bluuebunny/crossref_metadata_2025 huggingface dataset:
Durchstanzbewehrung für Elementdecken nach Eurocode 2
Authors: Siburg Carsten , Hegger Josef , Furche Johannes , Bauermeister Ulrich
Published: March 2014

Das Tragverhalten von speziellen Gitterträgern als Durchstanzbewehrung wurde in Bauteilversuchen an 18 cm bis 36 cm dicken teilvorgefertigten Stahlbetonplatten mit horizontaler Verbundfuge untersucht. Variiert wurde unter anderem auch die Anordnung der vorgefertigten Platten. Die ermittelten Durchstanzwiderstände und das beobachtete Tragverhalten bestätigen die Effektivität dieser Bewehrungselemente. Die Versuche führten zur Erteilung einer europäischen technischen Zulassung (ETA) auf der Bemessungsgrundlage von Eurocode 2.

Punching shear reinforcement for semi precast slabs according to Eurocode 2

The load bearing behaviour of special lattice girders functioning as punching shear reinforcement has been tested in full scale tests with 18 cm up to 36 cm thick semi precast slabs with horizontal composite joints. Varied was among other parameter also the arrangement of the precast plates. The determined punching shear resistance and the load bearing behaviour confirmed the effectiveness of this reinforcement. These tests had led to an European Technical Approval (ETA) based on Eurocode 2.
Textilbetonherstellung im Gießverfahren mit Hilfe von Abstandhaltern
Authors: Walther Tobias , Schladitz Frank , Curbach Manfred
Published: March 2014

Zur effizienten und seriellen Herstellung von Textilbetonplatten im Gießverfahren fehlten bis zum jetzigen Zeitpunkt geeignete Abstandhalter, mit denen eine sichere Fixierung der textilen Bewehrung in einer Schalung möglich ist. Das Abstandhaltersystem DistTEX eröffnet jedoch diese Möglichkeiten. Die Lage der textilen Bewehrung bleibt während des Gießprozesses erhalten. Die Handhabung und die Einflüsse auf die Eigenschaften von Textilbetonbauteilen mit diesem neuen Abstandhaltersystem wurden an der TU Dresden untersucht und ausgewertet. Die Abstandhalter überzeugten in ihrer Anwendung und ihren Eigenschaften. Es konnte keine Minderung der Tragfähigkeit festgestellt werden. Die visuellen Untersuchungen der Betonoberflächen ergaben, dass die verwendeten Abstandhalter weder unter Normbedingungen noch unter Temperaturschwankungen von bis zu 60 K negativen Einfluss haben. Bei der Überprüfung der Lage der textilen Bewehrung konnten nur leichte Abweichungen von der Solllage festgestellt werden.

Textile Reinforced Concrete produced in casting process with Spacer

Up to now, an efficient or serial fabrication of textile reinforced concrete slabs through casting was impossible due to the lack of spacers for fixing the textile reinforcement in a formwork. However, the spacer‐system DistTEX makes this possible now. The position of the textile reinforcement remains the same during the casting process. The handling of textile reinforced parts with this new spacer‐system and its influence on the properties were researched and analysed at TU Dresden. The spacer‐system was convincing with regard to its application and properties. Apparently, the load‐bearing capacity was not reduced. A visual analysis of the concrete surface did not reveal any negative influences of the applied spacer‐system either under normal conditions or under temperature variation of up to 60 K. The position of the textile reinforcement proved to have drifted only slightly from the reference position.
Self‐Immolative Bioluminogenic Quinone Luciferins for NAD(P)H Assays and Reducing Capacity‐Based Cell Viability Assays
Authors: Zhou Wenhui , Leippe Donna , Duellman Sarah , Sobol Mary , Vidugiriene Jolanta , O'Brien Martha , Shultz John W. , Kimball Joshua J. , DiBernardo Céline , Moothart Leonard , Bernad Laurent , Cali James , Klaubert Dieter H. , Meisenheimer Poncho
Published: March 2014

Highly sensitive self‐cleavable trimethyl lock quinone‐luciferin substrates for diaphorase were designed and synthesized to measure NAD(P)H in biological samples and monitor viable cells via NAD(P)H‐dependent cellular oxidoreductase enzymes and their NAD(P)H cofactors.
RNA‐Directed Amino Acid Coupling as a Model Reaction for Primitive Coded Translation
Authors: Harada Kazuo , Aoyama Shoko , Matsugami Akimasa , Kumar Penmetcha K. R. , Katahira Masato , Kato Nobuo , Ohkanda Junko
Published: March 2014

The stereochemical theory claims that primitive coded translation initially occurred in the RNA world by RNA‐directed amino acid coupling. In this study, we show that the HIV Tat aptamer RNA is capable of recognizing two consecutive arginine residues within the Tat peptide, thus demonstrating how RNA might be able to position two amino acids for sequence‐specific coupling. We also show that this RNA can act as a template to accelerate the coupling of a single arginine residue to the N‐terminal arginine residue of a peptide primer. The results might have implications for our understanding of the origin of translation.
A case of self‐harm by alcohol intoxication resulted in unintended in‐hospital death
Authors: Nagashima Goro , Kamimura Miho , Kato Akihito , Fukuda Yasunobu , Noda Masayuki , Morishima Hiroyuki , Tanaka Taku , Umano Yuki
Published: March 2014

Key Clinical Message

In‐hospital hanging during a confusional state from alcohol intoxication is rare. To treat cases of acute alcohol intoxication, careful observation will be needed to avoid accidental psychological reactions.
Renal failure with a large bladder calculus related to a foreign body: a case report
Authors: Minter Janelle , Chiovaro Joseph
Published: March 2014

Key Clinical Message

We encountered a patient with renal failure in the setting of long‐standing difficulty urinating, which he previously treated with intermittent self‐catheterizations. Imaging showed a large urinary calculus in the bladder. This case illustrates the importance of taking a detailed history and the dramatic long‐term effects of bladder calculi.
Whole‐Cell Teabag Catalysis for the Modularisation of Synthetic Enzyme Cascades in Micro‐Aqueous Systems
Authors: Wachtmeister Jochen , Jakoblinnert Andre , Kulig Justyna , Offermann Heike , Rother Dörte
Published: March 2014

