bluuebunny/crossref_metadata_2025 huggingface dataset:
Fatigue damage initiation of a PA66/glass fibers composite material
Authors: Esmaeillou B. , Fereirra P. , Bellenger V. , Tcharkhtchi A.
Published: March 2012

Fatigue damage initiation of a PA66/glass fiber composite material is studied with interrupted tests carried out with an “alternative bending device” and a small applied strain. During the damage initiation period, no change of macroscopic properties, density, cristallinity ratio, glass transition temperature, and flexural elastic modulus is observed. Polysequential tests are carried out with three rest times differing by their length. These rest times allow the relaxation of macromolecular chains in the region of the microdefects and increase the number of cycles at fracture. The most efficient stop is the one just before the final fracture. The comparison of the fatigue behavior of the composite and its neat matrix shows that the microdefects relaxed during the break are identical to those which initiate damage and final fracture. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of inorganic salts on viscosifying behavior of a thermoassociative water‐soluble terpolymer based on 2‐acrylamido‐methylpropane sulfonic acid
Authors: Liu Xingli , Wang Yu , Lu Zhiyong , Chen Quansheng , Feng Yujun
Published: March 2012

The effect of different inorganic salts on aqueous solution viscosifying behavior of a thermoassociative water‐soluble terpolymer, poly(acrylamide‐co‐2‐acrylamido‐2‐methylpropane sulfonic acid)‐g‐poly[acrylamide‐co‐N‐(1,1‐dimethyl‐3‐oxobutyl)acrylamide] (PADAS) was examined in comparison with a nonthermoassociative sulfonated copolymer, poly(acrylamide‐co‐2‐acrylamido‐2‐methylpropane sulfonic acid) (PAMS). With increasing salt concentration, thermoviscosifying ability of PADAS was clearly evidenced and the magnitude of thermoviscosifying effect was largely enhanced. The ability of cations and anions to enhance the viscosity of PADAS aqueous solution follows the orders Na+ > K+ > Mg2+ > Ca2+ and SO42− > Cl− > Br‐ > NO3−, respectively. Under the same conditions, PAMS shows only thermothinning behavior and viscosity loss. The thermoviscosifying capability of PADAS is relevant to the change in the polarity of aqueous solution and the electrostatic shield effect of counterion for the repulsion between the sulfonate anions on the polymer, and depends mainly on the competition of these two effects. Cryo‐TEM observation demonstrates that the microstructure changes of polymers in the electrolyte solution lead to the changes of the viscosifying behavior. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Formation of a metastable phase of bisphenol‐A polycarbonate induced by mechanical stress
Authors: Matsuda Yasuhiro , Hanamura Rei , Takemura Yoshinobu , Sugita Atsushi , Tasaka Shigeru
Published: March 2012

Samples of bisphenol‐A polycarbonate (BPA‐PC) mechanically crushed in a ballmill were prepared and their physical properties were analyzed in order to elucidate the mechanism of the high impact resistivity of polycarbonates, which makes polycarbonates to be widely used engineering plastics. In this article, BPA‐PC samples were prepared with different surface conditions to probe their molecular mobility. While BPA‐PC films prepared by melt pressing showed a single glass transition at 150°C, the samples crushed in a ballmill, ground in a mortar with added alumina powder, or cast from solution in tetrahydrofuran showed glass transitions at approximately room temperature. The existence of glass transition behavior at room temperature was confirmed for the mechanically crushed samples by differential scanning calorimetry, dielectric relaxation measurements, and friction measurements. The independence of the glass transition of mechanically crushed BPA‐PC on molecular weight indicated that the chain ends do not play an important role in the glass transition behavior. The molecular structures of the films were also investigated by infrared spectroscopy. The relationship between this unique glass transition behavior and the high impact resistivity of BPA‐PC is discussed based on the experimental results. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
DIFFERENTIAL EXPRESSION OF THE Bombyx mori DIAPAUSE‐TERMINATION TIMER GENE Ea4 IN DIAPAUSE‐INDUCING TEMPERATURE AND PHOTOPERIOD
Authors: Xu Li , Liang Hui , Niu Yanshan , Wang Ying , Sima Yanghu , Xu Shiqing
Published: March 2012

Diapause in Bombyx mori eggs is induced by temperature and photoperiod at the stage of embryonic development in the maternal generation. In those diapause eggs, Esterase‐A4 is suggested to serve as a diapause‐termination timer (TIME‐EA4), because its ATPase activity shows an interval‐timer elevation after acid treatment or chilling of eggs to break diapause. To clarify whether the timed ATPase activity of TIME‐EA4 is related to its gene (Ea4) expression, we analyzed Ea4 mRNA of eggs in diapause‐inducing environmental conditions. Reverse transcription PCR (RT‐PCR) analysis showed that the level of Ea4 mRNA was lower in 15DD than in 25LL (P < 0.01) or in 20LD (P < 0.01) but did not oscillate when photoperiod and temperature periodically oscillated (P > 0.05). Furthermore, expressed sequence tag profile and gene microarray analysis demonstrated that Ea4 showed stage‐specific and tissue‐specific expression during postembryonic stages, high Ea4 mRNA in the spinning and eclosion stages, and in integument and head, but low in gonads of fifth‐instar day‐3 larvae. Then we analyzed the relationship between TIME‐EA4 ATPase activities and Ea4 gene expression. The ATPase activities in diapause eggs laid by the resultant adults transiently elevated after treatments to break diapause, that is, at 1.5 h after common‐acid treatment and day 13 after chilling at 5°C. However, these elevations of enzyme activities were not accompanied by any increases in Ea4 mRNA levels. In conclusion, the termination of the Bombyx embryonic diapause is related to TIME‐EA4 but not to its gene expression.
Assessment of the Effect of Instrumental and Discretization Errors on Derivative‐based Potential‐field Geophysical Methods
Authors: Milea Christian M. , Papazachos Constantinos B. , Tsokas Gregory N. , Tsourlos Panagiotis I.
Published: March 2012

