bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnetic Nanoclusters Engineered by Polymer‐Controlled Self‐Assembly for the Accurate Diagnosis of Atherosclerotic Plaques via Magnetic Resonance Imaging
Authors: Kim Myeong‐Hoon , Kim Bongjune , Lim Eun‐Kyung , Choi Yuna , Choi Jihye , Kim Eunjung , Jang Eunji , Park Hyo Seon , Suh Jin‐Suck , Huh Yong‐Min , Haam Seungjoo 
Published: April 2014

AbstractOleyl dextran‐coated magnetic nanoclusters (ODMCs) are fabricated for the accurate detection of macrophage‐rich atherosclerotic plaques using magnetic resonance (MR) imaging. Dextran is introduced to the cluster surface of magnetic nanocrystals (MNCs) through self‐assembly using amphiphilic oleic acid‐conjugated dextran (ODex) to provide not only hydrophilicity but also a high affinity to macrophages. Enhanced magnetism of the ODMCs is engineered by optimizing the degree of substitution (DS) of the oleyl group in ODex and the concentration of ODex used for the synthesis of ODMC. Consequently, ODMCs exhibit significantly increased T2 relaxivity and excellent macrophage‐targeting ability without cytotoxicity, in vitro. Moreover, in vivo T2‐weighted MR imaging after intravenous injection of ODMCs into a rat artery balloon injury model demonstrates considerable MR contrast strength efficacy in the plaques of the injured carotid artery. These novel ODMCs may offer a highly efficient MR imaging nanoprobes for the selective diagnosis of atherosclerosis.
Morphing Hydrogel Patterns by Thermo‐Reversible Fluorescence Switching
Authors: Bat Erhan , Lin En‐Wei , Saxer Sina , Maynard Heather D. 
Published: April 2014

Stimuli responsive surfaces that show reversible fluorescence switching behavior in response to temperature changes were fabricated. Oligo(ethylene glycol) methacrylate thermoresponsive polymers with amine end‐groups were prepared by atom transfer radical polymerization (ATRP). The polymers were patterned on silicon surfaces by electron beam (e‐beam) lithography, followed by conjugation of self‐quenching fluorophores. Fluorophore conjugated hydrogel thin films were bright when the gels were swollen; upon temperature‐induced collapse of the gels, self‐quenching of the fluorophores led to significant attenuation of fluorescence. Importantly, the fluorescence was regained when the temperature was cooled. The fluorescence switching behavior of the hydrogels for up to ten cycles was investigated and the swelling‐collapse was verified by atomic force microscopy. Morphing surfaces that change shape several times upon increase in temperature were obtained by patterning multiple stimuli responsive polymers.
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Gut feelings about smoking and coffee in Parkinson's disease
Authors: Derkinderen Pascal , Shannon Kathleen M , Brundin Patrik 
Published: April 2014

ABSTRACTStrong epidemiologic evidence suggests that smokers and coffee drinkers have a lower risk of Parkinson's disease (PD). The explanation for this finding is still unknown, and the discussion has focused on two main hypotheses. The first suggests that PD patients have premorbid personality traits associated with dislike for coffee‐drinking and smoking. The second posits that caffeine and nicotine are neuroprotective. We propose an alternative third hypothesis, in which both cigarette and coffee consumption change the composition of the microbiota in the gut in a way that mitigates intestinal inflammation. This, in turn, would lead to less misfolding of the protein alpha‐synuclein in enteric nerves, reducing the risk of PD by minimizing propagation of the protein aggregates to the central nervous system, where they otherwise can induce neurodegeneration. © 2014 International Parkinson and Movement Disorder Society
Urinary metabolite profiling identifies novel colonic metabolites and conjugates of phenolics in healthy volunteers
Authors: Pimpão Rui C. , Dew Tristan , Figueira Maria E. , McDougall Gordon J. , Stewart Derek , Ferreira Ricardo B. , Santos Claudia N. , Williamson Gary 
Published: April 2014

