bluuebunny/crossref_metadata_2025 huggingface dataset:
Prospective respiratory motion correction for coronary MR angiography using a 2D image navigator
Authors: Henningsson Markus , Smink Jouke , Razavi Reza , Botnar René M.
Published: April 2012

Respiratory motion remains the major impediment in a substantial amount of patients undergoing coronary magnetic resonance angiography. Motion correction in coronary magnetic resonance angiography is typically performed with a diaphragmatic 1D navigator (1Dnav) assuming a constant linear relationship between diaphragmatic and cardiac respiratory motion. In this work, a novel 2D navigator (2Dnav) is proposed, which prospectively corrects for translational motion in foot–head and left–right direction. First, 1Dnav‐ and 2Dnav‐based motion correction are compared in 2D real time imaging experiments, by evaluating the residual respiratory motion in 10 healthy subjects as well as in a moving vessel phantom. Subsequently, 1Dnav and 2Dnav corrected high‐resolution 3D coronary MR angiograms were acquired, and both objective and subjective image quality were assessed. For a gating window of 10 mm, 1Dnav and 2Dnav performed equally well; however, without any respiratory gating, the 1Dnav had a lower visual score for all coronary arteries compared with 10 mm gating, whereas the 2Dnav without gating performed similar to 1Dnav with 10 mm gating. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Square regularization matrices for large linear discrete ill‐posed problems
Authors: Donatelli Marco , Neuman Arthur , Reichel Lothar
Published: April 2012

Large linear discrete ill‐posed problems with contaminated data are often solved with the aid of Tikhonov regularization. Commonly used regularization matrices are finite difference approximations of a suitable derivative and are rectangular. This paper discusses the design of square regularization matrices that can be used in iterative methods based on the Arnoldi process for large‐scale Tikhonov regularization problems. Copyright © 2012 John Wiley & Sons, Ltd.
Anatomical and Biomechanical Aspects of the Horse Spine: The Interpretation of Vertebral Fusion in a Medieval Horse from Wroclaw (Poland)
Authors: Janeczek M. , Chrószcz A. , Onar V. , Henklewski R. , Piekalski J. , Duma P. , Czerski A. , Całkosiński I.
Published: April 2012

The investigation were carried out on the medieval horses thoracic and lumbar spine excavated between 2009‐2011 by the Institute of Archaeology, University of Wroclaw at New Market Square in Wroclaw (Wratislavia, Breslau), capital city of the Polish province of Lower Silesia. The pathological changes, like: ankylosis of the zygapophyses, fusion of the vertebral bodies and arches and the interspinal space calcification were observed. The X‐ray examination was done. During medieval artefact interpretation the biomechanical aspect of horse's locomotor system was taken into consideration. The archaeozoological material was compared with modern horse's spine (with similar pathological changes and known history of disease). The analysis proved, that the observed osseous reaction was a result of the long‐lasting inflammation. Such a disease appearance accompanies chronic inflammatory state of errector muscles of the spine. It is typical for those horses utilised for the saddle. Copyright © 2012 John Wiley & Sons, Ltd.
Community acceptance of recycled water: can we inoculate the public against scare campaigns?
Authors: Kemp Byron , Randle Melanie , Hurlimann Anna , Dolnicar Sara
Published: April 2012

Without improved water resource management, it is predicted that water shortages will affect two‐thirds of humanity by 2025. One solution that has traditionally faced fierce public resistance is recycled waste water. This study investigates the extent to which public communication strategies can influence community acceptance of recycled water, using the framework of Inoculation Theory. A four‐phase experimental design was conducted. Participants completed an initial questionnaire and were then randomly assigned to a control group, a manipulation check group or a treatment group. A final follow‐up survey measured changes in the dependent variable: stated likelihood of using recycled water for different uses. Results indicate that communication strategies based on Inoculation Theory are limited in their effectiveness for this product category. Findings do, however, identify a clear recency effect, indicating that continuous public communications are key to ensuring that community scare campaigns do not prevent implementation of water augmentation projects. This study differs from previous applications of Inoculation Theory because of the challenges associated with marketing a monopoly commodity, which is a necessity to support life. This empirical study uses fictional marketing stimuli to test the theory in a context, which is growing in global importance. Copyright © 2012 John Wiley & Sons, Ltd.
Exploring factors influencing non‐attendance at the diabetes clinic and service improvement strategies from patients' perspectives
Authors: Akhter Kalsoom , Dockray Samantha , Simmons David
Published: April 2012

A significant number of people with type 1 diabetes do not attend their clinic appointments. This study investigated the reasons underlying this decision and explored possible service improvement strategies.

This was a cross‐sectional telephone survey among all patients with type 1 diabetes missing at least one appointment at a diabetes clinic between 1 October 2009 and 30 September 2010. Patients were asked two questions: why they did not attend the appointment and how attendance could be improved.

The initial ‘did not attend’ (DNA) rate for all appointments was 17.6% (808/4595 appointments). Of these, the largest number were missed by patients (n=252) with type 1 diabetes. After excluding 79 patients no longer under the service, 126/173 (72.8%) were able to be contacted and answered the questions. Forgetting the appointment was the most frequent response (34.9%). Many patients advised not to send appointment reminder letters too far ahead of appointments (12.7%, 16) and to send a text message reminder (26.2%, 33) two weeks before the appointment.

