bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling and simulation of ring deformation due to clamping
Authors: Sölter J.
Published: June 2009

The paper gives an overview of analytical models for calculating the out‐of‐roundness for rings clamped in a 3‐jaw‐chuck and addresses their limitations regarding their applicability in machining practice. Results from analytical models and Finite Element Analyses (FEA) of clamping rings with two different clamping sequences are compared and discussed. Analytical models are applied to predict elastic deformations and stresses for a ring clamped on the outer and inner surface with a 3‐jaw‐chuck. A combined approach of analytical models and FEA is used to calculate the out‐of‐roundness and the stress distribution of a ring clamped with a 3‐jaw‐chuck on the outside and with segment jaws on the inside. Especially the influence of the angular position between outer and inner clamping (0 °, 60 °) will be addressed. Additionally the expected shape changes will be qualitatively predicted from simulated elastic stresses. Finally, the simulation results are compared with measured out‐of‐roundness and residual stresses of machined rings.
Analysis of the forces in different regions during hobbing and their effect on distortion
Authors: Kohlhoff T.
Published: June 2009

By hobbing, distortion potential is induced into the workpiece, which leads to distortion of the gear teeth in the subsequent heat treatment process. To investigate the generation of distortion by hobbing precisely, the analysing methods have to be adapted to the process. To be able to choose adequate methods, preliminary investigations are accomplished to analyse the dimension and shape of the machining induced distortion. Since the hobbing process is divided into three regions with different process conditions, the influence of these differences on the distortion has to be considered. Therefore a variation of the facewidth is performed and the occurring forces are measured to analyse the process conditions. The results are used to derive suitable research and analysing methods.
Influence of clamping conditions on distortion during heating of bearing rings
Authors: Surm H. , Hoffmann F.
Published: June 2009

In experimental examinations, the change in roundness deviations of bearing rings due to quench hardening was exclusively determined by the used clamping technique during turning, which led to a characteristic manufacturing residual stress state. In the present paper, the influence of manufacturing residuals stresses on distortion was studied by means of finite element analysis. Therefore, a typical residual stress distribution in a bearing ring after machining was generated in a first simulation procedure. The calculated residual stress profiles were in good agreement with XRD‐measurements. In a second step, a homogeneous heating up to transformation temperature Ac1was simulated. Stress relief can be attributed to local plastic deformation if the local equivalent stress approached the temperature dependent yield strength. Rearrangement of stresses in the complete ring can be correlated to temperature dependent change in roundness deviation. From the comparison of the simulated roundness deviation with experimental results, it could be concluded that plastic deformation by stress relief during heating could be a significant distortion mechanism regarding the roundness deviation of bearing rings.
In‐process measurement system based on laser triangulation during heat treatment
Authors: Gafsi H. , Goch G.
Published: June 2009

This paper presents the calibration and the use of a laser triangulation system for non‐contact measurements of workpiece geometry changes during heat treatment. The system was developed within the scope of the Collaborative Research Centre SFB570 of the Deutsche Forschungsgemeinschaft to provide geometrical information obtained in hot environments (temperatures up to 900 °C) for the verification of heat treatment simulations. Due to its in‐process‐measurement capability, this system also enables the closed‐loop control of distortion compensation. It will be applied in a furnace specially designed for heating steel rings symmetrically or asymmetrically.

The developed calibration routine, which includes the application of gauge rings with different diameters, is described and the obtained uncertainties are discussed. Measurement results of an austenitic cylindrical ring are compared with reference dilatometry data to validate the calibration routine.
The heat treatment of steel – a mathematical control problem
Authors: Hömberg D. , Kern D.
Published: June 2009

The goal of this paper is to show how the heat treatment of steel can be modelled in terms of a mathematical optimal control problem. The approach is applied to laser surface hardening and the cooling of a steel slab including mechanical effects. Finally, it is shown how the results can be utilized in industrial practice by a coupling with machine‐based control.
Similarities and differences in heat treatment simulation of aluminium alloys and steels
Authors: Kessler O. , Reich M.
Published: June 2009

Aluminium alloys are nowadays applied in light weight constructions of many areas, e.g. transportation. Several manufacturing technologies are used in production chains of aluminium components. For improvements in strength heat treatments are carried out with aluminium alloys (precipitation hardening) as well as with steels (martensitic hardening). Besides the intended microstructures and properties, dimension and shape changes as well as residual stresses of the components are heat treatment results. Simulation tools based on the finite element method help to predict heat treatment results without extensive tests. Among other inputs one necessary pre‐requisite is a detailed database for the material. This database must contain the fundamental material parameters like heat conductivity, specific heat capacity, density, thermal expansion coefficient, modulus of elasticity, Poisson´s ratio and strain hardening, all of them depending on phases and temperature. Further, models for phase transformations and precipitation processes must be implemented. For steels heat treatment simulations of complex components are already possible. Some heat treatment parameters and material parameters of steels and aluminium alloys differ significantly. Aluminium alloys usually exhibit lower solution annealing temperatures, higher cooling rates, higher heat conductivity, higher thermal expansion coefficient, lower modulus of elasticity and lower strength. Further, the material database is partially missing for aluminium alloys, especially precipitation models. Exemplarily heat treatment simulations focused on the material parameters of aluminium alloys will be presented and similarities as well as differences compared to steels will be discussed.
Simulation of the distortion manipulation of gear wheel teeth by thermal pre‐stressing
Authors: Pretorius T. , Vollertsen F.
Published: June 2009