ScopeThe colonic metabolism of dietary flavonoids, phenolic acids and their phenolic metabolites is complex and many metabolites and conjugates have not yet been unambiguously identified in humans.Methods and resultsUrine samples from nine healthy human volunteers obtained after the ingestion of a puree of five (poly)phenol‐rich berry fruits were analysed using LC‐Orbitrap MS to provide a preliminary indication of possible metabolites based on exact mass. In most cases, the identity of compounds was confirmed using standards produced either chemically or enzymically followed by analysis using LC‐triple quadrupole MS. Sulphated, glucuronidated and methylated forms of catechol, pyrogallol and protocatechuic acid mostly appeared in urine after 8 h, suggesting colonic metabolism. Gallic acid and (−)‐epicatechin conjugates appeared mainly before 4 h, indicative of absorption from the small intestine. Conjugates of ferulic, caffeic, and vanillic acid appeared at intermediate times.ConclusionWe have positively identified metabolites and conjugates, some novel, in the urine of healthy volunteers after intake of multiple phenolics from a mixed puree from berry fruits, with each being excreted at specific and signature times. Some of these compounds could potentially be used as biomarkers of fruit intake. The possible biological activities of these colonic metabolites require further assessment.
A randomized comparative effectiveness trial of using cable television to deliver diabetes prevention programming
Authors: Ackermann Ronald T. , Sandy Lewis G. , Beauregard Tom , Coblitz Mark , Norton Kristi L. , Vojta Deneen 
Published: April 2014

ObjectiveTo evaluate the use and effectiveness of two “in‐home” strategies for delivering diabetes prevention programming using cable television.MethodsAn individually randomized, two‐arm intervention trial including adults with diabetes risk factors living in two US cities. Interventions involved a 16‐session lifestyle intervention delivered via “video‐on‐demand” cable television, offered alone versus in combination with web‐based lifestyle support tools. Repeated measures longitudinal linear regression with imputation of missing observations was used to compare changes in body weight.ResultsA total of 306 individuals were randomized and offered the interventions. After 5 months, 265 (87%) participants viewed at least 1, and 110 (36%) viewed ≥9 of the video episodes. A total of 262 (86%) participants completed a 5‐month weight measurement. In intention‐to‐treat analysis with imputation of missing observations, mean weight loss at 5 months for both treatment groups combined was 3.3% (95% CI 0.7‐5.0%), regardless of intervention participation (with no differences between randomized groups (P = 0.19)), and was 4.9% (95% CI 2.1‐6.5%) for participants who viewed ≥9 episodes.ConclusionsIn‐home delivery of evidence‐based diabetes prevention programming in a reality television format, offered with or without online behavioral support tools, can achieve modest weight losses consistent with past implementation studies of face‐to‐face programs using similar content.
NLRPs, microbiota, and gut homeostasis: unravelling the connection
Authors: Zambetti Lia Paola , Mortellaro Alessandra 
Published: April 2014

AbstractWithin the NOD‐like receptor (NLR) family, there are several NLRP (NLR family, pyrin domain‐containing) proteins that are involved in the formation of inflammasomes. These multi‐protein complexes are a key part of the network of cellular events required for secretion of the pro‐inflammatory cytokines IL‐1β and IL‐18. The NLRP3 inflammasome is the best‐characterized member of the family and has recently been implicated in gut homeostasis and determining the severity of inflammation in inflammatory bowel disease (IBD) and inflammation‐associated colorectal cancer. This led to the discovery that NLRP6 and NLRP12 also contribute to the maintenance of intestinal homeostasis and modulation of the gut microbiota, which in turn influences the intestine and distant organs. In this review, we bring together the latest data on the potential roles of NLRP family members in gut health and disease and identify the most pressing questions that remain to be answered to further our understanding of human diseases including IBD, inflammation‐associated cancers, and metabolic syndromes linked with obesity. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Guideline for the prevention and treatment of anticipatory nausea and vomiting due to chemotherapy in pediatric cancer patients
Authors: Dupuis L. Lee , Robinson Paula D. , Boodhan Sabrina , Holdsworth Mark , Portwine Carol , Gibson Paul , Phillips Robert , Maan Cathy , Stefin Nancy , Sung Lillian 
Published: April 2014