Geophysical field measurements are subject to errors, which consequently comprise part of the data and subsequently they are propagated through processing techniques. Some of these errors can be controlled and eliminated, but others such as the errors introduced by the measuring instrument cannot be avoided. Moreover, the field data are collected as discrete samples, a procedure that introduces errors by itself. These two types of error are examined in the present study regarding their propagation and influence in estimating derivatives and subsequently functions of derivatives, such as the complex attributes. For this reason we consider magnetic anomalies (signals) of typical buried structures that are common in archaeological prospection, such as concealed ditches. In order to have analytical expressions for the magnetic anomaly signal, the structures are simulated by polygonal bodies. The magnetic anomaly signals are subsequently discretized and anomaly derivatives as well as complex attributes are computed using numerical methods. These discrete function values are compared with the corresponding values obtained from the analytical solutions in order to assess the discretization errors involved. Similarly, calculations are repeated after contaminating the signals with Gaussian noise in an attempt to simulate the effect of instrumental error. A parametric study of these two error sources is performed, showing that they have a contradictory effect: larger sampling intervals increase, as expected, the numerical divergence of ideal data (no noise) from their analytical form. On the other hand, for realistic data (with random noise) the increase of the measuring step decreases the effect of instrument error. The combined influence of both sources of errors shows that the various derivative‐based measures exhibit a minimum of the introduced total error for different combinations of discretization and measurement errors. The quantitative study of the combined error provides useful suggestions on the best way that magnetic surveys should be carried out when the use of derivatives is employed for the final data interpretation. Copyright © 2012 John Wiley & Sons, Ltd.
Distinct roles for complement in glomerulonephritis and atherosclerosis revealed in mice with a combination of lupus and hyperlipidemia
Authors: Lewis Myles J. , Malik Talat H. , Fossati‐Jimack Liliane , Carassiti Daniele , Cook H. Terence , Haskard Dorian O. , Botto Marina
Published: March 2012

Objective

Although the accelerating effect of systemic lupus erythematosus (SLE) on atherosclerosis is well established, the underlying mechanisms are unknown. The aim of this study was to explore the hypothesis that lupus autoimmunity modulates the effect of hypercholesterolemia in driving arterial pathologic development.

Methods

Low‐density lipoprotein receptor–deficient (Ldlr−/−) mice were crossed with B6.129‐Sle16 (Sle16)–congenic autoimmune mice to obtain Sle16. Ldlr−/− mice, which were compared with Ldlr−/− and Sle16 control mice. All mice were fed either a low‐fat or high‐fat diet. Groups of mice were compared, by strain and by diet group, for features of accelerated atherosclerosis and autoimmunity.

Results

Presence of the Sle16 locus significantly increased the extent of atherosclerosis in Ldlr−/− mice. Circulating C3 levels were significantly reduced in Sle16.Ldlr−/− mice compared to Ldlr−/− control mice and this was paralleled by a marked reduction in arterial lesion C3 deposition despite similar levels of IgG deposition between the groups. Increased numbers of apoptotic cells in plaques were observed in the high‐fat–fed Sle16.Ldlr−/− mice, consistent with the observed defective clearance of cellular debris. After receiving the high‐fat diet, Sle16.Ldlr−/− mice developed glomerulonephritis and displayed enhanced glomerular C3 deposition.

Conclusion

These results indicate that accelerated atherosclerosis and renal inflammation in SLE are closely linked via immune complex formation and systemic complement depletion. However, whereas hyperlipidemia will enhance renal immune complex–mediated complement activation and the development of nephritis, accelerated atherosclerosis is, instead, related to complement depletion and a reduction in the uptake of apoptotic/necrotic debris. These results suggest that aggressive treatment of hyperlipidemia in patients with SLE may reduce the occurrence of lupus nephritis, as well as diminish the risk of accelerated atherosclerosis.
Personal health record architectures: Technology infrastructure implications and dependencies
Authors: Steele Robert , Min Kyongho , Lo Amanda
Published: March 2012

The existing literature in relation to electronic personal health records (PHRs) has typically focused on the discussion of several key issues—namely, their design, functional evaluation, privacy, security and architecture. The benefits of PHRs and barriers preventing their adoption are also widely discussed. These issues are affected by technology infrastructure, and current and planned technology infrastructure deployment will be key determinants in the selection and design of PHR architectures. Assumptions about the community‐wide deployment of required technologies such as hardware and internet accessibility are implicit in the architectural selection of PHRs and these dependencies have not been fully appreciated or addressed in the existing literature. This review article introduces and describes two infrastructural drivers—ubiquitous technology baseline for PHRs and connectivity coverage—and examines their inter‐relationships with the selected PHR architectures. Eleven functional capabilities are also described, providing a basis for the analysis of the relationships between the two infrastructural drivers and architectural selection.
A fuzzy stochastic approach to the multicriteria selection of an aircraft for regional chartering
Authors: Gomes Luiz Flavio Autran Monteiro , de Mattos Fernandes Joao Erick , de Mello João Carlos C. B. Soares
Published: March 2012

