bluuebunny/crossref_metadata_2025 huggingface dataset:
Trennung von Salzlösungen mittels Hochtemperaturelektrodialyse
Authors: Behret H. , Binder H. , Eggersdorfer R. , Hampel H. J. , Köhling A.
Published: September 2012

Elektrodialyseanlagen werden heute für eine Vielzahl von Stofftrennungen, wie beispielsweise zur Meer‐ und Brackwasserentsalzung und zur Aufbereitung industrieller Prozeß‐ und Abwässer eingesetzt. Da wesentliche Verfahrensparameter temperaturabhängig sind, können durch Temperaturerhöhung die Anlagen‐ und/oder Betriebskosten gesenkt werden. Es wurden sowohl physikalisch‐chemische Membrandaten als auch Verfahrensparameter bestimmt. — Bei der elektrodialytischen Meerwasserentsalzung kann durch Erhöhung der Temperatur von 25°C auf 75°C der Membranbedarf um etwa 60% verringert und damit eine Senkung der Wasserkosten um 33% erreicht werden. — Für die Trennung von Ammoniumsulfat in Ammoniak und Schwefelsäure wurde im Gegensatz zu den üblicherweise benutzten H2‐entwickelnden Kathoden eine luftdepolarisierte Elektrode eingesetzt. Die dadurch erzielte Energieeinsparung betrug bei 25°C etwa 15 bis 20% und stieg bei Erhöhung der Betriebstemperatur auf 50°C auf etwa 25% an.
Adsorption of Weak Organic Electrolytes from Aqueous Solution on Activated Carbon. ‐ Effect of pH
Authors: Müller G. , Radke C. R. , Prausnitz J. M.
Published: September 2012

Es wird ein physikalisches Modell vorgestellt, um den pH‐Effekt auf das Adsorptionsgleichgewicht schwacher, organischer Säuren oder Basen von verdünnter, wäßriger Lösung an Aktivkohle vorauszuberechnen. Die Oberflächen‐Heterogenität des Adsorbens wird durch das Modell homogener Oberflächenausschnitte (patch‐model) und einer exponentiellen Verteilung der Adsorptionsenergie beschrieben. Die konkurrierende Adsorption dissoziierter und molekularer Sorptivteilchen auf jedem homogenen Oberflächenausschnitt wird mit einer lokalen Langmuir‐Isotherme beschrieben; die ladungsunabhängigen Parameter sind hierbei identisch für beide Teilchenarten. Die Adsorbensoberfläche trägt elektrostatische Ladung entsprechend dem Lösungs‐pH und der Ionenstärke; das resultierende (verschmierte) elektrostatische Oberflächenpotential beeinflußt die Affinität des ionogenen Sorptivs zur Oberfläche. Die Oberflächenladung bei verschiedenen Lösungs‐pH wird durch Titration der Oberfläche mit starken Säuren und Basen ermittelt.

Für bestimmte Kombinationen von Sorptiv‐pK, Sorptivkonzentration sowie der Oberflächenladung wird ein Adsorptionsmaximum mit der Wasserstoffionen‐Konzentration erhalten. Für homogene Oberflächen und kleine Oberflächenbedeckungen folgt der Bedeckungsverlauf bei pH‐Änderungen der Dissoziationskurve des Sorptivs.

Neue experimentelle Adsorptionsisothermen, bei verschiedenen pH, werden für Benzoesäure und p‐Nitrophenol mitgeteilt. Über einen großen pH‐Bereich wird eine gute Übereinstimmung zwischen berechneten und gemessenen Gleichgewichtswerten erzielt.
Chromatographic Study of Mixed Gas Adsorption by the Step and Pulse Method
Authors: Von Rybinski W. , Findenegg G. H.
Published: September 2012

The step‐and‐pulse method is used to study the influence of preadsorption of a vapor on the retention of small samples of other vapors. This paper outlines the relevant theoretical relations and the experimental technique used by us. Some results concerning the simultaneous adsorption of isomeric C6 hydrocarbons on graphitized carbon black are presented. The significance of the results for the separation of these substances by gas adsorption chromatography is discussed briefly.
Bestimmung von kathodischen H/D‐Trennfaktoren an Au und Hg in saurer Lösung
Authors: Grambow L. , Heitbaum J.
Published: September 2012

Massenspektroskopische Messungen des kathodischen H/D‐Trennfaktors an Au und Hg bei gleichzeitiger Aufnahme der Stromspannungskurven lieferten folgende Ergebnisse:

An Au ist SD = 5,0 unabhängig von der Überspannung im Potentialbereich −40 ≥ η ≥ ‐ 250 mV, obwohl in diesem Bereich eine Änderung der Tafelsteigung von zunächst 34 auf 118 mV/i‐Dekade eintritt.

An Hg wird bei ‐900 ≥ η ≥ ‐1050 mV SD = 5,5 gemessen, bei η ≤ ‐1200 mV ist SD = 3,8. Die Tafelsteigung bleibt mit 120 mV/i‐Dekade konstant.
Anreicherung von Dotierungsstoffen an Pseudophasengrenzen
Authors: Leute Volkmar , Flötotto Burkhard
Published: September 2012

