bluuebunny/crossref_metadata_2025_split huggingface dataset:
A weighted kernel possibilistic c‐means algorithm based on cloud computing for clustering big data
Authors: Zhang Qingchen , Chen Zhikui 
Published: September 2014

SUMMARYPossibilistic c‐means (PCM) cluster algorithm has emerged as an important tool for data preprocessing widely used in data mining and knowledge discovery. Owning to the huge amount of data, high computational complexity, and noise‐corrupted data, the PCM algorithms scaled for big data find it difficult to produce a good result in real time. The paper proposes a weighted kernel PCM (wkPCM) algorithm to cluster data objects in appropriate groups. The proposed algorithm introduces weights to define the relative importance of each object in the kernel clustering solution, which reduces the corruption caused by noisy data. In order to improve the real time of the proposed algorithm, cloud computing technology is used to optimize wkPCM to propose a distributed wkPCM algorithm based on MapReduce, which can provide significant computation speed. Experiment demonstrates that the proposed possibilistic clustering algorithms can cluster big data in appropriate groups in real time. Copyright © 2014 John Wiley & Sons, Ltd.
Value of thyroid specific peroxidase and Ki‐67 stains in preoperative cytology for thyroid follicular tumors
Authors: Maruta Junko , Hashimoto Hironobu , Yamashita Hiroto , Noguchi Hitoshi , Noguchi Shiro , Kobayashi Tadao K. , Tsuneoka Hidehiro , Takahashi Mutsuo 
Published: September 2014

BackgroundThe aim of this study was to elucidate immunocytochemically whether thyroid specific peroxidase (TPO) and Ki‐67 can complement fine‐needle aspiration (FNA) cytology as useful markers in order to distinguish between follicular adenoma (FA) and follicular carcinoma (FC).MethodsWe studied 40 FAs and 68 FCs obtained by surgical resection. FNA cytology smears were divided into two groups: Cytology‐A (Cy‐A) (94 cases) with typical benign cytology and Cytology‐B (Cy‐B) (14 cases) with atypical cytology. FCs were divided into two groups: FC‐I (42 cases) without any poorly differentiated structures and FC‐II (26 cases) with some poorly differentiated structures. Cytology smears and histology from FAs and FCs were studied immunocytochemically for thyroid specific peroxidase (TPO) and Ki‐67.ResultsTPO expression was negative in 12.5% FAs, 21.4% FC‐I, and 46.2% FC‐II. In 68 FC cases, Cy‐B were more frequently observed in TPO‐negative cases (38.1%) than in TPO‐positive cases (12.8%). The mean Ki‐67 LI was 0.46 in FAs, 0.53 in FC‐I, and 1.13 in FC‐II. The high Ki‐67 LI was correlated with Cy‐B. Moreover, higher Ki‐67 LI showed a close relationship with distant metastasis. In 94 Cy‐A cases, 54 cases were FCs. When 38 cases with negative TPO or Ki‐67 LI over 0.62 were extracted from them, as many as 28 cases were FCs, the rate of FCs were significantly higher than the rest.ConclusionTherefore, addition of TPO stain and Ki‐67 stain to routine Papanicolaou stain could improve the diagnostic reliability of FNA cytology for FC with high degree of malignancy. Diagn. Cytopathol. 2015;43:202–209. © 2014 Wiley Periodicals, Inc.
Hypoxia Imaging of Tumor and Spatiotemporal Analysis during Oxygen Inhalation
Authors: Yamada Ryo , Horinouchi Hirohisa , Tsukada Kosuke 
Published: September 2014

