bluuebunny/crossref_metadata_2025 huggingface dataset:
A Markovian analytical framework for public‐safety video sharing by device‐to‐device communications
Authors: Zhao Quanxin , Han Shuai , Mao Yuming , Leng Supeng , Min Geyong , Hu Jia , Najjari Noushin
Published: February 2017

Monitoring video of city surveillance camera plays an important role in public security and disaster relief, which is often used by first responder teams, such as firefighters and police officers. The first responders in emergency situations require consistent connection with one another and request the remote real‐time monitoring video for effective cooperation and coordination. However, the capacity and privacy of public wireless networks fail to satisfy the requirements in many emergency scenarios, which often leads to exceptionally high traffic loads and insecurity. Device‐to‐device (D2D) communications have been deemed a key solution for this problem, as responders can use D2D links for traffic offloading and secure communications. To investigate the D2D‐based solution for public safety video sharing, this paper focuses on the Focus Geographical Area (FGA) video consisting of multiple camera streams requiring higher bandwidth consumption than that of the traditional single‐camera stream, which attracts a large number of contents delivery requests in emergency situations. This paper develops a new Traffic Burden Switching Markovian (TBSM) model to evaluate the performance of transmitting real‐time FGA video in wireless networks with D2D communications. First, a novel D2D area model is introduced to characterize link‐switching in wireless D2D communication networks. Based on the proposed D2D area model, the state and transition matrix of TBSM model are then derived by jointly considering user mobility, link‐switching, and FGA video view‐switching. Thereafter, some key performance metrics including system offloading ratio, D2D link‐switching ratio, and view‐switching ratio are derived on the basis of coverage probability and ergodic rate. The performance results show the significant varying performance among D2D areas with different geographical locations in D2D enabled wireless networks, which is referred to as multi‐D2D‐area diversity. The excellent match between simulation and model results validates the accuracy of the TBSM model, which can be used to provide guidelines for the deployment and optimization of future wireless video networks with D2D communications.
CBMR: An optimized MapReduce for item‐based collaborative filtering recommendation algorithm with empirical analysis
Authors: Li Chenyang , He Kejing
Published: February 2017

Item‐based collaborative filtering (CF) is a model‐based algorithm for making recommendations. In the algorithm, the similarity between items are calculated by using a number of similarity measures, and then these similarity values are used to predict ratings for users. However, if the number of items and users grows to millions, the scalability and the processing efficiency of item‐based CF can be hindered by some hardware constraints. To solve this problem, we propose an optimized MapReduce for item‐based CF algorithm integrated with empirical analysis. Through extensive experiments on real‐world datasets, we demonstrate the advantages of our approach by evaluating its execution time and by comparing its shuffle phase overhead with the conventional methods. The experimental results suggest that our approach has better performance when processing large‐scale datasets.
Feasibility of a Supporting‐Salt‐Free Nonaqueous Redox Flow Battery Utilizing Ionic Active Materials
Authors: Milshtein Jarrod D. , Fisher Sydney L. , Breault Tanya M. , Thompson Levi T. , Brushett Fikile R.
Published: February 2017

Nonaqueous redox flow batteries (NAqRFBs) are promising devices for grid‐scale energy storage, but high projected prices could limit commercial prospects. One route to reduced prices is to minimize or eliminate the expensive supporting salts typically employed in NAqRFBs. Herein, the feasibility of a flow cell operating in the absence of supporting salt by utilizing ionic active species is demonstrated. These ionic species have high conductivities in acetonitrile (12–19 mS cm−1) and cycle at 20 mA cm−2 with energy efficiencies (>75 %) comparable to those of state‐of‐the‐art NAqRFBs employing high concentrations of supporting salt. A chemistry‐agnostic techno‐economic analysis highlights the possible cost savings of minimizing salt content in a NAqRFB. This work offers the first demonstration of a NAqRFB operating without supporting salt. The associated design principles can guide the development of future active species and could make NAqRFBs competitive with their aqueous counterparts.
Morpheme‐based Reading and Spelling in Italian Children with Developmental Dyslexia and Dysorthography
Authors: Angelelli Paola , Marinelli Chiara Valeria , De Salvatore Marinella , Burani Cristina
Published: February 2017

Italian sixth graders, with and without dyslexia, read pseudowords and low‐frequency words that include high‐frequency morphemes better than stimuli not including any morpheme. The present study assessed whether morphemes affect (1) younger children, with and without dyslexia; (2) spelling as well as reading; and (3) words with low‐frequency morphemes. Two groups of third graders (16 children with dyslexia and dysorthography and 16 age‐matched typically developing children) read aloud and spelt to dictation pseudowords and words. Pseudowords included (1) root + suffix in not existing combinations (e.g. lampadista, formed by lampad‐, ‘lamp’, and ‐ista, ‘‐ist’) and (2) orthographic sequences not corresponding to any Italian root or suffix (e.g. livonosto). Words had low frequency and included: (1) root + suffix, both of high frequency (e.g. bestiale, ‘beastly’); (2) root + suffix, both of low frequency (e.g. asprigno, ‘rather sour’); and (3) simple words (e.g. insulso, ‘vapid’). Children with dyslexia and dysorthography were less accurate than typically developing children. Root + suffix pseudowords were read and spelt more accurately than non‐morphological pseudowords by both groups. Morphologically complex (root + suffix) words were read and spelt better than simple words. However, task interacted with morphology: reading was not facilitated by low‐frequency morphemes. We conclude that children acquiring a transparent orthography exploit morpheme‐based reading and spelling to face difficulties in processing long unfamiliar stimuli. Copyright © 2017 John Wiley & Sons, Ltd.
Enhancing the Magnetic Heating Capacity of Iron Oxide Nanoparticles through Their Postproduction Incorporation into Iron Oxide–Gold Nanocomposites
Authors: Bell Gavin , Bogart Lara K. , Southern Paul , Olivo Malini , Pankhurst Quentin A. , Parkin Ivan P.
Published: February 2017

