bluuebunny/crossref_metadata_2025_split huggingface dataset:
The crystal structure of the Y140F mutant of ADP‐L‐glycero‐D‐manno‐heptose 6‐epimerase bound to ADP‐β‐D‐mannose suggests a one base mechanism
Authors: Kowatz Thomas , Morrison James P. , Tanner Martin E. , Naismith James H. 
Published: May 2010

AbstractBacteria synthesize a wide array of unusual carbohydrate molecules, which they use in a variety of ways. The carbohydrate L‐glycero‐D‐manno‐heptose is an important component of lipopolysaccharide and is synthesized in a complex series of enzymatic steps. One step involves the epimerization at the C6″ position converting ADP‐D‐glycero‐D‐manno‐heptose into ADP‐L‐glycero‐D‐manno‐heptose. The enzyme responsible is a member of the short chain dehydrogenase superfamily, known as ADP‐L‐glycero‐D‐manno‐heptose 6‐epimerase (AGME). The structure of the enzyme was known but the arrangement of the catalytic site with respect to the substrate is unclear. We now report the structure of AGME bound to a substrate mimic, ADP‐β‐D‐mannose, which has the same stereochemical configuration as the substrate. The complex identifies the key residues and allows mechanistic insight into this novel enzyme.
Indoleamine 2,3‐dioxygenase (IDO) activity influence tumor growth in the TRAMP prostate cancer model
Authors: Källberg Eva , Wikström Pernilla , Bergh Anders , Ivars Fredrik , Leanderson Tomas 
Published: May 2010

AbstractBACKGROUNDIndoleamine 2,3‐dioxygenase (IDO) activity has been shown to be expressed in local lymph nodes and induce immune suppression of tumor immunity. Here we analyze the effect of IDO expression on prostate tumor growth using the transgenic adenocarcinoma of mouse prostate (TRAMP) animal model.METHODSMice deficient in IDO expression were crossed to TRAMP mice and the time to the appearance of palpable tumors were measured. Immune histology was used to analyze the IDO expressing cells in tumors and in local lymph nodes. The levels of the substrate for IDO (tryptophane) and its product (kynurenine) was measured by HPLC.RESULTSWe found that systemic IDO activity, determined as the kynurenine/tryptophan ratio in serum, correlated with the presence of palpable tumor. Immunohistological analysis showed increased numbers of IDO expressing cells in local lymph nodes. In tumors, IDO expression could be detected in the tumor stroma by both CD31+ and CD31− cells. Essentially no CD45+, IDO expressing cells could be detected in the tumors. The influence of IDO activity on tumor progression was analyzed by back‐crossing TRAMP mice with IDO−/− animals and J‐chain negative (J−/−) mice that have perturbed IDO activity. In both crosses a delayed tumor incidence was observed.CONCLUSIONOur results argue for a role for IDO mediated immune suppression in the early stages of prostate cancer progression. However, since the intra‐tumor IDO expression in J−/− mice was indistinguishable from that of C57BL/6 animals the IDO expression in the tumor tissue appears to be irrelevant for TRAMP tumor incidence. Prostate 70: 1461–1470, 2010. © 2010 Wiley‐Liss, Inc.
Muscarinic receptors and their mRNAs in type 2 Goto‐Kakizaki diabetic rat prostate
Authors: Saito Motoaki , Kazuyama Emi , Shimizu Shogo , Dimitriadis Fotios , Kinoshita Yukako , Masuda Eiji , Yamada Shizuo , Satoh Keisuke 
Published: May 2010

