bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intra‐seasonal rainfall variability in the Amazon basin related to large‐scale circulation patterns: a focus on western Amazon–Andes transition region
Authors: Paccini Laura , Espinoza Jhan Carlo , Ronchail Josyane , Segura Hans 
Published: November 2017

ABSTRACTThis study aims to relate the intra‐seasonal rainfall variability over the Amazon basin to atmospheric circulation patterns (CPs), with particular attention to extreme rainfall events in the Amazon–Andes region. The CPs summarize the intra‐seasonal variability of atmospheric circulation and are defined using daily low‐level winds from the ERA‐Interim (1.5° × 1.5°) reanalysis for the 1979–2014 period. Furthermore, observational data of precipitation and high‐resolution TRMM 3B42 (∼25 km), 2A25 PR (∼5 km) and CHIRPS (∼5 km) data products are related to the CPs throughout the Amazon basin. Nine CPs are determined using a hybrid method that combines a neural network technique (self‐organizing maps, SOM) and hierarchical ascendant classification. The CPs are characterized by a specific cycle with alternative transitions and a duration of 14 days on average. This configuration initially results in northerly winds to southerly winds towards the northern or eastern Amazon basin. The related rainfall suggests that it is driven mainly by CP dynamics. In addition, we demonstrate a good agreement amongst the four rainfall data sets: observed precipitation, TRMM 3B42, TRMM 2A25 PR and CHIRPS. Furthermore, special attention is given to the Amazon–Andes transition region. Over this region, two particular CPs (CP4 and CP5) are identified as the key contributors of maximum and minimum daily rainfall, respectively. Thus, during the dry season, 40.8% (11.4%) of the CP5 (CP4) days demonstrate rainfall of less than 1 mm day−1, while during the wet season, 6.2% (14.6%) of the CP5 (CP4) days show rainfall amounts higher than the seasonal 90th percentile (10.4 mm day−1). This study provides additional information concerning the intra‐seasonal circulation variability in Amazonia and demonstrates the value of using remote sensing precipitation data in this region as a tool for forecast in areas lacking observable information.
Powder on Demand
Authors: Dickler Harald , Tharmakulasingam Sadagopan 
Published: November 2017

AbstractThe use of a Rapid‐Powder‐Switch (RPS) during laser metal deposition leads to powder savings of up to fifty percent: With a short switching cycle of less than 200 ms, the powder is immediately available between processing cycles. Thus, surfaces can be coated precisely and only where required – efficient and resource‐conserving.
CO2 Laser‐Based Fiber Splicing System
Authors: Theeg Thomas 
Published: November 2017

AbstractThe outstanding spatial and temporal flexibility and precise control of a laser beam enable automated, reliable and individualized production of single‐ and multi‐mode fiber components. These components can be used for fiber lasers and amplifiers, fiber‐coupled diode lasers and fiber‐based beam delivery systems. The cost‐efficient customization of fiber components is important for the support of the wide range of laser wavelengths and fiber types used for different applications in the laser market. In the following sections, this will be representatively described for our CO2 laser‐based fiber splicing system, which is made for individual fiber splicing tasks using large optical elements such as fiber end caps.
Unbinding of Kinesin from Microtubule in the Strongly Bound States Enhances under Assisting Forces
Authors: Khataee Hamidreza , Naseri Solmaz , Zhong Yongmin , Liew Alan Wee‐Chung 
Published: November 2017

AbstractThe ability to predict the cellular dynamics of intracellular transport has enormous potential to impact human health. A key transporter is kinesin‐1, an ATP‐driven molecular motor that shuttles cellular cargos along microtubules (MTs). The dynamics of kinesins depends critically on their unbinding rate from MT, which varies depending on the force direction applied on the motor, i.e. the force‐unbinding rate relation is asymmetric. However, it remains unclear how changing the force direction from resisting (applied against the motion direction) to assisting (applied in the motion direction) alters the kinesin's unbinding and stepping. Here, we propose a theoretical model for the influence of the force direction on the stepping dynamics of a single kinesin. The model shows that the asymmetry of the force‐unbinding rate relation is independent of ATP concentration. It also reveals that the synthesis of ATP from backward stepping under assisting forces is less likely than under resisting forces. It then finds that the unbinding of kinesin in the strongly MT‐bound kinetic states enhances under assisting forces.
A kit ligand, stem cell factor as a possible mediator inducing overactive bladder
Authors: Kubota Yasue , Hamakawa Takashi , Osaga Satoshi , Okada Atsushi , Hamamoto Shuzo , Kawai Noriyasu , Kohri Kenjiro , Yasui Takahiro 
Published: November 2017