The findings suggest that there is a role for improving the administrative approach to patients' appointments, reminding patients in advance and improving communication between hospital staff and patients. Copyright © 2012 John Wiley & Sons.
Increasing scientific standards, independence and transparency in post‐authorisation studies: the role of the European Network of Centres for Pharmacoepidemiology and Pharmacovigilance
Authors: Blake Kevin V , deVries Corinne S , Arlett Peter , Kurz Xavier , Fitt Henry ,   for the European Network of Centres for Pharmacoepidemiology Pharmacovigilance
Published: April 2012

Purpose

The European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (ENCePP), an initiative coordinated by the European Medicines Agency, aims to build capacity for and increase trust in post‐authorisation studies to further support medicine decision making.

Methods

ENCePP seeks to promote and support high standards throughout the post‐authorisation research process based on robust methodologies, transparency and scientific independence.

Results

ENCePP provides a point of access to researchers for industry, academia and regulatory authorities seeking collaboration for the conduct of post‐authorisation studies. As of 30 November 2011, the network consisted of 98 research centres, 13 networks and 18 data sources, mostly academic and publicly funded institutions but also data source providers and contract research organisations with expertise in the conduct of post‐authorisation studies. All are listed in the free, public and fully searchable electronic Database of Research Resources. A guide and a checklist on methodological standards have been published; the concept of an ‘ENCePP study’, including a Code of Conduct, introduced; and an electronic register of studies have been launched.

Conclusion

It is envisaged that application of the ENCePP study concept will result in an increase in trust in post‐authorisation studies of medicines. The register of studies will allow for ready access to study protocols and results, thereby enhancing transparency and facilitating review. Through the network, standards, transparency and clarity of relationships, ENCePP is expected to add to the European Union capacity to conduct robust post‐authorisation studies, thereby benefiting public health. Copyright © 2012 John Wiley & Sons, Ltd.
Rheological and electrical percolation thresholds of carbon nanotube/polymer nanocomposites
Authors: Penu Christian , Hu Guo‐Hua , Fernandez Amaia , Marchal Philippe , Choplin Lionel
Published: April 2012

Percolation thresholds of multiwalled carbon nanotube/polystyrene (MWCNT/PS) nanocomposites (NC) were determined by rheology and electrical conductivity. The percolation threshold found by electrical conductivity was 0.5% carbon nanotubes (CNT) and that by mechanical spectroscopy and relaxation measurements was 0.9% CNT. These results together with those reported in the literature show several types of percolation thresholds, depending on the average filler–filler (CNT and/or aggregates) distance in a polymer matrix. A distance close to polymer gyration radius corresponds to a “soft” rheological threshold (PC rheosoft). Close contacts between fillers giving rise to a conductive path corresponds to an electrical threshold (PC elec). At high filler concentration, fillers form a network, corresponding to a “rigid” rheological threshold (PC rheorigid). These thresholds depend on the filler content and follow the order:PC elecsoft<PC elec<PC rheorigid. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Synthesis of a novel flame retardant containing phosphorus and sulfur and its application in polycarbonate
Authors: Zhao Wei , Li Bin , Xu Miaojun , Zhang Lili , Liu Fangmeng , Guan Limin
Published: April 2012

A novel flame retardant containing phosphorus and sulfur, bis(2‐tienyl)phenylphosphine (BTPP) was synthesized and characterized with Fourier transform infrared spectroscopy, 1H, 13C, and 31P nuclear magnetic resonance. BTPP was used to impart flame retardancy to polycarbonate (PC). Combustion behaviors and thermal degradation properties of PC/BTPP system were assayed by limiting oxygen index (LOI), vertical burning test (UL‐94), cone calorimeter test, and thermogravimetric analysis. PC/3 wt% BTPP passed UL‐94 V‐0 rating with 3.0 mm samples and the LOI value was 36.5%. PC/6 wt% BTPP passed UL‐94 V‐0 rating with 1.6 mm samples and the LOI value was 38.5%. Scanning electron microscopy revealed that char properties had direct effects on the flame retardancy. Mechanical properties and water resistance of PC/BTPP system were also examined. After water resistance test, PC/3 wt% BTPP with 3.0 mm samples and PC/6 wt% BTPP with 1.6 mm samples kept V‐0 rating and mass loss were only 0.2%. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
A new size‐independent score for pairwise protein structure alignment and its application to structure classification and nucleic‐acid binding prediction
Authors: Yang Yuedong , Zhan Jian , Zhao Huiying , Zhou Yaoqi
Published: April 2012

A structure alignment program aligns two structures by optimizing a scoring function that measures structural similarity. It is highly desirable that such scoring function is independent of the sizes of proteins in comparison so that the significance of alignment across different sizes of the protein regions aligned is comparable. Here, we developed a new score called SP‐score that fixes the cutoff distance at 4 Å and removed the size dependence using a normalization prefactor. We further built a program called SPalign that optimizes SP‐score for structure alignment. SPalign was applied to recognize proteins within the same structure fold and having the same function of DNA or RNA binding. For fold discrimination, SPalign improves sensitivity over TMalign for the chain‐level comparison by 12% and over DALI for the domain‐level comparison by 13% at the same specificity of 99.6%. The difference between TMalign and SPalign at the chain level is due to the inability of TMalign to detect single domain similarity between multidomain proteins. For recognizing nucleic acid binding proteins, SPalign consistently improves over TMalign by 12% and DALI by 31% in average value of Mathews correlation coefficients for four datasets. SPalign with default setting is 14% faster than TMalign. SPalign is expected to be useful for function prediction and comparing structures with or without domains defined. The source code for SPalign and the server are available at http://sparks.informatics.iupui.edu. Proteins 2012;. © 2012 Wiley Periodicals, Inc.
Biaxially textured copper–iron alloys for coated conductors
Authors: Gallistl Bernhard , Kirchschlager Raimund , Hassel Achim Walter
Published: April 2012

