bluuebunny/crossref_metadata_2025 huggingface dataset:
Highly variable response to cytotoxic chemotherapy in carcinoma-associated fibroblasts (CAFs) from lung and breast
Authors: Sonnenberg Maike , van der Kuip Heiko , Haubeiß Silke , Fritz Peter , Schroth Werner , Friedel Godehard , Simon Wolfgang , Mürdter Thomas E , Aulitzky Walter E
Published: August 2009

Background

Carcinoma-associated fibroblasts (CAFs) can promote carcinogenesis and tumor progression. Only limited data on the response of CAFs to chemotherapy and their potential impact on therapy outcome are available. This study was undertaken to analyze the influence of chemotherapy on carcinoma-associated fibroblasts (CAFs)in vitroandin vivo.

Methods

Thein vivoresponse of stromal cells to chemotherapy was investigated in 22 neoadjuvant treated breast tumors on tissue sections before and after chemotherapy. Response to chemotherapy was analyzedin vitroin primary cultures of isolated CAFs from 28 human lung and 9 breast cancer tissues. The response was correlated toMdm2,ERCC1andTP53polymorphisms andTP53mutation status. Additionally, the cytotoxic effects were evaluated in anex vivoexperiment using cultured tissue slices from 16 lung and 17 breast cancer specimens.

Results

Nine of 22 tumors showed a therapy-dependent reduction of stromal activity. Pathological response of tumor or stroma cells did not correlate with clinical response. Isolated CAFs showed little sensitivity to paclitaxel. In contrast, sensitivity of CAFs to cisplatinum was highly variable with a GI50 ranging from 2.8 to 29.0 μM which is comparable to the range observed in tumor cell lines. No somaticTP53mutation was detected in any of the 28 CAFs from lung cancer tissue. In addition, response to cisplatinum was not significantly associated with the genotype ofTP53norMdm2andERCC1polymorphisms. However, we observed a non-significant trend towards decreased sensitivity in the presence ofTP53variant genotype. In contrast to the results obtained in isolated cell culture, in tissue slice culture breast cancer CAFs responded to paclitaxel within their microenvironment in the majority of cases (9/14). The opposite was observed in lung cancer tissues: only few CAFs were sensitive to cisplatinum within their microenvironment (2/15) whereas a higher proportion responded to cisplatinum in isolated culture.

Conclusion

Similar to cancer cells, CAF response to chemotherapy is highly variable. Beside significant individual/intrinsic differences the sensitivity of CAFs seems to depend also on the cancer type as well as the microenvironment.
Selecting short-statured children needing growth hormone testing: Derivation and validation of a clinical decision rule
Authors: Duché Laëtitia , Trivin Christine , Chemaitilly Wassim , Souberbielle Jean Claude , Bréart Gérard , Brauner Raja , Chalumeau Martin
Published: August 2009

Background

Numerous short-statured children are evaluated for growth hormone (GH) deficiency (GHD). In most patients, GH provocative tests are normal and are thus in retrospect unnecessary.

Methods

A retrospective cohort study was conducted to identify predictors of growth hormone (GH) deficiency (GHD) in children seen for short stature, and to construct a very sensitive and fairly specific predictive tool to avoid unnecessary GH provocative tests. GHD was defined by the presence of 2 GH concentration peaks < 10 ng/ml. Certain GHD was defined as GHD and viewing pituitary stalk interruption syndrome on magnetic resonance imaging. Independent predictors were identified with uni- and multi-variate analyses and then combined in a decision rule that was validated in another population.

Results

The initial study included 167 patients, 36 (22%) of whom had GHD, including 5 (3%) with certain GHD. Independent predictors of GHD were: growth rate < -1 DS (adjusted odds ratio: 3.2; 95% confidence interval [1.3–7.9]), IGF-I concentration < -2 DS (2.8 [1.1–7.3]) and BMI z-score ≥ 0 (2.8 [1.2–6.5]). A clinical decision rule suggesting that patients be tested only if they had a growth rate < -1 DS and a IGF-I concentration < -2 DS achieved 100% sensitivity [48–100] for certain GHD and 63% [47–79] for GHD, and a specificity of 68% [60–76]. Applying this rule to the validation population (n = 40, including 13 patients with certain GHD), the sensitivity for certain GHD was 92% [76–100] and the specificity 70% [53–88].

Conclusion

We have derived and performed an internal validation of a highly sensitive decision rule that could safely help to avoid more than 2/3 of the unnecessary GH tests. External validation of this rule is needed before any application.
Is it worth investing in mental health promotion and prevention of mental illness? A systematic review of the evidence from economic evaluations
Authors: Zechmeister Ingrid , Kilian Reinhold , McDaid David ,   the MHEEN group
Published: August 2009

Background

While evidence on the cost of mental illness is growing, little is known about the cost-effectiveness of programmes in the areas of mental health promotion (MHP) and mental disorder prevention (MDP). The paper aims at identifying and assessing economic evaluations in both these areas to support evidence based prioritisation of resource allocation.

Methods

A systematic review of health and non health related bibliographic databases, complemented by a hand search of key journals and analysis of grey literature has been carried out. Study characteristics and results were qualitatively summarised. Economic evaluations of programmes that address mental health outcome parameters directly, those that address relevant risk factors of mental illness, as well as suicide prevention interventions were included, while evaluations of drug therapies were excluded.

