bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oligothiophene‐Functionalized Benzene and Tetrathienoanthracene: Effect of Enhanced π‐Conjugation on Optoelectronic Properties, Self‐Assembly and Device Performance
Authors: Leitch Alicea A. , Stobo Kimberly A. , Hussain Bashir , Ghoussoub Mireille , Ebrahimi‐Takalloo Saeedeh , Servati Peyman , Korobkov Ilia , Brusso Jaclyn L. 
Published: July 2013

AbstractThe versatility of fourfold Stille coupling to afford oligothiophene‐functionalized tetrathienoanthracene (TTA) and benzene derivatives is described. The influence of the larger, more rigid TTA core on the electronic and structural properties was investigated. Comparative optical and electrochemical studies demonstrate a diminishing HOMO–LUMO gap as the length of the oligothiophene chain increases, with the rigid TTA compounds exhibiting lower energy gaps than the more flexible benzene analogues. X‐ray crystallography studies reveal that the thiophene‐substituted TTA structure consists of slipped π‐stacks with several close intrastack π–π interactions; no close contacts are observed for the benzene derivative due to twisting of the thiophene ligands out of plane. Consequently, the molecules in the benzene analogue are isolated from their neighbours. The thiophene and bithiophene functionalised TTA compounds were fabricated into OTFT devices in bottom‐contact configuration and exhibited mobilities of ca. 10–4 cm2 V–1 s–1 and on/off ratios of more than four orders of magnitude.
Insight into the Capacitive Performance of Sulfur‐Doped Nanoporous Carbons Modified by Addition of Graphene Phase
Authors: Seredych Mykola , Singh Kavindra , Bandosz Teresa J. 
Published: July 2013

AbstractThe composites of nanoporous carbon and graphene were prepared by carbonization of mixed sulfonate‐based polymers and graphite oxide. Addition of the graphene phase modified the texture and chemistry of the final products. The materials show high electrochemical capacity in spite of the relatively low surface area. The good performance is linked to the presence of sulfur in the small pores, which brings a positive charge on carbon atoms and thus increases the attraction to anions, to the sulfones, sulfoxides and quinones in larger pores, which undergo Faradaic reactions, and to the balanced content of oxygen groups, which provides the wettability.
Thin Electrolytes on Metal‐Supported Fuel Cells
Authors: Vieweger S. , Mücke R. , Menzler N. H. , Buchkremer H. P. 
Published: July 2013

AbstractThis work focuses on the deposition of thin‐film electrolytes. Sol–Gel Spin‐coating technique has been used to create thin films and subsequent characterization of the different sub‐surfaces has been undertaken. The substrates are composed of ferritic oxide strengthened Fe–Cr alloy (ITM). A common challenge in coating these supports is their high roughness and porosity in comparison with state‐of‐the‐art ceramic substrates. Here, the nickel and 8 mol.% yttria‐stabilized zirconia (8YSZ) based anode is made of graded layers, which reduces the roughness and porosity of the metal support. The quality of the thin spin‐coated electrolyte‐layers depends on the microstructure of the sub‐surface. Influencial variables are the surface roughness, the pore size and its depth. To understand the dependencies between these variables and the coating properties, analyses with various optical measurement methods have been carried out prior to coating. Standard roughness detection using optical profilometry and confocal laser scanning microscopy were compared for surface characterization. The Sobel edge detection method was used to analyze images and was able to clearly reveal defects. The fabricated electrolytes have a thickness ∼0.5 μm with leak rates of 1 – 10×10–4 (hPa dm3 s–1 cm–2) against air of metallic supported cells with a reduced anode, which are comparable to those of anode‐supported cells.
Effect of Contact Method between Interconnects and Electrodes on Area Specific Resistance in Planar Solid Oxide Fuel Cells
Authors: Wu W. , Wang G. L. , Guan W. B. , Zhen Y. F. , Wang W. G. 
Published: July 2013