Small variations in the synthesis conditions of iron oxide–gold nanocomposites, made in an aqueous medium by a coprecipitation reaction, have a significant effect on the magnetic‐heating properties of the iron oxide nanoparticles. Citric acid coated magnetite/maghemite (Fe3O4/γ‐Fe2O3) nanoparticles were used as a Turkevich‐style reducing agent and added to varying concentrations of HAuCl4 to form iron oxide–gold nanoparticle composites with Fe/Au molar ratios ranging from ca. 5:1 to ca. 300:1. The magnetic‐heating capacities of the products were measured in a high‐frequency alternating field (peak amplitude 6.6 kA/m, frequency 967 kHz), to determine both the specific absorption rates (SARs) and the intrinsic loss powers (ILPs) of the products. The iron oxide (FeOx) precursor presented a moderately high SAR of 33.9 W/gFeOx and an ILP of 0.8 nH m2/kgFeOx, but the iron oxide–gold nanocomposite formed with 0.75 mm HAuCl4 had an almost threefold‐enhanced heating capacity with a SAR of 88.3 W/gFeOx and an ILP of 2.1 nH m2/kgFeOx. This corresponds to an ILP of 3.0 nH m2/kgFe, which is as high as that of any commercially available material to date. This result has implications for the possible postproduction enhancement of the magnetic‐heating capacities of similar iron oxide systems as well as increasing the theranostic potential of such materials through the incorporation of Au nanoparticles, which may act as integrated binding sites for drugs or other beneficial biomolecules.
A Direct Synthesis of Isocytosine Analogues by Carbonylative Coupling of α‐Chloro Ketones and Guanidines
Authors: Capua Martina , Perrone Serena , Bona Fabio , Salomone Antonio , Troisi Luigino
Published: February 2017

A valuable and direct method for the synthesis of 2‐aminopyrimidin‐4‐one derivatives is described. The strategy relies on the Pd‐catalysed carbonylation of α‐chloro ketones in the presence of mono‐ and disubstituted guanidines. Although the strategy also gave 2‐aminoimidazole derivatives as minor products, good chemoselectivity in favour of the six‐membered ring was achieved in all experiments. The in‐situ formation of a (β‐oxoacyl)palladium species has been invoked as the key step for the multicomponent process. Moreover, the method described could be of interest from a biological point of view, because it constitutes a straightforward strategy for the synthesis of structural analogues of the unnatural nucleobase isocytosine.
Establishing Consensus Stereostructures for the Naphthoquinonopyrano‐γ‐lactone Natural Products (–)‐Arizonin B1 and (–)‐Arizonin C1 by Total Syntheses. Diastereocontrol of Oxa‐Pictet–Spengler Cyclizations by Protective‐Group Optimization
Authors: Neumeyer Markus , Brückner Reinhard
Published: February 2017

Previous total syntheses of arizonin C1 (4) led to opposite assignments of its absolute configuration. Here, we report the fourth total synthesis thereof. In addition, we disclose the first total synthesis of arizonin B1 (3) proceeding differently than via arizonin C1. The stereocenters of the two targets stemmed from an asymmetric dihydroxylation and an ensuing oxa‐Pictet–Spengler cyclization. Their configurations were in line with Fernandes' assignments. Protective‐group variation in the substrate modulated the diastereoselectivity of the Pictet–Spengler cyclization between 77:23 in favor of a trans disubstitution at C‐3a vs. C‐5 – used for preparing the natural (–)‐arizonins C1 and B1 – and 100:0 in favor of a cis disubstitution – exploited for synthesizing the unnatural (+)‐5‐epi‐arizonins C1 and B1. All naphthalenes of the present study were derived from the (benzyloxy)methoxynaphthalenediol 19. It resulted from a Diels–Alder reaction of the aryne 17a with the siloxyfuran 18a.
Geochronology and phase equilibria modelling of ultra‐high temperature sapphirine + quartz‐bearing granulite at Usilampatti, Madurai Block, Southern India
Authors: Prakash D. , Yadav R. , Tewari S. , Frimmel H. E. , Koglin N. , Sachan H. K. , Yadav M. K.
Published: February 2017

