bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wear behavior of light‐cured dental composite reinforced with silane‐treated nanosilica filler
Authors: Kumar Shiv Ranjan , Patnaik Amar , Bhat I.K. 
Published: January 2018

In this study, the effect of varying different weight fraction of silane‐treated nanosilica (0‐15 wt%) on the wear behavior of Bisphenol‐A glycidyl methacrylate/tri‐ethylene glycol dimethacrylate–based dental composite was analyzed. Fourier transform infrared spectroscopy, transmission electron microscope, and thermo‐gravimetric analysis were used to characterize silane‐treated filler. The in vitro wear tests were performed up to 20 000 cycles using dental wear simulator. Four different working conditions were discussed including 2‐body wear in distilled water and artificial saliva as well as 3‐body wear in slurry of poppy seed mixed in distilled water and poppy seed mixed in artificial saliva. The results suggested that composites with increased in nanosilica fillers exhibited lower wear volume and smoother worn surface in all working mediums. In 2‐body abrasive wear, the wear rate in distilled water was 10.05% more than that in artificial saliva condition. However, in 3‐body abrasive wear, the wear rate in slurry of poppy seed mixed in artificial saliva was 15.96% more than that in the medium of poppy seed mixed in distilled water condition. Also, the 2‐body abrasive wear rate was 56% and 22% more than the 3‐body abrasive wear rate in the slurry of distilled water and artificial saliva condition, respectively.
Resident cell lineages are preserved in pulmonary vascular remodeling
Authors: Crnkovic Slaven , Marsh Leigh M , El Agha Elie , Voswinckel Robert , Ghanim Bahil , Klepetko Walter , Stacher‐Priehse Elvira , Olschewski Horst , Bloch Wilhelm , Bellusci Saverio , Olschewski Andrea , Kwapiszewska Grazyna 
Published: January 2018

AbstractPulmonary vascular remodeling is the main pathological hallmark of pulmonary hypertension disease. We undertook a comprehensive and multilevel approach to investigate the origin of smooth muscle actin‐expressing cells in remodeled vessels. Transgenic mice that allow for specific, inducible, and permanent labeling of endothelial (Cdh5‐tdTomato), smooth muscle (Acta2‐, Myh11‐tdTomato), pericyte (Cspg4‐tdTomato), and fibroblast (Pdgfra‐tdTomato) lineages were used to delineate the cellular origins of pulmonary vascular remodeling. Mapping the fate of major lung resident cell types revealed smooth muscle cells (SMCs) as the predominant source of cells that populate remodeled pulmonary vessels in chronic hypoxia and allergen‐induced murine models. Combining in vivo cell type‐specific, time‐controlled labeling of proliferating cells with a pulmonary artery phenotypic explant assay, we identified proliferation of SMCs as an underlying remodeling pathomechanism. Multicolor immunofluorescence analysis showed a preserved pattern of cell type marker localization in murine and human pulmonary arteries, in both donors and idiopathic pulmonary arterial hypertension (IPAH) patients. Whilst neural glial antigen 2 (chondroitin sulfate proteoglycan 4) labeled mostly vascular supportive cells with partial overlap with SMC markers, PDGFRα‐expressing cells were observed in the perivascular compartment. The luminal vessel side was lined by a single cell layer expressing endothelial markers followed by an adjacent and distinct layer defined by SMC marker expression and pronounced thickening in remodeled vessels. Quantitative flow cytometric analysis of single cell digests of diverse pulmonary artery layers showed the preserved separation into two discrete cell populations expressing either endothelial cell (EC) or SMC markers in human remodeled vessels. Additionally, we found no evidence of overlap between EC and SMC ultrastructural characteristics using electron microscopy in either donor or IPAH arteries. Lineage‐specific marker expression profiles are retained during pulmonary vascular remodeling without any indication of cell type conversion. The expansion of resident SMCs is the major underlying and evolutionarily conserved paradigm of pulmonary vascular disease pathogenesis. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Voltage‐dependent photocurrent in irradiated GaAs solar cells
Authors: Salzberger Manuel , Rutzinger Martin , Nömayr Christel , Lugli Paolo , Zimmermann Claus G. 
Published: January 2018

