bluuebunny/crossref_metadata_2025_split huggingface dataset:
The input–output weight enumeration of binary Hamming codes
Authors: Loskot Pavel , Beaulieu Norman C. 
Published: June 2006

AbstractWe show that binary Hamming codes can be constructed recursively. The recursive structure is used to efficiently enumerate the input–output weights. Hence, the bit error rate of binary Hamming codes with antipodal signalling and hard‐decision demodulation used on additive white Gaussian noise channels can be evaluated exactly. The numerically computed coding gain of Hamming codes reveals a surprising fact that the coding gain is not monotonically increasing with signal‐to‐noise ratio. Copyright © 2006 AEIT
Analysis of integrated power control and advanced receivers algorithms
Authors: Novakovic Dejan M. , Dukic Miroslav L. 
Published: June 2006

AbstractIntegrated power control algorithms with advanced receivers like adaptive antenna arrays and multiuser detectors have significantly better performance than conventional power control algorithms with matched filters. However, these algorithms are very complex for practical implementation and their significant performance gains were only shown in idealised conditions. In this paper, we study the performance of integrated power control and advanced receivers algorithms for WCDMA uplink that are modified to be more suitable for practical implementation. We simultaneously take into account system imperfections, such as limited bandwidth for power control command, power control command errors, update rate of power control command, delay of power control command, fast fading effects, soft handover, limitation of mobile user minimum and maximum power, etc. Impact of mobile user velocities and errors in filter coefficients determination on performance of the algorithms are also shown. We show that also in this environment, power control algorithms integrated with advanced receivers significantly outperform conventional power control algorithm. Copyright © 2006 AEIT
Bayesian estimation of evoked and induced responses
Authors: Friston Karl , Henson Richard , Phillips Christophe , Mattout Jérémie 
Published: June 2006

AbstractWe describe an extension of our empirical Bayes approach to magnetoencephalography/electroencephalography (MEG/EEG) source reconstruction that covers both evoked and induced responses. The estimation scheme is based on classical covariance component estimation using restricted maximum likelihood (ReML). We have focused previously on the estimation of spatial covariance components under simple assumptions about the temporal correlations. Here we extend the scheme, using temporal basis functions to place constraints on the temporal form of the responses. We show how the same scheme can estimate evoked responses that are phase‐locked to the stimulus and induced responses that are not. For a single trial the model is exactly the same. In the context of multiple trials, however, the inherent distinction between evoked and induced responses calls for different treatments of the underlying hierarchical multitrial model. We derive the respective models and show how they can be estimated efficiently using ReML. This enables the Bayesian estimation of evoked and induced changes in power or, more generally, the energy of wavelet coefficients. Hum Brain Mapp, 2006. © 2006 Wiley‐Liss, Inc.
ATM is activated by mitotic stress and suppresses centrosome amplification in primary but not in tumor cells
Authors: Shen Kate , Wang Yaolin , Brooks S.C. , Raz Avraham , Wang Y. Alan 
Published: June 2006

AbstractCentrosome amplification has been proposed to contribute to the development of aneuploidy and genome instability. Here, we show that Ataxia‐Telangiectasia Mutated (ATM) is localized to the centrosome and co‐purified with γ‐tubulin. The importance of ATM in centrosome duplication is demonstrated in Atm‐deficient primary mouse embryonic fibroblasts that display centrosome amplification. Interestingly, centrosome amplification was not observed in tumor cell lines derived from Atm and p21 double deficient mouse. Our results also indicate that both p53 and p21 operate in the same pathway as ATM in regulating centrosome biogenesis. Finally, a potential role of ATM in spindle checkpoint regulation is demonstrated by which ATM protein is activated by mitotic stress. These results suggest a role of ATM in spindle checkpoint regulation and indicate that ATM suppresses genome instability and cellular transformation by regulating centrosome biogenesis. J. Cell. Biochem. 99: 1267–1274, 2006. © 2006 Wiley‐Liss, Inc.
High glucose increase cell cycle regulatory proteins level of mouse embryonic stem cells via PI3‐K/Akt and MAPKs signal pathways
Authors: Kim Yun Hee , Heo Jung Sun , Han Ho Jae 
Published: June 2006

