bluuebunny/crossref_metadata_2025 huggingface dataset:
Protein phosphatase 2A and tau: an orchestrated ‘Pas de Deux’
Authors: Taleski Goce , Sontag Estelle
Published: November 2017

The neuronal microtubule‐associated protein tau serves a critical role in regulating axonal microtubule dynamics to support neuronal and synaptic functions. Furthermore, it contributes to glutamatergic regulation and synaptic plasticity. Emerging evidence also suggests that tau serves as a signaling scaffold. Tau function and subcellular localization are tightly regulated, in part, by the orchestrated interplay between phosphorylation and dephosphorylation events. Significantly, protein phosphatase type 2A (PP2A), encompassing the regulatory PPP2R2A (or Bα) subunit, is a major brain heterotrimeric enzyme and the primary tau Ser/Thr phosphatase in vivo. Herein, we closely examine how the intimate and compartmentalized interactions between PP2A and tau regulate tau phosphorylation and function, and play an essential role in neuronal homeostasis. We also review evidence supporting a strong link between deregulation of tau–PP2A functional interactions and the molecular underpinnings of various neurodegenerative diseases collectively called tauopathies. Lastly, we discuss the opportunities and associated challenges in more specifically targeting PP2A–tau interactions for drug development for tauopathies.
How to Define the Mean Square Amplitude of Solar Wind Fluctuations With Respect to the Local Mean Magnetic Field
Authors: Podesta John J.
Published: November 2017

Over the last decade it has become popular to analyze turbulent solar wind fluctuations with respect to a coordinate system aligned with the local mean magnetic field. This useful analysis technique has provided new information and new insights about the nature of solar wind fluctuations and provided some support for phenomenological theories of MHD turbulence based on the ideas of Goldreich and Sridhar. At the same time it has drawn criticism suggesting that the use of a scale‐dependent local mean field is somehow inconsistent or irreconcilable with traditional analysis techniques based on second‐order structure functions and power spectra that, for stationary time series, are defined with respect to the constant (scale‐independent) ensemble average magnetic field. Here it is shown that for fluctuations with power law spectra, such as those observed in solar wind turbulence, it is possible to define the local mean magnetic field in a special way such that the total mean square amplitude (trace amplitude) of turbulent fluctuations is approximately the same, scale by scale, as that obtained using traditional second‐order structure functions or power spectra. This fact should dispel criticism concerning the physical validity or practical usefulness of the local mean magnetic field in these applications.
Solar Illumination Control of the Polar Wind
Authors: Maes L. , Maggiolo R. , De Keyser J. , André M. , Eriksson A. I. , Haaland S. , Li K. , Poedts S.
Published: November 2017

Polar wind outflow is an important process through which the ionosphere supplies plasma to the magnetosphere. The main source of energy driving the polar wind is solar illumination of the ionosphere. As a result, many studies have found a relation between polar wind flux densities and solar EUV intensity, but less is known about their relation to the solar zenith angle at the ionospheric origin, certainly at higher altitudes. The low energy of the outflowing particles and spacecraft charging means it is very difficult to measure the polar wind at high altitudes. We take advantage of an alternative method that allows estimations of the polar wind flux densities far in the lobes. We analyze measurements made by the Cluster spacecraft at altitudes from 4 up to 20 RE. We observe a strong dependence on the solar zenith angle in the ion flux density and see that both the ion velocity and density exhibit a solar zenith angle dependence as well. We also find a seasonal variation of the flux density.
Properties of the Equatorial Magnetotail Flanks ∼50–200 RE Downtail
Authors: Artemyev A. V. , Angelopoulos V. , Runov A. , Wang C.‐P. , Zelenyi L. M.
Published: November 2017

In space, thin boundaries separating plasmas with different properties serve as a free energy source for various plasma instabilities and determine the global dynamics of large‐scale systems. In planetary magnetopauses and shock waves, classical examples of such boundaries, the magnetic field makes a significant contribution to the pressure balance and plasma dynamics. The configuration and properties of such boundaries have been well investigated and modeled. However, much less is known about boundaries that form between demagnetized plasmas where the magnetic field is not important for pressure balance. The most accessible example of such a plasma boundary is the equatorial boundary layer of the Earth's distant magnetotail. Rather, limited measurements since its first encounter in the late 1970s by the International Sun‐Earth Explorer‐3 spacecraft revealed the basic properties of this boundary, but its statistical properties and structure have not been studied to date. In this study, we use Geotail and Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) missions to investigate the equatorial boundary layer from lunar orbit (∼55 Earth radii, RE, downtail) to as far downtail as ∼200 RE. Although the magnetic field has almost no effect on the structure of the boundary layer, the layer separates well the hot, rarefied plasma sheet from dense cold magnetosheath plasmas. We suggest that the most important role in plasma separation is played by polarization electric fields, which modify the efficiency of magnetosheath ion penetration into the plasma sheet. We also show that the total energies (bulk flow plus thermal) of plasma sheet ions and magnetosheath ions are very similar; that is, magnetosheath ion thermalization (e.g., via ion scattering by magnetic field fluctuations) is sufficient to produce hot plasma sheet ions without any additional acceleration.
Monte Carlo Approach for Estimating Density and Atomic Number From Dual‐Energy Computed Tomography Images of Carbonate Rocks
Authors: Victor Rodolfo A. , Prodanović Maša , Torres‐Verdín Carlos
Published: November 2017

