bluuebunny/crossref_metadata_2025 huggingface dataset:
Rheological properties and foam preparation of biodegradable poly(butylene succinate)
Authors: Li Guan , Qi Rongrong , Lu Jiaqi , Hu Xinli , Luo Yu , Jiang Pingkai
Published: May 2012

To produce biodegradable poly(butylene succinate) (PBS) foam by compression molding, high viscosity PBS was prepared with dicumyl peroxide (DCP) as a crosslinking agent and trimethylolpropane trimethacrylate (TMPTMA) as a curing coagent by crosslink method. The influences of various factors on the foaming process and the properties of PBS foams were investigated. The results show that the use of DCP and TMPTMA simultaneously can effectively increase the melt viscosity of PBS. Zinc oxide/zinc stearate was used to reduce the thermal decomposition temperature of the blowing agent azodicarbonamide, which can balance well the vulcanization of PBS and the decomposition of blowing agent. Finally, closed‐cell PBS foams with degradable property have been successfully prepared by a traditional chemical compression molding foaming way. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The strange case of eugenics: A subject's ontogeny in a long‐lived classification scheme and the question of collocative integrity
Authors: Tennis Joseph T.
Published: May 2012

This article introduces the problem of collocative integrity present in long‐lived classification schemes that undergo several changes. A case study of the subject “eugenics” in the Dewey Decimal Classification is presented to illustrate this phenomenon. Eugenics is strange because of the kinds of changes it undergoes. The article closes with a discussion of subject ontogeny as the name for this phenomenon and describes implications for information searching and browsing.
Influence of Solvent and Bridge Structure in Alkylthio‐Substituted Triphenylamine Dyes on the Photovoltaic Properties of Dye‐Sensitized Solar Cells
Authors: Sakong Chun , Kim Se Hun , Yuk Sim Bum , Namgoong Jin Woong , Park Se Woong , Ko Min Jae , Kim Dong Hoe , Hong Kug Sun , Kim Jae Pil
Published: May 2012

Three new triphenylamine dyes that contain alkylthio‐substituted thiophenes with a low bandgap as a π‐conjugated bridge unit were designed and synthesized for organic dye‐sensitized solar cells (DSSCs). The effects of the structural differences in terms of the position, number, and shape of the alkylthio substituents in the thiophene bridge on the photophysical properties of the dye and the photovoltaic performance of the DSSC were investigated. The introduction of an alkylthio substituent at the 3‐position of thiophene led to a decrease in the degree of redshift and the value of the molar extinction coefficient of the charge‐transfer band, and the substituent with a bridged structure led to a larger redshift than that of the open‐chain structure. The introduction of bulky and hydrophobic side chains decreased the short‐circuit photocurrent (Jsc), which was caused by the reduced amount of dye adsorbed on TiO2. This resulted in a decrease in the overall conversion efficiency (η), even though it could improve the open‐circuit voltage (Voc) due to the retardation of charge recombination. Furthermore, the change in solvents for TiO2 sensitization had a critical effect on the performance of the resulting DSSCs due to the different amounts of dye adsorbed. Based on the optimized dye bath and molecular structure, the ethylene dithio‐substituted dye (ATT3) showed a prominent solar‐to‐electricity conversion efficiency of 5.20 %.
The empirical coverage of confidence intervals: Point estimates and confidence intervals for confidence levels
Authors: Schall Robert
Published: May 2012

Many confidence intervals calculated in practice are potentially not exact, either because the requirements for the interval estimator to be exact are known to be violated, or because the (exact) distribution of the data is unknown. If a confidence interval is approximate, the crucial question is how well its true coverage probability approximates its intended coverage probability. In this paper we propose to use the bootstrap to calculate an empirical estimate for the (true) coverage probability of a confidence interval. In the first instance, the empirical coverage can be used to assess whether a given type of confidence interval is adequate for the data at hand. More generally, when planning the statistical analysis of future trials based on existing data pools, the empirical coverage can be used to study the coverage properties of confidence intervals as a function of type of data, sample size, and analysis scale, and thus inform the statistical analysis plan for the future trial. In this sense, the paper proposes an alternative to the problematic pretest of the data for normality, followed by selection of the analysis method based on the results of the pretest. We apply the methodology to a data pool of bioequivalence studies, and in the selection of covariance patterns for repeated measures data.
Influence measures based on the volume of confidence ellipsoids for GEE
Authors: Pardo María Carmen , Alonso Rosa
Published: May 2012

The generalized estimating equations (GEE) derived by Liang and Zeger to analyze longitudinal data have been used in a wide range of medical and biological applications. To make regression a useful and meaningful statistical tool, emphasis should be placed not only on inference or fitting, but also on diagnosing potential data problems. Most of the usual diagnostics for linear regression models have been generalized for GEE. However, global influence measures based on the volume of confidence ellipsoids are not available for GEE analysis. This article presents an extension of these measures that is valid for correlated‐measures regression analysis using GEEs. The proposed measures are illustrated by an analysis of epileptic seizure count data arising from a study of prograbide as an adjuvant therapy for partial seizures and some simulated data sets.
Studying host cell protein interactions with monoclonal antibodies using high throughput protein A chromatography
Authors: Sisodiya Vikram N. , Lequieu Joshua , Rodriguez Maricel , McDonald Paul , Lazzareschi Kathlyn P.
Published: May 2012