Two copper based biaxially textured alloys containing 0.37 and 0.91 wt.%‐Fe have been investigated for the use as substrate material for coated conductors. Average full width at half maximum (FWHM) values of 7.3° (CuFe0.37) and 6.8° (CuFe0.91) for in‐plane alignment and 7.2° (CuFe0.37, CuFe0.91) for out‐of‐plane are achieved. Ultimate tensile strength for the two alloys is found to be much higher compared to the values for Cu and CuFe2.35. Hysteresis losses are dramatically reduced compared to other available substrate materials. Magnetisation data for both alloys obtained at 5 K show an anticipated saturation magnetisation (Ms) <0.35 µWb m kg−1, which is less than 1% of pure Ni.

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Selective dissolution in AlFeNb alloys
Authors: Drensler Stefanie , Mardare Cezarina Cela , Milenkovic Srdjan , Hassel Achim Walter
Published: April 2012

Three different AlFeNb alloys of various compositions were prepared by arc melting. X‐ray diffraction (XRD) investigation of the melted samples proved the presence of two phases identified as a bcc α(Fe,Al) solid solution and a hexagonal C14 (Fe,Al)2Nb Laves phase. Subsequent electrochemical treatment allowed for a selective dealloying of the α(Fe,Al) or respective FeAl phase and resulted in releasing differently microstructured surfaces. These structures ranged from regular lamellar structures towards branched, fibrous structures. Scanning electron microscope (SEM) characterisation along with a local energy dispersive X‐ray spectroscopic (EDX) analysis of the samples and atomic absorption spectrometry (AAS) analysis of the electrolyte revealed a preferential Fe dissolution and the passive nature of the Nb. The results demonstrate that the phases present in the alloys strongly depend on the production and heat treatment history of the sample.

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SEM micrograph of (A) Fe‐15Al‐10Nb and (B) Fe‐26Al‐4Nb after anodisation in 0.4 M borate buffer.
Structural and magnetic properties of Co2MnSi thin films
Authors: Belmeguenai M. , Zighem F. , Faurie D. , Tuzcuoglu H. , Chérif S.‐M. , Moch P. , Westerholt K. , Seiler W.
Published: April 2012

Co2MnSi (CMS) films of different thicknesses (20, 50, and 100 nm) were grown by radio frequency (RF) sputtering on a‐plane sapphire substrates. Our X‐rays diffraction (XRD) study shows that, in all the samples, the cubic 〈110〉 CMS axis is normal to the substrate and that six well defined preferential in‐plane orientations are present. Static and dynamic magnetic properties were investigated using vibrating sample magnetometry (VSM) and microstrip line ferromagnetic resonance (MS‐FMR), respectively. From the resonance measurements versus the direction and the amplitude of an applied magnetic field, most of the magnetic parameters are derived, i.e.: the magnetization, the gyromagnetic factor, the exchange stiffness coefficient, and the magnetic anisotropy terms. The in‐plane anisotropy results from the superposition of two terms showing a twofold and a fourfold symmetry, respectively. The observed behavior of the hysteresis loops is in agreement with this complex form of the in‐plane anisotropy.
Secondary electron emission yield (SEY) in amorphous and graphitic carbon films prepared by PLD
Authors: Alberti M. , Ayouchi R. , Bhattacharyya S. R. , Bundaleski N. , Moutinho A. , Teodoro O. , Aguilera L. , Taborelli M. , Schwarz R.
Published: April 2012

High secondary emission yield (SEY), and the subsequent build‐up of a secondary electron cloud, may severely limit the stability of high‐intensity particle beams inside particle accelerators. One of the best candidates of beam pipe coating for reduced SEY has been amorphous carbon (a‐C) produced by direct current (D.C.) magnetron sputtering. Here we used pulsed laser deposition (PLD), to prepare a‐C films from a pure carbon target at substrate temperatures ranging from 300 K to 773 K. The ablating laser was a Nd:YAG system operating at 1064 nm wavelength. With increasing temperature the optical band gap dropped from about 2.1 eV to 1.0 eV. This trend indicates transition from predominantly a‐C films to films with more graphitic content, which was also confirmed by Raman measurements. SEY spectra were taken upto 1732 eV of primary electron energy. The maximum SEY value decreased from 1.9 in a‐C films down to 1.4 in highly graphitic films deposited at higher temperatures (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication and properties of nanocrystalline Zn‐Ir‐O thin films
Authors: Grochowski Jakub , Kamińska Eliana , Piotrowska Anna , Dynowska Elżbieta , Dłużewski Piotr , Dyczewski Jan , Szczepańska Alicja , Kaźmierczak Piotr
Published: April 2012

New p‐type semiconducting ZnIrSiO thin films were fabricated using reactive magnetron RF sputtering from ZnIrSi target. Their transport properties were: resistivity ρ=0.6 Ωcm, hole concentration p=5x1018 cm‐3 and mobility μ=2 cm2/Vs. Optical transmission in the visible wavelength region is 70% and band gap width Eg=3.17 eV. Films are XRD amorphous. HRTEM analysis revealed that ZnIrSiO films were composed of 1‐3 nm in diameter nanograins of Ir3Si and ZnIr2O4 embedded in an amorphous SiO2 matrix. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phenolic‐Linked Biochemical Rationale for the Anti‐Diabetic Properties of Swertia chirayita (Roxb. ex Flem.) Karst.
Authors: Phoboo Susanna , Pinto Marcia Da Silva , Barbosa Ana Cristina Lopes , Sarkar Dipayan , Bhowmik Prasanta C , Jha Pramod Kumar , Shetty Kalidas
Published: April 2012

