bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasticizer di(2‐ethylhexyl)phthalate interferes with osteoblastogenesis and adipogenesis in a mouse model
Authors: Chiu Chen‐Yuan , Sun Shih‐Chun , Chiang Chih‐Kang , Wang Ching‐Chia , Chan Ding‐Cheng , Chen Huang‐Jen , Liu Shing‐Hwa , Yang Rong‐Sen 
Published: September 2017

ABSTRACTPlasticizer di(2‐ethylhexyl)phthalate (DEHP) can leach from medical devices such as blood storage bags and the tubing. Recently, epidemiological studies showed that phthalate metabolites levels in the urine are associated with low bone mineral density (BMD) in older women. The detailed effect and mechanism of DEHP on osteoblastogenesis and adipogenesis, and bone loss remain to be clarified. Here, we investigated the effect and mechanism of DEHP and its active metabolite mono(2‐ethylhexyl)phthalate (MEHP) on osteoblastogenesis and adipogenesis. The in vitro study showed that osteoblast differentiation of bone marrow stromal cells (BMSCs) was significantly and dose‐dependently decreased by DEHP and MEHP (10–100 µM) without cytotoxicity to BMSCs. The mRNA expressions of alkaline phosphatase, Runx2, osteocalcin (OCN), Wnt1, and β‐catenin were significantly decreased in DEHP‐ and MEHP‐treated BMSCs during differentiation. MEHP, but not DEHP, significantly increased the adipocyte differentiation of BMSCs and PPARγ mRNA expression. Both DEHP and MEHP significantly increased the ratios of phosphorylated β‐catenin/β‐catenin and inhibited osteoblastogenesis, which could be reversed by Wnt activator lithium chloride and PPARγ inhibitor T0070907. Moreover, exposure of mice to DEHP (1, 10, and 100 mg/kg) for 8 weeks altered BMD and microstructure. In BMSCs isolated from DEHP‐treated mice, osteoblastogenesis and Runx2, Wnt1, and β‐catenin expression were decreased, but adipogenesis and PPARγ expression were increased. These findings suggest that DEHP and its metabolite MEHP exposure may inhibit osteoblastogenesis and promote adipogenesis of BMSCs through the Wnt/β‐catenin‐regulated and thus triggering bone loss. PPARγ signaling may play an important role in MEHP‐ and DEHP‐induced suppression of osteogenesis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1124–1134, 2018.
Ultrafast Material Processing with High‐Brightness Fiber Lasers
Authors: Streek André , Lee Michael 
Published: September 2017

AbstractMachine tool builders demand cost reductions in many material laser processing applications like additive manufacturing, thin film ablation, surface structuring, cleaning, and foil cutting. All markets lead laser and optoelectronic component suppliers in the same way to improve the throughput as well as yield of available laser power. A feasible way of achieving cost reductions is to use existing machine components and upgrade the laser power as well as deploying advanced scanning technology in order to get five to ten times better throughput. Therefore, they improve cost per part or cost per hour massively.
The Incredible Additive Manufacturing Creates Movement
Authors: Hanreich Klaus 
Published: September 2017

AbstractAt a first glance, additive manufacturing seems to be a very simple manufacturing process. Nevertheless, many companies are not happy with their adaption of this new technology or are even overburdened by it. Often, we have to undisputedly agree with these companies. However, we can change their opinions straight away. The fascinating metal 3D printing nowadays even manages to print moving objects without needing assembly afterwards. Even though it seems hard to believe, it surely is possible with suitable handling and application. But has that always been this way?
Spatiotemporal distribution and microbial assimilation of polyamines in a mesotrophic lake
Authors: Krempaska Natalia , Horňák Karel , Pernthaler Jakob 
Published: September 2017

