bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rheology of a Polymer‐Based Hybrid Suspension Composed of Concentrated Poly[(D,L‐lactide)‐co‐glycolide] Solution and Inorganic Salt Particles
Authors: Jing Dianying , Ding Jiandong 
Published: August 2007

AbstractSuspensions composed of a solution of a biodegradable polyester in a volatile organic solvent, and solid inorganic particles of size in the order of hundreds of microns have been very important in the fabrication of porous scaffolds in the field of tissue engineering. This article reports the basic rheological investigations of this complex fluid type. A Couette geometry covered by silicon oil was found to be an appropriate geometry to retain stability of the rheological measurements. Suspension viscosity increased with the particle volume fraction, and the extent of the increase was much larger than that predicted by the Einstein suspension equation. Both start‐up dynamics at the inception of steady shear and relaxation after an abrupt change of oscillatory shear frequency in the suspension showed significantly different behaviors from those in the associated polymer solution. Particle reorganization upon change of rheological state was anticipated.magnified image
Does santa have a great job? Gift shopping value and satisfaction
Authors: Babin Barry J. , Gonzalez Christine , Watts Christina 
Published: August 2007

AbstractFor good or bad, shopping and gifting are intertwined. This research looks at sources of gratification associated with shopping for gifts. More particularly, the roles played by general and specific shopping orientations in shaping gift shopping value and satisfaction are examined. Results from testing a theoretical model suggest that gift shopping orientations, such as agape, may dominate general shopping orientations, such as price consciousness. Also, the important role played by utilitarian shopping value is consistent with gift shopping more as a job than as a source of leisure. However, the results fall short of suggesting a negative relationship between gift shopping and hedonic shopping value. So gift shopping may be a job, but a job that is not so horrible after all. © 2007 Wiley Periodicals, Inc.
Natural and Synthetic Polyampholytes, 2
Authors: Kudaibergenov Sarkyt E. , Ciferri Alberto 
Published: August 2007

AbstractThe ability of natural and synthetic polyampholytes to exist in globular, coil, helix, stretched, and ordered conformations is reviewed and transformations and transitions between the respective states upon variation of conditions are highlighted. The properties of polyampholytes in solution, condensed, and gel state as well as at various interfaces are discussed in order to clarify the principles of the structural organization of proteins, model the function of biomembranes, and study the biocompatibility of modified materials. Application aspects of polyampholytes in protein separation, desalination, catalysis, the oil industry, biotechnology, nanotechnology, and medicine are given.magnified image
A Fourier–Karhunen–Loève discretization scheme for stationary random material properties in SFEM
Authors: Li C. F. , Feng Y. T. , Owen D. R. J. , Li D. F. , Davis I. M. 
Published: August 2007

AbstractIn order to overcome the computational difficulties in Karhunen–Loève (K–L) expansions of stationary random material properties in stochastic finite element method (SFEM) analysis, a Fourier–Karhunen–Loève (F–K–L) discretization scheme is developed in this paper, by following the harmonic essence of stationary random material properties and solving a series of specific technical challenges encountered in its development. Three numerical examples are employed to investigate the overall performance of the new discretization scheme and to demonstrate its use in practical SFEM simulations. The proposed F–K–L discretization scheme exhibits a number of advantages over the widely used K–L expansion scheme based on FE meshes, including better computational efficiency in terms of memory and CPU time, convenient a priori error‐control mechanism, better approximation accuracy of random material properties, explicit methods for predicting the associated eigenvalue decay speed and geometrical compatibility for random medium bodies of different shapes. Copyright © 2007 John Wiley & Sons, Ltd.
Direct chemiluminescent imaging detection of human serum proteins in two‐dimensional polyacrylamide gel electrophoresis
Authors: Tao Qian , Wang Zhenzhen , Zhao Heping , Baeyens Willy R. G. , Delanghe Joris R. , Huang Lingyun , Ouyang Jin , He Dacheng , Zhang Xianhua 
Published: August 2007

