bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bullen's Parameter as a Seismic Observable for Spin Crossovers in the Lower Mantle
Authors: Valencia‐Cardona Juan J. , Williams Quentin , Shukla Gaurav , Wentzcovitch Renata M. 
Published: September 2017

AbstractElastic anomalies produced by the spin crossover in ferropericlase have been documented by both first‐principles calculations and high pressure‐temperature experiments. The predicted signature of this spin crossover in the lower mantle is, however, subtle and difficult to geophysically observe within the mantle. Indeed, global seismic anomalies associated with spin transitions have not yet been recognized in seismologic studies of the deep mantle. A sensitive seismic parameter is needed to determine the presence and amplitude of such a spin crossover signature. The effects of spin crossovers on Bullen's parameter, η, are assessed here for a range of compositions, thermal profiles, and lateral variations in temperature within the lower mantle. Velocity anomalies associated with the spin crossover in ferropericlase span a depth range near 1,000 km for typical mantle temperatures. Positive excursions of Bullen's parameter with a maximum amplitude of ∼0.03 are calculated to be present over a broad depth range within the middle‐to‐deep lower mantle: these are largest for peridotitic and harzburgitic compositions. These excursions are highest in amplitude for model lower mantles with large lateral thermal variations and with cold downwellings having longer lateral length‐scales relative to hot upwellings. We conclude that predicted deviations in Bullen's parameter due to the spin crossover in ferropericlase for geophysically relevant compositions may be sufficiently large to resolve in accurate seismic inversions of this parameter and could shed light on both the lateral variations in temperature at depth within the lower mantle, and the amount of ferropericlase at depth.
Multiple‐Satellite Observation of Magnetic Dip Event During the Substorm on 10 October 2013
Authors: He Zhaoguo , Chen Lunjin , Zhu Hui , Xia Zhiyang , Reeves G. D. , Xiong Ying , Xie Lun , Cao Yong 
Published: September 2017

AbstractWe present a multiple‐satellite observation of the magnetic dip event during the substorm on 10 October 2013. The observation illustrates the temporal and spatial evolution of the magnetic dip and gives a compelling evidence that ring current ions induce the magnetic dip by enhanced plasma beta. The dip moves with the energetic ions in a comparable drift velocity and affects the dynamics of relativistic electrons in the radiation belt. In addition, the magnetic dip provides a favorable condition for the electromagnetic ion cyclotron (EMIC) wave generation based on the linear theory analysis. The calculated proton diffusion coefficients show that the observed EMIC wave can lead to the pitch angle scattering losses of the ring current ions, which in turn partially relax the magnetic dip in the observations. This study enriches our understanding of magnetic dip evolution and demonstrates the important role of the magnetic dip for the coupling of radiation belt and ring current.
Significant Aerosol Influence on the Recent Decadal Decrease in Tropical Cyclone Activity Over the Western North Pacific
Authors: Takahashi Chiharu , Watanabe Masahiro , Mori Masato 
Published: September 2017

AbstractOver the past two decades, the number of tropical cyclones (TCs) has decreased markedly in the southeastern part of the western North Pacific (WNP) as a component of the interdecadal variation. This decrease has partially been explained by an internal low‐frequency variability of sea surface temperature (SST) in the Pacific, but influences of external forcing remain unclear. Here we show that past changes in sulfate aerosol emissions contributed approximately 60% of the observed decreasing trends in TC genesis frequency in the southeastern WNP for 1992–2011, using multiple simulations by a global climate model. This decrease was mainly attributed to the increased vertical wind shear and decreased low‐level vorticity, associated with a trans‐basin multidecadal SST change driven by aerosol forcing. The near‐future projection shows that the aerosol forcing still has some potential influence on decadal TC change, but the projected decreasing frequency is mainly due to increasing greenhouse gases forcing.
Joint Inversion of Surface Wave Dispersions and Receiver Functions with P Velocity Constraints: Application to Southeastern Tibet
Authors: Li Jiangtao , Song Xiaodong , Zhu Lupei , Deng Yangfan 
Published: September 2017

