bluuebunny/crossref_metadata_2025 huggingface dataset:
Competitividade de capim-pé-de-galinha com soja
Authors: Wandscheer Alana Cristina Dorneles , Rizzardi Mauro Antônio , Reichert Muriel , Gaviraghi Fernando
Published: November 2013

A competição é uma interferência negativa, na qual indivíduos competem por recursos do meio. Objetivou-se avaliar a competitividade do capim-pé-de-galinha com soja. O experimento foi realizado em casa-de-vegetação, em delineamento inteiramente casualizado e quatro repetições. Os tratamentos foram cinco proporções da cultura e da espécie daninha, respectivamente, 8:0, 6:2, 4:4, 2:6 e 0:8, que correspondeu a 100, 75, 50, 25 e 0% de plantas de soja, e o inverso para o capim-pé-de-galinha, com população final constante de oito plantas vaso-1 (8 L), correspondendo a aproximadamente 250 plantas m-2. A análise da competitividade foi realizada por meio de diagramas aplicados a experimentos substitutivos e índices de competitividade. A soja apresentou competitividade superior ao capim-pé-de-galinha para as variáveis de matéria seca, quando ambos estavam em proporções iguais de plantas.
In vitro behaviour of Aspasia variegata, an epiphytic orchid from the Brazilian Cerrado
Authors: Paiva Neto Vespasiano Borges de , Campos Guilherme de Oliveira , Boaretto Amanda Galdi , Zuffo Monica Cristina Rezende , Torrezan Mateus de Aguiar , Benetão Jamile
Published: November 2013

Aspasia variegata occurs naturally in the savanna of the Mato Grosso do Sul State, Brazil and it has been widely collected for its beautiful flowers. Additionally, its habitat has been greatly reduced and little or no investigation of its spread has been performed. Aiming to establish a protocol to obtain seedlings of the orchid A. variegata, different compositions of culture medium were tested to identify which one provided better in vitro growth and development and to assess the influence of these media in seedling acclimatisation. Thus, seeds obtained from mature capsules were inoculated in Knudson culture medium for 120 days until the protocorm stage. They were transferred to different culture media formulations, including MS and Knudson with half or full formulation, and 3.0 and 6.0g L-1 activated charcoal were added to them or not. After 180 days of protocorm inoculation, seedlings were evaluated for length of roots and shoots, number of roots and leaves, and chlorophyll contents. After that, seedlings were transferred to trays containing a mixture of Plantmax® and coconut fibre (1:1) for acclimatisation. Best results for the in vitro growth of A. variegata were obtained with the use of MS medium supplemented with 6.0g L-1 activated charcoal. Higher levels of chlorophyll were obtained, however, in treatments containing MS salts without activated charcoal presence, and lower levels in media containing Knudson salts with the presence of activated charcoal. The seedlings originated by higher chlorophyll levels during in vitro cultivation presented the highest survival rates and better development in the acclimatisation phase.
Influência da atmosfera na sinterização do cromito de lantânio dopado
Authors: Setz L. F. G. , Mello-Castanho S. R. H. , Santacruz I. , Moreno R. , Colomer M. T.
Published: November 2013

O cromito de lantânio (LaCrO3) para ser utilizado como interconector em células a combustível de óxido sólido, ademais de possuir condutividade elétrica adequada, deve apresentar alta densidade, contribuindo com a estanqueidade dos gases utilizados. Utilizando LaCrO3 dopado com Sr e Co sintetizado por combustão, estudou-se o efeito das atmosferas inerte (argônio) e oxidante (ar) no comportamento de sinterização e densificação. As peças foram sinterizadas em dilatômetro, caracterizadas com difração de raios X e as densidades foram determinadas pelo método de Arquimedes. Na observação das microestruturas formadas utilizou-se microscopia eletrônica de varredura. Os resultados mostram que as duas atmosferas favorecem a densificação do cromito de lantânio dopado; porém, ciclos térmicos em meios oxidantes podem prejudicar o desempenho do material quando em utilização como interconector.
Catalytic activity of aluminum silicate for ozonation of chloronitrobenzenes in aqueous solution
Authors: Liu Y. , Shen J. M. , Chen Z. L. , Yuan L. , Liu Y.
Published: November 2013

Chemical oxidation using ozone with appropriate catalysts offers an attractive option for removing inhibitory and toxic pollutants in micro-polluted water. This work investigated the catalytic ozonation of three chloronitrobenzenes (CNBs, i.e. p-CNB, o-CNB, and m-CNB) in the presence of a novel and efficient synthesized aluminum silicate catalyst. Experiments were carried out with focus on the degradation efficiency of CNBs at different reaction pH values, water matrices and repeated uses, as well as the possible catalytic mechanism. Regardless of the water matrix, the results showed that the catalytic ozonation had considerably higher degradation efficiency of CNBs than the single ozonation process at the same ozone dose. The change of pH had an obvious effect on the removal efficiency of CNBs, which suggested that the aluminum silicate catalyst was more appropriate for application in the neutral pH condition. Ozonation processes in the presence of the aluminum silicate were significantly influenced by tert-butyl alcohol, which confirmed that the aluminum silicate catalytic ozonation followed a hydroxyl radical-type mechanism.
Hydrogel floc nature and biogenic constituents of drinking water discolouration deposits
Authors: Poças Ana , Miranda André , Paiva João , Benoliel M. J. , Vreeburg Jan , Menaia José
Published: November 2013