ABSTRACTThis guideline provides an approach to the prevention and treatment of anticipatory chemotherapy‐induced nausea and vomiting (CINV) in children. It was developed by an international, inter‐professional panel using AGREE II methods and is based on systematic literature reviews. Evidence‐based recommendations for pharmacological and non‐pharmacological interventions to prevent and treat anticipatory CINV in children receiving antineoplastic agents are provided. Gaps in the evidence used to support the recommendations are identified. The contribution of this guideline to anticipatory CINV control in children requires prospective evaluation. Pediatr Blood Cancer 2014; 61:1506–1512. © 2014 Wiley Periodicals, Inc.
Anti‐gastroesophageal reflux surgery in infants with severe bronchopulmonary dysplasia
Authors: Jensen Erik A. , Munson David A. , Zhang Huayan , Blinman Thane A. , Kirpalani Haresh 
Published: April 2014

SummaryGastroesophageal reflux may exacerbate lung disease in infants with bronchopulmonary dysplasia (BPD). Anti‐reflux surgery may therefore reduce the severity of this disease in some infants. We report a retrospective series of 22 infants with severe BPD who underwent anti‐reflux surgery. Our experience indicates that these procedures can be safely performed in this population and that early post‐operative initiation of gastric feeds is well tolerated. Modest post‐operative reductions in required oxygen and median respiratory rate were observed. Pediatr Pulmonol. 2015; 50:584–587. © 2014 Wiley Periodicals, Inc.
Effects of a non‐absorbing substrate on the magneto‐optical Kerr response of plasmonic ferromagnetic nanodisks
Authors: Maccaferri Nicolò , Kataja Mikko , Bonanni Valentina , Bonetti Stefano , Pirzadeh Zhaleh , Dmitriev Alexandre , van Dijken Sebastiaan , Åkerman Johan , Vavassori Paolo 
Published: April 2014

Magnetoplasmonics is an emerging field of intense research on materials combining magnetic and plasmonic functionalities. The novel optical and magneto‐optical (MO) properties displayed by these materials could allow the design of a new class of magnetically controllable optical nano‐devices. In this work, we investigate the effects of a non‐absorbing (insulating) substrate on the MO activity of pure ferromagnetic disk‐shaped nanostructures supporting localized plasmon resonances. We show that the red‐shift of the localized plasmon resonance, related to the modification of the localization of the electromagnetic field due to the substrate, is not the only effect that the substrate has on the MO response. We demonstrate that the reflectivity of the substrate itself plays a key role in determining the MO response of the system. We discuss why it is so and provide a description of the modeling tools suitable to take into account both effects. Understanding the role of the substrate will permit a more aware design of magnetoplasmonic nanostructured devices for future biotechnological and optoelectronic applications. Ferromagnetic nickel nanodisk in vacuum (left) and on a non‐absorbing substrate (right), illuminated by linearly polarized light. The polarization of the reflected field is changed in the first case due to a combination of intrinsic magneto‐optical properties and the nanoconfinement of the material. In the second case, the polarization of the reflected light is affected also by the presence of the substrate.
Investigation of hidden periodic structures on SEM images of opal‐like materials using FFT and IFFT
Authors: Stephant Nicolas , Rondeau Benjamin , Gauthier Jean‐Pierre , Cody Jason A. , Fritsch Emmanuel 
Published: April 2014

SummaryWe have developed a method to use fast Fourier transformation (FFT) and inverse fast Fourier transformation (IFFT) to investigate hidden periodic structures on SEM images. We focused on samples of natural, play‐of‐color opals that diffract visible light and hence are periodically structured. Conventional sample preparation by hydrofluoric acid etch was not used; untreated, freshly broken surfaces were examined at low magnification relative to the expected period of the structural features, and, the SEM was adjusted to get a very high number of pixels in the images. These SEM images were treated by software to calculate autocorrelation, FFT, and IFFT. We present how we adjusted SEM acquisition parameters for best results. We first applied our procedure on an SEM image on which the structure was obvious. Then, we applied the same procedure on a sample that must contain a periodic structure because it diffracts visible light, but on which no structure was visible on the SEM image. In both cases, we obtained clearly periodic patterns that allowed measurements of structural parameters. We also investigated how the irregularly broken surface interfered with the periodic structure to produce additional periodicity. We tested the limits of our methodology with the help of simulated images. SCANNING 36:487–499, 2014. © 2014 Wiley Periodicals, Inc.
Problematizing the STEM Pipeline Metaphor: Is the STEM Pipeline Metaphor Serving Our Students and the STEM Workforce?
Authors: CANNADY MATTHEW A. , GREENWALD ERIC , HARRIS KIMBERLY N. 
Published: April 2014