Protein A chromatography is typically used as the initial capture step in the purification of monoclonal antibodies produced in Chinese hamster ovary (CHO) cells. Although exploiting an affinity interaction for purification, the level of host cell proteins in the protein A eluent varies significantly with different feedstocks. Using a batch binding chromatography method, we performed a controlled study to assess host cell protein clearance across both MabSelect Sure and Prosep vA resins. We individually spiked 21 purified antibodies into null cell culture fluid generated with a non‐producing cell line, creating mock cell culture fluids for each antibody with an identical composition of host cell proteins and antibody concentration. We demonstrated that antibody‐host cell protein interactions are primarily responsible for the variable levels of host cell proteins in the protein A eluent for both resins when antibody is present. Using the additives guanidine HCl and sodium chloride, we demonstrated that antibody‐host cell protein interactions may be disrupted, reducing the level of host cell proteins present after purification on both resins. The reduction in the level of host cell proteins differed between antibodies suggesting that the interaction likely varies between individual antibodies but encompasses both an electrostatic and hydrophobic component.
Three‐dimensional visualization of the cutaneous angiosome using angiography
Authors: Yin Zhi‐Xun , Peng Tian‐Hong , Ding Hong‐Mei , Bai Bo , Tang Mao‐Lin
Published: May 2012

The purpose of this study was to establish the three‐dimensional (3D) architecture of the cutaneous angiosome for assessment and design of the perforator flaps. Two fresh cadavers were injected with carboxymethyl cellulose (CMC)/lead oxide and computed tomography (CT) scanned before and after the injection. The various parts of the cutaneous and subcutaneous tissue derived from one of the injected cadavers were also CT scanned. Three‐dimensional reconstruction of the cutaneous angiosome and the two flap designs were performed using Materialise's Interactive Medical Image Control System (MIMICS). Both the reconstructed cutaneous angiosomes and the digital flaps can be displayed independently or in conjunction with bones, source arteries, and skin. The 3D architecture of the cutaneous angiosome ensures clear display of the spatial location, distribution range, and anastomoses relationship of the cutaneous perforators. In addition, the caliber, length, and position of a particular source artery are illustrated in the exact spatial location. As a result, the technique provides visualization of the general area and the expandable direction of a respective flap. This technique has the potential to play an important role in assessing perforator blood supply territory and in the design of new flaps.Clin. Anat. 2013. © 2012 Wiley Periodicals, Inc.
The lateral thoracic artery passing through duplicated axillary vein: A case report
Authors: Kyung Dong‐Soo , Lee Jae‐Ho , Kim Dae‐Kwang , Choi In‐Jang
Published: May 2012

The axillary vein is a large‐blood vessel that lies on the medial side to the axillary artery. The veins of the axilla are more abundant than the arteries and their variations were extremely common. During educational dissection, a rare form of the axillary vein accompanying arterial variation was founded in left arm of 70‐year‐old female cadaver. The axillary vein was divided into two large veins, anterior and posterior axillary veins according to their anatomical position. The lateral‐thoracic artery arose from the second part of the axillary artery and passed through the gap of duplicated axillary vein. Before the lateral‐thoracic artery passed through the gap of duplicated axillary vein, the lateral‐thoracic artery gave‐off an additional branch, which descended superficial to the anterior axillary vein. It surrounded the anterior axillary vein as annular form and the diameter of surrounded part of the anterior axillary vein became narrow. This novel case was reported and its clinical implications of such a variant were discussed. Clin. Anat. 26:1014–1016, 2013. © 2012 Wiley Periodicals, Inc.
Novel findings of the anatomy and variations of the axillary vein and its tributaries
Authors: Yang Hee‐Jun , Gil Young‐Chun , Jin Jeong‐Doo , Cho Hyejin , Kim Hyun , Lee Hye‐Yeon
Published: May 2012

The anatomy and variations of the axillary vein has significant implications in various invasive procedures such as venous access, axillary block, arteriovenous fistula creation, axillary node dissection, breast augmentation, and other surgical procedures involving the axilla. To clarify the anatomy of the axillary vein and its tributaries, 40 cadaveric upper extremities were examined after dissection and were classified into several types according to the courses and terminations of brachial veins. The brachial veins ended separately (Type A; 72.5%) or made a common brachial vein (Type B; 27.5%) to enter the basilic vein or the axillary vein. The basilic vein was absent in 5.0% of the specimens. Duplication of the axillary vein was observed in 17.5% of the specimens and the lateral venous channel running along the lateral wall of the axilla was observed in 40.0% of the specimens. The most common drainage vein of the deep brachial vein was the lateral brachial vein (67.5%). The anterior circumflex humeral vein also emptied into the lateral brachial vein in 67.5% of the specimens. The posterior circumflex humeral vein crossed posterior side of the brachial plexus to join either the axillary vein (45.0%) or subscapular vein (42.5%). Perforation of the lateral root of median nerve by a lateral brachial vein, a common brachial vein, or a venous channel was observed in 15.0% of the specimens. Other venous variations accompanying the variations of the axillary artery or the brachial artery are described herein. The clinical importance of these findings is described in the discussion. Clin. Anat. 25:893–902, 2012. © 2012 Wiley Periodicals, Inc.
Clarification of the identity of the mammalian fifth pharyngeal arch artery
Authors: Bamforth Simon D. , Chaudhry Bill , Bennett Michael , Wilson Robert , Mohun Timothy J. , Van Mierop Lodewyk H.S. , Henderson Deborah J. , Anderson Robert H.
Published: May 2012

