bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioreactors for heart valve tissue engineering: a review
Authors: Amrollahi Pouya , Tayebi Lobat 
Published: September 2015

AbstractBioreactors have great potential in the successful development of tissue‐engineered heart valve replacements, both at the research stage and in commercial platforms. Their ability to mimick the chemical and physiological conditions of the body has allowed researchers to study in vitro cellular responses, and this has helped in the fabrication of better and more efficient tissues in vivo. Use of different bioreactors, such as, rotating, dynamic flexure, cyclic stretch and pulsatile bioreactors, in tissue engineering of heart valves has been widely investigated. However, this research is still at its early stage, and many critical issues need to be resolved to make tissue engineered heart valves sufficiently reliable for clinical applications. In the following article, after a brief introduction to the structure and role of heart valves, the efforts of tissue engineers in designing heart valves using different bioreactors is described. © 2015 Society of Chemical Industry
When are overqualified employees creative? It depends on contextual factors
Authors: Luksyte Aleksandra , Spitzmueller Christiane 
Published: September 2015

SummaryThe research on perceived overqualification has mainly examined its negative consequences. Defined, employees who feel overqualified have surplus talent and thus can be excellent workers if managed properly; yet, empirical evidence in this domain is lacking. Building on person–environment fit theory, this research explored whether, when, and how employees who feel overqualified can engage in creative performance. The results of a multi‐source field study (N = 113 employees and 19 supervisors) supported theoretical predictions. Perceived overqualification was related positively to supervisor‐rated creative performance when these workers felt supported and appreciated and successfully negotiated developmental idiosyncratic deals. Opportunities to mentor others had an impact on the relationship between perceived overqualification and supervisor‐rated creativity, although the simple slopes were non‐significant. This study is novel in that it unpacked actionable steps that organizations can utilize to motivate this large segment of workforce to use their surplus qualifications constructively by, for example, engaging in creative performance. Copyright © 2015 John Wiley & Sons, Ltd.
Chronological variations in handaxes: patterns detected from fluvial archives in north‐west Europe
Authors: Bridgland David R. , White Mark J. 
Published: September 2015

ABSTRACTThe use of handaxe morphology as a cultural and temporal marker within the Quaternary Lower–Middle Palaeolithic record has had a very chequered history, and abuses in the past have led recent generations of archaeologist to reject it out of hand. In Britain, however, advances in dating Pleistocene sediments, setting their ages within a framework of ∼11 glacial–interglacial cycles over the past 1 Ma, has revealed several patterns in technology and morphology that must be related to changing practices and cultural preferences over time. These are not predictable, nor are they linear, but nevertheless they may aid understanding of the movements of different peoples in and out of Britain over the past 500 000 years. It is also clear that such patterns are to be expected over a much wider region of the nearby continent, although they might not be identical, or even similar, to those established for southern Britain. This paper extends from explanation of the British patterns to an exploration of the extent to which something comparable can be recognized in neighbouring areas of continental Europe: a baseline for a planned collaborative survey of data from the Acheulean of north‐west European river systems.
Aquaculture depredation by double‐crested cormorants breeding in Eastern North America
Authors: Craig Elizabeth C. , King D. Tommy , Sparks Jed P. , Curtis Paul D. 
Published: September 2015

ABSTRACTThe double‐crested cormorant (Phalacrocorax auritus) has undergone population expansion throughout much of its historical range since the 1970s, resulting in increased pressure on foraging habitats including real and perceived competition with commercial and sport fisheries and impacts on the aquaculture industry. The specific objectives of this study were to determine the stable isotope ratios of birds wintering at aquaculture facilities and natural freshwater and marine habitats, and to determine what percent of birds at distinct breeding colonies wintered in each of these habitats. We exploited natural variation in isotopic ratios of carbon, nitrogen, and sulfur (from feathers) to determine the winter habitat use (i.e., aquaculture, natural freshwater, or marine) of birds collected on their summer breeding grounds in the eastern United States (from Minnesota to Vermont). The distribution of winter habitat use varied significantly across breeding colonies and between male and female cormorants. More specifically, use of aquaculture winter habitat was most prevalent in birds breeding in Lake Huron and Lake Erie. Overall, aquaculture habitats were used more by males, and marine habitats were used more by females. The stable isotope approach used in this study provided dietary confirmation of previously observed migratory patterns in the double‐crested cormorant. Because aquaculture was primarily used by males, and these males migrated to a broad range of breeding colonies, we suggest that targeting breeding birds to reduce aquaculture depredation is a less efficient strategy than managing birds at depredation sites on the wintering grounds. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
A multi‐laser flow cytometry method to measure single cell and population‐level relative fluorescence action spectra for the targeted study and isolation of phytoplankton in complex assemblages
Authors: Thompson Anne W. , van den Engh Ger 
Published: September 2015