AbstractThis study examined the effects of high glucose on cell proliferation and its related signal pathways using mouse embryonic stem (ES) cells. Here, we showed that high glucose level significantly increased [3H]thymidine incorporation, BrdU incorporation, the number of cells, [3H]leucine, and [3H]proline incorporation in a time‐(>3 hr) and dose‐(>25 mM) dependent manner. Moreover, high glucose level increased the cellular reactive oxygen species (ROS), Akt, and mitogen‐activated protein kinases (MAPKs) phosphorylation. Subsequently, these signaling molecules involved in high glucose‐induced increase of [3H]thymidine incorporation. High glucose level also increased cyclin D1, cyclin E, cyclin‐dependent kinase (CDK) 2, and CDK 4 protein levels, which is cell cycle regulatory proteins acting in G1–S phase of cell cycle. Inhibition of phosphatidylinositol 3‐kinase (PI3‐K) (LY 294002: PI3‐kinase inhibitor, 10−6 M), Akt (Akt inhibitor, 10−5 M), and p44/42 MAPKs (PD 98059: MEK inhibitor, 10−5 M) decreased these proteins. High glucose level phosphorylated the RB protein, which was decreased by inhibition of PI3‐K and Akt. In conclusion, high glucose level stimulates mouse ES cell proliferation via the PI3‐K/Akt and MAPKs pathways. J. Cell. Physiol. 209: 94–102, 2006. © 2006 Wiley‐Liss, Inc.
Modular, self‐assembling peptide linkers for stable and regenerable carbon nanotube biosensor interfaces
Authors: Contarino Mark R. , Sergi Mauro , Harrington Adrian E. , Lazareck Adam , Xu Jimmy , Chaiken Irwin 
Published: June 2006

AbstractAs part of an effort to develop nanoelectronic sensors for biological targets, we tested the potential to incorporate coiled coils as metallized, self‐assembling, site‐specific molecular linkers on carbon nanotubes (CNTs). Based on a previously conceived modular anchor‐probe approach, a system was designed in which hydrophobic residues (valines and leucines) form the interface between the two helical peptide components. Charged residues (glutamates and arginines) on the borders of the hydrophobic interface increase peptide solubility, and provide stability and specificity for anchor‐probe assembly. Two histidine residues oriented on the exposed hydrophilic exterior of each peptide were included as chelating sites for metal ions such as cobalt. Cysteines were incorporated at the peptide termini for oriented, thiol‐mediated coupling to surface plasmon resonance (SPR) biosensor surfaces, gold nanoparticles or CNT substrates. The two peptides were produced by solid phase peptide synthesis using Fmoc chemistry: an acidic 42‐residue peptide E42C, and its counterpart in the heterodimer, a basic 39‐residue peptide R39C. The ability of E42C and R39C to bind cobalt was demonstrated by immobilized metal affinity chromatography and isothermal titration calorimetry. SPR biosensor kinetic analysis of dimer assembly revealed apparent sub‐nanomolar affinities in buffers with and without 1 mM CoCl2 using two different reference surfaces. For device‐oriented CNT immobilization, R39C was covalently anchored to CNT tips via a C‐terminal cysteine residue. Scanning electron microscopy was used to visualize the assembly of probe peptide (E42C) N‐terminally labeled with 15 nm gold nanoparticles, when added to the R39C‐CNT surface. The results obtained open the way to develop CNT tip‐directed recognition surfaces, using recombinant and chemically synthesized chimeras containing binding epitopes fused to the E42C sequence domain. Copyright © 2006 John Wiley & Sons, Ltd.
Real‐time monitoring of the membrane‐binding and insertion properties of the cholesterol‐dependent cytolysin anthrolysin O from Bacillus anthracis
Authors: Cocklin Simon , Jost Monika , Robertson Noreen M , Weeks Stephen D , Weber Hans‐Walter , Young Emily , Seal Samar , Zhang Can , Mosser Elise , Loll Patrick J , Saunders Aleister J , Rest Richard F , Chaiken Irwin M 
Published: June 2006

