bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling of porous scaffold deformation induced by medium perfusion
Authors: Podichetty Jagdeep T. , Madihally Sundararajan V.
Published: November 2013

In this study, we tested the possibility of calculating permeability of porous scaffolds utilized in soft tissue engineering using pore size and shape. We validated the results using experimental measured pressure drop and simulations with the inclusion of structural deformation. We prepared Polycaprolactone (PCL) and Chitosan–Gelatin (CG) scaffolds by salt leaching and freeze drying technique, respectively. Micrographs were assessed for pore characteristics and mechanical properties. Porosity for both scaffolds was nearly same but the permeability varied 10‐fold. Elastic moduli were 600 and 9 kPa for PCL and CG scaffolds, respectively, while Poisson's ratio was 0.3 for PCL scaffolds and ∼1.0 for CG scaffolds. A flow‐through bioreactor accommodating a 10 cm diameter and 0.2 cm thick scaffold was used to determine the pressure‐drop at various flow rates. Additionally, computational fluid dynamic (CFD) simulations were performed by coupling fluid flow, described by Brinkman equation, with structural mechanics using a dynamic mesh. The experimentally obtained pressure drop matched the simulation results of PCL scaffolds. Simulations were extended to a broad range of permeabilities (10−10 m2 to 10−14 m2), elastic moduli (10–100,000 kPa) and Poisson's ratio (0.1–0.49). The results showed significant deviation in pressure drop due to scaffold deformation compared to rigid scaffold at permeabilities near healthy tissues. Also, considering the scaffold as a nonrigid structure altered the shear stress profile. In summary, scaffold permeability can be calculated using scaffold pore characteristics and deformation could be predicted using CFD simulation. These relationships could potentially be used in monitoring tissue regeneration noninvasively via pressure drop. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 737–748, 2014.
Complete subchondral bone defect regeneration with a tricalcium phosphate collagen implant and osteoinductive growth factors: A randomized controlled study in Göttingen minipigs
Authors: Gotterbarm Tobias , Breusch Steffen J. , Jung Martin , Streich Nikolaus , Wiltfang Jörg , Berardi Vilei Simona , Richter Wiltrud , Nitsche Tobias
Published: November 2013

The restoration and reconstruction of osseous defects close to the joint, constitutes a challenging field for reconstructive surgery. A dual‐layer implant of β‐tricalcium phosphate (TCP) and a collagens I/III scaffold was evaluated in a prospective, randomized comparison in a larger animal model. For this purpose, a standardized osteochondral defect was created in the medial facet of the patellar groove in both stifle joints of Göttingen minipigs. Critical‐size osseous defects were either left empty (spontaneous healing; group 1; n = 12) or treated with the two‐layer TCP collagen implant (group 2; n = 12). In group 3 (n = 12), additional growth factor mixture (GFM) was supplemented (bone morphogenetic proteins 2, 3, 4, 6, 7, and TGF‐β1, 2, 3). Osseous defect regeneration was assessed at 6, 12, and 52 weeks postoperatively (n = 4). Qualitative and quantitative histomorphometric assessment of defect regeneration and bone substitute resorption was conducted by means of light microscopy, fluorescence microscopy, and microradiography. Critical‐size defects did not heal spontaneously throughout follow‐up (group 1: max. 21.84 ± 2.81% defect area at 52 weeks). The TCP layer of the implant significantly increased the amount of new bone formation with 29.8 ± 9.68% at 6 weeks and 40.09 ± 4.76% at 12 weeks when compared with controls. After 52 weeks, the TCP was almost fully degraded (4.35 ± 3.70%) and the defect was restored with lamellar trabecular bone (31.28 ± 5.02%). Growth factor supplementation resulted in earlier resorption of the TCP implant and faster defect regeneration. The dual‐layer TCP collagen implant is suitable to restore subchondral osseous defects. Additional use of GFM increased the resorption of the TCP layer, but did not foster new bone formation. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 933–942, 2014.
DBU‐catalyzed Multicomponent Synthesis: Facile Access of 4,5,6,9‐Tetrahydro‐pyrido[3,2‐c]quinolines
Authors: Chaniyara Ravi , Thakrar Shailesh , Kakadiya Rajesh , Marvania Bhavin , Detroja Dilip , Vekariya Nikhil , Upadhyay Kuldip , Manvar Atul , Shah Anamik
Published: November 2013

An efficient synthesis of 4H,5H,6H,9H‐pyrido[ij]pyrano[3,2‐c]quinolines 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n, 4o, 4p, 4q, 4r, 4s, 4t as well as spiro compound 6 was achieved via multicomponent approach by using DBU as a nucleophilic catalyst under the remarkably mild reaction conditions. The structures of the compounds were characterized by 1H NMR, 13C NMR, and mass spectral analysis. An attractive feature of this inexpensive protocol includes facile synthesis, shorter reaction time, ease of work‐up, large number of functional group tolerance, and good to excellent yields with high purity.
Diversity of ionizing radiation‐resistant bacteria obtained from the Taklimakan Desert
Authors: Yu Li Zhi‐Han , Luo Xue‐Song , Liu Ming , Huang Qiaoyun
Published: November 2013

