bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation and Comparison of Performance in the Disc Filter with Sand Filters of Filtration Equipment in Micro Irrigation Systems
Authors: Ghaffari Masoud , Soltani Jaber
Published: August 2016

At the present time, the need to evacuate organic and green growth of algae contaminants in   micro irrigation system is expanding increasingly. The worldwide populace is expanding and as a result of this, the world may encounter extraordinary fresh water shortage. Our water assets are constrained and, subsequently, water treatment and reusing strategies are the main choices for getting crisp and fresh water in the coming decades. This study examines the rate of the impact of green growth of algae existing in micro irrigation system performance on the disc filters and sand tanks in the examination field of water, soil and horticultural and agricultural commercial enterprises Vice-Presidency of Karaj.The analyses were performed in four scenarios comprising of ordinary disc filter together with sand tank, automated disc filter together with sand tank, automated disc filter without sand tank lastly common ordinary disc filter without sand tank. These scenarios were assessed and looked at in three classifications of physical quality of irrigation system water. Data collection and experiments was run up to three months. The results of the experiments demonstrated that concentration of organic and suspended materials is viewed as safe for low flow emitters. In the range of 50 through 100 mg per liter, automated disc filters represented a good performance. In the concentration of 100 mg/l or higher, the performance of disc filters significantly decreased; subsequently it is important to put the sand tank before disc filters.
Assessment of Modern Banking Services to Achieve and Realization of E-Commerce and Its Impact on the Profitability of Banks Listed on the Tehran Stock Exchange
Authors: Mahmoodi Sadeqh , Naderi Hossein
Published: August 2016

The aim of this study was to investigate new banking services in order to achieve and the realization of e-commerce and its impact on banks' profitability listed on the stock exchange. This study is an applied research and from the logic implementation is descriptive survey study and the relationship between variables is correlation. In this study, data collection is by using library and field method, according to research hypotheses simple two-variable linear regression model was used. In this study, panel data is used to estimate and analyze quantitative and analytical and descriptive models by using Spss software. Among 3,000 delegates, managers and employees eight banks listed on the Tehran Stock Exchange using cluster sampling of 300 randomly selected as a population, and has been done during the period 2014-2015.The results of Pearson correlation coefficient between the variables of new services banking and e-commerce and profitability is equal to (0.144), which indicates that new services bank has positive impact significant on the Tehran Stock Exchange in order to fulfill ecommerce and profitability of listed banks, which means that a variety of modern banking services and increasing their use not only further caused the fulfill of e-commerce, but also increased the profitability of banks and has a direct impact on the profitability of them.
A Simple and Sensitive Voltammetric Method for the Determination of Orange II Based on a Functionalized Graphene-Modified Electrode
Authors: Gao Yudong , Xie Zhengkun , Zhang Yulong , Zou Lina , Ye Baoxian
Published: August 2016

A simple and sensitive voltammetric sensor for Orange II was developed, based on a poly(sodium p-styrenesulfonate)-functionalized graphene-modified glassy carbon electrode. This voltammetric sensor showed strong accumulation ability and an excellent voltammetric response for Orange II. The electrochemical behavior of Orange II was systematically investigated in a pH 7.0 phosphate buffer solution. By linear sweep voltammetry, under optimum conditions, a good linear relationship was obtained between peak currents and Orange II concentrations in the wider range of 3 × 10−8 to 5 × 10−6 mol/L, with an LOD of 1 × 10−8 mol/L. In addition, the proposed Orange II sensor was successfully applied to real food samples with satisfactory recovery.
EPISTEMOLOGIA DA ARTE: O FRUIDOR E O OBJETO DE ARTE
Authors:   Universidade Federal de Rondônia, Cocchieri Tiziana
Published: August 2016

