bluuebunny/crossref_metadata_2025 huggingface dataset:
WRF-Chem simulation of aerosol seasonal variability in the San Joaquin Valley
Authors: Wu Longtao , Su Hui , Kalashnikova Olga V. , Jiang Jonathan H. , Zhao Chun , Garay Michael J. , Campbell James R. , Yu Nanpeng
Published: June 2017

Abstract. WRF-Chem simulations of aerosol seasonal variability in the San Joaquin Valley (SJV), California, are evaluated by satellite and in situ observations. Results show that the WRF-Chem model successfully captures the distribution and magnitude of and variation in SJV aerosols during the cold season. However, aerosols are not well represented in the warm season. Aerosol simulations in urban areas during the cold season are sensitive to model horizontal resolution, with better simulations at 4 km resolution than at 20 km resolution, mainly due to inhomogeneous distribution of anthropogenic emissions and precipitation that is represented better in the 4 km simulation. In rural areas, the model sensitivity to grid size is rather small. Our observational analysis reveals that dust is a primary contributor to aerosols in the SJV, especially during the warm season. Aerosol simulations in the warm season are sensitive to the parameterization of dust emission in WRF-Chem. The GOCART (Goddard Global Ozone Chemistry Aerosol Radiation and Transport) dust scheme produces very little dust in the SJV, while the DUSTRAN (DUST TRANsport model) scheme overestimates dust emission. Vertical mixing of aerosols is not adequately represented in the model based on CALIPSO (Cloud-Aerosol Lidar and Infrared pathfinder Satellite Observation) aerosol extinction profiles. Improved representation of dust emission and vertical mixing in the boundary layer is needed for better simulations of aerosols during the warm season in the SJV.
Satoyama Landscapes and Their Change in A River Basin context: Lessons for Sustainability
Authors: Chakraborty Shamik , Chakraborty Abhik
Published: June 2017

'Satoyama' denotes a mosaic of different landscape-types that has sustained agrarian societies for millennia in Japan. These landscapes have undergone degradation during the past few decades. While satoyama is a consistently referred term in landscape management in Japan, little attention is given to how such landscapes undergo change in large spatial units such as river basins. This study, based on documents and interviews, reviews how watershed level changes affect the functioning of such socioecological systems in the Kuma River Basin in Kyushu. Watershed properties of the Kuma River Basin changed during pre-modern and modern times and each phase left a lasting legacy on the landscape. The article analyzes how ecological connectivity became fragmented by identifying changes in ecosystem services, and concludes that while socio-ecological landscapes have a long history of human use; the human component cannot outgrow the fundamental biophysical processes that maintain ecosystem services and system resilience; these systems can undergo swift and irreversible degradation when ecological connectivity is fragmented. The main lesson for sustainable development is that consideration of historical changes in land use is vital for understanding the connectivity of different components in satoyama landscapes; this insight is important not only for rivers but also for the wider landscapes they connect and the associated integrity.
Meandering Process and Migration Architecture: Based on the Nowitna River
Authors: Chen Le , Lin Zhipeng , Yin Taiju , Shan Jingfu , Sun Qianjun , Wang Fei
Published: June 2017

The meandering process has always been the topic through years and still remains a lot of unsolved mysteries. One of the most important focus is the migration architectures and models that the meandering channels follow. This article chooses the Nowitna River as the study object of the typical meandering river with high migratory processes. Though the high-resolution historical satellite images by the techniques of Google Earth and ACME Mapper, 50 meanders in the river is studied and 6 of which are chosen for meticulous characterization. During the process, the planform structure of meandering channel is re-examined and 29 kinds of architecture elements are systematically established. More importantly, in order to make a fine quantitative characterization of the channel structure of meandering river, 5 kinds of characterization parameters are proposed, extraordinarily, the parameters of the difference of along-current deflection angle, a difference of counter-current deflection angle, and expansion coefficient, these three are firstly brought forward and applied introduction. In addition, the conception of sinuosity index and curvature are also different from the original definition. Though these architectures elements the meandering process and migration structure of the Nowitna River is demonstrated. 6 kinds of planform migration structures is revealed with the quantitative characterization of characterization parameters and 9 species of meandering channel migration patterns are concluded and discussed.
Chromatographic Methods for Coffee Analysis: A Review
Authors: Yashin Alexander , Yashin Yakov , Xia Xiaoyan , Nemzer Boris
Published: June 2017

Coffee has been one of the most commercialized food products and most widely researched beverage in the world for decades. It is considered a functional food, primarily due to its high content of compounds that exert antioxidant and other beneficial biological properties. This review summarized the data from analysis of coffee components, both volatile constituents and non-volatile high-molecular weight compounds performed by various chromatographic methods. A list of compounds identified by gas chromatography with mass spectrometry which define the aroma of coffee is provided. Publications on the measurement of methylxanthines (caffeine, theobromine, and theophylline), chlorogenic acids, diterpenes, sugars, amino acids, gamma-aminobutyric acid, dibasic acids, anions, and other compounds by HPLC and UHPLC-MS are reviewed. An overview of publications on the determination of organic contamination in coffee (PAHs, acrylamides, mycotoxins, etc.) and ways to reduce contamination through production technology and brewing methods are presented. Finally, an overview of the literature on authentication assessment for different grades of coffee grown in different regions is provided.
Management of Snap Bean Insect Pests and Diseases by Use of Antagonistic Fungi and Plant Extracts
Authors: Muthomi James , Fulano A. M. , Wagacha J. M. , Mwang’ombe A. W.
Published: June 2017