Loose deposits (LD) develop and accumulate in drinking water distribution systems' (DWDS) pipes and often lead to discolouration incidents, which are a major reason for customers' complaints. In addition, LD may accumulate contaminants, while discolouration may be accompanied by degradation of the water's microbiological quality. Along with iron oxides, organic compounds are well established as predominant constituents of LD. Even so, the composition and role of the latter remain unknown. Since microbial extracellular polymeric substances (EPS) are components of iron-rich flocs from many freshwater environments, the presence of EPS in LD was investigated. This was confirmed by the systematic occurrence of polysaccharides and proteins in LD samples. In addition, microscopic observations and measurements of LD water contents showed that, like their freshwater counterparts, LD have a hydrogel floc nature and fractal morphology. By providing insights on LD origin and behaviour, these findings may be important for the understanding of DWDS water discolouration phenomena.
The effect of an extensive use of meadow on moderately decomposed peat-muck soil on carbon balance / Wpływ ekstensywnego użytkowania łąki na średnio zmurszałej glebie torfowo-murszowej na bilans węgla
Authors: Turbiak Janusz
Published: November 2013

The study was aimed at estimating carbon balance in extensively used meadow ecosystem on moderately decomposed peat-muck soil. The balance was calculated from the measurements of CO2 emission determined with the closed static chamber method using diffusion recorders. During the vegetation period, 88.5 Mg·ha-1 CO2 were emitted from the meadow ecosystem while plants took up 65.9 Mg·ha-1 CO2. Carbon losses associated with yield harvesting expressed in the CO2 equivalent were 4.7 Mg·ha-1. Total carbon losses during the vegetation period expressed as CO2 amounted to 27.2 Mg·ha-1 on average for the whole study period. It means a loss of 7.4 Mg·ha-1 C or 13.2 Mg·ha-1 of organic matter of a carbon content of 56%. It was found that an extensive use of peat-muck soils increased carbon losses compared with moderately intensive use. Carbon losses in extensively used meadow ecosystems may be minimised by delaying the term of the first hay cut and by limiting the number of harvests.
The emotional intelligence of a group of critical-care nurses in South Africa
Authors: Towell Amanda , Nel Elzabe , Müller Ann
Published: November 2013

Critical-care nurses often look after three or more critically-ill patients during a shift. The workload and emotional stress can lead to disharmony between the nurse’s body, mind and spirit. Nurses with a high emotional intelligence have less emotional exhaustion and psychosomatic symptoms; they enjoy better emotional health; gain more satisfaction from their actions (both at work and at home); and have improved relationships with colleagues at work. The question arises: what is the emotional intelligence of critical-care nurses? A quantitative survey was conducted. The target population was registered nurses working in critical-care units who attended the Critical Care Congress 2009 (N = 380). Data were collected with the use of the Trait Emotional Intelligence Short Form and analysed using the Statistical Package for the Social Sciences software. The sample (n = 220) was mainly a mature, female and professionally-experienced group of registered nurses. They held a variety of job descriptions within various critical-care units. Statistics indicated that the standard deviations were small and no aberrant aspects such as demographics skewed the findings. The conclusion was made that registered nurses who are older and that have more experience in critical care appear to have a higher range of emotional intelligence.Kritiekesorg-verpleegkundiges verpleeg dikwels drie of meer pasiënte wat kritiek siek is, tydens een skof. Die werkslading kan tot emosionele spanning ly wat ’n wanbalans tussen die liggaam, siel en gees van die verpleegkundiges laat ontstaan. Verpleekundiges met ’n hoë emosionele intelligensie ondervind minder emosionele uitbranding en psigosomatiese symptome. Hulle toon ’n beter emosionele gesondheid, ervaar meer werks- en tuisbevrediging en het beter verhoudings met hulle kollegas. The vraag wat ontstaan is ‘wat is die emosionel intelligensie van kritieksorg-verpleegkundiges?’ Die toeganglike populasie (N = 380) was geregistreerde verpleegkundiges wat tans in die kritiek sorgeenhede werksaam was en die Critical Care Congress in 2009 bygewoon het. Die data is deur die gebruikmaking van die ‘Trait Emotional Intelligence Short Form’ vraelys ingesamel. Die data is statisties met behulp van die SPSS ontleed. Die populasie (n = 220) was hoofsaaklik n groepe volwasse, vroulike en professioneel ervare verpleegkundiges. Hulle het ’n verskeidenheid van posbeskrywing in die kritieke-sorgeenhede beklee. Die statistieke het ’n minimale standaardafwyking aangetoon. Die gevolgtrekking van die studie is dat geregistreede verpleegkundiges wat ouer en meer ervaring in kritieke sorgverpleging het, ’n hoër vlak van emosionele intelligensie het.
Key Elements of the Unitary Patent Package Adopted by the European Union
Authors: Benizri Yohan
Published: November 2013

For more than four decades, those who supported the creation of a single patent regime with European-wide legal effects must have felt a lot like Sisyphus, struggling pointlessly towards an unreachable goal. This may be about to change in light of the adoption of the “unitary patent package” by the European Union (EU), provided the thirteen Member States (including France, Germany, and the United Kingdom) ultimately ratify the Unified Patent Court Agreement (UPCA).
Impact of space weather events on satellite‐based navigation
Authors: Roy B. , Paul A.
Published: November 2013