Combining enzymes to form multi‐step enzyme cascades has great potential to replace existing chemical routes with high atom‐efficient and eco‐efficient synthesis strategies as well as to grant access to new products, especially those with multi‐stereogenic centres. However, easy solutions and tools for setting up appropriate reaction conditions and process modes are hardly available. The utilisation of teabags filled with whole cells has several advantages, such as 1) simplified handling and recovery of catalyst, 2) easy combination of various catalysts from catalyst toolboxes, 3) fast testing of different operating modes during cascadation and 4) simplified downstream processing. One of the main advantages is that lyophilised whole‐cell catalysts can be applied in micro‐aqueous media, allowing high substrate loads (also of poorly water‐soluble substrates) and concomitantly enabling high catalyst stability. This was demonstrated herein for a synthetic two‐step cascade towards chiral 1,2‐diols starting from cheap aldehydes. The carboligation of two aldehydes using Pseudomonas fluorescens benzaldehyde lyase and subsequent oxidoreduction with Ralstonia sp. alcohol dehydrogenase yielded 1‐phenylpropane‐1,2‐diol [(1R,2R)‐PPD] in concentrations of up to 339 mM and excellent enantiomeric and diastereomeric excesses >99 %. Therefore, the combination of whole‐cell catalysis and teabag modularisation allows cheap, easy‐to‐apply and efficient catalyst preparation to test enzyme combinations and optimal reaction conditions up to the preparative scale. By circumventing catalyst purification and immobilisation, and enabling high substrate loadings compared to those in aqueous systems, efficient production of a chiral diol with extraordinarily high product concentrations can be achieved.
One‐Step Production of Sulfur and Nitrogen Co‐doped Graphitic Carbon for Oxygen Reduction: Activation Effect of Oxidized Sulfur and Nitrogen
Authors: Wang Jing , Xu Zheng , Gong Yutong , Han Chuanlong , Li Haoran , Wang Yong
Published: March 2014

Oxidized sulfur and nitrogen co‐doped graphitic carbon (SN‐G) was one‐step synthesized simply by annealing a solid mixture of D‐glucosamine hydrochloride, melamine, and trithiocyanuric acid. By tailoring the additive dosage and the pyrolysis temperature, correlations between the structure, composition, and electrochemical performance of SN‐G were systematically elucidated. To our excitement, the SN3‐G sample pyrolyzed at 900 °C with a dominant oxidized sulfur content exhibited striking electrocatalytic activity in alkaline medium, which was free from the crossover effect, and its long‐term durability was superior to that of commercial Pt/C (20 wt %). Furthermore, oxidized sulfur that was reported to be chemically inactive for the ORR was proven to be active, which was supported by both experimental results and density functional theory calculations.
A Simple Non‐Gassing, Direct Current, Electro‐Osmotic Pump: Carbon Paper/Ceramic Frit/Carbon Paper
Authors: Nagarale Rajaram K. , Heller Adam
Published: March 2014

We report the simplest of the small, non‐gassing, low‐voltage, direct‐current, electro‐osmotic pumps, providing enough flow for the delivery of drugs. It consists merely of a ceramic frit sandwiched between two plasma‐treated carbon paper electrodes; the plasma treatment adds electro‐oxidizable hydroquinone and electro‐reducible quinone surface functions. Protons released upon the electro‐oxidation of the hydroquinone surface functions move concertedly in the applied electric field at the ceramic membrane water interface and by dragging bulk water, causing water to flow at a rate of 10 μL cm−2 min−1 at an applied potential of 1 V across a 2 mm‐thick membrane. Following plasma treatment of the carbon paper for 45 min, the flow persists for 18 h, in which 10 mL cm−2 of water is pumped.
Flexible and Rigid Amine‐Functionalized Microporous Frameworks Based on Different Secondary Building Units: Supramolecular Isomerism, Selective CO2 Capture, and Catalysis
Authors: Haldar Ritesh , Reddy Sandeep K. , Suresh Venkata M. , Mohapatra Sudip , Balasubramanian Sundaram , Maji Tapas Kumar
Published: March 2014

We report the synthesis, structural characterization, and porous properties of two isomeric supramolecular complexes of ([Cd(NH2bdc)(bphz)0.5]⋅DMF⋅H2O}n (NH2bdc=2‐aminobenzenedicarboxylic acid, bphz=1,2‐bis(4‐pyridylmethylene)hydrazine) composed of a mixed‐ligand system. The first isomer, with a paddle‐wheel‐type Cd2(COO)4 secondary building unit (SBU), is flexible in nature, whereas the other isomer has a rigid framework based on a μ‐oxo‐bridged Cd2(μ‐OCO)2 SBU. Both frameworks are two‐fold interpenetrated and the pore surface is decorated with pendant −NH2 and NN functional groups. Both the frameworks are nonporous to N2, revealed by the type II adsorption profiles. However, at 195 K, the first isomer shows an unusual double‐step hysteretic CO2 adsorption profile, whereas the second isomer shows a typical type I CO2 profile. Moreover, at 195 K, both frameworks show excellent selectivity for CO2 among other gases (N2, O2, H2, and Ar), which has been correlated to the specific interaction of CO2 with the −NH2 and NN functionalized pore surface. DFT calculations for the oxo‐bridged isomer unveiled that the −NH2 group is the primary binding site for CO2. The high heat of CO2 adsorption (ΔHads=37.7 kJ mol−1) in the oxo‐bridged isomer is realized by NH2⋅⋅⋅CO2/aromatic π⋅⋅⋅CO2 and cooperative CO2⋅⋅⋅CO2 interactions. Further, postsynthetic modification of the −NH2 group into −NHCOCH3 in the second isomer leads to a reduced CO2 uptake with lower binding energy, which establishes the critical role of the −NH2 group for CO2 capture. The presence of basic −NH2 sites in the oxo‐bridged isomer was further exploited for efficient catalytic activity in a Knoevenagel condensation reaction.
Absolute Stereochemistry of a 4 a‐Hydroxyriboflavin Analogue of the Key Intermediate of the FAD‐Monooxygenase Cycle
Authors: Iwahana Soichiro , Iida Hiroki , Yashima Eiji , Pescitelli Gennaro , Di Bari Lorenzo , Petrovic Ana G. , Berova Nina
Published: March 2014