So far, little is known about the diversity of the radiation‐resistant microbes of the hyperarid Taklimakan Desert. In this study, ionizing radiation (IR)‐resistant bacteria from two sites in Xinjiang were investigated. After exposing the arid (water content of 0.8 ± 0.3%) and non‐arid (water content of 21.3 ± 0.9%) sediment samples to IR of 3000 Gy using a 60Co source, a total of 52 γ‐radiation‐resistant bacteria were isolated from the desert sample. The 16S rRNA genes of all isolates were sequenced. The phylogenetic tree places these isolates into five groups: Cytophaga–Flavobacterium–Bacteroides, Proteobacteria, Deinococcus‐Thermus, Firmicutes, and Actinobacteria. Interestingly, this is the first report of radiation‐resistant bacteria belonging to the genera Knoellia, Lysobacter, Nocardioides, Paracoccus, Pontibacter, Rufibacter and Microvirga. The 16s rRNA genes of four isolates showed low sequence similarities to those of the published species. Phenotypic analysis showed that all bacteria in this study are able to produce catalase, suggesting that these bacteria possess reactive oxygen species (ROS)‐scavenging enzymes. These radiation‐resistant bacteria also displayed diverse metabolic properties. Moreover, their radiation resistances were found to differ. The diversity of the radiation‐resistant bacteria in the desert provides further ecological support for the hypothesis that the ionizing‐radiation resistance phenotype is a consequence of the evolution of ROS‐scavenging systems that protect cells against oxidative damage caused by desiccation.
Identification of functional residues essential for dehalogenation by the non‐stereospecific α‐haloalkanoic acid dehalogenase from Rhizobium sp. RC1
Authors: Hamid Azzmer Azzar Abdul , Tengku Abdul Hamid Tengku Haziyamin , Wahab Roswanira Abdul , Huyop Fahrul
Published: November 2013

The non‐stereospecific α‐haloalkanoic acid dehalogenase DehE from Rhizobium sp. RC1 catalyzes the removal of the halide from α‐haloalkanoic acid D,L‐stereoisomers and, by doing so, converts them into hydroxyalkanoic acid L,D‐stereoisomers, respectively. DehE has been extensively studied to determine its potential to act as a bioremediation agent, but its structure/function relationship has not been characterized. For this study, we explored the functional relevance of several putative active‐site amino acids by site‐specific mutagenesis. Ten active‐site residues were mutated individually, and the dehalogenase activity of each of the 10 resulting mutants in soluble cell lysates against D‐ and L‐2‐chloropropionic acid was assessed. Interestingly, the mutants W34 → A, F37 → A, and S188 → A had diminished activity, suggesting that these residues are functionally relevant. Notably, the D189 → N mutant had no activity, which strongly implies that it is a catalytically important residue. Given our data, we propose a dehalogenation mechanism for DehE, which is the same as that suggested for other non‐stereospecific α‐haloalkanoic acid dehalogenases. To the best of our knowledge, this is the first report detailing a functional aspect for DehE, and our results could help pave the way for the bioengineering of haloalkanoic acid dehalogenases with improved catalytic properties.
HERAS: A helium jet to prevent damage on works of art in Raman experiments
Authors: Ruvalcaba‐Sil José Luis , Casanova‐González Edgar , Pérez‐Castellanos Nora Ariadna , García‐Bucio María Angélica
Published: November 2013

Raman spectroscopy is often used for non‐destructive analysis of works of art, polymers and biological materials, but in some cases, the laser beam can cause damages on the surface being studied due to the deposited beam energy. When possible, such damage can be prevented by minimizing laser intensity or acquisition time, but this is usually available only on high sensitivity bench‐top spectrometers. Portable Raman spectrometers are commonly not so flexible and an alternative is needed to ensure the safe study of sensitive works of art and other fragile materials. A helium jet aimed directly at the laser spot may prevent this damage from occurring and, in some cases, helps improving the Raman spectra. We designed a simple system (HERAS, Helium Raman System) consisting of a pinhole collimator, coupled to a helium line and a gas mass flux control and tested it on pyroxylin, vermilion and ochre paint references and pigment samples, using a 785 nm portable Raman spectrometer at various laser powers. Experimental conditions slightly differ for each sample, but small burns on the surface were avoided in all cases and only some ablation was observed on the most sensitive materials. The use of this coupled system allows the non‐destructive application of Raman to a wider variety of materials, while the technique remains portable. This setup may be used in bench‐top apparatus as well. Copyright © 2013 John Wiley & Sons, Ltd.
Ultrasensitive RDX detection with commercial SERS substrates
Authors: Almaviva S. , Botti S. , Cantarini L. , Fantoni R. , Lecci S. , Palucci A. , Puiu A. , Rufoloni A.
Published: November 2013

Surface‐enhanced Raman spectroscopy (SERS) measurements on 1,3,5‐trinitroperhydro‐1,3,5‐triazine were performed with a table‐top micro‐Raman system exciting the analyte with a diode laser emitting at 785 nm. The main Raman features of 1,3,5‐trinitroperhydro‐1,3,5‐triazine were clearly identified, and a careful optimization of acquisition parameters was performed in order to increase the overall sensitivity of the apparatus. The amount of the sampled substance was determined through the analysis of high‐resolution scanning electron microscope images of the substrate covered with the residual explosive and resulted to be of the order of few tens of picograms. This value demonstrates the applicability of commercial substrates to the ultrasensitive surface‐enhanced Raman spectroscopy detection of explosives, allowing for their identification in real time. Copyright © 2013 John Wiley & Sons, Ltd.
A Genetic Algorithm‐Based Method for the Automatic Reduction of Reaction Mechanisms
Authors: Sikalo N. , Hasemann O. , Schulz C. , Kempf A. , Wlokas I.
Published: November 2013