The remodeling of the pharyngeal arch arteries is a complex process that occurs across vertebrates, although the specific number of arteries varies across species, with six in fish, but only five in birds and mammals, although they are numbered one through four, and six. The existence of a fifth arch artery in mammals has been debated for more than a century. Although some have doubted, and continue to doubt, its existence, several cardiovascular malformations can be explained only on the basis of its presence. We have analyzed the developing pharyngeal arch arteries in mouse and human embryos, using high‐resolution episcopic microscopy. We have then created three‐dimensional models, allowing us to identify any structures that would satisfy the descriptions of fifth arch arteries. This detailed examination revealed collateral channels connecting the fourth and sixth pharyngeal arch arteries in approximately half of the mouse embryos examined. Such collateral channels were seen in only one human embryo of eight examined by high‐resolution episcopic microscopy, although we had previously identified such collateral channels using wax plate reconstruction. An extra vessel, occupying a discrete component of the pharyngeal mesenchyme, and therefore resembling a true fifth pharyngeal arch artery, was observed in one Carnegie Stage 14 human embryo. The pharyngeal mesenchyme in the human, therefore, can contain a fifth arch, with a contained artery, albeit transiently. Persistence of this structure, and the observed collateral channels, provides mechanisms to explain the congenital cardiovascular malformations described as persistent fifth aortic arch, and double‐barreled aorta. Clin. Anat. 2013. © 2012 Wiley Periodicals, Inc.
Implementing and evaluating scheduling policies in gLite middleware
Authors: Kretsis A. , Kokkinos P. , Varvarigos E. A.
Published: May 2012

Grid scheduling algorithms are usually implemented in a simulation environment using tools that hide the complexity of the Grid and assumptions that are not always realistic. In our work, we describe the steps followed, the difficulties encountered and the solutions provided to develop and evaluate a scheduling policy, initially implemented in a simulation environment, in the gLite Grid middleware. Our focus is on a scheduling algorithm that allocates in a fair way the available resources among the requested users or jobs. During the actual implementation of this algorithm in gLite, we observed that the validity of the information used by the scheduler for its decisions affects greatly its performance. To improve the accuracy of this information, we developed an internal feedback mechanism that operates along with the scheduling algorithm. Also, a Grid computation resource cannot be shared concurrently between different users or jobs, making it difficult to provide actual fairness. For this reason we investigated the use of virtualization technology in the gLite middleware. We did a proof‐of‐concept implementation and performed an experimental evaluation of our scheduling algorithm in a small gLite testbed that proves the validity and applicability of our solutions. Copyright © 2012 John Wiley & Sons, Ltd.
Effective electro‐optic coefficient of (1–x)Pb(Zn1/3Nb2/3)O3–xPbTiO3 single crystals
Authors: He Chongjun , Chen Hongbing , Sun Liang , Wang Jiming , Xu Feng , Du Chaoling , Zhu Kongjun , Liu Youwen
Published: May 2012

Refractive indices and effective electro‐optic coefficient γc of (1–x)Pb(Zn1/3Nb2/3)O3–xPbTiO3 (PZN‐xPT, x = 0.05, 0.09 and 0.12) single crystals were measured at 532 nm wavelength. Orientation and temperature dependences of the electro‐optic coefficient were investigated. Large electro‐optic coefficient (γc = 470 pm/V) was observed in [001]‐poled PZN‐0.09PT crystal. More importantly, γc of tetragonal PZN‐0.12PT is almost unchanged in a temperature range −20 ∼ 80 °C. The γc of PZN‐xPT single crystals are much higher than that of widely used electro‐optic crystal LiNbO3 (γc = 20 pm/V). These results show that PZN‐xPT single crystals are very promising materials for electro‐optic modulators in optical communications.
Non‐financial Information About Sustainable Development and Environmental Policy in the Annual Reports of Listed Companies: Evidence from Italy and the UK
Authors: Mio Chiara , Venturelli Andrea
Published: May 2012

The truthful and correct representation of a company's current performance and its future prospects needs to account for a variety of sustainability issues, given that they are exerting an ever greater impact on strategic and operational decisions, risk profiles and balance sheet item valuations.

Nowadays, companies operate in a context in which such issues as sustainable development, environmental policy, and stakeholder engagement are of increasing strategic importance.

While such issues are also addressed in regulatory provisions, they require further study to meet the challenge of representing social and environmental factors, as, in the context of annual report disclosures, it is not possible to proceed simply by analogy.

The present study compares sustainability disclosures from the annual reports of the top 50 listed firms (by number of employees) in two countries – Italy and the United Kingdom – which have different legal systems. The objective is to analyze whether different territorial contexts might affect, under different headings, the qualitative aspects of the non‐financial disclosures contained in the annual reports of the firms under examination. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment
Extended IEEE 802.15.4 using CSMA/CA with Timing Group Division for high performance
Authors: Kobayashi Hideyuki , Sugiura Akihiko
Published: May 2012

We propose Timing Group Division (TGD) for faster IEEE 802.15.4 throughput. Our proposed method splits terminals into groups. All terminals in each group have both TGD delay and CSMA/CA delay. Terminals avoid packet collision by using two kinds of delay so that the system becomes faster than using only a CSMA/CA system. When terminals were divided into two groups or more, we confirmed faster communication from our actual experimental results. Our proposed method was able to communicate faster than the method using only CSMA/CA according to experimental results using 16 end‐devices, with a speed increase of 40% or more. Furthermore, we propose an autonomous grouping method using RSSI for the autonomous decentralized network. Our proposed method using RSSI was faster than the method using only CSMA/CA according to actual experimental results, with a speed increase of more than 25%. Thus, we have established an autonomous grouping method for TGD based on our proposed method. © 2012 Wiley Periodicals, Inc. Electron Comm Jpn, 95(6): 41–51, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10429
Optimal mapping of torus self‐organizing map for human forearm motion discrimination on the basis of myoelectric signals
Authors: Kiso Atsushi , Seki Hirokazu
Published: May 2012

