bluuebunny/crossref_metadata_2025 huggingface dataset:
Pyrolyzed Polyaniline–Graphene Nanosheets with Enhanced Lithium‐Storage Properties: Preparation and Characterization
Authors: Wang Yong‐Chen , Zhu Bi‐Yu , Ni Jiang‐Feng , Zhang Li , Wang Hai‐Bo , Gao Li‐Jun
Published: March 2014

Pyrolyzed polyaniline–graphene nanosheets (PA–GNS) are examined as a lithium‐storage material. The PA–GNS composite is synthesized through heat treatment of polyaniline–graphite oxide precursors under a H2/Ar atmosphere at 850 °C. Scanning and transmission electron microscopies, X‐ray diffraction, Raman spectroscopy, and X‐ray photoelectron spectroscopy are employed to characterize the prepared PA–GNS composite in comparison with pristine graphene nanosheets (GNS). Galvanostatic charge/discharge experiments show that PA–GNS exhibits an improved rate and cycle capability at both 25 and 55 °C. It is also found from electrical resistivity tests and electrochemical impedance spectroscopy measurements that the PA–GNS composite demonstrates a higher vertical electronic conductivity and lower charge‐transfer resistance than GNS, and it is concluded that modifying GNS with pyrolyzed polyaniline is an effective way to enhance the rate capability and cyclability of GNS.
Evidence of Facilitated Electron Transfer on Hydrogenated Self‐Doped TiO2 Nanocrystals
Authors: Minguzzi Alessandro , Sánchez‐Sánchez Carlos M. , Gallo Alessandro , Montiel Vicente , Rondinini Sandra
Published: March 2014

TiO2 nanocrystals are widely used as semiconductor photocatalysts, despite their limited sunlight absorption. The hydrogenation of TiO2 has recently been proposed as a promising new method for enhancing its solar‐driven photocatalytic activity. But, the ability of this hydrogenated TiO2 to transfer electrons across the interface has not been studied in detail. For this reason, the electrochemical properties of hydrogenated self‐doped TiO2−x nanocrystals are studied and compared to commercial anatase TiO2 nanocrystals. Here we use cyclic voltammetry (CV) and scanning electrochemical microscopy (SECM) as tools to characterize the semiconductors and, in particular, to evaluate their reactivity towards redox species in solution. CV is used to evaluate the doping level; we propose the co‐presence of permanent defects, induced by the hydrogenation reductive treatment, as well as temporary ones, induced electrochemically. By using ferrocenemethanol as the redox‐active species, SECM, in a substrate/tip configuration, demonstrates that the electron transfer is facilitated on hydrogenated self‐doped TiO2−x by a potential‐shift of approximately 0.3–0.4 V.
Heavy‐Atom Tunneling in the Ring Opening of a Strained Cyclopropene at Very Low Temperatures
Authors: Ertelt Melanie , Hrovat David A. , Borden Weston Thatcher , Sander Wolfram
Published: March 2014

The highly strained 1H‐bicyclo[3.1.0]‐hexa‐3,5‐dien‐2‐one 1 is metastable, and rearranges to 4‐oxacyclohexa‐2,5‐dienylidene 2 in inert gas matrices (neon, argon, krypton, xenon, and nitrogen) at temperatures as low as 3 K. The kinetics for this rearrangement show pronounced matrix effects, but in a given matrix, the reaction rate is independent of temperature between 3 and 20 K. This temperature independence means that the activation energy is zero in this temperature range, indicating that the reaction proceeds through quantum mechanical tunneling from the lowest vibrational level of the reactant. At temperatures above 20 K, the rate increases, resulting in curved Arrhenius plots that are also indicative of thermally activated tunneling. These experimental findings are supported by calculations performed at the CASSCF and CASPT2 levels by using the small‐curvature tunneling (SCT) approximation.
Exploring the Synthesis of a New Group of Chiral Ammonium Salts with Specific Configurations at the Stereogenic Nitrogen Centers
Authors: Eckert Prisca K. , Golz Christopher , Degen Patrick , Werner Cornelia , Rehage Heinz , Strohmann Carsten
Published: March 2014

A group of new chiral dications with a fixed, specific configuration at the stereogenic nitrogen center was created. Stereoselective synthesis and recrystallization give the diastereomerically and enantiomerically pure dications, including a chiral amphiphile with surface‐active properties.
Characterizing the ultrastructure of primary ciliary dyskinesia transposition defect using electron tomography
Authors: Burgoyne Thomas , Lewis Amy , Dewar Ann , Luther Pradeep , Hogg Claire , Shoemark Amelia , Dixon Mellisa
Published: March 2014

Primary ciliary dyskinesia is an autosomal recessive disorder affecting the motility of cilia. There are a range of ultrastructural ciliary defects that lead to associated clinical symptoms including ineffective mucus clearance, reduced lung function, infertility, and left‐right isomerism. Mutations in radial spoke head proteins are a known cause of primary ciliary dyskinesia. Ultrastructually these defects are identified by a portion of cilia lacking a central pair and transposed outer microtubular doublets. We have repeatedly observed an intermittent loss of the central pair in patients with a transposition defect. To further understand the central pair changes in these radial spoke head mutations we employ electron tomography, a high resolution electron microscope technique, to elucidate in three dimensions the ultrastructural arrangements caused by mutation of the RSPH4A gene. We thereby provide an explanation of the structures observed by conventional electron microscopy studies. We demonstrate that the central pair can be present within the cilium. In some cilia, the central pair rotates at the base of the axoneme. We propose that it is this rotation that gives rise to an intermittent appearance of the central pair when viewed under conventional electron microscopy. We discuss the potential causes and consequences of these findings. © 2014 Wiley Periodicals, Inc.
The actin cytoskeleton in rapid steroid hormone actions
Authors: Stournaras Christos , Gravanis Achilles , Margioris Andrew N. , Lang Florian
Published: March 2014