This article deals with the problem of decision support for the selection of an aircraft. This is a problem faced by an airline company that is investing in regional charter flights in Brazil. The company belongs to an economic group whose core business is logistics. The problem has eight alternatives to be evaluated under 11 different criteria, whose measurements can be exact, stochastic, or fuzzy. The technique chosen for analyzing and then finding a solution to the problem is the multicriteria decision aiding method named NAIADE (Novel Approach to Imprecise Assessment and Decision Environments). The method used allows tackling the problems by working with quantitative as well as qualitative criteria under uncertainty and imprecision. Another considerable advantage of NAIADE over other multicriteria methods relies in its characteristics of not requiring a prior definition of the weights by the decision maker. As a conclusion, it can be said that the use of NAIADE provided for consistent results to that aircraft selection problem. Copyright © 2012 John Wiley & Sons, Ltd.
Beyond the connectome: How neuromodulators shape neural circuits
Authors: Bargmann Cornelia I.
Published: March 2012

Powerful ultrastructural tools are providing new insights into neuronal circuits, revealing a wealth of anatomically‐defined synaptic connections. These wiring diagrams are incomplete, however, because functional connectivity is actively shaped by neuromodulators that modify neuronal dynamics, excitability, and synaptic function. Studies of defined neural circuits in crustaceans, C. elegans, Drosophila, and the vertebrate retina have revealed the ability of modulators and sensory context to reconfigure information processing by changing the composition and activity of functional circuits. Each ultrastructural connectivity map encodes multiple circuits, some of which are active and some of which are latent at any given time.
Dynamic Heat Transfer Characteristics Modeling of Microencapsulated Phase Change Material Slurries
Authors: Chen Z. , Shan F. , Fang G.‐Y.
Published: March 2012

Convective heat transfer characteristics of microencapsulated phase change material slurries (MPCSs) flowing in a circular tube under constant heat flux are studied and a feasible heat transfer model is presented. The heat transfer coefficient of MPCS and the wall temperature of the circular tube are simulated. The simulation results agree qualitatively with the experimental results. The effects of Stefan (Ste) number, mass concentration, phase change temperature range, and Reynolds (Re) number on heat transfer characteristics are discussed. The results indicate that the Ste‐number and mass fraction are the most important parameters influencing heat transfer properties compared to the phase change temperature range and Re‐number which less affect these characteristics.
Construction of lattice‐Boltzmann schemes for non‐Newtonian and two‐phase flows
Authors: Vikhansky A.
Published: March 2012

In the present study we consider a general algebraically tractable approach to the construction of lattice‐Boltzmann (LB) schemes for the simulation of non‐Newtonian and two‐phase flows. The chain of moment equations is truncated at a level corresponding to the rheology of the liquid, and is closed by a Chapman–Enskog procedure. The collision term of the LB method is linked to the second moment of the velocity distribution via the constitutive equation of the liquid. The resulting nonlinear algebraic equation can be efficiently solved for an arbitrary rheological law. The algorithm can be extended to a two‐phase system.
The influence of Büttiker probe scattering to the port behavior of nanoscale metal–oxide–semiconductor devices
Authors: Xiong Jian , Wang Gen , Mathis Wolfgang
Published: March 2012

This paper presents a discussion of the impact of Büttiker probe scattering on the port behavior of nanoscaled metal–oxide–semiconductor devices. The simulation of the carrier transport property is based on the nonequilibrium Green's function formalisms, and scattering effects are implemented in the model through Büttiker probes. For reducing the computational burden, a simplified model for modeling the scattering effects with only one Büttiker probe is proposed and gives reasonable results for studying the port behaviors of nanoscaled metal–oxide–semiconductor devices. Copyright © 2012 John Wiley & Sons, Ltd.
Remote Plasma‐Assisted CVD Growth of Carbon Nanotubes in an Optimised Rapid Thermal Reactor
Authors: Peltekis Nikos , Mausser Marcel , Kumar Shishir , McEvoy Niall , Murray Chris , Duesberg Georg S.
Published: March 2012

The advances in the use of a remote plasma in combination with a rapid radiative reactor in plasma‐enhanced (PE) CVD is presented here. The characteristics and parameters of this system are fully analyzed and compared with conventional CVD growth methods. Growth of multi‐ and single‐walled carbon nanotubes (CNTs) at low temperatures with high quality and reproducibility has been achieved in this way. Further, a new catalytic system, which gives dense multi‐wall CNTs on metal substrates, is presented.
Performance evaluation of selected Transmission Control Protocol variants over a digital video broadcasting‐second generation broadband satellite multimedia system with QoS
Authors: Rendon‐Morales Elizabeth , Mata‐Díaz Jorge , Alins Juanjo , Muñoz Jose L. , Esparza Oscar
Published: March 2012

