bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitrous oxide during the onset of the Atlantic cold tongue
Authors: Arévalo‐Martínez D. L. , Kock A. , Steinhoff T. , Brandt P. , Dengler M. , Fischer T. , Körtzinger A. , Bange H. W.
Published: November 2016

The tropical Atlantic exerts a major influence in climate variability through strong air‐sea interactions. Within this region, the eastern side of the equatorial band is characterized by strong seasonality, whereby the most prominent feature is the annual development of the Atlantic cold tongue (ACT). This band of low sea surface temperatures (∼22–23°C) is typically associated with upwelling‐driven enhancement of surface nutrient concentrations and primary production. Based on a detailed investigation of the distribution and sea‐to‐air fluxes of N2O in the eastern equatorial Atlantic (EEA), we show that the onset and seasonal development of the ACT can be clearly observed in surface N2O concentrations, which increase progressively as the cooling in the equatorial region proceeds during spring‐summer. We observed a strong influence of the surface currents of the EEA on the N2O distribution, which allowed identifying “high” and “low” concentration regimes that were, in turn, spatially delimited by the extent of the warm eastward‐flowing North Equatorial Countercurrent and the cold westward‐flowing South Equatorial Current. Estimated sea‐to‐air fluxes of N2O from the ACT (mean 5.18 ± 2.59 μmol m−2 d−1) suggest that in May–July 2011 this cold‐water band doubled the N2O efflux to the atmosphere with respect to the adjacent regions, highlighting its relevance for marine tropical emissions of N2O.
Seasonal variability of warm boundary layer cloud and precipitation properties in the Southern Ocean as diagnosed from A‐Train data
Authors: Mace Gerald G. , Avey Stephanie
Published: November 2016

The extensive cloudiness and resulting high albedo of the Southern Oceans (SO) are predominantly due to the occurrence of widespread marine boundary layer clouds. Recent work finds correlations between biogenically enhanced cloud condensation nuclei concentrations and cloud droplet number concentrations derived from passive satellite data. The active remote sensors in the A‐Train have created a unique and long‐term record of these clouds that include vertical profiles of radar reflectivity and microwave brightness temperature from CloudSat that can be combined with solar reflectances from Moderate Resolution Imaging Spectroradiometer. We examine this data record using a unique algorithm to infer warm‐topped cloud and precipitation properties. We find seasonal variations in cloud properties where summer season clouds demonstrate higher cloud droplet number concentrations on average and require higher liquid water contents to produce similar precipitation rates.
Regional Bowen ratio controls on afternoon moist convection: A large eddy simulation study
Authors: Kang Song‐Lak
Published: November 2016

This study examines the effect of the regional Bowen ratio β, the ratio of the domain‐averaged surface sensible heat flux (SHF) to latent heat flux (LHF), on afternoon moist convection. With a temporally evolving but spatially uniform surface available energy over a mesoscale domain under a weak capping inversion, we run large eddy simulation of the afternoon convective boundary layer (CBL). We first prescribe a small β of 0.56 (a wet surface) and then the reversed large β of 1.80 (a dry surface) by switching the SHF and LHF fields. The perturbation fields of the fluxes are prescribed with the Fourier spectra of κ− 3 (κ is horizontal wave number; strong mesoscale heterogeneity) and κ0 (homogeneity). The large β cases have strong vertical buoyancy fluxes and produce more vigorous updrafts. In the heterogeneous, large β surface case, with the removal of convective inhibition over a mesoscale subdomain of large SHF, deep convection develops. In the heterogeneous, small β surface case, convective clouds develop but do not progress into precipitating convection. In the homogeneous surface cases, randomly distributed shallow clouds develop with significantly more and thicker clouds in the large β case. (Co)spectral analyses confirm the more vigorous turbulent thermals in the large β cases and reveal that the moisture advection by the surface heterogeneity‐induced mesoscale flows makes the correlation between mesoscale temperature and moisture perturbations change from negative to positive, which facilitates the mesoscale pool of high relative humidity air just above the CBL top, a necessary condition for deep convection.
Spatial extent and temporal variability of Greenland firn aquifers detected by ground and airborne radars
Authors: Miège Clément , Forster Richard R. , Brucker Ludovic , Koenig Lora S. , Solomon D. Kip , Paden John D. , Box Jason E. , Burgess Evan W. , Miller Julie Z. , McNerney Laura , Brautigam Noah , Fausto Robert S. , Gogineni Sivaprasad
Published: November 2016

We document the existence of widespread firn aquifers in an elevation range of ~1200–2000 m, in the high snow‐accumulation regions of the Greenland ice sheet. We use NASA Operation IceBridge accumulation radar data from five campaigns (2010–2014) to estimate a firn‐aquifer total extent of 21,900 km2. We investigate two locations in Southeast Greenland, where repeated radar profiles allow mapping of aquifer‐extent and water table variations. In the upper part of Helheim Glacier the water table rises in spring following above‐average summer melt, showing the direct firn‐aquifer response to surface meltwater production changes. After spring 2012, a drainage of the firn‐aquifer lower margin (5 km) is inferred from both 750 MHz accumulation radar and 195 MHz multicoherent radar depth sounder data. For 2011–2014, we use a ground‐penetrating radar profile located at our Ridgeline field site and find a spatially stable aquifer with a water table fluctuating less than 2.5 m vertically. When combining radar data with surface topography, we find that the upper elevation edge of firn aquifers is located directly downstream of locally high surface slopes. Using a steady state 2‐D groundwater flow model, water is simulated to flow laterally in an unconfined aquifer, topographically driven by ice sheet surface undulations until the water encounters crevasses. Simulations suggest that local flow cells form within the Helheim aquifer, allowing water to discharge in the firn at the steep‐to‐flat transitions of surface topography. Supported by visible imagery, we infer that water drains into crevasses, but its volume and rate remain unconstrained.
Hyporheic flow and dissolved oxygen distribution in fish nests: The effects of open channel velocity, permeability patterns, and groundwater upwelling
Authors: Cardenas M. Bayani , Ford Aimee E. , Kaufman Matthew H. , Kessler Adam J. , Cook Perran L. M.
Published: November 2016