Detrimental effects of the equatorial ionospheric irregularities on satellite‐based communication and navigation systems have been studied over the past few decades as space weather events have the potential to seriously disturb the technological infrastructure of modern society. The present paper tries to understand operational compliance of Global Positioning System (GPS) receivers to International Civil Aviation Organization (ICAO) standards under scintillation conditions by recording the received phase of the L1(1575.42 MHz) signal from two stations, namely Calcutta situated near the northern crest of the Equatorial Ionization Anomaly and Siliguri, situated beyond the northern crest, at a subionospheric latitude separation of 4° along the same meridian. A causative approach is adopted whereby GPS phase scintillations have been monitored and receiver performance prior to loss of lock and cycle slips have been analyzed during August–October 2011 at Calcutta and September 2011 at Siliguri. The received phase at GPS‐L1 frequency has often been found to fluctuate at kilohertz, often megahertz rates, thereby causing carrier‐tracking loop malfunctions. It should be borne in mind that normal GPS receivers' carrier‐tracking loops have a typical dynamic range of 14–18 Hz. Cycle slips have been observed with durations far exceeding ICAO specified levels for high dynamic platforms like aircrafts. Differences in cycle slips between Calcutta and Siliguri indicate possible evolution of irregularity structures even across small subionospheric swath. Significant improvement in present understanding of GPS phase scintillations should be developed and implemented in receiver designs prior to application of Satellite Based Augmentation System services for civil aviation, particularly in the geophysically sensitive equatorial region.
Pathogenesis of antibody‐induced acquired von willebrand syndrome
Authors: Gan Tong Eng , Sawers Ronald J. , Koutts Jerry
Published: November 2013

A patient with clinical and laboratory evidence of von Willebrand syndrome is described in association with an IgG‐kappa immunoglobulin and Bence‐Jones proteinuria due to a probable lymphoproliferative disorder. He had a persistently prolonged bleeding time of greater than 20 minutes, factor VIII related antigen (VIII: R. Ag), factor VIII procoagulant activity (VIII:C) and factor VIII ristocetin co‐factor (VIIIR: Rcof) below 10%. Following cryoprecipitate or high purity factor VIII concentrate infusion, he had the expected immediate rise in VIII:C, VIII: R. Ag, and VIIIR: Rcof, but there was a rapid decline in all three components within two hours. The larger forms of VIII: R. Ag were preferentially removed from the plasma, and this paralleled the fall in plasma VIIIR: Rcof level. However, no inhibitory activity could be demonstrated in vitro using the patient's plasma or IgG. Using protein A it was possible to demonstrate that his plasma or IgG bound factor VIII and that this complex retained its biological activity in vitro. It is postulated that the monoclonal IgG forms complexes with factor VIII in vivo and these are rapidly removed by the reticuloendothelial system (RES).
Determination of ampicillin sodium using the cupric oxide nanoparticles–luminol–H2O2 chemiluminescence reaction
Authors: Iranifam Mortaza , Kharameh Merhnaz Khabbaz
Published: November 2013

A simple and sensitive chemiluminescence (CL) method has been developed for the determination of ampicillin sodium at submicromolar levels. The method is based on the inhibitory effect of ampicillin sodium on the cupric oxide nanoparticles (CuO NPs)–luminol–H2O2 CL reaction. Experimental parameters affecting CL inhibition including concentrations of CuO NPs, luminol, H2O2 and NaOH were optimized. Under optimum conditions, the calibration plot was linear in the analyte concentration range 4.0 × 10‐7–4.0 × 10‐6 mol/L. The limit of detection was 2.6 × 10‐7 mol/L and the relative standard deviation (RSD) for six replicate determinations of 1 × 10‐6 mol/L ampicillin sodium was 4.71%. Also, X–ray diffraction (XRD) and transmission electron microscopy (TEM) analysis were employed to characterize the CuO NPs. The utility of the proposed method was demonstrated by determining ampicillin sodium in pharmaceutical preparation. Copyright © 2013 John Wiley & Sons, Ltd.
Computational fluid model incorporating liver metabolic activities in perfusion bioreactor
Authors: Hsu Myat Noe , Tan Guo‐Dong Sean , Tania Marshella , Birgersson Erik , Leo Hwa Liang
Published: November 2013

The importance of in vitro hepatotoxicity testing during early stages of drug development in the pharmaceutical industry demands effective bioreactor models with optimized conditions. While perfusion bioreactors have been proven to enhance mass transfer and liver specific functions over a long period of culture, the flow‐induced shear stress has less desirable effects on the hepatocytes liver‐specific functions. In this paper, a two‐dimensional human liver hepatocellular carcinoma (HepG2) cell culture flow model, under a specified flow rate of 0.03 mL/min, was investigated. Besides computing the distribution of shear stresses acting on the surface of the cell culture, our numerical model also investigated the cell culture metabolic functions such as the oxygen consumption, glucose consumption, glutamine consumption, and ammonia production to provide a fuller analysis of the interaction among the various metabolites within the cell culture. The computed albumin production of our 2D flow model was verified by the experimental HepG2 culture results obtained over 3 days of culture. The results showed good agreement between our experimental data and numerical predictions with corresponding cumulative albumin production of 2.9 × 10−5 and 3.0 × 10−5 mol/m3, respectively. The results are of importance in making rational design choices for development of future bioreactors with more complex geometries. Biotechnol. Biotechnol. Bioeng. 2014;111: 885–895. © 2013 Wiley Periodicals, Inc.
The nature of the second dimension in 2D NMR
Authors: Traficante Daniel D.
Published: November 2013