AbstractWe introduced a P velocity model into the traditional joint inversion of P receiver function (RF) and surface wave dispersions to reduce model ambiguity. The method was implemented using a global search‐based algorithm and a flexible parameterization of a sedimentary layer and spline‐based parameterization that can represent sharp discontinuities. We applied the method to a dense array in SE Tibet (longitude ~97.5°E to 107°E, latitude ~25.3°N). Extensive tests using synthetic and real data suggest that the method is suitable and robust for a variety of velocity structures and Moho discontinuities and can simultaneously provide the crustal Vp/Vs profile and better constrained Moho depth. The flexibility of the parameterization and the inclusion of the Vp constraint are crucial in the improved model recovery. Artifacts may be created without including the sedimentary layer. Even when it is less perfect, a reasonable Vp model is valuable in such a joint inversion. We showed that crustal multiples in RFs may bias the traditional H‐k results when the crust structure is complex and should be avoided in a joint inversion before appropriate corrections can be made. The results from the joint inversion show two low‐velocity zones (LVZs) reported previously and were identified as channels of crustal flow. A prominent isolated LVZ is observed in the mid‐lower crust under the Xiaojiang fault area, which correlates with anomalously high Vp/Vs ratios, indicating possible partial melting. However, the other LVZ is imaged to be in the brittle shallow upper crust without very high Vp/Vs ratios, which is likely associated with crustal fault zones rather than partial melting. We observe clear low‐velocity structures in the mantle beneath the two crustal LVZs, which also correlate with zones of low resistivity. The crust‐mantle correlation may suggest influence of mantle processes on crustal deformation.
Intracellular Pathways Involved in Bone Regeneration Triggered by Recombinant Silk–Silica Chimeras
Authors: Martín‐Moldes Zaira , Ebrahimi Davoud , Plowright Robyn , Dinjaski Nina , Perry Carole C. , Buehler Markus J. , Kaplan David L. 
Published: September 2017

AbstractBiomineralization at the organic–inorganic interface is critical to many biology material functions in vitro and in vivo. Recombinant silk–silica fusion peptides are organic–inorganic hybrid material systems that can be effectively used to study and control biologically mediated mineralization due to the genetic basis of sequence control. However, to date, the mechanisms by which these functionalized silk–silica proteins trigger the differentiation of human mesenchymal stem cells (hMSCs) to osteoblasts remain unknown. To address this challenge, silk–silica surfaces are analyzed for silica–hMSC receptor binding and activation, and the intracellular pathways involved in the induction of osteogenesis on these bioengineered biomaterials. The induction of gene expression of αVβ3 integrin, all three mitogen‐activated protein kinsases, as well as c‐Jun, runt‐related transcription factor 2, and osteoblast marker genes is demonstrated upon growth of the hMSCs on the silk–silica materials. This induction of key markers of osteogenesis correlates with the content of silica on the materials. Moreover, computational simulations are performed for silk/silica‐integrin binding which show activation of αVβ3 integrin in contact with silica. This integrated computational and experimental approach provides insight into interactions that regulate osteogenesis toward more efficient biomaterial designs.
Development of a Dual‐Modally Traceable Nanoplatform for Cancer Theranostics Using Natural Circulating Cell‐Derived Microparticles in Oral Cancer Patients
Authors: Yu Zi‐Li , Zhang Wei , Zhao Jing‐Ya , Zhong Wen‐Qun , Ren Jian‐Gang , Wu Min , Zhang Zhi‐Ling , Pang Dai‐Wen , Zhao Yi‐Fang , Chen Gang 
Published: September 2017

AbstractCell‐derived microparticles (MPs), which are biogenic nanosized membrane vesicles that convey bioactive molecules between cells, have exhibited great potential to serve as therapeutic platforms. However, so far, all the MPs used as theranostic vectors in previous studies have been produced in vitro from cell culture supernatants, which is still associated with several concerns regarding practical applications. In this study, circulating MPs (CMPs), which are freshly purified from the peripheral blood of oral squamous cell carcinoma (OSCC) patients, are directly and efficiently embedded with ultrasmall near‐infrared‐fluorescent magnetic quantum dots (Ag2Se@Mn QDs) via electroporation. By virtue of the superior photostability, favorable biocompatibility, and dual‐mode traceability of Ag2Se@Mn QD‐labeled CMPs in vivo, the tissue distribution and natural tumor‐targeting behavior of CMPs from OSCC patients are directly visualized in living mice for the first time. Moreover, by simultaneously embedding antitumor siRNA and Ag2Se@Mn QDs into CMPs derived from OSCC patients, a dual‐modally traceable and actively tumor‐targeted nanoplatform for cancer theranostics is developed. This study reports the first reliable conjugation‐free labeling strategy for in vivo dual‐mode tracking of CMPs harvested from the human body, and, more importantly, reports the development of traceable tumor‐targeted theranostic vectors based on naturally occurring CMPs from cancer patients.
From Ionogels to Biredox Ionic Liquids: Some Emerging Opportunities for Electrochemical Energy Storage and Conversion Devices
Authors: Vioux André , Coasne Benoit 
Published: September 2017