An additional process step in the production process chain of steel components, the thermal induced pre‐stressing, has been developed. This new process step enables the manipulation of the distortion potential of the components before it is released in the hardening process at the end of the process chain. In order to predict the final distortion of the component in dependence on the process parameters of the thermal pre‐stressing a simulation model has been developed, which also includes the final heat treatment (hardening process). The model accounts for the stress and deformation due to the generation of thermal strain as well as those due to phase transformations. A first implementation was done using the geometry of an idealized gear wheel tooth (finger sample). After optimization, with special focus on the calculation time, the application for realistic gear wheel teeth has been implemented.
Deep brain stimulation and cognitive functions in Parkinson's disease: A three‐year controlled study
Authors: Zangaglia Roberta , Pacchetti Claudio , Pasotti Chiara , Mancini Francesca , Servello Domenico , Sinforiani Elena , Cristina Silvano , Sassi Marco , Nappi Giuseppe
Published: June 2009

There is debate over the cognitive and behavioral effects of deep brain stimulation (DBS) of the subthalamic nucleus (STN) in advanced Parkinson's disease (PD). To evaluate these effects, we performed a prospective, naturalistic controlled, 3‐year follow‐up study. A total of 65 PD patients were enrolled, of whom 32 underwent STN‐DBS (PD‐DBS) and 33, even though eligible for this treatment, declined surgery and chose other therapeutic procedures (PD‐control). Motor and neuropsychological functions were assessed in all the subjects at baseline (T0) and 36 months (T36). The PD‐DBS patients were also evaluated at 1, 6, 12, and 24 months after surgery (T1, T6, T12, and T24). At T1, compared with T0, the PD‐DBS patients recorded worse logical executive function task and verbal fluency (FAS) scores, whereas their performance of memory tasks remained stable. At T12, their cognitive profile had returned within the pre‐DBS range, thereafter remaining stable until T36. FAS scores at T36 were significantly worse in the PD‐DBS compared with the PD‐control patients. This is the first long‐term naturalistic controlled study of cognitive functions in PD patients submitted to STN‐DBS. Our results confirm previous reports of a worsening of verbal fluency after DBS, but show that STN‐DBS seems to be relatively safe from a cognitive standpoint, as the short‐term worsening of frontal‐executive functions was found to be transient. © 2009 Movement Disorder Society
Essential tremor in Parkinson's disease kindreds from a population of similar genetic background
Authors: Spanaki Cleanthe , Plaitakis Andreas
Published: June 2009

To investigate the possible association between essential tremor (ET) and Parkinson's disease (PD) we conducted a prospective clinical and epidemiological study in a population of similar genetic background. The first‐degree relatives of 303 PD probands and 249 controls from Crete were evaluated for the presence of ET. In addition, the possible co‐occurrence of ET and PD in the same family or in the same individual was investigated. Results showed that ET was present in the relatives of PD patients more often than in those of controls (OR:3.64, P < 0.001). The risk was even greater (OR: 4.48) when the affected proband had tremor‐dominant or mixed PD. Female relatives and siblings of PD patients were more likely to have ET than male relatives and parents of PD patients (OR: 4.36 v/s 2.89 and 4.49 v/s 2.74, respectively). Twelve subjects had both ET and PD phenotypes. While this may have occurred by chance, a number of families were identified in which ET and PD were coinherited through the same parental line. Hence, in certain families ET and PD are genetically related probably sharing common hereditary predisposition. © 2009 Movement Disorder Society
Is impact of fatigue an independent factor associated with physical activity in patients with idiopathic Parkinson's disease?
Authors: Elbers Roy , van Wegen Erwin E.H. , Rochester Lynn , Hetherington Victoria , Nieuwboer Alice , Willems Anne‐Marie , Jones Diana , Kwakkel Gert
Published: June 2009

To investigate the longitudinal association between fatigue and physical activity in Parkinson's disease (PD) and determine whether this association is distorted by potential confounders. Data from baseline, 3, 6, and 12 week assessments in a single blind randomized clinical trial with cross‐over design were used (N = 153). The Multidimensional Fatigue Inventory (MFI) was used to assess fatigue and an activity monitor to measure amount of physical activity (defined as % dynamic activity during each monitoring session). Time‐independent and time‐dependent factors were investigated for their possible univariate association with dynamic activity. Random coefficient analysis was applied. Candidate confounders were successively added to the longitudinal association model to determine if the association between dynamic activity and fatigue was distorted. A proportional change beyond 15% was considered to be significant. Fatigue was significantly associated with physical activity (β = −0.099, SE = 0.032, P = 0.002). This association was not significantly distorted by type of intervention, age, gender, social support, disease duration, disease severity, motor impairment, cognition, anxiety, or medication intake. Depression caused proportional change of 22.2% in the regression coefficient of MFI. After controlling for depression, a significant association between MFI and dynamic activity remained (β = −0.121, SE = 0.036, P = 0.000). The association found between fatigue and dynamic activity suggests that patients who experience higher levels of fatigue are less physically active. However, the total explained variance of dynamic activity by fatigue alone was small, suggesting that fatigue is only a minor factor in the complex of behavioral aspects that affect the amount of physical activity in patients with PD. © 2009 Movement Disorder Society
‘Extra information a bit further down the line’: Rheumatoid arthritis patients' perceptions of developing educational material about the cardiovascular disease risk
Authors: John Holly , Hale Elizabeth D. , Treharne Gareth J. , Carroll Douglas , Kitas George D.
Published: June 2009

Objective: There are no patient education programmes addressing the increased risk of cardiovascular disease (CVD) associated with rheumatoid arthritis (RA). This is the second in a pair of studies exploring stakeholder perceptions of developing such educational material. Healthcare professionals' perceptions were explored in the first study; here, we explore the perceptions of people with RA.

