bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of a quadrupole ion trap with damping force by the two‐point one block method
Authors: Seddighi Chaharborj S. , Phang P. S. , Sadat Kiai S. M. , Majid Z. A. , Abu Bakar M. R. , Fudziah I. 
Published: May 2012

RATIONALEThe capabilities and performances of a quadrupole ion trap under damping force based on collisional cooling is of particular importance in high‐resolution mass spectrometry and should be analyzed by Mathieu's differential solutions. These solutions describe the stability and instability of the ion's trajectories confined in quadrupole devices. One of the methods for solving Mathieu's differential equation is a two‐point one block method. In this case, Mathieu's stability diagram, trapping parameters az and qz and the secular frequency of the ion motion wz, can be derived in a precise manner. The two‐point one block method (TPOBM) of Adams Moulton type is presented to study these parameters with and without the effect of damping force and compared to the 5th‐order Runge–Kutta method (RKM5). The simulated results show that the TPOBM is more accurate and 10 times faster than the RKM5. The physical properties of the confined ions in the r and z axes are illustrated and the fractional mass resolutions m/Δm of the confined ions in the first stability region were analyzed by the RKM5 and the TPOBM.METHODSThe Lagrange interpolation polynomial was applied in the derivation of the proposed method. The proposed method will be utilized to obtain a series solution directly without reducing it to first order equations.RESULTSThe problem was tested with the ion trajectories in real time with and without the effect of damping force using constant step size. Numerical results from the two‐point one block method have been compared with the fifth order Runge–Kutta method.CONCLUSIONSThe proposed two‐point one block method has a potential application to solve complicated linear and nonlinear equations of the charged particle confinement in a quadrupole field especially in fine tuning accelerators, and, generally speaking, in physics of high energy. Copyright © 2012 John Wiley & Sons, Ltd.
Simultaneous quantification of microcystins and nodularin in aerosol samples using high‐performance liquid chromatography/negative electrospray ionization tandem mass spectrometry
Authors: Gambaro Andrea , Barbaro Elena , Zangrando Roberta , Barbante Carlo 
Published: May 2012

RATIONALECyanobacteria are a small group of photosynthetic planktonic bacteria, producing a large group of strong hepatotoxins called microcystins (MCs). Many studies have been conducted to evaluate the presence of MCs and nodularin (NOD) in water or in marine organisms, but little research has been done on the atmospheric environment. Waterborne toxins can be found in the aerosol phase due to bubble‐bursting processes.METHODSThe aim of this study was to obtain a sensitive method for the simultaneous determination of trace concentrations of individual cyanotoxins in aerosol samples, using liquid chromatography coupled with a triple quadrupole (HPLC/MS/MS). During method development improved electrospray ionization was found in negative ion mode. In contrast with other authors, we have developed a chromatographic separation using alkaline conditions, thus achieving good resolution, improved electrospray ionization and therefore better sensitivity.RESULTSA sensitive analytical method was set up to simultaneously measure trace concentrations of cyanotoxins in aerosol samples in a single chromatographic analysis using the internal standard method. The limit of detection for all the toxins was determined to be between 1 fg/μL (MC LA and LF) and 9 fg/μL (NOD).CONCLUSIONSThe method was applied to ten aerosol samples from the Venice Lagoon. In these samples, trace concentrations of MC‐LA ranging between 90 fg m−3 and 706 fg m−3, MC‐LF between n.d. and 369 fg m−3 and MC‐LW between n.d. and 262 fg m−3. This is the first study to quantify the cyanotoxins in Venetian aerosol samples using the HPLC/(−)ESI‐MS/MS. Copyright © 2012 John Wiley & Sons, Ltd.
Autonomous scale control of multiagent formations with only shape constraints
Authors: Huang Huang , Yu Changbin , Wu Qinghe 
Published: May 2012