This paper presents an analysis of several Transmission Control Protocol (TCP) variants working over a digital video broadcasting‐second generation (DVB‐S2) satellite link with the support of the Differentiated Services (DiffServ) architecture to provide quality of service (QoS). This analysis is carried out using the NS‐2 simulator tool. Three TCP variants are considered: SACK TCP, Hybla TCP, and CUBIC TCP. These TCP variants are taken as a starting point because they have proven to be the most suitable variants to deal with long delays present in satellite links. The DVB‐S2 link also introduces the challenge of dealing with variable bandwidth, whereas the DiffServ architecture introduces the challenge of dealing with different priorities. In this paper, we propose a DiffServ model that includes a modified queuing mechanism to enhance the goodput of the assured forwarding traffic class. This modified DiffServ model is simulated and tested, considering the interaction of the selected TCP variants. In addition, we present evaluation metrics, significant simulations results, and conclusions about the performance of these TCP variants evaluated over the proposed scenario. As a general conclusion, we show that CUBIC TCP is the TCP variant that shows the best performance in terms of goodput, latency, and friendliness. Copyright © 2012 John Wiley & Sons, Ltd.
Heck–Matsuda Reaction for Allylic Nitro Compounds: A Short Asymmetric Synthesis of an FTY720 Derivative
Authors: Nakano Toshiki , Miyahara Mizuki , Itoh Toshiyuki , Kamimura Akio
Published: March 2012

The Heck–Matsuda reaction for allylic nitro compounds effectively afforded cinnamyl nitro compounds in good yields. Aryldiazonium salts that have an electron‐donating substituent underwent a smooth reaction in the presence of Pd2dba3. A palladium complex that coordinated with an electron‐rich ligand was necessary for the reaction to progress with electron‐deficient aryldiazonium salts. An optically active allylic nitro compound underwent reaction without the loss of optical purity at the stereogenic center. A short synthesis of an optically active FTY720 derivative was achieved by this method.
Sensitivity analysis on parameters and processes affecting vapor intrusion risk
Authors: Picone Sara , Valstar Johan , van Gaans Pauline , Grotenhuis Tim , Rijnaarts Huub
Published: March 2012

A one-dimensional numerical model was developed and used to identify the key processes controlling vapor intrusion risks by means of a sensitivity analysis. The model simulates the fate of a dissolved volatile organic compound present below the ventilated crawl space of a house. In contrast to the vast majority of previous studies, this model accounts for vertical variation of soil water saturation and includes aerobic biodegradation. The attenuation factor (ratio between concentration in the crawl space and source concentration) and the characteristic time to approach maximum concentrations were calculated and compared for a variety of scenarios. These concepts allow an understanding of controlling mechanisms and aid in the identification of critical parameters to be collected for field situations. The relative distance of the source to the nearest gas-filled pores of the unsaturated zone is the most critical parameter because diffusive contaminant transport is significantly slower in water-filled pores than in gas-filled pores. Therefore, attenuation factors decrease and characteristic times increase with increasing relative distance of the contaminant dissolved source to the nearest gas diffusion front. Aerobic biodegradation may decrease the attenuation factor by up to three orders of magnitude. Moreover, the occurrence of water table oscillations is of importance. Dynamic processes leading to a retreating water table increase the attenuation factor by two orders of magnitude because of the enhanced gas phase diffusion. Environ. Toxicol. Chem. 2012; 31: 1042–1052. © 2012 SETAC
Dynamics of suspended sediment delivery to the Eastern Mediterranean continental shelf
Authors: Vachtman Dina , Sandler Amir , Greenbaum Noam , Herut Barak
Published: March 2012

This study provides data on the fluvial sediment transport at the Eastern Mediterranean, an area in which the regional importance for comparative study has often been raised by investigators but the data are rather scarce. We analysed long‐ and short‐term hydrologic and sedimentological data from one of the largest coastal streams of Israel, Qishon River (1100 km2), and its estuarine environment. The results indicate that during 65 years (1944–2009), a total 140 floods have contributed to the sea an amount of approximately 2.58 × 106 tons of sediment. During this period, (i) the number of floods with a return period of more than 10 years has almost doubled during the last 30 years, and (ii) the mean annual discharge during last 10 years increased by approximately 175%. The analysis of the short (2 years) hydrological and sediment data revealed that approximately 30% of the upstream channel loads do not reach the river mouth and are deposited along the channel bed, even during major flood events. This observation was attributed largely to the facts that the lower river bed is incised below sea level, to the very low slopes and to the correspondingly low stream power and transport capacity. The results of this study highlight the effect of interchannel dynamics as well as the constraints of interaction between fluvial system and estuarine processes on sediment transport. Copyright © 2012 John Wiley & Sons, Ltd.
GROUNDWATER IN IRRIGATION SYSTEMS: FROM MENACE TO MAINSTAY
Authors: Bouarfa Sami , Kuper Marcel
Published: March 2012

Irrigation systems have changed significantly in the last 50 years. Originally supplied by surface water, its farming systems depend increasingly on the massive use of groundwater through private tubewells. Withdrawals are currently leading to a general decrease in groundwater table levels which in the past caused waterlogging due to excess surface irrigation. This new context calls for the repositioning of the paradigm of the twin menace of waterlogging and salinity in which the International Commission on Irrigation and Drainage (ICID) community defined its concepts. It also requires taking into consideration existing groundwater institutions, often informal and developed locally, more rarely legally recognized processes when moving towards groundwater governance. We present an analytical framework showing the role of these institutions in groundwater governance. This special issue contains a selection of papers presented at the 24th European Regional Conference of ICID in March 2011, organized by its French National Committee, AFEID. The selected contributions focus on critical analysis of formal and informal institutions at the local scale dealing with groundwater access, restoring the groundwater balance and water quality protection. We argue that these analyses can help building a more process‐oriented approach to policy and engineering, contributing to new modes of groundwater governance. Copyright © 2012 John Wiley & Sons, Ltd.
A high tender point count is associated with the presence of multiple idiopathic pain disorders: Results from a population study
Authors: Aggarwal V.R. , Macfarlane G.J. , McBeth J.
Published: March 2012

Background/aims

To test whether mechanical hyperalgesia is associated with multiple idiopathic pain disorders (IPDs) and whether this relationship is independent of the confounding effects of psychosocial factors.