AbstractIonic liquids (ILs) continue to receive attention for applications in electrochemistry because of their unique properties as charge carriers (electrolytes) and redox shuttles (solar cells) and their ability to promote energy storage either electrostatically (supercapacitors) or chemically (secondary batteries). More specifically, the confinement of ILs in nanopores or the adsorption at surfaces, are considered a promising strategy for all solid‐state energy storage and conversion devices. Upon such immobilization, one benefits from the specific properties of ILs (large electrochemical window, relatively high ionic conductivity, task‐specific functionalities, etc.) combined with surface and confinement effects that can be tuned by playing with the porosity and chemical nature of the host. Here, some emerging applications of ILs in electrochemistry are first discussed: silica‐based ionogels as solid electrolytes and systems that involve carbon host substrates, as typical electrode materials in electrical double layer capacitors and lithium secondary batteries. Also, a non‐exhaustive, yet a comprehensive picture of the confinement and surface effects at play in such applications is presented. Then, the confinement of task‐specific ILs such as protonic ILs, IL lithium salts, and biredox ILs, is discussed, which paves the way for promising perspectives. Finally, some concluding remarks are reported and directions for future work are suggested.
Factors underlying observed injury rate differences between temporary workers and permanent peers
Authors: Foley Michael 
Published: September 2017

BackgroundTemporary workers face increased risk of injury as compared to permanent workers in similar occupations. This study explores the role played by several potential risk factors.MethodsInjured temporary and permanent workers, matched by industry, tenure and demographic characteristics, were interviewed to isolate the association of temporary employment with several injury risk factors.ResultsTemporary workers had higher workers’ compensation claims rates than their permanent worker‐peers. In interviews temporary workers a reported a lower frequency of exposure to hazards. However, they also reported being less likely to be equipped to cope with hazards by such countermeasures as experience screening, safety training and task control.ConclusionPolicies are needed to improve screening and training of temporary workers to assigned tasks, to discourage job‐switching, to improve temporary workers’ hazard awareness, to protect their right to report unsafe conditions. The responsibilities of agencies and host employers for ensuring the safety of their temporary workers need clarification in regulatory policy.
Alcohol improves cerebellar learning deficit in myoclonus–dystonia: A clinical and electrophysiological investigation
Authors: Weissbach Anne , Werner Elisa , Bally Julien F. , Tunc Sinem , Löns Sebastian , Timmann Dagmar , Zeuner Kirsten E. , Tadic Vera , Brüggemann Norbert , Lang Anthony , Klein Christine , Münchau Alexander , Bäumer Tobias 
Published: September 2017

ObjectiveTo characterize neurophysiological subcortical abnormalities in myoclonus–dystonia and their modulation by alcohol administration.MethodsCerebellar associative learning and basal ganglia–brainstem interaction were investigated in 17 myoclonus–dystonia patients with epsilon‐sarcoglycan (SGCE) gene mutation and 21 age‐ and sex‐matched healthy controls by means of classical eyeblink conditioning and blink reflex recovery cycle before and after alcohol intake resulting in a breath alcohol concentration of 0.08% (0.8g/l). The alcohol responsiveness of clinical symptoms was evaluated by 3 blinded raters with a standardized video protocol and clinical rating scales including the Unified Myoclonus Rating Scale and the Burke–Fahn–Marsden Dystonia Rating Scale.ResultsPatients showed a significantly reduced number of conditioned eyeblink responses before alcohol administration compared to controls. Whereas the conditioning response rate decreased under alcohol intake in controls, it increased in patients (analysis of variance: alcohol state × group, p = 0.004). Blink reflex recovery cycle before and after alcohol intake did not differ between groups. Myoclonus improved significantly after alcohol intake (p = 0.016). The severity of action myoclonus at baseline correlated negatively with the conditioning response in classical eyeblink conditioning in patients.InterpretationThe combination of findings of reduced baseline acquisition of conditioned eyeblink responses and normal blink reflex recovery cycle in patients who improved significantly with alcohol intake suggests a crucial role of cerebellar networks in the generation of symptoms in these patients. Ann Neurol 2017;82:543–553
Structuring of Surfaces with Gold Nanoparticles by Using Bessel‐Like Beams
Authors: Stankevičius Evaldas , Garliauskas Mantas , Gedvilas Mindaugas , Tarasenko Nikolai , Račiukaitis Gediminas 
Published: September 2017