This paper describes an optimal mapping of the torus self‐organizing map for human forearm motion discrimination on the basis of myoelectric signals. This study uses the torus self‐organizing map (torus SOM) for motion discrimination. The normal SOM identifies input data of the same feature group by using all units of the map. But there is then a possibility of misrecognition of motion around the boundary lines of the motion groups. Therefore, this study proposes a mapping method of SOM in which learning units of the same motion concentrate on one local range and the learning unit groups of each motion are sufficiently separated. As a result, the variance in the same motion group becomes small and the variance between motion groups becomes large. Experiments on a myoelectric hand simulator show the effectiveness of the proposed motion discrimination method. © 2012 Wiley Periodicals, Inc. Electron Comm Jpn, 95(6): 24–31, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11369
Catalase Activity of Dinuclear MnIII Compounds with Chlorobenzoato Bridges
Authors: Gómez Verónica , Corbella Montserrat
Published: May 2012

Three dinuclear MnIII compounds [{Mn(H2O)(NN)}2(μ‐3‐ClC6H4COO)2(μ‐O)]X2 with NN = 2,2′‐bipyridine (bpy; 1 and 2) or 1,10‐phenanthroline (phen; 3) and X = NO3– (1) or ClO4– (2 and 3) have been synthesized. The X‐ray structures of compounds 1 and 3 were solved and the magnetic properties of the three compounds analyzed. Compounds 1 and 3 showferromagnetic coupling, the J values being 11.8 and 5.7 cm–1,respectively. Compound 2 displays weak antiferromagnetic behavior with a J value of –0.23 cm–1. The catalase activity of these three compounds and that of eight analogous dinuclear MnIII compounds with 2‐ and 4‐chlorobenzoato ligands has been investigated. The presence of different ligands and counteranions allowed the analysis of their effects on the catalytic activity. It was observed that compounds with perchlorate anions show higher activity than compounds with nitrate anions and compounds with 3‐chlorobenzoato ligands are the worst catalysts. Moreover, most of these compounds show higher conversions than other compounds with analogous structures.
Capillary electrophoresis mass spectrometry with sheathless electrospray ionization for high sensitivity analysis of underivatized amino acids
Authors: Jeong Ji‐Seon , Kim Sook‐Kyung , Park Sang‐Ryoul
Published: May 2012

A high durability sheathless electrospray ionization interface of CE‐MS is applied for the sensitive analysis of underivatized amino acids. The sheathless interface was realized using an ionophore membrane‐packed electro‐conduction channel. The interface functioned well with a volatile alkaline background electrolyte (BGE) and uncoated fused‐silica capillaries for CE‐MS analysis of underivatized amino acids. High electroosmotic flow with alkaline BGE facilitated high separation efficiency (>100 000 theoretical plates) and short analysis time (<15 min). Both the short‐term stability and long‐term durability are particularly suited for routine applications. Using electrokinetic injection and the multiple reaction monitoring (MRM) mode with a triple‐quadrupole analyzer, high sensitivity was achieved, which yielded detection limits of 0.05–0.81 μM. For the quantitation of underivatized amino acids, quantification precisions (RSDs) for intra‐ and inter‐day analyses were less than 3%. Recoveries from serum were 96.3–101.8% for isotope dilution mass spectrometry (IDMS). When compared with HPLC‐IDMS for human serum samples, highly agreeable (96.9–102.0%) results were obtained with the proposed CE‐IDMS method.
Determination of nicotinyl pesticide residues in vegetables by micellar electrokinetic capillary chromatography with quantum dot indirect laser‐induced fluorescence
Authors: Chen Guan‐Hua , Sun Juan , Dai Yong‐Jia , Dong Min
Published: May 2012

A new assay was developed by use of micellar electrokinetic capillary chromatography with indirect LIF fluorescence for the determination of thiamethoxam, acetamiprid, and imidacloprid residues in vegetables, in which the cadmium telluride quantum dots (QDs) synthesized in aqueous phase were used as fluorescent background substance and their excitation and emission wavelengths matched with LIF detector by engineering their size. The factors that affected the peak height and the resolution were optimized. The running buffer was composed of 4.4 μM cadmium telluride QDs as fluorescent background substance, 40 mM borate and 60 mM SDS, and its pH was adjusted to 8.0. The separation voltage was 25 kV. Under the optimum conditions, the detection limits were 0.05, 0.01, and 0.009 mg/kg; the linear dynamic ranges were 0.5–30, 0.1–30, and 0.1–30 mg/L; and the average recoveries of spiked samples were 72.0–101.2, 74.0–106.7, and 77.8–105.1% for thiamethoxam, acetamiprid, and imidacloprid, respectively. The assay can meet the requirement of maximum residue limits to these three pesticides in the regulations of European Union and Japan, and has been applied for determining their residues in vegetables.
The influence of the temperature regime on the formation of methane in a two‐phase anaerobic digestion process
Authors: Schönberg Mandy , Linke Bernd
Published: May 2012