Methods: Semi‐structured interviews were held individually with 18 people with RA, purposively sampled to include participants with no co‐morbid history of CVD, those with CVD risk factors and those who had experienced a CVD event. The interview transcripts were analysed using interpretative phenomenological analysis.

Results: Four superordinate themes were identified: experiences of living with RA; reactions to learning about co‐morbid CVD; implementing lifestyle changes; and expectations of education. Participants found being diagnosed with RA a devastating experience and were mostly unaware of their increased risk of CVD co‐morbidity. They explained how information about CVD would be overwhelming and irrelevant at diagnosis, but they would have coped with ‘extra information a bit further down the line’.

Conclusion: There is a need to develop educational material or programmes. Their design must consider factors which facilitate lifestyle change, such as motivation or receiving personalized advice, and factors that inhibit change, such as depression or fatalism. Emphasizing the positive effects that some CVD lifestyle changes may have on RA symptom control may be particularly persuasive. Group education would be a popular format. These findings can be directly translated into clinical practice. Copyright © 2009 John Wiley & Sons, Ltd.
Changes in hemiplegic grasp following distributed repetitive intervention: a case series
Authors: Conti Gerry E. , Schepens Stacey L.
Published: June 2009

The purpose of this pilot study was to investigate the efficacy of a distributed model of repetitive and focused intervention on grasp force, and clinical and functional hand measures in persons with chronic hemiplegia and limited hand recovery from self‐reported stroke.

A case series design was used. Focused repetitive unilateral and bilateral interventions were provided in a distributed manner (three times a week for 6 weeks) to three persons with upper limb hemiplegia of more than 1 year. Data from instrumented grasp force, and clinical and functional measures were obtained at weeks 0, 3, 6 and 9.

Each participant improved in at least one measure of grasp force, as well as in clinical skill and function. All participants improved in the quality of handwriting. Improved outcomes remained above baseline levels following 3 weeks of non‐intervention. The findings are compatible with current evidence of adaptive cortical plasticity following increased repetition. The findings show that, for these three persons, distributed repetitive practice was sufficient to effect change.

Localization by cerebral area affected is not possible, nor is it possible to parse the effectiveness of any component of the intervention.

A larger group study is warranted to determine whether similar results may be found for other persons with chronic hemiplegia. Future studies should incorporate kinematic handwriting analysis and a greater range of functional tasks. Copyright © 2009 John Wiley & Sons, Ltd.
Behind closed doors: systematic analysis of breast cancer consultation communication and predictors of satisfaction with communication
Authors: Hack Thomas F. , Pickles Tom , Ruether J. Dean , Weir Lorna , Bultz Barry D. , Degner Lesley F.
Published: June 2009

Objective: The purpose of this investigation was to explicate the content of primary adjuvant treatment consultations in breast oncology and examine the predictive relationships between patient and oncologist consultation factors and patient satisfaction with communication.

Methods: The recorded consultations of 172 newly diagnosed breast cancer patients from four Canadian cancer centers were randomly drawn from a larger subset of 481 recordings and examined by three coders using the Medical Interaction Process System (MIPS); a system that categorizes the content and mode of each distinct utterance. The MIPS findings, independent observer ratings of patient and oncologist affective behavior, and derived consultation ratios of patient centeredness, patient directedness, and psychosocial focus, were used to predict patient satisfaction with communication post‐consultation and at 12‐weeks post‐consultation.

Results: Biomedical content categories were predominant in the consultations, accounting for 88% of all utterances, followed by administrative (6%) and psychosocial (6%) utterances. Post‐consultation satisfaction with communication was significantly higher for older patients, those with smaller primary tumors and those with longer consultations. Smaller tumor, lack of patient assertiveness during the treatment consultation and having the consultation with a radiation rather than medical oncologist were significantly predictive of greater satisfaction at 12‐weeks post‐consultation.

Conclusions: Adjuvant treatment consultations are characterized by a high degree of information‐giving by the physician, a predominance of biomedical discussion and relatively minimal time addressing patients' psychosocial concerns. Controlled trials are needed to further identify and address the contextual features of these consultations that enhance patient satisfaction. Copyright © 2009 John Wiley & Sons, Ltd.
The impact of different definitions and reference groups on the prevalence of cognitive impairment: a study in postmenopausal breast cancer patients before the start of adjuvant systemic therapy
Authors: Schilder Christina M. , Seynaeve Caroline , Linn Sabine C. , Boogerd Willem , Gundy Chad M. , Beex Louk V. , van Dam Frits S. , Schagen Sanne B.
Published: June 2009

Objective: Several prospective studies into the effects of adjuvant systemic therapy on cognitive functioning suggest that a proportion of breast cancer patients show cognitive deficits already before the start of systemic therapy. Owing to, among others, methodological inconsistency, studies report different rates of this pre‐treatment cognitive impairment. We examined the impact of four different criteria of cognitive impairment and two types of reference groups (a study‐specific healthy reference group versus published normative data) on the prevalence of cognitive impairment.