AbstractWe examined seasonal and spatial variations of dissolved free polyamines (DFPA) in the large mesotrophic prealpine Lake Zurich (Switzerland). An ion‐pairing liquid chromatography method with mass spectrometric detection was optimized for the quantification of DFPA without prior concentration or derivatization. Total DFPA concentrations varied between 0.4 nM and 11 nM in winter and spring of 2015, respectively. Polyamine concentrations were highest in the epilimnion during the phytoplankton growth phase, and reflected occurrence patterns of diatoms. Putrescine consistently dominated the DFPA pool throughout the season whereas norspermidine was detected only once in spring. Incubations with 13C‐labeled putrescine revealed concentration‐dependent uptake rates (3.2–5 nM h−1) and short turnover times (2.4–4.4 h). In contrast, incorporation rates into biomass measured with 14C‐labeled putrescine were substantially lower (0.9 nM h−1), indicating that this compound was predominantly respired. Uptake kinetics moreover suggested that putrescine in situ uptake rates were limited by low ambient concentrations. Competition assays revealed that putrescine uptake could only be inhibited by excess concentrations of another polyamine (spermidine), but not by amino acids. Bacteria affiliated with Limnohabitans and the acI lineage of Actinobacteria were identified as the taxa with the highest fraction (25–32%) of putrescine‐incorporating cells. This compound was also utilized by Alphaproteobacteria, Cyclobacteriaceae, diatoms, and cyanobacteria. Overall, our data point to fast turnover of putrescine by different microorganisms, implying the importance of this substrate as an attractive energy source.
Poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) Modification via Organocatalyzed Atom Transfer Radical Polymerization
Authors: Hu Xin , Zhang Yajun , Cui Guopeng , Zhu Ning , Guo Kai 
Published: September 2017

AbstractTo address the challenge of metal contamination, a “graft from” approach via organocatalyzed atom transfer radical polymerization (O‐ATRP) is developed to synthesize poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) (P(VDF‐co‐CTFE)) graft copolymers. N‐phenylphenothiazine is utilized as a model organic photoredox catalyst for catalyzing the (co)polymerization of methyl methacrylate (MMA), methacrylate (MA), and n‐butyl acrylate (BA). By employing this technique, high temporal control of polymerization and graft content are achieved. A series of P(VDF‐co‐CTFE)‐g‐PMMA, P(VDF‐co‐CTFE)‐g‐PMA, and P(VDF‐co‐CTFE)‐g‐PBA is prepared under mild conditions. The resultant graft copolymer can be used as macroinitiator to re‐initiate O‐ATRP to synthesize P(VDF‐co‐CTFE)‐g‐(PMMA‐b‐PMA), which might exhibit the potential application as novel dielectric material.
Evaluation of several soft computing methods in monthly evapotranspiration modelling
Authors: Gavili Siavash , Sanikhani Hadi , Kisi Ozgur , Mahmoudi Mohammad Hasan 
Published: September 2017

ABSTRACTEvapotranspiration assessment is one of the most substantial issues in hydrology. The methods used in modelling reference evapotranspiration (ET0) consist of empirical equations or complex methods based on physical processes. In arid and semi‐arid climates, determining the amount of evapotranspiration has a major role in the design of irrigation systems, irrigation network management, planning and management of water resources and water management issues in the agricultural sector. This paper presents a case study of five meteorological stations located in Kurdistan province in the west of Iran. The ability of three different soft computing methods, an artificial neural network (ANN), an adaptive neuro‐fuzzy inference system (ANFIS) and gene expression programming (GEP), were compared for modelling ET0 in this study. The FAO56 Penman−Monteith model was considered as a reference model and soft computing models were compared using the Priestley−Taylor, Hargreaves, Hargreaves−Samani, Makkink and Makkink−Hansen empirical methods, with respect to the determination co‐efficient, the root mean square error, the mean absolute error and the Nash–Sutcliffe model efficiency co‐efficient. Soft computing models were superior to the empirical methods in modelling ET0. Among the soft computing methods, the ANN was found to be better than the ANFIS and GEP.
Integrating prior information into microwave tomography part 2: Impact of errors in prior information on microwave tomography image quality
Authors: Kurrant Douglas , Fear Elise , Baran Anastasia , LoVetri Joe 
Published: September 2017