The crude extract of Swertia chirayita, an important medicinal plant of Nepal, is locally used for many diseases including type 2 diabetes. In this study, crude aqueous and 12% ethanol solution extracts of S. chirayita collected from nine districts of Nepal were analyzed for anti‐diabetic‐linked anti‐hyperglycemia potential using in vitro biochemical assays. There was moderate‐to‐high positive correlation between antioxidant activity and total phenolic content of both extracts and moderate‐to‐high α‐glucosidase inhibitory activity. Although the anti‐diabetic property of S. chirayita is mainly attributed to the phytochemical swerchirin present in its hexane fraction, we propose that the crude extract of this plant used in local healing also has anti‐hyperglycemia potential. The crude extracts indicated the presence of three main phytochemicals mainly mangiferin, swertiamarin, and amarogentin and their derivatives. Among the standard compounds (mangiferin, swertiamarin, and amarogentin), mangiferin showed α‐glucosidase and 2,2‐diphenyl‐1‐picrylhydrazyl radical inhibitory activity indicating anti‐hyperglycemia potential. Copyright © 2012 John Wiley & Sons, Ltd.
The February 2010 Arctic Oscillation Index and its stratospheric connection
Authors: Ripesi P. , Ciciulla F. , Maimone F. , Pelino V.
Published: April 2012

The atmospheric dynamics during the occurrence of the extreme negative value of the Arctic Oscillation Index in February 2010 are investigated using meteorological fields from ERA‐Interim and ERA‐40 reanalysis data. The study focuses on the possible causes of this anomalous value, finding that it was forced by a geopotential anomaly that propagated downward from the stratosphere to the troposphere in association with a major sudden stratospheric warming event which occurred at the end of January. An analysis of the dynamics of this warming is also developed, together with a comparison with past similar events. Synoptic and spectral properties of the geopotential fields are analyzed, and the time series of the ‘Baroclinic Activity Index’ are computed, finding an abrupt increase of the middle latitude baroclinic activity immediately after the central date of the warming event. A possible interpretation of this feature is proposed. Copyright © 2012 Royal Meteorological Society
Nonorthogonal orbitals; the Hartree–Fock–Heitler–London method and preliminary applications
Authors: Clementi Enrico , Corongiu Giorgina
Published: April 2012

Since the early days of quantum chemical computations, the determinantal wave function can be constructed either with orthogonal or nonorthogonal one electron functions (the orbitals). The two classical quantum mechanical methods, the Hartree–Fock (HF), and the Heitler–London (HL) are examples of the use of orthogonal, and nonorthogonal orbitals, respectively. Both models are approximations yielding approximately half of the experimental binding energy, due to the correlation error. Very extended expansions (with many thousand determinants) recover the error. The two methods have been recently merged into the Hartree–Fock–Heitler–London method (HF–HL), which systematically ensures correct molecular dissociation and a binding energy generally more correct than that obtained with the two parent models. Relatively short expansions of HL configurations yield correct binding energies, at the expense, however, of a high computational time in the optimization of the orbital expansion coefficients. In the HF–HL model, the inner shell electronic correlation is computed with a Coulomb hole functional. We compare computations at the HF, HL, and HF–HL levels, and for the latter, we consider relatively short expansions leading to reasonable binding energies. The computations compare the ground‐state potential energies of the hydrides and homopolar diatomic molecules of the first and second period of the atomic table, a few excited states, and small polyatomic molecules like H2O, C2H2, and HCN. © 2012 Wiley Periodicals, Inc.
Electrostatic potentials and polarization effects in proton‐molecule interactions by means of multipoles from the quantum theory of atoms in molecules
Authors: Terrabuio Luiz Alberto , Haiduke Roberto L. A.
Published: April 2012

Some atomic multipoles (charges, dipoles and quadrupoles) from the Quantum Theory of Atoms in Molecules (QTAIM) and CHELPG charges are used to investigate interactions between a proton and a molecule (F2, Cl2, BF, AlF, BeO, MgO, LiH, H2CO, NH3, PH3, BF3, and CO2). Calculations were done at the B3LYP/6‐311G(3d,3p) level. The main aspect of this work is the investigation of polarization effects over electrostatic potentials and atomic multipoles along a medium to long range of interaction distances. Large electronic charge fluxes and polarization changes are induced by a proton mainly when this positive particle approaches the least electronegative atom of diatomic heteronuclear molecules. The search for simple equations to describe polarization on electrostatic potentials from QTAIM quantities resulted in linear relations withr(ris the interaction distance) for many cases. Moreover, the contribution from atomic dipoles to these potentials is usually the most affected contribution by polarization what reinforces the need for these dipoles to a minimal description of purely electrostatic interactions. Finally, CHELPG charges provide a description of polarization effects on electrostatic potentials that is in disagreement with physical arguments for certain of these molecules. © 2012 Wiley Periodicals, Inc.
ID‐CUBE direct analysis in real time high‐resolution mass spectrometry and its capabilities in the identification of phenolic components from the green leaves of Bergenia crassifolia L.
Authors: Chernetsova Elena S. , Crawford Elizabeth A. , Shikov Alexander N. , Pozharitskaya Olga N. , Makarov Valery G. , Morlock Gertrud E.
Published: April 2012

RATIONALE

Bergenia crassifolia is a plant widely used in herbal medicine. Its chemical composition has been little studied, and no studies using high‐resolution mass spectrometry (HRMS) have been performed. Its phenolic components are of particular interest, due to the interest in such compounds in medicine and cosmetics. The ID‐CUBE, a simplified Direct Analysis in Real Time (DART) ion source, suitable for the fast MS analysis of liquids without complex sample preparation, offers a new method of studying extracts of such plant. Coupling the ID‐CUBE with a high‐resolution mass spectrometer can provide identification of extract components.

