bluuebunny/crossref_metadata_2025 huggingface dataset:
Chiral Cp‐Rhodium(III)‐Catalyzed Asymmetric Hydroarylations of 1,1‐Disubstituted Alkenes
Authors: Ye Baihua , Donets Pavel A. , Cramer Nicolai
Published: December 2013

Metal‐catalyzed functionalizations at the ortho position of a directing group have become an efficient bond‐forming strategy. A wide range of transformations that employ Cp*RhIII catalysts have been described, but despite their synthetic potential, enantioselective variants that use chiral versions of the Cp* ligand remain scarce (Cp*=pentamethyl cyclopentadienyl). Cyclopentadienyl compounds with an atropchiral biaryl backbone are shown to be suitable ligands for the efficient intramolecular enantioselective hydroarylation of aryl hydroxamates. Dihydrofurans that bear methyl‐substituted quaternary stereocenters are thus obtained by CH functionalization under mild conditions.
Suzuki coupling reaction catalyzed heterogeneously by Pd(salen)/polyoxometalate compound: another example for synergistic effect of organic/inorganic hybrid
Authors: Tong Jinhui , Wang Haiyan , Cai Xiaodong , Zhang Qianping , Ma Hengchang , Lei Ziqiang
Published: December 2013

A hybrid compound consisting of palladium(salen) [salen = N,N′‐bis(salicylidene)ethylenediamine] complex covalently linked to a lacunary Keggin‐type polyoxometalate, K8[SiW11O39](POM), was synthesized and characterized by FT‐IR, elemental analysis, inductively coupled plasma and diffuse reflectance UV–visible spectroscopic methods. The hybrid, [Pd(salen)–POM], was investigated in the Suzuki cross‐coupling in EtOH/H2O under mild reaction conditions. In comparison to the corresponding organic and inorganic moiety, the hybrid has shown greatly improved catalytic activity, and much higher yields toward coupling products were obtained with a low catalyst loading for various aryl halides, including unreactive and sterically hindered ones. The catalyst also exhibited prominent recyclable performance and no obvious loss of activity was observed after six consecutive runs. Copyright © 2013 John Wiley & Sons, Ltd.
Synthesis of benzimidazoles by copper‐catalyzed aerobic oxidative domino reaction of 1,2‐diaminoarenes and arylmethyl halides
Authors: Qiu Dezhi , Wei Haidong , Zhou Lihong , Zeng Qingle
Published: December 2013

Arylmethyl halides are readily synthesized via halogenation from the basic raw materials, even in green processes. They are used to replace their downstream products to prepare medicinally important 2‐aryl benzimidazoles. CuBr‐catalyzed synthesis of 2‐aryl benzimidazoles from arylmethyl halides and 1,2‐diaminoarenes via a one‐pot domino reaction is developed. This new synthetic method is simple, practical and cost saving, and tolerates wide functional groups. A mechanism of CuBr‐catalyzed aerobic oxidative domino reaction via a one‐pot four‐step process is proposed. Copyright © 2013 John Wiley & Sons, Ltd.
Performance evaluation of CAESAR–QSAR output using PAHs as a case study
Authors: Vračko Marjan , Bobst Sol
Published: December 2013

The set of 16 polycyclic aromatic hydrocarbon compounds was examined with the Internet available quantitative structure–activity relationship (QSAR) CAESAR models. For mutagenicity, carcinogenicity, developmental toxicity, and skin sensitization, the report includes the predicted classifications, the analysis of applicability domains, and the similarity sets, which consist of the similar compounds from the training sets. These results were further analyzed with chemometrical methods, that is, hierarchical clustering, principal component analysis, and self‐organizing maps, which were used for clustering and to define the cluster indicators. Such analysis assists the users in planning the application of QSAR models for hazard communication in regulatory compliance and in research of new active compounds. Copyright © 2013 John Wiley & Sons, Ltd.
Chromo‐Fluorogenic Detection of Nitroaromatic Explosives by Using Silica Mesoporous Supports Gated with Tetrathiafulvalene Derivatives
Authors: Salinas Yolanda , Solano Marta V. , Sørensen Rebecca E. , Larsen Karina R. , Lycoops Jess , Jeppesen Jan O. , Martínez‐Máñez Ramón , Sancenón Félix , Marcos M. Dolores , Amorós Pedro , Guillem Carmen
Published: December 2013

Three new hybrid gated mesoporous materials (SN3‐1, SNH2‐2, and SN3‐3) loaded with the dye [Ru(bipy)3]2+ (bipy=bipyridine) and capped with different tetrathiafulvalene (TTF) derivatives (having different sizes and shapes and incorporating different numbers of sulfur atoms) have been prepared. The materials SN3‐1 and SN3‐3 are functionalized on their external surfaces with the TTF derivatives 1 and 3, respectively, which were attached by employing the “click” chemistry reaction, whereas SNH2‐2 incorporates the TTF derivative 2, which was anchored to the solid through an amidation reaction. The final gated materials have been characterized by standard techniques. Suspensions of these solids in acetonitrile showed “zero release”, most likely because of the formation of dense TTF networks around the pore outlets. The release of the entrapped [Ru(bipy)3]2+ dye from SN3‐1, SNH2‐2, and SN3‐3 was studied in the presence of selected explosives (Tetryl, TNT, TNB, DNT, RDX, PETN, PA, and TATP). SNH2‐2 showed a fairly selective response to Tetryl, whereas for SN3‐1 and SN3‐3 dye release was found to occur with Tetryl, TNT, and TNB. The uncapping process in the three materials can be ascribed to the formation of charge‐transfer complexes between the electron‐donating TTF units and the electron‐accepting nitroaromatic explosives. Finally, solids SNH2‐2 and SN3‐1 have been tested for Tetryl detection in soil with good results, pointing toward a possible use of these or similar hybrid capped materials as probes for the selective chromo‐fluorogenic detection of nitroaromatic explosives.
A Supramolecular Photosynthetic Model Made of a Multiporphyrinic Array Constructed around a C60 Core and a C60–Imidazole Derivative
Authors: Yoosaf K. , Iehl Julien , Nierengarten Iwona , Hmadeh Mohamed , Albrecht‐Gary Anne‐Marie , Nierengarten Jean‐François , Armaroli Nicola
Published: December 2013