SUMMARYTumor hypoxia is considered a potential therapeutic problem because it reduces the effects of radiation therapy. Clinical experience has shown that long‐term tumor oxygenation cannot be achieved with oxygen inhalation, but the mechanisms behind this phenomenon remain unknown. In this study, we designed an optical system for evaluating spatiotemporal changes in tissue oxygen tension (pO2) by phosphorescence quenching. The system can measure continuous changes in pO2 at a fixed point and can also perform two‐dimensional mapping of pO2 in any part of the tumor tissue. We implanted tumor tissue in a dorsal skinfold chamber (DSC) of C57BL/6 mice and observed tumor growth. The mice received oxygen inhalation and pO2 was measured. Tumor pO2 increased after inhalation but the oxygen level was not maintained despite continuous inhalation of pure oxygen; the tumor returned to a hypoxic state. These results mimic the clinical experience of oxygen inhalation treatment in radiation therapy. Our system reproduces the repeat hypoxic phenomenon in a murine tumor model and can be used to determine the mechanisms of oxygen metabolism in tumors.
Determination of Whitening Filter Order for Estimation of Electromechanical Mode by Regression Model Representing Power System Damping Characteristics
Authors: SUGAWARA NAOYA , SAITOH HIROUMI , AKIYAMA YASUTO , SAKAMOTO KUNIO 
Published: September 2014

SUMMARYThis paper proposes a new method of estimating accurately the modal damping of a weakly damped electromechanical oscillation in power systems. The proposed method is based on a whitening filter (finite impulse response filter) to estimate the modal damping from the system response and a regression model to express the relation between the modal damping and system state variables, such as the active and reactive power outputs of generators. The feature of the method is that an optimal order of the whitening filter is determined so as to minimize the error of the linear regression model. A simulation study using the IEEJ EAST 10 machine model shows that the proposed method is effective for accurate estimation of weakly damped oscillation modes.
A Precise Photolithography Process Control Method Using Virtual Metrology
Authors: TSUDA HIDETAKA , SHIRAI HIDEHIRO , KAWAMURA EIICHI 
Published: September 2014

SUMMARYVirtual metrology, which enables both precise controllability and economic efficiency for semiconductor manufacturing processes, has recently attracted interest. The current virtual metrology model is mainly based on hypothesis‐verification methods that depend on engineers' skills and updating of the model in accordance with situation changes in tools and processes. We propose a precise photolithography process control method using virtual metrology. In our method, we extract the current virtual metrology model by data mining, thus making updation is unnecessary.
Age, prognostic impact of QRS prolongation and left bundle branch block, and utilization of cardiac resynchronization therapy: findings from 14 713 patients in the Swedish Heart Failure Registry
Authors: Lund Lars H. , Benson Lina , Ståhlberg Marcus , Braunschweig Frieder , Edner Magnus , Dahlström Ulf , Linde Cecilia 
Published: September 2014

AimsAge is not a contraindication to cardiac resynchronization therapy (CRT), but the prevalence and prognostic impact of QRS prolongation with intraventricular conduction delay (IVCD) and left bundle branch block (LBBB), as well as CRT utilization, may differ with age. We tested the hypotheses that in the elderly: (i) IVCD and LBBB are more prevalent, (ii) IVCD and LBBB are more harmful, and (iii) CRT is underutilized.Methods and resultsWe studied 14 713 patients with ejection fraction ≤39% in the Swedish Heart Failure Registry and divided into age groups ≤65 years, 66–80 years and >80 years. Among 13 782 patients without CRT, IVCD was present in the three age groups in 11% vs. 15% vs. 19% and LBBB was present in 20% vs. 27% vs. 28%, respectively, (P < 0.001). The multivariable hazard ratio (HR) for all‐cause mortality over a median (interquartile range) follow‐up of 29 (12–53) months for IVCD vs. narrow QRS was 1.31 (1.06–1.63, P = 0.013) in the ≤65 year group, 1.32 (1.17–1.47, P < 0.001) in the 66–80 year group, and 1.26 (1.21–1.41, p < 0.001) in the >80 year group. For LBBB vs. narrow QRS it was 1.29 (1.07–1.56, P = 0.009), 1.17 (1.06–1.30, P = 0.002), and 1.10 (0.99–1.22, P = 0.091), respectively. The adjusted P for interaction between age and QRS morphology was 0.664. In the three age groups, CRT was present in 6% vs. 8% vs. 4% and absent but with indication in 23% vs. 32% vs. 37%, respectively (P < 0.001).ConclusionsBoth IVCD and LBBB were more common with increasing age and were similarly strong independent predictors of mortality and in all ages. The underutilization of CRT was worse with increasing age.
Synthesis of Bulk Kesterite – A Prospective Photovoltaic Material
Authors: Podsiadlo Slawomir , Bialoglowski Maciej , Matyszczak Grzegorz , Marek Paulina , Gebicki Wojciech , Bacewicz Rajmund , Stachowicz Marcin , Dluzewski Piotr , Wozniak Krzysztof 
Published: September 2014

