bluuebunny/crossref_metadata_2025 huggingface dataset:
Purification, immobilization, and characterization of protease from local Bacillus subtilis M‐11
Authors: Sahin Selmihan , Ozmen Ismail , Kir Esengul
Published: February 2015

Protease from Bacillus subtilis M‐11 was produced and purified using ammonium sulfate precipitation, gel filtration chromatography with 15.8‐fold. The purified enzyme showed a single band on sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, and it was determined that its molecular weight was 32 kDa. The purified enzyme was immobilized on polysulfone membrane containing Silica gel‐3 aminopropyltriethoxysilane (Si‐APTS) by physical adsorption. The optimal immobilization conditions (pH, temperatures, and incubation time) were investigated. The properties of immobilized protease were determined and compared with free enzyme. The investigations on immobilized enzyme indicated that the optimum pH was shifted 0.5 units to alkaline pH (pH 8.0–8.5) after immobilization with physical adsorption. Immobilization improved pH stability of enzyme between pH 7.5 and 8.5. Immobilized enzyme sustained 77.3% of its activity after usage of 10 times. However, there is no change on optimum temperature (50 °C) after immobilization.

All these results indicated that polysulfone membrane containing Si‐APTS could be a proper support for protease immobilization, and immobilized protease by using physical adsorption could be used for industrial applications efficiently. © 2015 Curtin University of Technology and John Wiley & Sons, Ltd.
Preparation and characterization of LDPE/PVA blend films filled with glycerin‐plasticized polyvinyl alcohol
Authors: Kim Dowan , Jung Jeyoung , Park Su‐il , Seo Jongchul
Published: February 2015

A series of LDPE/PVA blend films were prepared via a twin‐screw extruder, and their morphology, thermal property, oxygen and water vapor permeation, surface properties, and mechanical properties were investigated as a function of the PVA content. During the extrusion process of the blend films, glycerin improved the compatibility and processing conditions between LDPE and PVA. The melting temperature (Tm), melting enthalpy (ΔHm), crystallinity (%), and thermal stability of the thermal decomposition temperature (T5%) of the LDPE/PVA blend films decreased with increasing PVA content. The oxygen permeabilities of the blend films decreased from 24.0 to 11.4 cm3·cm (m2·day·atm)−1 at 23°C. The WVTR increased from 7.8 to 15.0 g(m2 day)−1 and the water uptake increased from 0.13 to 9.31%, respectively. The mechanical properties of blend films were slightly enhanced up to 2% PVA and then decreased. The physical properties of the blend films strongly varied with the chemical structure and morphology depending on the PVA and glycerin. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41985.
Synthesis of Desaza Analogues of Annomontine and Canthin‐4‐one Alkaloids
Authors: Strödke Benjamin , Gehring André P. , Bracher Franz
Published: February 2015

1‐Acetylcarbazoles are readily converted to 3‐desazacanthin‐4‐ones upon treatment with Bredereck's reagent, but in contrast to canthin‐4‐ones, these do not undergo ring transformation reactions with guanidine. Only after N‐protection (methyl or 2‐(trimethylsilyl)ethoxymethyl group), 2‐desaza analogues of the alkaloid annomontine are accessible via the enaminoketones obtained by condensation with Bredereck's reagent. One of the annomontine analogues is an inhibitor of the Plasmodium falciparum CDC‐like kinases (CLK) and shows antimalarial activity.
Design, Synthesis and In Vitro Antiproliferative Activity of Novel Isatin‐Quinazoline Hybrids
Authors: Fares Mohamed , Eldehna Wagdy M. , Abou‐Seri Sahar M. , Abdel‐Aziz Hatem A. , Aly Mohamed H. , Tolba Mai F.
Published: February 2015

Using a molecular hybridization approach, a new series of isatin‐quinazoline hybrids 15a–o was designed and synthesized via two different synthetic routes. The target compounds 15a–o were prepared by the reaction of quinazoline hydrazines 12a–e with indoline‐2,3‐diones 13a–c or by treating 4‐chloroquinazoline derivatives 11a–e with isatin hydrazones 14a–c. The in vitro anticancer activity of the newly synthesized hybrids was evaluated against the liver HepG2, breast MCF‐7 and colon HT‐29 cancer cell lines. A distinctive selective growth inhibitory effect was observed towards the HepG2 cancer cell line. Compounds 15b, 15g and 15l displayed the highest potency, with IC50 values ranging from 1.0 ± 0.2 to 2.4 ± 0.4 μM, and they were able to induce apoptosis in HepG2 cells, as evidenced by enhanced expression of the pro‐apoptotic protein Bax and reduced expression of the anti‐apoptotic protein Bcl‐2, in addition to increased caspase‐3 levels.
Synthesis of Novel Tetrahydrobenzazepine Derivatives and Their Cytoprotective Effect on Human Lymphocytes
Authors: Simic Milena R. , Stankovic Miroslava , Mandic Boris M. , Tesevic Vele V. , Savic Vladimir M.
Published: February 2015