METHODS

Mass spectral conditions were optimized for model solutions of the flavonoid naringenin and used for the identification of phenolic compounds in green leaves extracts of Bergenia crassifolia. OpenSpot sample cards with a metal grid surface were used for sample introduction into the ID‐CUBE ion source on an Obitrap mass spectrometer. The samples were applied as 5‐μL aliquots of the extract onto the metal grid of the card. Sample ionization was stimulated in the ion source within 20 s by applying an electric current to the metal grid to thermally desorb the analytes into the gas flow of metastable helium atoms from the ID‐CUBE.

RESULTS

Elemental compositions were assigned to abundant ions in the mass spectra of the extracts. The major phenolic components were confirmed by their [M–H]– ions. Thirty‐six other marker ions were found, and elemental compositions were suggested for 30% of them, based on a search for compounds found in herbal extracts.

CONCLUSIONS

The ID‐CUBE–Orbitrap MS coupling allowed the rapid accurate mass determination of the phenolic components (and other compounds) in herbal extracts. Higher confidence in component identification could be provided by using additional structural elucidation methods, including tandem mass spectrometry (MS/MS), and this will be the focus of future studies. Copyright © 2012 John Wiley & Sons, Ltd.
How Shape Influences Uptake: Interactions of Anisotropic Polymer Nanoparticles and Human Mesenchymal Stem Cells
Authors: Florez Laura , Herrmann Christine , Cramer Jens M. , Hauser Christoph P. , Koynov Kaloian , Landfester Katharina , Crespy Daniel , Mailänder Volker
Published: April 2012

Among several nanoparticle properties, shape is important for their interaction with cells and, therefore, relevant for uptake studies and applications. In order to further investigate such characteristics, fluorescently labeled spherical polymer nanoparticles are synthesized by free‐radical polymerization via the miniemulsion process. The spherical nanoparticles are subsequently submitted to controlled mechanical deformation to yield quasi‐ellipsoidal polymeric nanoparticles with different aspect ratios. The uptake behaviors of spherical and non‐spherical particles with equal volume are investigated qualitatively and quantitatively by electron microscopy, confocal laser scanning microscopy, and flow cytometry measurements. Non‐spherical particles show fewer uptake by cells than their spherical counterparts with a negative correlation between aspect ratio and uptake rate. This is attributed to the larger average curvature radius of adsorbed non‐spherical particles experienced by the cells.
STT and DTT Diagrams of Austenitic Cr–Mn–Ni As‐Cast Steels and Crucial Thermodynamic Aspects of γ → α′ Transformation
Authors: Kovalev Alexander , Jahn Andreas , Weiß Andreas , Wolf Steffen , Scheller Piotr R.
Published: April 2012

The mechanical behavior and microstructure evolution during deformation of novel austenitic Cr–Mn–Ni as‐cast steels with varied Ni content were investigated at various temperatures using static tensile tests, optical microscopy, and the magnetic scale for the detection of ferromagnetic phase fraction. To summarize all knowledge about the deformation‐induced processes, the STT and DTT diagrams were developed for Cr–Mn–Ni steels. The diagrams illustrate the different deformation mechanisms depending on temperature and tension load, and quantify the elongation of the deformation mechanisms. The deformation‐induced ε‐ and α' martensite formation and twinning – the TRIP and TWIP effects – occur in the Cr–Mn–Ni steels depending on the chemical composition and temperature. The differences of deformation‐induced processes depend on thermodynamics and are confirmed by thermodynamic calculations. The nucleation threshold of γ → α′ transformation was determined for the investigated Cr–Mn–Ni steels.
SEM Investigation of High‐Alloyed Austenitic Stainless Cast Steels With Varying Austenite Stability at Room Temperature and 100°C
Authors: Biermann Horst , Solarek Johannes , Weidner Anja
Published: April 2012

The deformation mechanisms of high‐alloyed cast austenitic steels with 16% of chromium, 6% of manganese, and a nickel content of 3–9% were investigated by in situ and ex situ scanning electron microscopy. The austenite stability and the stacking fault energy were influenced by variation of the chemical composition as well as by changing deformation temperature (room temperature; RT and 100°C). The study shows that both an increase in austenite stability and stacking fault energy yield a significant change in the deformation mechanisms. Both increase of nickel content and increase in deformation temperature reduce the intensity of the martensitic phase transformation. Thus, the steel with low nickel content shows at RT pronounced formation of α′‐martensite. The steel with the highest nickel content, however, shows pronounced twinning.
Suppression of Fusarium graminearium growth by differently structured starch types
Authors: Svensson Jan T. , Olas Justyna J. , Skibior Renate , Giese Henriette , Blennow Andreas
Published: April 2012