AbstractDiscerning the diversity, abundance, and functional role of distinct phytoplankton groups is essential to ecological study of aquatic systems. Flow cytometry is a widely used method to rapidly identify and quantify individual phytoplankton cells. Here, we present a new flow cytometry method that uses up to five excitation colors to determine the relative fluorescence action spectra of phytoplankton within complex assemblages, thus leveraging the precise and high‐throughput capabilities of flow cytometry and the unique combinations of photosynthetic pigments in phylogenetically related groups of phytoplankton. First, we tested the method on cultivated Synechococcus of known pigment composition and genotype then we applied the method to a natural phytoplankton assemblage where we determined the relative fluorescence action spectra of numerous distinct populations. By coupling multi‐laser flow cytometry to cell sorting we demonstrated that natural phytoplankton populations with similar relative fluorescence action spectra belonged to the same taxonomic classes based on 18S rRNA gene phylogeny. This method will be instrumental in studying the ecology of distinct phytoplankton populations within complex microbial communities through spectral analysis of individual cells, identification of unique populations, and cell sorting for downstream applications such as enrichment for isolation, genome assembly, and linkage of chromatic and genetic information in a predictive fashion.
Acne scarring: A review of available therapeutic lasers
Authors: Cohen Brandon E. , Brauer Jeremy A. , Geronemus Roy G. 
Published: September 2015

Background and ObjectiveThe utilization of lasers in dermatology has greatly expanded in recent decades. Acne scarring is a common indication in which lasers play an important therapeutic role.Study Design/Materials and MethodsAvailable lasers include traditional ablative lasers, such as carbon dioxide and erbium lasers, traditional non‐ablative lasers, such as neodymium, diode, alexandrite, pulsed dye lasers and intense pulse light, as well as both ablative, and non‐ablative fractional laser systems.ConclusionWe sought to provide a framework for understanding the various types of lasers available to treat acne scars and review the primary literature pertaining to the efficacy, safety, and advantages of each laser discussed. Lasers Surg. Med. 48:95–115, 2016. © 2015 Wiley Periodicals, Inc.
Brain contrasting ability of blood‐brain‐barrier–permeable nitroxyl contrast agents for magnetic resonance redox imaging
Authors: Matsumoto Ken‐ichiro , Yamasaki Toshihide , Nakamura Mizuki , Ishikawa Junji , Ueno Megumi , Nakanishi Ikuo , Sekita Aiko , Ozawa Yoshikazu , Kamada Tadashi , Aoki Ichio , Yamada Ken‐ichi 
Published: September 2015