The biological action of flavoenzymes, such as flavin adenine dinucleotide (FAD)‐containing monooxygenase, involves the formation of oxygenated flavin derivatives, such as 4 a‐hydroperoxyflavin and 4 a‐hydroxyflavin, in which a new center of chirality is created at the 4 a position during the enzymatic reactions. So far, the absolute configuration of this center of chirality in natural 4 a‐oxygenated flavins has remained unknown in spite of its key importance for the diverse functions of flavoenzymes. Herein, we report the 4 a‐hydroxy adduct 3 of 3‐benzyl‐5‐ethyl‐10‐(tetraacetyl‐D‐ribityl)flavinium (1), one of the key intermediates involved in the enantioselective organocatalytic oxidation of sulfides to sulfoxides. The 4 a‐hydroxyflavin diastereomers (+)‐3 and (−)‐3, separated by HPLC, were characterized by electronic circular dichroism (CD) spectroscopy. Their absolute configurations at the 4 a position were, for the first time, determined by comparing experimental CD spectra with those calculated by means of time‐dependent density functional theory (TDDFT) on DFT‐optimized structures obtained after an extensive conformation analysis.
Comparative Studies of Thermally Induced Homolytic CarbonCarbon Bond Cleavage Reactions of Strained Dicarba[2]ferrocenophanes and Their Ring‐Opened Oligomers and Polymers
Authors: Russell Andrew D. , Gilroy Joe B. , Manners Ian
Published: March 2014

Reactivity studies of dicarba[2]ferrocenophanes and also their corresponding ring‐opened oligomers and polymers have been conducted in order to provide mechanistic insight into the processes that occur under the conditions of their thermal ring‐opening polymerisation (ROP) (300 °C). Thermolysis of dicarba[2]ferrocenophane rac‐[Fe(η5‐C5H4)2(CHPh)2] (rac‐14; 300 °C, 1 h) does not lead to thermal ROP. To investigate this system further, rac‐14 was heated in the presence of an excess of cyclopentadienyl anion, to mimic the postulated propagating sites for thermally polymerisable analogues. This afforded acyclic [(η5‐C5H5)Fe(η5‐C5H4)‐CH2Ph] (17) through cleavage of both a FeCp bond and also the CC bond derived from the dicarba bridge. Evidence supporting a potential homolytic CC bond cleavage pathway that occurs in the absence of ring‐strain was provided through thermolysis of an acyclic analogue of rac‐14, namely [(η5‐C5H5)Fe(η5‐C5H4)(CHPh)2‐C5H5] (15; 300 °C, 1 h), which also afforded ferrocene derivative 17. This reactivity pathway appears general for post‐ROP species bearing phenyl substituents on adjacent carbons, and consequently was also observed during the thermolysis of linear polyferrocenylethylene [Fe(η5‐C5H4)2(CHPh)2]n (16; 300 °C, 1 h), which was prepared by photocontrolled ROP of rac‐14 at 5 °C. This afforded ferrocene derivative [Fe(η5‐C5H4CH2Ph)2] (23) through selective cleavage of the H(Ph)CC(Ph)H bonds in the dicarba linkers. These processes appear to be facilitated by the presence of bulky, radical‐stabilising phenyl substituents on each carbon of the linker, as demonstrated through the contrasting thermal properties of unsubstituted linear trimer [(η5‐C5H5)Fe(η5‐C5H4)(CH2)2(η5‐C5H4)Fe(η5‐C5H4)(CH2)2(η5‐C5H4)Fe(η5‐C5H5)] (29) with a H2CCH2 spacer, which proved significantly more stable under analogous conditions. Evidence for the radical intermediates formed through CC bond cleavage was detected through high‐resolution mass spectrometric analysis of co‐thermolysis reactions involving rac‐14 and 15 (300 °C, 1 h), which indicated the presence of higher molecular weight species, postulated to be formed through cross‐coupling of these intermediates.
Single‐Step Gas‐Phase Polyperfluoroalkylation of Naphthalene Leads to Thermodynamic Products
Authors: San Long K. , Bukovsky Eric V. , Kuvychko Igor V. , Popov Alexey A. , Strauss Steven H. , Boltalina Olga V.
Published: March 2014

High‐temperature gas‐phase, solvent‐ and catalyst‐free reaction of naphthalene with an excess of RFI reagent (RFCF3, C2F5, n‐C3F7, and n‐C4F9) was used for the first time to produce a series of highly perfluoroalkylated naphthalene products NAPH(RF)n with n=2–5. Four 95+ % pure 1,3,5,7‐NAPH(RF)4 with RFCF3, C2F5, n‐C3F7, and n‐C4F9 were isolated using a simple chromatography‐free procedure. These new compounds were fully characterized by 19F and 1H NMR spectroscopy, X‐ray crystallography (for RFCF3 and C2F5), atmospheric‐pressure chemical ionization mass spectrometry, and cyclic and square‐wave voltammetry. DFT calculations confirm that the proposed synthesis yields the most stable isomers that have not been accessed by alternative preparation techniques.
Formal Total Synthesis of Kendomycin by Way of Alkyne Metathesis/Gold Catalysis
Authors: Hoffmeister Laura , Persich Peter , Fürstner Alois
Published: March 2014