Results

14 studies fulfilled the inclusion criteria. They varied in terms of topic addressed, intervention used and study quality. Robust evidence on cost-effectiveness is still limited to a very small number of interventions with restricted scope for generalisability and transferability. The most favourable results are related to early childhood development programmes.

Conclusion

Prioritisation between MHP and MDP interventions requires more country and population-specific economic evaluations. There is also scope to retrospectively add economic analyses to existing effectiveness studies. The nature of promotion and prevention suggests that innovative approaches to economic evaluation that augment this with information on the challenges of implementation and uptake of interventions need further development.
THR Simulator – the software for generating radiographs of THR prosthesis
Authors: Wu Tai-Yin , Yang Rong-Sen , Fuh Chiou-Shann , Hou Sheng-Mou , Liaw Chen-Kun
Published: August 2009

Background

Measuring the orientation of acetabular cup after total hip arthroplasty is important for prognosis. The verification of these measurement methods will be easier and more feasible if we can synthesize prosthesis radiographs in each simulated condition. One reported method used an expensive mechanical device with an indeterminable precision. We thus develop a program, THR Simulator, to directly synthesize digital radiographs of prostheses for further analysis.

Under Windows platform and using Borland C++ Builder programming tool, we developed the THR Simulator. We first built a mathematical model of acetabulum and femoral head. The data of the real dimension of prosthesis was adopted to generate the radiograph of hip prosthesis. Then with the ray tracing algorithm, we calculated the thickness each X-ray beam passed, and then transformed to grey scale by mapping function which was derived by fitting the exponential function from the phantom image. Finally we could generate a simulated radiograph for further analysis.

Results

Using THR Simulator, the users can incorporate many parameters together for radiograph synthesis. These parameters include thickness, film size, tube distance, film distance, anteversion, abduction, upper wear, medial wear, and posterior wear. These parameters are adequate for any radiographic measurement research. This THR Simulator has been used in two studies, and the errors are within 2° for anteversion and 0.2 mm for wearing measurement.

Conclusion

We design a program, THR Simulator that can synthesize prosthesis radiographs. Such a program can be applied in future studies for further analysis and validation of measurement of various parameters of pelvis after total hip arthroplasty.
Using a human cardiovascular-respiratory model to characterize cardiac tamponade and pulsus paradoxus
Authors: Ramachandran Deepa , Luo Chuan , Ma Tony S , Clark John W
Published: August 2009

Background

Cardiac tamponade is a condition whereby fluid accumulation in the pericardial sac surrounding the heart causes elevation and equilibration of pericardial and cardiac chamber pressures, reduced cardiac output, changes in hemodynamics, partial chamber collapse, pulsus paradoxus, and arterio-venous acid-base disparity. Our large-scale model of the human cardiovascular-respiratory system (H-CRS) is employed to study mechanisms underlying cardiac tamponade and pulsus paradoxus. The model integrates hemodynamics, whole-body gas exchange, and autonomic nervous system control to simulate pressure, volume, and blood flow.

Methods

We integrate a new pericardial model into our previously developed H-CRS model based on a fit to patient pressure data. Virtual experiments are designed to simulate pericardial effusion and study mechanisms of pulsus paradoxus, focusing particularly on the role of the interventricular septum. Model differential equations programmed in C are solved using a 5th-order Runge-Kutta numerical integration scheme. MATLAB is employed for waveform analysis.

Results

The H-CRS model simulates hemodynamic and respiratory changes associated with tamponade clinically. Our model predicts effects of effusion-generated pericardial constraint on chamber and septal mechanics, such as altered right atrial filling, delayed leftward septal motion, and prolonged left ventricular pre-ejection period, causing atrioventricular interaction and ventricular desynchronization. We demonstrate pericardial constraint to markedly accentuate normal ventricular interactions associated with respiratory effort, which we show to be the distinct mechanisms of pulsus paradoxus, namely, series and parallel ventricular interaction. Series ventricular interaction represents respiratory variation in right ventricular stroke volume carried over to the left ventricle via the pulmonary vasculature, whereas parallel interaction (via the septum and pericardium) is a result of competition for fixed filling space. We find that simulating active septal contraction is important in modeling ventricular interaction. The model predicts increased arterio-venous CO2 due to hypoperfusion, and we explore implications of respiratory pattern in tamponade.

Conclusion

Our modeling study of cardiac tamponade dissects the roles played by septal motion, atrioventricular and right-left ventricular interactions, pulmonary blood pooling, and the depth of respiration. The study fully describes the physiological basis of pulsus paradoxus. Our detailed analysis provides biophysically-based insights helpful for future experimental and clinical study of cardiac tamponade and related pericardial diseases.
Elevated ethyl methanesulfonate (EMS) in nelfinavir mesylate (Viracept®, Roche): overview
Authors: Pozniak Anton , Müller Lutz , Salgo Miklos , Jones Judith K , Larson Peter , Tweats David
Published: August 2009