Early actin cytoskeleton reorganization is an important regulatory step of membrane‐initiated, non‐genomic steroid hormone actions. Specific intracellular signaling cascades control the rapid alterations of actin polymerization in a variety of cell models. Moreover, actin remodeling is a decisive component in the signaling of hormone‐induced early and late cellular responses. This article briefly summarizes the current knowledge on the steroid hormone‐induced early actin cytoskeleton rearrangements. It focuses on the current progress to characterize the glucocorticoid‐ and androgen‐initiated, tissue‐specific actin signaling pathways and discusses the plethora of cellular responses that are regulated by the early actin redistribution. It also provides insights into the potential clinical significance of actin dynamics and actin‐specific molecular signaling for nongenomic steroid hormone actions on tumor cells. © 2014 Wiley Periodicals, Inc.
Delivery of Suramin as an Antiviral Agent through Liposomal Systems
Authors: Mastrangelo Eloise , Mazzitelli Stefania , Fabbri Jacopo , Rohayem Jacques , Ruokolainen Janne , Nykänen Antti , Milani Mario , Pezzullo Margherita , Nastruzzi Claudio , Bolognesi Martino
Published: March 2014

Norovirus RNA‐dependent RNA polymerase (RdRp) is a promising target enzyme for the development of new antiviral drugs. Starting from the crystal structure of norovirus RdRp, we had previously performed an in silico docking search using a library of low‐molecular‐weight compounds that enabled us to select molecules with predicted enzyme inhibitory activity. Among these, the polysulfonated naphthylurea suramin proved to inhibit in vitro both murine and human norovirus polymerases, with IC50 values in the low micromolar range. The negatively charged inhibitor, however, displayed poor cell permeability in cell‐based experiments. Therefore, we produced different suramin‐loaded liposome formulations and evaluated their activities in cell‐based assays using murine norovirus cultivated in RAW 264.7 macrophages, as a model for norovirus genus. The results obtained show that suramin, when delivered through liposomes, can effectively inhibit murine norovirus replication.
Synthesis and DNA Cleavage Activity of Bis‐3‐chloropiperidines as Alkylating Agents
Authors: Zuravka Ivonne , Roesmann Rolf , Sosic Alice , Wende Wolfgang , Pingoud Alfred , Gatto Barbara , Göttlich Richard
Published: March 2014

Nitrogen mustards are an important class of bifunctional alkylating agents routinely used in chemotherapy. They react with DNA as electrophiles through the formation of highly reactive aziridinium ion intermediates. The antibiotic 593A, with potential antitumor activity, can be considered a naturally occurring piperidine mustard containing a unique 3‐chloropiperidine ring. However, the total synthesis of this antibiotic proved to be rather challenging. With the aim of designing simplified analogues of this natural product, we developed an efficient bidirectional synthetic route to bis‐3‐chloropiperidines joined by flexible, conformationally restricted, or rigid diamine linkers. The key step involves an iodide‐catalyzed double cyclization of unsaturated bis‐N‐chloroamines to simultaneously generate both piperidine rings. Herein we describe the synthesis and subsequent evaluation of a series of novel nitrogen‐bridged bis‐3‐chloropiperidines, enabling the study of the impact of the linker structure on DNA alkylation properties. Our studies reveal that the synthesized compounds possess DNA alkylating abilities and induce strand cleavage, with a strong preference for guanine residues.
Thyroid “Atypia of undetermined significance” with nuclear atypia has high rates of malignancy and BRAF mutation
Authors: Park Hyo Jin , Moon Jae Hoon , Yom Cha Kyong , Kim Kyu Hyung , Choi June Young , Choi Sang Il , Ahn Soon‐Hyun , Jeong Woo‐Jin , Lee Won Woo , Park So Yeon
Published: March 2014

BACKGROUND

“Atypia of undetermined significance” (AUS) in the Bethesda System for Reporting Thyroid Cytopathology is a heterogeneous category for cases that cannot be easily classified into benign, suspicious, or malignant. This study evaluated whether cytomorphology‐based subcategorization could better predict the malignancy risk in cases designated as AUS, and how the subcategories correlated with BRAF mutation status in thyroid fine‐needle aspirates (FNA).

METHODS

Of 3589 cases of thyroid FNA diagnosed at the authors' institution in Seongnam, Korea, from January 2010 to December 2011, 331 cases of AUS were reviewed and subcategorized based on cytomorphological features, including nuclear atypia (NA), microfollicle formation (MF), Hürthle cell change (HC), and others (O). The malignancy rate of each subcategory was calculated using cases with histologic follow‐up. Pyrosequencing was conducted to detect BRAF mutations.

RESULTS

Malignancy was histologically proven in 23.3% (77 of 331) of cases diagnosed as AUS. In cytomorphology‐based subcategories, the rate of malignancy was 30.8% (66 of 214) for AUS‐NA, 14.5% (8 of 55) for AUS‐O, 4.8% (2 of 42) for AUS‐MF, and 5% (1 of 20) for AUS‐HC. The BRAF V600E mutation was found in 40% (48 of 120) of AUS‐NA, 30.8% (4 of 13) of AUS‐HC, 6.7% (1 of 15) of AUS‐O, and 2.8% (1 of 35) of AUS‐MF.

