bluuebunny/crossref_metadata_2025 huggingface dataset:
A dividing ratio changeable digital PLL based on phase state memory and double clock‐edge detection
Authors: Fujimoto Kuniaki , Sasaki Hirofumi , Yahara Mitsutoshi
Published: September 2010

In this paper, we propose a dividing ratio changeable digital phase‐locked loop (PLL) based on phase state memory and double clock‐edge detection that satisfies the three characteristics of low jitter, wide lock‐in range, and fast pull‐in at the same time. The counter for the double edge detection of the base clock reduces the circuit scale by using a selector. In the steady state, the output jitter of the proposed digital PLL is always a half pulse width of the base clock regardless of the frequency fluctuation of the base clock. Also, the upper bound frequency of the lock‐in range becomes six times that of the conventional dividing ratio changeable PLL, when the permissible output jitter is identical. Furthermore, the fast pull‐in is finished in one cycle of the input signal and the pulse width of the multiplication output signal becomes almost constant. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(9): 19–26, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10251
Recognition of devoiced vowels using optical microphone made of multiple POF moisture sensors
Authors: Morisawa Masayuki , Natori Yoichi , Taki Tomohito , Muto Shinzo
Published: September 2010

A novel optical fiber microphone system for recognizing devoiced vowels has been studied. This system consists of optical detection of the moisture pattern formed by a devoiced breath and its recognition by modified DP‐matching. To detect the moisture pattern of devoiced vowels, five plastic optical fiber moisture sensors with fast response were developed and used. Using this system, a high discernment rate of over 93% was obtained for devoiced vowels. This system will be used for verbally handicapped people to create sounds with minimal effort in the near future. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(9): 12–18, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ ecj.10253
Paper filtering method using features of coauthor research group, subject category, and terminology
Authors: Yamamoto Masao , Mase Hisao , Yajima Hiroshi , Kinukawa Hiroshi
Published: September 2010

A paper filtering system that supports the effective collection of related technical papers is becoming important as technological progress accelerates. Two requirements for the paper filtering system are (1) reduction of the user workload in specifying the filtering conditions and (2) sufficient filtering accuracy. We propose a paper filtering method that meets both requirements simultaneously by focusing on the features of the coauthor research group, subject category, and terminology. The result of evaluation using 3600 domestic learned‐society papers shows that the proposed method improved the mean average precision from 0.39 to 0.50, that is, by 0.11, compared with the conventional pseudo‐relevance feedback method, thus improving its suitability for practical use. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(9): 1–11, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10264
Consideration of direct bit‐rate measuring method based on extracting envelope signal
Authors: Otani Akihito , Tsuda Yukio , Igawa Koji , Shida Katsunori
Published: September 2010

We previously developed an optical sampling oscilloscope (EDT‐OSO) based on an envelope detection triggering method. This EDT‐OSO can stably measure eye‐diagram waveforms of signals exceeding 100 Gbps without an external high‐frequency clock signal. However, far‐end waveform measurements over a long distance could not be performed because the EDT‐OSO requires the linkage of 10‐MHz time bases in the EDT‐OSO and a light under test (LUT) generator for synchronizing. To overcome this drawback we developed a direct bit‐rate measuring method for synchronizing both 10‐MHz time bases virtually and a self‐synchronized EDT‐OSO (SSEDT‐OSO) based on this method. We confirmed that the bit‐rate measurement repeatability of the SSEDT‐OSO was from 10B9 to 10B8 by evaluating the standard deviation, and showed that the SSEDT‐OSO can measure an eye diagram without linking to 10‐MHz time bases. This paper explains the basic principle for measuring the bit‐rate of the LUT directly. We also describe the configuration of the SSEDT‐OSO and present evaluation results. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 173(4): 1–8, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21031
Voltage stability preventive control using VMPI sensitivities
Authors: Kataoka Yoshifumi , Watanabe Masato , Sakaeda Shingo , Iwamoto Shinichi
Published: September 2010

In power systems the proper voltage ranges are predetermined in the individual voltage classes. In order to maintain the proper voltage ranges, we propose the voltage stability index VMPI (Voltage Margin Proximity Index), which defines the voltage stability from the point of view of the voltage magnitude limits. Many previous papers dealing with voltage stability preventive control have used control devices which take continuous values, such as static var compensators, but real power systems mainly utilize voltage control devices which take discrete values. Hence, in this paper, we propose voltage stability preventive control using the VMPI sensitivities in order to control devices which take discrete values. We generally require speed for preventive control in order to use it on line, but the VMPI takes time due to the performance of optimal power flow calculations. Consequently, we propose a practical voltage stability preventive control method using a calculation with initial estimates of the control devices and estimation of the VMPI sensitivities, which requires less calculation time. Simulations using the IEEJ West 30‐machine 115‐bus system have verified the effectiveness of the proposed method. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 173(4): 28–37, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21033
Redox and Lewis Acid Reactivity of Unsaturated OsII
Authors: Tsvetkov Nikolay , Pink Maren , Fan Hongjun , Lee Joo‐Ho , Caulton Kenneth G.
Published: September 2010