Roche's protease inhibitor nelfinavir mesylate (Viracept®) produced between March 2007-June 2007 was found to contain elevated levels of ethyl methanesulfonate (EMS), a known mutagen (alkylator) – leading to a global recall of the drug. EMS levels in a daily dose (2,500 mg Viracept/day) were predicted not to exceed a dose of ~2.75 mg/day (~0.055 mg/kg/day based on 50 kg patient). As existing toxicology data on EMS did not permit an adequate patient risk assessment, a comprehensive animal toxicology evaluation of EMS was conducted. General toxicity of EMS was investigated in rats over 28 days. Two studies for DNA damage were performed in mice; chromosomal damage was assessed using a micronucleus assay and gene mutations were detected using the MutaMouse transgenic model. In addition, experiments designed to extrapolate animal exposure to humans were undertaken. A general toxicity study showed that the toxicity of EMS occurred only at doses ≥ 60 mg/kg/day, which is far above that received by patients. Studies for chromosomal damage and mutations in mice demonstrated a clear threshold effect with EMS at 25 mg/kg/day, under chronic dosing conditions. Exposure analysis (Cmax) demonstrated that ~370-fold higher levels of EMS than that ingested by patients, are needed to saturate known, highly conserved, error-free, mammalian DNA repair mechanisms for alkylation. In summary, animal studies suggested that patients who took nelfinavir mesylate with elevated levels of EMS are at no increased risk for carcinogenicity or teratogenicity over their background risk, since mutations are prerequisites for such downstream events. These findings are potentially relevant to >40 marketed drugs that are mesylate salts.
cExternal beam radiation results in minimal changes in post void residual urine volumes during the treatment of clinically localized prostate cancer
Authors: Orio Peter F , Merrick Gregory S , Allen Zachariah A , Butler Wayne M , Wallner Kent E , Kurko Brian S , Galbreath Robert W
Published: August 2009

Background

To evaluate the impact of external beam radiation therapy (XRT) on weekly ultrasound determined post-void residual (PVR) urine volumes in patients with prostate cancer.

Methods

125 patients received XRT for clinically localized prostate cancer. XRT was delivered to the prostate only (n = 66) or if the risk of lymph node involvement was greater than 10% to the whole pelvis followed by a prostate boost (n = 59). All patients were irradiated in the prone position in a custom hip-fix mobilization device with an empty bladder and rectum. PVR was obtained at baseline and weekly. Multiple clinical and treatment parameters were evaluated as predictors for weekly PVR changes.

Results

The mean patient age was 73.9 years with a mean pre-treatment prostate volume of 53.3 cc, a mean IPSS of 11.3 and a mean baseline PVR of 57.6 cc. During treatment, PVR decreased from baseline in both cohorts with the absolute difference within the limits of accuracy of the bladder scanner. Alpha-blockers did not predict for a lower PVR during treatment. There was no significant difference in mean PVR urine volumes or differences from baseline in either the prostate only or pelvic radiation groups (p = 0.664 and p = 0.458, respectively). Patients with a larger baseline PVR (>40 cc) had a greater reduction in PVR, although the greatest reduction was seen between weeks one and three. Patients with a small PVR (<40 cc) had no demonstrable change throughout treatment.

Conclusion

Prostate XRT results in clinically insignificant changes in weekly PVR volumes, suggesting that radiation induced bladder irritation does not substantially influence bladder residual urine volumes.
Microdeletion of 6q16.1 encompassing EPHA7 in a child with mild neurological abnormalities and dysmorphic features: case report
Authors: Traylor Ryan N , Fan Zheng , Hudson Beth , Rosenfeld Jill A , Shaffer Lisa G , Torchia Beth S , Ballif Blake C
Published: August 2009

Background

Of the fewer than 100 cases reported within the literature of constitutional deletions involving the long arm of chromosome 6, only five have been characterized using high-resolution microarray analysis. Reported 6q deletion patients show a high incidence of mental retardation, ear anomalies, hypotonia, and postnatal growth retardation.

Results

We report a 16-month-old male presenting with developmental delay and dysmorphic features who was found by array-based comparative genomic hybridization (aCGH) to have a ~2.16 Mb de novo deletion within chromosome band 6q16.1 that encompasses only two genes. Expression studies of the mouse homologue of one of the genes, the ephrin receptor 7 gene (EPHA7), have shown the gene functions during murine embryogenesis to form cortical domains, determine brain size and shape, and play a role in development of the central nervous system (CNS).

Discussion

Our results suggest that deletion of EPHA7 plays a role in the neurologic and dysmorphic features, including developmental delay, hypotonia, and ear malformations, observed in some 6q deletion patients.
Whole genome sequencing of a single Bos taurusanimal for single nucleotide polymorphism discovery
Authors: Eck Sebastian H , Benet-Pagès Anna , Flisikowski Krzysztof , Meitinger Thomas , Fries Ruedi , Strom Tim M
Published: August 2009

Background

The majority of the 2 million bovine single nucleotide polymorphisms (SNPs) currently available in dbSNP have been identified in a single breed, Hereford cattle, during the bovine genome project. In an attempt to evaluate the variance of a second breed, we have produced a whole genome sequence at low coverage of a single Fleckvieh bull.

Results

We generated 24 gigabases of sequence, mainly using 36-bp paired-end reads, resulting in an average 7.4-fold sequence depth. This coverage was sufficient to identify 2.44 million SNPs, 82% of which were previously unknown, and 115,000 small indels. A comparison with the genotypes of the same animal, generated on a 50 k oligonucleotide chip, revealed a detection rate of 74% and 30% for homozygous and heterozygous SNPs, respectively. The false positive rate, as determined by comparison with genotypes determined for 196 randomly selected SNPs, was approximately 1.1%. We further determined the allele frequencies of the 196 SNPs in 48 Fleckvieh and 48 Braunvieh bulls. 95% of the SNPs were polymorphic with an average minor allele frequency of 24.5% and with 83% of the SNPs having a minor allele frequency larger than 5%.