We develop a new Monte Carlo‐based inversion method for estimating electron density and effective atomic number from 3‐D dual‐energy computed tomography (CT) core scans. The method accounts for uncertainties in X‐ray attenuation coefficients resulting from the polychromatic nature of X‐ray beam sources of medical and industrial scanners, in addition to delivering uncertainty estimates of inversion products. Estimation of electron density and effective atomic number from CT core scans enables direct deterministic or statistical correlations with salient rock properties for improved petrophysical evaluation; this condition is specifically important in media such as vuggy carbonates where CT resolution better captures core heterogeneity that dominates fluid flow properties. Verification tests of the inversion method performed on a set of highly heterogeneous carbonate cores yield very good agreement with in situ borehole measurements of density and photoelectric factor.
Seasonality of Formic Acid (HCOOH) in London during the ClearfLo Campaign
Authors: Bannan Thomas J. , Murray Booth A. , Le Breton Michael , Bacak Asan , Muller Jennifer B. A. , Leather Kimberley E. , Khan M. Anwar H. , Lee James D. , Dunmore Rachel E. , Hopkins James R. , Fleming Zoë L. , Sheps Leonid , Taatjes Craig A. , Shallcross Dudley E. , Percival Carl J.
Published: November 2017

Following measurements in the winter of 2012, formic acid (HCOOH) and nitric acid (HNO3) were measured using a chemical ionization mass spectrometer (CIMS) during the Summer Clean Air for London (ClearfLo) campaign in London, 2012. Consequently, the seasonal dependence of formic acid sources could be better understood. A mean formic acid concentration of 1.3 ppb and a maximum of 12.7 ppb was measured which is significantly greater than that measured during the winter campaign (0.63 ppb and 6.7 ppb, respectively). Daily calibrations of formic acid during the summer campaign gave sensitivities of 1.2 ion counts s−1 parts per trillion (ppt) by volume−1 and a limit of detection of 34 ppt. During the summer campaign, there was no correlation between formic acid and anthropogenic emissions such as NOx and CO or peaks associated with the rush hour as was identified in the winter. Rather, peaks in formic acid were observed that correlated with solar irradiance. Analysis using a photochemical trajectory model has been conducted to determine the source of this formic acid. The contribution of formic acid formation through ozonolysis of alkenes is important but the secondary production from biogenic VOCs could be the most dominant source of formic acid at this measurement site during the summer.
A Case Study in Low Aerosol Number Concentrations Over the Eastern North Atlantic: Implications for Pristine Conditions in the Remote Marine Boundary Layer
Authors: Pennypacker Sam , Wood Robert
Published: November 2017

We present a case study (20 September to 13 October 2015) of synergistic, multi‐instrument observations of aerosols, clouds, and the marine boundary layer (MBL) at the Eastern North Atlantic (ENA) Atmospheric Radiation Measurement site centered on a period of exceptionally low (20–50 cm−3) surface accumulation mode (0.1–1 μm) aerosol particle number concentrations. We divide the case study into three regimes (high, clean, and ultraclean) based on daily median number concentrations and compare finer resolution (hourly or less) observations between these regimes. The analysis focuses on the possibility of using these ultraclean events to study pristine conditions in the remote MBL, as well as examining evidence for a recently proposed conceptual model for the large‐scale depletion of cloud condensation nuclei‐sized particles in postfrontal air masses. Relative to the high and clean regimes, the ultraclean regime tends to exhibit significantly fewer particles between 0.1 and 0.4 μm in diameter and a relatively increased prevalence of larger accumulation mode particles. In addition, supermicron particles tend to dominate total scattering in the ultraclean regime, and there is little evidence for absorbing aerosol. These observations are more in‐line with a heavily scavenged but natural marine aerosol population and minimal contribution from continental sources such as anthropogenic pollution, biomass burning, or dust. The air masses with the consistently lowest accumulation mode aerosol number concentrations are largely dominated by heavily drizzling clouds with high liquid water path cores, deep decoupled boundary layers, open cellular organization, and notable surface forcing of subcloud turbulence, even at night.
On the Origins of Mars' Exospheric Nonthermal Oxygen Component as Observed by MAVEN and Modeled by HELIOSARES
Authors: Leblanc F. , Chaufray J. Y. , Modolo R. , Leclercq L. , Curry S. , Luhmann J. , Lillis R. , Hara T. , McFadden J. , Halekas J. , Schneider N. , Deighan J. , Mahaffy P. R. , Benna M. , Johnson R. E. , Gonzalez‐Galindo F. , Forget F. , Lopez‐Valverde M. A. , Eparvier F. G. , Jakosky B.
Published: November 2017

The first measurements of the emission brightness of the oxygen atomic exosphere by Mars Atmosphere and Volatile EvolutioN (MAVEN) mission have clearly shown that it is composed of a thermal component produced by the extension of the upper atmosphere and of a nonthermal component. Modeling these measurements allows us to constrain the origins of the exospheric O and, as a consequence, to estimate Mars' present oxygen escape rate. We here propose an analysis of three periods of MAVEN observations based on a set of three coupled models: a hybrid magnetospheric model (LATmos HYbrid Simulation (LatHyS)), an Exospheric General Model (EGM), and the Global Martian Circulation model of the Laboratoire de Météorologie Dynamique (LMD‐GCM), which provide a description of Mars' environment from the surface up to the solar wind. The simulated magnetosphere by LatHyS is in good agreement with MAVEN Plasma and Field Package instruments data. The LMD‐GCM modeled upper atmospheric profiles for the main neutral and ion species are compared to Neutral Gas and Ion Mass Spectrometer/MAVEN data showing that the LMD‐GCM can provide a satisfactory global view of Mars' upper atmosphere. Finally, we were able to reconstruct the expected emission brightness intensity from the oxygen exosphere using EGM. The good agreement with the averaged measured profiles by Imaging Ultraviolet Spectrograph during these three periods suggests that Mars' exospheric nonthermal component can be fully explained by the reactions of dissociative recombination of the O2+ ion in Mars' ionosphere, limiting significantly our ability to extract information from MAVEN observations of the O exosphere on other nonthermal processes, such as sputtering.
The Vertical Dust Profile Over Gale Crater, Mars
Authors: Guzewich Scott D. , Newman C. E. , Smith M. D. , Moores J. E. , Smith C. L. , Moore C. , Richardson M. I. , Kass D. , Kleinböhl A. , Mischna M. , Martín‐Torres F. J. , Zorzano‐Mier M.‐P. , Battalio M.
Published: November 2017