PurposeThe authors have developed a method to combine a patient‐specific map of tissue structure and average dielectric properties with microwave tomography. The patient‐specific map is acquired with radar‐based techniques and serves as prior information for microwave tomography. The impact that the degree of structural detail included in this prior information has on image quality was reported in a previous investigation. The aim of the present study is to extend this previous work by identifying and quantifying the impact that errors in the prior information have on image quality, including the reconstruction of internal structures and lesions embedded in fibroglandular tissue. This study also extends the work of others reported in literature by emulating a clinical setting with a set of experiments that incorporate heterogeneity into both the breast interior and glandular region, as well as prior information related to both fat and glandular structures.MethodsPatient‐specific structural information is acquired using radar‐based methods that form a regional map of the breast. Errors are introduced to create a discrepancy in the geometry and electrical properties between the regional map and the model used to generate the data. This permits the impact that errors in the prior information have on image quality to be evaluated. Image quality is quantitatively assessed by measuring the ability of the algorithm to reconstruct both internal structures and lesions embedded in fibroglandular tissue. The study is conducted using both 2D and 3D numerical breast models constructed from MRI scans.ResultsThe reconstruction results demonstrate robustness of the method relative to errors in the dielectric properties of the background regional map, and to misalignment errors. These errors do not significantly influence the reconstruction accuracy of the underlying structures, or the ability of the algorithm to reconstruct malignant tissue. Although misalignment errors do not significantly impact the quality of the reconstructed fat and glandular structures for the 3D scenarios, the dielectric properties are reconstructed less accurately within the glandular structure for these cases relative to the 2D cases. However, general agreement between the 2D and 3D results was found.ConclusionA key contribution of this paper is the detailed analysis of the impact of prior information errors on the reconstruction accuracy and ability to detect tumors. The results support the utility of acquiring patient‐specific information with radar‐based techniques and incorporating this information into MWT. The method is robust to errors in the dielectric properties of the background regional map, and to misalignment errors. Completion of this analysis is an important step toward developing the method into a practical diagnostic tool.
Metabolic assessment of a migraine model using relaxation‐enhanced 1H spectroscopy at ultrahigh field
Authors: Abad Nastaren , Rosenberg Jens T. , Roussel Tangi , Grice Dillon C. , Harrington Michael G. , Grant Samuel C. 
Published: September 2017

PurposeThis study evaluates biochemical imbalances in a rat model that reflects dysfunctional pathways in migraine. The high sensitivity and spectral dispersion available to 1H MRS at 21.1 T expands metabolic profiling in this migraine model to include lactate (Lac), taurine (Tau), aspartate, and Gly—a mixture of glycine, glutamine, and glutamate.MethodsSprague‐Dawley male rats were administered in situ an intraperitoneal injection of nitroglycerin (NTG) to induce the migraine analogue or saline as a control. A selective relaxation‐enhanced MR spectroscopy sequence was used to target upfield metabolites from a 4‐mm3 voxel for 2.5 h after injection.ResultsSignificant increases were evident for Lac as early as 10 min after NTG injection, peaking over 50% compared with baseline and control (normalized Lac/N‐acetyl aspartate with NTG = 1.54 ± 0.65 versus with saline = 0.99 ± 0.08). Tau decreased progressively in controls over 2 h after injection, but remained elevated with NTG, peaking at 105 min after injection (normalized Tau/N‐acetyl aspartate with NTG = 1.10 ± 0.18 versus with saline = 0.85 ± 0.14). Total creatine under NTG showed significant decreases with time and compared with saline; Gly demonstrated temporal increases for NTG.ConclusionsThese changes indicate an altered metabolic profile in the migraine analogue consistent with early changes in neural activity and/or vasodilation consistent with progressively enhanced neuroprotection and osmoregulation. Magn Reson Med 79:1266–1275, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Exploring the influence of acceptor content on semi‐random conjugated polymers
Authors: Ekiz Seyma , Gobalasingham Nemal S. , Thompson Barry C. 
Published: September 2017

ABSTRACTA family of diketopyrrolopyrrole (DPP)‐incorporated P3HT based semi‐random copolymers was synthesized and their optical, electronic and photovoltaic properties were investigated. For the first time, the influence of acceptor content on semi‐random copolymers was explored in the broad range of 10–40% acceptor. A mixture of DPP acceptor units with different side chains (ethylhexyl and decyltetradecyl) was incorporated into each copolymer to improve solubility and film quality. Increased DPP content in the polymer backbone resulted in broadened absorption between 350 and 900 nm, resulting in a monotonic decrease in optical band gap (Eg) of the polymers from 1.49 to 1.37 eV. Highest occupied molecular orbital (HOMO) energy levels showed an increase from 10% DPP to 20–30% DPP, while decreasing for 40% DPP. Voc values followed a consistent trend with HOMO energy levels. Semi‐random copolymers showed significantly improved photovoltaic properties compared with P3HT. Bulk heterojunction solar cells fabricated from the semi‐random copolymers blended with PC61BM exhibited high short‐circuit current densities (Jsc) up to 10.29 mA/cm2 and efficiencies up to 4.43%. A new method of methanol treatment was developed and applied to the semi‐random copolymers resulting in high fill factors approaching 0.70 under ambient conditions. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3884–3892
Mitigating chain‐transfer and enhancing the thermal stability of co‐based olefin polymerization catalysts through sterically demanding ligands
Authors: Mitchell Nolan E. , Anderson W. Curtis , Long Brian K. 
Published: September 2017

