bluuebunny/crossref_metadata_2025_split huggingface dataset:
A critical reevaluation of the stationary axonal cytoskeleton hypothesis
Authors: Brown Anthony , Jung Peter 
Published: October 2012

AbstractNeurofilaments are transported along axons in a rapid intermittent and bidirectional manner but there is a long‐standing controversy about whether this applies to all axonal neurofilaments. Some have proposed that only a small proportion of axonal neurofilaments are mobile and that most are deposited into a persistently stationary and extensively cross‐linked cytoskeleton that remains fixed in place for many months without movement, turning over very slowly. In contrast, others have proposed that this hypothesis is based on a misinterpretation of the experimental data and that, in fact, all axonal neurofilaments move. These contrary perspectives have distinct implications for our understanding of how neurofilaments are organized and reorganized in axons both in health and disease. Here, we discuss the history and substance of this controversy. We show that the published data on the kinetics and distribution of neurofilaments along axons favor a simple “stop and go” transport model in which axons contain a single population of neurofilaments that all move in a stochastic, bidirectional and intermittent manner. Based on these considerations, we propose a dynamic view of the neuronal cytoskeleton in which all neurofilaments cycle repeatedly between moving and pausing states throughout their journey along the axon. The filaments move infrequently, but the average pause duration is on the order of hours rather than weeks or months. Against this fluid backdrop, the action of molecular motors on neurofilaments can have dramatic effects on neurofilament organization that would not be possible if the neurofilaments were extensively cross‐linked into a truly stationary network. © 2012 Wiley Periodicals, Inc
CD66c is a novel marker for colorectal cancer stem cell isolation, and its silencing halts tumor growth in vivo
Authors: Gemei Marica , Mirabelli Peppino , Di Noto Rosa , Corbo Claudia , Iaccarino Antonino , Zamboli Anna , Troncone Giancarlo , Galizia Gennaro , Lieto Eva , Del Vecchio Luigi , Salvatore Francesco 
Published: October 2012

AbstractBACKGROUND:Despite the well recognized expression of the cell surface markers cluster of differentiation 44 (homing cell adhesion molecule) and CD133 (Prominin 1) on human colorectal cancer stem cells (CCSCs), these molecules do not appear to be effective targets for stem cell‐directed therapies. Because the surface marker CD66c (also known as carcinoembryonic antigen‐related cell adhesion molecule 6) has demonstrated promise as a therapeutic target in pancreatic malignancy, the authors evaluated its potential as a target for stem cell‐directed treatment of colorectal cancer.METHODS:First, the authors characterized CD66c expression by flow cytometry and immunohistochemistry in colon cancer samples and in normal colon tissues. Then, the coexpression of CD66c and CD133 was evaluated on putative CCSCs. CD66c expression also was measured in stem cell‐enriched colon spheres. Finally, the effects of small‐interfering RNA‐mediated CD66c silencing on the in vitro and in vivo growth of Caco2 colon cancer cells were evaluated.RESULTS:CD66c expression was significantly higher in colon cancers than in contiguous normal colon tissues and paralleled cancer stage. CD66c was absent in CD133‐positive cells that were isolated from normal colon, whereas its expression was brightest (CD66cbright) in CD133‐positive cells from colon cancer samples. In vitro experiments demonstrated that colon spheres were considerably enriched in a CD66cbright population in a fashion comparable to the enrichment observed in fresh liver metastases. In vitro proliferation and clonogenic potential were hampered when CD66c was silenced in Caco2 cells. Finally, in vivo xenograft experiments demonstrated that CD66c silencing almost completely abrogated the tumorigenic potential of Caco2 cells.CONCLUSIONS:CD66cbright expression was associated with colon cancer stem cells and CD66c silencing blocked tumor growth, thereby opening the way to a potential new treatment for colon cancer. Cancer 2013. © 2012 American Cancer Society.
Patient‐specific finite element analysis of carotid artery stenting: a focus on vessel modeling
Authors: Auricchio F. , Conti M. , Ferrara A. , Morganti S. , Reali A. 
Published: October 2012