PurposeThe detailed in vivo T1‐weighted contrasting abilities of nitroxyl contrast agents, which have been used as redox responsive contrast agents in several magnetic resonance‐based imaging modalities, in mouse brain were investigated.MethodsDistribution and pharmacokinetics of five types of five‐membered‐ring nitroxyl radical compound were compared using T1‐weighted MRI.ResultsThe blood–brain barrier (BBB) ‐impermeable 3‐carboxy‐2,2,5,5‐tetramethylpyrrolidine‐N‐oxyl (CxP) could not be distributed in the brain. The slightly lipophilic 3‐carbamoyl‐2,2,5,5‐tetramethylpyrrolidine‐N‐oxyl (CmP) showed slight distribution only in the ventricle, but not in the medulla and cortex. The amphiphilic 3‐methoxy‐carbonyl‐2,2,5,5‐tetramethyl‐pyrrolidine‐N‐oxyl (MCP) had good initial uniform distribution in the brain and showed typical 2‐phase signal decay profiles. A brain‐seeking nitroxyl probe, acetoxymethyl‐2,2,5,5‐tetramethyl‐pyrrolidine‐N‐oxyl‐3‐carboxylate (CxP‐AM), showed an accumulating phase, and then its accumulation was maintained in the medulla and ventricle regions, but not in the cortex. The lipophilic 4‐(N‐methyl piperidine)−2,2,5,5‐tetramethylpyrroline‐N‐oxyl (23c) was well distributed in the cortex and medulla, but slightly in the ventricle, and showed relatively rapid linear signal decay.ConclusionNitroxyl contrast agents equipped with a suitable lipophilic substitution group could be BBB‐permeable functional contrast agents. MR redox imaging, which can estimate not only the redox characteristics but also the detailed distribution of the contrast agents, is a good candidate for a theranostic tool. Magn Reson Med 76:935–945, 2016. © 2015 Wiley Periodicals, Inc.
Quantitative susceptibility mapping using a superposed dipole inversion method: Application to intracranial hemorrhage
Authors: Sun Hongfu , Kate Mahesh , Gioia Laura C. , Emery Derek J. , Butcher Kenneth , Wilman Alan H. 
Published: September 2015

PurposeTo investigate gradient‐echo phase errors caused by intracranial hemorrhage (ICH) of low signal magnitude, and propose methods to reduce artifacts from phase errors in quantitative susceptibility mapping (QSM) of ICH.MethodsTwo QSM methods are proposed: (1) mask‐inversion that masks the phase of low signal magnitude regions, and (2) ICH magnetic dipole field isolation followed by susceptibility superposition using multiple boundaries for background field removal. The reconstruction methods were tested in eight subjects with ICH using standard single‐echo susceptibility‐weighted imaging at 1.5 Tesla with 40 ms echo time. Different phase unwrapping algorithms were also compared.ResultsSignificant phase errors were evident inside ICHs with low signal magnitude. The mask‐inversion method recovered susceptibility of ICH in numerical simulation and minimized phase error propagation in patients with ICH. The additional superposed dipole inversion process substantially suppressed and constrained streaking artifacts in all subjects. Using the proposed superposition method, ICH susceptibilities measured from long and short echo times were similar. Laplacian based phase unwrapping substantially underestimated the ICH dipole field as compared to a path‐based method.ConclusionThe proposed methods of mask‐inversion as well as ICH isolation and superposition can substantially reduce artifacts in QSM of ICH. Magn Reson Med 76:781–791, 2016. © 2015 Wiley Periodicals, Inc.
A model‐based reconstruction technique for quantitative myocardial perfusion imaging
Authors: Tran‐Gia Johannes , Lohr David , Weng Andreas Max , Ritter Christian Oliver , Stäb Daniel , Bley Thorsten Alexander , Köstler Herbert 
Published: September 2015

PurposeTo reduce saturation effects in the arterial input function (AIF) estimation of quantitative myocardial first‐pass saturation recovery perfusion imaging by employing a model‐based reconstruction.Theory and MethodsImaging was performed with a saturation recovery prepared radial FLASH sequence. A model‐based reconstruction was applied for reconstruction. By exploiting prior knowledge about the relaxation process, an image series with different saturation recovery times was reconstructed. By evaluating images with an effective saturation time of approximately 3 ms, saturation effects in the AIF determination were reduced. In a volunteer study, this approach was compared with a standard prebolus technique.ResultsIn comparison to the low‐dose injection of a prebolus acquisition, saturation effects were further reduced in the AIFs determined using the model‐based approach. These effects, which were clearly visible for all six volunteers, were reflected in a statistically significant difference of up to 20% in the absolute perfusion values.ConclusionThe application of model‐based reconstruction algorithms in quantitative myocardial perfusion imaging promises a significant improvement of the AIF determination. In addition to greatly reducing saturation effects that occur even for the prebolus methods, only a single bolus has to be applied. Magn Reson Med 76:880–887, 2016. © 2015 Wiley Periodicals, Inc.
Phased‐array combination for MR spectroscopic imaging using a water reference
Authors: Abdoli Abas , Maudsley Andrew A. 
Published: September 2015

