bluuebunny/crossref_metadata_2025 huggingface dataset:
The Most Frequently Used English Phrasal Verbs in American and British English: A Multicorpus Examination
Authors: LIU DILIN
Published: December 2011

This study uses the Corpus of Contemporary American English and the British National Corpus as data and Biber, Johansson, Leech, Conrad, and Finegan's (1999) and Gardner and Davies' (2007) informative studies as a starting point and reference. The study offers a cross‐English variety and cross‐register examination of the use of English phrasal verbs (PVs), one of the most difficult aspects of English for learners of English as a foreign language or English as a second language. The study first identified the frequency and usage patterns of the most common PVs in the two corpora and then analyzed the results using statistical procedures, the chi‐square and dispersion tests, to determine any significant cross‐variety or ‐register differences. Besides validating many of the findings of the two previous studies (although neither was a cross‐English variety examination), the results of this study provide new, useful information about the use of PVs. In addition, the study resulted in a comprehensive list of the most common PVs in American and British English, one that complements those offered by the two previous studies with more necessary items and more detailed usage information. The study also presents a cross‐register list of the most frequent PVs, showing in which register(s) each of the PVs is primarily used. Finally, pedagogical and research implications are discussed.
Course‐Taking Patterns of Latino ESL Students: Mobility and Mainstreaming in Urban Community Colleges in the United States
Authors: RAZFAR ARIA , SIMON JENNY
Published: December 2011

In most Western countries where English is the medium of instruction, there is a substantial gap in student success between immigrant English as a second language (ESL) students and non‐ESL students. In the United States, this situation has been observed in particular with Latino ESL students. This article describes a longitudinal study of two cohorts of Latino ESL students and compares the success of students who mainstreamed into college‐level content courses and those who did not. More specifically, drawing on quantitative transcript analysis and focus group discussions, this study examines several factors impacting the mobility of Latino ESL students in a large urban community college district in the United States. The qualitative analysis focused on several themes including challenges to navigating the curriculum, the significant role of ESL in providing opportunities to use English, and the supportive role of instructors. The quantitative analysis focused on mainstreaming, enrollment patterns, and success measures, including grade point average (GPA) and course‐completion ratio. The findings suggest that students who mainstream earlier or concurrently enroll in content level courses are more successful in terms of course completion and GPA. Implications of the study are discussed in relation to placement, instruction, and further areas of research. Although the ESL programs and the linguistic‐minority population of this study are located in the United States, the issues raised and lessons learned can enrich the broader international conversation surrounding language minority education.
Observations of in-situ generated gravity waves during a stratospheric temperature enhancement (STE) event
Authors: Gerrard A. J. , Bhattacharya Y. , Thayer J. P.
Published: December 2011

Abstract. Evidence for in situ generated atmospheric gravity waves associated with a stratospheric temperature enhancement (STE) are presented. The signatures of two sets of gravity waves are observed by molecular-aerosol lidar in conjunction with the early December 2000 STE event above Sondrestrom, Greenland. The first set of gravity waves shows downward phase progression with a vertical wavelength of ~8 km while the second set shows upward phase progression with a vertical wavelength of ~9 km. With estimates of the background wind fields from synoptic analyses, the various intrinsic gravity wave parameters of these two wave structures are found. The observed wave features compare well to previous numerical modeling predictions.
A global compilation of over 13 000 dissolved iron measurements: focus on distributions and processes in the Southern Ocean
Authors: Tagliabue A. , Mtshali T. , Aumont O. , Bowie A. R. , Klunder M. B. , Roychoudhury A. N. , Swart S.
Published: December 2011

Abstract. Due to its importance as a limiting nutrient for phytoplankton growth in large regions of the world's oceans, ocean water column observations of concentration of the trace-metal iron (Fe) have increased markedly over recent decades. Here we compile > 13 000 global measurements of dissolved Fe (dFe) and make this available to the community. We then conduct a synthesis study focussed on the Southern Ocean, where dFe plays a fundamental role in governing the carbon cycle, using four regions, six basins and five depth intervals as a framework. Our analysis reveals the importance of biological activity and dFe inputs in governing the inter-region and inter-basin differences in surface dFe, respectively. In deep waters, the major controls of inter-region and inter-basin dFe variability are ligand distributions and deep dFe inputs or water mass characteristics, respectively. We find that even in regions where many dFe measurements exist, the processes governing the seasonal evolution of dFe remain enigmatic, suggesting that, aside from broad sub-Antarctic-Antarctic trends, biological activity might not the major driver of dFe variability. Nevertheless, missing measurements during key seasonal transitions make it difficult to better quantify and understand surface water replenishment processes and the seasonal Fe cycle. Statistical differences exist in the measured dFe between measurements taken over the period 1989–2002 and 2003–2008, which may reflect progress in clean sampling and analysis techniques. Finally, we detail the degree of seasonal coverage by region, basin and depth. By synthesising prior measurements we suggest a role for different processes and highlight key gaps in understanding, which we hope can help structure future research efforts in the Southern Ocean.
Quantitative analysis on the ecological impact of large-scale water transfer project on water resource area in a changing environment
Authors: Yan D. H. , Wang H. , Li H. H. , Wang G. , Qin T. L. , Wang D. Y. , Wang L. H.
Published: December 2011

