bluuebunny/crossref_metadata_2025 huggingface dataset:
X paragraphes sur les relais culturels de la représentation-monde
Authors: Masó Joana
Published: July 2015

En abordant le problème de la représentation chez les écrivains, penseurs et artistes français du xxe siècle, cet article cherche à prendre ses distances à l’égard des lectures qui ont pensé l’ekphrasis dans les études interartistiques en termes d’impérialisme du langage et de colonisation linguistique. On étudie dans cet essai différentes scènes consacrées à la peinture et à l’image dans À la recherche du temps perdu de Marcel Proust et La carte postale de Jacques Derrida afin d’y explorer ce que Derrida a pensé comme l’hyper-responsabilité de l’écrivain dans le monde de représentations et la culture dont nous héritons.
Gloss (à partir de quelques photos d’Ann Hamilton)
Authors: Armstrong Philip , Popovici-Toma Cosmin
Published: July 2015

À travers une lecture attentive de la série Face to Face d’Ann Hamilton – des photographies prises en exposant une pellicule photosensible posée dans la bouche de l’artiste – et suivant la réflexion de Jean-Luc Nancy sur la bouche dans Ego sum, ce texte traite de la relation entre « la matière photographique » et la question de l’ekphrasis. En prêtant attention aux manières dont la photographie vient au jour à travers les conditions de son énonciation, Face to Face déplace l’agencement temporel traditionnel de l’ekphrasis, où la représentation verbale tente de saisir la représentation visuelle. Ces photographies font plutôt passer au premier plan les conditions performatives de l’écriture ekphrastique, en déplaçant l’accent mis sur la description vers des questions d’exposition, de glossolalie et de parole.
On the symmetry of ionospheric polar cap patch exits around magnetic midnight
Authors: Moen J. , Hosokawa K. , Gulbrandsen N. , Clausen L. B. N.
Published: July 2015

In this paper we examine how polar cap patches, which have been frozen into the antisolar flow over the polar cap, are transported into the nighttime auroral oval. First we present a detailed case study from 12 January 2002, with continuous observations of polar cap patches exiting into the nighttime auroral oval in the Scandinavian sector. Satellite images of the auroral oval and all‐sky camera observations of 630.0 nm airglow patches are superimposed onto Super Dual Auroral Radar Network convection maps. These composite plots reveal that polar cap patches exit on both the dusk and on the dawn convection cells. Then we present statistics based on 8 years of data from the meridian scanning photometer at Ny‐Aalesund, Svalbard, to investigate the possible interplanetary magnetic field (IMF) By influence on the distribution of patch exits around magnetic midnight. The magnetic local time distribution of patch exits is almost symmetric around magnetic midnight, independent of IMF By polarity. Synthesizing these observations with previous results, we propose a three‐step mechanism for why patch material exits symmetrically around midnight. First, intake of patch material occurs on both convection cells for both IMF By polarities. Second, plasma intake by transient magnetopause reconnection stretches the newly cut polar cap patches into dawn‐dusk elongated forms during their transport into the polar cap. And finally at exit, dawn‐dusk elongated patches are split and diverted toward both the dawn and dusk flanks when grabbed by transient tail reconnection.
Reintroducing radiometric surface temperature into the Penman‐Monteith formulation
Authors: Mallick Kaniska , Boegh Eva , Trebs Ivonne , Alfieri Joseph G. , Kustas William P. , Prueger John H. , Niyogi Dev , Das Narendra , Drewry Darren T. , Hoffmann Lucien , Jarvis Andrew J.
Published: July 2015

Here we demonstrate a novel method to physically integrate radiometric surface temperature (TR) into the Penman‐Monteith (PM) formulation for estimating the terrestrial sensible and latent heat fluxes (H and λE) in the framework of a modified Surface Temperature Initiated Closure (STIC). It combines TR data with standard energy balance closure models for deriving a hybrid scheme that does not require parameterization of the surface (or stomatal) and aerodynamic conductances (gS and gB). STIC is formed by the simultaneous solution of four state equations and it uses TR as an additional data source for retrieving the “near surface” moisture availability (M) and the Priestley‐Taylor coefficient (α). The performance of STIC is tested using high‐temporal resolution TR observations collected from different international surface energy flux experiments in conjunction with corresponding net radiation (RN), ground heat flux (G), air temperature (TA), and relative humidity (RH) measurements. A comparison of the STIC outputs with the eddy covariance measurements of λE and H revealed RMSDs of 7–16% and 40–74% in half‐hourly λE and H estimates. These statistics were 5–13% and 10–44% in daily λE and H. The errors and uncertainties in both surface fluxes are comparable to the models that typically use land surface parameterizations for determining the unobserved components (gS and gB) of the surface energy balance models. However, the scheme is simpler, has the capabilities for generating spatially explicit surface energy fluxes and independent of submodels for boundary layer developments.
Zeta potential in intact natural sandstones at elevated temperatures
Authors: Vinogradov Jan , Jackson Matthew D.
Published: July 2015

We report measurements of the zeta potential of natural sandstones saturated with NaCl electrolytes of varying ionic strengths at temperatures up to 150°C. The zeta potential is always negative but decreases in magnitude with increasing temperature at low ionic strength (0.01 M) and is independent of temperature at high ionic strength (0.5 M). The pH also decreases with increasing temperature at low ionic strength but remains constant at high ionic strength. The temperature dependence of the zeta potential can be explained by the temperature dependence of the pH. Our findings are consistent with published models of the zeta potential, so long as the temperature dependence of the pH at low ionic strength is accounted for and can explain the hitherto contradictory results reported in previous studies.
The recent hiatus in global warming of the land surface: Scale‐dependent breakpoint occurrences in space and time
Authors: Ying Lingxiao , Shen Zehao , Piao Shilong
Published: July 2015

