bluuebunny/crossref_metadata_2025_split huggingface dataset:
Late human cytomegalovirus (HCMV) proteins inhibit differentiation of human neural precursor cells into astrocytes
Authors: Odeberg Jenny , Wolmer Nina , Falci Scott , Westgren Magnus , Sundtröm Erik , Seiger Åke , Söderberg‐Nauclér Cecilia 
Published: December 2006

AbstractHuman cytomegalovirus (HCMV) is the most common cause of congenital infections in developed countries, with an incidence varying between 0.5–2.2%. Such infection may be the consequence of either a primary infection or reactivation of a latent infection in the mother and the outcome may vary from asymptomatic to severe brain disorders. Moreover, infants that are asymptomatic at the time of birth may still develop neurologic sequelae at a later age. Our hypothesis is that infection of stem cells of the central nervous system by HCMV alters the proliferation, differentiation or migration of these cells, and thereby gives rise to the brain abnormalities observed. We show that infection of human neural precursor cells (NPCs) with the laboratory strain Towne or the clinical isolate TB40 of HCMV suppresses the differentiation of these cells into astrocytes even at an multiplicity of infection (MOI) as low as 0.1 (by 33% and 67%, respectively). This inhibition required active viral replication and the expression of late HCMV proteins. Infection as late as 24 hr after the onset of differentiation, but not after 72 hr, also prevented the maturation of infected cultures. Furthermore, in cultures infected with TB40 (at an MOI of 1), approximately 54% of the cells were apoptotic and cell proliferation was significantly attenuated. Clearly, HCMV can reduce the capacity of NPCs to differentiate into astrocytes and this effect may provide part of the explanation for the abnormalities in brain development associated with congenital HCMV infection. © 2006 Wiley‐Liss, Inc.
Job control and occupational health: the moderating role of national R&D activity
Authors: Daniels Kevin , Tregaskis Olga , Seaton Jonathan S. 
Published: December 2006

AbstractWorkers (n = 17 275) from 14 European Union (EU) member states provided data on job control, job dissatisfaction, perceived risk of occupational stress, and absence. For each state, level of research and development (R&D) activity was assessed. Associations between individual levels of control and occupational health were stronger where national R&D activity was higher. The moderation occurred for individuals' levels of control in relation to job dissatisfaction, perceived risk of occupational stress, and absence. The findings with job dissatisfaction and absence were replicated in a sample of workers from 10 Eastern European former Communist countries (n = 7926). Copyright © 2007 John Wiley & Sons, Ltd.
Comparative Raman spectroscopic analysis of orientation in fibers and regenerated films of Bombyx mori silk fibroin
Authors: Preghenella Michele , Pezzotti Giuseppe , Migliaresi Claudio 
Published: December 2006

AbstractThis study is focused on the Raman spectroscopic analysis of degummed silk fibroin (SF) fibers and regenerated Bombyx mori silk fibroin films: a correlation was found between some spectral features related to the methylene deformation modes and the molecular orientation of the samples.Polarized Raman spectra on SF fibers were used to obtain the orientation distribution function of carbonyl groups along the protein backbone. The variation of the intensity ratio of 1400/1450 cm−1 for the peaks attributed to the wagging and bending deformation modes of CH2 groups with respect to the angular orientation of the fiber was measured and quantitatively correlated with the orientation distribution function of the carbonyl groups.Unpolarized Raman spectra were measured for regenerated silk fibroin films and lyophilized solutions. The variation of the intensity ratio of 1415/1455 cm−1, which is related to the deformation modes of CH2 groups in SF regenerated materials, was qualitatively related to the microstructural orientation of the samples observed by scanning electron microscopy (SEM), and to the presence of Silk I phase as suggested by the analysis of samples obtained in different casting conditions and also by the measurements on mechanically deformed films.The results obtained showed the utility of the spectroscopic intensity ratio of 1400/1450 cm−1 for the rapid assessment of molecular orientation in silk fibers, which could be useful for quality and process control of regenerated silk‐based textiles. Moreover, the qualitative dependence of the intensity ratio of 1415/1455 cm−1 was found to be sensitive to both the microstructural orientation and Silk I content of regenerated silk fibroin films, suggesting a possible correlation of this Raman marker of the Silk I phase with the degree of molecular order brought about by this polymorph. Copyright © 2006 John Wiley & Sons, Ltd.
Gas chromatography‐mass spectrometry following pressurized hot water extraction and solid‐phase microextraction for quantification of eucalyptol, camphor, and borneol in Chrysanthemum flowers
Authors: Dong Ling , Wang Jiyao , Deng Chunhui , Shen Xizhong 
Published: December 2006