AbstractA novel chemiluminescence (CL)‐based imaging method capable of directly detecting proteins in polyacrylamide gels after electrophoresis is proposed. Human serum proteins are presently detected by a direct CL imaging method after native 2‐D PAGE. As a consequence, some proteins, including haptoglobin (Hp), Hp precursor, hemopexin (Hpx) precursor, Ig alpha‐1 chain C region, and Complement C3 precursor can be detected and identified by MS and MS/MS techniques. These proteins are all acute phase proteins, which have been defined as biomarkers for certain diseases. Moreover, serum proteins from healthy people and cirrhotic patients were analyzed. A decrease in Hp spots for cirrhotic patients could be confirmed. The CL imaging conditions were optimized, including the concentrations of H2O2 and luminol. The process of CL detection of proteins is simple, and there is no need for specialized equipment. In comparison with the traditional CBB‐R250 staining method, the detection sensitivity was improved and the detection period decreased about 70 times. Hence, this technique possesses potentials as a rapid, convenient, and inexpensive analytical technique for protein detection and for the diagnosis of diseases.
Rap2 regulates androgen sensitivity in human prostate cancer cells
Authors: Bigler Dora , Gioeli Daniel , Conaway Mark R. , Weber Michael J. , Theodorescu Dan 
Published: August 2007

AbstractBACKGROUNDProgression of prostate cancer to a fatal androgen‐independent disease is associated with activation of MAP kinase, consistent with chronic stimulation of the Ras‐signaling pathway. We have previously shown that Ras activation is sufficient to induce androgen‐independent growth of prostate cancer cells. One mechanism of MAP kinase regulation is modulation of Ras signaling by other Ras family members, the Rap gene paralogs Rap1a/b and Rap2a/b. Here we ask if Rap proteins play a role in determining androgen sensitivity of human prostate cancer cells either alone or in the context of an activated Ras.METHODSTo evaluate the role of Rap proteins in androgen responsiveness we use Rap over‐expression with or without mutated Ras co‐transfection and Rap siRNA knockdown to evaluate androgen‐dependent prostate‐specific antigen (PSA) promoter reporter expression and cell growth in androgen‐dependent LNCaP and independent C4‐2 human prostate cancer cells.RESULTSRap1 is equally expressed between LNCaP and C4‐2 cells and thus we focused on Rap2 which is minimally expressed in C4‐2. Rap2a affects androgen‐dependent PSA reporter expression in a dose‐dependent manner in LNCaP and C4‐2 cells. Low levels of Rap2a enhance PSA reporter expression, whereas higher concentrations inhibit expression. We show that Rap2a antagonizes the enhanced PSA reporter expression conferred by an active RasV12 gene in prostate cancer cells. siRNA knockdown data indicate that Rap2 has a greater effect on androgen‐stimulated growth in LNCaP than in C4‐2 cells.CONCLUSIONSWe show that Rap2 is involved in androgen‐mediated transcriptional and growth responses of human prostate cancer cells. Prostate 67: 1590–1599, 2007. © 2007 Wiley‐Liss, Inc.
Integrated self‐aligned conjugated polymer fiber laser devices
Authors: Gaal Martin , List Emil J. W. 
Published: August 2007

AbstractIn this letter we present a fully integrated self‐aligned distributed feedback (DFB) fiber laser device, which was directly imprinted in the conjugated polymer poly[2‐methoxy‐5 (2‐ethyl‐hexyloxy)‐1,4‐phenylenevinylene] (MEH‐PPV) on the top of optical fibers by using the soft lithographic technique of “liquid imprinting”. For this process master gratings (360 and 380 nm) for the feedback structure were fabricated via e‐beam lithography, transferred to an elastomeric stamp and used to imprint the grating into the highly luminescent conjugated polymer. Such second order gratings were photo‐pumped with a frequency doubled Nd:YAG laser, the laser emission (around 640 nm, depending on the used grating) was directly coupled into the waveguide and detected via a CCD spectrometer at the end of the fiber. The threshold of the laser devices was found to be in the range of 4.3 mJ/cm2 and exhibited a line width of approximately 2 nm. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In vitro activity of an essential oil against Leishmania donovani
Authors: Monzote L. , García M. , Montalvo A. M. , Scull R. , Miranda M. , Abreu J. 
Published: August 2007

AbstractThe in vitro antileishmanial effect of the essential oil from Chenopodium ambrosioides against Leishmania donovani was investigated. The product showed significant activity against promastigotes and amastigotes, with a 50% effective concentration of 4.45 and 5.1 µg/mL, respectively. The essential oil caused an irreversible inhibition of the growth of promastigotes after a treatment with 100 or 10 µg/mL for 1 or 24 h, respectively. The phagocytic activity of the macrophages was preserved at a concentration toxic to the parasite. The essential oil from C. ambrosioides may be a potential candidate drug to development a new agent to combat this parasitic disease. Copyright © 2007 John Wiley & Sons, Ltd.
Antibacterial activity of Chamomilla recutita oil extract against Helicobacter pylori
Authors: Shikov Alexander N. , Pozharitskaya Olga N. , Makarov Valery G. , Kvetnaya Asya S. 
Published: August 2007