An automatic method for the reduction of chemical kinetic mechanisms under specific physical or thermodynamic conditions is presented. The method relies on the genetic algorithm search logic to gradually reduce the number of reactions from the detailed mechanism while still preserving its ability to describe the overall chemistry at an acceptable error. Accuracy of the reduced mechanism is determined by comparing its solution to the solution obtained with the full mechanism under the same initial and/or physical conditions. However, not only the chemical accuracy and the size of the mechanism are considered but also the time for its solution which helps to avoid stiff and slow converging mechanisms, thus preferring the fast solutions. The reduction method is demonstrated for a detailed mechanism for methane combustion, GRI‐Mech 3.0, which was reduced from 325 reactions and 53 species to 58 reactions and 26 species, and for an iron oxide formation mechanism from iron pentacarbonyl doped flames by Wlokas et al. (Int J Chem Kinet 2013, 45(8), 487–498),  originally consisting of 144 reactions and 34 species, which was reduced to 37 reactions and 24 species. The performance of the reduced mechanisms is shown for homogeneous constant pressure reactors and for burner‐stabilized flames. The results show a good agreement between reduced and full mechanisms for both the reactor and flame cases. The presented method is flexible and can be easily adjusted to either yield more accurate (but bigger) or smaller (but less accurate) reduced mechanisms, depending on the user's preference.
Norm‐controlled inversion in smooth Banach algebras, II
Authors: Gröchenig Karlheinz , Klotz Andreas
Published: November 2013

We show that smoothness implies norm‐controlled inversion: the smoothness of an element a in a Banach algebra with a one‐parameter automorphism group is preserved under inversion, and the norm of the inverse is controlled by the smoothness of a and by spectral data. In our context smooth subalgebras are obtained with the classical constructions of approximation theory and resemble spaces of differentiable functions, Besov spaces or Bessel potential spaces. To treat ultra‐smoothness, we resort to Dales‐Davie algebras. Furthermore, based on Baskakov's work, we derive explicit norm control estimates for infinite matrices with polynomial off‐diagonal decay. This is a quantitative version of Jaffard's theorem.
Cluster TOF‐SIMS imaging as a tool for micrometric histology of lipids in tissue
Authors: Bich Claudia , Touboul David , Brunelle Alain
Published: November 2013

Recent developments in instrumentation, ion beams or analyzers, for cluster time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) imaging are described here. The methods which are employed to increase the sensitivity or to perform three‐dimensional analyses in the organic materials are also illustrated. This review shows the improvements made for lipid imaging by cluster TOF‐SIMS in various types of material and applications, and gives reasons for the expansion of its utilization. © 2013 Wiley Periodicals, Inc. Mass Spec Rev 33: 442–451, 2014.
Hadamard slice encoding for reduced‐FOV diffusion‐weighted imaging
Authors: Saritas Emine Ulku , Lee Daeho , Çukur Tolga , Shankaranarayanan Ajit , Nishimura Dwight G.
Published: November 2013

Purpose

To improve the clinical utility of diffusion‐weighted imaging (DWI) by extending the slice coverage of a high‐resolution reduced field‐of‐view technique.

Theory

Challenges in achieving high spatial resolution restrict the use of DWI in assessment of small structures such as the spinal cord. A reduced field‐of‐view method with 2D echo‐planar radiofrequency (RF) excitation was recently proposed for high‐resolution DWI. Here, a Hadamard slice‐encoding scheme is proposed to double the slice coverage by exploiting the periodicity of the 2D echo‐planar RF excitation profile.

Methods

A 2D echo‐planar RF pulse and matching multiband refocusing RF pulses were designed using the Shinnar‐Le Roux algorithm to reduce band interference, and variable‐rate selective excitation to shorten the pulse durations. Hadamard‐encoded images were resolved through a phase‐preserving image reconstruction. The performance of the method was evaluated via simulations, phantom experiments, and in vivo high‐resolution axial DWI of spinal cord.

Results

The proposed scheme successfully extends the slice coverage, while preserving the sharp excitation profile and the reliable fat suppression of the original method. For in vivo axial DWI of the spinal cord, an in‐plane resolution of 0.7 × 0.7 mm2 was achieved with 16 slices.

Conclusion

The proposed Hadamard slice‐encoding scheme doubles the slice coverage of the 2D echo‐planar RF reduced field‐of‐view method without any scan‐time penalty. Magn Reson Med 72:1277–1290, 2014. © 2013 Wiley Periodicals, Inc.
User‐centric context data collection and provision harnessing Content‐Centric Networking paradigm
Authors: Seo Sin‐seok , Kang Joon‐Myung , Leon‐Garcia Alberto , Han Yoonseon , Won‐Ki Hong James
Published: November 2013

A comprehensive context management approach is necessary in the era of ubiquitous technologies, and efficient context data collection is one of the most fundamental and important processes for realizing comprehensive context management. Traditional context data collection approaches are based on Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) over Internet Protocol (IP), which has several disadvantages, such as lack of efficient mobility support, security and data transfer efficiency. Content‐Centric Networking (CCN), on the other hand, provides advantages in terms of mobility, security and bandwidth efficiency in comparison with IP. In this paper, we introduce our user‐centric comprehensive context management framework, and propose a secure and efficient context data collection and provision approach based on the framework using CCN as a network and transport layer. This context collection approach provides a flexible security mechanism by introducing three levels of security type. It also provides bandwidth efficiency by taking advantage of CCN's content caching; performance evaluation results show that our approach can reduce bandwidth consumption up to 99% for pull and up to 46% for push in comparison to a UDP/IP‐based system. Our approach also provides advantages in supporting mobility and leveraging multiple interfaces. Copyright © 2013 John Wiley & Sons, Ltd.
Field trial of a putative research algorithm for diagnosing ICD‐11 personality disorders in psychiatric patients: 1. Severity of personality disturbance
Authors: Kim Youl‐Ri , Blashfield Roger , Tyrer Peter , Hwang Soon‐Taeg , Lee Hong‐Seock
Published: November 2013