Sapphirine‐bearing granulite from Usilampatti in the Madurai block of southern India preserves a variety of mineral textures and reactions that help in reconstructing a three‐stage metamorphic evolution. Corroded biotite, sillimanite and quartz inclusions within garnet represent relics from the prograde history. Peak metamorphic conditions were attained with the development of sapphirine + quartz in textural equilibrium (Stage 1). This was followed by nearly isothermal decompression, leading to the formation of sapphirine + cordierite at Stage 2. Subsequent retrograde hydration (Stage 3) is only locally evident. Using the Perple_X software and the model system NCKFMASH, the peak P‐T conditions were estimated from core compositions, and the retrograde evolution was deduced from rim or symplectite compositions of different minerals as computed by isopleths of XMg garnet, XCa garnet, XMg orthopyroxene, XMg sapphirine and XMg biotite. The P‐T conditions for Stage 1 thus obtained, and supported by thermodynamic modelling using the winTWQ programme, is approximately 9 kbar and 940°C. Stage 2 conditions were constrained as 6.7 kbar and 900°C. Dating of zircon and monazite in the sapphirine‐bearing granulite and associated gneisses by the U‐Pb method using LA‐ICP‐MS indicates metamorphic overprint of zircon (lower intercept ages of discordant data arrays) at 546 ± 8 and 547 ± 11 Ma and metamorphic growth of monazite between 542 ± 3 and 551 ± 2 Ma. Upper intercept ages for zircon point to zircon growth at approximately 2514 ± 66 Ma. Although it remains unclear whether the metamorphic age data refer to Stage 1 or Stage 2 or, most likely, a continuum between both, they clearly document a late Ediacaran age for ultra‐high temperature (UHT) metamorphism in the area, which, based on the obtained P‐T path, was most likely the result of crustal thickening followed by uplift and erosion. Thus, it is concluded that the sapphirine‐bearing granulites formed in response to Pan‐African orogeny that led to the collision of the western and eastern Madurai domains, whereas initial zircon growth probably took place during late Neoarchaean arc magmatism that formed much of the western domain. Copyright © 2017 John Wiley & Sons, Ltd.
Late Paleozoic tectonic evolution of the central Great Xing'an Range, northeast China: geochronological and geochemical evidence from igneous rocks
Authors: Zhang Ying , Pei Fu‐Ping , Wang Zhi‐Wei , Xu Wen‐Liang , Li Yu , Wang Feng , Zhou Zhong‐Biao
Published: February 2017

We present zircon U–Pb and Hf isotopic and whole‐rock geochemical data for late Paleozoic igneous rocks in the central Great Xing'an Range, northeast China, to constrain the late Paleozoic amalgamation history of the united Xing'an–Erguna and Songnen–Zhangguangcai Range massifs. Based on zircon U–Pb dating, we ascertain three main stages of magmatic events: Late Devonian (381–364 Ma), early Carboniferous (360–341 Ma), and late early Carboniferous–early Permian (328–271 Ma). Late Devonian rhyolites originated from partial melting of Meso‐proterozoic accreted lower crust. The crust‐derived rhyolites and coeval mantle‐derived basalts constitute a bimodal volcanic association in the west. Early Carboniferous igneous rocks include syenogranites, monzogranites, gabbro diorites, and gabbros. The granitoids are derived from partial melting of Meso‐proterozoic accreted lower crust. The gabbros and gabbro diorites show the spatial variation in zircon εHf(t) values (−0.53 to +0.84 in the east and +12.3 to +13.5 in the west), which imply that they were mainly derived from metasomatized mantle wedge and asthenosphere mantle, respectively. These characteristics indicate that northwest‐towards high‐angle subduction of the Paleo‐Asian Ocean plate beneath the united Xing'an–Erguna Massif induced arc magmatism in the east and back‐arc magmatism (similar to back‐arc rift) in the west during the Late Devonian to early Carboniferous. Late early Carboniferous–early Permian sub‐alkaline and alkaline igneous rocks are characterized by multiple sources, such as the depleted mantle, juvenile lower crust, and thickening lower crust. Their temporal variations in geochemical characteristics imply that the central Great Xing'an Range was situated under a transitional setting from syn‐collisional to post‐collisional during the late early Carboniferous to early Permian. Using the combined insight from lithofacies palaeogeography and regional magmatisms, we suggest amalgamation of the united Xing'an–Erguna and Songnen–Zhangguangcai Range massifs occurred during the late early Carboniferous to late Carboniferous. Copyright © 2017 John Wiley & Sons, Ltd.
Paleokarst of the Lianglitage Formation related to tectonic unconformity at the top of the Ordovician in the eastern Tazhong Uplift, Tarim Basin, NW China
Authors: Gao Da , Lin Changsong , Hu Mingyi , Yang Haijun , Huang Lili
Published: February 2017

The Lianglitage Formation (also named Lianglitag Formation) is an important hydrocarbon reservoir in the Tarim Basin; the reef and shoal facies of this formation have previously been extensively investigated. The paleokarst of the formation related to a tectonic unconformity at the top of the Ordovician (Tg5) has, however, not been widely investigated. In this paper, we undertake a comprehensive study of the paleokarst by an integrated analysis of seismic data, well‐logging data, and core data. Several geomorphologic units that formed at the end of the Ordovician period are identified, including a fault‐thrust uplift high, inter‐uplifts sag, uplift platform, and fault‐thrust anticline; these units are controlled by west–east and northwest–southeast striking faults. The thickness of erosion is estimated to be 200 to 700 meters. The paleokarst is characterized by large and small caves, dense vugs, and dissolution fractures. Large caves predominantly developed in exposed areas and on the slopes. Dense vugs and small caves, features that contribute to premium hydrocarbon reservoirs, are generally tens of meters away from the unconformity, whereas dissolution fractures, predominantly filled by mud and silts, are situated in close proximity to the unconformity and faults. Four karst zones can be identified from vertical profiles: weathered crust (1–2 m thick), vertical infiltration zone (tens of meters thick), phreatic zone (tens to hundreds of meters thick), and a bottom zone that is largely unaffected by karstification. The karst of the Lianglitage Formation at the end of the Ordovician was mainly controlled by tectonic movement, paleogeomorphology, lithofacies, faults, and fractures. The karstification process is summarized in a karst model.
Sensory tractography and robot‐quantified proprioception in hemiparetic children with perinatal stroke
Authors: Kuczynski Andrea M. , Carlson Helen L. , Lebel Catherine , Hodge Jacquie A. , Dukelow Sean P. , Semrau Jennifer A. , Kirton Adam
Published: February 2017