We create a vertically coarse, but complete, profile of dust mixing ratio from the surface to the upper atmosphere over Gale Crater, Mars, using the frequent joint atmospheric observations of the orbiting Mars Climate Sounder (MCS) and the Mars Science Laboratory Curiosity rover. Using these data and an estimate of planetary boundary layer (PBL) depth from the MarsWRF general circulation model, we divide the vertical column into three regions. The first region is the Gale Crater PBL, the second is the MCS‐sampled region, and the third is between these first two. We solve for a well‐mixed dust mixing ratio within this third (middle) layer of atmosphere to complete the profile. We identify a unique seasonal cycle of dust within each atmospheric layer. Within the Gale PBL, dust mixing ratio maximizes near southern hemisphere summer solstice (Ls = 270°) and minimizes near winter solstice (Ls = 90–100°) with a smooth sinusoidal transition between them. However, the layer above Gale Crater and below the MCS‐sampled region more closely follows the global opacity cycle and has a maximum in opacity near Ls = 240° and exhibits a local minimum (associated with the “solsticial pause” in dust storm activity) near Ls = 270°. With knowledge of the complete vertical dust profile, we can also assess the frequency of high‐altitude dust layers over Gale. We determine that 36% of MCS profiles near Gale Crater contain an “absolute” high‐altitude dust layer wherein the dust mixing ratio is the maximum in the entire vertical column.
Mid‐Piacenzian Variability of Nordic Seas Surface Circulation Linked to Terrestrial Climatic Change in Norway
Authors: Panitz Sina , De Schepper Stijn , Salzmann Ulrich , Bachem Paul E. , Risebrobakken Bjørg , Clotten Caroline , Hocking Emma P.
Published: November 2017

During the mid‐Piacenzian, Nordic Seas sea surface temperatures (SSTs) were higher than today. While SSTs provide crucial climatic information, on their own they do not allow a reconstruction of potential underlying changes in water masses and currents. A new dinoflagellate cyst record for Ocean Drilling Program (ODP) Site 642 is presented to evaluate changes in northward heat transport via the Norwegian Atlantic Current (NwAC) between 3.320 and 3.137 Ma. The record is compared with vegetation and SST reconstructions from Site 642 and SSTs from Iceland Sea ODP Site 907 to identify links between SSTs, ocean currents, and vegetation changes. The dinocyst record shows that strong Atlantic water influence via the NwAC corresponds to higher‐than‐present SSTs and cool temperate vegetation during Marine Isotope Stage (MIS) transition M2–M1 and KM5. Reduced Atlantic water inflow relative to the warm stages coincides with near‐modern SSTs and boreal vegetation during MIS M2, KM6, and KM4–KM2. During most of the studied interval, a strong SST gradient between Sites 642 and 907 indicates the presence of a proto‐Arctic Front (AF). An absent gradient during the first half of MIS KM6, due to reduced Atlantic water influence at Site 642 and warm, presumably Atlantic water reaching Site 907, is indicative of a weakened NwAC and East Greenland Current. We conclude that repeated changes in Atlantic water influence directly affect terrestrial climate and that an active NwAC is needed for an AF to develop. Obliquity forcing may have played a role, but the correlation is not consistent.
The central domain of UNC‐45 chaperone inhibits the myosin power stroke
Authors: Bujalowski Paul J. , Nicholls Paul , Garza Eleno , Oberhauser Andres F.
Published: November 2017

The multidomain UNC‐45B chaperone is crucial for the proper folding and function of sarcomeric myosin. We recently found that UNC‐45B inhibits the translocation of actin by myosin. The main functions of the UCS and TPR domains are known but the role of the central domain remains obscure. Here, we show—using in vitro myosin motility and ATPase assays—that the central domain alone acts as an inhibitor of the myosin power stroke through a mechanism that allows ATP turnover. Hence, UNC‐45B is a unique chaperone in which the TPR domain recruits Hsp90; the UCS domain possesses chaperone‐like activities; and the central domain interacts with myosin and inhibits the actin translocation function of myosin. We hypothesize that the inhibitory function plays a critical role during the assembly of myofibrils under stress and during the sarcomere development process.
Respiratory Syncytial Virus
Authors: Melero José A , Trento Alfonsina , Mas Vicente
Published: November 2017

Human respiratory syncytial virus (hRSV) is the leading cause of acute lower respiratory infections in infants and young children worldwide. Epithelial cells lining the nasal passages and respiratory tract are the primary target of hRSV infection. Replication of hRSV in the host cell follows the general strategy of theMononegavirales. Cells respond to hRSV infection by producing a variety of cytokines, chemokines and interferons that are involved in the host inflammatory response. Although primary hRSV infection occurs at an early age, immunity is short‐lived or incomplete and reinfections occur throughout life. In fact, hRSV is also a pathogen of major importance for the elderly and immunocompromised adults. Initial efforts to develop a vaccine based on formalin‐inactivated virus resulted in vaccine‐enhanced disease after natural infection. However, recent advances on hRSV immunobiology have brought effective vaccines and antivirals as realistic objectives in a foreseeable future.