A two‐dimensional (2D) NMR spectrum is produced from the double Fourier Transform (FT) of two time domains, t1 and t2. One of these domains, t2, is identical to the acquisition time used to collect a Free Induction Decay (FID) in one‐dimensional (1D) NMR spectroscopy. After performing the FTs of a series of these FIDs, an array of resonance lines is obtained whose amplitudes and phases are a function of t1. The t1 domain is then composed of another series of “FIDs” that are related to those collected during t2. In this article, it is shown that in a heteronuclear‐J, δ gated‐decoupling experiment, the “FIDs” in the t1 domain produce, after the FT, proton‐coupled spectra whose sum is identical to that obtained from a 1D carbon FID collected with no proton decoupling.
Optimization of an RFID location identification scheme based on the neural network
Authors: Kung Hsu‐Yang , Chaisit Sumalee , Phuong Nguyen Thi Mai
Published: November 2013

An indoor localization technology is increasingly critical as location‐aware applications evolve. Researchers have proposed several indoor localization technologies. Because most of the proposed indoor localization technologies simply involve using the received signal strength indicator value of radio‐frequency identification (RFID) for indoor localization, radio‐frequency interference, and environmental factors often limit the accuracy of localization results. Therefore, this study proposes an accurate RFID localization based on the neural network (ARL‐N2), a passive RFID indoor localization scheme for identifying tag positions in a room, combining a location identification based on dynamic active RFID calibration algorithm with a backpropagation neural network (BPN). The proposed scheme composed of two phases: in the training phase, an appropriate BPN architecture is constructed using the training data derived from the coordinates of reference tags and the coordinates obtained using the localization algorithm. By contrast, the online phase involves calculating the tracking tag coordinates and using these values as BPN inputs, thereby enhancing the estimated location. A performance evaluation of the ARL‐N2 schemes confirms its high localization accuracy. The proposed method can be used to locate critical objects in difficult‐to‐find areas by creating minimal errors and applying and economical technique. Copyright © 2013 John Wiley & Sons, Ltd.
Comparative Climate Change Governance: Lessons from European Transnational Municipal Network Management Efforts
Authors: Giest Sarah , Howlett Michael
Published: November 2013

Cities and municipalities are vital actors in addressing climate change. Because they are directly affected by the consequences of environmental transformations, cities are motivated to shape adaptation and mitigation. This paper looks at the possible mechanisms which cities can use to engage in climate change issues without decoupling themselves from the national or sub‐national level and while remaining consistent with other local initiatives. The paper analyses the European approach towards transnational municipal networks (TMNs) and community collective efforts and assesses its possible application in other jurisdictions. We argue that while TMNs are the institutional foundation for a concerted effort in climate change within and between countries; they are also subject to provisions from national and regional governments, which might hamper their benefits. Based on a typology of TMNs and an analysis of the national contexts, the paper finds that those networks that target a specific region and are supported by government have the most benefits for climate change. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment.
Development and validation of a capillary electrophoresis method for determination of enantiomeric purity and related substances of esomeprazole in raw material and pellets
Authors: Estevez Pablo , Flor Sabrina , Boscolo Oriana , Tripodi Valeria , Lucangioli Silvia
Published: November 2013

A capillary electrophoresis method using CDs for quality control of esomeprazole (ESO) in terms of enantiomeric purity and related substances in raw material and pellets was developed. ESO is the S‐enantiomer of omeprazole (OMZ). Several parameters were evaluated, including type and concentration of buffer and CD, concentration of additives and electrolyte pH. Resolution between the enantiomers of OMZ obtained for each parameter tested was calculated and the presence of the main related substance such as OMZ sulfone was carefully monitored. The optimized system consisted of 100 mM Tris‐phosphate buffer pH 2.5 with 20 mM 2‐hydroxypropyl‐β‐CD, 1 mM sodium dithionite, temperature at 15°C, voltage at 28 kV, and UV detection at 301 nm. Once optimized, the electrophoretic system was validated according to ICH guidelines. The limits of detection and quantification for R‐OMZ were 0.6 μg/mL (0.06% w/w of ESO) and 2.0 μg/mL (0.2% w/w of ESO), respectively. A mean concentration of R‐OMZ <0.2% limit established by the United States Pharmacopeia (USP) was found in the raw material and six‐pellet samples of ESO. No other impurities were found in the samples under these conditions. Therefore, the developed method was found to be appropriate not only for enantiomeric quality control of ESO but also for the analysis of ESO and the main related substance in raw material and pharmaceutical formulations as well as for stability indicating studies.
Functionality of dielectrophoretically immobilized enzyme molecules
Authors: Laux Eva‐Maria , Kaletta Udo C. , Bier Frank F. , Wenger Christian , Hölzel Ralph
Published: November 2013

The enzyme horseradish peroxidase has been immobilized on nanoelectrode arrays by alternating current dielectrophoresis (DEP). Preservation of its enzymatic function after field application was demonstrated by oxidizing dihydrorhodamine 123 with hydrogen peroxide as co‐oxidant to create its fluorescent form, rhodamine 123 (Rh123). Localization of the fluorescently labeled enzyme and its product was conducted by fluorescence microscopy. Nanoelectrodes were prepared as tungsten pins arranged in square arrays. Experimental parameters for dielectrophoretic immobilization were optimized for even enzyme distribution and for enzymatic efficiency. Enzyme activity was quantified by determination of fluorescence intensities of immobilized enzyme molecules and of Rh123 produced. These results demonstrate that DEP can be applied to immobilize enzyme molecules while retaining their activity and rendering any chemical modifications unnecessary. This introduces a novel way for the preparation of bioactive surfaces for processes such as biosensing.
Automated fast filtration and on‐filter quenching improve the intracellular metabolite analysis of microorganisms
Authors: da Luz Julian A. , Hans Enrico , Zeng An‐Ping
Published: November 2013