The spatial and temporal variability of the recent land warming hiatus have seldom been explored, despite their importance for understanding the mechanisms underlying the phenomenon. In this study, we applied piecewise linear regression to investigate the spatiotemporal patterns of the breakpoint time of warming over 40 years (1974–2013). Our results showed that at the global scale, mean annual temperature (MAT) over the land increased significantly until 2005 and that the warming trend then stalled. However, the breakpoint time of the warming varied greatly among different seasons and continents. We found no statistically significant breakpoint in MAT over the Northern Hemisphere, but MAT over the Southern Hemisphere showed a significant breakpoint (P < 0.001) in 1979. At the seasonal scale, only the winter season (December‐January‐February) showed a statistically significant breakpoint in global land temperature. The other seasons showed continuous increasing temperature during the whole study period. Our study examined the recent global warming hiatus on the land surface using an area‐weighted summary of a scale‐dependent phenomenon with substantial spatiotemporal heterogeneity and revealed the winter cooling in the Northern Hemisphere low‐middle latitudes in 1999–2008 as the major contributor to the global warming hiatus on land surface in 2005. This result highlights the importance of using a statistical method to identify the timing of climate phase change. A better understanding of the processes behind the spatiotemporal patterns of local‐scale breakpoint occurrences in land surface temperature would shed new light on the mechanisms of the recent global warming hiatus.
Response of the topside and bottomside ionosphere at low and middle latitudes to the October 2003 superstorms
Authors: Lei Jiuhou , Zhu Qingyu , Wang Wenbin , Burns Alan G. , Zhao Biqiang , Luan Xiaoli , Zhong Jiahao , Dou Xiankang
Published: July 2015

Ionospheric observations from the ground‐based GPS receiver network, CHAMP and GRACE satellites and ionosondes were used to examine topside and bottomside ionospheric variations at low and middle latitudes over the Pacific and American sectors during the October 2003 superstorms. The latitudinal variation and the storm time response of the ground‐based GPS total electron content (TEC) were generally consistent with those of the CHAMP and GRACE up‐looking TEC. The TECs at heights below the satellite altitudes during the main phases were comparable to, or even less than, the quiet time values. However, the storm time CHAMP and GRACE up‐looking TECs showed profound increases at low and middle latitudes. The ground‐based TEC and ionosonde data were also combined to study the TEC variations below and above the F2 peak height (hmF2). The topside TECs above hmF2 at low and middle latitudes showed significant increases during storm time; however, the bottomside TEC below hmF2 did not show so obvious changes. Consequently, the bottomside ionosphere made only a minor contribution to the ionospheric positive phase seen in the total TEC at low and middle latitudes. Moreover, at middle latitudes F2 peak electron densities during storm time did not have the obvious enhancements that were seen in both the ground‐based and topside TECs, although they were accompanied by increases of hmF2. Therefore, storm time TEC changes are not necessarily related to changes in ionospheric peak densities. Our results suggest that TEC increases at low and middle latitudes are also associated with effective plasma scale height variations during storms.
The seasonal cycle and variability of sea level in the South China Sea
Authors: Amiruddin A. M. , Haigh I. D. , Tsimplis M. N. , Calafat F. M. , Dangendorf S.
Published: July 2015

The spatial and temporal characteristics of the seasonal sea level cycle in the South China Sea (SCS) and its forcing mechanisms are investigated using tide gauge records and satellite altimetry observations along with steric and meteorological data. The coastal mean annual amplitude of the seasonal cycle varies between zero and 24 cm, reaching a maximum between July and January. The maximum mean semiannual amplitude is 7 cm, peaking between March and June. Along the coast, the seasonal cycle accounts for up to 92% of the mean monthly sea level variability. Atmospheric pressure explains a significant portion of the seasonal cycle with dominant annual signals in the northern SCS, the Gulf of Thailand and the north‐western Philippines Sea. The wind forcing is dominant on the shelf areas of the SCS and the Gulf of Thailand where a simple barotropic model forced by the local wind shows annual amplitudes of up to 27 cm. In the deep basin of the SCS, the Philippines Sea and the shallow Malacca Strait, the steric component is the major contributor with the maximum annual amplitudes reaching 15 cm. Significant variability in the seasonal cycle is found on a year‐to‐year basis. The annual and semiannual amplitudes vary by up to 63% and 45% of the maximum values, 15 cm and 11 cm, respectively. On average, stepwise regression analysis of contribution of different forcing factors accounts for 66% of the temporal variability of the annual cycle. The zonal wind was found to exert considerable influence in the Malacca Strait.
Dissimilatory nitrate reduction processes and associated contribution to nitrogen removal in sediments of the Yangtze Estuary
Authors: Deng Fengyu , Hou Lijun , Liu Min , Zheng Yanling , Yin Guoyu , Li Xiaofei , Lin Xianbiao , Chen Fei , Gao Juan , Jiang Xiaofen
Published: July 2015