Use of synthetic pesticides reduces the competitiveness of Kenyan snap bean pods due to stringent regulations by importers as a result of presence of chemical residues. This study was conducted to determine the effectiveness of local biopesticides in managing insect pests and diseases of snap beans. Field experiments were set up in farmer's field where Trichoderma spp. and Paecilomyce spp. and plant extracts from turmeric, garlic, ginger and lemon were applied weekly as foliar sprays. Plant extracts reduced the population of whiteflies and thrips by up to 58% and 41% while antagonistic fungi had a corresponding 30% and 18% reduction, respectively. Trichoderma spp. reduced severity of angular leaf spot (37.5%), rust (67%) and anthracnose (20.7%). Plant extracts and antagonistic fungi increased marketable pod yield by 25.6% and 17.3%, respectively. Results demonstrated that local environments are potential sources of biopesticides that can be exploited for integrated management of pests and diseases.
Graphene Nanolayers as a New Method for Bacterial Biofilm Prevention: Preliminary Results
Authors: Dybowska-Sarapuk Łucja , Kotela Andrzej , Krzemiński Jakub , Wróblewska Marta , Marchel Halina , Romaniec Magdalena , Łęgosz Paweł , Jakubowska Małgorzata
Published: June 2017

Biofilms are microbial communities of surface-attached cells embedded in a self-produced extracellular matrix. They have been found to play a role in a wide variety of infections, including catheter-related urinary tract and bloodstream infections, and, therefore remain a significant source of morbidity and mortality among the world's population. Recently, much attention has been devoted to the prevention of biofilm formation on implant surfaces. Nanomaterials such as graphene, characterized by antibacterial activity and low toxicity to human cells, are promising candidates for biomedical applications. This study investigates the antibacterial efficiency of graphene and specially produced graphene decorated with silver nanoparticles, obtained by one of the methods of printed electronics (spray-coating system). These methods are not only economical, but also enable the printing of layers of various thicknesses on different types of materials, including flexible and nonplanar substrates. The aim of the study was to reveal the ability of graphene and graphene-nanosilver layers to prevent the formation of Staphylococcus epidermidis biofilm on the surface of a Foley catheter.
The Method of Coating Fe3O4 with Carbon Nanoparticles to Modify Biological Properties of Oxide Measured in Vitro
Authors: Niemiec Tomasz , Dudek Mariusz , Dziekan Natalia , Jaworski Sławomir , Przewozik Aleksandra , Soszka Emilia , Koperkiewicz Anna , Koczoń Piotr
Published: June 2017

The coating of nanoparticles on materials for medical application [e.g., the coating of Fe3O4 nanopowder (IONP) with a carbon nanolayer] serves to protect and modify the selected biological, physical, and chemical properties of the coated material. Increases in chemical stability, changes in biocompatibility, and a modified surface structure are examples of the effects caused by the formation of carbon coatings. In the current study, Fe3O4 nanoparticles were coated with a carbon nanolayer (IONP@C) in a plasmochemical reactor (using radio-frequency plasma-enhanced chemical vapor deposition methods) under various experimental conditions. Based on data from X-ray diffraction, Raman, and IR spectroscopy, the best processing parameters were determined in order to produce a carbon coating that would not change the structure of the IONP. The materials with the best cover, i.e., a uniform carbon nanolayer, were used in cytotoxic tests to investigate their biological properties using the human HepG2 hepatocarcinoma cell line and chicken embryo red blood cells as an in vitro model. The obtained results proved the low cytotoxicity of Fe3O4 micropowder and IONP in contrast to IONP@C, which reduced cell viability, increased hemolysis, and generally was more toxic than bare Fe3O4.
Micro Thin-Layer Chromatography Fingerprints of Selected Basil Species and Their Chemometric Analysis
Authors: Hawrył Mirosław A , Świeboda Ryszard , Hawrył Anna , Niemiec Małgorzata , Waksmundzka-Hajnos Monika
Published: June 2017

The dried aerial parts of 12 plants of Ocimum spp. were extracted with the Soxhlet apparatus using dichloromethane and methanol as solvents. A micro-TLC system with silica and a normal-phase solvent system (propan-2-ol–n-heptane–formic acid) was used for the chemometric analysis of 12 selected basil methanolic extracts. Some indices of similarity (Pearson's correlation coefficient, determination coefficient, congruence coefficient, and Euclidean, Manhattan (city-block), Chebyshev, and Hausdorff distances) were calculated on the basis of thin-layer chromatograms using ImageJ software. Principal component analysis was also performed. The method allowed the comparison of the analyzed extracts and confirmed the identities of two selected unknown plants.
The Thin-Layer Microchromatography (μTLC) and TLC–FID Technique as a New Methodology in the Study of Lubricating Oils
Authors: Nowak Paulina , Kosińska Judyta , Glinka Marta , Kamiński Marian
Published: June 2017