SUMMARYThis paper considers a novel problem of how to choose an appropriate geometry for a group of agents with only shape constraints but with a flexible scale. Instead of assigning the formation system with a specific geometry, here, the desired geometry is only characterized by its shape without any location, rotation, and most importantly, scale constraints. Optimal rigid transformation between two different geometries is discussed with especial focus on the scaling operation, and the cooperative performance of the system is evaluated by what we call the geometries' degrees of similarity with respect to the desired shape during the entire convergence process. The design of the scale when measuring the degree of similarity is discussed from constant value and time‐varying function perspectives, respectively. Fixed structured nonlinear control laws that are functions on the scale and the relative positions of agents are developed to guarantee the exponential convergence of the system to the assigned shape. Our research is originated from a three‐agent formation system and is further extended to multiple (n > 3) agents by defining a triangular complement graph. Simulations demonstrate that a formation system with the time‐varying scale function outperforms the one with an arbitrary constant scale, and the relationship between underlying topology and the system performance is further discussed according to the simulation observations. Moveover, the control scheme is applied to bearing‐only sensor–target localization to show its application potentials. Copyright © 2012 John Wiley & Sons, Ltd.
DiaSim: a simulator for pervasive computing applications
Authors: Bruneau Julien , Consel Charles 
Published: May 2012

SUMMARYPervasive computing applications involve both software concerns, such as any software system, and integration concerns, for the constituent networked devices of the pervasive computing environment. This situation is problematic for testing because it requires acquiring, testing, and interfacing a variety of software and hardware entities. This process can rapidly become costly and time‐consuming when the target environment involves many entities.This paper introduces DiaSim, a simulator for pervasive computing applications. To cope with widely heterogeneous entities, DiaSim is parameterized with respect to a description of a target pervasive computing environment. This description is used to generate both a programming framework to develop the simulation logic and an emulation layer to execute applications. Furthermore, a simulation renderer is coupled to DiaSim to allow a simulated pervasive system to be visually monitored and debugged.DiaSim has been implemented and used to simulate various pervasive computing systems in different application areas, demonstrating the generality of our parameterized approach. Copyright © 2012 John Wiley & Sons, Ltd.
Size and volume charts of fetal kidney, renal pelvis and adrenal gland
Authors: van Vuuren S. H. , Damen‐Elias H. A. M. , Stigter R. H. , van der Doef R. , Goldschmeding R. , de Jong T. P. V. M. , Westers P. , Visser G. H. A. , Pistorius L. R. 
Published: May 2012

ABSTRACTObjectiveTo establish reference curves for size and volume of the fetal kidney, renal pelvis and adrenal gland, as measured using ultrasound from the 15th week of gestation.MethodsThis was a prospective, longitudinal study of 96 fetuses in low‐risk singleton pregnancies, in which we performed serial ultrasound examinations at 4‐week intervals. The length and anteroposterior and transverse diameters of both kidneys, the anteroposterior and transverse diameters of the renal pelvises and the length of the adrenal glands were measured three times at each examination, with the average being used for further analysis. Reference charts were constructed using multilevel statistical analysis and comparisons were made with previously published charts derived from cross‐sectional data.ResultsWe present nomograms for fetal kidney dimensions and volume, renal pelvis dimensions and adrenal gland length. The new charts show differences in shape and have narrower percentile bands in comparison to previously published reference ranges.ConclusionsThese new charts of measurements of the fetal kidney, renal pelvis and adrenal gland, from a prospective, longitudinal study, may be useful in the diagnosis and assessment of pathology of the kidney and adrenal gland.
Climate change ‘science’ on the London stage
Authors: Bottoms Stephen 
Published: May 2012

AbstractThis article considers climate change as a contested cultural idea, which is mediated to the public through varying forms of cultural narrative whose conventions and rhetorics impact significantly on how the ‘story’ is told. Specifically, it examines four recent British stage plays, each of which depict climate change scientists as central characters. These are Steve Waters' The Contingency Plan (Bush Theatre, 2009), Mike Bartlett's Earthquakes in London (National Theatre, 2010), Richard Bean's The Heretic (Royal Court Theatre, 2011), and the multiauthored Greenland (National Theatre, 2011). The essay argues that these plays represent an evolutionary step forward from the rather crude, apocalyptic narratives apparent in mainstream film treatments of the subject, insofar that they attempt to grapple—in various ways—with the necessary uncertainty around scientific findings and future projections. They also attempt to dramatize the ‘new cultural politics of climate change’ (Smith) by examining the relationships between, and contrasting responsibilities of, scientists, politicians, and the lay public. This article considers various critical questions arising from the plays' varying treatments of these interactions. Waters' play sees a pragmatic, technocratic role for scientific advisers in government; Bean's argues for empirical purism (and satirises the UEA Climategate ‘scandal’ of 2009); Bartlett's presents a Lovelockian scientist figure as the tortured villain in a kaleidoscopic theatrical treatment of cultural despair (following the failure of 2009's Copenhagen Summit); Greenland presents scientists old and young as ethically engaged witnesses to environmental change. WIREs Clim Change 2012 doi: 10.1002/wcc.173This article is categorized under:

Trans‐Disciplinary Perspectives > Humanities and the Creative Arts
An Unprecedented Process of Peroxide Ion Formation and its Localization in the Crystal Structure of Strontium Peroxy‐HydroxyapatiteSr10(PO4)6(O2)x(OH)2–2x.
Authors: Kazin Pavel E. , Zykin Mikhail A. , Dinnebier Robert E. , Magdysyuk Oxana V. , Tretyakov Yury D. , Jansen Martin 
Published: May 2012

AbstractFormation of strontium peroxy‐hydroxyapatite solid solution Sr10(PO4)6(O2)x(OH)2–2x was studied on annealing the hydroxyapatite in the temperature range 900–1350 °C in oxygen, air, and argon atmosphere. The redox process was found to display unprecedented features: (i) the peroxide content increased with raising temperature, (ii) the peroxide content remained substantial even at a low oxygen pressure of 1.013 Pa, (iii) the peroxide content was extremely persistent, and even at a temperature of 1350 °C in oxygen atmosphere the peroxide groups substituted more than two‐third of the original hydroxide groups. Chemical processes consistent with these features are suggested. In the UV/Vis spectrum, an absorption peak at 300 nm was recorded, which was attributed to an electronic transition in the peroxide ion, since its intensity depended linearly on the peroxide content. In the Raman spectra, a weak band at 765–770 cm–1 was ascribed to symmetric stretching vibrations of O22–. The structures of the compounds were refined from powder X‐ray diffraction data using the Rietveld method supported by a maximum entropy method (MEM) electron density calculation. The peroxide ions are localized in the center of the hexagonal channel. At high concentration they tend to order with the associated vacancies along the channels. As a consequence, the width of the channel sections varies, the PO4 tetrahedra tilt, and the remote strontium atoms are displaced leading to changes in their coordination. Generally, the peroxide for hydroxide substitution manifests itself in the reduction of the overall channel diameter (and its volume), while the volume occupied by out‐of‐channel ions remains the same.
Preparation of Cationic [(R2N)P5Cl]+‐Cage Compounds from [(R2N)PCl]+and P4
Authors: Holthausen Michael H. , Weigand Jan J. 
Published: May 2012

AbstractThe reaction of several amino‐substituted mono‐ and dichlorophosphanes (R2N)nPCl3–n(n= 2, R =i‐Pr;n= 1, R =i‐Pr, Cy) with GaCl3to form phosphenium cations [(i‐Pr2N)2P]+(13+) and [(R2N)PCl]+(14a, b+) has been investigated. The isolation and fully characterization of the first amino‐ and chloro‐substituted phosphenium cation14b[GaCl4] was accomplished. The insertion of these phosphenium ions into P–P bonds of dissolved P4was examined. Amino‐ and chloro‐substituted phosphenium cations14a, b+readily form the corresponding P5+‐cages15a, b+. No reaction was observed for the less electrophilic diamino‐substituted phosphenium cation13+. The molecular structures of [14b][GaCl4] and [15b][Ga2Cl7] are presented and, furthermore, the intriguing NMR spectra of the P5+‐cations15a, b+are discussed.
Intravenous Lornoxicam Is More Effective than Paracetamol as a Supplemental Analgesic After Lower Abdominal Surgery: A Randomized Controlled Trial
Authors: Mowafi Hany A. , Elmakarim Ehab Abou , Ismail Salah , Al‐Mahdy Mohammed , El‐Saflan Abd Elhady , Elsaid Ayman S. 
Published: May 2012