AbstractGaAs single junction cells, representative of the middle cell in triple junction Ga 0.5In 0.5P/GaAs/Ge cells, were irradiated with various fluences of 1‐ and 3‐MeV electrons as well as 1‐MeV protons. The light I‐V curves measured at room temperature exhibit a voltage‐dependent photocurrent. The photocurrent is modeled taking into account the voltage‐dependent width of the space charge region in combination with a strongly decreased minority carrier diffusion length. By extracting the width of the space charge region from capacitance measurements and the base layer diffusion length from the external quantum efficiency of the cell, the experimental behavior is reproduced accurately.
Impact of bulk impurity contamination on the performance of high‐efficiency n‐type silicon solar cells
Authors: Richter Armin , Benick Jan , Fell Andreas , Hermle Martin , Glunz Stefan W. 
Published: January 2018

AbstractThe experimental variation of wafer thickness and resistivity at device level combined with a comprehensive device simulation study allows the identification of dominating recombination‐induced power loss mechanisms in high‐efficiency n‐type silicon solar cells (A. Richter et al, Sol. Energy Mater. Sol. Cells 173, p. 96, 2017). Under the assumption of specific Shockley‐Read‐Hall (SRH) recombination parameters, impurity recombination within the silicon bulk was identified as one main source for efficiency losses particularly for solar cells made of high‐resistivity silicon. In this work, we extend that analysis approach focusing on the SRH recombination parameters in order to investigate whether certain properties of these recombination‐active impurities can be identified using this kind of simulation‐based analysis. Reported SRH recombination parameters of various common impurities (eg, Fe, Cr, or Ni) were considered. It was found that a dominating role of certain impurities as Cu, Au, Co, or Zn can be excluded. A general simulation study as a function of the fundamental SRH recombination parameters allowed us to reduce the possible SRH parameters significantly in particular of the capture cross‐section ratio of electrons and holes. These results demonstrate that our analysis approach, which combines an experimental variation of wafer thickness and resistivity with a comprehensive device simulation, can provide deep insights into the solar cells loss mechanisms. In particular, the conclusions regarding SRH recombination are of importance for solar cells made of n‐type silicon as there are no meta‐stable impurity states formed that would allow a direct identification of impurity recombination–related power loss as reported for p‐type Si.
Decentralized and adaptive control of multiple nonholonomic robots for sensing coverage
Authors: Abdul Razak Rihab , Srikant Sukumar , Chung Hoam 
Published: January 2018

SummaryThis work deals with decentralized control of multiple nonholonomic mobile sensors for optimal coverage of a given area for sensing purposes. We assume a density function over the region to be covered, which can be viewed as a probability density of the phenomena to be sensed. The density function is unknown but assumed to be linearly parameterized with unknown parameter weights. We consider a second‐order dynamic model for the mobile agents and derive decentralized adaptive control laws to achieve optimal coverage of the region. We then consider the case where the dynamic model of the agents are not fully known, and then develop parameter adaptation laws to achieve the optimal coverage objective. We test the derived algorithms using simulations and compare our proposed controllers with kinematics‐based controllers. We find that the feedback control design based on the dynamic model performs significantly better than controllers solely relying on kinematic models. Furthermore, for the unknown dynamics case, our controller outperforms the nonadaptive controller with poor initial parameter estimates.
Comments on ‘Admissibility and static output‐feedback stabilization of singular Markovian jump systems with defective statistics of modes transitions’
Authors: Vasquez Luis , Chávez‐Fuentes Jorge R. 
Published: January 2018

SummaryThis document shows that the proof of Theorem 3.3 in the work of Liu et al (Int J Robust Nonlinear Control. 2015. 10.1002/rnc.3108) is incorrect and, thus, the theorem is not proved. Since the results of the paper are strongly based on this theorem, the problem has to be addressed. If a natural correction is introduced, the problem still holds. Therefore, a new linear matrix inequality is proposed here to show its equivalence with the stochastic stability of a Markov jump linear singular system under a similar assumption as that in the work of Liu et al.
A DFT study of H2O dissociation on metal‐precovered Fe (100) surface
Authors: Zhang Chuan‐Hui , Chen Bao , Sun Dong‐Bai 
Published: January 2018