This preliminary field trial examines the reliability and validity of a proposed research algorithm for diagnosing International Classification of Diseases (ICD)‐11 personality disorders and its association with other psychiatric assessments for the primary classification of a single dimension of the five severity levels of personality dysfunction. In total, 137 psychiatric patients (119 with personality disorders and 18 without personality disorders) in Korea were assessed. In the first part of the study, inter‐rater reliability was evaluated with an independent assessment of personality (personality assessment schedule). In the second part of the study, (1) the algorithm that identified any personality disturbance was compared with the ICD‐10 and DSM‐IV personality disorder diagnostic equivalents, and (ii) the four levels of severity were examined for their associations with clinical pathology and social functioning. The results showed good agreement between the algorithm and the test instruments for identifying a personality disorder. A graded increase in clinical pathology and social dysfunction was observed with increasing severity of personality disorder. These findings suggest that a simple algorithm for recording severity of a personality disturbance had both construct validity and was useful in practice, which supports severity classification as a valuable concept. These findings need to be confirmed in other cultures and ethnic groups. Copyright © 2013 John Wiley & Sons, Ltd.
Plasmonic protection of the hot‐electron energy
Authors: Kempa Krzysztof
Published: November 2013

In the Letter by K. Kempa, the definitions of two auxiliary constants in Eqs. (10) and (11) were incorrectly given by the author. He now wishes to correct these equations. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Adaptive inverse control for parametric strict feedback systems with unknown failures of hysteretic actuators
Authors: Cai Jianping , Wen Changyun , Su Hongye
Published: November 2013

An adaptive compensation control scheme is proposed by using backstepping techniques for a class of uncertain nonlinear systems preceded by m hysteretic actuators, which exhibit unknown backlash nonlinearity and possibly experience unknown failures. An estimated smooth inverse of the actuator backlash is utilized in the controller design to compensate for the effects of the backlash and actuator failures. It is shown that the designed controllers can ensure all signals of closed‐loop system bounded for any failure pattern of hysteretic actuators and tracking performance is also maintained. Simulation studies confirm the effectiveness of the proposed controller, especially the improvement of system performances. Copyright © 2013 John Wiley & Sons, Ltd.
A data‐centric framework for debugging highly parallel applications
Authors: Dinh Minh Ngoc , Abramson David , Jin Chao , Gontarek Andrew , Moench Bob , DeRose Luiz
Published: November 2013

Contemporary parallel debuggers allow users to control more than one processing thread while supporting the same examination and visualisation operations of that of sequential debuggers. This approach restricts the use of parallel debuggers when it comes to large scale scientific applications run across hundreds of thousands compute cores. First, manually observing the runtime data to detect error becomes impractical because the data is too big. Second, performing expensive but useful debugging operations becomes infeasible as the computational codes become more complex, involving larger data structures, and as the machines become larger. This study explores the idea of a data‐centric debugging approach, which could be used to make parallel debuggers more powerful. It discusses the use of ad hoc debug‐time assertions that allow a user to reason about the state of a parallel computation. These assertions support the verification and validation of program state at runtime as a whole rather than focusing on that of only a single process state. Furthermore, the debugger's performance can be improved by exploiting the underlying parallel platform because the available compute cores can execute parallel debugging functions, while a program is idling at a breakpoint. We demonstrate the system with several case studies and evaluate the performance of the tool on a 20 000 cores Cray XE6. Copyright © 2013 John Wiley & Sons, Ltd.
A Theoretical Agent‐Based Model to simulate an Artificial Social Evolution
Authors: Nemiche Mohamed , M'Hamdi Ahmed , Chakraoui Mohamed , Cavero Vicent , Pla Lopez Rafael
Published: November 2013

Agent‐based social simulation as a computational approach to social simulation has been largely used to explore social phenomena. The purpose of this paper is to build a theoretical agent‐based model to simulate the social evolution of a set of agents/artificial societies. In this model, each agent (artificial society) has an available number of social behaviours that compete among each other. The agent/agent interactions are carried out by their social otherwise, the agent/environment interactions are expressed through the consumption of ecological resources in repression and satisfaction by social behaviours of the agent. In this work, we will present the structure and the formulation of our model. This model can capture emergent social phenomena such as globalization and polarization, and it can help to understand the social migration process. Copyright © 2013 John Wiley & Sons, Ltd.
Ultrasound estimation of birth weight in twin pregnancy: comparison of biometry algorithms in the STORK multiple pregnancy cohort
Authors: Khalil A. , D'Antonio F. , Dias T. , Cooper D. , Thilaganathan B. ,   on behalf of the Southwest Thames Obstetric Research Collaborative (STORK)
Published: November 2013

Objectives

The aims of this study were first, to ascertain the accuracy of formulae for ultrasonographic birth‐weight estimation in twin compared with singleton pregnancies and second, to assess the accuracy of sonographic examination in the prediction of birth‐weight discordance in twin pregnancies.