AbstractBackgroundThe aim of this prospective, randomized, double‐blind study was to determine the more effective supplemental analgesic, paracetamol or lornoxicam, for postoperative pain relief after lower abdominal surgery.MethodsSixty patients scheduled for lower abdominal surgery under general anesthesia were randomly allocated to receive either isotonic saline (control group), intravenous paracetamol 1 g every 6 h (paracetamol group), or lornoxicam 16 mg then 8 mg after 12 h (lornoxicam group). Additionally pain was treated postoperatively with morphine patient‐controlled analgesia. Postoperative pain scores measured by the verbal pain score (VPS), morphine consumption, and the incidence of side effects were measured at 1, 2, 4, 8, 12, and 24 h postoperatively.ResultsMorphine consumption at 12 and 24 h was significantly lower in the lornoxicam group (19.25 ± 5.7 mg and 23.1 ± 6.5 mg) than in the paracetamol group (23.4 ± 6.6 mg and 28.6 ± 7.6 mg). Both treatment groups had less morphine consumption than the control group (28.5 ± 5 mg and 38.1 ± 6.6 mg) at 12 and 24 h, respectively. Additionally, VPS was reduced in the paracetamol and the lornoxicam groups compared with the control group both at rest and on coughing. Further analysis revealed that VPS in the lornoxicam group was significantly lower than that in the paracetamol group only during coughing. Drug‐related side effects were comparable in all groups.ConclusionsLornoxicam is superior to paracetamol for postoperative analgesia after lower abdominal surgery. However, paracetamol could be an alternative supplemental analgesic whenever an NSAID is unsuitable. Trial Registration: clinicaltrials.gov.identifier:NCT01564680.
Amino acid substitutions in the N-terminus, cord and α-helix domains improved the thermostability of a family 11 xylanase XynR8
Authors: Xue Huping , Zhou Jungang , You Chun , Huang Qiang , Lu Hong 
Published: May 2012

AbstractThe thermostability of xylanase XynR8 from uncultured Neocallimastigales rumen fungal was improved by combining random point mutagenesis with site-directed mutagenesis guided by rational design, and a thermostable variant, XynR8_VNE, was identified. This variant contained three amino acid substitutions, I38V, D137N and G151E, and showed an increased melting temperature of 8.8 °C in comparison with the wild type. At 65 °C the wild-type enzyme lost all of its activity after treatment for 30 min, but XynR8_VNE retained about 65 % activity. To elucidate the mechanism of thermal stabilization, three-dimensional structures were predicted for XynR8 and its variant. We found that the tight packing density and new salt bridge caused by the substitutions may be responsible for the improved thermostability. These three substitutions are located in the N-terminus, cord and α-helix domains, respectively. Hence, the stability of these three domains may be crucial for the thermostability of family 11 xylanases.
Early alcohol exposure disrupts visual cortex plasticity in mice
Authors: Lantz Crystal L. , Wang Weili , Medina Alexandre E. 
Published: May 2012

AbstractThere is growing evidence that deficits in neuronal plasticity underlie the cognitive problems seen in fetal alcohol spectrum disorders (FASD). However, the mechanisms behind these deficits are not clear. Here we test the effects of early alcohol exposure on ocular dominance plasticity (ODP) in mice and the reversibility of these effects by phosphodiesterase (PDE) inhibitors. Mouse pups were exposed to 5 g/kg of 25% ethanol i.p. on postnatal days (P) 5, 7 and 9. This type of alcohol exposure mimics binge drinking during the third trimester equivalent of human gestation. To assess ocular dominance plasticity animals were monocularly deprived at P21 for 10 days, and tested using optical imaging of intrinsic signals. During the period of monocular deprivation animals were treated with vinpocetine (20 mg/kg; PDE1 inhibitor), rolipram (1.25 mg/kg; PDE4 inhibitor), vardenafil (3 mg/kg; PDE5 inhibitor) or vehicle solution. Monocular deprivation resulted in the expected shift in ocular dominance of the binocular zone in saline controls but not in the ethanol group. While vinpocetine successfully restored ODP in the ethanol group, rolipram and vardenafil did not. However, when rolipram and vardenafil were given simultaneously ODP was restored. PDE4 and PDE5 are specific to cAMP and cGMP respectively, while PDE1 acts on both of these nucleotides. Our findings suggest that the combined activation of the cAMP and cGMP cascades may be a good approach to improve neuronal plasticity in FASD models.
Mass transport under standing waves over a sloping beach
Authors: Scandura Pietro , Foti Enrico , Faraci Carla 
Published: May 2012