AbstractIn this work, interconnect/electrode sheet/interconnect sandwiches are assembled by designing interfacial contact between interconnects and electrodes for planar solid oxide fuel cells (SOFCs). Their area specific resistance (ASR) values of different contact methods under isothermal oxidation and thermal cycling are recorded by four‐point method. The ASR of SUS430/Ni–YSZ/SUS430 anode sandwich with NiO current collecting layer is close to that of anode sandwich without NiO current collecting layer during isothermal operation, but smaller and more stable during thermal cycling. Meanwhile, the lowest ASR is obtained in SUS430/LSM–YSZ/SUS430 cathode sandwich with LSM coated interconnect and LSM current collecting layer among various contact methods between interconnects and cathodes, and remains constant under isothermal oxidation and thermal cycling. Contact resistance between cathodes and interconnects is the main source of the SOFC stack resistance. A real stack with three anode‐supported cells is assembled and tested under thermal cycling to verify the effect of different contact methods between interconnects and electrodes on performance of stack repeating unit. The degradation rate and ASR values of repeating unit inside the stack indicate that the contact between LSM coated interconnect and LSM current collecting layer on cathode side is the optimized contact.
Are synthetic scaffolds suitable for the development of clinical tissue‐engineered tubular organs?
Authors: Del Gaudio Costantino , Baiguera Silvia , Ajalloueian Fatemeh , Bianco Alessandra , Macchiarini Paolo 
Published: July 2013

AbstractTransplantation of tissues and organs is currently the only available treatment for patients with end‐stage diseases. However, its feasibility is limited by the chronic shortage of suitable donors, the need for life‐long immunosuppression, and by socioeconomical and religious concerns. Recently, tissue engineering has garnered interest as a means to generate cell‐seeded three‐dimensional scaffolds that could replace diseased organs without requiring immunosuppression. Using a regenerative approach, scaffolds made by synthetic, nonimmunogenic, and biocompatible materials have been developed and successfully clinically implanted. This strategy, based on a viable and ready‐to‐use bioengineered scaffold, able to promote novel tissue formation, favoring cell adhesion and proliferation, could become a reliable alternative to allotransplatation in the next future. In this article, tissue‐engineered synthetic substitutes for tubular organs (such as trachea, esophagus, bile ducts, and bowel) are reviewed, including a discussion on their morphological and functional properties. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 2427–2447, 2014
Quantification of structural compliance of aged human and porcine aortic root tissues
Authors: Li Kewei , Wang Qian , Pham Thuy , Sun Wei 
Published: July 2013

AbstractThe structural compliance of the aortic root has a significant implication for valve procedures such as transcatheter aortic valve implantation and valve‐sparing aortic root replacement. However, a detailed quantification of human aortic root structural compliance, particularly in different regions, has been incomplete. In this study, the structural properties of human aortic roots (81 ± 8.74 years, n = 10) were characterized and compared with those of porcine ones (6–9 months, n = 10) using a vessel pressure‐inflation test. The test involved tracking three‐dimensional deformation of the markers affixed on the different surface regions of the aortic roots, including the three sinuses: the noncoronary sinus (NCS), the left‐coronary sinus (LCS), and the right‐coronary sinus (RCS), and at three regions along the longitudinal direction of each sinus: the upper sinus (US), the middle sinus (MS), and the lower sinus (LS), and the ascending aorta (AA) region above the NCS. We found that tissue stiffness in physiological pressure range was similar among the three human sinuses. A variation in regional structural stiffness of human aorta was observed. In the circumferential direction, the LS regions were the stiffest in the LCS and RCS, whereas NCS had relatively uniform stiffness. In the longitudinal direction, the human AA regions were more compliant than all sinuses. There was a significant difference in tissue stiffness between human and porcine aortic tissues, suggesting that the mechanical properties of porcine tissues may not be analogous to aged human ones. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 2365–2374, 2014.
Synthetic Transformations of Sulfur‐Substituted 4‐Quinolizidinones
Authors: Chou Shang‐Shing P. , Kao Chao‐Hsiang 
Published: July 2013