Methods: Two hundred and five postmenopausal breast cancer patients underwent a battery of neuropsychological tests before the start of endocrine therapy, 124 healthy subjects underwent the same tests. Proportions of cognitive impaired patients were calculated for each of four criteria for cognitive impairment, using (1) study‐specific healthy controls and (2) published norms of healthy controls as reference groups.

Results: The prevalence of cognitive impairment varied greatly with the strictness of the criterion, as expected, but also was dependent on the reference group used. Cognitive impairment, relative to published norms, ranged from 1% for the strictest to 36.6% for the less strict criterion, cognitive impairment relative to study‐specific healthy controls, ranged from 13.7 to 45.4% for the same criteria.

Conclusion: This study highlights contrasting proportions of cognitive impairment by using different criteria for cognitive impairment and different reference groups. (Dis)advantages of the methods using a criterion for cognitive impairment, and of the use of published norms versus a study‐specific reference group are discussed. Copyright © 2009 John Wiley & Sons, Ltd.
InAlN‐barrier HFETs with GaN and InGaN channels
Authors: Liberis J. , Matulionienė I. , Matulionis A. , Šermukšnis E. , Xie J. , Leach J. H. , Morkoç H.
Published: June 2009

Advantages and drawbacks of InN‐containing GaN‐based heterostructure field‐effect transistors (HFETs) are reviewed. The main attention is paid to fundamental processes and experimental observations associated with hot‐electron transport in two‐dimensional electron gas (2DEG) channels subjected to high electric fields. Complementary information is obtained from fluctuations. When interface roughness and alloy scattering are minimized, an important transport limitation originates from additional scattering of hot electrons by non‐equilibrium longitudinal optical (LO) phonons (hot phonons) governed by the hot‐phonon temperature and the hot‐phonon decay into acoustic phonons. The ultrafast decay is observed for high supplied power where the hot‐phonon lifetime of ∼60 fs is found. The optimal 2DEG density for the fastest decay of hot phonons is estimated and associated with LO‐phonon–plasmon resonance. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
SiC avalanche photodiodes and photomultipliers for ultraviolet and solar‐blind light detection
Authors: Vert Alexey , Soloviev Stanislav , Sandvik Peter
Published: June 2009

Silicon carbide (SiC) is known for its large bandgap and suitability to make direct conversion ultraviolet photo‐detectors. These devices show appreciable quantum efficiencies in the 240–350 nm wavelength range in combination with low dark currents. This paper presents recent study results of 4H‐SiC avalanche photodiodes and solid‐state photomultiplier arrays. The material quality is an issue that has to be addressed. It has been found that a large number of defects in the device structure could substantially affect the single‐photon avalanche diodes yield, while regular photodiodes yield is more immune to the presence of defects. Some single‐photon avalanche photodiodes have demonstrated low dark count rates in the range of several kHz and single photon detection efficiency of more than 10% at 266 nm in the solar‐blind wavelengths range. A novel SiC‐based 12‐pixel photomultiplier array was demonstrated for the first time. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Receptor binding activities of Chlorella on cysteinyl leukotriene CysLT, glutamate AMPA, ion channels, purinergic P2Y, tachykinin NK2receptors and adenosine transporter
Authors: Cheng Fong‐Chi , Feng Jin‐Jye , Chen Kuo‐Hsin , Imanishi Hideyo , Fujishima Masaki , Takekoshi Hideo , Naoki Yo , Shimoda Minoru
Published: June 2009

A Chlorella powder was tested in a total of 129in vitroreceptor binding assay systems. The results showed a potent inhibition of this powder on cysteinyl leukotriene CysLT2, and glutamate AMPA in a dose‐concentration manner with IC50mean ± SEM values of 20 ± 4.5 µg/mL and 44 ± 14 µg/mL, respectively. Other moderate and weak activities reflected in competitive binding experiments were seen versus adenosine transporter; calcium channel L‐type, benzothiazepine; gabapentin; kainate, NMDA‐glycine; inositol trisphosphate IP3; cysteinyl CysLT1, LTB4; purinergic P2Y; tachykinin NK2; serotonin 5‐HT2Band prostanoid, thromboxane A2. Together, the results suggest that the various inhibitory effects of Chlorella powder in these receptor binding assays could reflect its actions in modulating Ca2+‐dependent signal related targets and might be relevant to the mechanisms of its biological effects. These results reveal important potential biochemical activities that might be exploited for the prevention or treatment of several pathologies. From these results, the possible therapeutic usage of the product is discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Evaluation of the metabolism of propranolol by linear ion trap technology in mouse, rat, dog, monkey, and human cryopreserved hepatocytes
Authors: Baughman Todd M. , Talarico Christine L. , Soglia John R.
Published: June 2009