Dissimilatory nitrate reduction processes, including denitrification, anaerobic ammonium oxidation (ANAMMOX), and dissimilatory nitrate reduction to ammonium (DNRA), play an important role in controlling the nitrate dynamics and fate in estuarine and coastal environments. We investigated potential rates of denitrification, ANAMMOX, and DNRA in the sediments of the Yangtze Estuary via slurry incubation experiments combined with isotope‐tracing techniques to reveal their respective contributions to total nitrate reduction in this hypereutrophic estuarine ecosystem. Measured rates of denitrification, ANAMMOX, and DNRA ranged from 0.06 to 4.51 µmol N kg−1 h−1, 0.01 to 0.52 µmol N kg−1 h−1, and 0.03 to 0.89 µmol N kg−1 h−1, respectively. These potential dissimilatory nitrate reduction process rates correlated significantly with salinity, sulfide, organic carbon, and nitrogen. Denitrification contributed 38–96% total nitrate reduction in the Yangtze Estuary, as compared to 3–45% for DNRA and 1–36% for ANAMMOX. In total, the denitrification and ANAMMOX processes removed approximately 25% of the external inorganic nitrogen transported annually into the estuary. In contrast, most external inorganic nitrogen was retained in the estuary and contributes substantially to the severe eutrophication of the Yangtze Estuary.
Methane emissions from an alpine wetland on the Tibetan Plateau: Neglected but vital contribution of the nongrowing season
Authors: Song Weimin , Wang Hao , Wang Guangshuai , Chen Litong , Jin Zhenong , Zhuang Qianlai , He Jin‐Sheng
Published: July 2015

The vast wetlands on the Tibetan Plateau are expected to be an important natural source of methane (CH4) to the atmosphere. The magnitude, patterns and environmental controls of CH4 emissions on different timescales, especially during the nongrowing season, remain poorly understood, because of technical limitations and the harsh environments. We conducted the first study on year‐round CH4 fluxes in an alpine wetland using the newly developed LI‐COR LI‐7700 open‐path gas analyzer. We found that the total annual CH4 emissions were 26.4 and 33.8 g CH4 m−2 in 2012 and 2013, respectively, and the nongrowing season CH4 emissions accounted for 43.2–46.1% of the annual emissions, highlighting an indispensable contribution that was often overlooked by previous studies. A two‐peak seasonal variation in CH4 fluxes was observed, with a small peak in the spring thawing period and a large one in the peak growing season. We detected a significant difference in the diurnal variation of CH4 fluxes between the two seasons, with two peaks in the growing season and one peak in the nongrowing season. We found that the CH4 fluxes during the growing season were well correlated with soil temperature, water table depth and gross primary production, whereas the CH4 fluxes during the nongrowing season were highly correlated with soil temperature. Our results suggested that the CH4 emission during the nongrowing season cannot be ignored and the vast wetlands on the Tibetan plateau will have the potential to exert a positive feedback on climate considering the increasing warming, particularly in the nongrowing season in this region.
A Lagrangian drop model to study warm rain microphysical processes in shallow cumulus
Authors: Naumann Ann Kristin , Seifert Axel
Published: July 2015

In this study, we introduce a Lagrangian drop (LD) model to study warm rain microphysical processes in shallow cumulus. The approach combines Large‐Eddy Simulations (LES) including a bulk microphysics parameterization with an LD model for raindrop growth. The LD model is one‐way coupled with the Eulerian LES and represents all relevant rain microphysical processes such as evaporation, accretion, and selfcollection among LDs as well as dynamical effects such as sedimentation and inertia. To test whether the LD model is fit for purpose, a sensitivity study for isolated shallow cumulus clouds is conducted. We show that the surface precipitation rate and the development of the raindrop size distribution are sensitive to the treatment of selfcollection in the LD model. Some uncertainty remains for the contribution of the subgrid‐scale turbulence to the relative velocity difference of a pair of LDs, which appears as a factor in the collision kernel. Sensitivities to other model parameters such as the initial multiplicity or the initial mass distribution are small. Overall, sensitivities of the LD model are small compared to the uncertainties in the assumptions of the bulk rain microphysics scheme, and the LD model is well suited for particle‐based studies of raindrop growth and dynamics. This opens up the opportunity to study effects like recirculation, deviations from terminal fall velocity and other microphysical phenomena that so far were not accessible for bin, bulk, or parcel models.
The change of nature and the nature of change in agricultural landscapes: Hydrologic regime shifts modulate ecological transitions
Authors: Foufoula‐Georgiou Efi , Takbiri Zeinab , Czuba Jonathan A. , Schwenk Jon
Published: July 2015

Hydrology in many agricultural landscapes around the world is changing in unprecedented ways due to the development of extensive surface and subsurface drainage systems that optimize productivity. This plumbing of the landscape alters water pathways, timings, and storage, creating new regimes of hydrologic response and driving a chain of environmental changes in sediment dynamics, nutrient cycling, and river ecology. In this work, we nonparametrically quantify the nature of hydrologic change in the Minnesota River Basin, an intensively managed agricultural landscape, and study how this change might modulate ecological transitions. During the growing season when climate effects are shown to be minimal, daily streamflow hydrographs exhibit sharper rising limbs and stronger dependence on the previous‐day precipitation. We also find a changed storage‐discharge relationship and show that the artificial landscape connectivity has most drastically affected the rainfall‐runoff relationship at intermediate quantiles. Considering the whole year, we show that the combined climate and land use change effects reduce the inherent nonlinearity in the dynamics of daily streamflow, perhaps reflecting a more linearized engineered hydrologic system. Using a simplified dynamic interaction model that couples hydrology to river ecology, we demonstrate how the observed hydrologic change and/or the discharge‐driven sediment generation dynamics may have modulated a regime shift in river ecology, namely extirpation of native mussel populations. We posit that such nonparametric analyses and reduced complexity modeling can provide more insight than highly parameterized models and can guide development of vulnerability assessments and integrated watershed management frameworks.
Microstructure and Ablation Property of a Carbon/Carbon–ZrC Composite Fabricated by Reactive Melt Infiltration with Zr/Cu Powder Mixture
Authors: Zhou Wen Yan , Ran Li Ping , Peng Ke , Ge Yi Cheng , Wu Huang , Yi Mao Zhong
Published: July 2015

