bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties of ferrites with nonisometric shape of particles in organic coatings
Authors: Veselý David , Němec Petr , Kalendová Andréa
Published: May 2011

The pigments based on mixed metal oxides were synthesized at high temperature. The synthesized pigments XxZnyFe2O4(where X = Ca, Mg, x+y=1) had particles with a lamellar shape. The other type of synthesized ferrite pigments were core‐shell anticorrosion pigments where a layer corresponding to the XxZnyFe2O4 composition was applied onto the core – muscovite. The prepared pigments were characterized by means of X‐ray diffraction analysis, particle size distribution measurements, and scanning electron microscopy. The synthesized anticorrosion pigments were used to formulate alkyd paints that were tested in corrosion atmospheres. Good anticorrosion efficiency was detected for all the synthesized pigments. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical properties and crystallization kinetics of (TeO2)(ZnO)(TiO2) glasses
Authors: Kabalci Idris , Körpe Neşe Öztürk , Duran Tuğba , Özdemir Mustafa
Published: May 2011

Ternary tellurite based glasses in the (TeO2)(ZnO)(TiO2) system were prepared and its optical properties and crystallization kinetics investigated by using UV‐VIS spectrophotometer and differential thermal analyzer (DTA). All the glasses were transparent from visible to near infrared region for different ZnO glass compositions (x=0.05, 0.10, 0.20, and 0.30 mol). In the experiment, optical band gap and Urbach energies were estimated from the optical absorption spectra between 400 and 800 nm wavelength region. The observed results confirm that the addition of ZnO glass composition from 0.05 to 0.30 mol increases the optical band gap energy from 2.94 to 3.0 eV. In addition, glass transition (Tg), crystallization (Tp) and melting temperature (Tm) were determined by using the DTA plots. Finally, DTA results obtained with a heating rate of 20°C/min show that the peak crystallization temperature increases from 463 to 533 °C as the ZnO content increases from 0.05 to 0.30 mol (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Silver doped As2S3 chalcogenide films: A diffusion study
Authors: Lőrinczi Adam , Popescu Mihai , Sava Florinel , Velea Alin , Şimăndan Iosif‐Daniel
Published: May 2011

Photo‐diffusion of silver across an As2S3 thin film layer is studied, as continuing some earlier work about surface morphology modifications in double‐layer structures of Ag and As2S3, and some qualitative preliminary results on lateral Ag diffusion in As2S3 thin films. An estimation of the Ag film's dissolution rate and the diffusion front's advancement rate in As2S3 is given based on cross‐section measurements.

In order to understand better the diffusion mechanism of Ag in As2S3, a structural model of the As2S3 matrix is used to estimate the amount of silver which might be hosted by an As2S3 layer in terms of molar ratio, and an interaction mechanism of the Ag with the chalcogenide matrix is proposed (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Interstitial water and the formation of low barrier hydrogen bonds: A computational model study
Authors: Lao Ka‐Un , Lankau Timm , Fang Teng‐I , Zou Jian‐Wei , Yu Chin‐Hui
Published: May 2011

The B3LYP/D95+(d,p) analysis of the uncharged low barrier hydrogen bond (LBHB) between 4‐methyl‐1H‐imidazole (Mim) and acetic acid (HAc) shows that uncharged LBHBs can be formed either by adding three water molecules around the cluster or by placing the Mim–HAc pair in a dielectric environment created by a polarizable continuum model with a permittivity larger than 20.7. The permittivity of environment around uncharged LBHB can be lowered significantly by including water molecules into the system. A Mim–HAc LBHB stabilized with one water molecule observed in diethyl ether (ε = 4.34), with two water molecules in toluene (ε = 2.38), and with three water molecules in vacuo (ε = 1). Solvation models with different numbers of water molecules predict average differences in the proton affinities of the hydrogen bonded bases (ΔPA) for stable uncharged LBHB systems in vacuo to be 91.5 kcal/mol being different from the ΔPA values close to zero in charge‐assisted LBHB systems. The results clearly indicate that small amounts of interstitial water molecules at the active site of enzymes do not preclude the existence of LBHBs in biological catalysis. Our results also show that interstitial water molecules provide a useful clue in the search for uncharged LBHBs in an enzymatic environment and the number of water molecules can be used as a relative measure for the polarity around the direct environment of LBHBs. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Scientific argument and explanation: A necessary distinction?
Authors: Osborne Jonathan F. , Patterson Alexis
Published: May 2011

In this paper, we argue that there is an emergent confusion in the literature in the use of the terms “argument'' and “explanation.” Drawing on a range of publications, we point to instances where these terms are either used inappropriately or conflated. We argue that the distinction between these two constructs is, however, important as a lack of clarity of fundamental concepts is problematic for a field. First, a lack of common conception hinders effective communication and, second, it makes defining the nature of the activity we might expect students to engage in more difficult. Drawing on a body of scholarship on argument and explanation, this paper is an attempt to clarify the distinction and to explain why such a distinction might matter. © 2011 Wiley Periodicals, Inc. Sci Ed 95:627–638, 2011
Working toward a stronger conceptualization of scientific explanation for science education
Authors: Braaten Melissa , Windschitl Mark
Published: May 2011