The photophysical properties of a supramolecular fullerene–porphyrin ensemble resulting from the self‐assembly of a pyrrolidinofullerene–imidazole derivative (F1) with a multimetalloporphyrin array constructed around a hexasubstituted fullerene core (F(ZnP)12) have been investigated. The fullerene hexa‐adduct core of the host system does not play any active role in the cascade of photoinduced events of the supramolecular ensemble, indeed no intercomponent photoinduced processes could be observed in host F(ZnP)12. In contrast, upon axial coordination with the monosubstituted fullerene guest F1, a quantitative quenching of the fluorescence signal of the metalloporphyrins was observed for the supramolecular complex [F(ZnP)12(F1)n] both in polar and nonpolar solvents. In toluene, the supramolecular ensemble exhibits a charge transfer emission centered around 930 nm, suggesting the occurrence of intramolecular face‐to‐face interactions of F1 with neighboring metalloporphyrin moieties within the self‐assembled photoactive array. This mechanism is supported by the fact that a one order of magnitude increase in the binding constant was observed for the supramolecular complex [F(ZnP)12(F1)n] when compared with a reference system lacking the pyrrolidinofullerene unit. In benzonitrile, a long‐lived charge‐separated state (τ=0.3 μs) has been detected for the supramolecular adduct.
Chemische Sensoren in der Bioprozessanalytik
Authors: Demuth Caspar
Published: December 2013

Zu den wichtigsten chemischen Parametern, die in Bioprozessen überwacht werden, zählen der pH‐Wert und die Konzentration des gelösten Sauerstoffs. Für diese Messgrößen sind seit Jahren bewährte elektrochemische Sensoren im Einsatz. Erst seit kurzem beginnen sich in der Bioprozessanalytik neue Messprinzipien zu etablieren. Dazu zählen optische Sensoren, die sich insbesondere für den Einsatz in Einweg‐Bioreaktoren eignen. Entscheidende Faktoren für Prozess‐Sensoren sind heute nicht nur messtechnische Robustheit und Zuverlässigkeit, sondern auch eine einfache Bedienbarkeit und geringe Instandhaltungskosten.
Eine Boswelliasäure aus Weihrauch
Authors: Leutzsch Markus , Roth Alexander , Steinke Katrin , Sicker Dieter , Siehl Hans‐Ullrich , Schmid Maximilian , Zeller Klaus‐Peter , Berger Stefan
Published: December 2013

3‐O‐Acetyl‐11‐keto‐β‐boswelliasäure wurde aus pulverisiertem Weihrauchgranulat extrahiert und durch HPLC gereinigt. Alle analytischen Spektren sind vollständig entweder im Hauptteil oder in der supporting information wiedergegeben. Die NMR‐ sowie die Massenspektren werden eingehend interpretiert und mit theoretischen Berechnungen der 13C‐chemischen Verschiebungen verglichen. Das Projekt stellt eine Fortsetzung des Buches “Classics in Spectroscopy” von S. Berger und D. Sicker (Wiley‐VCH 2009) dar.
Chemie zum Heulen
Authors: Roth Klaus
Published: December 2013

Die Ig‐Nobelpreisträger in Chemie 2013 haben eindrucksvoll bewiesen, dass wissenschaftliche Forschung Menschen zunächst zum Lachen, aber dann zum Nachdenken bringen kann. Obwohl ein Studium der Zwiebelchemie komisch klingen mag, brachten uns die wissenschaftlichen Arbeiten der Preisträger der Lösung eines der dringlichsten Probleme der Kochkunst näher: die Tränenreizung beim Schneiden von frischen Zwiebeln. Die Anstrengungen der japanischen Arbeitsgruppe haben deswegen den IgNobelpreis und auch unsere Bewunderung verdient.
Vom “Weizenproblem” zur “Neuen Stickstofffrage”
Authors: Soentgen Jens
Published: December 2013

Das 20. Jahrhundert ist ein zentraler Wendepunkt in der Geschichte des Stickstoffs, weil es den bislang größten Eingriff des Menschen in einen natürlichen Stoffkreislauf mit sich gebracht hat. Ein Rätsel und ein Versprechen haben die Stickstoffgeschichte im 20. Jahrhundert maßgeblich bestimmt: Das “Wheat‐Problem”, die Weizenfrage, die der englische Chemiker Thomas Crookes 1896 mit ungeheurer Nachwirkung formulierte und das “Salpeterversprechen” der BASF im Jahre 1914 gegenüber der Heeresleitung des Reiches. Die Zukunft aber wird von der “Neuen Stickstofffrage” bestimmt werden. Doch der Reihe nach.
Forschung am Computer
Authors: Welter Kira
Published: December 2013

Rechner sind heute ein wichtiges Werkzeug in vielen Chemielabors. Mithilfe geeigneter Computerprogramme können Wissenschaftler hochkomplizierte molekulare Prozesse verstehen und sogar vorhersagen. Den Nobelpreis für Chemie 2013 teilen sich drei Forscher, die die Grundlage für solche Programme gelegt haben. Martin Karplus, Michael Levitt und Arieh Warshel werden für die Entwicklung von Computermodellen ausgezeichnet, die es ermöglichen, die Gesetze der klassischen Physik mit jenen der Quantenmechanik zu vereinigen, um komplexe Prozesse zu simulieren. Mit dem gewonnenen Verständnis können beispielsweise neue Medikamente und Materialien entwickelt, die Wirkung von Katalysatoren vorausberechnet oder die Funktion von Proteinen genauer untersucht werden.
Robust surface reconstruction of teeth from raw pointsets
Authors: Mao Zhihong , Park Kyusic , Lee Kunwoo , Li Xiongbing
Published: December 2013