Propranolol is a widely used quality control and validation compound for liver microsome and hepatocyte metabolism studies. A multitude of literature reports describing the identification of propranolol metabolites exists today. However, no literature reports currently exist showing hepatocyte metabolism across the five species commonly used during pre‐clinical drug discovery, namely mouse, rat, dog, monkey, and human. Herein, we present full metabolic profiles of propranolol in mouse, rat, dog, monkey and human hepatocytes. As expected, extensive phase I and phase II metabolism was observed across all five species and species‐specific metabolites were detected in monkey and dog hepatocytes. Of particular interest was the detection of anN‐hydroxylamine glucuronide metabolite in monkey and dog hepatocytes. Copyright © 2009 John Wiley & Sons, Ltd.
Rapid mixing of Gibbs sampling on graphs that are sparse on average
Authors: Mossel Elchanan , Sly Allan
Published: June 2009

Gibbs sampling also known as Glauber dynamics is a popular technique for sampling high dimensional distributions defined on graphs. Of special interest is the behavior of Gibbs sampling on the Erdős‐Rényi random graphG(n,d/n), where each edge is chosen independently with probabilityd/nanddis fixed. While the average degree inG(n,d/n) isd(1 ‐o(1)), it contains many nodes of degree of order logn/log logn.

The existence of nodes of almost logarithmic degrees implies that for many natural distributions defined onG(n,p) such as uniform coloring (with a constant number of colors) or the Ising model at any fixed inverse temperature β, the mixing time of Gibbs sampling is at leastn1+Ω(1/log logn). Recall that the Ising model with inverse temperature β defined on a graphG= (V,E) is the distribution over {±}Vgiven by$ P(\sigma) = {1 \over Z} \exp (\beta \Sigma_{(v,u)\varepsilon E}\ \sigma(v)\sigma(u)) $. High degree nodes pose a technical challenge in proving polynomial time mixing of the dynamics for many models including the Ising model and coloring. Almost all known sufficient conditions in terms of β or number of colors needed for rapid mixing of Gibbs samplers are stated in terms of the maximum degree of the underlying graph.

In this work, we show that for everyd< ∞ and the Ising model defined onG(n,d/n), there exists a βd> 0, such that for all β < βdwith probability going to 1 asn→∞, the mixing time of the dynamics onG(n,d/n) is polynomial inn. Our results are the first polynomial time mixing results proven for a natural model onG(n,d/n) ford> 1 where the parameters of the model do not depend onn. They also provide a rare example where one can prove a polynomial time mixing of Gibbs sampler in a situation where the actual mixing time is slower thannpolylog(n). Our proof exploits in novel ways the local tree like structure of Erdős‐Rényi random graphs, comparison and block dynamics arguments and a recent result of Weitz.

Our results extend to much more general families of graphs which are sparse in some average sense and to much more general interactions. In particular, they apply to any graph for which every vertexvof the graph has a neighborhoodN(v) of radiusO(logn) in which the induced sub‐graph is a tree union at mostO(logn) edges and where for each simple path inN(v) the sum of the vertex degrees along the path isO(logn). Moreover, our result apply also in the case of arbitrary external fields and provide the first FPRAS for sampling the Ising distribution in this case. We finally present a non Markov Chain algorithm for sampling the distribution which is effective for a wider range of parameters. In particular, forG(n,d/n) it applies for all external fields and β < βd, wheredtanh(βd) = 1 is the critical point for decay of correlation for the Ising model onG(n,d/n). © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2009
Hydrogen‐Bonded Molecular Networks of Melamine and Cyanuric Acid on Thin Films of NaCl on Au(111)
Authors: Bombis Christian , Kalashnyk Nataliya , Xu Wei , Lægsgaard Erik , Besenbacher Flemming , Linderoth Trolle R.
Published: June 2009

Self‐assembly of organized molecular structures on insulators is technologically very relevant, but in general rather challenging to achieve due to the comparatively weak molecule–substrate interactions. Here the self‐assembly of a bimolecular hydrogen‐bonded network formed by melamine (M) and cyanuric acid (CA) on ultrathin NaCl films grown on a Au(111) surface is reported. Using scanning tunneling microscopy under ultrahigh‐vacuum conditions it is demonstrated that it is possible to exploit strong intermolecular forces in the M–CA system, resulting from complementary triple hydrogen bonds, to grow 2D bimolecular networks on an ultrathin NaCl film that are stable at a relatively high temperature of ≈160 K and at a coverage below saturation of the first molecular monolayer. These hydrogen‐bonded structures on NaCl are identical to the self‐assembled structures observed for the M–CA system on Au(111), which indicates that the molecular self‐assembly is not significantly affected by the isolating NaCl substrate.
Non‐centrosymmetric rubidium rare‐earth nitrates Rb2RE(NO3)5 · 4H2O: Crystal growth and optical properties
Authors: Bohatý Ladislav , Held Peter , Becker Petra
Published: June 2009

Large single crystals of optical quality of the isomorphic, non‐centrosymmetric, monoclinic (space group Cc) compounds Rb2LA(NO3)5 · 4H2O and Rb2Ce(NO3)5 · 4H2O were grown. The determination of precise refractive indices and their dispersion in the wavelength region 0.365–1.083 μm allowed a detailed analysis of phase matching conditions for nonlinear optical second harmonic generation. Type I phase matching conditions can be realized in both crystals for a wide frequency range. Our X‐ray structure determination of Rb2Nd(NO3)5 · 4H2O and Rb2Pr(NO3)5 · 4H2O shows that both compounds are isomorphic to the lanthanum and cerium compounds.
Exercise Induced Chronic Compartment Syndrome of the First Dorsal Interosseous Compartment of the Hand: A Case Report
Authors: Chopra Rajat , Hayton Mike , Dunbar P. J. A.
Published: June 2009