Por meio deste artigo, trazemos uma perspectiva da relação sujeito/objeto, frui- dor/objeto de arte, refletida no prisma das implicações presentes no processo de cons- trução de significado da leitura de imagem. As considerações apontadas são tecidas a partir do objeto de arte, traduzidas por meio da multiplicidade de leituras possíveis, que fornecem subsídios enfatizando a subjeti- vidade como volição, porém, dissertando a partir de caminhos de significação objetivá- veis. Para explicitar esta relação, o primeiro aspecto a ser exposto diz respeito ao caráter expressivo da necessidade da razão como parte do processo que faz emergir significa- do, considerando extremos conceituais e os conteúdos de verdade das múltiplas facetas do objeto de arte, fundindo-se ao conteúdo crítico deontológico. O segundo ponto, par- te da tese sobre a qual a arte se delineia me- diante espaço conceitual, formado a partir da subjetividade que se inicia no sujeito que configura o objeto. Neste contexto, os obje- tos de arte apontam para a subjetividade do artista e do fruidor na construção de sentido, por meio de um processo imbricado de cria- ção, em que seu contraponto se apoia sobre a objetividade da realidade material do obje- to reverberada através do repertório concei- tual do sujeito. Trazemos também para este contexto a autonomia presente na cons- trução de significação conceitual enquanto substrato de verdades possíveis, com intuito de delinear campos de significação.
Hearths in the coastal areas of northernmost Sweden, from the period AD 800 to 1950
Authors: Liedgren Lars , Bergman Ingela , Ramqvist Per H. , Hörnberg Greger
Published: August 2016

This paper presents a study of the chronological setting of hearths registered in FMIS (digital register containing records of all known ancient monuments in Sweden) in the provinces of Västerbotten and Norrbotten, Northern Sweden. A total of c. 1500 hearths are known in the area, mainly situated north of the river Skellefteälven. Within a study area of 107 x 94 km, 32 hearths were randomly selected for excavation, each site embracing 1-14 hearths. The sites were scanned using a metal detector and nearly all artifacts found were from the period AD 1600-1900. 14C-datings of charcoal and burned bones corroborated that most hearths were used during this period, with a large number dating to the 19th and 20th centuries. Many hearths contained bones from mature reindeer, indicating that the hearths were related to reindeer herding. We suggest that most hearths are related to nomadic Sami reindeer herders using coastal areas for winter pasture, possibly resulting from the breakdown of the “lappskatteland” (taxation lands) system and an increase in reindeer numbers.
Evolution of crystal imperfections during current-stress ageing tests of green InGaN light-emitting diodes
Authors: Lin Yue , Peng Zhangbao , Zhu Lihong , Yan Wei , Shih Tien-mo , Wu Tingzhu , Lu Yijun , Gao Yulin , Chen Zhong , Guo Ziquan , Liu Zhuguang
Published: August 2016

We perform ageing tests under high current on several green InGaN light-emitting diodes and compare the luminous homogeneities of chip surfaces, shapes of external quantum efficiency (EQE) curves, and electroluminescence spectra during different ageing stages. By curve fittings to the EQE curves, with the ABC and two-level models, we discover that a high injection current density can modify the defect configuration in quantum wells even at room temperature, as high-temperature annealing can. For In-rich devices, the removal of localization centers is another origin of luminous intensity decay in addition to the formation of point defects.
Interfacial engineering of MoS2/TiO2 hybrids for enhanced electrocatalytic hydrogen evolution reaction
Authors: Song Xiaolin , Chen Guifeng , Guan Lixiu , Zhang Hui , Tao Junguang
Published: August 2016