Cytoprotective compounds such as amifostine play an important role in chemo‐ and radiotherapy due to their ability to reduce the side effects of these treatments. Our work was initiated with the intention to design, synthesise and test a new class of heterocyclic compounds that would have an antioxidative profile with the potential to be further developed as cytoprotective agents. The design was based on the privileged tetrahydrobenzazepine scaffold found in many natural products with a wide range of biological properties. This structure was further functionalised with moieties known to possess antioxidative features such as tertiary amine and styrene double bond. A series of eight tetrahydrobenzazepine derivatives of isoquinoline, 3,4‐dihydro‐β‐carboline and pyridine were synthesised employing the Heck reaction as a key transformation. Some of the prepared compounds were tested for their in vitro effects on chromosome aberrations in peripheral human lymphocytes using the cytochalasin‐B blocked micronucleus (MN) assay. Three tetrahydrobenzoazepine derivatives showed significant cytoprotective properties, comparable or even better to those of the radioprotective agent amifostine.
Mechanisms of bacterial morphogenesis: Evolutionary cell biology approaches provide new insights
Authors: Jiang Chao , Caccamo Paul D. , Brun Yves V.
Published: February 2015

How Darwin's “endless forms most beautiful” have evolved remains one of the most exciting questions in biology. The significant variety of bacterial shapes is most likely due to the specific advantages they confer with respect to the diverse environments they occupy. While our understanding of the mechanisms generating relatively simple shapes has improved tremendously in the last few years, the molecular mechanisms underlying the generation of complex shapes and the evolution of shape diversity are largely unknown. The emerging field of bacterial evolutionary cell biology provides a novel strategy to answer this question in a comparative phylogenetic framework. This relatively novel approach provides hypotheses and insights into cell biological mechanisms, such as morphogenesis, and their evolution that would have been difficult to obtain by studying only model organisms. We discuss the necessary steps, challenges, and impact of integrating “evolutionary thinking” into bacterial cell biology in the genomic era.
Characterization and luminescence properties of CaMgSi2O6:Eu2+ blue phosphor
Authors: Chandrakar P. , Baghel R. N. , Bisen D. P. , Chandra B. P.
Published: February 2015

A blue CaMgSi2O6:Eu2+ phosphor was prepared by the solid‐state reaction method and the phosphor characterized in terms of crystal structure, particle size, photoluminescence (PL), thermoluminescence (TL) and mechanoluminescence (ML) properties using X‐ray diffraction (XRD), transmission electron microscopy (TEM), PL spectroscopy, TLD reader and ML impact technique. The XRD result shows that phosphor is formed in a single phase and has a monoclinic structure with the space group C2/c. Furthermore, the PL excitation spectra of Eu2+‐doped CaMgSi2O6 phosphor showed a strong band peak at 356 nm and the PL emission spectrum has a peak at 450 nm. The depths and frequency factors of trap centers were calculated using the TL glow curve by deconvolution method in which the trap depths were found to be 0.48 and 0.61 eV. The formation of CaMgSi2O6:Eu2+ phosphor was confirmed by Fourier transform infrared spectroscopy. The ML intensity increased linearly with the impact velocity of the piston used to deform the phosphor. It was shown that the local piezoelectricity‐induced electron bombardment model is responsible for the ML emission. Finally, the optical properties of CaMgSi2O6:Eu2+ phosphors are discussed. Copyright © 2015 John Wiley & Sons, Ltd.
Intrinsic Enantioselectivity of Natural Polynucleotides Modulated by Copper Ions
Authors: Fu Yan , Chen Xiongfei , Zhang Jinli , Li Wei
Published: February 2015

Natural polynucleotides including Micrococcus lysodeikticus and calf thymus DNA exhibit enantioselective recognition to S‐ofloxacin regulated by Cu2+. This is the first report that ofloxacin and Cu2+ have cooperative effects on the local distortions of polynucleotides. At the [Cu2+]/[base] ratio of 0.1, S‐ofloxacin is more liable to induce the locally distorted structures of polynucleotides, of which the association constant of S‐ofloxacin toward DNA‐Cu(II) is three times higher than that of the R‐enantiomer. The apparent increase of adsorption capability and cooperativity, as well as the change of adsorption mechanism were detected in the adsorption of ofloxacin enantiomers on polynucleotides upon Cu(II)‐coordination. This study not only discloses the effect of the chiral drug on the structural transition of long double‐stranded DNA, but provides fundamental data to develop a novel enantioseparation method based on natural polynucleotides. Chirality 27:306‐313, 2015. © 2015 Wiley Periodicals, Inc.
On Fractional GJMS Operators
Authors: Case Jeffrey S. , Alice Chang Sun‐Yung
Published: February 2015

We describe a new interpretation of the fractional GJMS operators as generalized Dirichlet‐to‐Neumann operators associated to weighted GJMS operators on naturally associated smooth metric measure spaces. This gives a geometric interpretation of the Caffarelli‐Silvestre extension for (−Δ)γ when γ ∊ (0,1), and both a geometric interpretation and a curved analogue of the higher‐order extension found by R. Yang for (−Δ)γ when γ > 1. We give three applications of this correspondence. First, we exhibit some energy identities for the fractional GJMS operators in terms of energies in the compactified Poincaré‐Einstein manifold, including an interpretation as a renormalized energy. Second, for γ ∊ (1,2), we show that if the scalar curvature and the fractional Q‐curvature Q2γ of the boundary are nonnegative, then the fractional GJMS operator P2γ is nonnegative. Third, by assuming additionally that Q2γ is not identically zero, we show that P2γ satisfies a strong maximum principle.© 2016 Wiley Periodicals, Inc.
Stereoselective Synthesis of Highly Functionalized Dispirooxindoles through [3+2] Cycloaddition of Carbonyl Ylides with 3‐Arylideneoxindoles
Authors: Reddy Basi V. Subba , Karthik Govindaraju , Rajasekaran Tamilselvan , Sridhar Balasubramanian
Published: February 2015