Scientific explanation plays a central role in science education reform documents, including theBenchmarks for Science Literacy, theNational Science Education Standards, and the recent research report,Taking Science to School. While scientific explanation receives significant emphases in these documents, there is little discussion or consensus within the science education community about the nature of explanation itself. However, debates about scientific explanation have been a mainstay for philosophers of science for decades. We argue that a more clearly articulated conceptualization of scientific explanation for science education is necessary for making the vision of science education reform a reality. In this essay, we use major philosophical theories of scientific explanation as lenses to examine how the science education community has constructed the idea of explanation. We also examine instructional practice in school science settings, including our own classrooms, where teachers and students are working to explain natural phenomena. Using these examples, we offer suggestions for preparing both educators and young learners to engage in explanatory discourses that are reasonably accountable to authentic epistemic practice in science. © 2011 Wiley Periodicals, Inc.Sci Ed95:639–669, 2011
A novel watermarking method for software protection in the cloud
Authors: Yu Zhiwei , Wang Chaokun , Thomborson Clark , Wang Jianmin , Lian Shiguo , Vasilakos Athanasios V.
Published: May 2011

With the rapid development of cloud computing, software applications are shifting onto cloud storage rather than remaining within local networks. Software distributions within the cloud are subject to security breaches, privacy abuses, and access control violations. In this paper, we identify an insider threat to access control which is not completely eliminated by the usual techniques of encryption, cryptographic hashes, and access‐control labels. We address this threat using software watermarking. We evaluate our access‐control scheme within the context of a Collaboration‐oriented Architecture, as defined by The Jericho Forum. Copyright © 2011 John Wiley & Sons, Ltd.
Hydrothermal modifications of tropical tuber starches – Effect of ANN on the physicochemical, rheological and gelatinization characteristics
Authors: Jyothi Alummoottil N. , Sajeev Moothandasserry S. , Sreekumar Janardhanan
Published: May 2011

Cassava, sweet potato and arrowroot starches were hydrothermally modified by ANN under different conditions of temperature, moisture and time duration of treatment and the properties are compared. ANN brought about changes in swelling volume, solubility, gelatinization and rheological properties. The three starches behaved differently after the treatment. All the three tuber starches showed decrease in swelling volume after ANN treatment. The solubility decreased for cassava starch, whereas it slightly increased for majority of annealed sweet potato starches and significantly increased for arrowroot starch. For cassava starch, there was a decrease in peak viscosity, but for the other two starches, it increased after ANN. Differential scanning calorimetric studies showed that ANN resulted in a narrowing of DSC patterns for all the starches. The effect of ANN on the dynamic rheological properties was found to depend up on the source of starch. The modification resulted in increased gel hardness, gumminess, adhesiveness and decreased springiness for the starch gels. Tuber starches became less susceptible to enzyme action after ANN.
Effect of dual modification of banana starch and storage time on thermal and crystallinity characteristics of its films
Authors: Zamudio‐Flores Paul B. , Gutierrez‐Meraz Felipe , Bello‐Pérez Luis A.
Published: May 2011

Banana starch was oxidized at three different levels and subsequently acetylated. This double modified banana starch was used for film preparation with the addition of glycerol. Thermal and crystallinity properties were evaluated. Acetylation decreased the peak temperature and enthalpy of double modified banana starch. When the oxidation level and storage time increased in films elaborated with the double modified banana starch, both thermal parameters increased as well. The Tg showed slight changes in films prepared with the double modified banana starch compared to its oxidized counterpart, and similar patterns were found when oxidation levels increased in double modified films. However, a decrease in the Tg was determined with the storage time in films prepared with oxidized and double modified starches. Films prepared with the double modified banana starch presented lower percentage of crystallinity than its oxidized counterpart, nevertheless at higher storage periods, crystallinity levels increased. Thermal and crystallinity properties of films prepared with double modified banana starch could be used to understand the behavior during their application.
Applying formal methods to PCEP: an industrial case study from modeling to test generation
Authors: Hwang Iksoon , Cavalli Ana R. , Lallali Mounir , Verchere Dominique
Published: May 2011

This paper presents the experimental results in applying formal methods to an industrial protocol for constraint‐based path computation, called Path Computation Element Communication Protocol (PCEP). The experiments include a number of major activities in model‐based testing from modeling to test generation. From the PCEP specification defined by IETF (Internet Engineering Task Force), the functionalities of PCEP are divided into two parts: application and protocol. The protocol part of PCEP is then described in the IF (Intermediate Format) language which is based on communicating timed automata. A number of basic requirements are identified from the PCEP specification and then described as properties in IF. Based on these properties, the validation and verification of the formal specification are carried out using the IF toolset. Test cases are generated using an automatic test generation tool, called TestGen‐IF, which uses partial state space exploration guided by test purposes. As a result, some errors and ambiguities have been found in the PCEP standard specification. Copyright © 2011 John Wiley & Sons, Ltd.
Image denoising using pulse coupled neural network with an adaptive Pareto genetic algorithm
Authors: Zhang Deng , Mabu Shingo , Hirasawa Kotaro
Published: May 2011