A synthesis of [(PNP)OsI] {PNP = (tBu2PCH2SiMe2)2N} permits evaluation of its reactivity, both Lewis acidity and reducing power (i.e., ability to be oxidized). It binds two molecules of PhCN, into trans sites, but only one of ethylene, and, upon binding of one N2, there is heterolytic splitting of one tBu C–H bond to put the proton on amide N and the carbon on Os, leaving divalent metal in [{PN(H)P*}Os(N2)(I)]. Two moles of H2 add, forming [{PN(H)P}OsH(H2)I], via H–H bond heterolysis. Thermolysis of [(PNP)OsI] gives the product of adding a tBu methyl C–H bond across the Os/N bond, and also net dehydrogenation of this intermediate, forming a carbene complex; the released H2 forms [(PNP)OsH2I], and the chemistry of [(PNP)Os] hydridohalides is described. Reaction with O2 occurs with no detectable intermediate, to completely split the O=O bond, and form trans‐[(PNP)Os(O)2I], a product of four electron redox change. Attempted two electron oxidation by oxygen atom transfer with pyridine N‐oxide or Me3NO or N2O surprisingly effect transposition of N from its silyl substituents onto the metal, and replace N by O, forming a nitride complex of a bis(silyl ether, phosphane) chelate whose oxygen fails to bind to Os. The product is thus four‐coordinate, tetrahedral [(POP)Os(N)I], with an Os/N triple bond.
Biodegradation and utilization of waste cooking oil by Yarrowia lipolytica CECT 1240
Authors: Domínguez Alberto , Deive Francisco J. , Angeles Sanromán M. , Longo María A.
Published: September 2010

Biodegradation of waste cooking oil and its application as lipase production inducer in cultures of Yarrowia lipolytica CECT 1240 have been investigated, both in shake flasks and a bench‐scale bioreactor. The ability of this strain to degrade the spent oil was evaluated by monitoring COD throughout the cultures, and a remarkable decrease was recorded (almost 90% decrease in oil COD after 3 days in bioreactor). Moreover, the addition of waste cooking oil to the medium led to a significant augmentation in extracellular lipase production by the yeast, compared to oil‐free cultures. This confirms the suitability of the studied residue as an inducer of lipase biosynthesis, which is a very interesting fact, from an economic standpoint. These results were confirmed when a fed‐batch strategy was proposed. Finally, some properties of the crude enzyme were studied, and compared to the enzymes obtained when non‐used oil was added to the medium.

Practical application: New strategies to valorize wastes from the food and agro industries are attracting a great scientific interest due to the important advantages offered from an economic and environmental point of view. For this reason, the yeast Yarrowia lipolytica CECT 1240 is proposed for degrading waste cooking oils. This approach entails also another benefit in terms of lipolytic enzyme synthesis, since the addition of used up oils has a lipase inducer effect. The enormous interest in lipases is reflected in the number of applications that they present. The process was successfully carried out both in shake flasks and a bench‐scale bioreactor, allowing producing high levels of lipolytic activity at the same time that the COD was diminished up to nearly 90%.
Physico‐chemical composition, fractionated glycerides and fatty acid profile of chicken skin fat
Authors: Feddern Vivian , Kupski Larine , Cipolatti Eliane P. , Giacobbo Gregory , Mendes Gabriela L. , Badiale‐Furlong Eliana , de Souza‐Soares Leonor A.
Published: September 2010

Skin is one of the several co‐products of chicken meat industries, considered as waste, being rarely utilized or underutilized. Brazil is the world leader in chicken exports (3.6 million tons) and the third largest producer with 10.9 million tons, from which 440 000 ton/year are residues. This work aimes at characterizing chicken skin fat (CSF), comparing it with soybean oil, a well‐known and abundant compound, evaluating the physico‐chemical composition, fractionated glycerides and fatty acid profile, searching for CSF use in interesterification reactions. For that, determination of peroxide and p‐anisidine values, as well as thiobarbituric acid, iodine, saponification, acidity, unsaponified matter and refraction indexes were accomplished, besides the glycerides fractionation, followed by FAME derivatization and identification by GC. The nutritional quality indexes were calculated from the lipid profile. CSF showed satisfactory quality due to low acidity (0.65 g oleic acid/100 g), peroxide (2.14 meq/kg), p‐anisidine (0.70 absorbance units/g) values, besides presenting high proportion of MUFA (40%). However, due to CSF low hypocholesterolemic/hypercholesterolemic value (HH = 2.72), it may be difficult to use it for nutritional purposes the way it is found, once it tends to increase cholesterol. CSF it is a promising residue for different purposes including interesterification reactions and biodiesel production.
Physicochemical and rheological properties of passion fruit oil and its polyol
Authors: Lopes Roseany de Vasconcelos Vieira , Zamian José Roberto , Resck Ines Sabioni , Sales Maria José Araújo , dos Santos Maria Lucília , da Cunha Francisco Ricardo
Published: September 2010

Vegetable oils are excellent renewable sources for chemical and oleochemistry industries, since they can be functionalized to be used in various applications. Here we present some physical and physicochemical properties of passion fruit oil and polyol derivatives obtained from this oil. The polyols were obtained by hydroxylation with in situ generation of the performic acid. Physicochemical properties, such as chromatographic analysis, iodine value, index of acidity, peroxide index, fixation index, unsaponifiables, and hydroxyl index were determined according to standard methods. Furthermore, 1H NMR was examined and physical properties including liquid density and rheometry were characterized as well. The results revealed a wide variation of the physicochemical characteristics among the oils and respective polyols. The NMR analyses demonstrated polyol structures practically without unsaturation. The liquid rheology showed that the viscosity of polyols is at least two orders of magnitude larger than the viscosity of the original oil, confirming that the hydroxylation reaction occurred successfully. The shear viscosity of the polyols did not exhibit a systematic dependence on the shear rate or significant time dependence for the examined samples. The results indicate that the polyol viscosity decreases with the drying time increasing.