The influence of different temperature levels on the formation of methane in a two‐phase anaerobic digestion process using rye silage and barley straw as feedstocks was investigated in this study. This process comprised a leach‐bed reactor (LBR), a reservoir for leachate from the LBR, and a separate downstream fixed‐film anaerobic filter (AF), with immobilized micro biocoenosises. The degree of degradation of the volatile solids was similar in both studies and was almost equal at 75 Ma.‐%VS. When both reactor phases were operated at thermophilic conditions, the main substrate turnover was observed in the LBR (58% of the total methane yield, with an average methane content of 41 Vol.‐%). Only the excess of organic fraction in the process‐liquid was transformed in the AF (42% of the total methane yield, with an average methane content of 74 Vol.‐%). When the parts of the reactor system operated at different temperature regimes, thermophilic hydrolysis/acidogenesis phase and mesophilic methanization, a separation of carbon dioxide and methane production, was observed. A total methane yield of 88%, with an average methane content of 85 Vol.‐%, was formed in the AF. The generated biogas with high methane concentrations is suitable for feeding the purified biomethane into the natural gas grid. Furthermore, it can be used as fuel for cars and tractors.
Overpotential Behavior of Carbon Monoxide Fuel in a Molten Carbonate Fuel Cell
Authors: Lee C.‐G.
Published: May 2012

The overpotential of carbon monoxide (CO) fuel was analyzed with a 100‐cm2 class molten carbonate fuel cell. The overpotential at the anode was measured using the steady state polarization, inert gas step addition, and reactant gas addition methods. Then, the overpotential was compared between normal hydrogen fuel (H2:CO2:H2O = 0.69:0.17:0.14 atm, inlet composition) and CO fuels (CO:CO2:H2O = 0.5:0.5:0 atm and 0.43:0.43:0.14 atm, inlet compositions). The CO fuel without H2O showed a much greater overpotential at 150 mA cm–2 than the CO fuel with H2O. This implies that the water‐gas‐shift reaction prevails at the anode and humidification of CO fuel is an efficient way to reduce anodic overpotential. The anodic overpotential with CO:CO2:H2O = 0.43:0.43:0.14 atm was about 73% of that of the H2 fuel at 150 mA cm–2. The anode showed gas‐phase mass‐transfer limitations with CO fuels.
A General Protocol for the Synthesis of Pt–Sn/C Catalysts for the Ethanol Electrooxidation Reaction
Authors: Liu B. , Chia Z.‐W. , Lee Z.‐Y. , Cheng C.‐H. , Lee J.‐Y. , Liu Z.‐L.
Published: May 2012

A general protocol for the synthesis of Pt–Sn/C catalysts for ethanol electrooxidation by the polyol method is developed after a systematic variation of the preparation variables. This protocol enables the complete transfer of all catalytic elements in the preparation solution to the catalyst support; thereby providing a convenient means of catalyst composition control. Water is a necessary co‐solvent for ethylene glycol in the polyol synthesis of Pt–Sn/C catalysts. The best preparation medium for controlling the particle size to small sizes is 0.1 M NaOH solution in a mixture of equal volumes of water and ethylene glycol. With this medium composition Pt–Sn/C catalysts with the optimized target Pt:Sn atomic ratio of 3:1 could be expeditiously prepared for ethanol electrooxidation.
GAS41 amplification results in overexpression of a new spindle pole protein
Authors: Schmitt Jana , Fischer Ulrike , Heisel Sabrina , Strickfaden Hilmar , Backes Christina , Ruggieri Alessia , Keller Andreas , Chang Paul , Meese Eckart
Published: May 2012

Amplification is a hallmark of many human tumors but the role of most amplified genes in human tumor development is not yet understood. Previously, we identified a frequently amplified gene in glioma termed glioma‐amplified sequence 41 (GAS41). Using the TCGA data portal and performing experiments on HeLa and TX3868, we analyzed the role of GAS41 amplification on GAS41 overexpression and the effect on the cell cycle. Here we show that GAS41 amplification is associated with overexpression in the majority of cases. Both induced and endogenous overexpression of GAS41 leads to an increase in multipolar spindles. We showed that GAS41 is specifically associated with pericentrosome material. As result of an increased GAS41 expression we found bipolar spindles with misaligned chromosomes. This number was even increased by a combined overexpression of GAS41 and a reduced expression of NuMA. We propose that GAS41 amplification may have an effect on the highly altered karyotype of glioblastoma via its role during spindle pole formation. © 2012 Wiley Periodicals, Inc.
The application of fallout radionuclides to determine the dominant erosion process in water supply catchments of subtropical South‐east Queensland, Australia
Authors: Olley Jon , Burton Joanne , Smolders Kate , Pantus Francis , Pietsch Timothy
Published: May 2012