CONCLUSIONS

The AUS‐NA subcategory was associated with the highest risk of malignancy and the greatest frequency of BRAF V600E (substitution of valine to glutamic acid at position 600) mutation. These findings suggest that subcategorization of AUS by cytomorphology and BRAF V600E mutation status is important for predicting the risk of malignancy. Cancer (Cancer Cytopathol) 2014;122:512–520. © 2014 American Cancer Society.
Large Magnetocaloric Effect, Moment, and Coercivity Enhancement after Coating Ni Nanoparticles with Ag
Authors: Srinath Sanyadanam , Poddar Pankaj , Das Raja , Sidhaye Deepti , Prasad Bhagavatula Lakshmi Vara , Gass James , Srikanth Hariharan
Published: March 2014

We observe a large magnetocaloric effect in monodisperse Ni and NicoreAgshell nanoparticles in the superparamagnetic region. The organically passivated Ni nanospheres show a large magnetic entropy change of 0.9 J kg−1 K for a 3 T magnetic field change. In comparison to the surfactant‐coated Ni nanoparticles, the NicoreAgshell nanoparticles show an enhanced coercivity, magnetization, and magnetocaloric effect (1.3 kg K for a 3 T magnetic field change). The coercivity at 10 K increases from 360 Oe for Ni nanoparticles to nearly 610 Oe for NicoreAgshell particles. This large enhancement is attributed to the enhanced inter‐particle interaction, which is mediated by the metallic shell, over the relatively weaker dipolar interaction in the surfactant‐coated Ni nanoparticles, and to modification of the surface spin structure.
Role of Edge Geometry and Magnetic Interaction in Opening Bandgap of Low‐Dimensional Graphene
Authors: Zhu Yongfu , Lian Jianshe , Jiang Qing
Published: March 2014

By using a size‐dependent cohesive energy formula for two‐dimensional coordination materials, the bandgap openings of ideal graphene quantum dots (GQDs) and nanoribbons (GNRs) have been investigated systematically regarding dimension, edge geometry, and magnetic interaction. Results demonstrate that the bandgap openings in GQDs can be dominated by the change of atomic cohesive energy. Relative to zigzag GQDs, the openings in the armchair ones are more substantial, attributed to its edge instability. The change of cohesive energy can also lead to bandgap openings in zigzag and armchair GNRs. The contribution from the interedge magnetic interaction in zigzag GNRs is negligible, while the cohesive‐energy induced openings in armchair GNRs can oscillate according to the so‐called full‐wavelength effect, depending on the width. The model prediction provides physicochemical insight into the bandgap openings in graphene.
Predictors of changes in health status between and within patients 12 months post left ventricular assist device implantation
Authors: Brouwers Corline , de Jonge Nicolaas , Caliskan Kadir , Manintveld Olivier , Young Quincy‐Robyn , Kaan Annemarie , Kealy Jennifer , Denollet Johan , Pedersen Susanne S.
Published: March 2014

Background

Improving patient‐reported outcomes (e.g. health status) has become an important goal in left ventricular assist device (LVAD) therapy, in addition to reducing mortality and morbidity. We examined predictors of changes in health status scores between and within patients 12 months post LVAD implantation.

Methods

Health status [Kansas City Cardiomyopathy Questionnaire (KCCQ); Short‐Form 12 (SF‐12)] were assessed at 3–4 weeks after implantation, and at 3, 6 and 12 months follow up in 54 LVAD patients (74% men; mean age 54 ± 9 years).

Results

Patients experienced significant improvements in health status between baseline and 3 months follow‐up as assessed by the KCCQ (clinical summary score: F = 33.49, P < 0.001; overall summary score: F = 31.13, P < 0.001) and the SF‐12 (physical component score: F = 31.59, P < 0.001; mental component score: F = 21.77, P < 0.001), but not between 3 months and 12 months follow‐up (P > 0.05 for all). Higher scores on anxiety and depression over time, older age, lower ejection fraction, and more co‐morbidity were associated with poorer health status scores on one or both of the KCCQ and SF‐12 subscales. The majority of the between‐patient variance of the mental component summary scores (82.6%), but not the KCCQ overall summary score (41.9%), KCCQ clinical summary score (36.2%) and physical component summary scores (23.2%), was explained by the sociodemographic, clinical and psychological factors.

Conclusion

The majority of LVAD patients show a significant improvement in health status after LVAD implantation. However, there are large differences in individual health status score trajectories which are only partly explained by measures of disease severity pre‐LVAD, co‐morbidity and psychological stress.
First Report for Electrochemical Determination of Levodopa and Cabergoline: Application for Determination of Levodopa and Cabergoline in Human Serum, Urine and Pharmaceutical Formulations
Authors: Tajik Somayeh , Taher Mohammad Ali , Beitollahi Hadi
Published: March 2014

The electrochemical oxidation of levodopa on the surface of a carbon paste electrode modified with graphene nanosheets, 1‐(4‐bromobenzyl)‐4‐ferrocenyl‐1H‐[1,2,3]‐triazole (1,4‐BBFT) and hydrophilic ionic liquid (n‐hexyl‐3‐methylimidazolium hexafluoro phosphate) as a binder is studied. It has been found that the oxidation of levodopa at the surface of a modified electrode occurs at a potential of about 210 mV less positive than that of an unmodified carbon paste electrode (CPE). The prepared modified electrode exhibits a very good resolution of the voltammetric peaks of levodopa and cabergoline. The electrode has been applied successfully for the determination of levodopa and cabergoline in some real samples.
Affinity capillary electrophoresis for the determination of binding affinities for low molecular weight heparins and antithrombin‐III
Authors: Dinges Meredith M. , Solakyildirim Kemal , Larive Cynthia K.
Published: March 2014