Practical applications: The use of renewable resources is growing and is attracting great interest in the academic and industrial fields. Vegetable oils have attracted a special attention because of their potential to replace petrochemical derivatives and to contribute to minimizing environmental impacts; vegetable oils are promising candidates for base fluids in environment‐friendly lubricants. Polyols obtained from oils open new possibilities of use as monomers for polyurethanes, which exhibit excellent properties beyond reactivity.
Evaluation of the antioxidant activity of vegetable oils based on luminol chemiluminescence in a microemulsion
Authors: Murillo Pulgarín José A. , Bermejo Luisa F. García , Durán Armando Carrasquero
Published: September 2010

A flow injection analysis (FIA) methodology has been developed for the estimation of the radical scavenging activity (RSA) of edible oils as a measure of their antioxidant activity. The RSA determination was based on the inhibition of the luminol chemiluminescence (CL) induced by the Fenton's reagent in a microemuslion (n‐hexane in water). At the optimum operational conditions, the RSA of gallic acid and buthylhydroxylanisol, usually employed as antioxidant in vegetable oils, as well as corn, sunflower, olive, soybean and sesame oils, were measured in terms of the IC50 (the concentration required to reduce in 50% the CL emission measured in the absence of antioxidants in the organic phase). For this purpose, the percentage of the CL inhibition (%Inh) against the sample concentration was plotting. Virgin oils of sesame and olive showed the greatest RSA, which was associated to their elevated concentration of natural antioxidants, such as phenols, tocopherols and lignans. The refined soybean oil also has an important antioxidant activity due to the addition of synthetic antioxidants after the refining process, while the lower RSA activities were found in the refined corn and sunflower oils. The results of the proposed method showed good agreement with those obtained by the DPPH test, which suggests that it could be used as a complementary method for the evaluation of hydrophobic substances with antioxidant properties.
Preparation of Imino Lactones by Electrophilic Cyclization of β,γ‐Unsaturated Hydroxamates: Formation of 3‐Cyanoprop‐2‐en‐1‐ones through Fragmentation Reactions
Authors: Trabulsi Houssam , Guillot Régis , Rousseau Gérard
Published: September 2010

Treatment of γ‐disubstituted β,γ‐unsaturated hydroxamates with bis(collidine)bromine(I) hexafluorophosphate led mainly to the formation of cyclic bromo imidates – the thermodynamic products. Unsaturated cyclic imidates were then obtained by treatment with triethylamine. With γ‐aryl β,γ‐unsaturated hydroxamates, the corresponding cyclic bromo imidates were also obtained. On treatment with triethylamine, however, these compounds led to the formation of 3‐cyanoprop‐2‐en‐1‐ones in good yields through fragmentation reactions.
Covalent versus Electrostatic Strategies for Nanoparticle Immobilisation
Authors: Mertens Stijn F. L. , Bütikofer Angela , Siffert Luca , Wandlowski Thomas
Published: September 2010

We demonstrate that in neutral electrolytes, a polyelectrolyte‐based (ω‐mercaptoacid/poly‐L‐lysine) immobilisation strategy for as‐prepared electrostatically stabilised metal nanoparticles is a powerful alternative to often difficult to control dithiol approaches. Our data confirm straightforward preparation of high‐coverage nanoparticle electrodes with fast kinetics and an electrochemical window of up to 1.5 V even in unbuffered solutions, under both stationary and hydrodynamic conditions. The stability region is limited by reductive desorption of the mercaptocarboxylic acid at negative potentials, and by nanoparticle oxidation at positive potentials. The electrostatic immobilisation is valuable for the study of electroanalytical and electrocatalytic processes using nanoparticulate electrode materials.
Chemometric methods for simultaneous quantification of lactic, malic and fumaric acids
Authors: Sokullu Esen , Palabıyık İsmail Murat , Onur Feyyaz , Boyacı İsmail Hakkı
Published: September 2010