Key Concepts

Human respiratory syncytial virus (hRSV) is the leading cause of serious respiratory tract disease in children and infants worldwide but also a pathogen of recognised importance in the elderly and immunocompromised adults.

hRSV belongs to theOrthopneumovirusgenus of thePneumoviridaefamily within theMononegaviralesorder of negative‐strand RNA viruses.

The hRSV genome comprises 10 genes that encode 11 viral proteins.

hRSV derives its name from the formation of multinucleated, fused cells (syncytia), which are the hallmark of infection of cultured cells or lung tissue.

Following attachment to the target cell, entry by hRSV is mediated by fusion of the viral envelope with the host cell plasma membrane at neutral pH.

The entire replication cycle of hRSV takes place in the cytoplasm of the infected cell.

Reverse genetics has permitted the recovery of infectious hRSV from complementary DNA.

hRSV strains disseminate rapidly worldwide, accumulating mutations predominantly in the attachment protein.

Pathology associated with hRSV infections is not only the result of direct virus injury, but largely the consequence of an aberrant immune/inflammatory response.

Palivizumab, a neutralising monoclonal antibody directed against the hRSV fusion protein, is the only product available in the market for specific prophylactic treatment of children at high risk of severe infection.
Eye: Proteomics
Authors: Sharma Tasneem P , Clark Abbot F
Published: November 2017

Vision is our most precious sense, and numerous ocular diseases, such as age‐related macular degeneration, glaucoma and diabetic retinopathy, are responsible for visual impairment and blindness in hundreds of millions of individuals worldwide. In the past several years, a number of advances have been made to better understand ocular biology and diseases. Research in ocular proteomics of ocular tissues and cells, such as the trabecular meshwork, retina, optic nerve head, retinal pigment epithelium, cornea, lens, sclera, tears, aqueous humour and vitreous humour, has allowed the identification of eye proteins and protein modifications that are involved in ocular development, ageing and disease. Proteomics allows biologically relevant targeting of disease diagnosis, prognosis and drug‐response evaluations. This provides an important foundation for better understanding of ocular biology and disease pathogenesis.

Key Concepts

The eye is a unique sensory organ.

A wide variety of proteomics techniques are being used to identify proteins and protein modifications that are involved in ocular development, ageing and a wide variety of ocular diseases.

Eye proteomics can be very challenging due to the very limited quantity of ocular tissues and fluids available for analysis.

Posttranslational protein modifications are commonly associated with a variety of ocular diseases, such as glaucoma, macular degeneration and cataracts.

Serum proteomics is being used to examine systemic effects of specific ocular diseases.

Proteomics studies have been performed with ocular fluids such as tears, aqueous humour and vitreous humour.

Proteomics‐based technologies allow for the development of biological and clinical ocular therapeutics.

Biomarker identification allows for determining reasonable stages of disease progression.
Minimal mask immobilization with optical surface guidance for head and neck radiotherapy
Authors: Zhao Bo , Maquilan Genevieve , Jiang Steve , Schwartz David L.
Published: November 2017

Purpose

Full face and neck thermoplastic masks provide standard‐of‐care immobilization for patients receiving H&N IMRT. However, these masks are uncomfortable and increase skin dose. The purpose of this pilot trial was to investigate the feasibility and setup accuracy of minimal face and neck mask immobilization with optical surface guidance.

Methods

Twenty patients enrolled onto this IRB‐approved protocol. Patients were immobilized with masks securing only forehead and chin. Shoulder movement was restricted by either moldable cushion or hand held strap retractors. Positional information, including isocenter location and CT skin contours, were imported to a commercial surface image guidance system. Patients typically received standard‐of‐care IMRT to 60–70 Gy in 30–33 fractions. Patients were first set up to surface markings with optical image guidance referenced to regions of interest (ROIs) on simulation CT images. Positioning was confirmed by in‐room CBCT. Following six‐dimensional robotic couch correction, a new optical real‐time surface image was acquired to track intrafraction motion and to serve as a reference surface for setup at the next treatment fraction. Therapists manually recorded total treatment time as well as couch shifts based on kV imaging. Intrafractional ROI motion tracking was automatically recorded by the optical image guidance system. Patient comfort was assessed by self‐administered surveys.

Results

Setup error was measured as six‐dimensional shifts (vertical/longitudinal/lateral/rotation/pitch/roll). Mean error values were −0.51 ± 2.42 mm, −0.49 ± 3.30 mm, 0.23 ± 2.58 mm, −0.15 ± 1.01o, −0.02 ± 1.19o, and 0.06 ± 1.08o, respectively. Average treatment time was 21.6 ± 8.4 mins). Subjective comfort during surface‐guided treatment was confirmed on patient surveys.