A carbon/carbon–ZrC(C/C–ZrC) composite was fabricated by reactive infiltration of a Zr–40 wt% Cu powder mixture. The C/C–ZrC composite was composed of C, ZrC, and residual Cu. Continuous ZrC layers around the pyrolytic carbon and isolated ZrC particles dispersed in Cu were detected. Linear ablation rate of the composite increased with the increase of ablation time. Ablation surface of the composite was mainly composed of monoclinic ZrO2, while the quantity of Cu and Cu2O decreased with the increase of ablation time. The better ablation resistance of the C/C–ZrC composite was mainly attributed to the protective ZrO2 layer and the cooling effect of Cu.
Effective Controlling of Film Texture and Carrier Transport of a High‐Performance Polymeric Semiconductor by Magnetic Alignment
Authors: Pan Guoxing , Chen Fei , Hu Lin , Zhang Kejun , Dai Jianming , Zhang Fapei
Published: July 2015

The controlling of molecular orientation and structural ordering of organic semiconductors is crucial to achieve high performance electronic devices. In this work, large‐area highly oriented and ordered films of an excellent electron transporter Poly{[N,N′‐bis(2‐octyldodecyl)‐1,4,5,8‐naphthalenedicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)} (P(NDI2OD‐T2)) are achieved by improved solution‐cast in high magnetic field. Microstructural characterizations reveal that the chain backbones of P(NDI2OD‐T2) are highly aligned along the applied magnetic field in the films. Based on the synchrotron‐based X‐ray diffraction analysis of the polymer films cast from different solvents, a mechanism which controls the alignment process is proposed, which emphasizes that molecular aggregates of P(NDI2OD‐T2) preformed in the solution initiate magnetic alignment and finally determine the degree of film texture. Furthermore, the time‐modulated magnetic field technique is utilized to effectively control the orientation of π‐conjugated plane of the backbones, thus the degree of face‐on molecular packing of P(NDI2OD‐T2) is enhanced significantly. Thin film transistors based on the magnetic‐aligned P(NDI2OD‐T2) films exhibit an enhancement of electron mobility by a factor of four compared to the unaligned devices, as well as a large mobility anisotropy of seven.
Luminescent Silicon Diatom Replicas: Self‐Reporting and Degradable Drug Carriers with Biologically Derived Shape for Sustained Delivery of Therapeutics
Authors: Maher Shaheer , Alsawat Mohammed , Kumeria Tushar , Fathalla Dina , Fetih Gihan , Santos Abel , Habib Fawzia , Losic Dusan
Published: July 2015

Current development of drug microcarriers is mainly based on spherical shapes, which are not biologically favorable geometries for complex interactions with biological systems. Scalable synthesis of drug carriers with nonspherical and anisotropic shapes featuring sustained drug‐releasing performances, biocompatibility, degradability, and sensing capabilities is challenging. These challenges are addressed in this work by employing Nature's optimized designs obtained from low‐cost diatomaceous earth mineral derived from single‐cell algae diatoms. Silica diatoms with unique shapes and 3D microcapsule morphology are converted into silicon diatom replicas with identical structure by a magnesiothermic reduction process. The results reveal that prepared silicon diatoms have a set of unique properties including favorable microcapsule structure with high surface area and micro/mesoporosity providing high drug loading, fast biodegradability, and intrinsic luminescence, which make them highly suitable for low‐cost production of advanced drug microcarriers. Their sustained drug release >30 days combined with self‐reporting function based on silicon luminescence properties using nonluminescent and luminescent drugs for intravitreal drug therapy is successfully demonstrated. These silicon diatoms offer promising potential toward scalable production of low‐cost and advanced microcarriers for broad medical therapies, including theranostics and microrobotic guided drug delivery devices.
Development of a Multifunctional Platform Based on Strong, Intrinsically Photoluminescent and Antimicrobial Silica‐Poly(citrates)‐Based Hybrid Biodegradable Elastomers for Bone Regeneration
Authors: Du Yuzhang , Yu Meng , Ge Juan , Ma Peter X. , Chen Xiaofeng , Lei Bo
Published: July 2015

Biodegradable biomaterials with intrinsically multifunctional properties such as high strength, photoluminescent ability (bioimaging monitoring), and antimicrobial activity (anti‐infection), as well as high osteoblastic differentiation ability, play a critical role in successful bone tissue regeneration. However, fabricating a biomaterial containing all these functions is still a challenge. Here, urethane cross‐linked intrinsically multifunctional silica‐poly(citrate) (CMSPC)‐based hybrid elastomers are developed by first one‐step polymerization and further chemical crosslinked using isocyanate. CMSPC hybrid elastomers demonstrate a high modulus of 976 ± 15 MPa, which is superior compared with most conventional poly(citrate)‐based elastomers. Hybrid elastomers show strong and stable intrinsic photoluminescent ability (emission 400–600 nm) due to the incorporation of silica phase. All elastomers exhibit high inherent antibacterial properties against Staphylococcus aureus. In addition, CMSPC hybrid elastomers significantly enhance the proliferation and metabolic activity of osteoblasts (MC3T3‐E1). CMSPC hybrid elastomers significantly promote the osteogenic differentiation of MC3T3‐E1 by improving alkaline phosphatase activity and calcium biomineralization deposits, as well as expressions of osteoblastic genes. These hybrid elastomers also show a minimal inflammatory response indicated by subcutaneous transplantation in vivo. These optimized structure and multifunctional properties make this hybrid elastomer highly promising for bone tissue regeneration and antiinfection and bioimaging applications.
Vectorially Imprinted Hybrid Nanofilm for Acetylcholinesterase Recognition
Authors: Jetzschmann Katharina J. , Jágerszki Gyula , Dechtrirat Decha , Yarman Aysu , Gajovic‐Eichelmann Nenad , Gilsing Hans‐Detlev , Schulz Burkhard , Gyurcsányi Róbert E. , Scheller Frieder W.
Published: July 2015