The anticoagulant properties of heparin stem in part from high‐affinity binding to antithrombin‐III (AT‐III) inducing a 300‐fold increase in its inhibitory activity against the coagulation protease factor Xa. The minimal structural requirements for AT‐III binding are contained in the rare heparin pentasaccharide sequence containing a 3,6‐O‐sulfated N‐sulfoglucosamine residue. ACE is used in this work to measure the relative AT‐III binding affinities of the low molecular weight heparins (LWMHs) dalteparin, enoxaparin, and tinzaparin and the synthetic pentasaccharide drug fondaparinux (Arixtra). Determination of the AT‐III binding affinities of the LWMHs is complicated by their inherent structural heterogeneity and polydispersity. The fractional composition of 3‐O‐sulfo‐N‐sulfoglucosamine residues was determined for each drug substance using 2D NMR and used in the interpretation of the ACE results.
Monacolin K production by citrinin‐free Monascus pilosusMS‐1 and fermentation process monitoring
Authors: Feng Yanli , Shao Yanchun , Zhou Youxiang , Chen Fusheng
Published: March 2014

Monacolin K (MK) is a naturally occurring hypocholesterolemic agent that specifically inhibits HMG‐CoA reductase. As a natural source of MK, Monascus‐fermented products are of special interest; however, some Monascus strains could produce citrinin, which is a nephrotoxin, as a contaminant in Monascus‐derived products. A Monascus pilosus strain (MS‐1) that produces high amounts of MK, but no citrinin, was screened in previous investigations. Herein, liquid‐state fermentation parameters of the MS‐1 strain were optimized using statistical methods to maximize the MK yield with potato juice as a basic medium. The maximum MK yield (326.74 μg/mL) was predicted with 50 mL of medium in a 250‐mL conical flask containing 30 g/L sucrose, 38.75 g/L soybean flour, 0.00105 mol/L Mg2+ at pH 5.48, and 8% v/v seed inoculum precultured for 42 h at 30°C, incubated at 30°C for 3 days, followed by further incubation for 11 days at 24.7°C. The verified MK yield was 390.68 μg/mL and the MK yield increased to 565.64 μg/mL after 21 days of fermentation. No citrinin was detected in MS‐1‐fermented products. The results suggest that citrinin‐free MK can be obtained from natural medium through liquid‐state fermentation in an economical way. This method will be of practical value to the industrial production of MK.
Immobilization of Aspergillus nigerATCC 1015 on bionatural structures for lipase production
Authors: Osho Michael Bamitale , Popoola Tope , Kareem Sarafdeen Olateju
Published: March 2014

Lipase of Aspergillus niger ATCC 1015 was immobilized onto matrices of a structural fibrous network (SFN) of pawpaw (Carica papaya) wood and vegetable sponge (VS) of (Luffa aegyptiaca) by physical entrapment through solid‐state fermentation. SFN‐ and VS‐immobilized lipases were characterized in terms of their operational and storage stability. The immobilizates were cross‐linked with ethanolic formaldehyde (EF), formaldehyde (F) and glutaraldehyde (GA). Ninety percent enzymatic activity was retained with GA as a coupling agent after 11 consecutive uses of SFN‐immobilized lipase, and after five, six, and four reuse times with EF, F, and uncross‐linked lipase, respectively. They showed different enzymatic characteristics (incubation time and operational stability) from those of VS‐immobilized enzyme. A relative activity above 75% was still achieved for the sample stored at 4°C and 50% at 28°C until fourth week of storage for both SFN‐ and VS‐immobilized lipases. In relation to the free biomass of A. niger ATCC 1015 hyphal cells, the SFN‐immobilized biomass with peak lipase activity (24.5 Ug−1) at day three resulted in 45.3% decrease in lipase production, whereas VS‐immobilized biomass with peak activity of 45.3 Ug−1 at day four resulted in 21.4% increase. This study revealed the potential of GA cross‐linked SFN as an excellent immobilizing agent.
Effectiveness of Cognitive Remediation and Emotion Skills Training (CREST) for Anorexia Nervosa in Group Format: A Naturalistic Pilot Study
Authors: Tchanturia Kate , Doris Eli , Fleming Caroline
Published: March 2014

Objective

This study aims to evaluate a novel and brief skills‐based therapy for inpatients with anorexia nervosa, which addressed ‘cold’ and ‘hot’ cognitions in group format.

Method

Adult inpatients with anorexia nervosa participated in the cognitive remediation and emotion skills training groups. Participants who attended all group sessions completed patient satisfaction and self‐report questionnaires.

Results

Analysis of the data showed that social anhedonia (measured by the Revised Social Anhedonia Scale) decreased significantly between pre‐ and post‐interventions, with small effect size (d = 0.39). Motivation (perceived ‘importance to change’ and ‘ability to change’) was found to have increased with small effect sizes (d = 0.23 and d = 0.16), but these changes did not reach statistical significance. The cognitive remediation and emotion skills training group had positive feedback from both the patients and therapists delivering this structured intervention.