We investigated the growth behavior and amylolytic enzymes of Fusarium graminearum cultivated on different types of native starch granules including barley (A‐type crystalline polymorph), potato and Curcuma zedoaria (B‐type crystalline polymorph), cassava (C‐type crystalline polymorph), and high AM maize (A + Vh‐type crystalline polymorphs). F. graminearum grew poorly on B‐type starches and the accumulation of biomass was similar to that obtained for fungi cultivated under carbohydrate starvation conditions. In comparison, three‐ to fivefold higher accumulation of fungal biomass was observed for growth on the A‐, C‐ and A + Vh‐type starches. Fungal glucoamylase and α‐amylase activity increased over time in the presence of native starch granules. Interestingly, resistant B‐type starches induced the highest amylolytic activity indicating that F. graminearum interacts with B‐type granules although only limited degradation occur. Starch degradation products maltose and malto‐oligosacharides was found to increase glucoamylase and α‐amylase activity, whereas glucose acted as a catabolite repressor.
Study on properties of Cyperus esculentus starch grown in Xinjiang, China
Authors: Jing Siqun , Yan Xiaoxin , Ouyang Weiqi , Xiang Hengxu , Ren Zhiyan
Published: April 2012

The chemical composition, morphological characteristics, and pasting properties of Cyperus esculentus starch (CES) grown in Xinjiang, China, were investigated and compared with those of potato starch (PS). The amylopectin (AP) content in CES was measured as of 83.82%. Most of the starch granules of Cyperus esculentus (CE) were round or elliptical while the granule diameter ranged from 3.41 to 12.12 µm with an average value of 8.60 µm, and had a typical polarization cross. The X‐ray diffraction (XRD) data showed that CES was of A‐type crystals. The peak viscosity value of CES paste was much lower than that of PS, and the freeze–thaw stability of CES paste was slightly higher than that of PS, but its light transmittance was lower.
Synthesis and characterization of hydrophobically modified starch by ring opening polymerization using imidazole as catalyst
Authors: Zerroukhi Amar , Jeanmaire Thomas , Raveyre Claude , Ainser Auder
Published: April 2012

This paper reports on the synthesis of polyester‐grafted starch (starch‐g‐PCL) by in situ ring‐opening polymerization (ROP) of ε‐caprolactone (ε‐CL) catalyzed by a metal free organic catalyst (imidazole). This reaction has been carried out in bulk, without solvent. The structure of starch‐g‐PCL was characterized by IR, NMR, DSC, and SEM. A moisture sorption isotherm of modified starch revealed a more hydrophobic material. A water contact angle measurement also confirmed the hydrophobic character of starch‐g‐PCL. As expected, this chemical modification reduced the diffusion coefficient of water. The use of an organic catalyst instead of the traditional organometallic catalyst offers an interesting alternative for producing moisture tolerant thermoplastic starch‐based materials.
Evidence for the improvement of thermostability of the maltogenic α‐amylase of Aspergillus niger by negative pressure
Authors: Herale Rajalakshmi , Sukumaran Umesh‐Kumar , Kadeppagari Ravi‐Kumar
Published: April 2012

Thermostability of the enzymes is influenced by the different parameters and pressure also influences the biological activity of the enzymes. Recently reported maltogenic α‐amylase from Aspergillus niger acts optimally on starch at 40°C and it was unstable above 40°C at atmospheric pressure. Calcium could stabilize the maltogenic α‐amylase activity up to 50°C at atmospheric pressure. But, at negative pressure (−200 mbar) enzyme was stable at temperatures higher than 50°C either in the presence or absence of the substrate, starch making it adoptable for starch processing. Enzyme showed higher affinity to the starch at negative pressure compared to the atmospheric pressure and change in the surface roughness of the enzyme is almost similar to the native state at 70°C and negative pressure. These results suggest that thermolabile enzymes can be used at negative pressures for industrial applications.
Facile preparation of sago starch esters using full factorial design of experiment
Authors: Soetaredjo Felycia Edi , Ismadji Suryadi , Huynh Lien Huong , Kasim Novy S. , Tran‐Thi Ngoc Yen , Ayucitra Aning , Ju Yi‐Hsu
Published: April 2012

A facile solvent‐free method to acetylate sago starch (Metroxylon sagu) is reported. Microwave (100 W) was used as the heating source and the heating time was varied from 2 to 10 min with the temperature of acetylation maintained at 100°C under continuous stirring. Using a 24 full factorial design of experiment, it was found that the degree of substitution (DS) of acetylated sago starch was strongly affected by the ratio of starch to acylating reagents, the ratio of acetic anhydride to acetic acid as the acylating reagents, the concentration of iodine as catalyst and reaction time. The physicochemical characteristics of the acetylated sago starch were assessed based on the FTIR spectra, the XRD spectra, the water absorption index (WAI), and the water solubility index (WSI). SEM was used to study the surface morphology of the acetylated sago starch at different DS.
Stapler and Nonstapler Closure of the Pancreatic Remnant After Distal Pancreatectomy: Multicenter Retrospective Analysis of 388 Patients
Authors: Ban Daisuke , Shimada Kazuaki , Konishi Masaru , Saiura Akio , Hashimoto Masaji , Uesaka Katsuhiko
Published: April 2012

Background

The pancreatic fistula rate following distal pancreatectomy ranges widely, from 13.3 to 64.0 %. The optimal closure method of the pancreatic remnant remains controversial, especially regarding whether to use a stapler.