AbstractA rapid development of photovoltaics has been observed recently. Permanent interest in new cheap and efficient photovoltaic devices stimulates a constant search for new semiconductor materials and structures. The success of materials based on CIGS (CuIn1–xGaxSe2) is limited by the prohibitive prices of the elements In and Ga. A family of quaternary semiconducting materials of the Cu2ZnSnS4 type, crystallizing mainly in the kesterite structure, offers a promise of new cheap photovoltaic materials. Kesterite is manufactured from nontoxic and naturally abundant materials. The energy gap of Cu2ZnSnS4 is about 1.5 eV, and the absorption coefficient of this direct‐band‐gap material is α > 104 cm–1 for photon energies higher than the energy gap. In this paper, we report a method of obtaining free‐standing single crystals of kesterite (Cu2ZnSnS4).
Complex Formation between [(η6‐p‐cymene)Ru(H2O)3]2+ and Hydroxycarboxylates or their Sulfur Analogues – The Role of Thiolate Groups in Metal Ion Binding
Authors: Hüse Dániel , Bíró Linda , Patalenszki János , Bényei Attila Csaba , Buglyó Péter 
Published: September 2014

AbstractThe interactions between [(η6‐p‐cymene)Ru(H2O)3]2+ and L‐malic acid (H2mal), L‐tartaric acid (H2tart), and their sulfur‐containing analogues dl‐thiomalic acid (H3thiomal) and meso‐2,3‐dimercaptosuccinic acid (H4dmsa) were studied by pH potentiometry, NMR spectroscopy, and ESI‐MS. The hydroxycarboxylates are potent metal ion binders and prevent hydrolysis at pH 7.4 in aqueous solution. Although H2mal forms mononuclear complexes with different degrees of protonation by the involvement of the alcohol/alkoxide group in addition to the carboxylate groups, the presence of binding isomers is detected for the H2tart system. The replacement of the alcohol group by a thiolate group results in the formation of dinuclear [Ru2A2] complexes as the single species over a wide pH range. Complexes with identical binding modes with H3thiomal or polymeric species with H4dmsa are identified, and the X‐ray structure of [{(η6‐p‐cym)Ru}2(Hthiomal)2] is reported. The stereochemistry of the chiral‐at‐metal complexes was explored by NMR spectroscopy and is also discussed.
Synthesis and Properties of a Bis[(nitronyl nitroxide)‐2‐ide radical anion]–Palladium Complex
Authors: Suzuki Shuichi , Yokoi Hiroyuki , Kozaki Masatoshi , Kanzaki Yuki , Shiomi Daisuke , Sato Kazunobu , Takui Takeji , Okada Keiji 
Published: September 2014