Conclusion

Improved strategies are needed both in supporting inpatients to tolerate the group therapy setting and in helping them to develop the skills necessary for participation. Further larger‐scale research in this area is needed to consolidate these findings. Copyright © 2014 John Wiley & Sons, Ltd and Eating Disorders Association.
Flame retardants and heat release: review of data on individual polymers
Authors: Hirschler Marcelo M.
Published: March 2014

This work is the second of two parts that considered the following issue: do flame retardants affect heat release of polymers? The reason for investigating the issue is because it is important to assess whether the addition of flame retardants positively decreases fire hazard. This part of the work considered the two following issues. (1) Analysis of the individual polymeric materials that need to be studied. (2) Analysis of the data found on heat release (particularly peak heat release rate), ignitability (if available), and other thermal properties (as available) of polymers in small‐scale test data in recent years. The effects are being presented in terms of the percentage of improvement. The work demonstrated that, almost without exception, when adequately compounded systems were developed, the peak heat release rate of the flame retarded system was lower than that of the non‐flame retarded system. The overall conclusion of the two‐part study was that flame retardants does indeed improve fire safety (when used appropriately) and that a key reason for the beneficial effect of flame retardants is that they decrease heat release. Copyright © 2014 John Wiley & Sons, Ltd.
Selective Solid‐phase Extraction of Bisphenol A Using a Novel Stir Bar Based on Molecularly Imprinted Monolithic Material
Authors: Liu Kun‐Feng , Feng Rui , Zhang Yu‐Ping , Chen Jun , Bai Lian‐Yang
Published: March 2014

In this paper, a novel monolithic stir bar based on molecularly imprinted polymer (MIP) was firstly developed by filling modified neodymium magnet (Nd2Fe14B) powders into a glass tube (60 × 4 mm), followed by the imprinted grafting with bisphenol A (BPA) as the template molecule by thermal polymerization. It has been successfully used for the stir bar sorptive extraction (SBSE) and its extraction performance illustrated that the MIP‐encapsulated stir bar had stronger affinity to the template molecule, compared with the stir bar based on the non‐imprinted molecularly polymer (NIP). Under the optimal extraction conditions, a simple method based on the coupling of MIP‐SBSE with high performance liquid chromatography (HPLC) was used for the selective determination of the model mixtures of BPA, 4‐phenylphenol (PP) and phenol (P) in bottled water. The recoveries of BPA, PP and P were in the range of 88.5‐96.1%, 78.2‐89.7%, 81.3‐89.5% at three spiked levels, respectively, demonstrating that higher extraction and the specific absorption occurred between the template molecule and the prepared MIP stir bar.
A Convenient Preparation of Bis(4‐methoxyphenyl)methanethiol and Its Application in the Synthesis of Biotin Thioacid
Authors: Chou Tzyy‐Chao , Hsu Yu‐Ling , Lo Lee‐Chiang
Published: March 2014

We have established a facile protocol for the preparation of bis(4‐methoxyphenyl)methanethiol (4). Thiol 4 was used to prepare biotin thioester 7 which was later subjected to acidolysis to afford biotin thioacid (1b) in high yield. Compound 1b represents a new biotinylating reagent worth exploring and its spectral data was reported for the first time.
Baseline and new‐onset morphologic ECG abnormalities in healthy volunteers in phase I studies receiving placebo: Changes over a 6‐week follow‐up period
Authors: Hingorani Pooja , Karnad Dilip R. , Natekar Mili , Kothari Snehal , Narula Dhiraj
Published: March 2014

Morphological ECG abnormalities occur in 5–12% healthy adults participating in early phase clinical trials. We retrospectively analyzed 16,472 12‐lead ECGs recorded at multiple time points in 420 volunteers (282 males, 138 females; aged 18–76 years) randomized to receive placebo from 19 Phase I studies to see if some baseline ECG abnormalities may disappear or new abnormalities may appear during the study. One hundred forty‐four (34.3%) subjects had abnormal baseline ECGs, of which 66 (44.8%) reverted to normal during follow‐up. Of 276 (65.7%) subjects with normal baseline ECGs, 118 (42.8%) developed ECG abnormalities over the next 6 weeks. Common baseline abnormalities included sinus bradycardia, R wave transition abnormalities, right axis deviation, non‐specific T wave changes and atrial premature complexes. On follow‐up ECGs, prolonged QT interval, first‐degree AV block, sinus bradycardia, short PR interval, and R wave transition abnormalities reverted to normal. Common new‐onset abnormalities in subjects with normal baseline ECGs included sinus bradycardia, prolonged QT interval, non‐specific T wave changes, R wave transition abnormalities, and sinus tachycardia. Thus, transient morphological ECG changes may occur in healthy volunteers possibly due to diurnal variation, effect of food, hormones, or autonomic changes. This should be considered when interpreting “treatment‐emergent” ECG changes in clinical trials.
Characterization of process‐related impurities including forced degradation products of alogliptin benzoate and the development of the corresponding reversed‐phase high‐performance liquid chromatography method
Authors: Zhou YuXia , Zhou WenTao , Sun LiLi , Zou QiaoGen , Wei Ping , OuYang PingKai
Published: March 2014

The characterization of process‐related impurities and forced degradants of alogliptin benzoate (Alb) in bulk drugs and a stability‐indicating HPLC method for the separation and quantification of all the impurities were investigated. Alb was found to be unstable under acid and alkali stress conditions and two major degradation products (Imp‐F and Imp‐G) were observed. The optimum separation was achieved on Kromasil C18 (250 × 4.6 mm, 5 μm) using 0.1% perchloric acid (pH adjusted to 3.0 with triethylamine) and acetonitrile as a mobile phase in gradient mode. The proposed method was found to be stability indicating, precise, linear (0.10–75.0 μg/mL), accurate, sensitive, and robust for the quantitation of Alb and its process‐related substances and degradation products. The structures of 11 impurities were characterized and confirmed by NMR spectroscopy, MS, and IR spectroscopy, and the most probable formation mechanisms of all impurities were proposed according to the synthesis route.
Sobolev‐Jawerth embedding of Triebel‐Lizorkin‐Morrey‐Lorentz spaces and fractional integral operator on Hardy type spaces
Authors: Ho Kwok‐Pun
Published: March 2014