Bei der Chalkogeninterdiffusion zwischen In‐dotiertem HgTe und In‐dotiertem HgSe bei 600 °C läßt sich mit der Elektronenstrahl‐Mikrosonde auf der Selenidseite der Grenzfläche eine In‐Anreicherung und auf der Telluridseite eine In‐Verarmung feststellen. Dieser Anreicherungseffekt erfolgt sehr viel rascher als die Chalkogeninterdiffussion und führt im Anfangsstadium des Diffusionsprozesses an der Stelle der ursprünglichen Grenzfläche zwischen Selenid‐ und Telluridbereich zu einem relativ scharfen Konzentrationssprung, der sich im weiteren Verlauf abflacht und verbreitert. Da HgTe und HgSe eine lückenlose Legierungsreihe bilden und die In‐Löslichkeit in diesen Experimenten noch längst nicht erreicht ist, ist es sehr unwahrscheinlich, daß der beobachtete Effekt durch eine Abweichung der Mischphase vom idealen Verhalten erklärt werden kann. Der Effekt wird verständlich, wenn man annimmt, daß bei gegebener Legierungszusammensetzung sich die Wahrscheinlichkeiten dafür, daß Selenatome bzw. Telluratome ins Zwischengitter gehen, wesentlich voneinander unterscheiden und daß der In‐Austausch, der über Hg‐Leerstellen verlaufen soll, an der Pseudophasengrenze zwischen Selenid‐ und Telluridbereich sich im lokalen thermodynamischen Gleichgewicht befindet.
Metallionenextraktion
Authors: Nitsch W.
Published: September 2012

An Beispielen aus dem eigenen Arbeitskreis wird ein Überblick gegeben über die Kinetik der Metallionenextraktion. Ausführlich behandelt wird die Überlagerung strömungsabhängiger Transportprozesse mit Grenzflächenreaktionen, die Aufstellung der zuständigen Modelle und deren experimentelle Überprüfung. Am Beispiel der gekoppelten Stoffübertragung von Salpetersäure und Uranylkationen in eine Tributylphosphat‐beladene Hexanphase wird das für mehrkomponentige Systeme typische Problem des Zuganges zu den Transport‐koeffizienten angeschnitten. Am gleichen System wird gezeigt, daß das kinetische Systemverhalten wegen der Anzahl der Gleichungen und deren Kopplung nur über numerische Verfahren beurteilt werden kann. Abschließend behandelt wird die Wirkung von Adsorptions‐schichten auf die Massenflüsse zwischen Flüssigphasen. Hingewiesen wird auf die entscheidenden Unterschiede, die sich bei einer Transportkinetik respektive einer Grenzflächenkinetik ergeben: Sind Transportprozesse geschwindigkeitsbestimmend, so bewirken Adsorbate eine Dämpfung der Strömung und damit der Transportkoeffizienten, im Falle einer Grenzflächenkinetik ist die Adsorbatwirkung eine Katalyse.
Über den Einfluß von Phasenverteilungen auf den Wirkungsgrad von Trennstufen
Authors: Schlünder E. U.
Published: September 2012

Trennstufen, deren Wirkung auf dem Ausgleich von Gleichgewichtsstörungen beruhen, erreichen ihre maximale Trennleistung, wenn dieser Ausgleich vollständig abläuft. Tatsächlich beobachtet man stets einen unvollständigen Ausgleich. Als Ursache hierfür wird die endliche Diffusionsgeschwindigkeit der Komponenten in den beteiligten Phasen angesehen. ‐ Es wird gezeigt, daß ein unvollständiger Ausgleich auch allein durch eine mikroskopische Fehlordnung der beteiligten Phasen verursacht werden kann, ohne daß dabei die Gesetze der Diffusion eine Rolle spielen. Die Existenz solcher Fehlordnungen wird durch eine Analyse von Meßwerten an Füllkörperstufen nachgewiesen. ‐ Für weitere Nachweise dieser Art wird ein hierfür besonders geeignetes Experiment vorgeschlagen.
Zur Verwendung von Na‐Al‐Silikaten in Waschmitteln Teil VIII: Farbstoffgleichgewichte in Mehrkomponentensystemen
Authors: Nüßlein H. , Schumann K. , Schwuger M. J.
Published: September 2012

Hauptbestandteile des Wäscheschmutzes bilden ölige und fettige Anschmutzungen, Pigmente sowie lösliche und unlösliche Salze. Farbstoffe als Schmutz nehmen eine Sonderstellung speziell in industriellen Waschprozessen ein. Am Beispiel eines Substantivfarbstoffs wurde die Beeinflussung von Farbstoffgleichgewichten in Waschprozessen durch das klassische lösliche Hilfsmittel Polyvinylpyrrolidon (PVP) und die wasserunlösliche Wirksubstanz Na — Al‐Silikat (SASIL) untersucht. Während PVP im wäßrigen Medium den Farbstoff durch Komplexbildung stabilisiert, verhindert SASIL durch gezielte Abgabe von löslichen Bestandteilen, die mit Farbstoffen und Fasern in Wechselwirkung treten können, das Wiederaufziehen der Farbstoffe auf textile Oberflächen. Kolloidchemische Untersuchungen in Verbindung mit Modellwaschversuchen zeigen, daß beide Substanzen, trotz unterschiedlicher Wirkmechanismen, einen vergleichbaren Einfluß auf die Farbstoffgleichgewichte im wäßrigen Medium ausüben.
Temperature‐dependent hyperfine coupling constants. An ESR study of the N‐hydropyridinyl radical in solution
Authors: Sander Ulrich , Dohrmann Jürgen K.
Published: September 2012

The proton and nitrogen hyperfine splittings of the short‐lived N‐hydropyridinyl radical have been measured over the temperature range ‐80 to 42°C in Propanol(‐2)/Acetone. The ESR‐data of the N‐deuteropyridinyl and the N‐hydropentadeuteropyridinyl radical at 22°C have been determined. The temperature coefficient of the NH proton splitting and the shift in the splitting caused by N‐deuterium substitution are unusually large. The effects of temperature and deuterium substitution have been analyzed using the model of localized out‐of‐plane vibrations of the protons. The estimated frequencies, in units of cm−1, are 290, 490, and 870 for the protons in position 1, 3(5), and 4, respectively. The result is discussed in connection with other ESR and MO studies on N‐hydropyridinyl and N, N′‐dihydrodiazinyl radicals. The previously observed non‐transferability of the spin polarization parameter QHNH is explained by the exceptionally low vibration frequency of the NH proton. A value of QHNH = −3.1 ± 0.4 mT is derived for the fixed planar structure of the radical. The vibrational analysis also confirms the negative sign of the π‐spin density on the carbon atoms in position 3 and 5.
Pressure and temperature dependence of the longitudinal proton and deuteron relaxation rates in NH3 and ND3
Authors: Hauer H. , Lang E. , Lüdemann H.‐D.
Published: September 2012