Exercise-induced chronic compartment syndrome in the first dorsal compartment is an uncommon entity and relatively rare condition which is not very well understood. It is a usually activity-related condition and is associated with decreased function of muscle with intracompartmental swelling. We present a case with proven exercise-induced raised compartment pressure that responded well to surgical fasciotomy.
Perceived Corporate Reputation and Consumer Satisfaction – an Experimental Exploration of Causal Relationships
Authors: Helm Sabrina , Garnefeld Ina , Tolsdorf Julia
Published: June 2009

Corporate reputation is increasingly recognised as an important intangible asset of the firm. Therefore, investigating its causes and consequences is of interest to practice and research alike. While some authors argue that consumer satisfaction is a cause of reputation, others hold the contrary view and claim that reputation determines satisfaction. This controversy in the literature is the starting point for the present paper in which the causality of the relationship between corporate reputation and consumer satisfaction is investigated. By conducting two experiments, we show a significant effect of consumer satisfaction onto corporate reputation as perceived by consumers. However, no significant impact of reputation onto satisfaction could be detected. These findings lead to implications for the marketing of new products and firms’ reputation management.
Effects and mechanisms of proton pump inhibitors as a novel chemosensitizer on human gastric adenocarcinoma (SGC7901) cells
Authors: Chen Min , Zou Xiaoping , Luo Hesheng , Cao Jun , Zhang Xiaoqi , Zhang Bin , Liu Wenjia
Published: June 2009

Upregulation of proton extrusion is critical for tumor cell survival in an ischemic microenvironment with a lower extracellular pH (pHe). Lower pHe and higher intracellular pH (pHi) benefit cancer cells for invasion and growth. Vacuolar H+‐ATPases (V‐H+‐ATPases) play a critical role in regulating the transmembrane pH gradient. Proton Pump Inhibitors (PPI), mainly treating acid‐related diseases, could inhibit the expression of V‐H+‐ATPases. We have investigated whether PPI decreases the pHi of the human gastric adenocarcinoma cell line, SGC7901, by inhibiting V‐H+‐ATPases so as to enhance the cytotoxicity of anti‐tumor drugs. We have assessed the optimal treatment time, pretreatment dosage of PPI and the possible mechanism of action. PPI exceeding 10 μg/ml inhibited protein expression of V‐H+‐ATPases in a dose‐dependent manner, decreased the pHi value and reversed the transmembrane pH gradient, whereas PPI at final concentration of 1 μg/ml could not. Changes of the pH gradient were positively correlated with PPI concentration. The inhibitory effects of PPI on V‐H+‐ATPases primarily occurs from 12 h to 24 h after PPI pretreatment (P < 0.05). The pHi value of SGC7901 was lowest 24 h after PPI pretreatment (P < 0.05). Administration of anti‐tumor drugs 24 h after PPI pretreatment produced the most cytotoxic effects on SGC7901 (P < 0.05) and significantly improved the early and total apoptosis rates (P < 0.01). PPI exceeding 20 μg/ml also significantly reduced the ADR‐releasing index, thereby enhancing the intracellular ADR concentration (P < 0.01). Therefore, PPI could enhance the cytotoxic effects of anti‐tumor drugs on the SGC7901 cells.
The nociceptive withdrawal reflex: Normative values of thresholds and reflex receptive fields
Authors: Neziri Alban Y. , Andersen Ole K. , Petersen‐Felix Steen , Radanov Bogdan , Dickenson Anthony H. , Scaramozzino Pasquale , Arendt‐Nielsen Lars , Curatolo Michele
Published: June 2009

Assessments of spinal nociceptive withdrawal reflexes can be used in human research both to evaluate the effect of analgesics and explore pain mechanisms related to sensitization. Before the reflex can be used as a clinical tool, normative values need to be determined in large scale studies. The aim of this study was to determine the reference values of spinal nociceptive reflexes and subjective pain thresholds (to single and repeated stimulation), and of the area of the reflex receptive fields (RRF) in 300 pain‐free volunteers. The influences of gender, age, height, weight, body‐mass index (BMI), body side of testing, depression, anxiety, catastrophizing and parameters of Short‐Form 36 (SF‐36) were analyzed by multiple regressions. The 95% confidence intervals were determined for all the tests as normative values. Age had a statistically and quantitatively significant impact on the subjective pain threshold to single stimuli. The reflex threshold to single stimulus was lower on the dominant compared to the non‐dominant side. Depression had a negative impact on the subjective pain threshold to single stimuli. All the other analyses either did not reveal statistical significance or displayed quantitatively insignificant correlations. In conclusion, normative values of parameters related to the spinal nociceptive reflex were determined. This allows their clinical application for assessing central hyperexcitability in individual patients. The parameters investigated explore different aspects of sensitization processes that are largely independent of demographic characteristics, cognitive and affective factors.
Locally constant functors
Authors: CISINSKI DENIS–CHARLES
Published: June 2009

