bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of Langmuir Films Prepared from Copolyesterurethanes Based on Oligo(ω‐pentadecalactone) and Oligo(ε‐caprolactone) Segments
Authors: Schöne Anne‐Christin , Schulz Burkhard , Richau Klaus , Kratz Karl , Lendlein Andreas 
Published: October 2014

A series of multiblock copolymers (PDLCL) synthesized from oligo(ω‐pentadecalactone)diol (OPDL) and oligo(ε‐caprolactone)diol (OCL), which are linked by 2,2(4),4‐trimethyl‐hexa­methylene diisocyanate (TMDI), is investigated by the Langmuir monolayer technique at the air–water interface. Brewster angle microscopy (BAM) and spectroscopic ellipsometry are employed to characterize the polymer film morphologies in situ. PDLCL containing ≥40 wt% OCL segments form homogeneous Langmuir monofilms after spreading. The film elasticity modulus decreases with increasing amounts of OPDL segments in the copolymer. In contrast, the OCL‐free polyesterurethane OPDL‐TMDI cannot be spread to monomolecular films on the water surface properly, and movable slabs are observed by BAM even at low surface pressures. The results of the in situ morphological characterization clearly show that essential information concerning the reliability of Langmuir monolayer degradation (LMD) experiments cannot be obtained from the evaluation of the π–A isotherms only. Consequently, in situ morphological characterization turns out to be indispensable for characterization of Langmuir layers before LMD experiments.
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Kinetics of Magnetic Field‐Induced Orientational Ordering in Block Copolymer/Superparamagnetic Nanoparticle Composites
Authors: Raman Vinay , Hatton T. Alan , Olsen Bradley D. 
Published: October 2014

The combination of external potential dynamics and Brownian dynamics is introduced to study the kinetics of orientational ordering in block copolymer/superparamagnetic nanoparticle composites where the particles are smaller than the domain spacing and preferentially segregate into one block of the copolymer. This simulation method accounts for both excluded volume interactions and dipolar interactions between particles to quantify alignment kinetics. Two‐dimensional simulations reveal that higher dipolar interaction strengths lead to faster alignment of the block copolymer, where the orientation kinetics obeys an exponential rate law. The observed rate of alignment increases with increasing dipolar interaction strength and is dependent on the initial state of the block copolymer. The primary mechanism of orientational ordering is found to be the redistribution of monomer segments leading to bridging and growth of the block copolymer domains around the nanoparticles.
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Growth of White Rot Fungi in Composites Produced from Urban Plastic Waste and Wood
Authors: Catto André Luis , Rosseto Eduardo Soares , Reck Mateus Arduvino , Rossini Katiandry , da Silveira Rosa Mara Borges , Santana Ruth Marlene Campomanes 
Published: October 2014

SummaryIn the search for new biodegradable materials is found the combination of natural fibers with conventional polymeric materials or biodegradable polymers. The incorporation of natural fibers to thermoplastic polymer matrix is associated with improvement of their properties due to advantages such as the fact that the natural fibers are biodegradable and less abrasive when compared to synthetic fibers. The materials produced with conventional synthetic polymers are considered inert to immediate attack of microorganisms, as thermoplastic polymers used in this research, PP (polypropylene) and EVA (ethylene vinyl acetate). Thus, this study aims to evaluate the potential for biodegradation of wood plastic composites (WPC) obtained through the use of post‐consumer bottle caps and wood flour. The monitoring was conducted through cultivation of different species of fungi (basidiomycetes) on different substrates, being made by gravimetric analysis and visual monitoring of the composites, in order to assess that species of fungus has increased growth kinetics and its relation with different kinds of wood and then have an estimate of the potential biotic degradation of these materials. Based on results presented here, it is concluded that the Trametes villosa (TV) fungi is that best interacted with the wood contained in the composite in both species of Eucalyptus grandis (Eu) as Pinus elliottii (Pi).
Abnormalities of Masseteric Inhibitory Reflex in Hereditary Geniospasm: Evidence for a Brainstem Myoclonus
Authors: Macerollo Antonella , Saifee Tabish A. , Kassavetis Panagiotis , Pilurzi Giovanna , Schneider Susanne A. , Edwards Mark J. , Bhatia Kailash P. 
Published: October 2014