The three‐component coupling (3CC) of α‐diazoamide, aldehyde and 3‐arylideneoxindole using 5 mol‐% of Rh2(OAc)4 is described to afford a novel class of dispirooxindole derivatives with complete regio‐ and stereoselectivity. It is a first report on the synthesis of natural product inspired libraries of dispirooxindoles through a carbonyl ylide cycloaddition.
Reservoir modeling for Wabamun lake sequestration project
Authors: Ghaderi Seyyed M. , Leonenko Yuri
Published: February 2015

A study, entitled “Wabamun Lake Sequestration Project” or “WASP,” was performed to evaluate large‐scale CO2 storage opportunities in the Wabamun area including potential risks. The project examined the feasibility of storing 20 megatons (Mt) of CO2 per year over 50 years. This scale is one order of magnitude larger than the typical benchmark (1 Mt/year) used in academic research and commercial projects that are currently in place or under review. The study was conducted by a group of researchers from several universities as well as industry consultants. This study presents an overview of the reservoir modeling part of this study, which the authors were responsible for. The main objectives of the reservoir modeling for WASP project were as follows: (1) estimation of storage capacity (traditionally, this value is projected based on the available pore space, but we have an additional practical consideration: the maximum amount one can inject within short period of time [~50 years] and within a localized injection area [~30 km × 90 km]); (2) investigation of CO2 plume movement and pressure distribution during and after injection including the effect of formation dip angle on the plume shape and its migration; (3) investigation of the long‐term fate of injection associated with free phase CO2 (risks of leakage) and aquifer pressurization (possible geomechanical changes and related phenomena); (4) investigation of the phase behavior of H2S initially available and dissolved in brine during CO2 sequestration process. The WASP reservoir modeling study mentioned above led to a few important findings. The most important one is that, when CO2 is being injected into a sour aquifer, initially dissolved H2S will release into the expanding CO2 plume and accumulate at the leading edge of the plume. Also, the large‐scale injection scheme (20 Mt/year), which requires multi well injectors, provides very different pressure response compared to a one well (1 Mt/year) scenario.
OpenACC acceleration of an unstructured CFD solver based on a reconstructed discontinuous Galerkin method for compressible flows
Authors: Xia Yidong , Lou Jialin , Luo Hong , Edwards Jack , Mueller Frank
Published: February 2015

An OpenACC directive‐based graphics processing unit (GPU) parallel scheme is presented for solving the compressible Navier–Stokes equations on 3D hybrid unstructured grids with a third‐order reconstructed discontinuous Galerkin method. The developed scheme requires the minimum code intrusion and algorithm alteration for upgrading a legacy solver with the GPU computing capability at very little extra effort in programming, which leads to a unified and portable code development strategy. A face coloring algorithm is adopted to eliminate the memory contention because of the threading of internal and boundary face integrals. A number of flow problems are presented to verify the implementation of the developed scheme. Timing measurements were obtained by running the resulting GPU code on one Nvidia Tesla K20c GPU card (Nvidia Corporation, Santa Clara, CA, USA) and compared with those obtained by running the equivalent Message Passing Interface (MPI) parallel CPU code on a compute node (consisting of two AMD Opteron 6128 eight‐core CPUs (Advanced Micro Devices, Inc., Sunnyvale, CA, USA)). Speedup factors of up to 24× and 1.6× for the GPU code were achieved with respect to one and 16 CPU cores, respectively. The numerical results indicate that this OpenACC‐based parallel scheme is an effective and extensible approach to port unstructured high‐order CFD solvers to GPU computing. Copyright © 2015 John Wiley & Sons, Ltd.
Contrast enhancement using real coded genetic algorithm based modified histogram equalization for gray scale images
Authors: Babu P. , Rajamani V.
Published: February 2015

Histogram equalization is a well‐known technique used for contrast enhancement. The global HE usually results in excessive contrast enhancement because of lack of control on the level of contrast enhancement. A new technique named modified histogram equalization using real coded genetic algorithm (MHERCGA) is aimed to sweep over this drawback. The primary aim of this paper is to obtain an enhanced method which keeps the original brightness. This method incorporates a provision to have a control over the level of contrast enhancement and applicable for all types of image including low contrast MRI brain images. The basic idea of this technique is to partition the input image histogram into two subhistograms based on a threshold which is obtained using Otsu's optimality principle. Then, bicriteria optimization problem is formulated to satisfy the aforementioned requirements. The subhistograms are modified by selecting optimal contrast enhancement parameters. Finally, the union of the modified subhistograms produce a contrast enhanced and details preserved output image. While developing an optimization problem, real coded genetic algorithm is applied to determine the optimal value of contrast enhancement parameters. This mechanism enhances the contrast of the input image better than the existing contemporary HE methods. The quality of the enhanced brain image indicates that the image obtained after this method can be useful for efficient detection of brain cancer in further process like segmentation, classification, etc. The performance of the proposed method is well supported by the contrast enhancement quantitative metrics such as discrete entropy and natural image quality evaluator. © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 24–32, 2015
The nonlinear variation regularization algorithm for the magnetic resonance electrical impedance tomography
Authors: Liu Jin‐Zhen , Xiong Hui , Li Gang , Lin Ling
Published: February 2015