We study locally constant coefficients. We first study the theory of homotopy Kan extensions with locally constant coefficients in model categories, and explain how it characterizes the homotopy theory of small categories. We explain how to interpret this in terms of left Bousfield localization of categories of diagrams with values in a combinatorial model category. Finally, we explain how the theory of homotopy Kan extensions in derivators can be used to understand locally constant functors.
Participants' Experiences of Mindfulness-Based Cognitive Therapy: “It Changed Me in Just about Every Way Possible”
Authors: Allen Mark , Bromley Andrew , Kuyken Willem , Sonnenberg Stefanie J.
Published: June 2009

Background: Mindfulness-Based Cognitive Therapy (MBCT) is a promising approach to help people who suffer recurrent depression prevent depressive relapse. However, little is known about how MBCT works. Moreover, participants' subjective experiences of MBCT as a relapse prevention treatment remain largely unstudied. Aim: This study examines participants' representations of their experience of MBCT and its value as a relapse-prevention program for recurrent depression. Method: Twenty people who had participated in MBCT classes for recurrent depression within a primary care setting were interviewed 12 months after treatment. The focus of the interview was on participants' reflections on what they found helpful, meaningful and difficult about MBCT as a relapse prevention program. Thematic analysis was used to identify the key patterns and elements in participants' accounts. Results and conclusions: Four overarching themes were extracted: control, acceptance, relationships and struggle. The theoretical, clinical and research implications are discussed.
The phylogeny of invertebrates and the evolution of myelin
Authors: Roots Betty I.
Published: June 2009

Current concepts of invertebrate phylogeny are reviewed. Annelida and Arthropoda, previously regarded as closely related, are now placed in separate clades. Myelin, a sheath of multiple layers of membranes around nerve axons, is found in members of the Annelida, Arthropoda and Chordata. The structure, composition and function of the sheaths in Annelida and Arthropoda are examined and evidence for the separate evolutionary origins of myelin in the three clades is presented. That myelin has arisen independently at least three times, namely in Annelids, Arthropodas and Chordates, provides a remarkable example of convergent evolution.
The glia-derived extracellular matrix glycoprotein tenascin-C promotes embryonic and postnatal retina axon outgrowth via the alternatively spliced fibronectin type III domain TNfnD
Authors: Siddiqui Sonia , Horvat-Bröcker Andrea , Faissner Andreas
Published: June 2009

Tenascin-C (Tnc) is an astrocytic multifunctional extracellular matrix (ECM) glycoprotein that potentially promotes or inhibits neurite outgrowth. To investigate its possible functions for retinal development, explants from embryonic day 18 (E18) rat retinas were cultivated on culture substrates composed of poly-d-lysine (PDL), or PDL additionally coated with Tnc or laminin (LN)-1, which significantly increased fiber length. When combined with LN, Tnc induced axon fasciculation that reduced the apparent number of outgrowing fibers. In order to circumscribe the stimulatory region, Tnc-derived fibronectin type III (TNfn) domains fused to the human Ig-Fc-fragment TNfnD6-Fc, TNfnBD-Fc, TNFnA1A2-Fc and TNfnA1D-Fc were studied. The fusion proteins TNfnBD-Fc and to a lesser degree TNfnA1D-Fc were stimulatory when compared with the Ig-Fc-fragment protein without insert. In contrast, the combination TNfnA1A2-Fc reduced fiber outgrowth beneath the values obtained for the Ig-Fc domain, indicating potential inhibitory properties. The monoclonal J1/tn2 antibody (clone 578) that is specific for domain TNfnD blocked the stimulatory properties of the TNfn-Fc fusions. When postnatal day 7 retinal ganglion cells were used rather that explants, Tnc and Tnc-derived proteins proved permissive for neurite outgrowth. The present study highlights a strong retinal axon growth-promoting activity of the Tnc domain TNfnD, which is modulated by neighboring domains.
Wirksamkeit und Verträglichkeit einer Behandlung mit Acemetacin bei Patienten mit aktivierter Gonarthrose – Ergebnisse einer doppelblinden Vergleichsstudie mit Indometacin
Authors: Gallacchi  , Hodinka
Published: June 2009

137 Patienten mit aktivierter Gonarthrose wurden im Verhältnis 2:1 randomisiert und mit dem nicht­steroidalen Antirheumatikum Acemetacin 180 mg/die oder Indometacin 150 mg/die behandelt. Während der Behandlungsdauer von vier Wochen nahmen die Beschwerden – durch die Patienten mittels des Lequesne-Index beurteilt – in beiden Gruppen in vergleichbarem Ausmass ab. Dagegen fiel die Gesamtbeurteilung des Behandlungserfolges durch Patienten und Ärzte tendenziell zugunsten von Acemetacin aus: Unter Acemetacin waren bei 70%, unter Indometacin bei 51% der Patienten am Ende der Behandlung die Beschwerden deutlich gebessert oder abgeklungen. Bei den unerwünschten Ereignissen standen in beiden Gruppen Beschwerden seitens des Magen-Darmtrakts an erster Stelle. Infolge von unerwünschten Ereignissen brachen jedoch signifikant mehr Patienten die Behandlung mit Indometacin ab (22.2%) als mit Acemetacin (5.4%). 83% der Patienten schätzten die Verträglichkeit von Acemetacin als sehr gut oder gut ein, während dem in der Indometacin-Gruppe die Verträglichkeit nur von 56% der Patienten als gut oder sehr gut beurteilt wurde. Das Ergebnis war statistisch hoch signifikant (p = 0.0009). Die signifikant bessere Verträglichkeit von Acemetacin gegenüber Indometacin deckt sich mit den Erfahrungen aus früher durchgeführten klinischen Studien.
Nicht-epileptische paroxysmale Bewegungsstörungen des Säuglings
Authors: Ramelli  , Weber
Published: June 2009