Conclusion

These pilot results confirm feasibility of minimal mask immobilization combined with commercially available optical image guidance. Patient acceptance of minimal mask immobilization has been encouraging. Follow‐up validation, with direct comparison to standard mask immobilization, appears warranted.
3D Maskless Micropatterning for Regeneration of Highly Organized Tubular Tissues
Authors: Ma Chi , Qu Tiejun , Chang Bei , Jing Yan , Feng Jerry Q. , Liu Xiaohua
Published: November 2017

Micropatterning is a widely used powerful tool to create highly ordered microstructures on material surfaces. However, due to technical limitations, the integration of micropatterned microstructures into bioinspired 3D scaffolds to successfully regenerate well‐organized functional tissues is not achieved. In this work, a unique maskless micropatterning technology is reported to create 3D nanofibrous matrices with highly organized tubular architecture for tissue regeneration. This micropatterning method is a laser‐guided, noncontact, high‐precision, flexible computer programming of machining process that can create highly ordered tubules with the density ranged from 1000 to 60 000 mm−2 and the size varied from 300 nm to 30 µm in the bioinspired 3D matrix. The tubular architecture presents pivotal biophysical cues to control dental pulp stem cell alignment, migration, polarization, and differentiation. More importantly, when using this 3D tubular hierarchical matrix as a scaffold, this study successfully regenerates functional tubular dentin that has the same well‐organized microstructure as its natural counterpart. This 3D maskless micropattern approach represents a powerful avenue not only for the exploration of cell–material interactions in 3D, but also for the regeneration of functional tissues with well‐organized microstructures.
Placental Drug Transport‐on‐a‐Chip: A Microengineered In Vitro Model of Transporter‐Mediated Drug Efflux in the Human Placental Barrier
Authors: Blundell Cassidy , Yi Yoon‐Suk , Ma Lin , Tess Emily R. , Farrell Megan J. , Georgescu Andrei , Aleksunes Lauren M. , Huh Dongeun
Published: November 2017

The current lack of knowledge about the effect of maternally administered drugs on the developing fetus is a major public health concern worldwide. The first critical step toward predicting the safety of medications in pregnancy is to screen drug compounds for their ability to cross the placenta. However, this type of preclinical study has been hampered by the limited capacity of existing in vitro and ex vivo models to mimic physiological drug transport across the maternal–fetal interface in the human placenta. Here the proof‐of‐principle for utilizing a microengineered model of the human placental barrier to simulate and investigate drug transfer from the maternal to the fetal circulation is demonstrated. Using the gestational diabetes drug glyburide as a model compound, it is shown that the microphysiological system is capable of reconstituting efflux transporter‐mediated active transport function of the human placental barrier to limit fetal exposure to maternally administered drugs. The data provide evidence that the placenta‐on‐a‐chip may serve as a new screening platform to enable more accurate prediction of drug transport in the human placenta.
Nanostructured, Highly Anisotropic, and Mechanically Robust Polymer Electrolyte Membranes via Holographic Polymerization
Authors: Smith Derrick M. , Pan Qiwei , Cheng Shan , Wang Wenda , Bunning Timothy J. , Li Christopher Y.
Published: November 2017

Solid polymer electrolytes have shown to be a promising solution to suppressing dendrite growth for safer and higher performance lithium batteries. This article reports the fabrication and characterization of a series of nanostructured polymer electrolyte membranes (PEMs) comprised of poly(ethylene glycol)/bis(trifluoromethane)sulfonimide lithium electrolyte and acrylate–thiol‐ene crosslinked resin using a holographic polymerization (HP). Nanoscale long‐range order is observed and this unique structure imposes intriguing mechanical and ion‐conducting properties of the PEMs. The modulus of the holographically polymerized PEMs can be tuned to vary from 150 to 1300 MPa while room temperature conductivities of ≈2 × 10−5 S cm−1 and 90 °C conductivity of ≈5 × 10−4 S cm−1 are achieved. The HP nanostructure is also capable of directing ion transport either parallel or perpendicular to the membrane surface; an unprecedented ionic conductivity anisotropy as high as 3 × 105 is achieved. It is anticipated that these PEMs may be excellent candidates for lithium battery applications.
Electrooptical Synergy on Plasmon–Exciton‐Codriven Surface Reduction Reactions
Authors: Cao En , Guo Xiao , Zhang Liqiang , Shi Ying , Lin Weihua , Liu Xiaochun , Fang Yurui , Zhou Liyan , Sun Yinghui , Song Yuzhi , Liang Wenjie , Sun Mengtao
Published: November 2017

The monolayer graphene–Ag nanoparticles hybrid system is fabricated as the electrooptical‐coordinated controlled substrate for surface‐enhanced Raman scattering spectroscopy. Plasmon–exciton interactions in this hybrid system are systemically investigated and applied in the field of surface catalytic reactions, manipulated by the electrooptical synergy. Experimental results demonstrate that the surface catalytic reactions can not only be controlled by plasmon–exciton coupling, but also be affected by the gate voltages and electric currents (or bias voltages). The gate voltage can tune the density of state of electrons, and electric current can make the hot electrons near the Fermi level with higher kinetic energy. Both of gate voltages and electric currents can significantly promote the efficiency and probability of plasmon–exciton‐codriven surface catalytic reactions. The electrooptical device based on plasmon–exciton coupling can be potentially applied in the fields of sensor, catalysis, energy, and environment.
Controlled Selective CVD Growth of ZnO Nanowires Enabled by Mask‐Free Fabrication Approach using Aqueous Fe Catalytic Inks
Authors: Alameri Dheyaa , Ocola Leonidas E. , Kuljanshvili Irma
Published: November 2017