Abstract. The interbasin long-distance water transfer project is a key support for the reasonable allocation of water resources in a large-scale area, which can optimize the spatiotemporal change of water resources to reinforce the guarantee of the access of water resources. And large-scale water transfer projects have a deep influence on ecosystems; besides, global climate change causes the uncertainty and additive effect of the ecological impact of water transfer projects. Therefore, how to assess the ecological and environmental impact of large-scale water transfer projects in both construction and operation has triggered a lot of attention. The water-output area of the western route of China's South-North Water Transfer Project was taken as the study area of the present article. According to relevant evaluation principles and on the basis of background analysis on the eco-environment of the study area, the influence factors were identified and evaluation indexes were established. The climate-hydrology-ecology coupled simulation model was used to imitate the laws of ecological and environmental change of the water resource area in a changing climate. The emphasis of influence analysis and quantitative evaluation was placed on the reservoir construction and operation scheduling, representative river corridors and wetlands, natural reserves and the water environment of river basins below the dam sites. In the end, an overall influence evaluation of the impact of the project on the water circulation and ecological evolution of the water resource area was conducted. The research results were as follows: the environmental impacts of the western route project in the water resource area were concentrated on two aspects, i.e. the permanent destruction of vegetation during the phase of dam construction and river impoundment, and the significant influence on the hydrological situation of natural river corridor after the implementation of water transfer. Its impact on local climate, vegetation ecology, typical wetlands, natural reserves and the water environment of river basins below the dam sites was small.
Albedo of the ice-covered Weddell and Bellingshausen Sea
Authors: Weiss A. I. , King J. C. , Lachlan-Cope T. A. , Ladkin R. S.
Published: December 2011

Abstract. This study investigates the surface albedo of the sea ice areas adjacent to the Antarctic Peninsula during the austral summer. Aircraft measurements of the surface albedo which were conducted in the sea ice areas of the Weddell and Bellingshausen Sea show significant differences between these two regions. The averaged surface albedo varied between 0.13 and 0.81. The ice cover of the Bellingshausen Sea consisted mainly of first year ice and the sea surface showed an averaged sea ice albedo of αi = 0.64 ± 0.2 (± standard deviation). The mean sea ice albedo of the pack ice area in the Western Weddell Sea was αi = 0.75 ± 0.05. In the Southern Weddell Sea, where new, young sea ice prevailed, a mean albedo value of αi = 0.38 ± 0.08 was observed. Relatively warm open water and thin, newly formed ice had the lowest albedo values, whereas relatively cold and snow-covered pack ice had the highest albedo values. All sea ice areas consist of a mixture of a large variability of different sea ice types. An investigation of commonly used parameterizations of albedo as a function of surface temperature in the Weddell and Bellingshausen Sea ice areas showed that the albedo parameterizations don't work well in particular for areas with new, young ice. We determined typical linear temperature-albedo functions for three sea ice areas adjacent to the Antarctic Peninsula, which are reflecting the differences in the mixture of ice age, thickness and sea ice surface cover.
The Romanian Legionary Movement: An Orthodox Christian Assessment of Anti-Semitism
Authors: Webster Alexander F. C.
Published: December 2011

The Legionary Movement in Romania between the two world wars in this century provides a useful historico-ethical case study of the inter-relations among anti-Semitism, modern nationalism, and Eastern Orthodox Christianity. To be sure, this historical phenomenon is fascinating in its own right, and the burgeoning literature on this subject reflects the interests of historians and social scientists alike. The purpose of this essay, however, is to examine this complex political-cultural movement in the light of the secondary literature and the primary documentary source in order to evaluate it from the perspective of an Orthodox Christian moral theologian.
The Soviet Union and the Carter Administration
Authors: Freedman Robert O.
Published: December 2011

lt has now been almost six years since Jimmy Carter left office. In this period, the memoirs of almost everyone of the key American participants in Soviet-American relations during the Carter Administration have been published, along with evaluations by Soviet officials, and a major Soviet defector. In addition a number of American scholars have published analyses of the Carter Administration's dealing with the USSR. the most extensive being that of Raymond Garthoff, himself a participantobserver of Soviet American relations during this period.
The Bolshevik Sowing Committees of 1920: Apotheosis of War Communism?
Authors: Lih Lars T.
Published: December 2011

In December 1920, on the eve of the introduction of the New Economic Policy (NEP), the Bolsheviks embarked on a crash campaign to avert an agricultural crisis. The Eighth Congress of Soviets passed legislation known by the name of one of its principal innovations, the sowing committees (posevkomy). The usual view of this legislation is that it was a last binge of revolutionary inebriation before the sobering morning after of NEP -a desperate attempt to use civil-war methods to undo the damage done by civil-war methods. The full record of the legislation and the debate surrounding it tell a different story.
The Soviet Miners' Strike, July 1989: Perestroika from Below
Authors: Friedgut Theodore H. , Siegelbaum Lewis H.
Published: December 2011

The editors are very pleased to publish Theodore H. Friedgut's and Lewis H. Siegelbaum's fascinating study of the July 1989 miners strike. Not only is their account the most complete analysis in print, but the circumstances that led to their being in Donetsk in August 1989 began here in Pittsburgh.
Circulating Anti-PLAC1 Antibodies during Pregnancy and in Women with Reproductive Failure: A Preliminary Analysis
Authors: Kotto-Kome Anne C. , Silva Celso , Whiteman Valerie , Kong Xiaoyuan , Fant Michael E.
Published: December 2011