ABSTRACTSterically demanding Fe‐ and Co‐based olefin polymerization catalysts 2‐Fe and 2‐Co bearing 2,6‐bis(biphenylmethyl)‐4‐methylaniline substituted bis(imino)pyridine ligands were synthesized and evaluated for ethylene polymerization. The late‐transition metal complexes were characterized by X‐ray diffraction, NMR spectroscopy, and HRMS, while their resultant polymers were characterized by size‐exclusion chromatography and 1H NMR spectroscopy. While catalyst 2‐Fe was inactive, catalyst 2‐Co was found to polymerize ethylene and avoid any detectable chain‐transfer to aluminum events that are known to plague other Fe‐ and Co‐based catalyst systems and to limit molecular weight. Furthermore, 2‐Co displays virtually perfect thermal stability up to 80 °C and shows greatly enhanced thermal stability at 90 °C as compared to previously reported analogues. These observations are attributed to the extreme steric demand imposed by the ligand which mitigates catalyst transfer, deactivation, and decomposition reactions. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3990–3995
Estimate your dose: RADDOSE‐3D
Authors: Bury Charles S. , Brooks‐Bartlett Jonathan C. , Walsh Steven P. , Garman Elspeth F. 
Published: September 2017

AbstractWe present the current status of RADDOSE‐3D, a software tool allowing the estimation of the dose absorbed in a macromolecular crystallography diffraction experiment. The code allows a temporal and spatial dose contour map to be calculated for a crystal of any geometry and size as it is rotated in an X‐ray beam, and gives several summary dose values: among them diffraction weighted dose. This allows experimenters to plan data collections which will minimize radiation damage effects by spreading the absorbed dose more homogeneously, and thus to optimize the use of their crystals. It also allows quantitative comparisons between different radiation damage studies, giving a universal “x‐axis” against which to plot various metrics.
Adaptive synchronization control design for flexible telerobotics with actuator fault and input saturation
Authors: Yang Y. , Li J. , Hua C. , Guan X. 
Published: September 2017

SummaryThis paper addresses the synchronization control problem of flexible telerobotics with actuator fault, input saturation, and asymmetrical time‐varying delays. A new adaptive antisaturation nonlinear fractional power proportional+damping fault‐tolerant control scheme is designed. With the new control algorithm, faster convergence rate and higher convergence precision can be guaranteed, as compared with the general proportion+damping control method. By choosing Lyapunov‐Krasovskii functional, it shows that the teleoperation system is stable under specific linear matrix inequality conditions. Thus, the allowable maximal transmission delay can be computed with the given controller‐design parameters. To validate the effectiveness of the proposed method, simulations on synchronization control system composed of 2 manipulators (master is rigid, and slave is flexible) are developed. Experiments on the PHANToM Premium 1.5A manipulators are also conducted and numerous experimental results are presented to show the superior performance of the proposed control scheme.
Effects of Carbon Content on the Lithium‐Storage Properties of MoSe2‐C Nanocomposites
Authors: Wu Laidi , Tan Pengfei , Liu Yi , Xiong Xiang , Pan Jun 
Published: September 2017