Recently, pulse coupled neural network (PCNN) attracts much attention in image denoising as a nonlinear filtering technique. The PCNN‐based anisotropic diffusion (PCNN‐AD) method has been proposed previously for flicker noise reduction and its effectiveness has been demonstrated. Using the visual characteristics of PCNN, PCNN‐AD has also solved the problem of AD that AD is not able to suppress the isolate noise. However, there are still two drawbacks in PCNN‐AD, that is, time consuming and PCNN parameters' estimation. In order to improve the efficiency and the denoising performance of PCNN‐AD, a PCNN‐based method with an adaptive Pareto genetic algorithm (GA‐PCNN) has been proposed to restrain from additive white Gaussian noise (AWGN) in this paper. GA‐PCNN firstly integrates the PCNN and AD as a parallel system, then, optimizes the parameters of a simplified PCNN by the adaptive Pareto GA. Experimental results indicate that GA‐PCNN has better performances than the previous denoising techniques, i.e. median filter, Wiener filter, AD filter, and PCNN‐AD. The effectiveness of GA‐PCNN on AWGN reduction and edge preservation are shown finally. The results will also contribute to denoising in CMOS image sensors in the future. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Lewis‐Base Stabilized N‐Silver(I) Succinimide Complexes: Synthesis, Crystal Structures and Their Use as CVD‐Precursors
Authors: Tao Xian , Shen Ke‐Cheng , Wang Yu‐Long , Shen Ying‐Zhong
Published: May 2011

Four Lewis‐base stabilized N‐silver(I) succinimide complexes of type [Ln·Rm·AgNC4H4O2] (L = N,N,N′,N′‐tetramethylethylenediamine (TMEDA), n = 1, m = 0, 2a; L = P(OEt)3, n = 2, m = 0, 2b; L = PPh3, m = 0, n = 2, 2c; L = P(OMe)3, R = TMEDA, n = 1, m = 1, 2d) were prepared by a “one‐pot” synthesis methodology and characterized. The molecular structures of 2a and 2c have been determined by using X‐ray single crystal analysis. Complex 2a exists as ion pair {[Ag(TMEDA)2]+[Ag(NC4H4O2)2]–} in the solid state and complex 2c is a monomer with the three‐coordinate silver atom. Complex 2b was used as precursor in the deposition of silver for the first time by using MOCVD technique. The silver films obtained were characterized using scanning electron microscopy (SEM) and energy‐dispersion X‐ray analysis (EDX). SEM and EDX studies show that the dense and homogeneous silver films could be obtained.
Early Postoperative and One Year Results of a Randomized Controlled Trial Comparing the Impact of Extralight Titanized Polypropylene Mesh and Traditional Heavyweight Polypropylene Mesh on Pain and Seroma Production in Laparoscopic Hernia Repair (TAPP)
Authors: Bittner R. , Schmedt C.‐G. , Leibl B. J. , Schwarz J.
Published: May 2011

Background

Today the main goals of inguinal hernia repair are maximum postoperative comfort and a minimal rate of chronic pain. This randomized trial compares these parameters after laparoscopic hernia repair (TAPP) using an extralight titanized polypropylene mesh (ELW group) TiMesh® 16 g/m2 without any fixation with those using a standard heavyweight mesh (HW) Prolene 90 g/m2 fixed in a standardized way with two absorbable sutures.

Methods

Three hundred patients with an inguinal hernia and a defect diameter ≤3 cm were included in the trial. Patients were assessed for pain, foreign body sensation, and physical activities preoperatively, early postoperatively, at 4 weeks, 6 months, and 1 year by questionnaire and were examined clinically. Postoperatively, seroma formation was measured by ultrasound.

Results

One year after TAPP, the frequency of chronic pain was not greater than 3%, with no difference between the two mesh groups; in no patient was intensity of pain higher than VAS 40. In the early postoperative period, 40% of the patients in the titanized ELW group needed pain medication compared with 52.7% in the HW group (P = 0.0378). Foreign body sensation was not different between the groups but there was significantly less impairment of physical activities (P = 0.0425) and seroma production (P = 0.0415) in the titanized ELW group compared to the HW group in the early postoperative period.

Conclusion

Use of titanized ELW mesh for laparoscopic hernia repair did not affect the rate of chronic pain but it seems to improve early postoperative convalescence. Its use without any fixation can be recommended in TAPP for inguinal hernia patients with a defect size ≤3 cm.
Nash–Moser iteration and singular perturbations
Authors: Texier Benjamin , Zumbrun Kevin
Published: May 2011

We present a simple and easy-to-use Nash–Moser iteration theorem tailored for singular perturbation problems admitting a formal asymptotic expansion or other family of approximate solutions depending on a parameter

\varepsilon \rightarrow 0

. The novel feature is to allow loss of powers of
ε
as well as the usual loss of derivatives in the solution operator for the associated linearized problem. We indicate the utility of this theorem by describing sample applications to (i) systems of quasilinear Schrödinger equations, and (ii) existence of small-amplitude profiles of quasilinear relaxation systems in the degenerate case that the velocity of the profile is a characteristic mode of the hyperbolic operator.
Secondary Haemorrhage following Transurethral Resection of Bladder Tumour — Is it Always Related to Infection?
Authors: Heer R. , Glendinning R.J. , Nesbitt C.N. , Pal D. , Rix D. , Menezes P. , Johnson M.I.
Published: May 2011

Background:

We reviewed the empirical use of antibiotics in patients with secondary haemorrhage following transurethral resection of bladder tumour.