AbstractHere, the structuring of surfaces with gold nanoparticles by using Bessel‐like beam array is demonstrated. The experimental results show that the fabricated microring structures containing gold nanoparticles have a surface plasmon resonance in the spectral range of 520–540 nm, which can be tuned by selecting the laser treatment parameters. Fabricated microring structures exhibit a lower light transmittance comparing with the randomly distributed gold nanoparticles for wavelengths 500–570 nm due to the growth in the size of nanoparticles. In the spectral range of 600–700 nm, the light transmittance through microring structures is higher compared with the randomly distributed gold nanoparticles because of the removal of gold nanoparticles as gold has high reflectivity for wavelengths longer than 600 nm. The demonstrated method enables an easy fabrication of microring structures having tunable plasmonic properties.
Black Pigment Gallstone Inspired Platinum‐Chelated Bilirubin Nanoparticles for Combined Photoacoustic Imaging and Photothermal Therapy of Cancers
Authors: Lee Dong Yun , Kim Jin Yong , Lee Yonghyun , Lee Soyoung , Miao Wenjun , Kim Hyeon Sik , Min Jung‐Joon , Jon Sangyong 
Published: September 2017

AbstractBilirubin (BR), a bile pigment that exerts potent antioxidant and anti‐inflammatory effects, is also a major constituent of black pigment gallstones found in bile ducts under certain pathological conditions. Inspired by the intrinsic metal‐chelating power of BR found in gallstones, herein we report a cisplatin‐chelated BR‐based nanoparticle (cisPt@BRNP) for use as a new photonic nanomedicine for combined photoacoustic imaging and photothermal therapy of cancers. The cisPt@BRNPs were prepared by simply mixing cisplatin with BRNPs, yielding ca. 150‐nm‐size NPs. Upon near‐IR laser irradiation at 808 nm, cisPt@BRNPs generated considerable heat and induced clear death of cancer cells in vitro. Following intravenous injection into human colon cancer‐bearing mice, cisPt@BRNPs allowed effective tumor visualization by photoacoustic imaging and remarkable antitumor efficacy by photothermal therapy, suggesting their potential for use as a new photonic nanomedicine for cancer therapy.
A Multiple‐Stimulus‐Responsive Biomimetic Assembly Based on a Polyisocyanopeptide and Conjugated Polymer
Authors: Meng Fanfan , Xing Chengfen , Yuan Hongbo , Fan Yibing , Chai Ran , Zhan Yong 
Published: September 2017

AbstractAn assembly was fabricated and was revealed to be a multiple‐stimulus‐responsive biomimetic hybrid polymer architecture. It was constructed by the hydrophobic interactions between a conjugated polyfluorene that contained 2,1,3‐benzothiadiazole units (PFBT) and a tri(ethylene glycol)‐functionalized polyisocyanopeptide (3OEG‐PIC). The introduction of PFBT to the polyisocyanopeptide (PIC) network allowed for the incorporation of responsiveness to multiple stimuli including temperature, CO2, carbonic anhydrase, and nonlinear mechanics, which mimics natural processes and interactions. Furthermore, the light‐harvesting and signal amplification characteristics of PFBT endowed the supramolecular assembly with the essential function of fluorescence monitoring for biological processes.
The Oxidation of Hydrophobic Aromatic Substrates by Using a Variant of the P450 Monooxygenase CYP101B1
Authors: Sarkar Md. Raihan , Lee Joel H. Z. , Bell Stephen G. 
Published: September 2017

AbstractThe cytochrome P450 monooxygenase CYP101B1, from a Novosphingobium bacterium is able to bind and oxidise aromatic substrates but at a lower activity and efficiency than norisoprenoids and monoterpenoid esters. Histidine 85 of CYP101B1 aligns with tyrosine 96 of CYP101A1, which, in the latter enzyme forms the only hydrophilic interaction with its substrate, camphor. The histidine residue of CYP101B1 was mutated to phenylalanine with the aim of improving the activity of the enzyme for hydrophobic substrates. The H85F mutant lowered the binding affinity and activity of the enzyme for β‐ionone and altered the oxidation selectivity. This variant also showed enhanced affinity and activity towards alkylbenzenes, styrenes and methylnaphthalenes. For example the rate of product formation for acenaphthene oxidation was improved sixfold to 245 nmol per nmol CYP per min. Certain disubstituted naphthalenes and substrates, such as phenylcyclohexane and biphenyls, were oxidised with lower activity by the H85F variant. Variants at H85 (A and G) designed to introduce additional space into the active site so as to accommodate these larger substrates did not improve the oxidation activity. As the H85F mutant of CYP101B1 improved the oxidation of hydrophobic substrates, this residue is likely to be in the substrate binding pocket or the access channel of the enzyme. The side chain of the histidine might interact with the carbonyl groups of the favoured norisoprenoid substrates of CYP101B1.
Facile Structure Tuning of a Methanol‐Synthesis Catalyst towards the Direct Synthesis of Dimethyl Ether from Syngas
Authors: Jeong Cheonwoo , Ham Hyungwon , Bae Jong Wook , Kang Dong‐Chang , Shin Chae‐Ho , Baik Joon Hyun , Suh Young‐Woong 
Published: September 2017