The aims of this study were to determine the prevalence of anti-PLAC1 antibodies in normal pregnant women and in women with infertility or recurrent pregnancy loss (RPL). Secondary outcomes were the development of complications associated with anti-PLAC1 seropositivity and the rate of seroconversion during pregnancy. Sera from 103 healthy pregnant women and 45 women with unexplained infertility or RPL were analyzed by ELISA. The prevalence of anti-PLAC1 antibodies was 2% in healthy pregnant women and 4.5% in women with unexplained infertility or RPL (P=0.355). There was no detectable association of seropositivity with increased risk of pregnancy complications. Finally, 2% of women seroconverted during pregnancy. The prevalence of anti-PLAC1 antibodies in women with unexplained infertility or RPL is not significantly higher than the prevalence in normal pregnant women. However, the sample size in this study was too small. The exposure to the PLAC1 antigen during pregnancy can lead to the spontaneous development of antibodies.
Auf dem Weg zur automatisierten Oligosaccharid‐ Synthese
Authors: Hsu Che‐Hsiung , Hung Shang‐Cheng , Wu Chung‐Yi , Wong Chi‐Huey
Published: December 2011

Kohlenhydrate spielen eine wichtige Rolle bei biologischen Vorgängen. Das Fortschrittstempo der Kohlenhydratforschung ist jedoch relativ langsam, was unter anderem mit der Komplexität der Kohlenhydratstrukturen und dem Fehlen allgemein anwendbarer Synthesemethoden und Verfahren zur Untersuchung dieser Klasse von Biomolekülen zusammenhängt. Jüngste Fortschritte in der Synthese haben ergeben, dass viele dieser Probleme umgangen werden können. In diesem Aufsatz beschreiben wir die Methoden, die entwickelt wurden, um mit den Herausforderungen kohlenhydratvermittelter biologischer Vorgänge umzugehen. Besonderes Augenmerk wird dabei auf die Entwicklung der automatisierten Synthese von Oligosacchariden gerichtet. Darüber hinaus werden auch Kohlenhydrat‐Mikroarrays und Impfstoffe auf Kohlenhydratbasis behandelt.
Preparation and characterization of high‐molecular‐weight poly(l‐lactic acid) by chain‐extending reaction with phosphites
Authors: Xie Ji‐Xing , Yang Rong‐Jie
Published: December 2011

Poly(l‐lactic acid) (PLLA) of high molecular weight was prepared by a chain‐extending reaction in a microcompounder. Phosphites were used as chain extenders to increase the molecular weight of the PLLA prepolymer, which was prepared by the bulk polycondensation of l‐lactic acid. The effects of the amount of phosphite, the temperature, and the screw speed on the torque of the PLLA melt were studied. Under the optimal conditions, the molecular weight of PLLA increased from 62,100 to 126,000 g/mol. The chemical structure and crystallinity of PLLA were characterized by Fourier transform infrared spectroscopy, 1H‐NMR and 13C‐NMR, differential scanning calorimetry, and X‐ray diffraction. The mechanical properties of PLLA were measured. The results indicate that triphenyl phosphite (TPPi) was an effective chain extender for PLLA. The role of the TPPi in chain extending is suggested to be an esterification‐promotion agent. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Kinetics and mechanism of the charge‐transfer polymerization of methyl methacrylate initiated with n‐butyl amine and carbon tetrachloride catalyzed by palladium dichloride
Authors: Tiwari Rajesh , Spivak David A.
Published: December 2011

We studied the kinetics and mechanism of the charge‐transfer polymerization of methyl methacrylate (MMA) initiated with n‐butyl amine (BA) and carbon tetrachloride (CCl4) catalyzed by palladium dichloride (PdCl2 or PdII) in a dimethyl sulfoxide medium by using a dilatometric technique at 60°C. The rate of polymerization (Rp) was a function of [MMA], [BA], [CCl4], and [PdII]. The kinetic data indicated a mechanism involving the possible participation of the charge‐transfer complex formed between the {BA–PdII} complex and CCl4 or monomer in the polymerization of MMA. In the absence of either CCl4 or BA, no polymerization of MMA was observed under these experimental conditions. Rp was inhibited by hydroquinone; this suggested a free‐radical initiation. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Morphological, infrared, and ionic conductivity studies of poly(ethylene oxide)–49% poly(methyl methacrylate) grafted natural rubber–lithium perchlorate salt based solid polymer electrolytes
Authors: Ahmad A. , Rahman M. Y. A. , Su′ait M. S.
Published: December 2011

The potential of poly(ethylene oxide) (PEO) and 49% poly(methyl methacrylate) grafted natural rubber (MG49) as a polymer host in solid polymer electrolytes (SPE) was explored for electrochemical applications. PEO–MG49 SPEs with various weight percentages of lithium perchlorate salt (LiClO4) was prepared with the solution casting technique. Characterization by scanning electron microscopy, Fourier transform infrared spectroscopy, and impedance spectroscopy was done to investigate the effect of LiClO4 on the morphological properties, chemical interaction, and ionic conductivity behavior of PEO–MG49. Scanning electron microscopy analysis showed that the surface morphology of the sample underwent a change from rough to smooth with the addition of lithium salts. Infrared analysis showed that the interaction occurred in the polymer host between the oxygen atom from the ether group (COC) and the Li+ cation from doping salts. The ionic conductivity value increased with the addition of salts because of the increase in charge carrier up to the optimum value. The highest ionic conductivity obtained was 8.0 × 10−6 S/cm at 15 wt % LiClO4. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Biodegradable poly(butylene succinate‐co‐butylene adipate)/multiwalled carbon nanotube nanocomposites: Preparation, morphology, and crystallization behavior
Authors: Zhu Siyu , Zhao Yuanyuan , Qiu Zhaobin
Published: December 2011