A Sobolev type embedding for Triebel‐Lizorkin‐Morrey‐Lorentz spaces is established in this paper. As an application of this result, the boundedness of the fractional integral operator on some generalizations of Hardy spaces such as Hardy‐Morrey spaces and Hardy‐Lorentz spaces are obtained.
Computational Search for Possible Mechanisms of 4‐Thiazolidinones Anticancer Activity: The Power of Visualization
Authors: Devinyak Oleg , Havrylyuk Dmytro , Zimenkovsky Borys , Lesyk Roman
Published: March 2014

Public databases of NCI‐60 tumor cell line screen results and measurements of molecular targets in the NCI‐60 panel give the opportunity to assign possible anticancer mechanism to compounds with positive outcome from antitumor assay. Here, the novel protocol of NCI databases mining where inferences are based on the visualization is presented and utilized with the aim to identify putative biological routes of 4‐thiazolidinones anticancer effect. As a result, highly potent 4‐thiazolidinone‐pyrazoline‐isatin conjugates show the similarity of activity patterns with puromycin and CBU‐028 and their pattern is also highly correlated with fraction of methylated CpG sites in CD34, AF5q31 and SYK. Several compounds from this group show strong negative correlation with fraction of methylated CpG sites in HOXA5. Thiopyrano[2,3‐d][1,3]thiazol‐2‐ones bearing naphtoquinone fragment were found to possess the same activity pattern as fusarubin does. But none of the studied 4‐thiazolidinone derivatives has activity fingerprint similar to standard anticancer agents. The obtained results bring medicinal chemistry closer to the understanding of basic nature of 4‐thiazolidinones effect on cancer cells.
The Development of Novel Chemical Fragment‐Based Descriptors Using Frequent Common Subgraph Mining Approach and Their Application in QSAR Modeling
Authors: Khashan Raed , Zheng Weifan , Tropsha Alexander
Published: March 2014

We present a novel approach to generating fragment‐based molecular descriptors. The molecules are represented by labeled undirected chemical graph. Fast Frequent Subgraph Mining (FFSM) is used to find chemical‐fragments (subgraphs) that occur in at least a subset of all molecules in a dataset. The collection of frequent subgraphs (FSG) forms a dataset‐specific descriptors whose values for each molecule are defined by the number of times each frequent fragment occurs in this molecule. We have employed the FSG descriptors to develop variable selection k Nearest Neighbor (kNN) QSAR models of several datasets with binary target property including Maximum Recommended Therapeutic Dose (MRTD), Salmonella Mutagenicity (Ames Genotoxicity), and P‐Glycoprotein (PGP) data. Each dataset was divided into training, test, and validation sets to establish the statistical figures of merit reflecting the model validated predictive power. The classification accuracies of models for both training and test sets for all datasets exceeded 75 %, and the accuracy for the external validation sets exceeded 72 %. The model accuracies were comparable or better than those reported earlier in the literature for the same datasets. Furthermore, the use of fragment‐based descriptors affords mechanistic interpretation of validated QSAR models in terms of essential chemical fragments responsible for the compounds’ target property.
Long‐time behavior of a nonlinear viscoelastic beam equation with past history
Authors: Narciso Vando
Published: March 2014

This paper is concerned with the existence of a global attractor for the nonlinear viscoelastic beam equation with past history memory
urn:x-wiley:1704214:media:mma3109:mma3109-math-0001

where g(ut) is a damping like | ut | rut and f(u) is a source term like | u | αu − | u | βu, by considering 0 ≤ β < α and r > 0. Copyright © 2014 John Wiley & Sons, Ltd.
A method for testing accuracy of the calibration standards based on reciprocity conditions of the error network
Authors: Dahlberg Krista , Silvonen Kimmo , Kiuru Tero
Published: March 2014

A method to define the accuracy of the known data of the calibration standards, presented in this article, is based on the reciprocity conditions of the error parameters. It can be seen that any error in calibration standards' definition leads to increasing apparent nonreciprocity in the error terms of passive test fixtures. It is an easy method to check the accuracy of the known data of the standards without any extra measurements or calculations. The method is demonstrated by simulations and wideband two‐tier on‐wafer measurements. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1036–1040, 2014
An all‐optical OCDMA encoder with simultaneous signal regeneration based on fiber four‐wave mixing
Authors: Galdino Lidia , Abbade Marcelo L. F. , Bonani L. H. , Marconi Jorge D. , Fragnito Hugo L. , Moschim Edson
Published: March 2014

A new all‐optical optical code division multiple access encoder that simultaneously regenerates input signals is proposed and experimentally investigated. The device is based on a fiber four‐wave mixing and experimental results show that eye penalties may be decreased up to 5.1 dB. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1024–1028, 2014
Theoretical analysis of graphene nanoantennas with different shapes
Authors: da Costa Karlo Q. , Dmitriev Victor , Nascimento Clerisson M. , Silvano Gustavo L.
Published: March 2014

In this article, we present a numerical analysis of graphene nanoantennas with rectangular, elliptical, triangular, and circular geometries in terahertz band. We model the electromagnetic scattering of these planar structures by the method of moments with the surface impedance of graphene. We analyze the absorbing cross section and the resonances of nanoantennas for different, sizes, chemical potential, temperature, and incident angle. The obtained results can be useful to design efficient nanoantennas for terahertz wireless communications. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1019–1024, 2014
MIMO multiband antenna system combining resonant and nonresonant elements
Authors: Andújar Aurora , Anguera Jaume
Published: March 2014