Lactic, fumaric and malic acids are commonly used in food and pharmaceutical industries. During microbial production of these compounds, it is important to determine their concentrations in the fermentation broth with a rapid and sensitive method. Spectrophotometry is commonly used. However, UV‐spectral overlap between these organic acids makes it difficult to determine each of them individually from the mixture. In order to overcome this problem, statistical methods, namely principal component regression (PCR) and partial least squares‐1 methods, were tested and compared with conventional HPLC techniques. The absorbance data matrix was obtained by measuring the absorbances of 21 ternary mixtures of lactic, fumaric and malic acids in a wavelength range of 210–260 nm. Calibration and validation were performed by using the data obtained in a mixture of these organic acids. The prediction abilities of the methods were tested by applying them to fermentation broths. The precision of the PCR method was better than that of the partial least squares‐1 method. In the PCR method, the correlation coefficients between actual and predicted concentrations of the organic acids were calculated as 0.970 for lactic acid and 0.996 for fumaric acid in fermentation broths. The concentration of malic acid was not detected due to its low concentration in samples. These results show that the PCR method can be applied for simultaneous determination of lactic, fumaric and malic acids in fermentation broths.
Stirring and biomass starter influences the anaerobic digestion of different substrates for biogas production
Authors: Rojas Christian , Fang Sheng , Uhlenhut Frank , Borchert Axel , Stein Ingo , Schlaak Michael
Published: September 2010

Here, we present the results of lab‐scale experiments conducted in a batch mode to determine the biogas yield of lipid‐rich waste and corn silage under the effect of stirring. Further semi‐continuous experiments were carried out for the lipid‐rich waste with/without stirring. Additionally, it was analyzed how the starter used for the batch experiment influences the digestion process. The results showed a significant stirring effect on the anaerobic digestion only when seed sludge from a biogas plant was used as a starter. In this case, the experiments without stirring yielded only about 50% of the expected biogas for the investigated substrates. The addition of manure slurry to the batch reactor as part of the starter improved the biogas production. The more diluted media in the reactor allowed a better contact between the bacteria and the substrates making stirring not necessary.
Podophyllotoxin: Current approaches to its biotechnological production and future challenges
Authors: Yousefzadi Morteza , Sharifi Mozafar , Behmanesh Mehrdad , Moyano Elisabeth , Bonfill Mercedis , Cusido Rosa M. , Palazon Javier
Published: September 2010

Many plant‐derived agents are being used to treat cancer, including taxol, vinblastine, vincristine, or camptothecin and podophyllotoxin derivatives, among others. Plant biotechnology can provide a new tool for the production of anticancer agents but in spite of considerable efforts to produce vinblastine and vincristine in cell cultures and knowledge of the biosynthetic pathway of Catharanthus roseus alkaloids, the biotechnological production of taxol has only been achieved at an industrial level by companies such as Phyton Biotech and Cytoclonal Pharmaceutics. Podophyllotoxin was isolated as the active antitumor agent from the roots of Podophyllum species and more recently from the genus Linum and others. Etoposide, teniposide, and etophos are semi‐synthetic derivatives of podophyllotoxin and are used in the treatment of cancer. Biotechnological approaches, including the use of cell cultures, biotransformation, or metabolic engineering techniques to manipulate the biosynthetic pathway, represent an alternative for the production of podophyllotoxin and are discussed in this review.
Cheese whey as a renewable substrate for microbial lipid and biomass production by Zygomycetes
Authors: Vamvakaki Afroditi‐Nectaria , Kandarakis Ioannis , Kaminarides Stelios , Komaitis Michael , Papanikolaou Seraphim
Published: September 2010

Three Zygomycetes, Mortierella isabellina, Thamnidium elegans and Mucor sp., were tested for their ability of producing biomass and lipid‐containing γ‐linolenic acid (GLA) during their cultivation on cheese whey. M. isabellina consumed all of the available lactose and a significant amount of the available protein. On the contrary, the two other fungi seemed incapable of consuming lactose after protein exhaustion. In the second series of experiments, for M. isabellina a supplementary quantity of lactose was added into the medium in order to increase the C/N ratio and hence to increase the production of fat. In the case of T. elegans and Mucor sp., a supplementary quantity of ammonium sulfate was added in order to favor the consumption of lactose and the production of biomass. Indeed, enhancement of lipid production was observed for M. isabellina and biomass production for T. elegans and Mucor sp.. Fatty acid analysis of the microbial lipid showed a composition that presented non‐negligible changes in relation with the age of the culture and the C/N molar ratio of the medium. Further analysis of the fat showed that the quantity of neutral lipids was the more abundant. The fatty acid composition of neutral lipids resembled to that of total lipids. Phospholipids were the more unsaturated fraction for Mucor sp. and M. isabellina. GLA was synthesized in all trials but its concentration presented differences related with the utilized strains and the fermentation time. Growth of M. isabellina on lactose‐supplemented whey resulted in a maximum GLA production of 301 mg/L.
A ground motion prediction equation for JMA instrumental seismic intensity for shallow crustal earthquakes in active tectonic regimes
Authors: Campbell Kenneth W. , Bozorgnia Yousef
Published: September 2010