ObjectiveTo investigate whether c‐kit ligand, stem cell factor (SCF) affects the biological behavior of overactive bladder (OAB) and discuss the role of SCF as a possible mediator inducing OAB.Materials and methodsFirst, we performed an immunohistochemical study to examine the localization of SCF in the guinea pig and human bladder. Next, urinary SCF levels were measured in patients with OAB and in control subjects to evaluate a potential biomarker for the diagnosis of OAB. Third, we examined the effect of SCF administration on the urinary bladder using guinea pigs to obtain additional information about SCF. The animals were administered with mouse SCF, and cystometry was performed. The following urodynamic parameters were analyzed: inter‐contraction interval, maximum voiding pressure, pressure threshold, detrusor baseline pressure, and the number of non‐voiding contractions.ResultsImmunohistochemical study showed that the expression of SCF was observed throughout the bladder wall, but especially in the urothelium of guinea pig and human bladder. Medians and IQRs of urinary SCF and SCF/creatinine levels in OAB patients (85.9 pg/mL [42.8, 199.0] and 1.30 [0.56, 2.71], respectively) were significantly higher than in control subjects (18.9 pg/mL [5.0, 43.6] and 0.26 [0.13, 0.43], respectively). SCF administration dose‐dependently shortened the intercontraction interval and an increased number of non‐voiding contractions (P < 0.05).ConclusionsOur present data suggest that SCF produced in the urinary bladder may act as a possible mediator by binding to c‐kit, which is expressed in ICC‐like cells in the suburothelial and muscle layers, to control bladder function.
Green and Red Fluorescent Dyes for Translational Applications in Imaging and Sensing Analytes: A Dual‐Color Flag
Authors: Oliveira Elisabete , Bértolo Emilia , Núñez Cristina , Pilla Viviane , Santos Hugo M. , Fernández‐Lodeiro Javier , Fernández‐Lodeiro Adrian , Djafari Jamila , Capelo José Luis , Lodeiro Carlos 
Published: November 2017

AbstractRed and green are two of the most‐preferred colors from the entire chromatic spectrum, and red and green dyes are widely used in biochemistry, immunohistochemistry, immune‐staining, and nanochemistry applications. Selective dyes with green and red excitable chromophores can be used in biological environments, such as tissues and cells, and can be irradiated with visible light without cell damage. This critical review, covering a period of five years, provides an overview of the most‐relevant results on the use of red and green fluorescent dyes in the fields of bio‐, chemo‐ and nanoscience. The review focuses on fluorescent dyes containing chromophores such as fluorescein, rhodamine, cyanine, boron–dipyrromethene (BODIPY), 7‐nitobenz‐2‐oxa‐1,3‐diazole‐4‐yl, naphthalimide, acridine orange, perylene diimides, coumarins, rosamine, Nile red, naphthalene diimide, distyrylpyridinium, benzophosphole P‐oxide, benzoresorufins, and tetrapyrrolic macrocycles. Metal complexes and nanomaterials with these dyes are also discussed.
Quantitation of Tolyporphins, Diverse Tetrapyrrole Secondary Metabolites with Chlorophyll‐Like Absorption, from a Filamentous Cyanobacterium–Microbial Community
Authors: Zhang Yunlong , Zhang Ran , Hughes Rebecca‐Ayme , Dai Jingqiu , Gurr Joshua R. , Williams Philip G. , Miller Eric S. , Lindsey Jonathan S. 
Published: November 2017