Many fish lay their eggs in nests, or redds, which they construct in sediment. The viability of eggs depends on many factors, particularly their oxygenation. Because dissolved oxygen is typically saturated within the stream channel, the dissolved oxygen distribution within the redd depends on whether or not hyporheic flow and transport occur within the sediment. We conducted a series of flume and numerical flow and age transport modeling experiments with the aim of understanding the effects of salmonid redds on the hyporheic transport of young oxygenated water. Hyporheic flow was visualized directly through dye injections. Dissolved oxygen throughout the fish nest was measured using a planar optode. Experiments were conducted at various open channel flow velocities in order to understand their effect on dissolved oxygen, and computational simulations considered various sediment textures and ambient groundwater upwelling rates to add process‐level insight. We found that, as also shown by previous studies, the redd topography induces multiscale hyporheic flow that effectively flushes the egg pocket location with younger presumably oxygenated water; older water upwells and forms anoxic zones. This pattern persists even at the lowest channel flow rates and at small upwelling velocities of older ambient groundwater which splits the multiscale hyporheic flow cells into isolated pockets. Large groundwater upwelling rates can shut down all the hyporheic flushing. The relatively coarse texture of the redd further promotes hyporheic flushing of the redd sediment with oxygenated water. Thus, redd morphology and sediment texture optimally combine to induce hyporheic exchange flow that delivers young oxygenated water to the egg pocket.
Thermal alteration of water extractable organic matter in climosequence soils from the Sierra Nevada, California
Authors: Santos Fernanda , Russell David , Berhe Asmeret Asefaw
Published: November 2016

In the next decades, the influence of wildfires in controlling the cycling and composition of soil organic matter (SOM) globally and in the western U.S. is expected to grow. While the impact of fires on bulk SOM has been extensively studied, the extent at which heating of soil affects the soluble component of SOM remains unclear. Here we investigated the thermal transformations of water‐extractable organic matter (WEOM) by examining the changes in the distribution of carbon (C) functional groups in WEOM from soils heated at low and intermediate temperatures. WEOM (<0.7 µm particle size) was extracted from topsoils (0–5 cm depth) of five soil series formed from a nonglaciated granitic bedrock and sampled along a Sierra Nevada climosequence. Soils were heated in a muffle furnace at 150°C, 250°C, and 350°C for 1 h. The extracted solution was analyzed for WEOM aromaticity, mean molecular weight, organic C (OC) concentration, and major structural components by employing optical spectrophotometry and liquid‐state 1H‐NMR spectroscopy. At 150°C and 250°C, OC concentrations increased relative to the thermally unaltered samples, with losses of oxygenated functional C groups and enrichment of aliphatic C structures observed at 250°C. Conversely, OC concentration and mean molecular weight decreased as heating increased from 250°C to 350°C, whereas WEOC became more enriched in aromatic C structures. Our results suggest that low and intermediate fire intensities significantly alter the nature of dissolved organic matter exported from soils to rivers in the Sierra Nevada and beyond.
Simulating county‐level crop yields in the Conterminous United States using the Community Land Model: The effects of optimizing irrigation and fertilization
Authors: Leng Guoyong , Zhang Xuesong , Huang Maoyi , Yang Qichun , Rafique Rashid , Asrar Ghassem R. , Ruby Leung L.
Published: November 2016

In this study, we applied version 4.5 of the Community Land Model (CLM) at a 0.125° resolution to provide the first county‐scale model validation for simulating crop yields over the Conterminous United States (CONUS). Large bias was found in simulating crop yields against U.S. Department of Agriculture (USDA) survey data, with county‐level root‐mean‐square error (RMSE) of 42% and 38% for simulated US mean corn and soybean yields, respectively. We then synthesized crop yield, irrigation and fertilization data sets from USDA and U.S. Geological Survey (USGS) to constrain model simulations. Compared with fertilization, irrigation has limited effects on crop yields with improvements limited to irrigated regions. In most current‐generation Earth system models (ESMs), fertilizers are applied spatially uniformly with fixed amounts and timing without considering crop fertilizer demand. To address this weakness, we propose a prognostic fertilization scheme that dynamically determines the timing and rate of each fertilizer application, with the annual amounts and valid fertilization time windows constrained by surveyed data. The optimized fertilization scheme reduces RMSE to 22% and 21% of the US mean corn and soybean yields, respectively. Compared with the default CLM4.5, our fertilization scheme substantially improves crop yield simulations especially over major crop growing regions. However, to compensate for the widely documented biases in denitrification rates simulated by CLM4.5, the dynamically determined fertilization timing and rates do not match the fertilization practices of farmers exactly. Therefore, caution should be exercised when extending this method beyond the contemporary conditions.
Improved seasonal prediction using the SINTEX‐F2 coupled model
Authors: Doi Takeshi , Behera Swadhin K. , Yamagata Toshio
Published: November 2016