The molecular mobility of liquid ammonia is derived from the determination of the longitudinal relaxation times of the protons and deuterons. The experiments were performed in the temperature interval between the melting pressure curve and 467 K for NH3 and to 351 K for ND3 at pressures up to 250 MPa. At temperatures below ∼ 350 K the molecular mobility can be described by the isotropic small‐step diffusion model. The activation energies at constant pressure are derived for the rotatoric diffusion to 7.0 ± 0.5 kJ · mol−1 and for the translatoric diffusion to 6 ± 1 kJ · mol−1 from the temperature dependence of the relaxation rates. In addition the activation energy at constant volume for the rotatoric diffusion has been determined to 5.7 ± 0.5 kJ · mol−1. The isotherms for all relaxation rates are linear in a log(1/T1) versus 1/T plot, yielding ΔV≠intra = 2.5 ± 0.6 cm3 · mol−1 and ΔV≠inter = 5 ± 1 cm3 · mol−1.
Identification of the gaseous molecules ZnS(g), ZnTe(g), CdTe(g), and HgSe(g) in equilibrium with the solid phase
Authors: Grade M. , Hirschwald W.
Published: September 2012

By means of high‐temperature mass‐spectrometry the gaseous IIB/VIA‐molecules ZnS(g), ZnTe(g), CdTe(g), and HgSe(g) were identified by their isotopic distributions in equilibrium with the corresponding solid chalcogenides. HgTe(g) remains the only MeX(g)‐molecule of the IIB/VIA‐type as yet undetected — suggesting that the remaining eleven IIB/VIA‐molecules may originate from a gas‐phase reaction between Me(g)‐ and Xi(g)‐species which cannot occur in the HgTe‐system due to the absence of gaseous Tei in the equilibrium vapor phase.
Numerical assessment of the performance of a scalp‐implantable antenna: Effects of head anatomy and dielectric parameters
Authors: Kiourti Asimina , Nikita Konstantina S.
Published: September 2012

We numerically assess the effects of head properties (anatomy and dielectric parameters) on the performance of a scalp‐implantable antenna for telemetry in the Medical Implant Communications Service band (402.0–405.0 MHz). Safety issues and performance (resonance, radiation) are analyzed for an experimentally validated implantable antenna (volume of 203.6 mm3), considering five head models (3‐ and 5‐layer spherical, 6‐, 10‐, and 13‐tissue anatomical) and seven scenarios (variations ± 20% in the reference permittivity and conductivity values). Simulations are carried out at 403.5 MHz using the finite‐difference time‐domain method. Anatomy of the head model around the implantation site is found to mainly affect antenna performance, whereas overall tissue anatomy and dielectric parameters are less significant. Compared to the reference dielectric parameter scenario within the 3‐layer spherical head, maximum variations of −19.9%, +3.7%, −55.1%, and −39.2% are computed in the maximum allowable net input power imposed by the IEEE Std C95.1‐1999 and Std C95.1‐2005 safety guidelines, return loss, and maximum far‐field gain, respectively. Compliance with the recent IEEE Std C95.1‐2005 is found to be almost insensitive to head properties, in contrast with IEEE Std C95.1‐1999. Taking tissue property uncertainties into account is highlighted as crucial for implantable antenna design and performance assessment. Bioelectromagnetics 34:167–179, 2013. © 2012 Wiley Periodicals, Inc.
Luminometer development in the last four decades: recollections of two entrepreneurs
Authors: Berthold Fritz , Tarkkanen Veikko
Published: September 2012

This article, written by two entrepreneurs in luminescence, traces their involvement in the major part of the interconnected innovation and development of luminometers, adenosine triphosphate (ATP) bioluminescence and other technologies from the mid‐1970s to 2011 that ushered in much of the field of luminometry as we know it today. Key developments leading to current commercial applications of ATP bioluminescence, luminescence immunoassay, cellular luminescence, reporter gene and other applications are described from the first tube luminometers derived from early luminescence studies using liquid scintillation counting technology to measuring bioluminescence from crude ATP and firefly tail extracts. Copyright © 2012 John Wiley & Sons, Ltd.
Surface functionalization of carbon nanomaterials by self‐assembling hydrophobin proteins
Authors: Yang Wenrong , Ren Qin , Wu Ya‐Na , Morris Vanessa K. , Rey Anthony A. , Braet Filip , Kwan Ann H. , Sunde Margaret
Published: September 2012

Class I fungal hydrophobins are small surface‐active proteins that self‐assemble to form amphipathic monolayers composed of amyloid‐like rodlets. The monolayers are extremely robust and can adsorb onto both hydrophobic and hydrophilic surfaces to reverse their wettability. This adherence is particularly strong for hydrophobic materials. In this report, we show that the class I hydrophobins EAS and HYD3 can self‐assemble to form a single‐molecule thick coating on a range of nanomaterials, including single‐walled carbon nanotubes (SWCNTs), graphene sheets, highly oriented pyrolytic graphite, and mica. Moreover, coating by class I hydrophobin results in a stable, dispersed preparation of SWCNTs in aqueous solutions. No cytotoxicity is detected when hydrophobin or hydrophobin‐coated SWCNTs are incubated with Caco‐2 cells in vitro. In addition, we are able to specifically introduce covalently linked chemical moieties to the hydrophilic side of the rodlet monolayer. Hence, class I hydrophobins provide a simple and effective strategy for controlling the surfaces of a range of materials at a molecular level and exhibit strong potential for biomedical applications. © 2012 Wiley Periodicals, Inc.
A 3D cell culture system: Separation distance between INS‐1 cell and endothelial cell monolayers co‐cultured in fibrin influences INS‐1 cells insulin secretion
Authors: Sabra Georges , Vermette Patrick
Published: September 2012