AbstractBACKGROUNDAs increasing evidence is pointing towards the relationship between diabetes and benign prostatic hyperplasia/lower urinary tract symptoms, we investigated the pharmacological properties and gene expressions of the muscarinic receptors in type 2 diabetes rat prostate.METHODSTwelve‐ and 70‐week‐old male Goto‐Kakizaki (GK) rats and age‐matched male Wistar rats were used in this study. The densities of muscarinic receptors (Bmaxvalues) were determined by saturation studies with [3H]NMS ([N‐methyl‐3H] scopolamine methyl chloride) in the prostatic membrane particulates. The participation levels of M1, M2, and M3receptor protein and mRNA levels in the prostate were investigated by immunoblot analysis and real‐time polymerase chain reaction (PCR), respectively.RESULTSThe Bmaxvalues in 12‐week‐old Wistar and GK, and in 70‐week‐old Wistar and GK rat prostates were 36.0 ± 2.8, 49.4 ± 11.4, 22.0 ± 2.2, and 47.0 ± 4.1 fmol/mg protein, respectively. However, there were no significant differences in the affinity constants between any groups. Immunoblot analysis showed the existence of significant amounts of M1, M2, and M3receptor subtypes in each rat prostate. According to real‐time PCR studies the rank order of expression levels of muscarinic receptors mRNA subtypes in the prostate were M3 > M2 > M1. In each receptor subtype in each group, diabetes induced up‐regulation of mRNAs while the advanced age of the rats was related with down‐regulation of mRNAs.CONCLUSIONSOur data indicated that type 2 diabetes induced up‐regulation and age‐related down‐regulation of the expressions of muscarinic receptors and their mRNAs in the rat prostate. Prostate 70: 1533–1539, 2010. © 2010 Wiley‐Liss, Inc.
Effect of high‐pressure food processing on the mass transfer properties of selected packaging materials
Authors: Galotto Maria Jose , Ulloa Pablo , Escobar Rodrigo , Guarda Abel , Gavara Rafael , Miltz Joseph 
Published: May 2010

AbstractThe effect of high‐pressure processing (HPP) on the total migration into distilled water and olive oil and on the barrier properties of four complex packaging materials were evaluated. The films were polyethylene/ethylene‐vinyl‐alcohol/polyethylene (PE/EVOH/PE), metallized polyester/polyethylene, polyester/polyethylene (PET/PE), and polypropylene‐SiOx (PPSiOx). Pouches made from these films were filled with food simulants, sealed and then processed at a pressure of 400 MPa for 30 min, at 20 or 60°C. Pouches kept at atmospheric pressure were used as controls. Prior to and after treatment, all films were evaluated for their barrier properties (oxygen transmission rate and water vapour transmission rate) and ‘Total’ migration into the two food simulants. In the case of water as the food stimulant, a low ‘Total’ migration was observed and even a lower one after the HPP treatment. In the case of oil as the food simulant, a higher ‘Total’ migration was found compared to the control as a result of damage to the structures during the HPP treatment. The gas permeability of the films increased after the HPP, compared to the control, due to damages in the structure caused during the treatment. The PET/PE film presented minimum changes in properties after HPP. Copyright © 2010 John Wiley & Sons, Ltd.
Assessment of technical and environmental performances of wheat‐based foams in thermal packaging applications
Authors: Wang Yong , Gao Yun‐Xin , Song Jim , Bonin Michael , Guo Miao , Murphy Richard 
Published: May 2010

AbstractThis paper presents an assessment of the technical and environmental performance of a wheat‐based foam (WBF) and bio‐composite for shipping chilled products. The thermal conductivity of the WBF was found to be higher than that of polyurethane foams commonly used in high‐value insulation packaging, but close to that of low‐density (expanded polystyrene) EPS foams and significantly lower than that of polyethylene (PE) foams, which are typically used in thermal packaging of foods. The insulation performance of a simple cool box constructed from both the WBF and EPS sandwich panels without the use of any refrigerant was studied experimentally. The comparison demonstrated that the performance of the WBF cool box was comparable to that of the EPS counterpart. Two industrial case studies were conducted on WBF cool boxes with refrigerants in comparison with PE or EPS counterparts. The WBF cool boxes had comparable thermal performance to the EPS and PE counterparts on the basis of identical foam thickness. The performance of the WBF cool boxes was also simulated with finite element (FE) modelling. Good agreement was achieved between experimental data and the FE prediction. The model was then used to assist cool box design. WBF cool boxes made from renewable raw materials are inherently biodegradable and may be used as an alternative to those based on polymer foams in thermal packaging applications. Life‐cycle assessment (LCA) was used to investigate environmental profiles of cool boxes made with WBF, EPS and PE foams. The WBF cool boxes offer substantially lower global warming and abiotic depletion potentials than equivalent cool boxes made from petrochemical foams. Copyright © 2010 John Wiley & Sons, Ltd.
Analytical description of a nocturnal low‐level jet
Authors: Shapiro Alan , Fedorovich Evgeni 
Published: May 2010