The SINTEX‐F1 Coupled General Circulation Model (CGCM) was developed within the EU‐Japan collaborative framework to study global climate variability and its predictability by use of the Earth Simulator. The seasonal prediction system based on the SINTEX‐F1 has demonstrated its outstanding performance of predicting El Niño/Southern Oscillation (ENSO) and the Indian Ocean Dipole since 2005. However, there is much room for improvement in predicting extratropical climate variations. To deal with this, a revised CGCM called SINTEX‐F2 has been developed; the new system is a high‐resolution version with a dynamical sea‐ice model. For the tropical climate variations in the Pacific and the Indian Ocean, the SINTEX‐F2 preserves the high‐prediction skill, and sometimes even shows higher skill especially for strong events, as compared to the SINTEX‐F1. In addition, it has turned out that the new system is more skillful in predicting the subtropics, particularly, the Indian Ocean Subtropical Dipole and the Ningaloo Niño. The improvement may contribute to enhancing prediction skills of the regional rainfall distributions and encourage us to develop an early warning system which may be applied for societal and industrial activities.
The tropical rain belts with an annual cycle and a continent model intercomparison project: TRACMIP
Authors: Voigt Aiko , Biasutti Michela , Scheff Jacob , Bader Jürgen , Bordoni Simona , Codron Francis , Dixon Ross D. , Jonas Jeffrey , Kang Sarah M. , Klingaman Nicholas P. , Leung Ruby , Lu Jian , Mapes Brian , Maroon Elizabeth A. , McDermid Sonali , Park Jong‐yeon , Roehrig Romain , Rose Brian E. J. , Russell Gary L. , Seo Jeongbin , Toniazzo Thomas , Wei Ho‐Hsuan , Yoshimori Masakazu , Vargas Zeppetello Lucas R.
Published: November 2016

This paper introduces the Tropical Rain belts with an Annual cycle and a Continent Model Intercomparison Project (TRACMIP). TRACMIP studies the dynamics of tropical rain belts and their response to past and future radiative forcings through simulations with 13 comprehensive and one simplified atmosphere models coupled to a slab ocean and driven by seasonally varying insolation. Five idealized experiments, two with an aquaplanet setup and three with a setup with an idealized tropical continent, fill the space between prescribed‐SST aquaplanet simulations and realistic simulations provided by CMIP5/6. The simulations reproduce key features of present‐day climate and expected future climate change, including an annual‐mean intertropical convergence zone (ITCZ) that is located north of the equator and Hadley cells and eddy‐driven jets that are similar to present‐day climate. Quadrupling CO2 leads to a northward ITCZ shift and preferential warming in Northern high latitudes. The simulations show interesting CO2‐induced changes in the seasonal excursion of the ITCZ and indicate a possible state dependence of climate sensitivity. The inclusion of an idealized continent modulates both the control climate and the response to increased CO2; for example, it reduces the northward ITCZ shift associated with warming and, in some models, climate sensitivity. In response to eccentricity‐driven seasonal insolation changes, seasonal changes in oceanic rainfall are best characterized as a meridional dipole, while seasonal continental rainfall changes tend to be symmetric about the equator. This survey illustrates TRACMIP's potential to engender a deeper understanding of global and regional climate and to address questions on past and future climate change.
Understanding the tropical cloud feedback from an analysis of the circulation and stability regimes simulated from an upgraded multiscale modeling framework
Authors: Xu Kuan‐Man , Cheng Anning
Published: November 2016

As revealed from studies using conventional general circulation models (GCMs), the thermodynamic contribution to the tropical cloud feedback dominates the dynamic contribution, but these models have difficulty in simulating the subsidence regimes in the tropics. In this study, we analyze the tropical cloud feedback from a 2 K sea surface temperature (SST) perturbation experiment performed with a multiscale modeling framework (MMF). The MMF explicitly represents cloud processes using 2‐D cloud‐resolving models with an advanced higher‐order turbulence closure in each atmospheric column of the host GCM. We sort the monthly mean cloud properties and cloud radiative effects according to circulation and stability regimes. We find that the regime‐sorted dynamic changes dominate the thermodynamic changes in terms of the absolute magnitude. The dynamic changes in the weak subsidence regimes exhibit strong negative cloud feedback due to increases in shallow cumulus and deep clouds while those in strongly convective and moderate‐to‐strong subsidence regimes have opposite signs, resulting in a small contribution to cloud feedback. On the other hand, the thermodynamic changes are large due to decreases in stratocumulus clouds in the moderate‐to‐strong subsidence regimes with small opposite changes in the weak subsidence and strongly convective regimes, resulting in a relatively large contribution to positive cloud feedback. The dynamic and thermodynamic changes contribute equally to positive cloud feedback and are relatively insensitive to stability in the moderate‐to‐strong subsidence regimes. But they are sensitive to stability changes from the SST increase in convective and weak subsidence regimes. These results have implications for interpreting cloud feedback mechanisms.
Expanded oxygen minimum zones during the late Paleocene‐early Eocene: Hints from multiproxy comparison and ocean modeling
Authors: Zhou X. , Thomas E. , Winguth A. M. E. , Ridgwell A. , Scher H. , Hoogakker B. A. A. , Rickaby R. E. M. , Lu Z.
Published: November 2016