AbstractIntroductionTolyporphins are unusual tetrapyrrole macrocycles produced by a non‐axenic filamentous cyanobacterium (HT‐58‐2). Tolyporphins A–J, L, and M share a common dioxobacteriochlorin core, differ in peripheral substituents, and exhibit absorption spectra that overlap that of the dominant cyanobacterial pigment, chlorophylla. Identification and accurate quantitation of the various tolyporphins in these chlorophyll‐rich samples presents challenges.ObjectiveTo develop methods for the quantitative determination of tolyporphins produced under various growth conditions relative to that of chlorophylla.MethodologyChromatographic fractionation of large‐scale (440 L) cultures afforded isolated individual tolyporphins. Lipophilic extraction of small‐scale (25 mL) cultures, HPLC separation with an internal standard, and absorption detection enabled quantitation of tolyporphin A and chlorophylla, and by inference the amounts of tolyporphins A–M. Absorption spectroscopy with multicomponent analysis of lipophilic extracts (2 mL cultures) afforded the ratio of all tolyporphins to chlorophylla. The reported absorption spectral data for the various tolyporphins required re‐evaluation for quantitative purposes.Results and DiscussionThe amount of tolyporphin A after 50 days of illumination ranged from 0.13 nmol/mg dry cells (media containing nitrate) to 1.12 nmol/mg (without nitrate), with maximum 0.23 times that of chlorophylla. Under soluble‐nitrogen deprivation after 35–50 days, tolyporphin A represents 1/3–1/2 of the total tolyporphins, and the total amount of tolyporphins is up to 1.8‐fold that of chlorophylla.ConclusionsThe quantitative methods developed herein should facilitate investigation of the biosynthesis of tolyporphins (and other tetrapyrroles) as well as examination of other strains for production of tolyporphins. Copyright © 2017 John Wiley & Sons, Ltd.
Toxic metals in amniotic fluid and altered gene expression in cell‐free fetal RNA
Authors: Smeester Lisa , Martin Elizabeth M. , Cable Pete , Bodnar Wanda , Boggess Kim , Vora Neeta L. , Fry Rebecca C. 
Published: November 2017

AbstractBoth exposures to toxic metals, as well as deficiencies in essential metals, during pregnancy has been linked to a variety of negative reproductive outcomes. The exact etiologies of such outcomes and the effects of fetal exposure to these metals are largely unknown. Therefore, the ability to assess levels of these elements is critical to determining the underlying causes of such conditions and the effects that both essential and nonessential metals have on fetal development. Thus, using cell‐free fetal RNA from amniotic fluid, we set out to measure the association between amniotic fluid levels of toxic and essential metals and fetal gene expression. We find that arsenic was associated with increased expression of 3 genes known to play roles in both birth‐related and reproductive effects. The results highlight the potential for detrimental health effects of prenatal metals exposure and the potential to identify biomarkers of environmental exposure during this critical developmental period.
Synthesis and electrochemical evaluation of 2‐substituted imidazolium salts
Authors: Hogan David T. , Sutherland Todd C. 
Published: November 2017

AbstractHerein, we report the synthesis, electrochemical, and computational evaluation of six 2‐substituted imidazolium bromides and six 2‐substituted imidazolium triflates. All final compounds were obtained in 2 or fewer synthetic steps from inexpensive starting materials and display a single, irreversible electrochemical reduction. The reduction potentials span a range greater than 1 V depending on the electron withdrawing power of the 2‐substituent. Imidazolium bromides such as Bn2(H)ImBr reduce with E1/2 = −2.70 V vs Fc/Fc+, whereas the electron‐withdrawing Br‐containing analog Bn2(Br)ImBr reduces at only −1.58 V vs Fc/Fc+. The reduction potential of imidazolium bromides obeys a linear free energy relationship to σm Hammett constants, whereas imidazolium triflates correlate better with the σp Hammett constants. These results indicate that the stabilizing effect of the 2‐substituent is anion‐sensitive, changing from induction to resonance upon exchanging bromide for triflate. Predicted electron affinities from density functional theory–optimized structures of imidazolium cations and reduced species more closely match experimental data for the triflates, suggesting that a triflate anion does not electronically perturb the imidazolium core as much as a bromide. Taken together, these data highlight the dual modularity of imidazolium salts by changing both 2‐substituent and anion.
Modulation of immunogenicity of poly(sarcosine) displayed on various nanoparticle surfaces due to different physical properties
Authors: Kim Cheol Joo , Hara Eri , Watabe Naoki , Hara Isao , Kimura Shunsaku 
Published: November 2017