Biodegradable poly(butylene succinate‐co‐butylene adipate) (PBSA)/multiwalled carbon nanotubes (MWCNTs) nanocomposites were prepared via a simple melt‐compounding method at low MWCNTs contents. Scanning and transmission electron microscopy observations revealed a relatively nice dispersion of MWCNTs throughout the PBSA matrix. Both the nonisothermal and isothermal melt crystallizations of PBSA were enhanced significantly in the nanocomposites relative to neat PBSA because of the presence of MWCNTs; however, the crystal structure of PBSA remained unchanged. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
A Diverted Total Synthesis of Mycolactone Analogues: An Insight into Buruli Ulcer Toxins
Authors: Chany Anne‐Caroline , Casarotto Virginie , Schmitt Marjorie , Tarnus Céline , Guenin‐Macé Laure , Demangel Caroline , Mirguet Olivier , Eustache Jacques , Blanchard Nicolas
Published: December 2011

Mycolactones are complex macrolides responsible for a severe necrotizing skin disease called Buruli ulcer. Deciphering their functional interactions is of fundamental importance for the understanding, and ultimately, the control of this devastating mycobacterial infection. We report herein a diverted total synthesis approach of mycolactones analogues and provide the first insights into their structure–activity relationship based on cytopathic assays on L929 fibroblasts. The lowest concentration inducing a cytopathic effect was determined for selected analogues, allowing a clear picture to emerge by comparison with the natural toxins.
Covalent and Noncovalent Immobilization of Arylid‐BOX Ligands and Their Derivatives: Evaluation in the Catalytic Asymmetric Cyclopropanation of Styrenes
Authors: Carreiro Elisabete P. , Moura Nuno M. M. , Burke Anthony J.
Published: December 2011

The aim of this work was to immobilize an Arylid‐BOX ligand on solid supports either by covalent attachment (to Wang resin) or by noncovalent attachment (on MK10 and SiO2) and to evaluate the products in the catalytic asymmetric cyclopropanation (CACP) of styrene in the presence of CuI and CuII. The synthetic strategy used to obtain the target functionalized Arylid‐BOX furnished a new, partially hydrogenated, Arylid‐BOX derivative. Evaluation of this ligand in the catalytic asymmetric cyclopropanation of styrene in the presence of CuI gave a highest ee of 68 %, a result better than that obtained for the nonhydrogenated Arylid‐BOX ligand. The new ligand was grafted to Wang resin; a loading of 0.321 mmol of ligand per gram of polymer could be obtained. [Cu(CH3CN)4]PF6 or Cu(OTf)2 were used in the CACP of styrene with CH2Cl2 or toluene as solvents. A highest ee of 71 % was obtained and the catalyst could be recycled and reused up to four times. In the case of the heterogeneous CACP in the presence of [Cu(CH3CN)4]PF6 and toluene, the yields, ees, des, and selectivities were maintained over the four cycles. This heterogeneous catalyst was shown to be very similar to the homogeneous catalyst with regard to selectivity and activity. In the case of noncovalent immobilization, both CuI and CuII Arylid‐BOX complexes were immobilized on Montmorillonite K10 (MK10) and silica gel through noncovalent interactions. The obtained results depended on the natures both of the chiral ligand and of the support. In the case of MK10, enantioselectivities of 62 % ee (trans‐cyclopropane) and 65 % ee (cis‐cyclopropane) could be achieved, whereas in the case of the silica‐gel‐supported catalyst, enantioselectivities of 50 % ee (trans‐cyclopropane) and 43 % ee (cis‐cyclopropane) were obtained.
Dealing with high dimensionality for the identification of common and rare variants as main effects and for gene‐environment interaction
Authors: Bickeböller Heike , Houwing‐Duistermaat Jeanine J. , Wang Xuefeng , Yan Xiting
Published: December 2011

In addition to genome‐wide association studies, sequence data are now up and coming, increasing the need for even more effective methods of dealing with high dimensionality and the identification of variants beyond common variant main effects. The contributors to Genetic Analysis Workshop 17 Group 4 applied novel and recently proposed methods for handling population structure, high dimensionality, and gene‐environment interactions in the context of mini‐exome sequence data. For the collapsing of rare variants into gene summaries, some of the contributions considered the computationally fast, straightforward summing of all or particular subsets of rare variants. Other methods were comparatively time‐consuming and complex but offered a data‐driven approach, such as reduction in the subset of rare variants to be considered using a U statistic and semiparametric modeling of single‐nucleotide polymorphism effects implementing kernel machines. Several approaches were applied using regression models, regularized regression, and kernels. Testing for gene‐specific main effects and gene‐environment interaction using least‐squares kernel machines showed more flexibility and was supervised compared with a two‐step approach that used a random effects model that incorporated an empirical Bayes estimate. However, the random effects model was the only method capable of treating family data, at least in their present form. Genet. Epidemiol. 35:S35–S40, 2011. © 2011 Wiley Periodicals, Inc.
Peripheral low intensity sign in hepatic hemangioma: Diagnostic pitfall in hepatobiliary phase of Gd‐EOB‐DTPA‐enhanced MRI of the liver
Authors: Tamada Tsutomu , Ito Katsuyoshi , Ueki Ai , Kanki Akihiko , Higaki Atsushi , Higashi Hiroki , Yamamoto Akira
Published: December 2011

Purpose:

To describe the presence of “peripheral low intensity sign” in hepatic hemangioma in the hepatobiliary phase (HP) of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA)‐enhanced magnetic resonance imaging (MRI) and to compare the frequency of this sign between hepatic hemangiomas and hepatic metastases.