AbstractThe chemical reduction of a bis[(nitrosonium nitroxide)‐2‐ide]palladium dication, NN+‐Pd‐NN+, selectively produced reduced complexes: a stable radical cationic species, NN‐Pd‐NN+, composed of a nitronyl nitroxide (NN) and a nitrosonium nitroxide (NN+), and a stable diradical species, NN‐Pd‐NN. NN‐Pd‐NN+ showed spin‐localization in one of the nitronyl nitroxide groups, i.e., slow exchange between NN and NN+, whereas NN‐Pd‐NN exhibited a moderately large negative exchange interaction of J/kB = –36 K with a singlet ground state.
Effect of the Metal Ion on the anti T. cruzi Activity and Mechanism of Action of 5‐Nitrofuryl‐Containing Thiosemicarbazone Metal Complexes
Authors: Cipriani Micaella , Toloza Jeannette , Bradford Lara , Putzu Eugenia , Vieites Marisol , Curbelo Estela , Tomaz Ana Isabel , Garat Beatriz , Guerrero Juan , Gancheff Jorge S. , Maya Juan Diego , Olea Azar Claudio , Gambino Dinorah , Otero Lucía 
Published: September 2014

AbstractChagas disease, caused by the protozoan parasite Trypanosoma cruzi, is a major health problem worldwide. In this work, we report the development of palladium and platinum metal complexes with 5‐nitrofuryl‐containing thiosemicarbazones (L) as bioactive ligands against T. cruzi and PTA (1,3,5‐triaza‐7‐phosphaadamantane) as co‐ligand. Eight new complexes of the formula [MCl(L)(PTA)] with M = Pd or Pt were synthesized and fully characterized. Most complexes showed similar activities against T. cruzi to those of the corresponding free thiosemicarbazone ligands. No significant differences between palladium and platinum complexes were observed. Metal compounds with the phenylthiosemicarbazone derivative were the most active ones (IC50 = 9.84 ± 0.32 and 4.94 ± 0.24 μM for Pd2+ and Pt2+, respectively). The prepared complexes were not toxic on mammalian cells, showing selective indexes of more than 10–20. The ability of the complexes to be reduced in the parasite, which leads to toxic free radical species, was confirmed by the detection of OH· and nitroanion free radical species by ESR spectroscopy experiments. Gel electrophoresis and fluorescence experiments were consistent with an intercalating‐like mode of DNA interaction for the complexes, but DNA interaction does not seem to be the main mechanism of anti T. cruzi action for these compounds. The results obtained show that complexation of the bioactive ligands with the selected metals is a valid strategy to obtain improved metal‐based antiparasitic compounds.
Activation of a 1‐Chlorophosphirane Complex by Aluminum Trichloride: Generation and Trapping of [Fc‐P‐W(CO)5] (Fc = Ferrocenyl)
Authors: Ho Feny , Ganguly Rakesh , Mathey François 
Published: September 2014

AbstractAluminum trichloride catalyzes the ring opening of a 1‐chlorophosphirane W(CO)5 complex and its reaction with thiophene and ferrocene to give the corresponding 1‐(2‐thienyl)‐ and 1‐ferrocenylphosphirane derivatives. The W(CO)5 complex of the 1‐ferrocenylphosphirane is an efficient precursor of the phosphinidene complex [FcP‐W(CO)5], which is trapped by tolan, trans‐stilbene, and water.
Metallacrown Ether Catalysts Containing Phosphine–Phosphite Polyether Ligands for Rh‐Catalyzed Asymmetric Hydrogenation – Enhancements in Activity and Enantioselectivity
Authors: Song Feng‐Tao , Ouyang Guang‐Hui , Li Yong , He Yan‐Mei , Fan Qing‐Hua 
Published: September 2014

AbstractA new class of tunable metallacrown ether rhodium catalysts based on α,ω‐(phosphine–phosphite) polyether ligands were prepared either by a template‐induced method or by a nontemplate procedure. For the asymmetric hydrogenation of α‐arylenamides with the addition of K+ cations, the ortho‐diphenylphosphine‐substituted metallacrown ether catalyst showed high enantioselectivities (up to 99 % ee), which are comparable to or better than the results obtained for phosphine–phosphite ligands with two or more chiral elements. Remarkable enhancements in enantioselectivity and noticeably increased catalytic activity were achieved through the supramolecular recognition between K+ cations and the metallacrown ether catalyst.
Specific 1,2‐Hydride Shift in the Boron Trifluoride Catalyzed Reactions of Aromatic Aldehydes with Diazoacetonitrile: Simple Synthesis of β‐Ketonitriles
Authors: Yang Zhanhui , Son Kwon‐Il , Li Siqi , Zhou Bingnan , Xu Jiaxi 
Published: September 2014