The nonlinear variation regularization algorithm (NVRA) is an effective method to enhance the contrast and robustness of the reconstruction in medical imaging. In order to improve the reconstruction quality the variation regularization is introduced to the nonlinear algorithm based on one component of the magnetic flux density by injecting one current. Firstly, we propose a novel algorithm for magnetic resonance electrical impedance tomography (MREIT) using NVRA, and clarify the implementation of this algorithm. Secondly, we analyze the performance of the proposed nonlinear algorithm and the linear sensitivity method with noisy data in the phantom models. Finally, in the case of 0.36 T low field intensity magnetic resonance scanner, we present the method for reducing the electrode model error, and evaluate the performance of two reconstruction algorithms in the agar gel model. The results indicate that the NVRA is able to improve the reconstruction quality with sharp contrast and more robust to noise in comparison to the sensitivity method. In addition, this study shows that with just one current injection and one component of the magnetic flux density we can obtain a high quality imaging, which promotes the MREIT in clinical application. © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 68–76, 2015
A rapid automatic brain tumor detection method for MRI images using modified minimum error thresholding technique
Authors: T Kalaiselvi , P Nagaraja
Published: February 2015

This proposed work is aimed to develop a rapid automatic method to detect the brain tumor from T2‐weighted MRI brain images using the principle of modified minimum error thresholding (MET) method. Initially, modified MET method is applied to produce well segmented and sub‐structural clarity for MRI brain images. Further, using FCM clustering the appearance of tumor area is refined. The obtained results are compared with corresponding ground truth images. The quantitative measures of results were compared with the results of those conventional methods using the metrics predictive accuracy (PA), dice coefficient (DC), and processing time. The PA and DC values of the proposed method attained maximum value and processing time is minimum while compared to conventional FCM and k‐means clustering techniques. This proposed method is more efficient and faster than the existing segmentation methods in detecting the tumor region from T2‐weighted MRI brain images. © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 77–85, 2015
Universal Enterprise Adaptive Object Model: A Semantic Web‐Based Implementation of Organizational Self‐Awareness
Authors: Aveiro David , Pinto Duarte
Published: February 2015

In this paper we present a novel conceptual model that systematizes the integrated management and adaptation of: (1) enterprise models, (2) their representations, (3) their underlying meta‐models (i.e. their abstract syntax) and (4) the representation rules (i.e. concrete syntax for the respective models). All this for different modelling languages and also different versions of these languages. Thanks to our original use of the adaptive object model and type square patterns—normally applied in the context of software engineering, but here applied for enterprise engineering—we manage to provide a strong conceptual foundation for the development of software tools that allow a precise and coherent specification of models and their evolution and also of meta‐models and their evolution. We also present a prototype of such a tool currently being developed to enable collaborative enterprise ontology model management using the Semantic MediaWiki as a base framework. This solution is solidly grounded on the theoretical foundations of organizational self‐awareness and Ψ‐theory of enterprise ontology and is a valuable contribution to facilitate general and distributed enterprise model management and also concrete and abstract syntax specification (i.e. the specification of a language's meta‐model). This allows flexibility and ease of use in creation and adaptation of organizational models and also the use of semantic queries to detect and inform users on any violation of meta‐model rules. Copyright © 2015 John Wiley & Sons, Ltd.
e‐Textbooks
Authors: Dobler Elizabeth
Published: February 2015

This article explores the digital reading preferences and strategies used by preservice teachers when reading an e‐textbook in a literacy methods course. The use of e‐textbooks is becoming more prevalent due to an increase in access to mobile devices, acceptance of e‐books in general, and the high cost of print textbooks. To ensure comprehension, teachers need an awareness of e‐textbook features and the processes for effectively reading text with embedded web links, video clips, and audio files. In this study, some participants described an increase in cognitive engagement due to the ability to both utilize e‐textbook features and engage with media, in addition to text. Others found the process of reading an e‐textbook challenging because of distractions on their device, eye strain, and a feeling of being overwhelmed with choices. Overall the preservice teachers expressed a preference for choice between using print, electronic format, or both.
Intravenous methylprednisolone versus therapeutic plasma exchange for treatment of anti‐n‐methyl‐d‐aspartate receptor antibody encephalitis: A retrospective review
Authors: DeSena Allen D. , Noland Daniel K. , Matevosyan Karen , King Kathryn , Phillips Lauren , Qureshi Sara S. , Greenberg Benjamin M. , Graves Donna
Published: February 2015