ABSTRACTResearchers and policy makers often use the metaphor of an ever‐narrowing pipeline to describe the trajectory to a science, technology, engineering or mathematics (STEM) degree or career. This study interrogates the appropriateness of the STEM pipeline as the dominant frame for understanding and making policies related to STEM career trajectories. Our review of pertinent literature and independent analysis of data from the National Educational Longitudinal Study of 1988 finds that the trajectory implied by the pipeline metaphor fails to describe the experience for nearly half of those who go on to become scientists or engineers, masks meaningful differences in trajectories by subfield, and informs policies that do little to diversify or increase the size of the STEM workforce. We suggest a pathway metaphor to better illuminate the multiple trajectories toward STEM degrees and careers and present four composite trajectories as useful categorizations of the individual paths taken by STEM graduates and career entrants.
Understanding the Heterogeneous Nature of Science: A Comprehensive Notion of PCK for Scientific Literacy
Authors: VAN DIJK ESTHER M. 
Published: April 2014

ABSTRACTThis paper is concerned with the conceptualization of pedagogical content knowledge (PCK) for teaching about the nature of science. In contrast to the view that science teachers need to develop a specific “PCK for nature of science,” an alternative, more comprehensive notion of PCK for science teaching is suggested. The point of departure for the development of this notion is Shulman's original conceptualization of PCK that is rooted in Schwab's views of science. With respect to the aim of science teaching to enhance scientific literacy, this approach may offer science teachers an appropriate way to portray and reflect on the diversity of scientific practices within their teaching. In addition, the different interpretations of the “nature of science” and “inquiry” that both feature prominently in Schwab's work and in contemporary discussions of the nature of science are discussed.
Examining Classroom Science Practice Communities: How Teachers and Students Negotiate Epistemic Agency and Learn Science‐as‐Practice
Authors: STROUPE DAVID 
Published: April 2014

ABSTRACTThe Next Generation Science Standards and other reforms call for students to learn science‐as‐practice, which I argue requires students to become epistemic agents—shaping the knowledge and practice of a science community. I examined a framework for teaching—ambitious instruction—that scaffolds students’ learning of science‐as‐practice as they act as epistemic agents. Using a situative theoretical framework and analytical tools from science studies literature, I conducted a multicase study of five beginning teachers. I found that (a) teachers and students negotiated their roles as they decided on “what counted” as science ideas. Participants positioned some ideas as important by making discursive moves, signaling students to either work on the ideas as epistemic agents or, alternatively, to judge the information as “right” or “wrong”; (b) the participants worked to make science a “public” or “private” enterprise. The framing of science then influenced how teachers and students participated in their science practice community; (c) the negotiation of “what counted” as science ideas and the framing of science as “public” or “private” influenced (i) the percentage of students sharing ideas on the public plane, and (ii) the number of science ideas initiated and kept in play on the public plane.
Punching shear design of footings: critical review of different code provisions
Authors: Siburg Carsten , Ricker Marcus , Hegger Josef 
Published: April 2014

AbstractEurocode 2 and the corresponding National Annex were introduced in Germany in 2012. Most of the design provisions for these new standards were adopted from Model Code 1990 and provide a new design approach for ground slabs and footings. For the fib Model Code for Concrete Structures 2010, the punching shear design concept has been revised and introduced in Swiss standard SIA262:2013. This paper presents in detail the design equations for determining the punching capacity according to Eurocode 2, the German National Annex to Eurocode 2, fib Model Code 2010 and SIA 262:2013.Parametric studies have been used to examine the influence of the main parameters (shear span‐depth ratio, effective depth, longitudinal reinforcement ratio and concrete compressive strength) on the punching shear resistance of footings. To quantify the level of safety and the efficiency, the design provisions are compared with systematic test series.
Surgeon practices regarding infection prevention for growth friendly spinal procedures
Authors: Glotzbecker Michael P. , Garg Sumeet , Akbarnia Behrooz A. , Vitale Michael , Hillaire Tricia St , Joshi Ajeya 
Published: April 2014