This paper concerns the possibility of using TLC coupled with a flame ionization detector (FID) and micro-TLC (μTLC) as precursors for microfluidized devices of analytical techniques to identify and determine the presence and content of the petroleum/vegetable oil base in the lubricating oils applied in cutting devices (chainsaws). This research is related to the problem of ensuring, in compliance with the requirements of environmental protection, a sufficient level of biodegradability of lubricating oils emitted to the environment during operation of equipment lubricated with these oils. Such oils include those mainly used in cutting devices and emitted in the form of a mist into the environment during the operation of those devices. When oil components are eco-toxic, contamination of the environment occurs. New methodologies for the identification and determination of the petroleum oil base, which is very difficult to biodegrade, as well as the easily biodegradable ingredients of vegetable origin in the lubricating oils, are presented. The described procedures indicate in an indisputable way whether the oil contains the oil base originating from crude oil and whether it contains adequate enriching additives. The procedures also allow the assessment of the content of particular groups of constituents (μTLC) or the determination of the group composition (TLC–FID).
Quantum Dots as Components of Electrochemical Sensing Platforms for the Detection of Environmental and Food Pollutants: a Review
Authors: Pedrero María , Campuzano Susana , Pingarrón José M
Published: June 2017

The determination of organic and inorganic environmental and food pollutants is a key matter of concern in analytical chemistry due to their effects as a serious threat to human health. Focusing on this issue, several methodologies involving the use of nanostructured electrochemical platforms have been recently reported in the literature. Among these methods, those employing the use of quantum dots (QDs) stand out because of features such as signal amplification, good reproducibility and selectivity, and the possibility for multiplexed detection, and because they preserve the outstanding characteristics of electrochemical methodologies with respect to simplicity, ease-of-use, and cost-effective instrumentation. This review describes recent electrochemical strategies, in which design QDs play a key role, for the determination of pollutants in food and environmental samples. The particular role of QDs in the reported methodologies, their preparation, and the electrochemical platform design, as well as the advantages that QDs provide in the analysis of target analytes, are critically discussed.
Advances in the Analysis of Water and Wastewater Samples Using Various Sensing Protocols and Microfluidic Devices Based on PAD and μTAS Systems
Authors: Piaskowski Krzysztof , Świderska-Dąbrowska Renata , Kaleniecka Aleksandra , Zarzycki Paweł K
Published: June 2017

The main goal of this review is to summarize practical approaches concerning the application of microfluidic systems for the analysis of various biomarkers and pollutants, as well as microbes, in water and wastewater matrixes. This problem involves multidisciplinary expertise combining research knowledge from various areas, including wet chemistry, biochemistry, physical chemistry, molecular biology, genetics, signal processing, microelectronics material science, and separation science. It has been documented that fairly primitive but fast and inexpensive screening methods involving paper-based analytical devices (PADs) and micro total analytical systems (μTAS) can be considered as serious alternatives to their more advanced counterparts such as GC, HPLC, and capillary electrophoresis coupled to various sophisticated detectors (e.g., multiwavelength spectrophotometers such as UV-Vis/DAD and mass spectrometers). The main advantage of PAD- and μTAS-driven technology is that such sensing devices may work under on-site and real-time conditions and measure a number of physical parameters and chemical factors simultaneously. Moreover, hybrid miniaturized analytical systems may combine sensing and data acquisition modules with common mobile phones and electronic devices working with global positioning systems and communicating through the Internet.
Mechanosensory neurons control the timing of spinal microcircuit selection during locomotion
Authors: Knafo Steven , Fidelin Kevin , Prendergast Andrew , Tseng Po-En Brian , Parrin Alexandre , Dickey Charles , Böhm Urs Lucas , Figueiredo Sophie Nunes , Thouvenin Olivier , Pascal-Moussellard Hugues , Wyart Claire
Published: June 2017

Despite numerous physiological studies about reflexes in the spinal cord, the contribution of mechanosensory feedback to active locomotion and the nature of underlying spinal circuits remains elusive. Here we investigate how mechanosensory feedback shapes active locomotion in a genetic model organism exhibiting simple locomotion—the zebrafish larva. We show that mechanosensory feedback enhances the recruitment of motor pools during active locomotion. Furthermore, we demonstrate that inputs from mechanosensory neurons increase locomotor speed by prolonging fast swimming at the expense of slow swimming during stereotyped acoustic escape responses. This effect could be mediated by distinct mechanosensory neurons. In the spinal cord, we show that connections compatible with monosynaptic inputs from mechanosensory Rohon-Beard neurons onto ipsilateral V2a interneurons selectively recruited at high speed can contribute to the observed enhancement of speed. Altogether, our study reveals the basic principles and a circuit diagram enabling speed modulation by mechanosensory feedback in the vertebrate spinal cord.
The genome and phenome of the green alga Chloroidium sp. UTEX 3007 reveal adaptive traits for desert acclimatization
Authors: Nelson David R , Khraiwesh Basel , Fu Weiqi , Alseekh Saleh , Jaiswal Ashish , Chaiboonchoe Amphun , Hazzouri Khaled M , O’Connor Matthew J , Butterfoss Glenn L , Drou Nizar , Rowe Jillian D , Harb Jamil , Fernie Alisdair R , Gunsalus Kristin C , Salehi-Ashtiani Kourosh
Published: June 2017