Perinatal stroke causes most hemiparetic cerebral palsy, resulting in lifelong disability. We have demonstrated the ability of robots to quantify sensory dysfunction in hemiparetic children but the relationship between such deficits and sensory tract structural connectivity has not been explored. It was aimed to characterize the relationship between the dorsal column medial lemniscus (DCML) pathway connectivity and proprioceptive dysfunction in children with perinatal stroke. Twenty‐nine participants (6–19 years old) with MRI‐classified, unilateral perinatal ischemic stroke (14 arterial, 15 venous), and upper extremity deficits were recruited from a population‐based cohort and compared with 21 healthy controls. Diffusion tensor imaging (DTI) defined DCML tracts and five diffusion properties were quantified: fractional anisotropy (FA), mean, radial, and axial diffusivities (MD, RD, AD), and fiber count. A robotic exoskeleton (KINARM) tested upper limb proprioception in an augmented reality environment. Correlations between robotic measures and sensory tract diffusion parameters were evaluated. Lesioned hemisphere sensory tracts demonstrated lower FA and higher MD, RD, and AD compared with the non‐dominant hemisphere of controls. Dominant (contralesional) hemisphere tracts were not different from controls. Both arterial and venous stroke groups demonstrated impairments in proprioception that correlated with lesioned hemisphere DCML tract diffusion properties. Sensory tract connectivity is altered in the lesioned hemisphere of hemiparetic children with perinatal stroke. A correlation between lesioned DCML tract diffusion properties and robotic proprioceptive measures suggests clinical relevance and a possible target for therapeutic intervention. Hum Brain Mapp 38:2424–2440, 2017. © 2017 Wiley Periodicals, Inc.
Anomalous single‐subject based morphological cortical networks in drug‐naive, first‐episode major depressive disorder
Authors: Chen Taolin , Kendrick Keith M. , Wang Jinhui , Wu Min , Li Kaiming , Huang Xiaoqi , Luo Yuejia , Lui Su , Sweeney John A. , Gong Qiyong
Published: February 2017

Major depressive disorder (MDD) has been associated with disruptions in the topological organization of brain morphological networks in group‐level data. Such disruptions have not yet been identified in single‐patients, which is needed to show relations with symptom severity and to evaluate their potential as biomarkers for illness. To address this issue, we conducted a cross‐sectional structural brain network study of 33 treatment‐naive, first‐episode MDD patients and 33 age‐, gender‐, and education‐matched healthy controls (HCs). Weighted graph‐theory based network models were used to characterize the topological organization of brain networks between the two groups. Compared with HCs, MDD patients exhibited lower normalized global efficiency and higher modularity in their whole‐brain morphological networks, suggesting impaired integration and increased segregation of morphological brain networks in the patients. Locally, MDD patients exhibited lower efficiency in anatomic organization for transferring information predominantly in default‐mode regions including the hippocampus, parahippocampal gyrus, precuneus and superior parietal lobule, and higher efficiency in the insula, calcarine and posterior cingulate cortex, and in the cerebellum. Morphological connectivity comparisons revealed two subnetworks that exhibited higher connectivity strength in MDD mainly involving neocortex‐striatum‐thalamus‐cerebellum and thalamo‐hippocampal circuitry. MDD‐related alterations correlated with symptom severity and differentiated individuals with MDD from HCs with a sensitivity of 87.9% and specificity of 81.8%. Our findings indicate that single subject grey matter morphological networks are often disrupted in clinically relevant ways in treatment‐naive, first episode MDD patients. Circuit‐specific changes in brain anatomic network organization suggest alterations in the efficiency of information transfer within particular brain networks in MDD. Hum Brain Mapp 38:2482–2494, 2017. © 2017 Wiley Periodicals, Inc.
Effect of a hallucinogenic serotonin 5‐HT2A receptor agonist on visually guided, hippocampal‐dependent spatial cognition in C57BL/6J mice
Authors: Zhang Gongliang , Cinalli David , Stackman Robert W.
Published: February 2017

By acting on serotonin 5‐HT2A receptors (5‐HT2ARs), serotonergic psychedelic drugs induce perceptual and visual hallucinations by increasing neuronal excitability and altering visual‐evoked neuronal responses. The present study was designed to examine whether the perceptual alterations induced by a serotonergic psychedelic drug would affect the integrity of hippocampal‐dependent, visually guided spatial cognition. phenylalkylamine hallucinogen TCB‐2 is a selective agonist of 5‐HT2ARs. Mice received TCB‐2 (1.0 mg kg−1, i.p.), and spatial behaviors and hippocampal electrophysiological responses were measured with water maze tasks and in vivo single‐unit recording, respectively. TCB‐2 did not affect visual cue approach behavior in the visible platform water maze, but increased the latency of trained mice to initiate goal‐directed swimming during a probe test in the hidden platform Morris water maze, which could be prevented by 5‐HT2AR antagonist MDL 11,939. Interestingly, TCB‐2 did not affect the efficiency of the swim path or the proper use of distal visual cues during the probe test. Hippocampal place cell activity is considered to represent spatial and context‐specific episodic memory. Systemic TCB‐2 did not affect previously established place fields of CA1 neurons in mice exploring a familiar environment, or the remapping of place cells when the mice explored a novel environment. However, TCB‐2 impaired the long‐term stability of place fields for the novel environment initially encoded under the influence of TCB‐2, which could be prevented by 5‐HT2AR antagonist MDL 11,939. Our data indicate that hallucinogenic 5‐HT2AR agonist delays the initiation of spatial search behavior, but does not impair the use of visual cues to guide goal‐directed spatial behavior. Moreover, activation of 5‐HT2ARs does not impair the coding and retrieval of spatial information, but impairs the long‐term stability of new formed place fields of CA1 neurons. © 2017 Wiley Periodicals, Inc.
Association between genetic variation within vitamin D receptor‐DNA binding sites and risk of basal cell carcinoma
Authors: Lin Yuan , Chahal Harvind S. , Wu Wenting , Cho Hyunje G. , Ransohoff Katherine J. , Dai Hongji , Tang Jean Y. , Sarin Kavita Y. , Han Jiali
Published: February 2017