The JMA (Japan Meteorological Agency) seismic intensity scale has been used in Japan as a measure of earthquake ground shaking effects since 1949. It has traditionally been assessed after an earthquake based on the judgment of JMA officials. In 1996 the scale was revised as an instrumental seismic intensity measure (IJMA) that could be used to rapidly assess the expected damage after an earthquake without having to conduct a survey. Since its revision, Japanese researchers have developed several ground motion prediction equations (GMPEs) for IJMA using Japanese ground motion data. In this paper, we develop a new empirical GMPE for IJMA based on the strong motion database and functional forms used to develop similar GMPEs for peak response parameters as part of the PEER (Pacific Earthquake Engineering Research Center) Next Generation Attenuation (NGA) project. We consider this relationship to be valid for shallow crustal earthquakes in active tectonic regimes for moment magnitudes (M) ranging from 5.0 up to 7.5–8.5 (depending on fault mechanism) and rupture distances ranging from 0 to 200 km. A comparison of this GMPE with relationships developed by Japanese researchers for crustal and shallow subduction earthquakes shows relatively good agreement among all of the relationships at M 7.0 but relatively poor agreement at small magnitudes. Our GMPE predicts the highest intensities at small magnitudes, which together with research on other ground motion parameters, indicates that it provides conservative or upwardly biased estimates of IJMA for M<5.5. Copyright © 2010 John Wiley & Sons, Ltd.
Potential of superelastic Cu–Al–Mn alloy bars for seismic applications
Authors: Araki Y. , Endo T. , Omori T. , Sutou Y. , Koetaka Y. , Kainuma R. , Ishida K.
Published: September 2010

We present the results of the quasi‐static cyclic tensile tests of Cu–Al–Mn shape memory alloy (SMA) bars of 4 and 8 mm diameters to examine their superelasticity and other mechanical properties closely related to seismic applications. The present Cu–Al–Mn SMA bars have achieved the recovery strains of over 8% and the fracture strains of over 17%. Low‐cycle fatigue was observed in neither of the bars. The mechanical properties obtained from the test, along with the lower material cost and higher machinability than Ni–Ti SMAs, demonstrate the high potential of the present Cu–Al–Mn SMA bars to be used in seismic applications. Copyright © 2010 John Wiley & Sons, Ltd.
Seismic resistance capacity of beam–column connections in high‐rise buildings: E‐Defense shaking table test
Authors: Chung Yu‐Lin , Nagae Takuya , Matsumiya Tomohiro , Nakashima Masayoshi
Published: September 2010

A series of E‐Defense shaking table tests are conducted on a large‐scale test specimen that represents a high‐rise steel building. Two types of connections featuring the connection details commonly used in 1970s, in the early days of high‐rise construction in Japan, are adopted: the field‐welded connection consisting of welded unreinforced flanges and a bolted web type, and the shop‐welded connection in which the flanges and web are all‐welded to the column flange in the shop. To examine the seismic capacity of a total of 24 beam‐to‐column connections of the specimen, particularly when it is subjected to long‐period ground motion characterized not so much by large amplitude as by very many cycles of repeated loading, the test specimen is shaken repeatedly until the connections fractured. The test results indicate that a few of the field‐welded connections fractured from the bottom flange weld boundary in a relatively small cumulative rotation primarily due to the difficulties in ensuring the welding and inspection performance in the actual field welding. The shop‐welded connections are able to sustain many cycles of plastic rotation, with an averaged cumulative plastic rotation of 0.86 rad. Two shop‐welded connections exhibit ductile fractures but only after experiencing many cycles. The presence of RC floor slabs promotes the strain concentration at the toe of the weld access hole in the bottom flange by at least twice compared with the case without the slab, which had resulted in a decrease in the cumulative plastic rotation by about 50%. Copyright © 2010 John Wiley & Sons, Ltd.
Implementation of a second‐order paraxial boundary condition for a water‐saturated layered half‐space in plane strain
Authors: Lee Jin Ho , Kim Jae Kwan , Tassoulas John L.
Published: September 2010

A half‐space finite element and a transmitting boundary are developed for a water‐saturated layered half‐space using a paraxial boundary condition. The exact dynamic stiffness of a half‐space in plane strain is derived and a second‐order paraxial approximation of the stiffness is obtained. A half‐space finite element and a transmitting boundary are then formulated. The development is verified by comparison of the dynamic stiffness of impermeable and permeable rigid strip foundations with other published results. The advantage of using the paraxial boundary condition in comparison with the rigid boundary condition is examined. It is shown that the paraxial boundary condition offers significant gain and the resulting half‐space finite element and transmitting boundary can represent the effects of a water‐saturated layered half‐space with good accuracy and efficiency. In addition, the numerical method described herein maintains the strengths and advantages of the finite element method and can be easily applied to demanding problems of soil–structure interaction in a water‐saturated layered half‐space. Copyright © 2010 John Wiley & Sons, Ltd.
On the rate of convergence of binomial Greeks
Authors: Chung San‐Lin , Hung Weifeng , Lee Han‐Hsing , Shih Pai‐Ta
Published: September 2010

This study investigates the convergence patterns and the rates of convergence of binomial Greeks for the CRR model and several smooth price convergence models in the literature, including the binomial Black–Scholes (BBS) model of Broadie M and Detemple J (1996), the flexible binomial model (FB) of Tian YS (1999), the smoothed payoff (SPF) approach of Heston S and Zhou G (2000), the GCRR‐XPC models of Chung SL and Shih PT (2007), the modified FB‐XPC model, and the modified GCRR‐FT model. We prove that the rate of convergence of the CRR model for computing deltas and gammas is of order O(1/n), with a quadratic error term relating to the position of the final nodes around the strike price. Moreover, most smooth price convergence models generate deltas and gammas with monotonic and smooth convergence with order O(1/n). Thus, one can apply an extrapolation formula to enhance their accuracy. The numerical results show that placing the strike price at the center of the tree seems to enhance the accuracy substantially. Among all the binomial models considered in this study, the FB‐XPC and the GCRR‐XPC model with a two‐point extrapolation are the most efficient methods to compute Greeks. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark
Protein phosphatases 1 and 2A are both required for long‐term depression and associated dephosphorylation of cAMP response element binding protein in hippocampal area CA1 in vivo
Authors: Mauna Jocelyn C. , Miyamae Takeaki , Pulli Benjamin , Thiels Edda
Published: September 2010