To investigate the phenomic and genomic traits that allow green algae to survive in deserts, we characterized a ubiquitous species, Chloroidium sp. UTEX 3007, which we isolated from multiple locations in the United Arab Emirates (UAE). Metabolomic analyses of Chloroidium sp. UTEX 3007 indicated that the alga accumulates a broad range of carbon sources, including several desiccation tolerance-promoting sugars and unusually large stores of palmitate. Growth assays revealed capacities to grow in salinities from zero to 60 g/L and to grow heterotrophically on >40 distinct carbon sources. Assembly and annotation of genomic reads yielded a 52.5 Mbp genome with 8153 functionally annotated genes. Comparison with other sequenced green algae revealed unique protein families involved in osmotic stress tolerance and saccharide metabolism that support phenomic studies. Our results reveal the robust and flexible biology utilized by a green alga to successfully inhabit a desert coastline.
A Stylistic Analysis of Linguistic Patterns in Chichamanda Ngozi Adichie’s Purple Hibiscus
Authors: Sholakhuddin Al Fajri Muchamad
Published: June 2017

This study aims to carry out a detailed and systematic stylistic analysis of linguistic patterns in Purple Hibiscus Novel by Chichamanda Ngozi Adichie. It particularly analyses a specific extract of the novel in terms of narration and point of view, conversational analysis, speech and thought presentations and mind style, and how these linguistic devices and patterns are employed by the author to shape characters’ personalities and relationships between them in the reader’s mind. The result appears to suggest that the author successfully represents the protagonist, Kambili as an obedient and a salient daughter who respects deeply his father, while her father, Eugene, is constructed as a strict father and religious who imposes an absolute control on his daughter.
Reading Difference in Identity: Lacanian Reasoning in Paul Auster’s Invisible
Authors: Momeni Javad , Jalali Farahani Bahare
Published: June 2017

The prevailing motifs of Auster’s literary oeuvre such as chance, contingent events, writing and the binary opposition of reader and author are also noticeable in Paul Auster’s Invisible; however, in this article, we examine the novel in terms of the characters’ psychological attempts to form their different identifications within Lacanian theoretical framework. Born acts as both reified big Other and object petit a for Walker, while Walker, in his different encounters with Born, experiences disparate Zizekian parallax views. Holding such views, Walker stands in the middle of the various courses of subjectivities, thereby undergoing a complicated interwoven subjectivity. Furthermore, Born’s encounters with the Real, epitomized in Born, place him in the two concurrent positions of subjectivities both in the Imaginary and the Symbolic order. As a result, his constant Symbolic identifications with signifying traits of Born’s bring him nothing but an aporia of logical perplexities. Last but not the least, we emphasize that the fluctuation between lost object and the loss itself, as an object, plums the depth of the anxieties embedded in such interwoven subjectivity.
Critical Zone services as environmental assessment criteria in intensively managed landscapes
Authors: Richardson Meredith , Kumar Praveen
Published: June 2017

The Critical Zone (CZ) includes the biophysical processes occurring from the top of the vegetation canopy to the weathering zone below the groundwater table. CZ services provide a measure for the goods and benefits derived from CZ processes. In intensively managed landscapes, cropland is altered through anthropogenic energy inputs to derive more productivity, as agricultural products, than would be possible under natural conditions. However, the actual costs of alterations to CZ functions within landscape profiles are unknown. Through comparisons of corn feed and corn‐based ethanol, we show that valuation of these CZ services in monetary terms provides a more concrete tool for characterizing seemingly abstract environmental damages from agricultural production systems. Multiple models are combined to simulate the movement of nutrients throughout the soil system, enabling the measurement of agricultural anthropogenic impacts to the CZ's regulating services. Results indicate water quality and atmospheric stabilizing services, measured by soil carbon storage, carbon respiration, and nitrate leaching, among others, can cost more than double that of emissions estimated in previous studies. Energy efficiency in addition to environmental impact is assessed to demonstrate how the inclusion of CZ services is necessary in accounting for the entire life cycle of agricultural production systems. These results conclude that feed production systems are more energy efficient and less environmentally costly than corn‐based ethanol.
Occurrence rate of whistler waves in the magnetotail reconnection region
Authors: Huang S. Y. , Yuan Z. G. , Sahraoui F. , Fu H. S. , Pang Y. , Zhou M. , Fujimoto K. , Deng X. H. , Retinò A. , Wang D. D. , Yu X. D. , Li H. M.
Published: June 2017

It has long been suggested that whistler waves play an active role during magnetic reconnection. However, all previous observations were based on case studies and could not give a detailed picture as to where the whistler waves occur in the reconnection region. In this paper, a statistical study by using the Cluster data is performed to investigate the spatial distribution and the occurrence rate of whistler waves in the magnetotail reconnection region. It is found that the occurrence rate of the whistler waves is large in the separatrix region (|Bx/B0| > 0.4) and in the pileup region (|Bx/B0| < 0.2, |θ| > 45°, where θ = arctan(Bz/Bx)), but is very small in the vicinity of the X‐line. These statistical results are well consistent with recent kinetic simulations and with previous observational case studies.
Black Sea thermohaline properties: Long‐term trends and variations
Authors: Miladinova S. , Stips A. , Garcia‐Gorriz E. , Macias Moy D.
Published: June 2017