Conclusions

This work provides the first single cattle genome by next-generation sequencing. The chosen approach - low to medium coverage re-sequencing - added more than 2 million novel SNPs to the currently publicly available SNP resource, providing a valuable resource for the construction of high density oligonucleotide arrays in the context of genome-wide association studies.
Presentation of human T cell leukemia virus type 1 (HTLV-1) Tax protein by dendritic cells: the underlying mechanism of HTLV-1-associated neuroinflammatory disease
Authors: Manuel Sharrón L , Schell Todd D , Acheampong Edward , Rahman Saifur , Khan Zafar K , Jain Pooja
Published: August 2009

DC function to prime anti-Tax CTL response in presence of HTLV-infected T cells, acute exposure to HTLV virions, or cell-free Tax.

HTLV-1 is the etiologic agent of a debilitating neurologic disorder, HAM/TSP. This disease features a robust immune response including the oligoclonal expansion of CD8+ CTLs specific for the viral oncoprotein Tax. The key pathogenic process resulting in the proliferation of CTLs and the presentation of Tax peptide remains uncharacterized. We have investigated the role of APCs, particularly DCs, in priming of the anti-Tax CTL response under in vitro and in vivo conditions. We investigated two routes (direct vs. indirect) of Tax presentation using live virus, infected primary CD4+/CD25+ T cells, and the CD4+ T cell line (C8166, a HTLV-1-mutated line that only expresses Tax). Our results indicated that DCs are capable of priming a pronounced Tax-specific CTL response in cell cultures consisting of naïve PBLs as well as in HLA-A*0201 transgenic mice (line HHD II). DCs were able to direct the presentation of Tax successfully through infected T cells, live virus, and cell-free Tax. These observations were comparable with those made with a known stimulant of DC maturation, a combination of CD40L and IFN-γ. Our studies clearly establish a role for this important immune cell component in HTLV-1 immuno/neuropathogenesis and suggest that modulation of DC functions could be an important tool for therapeutic interventions.
Seismic Performance of Sacrificial Exterior Shear Keys in Bridge Abutments
Authors: Silva Pedro F. , Megally Sami , Seible Frieder
Published: August 2009

Performance evaluation of sacrificial exterior shear keys in bridge abutments under simulated seismic loading was conducted in terms of damage levels that were observed during testing. These experiments provided results that were used to make realistic assumptions on the load-deformation response of as-built sacrificial exterior shear keys as well as their peak and post-peak performance under cyclic loads. Experimental results were subsequently used to develop a two-spring component hysteretic model for modeling the seismic response of shear keys at the abutments. The mathematical rules used to describe the hysteretic model are presented. Analyses show that this model was able to reproduce reasonably well the cyclic response of the investigated keys. The hysteretic model and key experimental results are presented in this paper.
Fragility and Qualification of Components Using Censored Seismic Demand Data
Authors: Nafday Avinash M.
Published: August 2009

Fragility functions are vital for the risk assessment of critical facilities and to calculate component probability of damage in performance-based earthquake engineering. Seismic qualification is used to prove the adequacy of components in existing facilities or to satisfy their design criteria in new facilities. This technical note describes an approach for component fragility development and seismic qualification using data for seismic demand experienced by similar components and their resulting performance. Depending on the observed component failure or survival, the seismic demand values either exceed or fall short of the random component capacity. The concept of censoring, which captures this excess or shortfall, is introduced to model such data and account for the different statistical characteristics of failure and survival data. The censored data are analyzed by survival analysis, which provides a rigorous and efficient approach to extract information from the data set.
Early requirement of Hyaluronan for tail regeneration inXenopustadpoles
Authors: Contreras Esteban G. , Gaete Marcia , Sánchez Natalia , Carrasco Héctor , Larraín Juan
Published: August 2009

Tail regeneration in Xenopus tadpoles is a favorable model system to understand the molecular and cellular basis of tissue regeneration. Although turnover of the extracellular matrix (ECM) is a key event during tissue injury and repair, no functional studies to evaluate its role in appendage regeneration have been performed. Studying the role of Hyaluronan(HA), an ECM component, is particularly attractive because it can activate intracellular signaling cascades after tissue injury. Here we studied the function of HA and components of the HA pathway in Xenopus tadpole tail regeneration. We found that transcripts for components of this pathway,including Hyaluronan synthase2 (HAS2), Hyaluronidase2 and its receptors CD44 and RHAMM,were transiently upregulated in the regenerative bud after tail amputation. Concomitantly, an increase in HA levels was observed. Functional experiments using 4-methylumbelliferone, a specific HAS inhibitor that blocked the increase in HA levels after tail amputation, and transgenesis demonstrated that the HA pathway is required during the early phases of tail regeneration. Proper levels of HA are required to sustain proliferation of mesenchymal cells in the regenerative bud. Pharmacological and genetic inhibition of GSK3βwas sufficient to rescue proliferation and tail regeneration when HA synthesis was blocked, suggesting that GSK3β is downstream of the HA pathway. We have demonstrated that HA is an early component of the regenerative pathway and is required for cell proliferation during the early phases of Xenopus tail regeneration. In addition, a crosstalk between HA and GSK3β signaling during tail regeneration was demonstrated.
Stage-dependent modes of Pax6-Sox2 epistasis regulate lens development and eye morphogenesis
Authors: Smith April N. , Miller Leigh-Anne , Radice Glenn , Ashery-Padan Ruth , Lang Richard A.
Published: August 2009