AbstractSulfur‐substituted 4‐quinolizidinones, previously prepared by aza‐Diels‐Alder reactions and ring‐closing metathesis, are now subjected to further synthetic transformations. Formal synthesis of cermizine C and 5‐epi‐cermizine C, and some other useful reactions have been achieved.
On the spatial distribution of decameter‒scale subauroral ionospheric irregularities observed by SuperDARN radars
Authors: de Larquier S. , Ponomarenko P. , Ribeiro A. J. , Ruohoniemi J. M. , Baker J. B. H. , Sterne K. T. , Lester M. 
Published: July 2013

AbstractThe midlatitude Super Dual Auroral Radar Network (SuperDARN) radars regularly observe nighttime low‒velocity Sub‒Auroral Ionospheric Scatter (SAIS) from decameter‒scale ionospheric density irregularities during quiet geomagnetic conditions. To establish the origin of the density irregularities responsible for low‒velocity SAIS, it is necessary to distinguish between the effects of high frequency (HF) propagation and irregularity occurrence itself on the observed backscatter distribution. We compare range, azimuth, and elevation data from the Blackstone SuperDARN radar with modeling results from ray tracing coupled with the International Reference Ionosphere assuming a uniform irregularity distribution. The observed and modeled distributions are shown to be very similar. The spatial distribution of backscattering is consistent with the requirement that HF rays propagate nearly perpendicular to the geomagnetic field lines (aspect angle ≤1°). For the first time, the irregularities responsible for low‒velocity SAIS are determined to extend between 200 and 300 km altitude, validating previous assumptions that low‒velocity SAIS is an F‒region phenomenon. We find that the limited spatial extent of this category of ionospheric backscatter within SuperDARN radars' fields‒of‒view is a consequence of HF propagation effects and the finite vertical extent of the scattering irregularities. We conclude that the density irregularities responsible for low‒velocity SAIS are widely distributed horizontally within the midlatitude ionosphere but are confined to the bottom‒side F‒region.
The relationship between the Antarctic oscillation and blocking events over the South Pacific and Atlantic Oceans
Authors: Damião Mendes Monica Cristina , Cavalcanti Iracema Fonseca Albuquerque 
Published: July 2013

ABSTRACTIt is known that blocking events have impacts on the behaviour of transient systems and affect the weather in southern continental regions of the Southern Hemisphere. Since the main mode of variability in Southern Hemisphere, the annular mode, or Antarctic Oscillation (AAO), changes the extratropical atmospheric circulation, the blocking characteristics over Pacific and Atlantic Oceans are analysed in this study, in terms of the two opposing phases of theAAO. The characteristics of atmospheric flow patterns and blocking events are analysed as a function of season during the period 1979–2000. The relative frequency of blocked days is different for eachAAOphase. Maximum duration and number of events over the Southwestern Pacific and South Atlantic regions occur in the positive phase, while the blocking activity over the Southeastern Pacific region is similar in the two phases but the persistence is higher in the negative phase. The atmospheric anomalous centres associated with middle latitude and polarAAOsignals, as well as the behaviour of subtropical and polar jets are discussed in relation to the blocking characteristics. Convection over South America is analysed for blocking periods in eachAAOphase and is discussed based on anomalous circulation in each phase. Wavetrain patterns over the South Pacific and variations in intensity of jet streams induce anomalous circulation over South America, which are associated with the track and persistence of transient systems over Southeastern South America and with convection over the continent.
Detecting climate variability signals in long air temperature records
Authors: Kärner O. , de Freitas C. R. 
Published: July 2013

ABSTRACTThis work introduces a new climate description scheme based on a long range statistical model fitted to local daily temperature anomaly series. The appropriate model can be considered as a sum of two processes, namely, stationary white noise (WN) and nonstationary random walk (RW). In the case of local series, the variance of the WN component appears to be much larger than that for the generator of RW (also a WN, but independent on the first one). Such a situation enables us to approximate the range of variability for local temperature anomalies by means of the standard deviation of the stationary WN component of the model. This means that the climate description splits into two parts; one describes ordinary and the other extreme weather events. This paper presents a detailed description of that approach using the air temperature series from Stockholm (1756–2011) as an example. The scheme produced here enables us to see that large weather variability does not always mean climate variability. It separates climate and weather scale variability, which is important for precise determination of climate variability and does not confuse the weather and climate time scales in climate description.
Improvement in the detection rate of PJI in total hip arthroplasty through multiple sonicate fluid cultures
Authors: Janz V. , Wassilew G.I. , Hasart O. , Tohtz S. , Perka C. 
Published: July 2013