Materials and Methods:

The Institutional Review Board approved this study and waived the requirement for informed consent. Sixty‐four patients with 51 hepatic hemangiomas (n = 31 patients) and with 58 hepatic metastases (n = 33 patients) underwent Gd‐EOB‐DTPA‐enhanced MRI. In all hepatic hemangiomas, 41 lesions were the typical type and 10 were the high flow type. HP images were qualitatively evaluated for the frequency of peripheral low intensity sign in hepatic hemangiomas and hepatic metastases using a four‐point scale. Statistical evaluations were performed with a Mann–Whitney U‐test.

Results:

Peripheral low intensity signs were demonstrated in 24 (47%) of 51 hepatic hemangiomas, while they were seen in 27 (47%) of 58 hepatic metastases. There was no significant difference in the mean visual score of peripheral low intensity sign between all hepatic hemangiomas (0.84 ± 1.03) and hepatic metastases (0.76 ± 0.92). The mean visual score of peripheral low intensity sign in typical hemangiomas (1.02 ± 1.06) was significantly higher than that in high flow hemangiomas (0.10 ± 0.32) (P = 0.008).

Conclusion:

Peripheral low intensity sign is not specific for malignant tumors, and can be seen even in hepatic hemangiomas on HP of Gd‐EOB‐DTPA‐enhanced MRI. J. Magn. Reson. Imaging 2012;35:852–858. © 2011 Wiley Periodicals, Inc.
Mid‐term evaluation of the effects of dynamic neutralization system on lumbar intervertebral discs using quantitative molecular MR imaging
Authors: Ciavarro Cristina , Caiani Enrico G. , Brayda‐Bruno Marco , Zerbi Alberto , Galbusera Fabio , Vaga Stefania , Lamartina Claudio
Published: December 2011

Purpose:

To evaluate the mid‐term effects of implant of dynamic neutralization system (Dynesys) on disc tissue in patients with lumbar discopathy, through the quantification of glycosaminoglycans (GAG) concentration, both in treated and adjacent levels, by analysis of delayed gadolinium‐enhanced MRI contrast (dGEMRIC) images.

Materials and Methods:

Ten patients with low back pain underwent the dGEMRIC diagnostic protocol before, 6‐months and after 2 years from surgery. Each patient was also evaluated with visual analog (VAS), Oswestry, and Prolo scales both at presurgery and during follow‐up. From dGEMRIC images, a ΔT1 parametric map was obtained for each disc, as quantitative indicator of its GAG concentration, and divided in 13 sectors, which were classified at presurgery as normal or abnormal, based on a 70‐ms threshold. Evolution of ΔT1 was studied during the follow‐up.

Results:

Nine of ten patients completed the follow‐up. VAS, Oswestry, and Prolo grades showed an improvement. This was accompanied by a reduction of ΔT1 in abnormal segments while normal segments showed a pattern of initial worsening at 6 months, followed by an improvement after 2 years.

Conclusion:

Our study confirmed the improvement in clinical evaluation, and for the first time related this to the changes in discs GAG concentration. J. Magn. Reson. Imaging 2012;35:1145‐1151. © 2011 Wiley Periodicals, Inc.
Improving SNR and B1 transmit field for an endorectal coil in 7 T MRI and MRS of prostate cancer
Authors: Arteaga de Castro C. S. , van den Bergen B. , Luijten P. R. , van der Heide U. A. , van Vulpen M. , Klomp D. W. J.
Published: December 2011

Higher magnetic field strengths like 7 T and above are desirable for MR spectroscopy given the increased spectral resolution and signal to noise ratio. At these field strengths, substantial nonuniformities in B1+/− and radiofrequency power deposition become apparent. In this investigation, we propose an improvement on a conventionally used endorectal coil, through the addition of a second element (stripline). Both elements are used as transceivers. In the center of the prostate, approximately 40% signal to noise ratio increase is achieved. In fact, the signal to noise ratio gain obtained with the quadrature configuration locally can be even greater than 40% when compared to the single loop configuration. This is due to the natural asymmetry of the B1+/− fields at high frequencies, which causes destructive and constructive interference patterns. Global specific absorption rate is reduced by almost a factor of 2 as expected. Furthermore, approximately a 4‐fold decrease in local specific absorption rate is observed when normalized to the B1 values in the center of the prostate. Because of the 4‐fold local specific absorption rate decrease obtained with the dual channel setup for the same reference B1 value (20 μT at 3.5 cm depth into the prostate) as compared to the single loop, the transmission power B1 duty cycle can be increased by a factor 4. Consequently, when using the two‐element endorectal coil, the radiofrequency power deposition is significantly reduced and radiofrequency intense sequences with adiabatic pulses can be safely applied at 7 T for 1H magnetic resonance spectroscopy and MRI in the prostate. Altogether, in vivo 1H magnetic resonance spectroscopic imaging of prostate cancer with a fully adiabatic sequence operated at a minimum B1+ of 20 μT shows insensitivity to the nonuniform transmit field, while remaining within local specific absorption rate guidelines of 10 W/kg. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Overexpression of the VSSC‐associated CAM, beta‐2, enhances LNCaP cell metastasis associated behavior
Authors: Jansson Keith H. , Lynch Jill E. , Lepori‐Bui Nadia , Czymmek Kirk J. , Duncan Randall L. , Sikes Robert A.
Published: December 2011