The transcription factors Pax6 and Sox2 have been implicated in early events in lens induction and have been proposed to cooperate functionally. Here, we investigated the activity of Sox2 in lens induction and its genetic relationship to Pax6 in the mouse. Conditional deletion of Sox2 in the lens placode arrests lens development at the pit stage. As previously shown, conditional deletion of Pax6 in the placode eliminates placodal thickening and lens pit invagination. The cooperative activity of Sox2 and Pax6 is illustrated by the dramatic failure of lens and eye development in presumptive lens conditional, compound Sox2, Pax6heterozygotes. The resulting phenotype resembles that of germ line Pax6 inactivation, and the failure of optic cup morphogenesis indicates the importance of ectoderm-derived signals for all aspects of eye development. We further assessed whether Sox2 and Pax6 were required for N-cadherin expression at different stages of lens development. N-cadherin was lost in Sox2-deficient but not Pax6-deficient pre-placodal ectoderm. By contrast, after the lens pit has formed, N-cadherin expression is dependent on Pax6. These data support a model in which the mode of Pax6-Sox2 inter-regulation is stage-dependent and suggest an underlying mechanism in which DNA binding site availability is regulated.
Zebrafishale oko, an essential determinant of sensory neuron survival and the polarity of retinal radial glia, encodes the p50 subunit of dynactin
Authors: Jing Xiaotang , Malicki Jarema
Published: August 2009

Although microtubule-dependent motors are known to play many essential functions in eukaryotic cells, their role in the context of the developing vertebrate embryo is less well understood. Here we show that the zebrafish ale oko (ako) locus encodes the p50 component of the dynactin complex. Loss of ako function results in a degeneration of photoreceptors and mechanosensory hair cells. Additionally, mutant Müller cells lose apical processes and their perikarya translocate rapidly towards the vitreal surface of the retina. This is accompanied by the accumulation of the apical determinants Nok and Has/aPKC in their cell bodies. ako is required cell-autonomously for the maintenance of the apical process but not for cell body positioning in Müller glia. At later stages, the retinotectal projection also degenerates in ako mutants. These results indicate that the p50 component of the dynactin complex is essential for the survival of sensory neurons and the maintenance of ganglion cell axons, and functions as a major determinant of apicobasal polarity in retinal radial glia.
Bicaudal C, a novel regulator of Dvl signaling abutting RNA-processing bodies, controls cilia orientation and leftward flow
Authors: Maisonneuve Charlotte , Guilleret Isabelle , Vick Philipp , Weber Thomas , Andre Philipp , Beyer Tina , Blum Martin , Constam Daniel B.
Published: August 2009

Polycystic diseases and left-right (LR) axis malformations are frequently linked to cilia defects. Renal cysts also arise in mice and frogs lacking Bicaudal C (BicC), a conserved RNA-binding protein containing K-homology (KH)domains and a sterile alpha motif (SAM). However, a role for BicC in cilia function has not been demonstrated. Here, we report that targeted inactivation of BicC randomizes left-right (LR) asymmetry by disrupting the planar alignment of motile cilia required for cilia-driven fluid flow. Furthermore,depending on its SAM domain, BicC can uncouple Dvl2 signaling from the canonical Wnt pathway, which has been implicated in antagonizing planar cell polarity (PCP). The SAM domain concentrates BicC in cytoplasmic structures harboring RNA-processing bodies (P-bodies) and Dvl2. These results suggest a model whereby BicC links the orientation of cilia with PCP, possibly by regulating RNA silencing in P-bodies.
Development of a DVD pickup-based four-degrees- of-freedom motion error measuring system for a single-axis linear moving platform
Authors: Huang H-L , Liu C-H , Jywe W-Y , Wang M-S , Jeng Y-R , Duan L-L , Hsu T-H
Published: August 2009

In this study, a simple and high-resolution four-degrees-of-freedom (4-DOF) motion error measuring system based on DVD pickup has been proposed. It can simultaneously measure the horizontal straightness error and three angular errors of a single-axis linear moving platform. The horizontal straightness error is measured based on the focus technique of DVD pickup and the inverse algorithm is used to solve pitch, yaw, and roll angular errors through the kinematic analysis. The grating is mounted on the moving axis of a single-axis linear moving platform and reflects incident laser beam into several diffractive rays. Photodiode IC (PDIC) of DVD pickup is set up for detecting the focus error signal (FES) of zero-order diffraction ray from grating and quadrant detectors are set up for detecting the position of ±1st-order diffraction rays from grating. The 4-DOF motion error measuring system detected the three angular errors with a related accuracy of about ±1 arc sec for a measuring range of ±100 arc sec, and detected horizontal straightness with a related accuracy of about ±2 μm for a measuring range of ±150 μm.
Finite-element-based hybrid dynamic cutting model for aluminium alloy milling
Authors: Asad M , Mabrouki T , Rigal J-F
Published: August 2009