An increasing number of studies have reported a protective association between vitamin D and cancer risk. The vitamin D endocrine system regulates transcriptional programs involved in inflammation, cell growth and differentiation through the binding of vitamin D receptor (VDR) to specific VDR elements. However, limited attention has been given to the role of variation within VDR binding sites in the development of basal cell carcinoma (BCC). Across 2,776 previously identified VDR binding sites, we identified 2,540 independent single‐nucleotide polymorphisms (SNPs) and examined their associations with BCC risk in a genome‐wide association meta‐analysis totaling 17,187 BCC cases and 287,054 controls from two data sets. After multiple testing corrections, we identified two SNPs at new loci (rs16917546 at 10q21.1: odds ratio (OR) = 1.06, p = 3.16 × 10−7 and rs79824801 at 12q13.3: OR = 1.10, p = 1.88 × 10−5) for the first time as independently related to BCC risk in meta‐analysis; and both SNPs were nominally significant in two data sets. In addition, the SNP rs3769823 within VDR binding site at a previously reported BCC susceptibility locus (2q33.1, rs13014235) also exhibited a significant association (OR = 1.12, p = 3.99 × 10−18). A mutually adjusted model suggested that rs3769823 explained the signal in this region. Our findings support the hypothesis that inherited common variation in VDR binding sites affects the development of BCC.
Uptake of cervical cancer screening among the migrant population of Prato Province, Italy
Authors: Comparetto Ciro , Epifani Cristina , Manca Maria C. , Lachheb Abdelghani , Bravi Stefano , Cipriani Francesco , Bellomo Francesco , Olivieri Simone , Fiaschi Chiara , Di Marco Laura , Nardi Valentina , Spinelli Giansenio , Borruto Franco
Published: February 2017

Objective

To determine the level of participation in cervical cancer screening among the migrant population of Prato Province, Italy.

Methods

A retrospective cross‐sectional study was conducted using data for women aged 25–64 years who were resident in one of the municipalities of Prato Province and had received at least one invitation to undergo a cervical cancer screening test. Data were extracted from both the Local Health Unit Serviceable Registry and cervical cancer screening archives for the period July 1, 2004, to June 30, 2007.

Results

Of the 69 459 residents eligible for cervical cancer screening, 7339 (10.6%) did not have Italian citizenship. Adherence with cervical cancer screening among the migrant population was lower than that of the Italian resident population: uptake increased from 52.4% in 2004 to 57.3% in 2007 among the Italian resident population, but decreased from 31.4% to 28.2% among migrants.

Conclusion

The migrant population of Prato Province has decreased adherence with cervical cancer screening.
Precoating of biphasic calcium phosphate bone substitute with atelocollagen enhances bone regeneration through stimulation of osteoclast activation and angiogenesis
Authors: Kim Beom‐Su , Yang Sun‐Sik , Lee Jun
Published: February 2017

Type I collagen (Col) is a naturally polymerizing protein and important extracellular matrix bone component. The aim of this study was to improve bone regeneration capacity by precoating the surface of biphasic calcium phosphate (BCP) granules with AT‐Col, and evaluating its biological effects. BCP granules were precoated with AT‐Col using adsorption and lyophilization method. Morphology of AT‐Col precoated surfaces was observed using scanning electron microscopy (SEM). Biocompatibility and osteogenic activity of AT‐Col were determined in vitro with human mesenchymal stem cell (hMSCs). In vivo bone healing efficiency and related biological effects were determined using a rabbit calvarial defect model. SEM results revealed numerous irregularly distributed AT‐Col polymer clusters on BCP granule surface. Biocompatibility experiments demonstrated that AT‐Col was non‐cytotoxic, and that cell proliferation, adhesion, and osteogenic activity were improved by AT‐Col precoating. After in vivo surgical implantation into bone defects, new bone formation was improved by AT‐Col granule precoating. Specifically, 8 weeks post‐surgery, percentage bone volume was significantly higher in AT‐Col/BCP animals (35.02 ± 1.89%) compared with BCP‐treated animals (8.94 ± 1.47%) (p < 0.05). Furthermore, tartrate‐resistant acid phosphatase staining and CD31 immunohistochemical staining revealed that osteoclast activation and new blood vessel formation in vivo were also induced by AT‐Col precoating. Collectively, these data indicate that AT‐Col/BCP may be potentially used as a bone substitute to enable effective bone regeneration through enhanced new blood vessel formation and osteoclast activation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1446–1456, 2017.
Effects of an endodontic auxiliary chemical substance on the bond strength of two methacrylate‐based endodontic sealers to dentin
Authors: Fuzinatto Roger Nicolini , Farina Ana Paula , Souza Matheus Albino , Miyagaki Daniela Cristina , Randi Ferraz Caio Cézar , Cecchin Doglas
Published: February 2017

Purpose

To evaluate the influence of irrigation protocols and drying procedures on the bond strength of two methacrylate‐based sealers to dentin and the associated failure pattern using scanning electron microscopy (SEM).