Anthropogenic warming could well drive depletion of oceanic oxygen in the future. Important insight into the relationship between deoxygenation and warming can be gleaned from the geological record, but evidence is limited because few ocean oxygenation records are available for past greenhouse climate conditions. We use I/Ca in benthic foraminifera to reconstruct late Paleocene through early Eocene bottom and pore water redox conditions in the South Atlantic and Southern Indian Oceans and compare our results with those derived from Mn speciation and the Ce anomaly in fish teeth. We conclude that waters with lower oxygen concentrations were widespread at intermediate depths (1.5–2 km), whereas bottom waters were more oxygenated at the deepest site, in the Southeast Atlantic Ocean (>3 km). Epifaunal benthic foraminiferal I/Ca values were higher in the late Paleocene, especially at low‐oxygen sites, than at well‐oxygenated modern sites, indicating higher seawater total iodine concentrations in the late Paleocene than today. The proxy‐based bottom water oxygenation pattern agrees with the site‐to‐site O2 gradient as simulated in a comprehensive climate model (Community Climate System Model Version 3), but the simulated absolute dissolved O2 values are low (< ~35 µmol/kg), while higher O2 values (~60–100 µmol/kg) were obtained in an Earth system model (Grid ENabled Integrated Earth system model). Multiproxy data together with improvements in boundary conditions and model parameterization are necessary if the details of past oceanographic oxygenation are to be resolved.
Phase retrieval by constrained power inflation and signum flipping
Authors: Laganà A. R. , Morabito A. F. , Isernia T.
Published: November 2016

In this paper we consider the problem of retrieving a signal from the modulus of its Fourier transform (or other suitable transformations) and some additional information, which is also known as “Phase Retrieval” problem. The problem arises in many areas of applied Sciences such as optics, electron microscopy, antennas, and crystallography. In particular, we introduce a new approach, based on power inflation and tunneling, allowing an increased robustness with respect to the possible occurrence of false solutions. Preliminary results are presented for the simple yet relevant case of one‐dimensional arrays and noisy data.
Innovative framework to simulate the fate and transport of nonconservative constituents in urban combined sewer catchments
Authors: Morales V. M. , Quijano J. C. , Schmidt A. , Garcia M. H.
Published: November 2016

We have developed a probabilistic model to simulate the fate and transport of nonconservative constituents in urban watersheds. The approach implemented here extends previous studies that rely on the geomorphological instantaneous unit hydrograph concept to include nonconservative constituents. This is implemented with a factor χ that affects the transfer functions and therefore accounts for the loss (gain) of mass associated with the constituent as it travels through the watershed. Using this framework, we developed an analytical solution for the dynamics of dissolved oxygen (DO) and biochemical oxygen demand (BOD) in urban networks based on the Streeter and Phelps model. This model breaks down the catchment into a discreet number of possible flow paths through the system, requiring less data and implementation effort than well‐established deterministic models. Application of the model to one sewer catchment in the Chicago area with available BOD information proved its ability to predict the BOD concentration observed in the measurements. In addition, comparison of the model with a calibrated Storm Water Management Model (SWMM) of another sewer catchment from the Chicago area showed that the model predicted the BOD concentration as well as the widely accepted SWMM. The developed model proved to be a suitable alternative to simulate the fate and transport of constituents in urban catchments with limited and uncertain input data.
Comment on “Estimation of composite hydraulic resistance in ice‐covered alluvial streams” by Ghareh Aghaji Zare et al.
Authors: Beltaos Spyros
Published: November 2016

Inconsistencies between basic hydraulics and hypotheses advanced by the authors are identified. They are attributed primarily to weaknesses in the analysis of velocity measurements in the ice‐controlled flow layer and suggestions for improvement are offered.
Mapping soil water dynamics and a moving wetting front by spatiotemporal inversion of electromagnetic induction data
Authors: Huang J. , Monteiro Santos F. A. , Triantafilis J.
Published: November 2016

Characterization of the spatiotemporal distribution of soil volumetric water content (θ) is fundamental to agriculture, ecology, and earth science. Given the labor intensive and inefficient nature of determining θ, apparent electrical conductivity (ECa) measured by electromagnetic induction has been used as a proxy. A number of previous studies have employed inversion algorithms to convert ECa data to depth‐specific electrical conductivity (σ) which could then be correlated to soil θ and other soil properties. The purpose of this study was to develop a spatiotemporal inversion algorithm which accounts for the temporal continuity of ECa. The algorithm was applied to a case study where time‐lapse ECa was collected on a 350 m transect on seven different days on an alfalfa farm in the USA. Results showed that the approach was able to map the location of moving wetting front along the transect. Results also showed that the spatiotemporal inversion algorithm was more precise (RMSE = 0.0457 cm3/cm3) and less biased (ME = −0.0023 cm3/cm3) as compared with the nonspatiotemporal inversion approach (0.0483 cm3/cm3 and ME = −0.0030 cm3/cm3, respectively). In addition, the spatiotemporal inversion algorithm allows for a reduced set of ECa surveys to be used when non abrupt changes of soil water content occur with time. To apply this spatiotemporal inversion algorithm beyond low induction number condition, full solution of the EM induction phenomena can be studied in the future.
Icariin ameliorates IgA nephropathy by inhibition of nuclear factor kappa b/Nlrp3 pathway
Authors: Zhang Lei , Wang Xing‐Zhi , Li Yu‐Shu , Zhang Lei , Hao Li‐Rong
Published: November 2016