AbstractWe studied two unrelated families with several members suffering from geniospasm. Here, we aim to clarify the pathophysiology underlying the hereditary geniospasm through testing of brainstem excitability by the recovery cycles of the blink reflex (BR) and the masseteric inhibitory reflex (MIR). The R2 component of the BR and the SP2 component of the MIR and their recovery cycle were analyzed in 3 patients and 8 healthy, age‐matched subjects as the control group. Patients with geniospasm exhibited a different excitability of the BR, compared to the control, group, as shown by the larger R2 component area of BR in controls than patients. Notably, the mean recovery index was 0.61 ± 0.19 in geniospasm patients and 0.40 ± 0.15 in controls (P ≤ 0.05). Interestingly, the recovery cycle of the MIR showed a loss of inhibition in both patients studied, as indicated by the behavior of the SP2 component. Our cases showed a partial impairment of the activity of brainstem inhibitory interneurons, indicated by the abnormal recovery cycle of MIR. These results would implicate a mechanism akin to brainstem myoclonus for the generation of geniospasm.
Fast spin echo imaging of carotid artery dynamics
Authors: Boesen Mari E. , Maior Neto Luis A. Souto , Pulwicki Alexandra , Yerly Jerome , Lebel R. Marc , Frayne Richard 
Published: October 2014

PurposeWe propose the use of a retrospectively gated cine fast spin echo (FSE) sequence for characterization of carotid artery dynamics. The aim of this study was to compare cine FSE measures of carotid dynamics with measures obtained on prospectively gated FSE images.MethodsThe common carotid arteries in 10 volunteers were imaged using two temporally resolved sequences: (i) cine FSE and (ii) prospectively gated FSE. Three raters manually traced a common carotid artery area for all cardiac phases on both sequences. Measured areas and systolic–diastolic area changes were calculated and compared. Inter‐ and intra‐rater reliability were assessed for both sequences.ResultsNo significant difference between cine FSE and prospectively gated FSE areas were observed (P = 0.36). Both sequences produced repeatable cross‐sectional area measurements: inter‐rater intraclass correlation coefficient (ICC) = 0.88 on cine FSE images and 0.87 on prospectively gated FSE images. Minimum detectable difference (MDD) in systolic–diastolic area was 4.9 mm2 with cine FSE and 6.4 mm2 with prospectively gated FSE.ConclusionThis cine FSE method produced repeatable dynamic carotid artery measurements with less artifact and greater temporal efficiency compared with prospectively gated FSE. Magn Reson Med 74:1103–1109, 2015. © 2014 Wiley Periodicals, Inc.
Retrobulbar magnetic resonance angiography using binomial off‐resonant rectangular (BORR) pulse
Authors: Ye Yongquan , Wu Zhen , Lewis Nicholas A. , Fan Qingxia , Haacke E. Mark 
Published: October 2014

PurposeApplying a newly developed binomial off‐resonant rectangular (BORR) pulse method for high resolution three‐dimensional MR angiography (MRA) on retrobulbar ocular vessels, which has not been possible with routine MRA due to background fatty tissues.MethodsBORR pulse was implemented in a gradient echo sequence by replacing the original excitation pulse, and were optimized for robust orbital fat suppression. Several other MRA methods, with or without fat suppression, were also compared, including time‐of‐flight, contrast enhanced MRA, and hybrid of opposite‐contrast MRA. Nine healthy subjects participated with written informed consents. To reduce eye motion, the subjects were instructed to casually stare at a projected cross during each MRA scan. Major vessels were evaluated by three independent radiologists using a 4‐point scale.ResultsThe BORR method yielded the best MRA results for retrobulbar vessels without contrast enhancement, significantly superior than other MRA methods. BORR results had significantly higher visibility scores than all other methods for small vessels.ConclusionWe have successfully revealed orbital vessels in retrobulbar space for the first time using MRA, by using the BORR pulse method. With a clear depiction of the vasculature without the need for contrast enhancement, our method has the potential to provide important diagnostic information for ocular vascular diseases. Magn Reson Med 74:1050–1056, 2015. © 2014 Wiley Periodicals, Inc.
A numerical study of the influence from pre‐existing cracks on granite rock fragmentation at percussive drilling
Authors: Saadati Mahdi , Forquin Pascal , Weddfelt Kenneth , Larsson Per‐Lennart , Hild Francois 
Published: October 2014