Introduction: Anti‐N‐methyl‐d‐aspartate (NMDA) receptor antibody encephalitis is an increasingly recognized form of autoimmune encephalitis. Conventional treatments include therapies such as corticosteroids, intravenous immunoglobulin (IVIg), and/or therapeutic plasma exchange (TPE). Although TPE is regularly used for treatment of anti‐NMDA receptor antibody encephalitis, the American Society for Apheresis has given it a category III recommendation only. Earlier administered immunotherapies in tumor‐negative patients may facilitate faster recoveries, but it remains unclear whether or not TPE is superior to steroids and/or IVIG. Methods: We retrospectively evaluated 10 of 14 patients that received steroids and TPE with modified Rankin scores and subjectively assessed the point of largest sustained improvement in all 14 patients. Results: In the patients that received both steroids and TPE at our institution during the same hospitalization (only 10 of 14 patients), 7/10 patients after TPE had improved with the modified Rankin score versus 3/10 patients after steroids. The average modified Rankin score improvement after steroids in this group was −0.1 as compared with 0.4 after TPE. Based on subjective chart review analysis during which all 14 patients were assessed, the largest sustained improvement occurred immediately following the third–fifth exchange in 9/14 patients, whereas only 2/14 patients appeared to have had significant benefit immediately following steroids. Conclusions: This is compelling preliminary data that suggests that corticosteroids may not be as effective compared to steroids followed by TPE. Given the importance of time‐sensitive treatment, more formal studies may illuminate the ideal first‐line treatment for anti‐NMDA receptor antibody encephalitis. J. Clin. Apheresis 30:212–216, 2015. © 2015 Wiley Periodicals, Inc.
Comparison of MALDI‐TOF mass spectra with microsatellite length polymorphisms in Candida albicans
Authors: Dhieb C. , Normand A. C. , L'Ollivier C. , Gautier M. , Vranckx K. , El Euch D. , Chaker E. , Hendrickx M. , Dalle F. , Sadfi N. , Piarroux R. , Ranque S.
Published: February 2015

Candida albicans is the most frequent yeast involved in human infections. Its population structure can be divided into several genetic clades, some of which have been associated with antifungal susceptibility. Therefore, detecting and monitoring fungal clones in a routine laboratory setting would be a major epidemiological advance. Matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectra results are now widely used as bar codes to identify microorganisms in clinical microbiology laboratories. This study aimed at testing MALDI‐TOF mass spectra bar codes to identify clades among a set of C. albicans isolates.

Accordingly, 102 clinical strains were genotyped using 10 microsatellite markers and analyzed via MALDI‐TOF mass spectrometry. The mass spectra were compared with a reference spectral library including 33 well‐characterized collection strains, using a MicroflexTM system and BiotyperTM software, to test the capacity of the spectrum of a given isolate to match with the reference mass spectrum of an isolate from the same genetic clade.

Despite high confidence species identification, the spectra failed to significantly match with the corresponding clade (p = 0.74). This was confirmed with the MALDI‐TOF spectra similarity dendrogram, in which the strains were dispersed irrespective of their genetic clade. Various attempts to improve intra‐clade spectra recognition were unsuccessful.

In conclusion, MALDI‐TOF mass spectra bar code analysis failed to reliably recognize genetically related C. albicans isolates. Further studies are warranted to develop alternative MALDI‐TOF mass spectra analytical approaches to identify and monitor C. albicans clades in the routine clinical laboratory. Copyright © 2015 John Wiley & Sons, Ltd.
Eye‐safe UV stand‐off Raman spectroscopy for the ranged detection of explosives in the field
Authors: Carroll Joshua A. , Izake Emad L. , Cletus Biju , Jaatinen Esa
Published: February 2015

Increasing worldwide terrorist attacks involving explosives presents a growing need for a rapid and ranged explosive detection method that can safely be deployed in the field. Stand‐off Raman spectroscopy shows great promise; however, the radiant exposures of lasers required for adequate signal generation are often much greater than what is safe for the eye or the skin, restricting use of the technique to unpopulated areas. Here, by determining the safe exposure levels for lasers typically used in Raman spectroscopy, optimal parameter values are identified, which produce the largest possible detection range using power densities that do not exceed the eye‐safe limit. It is shown that safe ultraviolet pulse energies can be more than three orders of magnitude greater than equivalent safe visible pulse energies. Coupling this to the 16‐fold increase in Raman signal obtained in the ultraviolet at 266 nm over that at 532 nm results in a 131 times larger detection range for the eye‐safe 266‐nm system over an equivalent eye‐safe 532‐nm laser system. For the Raman system described here, this translates to a maximum range of 42 m for detecting Teflon with a 266‐nm laser emitting a 100‐mm diameter beam of 23.5‐mJ nanosecond pulses. Copyright © 2015 John Wiley & Sons, Ltd.
Characterisation of general proteolytic, milk clotting and antifungal activity of Ficus carica latex during fruit ripening
Authors: Raskovic Brankica , Lazic Jelena , Polovic Natalija
Published: February 2015

BACKGROUND

The physiological role of fig latex is to protect the plant from pathogens. Latex is a rich source of proteases, predominantly ficin. Fig latex also contains collagenolytic protease and chitinolytic enzymes. Our aim was to investigate changes in protein composition, enzyme and antifungal activities of fig latex during fruit ripening.

RESULTS

Comparison of latex samples in different time periods showed a uniform increase of protein concentration in chronological order. The content of collagenolytic protease did not differ significantly in the latex samples, while the content of ficin decreased. Ficin‐specific activity towards casein was the highest at the beginning of fruit development (about 80 U mg−1). Specific milk clotting activity increased as well as the abundance of casein band in the clots. Specific chitinolytic activity at the beginning of flowering was 6.5 times higher than the activity in the period when fruits are ripe. Antifungal activity is the most extensive in spring.