The present contribution deals with milling tool vibration effects on chip morphology, cutting force, and cut surface topology. The study concerns an orthogonal down-cut peripheral milling case for aeronautic aluminium alloy A2024-T351. A finite-element-based hybrid dynamic cutting model (HDC model) is proposed to predict the chip morphology under dynamic cutting conditions. The latter is conceived with commercial software ABAQUS®/EXPLICIT and combines the stiffness of a high-speed milling spindle system (tool, toolholder, and rotor) with the chip formation process. A qualitative parametric study with various stiffness and damping coefficient values for a high-speed milling spindle system has been performed. The results concerning chip morphology and cutting force are compared with experimental data, while the surface profiles are compared with those obtained by considering a perfectly rigid spindle system. As expected, a less rigid undamped milling system generates higher-amplitude tool vibrations during milling. In this situation, the temperature rises at the tool—workpiece interface, enhancing material softening. This softening promotes chip segmentation and increases waviness of the machined surface profile. The numerical results show that higher values of cutting speed and uncut chip thickness are associated with higher vibration amplitudes.
High-speed milling of AISI H13 hot-work tool steel using polycrystalline cubic boron nitride ball-nose mills: From experimental investigations and empirical modelling to functional testing of the machined surfaces
Authors: Axinte D , Dewes R
Published: August 2009

Owing to continuous development of composite materials, the properties of polycrystalline cubic boron nitride (PCBN) can be engineered to enable their use for the manufacture of cutting edges for high-speed machining applications. This paper reports on an ‘integrative’ approach, i.e. cutting parameters—tool performance—surface integrity and residual stresses—tribological and fatigue assessment, of the high-speed milling (HSM) of AISI H13 hot-work tool steel using PCBN ball-nose end milling cutters. The experimental trials followed an experimental design (factors: cutting speed, feed per tooth, workpiece tilt angle) on which a set of key process output measures was examined: tool life, surface roughness, metallurgical integrity, microhardness, and residual stresses. Where significant variations in the output measures with the changes in the operating parameters were found, empirical models were generated; this is of particular importance for the mould/die industry to enable the prediction of critical process measures such as tool flank wear, surface roughness, and residual stresses under machined surfaces without the need for repeated measurements. It was found that only a compromise of the ‘near-best’ values of the output measures can be obtained by employing a ‘pseudo-optimal’ set of cutting parameters. Further, functional tests carried out on HSM surfaces with ‘near-best’ output measures using PCBN tools showed that superior fatigue performance (approximately 30 per cent) is expected for moulds/dies when compared with those obtained via the conventional manufacturing route (electrical discharge machining and polishing).
The effect of E20 ethanol fuel on vehicle emissions
Authors: Hilton B , Duddy B
Published: August 2009

E20 fuel research conducted by the Rochester Institute of Technology has focused on vehicle exhaust, vehicle drivability and vehicle maintenance. Beginning in February 2008, ten older gasoline vehicles owned and operated by Monroe County, New York State, were evaluated using E20 fuel. Criteria pollutant tailpipe emissions from running E20 versus gasoline were tested using the FTP-75 Federal Test Procedure in an independent vehicle emissions laboratory. Initial results demonstrated significant fleet tailpipe emissions reductions in carbon monoxide and total hydrocarbons when running E20 versus gasoline. The fleet has currently operated a total of more than 100000 miles on E20, with individual vehicles having been driven at least 2400 miles each on E20 at the time of testing. Driveability and maintenance have been unaffected. Driver comments were strongly positive. Research continues, with future work to include repeat tailpipe emissions testing for degradation and expanding E20 fuel usage to the entire Monroe County vehicle fleet. This paper presents the initial results for the vehicle tailpipe emissions testing on gasoline versus E20.
Adaptive neuro-fuzzy controllers for an open-loop morphing wing system
Authors: Grigorie T L , Botez R M , Popov A V
Published: August 2009

A new method for the realization of two neuro-fuzzy controllers for a morphing wing design application is presented here. The controllers' main function is to correlate each set of pressure differences, calculated between the optimized and the reference airfoil, with each of the airfoil deformations produced by the actuators' system. The pressures are calculated at different chord positions and will also be measured during wind tunnel tests. During a first identification phase, the two fuzzy inference systems (FISs) from the controllers' structure are generated for 16 flight conditions characterized by Mach numbers and angles of attack. Next, the FIS are optimized with the Matlab function adaptive neuro-fuzzy inference system (ANFIS) by training over different epochs. Finally, the controllers are validated for the other 33 flight conditions of the open-loop morphing wing system. This is the first time that such a method of relating the pressure differences to airfoil displacements has been conceived and used in an open-loop morphing wing controller system.
Cooperative path planning and task assignment for unmanned air vehicles
Authors: Innocenti M , Pollini L , Bracci A
Published: August 2009

This article presents a review and a novel approach to the decentralized path planning and task assignment for multiple cooperative unmanned air systems, in multiple target, and multiple task environment. The vehicles (or agents) may have complete or partial a priori information about the targets that populate the scenario. Each vehicle autonomously computes the cost for servicing each task available at each target using a path planning algorithm, taking into account obstacles, pop-up threats, and weights the total path cost including potential risk areas. Vehicles assign an initial ranking to each task, and then exchange their ranking information with the others. Each agent then updates the ranking of its tasks using a non-linear dynamic programming algorithm that is proven to be stable and to converge to an equilibrium point where each vehicle is assigned to a different task. The ranking dynamics is initially formulated as a continuous time system, and then time-discretized depending on available data, and transmission rate among the network. Stability of the network and independence of steady-state values from the data rate are evaluated analytically, and via simulation.
Dynamic tracking of the scapula using skin-mounted markers
Authors: Lovern B , Stroud L A , Evans R O , Evans S L , Holt C A
Published: August 2009