Evidence shows that the serine/threonine protein phosphatase 1 (PP1) plays a critical role in synaptic plasticity and memory. Little is known about the contribution of the serine/threonine phosphatase 1 (PP2A) to synaptic plasticity. Both protein phosphatases can target the transcription factor cAMP response element binding protein (CREB), whose phosphorylation at Ser133, we previously found, was downregulated during long‐term depression (LTD) of glutamatergic transmission in area CA1 of the adult hippocampus in vivo. Other work from our group showed that the activity of PP2A, as well as that of PP1, is increased after LTD induction in area CA1 in vivo. We therefore investigated here whether both protein phosphatases are necessary for LTD in area CA1, and whether they both are involved in the LTD‐associated modification of CREB. We found that inhibition of either PP1 or PP2A interferes with the establishment of LTD. Furthermore, inhibition of either enzyme alone abrogated the LTD‐associated dephosphorylation of CREB. Interestingly, inhibition of PP1 disrupted CREB dephosphosphorylation rapidly after LTD‐inducing stimulation, whereas inhibition of PP2A did not blunt the CREB modification until a later time point. Thus, both PP1 and PP2A regulate CREB during LTD in area CA1, although possibly through different signaling pathways. Our results demonstrate that PP2A, similar to PP1, plays an essential role in the molecular events that underlie LTD at glutamatergic synapses in hippocampal area CA1 in vivo. We propose that one of the mechanisms through which these protein phosphatases may contribute to the prolonged maintenance of LTD is through the regulation of CREB. © 2010 Wiley‐Liss, Inc.
A simple expression for the bulk field capacity of a sloping soil horizon
Authors: Soulis E. D. , Craig J. R. , Fortin V. , Liu G.
Published: September 2010

Field capacity is a commonly used soil parameter in surface water hydrological models, loosely defined as the moisture content of a soil after drainage. The most commonly applied expression for field capacity is defined as the remaining water in a vertical soil column subject to 1/3 atm. of pressure head. While this quantification is sufficient in some cases, the definition is not consistent with the use of bulk field capacity in calculations of lateral drainage from hillslopes, as required by some surface soil parameterizations, nor does it address additional complications arising from differences in soil texture or sample size. Here, a simple alternative expression for bulk field capacity in a sloping or vertical soil is derived directly from Richards equation with the use of the Brooks‐Corey characteristics. It is demonstrated that this expression is consistent with data acquired from vertical soil columns, but may be extended to additional situations commonly found in surface water models and land surface schemes. The calculation of bulk field capacity requires only the Brooks‐Corey pore size distribution index, soil air‐entry pressure, and hillslope length and slope, and may be considered a physically based alternative to pedotransfer function or lookup table approaches. Copyright © 2010 John Wiley & Sons Ltd and Crown in the right of Canada.
Depth‐dependent hydraulic conductivity distribution patterns of a streambed
Authors: Chen Xunhong
Published: September 2010

Characterization of streambed hydraulic conductivity from the channel surface to a great depth below the channel surface can provide needed information for the determination of stream‐aquifer hydrologic connectedness, and it is also important to river restoration. However, knowledge on the streambed hydraulic conductivity for sediments 1 m below the channel surface is scarce. This study describes a method that was used to determine the distribution patterns of streambed hydraulic conductivity for sediments from channel surface to a depth of 15 m below. The method includes Geoprobe's direct‐push techniques and Permeameter tests. Direct‐push techniques were used to generate the electrical conductivity (EC) logs and to collect sequences of continuous sediment cores from river channels, as well as from the alluvial aquifer connected to the river. Permeameter tests on these sediment cores give the profiles of vertical hydraulic conductivity (Kv) of the channel sediments and the aquifer materials. This method was applied to produce Kv profiles for a streambed and an alluvial aquifer in the Platte River Valley of Nebraska, USA. Comparison and statistical analysis of the Kv profiles from the river channel and from the proximate alluvial aquifer indicates a special pattern of Kv in the channel sediments. This depth‐dependent pattern of Kv distribution for the channel sediments is considered to be produced by hyporheic processes. This Kv‐distribution pattern implied that the effect of hyporheic processes on streambed hydraulic conductivity can reach the sediments about 9 m below the channel surface. Copyright © 2010 John Wiley & Sons, Ltd.
Prospective assessment of quality of life in long‐term ovarian cancer survivors
Authors: Greimel Elfriede , Daghofer Fedor , Petru Edgar
Published: September 2010