Methods

This was a retrospective cohort study including both singleton and twin pregnancies. Routine biometry was recorded and estimated fetal weight (EFW) calculated using 33 different formulae. Only pregnancies that delivered within 48 h of the ultrasound scan were included (4280 singleton and 586 twin fetuses). Differences between the EFW and actual birth weight (ABW) were assessed by percentage error, accuracy in predictions within ± 10 % and ± 15% of error and use of the Bland–Altman method. The accuracy of prediction of the different cut‐offs of birth‐weight discordance in twin pregnancies was also assessed using the area under the receiver–operating characteristics curve (AUC).

Results

The overall mean absolute percentage error was ≤ 10 % for 25 formulae in singleton pregnancies compared with three formulae in twin pregnancies. The overall predictions within ± 10% and ± 15% of the ABW were 62.2% and 81.5% in singleton and 49.7% and 68.5% in twin pregnancies, respectively. When the formulae were categorized according to the biometric parameters included, those based on a combination of head, abdomen and femur measurements showed the lowest mean absolute percentage error, in both singleton and twin pregnancies. The predictive accuracy for 25% birth‐weight discordance using the Hadlock 2 formula, as assessed by the AUC, was 0.87.

Conclusions

Ultrasound estimation of birth weight is less accurate in twin than in singleton pregnancies. Formulae that include a combination of head, abdomen and femur measurements perform best in both singleton and twin pregnancies. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd
Longitudinal changes in uterine artery Doppler and blood pressure and risk of pre‐eclampsia
Authors: Khalil A. , Garcia‐Mandujano R. , Maiz N. , Elkhaouli M. , Nicolaides K. H.
Published: November 2013

Objective

To investigate longitudinal changes in the uterine artery mean pulsatility index (UtA‐PI) and mean arterial pressure (MAP) in women who develop pre‐eclampsia (PE) and gestational hypertension (GH).

Methods

This was a prospective longitudinal study of singleton pregnancies identified by screening at 11 + 0 to 13 + 6 weeks' gestation as being at high risk for PE. Measurements of UtA‐PI and MAP were taken every 4 weeks until delivery and were compared in women who developed preterm PE, requiring delivery before 37 weeks, term PE and GH with those in women who remained normotensive.

Results

In the normal outcome group, UtA‐PI decreased with gestational age and MAP decreased between 12 and 24 weeks and then increased. In the preterm PE group, as compared to the normal group, UtA‐PI and MAP were higher from early pregnancy onward and the difference for both increased with gestational age. In the term PE group, UtA‐PI was significantly increased only from 33 weeks onward and MAP was increased from 12 weeks onward but the difference from normal did not increase with gestation. In GH, UtA‐PI did not differ significantly from normal but MAP was higher from 12 weeks onward.

Conclusion

The study describes temporal changes in UtA‐PI and MAP in normal pregnancies and in women who develop PE and GH. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.
Kinetics of Carnitine Palmitoyltransferase I (CPT I) in Chinese sucker (Myxocyprinus asiaticus) Change with its Development
Authors: Liu Cai‐Xia , Luo Zhi , Hu Wei , Tan Xiao‐Ying , Zheng Jia‐Lang , Chen Qi‐Liang , Zhu Qing‐Ling
Published: November 2013

The present study was conducted to evaluate the ontogeny and kinetic of CPT I in several tissues of the Chinese sucker Myxocyprinus asiaticus. To this end, liver, muscle and intestine tissues were examined at five various developmental stages of Chinese sucker: newly‐hatched larvae, 68‐day‐old, 4‐month‐old, 1‐ and 2‐year‐old Chinese sucker, respectively. The total carnitine (TC) content in the liver increased from birth to 1‐year‐old Chinese sucker and then declined in the 2‐year‐old Chinese sucker. From the 68‐day‐old to the 1‐year‐old Chinese sucker, both free and total concentrations in muscle increased. Both acyl carnitine (AC) and TC concentrations in intestine were very variable at different stages. The ratio of AC to free carnitine (FC) in liver progressively increased from hatching to 4 months, and declined at the age of 1 year, and then increased by 2 years. In muscle, the highest and lowest ratios of AC/FC were observed at 68‐days‐old and 4 month‐old Chinese sucker. The highest proportion of AC/FC in intestine was also observed at 68‐day‐old Chinese sucker. All the Chinese sucker larvae at hatching had a high value of the Michaelis constant (Km) for carnitine. Maximal velocity (Vmax) in intestine increased with age. Vmax in liver and muscle increased with age except a decrease at 4 months in liver and at 2 years in muscle. The FC concentration in the examined tissues at all developmental stages were less than the respective Km, indicating that Chinese suckers require supplemental carnitine in their food to ensure that CPT I activity is not constrained by carnitine availability.
Nationalism and Legitimation for Authoritarianism: A Comparison of Nicholas I and Vladimir Putin
Authors: Cannady Sean , Kubicek Paul
Published: November 2013

This article draws parallels between Tsar Nicholas I and current Russian President Vladimir Putin with respect to their use of nationalism to justify statist policies and political authoritarianism. Building upon insights by Alexander Gerschenkron about the economic development of “backwards” states, it argues that both Nicholas and Putin have rhetorically used Western concepts such as nationalism and democracy to legitimize their rule but have modified them to give them more statist content. Under Nicholas, this was exemplified in the tripartite (Orthodoxy, Autocracy, and Nationality) Official Nationality policy. Putin has emphasized patriotism, power, and statism to justify centralization of power and authoritarian policies. Putin's policies and rhetoric are strong analogs to those of Nicholas. Ultimately, the goal of this paper is to explain state-inspired Russian nationalism and how it has been aligned with authoritarian politics, as well as specifying similarities between present and past in Russia.
Modelling cellular signal communication mediated by phosphorylation dependent interaction with 14‐3‐3 proteins
Authors: Kleppe Rune , Ghorbani Sadaf , Martinez Aurora , Haavik Jan
Published: November 2013