Poly(sarcosine) displayed on polymeric micelle is reported to trigger a T cell‐independent type2 reaction with B1a cells in the mice to produce IgM and IgG3 antibodies. In addition to polymeric micelle, three kinds of vesicles displaying poly(sarcosine) on surface were prepared here to evaluate the amounts and avidities of IgM and IgG3, which were produced in mice, to correlate them with physical properties of the molecular assemblies. The largest amount of IgM was produced after twice administrations of a polymeric micelle of 35 nm diameter (G1). On the other hand, the production amount of IgG3 became the largest after twice administrations of G3 (vesicle of 229 nm diameter) or G4 (vesicle of 85 nm diameter). The augmented avidity of IgG3 after the twice administrations compared with that at the single administration was the highest with G3. These differences in immune responses are discussed in terms of surface density of poly(sarcosine) chains, nanoparticle size, hydrophobic component of poly(L‐lactic acid) or (Leu‐ or Val‐Aib)n, and membrane elasticity of the nanoparticles. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.
Benchmarking of DFT functionals for the kinetics and mechanisms of atmospheric addition reactions of OH radicals with phenyl and substituted phenyl‐based organic pollutants
Authors: Ma Fangfang , Xie Hong‐Bin , Chen Jingwen 
Published: November 2017

Abstract•OH addition reactions play a pivotal role in the atmospheric transformation of a number of phenyl and substituted phenyl‐based persistent and toxic organic pollutants. Here, we screened appropriate DFT functionals to predict reaction mechanisms and rate constants (kOH) of the •OH additions by taking benzene and substituted benzenes (C6H5F, C6H5Cl, C6H5Br, C6H5CH3, C6H5OH) as model compounds. By comparing the kOH values calculated with DFT methods to experimental values, we found that the ωB97 functional is the best among the 18 functionals considered (using the basis sets 6‐31 + G(d,p) for optimizations and 6‐311++G(3df,2pd) for single point energy calculations) in the temperature range of 230‐330 K. In addition, we found that some other functionals performed well in specific conditions, e.g., BMKD3 is good for benzene, halogenated benzenes and C6H5CH3, and CAM‐B3LYP is good for the reaction of C6H5OH at room temperature. Based on the diversity of the electronic structures of the selected model compounds and the frequent occurrence of certain substituents (CH3, OH, F, Cl, and Br) in the target compounds, the functionals recommended here can be used for future study of the reaction mechanisms and kOH values for •OH addition to phenyl and substituted phenyl‐based persistent and toxic organic pollutants.
Creating and capturing value from freemium business models: A demand‐side perspective
Authors: Rietveld Joost 
Published: November 2017

Research Summary: While it has long been recognized that the business model can be a source of performance heterogeneity, less is known about how the business model affects consumers' perceptions about a firm's products and services. By taking a demand‐side perspective, I argue that business models create and capture value when the elements that compose a business model improve how consumers perceive a firm's products and better enable heterogeneous consumers to act on their willingness‐to‐pay. I develop theory on how the freemium business model competes with the premium business model and test hypotheses in the market for digital PC games. Results show that freemium games are played less and generate less revenues and that greater variety in games' menus of paid items is associated with higher revenues.
Managerial Summary: Freemium business models are increasingly prevalent in the digital economy, yet very little is known about how freemium affects consumers' perceptions of value and their willingness‐to‐pay. In this article, I study how the freemium business model competes with the premium business model in the market for digital PC games. Results show that freemium games are played less and generate less revenues than premium games and that greater variety in games' menus of paid items is associated with higher revenues. This implies that in order to achieve competitive parity with firms operating the premium business model, firms operating the freemium business model need to create more value (e.g., through improved product quality, income from advertisements, or unlocking network externalities) or operate at lower costs.
Self‐selection of entrepreneurial firms in thin venture capital markets: Theory and empirical evidence
Authors: Bertoni Fabio , D'Adda Diego , Grilli Luca 
Published: November 2017

Research Summary: We develop a two‐step selection model between entrepreneurial ventures and venture capital (VC) investors in a thin VC market. The model predicts that in a thin VC market, the availability of VC reduces the propensity of firms to self‐select into the market for VC (demand‐side selection) but not the probability that firms entering the market for VC will receive financing (supply‐side selection). We test these predictions using survey‐based data on 190 new technology‐based firms in Italy during the late 1990s and early 2000s. The empirical evidence supports the predictions of the model.Managerial Summary: Venture capital (VC) is an important ingredient of an environment that is conducive to the birth and the growth of entrepreneurial ventures, but VC markets are often highly local and thin in terms of participants. We show that the scarcity of VC supply may cause a drop in the demand for VC because entrepreneurs, anticipating that competition for VC money will be tough, will not seek VC in the first place. The more a market is thin, the more the demand‐side selection is likely to become more important than the supply‐side selection of VC investors. Demand‐side selection may involve a significant number of otherwise good targets for VC investment, which will not be in the radar of VC investors. In turn, this may deter new VC investors from entering the local market, thus creating a vicious cycle that raises concerns for both policy makers and VC general partners.
Accelerator expertise: Understanding the intermediary role of accelerators in the development of the Bangalore entrepreneurial ecosystem
Authors: Goswami Ketan , Mitchell J. Robert , Bhagavatula Suresh 
Published: November 2017