AbstractBacillus anthracis has recently been shown to secrete a potently hemolytic/cytolytic protein that has been designated anthrolysin O (ALO). In this work, we initiated a study of this potential anthrax virulence factor in an effort to understand the membrane—binding properties of this protein. Recombinant anthrolysin O (rALO35–512) and two N‐terminally truncated versions of ALO (rALO390–512 and rALO403–512) from B. anthracis were overproduced in Escherichia coli and purified to homogeneity. The role of cholesterol in the cytolytic activity of ALO was probed in cellular cholesterol depletion assays using mouse and human macrophage‐like lines, and also Drosophila Schneider 2 cells. Challenging the macrophage cells with rALO35–512, but not rALO390–512 or rALO403–512, resulted in cell death by lysis, with this cytolysis being abolished by depletion of the membrane cholesterol. Drosophila cells, which contain ergosterol as their major membrane sterol, were resistant to rALO‐mediated cytolysis. In order to determine the molecular mechanism of this resistance, the interaction of rALO with model membranes comprised of POPC alone, or with a variety of structurally similar sterols including ergosterol, was probed using Biacore. Both rALO35–512 and rALO403–512 demonstrated robust binding to model membranes composed of POPC and cholesterol, with amount of protein bound proportional to the cholesterol content. Ergosterol supported greatly reduced binding of both rALO35–512 and rALO403–512, whereas other sterols tested did not support binding. The rALO403–512—membrane interaction demonstrated an equilibrium dissociation constant (KD) in the low nanomolar range, whereas rALO35–512 exhibited complex kinetics likely due to the multiple events involved in pore formation. These results establish the pivotal role of cholesterol in the action of rALO. The biosensor method developed to measure ALO recognition of cholesterol in a membrane environment could be extended to provide a platform for the screening of inhibitors of other membrane‐binding proteins and peptides. Copyright© 2006 John Wiley & Sons, Ltd.
Age‐dependent changes in matrix composition and organization at the ligament‐to‐bone insertion
Authors: Wang I‐Ning E. , Mitroo Siddarth , Chen Faye H. , Lu Helen H. , Doty Stephen B. 
Published: June 2006

AbstractInjuries to the anterior cruciate ligament (ACL) often occur at the ligament‐to‐bone insertion site; thus, an in‐depth understanding of the native insertion is critical in identifying the etiology of failure and devising optimal treatment protocols for ACL injuries. The objective of this study is to conduct a systematic characterization of the ACL‐to‐bone interface, focusing on structural and compositional changes as a function of age. Using a bovine model, three age groups were studied: Neonatal (1–7 days old), Immature (2–6 months old), and Mature (2–5 years old). The distribution of types I, II, X collagen, decorin, cartilage oligomeric matrix protein (COMP), glycosaminoglycan (GAG), alkaline phosphatase (ALP) activity, and minerals at the ACL‐to‐bone insertion were examined. Additionally, cell aspect ratio, size, and distribution across the insertion were quantified. The ACL‐to‐bone insertion is divided into four regions: ligament, nonmineralized interface, mineralized interface, and bone. Both region‐dependent and age‐dependent structural and compositional changes at the insertion site were observed in this study. The interface in the skeletally immature group resembled articular cartilage, while the adult interface was similar to fibrocartilaginous tissue. Age‐dependent changes in extracellular matrix composition (type X collagen, sulfated glycosaminoglycan), cellularity, ALP activity, and mineral distribution were also found. Marked differences in collagen fiber orientation between the femoral and tibial insertions were observed, and these differences became more pronounced with age. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:1745–1755, 2006
Relative contributions of muscle activation and muscle size to plantarflexor torque during rehabilitation after immobilization
Authors: Stevens Jennifer E. , Pathare Neeti C. , Tillman Susan M. , Scarborough Mark T. , Gibbs C. Parker , Shah Prithvi , Jayaraman Arun , Walter Glenn A. , Vandenborne Krista 
Published: June 2006