PurposeTo evaluate methods for multichannel combination of three‐dimensional MR spectroscopic imaging (MRSI) data with a focus on using information from a water‐reference spectroscopic image.MethodsVolumetric MRSI data were acquired for a phantom and for human brain using 8‐ and 32‐channel detection. Acquisition included a water‐reference dataset that was used to determine the weights for several multichannel combination methods. Results were compared using the signal‐to‐noise ratio (SNR) of the N‐acetylaspartate resonance.ResultsPerformance of all methods was very similar for the phantom study, with the whitened singular value decomposition (WSVD) and signal magnitude (S) weighting combination having a small advantage. For in vivo studies, the S weighting, SNR weighting and signal to noise squared (S/N2) weighting were the three best methods and performed similarly. Example spectra and SNR maps indicated that the SVD and WSVD methods tend to fail for voxels at the outer edges of the brain that include strong lipid signal contributions.ConclusionFor data combination of MRSI data using water‐reference information, the S/N2 weighting, SNR and S weighting were the best methods in terms of spectral quality SNR. These methods are also computationally efficient and easy to implement. Magn Reson Med 76:733–741, 2016. © 2015 Wiley Periodicals, Inc.
Effect of Duodenal–Jejunal Bypass Surgery on Glycemic Control in Type 2 Diabetes: A Randomized Controlled Trial
Authors: Petry Tarissa Z. , Fabbrini Elisa , Otoch Jose P. , Carmona Murilo A. , Caravatto Pedro P. , Salles João E. , Sarian Thais , Correa Jose L. , Schiavon Carlos A. , Patterson Bruce W. , Cohen Ricardo , Klein Samuel 
Published: September 2015

ObjectiveTo determine whether upper gastrointestinal tract (UGI) bypass itself has beneficial effects on the factors involved in regulating glucose homeostasis in patients with type 2 diabetes (T2D).MethodsA 12‐month randomized controlled trial was conducted in 17 overweight/obese subjects with T2D, who received standard medical care (SC, n = 7, BMI = 31.7 ± 3.5 kg/m2) or duodenal–jejunal bypass surgery with minimal gastric resection (DJBm) (n = 10; BMI = 29.7 ± 1.9 kg/m2). A 5‐h modified oral glucose tolerance test was performed at baseline and at 1, 6, and 12 months after surgery or starting SC.ResultsBody weight decreased progressively after DJBm (7.9 ± 4.1%, 9.6 ± 4.2%, and 10.2 ± 4.3% at 1, 6, and 12 months, respectively) but remained stable in the SC group (P < 0.001). DJBm, but not SC, improved: (1) oral glucose tolerance (decreased 2‐h glucose concentration, P = 0.039), (2) insulin sensitivity (decreased homeostasis model assessment of insulin resistance, P = 0.013), (3) early insulin response to a glucose load (increased insulinogenic index, P = 0.022), and (4) overall glycemic control (reduction in HbA1c with fewer diabetes medications).ConclusionsDJBm causes moderate weight loss and improves metabolic function in T2D. However, our study cannot separate the benefits of moderate weight loss from the potential therapeutic effect of UGI tract bypass itself on the observed metabolic improvements.
Adenoma development in familial adenomatous polyposis and MUTYH‐associated polyposis: somatic landscape and driver genes
Authors: Rashid Mamunur , Fischer Andrej , Wilson Cathy H , Tiffen Jessamy , Rust Alistair G , Stevens Philip , Idziaszczyk Shelley , Maynard Julie , Williams Geraint T , Mustonen Ville , Sampson Julian R , Adams David J 
Published: September 2015

