social-ecological systems to adapt or transform in response to unfamiliar, unexpected and extreme shocks. Conditions that enable general resilience include diversity, modularity, openness, reserves, feedbacks, nestedness, monitoring, leadership, and trust. Processes for building general resilience are an emerging and crucially important area of research.
Diagnostic value and therapeutic impact of 18F-FDG-PET/CT in differentiated thyroid cancer
Authors: Dietlein M. , Schmidt D. , Kuwert T. , Dorn R. , Sciuk J. , Kodalle T. , Schober O. , Riemann B. , Uhrhan K.
Published: November 2012

The clinical significance of 18F-FDG-PET/CT in the follow-up of patients with differentiated thyroid carcinoma was evaluated and the results were compared with those of 18F-FDGPET, 131I-whole-body scintigraphy including SPECT/CT (WBS) and ultrasound. In addition, it was the aim to investigate the impact of 18F-FDG-PET/CT on the therapeutic management. Patients, methods: 327 patients (209 women, 118 men; mean age 53 ± 18 years) with differentiated thyroid cancer (242 papillary, 75 follicular, 6 mixed, 1 Hürthle cell and 3 poorly differentiated tumours) were analyzed retrospectively at four tertiary referral centres. 289 18F-FDG-PET/CT and 118 18F-FDG-PET studies were performed in these patients between 2007 and 2010. In addition, an overall clinical evaluation was performed, including cytology, histology, thyroglobulin level, ultrasound, WBS, and subsequent clinical course in order to compare the molecular imaging results. Finally, the change in therapeutic management due to findings of 18F-FDG-PET/CT was investigated. Results: The sensitivity of 18F-FDG-PET/CT was 92%, the specificity was 95%. Sensitivity and specificity of 18F-FDG-PET alone were 67% and 93%, respectively. WBS showed a sensitivity of 65% and a specificity of 94%. The corresponding values of ultrasound were 37% and 94%, respectively. The sensitivity of 18F-FDG-PET/CT in the group of patients with a negative WBS (n=194) amounted to 96%. When 18F-FDG-PET/CT and WBS were considered in combination, tumour tissue was missed in only 2 out of 133 patients; when 18F-FDG-PET and WBS were combined, tumour tissue was missed in 1 out of 24 patients. 18F-FDG-PET/CT resulted in management change in 43% (n=57/133) with a decision on surgical approach in 20% (n=27/133). Conclusions: 18F-FDG-PET/CT is superior to 18F-FDG-PET alone in patients with differentiated thyroid cancer and has a direct impact on the therapeutic management of patients with suspected local recurrence or metastases, particularly in those with negative WBS.
Application of Microarray Analysis on Computer Cluster and Cloud Platforms
Authors: Boulesteix A.-L. , Knaus J. , Bernau C.
Published: November 2012

Background: Analysis of recent high-dimensional biological data tends to be computationally intensive as many common approaches such as resampling or permutation tests require the basic statistical analysis to be repeated many times. A crucial advantage of these methods is that they can be easily parallelized due to the computational independence of the resampling or permutation iterations, which has induced many statistics departments to establish their own computer clusters. An alternative is to rent computing resources in the cloud, e.g. at Amazon Web Services.

Objectives: In this article we analyze whether a selection of statistical projects, recently implemented at our department, can be efficiently realized on these cloud resources. Moreover, we illustrate an opportunity to combine computer cluster and cloud resources.

Methods: In order to compare the efficiency of computer cluster and cloud implementations and their respective parallelizations we use microarray analysis procedures and compare their runtimes on the different platforms.

Results: Amazon Web Services provide various instance types which meet the particular needs of the different statistical projects we analyzed in this paper. Moreover, the network capacity is sufficient and the paralleli -zation is comparable in efficiency to standard computer cluster implementations.

Conclusion: Our results suggest that many statistical projects can be efficiently realized on cloud resources. It is important to mention, however, that workflows can change substantially as a result of a shift from computer cluster to cloud computing.
Costs of Cloud Computing for a Biometry Department
Authors: Hieke S. , Binder H. , Schwarzer G. , Knaus J.
Published: November 2012

Background: “Cloud” computing providers, such as the Amazon Web Services (AWS), offer stable and scalable computational resources based on hardware virtualization, with short, usually hourly, billing periods. The idea of pay-as-you-use seems appealing for biometry research units which have only limited access to university or corporate data center resources or grids.

Objectives: This case study compares the costs of an existing heterogeneous on-site hardware pool in a Medical Biometry and Statistics department to a comparable AWS offer.

Methods: The “total cost of ownership”, including all direct costs, is determined for the on-site hardware, and hourly prices are derived, based on actual system utilization during the year 2011. Indirect costs, which are difficult to quantify are not included in this comparison, but nevertheless some rough guidance from our experience is given. To indicate the scale of costs for a methodological research project, a simulation study of a permutation-based statistical approach is performed using AWS and on-site hardware.

Results: In the presented case, with a system utilization of 25 –30 percent and 3 – 5-year amortization, on-site hardware can result in smaller costs, compared to hourly rental in the cloud dependent on the instance chosen. Renting cloud instances with sufficient main memory is a deciding factor in this comparison.