ABSTRACTThe microbiological culture of sonicate fluid (SFC) of explanted endoprosthetic components has increased the rate of bacterial isolation in comparison to conventional microbiological methods. However, this creates the problem of interpreting cases of singular bacterial isolation through SFC, while all other microbiological samples remain negative. The aim of this study was to reference these singular positive SFC against, the histological classification of the periprosthetic membrane (PM), and the utilization of multiple SFC (separate sonication of individual endoprosthetic components). In this prospective study we compared the effect of multiple SFC for detection of periprosthetic joint infection (PJI) in patients with total hip revision surgery. All microbiological results were referenced against PM. Of the 102 cases there were 37 cases of PJI. Single SFC achieved the highest sensitivity of all individual parameters with 89% and a specificity of 72%. When multiple SFC were employed the sensitivity and specificity increased to 100%. There was a concordance of 86% between the PM and SFC. SFC achieved the highest sensitivity and it was possible to further improve the sensitivity and specificity when using multiple cultures. Multiple SFC and PM are beneficial to help reference singular bacterial isolations and achieve the diagnosis of PJI. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:2021–2024, 2013
Body composition in 18‐ to 88‐year‐old adults—comparison of multifrequency bioimpedance and dual‐energy X‐ray absorptiometry
Authors: Sillanpää Elina , Cheng Sulin , Häkkinen Keijo , Finni Taija , Walker Simon , Pesola Arto , Ahtiainen Juha , Stenroth Lauri , Selänne Harri , Sipilä Sarianna 
Published: July 2013

ObjectiveThis study compared bioimpedance analysis (BIA) in the assessment of body composition with dual‐energy X‐ray absorptiometry (DXA) in 18‐ to 88‐year‐old adults.Design and MethodsBody composition of 882 adults was estimated by eight‐polar BIA and DXA. In addition, estimates of lean mass, fat mass, and percentage of fat were investigated across a range of age and leisure time physical activity (LTPA) groups.ResultsCompared to DXA, larger lean masses (mean difference 2.9 and 1.6 kg) and smaller fat masses (3.1 and 2.6 kg) were estimated by BIA in both women and men, respectively. Differences between the methods' mean values were evident in all age and LTPA groups, except in the oldest men (over 70 years). Age, waist circumference, grip strength, and LTPA explained 21% or less of the variance observed in the differences between methods.ConclusionsCompared to DXA, BIA provided systematically different body composition estimates throughout the adult age span with considerable amount of intraindividual variation. The differences between estimates may be related to the BIAs' algorithm or body geometry or composition of the population used in this study. Knowledge about the methodological limitations and device comparability is essential for researchers, clinicians, and persons working in rehabilitation and sport centers.
Self‐triggered linear quadratic networked control
Authors: Souza M. , Deaecto G. S. , Geromel J. C. , Daafouz J. 
Published: July 2013

SUMMARYThis paper deals with networked control systems design, under the constraint of limited bandwidth on the communication channel. A linear quadratic problem for a fixed sampling period is solved, and this result is used for the development of and performance indexes, yielding to the statement and solution of and optimal control problems. Finally, a self‐triggered controller is designed with a switched system approach in order to improve performance. Several examples are presented in order to illustrate the validity of the developed theory. Copyright © 2013 John Wiley & Sons, Ltd.
ANALYZING SELF‐ORGANIZED LOCAL GOVERNANCE INITIATIVES: ARE THERE INSIGHTS FOR DECENTRALIZATION REFORMS?
Authors: Wunsch James S. 
Published: July 2013