Patients and methods:

A retrospective review of 2830 patients undergoing TURBT between January 2006 and April 2009 was performed from two large independent urology centres in the UK. Patients with secondary haemorrhage were identified and their urine culture results and risk factors for bleeding were studied.

Result:

Secondary haemorrhage causing hospital admission was seen in 2% (51 cases). However, only 14% of these cases had significant bacteriuria on urine culture. In patients with secondary haemorrhage we show potential risk factors for bacteriuria: resection weight greater than 2g (71% versus 28%), muscle invasive bladder cancer (43% versus 20%) and macroscopic residual disease (43% versus 12%); although they did not reach statistical significance. Interestingly there was no significant difference in the clinical parameters supportive of infection between patients with bacteriuria and sterile urine — in particular only 1/51 had a temperature of greater than 37.5°C. Nevertheless, 73% (37/51) of patients were treated with antibiotics.

Conclusion:

Typically, patients with secondary haemorrhage following TURBT do not have evidence of demonstrable infection and only a few had evidence of bacteriuria. Routine prescription of antibiotics in secondary haemorrhage following TURBT is therefore not justified.
Antinociceptive effect of paeoniflorin via spinal α2‐adrenoceptor activation in diabetic mice
Authors: Lee Keiko K. , Omiya Yuji , Yuzurihara Mitsutoshi , Kase Yoshio , Kobayashi Hiroyuki
Published: May 2011

Background: Shakuyakukanzoto (SKT) has been shown to modulate nociception in streptozotocin‐induced diabetic mice via selective activation of the descending noradrenergic systems. However, the active components of SKT that exert the analgesic effect remain unknown. Here, we administered Glycyrrhizae radix (G. radix), Paeoniae radix (P. radix), and the two active constituents of P. radix, paeoniflorin and albiflorin, to determine the components that stimulate spinal α2‐adrenoceptors by promoting noradrenaline release.

Methods: The two SKT components were separately administered to diabetic and non‐diabetic mice. A tail‐pressure test was used to determine the nociceptive threshold between 0 and 3 h after oral dosing. The time‐course profiles of the nociceptive threshold (g) and the area under the time response curve (AUC) were evaluated. Yohimbine, an α2‐adrenoceptor antagonist, was intrathecally injected 15 min after paeoniflorin administration.

Results: P. radix and G. radix did not induce significant antinociception in non‐diabetic mice. However, P. radix (250, 500 mg/kg) dose‐dependently and significantly increased the nociceptive threshold in diabetic mice between 0.5 and 2 h after administration, whereas all the tested doses of G. radix did not increase the nociceptive threshold. Both paeoniflorin (30 mg/kg) and albiflorin (10 mg/kg) significantly elevated the nociceptive threshold between 0.5 and 3 h and between 0.5 and 1 h after administration, respectively. The antinociceptive effect of paeoniflorin (30 mg/kg) was completely abolished by yohimbine.

Conclusion: Our findings suggest that paeoniflorin is the key antinociceptive component in SKT that increases noradrenaline release and activates α2‐adrenoceptors to modulate spinal nociceptive transmission in diabetic neuropathy.
Prevalence of psychiatric disorders in sick listed chronic low back pain patients
Authors: Reme Silje Endresen , Tangen Tone , Moe Trygve , Eriksen Hege Randi
Published: May 2011

Background: Previous findings have shown a high degree of comorbid psychopathology in chronic low back pain (CLBP), but less is known about the broad range of comorbid psychiatric disorders. The prevalence is reported to be between 40% and 100% depending on methods being used, sample or setting.

Aims: To assess the prevalence of psychiatric comorbidity in a population of CLBP patients, using a psychiatric diagnostic interview.

Methods: 565 patients sick listed between 2 and 10 months for unspecific LBP were included in the study. All were recruited as part of an ongoing trial in secondary care, and were assessed with the Mini‐International Neuropsychiatric Interview (MINI), which is a short structured diagnostic interview for DSM‐IV and ICD‐10 psychiatric disorders.

Results: The prevalence of current psychiatric disorders was 31%. The diagnoses included 19 Axis I disorders, with the most common being somatoform disorders (18%) and anxiety disorders (12%). Major depressive disorders were reported in 4%. There were no gender differences in prevalence of psychiatric disorders.

Conclusions: In a large population of CLBP patients, 31% fulfilled the criteria for at least one current psychiatric disorder when measured with a diagnostic interview. The diagnoses included a wide range of psychiatric disorders, with the most common being somatoform disorders (18%) and anxiety disorders (12%). The results imply that screening CLBP patients for psychiatric comorbidity in secondary care is important since psychopathology may have serious consequences for prognosis, outcome and health care utilization.
Ubiquitylation and the Fanconi anemia pathway
Authors: Garner Elizabeth , Smogorzewska Agata
Published: May 2011