AbstractChrysanthemum flower is a common traditional Chinese medicine (TCM). In this work, pressurized hot water extraction (PHWE) followed by headspace solid‐phase microextraction (HS‐SPME) and GC‐MS was developed for the determination of three main active volatile compounds of eucalyptol, camphor, and borneol in Chrysanthemum flowers from four different growing areas in China by internal standard method. The parameters of PHWE and HS‐SPME were optimized. The method was also validated. The results showed that PHWE‐SPME‐GC‐MS is a simple, rapid, efficient, and solvent‐free technique for the quantitative determination of eucalyptol, camphor, and borneol in TCMs and is potentially useful for the TCM quality assessment.
Analysis of aromatic amines as N‐propoxycarbonyl derivatives by gas chromatography with nitrogen‐phosphorus selective detection
Authors: Kataoka Hiroyuki , Miyake Mina , Mitani Kurie 
Published: December 2006

AbstractA selective and sensitive method for the analysis of aromatic amines by GC was developed. Aromatic amines were converted to their N‐n‐propoxycarbonyl derivatives and measured by GC with nitrogen‐phosphorus selective detection (NPD) using an HP‐5 fused‐silica capillary column. The derivatives of the 20 aromatic amines provided excellent NPD responses, and were resolved both quantitatively and reproducibly within 15 min. The calibration curves for aromatic amines in the range 20–500 ng were linear and the detection limits at an S/N of 3 were ca. 19–139 pg injected. This method was applied successfully to combustion smoke and human urine samples, and analyzed without any interference from coexisting substances.
Simultaneous determination of catecholamines and amino acids by micellar electrokinetic chromatography with laser‐induced fluorescence detection
Authors: Zhou Lei , Wang Shumin , Tian Kan , Dong Yuming , Hu Zhide 
Published: December 2006

AbstractA selective and sensitive method was developed for separation and simultaneous determination of catecholamines and amino acids by MEKC with LIF. Interestingly enough, such work has been firstly performed on catecholamines derivatized with 4‐chloro‐7‐nitro‐2,1,3‐benzoxadiazole and the detailed derivatization mechanism was discussed. After derivatization at 60°C for 20 min, NBD‐labeled catecholamines and amino acids were separated in a buffer system containing 10 mM sodium tetraborate‐Na2HPO4, 20 mM SDS, and 10% v/v ACN at pH 9.75. SDS micelles were employed to improve the fluorescence intensity of catecholamine derivatives efficiently. Under optimum conditions, two catecholamines and 11 amino acids were separated in a short 13 min analysis time and the RSDs for migration time and peak area were less than 0.60 and 6.50%, respectively. The method was successfully applied for the quantification of catecholamines and amino acids in Portulaca oleracea L., human urine sample, and mixed injection sample.
Comparison of various extraction techniques for isolation and determination of isoflavonoids in plants
Authors: Bajer Tomáš , Adam Martin , Galla Lubomír , Ventura Karel 
Published: December 2006

AbstractIn the present paper, the following extraction techniques have been used for extracting isoflavonoids from the species Matricaria recutita, Rosmarinus officinalis, Foeniculum vulgare, and Agrimonia eupatoria L.: supercritical fluid extraction (SFE), pressurized fluid extraction, matrix solid phase dispersion, ultrasonic extraction in an ultrasonic bath (USE) and by means of an ultrasonic homogeniser (HOM), extraction by means of Soxhlet apparatus (SOX), and solid phase extraction. Experimental optimization of all techniques has been carried out using a soybean flour. Subsequent analyses of the extracts were carried out by liquid chromatography with UV detection. The maximum yields of daidzein and genistein were obtained by extraction with the SOX, USE, and HOM techniques. The maximum yields of apigenin and biochanin A from herb samples were obtained by SFE.
Sustained Epstein-Barr Virus Detection in Paediatric Liver Transplantation. Insights Into the Occurrence of Late PTLD
Authors: D'Antiga Lorenzo , Del Rizzo Monica , Mengoli Carlo , Cillo Umberto , Guariso Graziella , Zancan Lucia 
Published: December 2006