AbstractA series of β‐ketonitriles was synthesized within 30 min under mild conditions through the BF3·OEt2‐catalyzed addition reactions of diazoacetonitrile to aromatic aldehydes and subsequent 1,2‐hydride shift. This method is advantageous in that it is operationally simple, mild and metal‐free conditions are used, the substrate scope is wide, and the products are obtained in moderate to high yields (up to 81 %). Additionally, γ,δ‐unsaturated β‐ketonitriles are also accessible by this method by using cinnamaldehydes.
Effect-directed analysis of Elizabeth River porewater: Developmental toxicity in zebrafish (Danio rerio)
Authors: Fang Mingliang , Getzinger Gordon J. , Cooper Ellen M. , Clark Bryan W. , Garner Lindsey V.T. , Di Giulio Richard T. , Ferguson P. Lee , Stapleton Heather M. 
Published: September 2014

Abstract

In the present study, effect-directed analysis was used to identify teratogenic compounds in porewater collected from a Superfund site along the Elizabeth River estuary (VA, USA). Zebrafish (Danio rerio) exposed to the porewater displayed acute developmental toxicity and cardiac teratogenesis, presumably because of elevated sediment levels of polycyclic aromatic hydrocarbons (PAHs) from historical creosote use. Pretreatment of porewater with several physical and chemical particle removal methods revealed that colloid-bound chemicals constituted the bulk of the observed toxicity. Size-exclusive chromatography and normal-phase high-performance liquid chromatography were used to fractionate Elizabeth River porewater. Acute toxicity of porewater extracts and extract fractions was assessed as the pericardial area in embryonic zebrafish. The most toxic fraction contained several known aryl hydrocarbon receptor (AhR) agonists (e.g., 1,2-benzofluorene and 1,2-benzanthracene) and cytochrome P450 A1 (CPY1A) inhibitors (e.g., dibenzothiophene and fluoranthene). The second most toxic fraction contained known AhR agonists (e.g., benzo[a]pyrene and indeno[1,2,3-cd]pyrene). Addition of a CYP1A inhibitor, fluoranthene, increased toxicity in all active porewater fractions, suggesting synergism between several contaminants present in porewaters. The results indicate that the observed acute toxicity associated with Elizabeth River porewater results from high concentrations of AhR agonistic PAHs and mixture effects related to interactions between compounds co-occurring at the Elizabeth River site. However, even after extensive fractionation and chemical characterization, it remains plausible that some active compounds in Elizabeth River porewater remain unidentified. Environ Toxicol Chem 2014;33:2767–2774. © 2014 SETAC
Fabrication of cancellous biomimetic chitosan‐based nanocomposite scaffolds applying a combinational method for bone tissue engineering
Authors: Jamalpoor Zahra , Mirzadeh Hamid , Joghataei Mohammad Taghi , Zeini Darya , Bagheri‐Khoulenjani Shadab , Nourani Mohammad Reza 
Published: September 2014