Fabrication process that enables selective growth of vertically oriented zinc oxide (ZnO) nanowires (NWs) via chemical vapor deposition method and mask‐free patterning approach is reported. It is shown that synthesis of high‐quality ZnO nanowires in various architectures is achievable by optimizing the growth conditions and by precise patterning of catalytic ink precursors. Parallel direct‐write patterning method is utilized to fabricate arrays of different architectures on Si/SiO2 substrates and directly on devices at preselected locations. The production of high‐quality, crystalline ZnO NWs is demonstrated using aqueous iron catalytic inks. The composition of the ink and the lateral size of the patterns deposited on substrates are shown to affect the resulting nanowires and thus, allowing to control the geometry (length and diameter) of the individual ZnO NWs in the patterned assemblies. The results indicate that our protocols are tailored to the fabrication of ZnO NWs with specific surface geometries and interface functionalities for variety of targeted device applications.
Precise Patterning of Large‐Scale TFT Arrays Based on Solution‐Processed Oxide Semiconductors: A Comparative Study of Additive and Subtractive Approaches
Authors: Li Minmin , Zheng Jiwen , Xu Huihua , Wang Zhaogui , Wu Qian , Huang Bolong , Zhou Hang , Liu Chuan
Published: November 2017

Precise patterning of solution‐processed oxide semiconductors is critical for cost‐effective, large‐scale, and high throughput fabrication of circuits and display application. In this paper, demonstration and comparison are made using the additive and subtractive patterning strategies to precisely fabricate wafer‐scale thin film transistor arrays (1600 devices), which are based on high‐quality solution‐processed indium zinc oxide (IZO) and indium gallium zinc oxide (IGZO). The IZO and IGZO TFTs exhibit field‐effect mobility up to 8.0 and 5.2 cm2 V−1 s−1 when using the additive method, whereas the highest mobility of 24.2 and 13.7 cm2 V−1 s−1 for IZO and IGZO TFTs is achieved when using the subtractive method. The X‐ray photoelectronic spectroscopy studies and quantitative 2D device simulations together reveal that good device performance is attributed to moderate shallow donor‐like states (providing electrons) from oxygen vacancy and few accepter‐like states (trapping electrons) resulted from the dense structural framework of MO bonds. After examining the uniformity and reliability of the devices, the solution‐patterned inverters are demonstrated using negative‐channel metal oxide semiconductors, which show full swing output transfer characteristics and thus provide a promising method for solution‐based fabrications of circuits.
Benzyne‐Promoted Curtius‐Type Rearrangement of Acyl Hydrazides in the Presence of Nucleophiles
Authors: Guo Jing‐Yu , Zhong Chen‐Hao , He Zeng‐Yang , Tian Shi‐Kai
Published: November 2017

A protocol has been developed for the Curtius‐type rearrangement of acyl hydrazides in the presence of nucleophiles by activating acyl hydrazides with benzyne to generate aminimide intermediates. A wide variety of N′‐methyl‐N′‐phenyl acyl hydrazides were treated with various alcohols in the presence of 2‐(trimethylsilyl)phenyl triflate and CsF under mild conditions to afford structurally diverse carbamates in moderate to excellent yields. Importantly, complete retention of configuration was observed in the reaction of enantioenriched α‐chiral alkanoyl hydrazides. Replacing the alcohol with water, an amine, an N′‐unsubstituted acyl hydrazide, an alkoxyamine, or a thiophenol in the reaction permitted facile synthesis of ureas and analogues.
A Three‐Component Enantioselective Cyclization Reaction Catalyzed by an Unnatural Amino Acid Derivative
Authors: de Gracia Retamosa María , Ruiz‐Olalla Andrea , Bello Tamara , de Cózar Abel , Cossío Fernando P.
Published: November 2017

A new diastereo‐ and enantioselective three‐component cyclization reaction is described. The reaction takes place between a ketone, a carboxylic acid, and a nitroalkene to yield a bicyclic octahydro‐2H‐indol‐2‐one scaffold possessing three chiral centers. This reaction involves a rearrangement of the nitro group under simple thermal conditions. A plausible mechanism is proposed for this new reaction based on DFT calculations and isotope‐labeling experiments. A new concise enantioselective synthesis of the alkaloid (+)‐pancracine is presented as an example of the potential of this novel organocatalytic cyclization reaction in the synthesis of natural products.
Thermally Activated Delayed Fluorescence in a Y3N@C80Endohedral Fullerene: Time‐Resolved Luminescence and EPR Studies
Authors: Zalibera Michal , Krylov Denis S. , Karagiannis Dimitrios , Will Paul‐Anton , Ziegs Frank , Schiemenz Sandra , Lubitz Wolfgang , Reineke Sebastian , Savitsky Anton , Popov Alexey A.
Published: November 2017

The endohedral fullerene Y3N@C80exhibits luminescence with reasonable quantum yield and extraordinary long lifetime. By variable‐temperature steady‐state and time‐resolved luminescence spectroscopy, it is demonstrated that above 60 K the Y3N@C80exhibits thermally activated delayed fluorescence with maximum emission at 120 K and a negligible prompt fluorescence. Below 60 K, a phosphorescence with a lifetime of 192±1 ms is observed. Spin distribution and dynamics in the triplet excited state is investigated with X‐ and W‐band EPR and ENDOR spectroscopies and DFT computations. Finally, electroluminescence of the Y3N@C80/PFO film is demonstrated opening the possibility for red‐emitting fullerene‐based organic light‐emitting diodes (OLEDs).
Statische und dynamische Probebelastungen an Stahlrohrpfählen in 40 m Wassertiefe in der Ostsee
Authors: Geduhn Magnus , Moreira Barbosa Pedro , Steenfelt Jørgen S. , Hust Augustesen Anders
Published: November 2017