Research Summary: To understand the intermediary role of accelerators in the developing regional entrepreneurial ecosystem of Bangalore, we analyze data from 54 interviews with accelerator graduates, accelerator managers, and other ecosystem stakeholders and from 49 websites, 13 online video interviews, 26 online news sources, and 301 pages of policy documents. Specifically, we adopt a socially situated entrepreneurial cognition approach to theorize how accelerator expertise, existing at a meso‐level, intermediates between (micro‐level) founders and the (macro‐level) ecosystem. In our model, four types of accelerator expertise—connection, development, coordination, and selection—together increase stakeholders’ commitment to the entrepreneurial ecosystem, leading to venture validation (success or failure) and ecosystem additionality. These findings indicate that accelerators contribute to ecosystems in a way that is distinct from, but supportive of, building individual ventures.Managerial Summary: Accelerators are a new form of entrepreneurial support organization. These organizations typically focus on developing individual start‐ups, but we find that they also help develop entrepreneurial ecosystems. They do so by acting as a bridge between start‐ups and the broader entrepreneurial environmental resources by: (a) helping form connections, (b) helping develop individual start‐ups, (c) helping coordinate the right match among the various players in the ecosystem, and (d) helping select mentors and founders with the appropriate motivation and knowledge. As these accelerators apply this expertise in this go‐between role, they help build commitment to the broader ecosystem. Furthermore, they enable success (or fast failure) of individual start‐ups and do so in a way that develops the overall entrepreneurial capacity of the broader entrepreneurial ecosystem.
Heterojunction‐Assisted Co3S4@Co3O4 Core–Shell Octahedrons for Supercapacitors and Both Oxygen and Carbon Dioxide Reduction Reactions
Authors: Yan Yibo , Li Kaixin , Chen Xiaoping , Yang Yanhui , Lee Jong‐Min 
Published: November 2017

AbstractExpedition of electron transfer efficiency and optimization of surface reactant adsorption products desorption processes are two main challenges for developing non‐noble catalysts in the oxygen reduction reaction (ORR) and CO2 reduction reaction (CRR). A heterojunction prototype on Co3S4@Co3O4 core–shell octahedron structure is established via hydrothermal lattice anion exchange protocol to implement the electroreduction of oxygen and carbon dioxide with high performance. The synergistic bifunctional catalyst consists of p‐type Co3O4 core and n‐type Co3S4 shell, which afford high surface electron density along with high capacitance without sacrificing mechanical robustness. A four electron ORR process, identical to the Pt catalyzed ORR, is validated using the core–shell octahedron catalyst. The synergistic interaction between cobalt sulfide and cobalt oxide bicatalyst reduces the activation energy to convert CO2 into adsorbed intermediates and hereby enables CRR to run at a low overpotential, with formate as the highly selective main product at a high faraday efficiency of 85.3%. The remarkable performance can be ascribed to the synergistic coupling effect of the structured co‐catalysts; heterojunction structure expedites the electron transfer efficiency and optimizes surface reactant adsorption product desorption processes, which also provide theoretical and pragmatic guideline for catalyst development and mechanism explorations.
Behaviour of double shear connections with injection bolts
Authors: Kolstein Henk , Li Jingbin , Koper Axel , Gard Wolfgang , Nijgh Martin , Veljkovic Milan 
Published: November 2017

AbstractThe RFCS project SIROCO (2014–17) included research on the further development and optimization of double shear connections with injection bolts to achieve slip‐ and creep‐resistant bolted connections considering various influencing parameters. The type of resin, the curing condition of the resin, the geometrical and mechanical characteristics of the connection and the type of loading were studied. Results showed, for example, that of the five epoxy resins investigated, only RenGel SW404 + HY2404 (Araldite) fulfils the requirements given in Eurocode 3. A bearing stress of 175 MPa is safely allowable in the long‐term without exceeding imposed deformation limits.