The objective of our study was to compare prospectively the QoL in long‐term ovarian cancer survivors with short‐term survivors and to explore discriminating variables between short‐term and long‐term survival. Thirty‐three patients were included, 22 died within 5 years post diagnosis and 11 survived beyond 10 years. QoL data were collected pre‐treatment (baseline), 1‐year post diagnoses and for long‐term survivors 10 years post‐treatment using the EORTC QLQ‐C30. At baseline, there was no difference in terms of FIGO stage, residual tumor and adjuvant chemotherapy. Significantly, more short‐term survivors (96%) had intra operative ascites as compared to long‐term survivors (55%) (p=0.01). Before treatment, short‐term survivors had clinically significantly lower QoL scores on the physical functioning (mean 75.45) and role functioning scale (mean 68.94) compared to long‐term survivors (mean 68.94 and 84.85, respectively). They also reported higher levels of symptoms. One year post‐diagnosis, QoL scores were comparable in most domains. Long‐term survivors had a significantly better global QoL but more insomnia. Emotional functioning and global QoL/health status improved significantly from baseline to 1‐year post‐diagnosis and remained relatively stable at the 10‐year follow‐up. The presence of intra operative ascites and a supporting social network were identified as significant variables that discriminated between short‐term and long‐term survival. Compared to a reference sample, long‐term survivors showed similar QoL scores but more dyspnoea. Although ovarian cancer patients do not belong to the most prevalent survivor populations, we found that long‐term survivors have QoL scores similar to females without a history of cancer.
OCT4B1, a novel spliced variant of OCT4, is highly expressed in gastric cancer and acts as an antiapoptotic factor
Authors: Asadi Malek H. , Mowla Seyed J. , Fathi Fardin , Aleyasin Ahmad , Asadzadeh Jamshid , Atlasi Yaser
Published: September 2010

The octamer‐binding transcription factor 4 (OCT4) is involved in regulating pluripotency and self‐renewal maintenance of embryonic stem cells. Recently, misexpression of OCT4 has been also reported in some adult stem as well as cancer cells; a finding which is still controversial. In addition to the previously described spliced variants of the gene (e.g., OCT4A and OCT4B), we have recently identified a novel variant of the gene, designated as OCT4‐B1. In this study, we investigated a potential expression and function of OCT4B1 in a series of gastric cancer tissues and a gastric adenocarcinoma cell line, AGS. Using the Taqman real‐time PCR approach, we have detected the expression of OCT4B1 in tumors with no or much lower expression in marginal samples of the same patients (p < 0.002). We have also analyzed the effects of OCT4B1 knock‐down in AGS cell line treated with specific siRNA directed toward OCT4B1. Our data revealed that interfering with the expression of OCT4B1 caused profound changes in the morphology and cell cycle distribution of the cells. Furthermore, down‐regulation of OCT4B1 significantly elevated the relative activity of caspase‐3/caspase‐7 and the rate of apoptosis in the cells (more than 30%). All together, our findings suggest that OCT4B1 has a potential role in tumorigenesis of gastric cancer and candidates the variant as a new tumor marker with potential value in diagnosis and treatment of gastric cancer.
Integrated genetic and epigenetic analysis of bladder cancer reveals an additive diagnostic value of FGFR3 mutations and hypermethylation events
Authors: Serizawa Reza R. , Ralfkiær Ulrik , Steven Kenneth , Lam Gitte W. , Schmiedel Sven , Schüz Joachim , Hansen Alastair B. , Horn Thomas , Guldberg Per
Published: September 2010

The bladder cancer genome harbors numerous oncogenic mutations and aberrantly methylated gene promoters. The aim of our study was to generate a profile of these alterations and investigate their use as biomarkers in urine sediments for noninvasive detection of bladder cancer. We systematically screened FGFR3, PIK3CA, TP53, HRAS, NRAS and KRAS for mutations and quantitatively assessed the methylation status of APC, ARF, DBC1, INK4A, RARB, RASSF1A, SFRP1, SFRP2, SFRP4, SFRP5 and WIF1 in a prospective series of tumor biopsies (N = 105) and urine samples (N = 113) from 118 bladder tumor patients. We also analyzed urine samples from 33 patients with noncancerous urinary lesions. A total of 95 oncogenic mutations and 189 hypermethylation events were detected in the 105 tumor biopsies. The total panel of markers provided a sensitivity of 93%, whereas mutation and methylation markers alone provided sensitivities of 72% and 70%, respectively. In urine samples, the sensitivity was 70% for all markers, 50% for mutation markers and 52% for methylation markers. FGFR3 mutations occurred more frequently in tumors with no methylation events than in tumors with one or more methylation events (78% vs. 33%; p < 0.0001). FGFR3 mutation in combination with three methylation markers (APC, RASSF1A and SFRP2) provided a sensitivity of 90% in tumors and 62% in urine with 100% specificity. These results suggest an inverse correlation between FGFR3 mutations and hypermethylation events, which may be used to improve noninvasive, DNA‐based detection of bladder cancer.
Assessing the temporal variation of macroeconomic forecasts by a panel of changing composition
Authors: Engelberg Joseph , Manski Charles F. , Williams Jared
Published: September 2010