SUMMARYFinite element analysis is nowadays a well‐assessed technique to investigate the impact of stenting on vessel wall and, given the rapid progression of both medical imaging techniques and computational methods, the challenge of using the simulation of carotid artery stenting as procedure planning tool to support the clinical practice can be approached. Within this context, the present study investigates the impact of carotid stent apposition on carotid artery anatomy by means of patient‐specific finite element analysis. In particular, we focus on the influence of the vessel constitutive model on the prediction of carotid artery wall tensional state of lumen gain and of vessel straightening. For this purpose, we consider, for a given stent design and CA anatomy, two constitutive models for the CA wall, that is, a hyperelastic isotropic versus a fiber‐reinforced hyperelastic anisotropic model. Despite both models producing similar patterns with respect to stress distribution, the anisotropic model predicts a higher vessel straightening and a more evident discontinuity of the lumen area near the stent ends as observed in the clinical practice. Although still affected by several simplifications, the present study can be considered as further step toward a realistic simulation of carotid artery stenting.Copyright © 2012 John Wiley & Sons, Ltd.
Evaluation of FMH QuikQuant for the detection and quantification of fetomaternal hemorrhage
Authors: Pastoret Cedric , Priol Jerome Le , Fest Thierry , Roussel Mikael 
Published: October 2012

AbstractBackground:The Kleihauer–Betke test (KBT) is the most widely used assay for fetomaternal hemorrhage (FMH) detection in rhesus D negative women. In the current study, we sought to evaluate the performance of a flow cytometry (FCM) kit (FMH QuikQuant) using an anti‐HbF antibody.Methods:Eighty‐three pregnant women, 58 umbilical cord blood (UCB) dilutions in adult blood, and 6 control samples were tested in parallel with FCM and KBT.Results:Firstly, we compared for each assay, on the 58 UCB preparations, results obtained to dilutions prepared. FCM results showed an excellent correlation (r = 0.97), a high reproducibility with a coefficient of variation lower than 20% for values reaching 10 fetal RBCs. KBT values were correlated (r = 0.94) but exhibited a poor reproducibility. Then, we compared both techniques on all samples. FCM showed a good correlation with KBT (r = 0.87) but the KBT exhibited a systematic overestimation of the FMH. For 8 out of 83 pregnant women, KBT was positive. Five were concordant with FCM results (KBT+/FCM+). On the three discordant (KBT+/FCM−), 2 were finally classified as false positive of the KBT because a second control sample was negative and additionally, FCM identified an increased rate of F cells. One discordant case (KBT+/FCM−) remained unexplained. By receiver operating characteristic analysis, we found a threshold at 4.5 RBCs for FCM with a sensitivity of 89.8% and a specificity of 93.2%.Conclusions:The FMH QuikQuant kit is a reliable and highly reproductive FCM method for FMH quantification. © 2012 International Clinical Cytometry Society
Digital rights management system with user privacy, usage transparency, and superdistribution support
Authors: Yen Chih‐Ta , Liaw Horng‐Twu , Lo Nai‐Wei 
Published: October 2012

SUMMARYIn the modern world, digital content has been massively produced, distributed, and consumed by human beings; consequently, how to protect the rights and benefits of content consumers, producers, and distributors has become a crucial issue. One promising solution is to design a full‐fledged digital rights management (DRM) system. In this study we introduce a new design on the digital rights management system providing user privacy, usage transparency, and superdistribution. A comprehensive set of DRM processing functions and corresponding mechanisms are developed in our system to support various business process requirements. Superdistribution support is embedded in our system design. A prototype is implemented to verify our system design. To protect consumer privacy, a temporary identity is generated for each consumer using the KryptoKnight protocol. Elliptic curve cryptography‐based encryption scheme is adopted for messages transmitted among servers and client over an unsecure communication channel. For usage transparency, a user‐friendly DRM client package (software) is introduced in the proposed DRM system to achieve content protection and support user convenience in usage.Copyright © 2012 John Wiley & Sons, Ltd.
Protocol design and data detection for two‐way relay networks with fractional asynchronous delays
Authors: Fang Zhaoxi , Liang Feng , Zhang Shaozhong , Shi Jiong 
Published: October 2012