This paper discusses a 3D robust dental surface reconstruction method. The surface reconstruction method usually consists of the following stages: mesh generation, surface registration, and surface merging. A large amount of noise will be accumulated after these three processes especially for the dental model with many sharp features of high curvature. To obtain an accurate dental surface, this paper first strengthens the mesh generation and the surface registration using optimal parameters. Then, a 3D robust dental surface reconstruction is performed by iteratively executing the smallest univalue segment assimilating nucleus filtering method and the surface attraction method. Finally, virtual scanning and real scanning models are introduced to validate the accuracy of the presented method. The experiments show that our method can robustly reconstruct the 3D dental model. Copyright © 2013 John Wiley & Sons, Ltd.
Characterization of Contact Structure for Woven Electronic Textile Using Conductive Polymer Micro‐Cantilever Array
Authors: Yamashita Takahiro , Khumpuang Sommawan , Miyake Koji , Itoh Toshihiro
Published: December 2013

A conductive polymer‐coated micro‐cantilever array made by the reel‐to‐reel continuous fiber process for use as an electrical contact component for woven electronic textile was investigated. We report a novel cantilever releasing method using air injection and the results of patternable CYTOP and organic conductive polymer using the nanoimprinting method. The conductive organic material used in this study was PEDOT:PSS [poly(3,4‐ethylenedioxythiophene) poly(4‐styrenesulfonate)]. A micro‐cantilever contact array was realized to compose the electrical circuit through the large area woven textile. A contact resistance of 480 Ω was maintained for over 500 times. Contact resistance measurements revealed that an electric current begins to flow with smaller contact force in PEDOT:PSS‐coated cantilever array structure than in PEDOT:PSS film structure. There is no appreciable wear on the cantilever surface due to its movability after 103 cycles of contact testing with 0.5 N contact force. Based on these results, PEDOT:PSS‐coated micro‐cantilever arrays have excellent potential as electrical contact components between weft and warp for woven electronic textiles. © 2013 Wiley Periodicals, Inc. Electron Comm Jpn, 97(1): 48–53, 2014; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11485
An Application of Fictitious Reference Iterative Tuning to State Feedback Control
Authors: Matsui Yoshihiro , Akamatsu Shunichi , Kimura Tomohiko , Nakano Kazushi , Sakurama Kazunori
Published: December 2013

This paper proposes the use of the fictitious reference iterative tuning (FRIT) method, which has been developed for controller gain tuning in single‐input single‐output systems, in state feedback gain tuning for a single‐input multivariable system. The transient response data for a single‐input multivariable plant obtained in closed‐loop operation is used for model matching by FRIT in the time domain. The data is also used in the frequency domain to estimate the stability and improve the control performance of the closed‐loop system with the state feedback gain tuned by the FRIT method. The FRIT method is applied to a state feedback control system for an inverted pendulum with an inertial rotor, and its usefulness is illustrated through experiments. © 2013 Wiley Periodicals, Inc. Electron Comm Jpn, 97(1): 1–11, 2014; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11506
Changes in evapotranspiration following wildfire in resprouting eucalypt forests
Authors: Nolan Rachael H. , Lane Patrick N. J. , Benyon Richard G. , Bradstock Ross A. , Mitchell Patrick J.
Published: December 2013

Forests that recover from disturbance predominately via vegetative resprouting may be expected to have different catchment water balance dynamics following wildfire than forests recovering from seed. However, the impacts of wildfire on forest water use are largely unknown in resprouting forest types. This is despite their dominance across the majority of southern Australia's forested catchments and the large areas burnt in recent years. We hypothesized that postfire changes in evapotranspiration (Et) would be a function of fire severity and topography and that partitioning of Et would change after fire because of altered stand structure. We tested these hypotheses by monitoring Et and component fluxes across different topographic positions and fire severities in a mixed eucalypt species forest located in water supply catchments for the city of Melbourne. For this forest type, wildfire triggers vegetative resprouting from lignotubers and epicormic shoots on the bole and branches of the overstorey trees, in addition to prolific seedling germination. Monitoring was undertaken over 1–3 years following the 2009 Black Saturday wildfires. We found that Et was on average 41% lower in forest burnt at high severity compared with unburnt forest, whereas Et from forest burnt at moderate severity was only 3% lower than unburnt forest over 1–2 years postfire but on average 9% higher over 2–3 years postfire. Et losses were driven by tree and shrub mortality in conjunction with lower transpiration in surviving trees. Lower Et was partially offset by regenerating seedlings that drove increases in forest floor Et and interception loss. Finally, we found that topography, through its effects on evaporative demand and forest structure, was a strong determinant of total Et but did not affect the nature of postfire recovery. Copyright © 2014 John Wiley & Sons, Ltd.
Iron‐Catalyzed π‐Activated C–O Ether Bond Cleavage with C–C and C–H Bond Formation
Authors: Fan Xiaohui , Cui Xiao‐Meng , Guan Yong‐Hong , Fu Lin‐An , Lv Hao , Guo Kun , Zhu Hong‐Bo
Published: December 2013

A novel and efficient allylic alkylation reaction between π‐activated ethers and allylsilane was realized under mild conditions through iron(III)‐catalyzed C–O ether bond cleavage. The present protocol provides an attractive approach for the construction of sp3–sp3 C–C bonds and can be potentially applied for the selective reduction of benzyl and allyl ethers to their corresponding hydrocarbon compounds by using triethylsilane as a hydride‐transfer reagent.
Regioselective Passerini and Passerini–Knoevenagel Reactions with vic‐Diketo Amides
Authors: Roßbach Jan , Harms Klaus , Koert Ulrich
Published: December 2013