The aim of this study was to develop an in vitro cell culture system allowing studying the effect of separation distance between monolayers of rat insulinoma cells (INS‐1) and human umbilical vein endothelial cells (HUVEC) co‐cultured in fibrin over INS‐1 cell insulin secretion. For this purpose, a three‐dimensional (3D) cell culture chamber was designed, built using micro‐fabrication techniques and validated. The co‐culture was successfully carried out and the effect on INS‐1 cell insulin secretion was investigated. After 48 and 72 h, INS‐1 cells co‐cultured with HUVEC separated by a distance of 100 µm revealed enhanced insulin secretion compared to INS‐1 cells cultured alone or co‐cultured with HUVEC monolayers separated by a distance of 200 µm. These results illustrate the importance of the separation distance between two cell niches for cell culture design and the possibility to further enhance the endocrine function of beta cells when this factor is considered. Biotechnol. Bioeng. 2013; 110: 619–627. © 2012 Wiley Periodicals, Inc.
High density continuous production of murine pluripotent cells in an acoustic perfused bioreactor at different oxygen concentrations
Authors: Baptista Ricardo P. , Fluri David A. , Zandstra Peter W.
Published: September 2012

Strategies for the production of pluripotent stem cells (PSCs) rely on serially dissociated adherent or aggregate‐based culture, consequently limiting robust scale‐up of cell production, on‐line control and optimization of culture conditions. We recently developed a method that enables continuous (non‐serially dissociated) suspension culture‐mediated reprogramming to pluripotency. Herein, we use this method to demonstrate the scalable production of PSCs and early derivatives using acoustic filter technology to enable continuous oxygen‐controlled perfusion culture. Cell densities of greater than 1 × 107 cells/mL were achieved after 7 days of expansion at a specific growth rate (µ) of 0.61 ± 0.1 day−1 with a perfusion rate (D) of 5.0 day−1. A twofold increase in maximum cell density (to greater than 2.5 × 107 cells/mL) was achieved when the medium dissolved oxygen was reduced (5% DO). Cell densities and viabilities >80% were maintained for extended production periods during which maintenance of pluripotency was confirmed by stable expression of pluripotency factors (SSEA‐1 and Nanog), as well as the capacity to differentiate into all three germ layers. This work establishes a versatile biotechnological platform for the production of pluripotent cells and derivatives in an integrated, scalable and intensified stirred suspension culture. Biotechnol. Bioeng. 2013; 110: 648–655. © 2012 Wiley Periodicals, Inc.
Anion exchange membrane adsorbers for flow‐through polishing steps: Part I. clearance of minute virus of mice
Authors: Weaver Justin , Husson Scott M. , Murphy Louise , Wickramasinghe S. Ranil
Published: September 2012

Membrane adsorbers may be a viable alternative to the packed‐bed chromatography for clearance of virus, host cell proteins, DNA, and other trace impurities. However, incorporation of membrane adsorbers into manufacturing processes has been slow due to the significant cost associated with obtaining regulatory approval for changes to a manufacturing process. This study has investigated clearance of minute virus of mice (MVM), an 18–22 nm parvovirus recognized by the FDA as a model viral impurity. Virus clearance was obtained using three commercially available anion exchange membrane adsorbers: Sartobind Q®, Mustang Q®, and ChromaSorb®. Unlike earlier studies that have focused on a single or few operating conditions, the aim here was to determine the level of virus clearance under a range of operating conditions that could be encountered in industry. The effects of varying pH, NaCl concentration, flow rate, and other competing anionic species present in the feed were determined. The removal capacity of the Sartobind Q and Mustang Q products, which contain quaternary ammonium based ligands, is sensitive to feed conductivity and pH. At conductivities above about 20 mS/cm, a significant decrease in capacity is observed. The capacity of the ChromaSorb product, which contains primary amine based ligands, is much less affected by ionic strength. However the capacity for binding MVM is significantly reduced in the presence of phosphate ions. These differences may be explained in terms of secondary hydrogen bonding interactions that could occur with primary amine based ligands. Biotechnol. Bioeng. 2013; 110: 491–499. © 2012 Wiley Periodicals, Inc.
Peroxidase immobilized on phospholipid bilayers supported on au (111) by DTT self‐assembled monolayers: Application to dopamine determination
Authors: Fritzen‐Garcia Maurícia B. , Zoldan Vinícius C. , Oliveira Inês Rosane W.Z. , Soldi Valdir , Pasa André A. , Creczynski‐Pasa Tânia B.
Published: September 2012

In this work, horseradish peroxidase (HRP) was immobilized on dimyristoylphosphatidylcholine (DMPC) bilayers supported on Au (111) by dithiotreitol (DTT) self‐assembled monolayers and used as a nanostructured electrochemical biosensor to dopamine determination. The morphology of the phospholipid bilayers and the immobilization of HRP to these layers were characterized by atomic force microscopy (AFM). Square‐wave voltammetry (SWV) experiments were done to investigate the performance of the HRP‐modified electrode. The AFM images indicate that the enzyme is adsorbed at the external layer of the lipid bilayer and, although the electrical charges on the surface were not measured, the enzyme and phospholipids surface interaction occurs probably by electrostatic forces due to the pH used in the experiments. Interestingly, the present system can be used as one‐shot sensor for the rapid detection of dopamine. The analytical performance of this system was linear for dopamine concentrations from 3.3 × 10−5 to 1.3 × 10−3 mol L−1 (r = 0.9997) with a detection limit of 2.0 × 10−6 mol L−1. Our results indicate that the use of HRP‐DMPC bilayer system may be useful not only in developing new nanostructured materials for technological purposes, but could be very useful in fundamental studies to investigate the interactions between different micro‐and macromolecules, even with soluble proteins, and lipid membranes. Biotechnol. Bioeng. 2013; 110: 374–382. © 2012 Wiley Periodicals, Inc.
Enhanced production of Aspergillus niger laccase‐like multicopper oxidases through mRNA optimization of the glucoamylase expression system
Authors: Tamayo‐Ramos Juan Antonio , Barends Sharief , de Lange Dennis , de Jel Annemarie , Verhaert Raymond , de Graaff Leo
Published: September 2012