Abstract
Epstein-Barr virus (EBV) infection is the main cause of post-transplant lymphoproliferative disease (PTLD). Little is known on chronic carrier state and its relation with late PTLD. We aimed to study EBV infection in the long-term after paediatric liver transplantation (OLT). We conducted a retrospective review of 34 children monitored for a median of 5.8 years (range 1.5-17.7). 21 were IgG seronegative (group A) and 13 seropositive (group B) before OLT. Primary infection was the appearance of VCA-IgM or VCA-IgG or Real-Time Polymerase Chain Reaction (RT-PCR) in patients previously IgG seronegative; positive VCA-IgM or EA-IgG or RT-PCR lasting longer than 6 months was defined sustained viral detection (SVD). 18/21 patients of group A had a primary infection at a median time of 3 months after transplant (0.5-60). 14/18 of group A and 0/13 of group B had a SVD (P < 0.0001). Viral loads greater than 500 copies/10mononuclear cells occurred in 12/18 patients in group A and 0/13 patients in group B (P < 0.0001). The 3 patients who developed late PTLD (median time after OLT 47 months, range 15-121) were from group A, and presented with SVD before developing PTLD. In conclusion, EBV infection in seronegative patients at OLT is associated with greater viral loads and sustained viral detection. Late PTLD occurred only in naïve patients with markers of SVD. Three to 4 monthly long-term monitoring of EBV in pre-OLT naïve patients might help preventing the occurrence of late PTLD. Liver Transpl 13:343-348, 2007. 2006. © 2006 AASLD.
Comparison of Clinical Outcomes in Chronic Hepatitis B Liver Transplant Candidates with and Without Hepatocellular Carcinoma
Authors: Wong Stephen N. , Reddy Rajender K. , Keeffe Emmet B. , Han Steven-Huy , Gaglio Paul J. , Perrillo Robert P. , Tran Tram T. , Pruett Timothy L. , Lok Anna S.F. 
Published: December 2006

Abstract
Patients with hepatocellular carcinoma (HCC) receive a higher MELD score and may undergo liver transplantation (OLT) earlier compared to patients with cirrhosis, potentially decreasing waiting list mortality. However, post-OLT survival may be reduced by recurrence of HCC. We compared clinical outcomes between patients with HBV-cirrhosis and no HCC and patients with HBV-HCC. A total of 279 patients (HBV-cirrhosis = 183; HBV-HCC = 96) in the US HBV-OLT study were followed for a median of 30.2 months from listing. Patients with HCC were older, more likely to be Asian, and had less severe liver impairment than patients with HBV-cirrhosis. Despite a higher rate of OLT in patients with HCC (78.1% vs. 51.4%; P < 0.001), intention-to-treat (ITT) survival (73% vs. 78%) and survival without OLT (82% vs. 79%) at 5 years were similar for patients with and without HCC. Cox regression analysis identified higher albumin, lower MELD, no HCC at listing, and being transplanted to be associated with better ITT survival. Ninety-four patients with HCC (including 19 new HCC) and 75 with HBV-cirrhosis underwent OLT. Post-OLT survival (83% vs. 90%) and HBV recurrence (11% vs. 10%) at 3 years were similar, while disease (HBV and/or HCC) recurrence (19% vs. 10%; P = 0.043) was higher in patients with HBV-HCC vs. HBV-cirrhosis. Disease recurrence was the only independent predictor of post-OLT survival. In conclusion, despite more advanced liver disease and a lower rate of transplantation, ITT survival of patients listed for HBV-cirrhosis was comparable to those with HBV-HCC, possibly related to beneficial effects of antiviral therapy. Liver Transpl 13:334-342, 2007. © 2006 AASLD.
Structure analysis of Antonovsky's sense of coherence from an epidemiological mental health survey with a brief nine‐item sense of coherence scale
Authors: Klepp Olav Martin , Mastekaasa Arne , Sørensen Tom , Sandanger Inger , Kleiner Robert 
Published: December 2006