Materials and Methods

Fifty single‐rooted human teeth were prepared with an irrigation protocol using either 5.25% sodium hypochlorite (NaOCl) or 2% chlorhexidine (CHX) and 17% EDTA (ethylenediaminetetraacetic acid) for smear layer removal. The following subgroups were also created based on drying of the root canal walls: paper points, the canals were blot dried with paper points with the last one appearing dry; or, ethanol, excess distilled water was removed with paper points followed by dehydration with 95% ethanol for 1 min and blotting with paper points. Each group was divided into two subgroups on the basis of the root canal sealer: EndoREZ and RealSeal SE. Bond strength was measured by the push‐out test. The data were analyzed by ANOVA/Tukey HSD (α = 0.05). Failure patterns were classified as adhesive, cohesive, and mixed in the SEM analysis. The failure mode was evaluated by the chi‐squared test (α = 0.05).

Results

The roots irrigated with NaOCl showed significantly lower bond strength than the roots irrigated with CHX (p < .05). RealSeal SE showed higher bond strength when compared with EndoREZ (p < .05). The highest values of bond strength were in the CHX and ethanol groups with RealSeal SE (p < .05). An increase in adhesive failure was observed in the NaOCl and EDTA group.

Conclusions

The bond strength of both methacrylate‐based sealers is influenced by the irrigant protocol.
Pharmacological inhibition of myostatin protects against skeletal muscle atrophy and weakness after anterior cruciate ligament tear
Authors: Wurtzel Caroline NW , Gumucio Jonathan P , Grekin Jeremy A , Khouri Roger K , Russell Alan J , Bedi Asheesh , Mendias Christopher L
Published: February 2017

Anterior cruciate ligament (ACL) tears are among the most frequent knee injuries in sports medicine, with tear rates in the US up to 250,000 per year. Many patients who suffer from ACL tears have persistent atrophy and weakness even after considerable rehabilitation. Myostatin is a cytokine that directly induces muscle atrophy, and previous studies rodent models and patients have demonstrated an upregulation of myostatin after ACL tear. Using a preclinical rat model, our objective was to determine if the use of a bioneutralizing antibody against myostatin could prevent muscle atrophy and weakness after ACL tear. Rats underwent a surgically induced ACL tear and were treated with either a bioneutralizing antibody against myostatin (10B3, GlaxoSmithKline) or a sham antibody (E1‐82.15, GlaxoSmithKline). Muscles were harvested at either 7 or 21 days after induction of a tear to measure changes in contractile function, fiber size, and genes involved in muscle atrophy and hypertrophy. These time points were selected to evaluate early and later changes in muscle structure and function. Compared to the sham antibody group, 7 days after ACL tear, myostatin inhibition reduced the expression of proteolytic genes and induced the expression of hypertrophy genes. These early changes in gene expression lead to a 22% increase in muscle fiber cross‐sectional area and a 10% improvement in maximum isometric force production that were observed 21 days after ACL tear. Overall, myostatin inhibition lead to several favorable, although modest, changes in molecular biomarkers of muscle regeneration and reduced muscle atrophy and weakness following ACL tear. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2499–2505, 2017
Epidemiology and risk factors for infection after living donor liver transplantation
Authors: Abad Cybele Lara R. , Lahr Brian D. , Razonable Raymund R.
Published: February 2017

The epidemiology of infections after living donor liver transplantation (LDLT) is limited. We aimed to study the epidemiology and risk factors of infections after LDLT. The medical records of 223 adult patients who underwent LDLT from January 1, 2000 to August 31, 2015 were reviewed for all infections occurring up to 1 year. We estimated the cumulative incidence of infection using the Kaplan‐Meier product limit method. Risk factors were analyzed with time‐dependent Cox regression modeling. The majority of patients were Caucasian (94.6%) and male (64.6%), and the median age at transplantation was 55 years. The most common indication for transplantation was primary sclerosing cholangitis (37.7%). A total of 122 patients developed an infection during the follow‐up period (1‐year cumulative event rate of 56%), with the majority (66%) of these occurring within 30 days after transplantation. Enterococcus sp. was the most frequent pathogen identified. Multivariate analysis showed that increased Model for End‐Stage Liver Disease (MELD) score (per 10‐point change: hazard ratio [HR], 1.59), history of recurrent infections prior to transplant (HR, 2.01), Roux‐en‐Y anastomosis (HR, 2.37), increased log‐number of packed red blood cell transfusions (HR, 1.39), and biliary complications (HR, 4.26) were independently associated with a higher risk of infection. Infections occur commonly after LDLT, with most infections occurring early and being related to the hepatobiliary system. Higher MELD scores, the type of biliary anastomosis, presence of biliary complications, and prior pretransplant infections are independently associated with a higher risk for infections. Liver Transplantation 23 465–477 2017 AASLD.
Stimuli‐Responsive Core Multishell Dendritic Nanocarriers
Authors: Mohammadifar Ehsan , Adeli Mohsen , Kharat Ali Nemati , Namazi Hassan , Haag Rainer
Published: February 2017

Multidomain polymeric nanoparticles containing different blocks with different properties have gained great interest for a wide range of applications in the past two decades. In this work, core multishell (CMS) structures consisting of hyperbranched polyglycerol as core and polylactide and polycaprolactone as shell structures are presented. Number of arms and thickness of shells have been manipulated by precise control over the molar ratios of monomer to terminal functional groups in the reaction feed. The ability of CMS to load and release small guest molecules and also the loading capacities are studied using Rose Bengal as a model dye. Loading capacity of CMS depends on molecular weight, type, and thickness of shells. Due to the difference in polarity and solubility of different blocks, the CMS nanocarriers show medium‐responsive behavior whereupon the encapsulated guest molecules are released in a controlled manner.