The current knowledge about spatial and temporal dynamics of the Black Sea's thermohaline structure is incomplete because of missing data and sparse distribution of existing measurements in space and time. This study presents 56 year continuous simulations of the Black Sea's hydrodynamics using the 3D General Estuarine Transport Model (GETM), without incorporating any relaxation toward climatological or observational data fields. This property of the model allows us to estimate independent temporal trends, in addition to resolving the spatial structure. The simulations suggest that the intermediate layer temperature is characterized by a weak positive trend (warming), whereas the surface temperature does not show a clear linear trend. Different salinity trends have been established at the surface (negative), upper (weaker negative) and main halocline (positive). Three distinct dynamic periods are identified (1960–1970, 1970–1995, 1995–2015), which exhibit pronounced changes in the Black Sea's thermohaline properties and basin circulation. Strengthening of the main cyclonic circulation, accompanied by intensification of the mesoscale anticyclonic eddy formation is found. Both events strongly affect the sea surface salinity but contribute in opposing directions. Specifically, strong composite large‐scale circulation leads to an increase in sea surface salinity, while enhanced formation of mesoscale anticyclones decreases it. Salinity evolution with time is thus the result of the competition of these two opposing yet interdependent processes.
Congo Basin precipitation: Assessing seasonality, regional interactions, and sources of moisture
Authors: Dyer Ellen L. E. , Jones Dylan B. A. , Nusbaumer Jesse , Li Harry , Collins Owen , Vettoretti Guido , Noone David
Published: June 2017

Precipitation in the Congo Basin was examined using a version of the National Center for Atmospheric Research Community Earth System Model (CESM) with water tagging capability. Using regionally defined water tracers, or tags, the moisture contribution from different source regions to Congo Basin precipitation was investigated. We found that the Indian Ocean and evaporation from the Congo Basin were the dominant moisture sources and that the Atlantic Ocean was a comparatively small source of moisture. In both rainy seasons the southwestern Indian Ocean contributed about 21% of the moisture, while the recycling ratio for moisture from the Congo Basin was about 25%. Near the surface, a great deal of moisture is transported from the Atlantic into the Congo Basin, but much of this moisture is recirculated back over the Atlantic in the lower troposphere. Although the southwestern Indian Ocean is a major source of Indian Ocean moisture, it is not associated with the bulk of the variability in precipitation over the Congo Basin. In wet years, more of the precipitation in the Congo Basin is derived from Indian Ocean moisture, but the spatial distribution of the dominant sources is shifted, reflecting changes in the midtropospheric circulation over the Indian Ocean. During wet years there is increased transport of moisture from the equatorial and eastern Indian Ocean. Our results suggest that reliably capturing the linkages between the large‐scale circulation patterns over the Indian Ocean and the local circulation over the Congo Basin is critical for future projections of Congo Basin precipitation.
Propagation and arrest of dikes under topography: Models applied to the 2014 Bardarbunga (Iceland) rifting event
Authors: Urbani S. , Acocella V. , Rivalta E. , Corbi F.
Published: June 2017

Dikes along rift zones propagate laterally downslope for tens of kilometers, often becoming arrested before topographic reliefs. We use analogue and numerical models to test the conditions controlling the lateral propagation and arrest of dikes, exploring the presence of a slope in connection with buoyancy and rigidity layering. A gentle downslope assists lateral propagation when combined with an effective barrier to magma ascent, e.g., gelatin stiffness contrasts, while antibuoyancy alone may be insufficient to prevent upward propagation. We also observe that experimental dikes become arrested when reaching a plain before opposite reliefs. Our numerical models show that below the plain the stress field induced by topography hinders further dike propagation. We suggest that lateral dike propagation requires an efficient barrier (rigidity) to upward propagation, assisting antibuoyancy, and a lateral pressure gradient perpendicular to the least compressive stress axis, while dike arrest may be induced by external reliefs.
Unprecedented springtime retreat of Antarctic sea ice in 2016
Authors: Turner John , Phillips Tony , Marshall Gareth J. , Hosking J. Scott , Pope James O. , Bracegirdle Thomas J. , Deb Pranab
Published: June 2017

During austral spring 2016 Antarctic sea ice extent (SIE) decreased at a record rate of 75 × 103 km2 d−1, which was 46% faster than the mean rate and 18% faster than in any previous spring season during the satellite era. The decrease of sea ice area was also exceptional and 28% greater than the mean. Anomalous negative retreat occurred in all sectors of the Antarctic but was greatest in the Weddell and Ross Seas. Record negative SIE anomalies for the day of year were recorded from 3 November 2016 to 9 April 2017. Rapid ice retreat in the Weddell Sea took place in strong northerly flow after an early maximum ice extent in late August. Rapid ice retreat occurred in November in the Ross Sea when surface pressure was at a record high level, with the Southern Annular Mode at its most negative for that month since 1968.
Quantifying black carbon deposition over the Greenland ice sheet from forest fires in Canada
Authors: Thomas J. L. , Polashenski C. M. , Soja A. J. , Marelle L. , Casey K. A. , Choi H. D. , Raut J.‐C. , Wiedinmyer C. , Emmons L. K. , Fast J. D. , Pelon J. , Law K. S. , Flanner M. G. , Dibb J. E.
Published: June 2017