Methods

All patients who underwent distal pancreatectomy in five Japanese hospitals from January 2001 to June 2009 were included in this study. All relevant, anonymized medical records were entered into an electronic case report form. Complications and pancreatic fistulas were classified according to the Clavien–Dindo classification and the International Study Group of Pancreatic Surgery grading system, respectively.

Results

Of the 388 patients, stapler closure and nonstapler closure were used after distal pancreatectomy in 224 patients (57.7 %) and 164 patients (42.3 %), respectively. Clinically relevant pancreatic fistulas (grades B and C) occurred in 47 patients (21.0 %) treated by stapler closure, which was a significantly lower rate than that for the 83 patients (50.6 %) treated by nonstapler closure. There were no surgical mortalities or in‐hospital deaths. The distribution of postoperative complications was grade 1, 30.7 % (n = 119); grade 2, 40.2 % (n = 156); grade 3a, 0.1 % (n = 5); grade 3b, 0.3 % (n = 1); grade 4a, 0.3 % (n = 1). In the multivariate analysis, diabetes mellitus, previous laparotomy, operating time, and method of stump closure were found to be independently associated with the development of a clinical pancreatic fistula.

Conclusions

Stapler closure is a safe, efficient alternative to standard suture closure techniques because the clinical fistula rate is significantly lower.
Rate of Clinically Significant Postoperative Pancreatic Fistula in Pancreatic Neuroendocrine Tumors
Authors: Inchauste Suzanne M. , Lanier Brock J. , Libutti Steven K. , Phan Giao Q. , Nilubol Naris , Steinberg Seth M. , Kebebew Electron , Hughes Marybeth S.
Published: April 2012

Background

In 2005, the International Study Group of Pancreatic Fistula (ISGPF) developed a definition and grading system for postoperative pancreatic fistula (POPF). The authors sought to determine the rate of POPF after enucleation and/or resection of pancreatic neuroendocrine tumors (PNET) and to identify clinical, surgical, or pathologic factors associated with POPF.

Methods

A retrospective analysis of pancreatic enucleations and resections performed from March 1998 to April 2010. We defined a clinically significant POPF as a grade B that required nonoperative intervention and grade C.

Results

One hundred twenty‐two patients were identified; 62 patients had enucleations and 60 patients had resections of PNET. The rate of clinically significant POPF was 23.7 % (29/122). For pancreatic enucleation, the POPF rate was 27.4 % (17/62, 14 grade B, 3 grade C). The pancreatic resection group had a POPF rate of 20 % (12/60, 10 grade B, 2 grade C). This difference was not significant (p = 0.4). In univariate analyses, patients in the enucleation group with hereditary syndromes (p = 0.02) and non‐insulinoma tumors (p = 0.02) had a higher POPF rate. Patients in the resection group with body mass index (BMI) > 25 (p < 0.01), multiple endocrine neoplasia type 1 (MEN‐1; p < 0.01) and those who underwent simultaneous multiple procedures (p = 0.02) had a higher POPF rate. Multivariate analyses revealed that hereditary syndromes were able to predict POPF in the enucleation group, while having BMI > 25 and increasing lesion size were also associated with POPF in the group undergoing resection.

Conclusions

We found a clinically significant POPF rate after surgery in PNET to be 23.7 % with no difference by the type of operation. Our POPF rate is comparable to that reported in the literature for pancreatic resection for other types of tumors. Certain inherited genetic diseases—von Hippel–Lindau disease (VHL) and MEN‐1—were associated with higher POPF rates.
Patients with Multiple Hepatocellular Carcinomas Within the UCSF Criteria Have Outcomes After Curative Resection Similar to Patients Within the BCLC Early‐Stage Criteria
Authors: Zhao Wen‐Chao , Yang Ning , Zhu Nan , Zhang Hai‐Bin , Fu Yong , Zhou Hua‐Bang , Cai Wen‐Ke , Chen Ben‐Dong , Yang Guang‐Shun
Published: April 2012

Background

Surgical strategies for the treatment of multiple hepatocellular carcinomas (HCC) remain controversial. This study compared the prognostic power of the University of California, San Francisco (UCSF) criteria with the Barcelona Clinic Liver Cancer (BCLC) early‐stage criteria.

Methods

Clinical and survival data of 162 multiple‐HCC patients in Child‐Pugh class A who underwent curative resection were retrospectively reviewed. Prognostic risk factors were analyzed using univariate and multivariate analyses.

Results

UCSF criteria were shown to independently predict overall and disease‐free survival. In patients within the UCSF criteria, 3‐year overall and disease‐free survivals were significantly better than in those exceeding the UCSF criteria (68 vs. 34 % and 54 vs. 26 %, respectively; both p < 0.001). There were no significant differences in 3‐year overall and disease‐free survival between patients within the UCSF criteria but exceeding the BCLC early stage and patients with BCLC early‐stage disease (71 vs. 66 %, p = 0.506 and 57 vs. 50 %, p = 0.666, respectively). Tumors within the UCSF criteria were associated with a lower incidence of high‐grade tumor (p = 0.009), microvascular invasion (p = 0.005), 3‐month death (p = 0.046), prolonged Pringle’s maneuver (p = 0.005), and surgical margin <0.5 cm (p < 0.001) than those exceeding the UCSF criteria. Tumors within the UCSF criteria but exceeding the BCLC early stage had invasiveness and surgical difficulty similar to those within the BCLC early‐stage criteria.