The H2O adsorption and dissociation on the Fe (100) surface with different precovered metals are studied by density functional theory. On both kinds of metal‐precovered surface, H2O molecules prefer adsorb on hollow sites than bridge and top sites. The impurity energy difference is proportional to the adsorption energy, but the adsorbates are not sensitive to the adsorption orientation and height relative to the surface. The Hirshfeld charge analysis shows that water molecules act as an electron donor while the surface Fe atoms act as an electron acceptor. The rotation and dissociation of H2O molecule occur on the Co‐ and Mn‐precovered surfaces. Some H2O molecules are dissociated into OH and H groups. The energy barriers are about 0.5 to 1.0 eV, whose are consistence with the experimental data. H2O molecules can be dissociated more easily at the top site on Co‐precovered surface 1 than that at bridge site on Mn‐precovered surface 2 because of the lower reaction barrier. The dispersion correction effects on the energies and adsorption configurations on Co‐precovered surface 1 were calculated by OBS + PW91. The dispersion contributions can improve a bit of the bond energy of adsorbates and weaken the hydrogen bond effect between adsorption molecules a little.
Trimethyl borate‐treated polytetrafluoroethylene micropowders with improved hydrophilic and adhesive properties based on coordination bond theory
Authors: Long XiaoYun , He LiFen , Zhang Yan , Ge Mingqiao 
Published: January 2018

Based on coordination bond theory, the current study proposes a novel method to modify the surface of the polytetrafluoroethylene (PTFE) micropowders. The samples were treated with trimethyl borate in the n‐hexane solution, and this improves the hydrophilic and adhesive properties of PTFE micropowders. The surface properties of treated samples were evaluated by using X‐ray photoelectron spectrometry, contact angle measurement, settling velocity measurement, and adhesive property measurement. Trimethyl borate treatment led to an evident increase in the hydrophilic and adhesive properties of PTFE micropowders. The water contact angle of PTFE micropowders decreased from 115° to 85.4°, while the ethanol contact angle of PTFE micropowders decreased from 39.8° to 11.2° owing to the combination of the trimethyl borate with PTFE micropowders as indicated by the X‐ray photoelectron spectrometry spectra. Furthermore, the settling velocity of powders dispersed in ethanol/water (1/10) solution (pH = 8.5) improved (with a settlement ratio exceeding 20% in 60 minutes), and the fracture stress of the powders/resin composite membrane increased from 4.68 to 6.67 MPa while the elongation at the yield of membrane increased from 25.4% to 31.5%.
Biosynthesis and Characterization of Copper Nanoparticles Using Shewanella oneidensis: Application for Click Chemistry
Authors: Kimber Richard L. , Lewis Edward A. , Parmeggiani Fabio , Smith Kurt , Bagshaw Heath , Starborg Toby , Joshi Nimisha , Figueroa Adriana I. , van der Laan Gerrit , Cibin Giannantonio , Gianolio Diego , Haigh Sarah J. , Pattrick Richard A. D. , Turner Nicholas J. , Lloyd Jonathan R. 
Published: January 2018

AbstractCopper nanoparticles (Cu‐NPs) have a wide range of applications as heterogeneous catalysts. In this study, a novel green biosynthesis route for producing Cu‐NPs using the metal‐reducing bacterium, Shewanella oneidensis is demonstrated. Thin section transmission electron microscopy shows that the Cu‐NPs are predominantly intracellular and present in a typical size range of 20–40 nm. Serial block‐face scanning electron microscopy demonstrates the Cu‐NPs are well‐dispersed across the 3D structure of the cells. X‐ray absorption near‐edge spectroscopy and extended X‐ray absorption fine‐structure spectroscopy analysis show the nanoparticles are Cu(0), however, atomic resolution images and electron energy loss spectroscopy suggest partial oxidation of the surface layer to Cu2O upon exposure to air. The catalytic activity of the Cu‐NPs is demonstrated in an archetypal “click chemistry” reaction, generating good yields during azide‐alkyne cycloadditions, most likely catalyzed by the Cu(I) surface layer of the nanoparticles. Furthermore, cytochrome deletion mutants suggest a novel metal reduction system is involved in enzymatic Cu(II) reduction and Cu‐NP synthesis, which is not dependent on the Mtr pathway commonly used to reduce other high oxidation state metals in this bacterium. This work demonstrates a novel, simple, green biosynthesis method for producing efficient copper nanoparticle catalysts.
Wnt/β-Catenin/TCF Pathway Is a Phase-Dependent Promoter of Colony Formation and Mesendodermal Differentiation During Human Somatic Cell Reprogramming
Authors: Cevallos Ricardo Raúl , Rodríguez-Martínez Griselda , Gazarian Karlen 
Published: January 2018