In filamentous fungi, most of the strategies used for the improvement of protein yields have been based on an increase in the transcript levels of a target gene. Strategies focusing at the translational level have been also described, but are far less explored. Here the 5′ untranslated sequence of the glaA mRNA, a widely used expression system for the expression of recombinant proteins, was modified by the introduction of different nucleotide elements that have positive role in the translation process. Five Aspergillus niger laccase‐like multicopper oxidases (MCOs) coding genes were fused to the native glaA 5′UTR and the three synthetic versions (sUTR1, sUTR2, and sUTR3) as well, and placed under the control of the glucoamylase gene promoter. Afterwards, a total of 20 fungal transformations were done using A. niger N593 as a recipient strain and 50 transformants per transformation were isolated and analyzed. The result of the incorporation of the synthetic 5′UTRs on the overall productivity of the transformants was assessed, on one hand by monitoring the laccase activity of all the isolated transformants, and on the other hand by quantifying and comparing the activity of those secreting the highest level of each MCO. For this purpose, a high‐throughput method for the screening and selection of the best producers was developed. Once the best transformants producing the highest yield of McoA, McoB, McoC, McoD, and McoJ laccases were selected, their production level was quantified in supernatants of liquid cultures. The results obtained in this work indicate that modifications in the native glaA 5′UTR can lead to improvements in protein yields. Biotechnol. Bioeng. 2013; 110: 543–551. © 2012 Wiley Periodicals, Inc.
Rare case of the trunk of the inferior phrenic arteries originating from a common stem with a superior additional left renal artery from the abdominal aorta
Authors: Miclaus Gratian D. , Matusz Petru , Loukas Marios , Ples Horia
Published: September 2012

We describe in this article a rare case of a 39‐year‐old male with an inferior phrenic arteries trunk (IPAaT) originating from a common stem with a superior additional left renal artery (SAdLRA) from the abdominal aorta as revealed by routine multidetector computed tomography angiography. The IPAaT with an endoluminal diameter at the origin of 2.8 mm had an upward path with a total length of 18.4 mm, forking to the right inferior phrenic artery and left inferior phrenic artery. These two arteries had an endoluminal diameter at the origin of 1.7 mm and 2.0 mm, respectively. The presence of the common stem of the IPAaT with a SAdLRA and the length of the IPAaT complicate selective chemoembolization of the liver parenchyma. Clin. Anat. 25:979–982, 2012. © 2012 Wiley Periodicals, Inc.
Investigation of the possible protective role of gallic acid on paraoxanase and arylesterase activities in livers of rats with acute alcohol intoxication
Authors: Kartkaya Kazim , Oğlakçı Ayşegül , Şentürk Hakan , Bayramoğlu Gökhan , Canbek Mediha , Kanbak Güngör
Published: September 2012

Gallic acid, a polyphenyl class natural product from gallnut and green tea, is known to be antioxidant, anti‐inflammatory and radical scavenger. In this study, we aimed to investigate the possible protective effects of gallic acid on paraoxonase and arylesterase activities in liver exposed to acute alcohol intoxication. Paraoxonase and arylesterase activities in liver tissue and serum aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels were measured. Histological investigations were also made. In our study, we observed a significant increase of serum alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities, which are indicators of liver damage after acute ethanol consumption. Gallic acid therapy has significantly reduced the increase in these biomarkers, indicating a possible hepatoprotective effect of gallic acid. Ethanol consumption caused a significant decrease in liver paraoxonase activity (P < 0.001). Gallic acid treatment partly restored this decreased paraoxonase activity, which resulted from ethanol administration. A gallic acid dose of 100 mg/kg was observed as highest restoring effect for paraoxonase activity (P < 0.05). The activity of arylesterase was decreased in the ethanol group as compared with the control group, but this was not significant. However, 50 mg/kg of gallic acid treatment restored the loss of this activity due to ethanol exposure (P < 0.001). We observed that gallic acid ameliorates the liver damage caused by excessive alcohol consumption in a dose‐dependent way. Our results in this study showed that gallic acid might have a protective effect against alcoholic liver disease. Copyright © 2012 John Wiley & Sons, Ltd.
Microchannel Emulsification Using Stainless‐Steel Chips: Oil Droplet Generation Characteristics
Authors: Kobayashi I. , Wada Y. , Hori Y. , Neves M. A. , Uemura K. , Nakajima M.
Published: September 2012

The first stainless‐steel microchannel (MC) emulsification chips with grooved MC arrays, each consisting of uniform‐sized parallel channels and a terrace, were developed. These chips enabled successful spontaneous‐transformation‐based generation of uniformly sized droplets of soybean oil and silicone oil. As for the influence of the dispersed‐phase velocity in a channel, the critical velocity below which uniform‐sized droplets were obtained from the channels depended on the interfacial tension between two phases. The maximum productivity of uniform‐sized oil droplets for the stainless‐steel MC emulsification chips was estimated to be several milliliters per hour. An adapted capillary number that considers the wettability of the dispersed phase of two different oils could be useful for understanding the flow state of the dispersed phase during droplet generation.
Gas‐Liquid Mass Transfer Characteristics in a Rotating‐Drum Bioreactor
Authors: Zhang Q. , Wang Z. , Wen S. , Liu G. , Wu X. , Cong W.
Published: September 2012