The Fanconi anemia (FA) pathway maintains genome stability through co‐ordination of DNA repair of interstrand crosslinks (ICLs). Disruption of the FA pathway yields hypersensitivity to interstrand crosslinking agents, bone marrow failure and cancer predisposition. Early steps in DNA damage dependent activation of the pathway are governed by monoubiquitylation of FANCD2 and FANCI by the intrinsic FA E3 ubiquitin ligase, FANCL. Downstream FA pathway components and associated factors such as FAN1 and SLX4 exhibit ubiquitin‐binding motifs that are important for their DNA repair function, underscoring the importance of ubiquitylation in FA pathway mediated repair. Importantly, ubiquitylation provides the foundations for cross‐talk between repair pathways, which in concert with the FA pathway, resolve interstrand crosslink damage and maintain genomic stability.
Insight from genome‐wide association studies in rheumatoid arthritis and multiple sclerosis
Authors: Suzuki Akari , Kochi Yuta , Okada Yukinari , Yamamoto Kazuhiko
Published: May 2011

Autoimmune diseases are caused by multiple genes and environmental effects. In addition, genetic contributions and the number of associated genes differ among different diseases and ethnic populations. Genome‐wide association studies (GWAS) on rheumatoid arthritis (RA) and multiple sclerosis (MS) show that these diseases share many genetic factors. Recently, in addition to the major histocompatibility complex (MHC) gene, other genetic loci have been found to be associated with the risk for autoimmune diseases. This review focuses on the search for genetic variants that influence the susceptibility to RA and MS as typical autoimmune diseases and discusses the future of GWAS.
Heightened locomotor‐activating effects of amphetamine administered into the nucleus accumbens in adolescent rats
Authors: Mathews I.Z. , Brudzynski S.M. , McCormick C.M.
Published: May 2011

There is a shift in sensitivity to systemically administered psychostimulants in adolescence, as evidenced by less amphetamine‐induced locomotor activity in adolescent compared to adult rodents. Locomotor activating effects of amphetamine are dependent on drug actions in the core of the nucleus accumbens (NAc), but the contribution of this region to age differences in amphetamine sensitivity has not been studied directly. In the present study, we investigated the development of the NAc using targeted injections of amphetamine (0, 3, or 6 μg/side) directly into the NAc core in early (postnatal day 30; P30) or late (P45) adolescence, or in adulthood (P75). Locomotor activity was recorded during two 1 h sessions, 48 h apart. Amphetamine increased locomotor activity at all ages. P45 rats were more active than adults only at the 3 μg/side dose, but this difference was not significant when baseline activity was taken into account. In contrast, P30 rats were more active than adults at the 6 μg/side dose, indicating that the magnitude of the locomotor response is highest in early adolescence. Results of the present study are the first to directly show a developmental difference in the sensitivity of the NAc to amphetamine under conditions in which the influence of pharmacokinetic factors and regulatory brain regions is minimized.
Expanding the Application of the Tablet Processing Workstation to Support the Sample Preparation of Oral Suspensions
Authors: Opio Alex Manuel , Nickerson Beverly , Xue Gang , Warzeka John , Norris Ken
Published: May 2011

Sample preparation is the most time-consuming part of the analytical method for powder for oral suspension (POS) assay, purity, and preservative analysis, as this involves multiple dilution and filtration steps. The Tablet Processing Workstation (TPW) was used to automate the sample preparation of a POS formulation. Although the TPW is typically used to automate the preparation of solid oral dosage forms and powders, it contains all of the necessary components to perform POS sample preparation. The TPW exhibited acceptable repeatability in testing 3 lots using 10 replicate preparations per lot. Acceptable linearity of the drug and preservative in the presence of excipients was demonstrated over the range corresponding to 50–150% of intent. Accuracy showed suitable recoveries for all points evaluated. TPW results were shown to correlate to results obtained with the manual method. The TPW method was used to prepare samples in support of manufacturing scale-up efforts. With the efficiencies gained using the TPW, it was possible to analyze a large number of samples generated during process development activities for the POS formulation with minimal human intervention. The extensive data enabled trending of the manufacturing development runs and helped to identify optimization strategies for the process.
Fully Automated Microinjection System for Xenopus laevis Oocytes with Integrated Sorting and Collection
Authors: Graf Siegfried F. , Madigou Thierry , Li Ruoya , Chesné Christophe , Stemmer Andreas , Knapp Helmut F.
Published: May 2011

Microinjection is the most flexible transfection method in terms of choice of reagents to inject into cells. But this method lacks the high throughput to compete with less flexible methods like chemical- or viral-based approaches. Various approaches have been pursued to increase the throughput by automating the microinjection process. However, these approaches focused solely on the microinjection itself and disregarded the tasks before and after the injection, which also belong to the critical time path of the whole process, that is, sorting out viable cells from a cell suspension, placing the cell for injection, and collecting the cell after the injection. In the approach with our XenoFactor, we demonstrate a system capable of running the whole process automatically. By optimizing the XenoFactor for Xenopus laevis oocytes, we could demonstrate the successful automated injection. Starting from a suspension with a mixture of defolliculated oocytes at different stages and quality levels, the manual approach requires 1 day in total for the preparation of 400 microinjected oocytes. The XenoFactor takes only 4 h for the same amount and delivers injected oocytes of reproducible quality and without the fatigue symptoms experienced during the manual approach.
Centrosome clustering and chromosomal (in)stability: A matter of life and death
Authors: Krämer Alwin , Maier Bettina , Bartek Jiri
Published: May 2011