Methods

One hundred eighteen subjects with chronic orofacial pain (COFP) were identified from their questionnaire responses to a population study in North West England. All subjects had a tender point examination according to the American College of Rheumatology classification. Validated tools on the questionnaire were used to identify presence of other IPDs (irritable bowel syndrome and chronic widespread pain) and psychosocial factors (anxiety, depression, health anxiety, sleep disturbance and reporting of somatic symptoms and adverse life events).

Results

Of the 118 subjects, 47.6% (n = 56) had COFP, 34.7% (n = 41) had COFP plus one IPD and 17.8% (n = 21) had all three IPDs. Univariate analysis revealed a dose‐response relationship between number of tender points (TPs) and number of IPDs [2–6 TPs (OR 2.6, 95% CI 1.0–7.3), ≥7 TPs (OR 10.5, 95% CI 3.8–29.3)] and number of IPDs and psychological distress [anxiety (OR 2.8, 95% CI 1.2–6.4), depression (OR 4.3, 95% CI 1.7–10.6), sleep disturbance (OR 4.8, 95% CI 1.6–14.6)]. The relationship between IPDs and TPs persisted after adjusting for psychosocial factors in multivariate analyses [2–6 TPs (OR 2.5, 95% CI 0.8–7.8) ≥7 TPs (OR 10.7, 95% CI 3.4–33.7)].

Conclusion

The dose‐response relationship between TPs and IPDs needs further investigation to determine the temporal nature of these relationships and to disentangle the complex gene–environment relationships that may influence the occurrence of multiple IPDs.
The Benefits and Challenges of Culturally Responsive EFL Critical Literature Circles
Authors: Fredricks Lori
Published: March 2012

Though some research has shown what applying a culturally relevant framework entails in an American context, and occasionally in an EFL setting, there is still too little research on how students respond to critical, culturally responsive pedagogy. More insight is needed into the specific challenges and benefits of critical approaches in diverse settings. As Tajikistani students are relatively new to a critical framework, they were introduced to a pluralistic way of analyzing texts through critical literature circles, allowing them to select readings and manage the direction of discussions. The study explored students’ reading experiences, habits, and attitudes. While these experiences were motivating, articulating personal and cultural associations with texts occasionally posed difficulties and revealed prejudices. Members became more confident readers and discovered life lessons in texts but struggled with emotionally charged issues such as discrimination and war. The article provides a detailed picture of participants’ challenges and experiences meant to inform other practitioners.
Reorganization of the DNA–nuclear matrix interactions in a 210 kb genomic region centered on c‐myc after DNA replication in vivo
Authors: Castillo‐Mora Rebeca C. , Aranda‐Anzaldo Armando
Published: March 2012

In the interphase nucleus of metazoan cells DNA is organized in supercoiled loops anchored to a nuclear matrix (NM). DNA loops are operationally classified in structural and facultative. Varied evidence indicates that DNA replication occurs in replication foci organized upon the NM and that structural DNA loops may correspond to the replicons in vivo. In normal rat liver the hepatocytes are arrested in G0 but synchronously re‐enter the cell cycle after partial‐hepatectomy leading to liver regeneration. Using this model we have previously determined that the DNA loops corresponding to a gene‐rich genomic region move in a sequential fashion towards the NM during replication and then return to their original configuration in newly quiescent cells, once liver regeneration has been achieved. In the present work we determined the organization into structural DNA loops of a gene‐poor region centered on c‐myc and tracked‐down its movement at the peak of S phase and after the return to cellular quiescence during and after liver regeneration. The results confirmed that looped DNA moves towards the NM during replication but in this case the configuration of the gene‐poor region into DNA loops becomes reorganized and after replication only the loop containing c‐myc resembles the original in the control G0 hepatocytes. Our results suggest that the local chromatin configuration around potentially active genes constraints the formation of specific structural DNA loops after DNA replication, while in non‐coding regions the structural DNA loops are only loosely determined after DNA replication by structural constraints that modulate the DNA–NM interactions. J. Cell. Biochem. 113: 2451–2463, 2012. © 2012 Wiley Periodicals, Inc.
Octanuclear Cu(I)‐dithiophosphates: An Efficient Catalyst System for N‐Arylation of Azoles, Amines, and Amides
Authors: Wu Cheng‐Chieh , Lee Bo‐Han , Liao Ping‐Kuei , Fang Ching‐Shiang , Liu C. W.
Published: March 2012