AbstractMuscle atrophy is clearly related to a loss of muscle torque, but the reduction in muscle size cannot entirely account for the decrease in muscle torque. Reduced neural input to muscle has been proposed to account for much of the remaining torque deficits after disuse or immobilization. The purpose of this investigation was to assess the relative contributions of voluntary muscle activation failure and muscle atrophy to loss of plantarflexor muscle torque after immobilization. Nine subjects (ages 19–23) years with unilateral ankle malleolar fractures were treated by open reduction‐internal fixation and 7 weeks of cast immobilization. Subjects participated in 10 weeks of rehabilitation that focused on both strength and endurance of the plantarflexors. Magnetic resonance imaging, isometric plantarflexor muscle torque and activation (interpolated twitch technique) measurements were performed at 0, 5, and 10 weeks of rehabilitation. Following immobilization, voluntary muscle activation (56.8 ± 16.3%), maximal cross‐sectional area (CSA) (35.3 ± 7.6cm2), and peak torque (26.2 ± 12.7N‐m) were all significantly decreased ( p < 0.0056) compared to the uninvolved limb (98.0 ± 2.3%, 48.0 ± 6.8 cm2, and 105.2 ± 27.0 N‐m, respectively). During 10 weeks of rehabilitation, muscle activation alone accounted for 56.1% of the variance in torque ( p < 0.01) and muscle CSA alone accounted for 35.5% of the variance in torque ( p < 0.01). Together, CSA and muscle activation accounted for 61.5% of the variance in torque ( p < 0.01). The greatest gains in muscle activation were made during the first 5 weeks of rehabilitation. Both increases in voluntary muscle activation and muscle hypertrophy contributed to the recovery in muscle strength following immobilization, with large gains in activation during the first 5 weeks of rehabilitation. In contrast, muscle CSA showed fairly comparable gains throughout both the early and later phase of rehabilitation. Published by Wiley Periodicals, Inc. J Orthop Res 24:1729–1736, 2006
Tissue response to polyglycolide, polydioxanone, polylevolactide, and metallic pins in cancellous bone: An experimental study on rabbits
Authors: Pihlajamäki Harri , Salminen Sari , Laitinen Outi , Tynninen Olli , Böstman Ole 
Published: June 2006

AbstractThe purpose of this study was to investigate, qualitatively and histoquantitatively, the tissue response of rabbit femur cancellous bone to polyglycolide (PGA), polydioxanone (PDS), polylevolactide (PLLA), and stainless steel pins under identical conditions. Eighty knees in 50 rabbits were operated on by inserting bioabsorbable pins (PGA, PDS, or PLLA) together with metallic Kirschner wire in 60, and two metallic Kirschner wires alone in 20 knees, while 20 knees served as intact controls. Follow‐up times were 3, 6, 12, 24, and 52 weeks. Cancellous bone tissue response to implants was studied using histological, histomorphometrical, microradiographical, and oxytetracycline fluorescence methods. Residual fragments of PGA and PDS were seen at 24 weeks. Complete degradation of these polymers had taken place before 52 weeks. No signs of degradation of the PLLA pins were observed within the entire follow‐up period. The osteoid formation surfaces at tissue implant‐interface were statistically larger in all test groups as compared to intact controls. The number of macrophages at tissue implant‐interfaces increased in all bioabsorbable implant specimens until 6 weeks, and with PGA until 12 weeks. No differences in the osseous response emerged when comparing groups of bioabsorbable implants with each other or with stainless steel group. Bioabsorbable pins and metallic Kirschner wires evoked an osteoconductive response in the cancellous bone surrounding implant, but the response intensity between implants displayed no differences. This suggests a simple, nonspecific walling‐off new‐bone front type of response. Consequently, the polymers possessed no specific osteostimulatory or osteoinhibitory properties. Within the follow‐up, no significant differences in biocompatibility between the implants appeared, and no frank inflammatory foreign‐body reactions occurred. The small‐volume pins obviously did not exceed the local tissue tolerance and clearing capacity of the bone. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:1597–1606, 2006
Distribution of Kv1‐like potassium channels in the electromotor and electrosensory systems of the weakly electric fish Apteronotus leptorhynchus
Authors: Smith G. Troy , Unguez Graciela A. , Weber Christopher M. 
Published: June 2006