Previous studies using fallout radionuclides (137Cs and 210Pbex) to determine the relative contributions of surface‐soil and channel erosion (including gullies and channel banks) to stream sediments have used a relatively small number of composite samples (<25) to characterize the source end members, and concentrations in each of the source end members have, through the use of means and standard errors, been assumed to be normally distributed. Here, we examine 137Cs activity concentrations to determine the erosion processes supplying sediment in seven water supply catchments in South‐east Queensland. First, we test some of the underlying assumptions in the method using concentrations of 137Cs and 210Pbex in composite samples collected from 109 surface‐soil sites and 39 channel‐bank sites. Paired composite samples, each consisting of 20 subsamples, from five sites are used to demonstrate that this sampling approach was sufficient to average out any local variations in surface‐soil 210Pbex and 137Cs concentrations across the 300 m2 sampled. We derive probability distributions for 137Cs and 210Pbex concentrations in the group of samples from each of the end members and show that only the distribution of 210Pbex in samples from surface soils is normally distributed. We use the probability distributions for 137Cs, which provides the greatest discrimination between sources, to show that the 137Cs concentrations on the river sediment samples are consistent with channel erosion being the dominant source. Conservation works aimed at reducing the supply of sediments in these catchments should therefore focus on rehabilitation of the channel network and decreasing the runoff to the channel network. These findings are consistent with other similar studies on tropical Australian rivers. Copyright © 2012 John Wiley & Sons, Ltd.
NOS2 enhances KRAS‐induced lung carcinogenesis, inflammation and microRNA‐21 expression
Authors: Okayama Hirokazu , Saito Motonobu , Oue Naohide , Weiss Jonathan M. , Stauffer Jimmy , Takenoshita Seiichi , Wiltrout Robert H. , Hussain S. Perwez , Harris Curtis C.
Published: May 2012

Mutant KRAS in lung cancers induces molecular pathways that regulate cellular proliferation, survival and inflammation, which enhance tumorigenesis. Inducible nitric oxide synthase (NOS2) upregulation and sustained nitric oxide generation are induced during the inflammatory response and correlate positively with lung tumorigenesis. To explore the mechanistic contribution of NOS2 to KRAS‐induced lung tumorigenesis and inflammation, we used a genetic strategy of crossing NOS2 knockout (NOS2KO) C57BL6 inbred mice with a KRASG12D‐driven mouse lung cancer model. KRASG12D;NOS2KO mice exhibited delayed lung tumorigenesis and a longer overall survival time compared to that of KRASG12D;NOS2WT (wild‐type) controls. Correspondingly, tumors in KRASG12D;NOS2KO mice had reduced tumor cell proliferation in adenomas and carcinomas. NOS2 deficiency also led to markedly suppressed inflammatory response by attenuation of macrophage recruitment into alveoli and within tumor foci. In contrast, FOXP3+ regulatory T cells were increased in tumors from KRASG12D;NOS2KO mice. We further analyzed the expression of microRNA‐21 (miR‐21), an oncogenic noncoding RNA involved in oncogenic Ras signaling, by quantitative reverse‐transcription polymerase chain reaction and in situ hybridization. Lung carcinomas dissected from KRASG12D;NOS2KO mice showed a significantly reduced miR‐21 expression along with decreased tumor cell proliferation, suggesting that NOS2 deficiency could attenuate RAS signaling pathways that transactivate miR‐21 expression. Therefore, deletion of NOS2 decreases lung tumor growth as well as inflammatory responses initiated by oncogenic KRAS, suggesting that both KRAS and NOS2 cooperate in driving lung tumorigenesis and inflammation. Inhibition of NOS2 may have a therapeutic value in lung cancers with oncogenic KRAS mutations.
Abdominal obesity, weight gain during adulthood and risk of liver and biliary tract cancer in a European cohort
Authors: Schlesinger Sabrina , Aleksandrova Krasimira , Pischon Tobias , Fedirko Veronika , Jenab Mazda , Trepo Elisabeth , Boffetta Paolo , Dahm Christina C. , Overvad Kim , Tjønneland Anne , Halkjær Jytte , Fagherazzi Guy , Boutron‐Ruault Marie‐Christine , Carbonnel Franck , Kaaks Rudolf , Lukanova Annekatrin , Boeing Heiner , Trichopoulou Antonia , Bamia Christina , Lagiou Pagona , Palli Domenico , Grioni Sara , Panico Salvatore , Tumino Rosario , Vineis Paolo , HB Bueno‐de‐Mesquita , van den Berg Saskia , Peeters Petra H.M. , Braaten Tonje , Weiderpass Elisabete , Quirós J. Ramón , Travier Noémie , Sánchez María‐José , Navarro Carmen , Barricarte Aurelio , Dorronsoro Miren , Lindkvist Björn , Regner Sara , Werner Mårten , Sund Malin , Khaw Kay‐Tee , Wareham Nicholas , Travis Ruth C. , Norat Teresa , Wark Petra A. , Riboli Elio , Nöthlings Ute
Published: May 2012

General obesity has been positively associated with risk of liver and probably with biliary tract cancer, but little is known about abdominal obesity or weight gain during adulthood. We used multivariable Cox proportional hazard models to investigate associations between weight, body mass index, waist and hip circumference, waist‐to‐hip and waist‐to‐height ratio (WHtR), weight change during adulthood and risk of hepatocellular carcinoma (HCC), intrahepatic (IBDC) and extrahepatic bile duct system cancer [EBDSC including gallbladder cancer (GBC)] among 359,525 men and women in the European Prospective Investigation into Cancer and Nutrition study. Hepatitis B and C virus status was measured in a nested case–control subset. During a mean follow‐up of 8.6 years, 177 cases of HCC, 58 cases of IBDC and 210 cases of EBDSC, including 76 cases of GBC, occurred. All anthropometric measures were positively associated with risk of HCC and GBC. WHtR showed the strongest association with HCC [relative risk (RR) comparing extreme tertiles 3.51, 95% confidence interval (95% CI): 2.09–5.87; ptrend < 0.0001] and with GBC (RR: 1.56, 95% CI: 1.12–2.16 for an increment of one unit in WHtR). Weight gain during adulthood was also positively associated with HCC when comparing extreme tertiles (RR: 2.48, 95% CI: 1.49–4.13; <0.001). No statistically significant association was observed between obesity and risk of IBDC and EBDSC. Our results provide evidence of an association between obesity, particularly abdominal obesity, and risk of HCC and GBC. Our findings support public health recommendations to reduce the prevalence of obesity and weight gain in adulthood for HCC and GBC prevention in Western populations.
Vertebral fragility and structural redundancy
Authors: Fields Aaron J , Nawathe Shashank , Eswaran Senthil K , Jekir Michael G , Adams Mark F , Papadopoulos Panayiotis , Keaveny Tony M
Published: May 2012