To reliably determine intracellular metabolite concentrations in microorganisms, accurate sampling and sample inactivation strategies are crucial. Here, we present a method for automated fast filtration and on‐filter quenching of microbial samples to overcome metabolite leakage induced by cold shock and significantly reduce the sampling and treatment time compared to manual filtration methods. The whole process of sampling, sample filtration, filter wash, and quenching of the filter with liquid nitrogen was finished in less than 6–15 s, depending on the experimental setup. By integration into an automated fast sampling device, we compared our method to the conventional methanol quenching method and showed that intracellular amino acid contents in Escherichia coli were significantly increased (≥75%) with our fast filtration and on‐filter quenching method. Furthermore, we investigated different filter types for the fast filtration and the efficiency of metabolite extraction from cells held on filters. Additionally, we found that the fast filtration behaves considerably different during exponential and nonexponential growth, probably due to variations of cell morphologies. Overall, we demonstrated that the automation of the fast filtration method significantly reduces the time for filtration and quenching and hence enlarge the number of metabolites that can be quantified with this leakage‐free sampling method.
A Spectrophotometric Study of Trivalent Actinide Complexes in Solution.: I. Uranium
Authors: Shiloh M. , Marcus Y.
Published: November 2013

Spectra of uranium (III) were obtained in sulfuric acid and lithium chloride and bromide solutions. Intense hands at 18380 and 18280 cm−1 for concentrated chloride and bromide solutions, respectively, are attributed to 5f‐6d transitions due to the UX2+ species. The stability constant of this complex, or contact‐ion‐pair, has been calculated, β1 = (1.3 ± 0.3)10−3 M−1 for chloride and (1.1 ± 0.2)10−4 M−1 for bromide. These values for the stability constants are much lower than those obtained by other methods for the solvent‐shared‐ion‐pair.
The Determination of Sulfur in Cellulosic Fabrics
Authors: Wasserman T. , Basch A.
Published: November 2013

An improved wet combustion procedure for the determination of sulphur in cellulosic fabrics was developed. The method, which consists of replacing the nitric acid normally used, by hydrochloric acid, yields improved recovery of the sulfur and good precision in the classical gravimetric determination of barium sulfate. Phosphorus and aluminium when present in these fabrics do not interfere.
Kinetics of Fluorescence Quenching by Electron and H‐Atom Transfer
Authors: Rehm Dieter , Weller Albert
Published: November 2013

Fluorescence quenching rate constants, kq, ranging from 106 to 2 × 1010 M−1 sec−1, of more than 60 typical electron donor‐acceptor systems have been measured in de‐oxygenated acetonitrile and are shown to be correlated with the free enthalpy change, ΔG23, involved in the actual electron transfer process

magnified image

in the encounter complex and varying between + 5 and −60 kcal/mole. The correlation which is based on the mechanism of adiabatic outer‐sphere electron transfer requires ΔG≠23, the activation free enthalpy of this process to be a monotonous function of ΔG23 and allows the calculation of rate constants of electron transfer quenching from spectroscopic and electrochemical data.

A detailed study of some systems where the calculated quenching constants differ from the experimental ones by several orders of magnitude revealed that the quenching mechanism operative in these cases was hydrogen‐atom rather than electron transfer.

The conditions under which these different mechanisms apply and their consequences are discussed.
Accumulating advantages, reducing limitations: Multimodal nonlinear imaging in biomedical sciences – The synergy of multiple contrast mechanisms
Authors: Meyer Tobias , Schmitt Michael , Dietzek Benjamin , Popp Jürgen
Published: November 2013

Multimodal nonlinear microscopy has matured during the past decades to one of the key imaging modalities in life science and biomedicine due to its unique capabilities of label‐free visualization of tissue structure and chemical composition, high depth penetration, intrinsic 3D sectioning, diffraction limited resolution and low phototoxicity. This review briefly summarizes first recent advances in the field regarding the methodology, e.g., contrast mechanisms and signal characteristics used for contrast generation as well as novel image processing approaches. The second part deals with technologic developments emphasizing improvements in penetration depth, imaging speed, spatial resolution and nonlinear labeling strategies. The third part focuses on recent applications in life science fundamental research and biomedical diagnostics as well as future clinical applications. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The deduced evolution history of Omsk hemorrhagic fever virus
Authors: Karan Liudmila S. , Ciccozzi Massimo , Yakimenko Valerii V. , Presti Alessandra Lo , Cella Eleonora , Zehender Gianguglielmo , Rezza Giovanni , Platonov Alexander E.
Published: November 2013