SummaryThe aim of this study is to investigate the effect of pre‐existing, or structural, cracks on dynamic fragmentation of granite. Because of the complex behavior of rock materials, a continuum approach is employed relying upon a plasticity model with yield surface locus as a quadratic function of the mean pressure in the principal stress space coupled with an anisotropic damage model. In particular, Bohus granite rock is investigated, and the material parameters are chosen based on previous experiments. The equation of motion is discretized using a finite element approach, and the explicit time integration method is employed. The pre‐existing cracks are introduced in the model by considering sets of elements with negligible tensile strength that leads to their immediate failure when loaded in tension even though they still carry compressive loads as crack closure occurs because of compressive stresses. Previously performed edge‐on impact tests are reconsidered here to validate the numerical model. Percussive drilling is simulated, and the influence of the presence of pre‐existing cracks is studied. The results from the analysis with different crack lengths and orientations are compared in terms of penetration stiffness and fracture pattern. It is shown that pre‐existing cracks in all investigated cases facilitate the drilling process. Copyright © 2014 John Wiley & Sons, Ltd.
Anodic Stripping Voltammetry of Silver Nanoparticles: Aggregation Leads to Incomplete Stripping
Authors: Cloake Samantha J. , Toh Her Shuang , Lee Patricia T. , Salter Chris , Johnston Colin , Compton Richard G. 
Published: October 2014

AbstractThe influence of nanoparticle aggregation on anodic stripping voltammetry is reported. Dopamine‐capped silver nanoparticles were chosen as a model system, and melamine was used to induce aggregation in the nanoparticles. Through the anodic stripping of the silver nanoparticles that were aggregated to different extents, it was found that the peak area of the oxidative signal corresponding to the stripping of silver to silver(I) ions decreases with increasing aggregation. Aggregation causes incomplete stripping of the silver nanoparticles. Two possible mechanisms of ‘partial oxidation’ and ‘inactivation’ of the nanoparticles are proposed to account for this finding. Aggregation effects must be considered when anodic stripping voltammetry is used for nanoparticle detection and quantification. Hence, drop casting, which is known to lead to aggregation, is not encouraged for preparing electrodes for analytical purposes.
Bildqualität ist nicht alles
Authors: Konopka Bernd 
Published: October 2014

AbstractKameras für Anwendungen in der Videoüberwachung müssen nicht nur qualitativ hochwertige Bilder liefern, sondern auch eine effiziente Übertragung und Speicherung dieser Bilder erlauben. Ein wesentliches Kriterium ist daher die eigene Intelligenz der Kamera, mit der sich dynamisch zu jedem Zeitpunkt die beste Balance aus Dateigröße und Bildqualität finden lässt.
Gute Aussichten für die Photonik
Authors: Löffler Annika 
Published: October 2014

AbstractDie Schlüsseltechnologie Photonik blickt positiv in die Zukunft: bis zum Jahr 2020 soll das Weltmarktvolumen des Technologiefelds auf rund 615 Milliarden Euro ansteigen, wie die Branchenfachverbände VDMA, Spectaris und ZVEI sowie das Bundesministerium für Bildung und Forschung BMBF im 2013 erstmals vorgestellten „Branchenreport Photonik”︁ erwarten. Dies entspricht einem durchschnittlichen jährlichen Wachstum mindestens anderthalb Mal so hoch wie das Wachstum des weltweiten Bruttoinlandsprodukts, basierend auf einem unterstellten Weltmarktvolumen von rund 350 Milliarden Euro in 2011.
Janus hybrid hairy nanoparticles
Authors: Zhou Tian , Dong Bin , Qi Hao , Mei Shan , Li Christopher Y. 
Published: October 2014

ABSTRACTJanus hairy nanoparticles (JHNPs) represent a new class of hybrid materials with a nanoparticle core and a layer of bicompartmentalized polymer brushes. This unique structure combines the complex properties of polymer brushes, the amphiphilic nature of surfactant, and the mechanical, optical, and electronic properties of nanoparticles. Over the past decade, tremendous efforts have been devoted to synthesizing JHNPs and understanding their structure and properties. In this review, we will summarize the recent progresses in the field, including fabrication approaches and the self‐ and directed assembly behavior of such JHNPs. We will specifically focus on the newly developed polymer single crystal directed nanoparticle assembly approach. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1620–1640
Organic‐inorganic nanocomposites composed of conjugated polymers and semiconductor nanocrystals for photovoltaics
Authors: Jung Jaehan , Yoon Young Jun , He Ming , Lin Zhiqun 
Published: October 2014