Unter nicht-epileptischen paroxysmalen Bewegungsstörungen wird eine Gruppe von anfallsartigen und plötzlich auftretenden Ereignissen verstanden, die einen epileptischen Anfall imitieren können, sodass differentialdiagnostisch ein epileptischer Anfall klinisch nicht a priori ausgeschlossen werden kann. Paroxysmale Bewegungsstörungen kommen bei Säuglingen nicht selten vor, werden aber vermutlich in ihrer Häufigkeit unterschätzt. Diese Phänomene umfassen verschiedene klinische Situationen, die gemeinsam durch die unterbrochenen und episodischen Störungen der Bewegung gekennzeichnet sind. Klinische Erfahrung und eine detaillierte Anamnese, Verhaltensbeobachtung und Nutzung von Videoaufnahmen sind häufig wertvoll, um eine korrekte Diagnose zu stellen. In den meisten Fällen zeigen die paroxysmalen Bewegungsstörungen einen gutartigen Verlauf. Eine Behandlung ist nicht erforderlich. Es ist wichtig die Familien über die gute Prognose dieser Phänomene zu informieren. Der vorliegende Artikel informiert über diese Gruppe von Bewegungsstörungen des Säuglingsalters.
Hybrid Kelvin‐Helmholtz/Rayleigh‐Taylor instability in the plasma sheet
Authors: Yamamoto T.
Published: June 2009

This paper is to generalize the previous linear analysis of the hybrid Kelvin‐Helmholtz/Rayleigh‐Taylor (KH/RT) instability in a system of the magnetosphere‐ionosphere (M‐I) coupling, which is valid in the long‐wavelength limit of Lky ≪ 2, where ky is the azimuthal wave number and L stands for the scale length of a latitudinal profile in azimuthal velocity or energy density. For the first time, the linear growth rate profile of a hybrid wave can be revealed in an essentially overall range of ky. When the gradient of the energy density is directed inward (toward inner magnetic shells), the hybrid growth rate is positive (meaning growth) in a certain range of ky: 0 < Lky < m. As the inertial relaxation rate v approaches zero, the growth rate curve is close to the KH “spectrum” with m = 2, where v ≡ ΣP/Cm, the ratio between the inertial capacitance of the magnetospheric plasma and the height‐integrated Pedersen conductivity in the ionosphere. Without a velocity shear in the background flow, the spectrum much broadens, namely, the RT spectrum appears. The hybrid growth rate is shown to have a spectrum intermediate between the two ones of the corresponding KH and RT “root” instabilities. It is also found that the electrostatic KH instability is completely suppressed when the KH growth rate, estimated excluding the M‐I coupling, is less than v, which is a straightforward extension of that previous work. On the basis of the evaluation of Cm in the Tsyganenko model, electrostatic waves (with wavelengths greater than a few tens of kilometers at the ionospheric height) are unlikely to grow by the KH instability alone in the nighttime plasma sheet. Instead, hybrid waves can grow at the places where the particle energy density has an inward gradient. This fact may account for the frequent appearance of periodic auroral luminosity in a high‐latitude part of the nighttime oval as well as the formation of omega bands typically in the recovery phase of a substorm.
Aerosol size distribution modeling with the Community Multiscale Air Quality modeling system in the Pacific Northwest: 1. Model comparison to observations
Authors: Elleman Robert A. , Covert David S.
Published: June 2009

This paper evaluates aerosol number and mass concentrations from the Community Multiscale Air Quality (CMAQ) modeling system at the 4 km scale against detailed airborne and surface measurements from the coordinated Pacific Northwest 2001 and Pacific 2001 field campaigns. Several investigators have tested CMAQ's prediction of PM2.5 mass, but relatively little attention has been paid to its representation of other subranges of the particulate size distribution. In addition, few have examined CMAQ aerosol performance in the unique Pacific Northwest emission and meteorological conditions. Airborne measurements show an underprediction of aerosol number by a factor of 10–100, especially in the Aitken mode (i.e., ultrafine, <100 nm diameter). This result cannot simply be explained by errors in gas‐phase constituents. Errors in modeled ozone, NO, NOy, and SO2 exist, but the aerosol number underprediction is relatively constant while the gas‐phase errors fluctuate in time and location. For the period of aircraft measurements, the surface PM2.5 mass normalized mean bias is 2%, −33%, and –38%. Speciated aerosol measurements reveal a large but intermittent positive bias in aerosol nitrate and organic mass. Errors in aerosol mass and composition are not consistent or large enough to explain the negative bias factor of 5–10 in accumulation mode particle number concentration and of 10–100 in total particle number concentration. The few other studies of CMAQ size distributions have found similar performance, the root of which has many potential causes and is worthy of future investigation.