AbstractFamilial adenomatous polyposis (FAP) and MUTYH‐associated polyposis (MAP) are inherited disorders associated with multiple colorectal adenomas that lead to a very high risk of colorectal cancer. The somatic mutations that drive adenoma development in these conditions have not been investigated comprehensively. In this study we performed analysis of paired colorectal adenoma and normal tissue DNA from individuals with FAP or MAP, sequencing 14 adenoma whole exomes (eight MAP, six FAP), 55 adenoma targeted exomes (33 MAP, 22 FAP) and germline DNA from each patient, and a further 63 adenomas by capillary sequencing (41 FAP, 22 MAP). With these data we examined the profile of mutated genes, the mutational signatures and the somatic mutation rates, observing significant diversity in the constellations of mutated driver genes in different adenomas, and loss‐of‐function mutations in WTX (9%; p < 9.99e‐06), a gene implicated in regulation of the WNT pathway and p53 acetylation. These data extend our understanding of the early events in colorectal tumourigenesis in the polyposis syndromes. © 2015 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Non‐ and semipolar AlInN one‐dimensionally lattice‐matched to GaN for realization of relaxed buffer layers for strain engineering in optically active GaN‐based devices
Authors: Buß E. R. , Horenburg P. , Rossow U. , Bremers H. , Meisch T. , Caliebe M. , Scholz F. , Hangleiter A. 
Published: September 2015

AbstractIn this contribution, we demonstrate that for non‐ and semipolar AlInN one‐dimensionally lattice‐matched to GaN, controlled relaxation in different in‐plane directions of the growth surface can be induced. All of our samples were grown on GaN templates on patterned r‐plane sapphire as well as on m‐oriented 6H‐SiC substrates and free‐standing pseudo‐bulk GaN substrates. The InN mole fraction of the AlInN is varied from 18% up to 28% corresponding to one‐dimensional lattice matching in various in‐plane directions of the growth surface. By controlling the composition as well as the thickness, we realized one‐dimensional relaxation of the AlInN layers along the nonlattice‐matched direction. This opens new perspectives for strain and polarization engineering in optically active layers grown subsequently and gives new possibilities to design high indium‐containing GaInN quantum well structures for efficient long wavelength light emitters.
Idealized simulations of the effect of Taiwan topography on the tracks of tropical cyclones with different sizes
Authors: Tang Chi Kit , Chan Johnny C. L. 
Published: September 2015

This is the third part of a study of the effect of topography on tropical cyclone (TC) tracks. In previous parts, idealized simulations were conducted using the Weather Research and Forecasting model to study the underlying mechanisms for the upstream northward deflection of a TC and the effects of local and remote topography. The initial TC size was the same in all these simulations. In this third part, the track deflections of TCs with different sizes are investigated. As in the two earlier parts, the simulations are made on a beta plane with no background flow.For a TC approaching Taiwan, there is an apparent optimal TC size with the largest northward deflection. However, an appreciable track deflection is only found for smaller TCs approaching Taiwan directly. In addition, as might be expected, the onset location of the northward deflection is closer to Taiwan for smaller TCs. Moreover, the contribution from diabatic heating is opposite to that from horizontal advection (HA) in the potential vorticity tendency (PVT) calculation due to the vertical wind shear induced by the terrain‐induced gyres although HA is still the dominant term in the PVT equation.A southward deflection on the eastern side of Taiwan is found in some smaller TC cases. A looping track occurs for a medium‐size TC approaching central Taiwan and a V‐shape track is found for a small‐size TC approaching northern Taiwan. Among the cases, some similarities can be found. First, the gyre flow becomes weak so that the TC is slowed down. Second, an individual cyclonic gyre is found on the southeastern side of Taiwan so that the TC is deflected westward and then southward. Third, another newly generated gyre pair pushes the TC northward after the southward deflection.
On the Computation of Powers of Sparse Polynomials
Authors: Fateman Richard J. 
Published: September 2015

This paper examines the time for computing integer powers of a class of polynomials in one or several variables. A member f of the class of “sparse” polynomials can be characterized by the number of nonzero terms, t, in the representation of f. Where, for power 4, the most obvious methods result in

multiplications, a method is presented which requires fewer than

multiplications.This algorithm requires, for t » n » 1 about tn/n! + O(tn − 1 /(2(n − 2)!)) multiplications, which is proved to be a lower‐bound on the computation.