SUMMARYIn wireless two‐way relay systems, it is difficult to achieve perfect timing synchronization among different nodes. In this paper, we investigate relaying protocol design and data detect schemes for asynchronous two‐way relaying systems to combat the intersymbol interference caused by asynchronous transmission. We consider fractional asynchronous delays and two schemes are proposed based on cyclic prefixed single carrier block transmission, namely, the receiver frequency domain equalization scheme and relay synchronization and network coding (RSNC) scheme. In the receiver frequency domain equalization scheme, the relay simply amplifies the received signal and forwards to the two source nodes, and fractionally spaced frequency domain equalizer (FS‐FDE) is employed at the receiver to recover the transmit data. In the RSNC scheme, the asynchronous signals are resynchronized with an FS‐FDE at the relay node. The output signals of FS‐FDE are then demodulated and network coded before forwarding to the two source nodes. In this RSNC scheme, data detection at the source nodes is the same as that in synchronous networks because the asynchronous signals have already been synchronized at the relay node. Simulation results show that the performance of both schemes is almost the same as in the perfect synchronized two‐way relaying systems. Copyright © 2012 John Wiley & Sons, Ltd.
Functional redundancy between Cdc14 phosphatases in zebrafish ciliogenesis
Authors: Clément Aurélie , Solnica‐Krezel Lilianna , Gould Kathleen L. 
Published: October 2012

AbstractBackground: Cyclin‐dependent kinases (Cdks) and their counteracting phosphatases are key regulators of cell cycle progression. In yeasts, the Cdc14 family of phosphatases promotes exit from mitosis and progression through cytokinesis by reversing phosphorylation of Cdk1 substrates. In vertebrates, CDC14 paralogs, CDC14A and CDC14B, have so far been implicated in processes ranging from DNA damage repair, meiosis, centrosome duplication to ciliogenesis. However, the question of whether CDC14 paralogs can functionally compensate for each other has yet to be addressed. Results: Here, using antisense morpholino oligonucleotides to inhibit Cdc14A1 function, we observed that Cdc14A1 depleted zebrafish embryos displayed ventrally curved body and left‐right asymmetry defects, similar to Cdc14B deficient embryos and zebrafish mutants with cilia defects. Accordingly, we found that Cdc14A1, like Cdc14B, plays a role in ciliogenesis in the Kupffer's vesicle (KV) and other ciliated tissues, and can do so independently of its function in cell cycle. Furthermore, we observed reciprocal suppression of KV cilia length defects of Cdc14A1 and Cdc14B deficient embryos by cdc14b and cdc14a1 RNAs, respectively. Conclusions: Together, these studies demonstrate for the first time that Cdc14A and Cdc14B have overlapping functions in the ciliogenesis process during zebrafish development. Developmental Dynamics, 2012. © 2012 Wiley Periodicals, Inc.
Genomic variation in cline shape across a hybrid zone
Authors: Kingston Sarah E. , Jernigan Robert W. , Fagan William F. , Braun David , Braun Michael J. 
Published: October 2012

AbstractHybrid zones are unique biological interfaces that reveal both population level and species level evolutionary processes. A genome‐scale approach to assess gene flow across hybrid zones is vital, and now possible. In Mexican towhees (genus Pipilo), several morphological hybrid gradients exist. We completed a genome survey across one such gradient (9 populations, 140 birds) using mitochondrial DNA, 28 isozyme, and 377 AFLP markers. To assess variation in introgression among loci, cline parameters (i.e., width, center) for the 61 clinally varying loci were estimated and compiled into genomic distributions for tests against three empirical models spanning the range of observed cline shape. No single model accounts for observed variation in cline shape among loci. Numerous backcross individuals near the gradient center confirm a hybrid origin for these populations, contrary to a previous hypothesis based on social mimicry and character displacement. In addition, the observed variation does not bin into well‐defined categories of locus types (e.g., neutral vs. highly selected). Our multi‐locus analysis reveals cross‐genomic variation in selective constraints on gene flow and locus‐specific flexibility in the permeability of the interspecies membrane.
Fine‐scale selection by ovipositing females increases egg survival
Authors: Gall Brian G. , Brodie Edmund D. , Brodie Edmund D. 
Published: October 2012