ABSTRACTSemiconductor organic‐inorganic nanocomposites have garnered much attention as they integrate the advantageous properties from conjugated polymers (CPs) and semiconductor nanocrystals (NCs). Recent developments in interfacial engineering of CP‐NC nanocomposites enabled the intimate contact between CPs and NCs, thereby facilitating charge separation between these two constituents. To capitalize on the use of CP‐NC nanocomposites for hybrid solar cells, several issues need to be addressed, including materials design and engineering, light harvesting, and morphology of photoactive layer. In this Review, the general working principle of hybrid solar cells and the development of p‐type and n‐type CPs are briefly introduced, followed by the highlight of recent advances in synthesis of CP‐NC nanocomposites in which CP and NC are in intimate contact for hybrid solar cells, and the discussion on various strategies for potentially improved power conversion efficiency. An outlook for future directions in this area is also presented. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1641–1660
Effect of Vegetation Cover on the Ground Thermal Regime of Wooded and Non‐Wooded Palsas
Authors: Jean Mélanie , Payette Serge 
Published: October 2014

ABSTRACTAlthough warming air temperatures are contributing to permafrost degradation across the circumpolar zone, understanding of permafrost and environmental feedbacks to climate change is limited. Palsas can be used as indicators of permafrost stability given their sensitivity to changes in temperature and precipitation. However, field observations on the effects of vegetation cover are needed to compare permafrost dynamics of wooded and non‐wooded palsas. This study examined the influence of vegetation on the soil thermal regime of wooded palsas covered by black spruce trees and non‐wooded palsas covered by shrubs in discontinuous permafrost of the Boniface River area of northern Quebec, Canada. It investigated the effects of organic layer thickness, vegetation and snow depth on soil temperature at 50 cm and 100 cm depths for over 2 years. The coldest summer soil temperatures were associated with thick organic layers. In summer, soil temperatures were colder under spruce stands than under shrub canopies and forest openings, whereas the thick snow cover in spruce stands and forest openings maintained warmer winter soil temperatures than under shrub canopies. Well‐defined zero‐curtain periods during fall and spring could be an early indicator of current changes in the soil thermal regime of palsas. At the northern edge of discontinuous permafrost, non‐wooded palsas have the most favourable conditions for permafrost stability, because heterogeneous vegetation cover on wooded palsas promotes snow trapping and lateral heat transfer. Vegetation types should be considered in estimating future rates of permafrost degradation. Copyright © 2014 John Wiley & Sons, Ltd.
Nasal NO as a biomarker: Don't say NO to the many challenges of translational medicine
Authors: Voynow Judith A. , Montpetit Alison J. 
Published: October 2014

SummaryThis editorial summarizes the challenges of exhaled breath biomarker research particularly for nasal NO. We also introduce a new focus for Pediatric Pulmonology, a section on Translational Medicine. Pediatr Pulmonol. 2015; 50:100–102. © 2014 Wiley Periodicals, Inc.
Analysis of Polar Precursors of 1,3,5,7‐Tetranitro‐1,3,5,7‐tetrazocine (HMX) Using Hydrophilic Interaction Chromatography
Authors: Zhu Chao , Meng Zihui , Xu Zhibin , Xue Min , Wang Fengyan , Liu Yue , Lin Zhihui , Qin Guangmin , Ge Zhongxue , Wang Bozhou 
Published: October 2014

AbstractOctahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) is currently one of the most widely used explosives. 1,3,5,7‐Tetraacetyl‐1,3,5,7‐tetraazacyclooctane (TAT) is an attractive precursor for the synthesis of HMX; the nitration of this key precursor results in both high yield and purity under mild condition. TAT can be prepared either by acetylation of 2,6‐diacetyl‐pentamethylenetetramine (DAPT) or by the condensation of ACN and 1,3,5‐trioxane. However, TAT and DAPT are polar compounds, and are difficult to analyze using reverse phase liquid chromatography. Herein, a chromatography method for the direct separation of these polar compounds was developed using hydrophilic interaction chromatography (HILIC) using a Venusil HILIC column, with ACN/water (95/5, v/v) as the mobile phase. The chromatographic analysis and identification of these polar compounds provide valuable information for the optimization of the synthetic process of TAT.
6,6‐Dicyanopentafulvenes: Teaching an Old Dog New Tricks
Authors: Finke Aaron D. , Diederich François 
Published: October 2014