AbstractMoSe2 has the genuine potential as anode material for lithium‐ion batteries, benefiting from its layered structure, large interlayer space and high specific capacity. In this work, we achieve the controllable and in‐situ synthesis of MoSe2‐C nanocomposites and investigating the dimensional effects (grain size, interlayer distance, and slabs of stacking in number) of carbon content on the MoSe2‐C hybrid material. The optimized anode MoSe2‐15.0%C delivers prominent cycling performance (a high reversible capacity of 1165 mAh g−1 after 150 cycles at 0.2 A g−1 and 860 mAh g−1 after 150 cycles at 1 A g−1) and compelling rate behavior (734 mAh g−1 even at a current density of as high as 10 A g−1). The above elucidates that the modest carbon layer not only guarantee the integrity of the electrode by avoiding the structure collapse, but also elevate the electric conductivity to supply quick discharging and charging. The outstanding electrochemical performance is attributed to the synergistic effect between MoSe2 and the carbon. Hence, MoSe2‐C nanocomposites could be deemed as promising anode materials in lithium‐ion batteries.
Reversible Structural Phase Transition and Dielectric Switches Induced by Disordering‐Ordering Motion of Tetrachloroferrate (III) Anions
Authors: Tang Yun‐Zhi , Wang Chang‐Feng , Chen Shao‐Peng , Tan Yu‐Hui , Yang Chang‐Shan , Bin‐Wang  , Wen He‐Rui 
Published: September 2017

AbstractReversible phase transitions triggered by guest AX4 type metal structural anions such as AuCl4−, FeCl4− etc are sparely documented before. Here we reported a host–guest clathrate, 18‐crown‐6 potassium tetrachloroferrate, [K2(C12H24O6)]2+⋅[FeCl4]22–(1) which exhibits reversible phase transition around 135 K. This special phase transition behaviours were further confirmed by the heat and dielectric anomalies in the vicinity of 135 K. The structural transition mechanism can be attributed to the ordering‐disordering motion of the tetrachloroferrate anions. Its switchable dielectric behaviours around the phase transition point suggest it maybe a potential material for dielectric switches.
Toward a dynamic notion of value creation and appropriation in firms: The concept and measurement of economic gain
Authors: Lieberman Marvin B. , Balasubramanian Natarajan , Garcia‐Castro Roberto 
Published: September 2017

Research Summary: “Value creation” is central to strategy. Even so, confusion arises because it can be defined in different ways, e.g., as the sum of producer and consumer surplus in a given time period, or as the change in surplus over time. To formalize the latter notion, we introduce the concept of economic gain, defined as the increase in total surplus. Economic gain can arise through innovation or when a superior firm displaces competitors. We provide a firm‐level measurement framework to quantify economic gain and its distribution among stakeholders, including the firm's shareholders, employees, suppliers, and customers. As an empirical illustration, we compare the creation and distribution of economic gain by Southwest Airlines and American Airlines between 1980 and 2010.
Managerial Summary: Most managers and the business press regard “value creation” as the increase in shareholder wealth represented by a rise in corporate profit or stock price. A broader conception of value creation goes beyond shareholders to include the value that is distributed to additional stakeholders of the firm, including employees, suppliers, and customers. We develop a mathematical framework that allows this broader notion of value creation and distribution to be assessed and quantified in many cases. We illustrate the framework using historical data on Southwest Airlines and American Airlines over 3 decades.
Capabilities, technologies, and firm exit during industry shakeout: Evidence from the global solar photovoltaic industry
Authors: Furr Nathan , Kapoor Rahul 
Published: September 2017

Research Summary: Explanations of entrants’ survival in an emerging industry are premised on pre‐entry capabilities or technology entry choices prior to the emergence of the dominant design. We consider how these drivers interact to strengthen or nullify firms’ pre‐entry advantage, and facilitate adaptation as the industry evolves. We also expand the treatment of exit by separating dissolution from acquisition, in which firms’ capabilities continue to be utilized in the industry. Studying a recent shakeout in the global solar photovoltaic industry, we find that pre‐entry capabilities and technology choices act in a complementary manner for some firms, thereby enhancing survival, and as buffers against exit for others. Nearly half of exits were via acquisitions, and technology choice at entry played an important role in determining how firms exited.
Managerial Summary: New industries are often characterized by intense technology competition that culminates in a dominant technology followed by industry shakeout. Although prior research underscores the central role of technology choice and firm capabilities to survival, we do not actually know how firms with different capabilities and who have made competing technology choices survive an industry shakeout. In this article, we show how entrants’ capabilities and technology choices can act in a complementary manner for some firms, enhancing their chance of survival, and as buffers against failure for others. Moreover, we explain why some firms that do exit are acquired, when others are dissolved.