Abstract
Somatic cell reprogramming is a biphasic phenomenon that goes through a mesenchymal-to-epithelial transition, called initiation phase, followed by a maturation phase wherein reprogramming cells acquire pluripotency. Here, we show that these phases display a differential response to Wnt signaling activation. Wnt signaling increases colony formation by promoting cellular epithelialization during the initiation phase in a TCF7-dependent manner. However, during maturation phase, it is also responsible for inducing mesendodermal differentiation, which is negatively regulated by TCF7L1. Thus, Wnt signaling inhibition or TCF7L1 overexpression downregulates mesendodermal gene expression without perturbing pluripotency. Together, our results demonstrate that a phase-specific modulation of Wnt signaling leads to an improved reprogramming efficiency in terms of colony output and pluripotency acquisition. This work provides new insights into the cell context-dependent roles of Wnt signaling during human somatic cell reprogramming.
Mechanism underlying the effect of long‐term exposure to low dose of pesticides on DNA integrity
Authors: Alleva Renata , Manzella Nicola , Gaetani Simona , Bacchetti Tiziana , Bracci Massimo , Ciarapica Veronica , Monaco Federica , Borghi Battista , Amati Monica , Ferretti Gianna , Tomasetti Marco 
Published: January 2018

AbstractPesticides, including herbicides, insecticides and fungicides, are widely used in intensive agriculture. Recently, the long‐term effects of pesticide exposure were found to be associated with many diseases. In this study, we evaluated the long‐term effect of low‐level exposure to a mixture of pesticides on DNA damage response (DDR) in relation to individual detoxifying variability. A residential population chronically exposed to pesticides was enrolled, biological/environmental pesticide levels; paroxonase 1 (PON‐1) activity and 192 Q/R polymorphism and DDR were evaluated at three different periods of pesticide exposure. OGG1‐dependent DNA repair activity was decreased in relation to pesticide exposure. The increase of DNA lesions and pesticide levels in the intensive pesticide‐spraying period was independent on PON‐1 activity. Next, human bronchial epithelial and neuronal cells were used as a model for in vitro evaluation of the mechanistic effect of pesticides. Pesticides induced mitochondrial dysfunction leading to ROS formation. ROS from mitochondria induced DNA damage, which in turn induced OGG1‐dependent DNA repair activity through 8‐oxoguanine DNA glycosylase 1 (OGG1) expression and activation. Even though OGG1 was overexpressed, an inhibition of its activity, associated with DNA lesion accumulation, was found at prolonged pesticide‐exposure. A post‐translational regulation of OGG1 by pesticide may be postulated. Taken together, long‐term exposure to low‐levels of pesticides affects DDR resulting in accumulation of DNA lesions that eventually may lead to cancer or neurological disorders.
Genetic Counselors’ Experiences and Interest in Telegenetics and Remote Counseling
Authors: Zierhut Heather A. , MacFarlane Ian M. , Ahmed Zahra , Davies Jill 
Published: January 2018

AbstractIn 2009, the National Society of Genetic Counselors Service (NSGC) Delivery Model Task Force defined genetic counseling service delivery models including telephone (genetic counseling provided remotely by telephone) and telegenetics (counseling provided remotely using videoconferencing). Little is known about the experience of genetic counselors practicing telemedicine in the USA. We sought to evaluate perceived satisfaction, advantages, disadvantages, and barriers to the practice and implementation of telegenetics by practicing genetic counselors. A 21‐question online survey was distributed via the NSGC's member directory. Descriptive statistics and a thematic analysis were used to analyze data. A total of 344 surveys were completed of which 235 (68.3%) respondents had delivered genetic counseling via telemedicine and 109 (36.6%) had not. Overall genetic counseling providers who had provided telegenetics were satisfied or very satisfied with their position (91%) and those who were not performing telegenetics were at least slightly interested in a telehealth position (92%).The most common appealing reasons for working in or wanting to work in telemedicine included an innovative approach to healthcare delivery, aspects of remote positions such as the ability to work from home, and flexibility of hours. Unappealing characteristics of telemedicine included the inability to see nonverbals, limited psychosocial counseling, and limited social interaction with colleague that is associated with remote positions. Barriers to implementation of telegenetics were noted by 53% of respondents with the largest barrier being billing and reimbursement. The results of this work suggest that telegenetics service organizations could consider increasing social interactions, attempting to use the preferred method of care (video) to increase ability to see nonverbals, offering flexible work hours, and allowing time to address psychosocial issues as they arise in consultations.
Oligomeric amyloid β preferentially targets neuronal and not glial mitochondrial‐encoded mRNAs
Authors: Mastroeni Diego , Nolz Jennifer , Khdour Omar M. , Sekar Shobana , Delvaux Elaine , Cuyugan Lori , Liang Winnie S. , Hecht Sidney M. , Coleman Paul D. 
Published: January 2018