AbstractOne of the most important defenses for the eggs of ovipositing female organisms is to avoid being laid in the same habitat as their predators. However, for most organisms, completely avoiding an offspring's predators is not possible. One mechanism that has been largely overlooked is for females to partition an oviposition site into microhabitats that differ in quality for offspring survival. We conducted a series of experiments to examine whether female newts avoid microhabitats utilized by their offspring's primary predator, caddisfly larvae. Female newts avoided laying eggs near predatory caddisflies and shifted egg laying upward in the water column when provided with a vertical dimension. Caddisflies were attracted to chemical stimuli from female newts and their eggs, yet primarily used benthic areas in experimental chambers. Finally, results from a field experiment indicate that the behavioral strategy employed by female newts increases offspring survival. This subset of non‐genetic maternal effects, micro‐oviposition avoidance, is likely an important yet underexplored mechanism by which females increase offspring survival.
Photocatalytic TiO2 Macroscopic Fibers Obtained Through Integrative Chemistry
Authors: Kinadjian Natacha , Le Bechec Mickael , Pigot Thierry , Dufour Fabien , Durupthy Olivier , Bentaleb Ahmed , Prouzet Eric , Lacombe Sylvie , Backov Rénal 
Published: October 2012

AbstractThe photocatalytic properties of titanium dioxide depend not only on its electronic properties, but also on the material size and shape, which can increase interactions between the reactants and catalyst. Most studies to date show that reducing the particle size down to the nanoscale increases photocatalytic efficiency, as a result of a higher surface to volume ratio and because a larger proportion of the material is actually irradiated by light. We demonstrate that a multiscale shape design, which integrates surface roughness, particle shape, and 1D material processing and orientation, can favor photocatalytic properties in the solid–gas regime, especially mineralization (conversion into CO2), when the hierarchical 1D orientation of the material is combined with unidirectional gas flow. Several materials with hierarchical structure were prepared and characterized. They have been tested for the photocatalytic mineralization of gaseous acetone and compared with commercial catalysts. Our study reveals that a suitable combination of multiscale design and optimization of the material orientation and gas flow favors high mineralization.
Competing Symmetry Breaking and Spin Crossover in [FeH2L2–Me](ClO4)2
Authors: Watanabe Hiroshi , Bréfuel Nicolas , Collet Eric , Toupet Loïc , Tanaka Koichiro , Tuchagues Jean‐Pierre 
Published: October 2012

AbstractIn this contribution, we describe the symmetry breaking that appears in the low‐spin phase of the spin crossover (SC) complex [FeH2L2–Me](ClO4)2, [H2L2–Me = Bis{[(2‐methylimidazol‐4‐yl)methylidene]‐3‐aminopropyl}ethylenediamine], for which low‐spin (LS) to high‐spin (HS) transition may be thermally activated or photoinduced. In the LS phase stable at low temperature, a symmetry breaking occurs at around 120 K, while in the photoinduced HS (PIHS) state the high symmetry is recovered. The relaxation from this PIHS state to the LS low‐symmetry phase occurs through an intermediate LS high‐symmetry phase. The sequence of phases was evidenced by using magnetic susceptibility, X‐ray diffraction, and infrared spectroscopy data.
Early assessment of acute coronary syndromes in the emergency department: the potential diagnostic value of circulating microRNAs
Authors: Oerlemans Martinus I. F. J. , Mosterd Arend , Dekker Marieke S. , de Vrey Evelyn A. , van Mil Alain , Pasterkamp Gerard , Doevendans Pieter A. , Hoes Arno W. , Sluijter Joost P. G. 
Published: October 2012