AbstractAntonovsky has proposed the sense of coherence (SOC) as a crucial factor that protects against symptoms of mental disease. A central issue in research on the SOC construct is whether this is most appropriately considered as one‐dimensional or three‐dimensional with comprehensibility (C), manageability (Ma) and meaningfulness (Me) as separate dimensions. In this paper we address this issue by means of confirmatory factor analysis of a shortened nine‐item version of Antonovsky's original 29‐ and 13‐items Sense of Coherence Scale (SOCS‐29), using epidemiological data from a mental health survey of adults in local communities (N = 1,062). In addition to analysing the internal structure of the SOC items, we examine the association between estimated factor scores and variables expected to be statistically related to SOC. Goodness‐of‐fit indices were very good for the three‐factor model but acceptable even for the one‐factor model. In the three‐factor model, however, the factors were found to be very highly or, with regard to Ma and C, even perfectly correlated. Moreover, the factor scores had very similar correlations with measures of psychological wellbeing, depression and anxiety and they are also very similarly related to age (and none of them are related to gender). We therefore conclude in favour of a one‐factor model. Copyright © 2006 John Wiley & Sons, Ltd.
1H and 13C chemical shifts for some tetrasubstituted 2,5‐diaryl di‐ and tetrahydrofuran derivatives
Authors: Martinet S. , Méou A. , Brun P. 
Published: December 2006

AbstractThe 1H and 13C NMR chemical shifts of four 2,5‐diaryltetrahydrofuran derivatives and their dihydro precursors were assigned completely with certainty using a concerted application of one‐ and two‐dimensional experiments (DEPT, gs‐COSY, gs‐HMQC and gs‐HMBC) Copyright © 2006 John Wiley & Sons, Ltd.
Tobacco smoke particulate matter chemistry by NMR
Authors: Barsanti Kelley C. , Luo Wentai , Isabelle Lorne M. , Pankow James F. , Peyton David H. 
Published: December 2006

AbstractThe submicron liquid droplets constituting the particulate matter of mainstream tobacco smoke (PMMTS) are viscous and of a composition that is complex and poorly understood. PMMTS is often ∼80% w/w ‘tar’ where ‘tar’ = total PMMTS− (nicotine + water). Many of the chemical agents in MTS responsible for smoking‐related cancers are found at least partially in the PMMTS portion of MTS. The properties of PMMTS vary with brand and with puffing patterns. The chemical forms and total levels of nicotine, the identities/levels of other compositionally dominant compounds, and the identities/levels of carcinogens are of interest. Most studies of the composition of PMMTS have involved extraction then chromatography. Such methods allow the determination of low‐level constituents, but alter the samples such that direct information regarding chemical conditions within the PMMTS cannot be obtained. Here, we utilize nuclear magnetic resonance spectroscopy (NMR) to examine native PMMTS in conventional cigarettes, including measurements of the brand‐dependent fraction of PMMTS nicotine that is in the free‐base form (increasing this fraction in inhaled tobacco smoke affects the rates of the processes governing nicotine deposition in the respiratory tract, and so has implications for smoking behavior and addiction). We also demonstrate the use of NMR for characterizing the composition of PMMTS (including the levels of selected cigarette additives) when the cosolvent DMSO‐d6 is added to improve spectral resolution. The native and solvent‐assisted results open the door to a range of future studies. Copyright © 2006 John Wiley & Sons, Ltd.
A 1H‐NMR thermometer suitable for cryoprobes
Authors: Findeisen M. , Brand T. , Berger S. 
Published: December 2006

AbstractMost established NMR thermometers rely on temperature‐dependent chemical shift differences measured from samples that are either neat or concentrated solutions (e.g. ethylene glycol, methanol). These are unsuitable for modern cryoprobes on account of strong radiation damping resulting from the high Q of the probe. Using perdeuterated methanol, we established a relationship between the chemical shift difference and temperature, and we show that this relationship is well fitted by a quadratic equation. The actual temperature within a sample tube in the probe was verified using a Pt‐100 resistor. Copyright © 2006 John Wiley & Sons, Ltd.
High‐performance parallel simulation of structure degradation using non‐local damage models
Authors: Germain Norbert , Besson Jacques , Feyel Frédéric , Gosselet Pierre 
Published: December 2006