image
Anionic Polymerization of Divinylbenzenes Possessing Methoxy Group
Authors: Otake Kohei , Matsumoto Masayoshi , Tanaka Shunsuke , Uchida Satoshi , Goseki Raita , Hirao Akira , Ishizone Takashi
Published: February 2017

The anionic polymerizations of novel methoxy‐substituted divinylbenzenes possessing nonequivalent vinyl groups, such as 2‐methoxy‐1,4‐divinylbenzene (1), 4‐methoxy‐1,2‐divinylbenzene (2), and 4‐methoxy‐1,3‐divinylbenzene (3), are carried out with oligo(α‐methylstyryl)lithium (αMSLi) in the presence of potassium tert‐butoxide (tBuOK) in tetrahydrofuran at −78 °C. The poly(1)–poly(3) obtained with αMSLi/tBuOK are completely soluble and possess predicted molecular weights and narrow molecular weight distributions (MWD) (M
w/M
n < 1.1). On the other hand, the corresponding symmetrical divinylbenzenes, 2‐methoxy‐1,3‐divinylbenzene (4) and 5‐methoxy‐1,3‐divinylbenzene (5), undergo anionic polymerization to afford polymers with broad MWDs, indicating the occurrence of a serious intermolecular side reaction. The stability of the propagating carbanion derived from 1–3 is demonstrated by the quantitative efficiency of the sequential copolymerization with tert‐butyl methacrylate. The chemical structure of the repeating unit of poly(1)–poly(3) is characterized by the 1H and 13C nuclear magnetic resonance measurements, suggesting that the polymerization of asymmetrical divinylbenzenes, 1–3, proceeds mainly on one of the nonequivalent vinyl groups. The electronic and steric effects of the electron‐donating methoxy group play important roles in realizing the living anionic polymerization of these divinylbenzenes. The resulting poly(1)–poly(3) show a thermal cross‐linking property over 300 °C, indicating the reactivity of the residual pendant vinyl group in each repeating unit.

image
On Cartan's theorem for linear operators
Authors: Chen Wei , Han Qi , Qu Jingjing
Published: February 2017

In this paper, we describe a second main theorem of holomorphic curves in , of hyper‐order strictly less than 1, that involves a general linear operator . As an application, we derive a truncated second main theorem of degenerate holomorphic curves of hyper‐order strictly less than 1 using Nochka weights.
Associating hub‐directed multigraphs to arrowhead matrices
Authors: Marrero J. Abderramán , Valdés Juan Núñez , Villar María Trinidad
Published: February 2017

In this paper, we use the arrowhead matrices as a tool to study graph theory. More precisely, we deal with an interesting class of directed multigraphs, the hub‐directed multigraphs. We associate the arrowhead matrices with the adjacency matrices of a class of directed multigraph, and we obtain new properties of the second objects by using properties of the first ones. The hub‐directed multigraphs with potential use in applications are also defined. As main result, we show that a hub‐directed multigraph G(H) with adjacency matrix H∗ is a dominant hub‐directed multigraph if and only if H∗=CE, where C is the adjacency matrix of another directed multigraph and E is the adjacency matrix of a particular elementary dominant hub‐directed pseudo‐graph. Another decomposition of its Gram (arrowhead) matrix
is also given. Copyright © 2017 John Wiley & Sons, Ltd.
Serial echocardiography for immune‐mediated heart disease in the fetus: results of a risk‐based prospective surveillance strategy
Authors: Kan Nobuhiko , Silverman Earl D. , Kingdom John , Dutil Nathalie , Laskin Carl , Jaeggi Edgar
Published: February 2017

Objective

Mothers carrying anti‐Ro antibodies are frequently referred for weekly echocardiograms to early detect and treat antibody‐mediated fetal heart disease. We tested a surveillance strategy based on anti‐Ro antibody titers.

Methods

From 2009 to 2014, 232 pregnancies were referred for maternal anti‐Ro antibodies. At the baseline echocardiogram, anti‐Ro titers were measured by enzyme‐linked immunosorbent essay and results categorized as negative (<8 U/mL; n = 43; excluded), low–moderate positive (8–49 U/mL; n = 62; group 1) or high positive (50 – >100 U/mL; n = 127; group 2). Serial echocardiograms to ≥24 weeks were only recommended for group 2 mothers.

Results

Group 1 patients underwent significantly less fetal echocardiograms when compared with group 2 mothers (median 2 vs. 4; p < 0.001). Isolated endocardial fibroelastosis (n = 1) and incomplete (n = 4) or complete (n = 4) heart block were diagnosed in 9 (8%) pregnancies with anti‐Ro titers >100 U/mL but none with lower titers (odds ratio 17.78; p = 0.004). Incomplete block and endocardial fibroelastosis regressed with transplacental corticosteroid and immune globulin therapy.

Conclusions

Limiting serial fetal echocardiograms to women with high anti‐Ro antibody levels is safe and more cost effective. While numbers of echocardiograms were significantly reduced in referrals with anti‐Ro titers <50 U/mL, reversible abnormalities with prenatal treatment were detected by serial echocardiography in group 2 patients. © 2017 John Wiley & Sons, Ltd.
Types, frequencies, and burden of nonspecific adverse events of drugs: analysis of randomized placebo‐controlled clinical trials
Authors: Mahr Alfred , Golmard Clara , Pham Emilie , Iordache Laura , Deville Laure , Faure Pierre
Published: February 2017

Purpose

Scarce studies analyzing adverse event (AE) data from randomized placebo‐controlled clinical trials (RPCCTs) of selected illnesses suggested that a substantial proportion of collected AEs are unrelated to the drug taken. This study analyzed the nonspecific AEs occurring with active‐drug exposure in RPCCTs for a large range of medical conditions.