This paper calls attention to the problem of changing panel composition in surveys of forecasters and documents the problem in the Survey of Professional Forecasters. To study the temporal variation of forecasts, we recommend analysis of the time series of predictions made by individual forecasters. This makes transparent the heterogeneity of the panel and avoids improper inferences due to changing panel composition. In the absence of knowledge of the process determining panel composition, we warn against the traditional practice of aggregate time series analysis, which conflates changes in the expectations of individual forecasters with changes in the composition of the panel. Should analysis of aggregated predictions be thought desirable as a simplifying device, we recommend analyses of sub‐panels of fixed composition. Copyright © 2010 John Wiley & Sons, Ltd.
Crosstalk of osteoblast and osteoclast precursors on mineralized collagen—towards an in vitro model for bone remodeling
Authors: Bernhardt A. , Thieme S. , Domaschke H. , Springer A. , Rösen‐Wolff A. , Gelinsky M.
Published: September 2010

Bone remodeling and, therefore, integration of implant materials require the coordinated regulation of osteoblast and osteoclast activity. This is why the in vitro evaluation of biomaterials for bone regeneration should involve not only the analysis of osteoblast differentiation but also the formation and differentiation of osteoclasts. In the present study, we applied a material made of mineralized collagen I that mimics extracellular bone matrix to establish a culture system, which allows the cocultivation of human monocytes and human mesenchymal stem cells (hMSCs), which were differentiated into osteoclast‐like cells and osteoblasts, respectively. Both cell types were cultivated on membrane‐like structures from mineralized collagen. Transwell inserts were used to spatially separate the cell types but allowed exchange of soluble factors. The osteoclastogenesis and osteogenic differentiation were evaluated by analysis of gene expression, determination of alkaline phosphatase (ALP), and tartrate‐resistant acidic phosphatase (TRAP) activity. Furthermore, cell morphology was studied using scanning electron and transmission electron microscopy. Osteogenically induced hMSC showed an increased specific ALP activity as well as increased gene expression of gene coding for alkaline phosphatase (ALPL), when cocultivated with differentiating osteoclasts. Adipogenic differentiation of hMSCs was suppressed by the presence of osteoclasts as indicated by a major decrease in adipocyte cell number and a decrease in gene expression of adipogenic markers. The formation of multinucleated osteoclasts seems to be decreased in the presence of osteogenically induced hMSC as indicated by electron microscopic evaluation and determination of TRAP activity. However, gene expression of osteoclast markers was not decreased in coculture with osteogenically induced hMSC. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
The effect of surface topography on early NFκB signaling in macrophages
Authors: Waterfield J. Douglas , Ali Tarek A. , Nahid Fatemeh , Kusano Karu , Brunette Donald M.
Published: September 2010

Surface topography modulates macrophage expression of pro‐inflammatory cytokines through triggering of a number of different signaling pathways. In this article, we investigated the early activation of the NFκB pathway in RAW 264.7 macrophages in response to four surface topographies: mechanically polished (PO), coarse sand blasted (CB), acid etched (AE), and sandblasted and acid etched (SLA). We found that activation of the NFκB pathway was topography dependent. The PO and CB surfaces showed the highest level of activation, followed by the AE, then the SLA. Addition of suboptimal stimulatory concentrations of lipopolysaccharide (LPS) enhanced the response. Second, we determined that topography dependent cell signaling occurred in the absence of fetal bovine sera in the media. Third, we demonstrated that disruption of the lipid rafts by removal of cholesterol from cells in suspension using methyl β cyclodextrin (MβCD) affected signaling through the NFκB pathway and transcription of the pro‐inflammatory cytokine IL‐1 β, but did not affect cell adhesion, spreading or morphology. The number of macrophages adhered to the surfaces after 30 min followed the order PO, CB, AE, and SLA. In conclusion, our study suggests that one mechanism by which surface topography modulates activation of the NFκB pathway is through cholesterol‐enriched raft‐associated adhesive/signaling structures. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Long‐bone critical‐size defects treated with tissue‐engineered polycaprolactone‐co‐lactide scaffolds: A pilot study on rats
Authors: Rentsch Claudia , Rentsch Barbe , Breier Annette , Spekl Kathrin , Jung Roland , Manthey Suzanne , Scharnweber Dieter , Zwipp Hans , Biewener Achim
Published: September 2010

The aim of this study was to evaluate the osteogenic potential of embroidered, tissue‐engineered polycaprolactone‐co‐lactide (trade name: PCL) scaffolds for the reconstruction of large bone defects. Ten piled‐up PCL scaffolds were implanted in femura with a critical size defect of immunodeficient nude rats for 12 weeks [n = 4, group 1: noncoated, group 2: collagen I (coll I), group 3: collagen I/chondroitin sulfate (coll I/CS), and group 4: collagen I/chondroitin sulfate/human mesenchymal stem cells (coll I/CS/hMSC)]. X‐ray examination, computer tomography, and histological analyses of the explanted scaffold pads were performed. The quantification of the bone volume ratio showed a significantly higher rate of new bone formation at coll I/CS‐coated scaffolds compared with the other groups. Histological investigations revealed that the defect reconstruction started from the peripheral bone ends and incorporated into the scaffold material. Additionally seeded hMSC on coll I/CS‐coated scaffolds showed a higher matrix deposition inside the implant but no higher bone formation was observed. These data imply that the coll I/CS‐coated PCL scaffolds have the highest potential for treating critical size defects. The scaffolds, being variable in size and structure, can be adapted to any bone defect. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.