CONCLUSION

Ficin forms with different casein specificities are present in different proportions during fruit ripening, which is of importance for applications in the dairy industry. The protection mechanism against insects and fungi, which relies on chitinolytic activity, is the most important in the early phases of flowering and is replaced with other strategies over time. © 2015 Society of Chemical Industry
Quadratic and linear controls developing an optimal treatment for the use of BCG immunotherapy in superficial bladder cancer
Authors: Elmouki Ilias , Saadi Smahane
Published: February 2015

Our prime objective of the study is to exhibit the advantage to introduce a quadratic control in place of linear control in a cost function to be minimized, and that is associated to an optimal control problem that we formulate for a pre‐validated model of bacillus Calmette‐Guérin (BCG) immunotherapy in superficial bladder cancer. The compartmental model of interest is in the form of a nonlinear system of four ordinary differential equations that describe interactions between the used BCG strain, tumor cells, and immune responses. Previous studies reported that the optimal dose of BCG for treating bladder cancer is yet unknown. Hence, we aim to establish the optimization approach that can be applied for determining the values of the optimal BCG concentration along the therapy period to stimulate immune‐system cells and reduce cancer cells growth during BCG intravesical therapy. Pontryagin's maximum principle and the generalized Legendre–Clebsch condition are employed to provide the explicit formulations of the sought optimal controls. The optimality system is resolved numerically based on a fourth‐order iterative Runge–Kutta progressive‐regressive scheme, which is used to solve a two‐point boundary value problem. Copyright © 2015 John Wiley & Sons, Ltd.
Modulating Low Energy Ion Plasma Fluxes for the Growth of Nanoporous Thin Films
Authors: Alvarez Rafael , Lopez‐Santos Carmen , Ferrer Francisco J. , Rico Victor , Cotrino José , Gonzalez‐Elipe Agustín R. , Palmero Alberto
Published: February 2015

The growth of nanoporous layers by plasma‐assisted deposition techniques is strongly mediated by the ion fluxes in the reactor. To analyze their influence we have deposited different nanostructured thin films by the magnetron sputtering technique at oblique angles, modulating the ion fluxes in the plasma by tuning the frequency of the electromagnetic signal from pure DC to 160 kHz DC pulsed mode. In the DC case, ions possess energies below 5 eV and do not induce noticeable changes in the film structure. However, when the signal is pulsed, ions with energies up to 40 eV impinge on the film, decreasing the porosity of the layers and tilting down the porous/nanocolumnar structures. As a result, we demonstrate that the overall porosity of the layers and the tilt angle of the columns can be tailored as two independent morphological quantities.
Micro‐Raman spectroscopy as a complementary technique to high resolution X‐ray diffraction for the characterization of Si1‐xGex thin layers
Authors: Durand Aurèle , Rouchon Denis , Le‐Cunff Delphine , Gergaud Patrice
Published: February 2015

In advanced transistor technology, Silicon‐Germanium alloy (SiGe) is being used as a replacement for Si channels to achieve higher mobility. Among the various characterization techniques μ‐Raman spectroscopy is a promising candidate due to a good spatial resolution and low detection threshold. This study presents the evaluation of the technique for the measurement of Ge concentration and comparison to other metrology techniques. As a first step to evaluate the μ‐Raman capability, we considered a simple case of thin SiGe films from 12nm down to 4 nm thickness. Assuming an epitaxial pseudomorphic structure, the Ge content has been extracted for all samples with an average 0.3% stability and at least 1% accuracy as confirmed by high resolution X‐ray diffraction (HRXRD) and secondary ion mass spectrometry analysis (SIMS). We then studied a more complex structure of SiGe on fully depleted‐silicon on insulator (FD‐SOI) as being critical for the development of condensation process of advanced transistor technology. Since μ‐Raman requires prior knowledge of the structural state of the layer, we discuss the interest to combine μ‐Raman measurements with X‐rays diffraction in order to extract the Ge composition on such stacks. μ‐Raman shows a real potential for thin SiGe film characterization and it does not suffers of the lack of precision for very thin films as HRXRD does, however there are still some developments to be made before using it as a metrology technique. Moreover, it could be interesting to couple the technique with HRXRD measurement. The approach to control SiGe condensation process on FD‐SOI might suggest interesting experiment. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control current stress technique for the investigation of gate dielectrics of MIS devices
Authors: Andreev Vladimir V. , Bondarenko Gennady G. , Maslovsky Vladimir M. , Stolyarov Alexander A. , Andreev Dmitry V.
Published: February 2015

In this study, a modified technique of control current stress to investigation thin gate dielectric of MIS structures is proposed. This technique allows to monitor charge trapping in gate dielectric of MIS structures under high‐field and another stress situations (irradiation, plasma, hot carriers, etc.). The technique also may be used for testing thin gate dielectric defects. Unlike simple techniques, for example constant current stress and J‐ramp current stress, the proposed method uses a sequence of stress current and measuring current pulses. At the same time, the processes of charging and discharging of the MIS structure capacitance as well as the charge trapping in the gate dielectric are taken into account. Charging of MIS structure from inversion to accumulation modes or back way allows one to retrieve a low frequency capacitive‐voltage characteristic. Account charging capacitance of MIS structure and charge trapping in gate dielectric at injective mode lets considerably increase metrological characteristics of this technique and reduce inaccuracies. The models describing the change in the charge state of MIS structures, both in the charge capacity, and in the mode of injection of charge carriers were developed. Using these models let to choose optimal algorithm of current stress and increase measurement accuracy. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermally evaporated Ag nanoparticle films for plasmonic enhancement in organic solar cells: effects of particle geometry
Authors: Haidari Gholamhosain , Hajimahmoodzadeh Morteza , Fallah Hamid Reza , Peukert Andreas , Chanaewa Alina , von Hauff Elizabeth
Published: February 2015