The Passerini reaction of vic‐diketo amides with a variety of isocyanides and carboxylic acids has been examined. α‐Acyloxy β‐keto carboxamides were formed regioselectively as the major products. For the Passerini reactions with electron‐withdrawing‐group‐substituted acetic acids, a one‐pot Passerini–Knoevenagel reaction was accomplished by the addition of triethylamine.
Simultaneous Determination of Isoproterenol, Acetaminophen and Folic Acid Using a Novel Nanostructure‐Based Electrochemical Sensor
Authors: Mazloum‐Ardakani Mohammad , Hosseinzadeh Laleh , Khoshroo Alireza , Naeimi Hossein , Moradian Mohsen
Published: December 2013

In this study, a carbon paste electrode modified with (E)‐2‐((2‐chlorophenylimino)methyl)benzene‐1,4‐diol (CD) and titanium dioxide nanoparticles (TiO2) was used to prepare a novel electrochemical sensor. The objective of this novel electrode modification was to seek new electrochemical performances for the detection of isoproterenol (IP) in the presence of acetaminophen (AC) and folic acid (FA). Initially, cyclic voltammetry (CV) was used to investigate the redox properties of this modified electrode at various scan rates. In the following, the mediated oxidation of IP at the modified electrode was described. The results showed an efficient catalytic activity of the electrode for the electrooxidation of IP, which leads to a reduction in its overpotential by more than 235 mV. The value of the electron transfer coefficient (α), catalytic rate constant (kh) and diffusion coefficient (D) were calculated for IP, using electrochemical approaches. Based on differential pulse voltammetry (DPV), the oxidation of IP exhibited a dynamic range between 0.5 and 1000 µM and a detection limit (3σ) of 0.47 µM. DPV was used for simultaneous determination of IP, AC and FA at the modified electrode. Finally, this method was used for the determination of IP in real samples, using standard addition method.
Experimental validation of a simplified model for rolling isolation systems
Authors: Harvey P. Scott , Zéhil Gérard‐Philippe , Gavin Henri P.
Published: December 2013

Rolling isolation systems (RISs) protect mission‐critical equipment and valuable property from earthquake hazards by decoupling the dynamic responses of vibration‐sensitive objects from horizontal floor motions. These responses involve the constrained rolling of steel balls between bowl‐shaped surfaces. The light damping of steel balls rolling between steel plates can be augmented by adhering thin rubber sheets to the plates, thereby increasing the rolling resistance and decreasing the displacement demand on the RIS. An assessment of the ability of lightly‐ and heavily‐damped RISs to mitigate the hazard of seismically induced failures requires high‐fidelity models that can adequately capture the systems' intrinsic nonlinear behavior. The simplified model presented in this paper is applicable to RISs with any potential energy function, is amenable to both lightly‐ and heavily‐damped RISs, and is validated through the successful prediction of peak responses for a wide range of disturbance frequencies and intensities. The validated model can therefore be used to compute the spectra of peak floor motions for which displacement demands equal capacity. These spectra are compared with representative floor motion spectra provided by the American Society of Civil Engineers 7–10. The damping provided by rolling between thin viscoelastic sheets increases the allowable floor motion intensity by a factor of 2–3, depending on the period of motion. Acceleration responses of isolation systems with damping supplied in this fashion do not grow with increased damping, even for short‐period excitations. Copyright © 2013 John Wiley & Sons, Ltd.
Sensitivity Analysis for a Planar SOFC: Size Effects of the Porous Gas Diffusion Layer Underneath the Channel Rib
Authors: Zeng Y. K. , Fan P. , Zhang X. , Fu C. , Li J. , Li G.
Published: December 2013

This paper investigates the size effects of the gas diffusion layer underneath the channel rib on the performance of a planar solid oxide fuel cell (SOFC). Based on 3‐dimensional numerical simulations, the sensitivities of the electrical performance parameters (Nernst potential and current density) and the thermal performance parameters (heat generation and temperature) are examined as a function of variations in the channel rib width and anode thickness. The sensitivity values of the Nernst potential and current density are calculated to guide the design of a cell in a planar SOFC. In particular, the changes in ohmic losses for the interconnectors and anode are analyzed as a function of the variations of the channel rib width and anode thickness. The variations of the mole fractions of hydrogen, oxygen, and water in the active areas of the channel rib and the channel are presented, which provide sensitivity profiles for gas diffusion with respect to changes in the anode thickness.
Clustering of genomic breakpoints at the MLL locus in therapy‐related acute leukemia with t(4;11)(q21;q23)
Authors: Hasan Syed Khizer , Barba Gianluca , Metzler Markus , Divona Mariadomenica , Ottone Tiziana , Cicconi Laura , Falini Brunangelo , Mecucci Cristina , Lo‐Coco Francesco
Published: December 2013

Genomic characterization of translocation breakpoints is relevant to identify possible mechanisms underlying their origin. The consistent association of anthracylines (e.g., epirubicin and idarubicin) in inducing therapy‐related acute leukemias (t‐AL) with mixed lineage leukemia (MLL) gene rearrangement suggests that MLL translocations are causative events for t‐AL. Using asymmetric multiplex PCR strategy followed by direct DNA sequencing, we characterized the genomic breakpoints of the MLL and AFF1 genes in two patients who developed t‐AL with t(4;11)(q21;q23). Chemotherapeutic treatment of the primary disease in both patients included topoisomerase II (topo II) targeting agents. In one case, the MLL breakpoint was located in intron 9 at nucleotide position chr11:118354284 while the AFF1 breakpoint was in intron 3 at nucleotide position chr4:87992070. The breakpoint junction sequences revealed an insertion of two nucleotides at the MLL‐AFF1 junction. In the other patient, the MLL breakpoint was located in intron 11 at nucleotide position chr11:118359130‐32 and the AFF1 break was in intron 3 at nucleotide position chr4:87996215‐17. The MLL breakpoint found in the latter patient was identical to that of two previously reported cases, strongly suggesting the presence of a preferential site of DNA cleavage in the presence of topo II inhibitor. In addition, microhomologies at the breakpoint junctions were indicative of DNA repair by the non‐homologous end joining (NHEJ) pathway. This study further supports the evidence that MLL breakpoints in therapy‐related acute leukemia with MLL‐AFF1 are clustered in the telomeric half of the breakpoint cluster region that contains topo II recognition sites. © 2013 Wiley Periodicals, Inc.
Neue Untersuchungen zum Systemverhalten von Lockermassenfüllsäulen alter Tiefbauschächte
Authors: Scherbeck Rainer , Barciaga Thomas , König Diethard , Wollnik Frank , Schanz Tom
Published: December 2013