In an attempt to study the ability of the latest generation of alkyne metathesis catalysts to process sterically hindered substrates, two different routes to the bacterial metabolite kendomycin (1) were explored. Whereas the cyclization of the overcrowded arylalkyne 39 and related substrates turned out to be impractical or even impossible, ring closure of the slightly relaxed diyne 45 was achieved in excellent yield under notably mild conditions with the aid of the molybdenum alkylidyne 2 endowed with triphenylsilanolate ligands. The resulting cycloalkyne 46 was engaged into a gold‐catalyzed hydroalkoxylation, which led to benzofuran 47 that had already previously served as a late‐stage intermediate en route to 1.
Dinuclear Ru–Aqua Complexes for Selective Epoxidation Catalysis Based on Supramolecular Substrate Orientation Effects
Authors: Di Giovanni Carlo , Poater Albert , Benet‐Buchholz Jordi , Cavallo Luigi , Solà Miquel , Llobet Antoni
Published: March 2014

Ru–aqua complex {[RuII(trpy)(H2O)]2(μ‐pyr‐dc)}+ is a powerful epoxidation catalyst for a wide range of linear and cyclic alkenes. High turnover numbers (TNs), up to 17000, and turnover frequencies (TOF), up to 24120 h−1 (6.7 s−1), have been obtained using PhIO as oxidant. This species presents an outstanding stereospecificity for both cis and trans olefins towards the formation of their corresponding cis and trans epoxides. In addition, it shows different reactivity to cis and trans olefins due to a substrate orientation supramolecular effect transmitted by its ligand scaffold. This effect together with the impressive reaction rates are rationalized using electrochemical techniques and DFT calculations.
Supercritical Carbon Dioxide Assisted Deposition of Fe3O4 Nanoparticles on Hierarchical Porous Carbon and Their Lithium‐Storage Performance
Authors: Wang Lingyan , Zhuo Linhai , Zhang Chao , Zhao Fengyu
Published: March 2014

A composite of highly dispersed Fe3O4 nanoparticles (NPs) anchored in three‐dimensional hierarchical porous carbon networks (Fe3O4/3DHPC) as an anode material for lithium‐ion batteries (LIBs) was prepared by means of a deposition technique assisted by a supercritical carbon dioxide (scCO2)‐expanded ethanol solution. The as‐synthesized Fe3O4/3DHPC composite exhibits a bimodal porous 3D architecture with mutually connected 3.7 nm mesopores defined in the macroporous wall on which a layer of small and uniform Fe3O4 NPs was closely coated. As an anode material for LIBs, the Fe3O4/3DHPC composite with 79 wt % Fe3O4 (Fe3O4/3DHPC‐79) delivered a high reversible capacity of 1462 mA h g−1 after 100 cycles at a current density of 100 mA g−1, and maintained good high‐rate performance (728, 507, and 239 mA h g−1 at 1, 2, and 5 C, respectively). Moreover, it showed excellent long‐term cycling performance at high current densities, 1 and 2 A g−1. The enhanced lithium‐storage behavior can be attributed to the synergistic effect of the porous support and the homogeneous Fe3O4 NPs. More importantly, this straightforward, highly efficient, and green synthetic route will definitely enrich the methodologies for the fabrication of carbon‐based transition‐metal oxide composites, and provide great potential materials for additional applications in supercapacitors, sensors, and catalyses.
Electrochemical Degradation of Carbamazepine in Aqueous Solutions – Optimization of Kinetic Aspects by Design of Experiments
Authors: Palo Patricia , Dominguez Joaquin R. , Sánchez‐Martín Jesús , González Teresa
Published: March 2014

Electrodegradation of simulated pharmaceutical wastewaters was performed and optimized according to response surface methodology. To this end, carbamazepine (CBZ) was used as a model compound and a design of experiments was planned for evaluating the influence of two main variables in the electrochemical process: initial CBZ concentration (in logarithm terms) and the current density. Target variable was an apparent first‐order kinetic constant (k) designed ad hoc. Interaction of variables was confirmed and an optimum k constant of 0.72 min−1 was obtained. CBZ was also removed from real wastewater matrices, such as urban wastewater or surface water from river and lake.
High‐Throughput Synthesis of Peptide α‐Thioesters: A Safety Catch Linker Approach Enabling Parallel Hydrogen Fluoride Cleavage
Authors: Brust Andreas , Schroeder Christina I. , Alewood Paul F.
Published: March 2014

Peptide α‐thioesters are fundamental building blocks in peptide and protein science, providing powerful tools for peptide medicinal chemistry. The application of peptide α‐thioesters in native chemical ligation reactions has enabled synthetic access to cysteine‐rich peptides and proteins, cyclic peptides as well as labeled and chemically modified biomolecules. An efficient high‐throughput synthesis of peptide α‐thioester building blocks would be beneficial for many medicinal chemical applications that require peptides and proteins. Herein we present a novel synthetic route to cysteine‐rich peptide α‐thioesters using a safety catch linker that enables a parallel synthetic strategy for chemical protein synthesis. ACP(68–75), bradykinin and dynorphin(1–13) were synthesized via Boc chemistry in their thioester form on a safety catch amide linker (SCAL), employing polystyrene‐ or poly(ethylene glycol)‐based resins, compartmentalized in tea bags. This compartmentalized resin/linker strategy facilitated a parallel hydrogen fluoride cleavage in which each peptide thioester was subsequently cyclized by native chemical ligation, demonstrating the utility of this approach. A naturally occurring bioactive cyclic peptide, the sunflower trypsin inhibitor SFTI‐1, was synthesized to demonstrate the viability of this method to access important peptide biomolecules.
Cystic pancreatic neuroendocrine tumors: The value of cytology in preoperative diagnosis
Authors: Morales‐Oyarvide Vicente , Yoon Won Jae , Ingkakul Thun , Forcione David G. , Casey Brenna W. , Brugge William R. , Fernández‐del Castillo Carlos , Pitman Martha B.
Published: March 2014

BACKGROUND

Cystic pancreatic neuroendocrine tumors (cPanNETs) account for 13% to 17% of PanNETs. Although the value of endoscopic ultrasound (EUS) imaging and cyst fluid analysis (CFA) in their preoperative diagnosis has been well described, limited information is available about the diagnostic role of cytology samples obtained from fine‐needle aspiration (FNA).