AbstractThe antibacterial activity of an oil extract of Chamomilla recutita flowers against Helicobacter pylori (H. pylori) was evaluated by the agar dilution method using Colombia agar with 10% sheep blood, an inoculum of McFarland 0.5 and incubation in an anaerobic atmosphere at 37 °C for 3 days. The oil extract was prepared by olive oil extraction of Chamomilla recutita flowers using rotary pulsation. The MIC90 (minimal inhibitory concentration) and MIC50 were 125 mg/mL and 62.5 mg/mL, respectively. It was shown that the Chamomilla recutita oil extract inhibited the production of urease by H. pylori. In addition, it was found that the morphological and fermentative properties of H. pylori were affected by application of the Chamomilla recutita oil extract. Copyright © 2007 John Wiley & Sons, Ltd.
Antifibrotic effects of a herbal combination regimen on hepatic fibrotic rats
Authors: Lin Yun‐Lian , Hsu Yi‐Chao , Chiu Yung‐Tsung , Huang Yi‐Tsau 
Published: August 2007

AbstractLiver fibrosis has been characterized as chronic inflammatory processes involving multiple molecular pathogenetic pathways. This therapeutic study investigated whether a combination regimen of Salvia miltiorrhiza (S), Ligusticum chuanxiong (L) and Glycyrrhiza glabra (G) exerted in vivo antifibrotic effects on rats with hepatic fibrosis. Fibrosis was induced in rats by dimethylnitrosamine (DMN) administration for 4 weeks. Fibrotic rats were randomly assigned to one of the three groups: control, SLG (50 mg/kg) or silymarin (50 mg/kg), each given by gavage twice daily for 3 weeks starting 1 week after DMN injection. The results showed that fibrosis scores of livers from DMN‐treated rats with SLG (1.13 ± 0.13) were significantly reduced in comparison with DMN‐treated rats receiving vehicle (1.63 ± 0.18). Moreover, the hepatic collagen content of DMN rats was significantly reduced by either SLG or silymarin treatment. The double immunohistochemical staining results also showed that α‐SMA positive cells with NFκB nuclear translocation were decreased in the fibrotic livers by SLG and silymarin treatments. The mRNA expression levels of TGF‐β1, α‐SMA, collagen1α2, iNOS and ICAM‐1 genes were attenuated by SLG and silymarin treatment. The results showed that SLG exerted antifibrotic effects in rats with DMN‐induced hepatic fibrosis. Copyright © 2007 John Wiley & Sons, Ltd.
Anticonvulsant activity of Hypoxis hemerocallidea Fisch. & C. A. Mey. (Hypoxidaceae) corm (‘African potato’) aqueous extract in mice
Authors: Ojewole John A. O. 
Published: August 2007

AbstractExtracts of Hypoxis hemerocallidea Fisch. & C. A. Mey. (Hypoxidaceae) corm (popularly known as ‘African potato’) are extensively used in South African traditional medicines for the treatment, management and/or control of an array of human ailments, including childhood convulsions and epilepsy. This study examined the anticonvulsant activity of the plant's corm aqueous extract (APE, 50–800 mg/kg i.p.) against pentylenetetrazole (PTZ)‐, picrotoxin (PCT)‐ and bicuculline (BCL)‐induced seizures in mice. Phenobarbitone and diazepam were used as reference anticonvulsant drugs for comparison. Like the reference antiseizure drugs used, Hypoxis hemerocallidea corm aqueous extract (APE, 100–800 mg/kg i.p.) significantly delayed (p < 0.05–0.001) the onset of, and antagonized, pentylenetetrazole (PTZ)‐induced seizures. The plant's corm aqueous extract (APE, 100–800 mg/kg i.p.) also profoundly antagonized picrotoxin (PCT)‐induced seizures, but only weakly antagonized bicuculline (BCL)‐induced seizures. Although the data obtained in the present study do not provide conclusive evidence, it would appear that ‘African potato’ aqueous extract (APE) produces its antiseizure effect by enhancing GABAergic neurotransmission and/or action in the brain. The results of this laboratory animal study indicate that APE possesses anticonvulsant activity in the mammalian experimental model used and, therefore, tend to suggest that the herb may be used as a natural supplementary remedy in the management, control and/or treatment of childhood convulsions and epilepsy. In conclusion, the findings of this study indicate that Hypoxis hemerocallidea corm aqueous extract possesses anticonvulsant activity, and thus lend pharmacological credence to the suggested folkloric, anecdotal ethnomedical uses of the herb in the management of childhood convulsions and epilepsy in some rural communities of South Africa. Copyright © 2007 John Wiley & Sons, Ltd.
XPS investigations of ink‐jet printed paper
Authors: Lützenkirchen‐Hecht Dirk , Rohrmann Kay , Stöcker Thomas , Thiel Wolfgang 
Published: August 2007