Der derzeitige Kenntnisstand zum Systemverhalten von mit Lockermassen versetzten Füllsäulen alter Tiefbauschächte ist durch die Untersuchungen der WBK aus den 1970er‐Jahren geprägt. Die damals erzielten Ergebnisse fanden Eingang in die fachspezifischen Richtlinien der Bergbehörde und manifestierten die mit Lockermassenfüllsäulen verbundene, besondere Gefahrensituation, z.B. über die Vorgabe eines Sogansatzes bei der Bemessung von Schachtabdeckungen.

Im Zuge der Aufstellung eines Risiko‐Managementsystems zum Umgang mit bergbaulichen Tagesöffnungen der RAG ergab sich die Notwendigkeit einer differenzierten Neubewertung der Lagestabilität von Lockermassenfüllsäulen. Hierzu wurde u.a. die Durchführung von Zentrifugen‐Modellversuchen mit Variation verschiedener Modellparameter konzipiert. In diesen Versuchen sollen insbesondere die Voraussetzungen bzw. die Auslöser für das plötzliche Auslaufen von Lockermassenfüllsäulen ermittelt werden. Im vorliegenden Beitrag werden die erzielten Ergebnisse und daraus getroffenen Ableitungen vorgestellt, aus denen eine differenzierte Sichtweise auf die Gefährlichkeit von Lockermassenfüllsäulen erkennbar ist.

Investigations on stability behaviour of non‐cohesive filled shafts. State‐of‐the‐art knowledge on stability of abandoned mining shafts filled with mostly granular, low cohesive materials is based on model testing by WBK in the 1970ies. Results from this research are incorporated in specific recommendations of the mining authorities, e.g. assuming suction load on shaft covering slabs. While introducing an active risk managing procedure on abandoned shafts, RAG decided to relaunch research activities on this topic. Using a geotechnical centrifuge facility, a comprehensive test series was performed with major results presented in this paper that lead to an updated view on fill stability in abandoned mining shafts.
Astrocyte‐specific activation of TNFR2 promotes oligodendrocyte maturation by secretion of leukemia inhibitory factor
Authors: Fischer Roman , Wajant Harald , Kontermann Roland , Pfizenmaier Klaus , Maier Olaf
Published: December 2013

Tumor necrosis factor (TNF) and its receptors TNFR1 and TNFR2 have pleiotropic effects in neurodegenerative disorders. For example, while TNFR1 mediates neurodegenerative effects in multiple sclerosis, TNFR2 is protective and contributes to remyelination. The exact mode of TNFR2 action, however, is poorly understood. Here, we show that TNFR2‐mediated activation of the PI3K‐PKB/Akt pathway in primary astrocytes increased the expression of neuroprotective genes, including that encoding the neurotrophic cytokine leukemia inhibitory factor (LIF). To investigate whether intercellular signaling between TNFR2‐stimulated astrocytes and oligodendrocytes plays a role in oligodendrocyte maturation, we established an astrocyte–oligodendrocyte coculture model, composed of primary astrocytes from huTNFR2‐transgenic (tgE1335) mice and oligodendrocyte progenitor cells (OPCs) from wild‐type mice, capable of differentiating into mature myelinating oligodendrocytes. In this model, selective stimulation of human TNFR2 on astrocytes, promoted differentiation of cocultured OPCs to myelin basic protein‐positive mature oligodendrocytes. Addition of LIF neutralizing antibodies inhibited oligodendrocyte differentiation, indicating a crucial role of TNFR2‐induced astrocyte derived LIF for oligodendrocyte maturation. GLIA 2014;62:272–283
Exploring resource use and associated costs in end‐of‐life care for older people with dementia in residential care homes
Authors: Amador Sarah , Goodman Claire , King Derek , Ng Yi Ting , Elmore Natasha , Mathie Elspeth , Machen Ina , Knapp Martin
Published: December 2013

Objective

The goals of this study are to describe end‐of‐life care costs of older people with dementia (OPWD) residents in care homes (CHs) with no on‐site nursing and evaluate the economic case for an intervention designed to improve end‐of‐life care for OPWD in CHs.

Methods

Phase 1 tracked for a year, from March 2009, health services received by 133 OPWD in six residential CHs in the East of England. CH and resident characteristics were obtained through standardised assessment tools, interviews with CH managers and publicly available information from the independent regulator of social care services in England. Phase 2 used a modified Appreciative Inquiry intervention that ran for 6 months from January 2011, in three of the six CHs. Wilcoxon matched‐pairs sign‐rank tests were conducted to compare total cost and cost components during Phases 1 and 2 for those residents who had participated in both.

Results

Costs for each resident in Phase 1 were about £2800 per month, including service, accommodation and medication. Resource use was associated with resident characteristics. The intervention was perceived as having a positive impact on working relationships between CHs and visiting health care practitioners. Following the intervention total service costs fell by 43%. Hospital care costs fell by 88%.