AbstractIntroductionOur laboratories have demonstrated that accumulation of oligomeric amyloid β (OAβ) in neurons is an essential step leading to OAβ‐mediated mitochondrial dysfunction.MethodsAlzheimer's disease (AD) and matching control hippocampal neurons, astrocytes, and microglia were isolated by laser‐captured microdissection from the same subjects, followed by whole‐transcriptome sequencing. Complementary in vitro work was performed in OAβ‐treated differentiated SH‐SY5Y, followed by the use of a novel CoQ10 analogue for protection. This compound is believed to be effective both in suppressing reactive oxygen species and also functioning in mitochondrial electron transport.ResultsWe report decreases in the same mitochondrial‐encoded mRNAs in Alzheimer's disease laser‐captured CA1 neurons and in OAβ‐treated SH‐SY5Y cells, but not in laser‐captured microglia and astrocytes. Pretreatment with a novel CoQ10 analogue, protects neuronal mitochondria from OAβ‐induced mitochondrial changes.DiscussionSimilarity of expression changes in neurons from Alzheimer's disease brain and neuronal cells treated with OAβ, and the effect of a CoQ10 analogue on the latter, suggests a pretreatment option to prevent OAβ toxicity, long before the damage is apparent.
Pyrethroid and carbamate resistance in Australian Helicoverpa armigera (Lepidoptera: Noctuidae) from 2008 to 2015: what has changed since the introduction of Bt cotton?
Authors: Bird L.J. 
Published: January 2018

AbstractPyrethroid and carbamate resistance was evaluated in Helicoverpa armigera from 2008 to 2015. Insects were collected as eggs primarily from cultivated hosts in the major cropping areas of New South Wales and Queensland, Australia. Larvae reared from eggs were tested for resistance to fenvalerate, bifenthrin or methomyl in the F0 generation using a topical application of a discriminating dose of insecticide. In 2008–2009, resistance to fenvalerate was 71% and no resistance to bifenthrin was recorded. In the following two seasons, resistance to pyrethroids was relatively stable with fenvalerate resistance ranging from 63% to 67% and bifenthrin resistance ranging from 5.6% and 6.4% in 2009–2010 and 2010–2011, respectively. However, in 2011–2012, pyrethroid resistance had increased to 91% and 36% for fenvalerate and bifenthrin, respectively. Resistance remained above 90% for fenvalerate and above 35% for bifenthrin in the following three seasons from 2012 to 2015. In 2008–2009, methomyl resistance was 33% and declined to 22% and 15% in 2009–2010 and 2010–2011, respectively. Methomyl resistance remained at moderate levels from 2011–12 to 2014–15, ranging from 21% to 40%. Factors that influenced selection pressure of pyrethroid and carbamate insecticides and impacted resistance frequency in H. armigera may have been associated with changes in the composition of the cropping landscape. The rapid expansion of the pulse industry and the commensurate increased use of insecticide may have played a role in reselection of high-level pyrethroid resistance, and highlights the need for an urgent and strategic response to insecticide resistance management in the Australian grains industry.
Sensing the ground: On the global politics of satellite-based activism
Authors: Rothe Delf , Shim David 
Published: January 2018

AbstractIn recent years, satellite imagery, previously restricted to the defence and intelligence communities, has been made available to a range of non-state actors as well. Non-governmental organisations, journalists, and celebrities such as George Clooney now use remote sensing data like digital Sherlock Holmeses to investigate and reveal human rights abuses, political violence, environmental destruction, and eco-crimes from a distance. It is often said that the increasing availability and applicability of remote sensing technologies has contributed to the rise of what can be called ‘satellite-based activism’ empowering non-state groups to challenge state practices of seeing and showing. In this article we argue that NGO activism is not challenging the sovereign gaze of the state but, on the contrary, actually reinforcing it. We will bolster our arguments in this regard in two prominent fields of non-governmental remote sensing: human rights and environmental governance.