Effective recognition of enzymatically active tetrameric acetylcholinesterase (AChE) is accomplished by a hybrid nanofilm composed of a propidium‐terminated self‐assembled monolayer (Prop‐SAM) which binds AChE via its peripheral anionic site (PAS) and an ultrathin electrosynthesized molecularly imprinted polymer (MIP) cover layer of a novel carboxylate‐modified derivative of 3,4‐propylenedioxythiophene. The rebinding of the AChE to the MIP/Prop‐SAM nanofilm covered electrode is detected by measuring in situ the enzymatic activity. The oxidative current of the released thiocholine is dependent on the AChE concentration from ≈0.04 × 10−6 to 0.4 × 10−6m. An imprinting factor of 9.9 is obtained for the hybrid MIP, which is among the best values reported for protein imprinting. The dissociation constant characterizing the strength of the MIP‐AChE binding is 4.2 × 10−7m indicating the dominant role of the PAS‐Prop‐SAM interaction, while the benefit of the MIP nanofilm covering the Prop‐SAM layer is the effective suppression of the cross‐reactivity toward competing proteins as compared with the Prop‐SAM. The threefold selectivity gain provided by i) the “shape‐specific” MIP filter, ii) the propidium‐SAM, iii) signal generation only by the AChE bound to the nanofilm shows promise for assessing AChE activity levels in cerebrospinal fluid.
Study of Configuration Differentia and Highly Efficient, Deep‐Blue, Organic Light‐Emitting Diodes Based on Novel Naphtho[1,2‐d]imidazole Derivatives
Authors: Liu Ming , Li Xiang‐Long , Chen Dong Cheng , Xie Zhongzhi , Cai Xinyi , Xie Gaozhan , Liu Kunkun , Tang Jianxin , Su Shi‐Jian , Cao Yong
Published: July 2015

Two novel naphtho[1,2‐d]imidazole derivatives are developed as deep‐blue, light‐emitting materials for organic light‐emitting diodes (OLEDs). The 1H‐naphtho[1,2‐d]imidazole based compounds exhibit a significantly superior performance than the 3H‐naphtho[1,2‐d]imidazole analogues in the single‐layer devices. This is because they have a much higher capacity for direct electron‐injection from the cathode compared to their isomeric counterparts resulting in a ground‐breaking EQE (external quantum efficiency) of 4.37% and a low turn‐on voltage of 2.7 V, and this is hitherto the best performance for a non‐doped single‐layer fluorescent OLED. Multi‐layer devices consisting of both hole‐ and electron‐transporting layers, result in identically excellent performances with EQE values of 4.12–6.08% and deep‐blue light emission (Commission Internationale de l'Eclairage (CIE) y values of 0.077–0.115) is obtained for both isomers due to the improved carrier injection and confinement within the emissive layer. In addition, they showed a significantly better blue‐color purity than analogous molecules based on benzimidazole or phenanthro[9,10‐d]imidazole segments.
Uncooled Carbon Nanotube Photodetectors
Authors: He Xiaowei , Léonard François , Kono Junichiro
Published: July 2015

Photodetectors play key roles in many applications such as remote sensing, night vision, reconnaissance, medical imaging, thermal imaging, and chemical detection. Several properties such as performance, reliability, ease of integration, cost, weight, and form factor are all important in determining the attributes of photodetectors for particular applications. While a number of materials have been used over the past several decades to address photo­detection needs across the electromagnetic spectrum, the advent of nanomaterials opens new possibilities for photodetectors. In particular, carbon‐based nanomaterials such as carbon nanotubes (CNTs) and graphene possess unique properties that have recently been explored for photodetectors. Here, the status of the field is reviewed, presenting a broad coverage of the different types of photodetectors that have been realized with CNTs, placing particular emphasis on the types of mechanisms that govern their operation. A comparative summary is presented of the main performance metrics for such detectors, and an outlook for performance improvements.
Spatially Confined MnO2 Nanostructure Enabling Consecutive Reversible Charge Transfer from Mn(IV) to Mn(II) in a Mixed Pseudocapacitor‐Battery Electrode
Authors: Weng Yu‐Ting , Pan Hsiao‐An , Lee Rung‐Chuan , Huang Tzu‐Yang , Chu Yun , Lee Jyh‐Fu , Sheu Hwo‐Shuenn , Wu Nae‐Lih
Published: July 2015