We report on the simple fabrication of Ag NP films via thermal evaporation and subsequent annealing. The NPs are formed on indium tin oxide electrodes, coated with PEDOT:PSS and implemented into PCPDTBT:PC70BM solar cells. Scanning electron microscopy and atomic force microscopy are used to determine the size distributions and surface coverage of the NP film. We apply finite‐difference time‐domain techniques to model the optical properties of different nanoparticle films and compare this with the absorption properties of the organic active layer. The simulations demonstrate that the absorption and scattering efficiency of the particles are very sensitive to particle geometry. Solar cells prepared with window electrodes containing NP layers with less surface coverage, show a 14.8% improvement in efficiency. We discuss variations in the external quantum efficiency of the devices in terms of forward scattering and parasitic absorption losses induced by the NP layer. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)
The role of geographic distance in completing related acquisitions: Evidence from U.S. chemical manufacturers
Authors: Chakrabarti Abhirup , Mitchell Will
Published: February 2015

Acquisitions often do not reach completion when buyers' initial evaluations change during post‐announcement due diligence investigations, but research offers only limited explanations for when such deal‐cancelling new information will be most common. Drawing from the spatial geography and acquisition strategy literatures, we argue that successful completion of acquisitions can be partially explained by their spatial characteristics. We start by predicting that geographic distance has a particularly strong impact in reducing the likelihood of completing related acquisitions; we then identify contingencies based on multiple forms of direct, contextual, and vicarious experience that can help acquirers overcome the constraints of distance. We test the arguments with a sample of 1,603 domestic acquisitions announced by 724 U.S. chemical manufacturing firms between 1980 and 2004. Copyright © 2015 John Wiley & Sons, Ltd.
In‐Situ Study of Crystallization Behavior of a Mold Flux Using Single and Double Hot Thermocouple Technique
Authors: Yang Jian , Cui Yaru , Wang Lin , Sasaki Yasushi , Zhang Jianqiang , Ostrovski Oleg , Kashiwaya Yoshiaki
Published: February 2015

In this study, crystallization behavior of an industrial mold flux was investigated using both single hot thermocouple technique (SHTT) and double hot thermocouple technique (DHTT). Continuous cooling transformation (CCT) and time‐temperature transformation (TTT) diagrams were constructed using SHTT. The critical cooling rate in continuous cooling process was determined as 7 °C s−1 above which a glassy phase was formed. The TTT diagram showed two noses at approximately 1000 and 1075 °C. Phase identification carried out using X‐ray diffraction (XRD) revealed that dicalcium silicate (Ca2SiO4) was the major phase at both 950 and 1100 °C, together with minor precipitates of Na2CaSi3O8 and Ca2MgSi2O7 whose concentrations were relatively higher at 950 °C. Cuspidine (Ca4Si2O7F2) was also identified by XRD at 950 °C. Crystallization kinetics was analyzed using Johnson–Mehl–Avrami–Kolmogorov equation. DHTT was used to simulate the temperature gradient between copper mold and strand in the continuous casting mold. Glassy phase was formed quickly near the cold side when it was quenched from 1500 to 800 °C. Crystals started to precipitate in the glassy region after 48 s. Then major part of the glassy region was gradually transformed to crystalline phase and the crystals subsequently grew to the liquid region. A steady three‐layer state was reached after 360 s.
Conductance Calculation Of Slot Channels with Variable Cross Section
Authors: Burmistrov A. , Salikeev S. , Bronshtein M. , Fomina M. , Rayko A.
Published: February 2015

The range of operation pressures of non‐contact vacuum pumps may reach six decades, and flow regime in slot channels of the rotor mechanism may vary from molecular flow to viscous flow. This article is a continuation of a series of authors‘ publications dedicated to the development of a method which makes it possible to calculate promptly the conductance of slot channels with complex contoured geometry with the minimal clearance at a certain point along gas flow direction for all three gas flow regimes: molecular, transient and viscous.

The numerical solution of the differential equations system (equations of motion, energy, continuity and state) is used for calculation of mass flow rate in transient gas flow regime. On the basis of the numerical calculation results the relationship is obtained which represents a smooth joining of the data for molecular and viscous flow regimes.