Herein, we show that the synergistic effect between MoS2 and TiO2 enhances the hydrogen evolution reaction (HER) performance of their hybrids, which is tunable via interface engineering. Among several interfaces, MoS2/TiO2–H complexes exhibit the best HER activity. The observed Tafel slope of 66.9 mV/dec is well in range of previous literature reports, suggesting a Volmer–Heyrovsky mechanism. Enhanced activities were attributed to abundant active sites at the interfaces, as well as improved charge transfer efficiency. Our results emphasize the roles that interfaces play in enhancing the HER activities of MoS2-based heterogeneous catalysts.
Current-driven domain wall motion due to volume spin transfer torque in Co/Ni multilayer systems on Au underlayer
Authors: Ryu Kwang-Su , Yang See-Hun , Thomas Luc , Parkin Stuart
Published: August 2016

We have studied the current-induced domain wall (CIDW) dynamics in perpendicularly magnetized Co/Ni multilayers deposited on Au underlayer, where the conventional spin transfer torque governs the domain wall dynamics, by the Kerr microscope. It is found that the DW angle tilting following Oersted field profile plays an important role in domain wall (DW) motion at high current density J by decreasing DW velocity with the increasing J, while distorting its DW morphology. Also we find that the DW pinning becomes pronounced as the anisotropy decreases by increasing number of Co/Ni repeats. Most remarkably, the DW tilting angle changes its sign by inserting ultrathin Pt layer between Au and Co layer, which suggests that the Dzyaloshinskii–Moriya interaction and spin Hall effect induces opposite effect in DW tilting. Our findings can be of use for application of CIDW to spintronics with perpendicularly magnetized systems.
Highly accurate servo control of reference beam angle in holographic memory with polarized servo beam
Authors: Hosaka Makoto , Ogata Takeshi , Yamada Kenichiro , Yamazaki Kazuyoshi , Shimada Kenichi
Published: August 2016

We propose a new servo technique for controlling the reference beam angle in angular multiplexing holographic memory to attain higher capacity and higher speed data archiving. An orthogonally polarized beam with an incident angle slightly different from that of the reference beam is newly applied to the optics. The control signal for the servo is generated as the difference between the diffracted light intensities of these two beams from a hologram. The incident angle difference between the beams to the medium was optimized as sufficient properties of the control signal were obtained. The high accuracy of the control signal with an angle error lower than 1.5 mdeg was successfully confirmed in the simulations and experiments.
Effects of salinity change on two superoxide dismutases (SODs) in juvenile marbled eelAnguilla marmorata
Authors: Wang Li , Wang Xiaolu , Yin Shaowu
Published: August 2016

Salinity is one of the most important factors that affect the fish growth and survival. Superoxide dismutases (SODs), as the primary antioxidant enzymes, play a first role in the process of preventing oxidative stress caused by excessive superoxide anion (O${}_{2}^{-}$) in living organisms. In the present study, we investigated the effects of salinity on the gene expressions as well as enzymatic activities of MnSOD and Cu/ZnSOD in gill, intestine, kidney, liver and muscle tissues of the marbled eelAnguilla marmorata. We found that the liver might possess stronger redox capacity compared with other tissues. Furthermore, the gene expressions and enzymatic activities of SODs in juvenile marbled eels could be effectively enhanced by low salinity but inhibited when the salinity was higher than the body tolerance. Our findings indicated that MnSOD and Cu/ZnSOD played vital roles in the adaptation of marbled eels to salinity variation, which contributed to the elucidation of physiological adaptation and regulatory mechanism of SODs in eels.
A framework for smartphone-enabled, patient-generated health data analysis
Authors: Gollamudi Shreya S. , Topol Eric J. , Wineinger Nathan E.
Published: August 2016

Background:Digital medicine and smartphone-enabled health technologies provide a novel source of human health and human biology data. However, in part due to its intricacies, few methods have been established to analyze and interpret data in this domain. We previously conducted a six-month interventional trial examining the efficacy of a comprehensive smartphone-based health monitoring program for individuals with chronic disease. This included 38 individuals with hypertension who recorded 6,290 blood pressure readings over the trial.

Methods:In the present study, we provide a hypothesis testing framework for unstructured time series data, typical of patient-generated mobile device data. We used a mixed model approach for unequally spaced repeated measures using autoregressive and generalized autoregressive models, and applied this to the blood pressure data generated in this trial.