AbstractAn exact analytical solution of the equations of motion is presented for the Blackadar conceptual model of the nocturnal low‐level jet as an inertial oscillation arising from the sudden release of frictional constraint (near‐cessation of dry‐convective turbulent mixing) near sunset. The jet is modelled as a transient one‐dimensional boundary‐layer phenomenon, with the release of frictional constraint emulated by an impulsively reduced mixing coefficient (eddy viscosity). Prior to the reduction, the flow is in an equilibrium state described by the classical steady‐state Ekman solution. The dimensional parameters of the transient problem are the Coriolis parameter, the post‐ and pre‐sunset eddy viscosities, and an imposed pressure gradient force. The corresponding non‐dimensional problem is governed by a single parameter, the ratio of the post‐ and pre‐sunset mixing coefficients. The solution is obtained by the method of Laplace transforms. Copyright © 2010 Royal Meteorological Society
Desorption electrospray ionization mass spectrometric analysis of organophosphorus chemical warfare agents using ion mobility and tandem mass spectrometry
Authors: D'Agostino Paul A. , Chenier Claude L. 
Published: May 2010

AbstractDesorption electrospray ionization mass spectrometry (DESI‐MS) has been applied to the direct analysis of sample media for target chemicals, including chemical warfare agents (CWA), without the need for additional sample handling. During the present study, solid‐phase microextraction (SPME) fibers were used to sample the headspace above five organophosphorus CWA, O‐isopropyl methylphosphonofluoridate (sarin, GB), O‐pinacolyl methylphosphonofluoridate (soman, GD), O‐ethyl N,N‐dimethyl phosphoramidocyanidate (tabun, GA), O‐cyclohexyl methylphosphonofluoridate (cyclohexyl sarin, GF) and O‐ethyl S‐2‐diisopropylaminoethyl methyl phosphonothiolate (VX) spiked into glass headspace sampling vials. Following sampling, the SPME fibers were introduced directly into a modified ESI source, enabling rapid and safe DESI of the toxic compounds. A SYNAPT HDMS™ instrument was used to acquire time‐aligned parallel (TAP) fragmentation data, which provided both ion mobility and MSn (n = 2 or 3) data useful for the confirmation of CWA. Unique ion mobility profiles were acquired for each compound and characteristic product ions of the ion mobility separated ions were produced in the Triwave™ transfer collision region. Up to six full scanning MSn spectra, containing the [M + H]+ ion and up to seven diagnostic product ions, were acquired for each CWA during SPME fiber analysis. A rapid screening approach, based on the developed methodology, was applied to several typical forensic media, including Dacron sampling swabs spiked with 5 µg of CWA. Background interference was minimal and the spiked CWA were readily identified within one minute on the basis of the acquired ion mobility and mass spectrometric data. Copyright © 2010 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.
Characterization of protostane triterpenoids in Alisma orientalis by ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry
Authors: Liu Xin , Li Song‐Lin , Zhou Yan , Song Jing‐Zheng , Zheng Yun‐Feng , Peng Guo‐Ping , Xu Hong‐Xi 
Published: May 2010

AbstractA reliable and sensitive ultra‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry (UPLC/Q‐TOF‐MS) method has been optimized and established for analysis of protostane triterpenoids in a commonly used traditional Chinese herbal medicine Alisma orientalis (Sam.) Juzep. The separation of crude extract of A. orientalis was achieved on a Waters ACQUITY HSS T3 column (100 mm × 2.1 mm, 1.8 µm) eluting with 0.1% (v/v) formic acid/acetonitrile. A total of 20 protostane triterpenoids including 19 known compounds and a new one were well separated within 7 min. The collision‐induced dissociation (CID) tandem mass spectrometric (MS/MS) fragmentation patterns of protostane triterpenoids was firstly reported in this study. The hydrogen rearrangement at the C‐23‐OH leads to dissociation of the bond between C‐23 and C‐24 in the protostane triterpenoid skeleton during the CID process. This dissociation was the characteristic CID fragmentation pathway of this class of triterpenoids, and was useful for further differentiation of some positional isomers which contain an acetyl unit on the C‐23 or C‐24 position. The identities of isolated compounds were identified by comparing their retention times and CID fragmentation behaviors with those of reference standards or tentatively assigned by matching the empirical molecular formulae with those reported in the literature. It is concluded that this newly established UPLC/Q‐TOF‐MS method is a powerful approach for structural elucidation of protostane triterpenoids isolated from A. orientalis. Copyright © 2010 John Wiley & Sons, Ltd.
The relationship between the electrospray ionization behaviour and biological activity of some phosphino Cu(I) complexes
Authors: Tisato Francesco , Refosco Fiorenzo , Porchia Marina , Tegoni Matteo , Gandin Valentina , Marzano Cristina , Pellei Maura , Papini Grazia , Lucato Lara , Seraglia Roberta , Traldi Pietro 
Published: May 2010