Mn oxides are highly important electrode materials for aqueous electrochemical energy storage devices, including batteries and supercapacitors. Although MnO2 is a promising pseudocapacitor material because of its outstanding rate and capacity performance, its electrochemical instability in aqueous electrolyte prevents its use at low electrochemical potential. Here, the possibility of stabilizing MnO2 electrode using SiO2‐confined nanostructure is demonstrated. Remarkably, an exceptionally good electrochemical stability under large negative polarization in aqueous (Li2SO4) electrolyte, usually unattainable for MnO2‐based electrode, is achieved. Even more interestingly, this MnO2–SiO2 nanostructured composite exhibits unique mixed pseudocapacitance‐battery behaviors involving consecutive reversible charge transfer from Mn(IV) to Mn(II), which enable simultaneous high‐capacity and high‐rate characteristics, via different charge‐transfer kinetic mechanisms. This suggests a strategy to design and stabilize electrochemical materials that are comprised of intrinsically unstable but high‐performing component materials.
Three‐Dimensional Smart Catalyst Electrode for Oxygen Evolution Reaction
Authors: Chen Sheng , Duan Jingjing , Bian Pengju , Tang Youhong , Zheng Rongkun , Qiao Shi‐Zhang
Published: July 2015

A multifunctional catalyst electrode mimicking external stimuli–responsive property has been prepared by the in situ growth of nitrogen (N)‐doped NiFe double layered hydroxide (N–NiFe LDH) nanolayers on a 3D nickel foam substrate framework. The electrode demonstrates superior performance toward catalyzing oxygen evolution reaction (OER), affording a low overpotential of 0.23 V at the current density of 10 mA cm−2, high Faradaic efficiency of ≈98%, and stable operation for >60 h. Meanwhile, the electrode can dynamically change its color from gray silver to dark black with the OER happening, and the coloration/bleaching processes persist for at least 5000 cycles, rendering it a useful tool to monitor the catalytic process. Mechanism study reveals that the excellent structural properties of electrode such as 3D conductive framework, ultra thickness of N–NiFe LDH nanolayer (≈0.8 nm), and high N‐doping content (≈17.8%) make significant contribution to achieving enhanced catalytic performance, while N–NiFe LDH nanolayer on electrode is the main contributor to the stimuli‐responsive property with the reversible extraction/insertion of electrons from/into N–NiFe LDH leading to the coloration/bleaching processes. Potential application of this electrode has been further demonstrated by integrating it into a Zn–air battery device to identify the charging process during electrochemical cycling.
All‐Solid‐State Lithium‐Ion Microbatteries Using Silicon Nanofilm Anodes: High Performance and Memory Effect
Authors: Cras Frédéric Le , Pecquenard Brigitte , Dubois Vincent , Phan Viet‐Phong , Guy‐Bouyssou Delphine
Published: July 2015

All‐solid‐state thin film lithium batteries are promising devices to power the next generations of autonomous microsystems. Nevertheless, some industrial constraints such as the resistance to reflow soldering (260 °C) and to short‐circuiting necessitate the replacement of the lithium anode. In this study, a 2 V lithium‐ion system based on amorphous silicon nanofilm anodes (50–200 nm thick), a LiPON electrolyte, and a new lithiated titanium oxysulfide cathode Li1.2TiO0.5S2.1 is prepared by sputtering. The determination of the electrochemical behavior of each active material and of whole systems with different configurations allows the highlighting of the particular behavior of the LixSi electrode and the understanding of its consequences on the performance of Li‐ion cells. Lithium‐ion microbatteries processed with industrial tools and embedded in microelectronic packages exhibit particularly high cycle life (−0.006% cycle−1), ultrafast charge (80% capacity in 1 min), and tolerate both short‐circuiting and reflow soldering. Moreover, the perfect stability of the system allows the assignment of some modifications of the voltage curve and a slow and reversible capacity fade occurring in specific conditions, to the formation of Li15Si4 and to the expression of a “memory effect.” These new findings will help to optimize the design of future Li‐ion systems using nanosized silicon anodes.
New suggestive genetic loci and biological pathways for attention function in adult attention‐deficit/hyperactivity disorder
Authors: Alemany Silvia , Ribasés Marta , Vilor‐Tejedor Natàlia , Bustamante Mariona , Sánchez‐Mora Cristina , Bosch Rosa , Richarte Vanesa , Cormand Bru , Casas Miguel , Ramos‐Quiroga Josep A. , Sunyer Jordi
Published: July 2015

Attention deficit is one of the core symptoms of the attention‐deficit/hyperactivity disorder (ADHD). However, the specific genetic variants that may be associated with attention function in adult ADHD remain largely unknown. The present study aimed to identifying SNPs associated with attention function in adult ADHD and tested whether these associations were enriched for specific biological pathways. Commissions, hit‐reaction time (HRT), the standard error of HRT (HRTSE), and intraindividual coefficient variability (ICV) of the Conners Continuous Performance Test (CPT‐II) were assessed in 479 unmedicated adult ADHD individuals. A Genome‐Wide Association Study (GWAS) was conducted for each outcome and, subsequently, gene set enrichment analyses were performed. Although no SNPs reached genome‐wide significance (P < 5E−08), 27 loci showed suggestive evidence of association with the CPT outcomes (P < E−05). The most relevant associated SNP was located in the SORCS2 gene (P = 3.65E−07), previously associated with bipolar disorder (BP), Alzheimer disease (AD), and brain structure in elderly individuals. We detected other genes suggested to be involved in synaptic plasticity, cognitive function, neurological and neuropsychiatric disorders, and smoking behavior such as NUAK1, FGF20, NETO1, BTBD9, DLG2, TOP3B, and CHRNB4. Also, several of the pathways nominally associated with the CPT outcomes are relevant for ADHD such as the ubiquitin proteasome, neurodegenerative disorders, axon guidance, and AD amyloid secretase pathways. To our knowledge, this is the first GWAS and pathway analysis of attention function in patients with persistent ADHD. Overall, our findings reinforce the conceptualization of attention function as a potential endophenotype for studying the molecular basis of adult ADHD. © 2015 Wiley Periodicals, Inc.
Locating chimpanzee nests and identifying fruiting trees with an unmanned aerial vehicle
Authors: van Andel Alexander C. , Wich Serge A. , Boesch Christophe , Koh Lian Pin , Robbins Martha M. , Kelly Joseph , Kuehl Hjalmar S.
Published: July 2015