Black carbon (BC) concentrations observed in 22 snowpits sampled in the northwest sector of the Greenland ice sheet in April 2014 have allowed us to identify a strong and widespread BC aerosol deposition event, which was dated to have accumulated in the pits from two snow storms between 27 July and 2 August 2013. This event comprises a significant portion (57% on average across all pits) of total BC deposition over 10 months (July 2013 to April 2014). Here we link this deposition event to forest fires burning in Canada during summer 2013 using modeling and remote sensing tools. Aerosols were detected by both the Cloud‐Aerosol Lidar with Orthogonal Polarization (on board CALIPSO) and Moderate Resolution Imaging Spectroradiometer (Aqua) instruments during transport between Canada and Greenland. We use high‐resolution regional chemical transport modeling (WRF‐Chem) combined with high‐resolution fire emissions (FINNv1.5) to study aerosol emissions, transport, and deposition during this event. The model captures the timing of the BC deposition event and shows that fires in Canada were the main source of deposited BC. However, the model underpredicts BC deposition compared to measurements at all sites by a factor of 2–100. Underprediction of modeled BC deposition originates from uncertainties in fire emissions and model treatment of wet removal of aerosols. Improvements in model descriptions of precipitation scavenging and emissions from wildfires are needed to correctly predict deposition, which is critical for determining the climate impacts of aerosols that originate from fires.
Solute mixing regulates heterogeneity of mineral precipitation in porous media
Authors: Cil Mehmet B. , Xie Minwei , Packman Aaron I. , Buscarnera Giuseppe
Published: June 2017

Synchrotron X‐ray microtomography was used to track the spatiotemporal evolution of mineral precipitation and the consequent alteration of the pore structure. Column experiments were conducted by injecting CaCl2 and NaHCO3 solutions into granular porous media either as a premixed supersaturated solution (external mixing) or as separate solutions that mixed within the specimen (internal mixing). The two mixing modes produced distinct mineral growth patterns. While internal mixing promoted transverse heterogeneity with precipitation at the mixing zone, external mixing favored relatively homogeneous precipitation along the flow direction. The impact of precipitation on pore water flow and permeability was assessed via 3‐D flow simulations, which indicated anisotropic permeability evolution for both mixing modes. Under both mixing modes, precipitation decreased the median pore size and increased the skewness of the pore size distribution. Such similar pore‐scale evolution patterns suggest that the clogging of individual pores depends primarily on local supersaturation state and pore geometry.
Statistical study of particle acceleration in the core of foreshock transients
Authors: Liu Terry Z. , Angelopoulos Vassilis , Hietala Heli , Wilson III Lynn B.
Published: June 2017

Several types of foreshock transients upstream of Earth's bow shock possessing a tenuous, hot core have been observed and simulated. Because of the low dynamic pressure in their cores, these phenomena can significantly disturb the bow shock and the magnetosphere‐ionosphere system. Recent observations have also demonstrated that foreshock transients can accelerate particles which, when transported earthward, can affect space weather. Understanding the potential of foreshock transients to accelerate particles can help us understand shock acceleration at Earth and at other planetary and astrophysical systems. To further investigate foreshock transients' potential for acceleration, we conduct a statistical study of ion and electron energization in the core of foreshock transients. We find that electron energies typically increase there, evidently due to an internal acceleration process, whereas, as expected, ion energies most often decrease to support transient formation and expansion. Nevertheless, ion energy enhancements can be seen in some events suggesting an internal ion acceleration process as well. Formation conditions of foreshock transients are related to weak solar wind magnetic field strength and fast solar wind speed. Ion and electron energization are also positively correlated with solar wind speed.
Efficiency of coseismic ionospheric perturbations in identifying crustal deformation pattern: Case study based on Mw 7.3 May Nepal 2015 earthquake
Authors: Bagiya Mala S. , Sunil A. S. , Sunil P. S. , Sreejith K. M. , Rolland Lucie , Ramesh D. S.
Published: June 2017

The amplitude asymmetry and initial polarity of seismic induced ionospheric perturbations around the epicenter are considered to be important in providing information about the rupture propagation and related vertical surface deformation. To comprehend this, we study ionospheric perturbations related to the 12 May 2015, Mw 7.3 Nepal earthquake. We model the coseismic slip associated with the event using the interferometric synthetic aperture radar derived surface deformation data. The ionospheric perturbations associated with the obtained surface deformation are explained in terms of rupture propagation, favorable geomagnetic field‐wave coupling, and satellite geometry effects. We discuss the effects of phase cancelation on the perturbation evolution for various receiver satellite line‐of‐sight configurations invoking an elementary version of satellite geometry factor. The present study thus elucidates further the role of nontectonic forcing mechanisms while identifying ground source pattern using the associated ionospheric perturbations.
Electron temperature anisotropy associated to field‐aligned currents in the Earth's magnetosphere inferred from Rosetta MIP‐RPC observations during 2009 flyby
Authors: Béghin C. , Hamelin M. , Lebreton J. P. , Vallieres X. , Moré J. , Henri P.
Published: June 2017