Immunoglobulin A nephropathy (IgAN) is the most frequent form of glomerulonephritis, which is characterized by glomerular proliferation and renal inflammation. Icariin is a flavonoid from the Chinese herb Epimedium, and its anti‐inflammatory effect has been reported. This study aimed to investigate the effects of icariin on the renal damage in IgAN rats and the mechanisms behind these effects. IgAN model was established in Sprague–Dawley rats by oral and intravenous immunization with bovine gamma‐globulin for 12 weeks, and rats were treated with icariin from 12 to 18 weeks. At the end of experimental period, kidneys, urine, and blood samples were collected for further analysis. Our results showed that icariin ameliorated the increase in the levels of proteinuria, serum creatinine, and urea nitrogen without severe side effects. IgAN rats exhibited significantly increased IgA deposition, mesangial matrix expansion, and glomerular fibrosis, while icariin treatment markedly attenuated these alterations. Moreover, treatment with icariin also dramatically blocked nuclear factor kappa b (NF‐κB) nuclear translocation and Nlrp3 inflammasome activation in IgAN rats, leading to reduced downstream proinflammatory cytokines production. Mechanistically, we found that icariin treatment inhibited IKKβ and IκBα phosphorylation and IκBα degradation in IgAN rats. Our data demonstrate that icariin ameliorates renal damage in IgAN rats via inhibition of NF‐κB‐mediated Nlrp3 inflammasome activation. These findings provide insight into an application of icariin for the treatment of IgAN disease, and represent a novel mechanism behind these effects.
Satellite Data
Authors: Shao Guofan
Published: November 2016

Earth observation satellites collect a variety of data relevant to a wide range of Earth resource topics, including Earth surface features and atmospheric conditions. Satellite data are collected, transmitted, stored, and analyzed in digital forms. Satellite data are characterized with spatial, spectral, radiometric, and temporal resolutions. A general indication of advancement of satellite data is that their resolutions are getting higher over time. Satellites can be used alone, to derive new data, and integrated with other geospatial data sources. One of the most common usages is to show satellite data in map format for human eyes to look at. While most of commercial satellite data can be purchased from data providers, many governmental satellite data can be downloaded without charge from US government web sites.
Survival Function
Authors: Rebora Paola , Valsecchi Maria Grazia
Published: November 2016

Survival data arise when we are interested in the time of occurrence of an event, and the survival function describes the cumulative probability of surviving beyond a given time point in a given group of individuals. Methods to estimate the survival function can be classified in nonparametric and model‐based methods and the main ones are described here. Among the nonparametric ones, the product limit, the life table, the Fleming–Harrington, and Bayesian methods are considered. Assumptions on right censoring and left truncation are discussed, with practical advices on how to present and read the survival curve. Aspects that are special to estimation of survival in the presence of time‐dependent variables and competing risks are mentioned. Among the model‐based methods, the use of estimators derived by the Cox model and parametric models is shown. Finally, relative survival and period analysis estimators are presented as useful tools in describing the survival experience in disease (cancer) registries, and survival estimators that account for special features in (nonrandom) designs are also briefly mentioned.
Optimal linear filtering for networked systems with communication constraints, fading measurements, and multiplicative noises
Authors: Liu Wei , Zhang Hongwei , Yu Kaijiang , Tan Xingguo
Published: November 2016

This paper is concerned with the filtering problem for discrete‐time networked systems with communication constraints, fading measurements, and multiplicative noises. The communication constraint is that, at each sampling instant, at most one of the various transmission nodes in the networked systems is permitted to access a shared communication channel, and then the received data are transmitted to a remote filter to perform the filtering task. The phenomenon of measurement fading appears in a random way when measurements are transmitted via the communication channel that undergoes slow fading. Using the innovation analysis approach and some results developed in this study, an optimal linear filter is proposed. The proposed optimal filter has a recursive structure and does not increase computation and storage load with time. Computer simulations are conducted to examine the performance of the proposed optimal filter. Copyright © 2016 John Wiley & Sons, Ltd.
Intimacy: Eragatory's Experiments in Materiality, Deep Texture and Mood
Authors: Bloch Isaie
Published: November 2016

Because of their textural and sensory qualities – even or uneven, smooth or rough, cold or warm, reflective or matt – particular materials tend to evoke particular moods. But this does not mean that their nature and structure cannot be played with in order to create surprising atmospheres. London‐based design practice Eragatory's ‘Intimacy’ series of interiors does just that, producing visual anomalies that distort the viewer's material understanding of space. Isaie Bloch, the firm's founder, describes how.
Figuring Mood: The Role of Stimmung in the Formal Approach of Heinrich Wölfflin and Alois Riegl
Authors: Saunders Andrew
Published: November 2016

Roughly translatable as ‘mood’ or ‘atmosphere’, Stimmung plays a key part in the late‐19th‐century writings of German art historians Wölfflin and Riegl. Andrew Saunders, Associate Professor of Architecture at the University of Pennsylvania School of Design, studies the origins of the concept, which links rational perceptions of harmony with notions of emotional response. He examines the two writers' contrasting views of Stimmung in relation to the Baroque, and highlights its little acknowledged role in the inception of formalism.
Moody Objects: Ore Fashion Stores and Blocks
Authors: del Campo Matias
Published: November 2016