BACKGROUND

Prostate cancer (PCa) is the second‐leading cause of cancer death in American men. This is due largely to the “silent” nature of the disease until it has progressed to a highly metastatic and castrate resistant state. Voltage sensitive sodium channels (VSSCs) are multimeric transmembrane protein complexes comprised of a pore‐forming α subunit and one or two β subunits. The β‐subunits modulate surface expression and gating kinetics of the channels but also have inherent cell adhesion molecule (CAM) functions. We hypothesize that PCa cells use VSSC β‐subunits as CAMs during PCa progression and metastasis.

METHODS

We overexpressed the beta‐2 isoform as a C‐terminal fusion protein with enhanced cyan fluorescence protein (ECFP) in the weakly metastatic LNCaP cells. The effect of beta‐2 overexpression on cell morphology was examined using confocal microscopy while metastasis‐associated behavior was tested by performing several in vitro metastatic functional assays and in vivo subcutaneous tumor studies.

RESULTS

We found that cells overexpressing beta‐2 (2BECFP) converted to a bipolar fibroblastic morphology. 2BECFP cells were more adhesive than control (ECFP) to vitronectin (twofold) and Matrigel® (1.3‐fold), more invasive through Matrigel® (3.6‐fold in 72 hr), and had enhanced migration (2.1‐fold in 96 hr) independent of proliferation in wound‐healing assays. In contrast, 2BECFP cells have a reduced tumor‐take and tumor volume in vivo even though the overexpression of beta‐2 was maintained.

CONCLUSIONS

Functional overexpression of VSSC β‐subunits in PCa may be one mechanism leading to increased metastatic behavior while decreasing the ability to form localized tumor masses. Prostate 72:1080–1092, 2012. © 2011 Wiley Periodicals, Inc.
A review of risk measures in pharmacoepidemiology with tips for statisticians in the pharmaceutical industry
Authors: Quartey George , Wang Jixian , Kim Joseph
Published: December 2011

Pharmacoepidemiology is the study of the therapeutic effects, risk, and use of drugs in large populations, which applies epidemiological methods and reasoning. As reflected in the recent strengthening of the pharmacovigilance legislation in Europe, greater attention has been placed to epidemiological research in response to an increasing call by the public for further post‐marketing studies on the safety and efficacy of drugs. Various measures of risk are used in pharmacoepidemiology to quantify the probability of experiencing an adverse outcome and capture the relative increases in risk between treated and untreated populations: cumulative incidence, incidence rate, absolute risk reduction, relative risk, odds ratio, incidence rate ratio, and time to event outcomes. We review in this paper the commonly used measures of risk in pharmacoepidemiology and provide some practical tips for the industry statistician. Copyright © 2011 John Wiley & Sons, Ltd.
Universal but not truly ‘global’: governmentality, economic liberalism, and the international
Authors: VRASTI WANDA
Published: December 2011

This article responds to issues raised about global governmentality studies by Jan Selby, Jonathan Joseph, and David Chandler, especially regarding the implications of ‘scaling up’ a concept originally designed to describe the politics of advanced liberal societies to the international realm. In response to these charges, I argue that critics have failed to take full stock of Foucault's contribution to the study of global liberalism, which owes more to economic than political liberalism. Taking Foucault's economic liberalism seriously, that is, shifting the focus from questions of natural rights, legitimate rule, and territorial security to matters of government, population management, and human betterment reveals how liberalism operates as a universal, albeit not yet global, measure of truth, best illustrated by the workings of global capital. While a lot more translation work (both empirical and conceptual) is needed before governmentality can be convincingly extended to global politics, Foucauldian approaches promise to add a historically rich and empirically grounded dimension to IR scholarship that should not be hampered by disciplinary admonitions.
Genetic algorithm for optimization of L-shaped PIFA antennas
Authors: Nguyen Trong Duc , Duroc Yvan , Vu Van Yem , Vuong Tan Phu
Published: December 2011

Two new designs of the L-shaped Planar Inverted–F Antenna (PIFA) antennas with single and dual polarization operating at the frequency band for IEEE 802.11b/g standard with satisfactory radiation characteristics are presented. We further propose a genetic algorithm (GA) embedded in CST Microwave Studio for optimizing these antenna parameters. The agreement of simulation and measurement results shows the performance of our joint model. Also, they show that our dual-polarization antenna is suitable for indoor Multiple Input Multiple Output (MIMO) wireless environment applications.
Spectroscopic and magnetooptical investigations of spin-reorientation phase transition in TbFe3(BO3)4
Authors: Gnatchenko S. L. , Kachur I. S. , Piryatinskaya V. G. , Bedarev V. A. , Pashchenko M. I. , Malakhovskii A. V. , Bezmaternykh L. N. , Sukhachev A. L. , Temerov V. L.
Published: December 2011