The formation of a C‐N bond via the cross‐couplings of aryl iodides with azoles, aryl amine, and amides can be successfully achieved in decent yield by the utilization of both [Cu 8(H){S2P(OiPr)2}6]+ and [Cu8{S2P(OEt)2}6]2+ as the pre‐catalysts.
The high‐mobility group A1‐estrogen receptor β nuclear interaction is impaired in human testicular seminomas
Authors: Esposito Francesco , Boscia Francesca , Gigantino Vincenzo , Tornincasa Mara , Fusco Alfredo , Franco Renato , Chieffi Paolo
Published: March 2012

It is well established that estrogens participate in the control of normal spermatogenesis and endogenous or environmental estrogens are involved in pathological germ cell proliferation including testicular germ cell tumors. The effects of estrogen are now known to be mediated by estrogen receptor‐α (ERα) and ERβ subtypes, but only ERβ has been found in human germ cells of normal testis. However, its expression was markedly diminished in human testicular seminomas. The expression and the possible interaction of ERβ and HMGA1 were studied in normal germ cells and in human testicular seminomas. GC1 and TCam‐2 germ cell lines, were used; in addition, a tissue micro‐array (TMA) was built using the most representative areas from 35 cases of human testicular seminomas. The expression and the interaction of ERβ and HMGA1 were observed by using immunoprecipitation and Western blot analyses in combination with immunocytochemistry and immunofluorescence analyses. Here, we show that ERβ interacts with HMGA1 in normal germ cells, while down regulation of ERβ associates with transcriptional co‐regulator HMGA1 over‐expression and cytoplasmic localization both in human testicular seminomas and in TCam‐2 cell line. In addition, we show that 17β‐oestradiol induces an HMGA1 increased cytoplasmic expression associated to an ERβ down‐regulation in TCam‐2 cell line. Taken together, our results suggest that exposure to estrogens or estrogen‐mimics, in some as of yet undefined manner, diminishes the ERβ‐mediated growth restraint in human testicular seminoma, probably due to the HMGA1 cytoplasmic delocalization associated with ERβ down‐regulation. J. Cell. Physiol. 227: 3749–3755, 2012. © 2012 Wiley Periodicals, Inc.
Abstracts of the 20th International Isotope Society (UK group) Symposium: Synthesis & Applications of Labelled Compounds 2011
Authors: Aigbirhio F. , Appleyard M. V. C. L. , Arrowsmith R. L. , Baldwin S. A. , Bayrakdarian M. , Botting N. P. , Cantin L. D. , Carbery D. R. , Carroll M. A. , Dixon L. I. , Dorff P. N. , Ellames G. , Elmore C. S. , Fishwick C. W. G. , Foot O. , Geach N. J. , Gowdy J. , Grainger R. S. , Gregson T. , Harker W. R. R. , Henderson P. J. F. , Heys J. R. , Homans S. W. , Hu Z. , Jackson S. , Johnston J. , Johnson P. , Kalverda A. , Kay C. , Kitson S. L. , Lanoue B. , Levitt M. H. , Li Y. , Lockley W. J. S. , Luo X , Ma P. , Middleton D. A. , Newsome J. , Pandya B. , Pascu S. I. , Patching S. G. , Phillips‐Jones M. K. , Powell M. E. , Riss P. , Simmons J. , Simpson T. M. , Smith A. D. , Thompson A. M. , Trembleau L. , Turtle R. , Watters K. W. , Zhang Q.
Published: March 2012

Meeting Summary

The 20th annual symposium of the International Isotope Society's United Kingdom Group took place at the Wellcome Genome Campus, Hinxton, Cambridge, UK on Tuesday 18 October 2011. The meeting was attended by around 70 delegates from academia and industry, the life sciences, chemical, radiochemical and scientific instrument suppliers.

Delegates were welcomed by Dr Ken Lawrie (GlaxoSmithKline, UK, chair of the IIS UK group). The subsequent scientific programme consisted of oral and poster presentations on isotopic chemistry and applications of labelled compounds or of chemistry with potential implications for isotopic synthesis. Both short‐lived and long‐lived isotopes were represented, as were stable isotopes. The symposium programme was divided into a morning session chaired by Prof. Chris Willis (University of Bristol, UK) and afternoon sessions chaired by Mr Mike Chappelle (Quotient Biosciences, UK) and by Dr Nick Bushby (AstraZeneca, UK). The UK meeting concluded with remarks from Dr Ken Lawrie (GlaxoSmithKline, Stevenage, UK).
177Lu‐labeled monomeric, dimeric and multimeric RGD peptides for the therapy of tumors expressing α(ν)β(3) integrins
Authors: Luna‐Gutiérrez Myrna , Ferro‐Flores Guillermina , Ocampo‐García Blanca , Jiménez‐Mancilla Nallely , Morales‐Avila Enrique , De León‐Rodríguez Luis , Isaac‐Olivé Keila
Published: March 2012