The 14‐3‐3 proteins are important effectors of Ser/Thr phosphorylation in eukaryotic cells. Using mathematical modelling we investigated the roles of these proteins as effectors in signalling pathways that involve multi‐phosphorylation events. We defined optimal conditions for positive and negative cross‐talk. Particularly, synergistic signal interaction was evident at very different sets of binding affinities and phosphorylation kinetics. We identified three classes of 14‐3‐3 targets that all have two binding sites, but displayed synergistic interaction between converging signalling pathways for different ranges of parameter values. Consequently, these protein targets will respond differently to interventions that affect 14‐3‐3 binding affinities or phosphorylation kinetics.
N‐terminal signal sequence is required for cellular trafficking and hyaluronan‐depolymerization of KIAA1199
Authors: Yoshida Hiroyuki , Nagaoka Aya , Nakamura Sachiko , Tobiishi Megumi , Sugiyama Yoshinori , Inoue Shintaro
Published: November 2013

Recently, we disclosed that KIAA1199‐mediated hyaluronan (HA) depolymerization requires an acidic cellular microenvironment (e.g. clathrin‐coated vesicles or early endosomes), but no information about the structural basis underlying the cellular targeting and functional modification of KIAA1199 was available. Here, we show that the cleavage of N‐terminal 30 amino acids occurs in functionally matured KIAA1199, and the deletion of the N‐terminal portion results in altered intracellular trafficking of the molecule and loss of cellular HA depolymerization. These results suggest that the N‐terminal portion of KIAA1199 functions as a cleavable signal sequence required for proper KIAA1199 translocation and KIAA1199‐mediated HA depolymerization.
miR‐181b promotes cell proliferation and reduces apoptosis by repressing the expression of adenylyl cyclase 9 (AC9) in cervical cancer cells
Authors: Yang Lei , Wang Yan-Li , Liu Shang , Zhang Pei-Pei , Chen Zheng , Liu Min , Tang Hua
Published: November 2013

MicroRNAs are a class of small, endogenous, non‐coding RNAs that function as post‐transcriptional regulators. In this study, we found that miR‐181b promoted cell proliferation and inhibited cell apoptosis in cervical cancer cells. And we validated a new miR‐181b target gene, adenylyl cyclase 9 (AC9). miR‐181b restricted cAMP production by post‐transcriptionally downregulating AC9 expression. Phenotypic experiments indicated that miR‐181b and AC9 exerted opposite effects on cell proliferation and apoptosis.
HtrA1 is upregulated during RANKL‐induced osteoclastogenesis, and negatively regulates osteoblast differentiation and BMP2‐induced Smad1/5/8, ERK and p38 phosphorylation
Authors: Wu Xinghuo , Chim Shek Man , Kuek Vincent , Lim Bay Sie , Chow Siu To , Zhao Jinmin , Yang Shuhua , Rosen Vicki , Tickner Jennifer , Xu Jiake
Published: November 2013

Bone remodeling is regulated by secreted factors in the bone microenvironment. However, data regarding osteoclast‐derived factors that influence osteoblast differentiation are lacking. Here, we show that HtrA1 is produced as a secreted protein during osteoclastogenesis, and negatively regulates osteoblast differentiation. Exogenous addition of recombinant HtrA1 attenuates osteoblast differentiation and BMP2‐induced Smad1/5/8, ERK1/2 and p38 phosphorylation in pre‐osteoblasts. Our studies imply a unique mode of crosstalk in which HtrA1 is produced by both osteoclasts and osteoblasts and negatively regulates osteoblast differentiation, suggesting that HtrA1 may mediate the fine tuning of paracrine and autocrine regulations during bone remodeling processes.
Comparison of Balance Ability Between Patients With Type 2 Diabetes and With and Without Peripheral Neuropathy
Authors: Lim Kil‐Byung , Kim Dong Jun , Noh Jeong‐hyun , Yoo Jeehyun , Moon Jung‐Wha
Published: November 2013

Objectives

(1) To examine the effects of peripheral neuropathy on balance stability in patients with type 2 diabetes, and (2) to assess static and dynamic balance and functional limitations.

Design

A cross‐sectional study.

Setting

Outpatient clinic.

Patients

Subjects with type 2 diabetes and healthy subjects (n = 60) were divided into 3 groups: subjects with diabetes and with established peripheral neuropathy (diabetic peripheral neuropathy [DPN] group) (n = 17), subjects with diabetes and without peripheral neuropathy (diabetic control group) (n = 25), and subjects without diabetes (nondiabetic control [NDC] group) (n = 18).

Methods

Sensory impairment assessment, motor impairment assessment, and functional limitation assessment were assessed by using the Balance Master system.