AbstractPrevious studies investigating the role of circulating microRNAs in acute coronary syndrome (ACS) were based on small patient numbers, performed no comparison with established markers of cardiac injury and did not have appropriate controls. We determined the potential diagnostic value of circulating microRNAs as novel early biomarkers in 332 suspected ACS patients on presentation to the emergency department (ED) in a prospective single‐centre study including cardiac miRNAs (miR‐1, ‐208a and ‐499), miR‐21 and miR‐146a. Levels of all miRs studied were significantly increased in 106 patients diagnosed with ACS, even in patients with initially negative high‐sensitive (hs) troponin or symptom onset <3 h. MiR‐1, miR‐499 and miR‐21 significantly increased the diagnostic value in all suspected ACS patients when added to hs‐troponin T (AUC 0.90). These three miRs were strong predictors of ACS independent of clinical co‐variates including patient history and cardiovascular risk factors. Interestingly, the combination of these three miRs resulted in a significantly higher AUC of 0.94 than hs‐troponin T (0.89). Circulating microRNAs hold great potential as novel early biomarkers for the management of suspected ACS patients.
Quantifying effects of deep and near‐surface chemical erosion on cosmogenic nuclides in soils, saprolite, and sediment
Authors: Riebe Clifford S. , Granger Darryl E. 
Published: October 2012

ABSTRACTCosmogenic nuclides in rock, soil, and sediment are routinely used to measure denudation rates of catchments and hillslopes. Although it has been shown that these measurements are prone to biases due to chemical erosion in regolith, most studies of cosmogenic nuclides have ignored this potential source of error. Here we quantify the extent to which overlooking effects of chemical erosion introduces bias in interpreting denudation rates from cosmogenic nuclides. We consider two end‐member effects: one due to weathering near the surface and the other due to weathering at depth. Near the surface, chemical erosion influences nuclide concentrations in host minerals by enriching (or depleting) them relative to other more (or less) soluble minerals. This increases (or decreases) their residence times relative to the regolith as a whole. At depth, where minerals are shielded from cosmic radiation, chemical erosion causes denudation without influencing cosmogenic nuclide buildup. If this effect is ignored, denudation rates inferred from cosmogenic nuclides will be too low. We derive a general expression, termed the ‘chemical erosion factor’, or CEF, which corrects for biases introduced by both deep and near‐surface chemical erosion in regolith. The CEF differs from the ‘quartz enrichment factor’ of previous work in that it can also be applied to relatively soluble minerals, such as olivine. Using data from diverse climatic settings, we calculate CEFs ranging from 1.03 to 1.87 for cosmogenic nuclides in quartz. This implies that ignoring chemical erosion can lead to errors of close to 100% in intensely weathered regolith. CEF is strongly correlated with mean annual precipitation across our sites, reflecting climatic influence on chemical weathering. Our results indicate that quantifying CEFs is crucial in cosmogenic nuclide studies of landscapes where chemical erosion accounts for a significant fraction of the overall denudation. Copyright © 2012 John Wiley & Sons, Ltd.
Control of hydrothermal waves in a thermocapillary flow using a gradient‐based control strategy
Authors: Muldoon Frank 
Published: October 2012

SUMMARYThe problem of controlling the hydrothermal waves in a thermocapillary flow is addressed using a gradient‐based control strategy. The state equations are the two‐dimensional unsteady incompressible Navier–Stokes and energy equations under the Boussinesq approximation. The modeled problem is the ‘open boat’ process of crystal growth, the flow which is driven by Marangoni and buoyancy effects. The control is a spatially and temporally varying heat flux boundary condition at the free surface. The control that minimizes the hydrothermal waves is found using a conjugate gradient method, where the gradient of the objective function with respect to the control variables is obtained from solving a set of adjoint equations. The effectiveness of choices of the parameters governing the control algorithm is examined. Almost complete suppression of the hydrothermal waves is obtained for certain choices of the parameters governing the control algorithm. The numerical issues involved with finding the control using the optimizer are discussed, and the features of the resulting control are analyzed with the goal of understanding how it affects the flow.Copyright © 2012 John Wiley & Sons, Ltd.