The shoulder complex is prone to numerous pathologies and instabilities due to its large range of motion. The extent of injury is assessed through a series of observations and physical examinations. It is hypothesized that objective kinematic analysis of the shoulder could yield useful functional insights to aid clinical practice. Non-invasive motion analysis techniques to monitor shoulder function have been developed using passive markers; however, accurate measurement of scapula kinematics is problematic because of overlying tissue. The scapula locator is the accepted standard by which alternative non-invasive techniques of scapula tracking are validated. In this study, the viability of using skin-mounted markers to measure dynamic scapula movement is determined. Complete kinematic descriptions of ten healthy shoulders were obtained. Elevations of the glenohumeral joint were similar with both techniques, indicating that the skin marker method is suitable for gathering functional glenohumeral data. The main differences of note are seen at the scapulothoracic articulation where the skin marker method underestimated lateral rotation by more than 50° at maximum elevation. However, the correlation between the two approaches is greater than 0.7, suggesting that it may be possible to derive linear regression models to predict dynamic scapulothoracic lateral rotation accurately using skin-mounted scapula markers.
Active constraint control for image-guided robotic surgery
Authors: Yen P-L , Davies B L
Published: August 2009

The concept of active constraint control for image-guided robotic surgery is introduced, together with its benefits and a short outline of its history. The clinical use of active constraint control in orthopaedic surgery is discussed, together with the outcomes of a clinical trial for unicondylar knee replacement surgery. The evolution of the robotic design from large costly structures towards simpler, more cost-effective systems is also presented, leading to the design of the Acrobot ‘Sculptor’ system. A new approach to the achievement of robotic total knee replacement is also presented, in which a high-speed rotary cutter is used to slice through the bone to achieve a speedy resection. The control concept is presented, together with the results of trials on animal bones and a cadaver, showing that it is possible to remove large quantities of bone both quickly and accurately.
Experimental identification of rigid body inertia properties using single-rotor unbalance excitation
Authors: Kloepper R , Okuma M
Published: August 2009

This article proposes a new experimental method for the identification of rigid body inertia properties. The test structure is suspended in an elastic wire and excited by a single-rotor unbalance actuator. Unlike a conventional shaker or impulse actuator, the proposed actuator can be rigidly attached to the test structure, whereby accurate alignment is made relatively easy. Moreover, because of a sensorless single-rotor design, the actuator can be built at minimal cost. Both the excitation force and the rotation frequency required as feedback to control the actuator are derived from the structure's acceleration response signal; as a result, the experiment requires no sensors other than one accelerometer. The acceleration response measurements are used in an identification algorithm based on models of the unknown rigid body inertia properties and of the suspension properties. In the process of identifying the inertia properties, the suspension model prevents errors otherwise caused by suspension and gravity effects. The proposed method was applied to two test cases: a beam structure and an assembled motorcycle frame and engine. In both cases, accurate rigid body properties could be identified.
TEMPO-Mediated Oxidation of Primary Alcohols to Carboxylic Acids by Exploitation of Ethers in an Aqueous–Organic Biphase System
Authors: Mei Zhen-Wu , Ma Li-Jian , Kawafuchi Hiroyuki , Okihara Takumi , Inokuchi Tsutomu
Published: August 2009

Expeditious and benign methods for primary alcohol–carboxylic acid conversions with TEMPO were developed in a biphasic system composed of a slightly miscible ether (THP) and aqueous layer. Easily available co-oxidants such as Py·HBr3, Bu4NBr3, and electrooxidation were successfully applied to generate N-oxoammonium species as a recyclable catalyst.
Activity Enhancement of WO3-Promoted Ir/SiO2 Catalysts by High-Temperature Calcination for the Selective Reduction of NO with CO
Authors: Haneda Masaaki , Aoki Naoya , Arimitsu Kouji , Hamada Hideaki
Published: August 2009

The catalytic activity of WO3-promoted Ir/SiO2 for the selective reduction of NO with CO in the presence of excess O2 is strongly dependent on the catalyst calcination conditions in the preparation process. WO3/Ir/SiO2 catalyst prepared by air calcination showed higher activity than that prepared by H2 reduction. The activity of WO3/Ir/SiO2 catalyst prepared by air calcination was also found to increase with increasing calcination temperature up to 1073 K; however, a further increase in the temperature to 1173 K caused a decrease in the NO reduction activity, although very high selectivity was observed for this catalyst. The lack of a major difference in the apparent activation energy for NO reduction suggests that NO reduction occurs at the same reaction sites, irrespective of calcination temperature. On the other hand, the apparent activation energy for CO oxidation increased with increased calcination temperature, suggesting that the reaction sites for CO oxidation change according to calcination temperature. Catalyst characterizations revealed that iridium species interacting strongly with WO3 are preferentially created by high-temperature air calcination. A combination of partially reduced iridium species (IrO2−x) and WO3 (IrO2−x–WO3) was concluded to act as catalytically active sites of WO3/Ir/SiO2 for NO reduction.
Change in Molecular Orientation with Condensation of 4,4′-Bis(trihydroxysilyl)biphenyl Crystals
Authors: Ohashi Masataka , Goto Yasutomo , Mizoshita Norihiro , Ohsuna Tetsu , Tani Takao , Inagaki Shinji
Published: August 2009