A new approach is proposed for data interpretation of the Mutual Impedance Probe (MIP) instrument from the Rosetta Plasma Consortium (RPC) during the 2009 Earth's flyby gravity assist through the magnetosphere, from dusk to dawn regions. The spacecraft trajectory of ±8 RE (Earth's radius) was crossing several structures of field‐aligned currents (FACs) and radiations belts on both legs of the closest approach (CA, 2.450 km altitude). As routinely revealed by several pioneering space missions, natural and forced electrostatic wave emissions called Fqs were observed over ±3 RE at around CA using a dedicated mode of the MIP instrument. These emissions are lying between consecutive harmonics of the electron‐cyclotron frequency, and their wavelength is perpendicular to the magnetic field lines. Provided that the Fq's wavelengths projected along the MIP antenna might be estimated, it is shown that the local value of the Larmor radius can be deduced; hence, the electron temperature component perpendicular to the magnetic field is subsequently derived. On the other hand, during the time of Fq's observations, the presence of VLF hiss emissions usually observed in these regions gives us the possibility to determine the electron temperature anisotropy associated to the electrostatic electron anisotropy instability according to the theoretical model proposed by Gary and Cairns (JGR, vol. 104, 1999). Significant dynamic constraints revealed by crossing successive series of FACs tubes are shown being controlled by this anisotropy, and the fact that the magnetic pressure is significantly larger than the thermal pressure suggests that the FACs lobes are nonforce free.
Midnight flash model of energetic neutral atom periodicities at Saturn
Authors: Carbary J. F. , Mitchell D. G.
Published: June 2017

The Ion Neutral Camera on the Cassini spacecraft made images of energetic H atoms (25–55 keV) over a 3 day span in 2017. The images were projected onto the equatorial plane of Saturn, and a keogram was made by interpolating the projections in local time at 9 RS (1 RS = 60268 km). The keogram intensities show strong periodicities near the 10.79 h period of Saturn's energetic particles and exhibit a slope commensurate with corotation at that period. These periodic fluxes intensify near midnight but are weaker near noon. A “midnight flash” model can explain this behavior in terms of a searchlight rotating at 10.79 h that intensifies in the midnight sector. The model can also describe similar activity in Saturn's kilometric radiation and magnetic fields, although the “flash” must be shifted to the dawn‐to‐noon sector.
Multilocalization data assimilation for predicting heavy precipitation associated with a multiscale weather system
Authors: Yang Shu‐Chih , Chen Shu‐Hua , Kondo Keichii , Miyoshi Takemasa , Liou Yu‐Chieng , Teng Yung‐Lin , Chang Hui‐Ling
Published: June 2017

High‐resolution numerical simulations are regularly used for severe weather forecasts. To improve model initial conditions, a single short localization is commonly applied in the ensemble Kalman filter when assimilating observations. This approach prevents large‐scale corrections from appearing in a high‐resolution analysis. To improve heavy rainfall forecasts associated with a multiscale weather system, analyses must be accurate across a range of spatial scales, a task that is difficult to accomplish using a single localization. This study is the first to apply a dual‐localization (DL) method to improve high‐resolution analyses used to forecast a real‐case heavy rainfall event associated with a Meiyu front on 16 June 2008 in Taiwan. A Meiyu front is a multiscale weather system characterized by storm‐scale convection, a mesoscale front, and large‐scale southwesterly monsoonal flow. The use of the DL method to produce the analyses was able to correct both the synoptic‐scale moisture flux transported by southwesterly monsoonal flow and the mesoscale low‐level convergence offshore of southwestern Taiwan. As a result, the forecasted amount, pattern, and temporal evolution of the heavy rainfall event were improved.
Implementation and calibration of a stochastic multicloud convective parameterization in the NCEP Climate Forecast System (CFSv2)
Authors: Goswami B. B. , Khouider B. , Phani R. , Mukhopadhyay P. , Majda A. J.
Published: June 2017

A comparative analysis of fourteen 5 year long climate simulations produced by the National Centers for Environmental Predictions (NCEP) Climate Forecast System version 2 (CFSv2), in which a stochastic multicloud (SMCM) cumulus parameterization is implemented, is presented here. These 5 year runs are made with different sets of parameters in order to figure out the best model configuration based on a suite of state‐of‐the‐art metrics. This analysis is also a systematic attempt to understand the model sensitivity to the SMCM parameters. The model is found to be resilient to minor changes in the parameters used implying robustness of the SMCM formulation. The model is found to be most sensitive to the midtropospheric dryness parameter (MTD) and to the stratiform cloud decay timescale (τ30). MTD is more effective in controlling the global mean precipitation and its distribution while τ30 has more effect on the organization of convection as noticed in the simulation of the Madden‐Julian oscillation (MJO). This is consistent with the fact that in the SMCM formulation, midtropospheric humidity controls the deepening of convection and stratiform clouds control the backward tilt of tropospheric heating and the strength of unsaturated downdrafts which cool and dry the boundary layer and trigger the propagation of organized convection. Many other studies have also found midtropospheric humidity to be a key factor in the capacity of a global climate model to simulate organized convection on the synoptic and intraseasonal scales.
Controlling the Color of Plasmonic Substrates with Inkjet Printing
Authors: Duempelmann Luc , Müller Judith A. , Lütolf Fabian , Gallinet Benjamin , Ferrini Rolando , Novotny Lukas
Published: June 2017

This study introduces a versatile method for modifying the optical properties of plasmonic substrates by inkjet printing of commercially available, transparent inks with various refractive indices. The large‐scale and cost‐efficient process is demonstrated on tilted aluminum nanolamellas. They show vivid and bright colors based on a Fano resonance, which is highly susceptible to the surrounding material. Furthermore, color rendering can be made strongly angle‐dependent and asymmetric, which is in contrast to the nonvariable color generation enabled by conventional inkjet printing.
Gold‐Catalyzed Cycloisomerizations of Functionalyzed Cyclopropyl Alkynes: the Cases of Carboxamides and Alcohols
Authors: Fernández‐García Jesús M. , Garro Hugo A. , Fernández‐García Laura , García‐García Patricia , Fernández‐Rodríguez Manuel A. , Merino Isabel , Aguilar Enrique
Published: June 2017