METHODS

Cytopathology records between 1992 and 2013 were searched for all reports of cysts interpreted as PanNET. Patient demographics, clinical and radiologic information, CFA, histopathology, and cytopathology findings were recorded. Performance characteristics of cytology and EUS for the accurate diagnosis of cPanNET were calculated.

RESULTS

In total, 35 FNAs from 33 patients with cPanNETs were identified, and 34 EUS were performed. Cytology made a specific diagnosis of a cPanNET in 71% of the biopsies compared with a specific diagnosis by EUS in 38% of cases. An interpretation of suspicious for cPanNET was given in 77% of cases by cytology and in 47% by EUS. Cytology identified 86% of the lesions as high‐risk pancreatic cysts compared with 56% by EUS. Diagnostic morphology was present on both cytology and cell block preparations in 60% of aspirates, on cytology only in 20%, and on cell block only in 20%. CFA was performed on 51% cyst fluids. All cysts but 1 revealed low carcinoembryonic antigen levels (range, 0.2 to >500 ng/mL; mean, 29.5 ng/mL), and amylase levels were <500 U/L in all but 2 cases (range, 16‐1493 U/L; mean, 205 U/L).

CONCLUSIONS

Cytology is the most accurate test for preoperative diagnosis of cPanNETs. EUS is insufficiently accurate for independent diagnosis, and carcinoembryonic antigen and amylase analyses are noncontributory. Cancer (Cancer Cytopathol) 2014;122:435–444. © 2014 American Cancer Society.
Molecular Theory of Phase Separation in Nematic Liquid Crystals Doped with Spherical Nanoparticles
Authors: Osipov Mikhail A. , Gorkunov Maxim V.
Published: March 2014

A molecular‐statistical theory is developed, which enables one to describe the nematic–isotropic phase transition in liquid crystals doped with spherical nanoparticles taking into account the effects of phase separation. It has been shown that in the case of strong interaction between nanoparticles and mesogenic molecules the nematic nanocomposite possesses a number of unexpected properties. In particular, the nematic–isotropic co‐existence region appears to be very broad, and the system either undergoes a direct transition from the isotropic phase into the phase‐separated state, or undergoes the transition into the homogeneous nematic phase first and then phase‐separates at a lower temperature. Phase separation does not occur at all if the concentration of the nanoparticles is sufficiently low, and in some cases it takes place only within a finite region of nanoparticle concentration. A number of temperature–concentration phase diagrams is presented and the molar fractions of nanoparticles in the co‐existing isotropic and nematic phases are calculated numerically as functions of temperature.
A Time‐Dependent DFT Study of the Absorption and Fluorescence Properties of Graphene Quantum Dots
Authors: Zhao Meilian , Yang Feng , Xue Ying , Xiao Dan , Guo Yong
Published: March 2014

Absorption and fluorescence spectra of graphene quantum dots (GQDs) have been computed by using time‐dependent density functional theory (TDDFT). Different functionals, including PBE, TPSSh, B3LYP, PBE0, CAM‐B3LYP, and LC‐ωPBE, have been tested and B3LYP/6‐31G(d) has been proven to be the most accurate method for our work. The bulk solvent effects of toluene and dichloromethane have been assessed by using the polarizable continuum model (PCM). The absorption wavelength of GQDs in solvents is red‐shifted compared with that in the gas phase. Edge functionalization effects analysis shows that a small number of substituted groups on GQDs induce a small redshift whereas a large redshift occurs when the edges of GQDs are all decorated. Little difference in the fluorescent emission was observed in solvents and in the gas phase. Molecular orbital transition and transition density matrix analysis have been performed. The electronic transition mainly occurs in the middle part of the structure of C132. The strong absorption of C132 corresponds to a S0→S3 transition and the fluorescence emission is ascribed to a S1→S0 transition, which indicates that Kasha’s rule is obeyed.
Characterization and Distribution of Poly(3‐hexylthiophene) Phases in an Annealed Blend Film
Authors: Hu Rong , Zhang Wei , Wang Peng , Qin Yujun , Liang Ran , Fu Li‐Min , Zhang Jian‐Ping , Ai Xi‐Cheng
Published: March 2014

The characteristic absorption spectra of three kinds of phases, the isolated, ordered, and disordered phases, in a solvent‐vapor annealed poly(3‐hexylthiophene)/[6,6]‐phenyl‐C61‐butyric acid methyl ester (P3HT/PCBM) blend film were studied by means of spectroelectrochemistry (SEC) and time‐resolved absorption spectroscopy (TAS). The results reveal that the content of three phases are 12 % isolated, 37 % ordered, and 51 % disordered for the annealed P3HT neat film, and 25 % isolated, 31 % ordered, and 44 % disordered for the annealed P3HT/PCBM blend film. The vertical distribution of the different phases in the blend film was studied by SEC, and the results show that the ordered and isolated phases are mainly distributed in the top and in the bottom of the annealed films, respectively, while the disordered phase is mainly distributed in the middle and the bottom of the films.
Photophysical Evidence of Charge‐Transfer‐Complex Pairs in Mixed‐Linker 5‐Amino/5‐Nitroisophthalate CAU‐10
Authors: Ferrer Belén , Alvaro Mercedes , Baldovi Hermenegildo G. , Reinsch Helge , Stock Norbert
Published: March 2014