The oxygen volumetric mass transfer coefficient is a key parameter to characterize the performance of aerobic bioreactors. A novel rotating‐drum bioreactor (RDB) fitted with a sparger as proposed in a previous work has demonstrated its excellent gas‐liquid mass transfer performance. To provide primary information on the design and scale‐up of the novel RDB, effects of reactor configuration including the number and width of lifters and operation conditions such as rotational speed, aeration rate, and solid volume fraction on mass transfer performance were systematically investigated in a new medium‐sized RDB. Compared with the stirred bioreactor and traditional RDBs, this new RDB exhibits better mass transfer performance. Taking both operational and reactor configuration parameters into consideration, an empirical correlation to predict the volumetric mass transfer coefficient in this type of RDBs was proposed which is valuable for its design and scale‐up.
Behavior of Pieces of Plastic Sheet in Solid‐Liquid Fluidized Bed with Stirring
Authors: Tatemoto Y. , Michikoshi T. , Higashino T. , Maeda S. , Maeda S. , Bando Y.
Published: September 2012

A solid‐liquid fluidized bed of inert particles can be used to separate pure objects from a mixture. Pieces of plastic sheet were selected as the objects to be separated. To estimate the separation characteristics, the behavior of pieces of plastic sheet in the bed was examined experimentally. Slow stirring was used to improve the fluidization state of the bed. The object size and the volume ratio of objects to inert particles were varied. The use of stirring of the bed was effective in improving the fluidization state of the bed, and the objects, which sank in the bed without stirring, moved from the bottom to the upper portion of the bed at a certain liquid velocity. This liquid velocity increases with decreasing object size, and it also increases as the volume ratio of objects to inert particles in the bed increases. When the volume ratio of objects to inert particles is too high, the objects are distributed throughout the entire bed, regardless of the liquid velocity.
Bromenium‐Catalysed Tandem Ring Opening/Cyclisation of Vinylcyclopropanes and Vinylcyclobutanes: A Metal‐Free [3+2+1]/[4+2+1] Cascade for the Synthesis of Chiral Amidines and Computational Investigation
Authors: Ganesh Venkataraman , Sureshkumar Devarajulu , Chanda Debasree , Chandrasekaran Srinivasan
Published: September 2012

We present a detailed study of a [3+2+1] cascade cyclisation of vinylcyclopropanes (VCP) catalysed by a bromenium species (Brδ+Xδ−) generated in situ, which results in the synthesis of chiral bicyclic amidines in a tandem one‐pot operation. The formation of amidines involves the ring‐opening of VCPs with BrX, followed by a Ritter‐type reaction with chloramine‐T and a tandem cyclisation. The reaction has been further extended to vinylcyclobutane systems and involves a [4+2+1] cascade cyclisation with the same reagents. The versatility of the methodology has been demonstrated by careful choice of VCPs and VCBs to yield bicyclo[4.3.0]‐, ‐[4.3.1]‐ and ‐[4.4.0]amidines in enantiomerically pure form. On the basis of the experimental observations and DFT calculations, a reasonable mechanism has been put forth to account for the formation of the products and the observed stereoselectivity. We propose the existence of a π‐stabilised homoallylic carbocation at the cyclopropane carbon as the reason for high stereoselectivity. DFT studies at B3LYP/6‐311+G** and M06‐2X/6‐31+G* levels of theory in gas‐phase calculations suggest the ring‐opening of VCP is initiated at the π‐complex stage (between the double bond and BrX). This can be clearly perceived from the solution‐phase (acetonitrile) calculations using the polarisable continuum model (PCM) solvation model, from which the extent of the ring opening of VCP was found to be noticeably high. Studies also show that the formation of zero‐bridge bicyclic amidines is favoured over other bridged bicyclic amidines. The energetics of competing reaction pathways is compared to explain the product selectivity.
Comparitive study on facilitated pertraction of succinic acid using TRI‐n‐octylamine without and with 1‐octanol
Authors: Caşcaval Dan , Poştaru Madalina , Galaction Anca‐Irina , Kloetzer Lenuta
Published: September 2012

Succinic acid has been pertracted with TOA using free liquid membranes without or with 1‐octanol. The addition of the alcohol led to the increase of up to 2.8–3 times of the acid's initial and final mass flows. At the same time, the influence of 1‐octanol on the transport capacity of the pertraction system was negative, its addition inducing the accumulation of succinic acid into the liquid membrane. A mathematical model describing the acid accumulation inside the liquid membrane has been developed for pertraction systems without and with 1‐octanol and offers good concordance with the experimental data. © 2012 Canadian Society for Chemical Engineering
Effect of annealing on the properties of chemical bath deposited nanorods of CdSe thin films
Authors: Bakiyaraj G. , Dhanasekaran R.
Published: September 2012

Cadmium selenide (CdSe) thin films have been deposited by chemical bath deposition (CBD) on a glass substrate and they are annealed at 450 °C for 1 h. Scanning electron microscopic (SEM) image of as‐deposited CdSe shows the spherical shaped grains distributed over entire glass substrate. When it is annealed at 450 °C, clusters of nano‐rods with star shaped grains are formed. The X‐ray diffraction (XRD) study of the as‐deposited films exhibits a polycrystalline nature and it undergoes a structural phase transition from the metastable cubic to the stable hexagonal phase when annealed at 450 °C. Optical band gap of as‐deposited films (2.0 eV) has a blue shift with respect to the bulk value (1.7 eV) due to quantum confinement. The band gap energies of the films are decreased from 2.0 eV to 1.9 eV due to annealing at the temperature of 450 °C. The electrical resistivity, Hall mobility and carrier concentration of as‐deposited and annealed films are determined.
Handedness in infants' tool use
Authors: Rat‐Fischer Lauriane , O'Regan J. Kevin , Fagard Jacqueline
Published: September 2012