AbstractSimulating damage and failure of metallic or composite structures often fails when using standard finite element discretizations and a Newton–Raphson solving procedure. The difficulties arise from an uncontrolled mesh dependency caused by damage localization, to structural instabilities and to an increase of computational costs. The first problem can be overcome by using non‐local damage constitutive equations together with a specific finite element model. The second problem can then be solved with an arc‐length method which manages instabilities and snap‐backs. They are caused by the loss of strength‐carrying capacity of the damaged material. Finally, the whole computational scheme is parallelized. The main contribution of this paper consists in bringing together the three numerical techniques: non‐local material model; piloting and parallel computations. The resulting numerical scheme allows to go beyond the overly simplistic cases often encountered in the literature. It allows robust industrial simulations with a high number of degrees of freedom, both in two and three dimensions, and deepened studies involving a large number of simulations. Copyright © 2006 John Wiley & Sons, Ltd.
Computation of Screening Phenonema in a Vertical Tumbling Cylinder
Authors: Alkhaldi Hashem , Eberhard Peter 
Published: December 2006

AbstractGranular materials are an integral part of our environment. Due to their wide variety of applications in industrial and technological processes, they have captured a great interest in the recent research, see [1] and [2]. The related studies are often based on numerical simulations and it is considered as challenging to investigate computational phenomena of dense granular systems. Particle screening is an essential technology in many industrial fields and important in granular studies. The particular problem of interest is the separation of round shape particles of different geometrical sizes using a rotating tumbling vertical cylinder. The concept of discrete element method (DEM) that considers the motion of each single particle individually is applied in this study. Particle‐to‐particle and particle‐to‐wall collisions will appear under the tumbling motion of the rotating structure. The normal and frictional forces between particles themselves and particles and surrounding walls of the structure are calculated according to the rules of a penalty method, which employs spring‐damper models for this purpose. As a result of collisions, the particles will dissipate kinetic energy due to the normal and frictional contact losses. Particle distribution and sifting rate of the separated particles have been studied taking into consideration different rotational speeds of the machine, various damping and frictional coefficients and different sizes of holes in the sifting plates at different levels of the structure. In an attempt to better understand the mechanism of the particle transport between the different layers of the sifting system, different computational studies have been performed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the use of Euler parameters in multibody dynamics
Authors: Betsch Peter 
Published: December 2006

AbstractEuler parameters (or unit quaternions) are known to be well‐suited for the singularity‐free description of finite rotations. Despite of this advantageous feature, the majority of rigid body integrators do not rely on Euler parameters. This observation might be closely related to the fact that the four Euler parameters are not independent. Thus the equations of motion in terms of Euler parameters inevitably assume the form of differential‐algebraic equations (DAEs). Since the early investigations dealing with Euler parameters in multibody dynamics, numerical methods for DAEs have improved significantly. Nowadays robust energy consistent integrators are available which exactly reproduce the property of workless constraint forces. The purpose of the present work is to revisit the use of Euler parameters in the light of state‐of‐the‐art integration schemes. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Some actual results of tire research in connection to the DFG Sonderforschungsbereich 181 (1986‐1996)
Authors: Böhm Friedrich , Duda Albert , Wille Ralf 
Published: December 2006

AbstractApplications of 2D and 3D tire models for car dynamics, landing of airplanes and off‐road vehicles are presented. For a big agricultural tire on pliable ground a multi‐point measurement device in the inner of the tire was developed, in order to verify computed rolling deformations. The measurement results in a soil channel at TU Munich also were compared with results of flat band testing. Theoretical investigations of tire behaviour were carried out on the basis of thin layered shell theory, together with Russian and Ukrainian scientists. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation of a deformable multibody system with hydraulics and control
Authors: Dibold Markus , Gerstmayr Johannes 
Published: December 2006

AbstractNumerous contributions have been made concerning multibody systems, hydraulic actuators or the design of feedback controllers. A system that combines these fields has been studied rarely. In the present work the systematic simulation of an entire machine, which consists of structural mechanical elements where single masses are transported, hydraulic actuation systems and a closed loop controller is studied. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)