SUMMARYIn spite of the great enthusiasm and arguments supporting decentralization in Africa, its performance has frequently fallen well below expectations. However, a number of self‐initiated, local governance efforts have been quite successful. The article finds that all governance initiatives face a number of collective action problems that they must overcome to succeed. These include issues of collective choice, free riding, principal–agency, and constitutional design. The article explores two cases of locally initiated self‐governance initiatives where smaller population size, the ability to focus on only a few services, and the ability flexibly to redesign their institutions were important in their success in overcoming these governance challenges. In one case, challenge by and negotiation with formal governance institutions furthered their success. Copyright © 2013 John Wiley & Sons, Ltd.
Preparation of Magnesium‐based Hydrogen Storage Materials and Their Effect on the Thermal Decomposition of Ammonium Perchlorate
Authors: Liu Leili , Xin Jingjing , Ma Feng , Zhi Chunlei , Li Fengsheng 
Published: July 2013

AbstractMagnesium‐based hydrogen storage materials (MgH2, Mg2NiH4, and Mg2Cu‐H) were prepared and their structures were determined by XRD and ICP investigations. Mg2NiH4has a monoclinic crystal structure and Mg2Cu‐H is a mixture of MgCu2and MgH2. The effects of magnesium‐based hydrogen storage materials on the thermal decomposition of ammonium perchlorate (AP) were studied by thermal analysis (DSC). It was found that magnesium‐based hydrogen storage materials show obvious boosting effects on the thermal decomposition of AP. The thermal decomposition peak temperature of AP was decreased, while the heat release of the decomposition of AP was increased. It was revealed that the effects of magnesium‐based hydrogen storage materials on the decomposition of AP become stronger with increasing content. The influence mechanism on the thermal decomposition of AP is suggested as follows: hydrogen released from magnesium‐based hydrogen storage materials and Mg, Ni, or Cu react with the decomposed products of AP.
Influence of atmospheric and sea surface temperature on the size of hurricane Catarina
Authors: Radu Raluca , Toumi Ralf , Phau Jared 
Published: July 2013

AbstractThe factors that influence the size of tropical cyclones (TCs) are not completely understood. High‐resolution numerical simulations of hurricane Catarina in the South Atlantic indicate that the TC size increases proportionally to the surface latent heat flux, when atmospheric and sea surface temperature (SST) are increased. The TC size is defined as the area enclosed by three wind thresholds: gale‐force winds, damaging‐force winds and hurricane‐force winds. The enlargement increases sharply with the wind threshold. Depending on the wind threshold, the area can increase by more than an order of magnitude when air and sea temperature are both increased by 2 °C. There is a clear linear relationship between the size increase and the latent heat flux during the TC lifetime. The size effect is driven initially by the enhanced air–sea moisture contrast and the surface winds become predominant only in the later stages. Temperature changes may therefore have a profound impact on cyclone size.
Restoration prospects for Heitutan degraded grassland in the Sanjiangyuan
Authors: Li Xi-lai , Perry George L. W. , Brierley Gary , Gao Jay , Zhang Jing , Yang Yuan-wu 
Published: July 2013

Abstract
In many ecosystems ungulates have coexisted with grasslands over long periods of time. However, high densities of grazing animals may change the floristic and structural characteristics of vegetation, reduce biodiversity, and increase soil erosion, potentially triggering abrupt and rapid changes in ecosystem condition. Alternate stable state theory provides a framework for understanding this type of dynamic. In the Sanjiangyuan atop the Qinghai-Tibetan plateau (QTP), grassland degradation has been accompanied by irruptions of native burrowing animals, which has accentuated the loss of ground cover. Severely degraded areas of alpine meadows are referred to as ‘Heitutan’. Here, using the framework of alternate stable state theory, we describe the proximate and ultimate drivers of the formation of Heitutan on the QTP, and we assess prospects for recovery, in relation to the degree of biophysical alteration, of these alpine meadows. Effective rehabilitation measures must address the underlying causes of degradation rather than their symptoms. Heitutan degradation is not uni-causal. Rather it reflects different mechanisms operating at different spatio-temporal scales across this vast region. Underlying causes include overly aggressive exploitation of the grasslands (e.g. overgrazing), amplification of grazing and erosion damage by small mammals when outbreaks occur, and/or climate change. Given marked variability in environmental conditions and stressors, restorative efforts must vary across the region. Restoration efforts are likely to yield greatest success if moderately and severely degraded areas are targeted as the first priority in management programmes, before these areas are transformed into extreme Heitutan.