Multi‐input and multi‐output (MIMO) technology will enable high‐data rates in wireless devices to allow speech and video calls to streaming media and web browsing all over a common platform. MIMO technology needs M antennas both in transmission and reception. Because the space in a wireless device is limited, including M antennas is a challenge. To face such challenge, a MIMO antenna system is proposed, which comprises a multiband monopole antenna (35 × 15 mm2) and two small nonresonant elements, each one operating in a particular frequency region: 824–960 and 1710–2170 MHz. The size of each of the nonresonant elements is only 5 × 5 × 5 mm3. The proposed MIMO system is analyzed in terms of bandwidth, efficiency, correlation, and multiplexing efficiency. MIMO capacity is measured in a reverberation chamber considering a free‐space Rayleigh scenario and also including the effect of a phantom‐head and hand. The results reveal that the proposed MIMO system provides capacity close to the ideal bound, whereas having a small size and able to operate at several 2G, 3G, and 4G (long‐term evolution) standards. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1076–1084, 2014
Ultrawideband‐embedded multiband planar monopole antenna
Authors: Jung Pil Hyun , Kwak Jeong Seok , Lee Ha Eun , Yang Woon Geun
Published: March 2014

In this letter, we present an ultrawideband (UWB)‐embedded multiband planar monopole antenna. The proposed antenna is composed of a chopped semicircular radiator appended with a meander and a folded branch microstrip line. Owing to inclusion of the semicircular radiator, the antenna can have the UWB characteristic. Also, the meander and the folded‐branch microstrip line guarantee low‐frequency bands, including global system for mobile communication, digital communication system, personal communications service (PCS), United States personal communications service (US‐PCS), wideband code division multiple access, bluetooth, and US‐worldwide interoperability for microwave access. A high‐frequency structure simulator was used to analyze the proposed antenna in the design process and to compare the simulation and experimental results. The bandwidth of the proposed antenna was measured for voltage standing wave ration less than 3. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1111–1115, 2014
Broadband T‐matching loop tag antenna design for on‐body UHF RFID applications
Authors: Chiu Chien‐Wen , Tsai Min‐Chuan , Wang Hwang‐Cheng , Wu Ter‐Feng
Published: March 2014

This article proposes a printed loop tag antenna placed near a human body for use on student radio frequency identification cards. The proposed tag antenna printed on a polyvinylchloride card is a one‐wavelength loop fed by a T‐matching transformer. An equivalent lumped‐circuit for the T‐matching transformer is presented to synthesize the T‐matching feeding structure. A four‐layer stratified elliptical cylinder with physical parameters is utilized as a human model for EM simulations. The simulated bandwidth of the T‐matching loop tag antenna is 91 MHz (866–957 MHz, 10%). The T‐matching structure allows the loop antenna to have wideband characteristics. Experiments revealed that the reading distance ranges from about 3.3 to −6 m when the tag was placed in different positions on the human chest in the open space environment. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1194–1200, 2014
A reconfigurable printed dipole antenna using RF PIN diodes
Authors: Abbasiniazare Seyyedpayam , Manoochehri Omid , Forooraghi Keyvan
Published: March 2014

A frequency switchable printed dipole antenna is proposed for multiband application. The electrical length of the dipole can be changed by controlling the pin diodes states so that the antenna can operate in three different frequency bands. The larger/smaller of the current path, the smaller/larger of the resonance frequency can be obtained. Three resonant frequencies from 200 to 1400 MHz are selected in this bandwidth and proper matching is achieved for all resonant frequencies. Also, a pair of capacitive stubs at the end of dipole have been used for achieving a resonant frequency lower than a standard dipole of comparable length. For optimizing the antenna structure, a parametric analysis has been performed by calculating the length and width of radiators with formulas. All simulated results have been confirmed with measured data. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1151–1155, 2014
A robust design of a numerically demanding compact rat‐race coupler
Authors: Kurgan Piotr , Bekasiewicz Adrian
Published: March 2014

A fast and accurate design procedure of a computationally expensive microwave circuit has been presented step‐by‐step and experimentally validated on the basis of a compact rat‐race coupler (RRC) comprising slow‐wave resonant structures. The final compact RRC solution has been obtained by means of a sequential optimization scheme exploiting the implicit space mapping algorithm. A well‐suited surrogate optimization starting point as well as a considerable limitation of the surrogate optimization variables contribute significantly to the numerical efficiency of the method proposed. The final design, offering 85% size reduction together with a satisfactory performance, has been obtained with only a handful of EM simulations. The experimental validation of the method has been successfully conducted. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1259–1263, 2014
Compact printed log‐periodic dipole antenna for water detection by using ground penetrating radar
Authors: Elsheakh Dalia M. , Abdallah Esmat A.
Published: March 2014

Compact printed fractal log‐periodic dipole antenna (FLPDA) is proposed for water detection using ground penetrating radar (GPR). First fractal structure is introduced in an antenna design and evolves the traditional Euclidean log‐periodic dipole array (LPDA). A fabricated proof‐of‐concept prototype of the proposed antenna is printed on a FR4 substrate with a relative permittivity of 4.7 on both substrate thickness 1.6 and 9.5 mm with occupied area of 85 × 110 and 60 × 70 cm2, respectively. The fabricated antenna has approximately 75% size reduction as compared to traditional LPDA. The −10dB impedance bandwidth extends from 45 MHz to more than 500 MHz. Both numerical and experimental results show that the FLPDA antenna has stable directional radiation patterns and apparently miniaturized effect, which are suitable for various ultrawideband applications. Main parameters and characteristics of the proposed antenna are discussed using both electromagnetic simulation and measurement. The effect of sandy soil, water layer, and the distance between sand and proposed antennas are also studied. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1225–1232, 2014
An equivalent circuit model for a microstrip line with an asymmetric spiral‐shaped defected ground structure
Authors: Woo Duk‐Jae , Lee Taek‐Kyung , Lee Jae‐Wook
Published: March 2014