AbstractThe electromotor and electrosensory systems of the weakly electric fish Apteronotus leptorhynchus are model systems for studying mechanisms of high‐frequency motor pattern generation and sensory processing. Voltage‐dependent ionic currents, including low‐threshold potassium currents, influence excitability of neurons in these circuits and thereby regulate motor output and sensory filtering. Although Kv1‐like potassium channels are likely to carry low‐threshold potassium currents in electromotor and electrosensory neurons, the distribution of Kv1 α subunits in A. leptorhynchus is unknown. In this study, we used immunohistochemistry with six different antibodies raised against specific mammalian Kv1 α subunits (Kv1.1–Kv1.6) to characterize the distribution of Kv1‐like channels in electromotor and electrosensory structures. Each Kv1 antibody labeled a distinct subset of neurons, fibers, and/or dendrites in electromotor and electrosensory nuclei. Kv1‐like immunoreactivity in the electrosensory lateral line lobe (ELL) and pacemaker nucleus are particularly relevant in light of previous studies suggesting that potassium currents carried by Kv1 channels regulate neuronal excitability in these regions. Immunoreactivity of pyramidal cells in the ELL with several Kv1 antibodies is consistent with Kv1 channels carrying low‐threshold outward currents that regulate spike waveform in these cells (Fernandez et al., J Neurosci 2005;25:363–371). Similarly, Kv1‐like immunoreactivity in the pacemaker nucleus is consistent with a role of Kv1 channels in spontaneous high‐frequency firing in pacemaker neurons. Robust Kv1‐like immunoreactivity in several other structures, including the dorsal torus semicircularis, tuberous electroreceptors, and the electric organ, indicates that Kv1 channels are broadly expressed and are likely to contribute significantly to generating the electric organ discharge and processing electrosensory inputs. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Assessing functional mobility in survivors of lower‐extremity sarcoma: Reliability and validity of a new assessment tool
Authors: Marchese Victoria G. , Rai Shesh N. , Carlson Claire A. , Hinds Pamela S. , Spearing Elena M. , Zhang Lijun , Callaway Lulie , Neel Michael D. , Rao Bhaskar N. , Ginsberg Jill P. 
Published: June 2006

AbstractBackgroundReliability and validity of a new tool, Functional Mobility Assessment (FMA), were examined in patients with lower‐extremity sarcoma. FMA requires the patients to physically perform the functional mobility measures, unlike patient self‐report or clinician administered measures.ProcedureA sample of 114 subjects participated, 20 healthy volunteers and 94 patients with lower‐extremity sarcoma after amputation, limb‐sparing, or rotationplasty surgery. Reliability of the FMA was examined by three raters testing 20 healthy volunteers and 23 subjects with lower‐extremity sarcoma. Concurrent validity was examined using data from 94 subjects with lower‐extremity sarcoma who completed the FMA, Musculoskeletal Tumor Society (MSTS), Short‐Form 36 (SF‐36v2), and Toronto Extremity Salvage Scale (TESS) scores. Construct validity was measured by the ability of the FMA to discriminate between subjects with and without functional mobility deficits.ResultsFMA demonstrated excellent reliability (ICC [2,1] ≥0.97). Moderate correlations were found between FMA and SF‐36v2 (r = 0.60, P < 0.01), FMA and MSTS (r = 0.68, P < 0.01), and FMA and TESS (r = 0.62, P < 0.01). The patients with lower‐extremity sarcoma scored lower on the FMA as compared to healthy controls (P < 0.01).ConclusionThe FMA is a reliable and valid functional outcome measure for patients with lower‐extremity sarcoma. This study supports the ability of the FMA to discriminate between patients with varying functional abilities and supports the need to include measures of objective functional mobility in examination of patients with lower‐extremity sarcoma. Pediatr Blood Cancer 2007;49:183–189. © 2006 Wiley‐Liss, Inc.
Macromolecular properties from light‐scattering experimental data using linear inverse problem theory
Authors: Virtuoso Luciano S. , Sebastião Rita C. O. , Braga João P. , Da Silva Luis H. M. 
Published: June 2006

AbstractThe inversion of the temporal correlation function in dynamic light‐scattering experimental data for polyethylene oxide + H2O + NaCl is treated in the present work. The relaxation time distribution function for this ill‐posed problem is obtained by a recurrent neural network, using analytical inverse Laplace transform as the initial condition. Diffusion coefficient and particle size distributions can also be retrieved from this relaxation time distribution, providing important information for the experimental researcher. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Rotor flux magnitude and angle control strategy for doubly fed induction generators
Authors: Anaya‐Lara Olimpo , Hughes F. Michael , Jenkins Nicholas , Strbac Goran 
Published: June 2006

AbstractA new control strategy is investigated for Doubly Fed Induction Generators (DFIGs). It exercises control over the generator terminal voltage and output power by adjusting the magnitude and angle of the rotor flux vector. It is shown that this control strategy leads to low interaction between the power and voltage control loop, better system damping and voltage recovery following faults, and it also provides enhanced frequency regulation capability compared with that achieved with existing DFIG controllers described in the open literature. The dynamic performance of the proposed DFIG control is tested for small and large disturbances using a generic network that combines wind and conventional synchronous generation. Simulation results are presented and discussed that demonstrate the capabilities of the new strategy to enhance DFIG performance and its contribution to network operation.