Push‐pull alkynylcyclopropane derivatives are claimed as suitable and active substrates for gold‐catalyzed transformations. Thus, 2(3H)‐azepinones can be readily prepared from alkynylcyclopropanecarboxamides through a nucleophilic addition/cyclopropane ring‐opening cascade process and, in this manuscript, the scope and the limitations of such reaction sequence are reported. The cascade reaction is general and occurs with complete regio‐ and quimioselection to form the seven‐membered heterocycles with the exception of primary alkyl‐substituted alkynylcyclopropanecarboxamides that render 4‐methoxy‐6‐oxo‐4‐enenitriles in moderate yields. Additionally, less activated alkynylcyclopropylmethanols undergo regioselective cycloisomerization at low temperature leading to oxabicyclo[4.1.0]heptanes. Notably, the cyclopropane ring opening of these adducts takes place under thermal conditions to form dihydropyranones.

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“A picture is worth a thousand words”: Reverse image lookup and digital library assessment
Authors: Thompson Santi , Reilly Michele
Published: June 2017

This brief communication builds on the application of content‐based image retrieval (CBIR) and reverse image lookup (RIL), a graduated form of CBIR, as assessment tools for digital library image reuse. It combines literature on the definition, history, usefulness, and limitations of RIL and includes a brief analysis of the 4 published digital library image reuse assessment case studies. In its conclusion, the communication paper proposes that RIL offers benefits for digital library managers in the assessment of their collections.
Audition‐specific temporal processing deficits associated with language function in children with autism spectrum disorder
Authors: Foss‐Feig Jennifer H. , Schauder Kimberly B. , Key Alexandra P. , Wallace Mark T. , Stone Wendy L.
Published: June 2017

Sensory processing alterations are highly prevalent in autism spectrum disorder (ASD). Neurobiologically‐based theories of ASD propose that abnormalities in the processing of temporal aspects of sensory input could underlie core symptoms of ASD. For example, rapid auditory temporal processing is critical for speech perception, and language difficulties are central to the social communication deficits defining the disorder. This study assessed visual and auditory temporal processing abilities and tested their relation to core ASD symptoms. 53 children (26 ASD, 27 TD) completed visual and auditory psychophysical gap detection tasks to measure gap detection thresholds (i.e., the minimum interval between sequential stimuli needed for individuals to perceive an interruption between the stimuli) in each domain. Children were also administered standardized language assessments such that the relation between individual differences in auditory gap detection thresholds and degree of language and communication difficulties among children with ASD could be assessed. Children with ASD had substantially higher auditory gap detection thresholds compared to children with TD, and auditory gap detection thresholds were correlated significantly with several measures of language processing in this population. No group differences were observed in the visual temporal processing. Results indicate a domain‐specific impairment in rapid auditory temporal processing in ASD that is associated with greater difficulties in language processing. Findings provide qualified support for temporal processing theories of ASD and highlight the need for future research testing the nature, extent, and universality of auditory temporal processing deficits in this population. Autism Res 2017, 10: 1845–1856. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Lay Summary

Sensory symptoms are common in ASD. Temporal processing alterations are often implicated, but understudied. The ability to process rapid sensory information, particularly auditory input, is critical for language functioning. This study tested auditory and visual temporal processing in ASD and controls. Findings suggest that rapid auditory (but not visual) processing is impaired in ASD and related to language functioning. These results could provide mechanistic clues to understanding core symptoms and lead to novel intervention targets.
Die semiintegralen Spannbeton‐Viadukte im Zuge der neuen Autobahn A 11 bei Brügge
Authors: Schlaich Mike , Wenger Philipp , Behrmann Tilo , Burkhardt Uwe
Published: June 2017

Bei Brügge in Belgien wird mit der A 11 zurzeit ein neuer, 12 km langer Autobahnabschnitt als ÖPP‐Projekt realisiert. Da der Straßenzug einen Kanal in einer Höhe von 16 m quert, sind links und rechts des Kanals längere Viadukte erforderlich. Nach Fertigstellung im Sommer 2017 übernimmt das mit der Ausführung betraute Konsortium Via Brugge auch die Instandhaltung für eine Dauer von 20 Jahren. Dies ist einer der Gründe, warum die Viadukte größtenteils als integrale bzw. semiintegrale Bauwerke geplant wurden. Der monolithische Anschluss des als Massivplatte ausgeführten Spannbetonüberbaus an schlanke Pfeilerscheiben erlaubt es, die Anzahl der wartungsintensiven Brückenlager zu reduzieren. Im Bericht werden die besonderen Aspekte und Herausforderungen bei der Planung und Bauausführung am Beispiel des 770 m langen Viadukts K032 erläutert, der längsten von insgesamt acht Brücken, die in diesem Abschnitt von schlaich bergermann partner geplant wurden. Von großer Bedeutung in der Planung sind die genaue Kenntnis und Wahl der Betonparameter, welche die für die Bemessung maßgebenden Zwangsverformungen aus Kriechen, Schwinden und Temperatur beeinflussen.