Omsk hemorrhagic fever (OHF) is a severe disease that emerged in the 1940s in Siberia, Russia. It is caused by the OHF virus (OHFV), belonging to the Flavivirus genus. In wildlife, the principal vector of OHFV is the Dermacentor reticulatus tick. However, humans are mainly infected after contact with an infected muskrat Ondatra zibethicus. The evolutionary history of OHFV is not yet clarified. In an attempt to reconstruct the temporal and spatial phylodynamics of OHFV, a collection of 25 OHFV strains was studied. Maximum likelihood analysis, the Bayesian MCMC approach, and procedures based on continuous‐time Markov Chain process, were used for the investigation of OHFV E gene nucleotide sequences. Six statistically supported clusters of OHFV were identified; five of them joined in a main clade A. The first revealed evolutionary event, when OHFV clade A and clade B divided, dated to about 700 years ago. Clusters C, D, and E, within clade A, separated 230 years ago and further evolved during last century. The phylogeographic analysis showed that clade A originated in the Omsk Province, whereas clusters B, C, and E appeared to originate in Kurgan, Novosibirsk, and Omsk Provinces, respectively. In conclusion, OHFV, as a member of the mammalian tick‐borne group of flaviviruses, evolved in Western Siberia during the last millennium. When a highly susceptible species, O.zibethicus, was introduced into the region, in the 1930s, OHFV used this species as an amplifying host that lead to numerous fatal epizootics in muskrats and to human OHF outbreaks. J. Med. Virol. 86:1181–1187, 2014. © 2013 Wiley Periodicals, Inc.
Compensation of signal loss due to cardiac motion in point‐resolved spectroscopy of the heart
Authors: Weiss Kilian , Summermatter Severin , Stoeck Christian T. , Kozerke Sebastian
Published: November 2013

Purpose

To study the influence of cardiac motion on point‐resolved single voxel spectroscopy (PRESS) of the human heart and to propose an improved sequence design to compensate for cardiac motion–related signal losses.

Methods

Numerical simulations and in vivo measurements were performed to study motion effects in cardiac spectroscopy. Based on the findings, an improved PRESS sequence with reduced free induction decay spoiling areas was implemented. Myocardial triglyceride (TG) content as estimated with the improved PRESS sequence was compared with the default PRESS sequence commonly used for spectroscopy in nonmoving tissues that was provided by the manufacturer.

Results

Numerical simulations and in vivo data show the importance of optimal trigger delays to avoid signal losses in cardiac spectroscopy. The improved PRESS sequence was found to yield a significantly reduced sensitivity to cardiac motion and trigger delay setting and provided a 1.7‐fold increase in signal‐to‐noise ratio on average compared with the default PRESS sequence. Intrasubject variation of myocardial TG content was reduced with the improved sequence compared with the default PRESS sequence (coefficient of variation: 0.11 ± 0.03 versus 0.23 ± 0.06).

Conclusion

Improvement of the sequence design is essential to reduce the sensitivity of PRESS to cardiac motion. Magn Reson Med 72:1201–1207, 2014. © 2013 Wiley Periodicals, Inc.
Qualitative and quantitative analysis of the adult Drosophila melanogaster proteome
Authors: Xing Xiaohua , Zhang Chengpu , Li Ning , Zhai Linhui , Zhu Yunping , Yang Xiaoming , Xu Ping
Published: November 2013

Drosophila melanogaster is one of the most widely used model organisms in life sciences. Mapping its proteome is of great significance for understanding the biological characteristics and tissue functions of this species. However, the comprehensive coverage of its proteome remains a challenge. Here, we describe a high‐coverage analysis of whole fly through a 1D gel electrophoresis and LC‐MS/MS approach. By combining the datasets of two types of SDS‐PAGE and two kinds of tagmata, the high‐coverage analysis resulted in the identification of 5262 genes, which correspond to 38.23% of the entire coding genes. Moreover, we found that the fly head and body have different molecular weight distributions of their proteomes when the proteins were resolved with SDS‐PAGE and image analysis of the stained gel. This phenomenon was further confirmed by both label‐free and isobaric tags for relative and absolute quantitation‐based quantitative approaches. The consistent results of the two different quantitation methods also demonstrated the stability and accuracy of the LC‐MS/MS platform. The MS proteomics data have been deposited to the ProteomeXchange with identifiers PXD000454 and PXD000455 (http://proteomecentral.proteomexchange.org/dataset/PXD000454; (http://proteomecentral.proteomexchange.org/dataset/PXD000455).
Single‐step protease cleavage elution for identification of protein–protein interactions from GST pull‐down and mass spectrometry
Authors: Luo Lin , King Nathan P. , Yeo Jeremy C. , Jones Alun , Stow Jennifer L.
Published: November 2013

The study of protein–protein interactions is a major theme in biological disciplines. Pull‐down or affinity‐precipitation assays using GST fusion proteins have become one of the most common and valuable approaches to identify novel binding partners for proteins of interest (bait). Non‐specific binding of prey proteins to the beads or to GST itself, however, inevitably complicates and impedes subsequent analysis of pull‐down results. A variety of measures, each with inherent advantages and limitations, can minimise the extent of the background. This technical brief details and tests a modification of established GST pull‐down protocols. By specifically eluting only the bait (minus the GST tag) and the associated non‐specific binding proteins with a simple, single‐step protease cleavage, a cleaner platform for downstream protein identification with MS is established. We present a proof of concept for this method, as evidenced by a GST pull‐down/MS case study of the small guanosine triphosphatase (GTPase) Rab31 in which: (i) sensitivity was enhanced, (ii) a reduced level of background was observed, (iii) distinguishability of non‐specific contaminant proteins from genuine binders was improved and (iv) a putative new protein–protein interaction was discovered. Our protease cleavage step is readily applicable to all further affinity tag pull‐downs.
Modulation of Melanin Synthesis by Rengyolone Isolated from the Root of Eurya emarginata in Melan‐a Cells
Authors: Kim Jin Hee , Jeong Sang Chul , Hwang Jae Sung , Lee Eun Sook , Lee Sang Myung
Published: November 2013