The mechanisms of age-related vertebral fragility remain unclear, but may be related to the degree of “structural redundancy” of the vertebra; ie, its ability to safely redistribute stress internally after local trabecular failure from an isolated mechanical overload. To better understand this issue, we performed biomechanical testing and nonlinear micro-CT–based finite element analysis on 12 elderly human thoracic ninth vertebral bodies (age 76.9 ± 10.8 years). After experimentally overloading the vertebrae to measure strength, we used nonlinear finite element analysis to estimate the amount of failed tissue and understand the failure mechanisms. We found that the amount of failed tissue per unit bone mass decreased with decreasing bone volume fraction (r2 = 0.66, p < 0.01). Thus, for the weak vertebrae with low bone volume fraction, overall failure of the vertebra occurred after failure of just a tiny proportion of the bone tissue (<5%). This small proportion of failed tissue had two sources: the existence of fewer vertically oriented load paths to which load could be redistributed from failed trabeculae; and the vulnerability of the trabeculae in these few load paths to undergo bending-type failure mechanisms, which further weaken the bone. Taken together, these characteristics suggest that diminished structural redundancy may be an important aspect of age-related vertebral fragility: vertebrae with low bone volume fraction are highly susceptible to collapse because so few trabeculae are available for load redistribution if the external loads cause any trabeculae to fail. © 2012 American Society for Bone and Mineral Research.
Intermittent parathyroid hormone administration converts quiescent lining cells to active osteoblasts
Authors: Kim Sang Wan , Pajevic Paola Divieti , Selig Martin , Barry Kevin J , Yang Jae-Yeon , Shin Chan Soo , Baek Wook-Young , Kim Jung-Eun , Kronenberg Henry M
Published: May 2012

Intermittent administration of parathyroid hormone (PTH) increases bone mass, at least in part, by increasing the number of osteoblasts. One possible source of osteoblasts might be conversion of inactive lining cells to osteoblasts, and indirect evidence is consistent with this hypothesis. To better understand the possible effect of PTH on lining cell activation, a lineage tracing study was conducted using an inducible gene system. Dmp1-CreERt2 mice were crossed with ROSA26R reporter mice to render targeted mature osteoblasts and their descendents, lining cells and osteocytes, detectable by 5-bromo-4-chloro-3-indolyl-β-d-galactopyranoside (X-gal) staining. Dmp1-CreERt2(+):ROSA26R mice were injected with 0.25 mg 4-OH-tamoxifen (4-OHTam) on postnatal days 3, 5, 7, 14, and 21. The animals were euthanized on postnatal day 23, 33, or 43 (2, 12, or 22 days after the last 4-OHTam injection). On day 43, mice were challenged with a subcutaneous injection of human PTH (1–34, 80 µg/kg) or vehicle once daily for 3 days. By 22 days after the last 4-OHTam injection, most X-gal (+) cells on the periosteal surfaces of the calvaria and the tibia were flat. Moreover, bone formation rate and collagen I(α1) mRNA expression were decreased at day 43 compared to day 23. After 3 days of PTH injections, the thickness of X-gal (+) cells increased, as did their expression of osteocalcin and collagen I(α1) mRNA. Electron microscopy revealed X-gal–associated chromogen particles in thin cells prior to PTH administration and in cuboidal cells following PTH administration. These data support the hypothesis that intermittent PTH treatment can increase osteoblast number by converting lining cells to mature osteoblasts in vivo. © 2012 American Society for Bone and Mineral Research.
Targeting the E3 ubiquitin casitas B-lineage lymphoma decreases osteosarcoma cell growth and survival and reduces tumorigenesis
Authors: Sévère Nicolas , Dieudonné François-Xavier , Marty Caroline , Modrowski Dominique , Patiño-García Ana , Lecanda Fernando , Fromigué Olivia , Marie Pierre J
Published: May 2012

Targeting receptor tyrosine kinase (RTK) degradation may be an interesting approach to reduce RTK cell signaling in cancer cells. Here we show that increasing E3 ubiquitin ligase casitas B-lineage lymphoma (c-Cbl) expression using lentiviral infection decreased osteosarcoma cell replication and survival and reduced cell migration and invasion in murine and human osteosarcoma cells. Conversely, c-Cbl inhibition using short hairpin RNA (shRNA) increased osteosarcoma cell growth and survival, as well as invasion and migration, indicating that c-Cbl plays a critical role as a bone tumor suppressor. Importantly, the anticancer effect of increasing c-Cbl expression in osteosarcoma cells was related mainly to the downregulation of epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor alpha (PDGFRα). In a murine bone tumor model, increasing c-Cbl expression also reduced RTK expression, resulting in decreased tumor cell proliferation and survival and reduced tumor growth. Interestingly, increasing c-Cbl also markedly reduced lung metastasis in mice. Tissue microarray analysis revealed that low c-Cbl protein expression is associated with elevated EGFR and PDGFRα protein levels in human osteosarcoma with poor outcome. This study shows that increasing c-Cbl expression reduces osteosarcoma cell growth, survival, and metastasis in part through downregulation of RTKs, which supports the potential therapeutic interest of targeting c-Cbl in malignant bone diseases involving increased RTK. © 2012 American Society for Bone and Mineral Research.
Nuclear magnetic resonance J coupling constant polarizabilities of hydrogen peroxide: A basis set and correlation study
Authors: Kjær Hanna , Nielsen Monia R. , Pagola Gabriel I. , Ferraro Marta B. , Lazzeretti Paolo , P. A. Sauer Stephan
Published: May 2012