Purpose The rate of infection in patients having growth sparing surgery for early onset scoliosis has been reported up to 25 % during the course of treatment. A recent study demonstrated significant variability in the approach to infection prevention in adolescent and neuromuscular scoliosis. The purpose of this study is to conduct a similar survey in order to understand approaches used by experienced pediatric spinal surgeons with regard to infection prevention in growth friendly spinal procedures. Materials and methods After preliminary internal testing of a survey by the authors, a final 21-question survey was created and approved by the authors and electronically distributed to all members of the Chest Wall Spinal Deformity Study Group and the Growing Spine Study Group ( n = 57). A total of 40 responses were obtained (70 %). Results Significant variability in practice was demonstrated across the majority of the questions answered. Several of the questions demonstrated relative equipoise between practices, including preoperative MRSA screening, preoperative chlorhexidine baths, postoperative antibiotic duration after insertion, use of topical antibiotics, use of drains, use of IV gram negative coverage or vancomycin, and skin preparation. Conclusion Other studies have demonstrated that variability in practice may have a negative impact on clinical outcomes, so one could postulate that steps that can reduce variability in the current population may help improve outcomes in this population. Areas of clinical equipoise can be used to help design and direct multicenter studies with an ultimate goal of reducing infections in this population. Level of evidence Level V.
Modelling the dynamics of a sphere approaching and bouncing on a wall in a viscous fluid
Authors: Izard Edouard , Bonometti Thomas , Lacaze Laurent 
Published: April 2014

AbstractThe canonical configuration of a solid particle bouncing on a wall in a viscous fluid is considered here, focusing on rough particles as encountered in most of the laboratory experiments or applications. In that case, the particle deformation is not expected to be significant prior to solid contact. An immersed boundary method (IBM) allowing the fluid flow around the solid particle to be numerically described is combined with a discrete element method (DEM) in order to numerically investigate the dynamics of the system. Particular attention is paid to modelling the lubrication force added in the discrete element method, which is not captured by the fluid solver at very small scale. Specifically, the proposed numerical model accounts for the surface roughness of real particles through an effective roughness length in the contact model, and considers that the time scale of the contact is small compared to that of the fluid. The present coupled method is shown to quantitatively reproduce available experimental data and in particular is in very good agreement with recent measurement of the dynamics of a particle approaching very close to a wall in the viscous regime $St \le {O}(10)$, where $St$ is the Stokes number which represents the balance between particle inertia and viscous dissipation. Finally, based on the reliability of the numerical results, two predictive models are proposed, namely for the dynamics of the particle close to the wall and the effective coefficient of restitution. Both models use the effective roughness height and assume the particle remains rigid prior to solid contact. They are shown to be pertinent to describe experimental and numerical data for the whole range of investigated parameters.
Linear instability analysis of convection in a laterally heated cylinder
Authors: Wang Bo-Fu , Wan Zhen-Hua , Guo Zhi-Wei , Ma Dong-Jun , Sun De-Jun 
Published: April 2014

AbstractThe three-dimensional instabilities of axisymmetric flow are investigated in a laterally heated vertical cylinder by linear stability analysis. Heating is confined to a central zone on the sidewall of the cylinder, while other parts of the sidewall are insulated and both ends of the cylinder are cooled. The length of the heated zone equals the radius of the cylinder. For three different aspect ratios, $A= 1.92 $, 2, 2.1 ($A=\mathrm{height}$/radius), the dependence of the critical Rayleigh number on the Prandtl number (from 0.02 to 6.7) has been studied in detail. For such a kind of laterally heated convection, some interesting stability results are obtained. A monotonous instability curve is obtained for $A= 1.92 $, while the instability curves for $A= 2 $ and $A= 2.1 $ are non-monotonous and multivalued. In particular, an instability island has been found for $A=2$. Moreover, mechanisms corresponding to different instability results are obtained when the Prandtl number changes. At small Prandtl number, the flow is oscillatory unstable, which is dominated by hydrodynamic instability. At intermediate Prandtl number, the interaction between buoyancy and shear in the base flow plays a more important role than pure hydrodynamic instability. At even higher Prandtl number, Rayleigh–Bénard instability becomes the dominant process and the flow loses stability through steady bifurcation.