In the course of screening for the melanogenesis inhibitors, rengyolone was isolated from Eurya emarginata (Thumb) Makino. Its chemical structure was determined on the basis of spectroscopic analysis including mass spectroscopy and nuclear magnetic resonance analysis. Rengyolone inhibited potent melanogenesis in melan‐a cells with an IC50 value of 65 μM without cytotoxicity. Also, rengyolone showed a melanin biosynthesis inhibition zone in a culture plate of Streptomyces bikiniensis, which is commonly used as an indicator organism. Moreover, rengyolone dramatically reduced protein expression of melanogenic enzyme, tyrosinase. Furthermore, rengyolone presented inhibition on the body pigmentation in zebrafish model system and decreased melanin contents and tyrosinase activity. These results suggest that rengyolone isolated from E. emarginata may be an effective skin‐whitening agent that regulates the expression of melanogenic enzymes. Copyright © 2013 John Wiley & Sons, Ltd.
Effect of sulfolane on the morphology and chemical composition of the solid electrolyte interphase layer in lithium bis(oxalato)borate‐based electrolyte
Authors: Yu Tao , Liu Jinliang , Zhang Hongming , Li Shiyou , Cui Xiaoling , Feng Huixia , Zhao Yangyu , Liu Haining , Li Faqiang
Published: November 2013

To discuss the source of sulfolane (SL) in decreasing the interface resistance of Li/mesophase carbon microbeads cell with lithium bis(oxalate)borate (LiBOB)‐based electrolyte, the morphology and the composition of the solid electrolyte interphase (SEI) layer on the surface of carbonaceous anode material have been investigated. Compared with the cell with 0.7 mol l−1 LiBOB‐ethylene carbonate/ethyl methyl carbonate (EMC) (1 : 1, v/v) electrolyte, the cell with 0.7 mol l−1 LiBOB‐SL/EMC (1 : 1, v/v) electrolyte shows better film‐forming characteristics in SEM (SEI) spectra. According to the results obtained from Fourier transform infrared spectroscopy, XPS, and density functional theory calculations, SL is reduced to Li2SO3 and LiO2S(CH2)8SO2Li through electrochemical processes, which happens prior to the reduction of either ethylene carbonate or EMC. It is believed that the root of impedance reduction benefits from the rich existence of sulfurous compounds in SEI layer, which are better conductors of Li+ ions than analogical carbonates. Copyright © 2013 John Wiley & Sons, Ltd.
ASR FORUM: ENGAGING WITH AFRICAN INFORMAL ECONOMIES
Authors: Prag Ebbe
Published: November 2013

This article examines the impact of Chinese textile imports on the organization and politics of women’s textile trading networks in Benin. The incursion of cheap Chinese textiles into markets formerly dominated by imported European fabrics has shifted the balance of power between networks of traders in Benin’s textile market, reconfiguring relations between textile traders, state officials, and international companies. Focusing on political and economic dimensions of trading networks, the article reveals how global linkages transform local economic networks and how local actors structure networks for global economic partners. Far from bypassing state actors, this process is shown to incorporate state officials from above and from below, splintering established trading networks and weaving new ones from emerging configurations of traders, state officials, and global textile exporters.
THE GROTHENDIECK CONSTANT IS STRICTLY SMALLER THAN KRIVINE’S BOUND
Authors: BRAVERMAN MARK , MAKARYCHEV KONSTANTIN , MAKARYCHEV YURY , NAOR ASSAF
Published: November 2013

The (real) Grothendieck constant ${K}_{G} $ is the infimum over those $K\in (0, \infty )$ such that for every $m, n\in \mathbb{N} $ and every $m\times n$ real matrix $({a}_{ij} )$ we have $$\begin{eqnarray*}\displaystyle \max _{\{ x_{i}\} _{i= 1}^{m} , \{ {y}_{j} \} _{j= 1}^{n} \subseteq {S}^{n+ m- 1} }\sum _{i= 1}^{m} \sum _{j= 1}^{n} {a}_{ij} \langle {x}_{i} , {y}_{j} \rangle \leqslant K\max _{\{ \varepsilon _{i}\} _{i= 1}^{m} , \{ {\delta }_{j} \} _{j= 1}^{n} \subseteq \{ - 1, 1\} }\sum _{i= 1}^{m} \sum _{j= 1}^{n} {a}_{ij} {\varepsilon }_{i} {\delta }_{j} . &&\displaystyle\end{eqnarray*}$$ The classical Grothendieck inequality asserts the nonobvious fact that the above inequality does hold true for some $K\in (0, \infty )$ that is independent of $m, n$ and $({a}_{ij} )$. Since Grothendieck’s 1953 discovery of this powerful theorem, it has found numerous applications in a variety of areas, but, despite attracting a lot of attention, the exact value of the Grothendieck constant ${K}_{G} $ remains a mystery. The last progress on this problem was in 1977, when Krivine proved that ${K}_{G} \leqslant \pi / 2\log (1+ \sqrt{2} )$ and conjectured that his bound is optimal. Krivine’s conjecture has been restated repeatedly since 1977, resulting in focusing the subsequent research on the search for examples of matrices $({a}_{ij} )$ which exhibit (asymptotically, as $m, n\rightarrow \infty $) a lower bound on ${K}_{G} $ that matches Krivine’s bound. Here, we obtain an improved Grothendieck inequality that holds for all matrices $({a}_{ij} )$ and yields a bound ${K}_{G} \lt \pi / 2\log (1+ \sqrt{2} )- {\varepsilon }_{0} $ for some effective constant ${\varepsilon }_{0} \gt 0$. Other than disproving Krivine’s conjecture, and along the way also disproving an intermediate conjecture of König that was made in 2000 as a step towards Krivine’s conjecture, our main contribution is conceptual: despite dealing with a binary rounding problem, random two-dimensional projections, when combined with a careful partition of ${ \mathbb{R} }^{2} $ in order to round the projected vectors to values in $\{ - 1, 1\} $, perform better than the ubiquitous random hyperplane technique. By establishing the usefulness of higher-dimensional rounding schemes, this fact has consequences in approximation algorithms. Specifically, it yields the best known polynomial-time approximation algorithm for the Frieze–Kannan Cut Norm problem, a generic and well-studied optimization problem with many applications.
Steady one-dimensional nozzle flow solutions of liquid–gas mixtures
Authors: LeMartelot S. , Saurel R. , Le Métayer O.
Published: November 2013