The conjugation of peptides to gold nanoparticles (AuNPs) produces biocompatible and stable multimeric systems with target‐specific molecular recognition. Peptides based on the cyclic Arg‐Gly‐Asp (RGD) sequence have been reported as high‐affinity agents for the α(ν)β(3) integrin. The aim of this research was to prepare a multimeric system of 177Lu‐labeled gold nanoparticles conjugated to c(RGDfK)C (cyclo(Arg‐Gly‐Asp‐Phe‐Lys)Cys) and to compare the radiation‐absorbed dose with that of 177Lu‐labeled monomeric and dimeric RGD peptides to α(ν)β(3) integrin‐positive U87MG tumors in mice. DOTA‐GGC (1,4,7,10‐tetraazacyclododecane‐N‐N′,N″,N‴‐tetraacetic acid‐Gly‐Gly‐Cys) and c(RGDfK)C peptides were synthesized and conjugated to AuNPs by a spontaneous reaction of the thiol groups. Transmission electron microscopy, ultraviolet–visible, X‐ray photoelectron spectroscopy, Raman and far‐infrared spectroscopy techniques demonstrated that AuNPs were functionalized with the peptides. For the 177Lu‐AuNP‐c(RGDfK)C to be obtained, the 177Lu‐DOTA‐GGC radiopeptide was first prepared and added to a solution of AuNPs followed by c(RGDfK)C (25 µl, 5 µ m) at 18 °C for 15 min. 177Lu‐DOTA‐GGC, 177Lu‐DOTA‐cRGDfK and 177Lu‐DOTA‐E‐c(RGDfK)2 were prepared by adding 177LuCl3 (370 MBq) to 5 µl (1 mg/ml) of the DOTA derivative diluted with 50 µl of 1  m acetate buffer pH 5. The mixture was incubated at 90 °C in a block heater for 30 min. Radiochemical purity was determined by ultrafiltration and HPLC analyses. Biokinetic studies were accomplished in athymic mice with U87MG‐induced tumors. The radiochemical purity for all 177Lu‐RGD derivatives was 96 ± 2%. 177Lu‐absorbed doses per injected activity delivered to U87MG tumors were 0.357 ± 0.052 Gy/MBq (multimer), 0.252 ± 0.027 Gy/MBq (dimer) and 0.102 ± 0.018 Gy/MBq (monomer). 177Lu‐labeled dimeric and multimeric RGD peptides demonstrated properties suitable for targeted radionuclide therapy of tumors expressing α(ν)β(3) integrins. Copyright © 2012 John Wiley & Sons, Ltd.
Interannual variability of moisture source over southern Indian Ocean during boreal summer and its relationship with local SST
Authors: Qiao Yunting , Wu Renguang , Huang Wei , Jian Maoqiu
Published: March 2012

In boreal summer, the southern Indian Ocean (SIO) features more evaporation than precipitation and thus it is a moisture source region for the Asian summer monsoon rainfall. In the present study, the interannual variability of moisture source over the SIO is analysed for boreal summer during 1979‐2008. The impacts of local sea surface temperature (SST) and the El Niño‐Southern Oscillation (ENSO) on the moisture source are compared and the possible mechanisms for the SST influence on the moisture source are investigated. The leading mode of the interannual variation of apparent moisture sink () over the SIO displays an obvious out‐of‐phase relationship over the western‐central SIO and the region to the northwest‐north of Australia. The interannual variations of < Q2> over the above two regions have significant positive correlation with local SST. An increase in local SST enhances convection and ascent, leading to more precipitation. Over the western‐central SIO, surface winds weaken corresponding to higher SST in the western‐central SIO and lower SST to the northwest‐north of Australia, leading to less oceanic evaporation. Thus, the variation of the moisture source over the western‐central SIO is contributed by both precipitation and evaporation. However, the variation of the moisture source to the northwest‐north of Australia is contributed mainly by precipitation. ENSO amplifies anomalous moisture source induced by local SST anomalies. ENSO and local SST work cooperatively to influence the moisture source over the SIO. Copyright © 2012 Royal Meteorological Society
Critical role of hyperthermic intraperitoneal chemoperfusion in the treatment of a patient with Pseudomyxoma peritonei
Authors: Cole Karin L. , Choudry Haroon A. , Jones Heather L. , Goodell Pamela P. , Bartlett David L.
Published: March 2012

The role of hyperthermic intraperitoneal chemoperfusion (HIPEC) in the treatment of Pseudomyxoma peritonei is debated by clinicians. We report the case of a patient who had multiple episodes of short‐interval disease recurrence following debulking surgery, and only achieved long‐term remission with the addition of HIPEC. A review of the relevant literature is presented. J. Surg. Oncol. 2012; 106:513–516. © 2012 Wiley Periodicals, Inc.
Demography of greater prairie‐chickens: Regional variation in vital rates, sensitivity values, and population dynamics
Authors: McNew Lance B. , Gregory Andrew J. , Wisely Samantha M. , Sandercock Brett K.
Published: March 2012

Intensification of rangeland management has coincided with population declines among obligate grassland species in the largest remaining tallgrass prairie in North America, although causes of declines remain unknown. We modeled population dynamics and conducted sensitivity analyses from demographic data collected for an obligate grassland bird that is an indicator species for tallgrass prairie, the greater prairie‐chicken (Tympanuchus cupido), during a 4‐year study in east‐central Kansas, USA. We examined components of reproductive effort and success, juvenile survival, and annual adult female survival for 3 populations of prairie‐chickens across an ecological gradient of human landscape alteration and land use. We observed regional differences in reproductive performance, survivorship, and population dynamics. All 3 populations of prairie‐chickens were projected to decline steeply given observed vital rates, but rates of decline differed across a gradient of landscape alteration, with the greatest declines in fragmented landscapes. Elasticity values, variance‐scaled sensitivities, and contribution values from a random‐effects life‐table response experiment all showed that the finite rate of population change was more sensitive to changes in adult survival than other demographic parameters in our declining populations. The rate of population change was also sensitive to nest survival at the most fragmented and least intensively grazed study site; suggesting that patterns of landscape fragmentation and land use may be affecting the relative influences of underlying vital rates on rates of population growth. Our model results indicate that 1) populations of prairie‐chickens in eastern Kansas are unlikely to be viable without gains from immigration, 2) rates of population decline vary among areas under different land management practices, 3) human land‐use patterns may affect the relative influences of vital rates on population trajectories, and 4) anthropogenic effects on population demography may influence the regional life‐history strategies of a short‐lived game bird. © 2012 The Wildlife Society.
Peroxidase‐catalyzed electrochemical assay of hydrogen peroxide: A ping–pong mechanism
Authors: Deyhimi F. , Nami F.
Published: March 2012