For a microstrip line with an asymmetric spiral‐shaped defected ground structure (DGS), an equivalent circuit model is presented. From the lumped‐element circuit model describing the asymmetric properties in circuit elements as well as in their magnetic coupling to the host line, the two rejection frequencies are derived. The equivalent circuit model provides physical insight into the dual‐frequency operation of the asymmetric spiral‐shaped DGS. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1222–1224, 2014
A quasistatic analysis of a plate on consolidating layered soils by analytical layer‐element/finite element method coupling
Authors: Ai Zhi Yong , Cheng Yi Chong , Cao Guo Jun
Published: March 2014

In this paper, a coupling method between finite element and analytical layer‐elements is utilized to analyze the time‐dependent behavior of a plate of any shape and finite rigidity resting on layered saturated soils. Based on the integral transform techniques together with the aid of an order reduction method, an analytical layer‐element solution is derived from the governing equations for three‐dimensional Biot consolidation with respect to a Cartesian coordinate system and then extended to be the fundamental solution for the layered saturated soil under a point load. The Mindlin plate is modeled by eight‐noded isoparametric elements. The governing equations of the interaction between soil and plate in the Laplace‐Fourier transformed domain are deduced by referring to the coupling theory of FEM/BEM, and the final solution is obtained by applying numerical inversion. Numerical examples concerned with the time‐dependent response of a plate are performed to demonstrate the influence of soil and plate properties on the interaction process. Copyright © 2014 John Wiley & Sons, Ltd.
Piezo‐Scantische für höchste Präzision und Dynamik
Authors: Hamann Gernot , Reiff Ellen‐Christine
Published: March 2014

Größtmögliche Positioniergenauigkeit ist heute in vielen Anwendungsbereichen obligatorisch. Beispiele reichen von der Halbleiterfertigung über die Biotechnologie bis hin zur optischen Messtechnik und Mikroskopie. Piezobasierte Scantische sind aus solchen Anwendungsbereichen kaum mehr wegzudenken. Durch ihre hohe Genauigkeit und Dynamik erschließen sie oftmals neue Möglichkeiten und treiben die Technik voran.
Präzise 3D‐Messung im Vorübergehen
Authors: Holst Gerhard , Strackenbrock Bernhard
Published: March 2014

Das MuSe‐Forschungsprojekt der Bayerischen Forschungsstiftung verfolgt zwei verschiedene Ziele, die es in Zukunft ermöglichen sollen, auf einfache Art und Weise mit Hilfe stationärer und portabler Messsysteme präzise 3D‐Modelle zu erstellen, z. B. von historischen Gebäuden. Hierzu sollen die Messdaten stationärer Laserscanner mit den Messdaten eines portablen Kamerasystems verknüpft werden. Zudem ist im Rahmen des Projekts zum ersten Mal ein solches Kamera basierendes Messsystem mit ausreichender Dynamik realisiert und erprobt worden. Die verschiedenen 3D‐Modelle, welche mit den Messdaten erzeugt werden, können verschiedene Anforderungen erfüllen, zum einen stellen sie eine wichtige Grundlage für eine Restaurierung dar, wenn Schäden entstehen, und zum anderen ermöglichen sie neue Arten der Vermittlung historischen Kulturguts über das Internet, wie z. B. virtuelle Besuche.
Phototoxic dermatoses in pediatric BMT patients receiving voriconazole
Authors: Goyal Rakesh K. , Gehris Robin P. , Howrie Denise , Cogley Kayla M. , Windreich Randy M. , Venkataramanan Raman
Published: March 2014

We investigated the incidence of phototoxic skin reactions in pediatric BMT recipients treated with voriconazole. Nine out of 40 patients (22.5%), all Caucasian, developed skin lesions in sun‐exposed distributions. Dermatologic findings included sunburn‐like erythema, pseudo‐porphyria, linear papulovesicular lesions, severe erosive cheilitis, dermatoheliosis and lentigines. Patients were treated with sun avoidance, high‐potency sunscreens, and topical steroids with significant improvement in all cases. Prolonged voriconazole use requires close monitoring for chronic skin toxicities. Long‐term risks including the risk of skin cancer need to be investigated. Pediatr Blood Cancer 2014;61:1325–1328. © 2014 Wiley Periodicals, Inc.
Secondary acute monocytic leukemia positive for 11q23 rearrangement in Nijmegen breakage syndrome
Authors: Pastorczak Agata , Szczepanski Tomasz , Trelinska Joanna , Finalet Ferreiro Julio , Wlodarska Iwona , Mycko Katarzyna , Polucha Anna , Sedek Lukasz , Meyer Claus , Marschalek Rolf , Młynarski Wojciech
Published: March 2014

Nijmegen breakage syndrome (NBS) is an autosomal recessive chromosomal instability disorder characterized by a high incidence of pediatric hematologic malignancies. Majority of patients affected are of Slavic origin and share the same founder mutation of 657del5 within the NBN gene encoding protein involved in DNA double‐strand breaks (DSB) repair. We report a case of a pediatric patient with NBS, who developed t(9;11)/AF9‐MLL‐positive AML as a second malignancy after successful treatment of T‐NHL. The coexistence of NBN and MLL mutations suggests that the profound dysfunction of NBN may promote alterations of MLL that is mediated by error‐prone non‐homologous end joining pathway particularly in patients treated with DNA topoisomerase II inhibitors. Pediatr Blood Cancer 2014; 61:1469–1471. © 2014 Wiley Periodicals, Inc.