In this study, we investigated whether hand preference influences infants' choice of what hand to use in grasping a new tool presented at the midline, and whether this will change in the course of learning the functionality of a tool. The tool was a rake within reach placed beside an out‐of‐reach toy presented either to its right or to its left. Forty‐eight infants from 16 to 22 months of age were tested. The results show that use of the right‐preferred hand to grasp the rake is strong as of 16 months of age and does not change significantly with age in the condition where using the right hand leads to a better outcome than using the left hand. In the condition where using the left‐non‐preferred hand makes toy retrieval easier, infants increasingly use the left hand with age. Thus, when grasping the tool, younger infants are more influenced by their hand preference than older infants, who are better at anticipating the most successful strategies. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 55: 860–868, 2013.
Mass spectrometric description of novel oxymetholone and desoxymethyltestosterone metabolites identified in human urine and their importance for doping control
Authors: Sobolevsky Tim , Rodchenkov Grigory
Published: September 2012

The metabolism of two anabolic steroids – oxymetholone and desoxymethyltestosterone – was reinvestigated to identify new targets potentially valuable for the antidoping analysis. Excretion urine samples from the laboratory reference collection were used in this study. Following fractionation of the urinary extract by means of high performance liquid chromatography (HPLC), each fraction was subjected to gas chromatography–mass spectrometry (GC‐MS) and gas chromatography‐tandem mass spectrometry (GC‐MS/MS) analysis after trimethylsilylation. About 20 metabolites were found for desoxymethyltestosterone and more than 40 for oxymetholone, with many of them being isomeric compounds. In addition to the well‐known reduced and hydroxylated metabolites, 18‐nor‐17,17‐dimethyl and 18‐nor‐17‐hydroxymethyl‐17‐methyl steroids were also identified. Having evaluated all the metabolites in terms of how long they could be detected, we suggest that 18‐nor‐2ξ,17β‐hydroxymethyl‐17α‐methyl‐5α‐androst‐13‐en‐3α‐ol is an important marker of oxymetholone abuse. In case of desoxymethyltestosterone, better detectability could be achieved if 18‐nor‐17,17‐dimethyl‐5α‐androst‐13‐en‐2ξ,3α‐diol is monitored. These novel metabolites could be detected using GC‐MS/MS at least for 14 days after administration of these anabolic steroids compared to 5–7 days for previously reported metabolites. Copyright © 2012 John Wiley & Sons, Ltd.
Transcriptional networks that mediate signals from reproductive tissues to influence lifespan
Authors: Ghazi Arjumand
Published: September 2012

Aging and reproduction are two defining features of our life. Historically, research has focused on the well‐documented decline in reproductive capacity that accompanies old age, especially with increasing maternal age in humans. However, recent experiments in model organisms such as worms, flies, and mice have shown that a dialogue in the opposite direction may be widely prevalent, and that signals from reproductive tissues have a significant effect on the rate of aging of organisms. This pathway has been described in considerable detail in the nematode Caenorhabditis elegans. Molecular genetic studies suggest that signals from the germline control a network of transcriptional regulators that function in the intestine to influence longevity. This network includes conserved, longevity‐promoting Forkhead Box (FOX) family transcription factors such as DAF‐16/FOXO and PHA‐4/FOXA, nuclear hormone receptors, as well as a transcription elongation factor, TCER‐1/TCERG1. Genomic and targeted molecular analyses have revealed that these transcription factors modulate autophagy, lipid metabolism, and possibly other cellular processes to increase the length of the animal's life. This review aims to provide an overview of the current knowledge on the genetic mechanism that underlies the reproductive control of aging with particular focus on the transcriptional regulators that constitute the main molecular players in this longevity pathway. genesis
51:1‐15, 2013. © 2012 Wiley Periodicals, Inc
B cells and CD22 are dispensable for the immediate antiinflammatory activity of intravenous immunoglobulins in vivo
Authors: Schwab Inessa , Seeling Michaela , Biburger Markus , Aschermann Susanne , Nitschke Lars , Nimmerjahn Falk
Published: September 2012

Intravenous immunoglobulins (IVIgs) efficiently suppress a variety of autoimmune diseases. Over the past few years several potential mechanisms underlying this antiinflammatory activity have become apparent. Among these, terminal sialic acid residues in the sugar moiety of the immunoglobulin G constant fragment have been shown to be critical for the antiinflammatory activity of IVIgs in models of rheumatoid arthritis and immunothrombocytopenia (ITP). More recently, B cells and the sialic acid‐binding protein CD22 were suggested to be involved in this IVIg‐dependent immunomodulatory pathway. To study whether B cells are directly involved in IVIg‐mediated suppression of acute autoimmune diseases, we tested the activity of IVIgs in mice deficient in B cells or CD22. We show that neither B cells nor CD22 are critical for the immediate antiinflammatory activity of IVIgs in mouse models of rheumatoid arthritis and ITP.
Urinary hydrophilic and hydrophobic metabolic profiling based on liquid chromatography‐mass spectrometry methods: Differential metabolite discovery specific to ovarian cancer
Authors: Chen Jing , Zhou Lina , Zhang Xiaoyan , Lu Xin , Cao Rui , Xu Congjian , Xu Guowang
Published: September 2012