In view of the great importance of determination of hydrogen peroxide in many scientific fields and industrial applications and the attractive operational simplicity of potentiometric approach for the enzymatic assay, the kinetics of horseradish peroxidase–catalyzed electrochemical assay of H2O2 was studied in this work at 25°C. All kinetic characteristics were determined by the double reciprocal Lineweaver–Burk and (primary and secondary) double reciprocal Hanes–Woolf plots. The results confirmed that the reaction follows a ping–pong mechanism. The Michaelis–Menten constants for H2O2 and 4‐fluorophenol were Km = 0.081 ± 0.001 mM and K4‐FPm = 0.185 ± 0.002 mM, respectively. The maximum rate was also estimated to be Vmax  = 0.182 ± 0.002 mM min−1 (at 25 ± 0.05°C). © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 699–704, 2012
Kinetic studies of glucose electrocatalytic oxidation on GC/Ni electrode
Authors: Danaee I. , Jafarian M. , Forouzandeh F. , Gobal F.
Published: March 2012

Nickel‐modified glassy carbon electrode (GC/Ni) prepared by galvanostatic deposition was used for the electrocatalytic oxidation of glucose in alkaline solutions where different electrochemical methods were employed. In cyclic voltammetry studies, in the presence of glucose an increase in the peak current of the oxidation of nickel hydroxide is followed by a decrease in the corresponding cathodic current. This suggests that the oxidation of glucose is being catalyzed through mediated electron transfer across the nickel hydroxide layer comprising nickel ions of various valence states. Under the chronoamperometric regime, the reaction followed a Cottrellian behavior and the diffusion coefficient of glucose was found to be 8 × 10−6 cm2 s−1. A mechanism based on the electrochemical generation of Ni3+‐active sites and their subsequent consumptions by glucose has been discussed, and kinetic parameters have been derived. The heterogeneous rate constants for the oxidation of glucose at the surface of modified electrodes were determined by rotating disk electrode using the Koutecky–Levich plots, which are in agreement with the data obtained by chronoamperometry. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 712–721, 2012
Modeling of Network Formation in Nitroxide‐Mediated Radical Copolymerization of Vinyl/Divinyl Monomers Using a Multifunctional Polymer Molecule Approach
Authors: Hernández‐Ortiz Julio C. , Vivaldo‐Lima Eduardo , Penlidis Alexander
Published: March 2012

A mathematical model for the kinetics of copolymerization with crosslinking of vinyl/divinyl monomers in the presence of stable nitroxyl radicals is presented. A reaction scheme considering multifunctional polymer molecules is proposed. The Flory‐Stockmayer theory is used for the post‐gelation period. Average crosslink and cyclization densities are calculated using two different approaches. Good agreement between predicted profiles and experimental data from our and other groups is observed in all cases. Overall monomer concentration, controller/initiator ratio, and crosslinker initial concentration are found to be the governing factors for the development of average crosslink and cyclization densities and therefore for the homogeneity of the resulting polymer network.

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Cytoprotective effects of hesperetin and hesperidin against amyloid β‐induced impairment of glucose transport through downregulation of neuronal autophagy
Authors: Huang Shang‐Ming , Tsai Shin‐Yi , Lin Jer‐An , Wu Chi‐Hao , Yen Gow‐Chin
Published: March 2012

Scope

This study investigated whether flavonoids, such as hesperetin and hesperidin, inhibited amyloid β (Aβ)‐impaired glucose utilization through regulating cellular autophagy in insulin‐stimulated neuronal cells.

Methods and results

In this study, we used a toxic Aβ1‐42 peptide to impair insulin‐stimulated glucose utilization in Neuro‐2A cells, and this study also hypothesized that Aβ‐induced autophagy might be emerging as a key process regulating neuronal glucose uptake. Additionally, hesperetin and hesperidin were used to test the neuroprotective effect against Aβ‐induced impairment of glucose utilization. Our data found that Aβ‐stimulated autophagy activation promoted the phenomenon of impairment of neuronal energy metabolism, including glucose uptake, glucose transporters (GLUTs), and insulin signaling cascades. In this study, confocal images of autophagy punctate further confirmed that downregulation of Aβ‐stimulated autophagy could increase insulin‐stimulated neuronal glucose uptake. Moreover, treatment with hesperetin and hesperidin improved Aβ‐impaired glucose utilization by inhibiting Aβ‐induced autophagy in neuronal cells.

Conclusion

These findings suggest that downregulation of autophagy may be one of the approaches to control the impairment of energy metabolism leading to neuronal injury in the early development of Alzheimer's disease, and hesperetin or hesperidin may be a potential agent in the preventing of Alzheimer's disease progression.