The photochemistry of two isostructural metal–organic frameworks based on 5‐amino/5‐formamidoisophthalate (CAU‐10‐NH2/NHCHO) or mixed‐linker 5‐amino/5‐formamido‐ and 5‐nitroisophthalate (CAU‐10‐NO2/NH2/NHCHO) has been studied using laser flash photolysis. 355 nm excitation of CAU‐10‐NH2/NHCHO leads to a transient absorption spectrum characterized by a broad continuous absorption from 380 to 800 nm that was attributed to the presence of holes (440 nm) and electrons (600 nm) based on iPrOH and N2O quenching, respectively. In contrast, no transients were observed for the isostructural mixed‐linker CAU‐10‐NO2/NH2/NHCHO, data that is compatible with the uniform distribution of linkers 5‐amino/5‐formamido/5‐nitroisophthalate as charge‐transfer complex pairs. The same effect of quenching of 5‐aminoisophthalate transients by 5‐nitroisophthalate was also observed in aqueous solution (pH 9) but with much lower strength. Using a simple Stern–Volmer formalism allowed the estimation of the interaction of 5‐aminoisophthalate with 5‐nitroisophthalate in MOF to be 5.2×104 times stronger than in the aqueous phase.
A Facile, Template‐Free Synthesis of AgCl Hierarchical Architectures: Precursors of Highly Efficient Visible‐Light Plasmonic Photocatalysts of Ag@AgCl
Authors: Wang Yu , Chen Gang , Di Andi , Xu Haiming
Published: March 2014

This paper describes a facile, template‐free synthesis of AgCl hierarchical structures by a gas–liquid interfacial method and the morphology of AgCl (microrods or film) can be conveniently varied or controlled by changing the solvents of AgNO3 without using any surfactants. The AgCl composites were then photoreduced to form highly efficient visible‐light plasmonic photocatalyst Ag@AgCl nanostructures. SEM, XRD, X‐ray photoelectron spectroscopy, and UV/Vis diffuse reflectance spectroscopy were used to characterize the obtained product. The photocatalytic activity of the obtained product was evaluated by the photodegradation of methyl orange pollutant under visible‐light irradiation, and it was found that Ag@AgCl microrods exhibited high visible‐light photocatalytic activity and good stability.
Oncocytic lipoadenoma of the parotid gland: Cytological findings and differential diagnosis on fine‐needle aspiration
Authors: Ashraf Mohammad Javad , Azarpira Negar , Anbardar Mohammad Hossein , Hashemi Seyed Basir
Published: March 2014

Oncocytic lipoadenoma is a rare benign neoplastic lesion of salivary gland. To the best of our knowledge, the detailed cytomorphological findings were described only in two cases. We are reporting a 56‐year‐old woman who presented with 1‐year history of right parotid gland mass. Cytologic examination revealed tight clusters of bland looking oncocytic ductal cells with few aggregates of mature adipose tissue in a lipoid background and a benign oncocytic tumor of parotid gland was rendered. Histologically, a tumor with islands of oncocytic epithelial cells admixed with abundant mature adipose tissue was identified. Oncocytic lipoadenoma despite its rarity should be considered in the differential diagnosis of salivary gland fine‐needle aspirations containing oncocytes especially those which are accompanied by mature adipose tissue and lipoid background. Diagn. Cytopathol. 2015;43:72–74. © 2014 Wiley Periodicals, Inc.
Juvenile ossifying fibroma diagnosed on fine needle aspiration cytology: A diagnostic challenge
Authors: Goyal Surbhi , Sharma Sonal , Arora Vipin
Published: March 2014

Preoperative diagnosis of jaw lesions is not always possible on the basis of clinico‐radiological findings alone and needs to be confirmed before attempting any surgical intervention. Fibro‐osseous lesions of the jaw comprise a spectrum of diseases which include cement‐osseous dysplasia, fibrous dysplasia, and ossifying fibroma. The cytomorphological distinction between these individual entities is difficult. We present a case of maxillary fibro‐osseous lesion in an adolescent girl diagnosed and categorized as juvenile ossifying fibroma preoperatively on cytology and confirmed on histopathology. Although aspirates are usually paucicellular in fibro‐osseous lesions, certain cytological features if present in cellular cytosmears can offer further categorization and a definitive diagnosis may be possible in light of clinico‐radiological correlation. Diagn. Cytopathol. 2015;43:75–79. © 2014 Wiley Periodicals, Inc.
Cytomorphological features of atypical teratoid/rhabdoid tumor: An account of 12 years' experience
Authors: Güner Güneş , Önder Sevgen , Söylemezoğlu Figen
Published: March 2014

Atypical teratoid rhabdoid tumor (AT/RT), an aggressive neoplasm mostly affecting young children, is characterized by rhabdoid cells together with epithelial, mesenchymal and primitive differentiation. Diagnosing AT/RT in intraoperative consultation and cerebrospinal fluid (CSF) samples may therefore pose problems. Fourteen immunohistochemically proven AT/RTs diagnosed between 2000 and 2012 were collected. Material consisted of squash smears prepared during intraoperative consultation (thirteen) and CSF smears (three). MGG‐stained CSF smears and H&E stained squash smears were reviewed by a neuropathologist and a cytopathologist. The intraoperative diagnoses were based on squash preparations and 3 out of 13 were consistent with AT/RT, 4 were considered medulloblastoma/primitive neuroectodermal tumors (PNET), 3 were deferred to paraffin section for tumor typing, and another 3 were misdiagnosed as ependymoma, germinoma and malignant glioma. Morphological assessment of intraoperative squash preparations showed that AT/RTs can have a mixture of pseudopapillary and diffuse smearing patterns. Cytomorphologic features consisted of characteristic rhabdoid cells (8/9); primitive appearing cells with a high nuclear to cytoplasmic ratio (7/9); bi‐/multinucleated cells (3/9); rare necrosis/apoptosis and mitoses. Three CSF smears showed high cellularity and inclusion‐bearing large cells. These cells are characterized by reniform/oval, eccentrically placed nuclei with cytoplasmic perinuclear light stained areas which are not seen in intraoperative squash preparations. Differential diagnosis of AT/RT in cytology involves medulloblastoma/PNET, ependymoma, glioma and germinoma among all others. Overlapping features of AT/RT with entities in differential diagnosis are discussed with a special emphasis of rhabdoid cells being the strongest feature to aid in reaching the diagnosis of AT/RT. Diagn. Cytopathol. 2014;42:856–862. © 2014 Wiley Periodicals, Inc.
Natural reversal of left‐right gut/gonad asymmetry in C. elegans males is independent of embryonic chirality
Authors: Callander Davon C. , Alcorn Melissa R. , Birsoy Bilge , Rothman Joel H.
Published: March 2014