AbstractThe aim of this study was to mimic the specific structure of bone and fabricate a biomimetic nano‐hydroxyapatite (HA)/chitosan (Cs)/gelatin scaffolds using combination of particle leaching and freeze drying methods eliminating mold effects. To achieve an optimum structure, scaffolds with different gelatin/Cs weight ratio were fabricated. Morphological characterization of scaffolds by scanning electron microscopy method showed highly interconnected porous structures similar to cancellous bone with mean pore size ranging from 140 to 190 μm. Nano‐HA crystals were dispersed homogeneously in the polymer matrix according to the energy‐dispersive X‐ray spectroscopy and transmission electron microscopy images. Fourier transform infrared and X‐ray diffraction results disclosed that chemical interactions were formed between nano‐HA, Cs, gelatin and crystallinity of each material decreased with blending. It was found that increasing the gelatin content significantly improved water uptake, degradation rate as well as attachment, infiltration and proliferation of Saos2 cells to the scaffolds. The presented results confirm that the designed biomimetic nano‐HA /Cs/gelatin scaffolds can be used as promising substitutes for bone tissue engineering. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 1882–1892, 2015.
PTH Receptor Signaling in Osteoblasts Regulates Endochondral Vascularization in Maintenance of Postnatal Growth Plate
Authors: Qiu Tao , Xian Lingling , Crane Janet , Wen Chunyi , Hilton Matthew , Lu William , Newman Peter , Cao Xu 
Published: September 2014

ABSTRACT

Longitudinal growth of postnatal bone requires precise control of growth plate cartilage chondrocytes and subsequent osteogenesis and bone formation. Little is known about the role of angiogenesis and bone remodeling in maintenance of cartilaginous growth plate. Parathyroid hormone (PTH) stimulates bone remodeling by activating PTH receptor (PTH1R). Mice with conditional deletion of PTH1R in osteoblasts showed disrupted trabecular bone formation. The mice also exhibited postnatal growth retardation with profound defects in growth plate cartilage, ascribable predominantly to a decrease in number of hypertrophic chondrocytes, resulting in premature fusion of the growth plate and shortened long bones. Further characterization of hypertrophic zone and primary spongiosa revealed that endochondral angiogenesis and vascular invasion of the cartilage were impaired, which was associated with aberrant chondrocyte maturation and cartilage development. These studies reveal that PTH1R signaling in osteoblasts regulates cartilaginous growth plate for postnatal growth of bone. © 2014 American Society for Bone and Mineral Research.
A vectorized multiscale compressed decomposition‐based solver for partial element equivalent circuit method
Authors: Antonini Giulio , Romano Daniele 
Published: September 2014

SummaryThe high level of integration has made the analysis and design of integrated circuits and packages increasingly challenging. Hence, there exists an urgent need to reduce the computational complexity of existing numerical methods. The integral equation‐based method known as the partial element equivalent circuit (PEEC) method naturally generates an equivalent circuit that can be analyzed in both the time and frequency domains. The enforcement of Kirchhoff laws to the equivalent circuit may easily result into a very large set of equations whose solution can be extremely time‐consuming.In this paper, we propose a vectorized version, over the frequency sweep, of the adaptive cross approximation algorithm. Furthermore, the multiscale block decomposition is applied to the PEEC method, powered by a vectorization strategy and an efficient management of the random access memory. It is found that the proposed use of vectorization and compression techniques in the framework of the multiscale block decomposition results in a significant computational speedup of the frequency‐domain analysis of PEEC models. The efficiency and accuracy of the proposed method are demonstrated through its application to two pertinent problems. Copyright © 2014 John Wiley & Sons, Ltd.
Different but Similar: Social Comparison of Travel Motives Among Tourists
Authors: Doran Rouven , Larsen Svein , Wolff Katharina 
Published: September 2014

AbstractAlthough previous research suggests that people prefer to think of themselves as being authentic (or individualistic) travellers rather than stereotyped tourists, there have been few studies investigating the external validity of such claim. This paper addresses this research gap by investigating tendencies to dissociate the self from typical tourists in terms of travel motivation. Findings suggest that people perceive their own travel motives to be different from those who they perceive as typical tourists and that these tendencies generalize across people involved in different forms of tourism. This paper discusses the results from a social psychological perspective and provides implications for future research and destination management alike. © 2014 The Authors. International Journal of Tourism Research published by John Wiley & Sons, Ltd.