Exact compressible one-dimensional nozzle flow solutions at steady state are determined in various limit situations of two-phase liquid–gas mixtures. First, the exact solution for a pure liquid nozzle flow is determined in the context of fluids governed by the compressible Euler equations and the ‘stiffened gas’ equation of state. It is an extension of the well-known ideal-gas steady nozzle flow solution. Various two-phase flow models are then addressed, all corresponding to limit situations of partial equilibrium among the phases. The first limit situation corresponds to the two-phase flow model of Kapilaet al. (Phys. Fluids, vol. 13, 2001, pp. 3002–3024), where both phases evolve in mechanical equilibrium only. This model contains two entropies, two temperatures and non-conventional shock relations. The second one corresponds to a two-phase model where the phases evolve in both mechanical and thermal equilibrium. The last one corresponds to a model describing a liquid–vapour mixture in thermodynamic equilibrium. They all correspond to two-phase mixtures where the various relaxation effects are either stiff or absent. In all instances, the various flow regimes (subsonic, subsonic–supersonic, and supersonic with shock) are unambiguously determined, as well as various nozzle solution profiles.
Treatment with citalopram, but not with agomelatine, adversely affects sperm parameters: a case report and translational review
Authors: Elnazer Hesham Y. , Baldwin David S.
Published: November 2013

Background

Adverse effects of antidepressant drug treatmenton sexual function are well documented but the effects of antidepressants on sperm production have not been researched extensively.

Methods

A narrative of an interventional case report of sperm parameters in a 30-year-old Caucasian man with a diagnosis of mixed depressive and anxiety disorder, who underwent citalopram treatment, followed by agomelatine treatment. Clinical observations prompted a review of the pre-clinical and clinical literature on the effects of antidepressant administration or treatment on sperm production and parameters. Findings from the review are discussed to suggest potential underlying mechanisms.

Results

Abnormal sperm parameters were associated with treatment with the SSRI citalopram. There was an improvement in sperm concentration, motility, progressive motility and sperm morphology following its withdrawal. There was no similar association during subsequent treatment with agomelatine. The clinical observations reflect findings from animal studies, which indicate that antidepressants can have untoward effects on spermatogenesis.

Conclusions

SSRI treatment can be associated with impaired semen quality. Potential underlying mechanisms include changes in sperm DNA integrity, activation of IDO and shifting tryptophan metabolism. Further studies of the effects of antidepressants on spermatogenesis might benefit from including investigation of changes in IDO activity during antidepressant administration.
Policy reform of emission taxes and environmental research and development incentives in an international Cournot model with product differentiation
Authors: Gautier Luis
Published: November 2013

This paper studies multilateral and unilateral policy reforms of environmental R&D subsidies and emission taxes in a two-country Cournot model with oligopolistic interdependence. The analysis indicates, inter alia, that there is a potential family of multilateral and unilateral policy reforms which can be set by pollution-intensive and pollution-moderate countries to reduce global emissions. In particular, the analysis suggests that a unilateral increase in the subsidy in the pollution-moderate country may reduce global emissions. The multilateral policy reform of the subsidy and tax in the pollution-intensive country can also reduce global emissions and increase welfare under certain conditions. The role of product differentiation in the context of policy reform is also examined.
Integrated sorting, concentration and real time PCR based detection system for sensitive detection of microorganisms
Authors: Nayak Monalisha , Singh Deepak , Singh Himanshu , Kant Rishi , Gupta Ankur , Pandey Shashank Shekhar , Mandal Swarnasri , Ramanathan Gurunath , Bhattacharya Shantanu
Published: November 2013

The extremely low limit of detection (LOD) posed by global food and water safety standards necessitates the need to perform a rapid process of integrated detection with high specificity, sensitivity and repeatability. The work reported in this article shows a microchip platform which carries out an ensemble of protocols which are otherwise carried in a molecular biology laboratory to achieve the global safety standards. The various steps in the microchip include pre-concentration of specific microorganisms from samples and a highly specific real time molecular identification utilizing a q-PCR process. The microchip process utilizes a high sensitivity antibody based recognition and an electric field mediated capture enabling an overall low LOD. The whole process of counting, sorting and molecular identification is performed in less than 4 hours for highly dilute samples.
Continuous flow real-time PCR device using multi-channel fluorescence excitation and detection
Authors: Hatch Andrew C. , Ray Tathagata , Lintecum Kelly , Youngbull Cody
Published: November 2013

We have developed a ‘conveyor belt’ analog for real-time quantitative polymerase chain reaction (qPCR) in a continuous flow thermocycler. The device integrates droplet emulsion technology with LED and fiber optic fluorescence excitation in conjunction with a continuous flow thermal cycler to achieve real-time fluorescence detection.