Conclusions

Results presented here represent early work in an under‐researched area of care. Appreciative Inquiry appears to improve and change working relationships with promising outcomes, but more research is needed to test these findings further with larger samples and more robust controls. Copyright © 2013 John Wiley & Sons, Ltd.
Activated Nrf2 impairs liver regeneration in mice by activation of genes involved in cell-cycle control and apoptosis
Authors: Köhler Ulrike A. , Kurinna Svitlana , Schwitter Dominik , Marti Andrea , Schäfer Matthias , Hellerbrand Claus , Speicher Tobias , Werner Sabine
Published: December 2013

The nuclear factor erythroid-derived 2, like 2 (Nrf2) transcription factor is a key regulator of the antioxidant defense system, and pharmacological activation of Nrf2 is a promising strategy for prevention of toxin-induced liver damage. However, the consequences of Nrf2 activation on liver regeneration (LR) have not been determined. To address this question, we generated mice expressing a constitutively active Nrf2 (caNrf2) mutant in hepatocytes. Expression of the transgene did not affect liver homeostasis. Surprisingly, however, there was no beneficial effect of Nrf2 activation on CCl4-induced liver injury and fibrosis. Most important, LR after partial hepatectomy was impaired in caNrf2-transgenic mice as a result of delayed hepatocyte proliferation and enhanced apoptosis of these cells after liver injury. Mechanistically, this involved up-regulation of the cyclin-dependent kinase inhibitor p15 and the proapoptotic protein Bcl2l11 (Bim). Using chromatin immunoprecipitation, we show that the p15 and Bcl2l11 genes are direct targets of Nrf2, which are activated under hyperproliferative conditions in the liver. Conclusion: Activated Nrf2 delays proliferation and induces apoptosis of hepatocytes in the regenerating liver. These negative effects of Nrf2 activation on LR should be considered when Nrf2-activating compounds are used for prevention of liver damage. (Hepatology 2014;60:670–678)
Inhibition of ATP citrate lyase induces triglyceride accumulation with altered fatty acid composition in cancer cells
Authors: Migita Toshiro , Okabe Sachiko , Ikeda Kazutaka , Igarashi Saori , Sugawara Shoko , Tomida Akihiro , Soga Tomoyoshi , Taguchi Ryo , Seimiya Hiroyuki
Published: December 2013

De novolipogenesis is activated in most cancers and several lipogenic enzymes have been implicated as therapeutic targets. Here, we demonstrate a novel function of the lipogenic enzyme, ATP citrate lyase (ACLY), in lipid metabolism in cancer cells. ACLY depletion by small interfering RNAs caused growth suppression and/or apoptosis in a subset of cancer cell lines. To investigate the effect of ACLY inhibition on lipid metabolism, metabolome and transcriptome analysis was performed. ACLY depletion blocks the fatty acid chain elongation from C16 to C18 in triglyceride (TG), but not in other lipid classes. Meanwhile, wild‐type ACLY overexpression enhanced fatty acid elongation of TG, whereas an inactive mutant ACLY did not change it. ACLY depletion‐mediated blockade of fatty acid elongation was coincident with downregulation of long‐chain fatty acid elongase ELOVL6, which resides in endoplasmic reticulum (ER). Paradoxically, ACLY depletion‐mediated growth suppression was associated with TG accumulation. ACLY depletion downregulated the expression of carnitine palmitoyltransferase 1A, which is a mitochondrial fatty acid transporter. Consistent with this finding, metabolome analysis revealed that ACLY positively regulates the carnitine system, which plays as an essential cofactor for fatty acid transport across mitochondrial membrane. AICAR, an activator of mitochondrial fatty acid oxidation (FAO), significantly reduced ACLY depletion‐mediated TG accumulation. These data indicate that inhibition of ACLY might affect both fatty acid elongation in ER and FAO in mitochondria, thereby explaining the TG accumulation with altered fatty acid composition. This phenotype may be a hallmark of growth suppression mediated by ACLY inhibition.
Multilayered molecular profiling supported the monoclonal origin of metastatic renal cell carcinoma
Authors: Huang Yi , Gao Shengjie , Wu Song , Song Pengfei , Sun Xiaojuan , Hu Xueda , Zhang Shiqiang , Yu Yuan , Zhu Jialou , Li Cailing , Qin Zike , Xie Liangfu , Yao Qiong , Tang Aifa , Li Zesong , Guo Guangwu , Wan Shengqing , Dong Pei , Sun Liang , Li Weiping , Wang Daping , Gui Yaoting , Yang Huanming , Zhou Fangjian , Zhang Xiuqing , Cai Zhiming
Published: December 2013

Primary renal cell carcinomas (pRCCs) have a high degree of intratumoral heterogeneity and are composed of multiple distinct subclones. However, it remains largely unknown that whether metastatic renal cell carcinomas (mRCCs) also have startling intratumoral heterogeneity or whether development of mRCCs is due to early dissemination or late diagnosis. To decipher the evolution of mRCC, we analyzed the multilayered molecular profiles of pRCC, local invasion of the vena cava (IVC), and distant metastasis to the brain (MB) from the same patient using whole‐genome sequencing, whole‐exome sequencing, DNA methylome profiling, and transcriptome sequencing. We found that mRCC had a lower degree of heterogeneity than pRCC and was likely to result from recent clonal expansion of a rare, advantageous subclone. Consequently, some key pathways that are targeted by clinically available drugs showed distinct expression patterns between pRCC and mRCC. From the genetic distances between different tumor subclones, we estimated that the progeny subclone giving rise to distant metastasis took over half a decade to acquire the full potential of metastasis since the birth of the subclone that evolved into IVC. Our evidence supported that mRCC was monoclonal and distant metastasis occurred late during renal cancer progression. Thus, there was a broad window for early detection of circulating tumor cells and future targeted treatments for patients with mRCCs should rely on the molecular profiles of metastases.
ChemNetworks: A complex network analysis tool for chemical systems
Authors: Ozkanlar Abdullah , Clark Aurora E.
Published: December 2013