AbstractThis paper deals with the mass transport induced by sea waves propagating over a sloping beach and fully reflected from a wall. It is shown that for moderate slopes the classical recirculation cell structure holds for small Reynolds numbers only. When the Reynolds number is large, the cells interact among themselves giving rise to the merging of the negative cells and the confinement of the positive ones near the bottom. Under such circumstances the fluid moves onshore near the bottom and offshore near the free surface. The seaward decrease of the vorticity produced at the bottom appears to be the reason for the merging phenomenon.
Does Collective Responsibility for Performance Alter Party Strategies? Policy-Seeking Parties in Proportional Systems
Authors: Adams James , Ezrow Lawrence , Merrill Samuel , Somer-Topcu Zeynep 
Published: May 2012

AbstractAdams and Merrill have developed a model of policy-seeking parties in a parliamentary democracy competing in a PR electoral system, in which party elites are uncertain about voters’ evaluations of the parties’valenceattributes such as competence, integrity and charisma. This article extends that model to situations where voters hold coalitions of partiescollectivelyresponsible for their valence-related performances, such as how voters evaluate governing parties’ competence in handling issues like the economy, crime and foreign policy crises. It may also be relevant to voters’ evaluations of proto-coalitions of opposition parties. Computations suggest the central substantive conclusions reported in Adams and Merrill extend to this generalized model, and that collective responsibility enhances coalition members’ incentives to converge to similar policy positions but depresses their prospects of achieving their policy objectives.
Eastern Europe Abroad: Exploring Actor-Networks in Transnational Movements and Migration History, The Case of the Bund
Authors: Wolff Frank 
Published: May 2012

SummaryThe “transnational turn” is one of the most discussed topics in historiography, yet it has inspired more theoretical tension than empirically saturated studies. This article combines both aspects by examining the transnational network formation of one of the most important social movements in late imperial Russia, the Jewish Labour Bund. It furthermore introduces into historiography one of the most fruitful theories in recent social sciences, “actor-network theory”. This opens the view on the steady recreation of a social movement and reveals how closely the history of the Bund in eastern Europe was interwoven with large socialist organizations in the New World. Based on a large number of sources, this contribution to migration and movement history captures the creation and the limits of global socialist networks. As a result, it shows that globalization did not only create economic or political networks but that it impacted the everyday lives of authors and journalists as well as those of tailors and shoemakers.
Malignant glomus tumour of larynx: first case report and literature review
Authors: Aslam N , Qazi Z-U-S , Ahmad A H , Khan R U 
Published: May 2012

AbstractObjective:We describe the first reported case of a malignant glomus tumour of the larynx.Method:Case report and review of the world literature concerning malignant glomus tumours.Results:A 37-year-old man presented with progressive hoarseness and dyspnoea. A smooth, right-sided laryngeal mass was found on flexible nasolaryngoscopy. Initial biopsy of this lesion was reported as a true ‘glomus tumour’, which is a benign lesion. Wide local excision was performed. The final histology of this specimen showed it to be a ‘malignant glomus tumour’. Immunohistochemistry was positive for smooth muscle actin, collagen type IV, vimentin and cluster of differentiation 34 glycoprotein. Total laryngectomy was then performed as a definitive curative procedure.Conclusion:Glomus tumour is rarely found in visceral locations. This tumour and its malignant counterpart are rare differential diagnoses of laryngeal masses.
Incidence of vestibular schwannoma and incidental findings on the magnetic resonance imaging and computed tomography scans of patients from a direct referral audiology clinic
Authors: Wong B Y W , Capper R 
Published: May 2012

AbstractObjective:To identify the incidence of vestibular schwannoma amongst patients referred from a direct referral audiology clinic, and also the number of incidental findings, as seen on magnetic resonance imaging or computed tomography scans.Method:Prospective data collection for patients referred from a direct referral audiology clinic due to audiological evidence of asymmetrical hearing loss. The audiograms, magnetic resonance imaging and computed tomography scans of patients with diagnosed vestibular schwannoma were subsequently reviewed.Results:A total of 4100 patients were seen during the study period, with 396 scans performed. Six (1.5 per cent) patients had vestibular schwannoma, while 12 (3 per cent) had significant incidental findings.Conclusion:Patients referred from the direct referral audiology clinic had a low incidence of vestibular schwannoma detection. Their detection rate for significant incidental findings was similar to previous reports. If the current protocol had not been in place, over 300 patients would have been needlessly added to the ENT clinic list. Thus, general practitioner referral to direct referral audiology clinics provides a cost-effective way of managing asymmetrical sensorineural hearing loss in older patients. The number of such clinics could be expanded.