The leading figures of Modernism instilled a fear of ornament as something unclean and even criminal. Guest‐Editor Matias del Campo calls for us to leave behind this phobia and engage anew with ornament for the purposes of generating mood and atmosphere. Here he describes two recent projects by SPAN, the Vienna‐based architectural practice he cofounded with Sandra Manninger, which explore alternatives to the usual aesthetic canons by addressing classic architectural problems in bold new ways.
Parrhesia‐stases (The Preamble)
Authors: Roche François , LacadÉe Camille
Published: November 2016

Operating between the obscene and methods of estrangement and displacement, parrhesia‐stases interrogates the agendas of aesthetics present in repulsiveness, condemnation and punishment. François Roche and Camille LacadÉe here present a body of work by their Bangkok‐based practice New‐Territories/M4, which speculates on the ramifications of architecture as a paradigm of disobedience. Deeply rooted in Michel Foucault's proposal for a re‐evaluation of an ethico‐political approach, the work investigates an alternative architectural position that utilises strategies of transfiguration to provoke pathological behaviours.
Excessive Resolution: From Digital Streamlining to Computational Complexity
Authors: Carpo Mario
Published: November 2016

Is the term ‘ornament’ set to become redundant in architecture? With the sinuous lines produced by CNC milling machines giving way to the ever more weirdly figural products of algorithmically controlled 3D printing, decoration is increasingly an integral part of form, rather than supplementary to it. Mario Carpo – Reyner Banham Professor of Architectural Theory and History at the Bartlett School of Architecture, University College London – investigates this voxellisation, and how it drives architecture beyond human comprehension.
Something Else, Something Raw: From ProtoHouse to Blokhut – The Aesthetics of Computational Assemblage
Authors: Retsin Gilles
Published: November 2016

London‐based architect Gilles Retsin is seeking out a new spatial experience. Enough of refined and carefully articulated surfaces and volumes. As demonstrated by these projects from his own practice and from the Softkill Design team – of which he is also a member – new digital techniques make it possible to devise environments that are infused with raw atmosphere. Here, the boundaries between interior and exterior, or between classic elements such as wall, floor and ceiling, are blurred to the point of nonexistence.
Differential Speed Rolling of Ni3Al‐Based Intermetallic Alloy − Electron Backscatter Diffraction and X‐Ray Diffraction Study on Structure and Texture Evolution
Authors: Polkowski Wojciech , Jóźwik Paweł , Łyszkowski Radosław , Bojar Zbigniew
Published: November 2016

Results of electron backscatter diffraction and X‐ray diffraction study on a microstructure, long range order, and texture evolution upon a differential speed rolling (DSR) of Zr and B doped Ni3Al‐based intermetallic alloy, are shown in the paper. The material is subjected to a 2‐pass cold rolling to the final thickness reduction of 50% under following upper to lower roll speed ratio R values: R = 1 (the equal speed rolling), R = 2, R = 3, and R = 4 (the DSR). Obtained results supported by literature data allows concluding that an introduction of the rolls speed asymmetry leads to a higher accumulated strain facilitating a strain induced disordering of L12 superlattice. This transformation is assisted by a changeover of a crystallographic texture type; indirectly indicating on a possible activation of mechanical twinning.
Piezotronic Effect on Electrical Characteristics of Bulk ZnO Varistors
Authors: Raidl Nadine , Hofstätter Michael , Supancic Peter
Published: November 2016

Electrical barriers at the grain boundaries of ZnO varistors are altered by mechanical stresses, which, therefore, play an important role regarding the functionality of the material. The stresses lead to the modification of electrical properties such as electrical conductivity and volume efficiency. An electrical 3D network model based on a realistic microstructure is presented. The model considers externally applied stress as well as micro stresses that evolve naturally during fabrication of materials with anisotropic thermal expansion coefficients. The predicted effects (i.e., increasing electrical conductivity and higher volume efficiency) due to compressive stresses are validated experimentally.
Piezoelectric Nylon‐11 Nanowire Arrays Grown by Template Wetting for Vibrational Energy Harvesting Applications
Authors: Datta Anuja , Choi Yeon Sik , Chalmers Evie , Ou Canlin , Kar‐Narayan Sohini
Published: November 2016

Piezoelectric polymers, capable of converting mechanical vibrations into electrical energy, are attractive for use in vibrational energy harvesting due to their flexibility, robustness, ease, and low cost of fabrication. In particular, piezoelectric polymers nanostructures have been found to exhibit higher crystallinity, higher piezoelectric coefficients, and “self‐poling,” as compared to films or bulk. The research in this area has been mainly dominated by polyvinylidene fluoride and its copolymers, which while promising have a limited temperature range of operation due to their low Curie and/or melting temperatures. Here, the authors report the fabrication and properties of vertically aligned and “self‐poled” piezoelectric Nylon‐11 nanowires with a melting temperature of ≈200 °C, grown by a facile and scalable capillary wetting technique. It is shown that a simple nanogenerator comprising as‐grown Nylon‐11 nanowires, embedded in an anodized aluminium oxide (AAO) template, can produce an open‐circuit voltage of 1 V and short‐circuit current of 100 nA, when subjected to small‐amplitude, low‐frequency vibrations. Importantly, the resulting nanogenerator is shown to exhibit excellent fatigue performance and high temperature stability. The work thus offers the possibility of exploiting a previously unexplored low‐cost piezoelectric polymer for nanowire‐based energy harvesting, particularly at temperatures well above room temperature.
Materials and Device Designs for an Epidermal UV Colorimetric Dosimeter with Near Field Communication Capabilities
Authors: Araki Hitoshi , Kim Jeonghyun , Zhang Shaoning , Banks Anthony , Crawford Kaitlyn E. , Sheng Xing , Gutruf Philipp , Shi Yunzhou , Pielak Rafal M. , Rogers John A.
Published: November 2016