Iberdrola baut derzeit den 350‐MW‐Offshore‐Windpark Wikinger in der deutschen Ostsee. Der Baugrund wird im Wesentlichen durch Geschiebemergel und Kreide dominiert. Ramboll IMS (vormals IMS Ingenieurgesellschaft mbH) war zusammen mit COWI als Joint‐Venture‐Partner verantwortlich für die Planung der tiefgegründeten Jacket‐Strukturen. Ramboll IMS hat auch die Rolle des geotechnischen Sachverständigen im Sinne der BSH‐Richtlinien für dieses Projekt übernommen und zudem zusammen mit COWI die Planung, Überwachung und Auswertung der hier vorgestellten Offshore‐Pfahlversuche durchgeführt. Die bislang veröffentlichten Pfahlbemessungsmethoden offenbaren signifikante Unsicherheiten für offene Stahlrohrpfähle in Kreide, die bei Anwendung zu bis zu 70 m langen Gründungspfählen führen würden. Um diesen Unsicherheiten zu begegnen, wurden im Auftrag des Projektentwicklers dynamische und vollständig autonome statische Offshore‐Pfahlprobebelastungen (Zugversuche) vor Beginn der Ausführungsplanung zur Gründung geplant, beauftragt und realisiert, um speziell die Mantelreibung in der Kreide nach verschiedenen Zeitpunkten nach Herstellung der Pfähle zu verifizieren und in die Ausführungsplanung einfließen zu lassen, um die Pfähle deutlich zu verkürzen. Die statischen Zugversuche und begleitenden dynamischen Pfahlprobebelastungen wurden zehn Wochen nach der jeweiligen Pfahlrammung an drei unterschiedlichen Standorten im Projektgebiet an Testpfählen mit 50 % reduziertem Außendurchmesser (D = 1,37 m) in etwa 40 m Wassertiefe durchgeführt. Dieser Beitrag gibt einen technischen Überblick über die durchgeführten Versuche und zeigt Risiken und Vorteile auf, die die Feldversuche rechtfertigen. Die auf Grundlage der Pfahlversuche gebaute mittlere Pfahllänge betrug 30 m. Einige gewonnene Erkenntnisse werden geteilt und Schlussfolgerungen hinsichtlich der Machbarkeit, der Gestaltung und der Planung von Offshore‐Pfahlprobebelastungen gezogen, die bislang einzigartig in der Umsetzung sind. Weitergehende Details zu den Versuchsergebnissen werden in einem Folgeaufsatz zusammengeführt und sollen 2018 veröffentlicht werden, da der Projektentwickler sich derzeit noch im direkten Wettbewerb um weitere Windparks in der Ostsee befindet.
Bauwerksmessungen versus Rechenkonzepte zur Beurteilung von Spannstahlermüdung in Betonbrücken
Authors: Sanio David , Löschmann Jens , Mark Peter , Ahrens Mark Alexander
Published: November 2017

Viele Bestandsbrücken sind hinsichtlich ihrer Tragfähigkeit und Gebrauchstauglichkeit neu zu bewerten. Seinerzeit nicht für die heutigen Anforderungen bemessen, nutzen etwa die verfeinerten Rechenansätze der Stufe 2 der Nachrechnungsrichtlinie Traglastreserven aus. Allerdings werden dabei auch rechnerische Defizite festgestellt, die nicht den optischen Zustand des Bauwerks widerspiegeln. In diesen Fällen können Messungen (Monitoring) zusätzliche Tragreserven identifizieren und so die Restnutzungsdauer wesentlich verlängern. Insbesondere die Ermüdung von Spann‐ und Betonstahl sowie die Gebrauchstauglichkeitsnachweise hängen wesentlich vom realen Tragverhalten ab und können durch ein zielgerichtetes Monitoring genauer bewertet werden. Dieses Vorgehen entspricht der – nur selten angewendeten – Stufe 3 der Nachrechnungsrichtlinie, die Messungen explizit erlaubt.

Der Beitrag identifiziert maßgebende Berechnungsgrößen des Ermüdungsnachweises und bewertet deren Einfluss. Die Vielzahl möglicher Messverfahren unterscheidet sich nach Aufwand und möglichem Erkenntnisgewinn. Zur Abwägung von Aufwand und Nutzen dient eine tabellierte Zusammenstellung als Entscheidungshilfe für den bearbeitenden Ingenieur. Sie unterstützt die Auswahl geeigneter Messverfahren und kann als Ausgangspunkt wirtschaftlicher, messwertgestützter Zustandsbewertungen des Tragwerks genutzt werden.

Mit der zielgerichteten Messung ist eine erhebliche Genauigkeitssteigerung möglich und damit verbunden eine Verlängerung der Nutzungsdauer. Mit verschiedenen Monitoringverfahren ließ sich etwa die Nutzungsdauer eines Referenzbauwerks um etwa ein 14‐Faches verlängern. Dies wird an Beispielen gezeigt.
Toward a harmonization of national sustainability requirements and criteria for solid biomass
Authors: Mai‐Moulin Thuy , Armstrong Simon , van Dam Jinke , Junginger Martin
Published: November 2017

This paper compares national sustainability support schemes and sustainability requirements in four countries that import solid biomass for heat and power generation: Belgium, Denmark, the UK, and the Netherlands. The paper also reviews voluntary certification schemes for solid biomass that may be used to demonstrate sustainability compliance. In the absence of mandatory EU criteria for solid biomass, different national support schemes and sustainability requirements may present barriers to trade. This paper identifies some possibilities for harmonization and provides suggestions for policymakers for the improvement and alignment of national sustainability requirements. Ultimately the paper suggests establishing a harmonized certification scheme in the short term based on legislative requirements in the four countries and in voluntary initiatives. The proposed harmonized certification scheme may also reduce both implementation costs and complexity for biomass suppliers and generators. In the long term, the paper recommends binding criteria on sustainability requirements for solid biomass at EU level. © 2017 The Authors. Biofuels, Bioproducts and Biorefining published by Society of Chemical Industry and John Wiley & Sons, Ltd
Effects of EMF emissions from undersea electric cables on coral reef fish
Authors: Kilfoyle Audie K. , Jermain Robert F. , Dhanak Manhar R. , Huston Joseph P. , Spieler Richard E.
Published: November 2017