Many intermolecular chemical interactions persist across length and timescales and can be considered to form a “network” or “graph.” Obvious examples include the hydrogen bond networks formed by polar solvents such as water or alcohols. In fact, there are many similarities between intermolecular chemical networks like those formed by hydrogen bonding and the complex and distributed networks found in computer science. Contemporary network analyses are able to dissect the complex local and global changes that occur within the network over multiple time and length scales. This work discusses the ChemNetworks software, whose purpose is to process Cartesian coordinates of chemical systems into a network/graph formalism and apply topological network analyses that include network neighborhood, the determination of geodesic paths, the degree census, direct structural searches, and the distribution of defect states of network. These properties can help to understand the network patterns and organization that may influence physical properties and chemical reactivity. The focus of ChemNetworks is to quantitatively describe intermolecular chemical networks of entire systems at both the local and global levels and as a function of time. The code is highly general, capable of converting a wide variety of systems into a chemical network formalism, including complex solutions, liquid interfaces, or even self‐assemblies. © 2013 Wiley Periodicals, Inc.
Synthesis and In Vitro Antimicrobial Screening of New Azetidin‐2‐ones of 5‐Ethyl Pyridine‐2‐ethanol
Authors: Patel Navin B. , Patel Hemant R. , Shaikh Faiyazalam M. , Rajani Dhanji
Published: December 2013

A new series of azetidinones is described in this paper; Schiff base (4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n, 4o) were synthesized from 4‐[2‐(5‐ethylpyridin‐2‐yl)ethoxy]benzaldehyde, which was used to synthesize azetidinones (5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n, 5o), (6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n, 6o), and (7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k, 7l, 7m, 7n, 7o). The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, 1H NMR, and 13C NMR spectral data. All the products were screened against different strains of bacteria and fungi. Most of the monosubstituted and disubstituted chloro groups are more effective to both bacterial and fungal species in comparison with the standard drugs.
A Convenient Protocol for the Synthesis of 2‐(2′‐Hydroxy‐5′‐carboxyphenyl)‐2H‐benzotriazole to Avoid Decarboxylation When Using p‐Hydroxybenzoic Acid as Coupling Component
Authors: Ma Wei , Tuo Tingting , Hu Jingqiang , Liu Yong , Zhang Shufen
Published: December 2013

In the study of the synthesis of 2‐(2′‐hydroxy‐5′‐carboxyphenyl)‐2H‐benzotriazole, we found that decarboxy intermediate‐4‐((2‐nitrophenyl)diazenyl)phenol was obtained when using p‐hydroxybenzoic acid as coupling component. A convenient protocol for the synthesis of 2‐(2′‐hydroxy‐5′‐carboxyphenyl)‐2H‐benzotriazole is reported with methyl‐p‐hydroxybenzoate as coupling component. Different dizao components and different coupling components were also used for further investigation of decarboxylation.
In‐chain neutral hydrocarbon loss from crocin apocarotenoid ester glycosides and the crocetin aglycon (Crocus sativus L.) by ESI‐MSn (n = 2, 3)
Authors: Pittenauer Ernst , Koulakiotis Nikolaos Stavros , Tsarbopoulos Anthony , Allmaier Guenter
Published: December 2013

The stigmas of Crocus sativus L. have been used as spice and colorant agent (i.e. saffron) for more than 4000 years. For an updated structural investigation of the aglycon present in the glycosylated crocetin apocarotenoids (i.e. crocins), seven representative derivatives ranging from one up to five glucosyl‐residues with a maximum number of three monosaccharides per glycosylation site (glucose, gentiobiose, gentiotriose and neapolitanose) were isolated and purified by high‐performance liquid chromatography. The compounds selected for further mass spectrometric investigation include glucosyl‐, bis‐glucosyl‐, gentiobiosyl‐, gentiobiosyl‐glucosyl‐, bis‐gentiobiosyl‐, gentiobiosyl‐gentiotriosyl‐ and gentiobiosyl‐neapolitanosyl‐crocetin. Electrospray ionization in combination with low‐energy collision‐induced dissociation/tandem mass spectrometry of sodiated crocin precursor ions utilizing either a 3D‐ion trap (MSn, n = 2, 3) or a QqTOF instrument, with the latter providing accurate mass determination with an accuracy of ±1–3 ppm or better at a resolution of 10 000 (full width at half maximum), was used. Major fragmentation pathways included loss of either one or two carbohydrate substituents leading to the sodiated aglycon without interglycosidic bond cleavage during in MS2‐experiments. All sodiated precursor ions and major product ions were accompanied by a loss of 92 Da, which was elucidated as C7H8‐loss from the aglycon by skeletal rearrangement via an eight‐membered transition state as previously described for intact C40‐carotenoids. Copyright © 2013 John Wiley & Sons, Ltd.
Application of 13C isotope labeling using liquid chromatography mass spectrometry (LC‐MS) to determining phosphate‐containing metabolic incorporation
Authors: Bhowmik Salil Kumar , Putluri Vasanta , Kommagani Ramakrishna , Konde Sai Aparna , Lydon John P. , Sreekumar Arun , Putluri Nagireddy
Published: December 2013

Here, we describe an approach wherein negative electrospray ionization mass spectrometry has used to understand the relative flux through phosphate containing metabolic intermediates associated with central carbon metabolism after administering cells with 13C‐labeled substrates. The method was applied to examine the 13C incorporation through glycolysis in T47D breast cancer cells and showed reduction of glycolytic relative flux upon treatment with 2‐Deoxyglucose. Copyright © 2013 John Wiley & Sons, Ltd.
Quadrupole mass filter operation under the influence of magnetic field
Authors: Syed S. U. A. H. , Maher S. , Taylor S.
Published: December 2013

This work demonstrates resolution enhancement of a quadrupole mass filter (QMF) under the influence of a static magnetic field. Generally, QMF resolution can be improved by increasing the number of rf cycles an ion experiences when passing through the mass filter. In order to improve the resolution, the dimensions of the QMF or the operating parameters need to be changed. However, geometric modifications to improve performance increase the manufacturing cost and usually the size of the instrument. By applying a magnetic field, a low‐cost, small footprint instrument with reduced power requirements can be realized.