AbstractHeterogeneous catalysts of bifunctionality offer improved process efficiency and enhanced product yield in multistep chemical transformations conducted in a consecutive manner. However, this has seldom been realized in coprecipitated catalysts owing to the complexity of the synthesis. By adjusting the synthesis protocol of an industrial methanol‐synthesis catalyst as a model system, herein we demonstrate the bifunctional effect of Al2O3/Cu/ZnO catalysts to enable the direct production of dimethyl ether from synthesis gas with yields that are 2–3‐fold higher than those obtained with their conventional counterparts, with a greater number of accessible Cu surface atoms and more Al2O3 acid sites existing at the external particle surface. This is achieved by preparing the fully developed Cu,Zn precursor of a specific structure with surface‐decorated Al species. Our approach paves the way towards the rational design of multicomponent precipitated catalysts with tunable bifunctionality for practical cascade reactions.
Modulation of Nitrile Hydratase Regioselectivity towards Dinitriles by Tailoring the Substrate Binding Pocket Residues
Authors: Cheng Zhongyi , Cui Wenjing , Xia Yuanyuan , Peplowski Lukasz , Kobayashi Michihiko , Zhou Zhemin 
Published: September 2017

AbstractThe regioselective hydration of dinitriles is one of the most attractive approaches to prepare ω‐cyanocarboxamides or diamides and such regioselectivity is often beyond the capability of chemical catalysts. The use of nitrile hydratase to biotransform dinitriles selectively would be highly desirable. Molecular docking of two aliphatic dinitriles and two aromatic dinitriles into the active site of a nitrile hydratase (NHase) from Rhodococcus rhodochrous J1 allowed the identification of proximal NHase substrate binding pocket residues. Four residues (βLeu48, βPhe51, βTyr68, and βTrp72) were selected for single‐ and double‐point mutations to modulate the NHase regioselectivity towards dinitriles. Several NHase mutants with an altered regioselectivity were obtained, and the best one was Y68T/W72Y. Docking experiments further indicated that the poor binding affinity of aliphatic and aromatic ω‐cyanocarboxamides to the NHase variants resulted in distinct regioselectivity between wild‐type and mutated NHases.
Tungsten‐Based Bimetallic Catalysts for Selective Cleavage of Lignin C−O Bonds
Authors: Ji Jianwei , Guo Haiwei , Li Changzhi , Qi Zaojuan , Zhang Bo , Dai Tao , Jiang Min , Ren Chuanqing , Wang Aiqin , Zhang Tao 
Published: September 2017

AbstractTungsten‐based bimetallic catalysts M–W/AC (M=Ru, Pt, and Pd; AC=activated carbon) exhibited high activity and selectivity in the hydrogenolysis of typical α‐O‐4 model compounds and deconstruction of lignin feedstock for the production of aromatic chemicals. Synergy effect was observed between tungsten and noble‐metal species, which on the one hand modulated the hydrogenolysis activity of tungsten and improved the activity of catalyst, and on the other hand suppressed overhydrogenation that avoided the formation of cycloalkanes. The conversion of α‐O‐4 model compounds with different substituents showed that electronic effects play an important role in stabilizing the reaction intermediates, and the electron‐donating methoxy group on the aromatic ring accelerated the hydrogenolysis efficiency. Solvent effect was another factor that determined hydrogenolysis efficiency; dipolar aprotic solvents such as n‐hexane provided the high yields of target aromatics. In the conversion of realistic lignins, the bimetallic catalyst showed excellent activity not only in α‐O‐4 cleavage but also in the hydrogenolysis of other major linkages such as β‐O‐4 and β−β between aromatic units, so that a high yield of liquid oil was obtained from lignin.