Spectroscopic and magnetooptical investigations of spin-reorientation transition induced by a magnetic field in antiferromagnetic terbium ferroborate TbFe3(BO3)4 were performed. In the phase-transition region, a magnetic intermediate state with a periodic alternation of domains of initial and spin-flopped magnetic phases appears. As a result, a strong light scattering by the crystal takes place. It is shown that the main mechanism of light scattering is related to an appearance of the large Faraday rotation in a high-field magnetic phase. Visual polarization investigations of the domain structure in the intermediate state were carried out. The energy of the interphase boundary between the antiferromagnetic and high-field magnetic phases was calculated. The existence domain of the intermediate magnetic state was determined in the H–T coordinates.
Self organization of magnetic nanoparticles: A polarized grazing incidence small angle neutron scattering and grazing incidence small angle x-ray scattering study
Authors: Theis-Bröhl Katharina , Mishra Durgamadhab , Toperverg Boris P. , Zabel Hartmut , Vogel Britta , Regtmeier Anna , Hütten Andreas
Published: December 2011

Cobalt and magnetite nanoparticles were studied with small-angle x-ray and neutron scattering methods under grazing incidence for analyzing their structural and magnetic correlation on silicon substrates. The Co nanoparticles are in the ferromagnetic state while the iron oxide nanoparticles are superparamagnetic at room temperature. After spin-coating the iron oxide particles with a diameter of 20 nm and a very narrow size distribution of only 6% show very nice self-ordering on silicon substrates with nearly perfect six-fold symmetry as can be derived from scanning electron microscopy (SEM) images and from grazing incidence small angle x-ray scattering results. In contrast the dropcasted cobalt nanoparticles show a much higher roughness and less ordering. The corresponding SEM images and grazing incidence small angle neutron scattering maps with polarization of the incident beam reveal less pronounced structural and magnetic correlation.
The theta-temperature depression caused by topological effect in ring polymers studied by Monte Carlo simulation
Authors: Suzuki Jiro , Takano Atsushi , Matsushita Yushu
Published: December 2011

We studied equilibrium conformations of linear and ring polymers in dilute solutions over the wide range of segment number N of up to 2048 with Monte Carlo simulation, and evaluated N dependence of the radii of gyration, Rg, of chains. The polymer molecules treated in this study are assumed to be composed of beads and bonds, and they are put in a three-dimensional face-centered cubic (FCC) lattice. The values of Flory's critical exponent, ν, for linear and ring polymers were estimated from the N dependence of Rg, and the temperatures at which ν reach 1/2 were obtained. Here we define those as Θ-temperatures in this report. The simulation result shows that the Θ-temperature for ring polymers is evidently lower than that of the linear polymers, and the origin of the Θ-temperature depression is discussed. Since Rg of a ring polymer is smaller than that for a linear polymer at the same N and temperature, the segment density for a ring polymer is increased by the topological effect and the repulsive force between segments of a ring polymer at the Θ-temperature for a linear polymer is stronger. Thus, the origin of the Θ-temperature depression for ring polymers is the repulsive force emphasized by the topological effect of rings.
Kinetic solutions for electrons in multi-cusp ion source
Authors: Zhan Hualin , Hu Chundong
Published: December 2011

Some analytical kinetic solutions are obtained for the primary and plasma electrons in multi-cusp ion source. The characteristics based on these solutions are discussed, such as frictional coefficient, collision frequency, electron current, electron diffusion, electron density, and electrical conductivity. A code based on one of these solutions is developed to discuss the plasma electrons diffusion; the simulation results are qualitatively consistent with our current experiences.
Experimental realization and modeling of a subwavelength frequency-selective plasmonic metasurface
Authors: Li Ping-Chun , Zhao Yang , Alù Andrea , Yu Edward T.
Published: December 2011

We have modeled, fabricated, and characterized a plasmonic metasurface with subwavelength features, whose dominant resonance is the independent of incident angle and polarization, and sensitive only to the material composition and geometry of a single element. Higher-order resonances, associated with surface plasmon polariton (SPP) coupling and higher diffraction orders, are sensitive to the incident angle and the array periodicity and less pronounced compared with the metasurface resonance. Numerical simulations and theoretical analysis highlight a clear physical difference between the SPP resonances and the dominant metasurface collective resonance, whose properties may be of great interest for plasmonic solar cells and subwavelength color filters.
At-wavelength characterization of refractive x-ray lenses using a two-dimensional grating interferometer
Authors: Rutishauser Simon , Zanette Irene , Weitkamp Timm , Donath Tilman , David Christian
Published: December 2011

We report on the application of a two-dimensional hard x-ray grating interferometer to x-ray optics metrology. The interferometer is sensitive to refraction angles in two perpendicular directions with a precision of 10 nrad. It is used to observe the wavefront changes induced by a single parabolic beryllium focusing lens of large radius of curvature. The lens shape is reconstructed and its residual aberrations are analyzed. Its profile differs from an ideal parabolic shape by less than 2 μm or λ/50 at λ = 0.54 Å wavelength.
Interaction of nanosecond laser pulse with tetramethyl silane (Si(CH3)4) clusters: Generation of multiply charged silicon and carbon ions
Authors: Badani Purav M. , Das Soumitra , Mundlapati Venkateswara Rao , Sharma Pramod , Vatsa Rajesh K.
Published: December 2011