AbstractElectrospray ionization mass spectrometry was usefully employed for the characterization of three phosphino copper(I) complexes of medicinal interest. This technique revealed that the original [CuL4]+ pro‐drugs (L = hydrophilic tertiary phosphine) underwent dissociation with production of coordinative unsaturated [CuL3]+ and [CuL2]+ species, which represented key intermediates for the activation of potential biological properties. The more favoured was the displacement of the ligands from the [CuL4]+ parent complex, the more favoured was in turn the possibility for the metal ion to directly interact with biological substrates, including pharmacological targets related to cancer proliferation. An inverse correlation between the stability and the cytotoxic activity of the three copper(I) complexes investigated has been clearly established. Copyright © 2010 John Wiley & Sons, Ltd.
Adaptive Naive Bayes method for masquerade detection
Authors: Dash Subrat Kumar , Reddy Krupa Sagar , Pujari Arun K. 
Published: May 2010

AbstractRecently, researchers have proposed efficient detection mechanisms for masquerade attacks. Most of these techniques use machine learning methods to learn the behavioral patterns of users and to check if an observed behavior conforms to the learnt behavior of a user. Masquerade attack is detected when the observed behavior, reportedly of a specific user, does not match with the learnt pattern of this user's past data. A major shortcoming in this process is that the user may legitimately deviate temporarily from its past behavior. If the deviation is large and near‐permanent, it is desirable that such deviations are captured in a detection mechanism. We propose, in this paper, a method that takes into consideration this aspect of user behavior while detecting masquerade attacks. Our scheme is based on the premise that the commands used by a legitimate user or an attacker may differ from the trained signature. But the deviation of the legitimate user is momentary whereas that of an attacker persists longer. By introducing this novel concept in the detection mechanism, the performance improves. We show this empirically using several benchmark datasets. Copyright © 2010 John Wiley & Sons, Ltd.
Protecting the integrity of trusted applications in mobile phone systems
Authors: Muthukumaran Divya , Schiffman Joshua , Hassan Mohamed , Sawani Anuj , Rao Vikhyath , Jaeger Trent 
Published: May 2010

AbstractMobile phones have evolved into indispensable devices that run many exciting applications that users can download from phone vendor's application stores. However, as it is not practical to fully vet all application code, users may download malware‐infected applications, which may steal or modify security‐critical data. In this paper, we propose a security architecture for phone systems that protects trusted applications from such downloaded code. Our architecture uses reference monitors in the operating system and user‐space services to enforce mandatory access control policies that express an approximation of Clark—Wilson integrity. In addition, we show how to justify the integrity of mobile phone applications by using the Policy Reduced Integrity Measurement Architecture (PRIMA), which enables a remote party to verify the integrity of applications running on a phone. We have implemented a prototype on the Openmoko Linux Platform, using an SELinux kernel with a PRIMA module and user‐space services that leverage the SELinux user‐level policy server. We find that the performance of enforcement and integrity measurement is satisfactory, and the SELinux reference policy can be reduced in size by 90% (although more reduction should be possible), enabling practical system integrity with a desirable usability model. Copyright © 2010 John Wiley & Sons, Ltd.
A formal model of trust for calculating the quality of X.509 certificate
Authors: Samer Wazan Ahmad , Romain Laborde , Francois Barrere , AbdelMalek Benzekri 
Published: May 2010