Centrosome abnormalities occur commonly in cancer, and contribute to chromosomal instability and tumorigenesis. New evidence on a phylogenetically conserved mechanism termed ‘centrosomal clustering’ provides exciting insights into how cells with supernumerary centrosomes adapt to avoid lethal multipolar divisions. Here, we highlight the emerging molecular basis of centrosome clustering, and its impact on asymmetric divisions of stem cells, chromosomal (in)stability and malignant transformation. Finally, pharmacological inhibition of centrosome clustering promises to selectively target tumor cells.
New insights into the sources of magnetic anomalies in the Levant
Authors: Rybakov M. , Goldshmidt V. , Hall J.K. , Ben-Avraham Z. , Lazar M.
Published: May 2011

The magmatic characteristics of the Levant were investigated by combining recompiled regional scale magnetic maps, revised petrophysical and gravity databases and previous interpretations. In the study area, the inclination of the Earth’s magnetic field vector is low and the total magnetic intensity map is, therefore, difficult to interpret for location and strike of magnetic bodies. Hence a pole-reduced magnetic map was compiled. The integrated interpretation of magnetic and local gravity anomalies allowed for the estimation of depth and size of magmatic bodies and, in some cases, permitted identification of their composition. Reliability and accuracy of the results were approximated by forward modeling and by comparison with seismic reflection and drill-hole data.

The study area was divided into five regions of consistent regional-scale magnetic patterns with more or less distinct boundaries. This was based not only on recognition of formal magnetic patterns but also on correlation with known (or expected) geology. The strong coincident magnetic and positive gravity anomalies probably correspond to ophiolite massifs in the northern part of the study area and basic magmatic intrusions in the southern part. Strong magnetic anomalies, which are not associated with positive gravity anomalies, most likely correspond to Mesozoic and Cenozoic volcanics located mainly in the central part of the region. The absence of magnetic anomalies in some areas suggests the lack of basic magmatic bodies (volcanic or plutonic) but provides no information on the presence of acid magmatics (granite, etc.).
Magnetic relaxation of a horizontal layer: Effect on TEM data
Authors: Kozhevnikov N.O. , Antonov E.Yu.
Published: May 2011

We have modeled central-loop and coincident-loop transient responses of a magnetically viscous layer sandwiched between two nonmagnetic ones. The coincident-loop transients show exponential voltage decrease (at a fixed delay time), at any thickness h2 of the magnetic layer, with an increasing depth to the latter (h1) or the loop height if the layer is exposed on the ground surface. The patterns of central-loop transients are different from those of the coincident-loop ones and from one another for thin and thick magnetic layers. Namely, the voltage first rises to its maximum and then falls as the depth to the magnetic layer (h1) increases, if it is thin: the thinner the layer, the more prominent the peak. If the layer is thick, the voltage decreases monotonically with its depth (or with loop height above the ground). Voltage grows, first rapidly and then progressively more slowly, at ever greater thicknesses of the magnetic layer in both loop configurations. At large h2, the effect from the magnetic layer becomes similar to that from a magnetically viscous halfspace. These features of the transient responses have to be taken into account in planning and conducting TEM surveys, as well as in a geological interpretation of the TEM data affected by natural and/or man-caused magnetically viscous ground. In the general case, the turn-off of the transmitter current induces eddy current in the ground beneath the loop, which decays at a rate proportional to the ground resistivity. The eddy current decay and magnetic relaxation processes being independent at conductivities (resistivities) common to the real subsurface, the effect of the former can be allowed for using the superposition principle. This principle implies that the total response of a magnetically viscous conductor is a sum of the magnetic relaxation and eddy current components.
Geochemistry, petrogenesis and geodynamic origin of basalts from the Katun’ accretionary complex of Gorny Altai (southwestern Siberia)
Authors: Safonova I.Yu. , Buslov M.M. , Simonov V.A. , Izokh A.E. , Komiya T. , Kurganskaya E.V. , Ohno T.
Published: May 2011

The paper presents new data on geochemistry (major and trace elements, isotopes) and petrology (composition of phenocrysts and mineral thermometry) of basalts from the Early Cambrian Katun’ accretionary complex of the Kuznetsk–Altai island arc (Gorny Altai). We also discuss the geodynamic settings of the formation of basalts based on petrologic, geochemical and isotope data taking into account their relationships with associated sedimentary rocks of oceanic origin and with terrigenous sedimentary rocks of the accretionary complex. The Late Neoproterozoic basalts associated with siliceous sediments are characterized by medium TiO2 and Zr/Nb, flat REE patterns and Nb/Lapm < 1 (MORB-type oceanic floor basalts). The oceanic floor basalts are represented by high- and low-magnesium varieties. The Early Cambrian basalts (Manzherok Formation) were formed in an oceanic island setting (OIB-type). They occur in sections consisting of paleo-oceanic island basalts alternated with siliceous-terrigenous-carbonate sediments of slope facies. The Manzherok basalts are characterized by high crystallization temperatures (1175 °C), and enriched incompatible elements (LREE, Ti, Nb), whose variations suggest a mantle plume source and variable degrees of partial melting in the spinel and garnet stability fields. The low to high-Mg Middle Cambrian basalts of the Ust’-Sema Formation occur as subparallel dikes and lava flows, which cut and overlap the accretionary complex. The basalts are characterized by low TiO2, Nb, LREE, high Zr/Nb and, compared to the OIB-type basalts, lower temperatures of crystallization, 1047 °C and 1138 °C for the low- and high-Mg varieties, respectively. Geochemically, the low-Mg basalts of the Ust’-Sema Formation are close to MORB, and the high-Mg basalts—to island-arc tholeiites. Such a combination of geochemical and geological data suggest that the low-Mg basalts of the Ust’-Sema Formation formed during ridge subduction, and the high-Mg basalts formed in a suprasubduction setting, at the crust-mantle boundary.
Picturing theImperator: Passenger Shipping as Art and National Symbol in the German Empire
Authors: Russell Mark A.
Published: May 2011