Monitoring of animal populations is essential for conservation management. Various techniques are available to assess spatiotemporal patterns of species distribution and abundance. Nest surveys are often used for monitoring great apes. Quickly developing technologies, including unmanned aerial vehicles (UAVs) can be used to complement these ground‐based surveys, especially for covering large areas rapidly. Aerial surveys have been used successfully to detect the nests of orang‐utans. It is unknown if such an approach is practical for African apes, which usually build their nests at lower heights, where they might be obscured by forest canopy. In this 2‐month study, UAV‐derived aerial imagery was used for two distinct purposes: testing the detectability of chimpanzee nests and identifying fruiting trees used by chimpanzees in Loango National Park (Gabon). Chimpanzee nest data were collected through two approaches: we located nests on the ground and then tried to detect them in UAV photos and vice versa. Ground surveys were conducted using line transects, reconnaissance trails, and opportunistic sampling during which we detected 116 individual nests in 28 nest groups. In complementary UAV images we detected 48% of the individual nests (68% of nest groups) in open coastal forests and 8% of individual nests (33% of nest groups) in closed canopy inland forests. The key factor for nest detectability in UAV imagery was canopy openness. Data on fruiting trees were collected from five line transects. In 122 UAV images 14 species of trees (N = 433) were identified, alongside 37 tree species (N = 205) in complementary ground surveys. Relative abundance of common tree species correlated between ground and UAV surveys. We conclude that UAVs have great potential as a rapid assessment tool for detecting chimpanzee presence in forest with open canopy and assessing fruit tree availability. UAVs may have limited applicability for nest detection in closed canopy forest. Am. J. Primatol. 77:1122–1134, 2015. © 2015 Wiley Periodicals, Inc.
Quantitative diet reconstruction of a Neolithic population using a Bayesian mixing model (FRUITS): The case study of Ostorf (Germany)
Authors: Fernandes Ricardo , Grootes Pieter , Nadeau Marie‐Josée , Nehlich Olaf
Published: July 2015

Objectives

The island cemetery site of Ostorf (Germany) consists of individual human graves containing Funnel Beaker ceramics dating to the Early or Middle Neolithic. However, previous isotope and radiocarbon analysis demonstrated that the Ostorf individuals had a diet rich in freshwater fish. The present study was undertaken to quantitatively reconstruct the diet of the Ostorf population and establish if dietary habits are consistent with the traditional characterization of a Neolithic diet.

Methods

Quantitative diet reconstruction was achieved through a novel approach consisting of the use of the Bayesian mixing model Food Reconstruction Using Isotopic Transferred Signals (FRUITS) to model isotope measurements from multiple dietary proxies (δ13Ccollagen, δ15Ncollagen, δ13Cbioapatite, δ34Smethione,14Ccollagen). The accuracy of model estimates was verified by comparing the agreement between observed and estimated human dietary radiocarbon reservoir effects.

Results

Quantitative diet reconstruction estimates confirm that the Ostorf individuals had a high protein intake due to the consumption of fish and terrestrial animal products. However, FRUITS estimates also show that plant foods represented a significant source of calories. Observed and estimated human dietary radiocarbon reservoir effects are in good agreement provided that the aquatic reservoir effect at Lake Ostorf is taken as reference.

Conclusions

The Ostorf population apparently adopted elements associated with a Neolithic culture but adapted to available local food resources and implemented a subsistence strategy that involved a large proportion of fish and terrestrial meat consumption. This case study exemplifies the diversity of subsistence strategies followed during the Neolithic. Am J Phys Anthropol 158:325–340, 2015. © 2015 Wiley Periodicals, Inc.
Abnormal ranges of vital signs in children in Japanese prehospital settings
Authors: Nosaka Nobuyuki , Muguruma Takashi , Knaup Emily , Tsukahara Kohei , Enomoto Yuki , Kaku Noriyuki
Published: July 2015

Aim

The revised Fire Service Law obliges each prefectural government in Japan to establish a prehospital acuity scale. The Foundation for Ambulance Service Development (FASD) created an acuity scale for use as a reference. Our preliminary survey revealed that 32 of 47 prefectures directly applied the FASD scale for children. This scale shows abnormal ranges of heart rate and respiratory rate in young children. This study aimed to evaluate the validity of the abnormal ranges on the FASD scale to assess its overall performance for triage purposes in paediatric patients.

Methods

We evaluated the validity of the ranges by comparing published centile charts for these vital signs with records of 1,296 ambulance patients.

Results

A large portion of the abnormal ranges on the scale substantially overlapped with the normal centile charts. Triage decisions using the FASD scale of vital signs properly classified 22% (n = 287) of children. The sensitivity and specificity for high urgency were as high as 91% (95% confidence interval, 82–96%) and as low as 18% (95% confidence interval, 16–20%).