Results

In motor impairment assessment, left‐to‐right directional control in the rhythmic weight shift was significantly poorer in the diabetic control group than in the NDC group during slow movement (P = .027). During fast movement, it was poorer in the DPN group than in the NDC group (P = .022). In the unilateral stance test of functional limitation assessment with both eyes open, the mean center of gravity sway velocity was significantly higher in the DPN group than in the NDC group (P = .011 for the left leg standing, P = .008 for the right leg standing) and higher in the DPN group than in the diabetic control group (P = .027 for the right leg standing). In the tandem walk test, walking speed was significantly lower in the DPN group than in the NDC group (P = .033), and end sway was significantly greater in the DPN group than in the NDC group (P = .020).

Conclusions

Analysis of the results of this study suggest that functional limitations may occur more in the patients with diabetes and with peripheral neuropathy, and dynamic balance stability may decrease more with the patients with diabetes than with the subjects without diabetes. Further studies on balance rehabilitation that concern dynamic balance stabilities and exercise abilities are needed in patients with diabetes.
Using the isotope dating of endocontact hybrid rocks for the age determination of mafic rocks (southern Siberian craton)
Authors: Gladkochub D.P. , Donskaya T.V. , Wingate M.T.D. , Mazukabzov A.M. , Pisarevsky S.A. , Kornilova T.A.
Published: November 2013

Geological observations and petrological and geochemical criteria are used to detect hybrid rocks at the endocontact of a dolerite dike. The hybrid rocks were produced when the material of a mafic intrusion mixed with a felsic melt. The latter was produced by the melting of the metamorphic rocks making up the Goloustnaya basement inlier of the Siberian craton, under the thermal effect of the intruded dike. Two age groups of zircon have been identified in the hybrid rock by SHRIMP analysis. The Paleoproterozoic age of inherited zircon (1902, 1864, 1859, and 1855 Ma) reflects the contribution of ancient sources to the hybrid-rock composition. The young, primary-magmatic, zircon grains, produced by melting at the endocontact of the mafic intrusion (494 ± 5 Ma), are coeval with the hybrid rocks, and their age indicates when the mafic rocks intruded the metamorphic framework. Dikes of close age, with similar geochemical characteristics, are present on the vast southern margin of the Siberian craton—from Goloustnaya to Biryusa salients.
A record of the behavior of the geomagnetic field in the sediments of Lake Baikal (BDP-99 borehole)
Authors: Krainov M.A. , Peskov A.Yu. , Kosynkin A.V. , Kuz’min M.I.
Published: November 2013

The relative paleointensity of sedimentation is studied for sediments stripped by deep-water drilling in Lake Baikal (BDP-99 borehole). Two intervals are considered: 0–420 ka (Brunhes chron) and 1.05–1.09 Ma (before, during, and after the Matuyama–Jaramillo reversal). For these intervals, curves of the ideal magnetization of samples are plotted.

The paleointensity data obtained along the borehole section reveal four excursions for the Baikal sediments whose identification on the inclination–depth curve is complicated.

The lower part of the section (Matuyama–Jaramillo subzones) shows a paleointensity decrease by a factor of five or more relative to periods of invariable polarity.
Such stuff as psychoses are made on?
Authors: D'Agostino Armando , Scarone Silvio
Published: November 2013

In her target article, Sue Llewellyn concludes that an unconstrained form of consciousness is necessary for the elaboration of meaningful associations. Unlike the author's view that dedifferentiation of memory encoding processes across wakefulness and sleep determines schizophrenia, our proposal suggests this mechanism could reflect a common neurobiological substrate for psychosis across several different diagnostic domains.
A compromise between competing forces dominating the diversity of aragonite structures
Authors: Wang Han , Han Yongsheng
Published: November 2013

A compromise between competing forces dominates the diversity of material structures.
Terahertz quantum-well photodetectors: Design, performance, and improvements
Authors: Zhang S. , Wang T. M. , Hao M. R. , Yang Y. , Zhang Y. H. , Shen W. Z. , Liu H. C.
Published: November 2013

Theoretical studies and numerical simulations on design, performance, and improvements of terahertz quantum-well photodetector (THz QWP) are presented. In the first part of this paper, we discuss the device band structure resulting from a self-consistent solution and simulation results. First, the temperature dependence of device characteristics is analyzed. Next, we deduce the condition of optimal doping concentration for maximizing dark current limited detectivity Ddet* when QWP is lightly doped. Accordingly, unlike in previously published reports, doping concentration is not fixed and is selected by the above condition. In the second part of this paper, we propose two schemes for improving operation temperature. The first is to incorporate an optical antenna which focuses incident THz wave. Numerical results show that the QWP with peak frequency higher than 5.5 THz is expected to achieve background-noise-limited performance at 77 K or above when employing a 106 times enhancement antenna. The second scheme is to use a laser as the signal source to achieve photon-noise-limited performance (PLIP) at high temperatures. Simulations show that when operating below critical temperature QWPs in the range of 1 ∼ 7 THz can reach PLIP under practical illumination intensities.
Fundamental studies on the Cs dynamics under ion source conditions
Authors: Friedl R. , Fantz U.
Published: November 2013

The performance of surface conversion based negative hydrogen ion sources is mainly determined by the caesium dynamics. Therefore, fundamental investigations in vacuum and plasma are performed at a flexible laboratory setup with ion source parameters. Studies on the influence of Cs on the plasma parameters of H2 and D2 plasmas showed that ne and Te in the bulk plasma are not affected by relevant amounts of Cs and no isotopic differences could be observed. The coating of the vessel surfaces with Cs, however, leads to a considerable gettering of hydrogen atoms from the plasma volume and to the decrease of ne close to a sample surface due to the formation of negative ions.
Low-pressure line-shape study in molecular oxygen with absolute frequency reference
Authors: Domysławska J. , Wójtewicz S. , Cygan A. , Bielska K. , Lisak D. , Masłowski P. , Trawiński R. S. , Ciuryło R.
Published: November 2013