Molecular orientation in 4,4′-bis(trihydroxysilyl)biphenyl plate-like square crystals (BPSi) and orientation change with heating-induced condensation were investigated using polarization optical microscopy. The biphenylylene groups in BPSi were arranged along a diagonal of the square plane with a tilt angle of 21° from the planar normal. This arrangement was maintained up to 200 °C for several minutes, but heating at 250 °C promoted a condensation reaction which formed siloxane bonds, causing changes in molecular orientation to a tilt angle of 0°, and altering the shape of BPSi crystals from square to rhombic. The molecular arrangement and its change after condensation were qualitatively confirmed by molecular-mechanics simulation. The absorption and fluorescence bands of the biphenylylene groups were significantly red-shifted by the condensation due to the change in molecular arrangement, which resulted from a notable decrease in biphenylylene–biphenylylene separation.
Langmuir–Blodgett Films of Charge-Transfer Complexes: Ethylenedithio-Substituted Amphiphilic Bis-TTF Macrocycle and F4TCNQ or Br2TCNQ
Authors: Endo Toru , Akutagawa Tomoyuki , Kajiwara Teppei , Kakiuchi Keiko , Tatewaki Yoko , Noro Shin-ichiro , Nakamura Takayoshi
Published: August 2009

Charge-transfer (CT) complexes between ethylenedithio-substituted bis-TTF macrocycle 1a, as an amphiphilic electron donor, and 7,7,8,8-tetracyano-p-quinodimethane (TCNQ) derivatives, as electron acceptors, were fabricated as Langmuir–Blodgett (LB) films. For the 1a–F4TCNQ LB film deposited at a surface pressure of 5 mN m−1 onto a substrate surface, the stoichiometry between the donor and acceptor was determined as 1:2 using XPS measurements. In contrast, a donor/acceptor ratio of 1:0.3 was observed for the 1a–Br2TCNQ LB film, indicating that a fraction of Br2TCNQ was lost during the LB film formation process. Similarity of the round-shaped domains that cover the surfaces of the 1a–Br2TCNQ and neutral 1a LB films indicates the presence of neutral 1a within the 1a–Br2TCNQ LB film. For the (1a2+)(F4TCNQ−)2 LB film, the presence of a CN-stretching frequency signifies the formation of a fully ionic electronic ground state. The LB film of 1a–Br2TCNQ exhibited a broad absorption at ca. 3 × 103 cm−1, which is characteristic of an intermolecular CT transition for a partial CT state. 1a–Br2TCNQ LB film consisted of neutral 1a and CT complex of 1a–Br2TCNQ. The room temperature conductivity of the 1a–Br2TCNQ LB film (1.2 × 10−2 S cm−1) was two orders of magnitude higher than that of 1a–F4TCNQ (3.9 × 10−4 S cm−1).
Co-transcriptional splicing of constitutive and alternative exons
Authors: Pandya-Jones Amy , Black Douglas L.
Published: August 2009

In metazoan organisms, pre-mRNA splicing is thought to occur during transcription, and it is postulated that these two processes are functionally coupled via still-unknown mechanisms. Current evidence supports co-transcriptional spliceosomal assembly, but there is little quantitative information on how much splicing is completed during RNA synthesis. Here we isolate nascent chromatin-associated RNA from free, nucleoplasmic RNA already released from the DNA template. Using a quantitative RT-PCR assay, we show that the majority of introns separating constitutive exons are already excised from the human c-Src and fibronectin pre-mRNAs that are still in the process of synthesis, and that these introns are removed in a general 5′-to-3′ order. Introns flanking alternative exons in these transcripts are also removed during synthesis, but show differences in excision efficiency between cell lines with different regulatory conditions. Our data suggest that skipping of an exon can induce a lag in splicing compared to intron removal under conditions of exon inclusion. Nevertheless, excision of the long intron encompassing the skipped exon is still completed prior to transcript release into the nucleoplasm. Thus, we demonstrate that the decision to include or skip an alternative exon is made during transcription and not post-transcriptionally.
Integer Knapsacks: Average Behavior of the Frobenius Numbers
Authors: Aliev Iskander , Henk Martin
Published: August 2009

The largest integer that cannot be represented as a nonnegative integral combination of given set of positive integers is called the Frobenius number of these integers. We show that the asymptotic growth of the Frobenius number on average is significantly slower than the growth of the maximum Frobenius number.
Taxonomic revision of Gracilaria “verrucosa” from the Russian Far East based on morphological and molecular data
Authors: Skriptsova Anna V. , Choi Han-Gu
Published: August 2009

Gracilaria “verrucosa” is now regarded an invalid name, with G. gracilis being used in recent studies of the genus from the Russian coast of the East Sea (Sea of Japan). This has created nomenclatural confusion for members of the genus in this region. Here we revise the taxonomy of G. “verrucosa” from Peter the Great Bay (East Sea, Russia) based on morpho-anatomical characters and comparisons of nuclear small subunit rDNA, plastid rbcL and mitochondrial cox1 sequence data. No differences were found between sequences for attached and unattached forms of G. “verrucosa”. Molecular data also indicate that G. “verrucosa” from Peter the Great Bay is conspecific with Gracilaria vermiculophylla from the northwestern Pacific, and the Russian population is closely related to Korean-Japanese populations from the East Sea rather than with populations on the Pacific coast of Japan.