Conclusion

We found there is room for improvement of the abnormal ranges on the FASD scale.
Visible‐light photocatalytic activity of Ag@MIL‐125(Ti) microspheres
Authors: Guo Hongxu , Guo Di , Zheng Zishan , Weng Wen , Chen Jianhua
Published: July 2015

Ag nanoparticle (NP)‐decorated MIL‐125(Ti) microspheres (Ag@MIL‐125(Ti)) were firstly fabricated via a facile hydrothermal and following photo‐reduction method. The photocatalysts were characterized using X‐ray diffraction, scanning and transmission electron microscopies, X‐ray photoelectron spectroscopy and UV–visible diffuse reflectance spectroscopy. The characterization results indicated that Ag NPs were dispersed on the surface of MIL‐125(Ti) microspheres, and the Ag NPs had a uniform diameter of about 40 nm. The composites exhibited excellent visible‐light absorption, due to the modification with the Ag NPs. The photocatalytic activity for the visible‐light‐promoted degradation of Rhodamine B was improved through the optimization of the amount of Ag loaded as a co‐catalyst, this amount being determined as 3 wt%. Additionally, studies performed using radical scavengers indicated that O2− and e− served as the main reactive species. The catalyst can be reused at least five times without significant loss of its catalytic activity. Furthermore, a photocatalytic mechanism for degradation of organics over Ag@MIL‐125(Ti) is also proposed. Copyright © 2015 John Wiley & Sons, Ltd.
Influences of pre‐ordered melt structures on the crystallization behavior and polymorphic composition of β‐nucleated isotactic polypropylene with different stereo‐defect distribution
Authors: Kang Jian , Weng Gengsheng , Chen Jinyao , Yang Feng , Cao Ya , Xiang Ming
Published: July 2015

As part of continuous efforts to understand the surprising synergetic effect between β‐nucleating agent and pre‐ordered structures of isotactic polypropylene (iPP) in significant enhancement of β‐crystallization (Ordered Structure Effect, OSE), two β‐nucleated iPP with different uniformities of stereo‐defect distribution (WPP‐A and WPP‐B) were prepared, their crystallization behaviors with variation of melt structures were studied in detail. The results revealed that β‐phase can hardly form in WPP‐A (whose stereo‐defect distribution is less uniform) because of its strong tendency of α‐nucleation caused by its less uniform stereo‐defect distribution, while WPP‐B is more favorable for β‐crystallization; As fusion temperature decreases, similar variation trends of crystallization temperature and β‐phase proportion can be observed from WPP‐A and WPP‐B, indicating the occurrence of OSE behavior, which provides unsurpassed β‐nucleation efficiency and induces β‐crystallization even in WPP‐A which is less favorable for β‐crystallization; moreover, the upper and lower limiting temperatures of Region II of WPP‐A and WPP‐B are identical, suggesting the uniformity of stereo‐defect distribution has little influence on temperature window for OSE (denoted as Region II). To explore the physical nature of Region II, self‐nucleation behavior and equilibrium melting temperature
of PP‐A and PP‐B were studied. The lower limiting temperatures of exclusive self‐nucleation domain of both PP‐A and PP‐B are identical with the lower limiting temperatures of Region II in OSE (168°C); moreover, the Tm0 of both PP‐A and PP‐B are close to their upper limiting temperatures of Region II in OSE behavior (189°C). The possible explanation was proposed. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42632.
Reactive extrusion effects on rheological and mechanical properties of poly(lactic acid)/poly[(butylene succinate)‐co‐adipate]/epoxy chain extender blends and clay nanocomposites
Authors: Mirzadeh Amin , Ghasemi Hesam , Mahrous Fatma , Kamal Musa R.
Published: July 2015

Poly(lactic acid) (PLA), a biosource, biodegradable polymer, is not suitable for some important polymer processing operations, such as film blowing and blow molding, due to its low melt strength. Moreover, while it has high tensile modulus and strength in the solid state, it exhibits low ductility. The present work is an extension of our earlier effort to improve the processability and mechanical properties of PLA by blending with poly[(butylene succinate)‐co‐adipate)] (PBSA), a biodegradable polymer with lower glass transition temperature. We evaluate the influences of incorporation of an epoxy chain extender and nanoclay on the properties of the blend. Since earlier work was conducted in a batch mixer, the influence of melt processing in the twin screw extruder and the differences between products obtained in the extruder and the batch mixer are evaluated and explained. Based on earlier work, the following PLA/PBSA blend ratios of 90:10, 80:20 and 70:30 were selected. All the samples were prepared in the twin‐screw extruder at two different screw speeds (50 and 150 rpm), to evaluate the effects of residence time and shear rates. The morphology and structure of the blends were examined using field emission scanning electron microscopy. Transmission electron microscopy (TEM) and X‐ray diffraction (XRD) were used to evaluate the levels of intercalation and exfoliation in the nanocomposites. The chain extension reaction was evaluated using nuclear magnetic resonance (NMR) spectroscopy and other techniques. Rheological properties (dynamic oscillatory shear and elongational viscosity measurements) and mechanical characteristics of the pure components, blends, and nanocomposites were studied and discussed in light of the composition and morphology of the blends and the nanocomposites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42664.
Boronic Acid‐Based Carbohydrate Sensing
Authors: Zhai Wenlei , Sun Xiaolong , James Tony D. , Fossey John S.
Published: July 2015

The covalent boron–diol interaction enables elaborate design of boronic acid‐based saccharide sensors. Over the last decade, this research topic has been well developed thanks to the integration of boronic acid chemistry with a range of techniques, including supramolecular chemistry, materials chemistry, surface modification, and nanotechnology. New sensing strategies and platforms have been introduced and remarkable progress has been achieved to fully utilize the unique property of boron–diol interaction and to improve the binding affinity towards different targets, especially under physiological conditions. In this review, the latest progress over the past 30 months (from late 2012 to early 2015) is highlighted and discussed to shed light on this versatile and promising platform for saccharide sensing.