We present a line-shape analysis of the rovibronic R1 Q2 transition of the oxygen B band resolved by the Pound-Drever-Hall-locked frequency-stabilized cavity ring-down spectroscopy technique in the low pressure range. The frequency axis of the spectra is linked by the ultra-narrow diode laser to the optical frequency comb in order to measure the absolute frequency at each point of the recorded spectra. Experimental spectra are fitted with various line-shape models: the Voigt profile, the Galatry profile, the Nelkin-Ghatak profile, the speed-dependent Voigt profile, and the speed-dependent Nelkin-Ghatak profile with quadratic and hypergeometric approximations for the speed dependence of collisional broadening and shifting. The influences of Dicke narrowing, speed-dependent effects, and correlation between phase- and velocity-changing collisions on the line shape are investigated. Values of line-shape parameters, including the absolute frequency of the transition 435685.24828(46) GHz, are reported.
Experimental results of a dual-beam ion source for 200 keV ion implanter
Authors: Chen L. H. , Cui B. Q. , Ma R. G. , Ma Y. J. , Tang B. , Huang Q. H. , Jiang W. S. , Zheng Y. N.
Published: November 2013

A dual beam ion source for 200 keV ion implanter aimed to produce 200 keV H2+ and He+ beams simultaneously has been developed. Not suitable to use the analyzing magnet, the purity of beam extracted from the source becomes important to the performance of implanter. The performance of ion source was measured. The results of experiments show that the materials of inlet tube of ion source, the time of arc ionization in ion source, and the amount of gas flow have significant influence on the purity of beam. The measures by using copper as inlet tube material, long time of arc ionization, and increasing the inlet of gas flow could effectively reduce the impurity of beam. And the method using the gas mass flow controller to adjust the proportion of H2+ and He+ is feasible.
Adaptive spectral clustering with application to tripeptide conformation analysis
Authors: Haack Fiete , Fackeldey Konstantin , Röblitz Susanna , Scharkoi Olga , Weber Marcus , Schmidt Burkhard
Published: November 2013

A decomposition of a molecular conformational space into sets or functions (states) allows for a reduced description of the dynamical behavior in terms of transition probabilities between these states. Spectral clustering of the corresponding transition probability matrix can then reveal metastabilities. The more states are used for the decomposition, the smaller the risk to cover multiple conformations with one state, which would make these conformations indistinguishable. However, since the computational complexity of the clustering algorithm increases quadratically with the number of states, it is desirable to have as few states as possible. To balance these two contradictory goals, we present an algorithm for an adaptive decomposition of the position space starting from a very coarse decomposition. The algorithm is applied to small data classification problems where it was shown to be superior to commonly used algorithms, e.g., k-means. We also applied this algorithm to the conformation analysis of a tripeptide molecule where six-dimensional time series are successfully analyzed.
Formation of magnetic discontinuities through superposition of force-free magnetic fields: Periodic boundaries
Authors: Kumar Dinesh , Bhattacharyya R. , Smolarkiewicz P. K.
Published: November 2013

In ideal magnetohydrodynamics characterized by an infinite electrical conductivity, the magnetic flux across an arbitrary fluid surface is conserved in time. The magnetofluid then can be partitioned into contiguous subvolumes of fluid, each of which entraps its own subsystem of magnetic flux. During dynamical evolution of the magnetofluid, these subvolumes press into each other; and in the process, two such subvolumes may come into direct contact while ejecting a third interstitial subvolume. Depending on the orientations of magnetic fields of the two interacting subvolumes, the magnetic field at the common surface of interaction may become discontinuous and a current sheet is formed there. This process of current sheet formation and their subsequent decay is believed to be a plausible mechanism for coronal heating and may also be responsible for various eruptive phenomena at the solar corona. In this work, we explore this theoretical concept through numerical simulations of a viscous, incompressible magnetofluid characterized by infinite electrical conductivity. In particular, we show that if the initial magnetic field is prescribed by superposition of two linear force-free fields with different torsion coefficients, then formation of current sheets are numerically realizable in the neighborhood of magnetic nulls.
Raman scattering studies of strain effects in (100) and (311)B GaAs1−xBix epitaxial layers
Authors: Steele J. A. , Lewis R. A. , Henini M. , Lemine O. M. , Alkaoud A.
Published: November 2013

We report room-temperature Raman studies of strained (100) and (311)B GaAs1−xBix epitaxial layers for x ≤ 0.039. The Raman spectra exhibit a two-mode behavior, as well as disorder-activated GaAs-like phonons. The experimental results show that the GaAs-like LO(Γ) mode experiences a strong composition-dependent redshift as a result of alloying. The peak frequency decreases linearly from the value for pure GaAs (∼293 cm−1) with the alloyed Bi fraction x and the introduced in-plane lattice strain ε∥, by ΔωLO=Δωalloy−Δωstrain. X-ray diffraction measurements are used to determine x and ε∥ allowing Δωalloy to be decoupled and is estimated to be −12(±4) cm−1/x for (100) GaAs1−xBix. ΔωLO is measured to be roughly double for samples grown on (311)B-oriented substrates to that of (100) GaAs. This large difference in redshift is accounted for by examining the Bi induced strain, effects from alloying, and defects formed during high-index (311)B crystal growth.