Abstract6,6‐Dicyanopentafulvene (DCF) is a fascinating molecular entity that consists of a cyclopentadiene ring conjugated to an exocyclic double bond bearing two cyano groups on its periphery. Herein, we give a brief history of the chemistry of DCFs prior to our arrival to the field in 2011, followed by a summary of our work. We show how substitution on the ring and the exocyclic bond affects the HOMO and LUMO energies of pentafulvenes and how the design of DCFs was exploited computationally for the first time. Shortly after the report of the first rational synthesis of DCFs, we discovered that DCFs had a vast and astonishing array of reactivities to form new molecular entities. Simple, catalyst‐free reactions between DCF acceptors and electron‐rich donors led to the formation of scaffolds of exceptional complexity. Furthermore, our discovery that DCFs are capable of undergoing mild pentafulvene‐to‐benzene rearrangements challenges previous conventions of fulvene chemistry.graphic
Lapland longspur mortality at an oil well drilling rig site, Laramie County, Wyoming
Authors: Ramirez Pedro , Dickerson Kimberly , Lindstrom Jim , Meteyer Carol U. , Darrah Scott 
Published: October 2014

ABSTRACTTwo hundred fifty‐one Lapland longspur (Calcarius lapponicus) carcasses were recovered around an oil well drilling rig in Laramie County, Wyoming, USA, on December 13–14, 2010, apparent victims of a winter storm and “light entrapment” from the lights on the drilling rig during foggy conditions. We found Lapland longspur carcasses distributed around the drilling rig from 33 m to 171 m. Investigators did not find evidence of bird carcasses on the drilling rig deck or equipment immediately adjacent to the drilling rig. We ruled out chemical toxins and disease as a cause of mortality. Weather conditions, the circular depositional pattern of carcasses around the drilling rig, and bird necropsy results led investigators to conclude that the Lapland longspur mortality was the result of the migrating birds entering the area illuminated by the drilling rig lights in freezing fog and the birds repeatedly circling the drilling rig until they fell to the ground in exhaustion and dying from subsequent trauma. Further research is needed to understand how to most effectively adjust lighting of onshore drilling rigs to reduce the potential for avian light entrapment. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
PHF21B as a candidate tumor suppressor gene in head and neck squamous cell carcinomas
Authors: Bertonha Fernanda Bernardi , Barros Filho Mateus de Camargo , Kuasne Hellen , dos Reis Patricia Pintor , da Costa Prando Erika , Muñoz Juan José Augusto Moyano , Roffé Martín , Hajj Glaucia Noeli Maroso , Kowalski Luiz Paulo , Rainho Claudia Aparecida , Rogatto Silvia Regina 
Published: October 2014

A significant association between DNA losses on 22q13.31 and head and neck squamous cell carcinomas (HNSCC) was previously reported by our group. Our data indicated that PHF21B gene, mapped on 22q13.31 and encoding a protein with function of chromatin‐mediated transcriptional regulation, might be a putative tumor suppressor gene. To test this hypothesis, gene copy number was assessed in 75 HNSCC and 49 matched peripheral blood samples. PHF21B losses were detected in 43 tumors and were significantly associated with patients with familial history of cancer (P < 0.0001); i.e., 36/43 cases showed a positive family history of cancer and 22/36 had first‐degree relatives with cancer (P = 0.049). In attempt to investigate other mechanisms for PHF21B loss of function, DNA sequencing was performed and no mutations were detected. We next evaluated the gene expression levels after inhibition of DNA methylation in nine HNSCC and breast carcinoma cell lines. Additionally, PHF21B expression levels were evaluated in colon cancer HCT116 cells as well as in its counterpart DKO (double knockout of DNMT1 and DNMT3B). The higher expression levels of PHF21B gene detected in DKO cells were inversely correlated with the DNA methylation. Further, DNA methylation in the specific promoter‐associated CpG Island was investigated. Interestingly, gene hypermethylation was detected in 13/37 tumors: 5/13 HNSCC cases had family history of cancer in first‐degree relatives and 8/13 showed both, DNA methylation and PHF21B losses in the tumor sample. One patient had PHF21B loss in the peripheral blood cells and PHF21B methylation in the tumor sample. Additionally, overexpression of PHF21B in cell lines drastically reduces clonogenic and migratory abilities. These data suggest that PHF21B is a novel tumor suppressor gene that can be inactivated by genetic and epigenetic mechanisms in the human cancer.