Present work reports significantly high levels of ionization, eventually leading to Coulomb explosion of Tetramethyl silane (TMS) clusters, on interaction with laser pulses of intensity ∼109 W/cm2. Tetramethyl silane clusters, prepared by supersonic expansion were photoionized at 266, 355 or 532 nm and the resultant ions were detected using time-of-flight mass spectrometer. It is observed that wavelength of irradiation and the size of the cluster are crucial parameters which drastically affect the nature of charge species generated upon photoionization of cluster. The results show that clusters absorb significantly higher energy from the laser field at longer wavelengths (532 nm) and generate multiply charged silicon and carbon ions which have large kinetic energies. Further, laser-cluster interaction at different wavelengths has been quantified and charge densities at 266, 355 and 532 nm are found to be 4x 1010, 5x 1010 and 5x 1011 charges/cm3 respectively. These unusual results have been rationalized based on dominance of secondary ionization processes at 532 nm ultimately leading to Coulomb explosion of clusters. In another set of experiments, multiply charged ions of Ar (up to +5 state) and Kr (up to +6 state) were observed when TMS doped inert gas clusters were photoionized at 532 and 355 nm. The extent of energy absorption at these two wavelengths is clearly manifested from the charge state of the atomic ions generated upon Coulomb disintegration of the doped cluster. These experiments thus demonstrate a novel method for generation of multiply charged atomic ions of inert gases at laser intensity of ∼ 109 W/cm2. The average size of the cluster exhibiting Coulomb explosion phenomena under giga watt intensity conditions has been estimated to be ∼ 6 nm. Experimental results obtained in the present work agree qualitatively with the model proposed earlier [D. Niu, H. Li, F. Liang, L. Wen, X. Luo, B. Wang, and H. Qu, J. Chem. Phys. 122, 151103(2005)] and point towards interaction of quasi-free electrons, generated during primary multiphoton ionization step, with a given wavelength in the presence of Coulombic field.
Physiological characterization of human muscle acetylcholine receptors from ALS patients
Authors: Palma Eleonora , Inghilleri Maurizio , Conti Luca , Deflorio Cristina , Frasca Vittorio , Manteca Alessia , Pichiorri Floriana , Roseti Cristina , Torchia Gregorio , Limatola Cristina , Grassi Francesca , Miledi Ricardo
Published: December 2011

Amyotrophic lateral sclerosis (ALS) is characterized by progressive degeneration of motor neurons leading to muscle paralysis. Research in transgenic mice suggests that the muscle actively contributes to the disease onset, but such studies are difficult to pursue in humans and in vitro models would represent a good starting point. In this work we show that tiny amounts of muscle from ALS or from control denervated muscle, obtained by needle biopsy, are amenable to functional characterization by two different technical approaches: “microtransplantation” of muscle membranes intoXenopusoocytes and culture of myogenic satellite cells. Acetylcholine (ACh)-evoked currents and unitary events were characterized in oocytes and multinucleated myotubes. We found that ALS acetylcholine receptors (AChRs) retain their native physiological characteristics, being activated by ACh and nicotine and blocked by α-bungarotoxin (α-BuTX), d-tubocurarine (dTC), and galantamine. The reversal potential of ACh-evoked currents and the unitary channel behavior were also typical of normal muscle AChRs. Interestingly, in oocytes injected with muscle membranes derived from ALS patients, the AChRs showed a significant decrease in ACh affinity, compared with denervated controls. Finally, riluzole, the only drug currently used against ALS, reduced, in a dose-dependent manner, the ACh-evoked currents, indicating that its action remains to be fully characterized. The two methods described here will be important tools for elucidating the role of muscle in ALS pathogenesis and for developing drugs to counter the effects of this disease.
Lexical reduplication and affective contents
Authors: Rossi Daniela
Published: December 2011

The purpose of this paper is to investigate how the use of a linguistic form (lexical reduplication) can communicate affective contents. Lexical reduplication, understood as the intentional repetition of a word, is defined as a pattern XX used to convey, on the one hand, a content which differs from the “basic” meaning of X by involving, for instance, intensification, narrowing, or expansion, and, on the other hand, an affective content that results from the evaluation of the state of affairs at hand. To test reduplication as well as the derivation of affective contents linked to its use, I have relied on a recognition task: after hearing a short story, participants were asked if the items presented on the screen occurred in the story or not. The results obtained suggest that the formal pattern of reduplication plays the role of a trigger.
Primary dyslipidaemias
Authors: Stalenhoef Anton F. H.
Published: December 2011

• Primary hyperlipidaemias are autosomal dominant or recessive inherited disturbances in lipid metabolism, which become manifest either from early childhood or later in life.

• Clinical manifestations are premature ischaemic vascular disease, xanthomatosis and other lipid depositions in the body, and acute pancreatitis.

• The molecular defect is explained by mutations in genes, which encode proteins that play a major role in the formation, secretion, transport, or uptake of lipoproteins.

• The most common forms of primary dyslipidaemias are multifactorial heterogeneous disorders with several genetic, metabolic, and environmental factors interacting and contributing to the clinical phenotype.

• Family investigation is usually crucial for proper diagnosis and case finding of persons at risk for vascular disease.
Secondary dyslipidaemias
Authors: Carmena Rafael , T. Real José
Published: December 2011

• Secondary causes including concurrent drug therapy should be sought and excluded in patients presenting with dyslipidaemia.

• Depending on the cause, treatment is of the underlying condition, for example, hypothyroidism.

• Lipid lowering is required in addition to treatment of the underlying cause in some conditions such as diabetes, kidney disease, and HIV/AIDS.

• Dyslipidaemia is commonly seen in type 2 diabetes and metabolic syndrome, and its treatment is an important component of overall management.