Significant improvement in QMF resolution was observed experimentally for certain magnetic field conditions, and these have been explained in terms of our theoretical model developed at the University of Liverpool. This model is capable of accurate simulation of spectra allowing the user to specify different values of mass spectrometer dimensions and applied input signals. The model predicts enhanced instrument resolution R>26 000 for a CO2 and N2 mixture with a 200‐mm long mass filter operating in stability zone 3 via application of an axial magnetic field. Copyright © 2013 John Wiley & Sons, Ltd.
The mystery of the occluded port that allowed blood withdrawal: Is it safe to use standard needles to access ports? A case report and literature review
Authors: Cataldo Rita , Costa Fabio , Vitiello Michelangelo , Brescia Fabrizio , Proscia Paola , Falco Clementina , Carassiti Massimiliano
Published: December 2013

A frequent complication of totally implantable central venous access devices (TIVADs) is withdrawal occlusion. We describe a case of rare dysfunction of TIVADs: blood withdrawal was possible, whereas infusion was not. A further investigation demonstrated that during infusion, a silicone core, probably produced by hypodermic needle puncture, occluded the reservoir outlet hole. The silicone septum puncture by standard needles instead of non‐coring ones may reduce the device effectiveness and expose patients to serious complications. J. Surg. Oncol. 2014 109:500–503. © 2013 Wiley Periodicals, Inc.
Identification of prognostic factors and the impact of palliative resection on survival of patients with stage IV hepatolithiasis‐associated intrahepatic cholangiocarcinoma
Authors: Zhang Guo‐wei , Lin Jian‐hua , Qian Jian‐ping , Zhou Jie
Published: December 2013

Background

Hepatolithiasis‐associated intrahepatic cholangiocarcinoma (IHHCC) has a poor prognosis, because of lower curative resection rate when diagnosed in the advanced stage. There has been insufficient data regarding prognostic factors and the impact of palliative resection on its outcome.

Methods

A retrospective analysis of 78 eligible patients with stage IV IHHCC was performed. The potential prognostic factors were assessed by univariate and multivariate analyses. Patients were divided into groups A (margin positive) and B (nonresection) based on surgical methods. Demographic and operative data were compared.

Results

Of 78 surgeries, R1 was achieved in 11, R2 in 21 and nonresection in 46 patients. Median overall survival (OS) of the entire cohort was 10.5 months. Surgery (P < 0.01), tumor differentiation (P = 0.03), AJCC stage (P < 0.01), and serum CEA levels (P < 0.01) were independent prognostic factors. Significant differences were achieved in OS (P < 0.01), operation time (P < 0.01), estimated blood loss (P < 0.01), and postoperative complications (P = 0.02) between groups A and B.

Conclusions

For patients with stage IV IHHCC, palliative resection is a rational and effective treatment. Normal serum CEA levels, higher tumor differentiation, and stage IVa predict good prognosis in stage IV IHHCC. J. Surg. Oncol. 2014 109:494–499. © 2013 Wiley Periodicals, Inc.
Differential pharmacokinetics and the brain distribution of morphine and ephedrine constitutional isomers in rats after oral administration with Keke capsule using rapid‐resolution LC–MS/MS
Authors: Song Yonggui , Su Dan , Lu Tulin , Mao Chunqin , Ji De , Liu Yali , Wei Binbin , Fan Ronghua
Published: December 2013

Opioid and ephedra alkaloids known as the active ingredients for Keke capsule, which is used to treat coughs and bronchial asthma, could have potential adverse effects on the central nervous system. Therefore, an efficient, sensitive rapid‐resolution LC–MS/MS method for the simultaneous determination of morphine, ephedrine, and pseudoephedrine in rat plasma and brain tissue homogenate has been developed. The method was validated in the plasma and brain tissue samples, showed good linearity over a wide concentration range (r2 > 0.99). The intra‐ and interday assay variability was less than 15% for all analytes, and the accuracy was between −8.8 and 5.7%. The study provided the pharmacokinetics profiles and the brain regional distribution of the three active alkaloids after oral administration of Keke capsule. The results also indicated that significant difference in pharmacokinetics parameters of the epimers was observed between ephedrine and pseudoephedrine.
Evaluation of a PEG/hydroxypropyl starch aqueous two‐phase system for the separation of monoclonal antibodies from cell culture supernatant
Authors: Wu Qiang , Lin Dong‐Qiang , Zhang Qi‐Lei , Gao Dong , Yao Shan‐Jing
Published: December 2013

In this study, an aqueous two‐phase system (ATPS) with PEG and hydroxypropyl starch (HPS) was used to separate monoclonal antibody (mAb) from Chinese hamster ovary cell culture supernatant. The phase diagram of the PEG/HPS ATPS was determined, and the effects of NaCl addition were investigated. The results showed that NaCl addition could lead to a shift of the binodal curve and that phase separation would occur at higher PEG and HPS concentrations. The effects of NaCl addition, pH, and the load of cell supernatant on the partitioning of mAb in a PEG/HPS ATPS were investigated. It was found that with 6% cell supernatant and 15% NaCl addition at pH 6.0, the yield of mAb in the upper phase was 96.7% with a purity of 96.0%. The back‐extraction of mAb with a PEG/phosphate ATPS were also studied, and the results showed that after the two‐step extraction with ATPSs the purity of mAb could reach 97.6 ± 0.5% with a yield of 86.8 ± 1.0%, which was comparable to the purification with Protein A chromatography. These results indicate that the two‐step extraction with PEG/HPS and PEG/phosphate ATPSs might be a promising alternative for the separation of mAb from cell culture supernatant.