The morning of May 23, 1912, witnessed the christening of a new German icon. For many Germans, it was a wonder of the modern age, a powerful symbol of the nation's achievements in industry, engineering, and technology. For others, it was the embodiment of all the evils wrought by political, social, and cultural transformation. Some said it expressed the character of the German people, in a manner similar to Cologne Cathedral and Sanssouci, the palace of Frederick the Great. But there were those who thought it “appeared as a typical manifestation of the new Germany, with its huckstering and obtrusive manners, more a snobbism than a symbol of German competence.” TheKaiserwas fascinated by this expression of the ambition, ingenuity, and might of an Empire in which he believed power rested with himself, the Prussian nobility, and a powerful military complex. And yet Hamburg's mayor, Johann Heinrich Burchard, echoed the feelings of many when he described this new wonder as “above all … the product of a flourishing, self-conscious German middle class.” Although extolled as a symbol of German unity, Social Democrats denounced the modern leviathan as an expression of class inequality and lamented that ten men were killed and one hundred injured while constructing it. With this in mind, how could Germany be proud of what it had achieved?
Full Information, Well-Being, and Reasonable Desires
Authors: SHEMMER YONATAN
Published: May 2011

According to Railton:x is good for me iff my Fully Informed Self (FIS) while contemplating my situation would want me to want x.I offer four interpretations of this view. The first three are inadequate. Their inadequacy rests on the following two facts: (a) my FIS cannot want me to want what would be irrational for me to want, (b) when contemplating what is rational for me to want we must specify a particular way in which I could rationally acquire the recommended desire. As a result, what my FIS could reasonably want me to want is limited by what information my FIS could reliably convey to me. And therefore what my FIS could reasonably want me to want cannot be grounded in changes in desires that my FIS cannot publicly justify. The fourth interpretation limits the scope of what my FIS could want me to want in a way that avoids these problems, but conflicts with standard intuitions about what is a non-moral good.
Single coronary artery giving rise to an intraseptal left coronary artery in a patient presenting with neurocardiogenic syncope
Authors: Johnson Jonathan N. , Bonnichsen Crystal R. , Julsrud Paul R. , Burkhart Harold M. , Hagler Donald J.
Published: May 2011

Background

Syncope occurs frequently in adolescents, and is often benign. Potential worrisome syncopal events include those occurring with exertion, concurrent chest pain, dyspnoea or palpitations, and those with focal or diffuse neurologic changes.

Case

A 16-year-old female was referred to our institution for a history of exercise-induced spells. She was diagnosed since the age of 2 years with neurocardiogenic syncope and postural orthostatic tachycardia syndrome. She had been evaluated at multiple institutions, and was followed by pediatric neurology for a diagnosis of migraines. Owing to recurrent worsening symptoms and a syncopal episode requiring resuscitation, an echocardiogram was performed. The right coronary was normal, but the left coronary artery ostium could not be identified well. Doppler patterns were suspicious of an abnormal left coronary artery, and computed tomography angiography was performed. This revealed a single coronary artery arising from the right aortic sinus, with the left coronary artery arising from the proximal coronary trunk and coursing through the infundibular septum. This was surgically treated utilising a left internal mammary artery bypass graft to the left anterior descending coronary artery. A year later, she has not experienced any recurrence of syncope, and has returned to athletic activity.

Conclusion

This case highlights the index of suspicion that must be present when evaluating any patient with syncope, both clinically and via echocardiography. A computed tomography angiogram is indicated for better evaluation of coronary artery anatomy when an anomalous coronary cannot be ruled out by echocardiography.
Bridging the Micro-to-Macro Gap: A New Application for Micro X-Ray Fluorescence
Authors: Davis Jeffrey M. , Newbury Dale E. , Fahey Albert , Ritchie Nicholas W.M. , Vicenzi Edward , Bentz Dale
Published: May 2011

X-ray elemental mapping and X-ray spectrum imaging are powerful microanalytical tools. However, their scope is often limited spatially by the raster area of a scanning electron microscope or microprobe. Limited sampling size becomes a significant issue when large area (>10 cm2), heterogeneous materials such as concrete samples or others must be examined. In such specimens, macro-scale structures, inclusions, and concentration gradients are often of interest, yet microbeam methods are insufficient or at least inefficient for analyzing them. Such requirements largely exclude the samples of interest presented in this article from electron probe microanalysis. Micro X-ray fluorescence–X-ray spectrum imaging (μXRF-XSI) provides a solution to the problem of macro-scale X-ray imaging through an X-ray excitation source, which can be used to analyze a variety of large specimens without many of the limitations found in electron-excitation sources. Using a mid-sized beam coupled with an X-ray excitation source has a number of advantages, such as the ability to work at atmospheric pressure and lower limits of detection owing to the absence of electron-induced bremsstrahlung. μXRF-XSI also acts as a complement, where applicable, to electron microbeam X-ray output, highlighting areas of interest for follow-up microanalysis at a finer length scale.
Temporally resolved ion velocity distribution measurements in a radio-frequency plasma sheath
Authors: Jacobs B. , Gekelman W. , Pribyl P. , Barnes M.
Published: May 2011