Results:We were able to detect, roughly, a 2 mmHg decrease in both systolic and diastolic blood pressure over the course of the trial despite considerable intra- and inter-individual variation. Furthermore, by supplementing this finding by using a sequential analysis approach, we observed this result over three months prior to the official study end—highlighting the effectiveness of leveraging the digital nature of this data source to form timely conclusions.

Conclusions:Health data generated through the use of smartphones and other mobile devices allow individuals the opportunity to make informed health decisions, and provide researchers the opportunity to address innovative health and biology questions. The hypothesis testing framework we present can be applied in future studies utilizing digital medicine technology or implemented in the technology itself to support the quantified self.
Prediction of M2 tidal surface currents by a global baroclinic ocean model and evaluation using observed drifter trajectories
Authors: Kodaira Tsubasa , Thompson Keith R. , Bernier Natacha B.
Published: August 2016

Global M2 tidal surface currents are predicted using a global baroclinic ocean model with horizontal grid spacing of 1/12° and 19 z‐levels in the vertical. After first showing the predicted tidal elevations are in reasonable agreement with observations made by bottom pressure recorders and altimeters, the predicted tidal surface currents are evaluated by comparing them with independent estimates based on observed drifter trajectories. Both predicted and observed tidal surface currents can exceed 0.1 m s−1 in the deep ocean. Internal tides are shown to make a significant contribution to the predicted tidal surface currents. Phase locking of the surface and internal tides causes spatial changes in the predicted tidal surface currents that vary with approximately the same wavenumber as that of the lowest mode internal tide. Qualitatively similar, small‐scale variations are also detected in the observed estimates but the variations do not line up exactly with the predictions. Possible explanations for the mismatch are given. The seasonal variation of M2 tidal surface currents, and the energy conversion rate from surface to internal tides, is also predicted by initializing, and restoring, the model to an observed seasonal climatology of temperature and salinity. Compared to tidal elevation, the seasonal change of tidal surface current can be large (order 10% for each hemisphere). It is caused by seasonal variations in the vertical structure of the baroclinic modes and the energy conversion rate. In the vicinity of major bathymetric features, the seasonal variation of second and higher order modes can be much larger (up to 50%).
Identification and intercomparison of surface‐based inversions over Antarctica from IASI, ERA‐Interim, and Concordiasi dropsonde data
Authors: Boylan Patrick , Wang Junhong , Cohn Stephen A. , Hultberg Tim , August Thomas
Published: August 2016

Surface‐based temperature inversions (SBIs) occur frequently over Antarctica and play an important role in climate and weather. Antarctic SBIs are examined during the austral spring of 2010 using measurements from dropsondes, ERA‐Interim Atmospheric Reanalysis Model, and the recently released version 6 of the Infrared Atmospheric Sounding Interferometer (IASI) level 2 product. A SBI detection algorithm is applied to temperature profiles from these data sets. The results will be used to determine if satellite and reanalysis products can accurately characterize SBIs, and if so, then they may be used to study SBIs outside of the spring 2010 study period. From the dropsonde data, SBIs occur in 20% of profiles over sea ice and 54% of profiles over land. IASI and ERA‐Interim surface air temperatures are found to be significantly warmer than dropsonde observations at high plateau regions, while IASI surface air temperatures are colder over sea ice. IASI and ERA‐Interim have a cold bias at nearly all levels above the surface when compared to the dropsonde. SBIs are characterized by their frequency, depth, and intensity. It is found that SBIs are more prevalent, deeper, and more intense over the continent than over sea ice, especially at higher surface elevations. Using IASI and ERA‐Interim data the detection algorithm has a high probability of detection of SBIs but is found to severely overestimate the depth and underestimate the intensity for both data sets. These overestimation and underestimation are primarily due to the existence of extremely shallow inversion layers that neither satellite nor reanalysis products can resolve.
Quantifying uncertainties on regional sea level change induced by multidecadal intrinsic oceanic variability
Authors: Sérazin Guillaume , Meyssignac Benoit , Penduff Thierry , Terray Laurent , Barnier Bernard , Molines Jean‐Marc
Published: August 2016