AbstractDifferent ink‐jet printed paper materials were investigated using X‐ray photoelectron spectroscopy (XPS) yielding the elemental composition of the near‐surface region of the papers. We found significant differences with respect to the detected elements and their atomic concentrations in the different inks studied here. Two different groups of inks could be identified by means of a lower ratio of the O and C atomic concentrations and lower concentrations in specific trace elements like Mg, Na and Si. High‐resolution spectra of C 1s and O 1s core levels allowed a detailed determination of the chemical state of the respective elements. On the basis of a detailed deconvolution of these XPS signals, significant differences between all the investigated ink‐jet printed papers were found, thereby allowing their discrimination. The applicability of the measurements and, more generally, the XPS technique for forensic investigations of paper are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Randomization with a posteriori constraints: Description and properties
Authors: Gicquel Stéphanie , Marion‐Gallois Roland 
Published: August 2007

AbstractThe use of randomization for assigning patients to treatment groups in clinical trials is firmly acknowledged as providing the best quality results.Two standard methods are used in order to achieve well‐balanced groups with respect to prognostic factors (i.e. factors influencing the disease outcome): stratification and minimization. Stratification is recommended when the number of strata is not too high—otherwise, minimization is preferred. However, minimization may compromise blinding (since the search for balance is performed a priori) and, furthermore, use of the technique has been questioned by the European Agency for the Evaluation of Medicinal Products. We have developed a new procedure for adaptive randomization, which we have named ‘randomization with a posteriori constraints’. By using a search for balance a posteriori, this procedure ensures that patient groups are similar with respect to prognostic factors while being less vulnerable to selection bias. The aim of this work was to describe the new method and to compare it (using simulations) with stratification and minimization.In the case of trials with few
prognostic factors, the recourse to minimization or ‘randomization with a posteriori constraints’ does not appear to be useful. In such a context, stratification has suitable properties and its simplicity of implementation encourages its use. However, when the number of prognostic factors is higher, ‘randomization with a posteriori constraints’ is less predictable than minimization and the chance of imbalance is lower than for stratification. In conclusion, ‘randomization with a posteriori constraints’ with an adequate threshold seems to be a good compromise between minimization and stratification. Copyright © 2007 John Wiley & Sons, Ltd.
Sensitivity analysis of intention‐to‐treat estimates when withdrawals are related to unobserved compliance status
Authors: Salim Agus , Mackinnon Andrew , Griffiths Kathleen 
Published: August 2007

AbstractIn the presence of dropout, intent(ion)‐to‐treat analysis is usually carried out using methods that assume a missing‐at‐random (MAR) dropout mechanism. We investigate the potential bias caused by assuming MAR when the dropout is related to unobserved compliance status. A framework to assess the magnitude of bias in the context of pre‐ and post‐test design (PPD) with two treatment arms is presented. Scenarios with all‐or‐none and partial compliance level are investigated. Using two simulated data sets and actual data from an e‐mental health trial, we demonstrate the utility of sensitivity analyses to assess the bias magnitude and show that they are plausible options when some knowledge of compliance behaviour in the dropout exists. We recommend that our approach be used in conjunction with methods of analysis which assume MAR in estimating the ITT effect. Copyright © 2007 John Wiley & Sons, Ltd.
Experiences with building an intrusion‐tolerant group communication system
Authors: Ramasamy HariGovind V. , Pandey Prashant , Cukier Michel , Sanders William H. 
Published: August 2007