Ultraviolet (UV) solar radiation is a leading cause of skin disease. Quantitative, continuous knowledge of exposure levels can enhance awareness and lead to improved health outcomes. Devices that offer this type of measurement capability in formats that can seamlessly integrate with the skin are therefore of interest. This paper introduces materials, device designs, and data acquisition methods for a skin‐like, or “epidermal,” system that combines colorimetric and electronic function for precise dosimetry in the UV‐A and UV‐B regions of the spectrum, and for determination of instantaneous UV exposure levels and skin temperature. The colorimetric chemistry uses (4‐phenoxyphenyl)diphenylsulfonium triflate (PPDPS‐TF) with crystal violet lactone (CVL) and Congo red for UV‐A and UV‐B operation, respectively, when integrated with suitable optical filters. Coatings of poly(ethylene‐vinylacetate) (PEVA) protect the functional materials from sunscreen and other contamination. Quantitative information follows from automated L*a*b* color space analysis of digital images of the devices to provide accurate measurements when calibrated against standard nonwearable sensors. Techniques of screen printing and lamination allow aesthetic designs and integration with epidermal near field communication platforms, respectively. The result is a set of attractive technologies for managing UV exposure at a personal level and on targeted regions of the body.
Chiroptical Resolution and Thermal Switching of Chirality in Conjugated Polymer Luminescence via Selective Reflection using a Double‐Layered Cell of Chiral Nematic Liquid Crystal
Authors: Yan Jialin , Ota Fuyuki , San Jose Benedict A. , Akagi Kazuo
Published: November 2016

An optically resolvable and thermally chiral‐switchable device for circularly polarized luminescence (CPL) is first constructed using a light‐emitting conjugated polymer film and a double‐layered chiral nematic liquid crystal (N*‐LC) cell. The double‐layered N*‐LC cell with opposite handedness at each layer is fabricated by adding each of two types of N*‐LCs into each of the cells, and the N*‐LCs consist of nematic LCs and chiral dopants with opposite chirality and different mole concentrations. The selective reflection band due to the N*‐LC is thermally shifted so that the band wavelength is close to the luminescence band of the racemic conjugated polymer, such as disubstituted polyacetylene (diPA), yielding CPL with opposite handedness and high dissymmetry factor values (|glum|) of 1.1–1.6 at low and high temperatures. The double‐layered N*‐LC cell bearing the temperature‐controlled selective reflection is useful for generating CPLs from racemic fluorescent materials and for allowing thermal chirality‐switching in CPLs, which present new possibilities for optoelectronic and photochemical applications.
Validating Metal‐Organic Framework Nanoparticles for Their Nanosafety in Diverse Biomedical Applications
Authors: Wuttke Stefan , Zimpel Andreas , Bein Thomas , Braig Simone , Stoiber Katharina , Vollmar Angelika , Müller Dominik , Haastert‐Talini Kirsten , Schaeske Jörn , Stiesch Meike , Zahn Gesa , Mohmeyer Alexander , Behrens Peter , Eickelberg Oliver , Bölükbas Deniz A. , Meiners Silke
Published: November 2016

Metal‐organic frameworks (MOFs) are promising platforms for the synthesis of nanoparticles for diverse medical applications. Their fundamental design principles allow for significant control of the framework architecture and pore chemistry, enabling directed functionalization for nanomedical applications. However, before applying novel nanomaterials to patients, it is imperative to understand their potential health risks. In this study, the nanosafety of different MOF nanoparticles is analyzed comprehensively for diverse medical applications. The authors first evaluate the effects of MOFs on human endothelial and mouse lung cells, which constitute a first line of defense upon systemic blood‐mediated and local lung‐specific applications of nanoparticles. Second, we validated these MOFs for multifunctional surface coatings of dental implants using human gingiva fibroblasts. Moreover, biocompatibility of MOFs is assessed for surface coating of nerve guidance tubes using human Schwann cells and rat dorsal root ganglion cultures. The main finding of this study is that the nanosafety and principal suitability of our MOF nanoparticles as novel agents for drug delivery and implant coatings strongly varies with the effector cell type. We conclude that it is therefore necessary to carefully evaluate the nanosafety of MOF nanomaterials with respect to their particular medical application and their interacting primary cell types, respectively.
Recent Progress on Stretchable Electronic Devices with Intrinsically Stretchable Components
Authors: Trung Tran Quang , Lee Nae‐Eung
Published: November 2016

Stretchable electronic devices with intrinsically stretchable components have significant inherent advantages, including simple fabrication processes, a high integrity of the stacked layers, and low cost in comparison with stretchable electronic devices based on non‐stretchable components. The research in this field has focused on developing new intrinsically stretchable components for conductors, semiconductors, and insulators. New methodologies and fabrication processes have been developed to fabricate stretchable devices with intrinsically stretchable components. The latest successful examples of stretchable conductors for applications in interconnections, electrodes, and piezoresistive devices are reviewed here. Stretchable conductors can be used for electrode or sensor applications depending on the electrical properties of the stretchable conductors under mechanical strain. A detailed overview of the recent progress in stretchable semiconductors, stretchable insulators, and other novel stretchable materials is also given, along with a discussion of the associated technological innovations and challenges. Stretchable electronic devices with intrinsically stretchable components such as field‐effect transistors (FETs), photodetectors, light‐emitting diodes (LEDs), electronic skins, and energy harvesters are also described and a new strategy for development of stretchable electronic devices is discussed. Conclusions and future prospects for the development of stretchable electronic devices with intrinsically stretchable components are discussed.
High‐Performance Bifunctional Metasurfaces in Transmission and Reflection Geometries
Authors: Cai Tong , Tang ShiWei , Wang GuangMing , Xu HeXiu , Sun ShuLin , He Qiong , Zhou Lei
Published: November 2016