A global eddy‐permitting (1/4° resolution) ocean general circulation model is shown to spontaneously generate intrinsic oceanic variability (IOV) up to multidecadal timescales (T > 20 years) under a repeated seasonal atmospheric forcing. In eddy‐active regions, the signature of this multidecadal eddy‐driven IOV on sea level is substantial, weakly autocorrelated, and is comparable to (and may clearly exceed) the corresponding signature of internal climate variability (ICV) produced by current coupled climate models—whose laminar ocean components may strongly underestimate IOV. Deriving sea level trends from finite‐length time series in eddy‐active regions yields uncertainties induced by this multidecadal IOV, which are of the same order of magnitude as those due to ICV. A white noise model is proposed to approximate the low‐frequency tail of the IOV spectra and could be used to update ICV estimates from current climate simulations and projections.
A statistical study of EMIC rising and falling tone emissions observed by THEMIS
Authors: Nakamura Satoko , Omura Yoshiharu , Angelopoulos Vassilis
Published: August 2016

Electromagnetic ion cyclotron (EMIC) waves with rising or falling frequency variations have been studied intensively because of their effects on energetic particles in the Earth's magnetosphere. We develop an automated classification method of EMIC events based on the characteristics of frequency variations. We report some basic statistical properties of frequency variations in EMIC waves observed over 5–10 RE by three Time History of Events and Macroscale Interactions during Substorms probes from January 2012 to December 2014. We clarify whether rising tones or falling tones are observed in each chosen 20 min time segment. In the present analysis, we find that the occurrence rate of EMIC rising or falling tone events is more than 30% of the total EMIC wave events. The dayside magnetosphere is a preferential region for the EMIC frequency variations. The occurrence rate of rising tone events is slightly greater than that of falling tone events. We examine the relation between the frequency characteristics and the magnetospheric conditions. The solar wind pressure strongly controls the occurrence rates of frequency variations. We also calculate ranges of frequency variations. Large‐amplitude EMIC waves tend to have wider frequency variations, and the range of frequency variation is largest around the prenoon region. In addition, rapid variations in wave amplitudes called “subpacket structures” are found in 70% of the EMIC rising or falling tone events in the dayside region. Subpacket structures appear mainly in large‐amplitude EMIC rising or falling tones. These features are consistent with nonlinear wave growth theory.
Wave‐driven gradual loss of energetic electrons in the slot region
Authors: He Zhaoguo , Yan Qi , Chu Yuchuan , Cao Yong
Published: August 2016

Resonant pitch angle scattering by plasmaspheric hiss has long been considered to be responsible for the energetic electron loss in the slot region, but the detailed quantitative comparison between theory and observations is still lacking. Here we focus on the loss of 100–600 keV electrons at L = 3 during the recovery phase of a geomagnetic storm on 28 June 2013. Van Allen Probes data showed the concurrence of intense (with power up to 10−4 nT2/Hz) plasmaspheric hiss waves and significant (up to 1 order) loss of energetic electrons within 2 days. Our quasi‐linear diffusion simulations show that hiss scattering can basically reproduce the temporal evolution of the angular distribution of the observed electron flux decay. This quantitative analysis provides further support for the mechanism of hiss‐driven electron loss in the slot region.
Cobalt‐Catalyzed Reductive Cross‐Coupling Between Benzyl Chlorides and Aryl Halides
Authors: Pal Suman , Chowdhury Sushobhan , Rozwadowski Elodie , Auffrant Audrey , Gosmini Corinne
Published: August 2016

A new protocol for the direct reductive cobalt‐catalyzed arylation of benzyl chlorides has been developed in order to form functionalized diarylmethanes. A variety of reactive groups either on the aryl or the benzyl halide was employed. This represents the first cobalt‐catalyzed reductive cross‐coupling which does not require any ligand and pyridine. A reaction pathway is proposed involving a radical benzyl species.