AbstractThe growing number of Public Key Infrastructure (PKI) and the increasing number of situations where partners of a transaction may carry certificates signed by different certification authority (CA) points out the problematic of trust between the different CAs. Several trust models, like the hierarchy model, cross‐certification model, and bridge CA model were proposed in order to establish and extend the domain of trust of relying parties (RP). However, each model has disadvantages and especially the scalability in large open networks like Internet. In this paper, we provide users with quantitative information of the confidence a relying party can have about a certificate. We call this information quality of certificate (QoCER). QoCER depends on two parameters which are the quality of procedures announced in the certificate policy (CP) and the quality of CA (QoCA) that represents the evaluation of the CA commitment to its policy. QoCA is calculated based on the recommendation of different actors (audit agency, RP, etc.). QoCER is balanced by another information that represents the confidence on QoCA calculation. We present a formal model of trust to calculate these values. Copyright © 2010 John Wiley & Sons, Ltd.
Photoemission study of methanol decomposition on Pt/Ni(111) surface alloy
Authors: Veltruská K. , Cabala M. , Libra J. , Skála T. , Tsud N. , Matolín V. 
Published: May 2010

AbstractPlatinum shows excellent catalytic activity in electrochemical oxidation of methanol. It is widely used in direct methanol fuel cells, but it is readily poisoned by CO‐like intermediates generated in methanol activation process. To increase Pt CO tolerance, oxophilic metals such as Ru or Ni are incorporated into Pt.In our model study we present results of the adsorption and decomposition of methanol on a Pt‐Ni ordered surface alloy prepared by Pt evaporation on Ni(111) surface, examined by conventional and synchrotron radiation XPS. Methanol adsorbed at low temperature formed adsorbate multilayers, which were consecutively desorbed upon heating to 600 K. Reaction intermediates arising during desorption were measured. Reaction pathways are discussed and compared with those obtained on a clean Ni(111) single crystal. Copyright © 2010 John Wiley & Sons, Ltd.
Optimal software maintenance policy considering unavailable time
Authors: Xiong Cheng‐Jie , Xie Min , Ng Szu‐Hui 
Published: May 2010

AbstractWith the enhancement of hardware and software engineering, the effectiveness and correctness of software is less and less doubted and customers are more aware about whether software services are available or not when needed. Software maintenance is one of the main reasons that make software unavailable and it is often very expensive to perform maintenance tasks. Common approaches of studying software maintenance are to consider it as a static by‐product of software operation and only the maintenance cost is covered. In this paper, software maintenance policies are studied with the consideration of unavailable service time. A non‐homogeneous continuous Markov chain is adopted for modeling the software operation and maintenance process, and the cost of software unavailability that is brought in by software maintenance is investigated and analyzed for searching the optimal maintenance policy, which aims at minimizing the average maintenance time cost. The optimality of our proposed policy is shown and checked by numerical examples with discussions of its possible application perspectives. Copyright © 2010 John Wiley & Sons, Ltd.
Aussteifung und Stabilisierung von Bauteilen und Tragwerken durch Sandwichelemente
Authors: Käpplein Saskia , Misiek Thomas , Ummenhofer Thomas 
Published: May 2010

AbstractWerden die systembedingten Besonderheiten beachtet, die sich aus dem hohen Vorfertigungsgrad der Bauelemente ergeben, lässt sich die hohe Steifigkeit von Sandwichelementen zur Aussteifung oder Stabilisierung nutzen. Der Stand der Technik in der Ermittlung der Steifigkeit und Tragfähigkeit von Sandwichelementen bei Beanspruchung als Scheibe wird vorgestellt. Der dominierende Einfluss der Verbindungen wird erläutert sowie aktuelle Entwicklungstendenzen aufgezeigt.Bracing and stabilisation by sandwich panels. The high in‐plane stiffness of sandwich panels can be taken into account for bracing (diaphragm action) or stabilisation (beams, columns) if the characteristics of such systems are taken into account. These characteristics are determined by the high degree of pre‐fabrication. The state of the art in the calculation of the stiffness and the load‐bearing capacity of sandwich panels under in‐plane loading is introduced. The dominating influence of the fixings is explained. Current development trends are identified.