Verification of the model and the obtained relationship is carried out by comparison of numerical calculation results of gas mass flow rate and conductance with experimental data obtained by blowing‐through of slot channels. The maximal deviation of calculation according to the obtained relationship from the experiment does not exceed 14%, the average uncertainty being less than 8%, which makes it possible to recommend it for practical application in transient flow regime.
Anti‐Eis‐Oberflächenbeschichtungen
Authors: Haupt Michael , Barz Jakob
Published: February 2015

Eis auf Oberflächen kann die Funktion von Bauteilen erheblich einschränken. Bildes sich Eis auf Flugzeugflügeln kann es im Winter sogar gefährlich werden. Ebenso ist die Eisbildung auf den Rotorblättern von Windenergieanlagen nicht erwünscht. Die Rotorblatter müssen dann beheizt werden um das Eis zu verhindern oder abzuschmelzen. Eis von Oberflächen zu entfernen kostet somit Energie. Das Fraunhofer IGB in Stuttgart hat zusammen mit Partnern eine neuartige Anti‐Eis‐Folie entwickelt, die auf große Flächen einfach aufzukleben ist. Die stoß‐, schlag‐ und kratzfesten Folien werden in einem Niederdruck‐Plasmaprozess funktionalisiert. Diese Folie beeinflusst die Eisbildung und vermindert die Eishaftung auf den Oberflächen erheblich. Mit dieser Folie können verschiedenste Oberflächen beklebt werden und es eröffnet sich ein breites Anwendungsfeld dieser Art von Beschichtung.
Development, Organisation and Implementation of a Surgical Skills ‘Boot Camp’: SIMweek
Authors: Singh Pritam , Aggarwal Rajesh , Pucher Philip H. , Darzi Ara
Published: February 2015

Background

There is evidence of increased mortality and reduced efficiency in hospitals due to the annual changeover of junior doctors. This paper describes a framework to develop an intensive simulated week that will recreate experiences and situations that junixor surgical interns will likely face in their first weeks after graduation.

Methods

To provide evidence‐based recommendations, a systematic review of published literature using the keywords ‘surg*’, ‘boot’, ‘camp’ was performed. Reports of the development, implementation or evaluation of a simulated skills course or ‘boot camp’ to prepare incoming surgical interns were analysed.

Results

Eighteen relevant articles were identified. Subjects on internship preparation courses have identified ‘hands‐on’ training sessions to be very useful. In particular, mock pages have been identified as being valuable and didactic lectures have been identified as the weakest parts of the course. We first consider the end‐users of the course and their associated learning needs. We subsequently discuss resources required and propose a strategy for the organisation of a course and selection of teaching faculty. Finally, we consider the costs involved in running a course.

Conclusions

This paper proposes a framework for the development, organisation and implementation of an intensive simulation course to prepare graduating medical students for their role as junior surgical intern. Facilitating the step change in responsibility from student to surgical intern may improve patient safety in addition to reducing the associated anxiety for the clinician.
Survival Outcome Between Hepatic Resection and Transarterial Embolization for Hepatocellular Carcinoma More Than 10 cm: A Propensity Score Model
Authors: Chan Yi‐Chia , Kabiling Catherine S. , Pillai Vinod G. , Aguilar Gustavo , Wang Chih‐Chi , Chen Chao‐Long
Published: February 2015

Background

Hepatocellular carcinoma (HCC) larger than ten cm belonging to Barcelona Clinic Liver Cancer (BCLC) stage B and C may benefit from hepatic resection (HR), compared to presently recommended management by transarterial chemoembolization and sorafenib, respectively. This study reviews survival outcomes in such patients treated at a tertiary level hospital in Taiwan, and compares survival advantage of surgical resection over embolization therapy using a statistically valid propensity scores matching model.

Methods

192 patients newly diagnosed with HCC ≥ 10 cm between 2005 and 2010, who had HR (n = 104) and transarterial embolization (TAE) (n = 88), were retrospectively studied. Thirty‐two patients in each group were selected by propensity scores matching model for comparison.

Results

Survival rates at 1, 3, and 5 years of patients in BCLC stage B who had HR and TAE were 78.5, 61.4, 54.2 % and 30, 12.9, 12.9 %, (p < 0.001), respectively. For stage C, survival rates were 77.8, 56.4, and 47 % at 1, 3, 5 years in HR group, while it was 12.7 % at 1 year in TAE group, (p < 0.001). Propensity score‐based analysis showed estimated 1‐, 3‐, and 5‐year survival rates of patients receiving HR and TAE were 90.2 versus 26.4 %, 64.3 versus 3.3 %, and 51.5 versus 3.3 %, respectively (p < 0.001).

Conclusions

HR had significantly better 5 year survival than TAE for patients with HCC ≥ 10 cm in the propensity score model. Overall survival of BCLC stage B may be improved by considering HR as first treatment option for resectable large HCCs, provided patient is fit for surgery with good liver remnant.
Infinite Measures on von Neumann Algebras
Authors: Goldstein Stanisław , Paszkiewicz Adam
Published: February 2015

Infinite measures on von Neumann algebras are classified according to properties analogous to those from classical measure theory. These properties are carefully examined in case of semifinite von Neumann algebras. Some examples are also given and the direction for further research indicated.
Hypothermic Oxygenated Liver Perfusion: Basic Mechanisms and Clinical Application
Authors: Schlegel A. , Kron P. , Dutkowski P.
Published: February 2015

Dynamic preservation strategies such as hypothermic machine perfusion are increasingly discussed to improve liver graft quality before transplantation. This review summarizes current knowledge of this perfusion technique for liver preservation. We discuss optimization of perfusion conditions and current strategies to assess graft quality during cold perfusion. Next, we provide an overview of possible pathways of protection from ischemia-reperfusion injury. Finally, we report on recent clinical applications of human hypothermic machine liver perfusion.