Methods

Randomized placebo‐controlled clinical trials published in five prominent medical journals during 2006–2012 were searched. Only trials that evaluated orally or parenterally administered active drugs versus placebo in a head‐to‐head setting were selected. For AEs reported from ≥10 RPCCTs, Pearson's correlation coefficients (r) were calculated to determine the relationship between AE rates in placebo and active‐drug recipients. Random‐effects meta‐analyses were used to compute proportions of nonspecific AEs, which were truncated at a maximum of 100%, in active‐drug recipients.

Results

We included 231 trials addressing various medical domains or healthy participants. For the 88 analyzed AE variables, AE rates for placebo and active‐drug recipients were in general strongly correlated (r > 0.50) or very strongly correlated (r > 0.80). The pooled proportions of nonspecific AEs for the active‐drug recipients were 96.8% (95%CI: 95.5–98.1) for any AEs, 100% (97.9–100) for serious AEs, and 77.7% (72.7–83.2) for drug‐related AEs. Results were similar for individual medical domains and healthy participants. The pooled proportion of nonspecificity of 82 system organ class and individual AE types ranged from 38% to 100%.

Conclusion

The large proportion of nonspecific AEs reported in active‐drug recipients of RPCCTs, including serious and drug‐related AEs, highlights the limitations of clinical trial data to determine the tolerability of drugs. Copyright © 2017 John Wiley & Sons, Ltd.
Adjusting the Ga grading during fast atmospheric processing of Cu(In,Ga)Se2 solar cell absorber layers using elemental selenium vapor
Authors: Schmidt Sebastian Simon , Wolf Christian , Rodriguez‐Alvarez Humberto , Bäcker Jan‐Peter , Kaufmann Christian Alexander , Merdes Saoussen , Ziem Florian , Hartig Manuel , Cinque Sonja , Dorbandt Iris , Köble Christine , Abou‐Ras Daniel , Mainz Roland , Schlatmann Rutger
Published: February 2017

We study the sequential fabrication of Cu(In,Ga)Se2 (CIGSe) absorber layers by using an atmospheric pressure selenization with a process duration of only a few minutes and the utilization of elemental selenium vapor from independent Se sources. This technology could proof to be an industrially relevant technology for the fabrication of thin‐film solar cells. Controlling the amount of Se provided during the selenization of metal precursors is shown to be an effective measure to adjust the Ga in‐depth distribution. A reduced Se supply for CIGSe formation leads to a more homogeneous Ga distribution within the absorber. The underlying growth dynamics is investigated by interrupting the selenization at different times. At first, CIGSe formation occurs in accordance with previously suggested growth paths and Ga segregates at the Mo back contact. Between 520 and 580 °C, the growth dynamics differs distinctly, and In and Ga distribute far more uniformly within the absorber depth. We also studied the impact of the precursor architecture. The best performing precursor in terms of efficiency of the respective solar cells was a multilayer with 22 In/CuGa/In triple layers. Simple bilayers stacks lead to films of higher roughness and correlated shunting. By optimizing the precursor architecture and the Ga in‐depth distribution in the CIGSe layer, a conversion efficiency of up to 15.5% (active area) could be achieved. To our knowledge, this is the highest reported efficiency for sulfur free CIGSe‐based solar cells utilizing fast (few minutes) atmospheric processes and elemental Se vapor. Copyright © 2017 John Wiley & Sons, Ltd.
Synergistic activity profile of an antimicrobial peptide against multidrug‐resistant and extensively drug‐resistant strains of Gram‐negative bacterial pathogens
Authors: Pollini Simona , Brunetti Jlenia , Sennati Samanta , Rossolini Gian Maria , Bracci Luisa , Pini Alessandro , Falciani Chiara
Published: February 2017

Infection sustained by multidrug‐resistant and extensively drug‐resistant bacterial pathogens is often untreatable with the standard of care antibiotics, and the combination of anti‐infective compounds often represents the only therapeutic strategy to face this major clinical treat. SET‐M33 is a novel antimicrobial peptide (AMP) that has demonstrated in vitro and in vivo antimicrobial activity against Gram‐negative bacteria and has shown interesting features in preclinical evaluations. Particularly, it showed efficacy against a number of multidrug‐resistant and extensively drug‐resistant clinical strains of Gram‐negative pathogens, in in vitro and in vivo assessments.

Here, we explored the potential synergistic activity of SET‐M33 in combination with different standard of care antibiotics by the checkerboard method against a panel of six strains of Gram‐negative pathogens including multidrug‐resistant and extensively drug‐resistant Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii.

SET‐M33 showed synergistic activity with antibiotics of different families against these clinically relevant strains. A synergistic effect was observed for SET‐M33 in combination with rifampin, meropenem, aztreonam, and tobramycin mostly on K. pneumoniae and A. baumannii strains, while the SET‐M33 plus ciprofloxacin combination was additive with all tested strains. Synergy was not apparently linked to the bacterial species or phenotype but was rather strain‐specific, highlighting the need for individual strain testing for synergistic antimicrobial combinations.

These findings extend current knowledge on synergistic activity of AMPs in combination with conventional agents and support the potential role of SET‐M33 as a novel therapeutic agent against antibiotic‐resistant Gram‐negative pathogens. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.