Discovery of novel metabolite biomarker(s) for improved ovarian cancer diagnosis is of great importance. In this paper, the differences of urinary hydrophilic and hydrophobic metabolic profiling between healthy women, benign ovarian tumor, and ovarian cancer patients were studied by metabolomics strategy. Metabolites in urine were analyzed on hydrophilic interaction chromatography (HILIC) and reversed‐phase liquid chromatography (RPLC) coupled to MS. Data from HILIC or RPLC, positive or negative ion detection mode were found to be complementary. Data were filtered by orthogonal signal correction (OSC) method, and the three groups were discriminated by partial least squares discrimination analysis (PLS‐DA) models. By combining the four datasets, maximum information can be collected, and a PLS‐DA model was built after OSC filtering. The model based on combined dataset is superior to the ones based on the separate dataset, and important metabolites were screened based on the combined dataset model. Five metabolites were found to be specific to ovarian cancer and ten metabolites were considered commonly related to ovarian cancer and benign ovarian tumor. Combination of RPLC and HILIC separation, as well as positive and negative ion detection in metabolomic studies show advantages in collecting various metabolites information that helps us better understand the metabolic event.
Capillary electrophoretic separation‐based approach to determine the labeling kinetics of oligodeoxynucleotides
Authors: Kanavarioti Anastassia , Greenman Kevin L. , Hamalainen Mark , Jain Aakriti , Johns Adam M. , Melville Chris R. , Kemmish Kent , Andregg William
Published: September 2012

With the recent advances in electron microscopy (EM), computation, and nanofabrication, the original idea of reading DNA sequence directly from an image can now be tested. One approach is to develop heavy atom labels that can provide the contrast required for EM imaging. While evaluating tentative labels for the respective nucleobases in synthetic oligodeoxynucleotides (oligos), we developed a streamlined CE protocol to assess the label stability, reactivity, and selectivity. We report our protocol using osmium tetroxide 2,2′‐bipyridine (Osbipy) as a thymidine (T) specific label. The observed rates show that the labeling process is kinetically independent of both the oligo length, and the base composition. The conditions, i.e. temperature, optimal Osbipy concentration, and molar ratio of reagents, to promote 100% conversion of the starting oligo to labeled product were established. Hence, the optimized conditions developed with the oligos could be leveraged to allow osmylation of effectively all Ts in ssDNA, while achieving minimal mislabeling. In addition, the approach and methods employed here may be adapted to the evaluation of other prospective contrasting agents/labels to facilitate next‐generation DNA sequencing by EM.
DNA sequencing and bar‐coding using solid‐state nanopores
Authors: Atas Evrim , Singer Alon , Meller Amit
Published: September 2012

Nanopores have emerged as a prominent single‐molecule analytic tool with particular promise for genomic applications. In this review, we discuss two potential applications of the nanopore sensors: First, we present a nanopore‐based single‐molecule DNA sequencing method that utilizes optical detection for massively parallel throughput. Second, we describe a method by which nanopores can be used as single‐molecule genotyping tools. For DNA sequencing, the distinction among the four types of DNA nucleobases is achieved by employing a biochemical procedure for DNA expansion. In this approach, each nucleobase in each DNA strand is converted into one of four predefined unique 16‐mers in a process that preserves the nucleobase sequence. The resulting converted strands are then hybridized to a library of four molecular beacons, each carrying a unique fluorophore tag, that are perfect complements to the 16‐mers used for conversion. Solid‐state nanopores are then used to sequentially remove these beacons, one after the other, leading to a series of photon bursts in four colors that can be optically detected. Single‐molecule genotyping is achieved by tagging the DNA fragments with γ‐modified synthetic peptide nucleic acid probes coupled to an electronic characterization of the complexes using solid‐state nanopores. This method can be used to identify and differentiate genes with a high level of sequence similarity at the single‐molecule level, but different pathology or response to treatment. We will illustrate this method by differentiating the pol gene for two highly similar human immunodeficiency virus subtypes, paving the way for a novel diagnostics platform for viral classification.
Application of analytic hierarchy process and multicriteria decision analysis on waste management: A case study in iran
Authors: Madadian Edris , Amiri Leila , Abdoli Mohammad Ali
Published: September 2012

This research compares the various waste management strategies in Tabriz, Iran, and selects the best one by a decision‐making method. Selection the best strategy is conducted based on the Multi Criteria Analysis (MCA). In this regard, the Analytic Hierarchy Process (AHP), a mathematical technique for multicriteria decision making, and the Multi Criteria Analysis which is a developed decision‐making tool have been used. This research compares four waste management strategies including various practices such as Source Separation (SS), Biological and Mechanical Treatment (BMT), Refused Derived Fuel (RDF), Incineration and Landfilling. There are mainly eight criteria weighted based on the AHP method to select the best strategy. These criteria consist of required land for waste management, energy recovery, investment and operation costs, income to cost ratio (benefit), environmental impacts, and complexity of implementation and operation of process, public acceptance, and recycling materials. The results of this study demonstrate that the first strategy provides the best solution for waste management which includes SS, Compost production, BMT, RDF and Landfilling. Finally, study suggests various solutions that minimize environmental impacts and social cost and improve the public acceptance. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 810–817, 2013
The Mediating Role of Social Skills in the Relationship between Motor Ability and Internalizing Symptoms in Pre‐primary Children
Authors: Wilson Alicia , Piek Jan P. , Kane Robert
Published: September 2012

Impaired motor development can deprive a child of constructive engagement in early motor activities and thus diminish opportunities for the acquisition of key cognitive, social and emotional abilities. The aim of the current study was to test a model where social skills mediate the relationship between motor ability and internalizing symptoms in pre‐primary children. A cross‐sectional research design was employed to assess the mediation model using data from 234 boys and 241 girls aged 4 to 6 years. Structural equation modelling provided support for the mediating role of social skills as assessed by the child's teacher. Replication of these findings in longitudinal studies, elucidating how social skills relate to motor impairment, could have implications for the prevention of psychopathology in young children with motor impairment. Copyright © 2012 John Wiley & Sons, Ltd.