Conclusions

Multiple HCC patients within the UCSF criteria benefit from curative resection. Expansion of curative treatment is justified.
MicroRNAs: Relevant Tools for a Colorectal Surgeon?
Authors: Peacock Oliver , Lee Andrew C. , Larvin Michael , Tufarelli Cristina , Lund Jonathan N.
Published: April 2012

Colorectal cancer is the third most common malignancy and cause of cancer‐related deaths worldwide. Approximately half of the patients diagnosed with colorectal cancer ultimately die of the condition. Death from colorectal cancer can be prevented by early detection, but unfortunately presentation is often late, with a worse prognosis. Screening by fecal occult blood testing reduces disease‐specific mortality, but there is a need for sensitive and specific noninvasive biomarkers to facilitate detecting the disease, staging it, and predicting the best therapeutic options. MicroRNAs (miRNAs) are short noncoding RNA sequences that have a crucial role in the regulation of gene expression. They have significant regulatory functions in basic cellular processes, such as cell differentiation, proliferation, and apoptosis. Evidence suggests that miRNAs may function as both tumor suppressors and oncogenes. The main mechanism for changes in the function of miRNAs in cancer cells is due to aberrant gene expression. Accurate discrimination of miRNA profiles between tumor and normal mucosa in colorectal cancer allows definition of specific expression patterns of miRNAs, giving good potential as diagnostic and therapeutic targets. MiRNAs expressed in colorectal cancers are also abundantly present and stable in stool and plasma samples. Their extraction from these three sources is feasible and reproducible. The ease and reliability of determining miRNA profiles in plasma or stool makes them potential molecular markers for colorectal cancer screening. This review summarizes the role miRNAs have in colorectal cancer, highlighting particularly the potential diagnostic, prognostic, and therapeutic implications in the future treatment of the disease.
Clinical Significance of Gastric Cancer Surveillance in Renal Transplant Recipients
Authors: Lee In‐Seob , Kim Tae‐Hwan , Kim Young‐Hoon , Yook Jeong‐Hwan , Kim Byung‐Sik , Han Duck‐Jong
Published: April 2012

Background

Posttransplant malignancy is one of the major causes inhibiting long‐term graft survival. Gastric adenocarcinoma is the most common malignancy in Korea and occurs more frequently in renal transplant recipients compared to that in Western countries. We aimed to analyze the clinical features of the post‐renal‐transplant gastric cancer and assess factors that can affect the difference in survival.

Methods

Of the 2,157 recipients who underwent renal transplantation at Asan Medical Center between January 1992 and April 2008, the 13 patients diagnosed with gastric adenocarcinoma after transplantation were retrospectively reviewed. We analyzed the effects of primary disease causing end‐stage renal disease, type of donor, type of immunosuppressant, induction therapy, and organ rejection on survival after cancer diagnosis. In addition, we evaluated the need for regular gastric cancer screening after transplantation by analyzing the difference in survival between the patients who were and were not screened on a regular basis.

Results

Gastric adenocarcinoma occurred 3.44 times more often in men and 8.33 times more often in women than in the same age group of the general population in Korea (176.4/100,000 in men and 67.6/100,000 in women). Except for endoscopic screening, survival had no relation to the primary disease, type of donor, type of immunosuppressive drug, induction therapy, or the presence of rejection. The 5‐year survival rates of recipients who were and were not screened by regular gastroscopic surveillance were 100 and 53.6 %, respectively (p = 0.06).

Conclusions

Regular gastric surveillance might be needed for renal transplant recipients with a high risk of gastric malignancy.
Predictors of Missed Appointments in Prospective Hand Surgery Research
Authors: Ootes Daan , Buijze Geert A. , Ring David
Published: April 2012

Background

Missed research appointments may bias the outcome of prospective clinical trials if the participants that miss appointments differ in important ways from those that do not. The purpose of this study was to determine the predictors of missed research appointments in patients enrolled in clinical trials.

Methods

We retrospectively evaluated 665 participants enrolled in ten prospective clinical trials conducted at our outpatient office between 2001 and 2010. Demographic data (sex, race, date of birth, date of enrollment, age at enrollment, educational level, and work status), study coordinator, and study type were analyzed for association with missed a research appointment in bivariate and multiple logistic regression analyses.

Results

One hundred and forty-four (21.7 %) participants missed research appointments during their follow-up. There were no statistical differences between those who missed appointments and those who did not, regarding sex, race, and age at enrollment. Educational level and work status were independent predictors of missed appointments.

Conclusions

This study suggests that educational level and work status are predictors of missed appointments in prospective clinical research.
The Effect of Temperature and Moisture Content of Stored Rapeseed on the Phytosterol Degradation Rate
Authors: Gawrysiak‐Witulska Marzena , Rudzińska Magdalena , Wawrzyniak Jolanta , Siger Aleksander
Published: April 2012

The effect of temperature (25 or 35 °C) and moisture content (10, 12.5, 15.5 %) on rapeseed phytosterol degradation was examined for 18 days. Statistical analysis showed that temperature, moisture and time of storage have a significant effect on phytosterol degradation. After 18 days of seed storage at a temperature of 25 and 30 °C losses of these compounds amounted to 11 and 13 % in seeds with moisture contents of 10, 12 and 16 % in seeds with a moisture content of 12.5 %, while they were 24 and 58 % in seeds with a moisture content of 15.5 %. Among all the identified sterols the greatest degradation rate was observed for stigmasterol and brassicasterol. Losses of stigmasterol and brassicasterol during storage of seeds with a 12.5 % moisture content at a temperature of 30 °C were 17 and 28 %, respectively, while in seeds with a moisture content of 15.5 % these losses increased to 73 and 63 %.