The ion velocity distribution function (IVDF) above and within a radio-frequency (RF) biased plasma sheath is studied experimentally with a pulsed laser-induced fluorescence diagnostic in an industrial plasma etch tool. Temporally resolved measurements taken at eight different phases of the 2.2 MHz bias waveform show that the ion dynamics vary dramatically throughout the RF cycle (the ratio of the average ion transit time through the sheath to the RF period is τion/τRF = 0.3). The position of the presheath/sheath edge is constant throughout the RF cycle and the time-averaged ion flux is conserved within the sheath region. The characteristic bimodal structure of the time-averaged ion distributions found in previous experiments is observed to arise from the time-dependent ion dynamics, in accord with existing theory. The large temporal variation of the IVDF has implications for the plasma chemistry and etching quality.
Octonionic Maxwell's equations for bi-isotropic media
Authors: Tanışlı M. , Kansu M. E.
Published: May 2011

In this study, octonions with eight dimensions and their algebra, which are both noncommutative and nonassociative, are presented. Moreover, the general properties of complex octonions with 16 dimensions and the products of basis are defined by using Cayley–Dickson multiplication rules. Maxwell's equations are taken into consideration when it comes to bi-isotropic media in which the electric and magnetic fields are coupled by means of bi-isotropic constitutive relations. The Drude–Born–Fedorov constitutive relations defined with the complex representations of electric and magnetic fields are used for all calculations. In the next stage, the complex octonionic differential operator is introduced and the octonionic field and source equations are defined for bi-isotropic media. As a result, Maxwell's equations for bi-isotropic media, which are fundamental features that serve as the groundwork for electromagnetism, all of them as being unique, more compact, and a convenient form with magnetic monopole.
Ferromagnetic nanocylinders electrodeposited into nanoporous alumina template: A magnetometry and Brillouin light scattering study
Authors: Chérif S. M. , Roussigné Y. , Stashkevich A. A. , Darques M. , Bouziane K. , Piraux L.
Published: May 2011

The static magnetization experimental behavior of cobalt (Co), Permalloy (Py), and nickel (Ni) nanocylinders is obtained from vibrating sample magnetometry while the dynamic behavior for the Co and Py ones is analyzed by means of Brillouin light scattering spectroscopy. Assuming the presence at remanence of two populations of cylinders with up and down magnetizations and including the dipolar coupling between the cylinders, a single analytical model based on a mean-field approach allowed us to satisfactorily analyze both series of experimental results. The model requires three physical parameters, allowing us to derive the in-plane saturation field, the eigenfrequency in the absence of applied field, and the eigenfrequency at the in-plane saturation field; these parameters enable us to adjust the whole variation of the eigenfrequency versus the applied field. Moreover, the effect of the magnetocrystalline anisotropy on the softening of the frequency in the nonsaturated state is clearly evidenced: it is more pronounced when the magnetocrystalline anisotropy is not vanishing and adds to the shape anisotropy (Co c-axis parallel to the cylinder axis); the softening being weak in the other cases (Co c-axis perpendicular to the cylinder axis or Permalloy).
Vortex penetration and flux relaxation with arbitrary initial conditions in non-ideal and ideal superconductors
Authors: Ma Rongchao
Published: May 2011

Vortex penetration and flux relaxation phenomena carry information about the pinning ability, and consequently current-carrying ability, of a type-II superconductor. However, the theoretical descriptions of these phenomena are currently limited to the cases with special initial conditions. A generalization to the recently developed infinite series models is presented here. It is shown that one can convert a vortex penetration process with a nonzero initial internal field into a process with a zero initial internal field by introducing some time parameters. Similarly, one can also convert a flux relaxation process starting with an arbitrary internal field into a process starting with a melting internal field by introducing a virtual time interval. Therefore, one can predict the melting internal field (or critical current density) from a flux relaxation process starting with a lower internal field. Finally, I show that the vortex penetration process in an ideal superconductor is strongly time dependent because of the surface barrier and internal field repulsive force. But the flux relaxation process does not occur in the ideal superconductor.
Investigation of efficiency droop for InGaN-based UV light-emitting diodes with InAlGaN barrier
Authors: Tu Po-Min , Chang Chun-Yen , Huang Shih-Cheng , Chiu Ching-Hsueh , Chang Jet-Rung , Chang Wei-Ting , Wuu Dong-Sing , Zan Hsiao-Wen , Lin Chien-Chung , Kuo Hao-Chung , Hsu Chih-Peng
Published: May 2011

The efficiency droop in InGaN-based UV light emitting device (LED) with AlGaN and InAlGaN barrier is investigated. Electroluminescence results indicate that the light performance of quaternary LEDs can be enhanced by 25% and 55% at 350 mA and 1000 mA, respectively. Furthermore, simulations show that quaternary LEDs exhibit 62% higher radiative recombination rate and low efficiency degradation of 13% at a high injection current. We attribute this improvement to increasing of carrier concentration and uniform redistribution of carriers.