Anatomical left‐right (L/R) asymmetry in C. elegans is established in the four‐cell embryo as a result of anteroposterior skewing of transverse mitotic spindles with a defined handedness. This event creates a chiral embryo and ultimately an adult body plan with fixed L/R positioning of internal organs and components of the nervous system. While this “dextral” configuration is invariant in hermaphrodites, it can be reversed by physical manipulation of the early embryo or by mutations that interfere with mitotic spindle orientation, which leads to viable, mirror‐reversed (sinistral) animals. During normal development of the C. elegans male, the gonad develops on the right of the midline, with the gut bilaterally apposed on the left. However, we found that in males of the laboratory N2 strain and Hawaiian (“Hw”) wild isolate, the gut/gonad asymmetry is frequently reversed in a temperature‐dependent manner, independent of normal embryonic chirality. We also observed sporadic errors in gonad migration occurring naturally during early larval stages of these and other wild strains; however, the incidence of such errors does not correlate with the frequency of L/R gut/gonad reversals in these strains. Analysis of N2/Hw hybrids and recombinant inbred advanced intercross lines (RIAILs) indicate that the L/R organ reversals are likely to result from recessively acting variations in multiple genes. Thus, unlike the highly reproducible L/R asymmetries of most structures in hermaphrodites, the L/R asymmetry of the male C. elegans body plan is less rigidly determined and subject to natural variation that is influenced by a multiplicity of genes. genesis 52:581–587, 2014. © 2014 Wiley Periodicals, Inc.
Symmetry breakage in the frog Xenopus: Role of Rab11 and the ventral‐right blastomere
Authors: Tingler Melanie , Ott Tim , Tözser Janos , Kurz Sabrina , Getwan Maike , Tisler Matthias , Schweickert Axel , Blum Martin
Published: March 2014

Vertebrates display asymmetric arrangements of inner organs such as heart and stomach. The Nodal signaling cascade in the left lateral plate mesoderm in all cases directs asymmetric morphogenesis and placement during organogenesis. Mechanisms that lead up to left‐asymmetric Nodal induction seem to differ between the vertebrates. Cilia produce a leftward extracellular fluid flow in zebrafish, medaka, mouse, rabbit, and Xenopus embryos during neurulation. In Xenopus, earlier asymmetric cues were described. Some, such as Rab11, apparently act in the zygote. Others were efficiently manipulated in ventral‐right cells at the four‐cell stage, a lineage presumably independent of the ciliated gastrocoel roof plate (GRP) during neurulation. Here, we show that one‐ and four‐cell manipulations of Rab11 showed equal low efficiencies of left–right disturbances. We also reevaluated the lineage of the GRP. By tracing back future ciliated cells from the gastrula to the four‐cell stage, we show that ventral cells contribute to ciliated sensory cells at the border of the GRP. Knockdown of the Nodal inhibitor Coco in the ventral right lineage resulted in embryos with ectopic right‐sided Nodal and Pitx2c expression. Together, these experiments support a cilia‐based mechanism of symmetry breakage in the frog Xenopus. genesis 52:588–599, 2014. © 2014 Wiley Periodicals, Inc.
Emotion regulation difficulties in anorexia nervosa before and after inpatient weight restoration
Authors: Haynos Ann F. , Roberto Christina A. , Martinez Margaret A. , Attia Evelyn , Fruzzetti Alan E.
Published: March 2014

Objective

This study examined: (1) changes in emotion regulation difficulties in underweight inpatients with anorexia nervosa (AN) following weight restoration, (2) differences in emotion regulation between AN subtypes at acute and weight‐restored stages of illness.

Method

Repeated measure analyses of variance examined changes in scores on the Difficulties in Emotion Regulation Scale (DERS; Gratz and Roemer, J Psychopathol Behav Assess, 26, 41–54, 2004) and other clinical variables in a group of inpatients with AN from hospital admission (N = 65) to weight restoration (N = 51). Correlations between BMI and DERS scores at both time points were examined. Emotion regulation difficulties were compared between individuals with AN, restricting type (AN‐R) and AN, binge/purge type (AN‐BP) at both time points using multivariate analysis of covariance.

Results

All clinical variables, except for the DERS, significantly improved with weight restoration (p < .001). There were no associations between BMI and DERS prior to or after weight restoration and AN subtypes did not significantly differ in emotion regulation difficulties.

Discussion

Unlike other clinical variables, emotion regulation difficulties in AN did not improve with weight restoration. In addition, both subtypes of AN appear to have similar difficulties with emotion regulation. The treatment of AN might be enhanced by focusing on improving emotion regulation abilities. © 2014 Wiley Periodicals, Inc. Int J Eat Disord 2014; 47:888–891
Increased genetic divergence between two closely related fir species in areas of range overlap
Authors: Wang Jing , Abbott Richard J. , Ingvarsson Pär K. , Liu Jianquan
Published: March 2014

Because of introgressive hybridization, closely related species can be more similar to each other in areas of range overlap (parapatry or sympatry) than in areas where they are geographically isolated from each other (allopatry). Here, we report the reverse situation based on nuclear genetic divergence between two fir species, Abies chensiensis and Abies fargesii, in China, at sites where they are parapatric relative to where they are allopatric. We examined genetic divergence across 126 amplified fragment length polymorphism (AFLP) markers in a set of 172 individuals sampled from both allopatric and parapatric populations of the two species. Our analyses demonstrated that AFLP divergence was much greater between the species when comparisons were made between parapatric populations than between allopatric populations. We suggest that selection in parapatry may have largely contributed to this increased divergence.
The impact of kidney function on outcomes following high risk myocardial infarction: findings from 27 610 patients
Authors: Moukarbel George V. , Yu Zi‐Fan , Dickstein Kenneth , Hou Yingxin (Rachel) , Wittes Janet T. , McMurray John J. V. , Pitt Bertram , Zannad Faiez , Pfeffer Marc A. , Solomon Scott D.
Published: March 2014

Aims

Renal dysfunction is associated with poor cardiovascular outcome. We investigated the relationship of kidney function and long‐term cardiovascular outcomes in patients with high risk myocardial infarction.