In this article, we present the so far most extended investigation of the calculation of the coupling constant polarizability of a molecule. The components of the coupling constant polarizability are derivatives of the nuclear magnetic resonance (NMR) indirect nuclear spin–spin coupling constant with respect to an external electric field and play an important role for both chiral discrimination and solvation effects on NMR coupling constants. In this study, we illustrate the effects of one‐electron basis sets and electron correlation both at the level of density functional theory as well as second‐order polarization propagator approximation for the small molecule hydrogen peroxide, which allowed us to perform calculations with the largest available basis sets optimized for the calculation of NMR coupling constants. We find a systematic but rather slow convergence with the one‐electron basis set and that augmentation functions are required. We observe also large and nonsystematic correlation effects with significant differences between the density functional and wave function theory methods. © 2012 Wiley Periodicals, Inc.
Quantum chemical insights into the aggregation induced emission phenomena: A QM/MM study for pyrazine derivatives
Authors: Wu Qunyan , Deng Chunmei , Peng Qian , Niu Yingli , Shuai Zhigang
Published: May 2012

There have been intensive studies on the newly discovered phenomena called aggregation induced emission (AIE), in contrast to the conventional aggregation quenching. Through combined quantum mechanics and molecular mechanics computations, we have investigated the aggregation effects on the excited state decays, both via radiative and nonradiative routes, for pyrazine derivatives 2,3‐dicyano‐5,6‐diphenylpyrazine (DCDPP) and 2,3‐dicyanopyrazino phenanthrene (DCPP) in condensed phase. We show that for DCDPP there appear AIE for all the temperature, because the phenyl ring torsional motions in gas phase can efficiently dissipate the electronic excited state energy, and get hindered in aggregate; while for its “locked”‐phenyl counterpart, DCPP, theoretical calculation can only give the normal aggregation quenching. These first‐principles based findings are consistent with recent experiment. The primary origin of the exotic AIE phenomena is due to the nonradiative decay effects. This is the first time that AIE is understood based on theoretical chemistry calculations for aggregates, which helps to resolve the present disputes over the mechanism. © 2012 Wiley Periodicals, Inc.
On the Existence of Simple BIBDs with Number of Elements a Prime Power
Authors: Sun Hsin-Min
Published: May 2012

We show that, when the number of elements is a prime power q, in many situations the necessary conditions

,

, and

are also sufficient for the existence of a simple balanced incomplete block design.
Regenerative cells and the architecture of beetle midgut epithelia
Authors: Nardi James B. , Bee Charles Mark
Published: May 2012

The architectural ground plan of beetle and other insect midguts is represented by a monolayer of epithelial cells arranged in a cylindrical configuration. Proliferation and differentiation of regenerative cells maintain the integrity of this monolayer in the face of continual losses of individual cells through cytoplasmic budding and/or expulsion of entire epithelial cells. Peritrophic membranes have conventionally been considered universal features of insect midguts that function to protect vulnerable microvillar surfaces of the midgut epithelium from abrasion by ingested food; however, peritrophic membranes were found in only a small fraction of the adult beetle species examined in this study. In adult beetles, midgut epithelial cells are continually replaced by cells recruited from populations of mitotic regenerative cells that are interspersed among the differentiated epithelial monolayer. To remain contiguous with the other cells in the midgut monolayer, some of these proliferating populations have adopted evaginated configurations of cells that extend for varying distances from the basal surface of the monolayer. These configurations are referred to as regenerative crypts or pouches and consist of progenitor cells and stem cells. The presence, the relative densities, and the relative lengths of these regenerative pouches vary considerably among families of beetles. Placement of longitudinal muscles of the midgut relative to the proximodistal axes of these regenerative pouches also varies among species of beetles. The presence, the size, and the density of regenerative cell populations are related to 1) feeding habits of adult beetles, 2) presence of peritrophic membranes, and 3) expulsion of entire midgut epithelial cells or fragments of these epithelial cells into midgut lumens. © 2012 Wiley Periodicals, Inc.
Age and innovation‐related behavior: The joint moderating effects of supervisor undermining and proactive personality
Authors: Ng Thomas W. H. , Feldman Daniel C.
Published: May 2012

Previous research has yielded mixed results regarding the effects of age on innovation‐related behavior (IRB; i.e., generating, disseminating, and implementing new ideas). This paper hypothesizes that the relationship of age with IRB is jointly moderated by undermining behavior on the part of the supervisor and the extent to which the employee possesses a proactive personality. We collected data from 196 employees at three points in time over a one‐year period. Results supported the hypothesized 3‐way interaction of age, supervisor undermining, and proactive personality on IRB. As predicted, highly proactive older workers responded to high supervisor undermining with more IRB, whereas older workers low on proactive personality responded to high supervisor undermining with less IRB. On the other hand, when supervisor undermining was low, proactive personality did not moderate the relationship of age with IRB. Copyright © 2012 John Wiley & Sons, Ltd.