Conclusions: Costs for on-site hardware may vary, depending on the specific infrastructure at a research unit, but have only moderate impact on the overall comparison and subsequent decision for obtaining affordable scientific computing resources. Overall utilization has a much stronger impact as it determines the actual computing hours needed per year. Taking this into account, cloud computing might still be a viable option for projects with limited maturity, or as a supplement for short peaks in demand.
B-Cell Depletion Improves Islet Allograft Survival with Anti-CD45RB
Authors: Lee Kang Mi , Yeh Heidi , Zhao Gaoping , Wei Lingling , O'connor Matthew , Stott Ryan T. , Soohoo Julie , Dunussi Kyri , Fiorina Paolo , Deng Shaoping , Markmann James F. , Kim James I.
Published: November 2012

A short course of anti-CD45RB leads to long-term islet allograft survival and donor-specific tolerance in approximately half of immunocompetent mice. We have previously demonstrated that anti-CD45RB antibody-mediated tolerance requires B-cells for cardiac allograft survival. We therefore asked whether B-cells were also required for anti-CD45RB antibody-mediated survival of islets. Unexpectedly, we found that nearly 100% of islet allografts survive long term in B-cell-deficient mice. Similarly, B-cell depletion by anti-CD22/cal augmented anti-CD45RB-mediated tolerance when administered pretransplant, although it had no effect on tolerance induction when administered posttransplant. Our results demonstrate that the role of B-cells in promoting tolerance with anti-CD45RB is graft specific, promoting tolerance in cardiac grafts but resisting tolerance in islet transplantation. These findings may help elucidate the varied action of B-cells in promoting tolerance versus rejection.
Myeloid-Derived Suppressor Cells are Generated during Retroviral Transduction of Murine Bone Marrow
Authors: Gomez Alba , Espejo Carmen , Eixarch Herena , Casacuberta-Serra Silvia , Mansilla Maria Jose , Sanchez Rebeca , Pereira Sonia , Lopez-Estevez Sergio , Gimeno Ramon , Montalban Xavier , Barquinero Jordi
Published: November 2012

Previous work by our group showed that transferring bone marrow cells transduced with an autoantigen into nonmyeloablated mice with experimental autoimmune encephalomyelitis induced immune tolerance and improved symptoms of the disease. Because this effect occurred in the absence of molecular chimerism, we hypothesized that the cells responsible did not have repopulating ability and that they were not mediating central but peripheral tolerance mechanisms. In the present study, we analyzed the immunophenotype of the cells that are generated in the transduction cultures and we evaluated the immunosuppressive activity of the main cell subpopulations produced. We show that both granulocytic (CD11b+Gr-1hi) and monocytic (CD11b+Gr-1lo) myeloid-derived suppressor cells (G- and M-MDSCs, respectively) are generated during standard 4-day γ-retroviral transduction cultures (representing about 25% and 40% of the total cell output, respectively) and that the effectively transduced cells largely consist of these two cell types. A third cell population representing about 15% of the transduced cells did not express CD45 or hematopoietic lineage markers and expressed mesenchymal stromal cell markers. Transduced total bone marrow cells and sorted M-MDSCs expressed arginase and inducible nitric oxide synthase activities, produced reactive oxygen species, and inhibited antigen-induced T-cell proliferation in vitro. Transgene-expressing MDSCs could be exploited therapeutically to induce tolerance in autoimmune diseases and in gene therapy protocols.
Implementing a pharmacovigilance program to evaluate cutaneous adverse drug reactions in an antiretroviral access program
Authors: Mudzviti Tinashe , Sibanda Marvelous , Gavi Samuel , Maponga Charles Chiedza , Morse Gene D
Published: November 2012

Introduction: Cutaneous adverse drug reactions (cADRs) can cause significant morbidity and distress in patients, especially in the HIV-infected population on antiretroviral therapy. Adverse drug reaction monitoring and ascertaining causality in resource-limited settings remain serious challenges. This study was conducted to evaluate causality and measure the incidence of cADRs in HIV-infected patients on highly active antiretroviral therapy. The study was also designed to test a three-step approach in the monitoring and evaluation of ADRs in resource-limited settings. Methodology: A retrospective review of patient medical records was performed at the Parirenyatwa Family Care Centre, Harare, Zimbabwe. Cases of cADRs were reported to the Medicines Control Authority of Zimbabwe, the main drug regulating body in Zimbabwe, for assessment and causality classification. Results: We reviewed 221 randomly selected patient records to determine whether any diagnoses of cADRs were made by clinicians. Causality assessment revealed that 13.1% of cADRs were due to an offending agent in the antiretroviral therapy versus an initial incidence of 17.6% which had been determined by the physicians. Conclusions: cADRs had an incidence of 13.1% within the population under study due to non nucleoside reverse transcriptase inhibitors (NNRTIs). Most reactions were caused by the NNRTIs which contributed 72.4 % of all cADRs. A panel of experts from the drug regulatory authority can be used as an implementation based mechanism in ascertaining causality objectively in settings where resources are constrained.