Methods and results

We studied 27 610 patients from four randomized trials of acute myocardial infarction complicated by heart failure and/or LV dysfunction (LVEF ≤40%). Two trials excluded patients with serum creatinine ≥2.5 mg/dL. Patients were grouped by estimated glomerular filtration rate (eGFR) using the four‐component Modification of Diet in Renal Disease equation. We used adjusted Cox proportional hazard models to compare mortality and composite cardiovascular events among eGFR groups. Median follow‐up was 23 months. The eGFR was approximately normally distributed, with a mean ± SD of 69.1 ± 20.2 mL/min/1.73 m2. Co‐morbidities were more prevalent with lower eGFR. The risk of death or composite outcome of cardiovascular death, myocardial infarction, stroke, or heart failure hospitalization increased with declining eGFR. Below 75 mL/min/1.73 m2, each 10 unit reduction of eGFR was associated with an adjusted hazard ratio for death of 1.13 (95% confidence interval, 1.11–1.15) and composite cardiovascular outcome of 1.09 (95% confidence interval, 1.08–1.10). Older patients (≥75 years) with low LVEF (<30%) had a higher incidence of mortality and adverse cardiovascular events across eGFR categories.

Conclusions

Reduced eGFR is strongly and independently associated with poor cardiovascular outcome following high risk myocardial infarction. In these patients, the combination of older age and poor LV systolic function is associated with increased risk of adverse events.
Preparation of Ag‐Modified (B,P)‐Codoped TiO2 Hollow Spheres with Enhanced Photocatalytic Activity
Authors: Yu Shuohan , Li Bin , Luo Yidan , Dong Lihui , Fan Minguang , Zhang Feiyue
Published: March 2014

Invited for the cover of this issue is the group of Bin Li at Guangxi University, China. The cover image shows that the Ag metal on the surface of the TiO2 photocatalyst enhances the separation of the photoelectrons from the photogenerated holes, delaying the recombination of photoelectron–hole pairs, which improves the photocatalytic activity of TiO2 hollow spheres.
Society matters: The mediational role of social recognition in the relationship between victimization and life satisfaction among gay men
Authors: Bachmann Anne S. , Simon Bernd
Published: March 2014

This article examines the role of social recognition in the relationship between gay men's victimization and their life satisfaction. Using a comprehensive catalog of victimization, we obtained empirical evidence that strongly suggests that victimization negatively affects gay men's life satisfaction and that this relationship is mainly mediated by a perceived lack of social recognition in society. In addition, although active involvement in the gay community served as a coping mechanism, concealment of one's sexual identity played no role in the victimization–life satisfaction relationship, neither as a coping mechanism nor as a competing mediator. The mediational role of societal recognition underlines the importance of the symbolic meaning of victimization. Copyright © 2014 John Wiley & Sons, Ltd.
Construction and Application of an Electrochemical Sensor for Simultaneous Determination of Cd(II), Cu(II) and Hg(II) in Water and Foodstuff Samples
Authors: Afkhami Abbas , Moosavi Razieh , Madrakian Tayyebeh , Keypour Hassan , Ramezani‐Aktij Ameneh , Mirzaei‐Monsef Misagh
Published: March 2014

By incorporation of synthesized magnetite nanoparticles (Fe3O4 NPs) coated with a new Schiff base into carbon paste electrode, a novel modified electrode was constructed for simultaneous determination of ultra trace amounts of Cd(II), Cu(II) and Hg(II). The complexation reaction of Schiff base with metal ions was studied spectrophotometrically. Under optimal conditions a detection limit of 0.20, 0.90 and 1.00 ng mL−1 for Cd(II), Cu(II) and Hg(II), respectively, was obtained. We take the advantages of the proposed method for simple, rapid, sensitive and selective simultaneous determination of trace amounts of hazardous Cd(II), Cu(II) and Hg(II) in water and foodstuff samples.
Classification of Spanish white wines using their electrophoretic profiles obtained by capillary zone electrophoresis with amperometric detection
Authors: Arribas Alberto Sánchez , Martínez‐Fernández Marta , Moreno Mónica , Bermejo Esperanza , Zapardiel Antonio , Chicharro Manuel
Published: March 2014

A method was developed for the simultaneous detection of eight polyphenols (t‐resveratrol, (+)‐catechin, quercetin and p‐coumaric, caffeic, sinapic, ferulic, and gallic acids) by CZE with electrochemical detection. Separation of these polyphenols was achieved within 25 min using a 200 mM borate buffer (pH 9.4) containing 10% methanol as separation electrolyte. Amperometric detection of polyphenols was carried out with a glassy carbon electrode (GCE) modified with a multiwalled carbon nanotubes (CNT) layer obtained from a dispersion of CNT in polyethylenimine. The excellent electrochemical properties of this modified electrode allowed the detection and quantification of the selected polyphenols in white wines without any pretreatment step, showing remarkable signal stability despite the presence of potential fouling substances in wine. The electrophoretic profiles of white wines, obtained using this methodology, have proven to be useful for the classification of these wines by means of chemometric multivariate techniques. Principal component analysis and discriminant analysis allowed accurate classification of wine samples on the basis of their grape varietal (verdejo and airén) using the information contained in selected zones of the electropherogram. The utility of the proposed CZE methodology based on the electrochemical response of CNT‐modified electrodes appears to be promising in the field of wine industry and it is expected to be successfully extended to classification of a wider range of wines made of other grape varietals.