AbstractThere are many group communication systems (GCSs) that provide consistent group membership and reliable, ordered multicast properties in the presence of crash faults. However, relatively few GCS implementations are able to provide these properties in the presence of malicious faults resulting from intrusions. We describe the systematic transformation of a crash‐tolerant GCS, namely C‐Ensemble, into an intrusion‐tolerant GCS, the ITUA GCS. To perform the transformation, we devised intrusion‐tolerant versions of key group communication protocols. We then inserted implementations of the protocols into C‐Ensemble and made significant changes to the rest of the C‐Ensemble protocol stack to make the stack intrusion tolerant. We quantify the cost of providing intrusion‐tolerant group communication in two ways. First, we quantify the implementation effort by presenting a detailed analysis of the amount of change required to the original C‐Ensemble system. In doing so, we provide insight into the choice of building an intrusion‐tolerant GCS from scratch versus building one by leveraging a crash‐tolerant implementation. Second, we quantify the run‐time performance cost of tolerating intrusions by presenting results from an experimental evaluation of the main intrusion‐tolerant microprotocols. The results are analyzed to identify the parts that contribute the most overhead while providing intrusion tolerance during both normal operation and recovery from intrusions. Copyright © 2007 John Wiley & Sons, Ltd.
Toward a cross‐cultural theory of “exemplary organizations”: Evidence from Cuba
Authors: Cunha Miguel Pinae , Cunha Rita Campose , Rego Arménio 
Published: August 2007

AbstractManagement interest in “good companies to work for,” or “exemplary organizations,” has attracted the interest of researchers in the United States and Europe. We contribute to the literature on exemplary organizations by studying the representation of “exemplary organizations” in an unusual context, Cuba, and by inviting scholars to explore the cross‐cultural differences between what in different countries is viewed as an exemplary organization. Until now, studies on the best companies to work for have focused on companies operating in capitalistic economies. We aim to develop a better understanding of the representation of what a good place might be in an economic and ideological context that is in sharp contrast with the contexts in which this theme has been studied previously. © 2007 Wiley Periodicals, Inc.
Localized advantage in a global economy: The case of Bangalore
Authors: Nair Anil , Ahlstrom David , Filer Larry 
Published: August 2007

AbstractThis article examines how and why firms in Bangalore, a city in southern India, have achieved success in the global software industry. We use Porter's “diamond framework” to analyze information obtained from secondary sources and interviews with engineers, managers, and top executives from software firms and officials involved in Bangalore's development. While we found some aspects of the case conform to Porter's framework, many other elements tend to diverge from the model. Thus, the article contributes to the Porter's diamond model literature by extending its application to assessing the development of successful regions in knowledge‐based industries in developing economies. The discussion in the article would be of value to officials interested in creating such successful regions, as well as international business executives interested in the opportunities afforded by locating in these regions. © 2007 Wiley Periodicals, Inc.
New Doppler index for prediction of perinatal brain damage in growth‐restricted and hypoxic fetuses
Authors: Jugović D. , Tumbri J. , Medić M. , Jukić M. Kušan , Kurjak A. , Arbeille P. , Salihagić‐Kadić A. 
Published: August 2007

AbstractObjectiveTo evaluate the new vascular score, hypoxia index (HI), in the prediction of sonographically detected structural brain lesions in neonates within the first week after delivery of growth‐restricted fetuses.MethodsThis prospective study included 29 growth‐restricted fetuses delivered between 31 and 40 gestational weeks. Doppler umbilical artery (UA) and middle cerebral artery (MCA) resistance indices (RI) were recorded at 48‐h intervals for at least 2 weeks before delivery. The cerebroumbilical ratio (C/U ratio = MCA‐RI/UA‐RI) and the HI (the sum of the daily reductions in C/U ratio, i.e. percentage below the cut‐off value of 1, over the period of observation) were calculated. After delivery, neonatal outcome was evaluated according to obstetric parameters and ultrasound examinations of the brain. Doppler indices, C/U ratio and HI, as well as neonatal clinical and biochemical parameters, were tested as potential predictors of brain lesions using the C4.5 data‐mining algorithm.ResultsNeonatal brain lesions were detected in 13 growth‐restricted fetuses. Of all the parameters tested by the C4.5 data‐mining algorithm, only HI was identified as a predictor of neonatal brain lesions. HI also showed better correlation with neonatal biochemical parameters, such as umbilical venous partial pressure of oxygen and umbilical venous pH, compared with the C/U ratio.ConclusionsHI, which takes into account cumulative oxygen deficit, could significantly improve the prediction of a poor neurological outcome in pregnancies complicated by growth restriction and hypoxia. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.