Achieving multiple diversified functionalities in a single flat device is crucial for electromagnetic (EM) integration, but available efforts suffer the issues of device thickness, low efficiency, and restricted functionalities. Here, a general strategy to design high‐efficiency bifunctional devices based on metasurfaces composed by anisotropic meta‐atoms with polarization‐dependent phase responses is described. Based on the derived general criterions, two bifunctional metadevices, working in reflection and transmission modes, respectively, that can realize two distinct functionalities with very high efficiencies (≈90% in reflection geometry and ≈72% in transmission one) are designed and fabricated. Microwave experiments, including both far‐field and near‐field characterizations, are performed to demonstrate the predicted effects, which are in excellent agreement with numerical simulations. The findings in this study can motivate the realizations of high‐performance bifunctional metadevices in other frequency domains and with different functionalities, which are of crucial importance in EM integration.
Synthesis of Chiral Cyclopropyl Carbocyclic Purine Nucleosides via Asymmetric Intramolecular Cyclopropanations Catalyzed by a Chiral Ruthenium(II) Complex
Authors: Huang Ke‐Xin , Xie Ming‐Sheng , Zhao Guo‐Feng , Qu Gui‐Rong , Guo Hai‐Ming
Published: November 2016

The synthesis of chiral cyclopropyl carbocyclic purine nucleoside analogues via the highly enantioselective intramolecular cyclopropanation reactions has been reported. With a chiral ruthenium(II)‐phenyloxazoline complex as the catalyst, cyclopropyl carbocyclic purine nucleoside analogues containing three contiguous stereocenters were obtained with up to 99% yield and 99% ee. Furthermore, a chiral cyclopropyl carbocyclic adenosine nucleoside having anti‐BLV activity could be synthesized in a concise manner using this strategy.

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Palladium‐Catalyzed Selective Aryl Ring C–H Activation of N‐Acyl‐2‐aminobiaryls: Efficient Access to Multiaryl‐Substituted Naphthalenes
Authors: Annamalai Pratheepkumar , Chen Wu‐Yin , Raju Selvam , Hsu Kou‐Chi , Upadhyay Nitinkumar Satyadev , Cheng Chien‐Hong , Chuang Shih‐Ching
Published: November 2016

Palladium‐catalyzed cycloaromatization of N‐acyl‐2‐aminobiaryls, through a sequence of ortho C−H bond activation/alkyne insertion/meta C−H bond activation/alkyne insertion, was developed. An efficient synthesis of multiaryl‐substituted naphthalenes, N‐[2‐(5,6,7,8‐tetraarylnaphthalen‐1‐yl)aryl]acetamides, was demonstrated using molecular oxygen as the sole oxidant. Furthermore, through Buchwald's synthetic protocol, two compounds were converted into corresponding fluorescent carbazoles in 30–40% yield by intramolecular C−N bond formation.

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N,N‐Dimethylformamide as a Methylenating Reagent: Synthesis of Heterodiarylmethanes via Copper‐Catalyzed Coupling between Imidazo[1,2‐a]pyridines and Indoles/N,N‐Dimethylaniline
Authors: Mondal Susmita , Samanta Sadhanendu , Santra Sougata , Bagdi Avik K. , Hajra Alakananda
Published: November 2016

A new copper‐catalyzed, efficient method for the synthesis of heterodiarylmethanes through the coupling of imidazo[1,2‐a]pyridines with indoles employing N,N‐dimethylformamide as a methylenating reagent has been developed. A library of 3‐(1H‐indol‐3‐ylmethyl)‐imidazo[1,2‐a]pyridine derivatives has been synthesized under aerobic reaction conditions. This protocol is also applicable for the synthesis of (4‐imidazo[1,2‐a]pyridin‐3‐ylmethyl)(phenyl)dimethylamines. The method is highly selective for the hetero‐coupling.

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Copper‐Mediated Oxidative Radical Addition/Cyclization Cascade: Synthesis of Trifluoromethylated and Sulfonated Quinoline‐2,4(1H,3H)‐diones
Authors: Fu Hong , Wang Shi‐Sheng , Li Ya‐Min
Published: November 2016

A copper‐mediated oxidative radical addition/cyclization cascade of o‐cyanoarylacrylamides with sodium trifluoromethanesulfonate (Langlois’ reagent) has been achieved. The reaction proceeds through radical addition, cyclization, and imine hydrolysis, in which the cyclization was accomplished by an intramolecular addition of the carbon radical to the nitrile. This transformation exhibits a wide substrate scope and good functional group tolerance, thus providing a highly efficient and practical access to a variety of trifluoromethylated quinoline‐2,4(1H,3H)‐diones. Furthermore, using other sulfinic acid sodium salts as sulfonylating agents, sulfonated quinolinediones were also obtained through a similar radical cascade.

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