The objective of this study was to determine if electromagnetic field (EMF) emissions from undersea power cables impacted local marine life, with an emphasis on coral reef fish. The work was done at the South Florida Ocean Measurement Facility of Naval Surface Warfare Center in Broward County, Florida, which has a range of active undersea detection and data transmission cables. EMF emissions from a selected cable were created during non‐destructive visual fish surveys on SCUBA. During surveys, the transmission of either alternating current (AC), direct current (DC), or none (OFF) was randomly initiated by the facility at a specified time. Visual surveys were conducted using standardized transect and point‐count methods to acquire reef fish abundances and species richness prior to and immediately after a change in transmission frequency. The divers were also tasked to note the reaction of the reef fish to the immediate change in EMF during a power transition. In general, analysis of the data did not find statistical differences among power states and any variables. However, this may be a Type II error as there are strong indications of a potential difference of a higher abundance of reef fish at the sites when the power was off, and further study is warranted. Bioelectromagnetics. 39:35–52, 2018. © 2017 Wiley Periodicals, Inc.
Change in bowel habit, abdominal pain, and a palpable abdominal mass in a 58‐year‐old female
Authors: Peacock Julian , Perkins Zane
Published: November 2017

Key Clinical Message

Giant colonic diverticulum is a rare complication of diverticulosis, which may present in the acute or chronic setting. Colonic resection and en bloc resection of the diverticulum are the favored management, however, conservative treatment remains an option that could be considered in asymptomatic patients with minimal symptoms.
Hierarchical Porous Nitrogen‐Doped Carbon Constructed of Crumpled and Interconnected Graphene‐Like Nanosheets for Sodium‐Ion Batteries and All‐Solid‐State Symmetric Supercapacitors
Authors: Jia Zhengbao , Chen Can , Xu Guobao , Wei Xiaolin , Yang Liwen
Published: November 2017

Hierarchical porous N‐doped carbon constructed of interconnected and crumpled graphene‐like nanosheets (designated as HGOCN‐A) is prepared by combining NaCl templating with KOH activation through the solid‐state pyrolysis of a urea and glucose complex. The self‐assembled soluble NaCl/KOH crystals serve as an in situ template and support for the production of carbon nanosheets with 3D hierarchical porous structure, and chemical activation from KOH benefits the formation of abundant mesopores between 2 and 50 nm in size. Owing to the synergistic effect associated with the 2D morphology, the high BET surface area, enriched nitrogen doping, as well as a more appropriate pore‐size distribution, the HGOCN‐A demonstrates excellent electrochemical behaviors as electrode materials for sodium‐ion batteries (SIBs) and all‐solid‐state symmetric supercapacitors. For SIBs, the HGOCN‐A anode exhibits a high capacity of 195 mAh g−1 at 0.1 A g−1 after 200 cycles, a long cycling stability with a capacity of 164 mAh g−1 after 400 cycles at 0.5 A g−1, and an excellent rate performance with a capacity of 108 mAh g−1 at 10 A g−1. For all‐solid‐state symmetric supercapacitors, the fabricated device possesses a superior capacitive property of 212 F g−1 at 0.5 A g−1, a high capacitance retention with 142 F g−1 at 10 A g−1, and outstanding cycling stability with 98 % capacitance retention after 2000 cycles at 1 A g−1. HGOCN‐A has great potential in future applications for high‐performance electrochemical energy storage devices.
Application of independent component analysis with semi‐supervised Laplacian regularization kernel density estimation
Authors: Fan Song , Zhang Yingwei
Published: November 2017

In this study, fault detection and fault reconstruction methods are developed using matrix factorization of component vectors obtained with independent component analysis (ICA). Two monitoring statistics are used for fault detection in a detailed analysis of the ICA data model. A fault reconstruction technique is proposed that can determine the normal value and an estimate of the fault magnitude from the measurements. A semi‐supervised Laplacian regularization (SLR) kernel density estimation approach is introduced to determine the normal operating region, which can significantly reduce the false alarm rate. These methods are applied to a hot galvanizing pickling waste liquor treatment process (HGPWLTP) to evaluate the performance of the proposed approach. The test results show that the proposed approach has satisfactory performance.
Model based multivariable control scheme in a reset configuration for stable multivariable systems
Authors: Pathiran Arun R. , Jagadeesan Prakash
Published: November 2017

The multivariable control scheme is a widely used advanced process control methodology to control key process variables in chemical engineering processes. However, successful implementation of multivariable control requires a simplified control structure, a lower number of tuning parameters, and an appropriate tuning method. In this work, a model based multivariable control scheme is realized in reset configuration for the control of stable multi‐input and multi‐output systems. This control scheme utilizes the process transfer function matrix and the inverse of the steady state gain matrix for its implementation. The control scheme has a single tuning parameter and also inherently takes into account the interaction that exists between process inputs and outputs. This scheme is easy to implement and apply in multivariable systems with multiple delays, high‐dimensional systems, non‐square systems, and systems with RHP zeros. Simulation examples from process system engineering such as industrial scale polymerization reactor system, quadruple‐tank system, temperature control for the four room process, and shell control problem are presented to show the efficacy of the proposed multivariable control scheme.