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Natural Dye Cyanidin‐Based Polyacrylonitrile Conjugate as Environmental‐Friendly Thin Film Sensor
Authors: Fares Mohammad M. , Masadeh Khansa'a H.
Published: August 2016

Natural dye cyanidin extracted from red cabbage and adsorbed on the surface of polyacrylonitrile (PAN) in the presence of epichlorohydrin coupling agent to form transparent environmental‐friendly thin‐film sensor was achieved. The potential thin film showed successful sensor behavior and demonstrated gradual and reversible sensing change in the pH range of 2.0–11.0. Visual and Lucid color change of the thin film was observed at inclined pH value; fuchsia color at pH 1–3, purple color at pH 6–8, and blue color at pH 10–11. Structural identification of the thin‐film sensor provided evidence of physical adsorption of cyanidin on the surface of PAN via epichlorohydrin coupling agent as prevailed by FTIR spectroscopy. Moreover, the thin‐film sensor demonstrated thermal stability up to 105°C, as onset degradation temperature, as verified by thermogravimetric analysis (TGA) and its first derivative (DTG) techniques. Moreover, the pH‐sensing change of the 1‐mm‐thick thin film was checked by UV‐Vis technique. The oligomer formation of cyanidin, mediated by epichlorohydrin, lead to the formation of stable and successful adsorption on the surface of PAN with uniform and soft appearance. The concept of the reversible stability and response time of the thin film sensor were also proved. The cyanidin‐based PAN conjugate sensor act as a novel environmental‐friendly sensor with the following specifications: low cost, easy fabrication, high sensing capacity, appropriate reversible stability, and response time specifications. Such exquisite specifications of the thin‐film sensor adapt it to put into service in optoelectronics and microelectronic devices.
Argon glow discharge plasma‐reduced palladium nanoparticles supported on activated carbon for Suzuki and Heck coupling reactions
Authors: Liu Yang , Bai Xuefeng
Published: August 2016

Palladium nanoparticles supported on activated carbon were prepared by argon glow discharge plasma reduction (Pd/C‐P) without any chemical reducing agents and protective agents. The as‐prepared Pd/C‐P catalyst was characterized using nitrogen adsorption–desorption, X‐ray diffraction and transmission electron microscopy analyses. The results showed that the palladium nanoparticles reduced by plasma are well dispersed with a smaller particle size than commercial Pd/C. Pd/C‐P exhibited a high catalytic activity in Suzuki and Heck coupling reactions. Moreover, there was no obvious loss of catalytic activity even after eight repeated cycles, showing good reactivity and recyclability.
Lightning activity in the Mediterranean: quantification of cyclones contribution and relation to their intensity
Authors: Galanaki Elissavet , Flaounas Emmanouil , Kotroni Vassiliki , Lagouvardos Konstantinos , Argiriou Athanassios
Published: August 2016

A 10‐year data set of intense Mediterranean cyclones was used for a twofold objective: first to quantify the cyclone's contribution to lightning occurrence in the region and second to investigate potential connection of lightning with cyclones intensity. For this reason, we used cyclone tracks, lightning observations and reanalysis from the European Centre for Medium Range Weather Forecasts, for the 10‐year period of 2005–2014. Results showed that intense cyclones provoke <10% of lightning activity over the Mediterranean Sea, however, in certain areas, cyclone contributions might reach 20–30%.

The intense cyclones, which are associated with lightning activity close to their centre, constitute about one third (36%) of the total number of tracked cyclones. Therefore two cyclone groups are identified: those associated with and those without lightning. The first group presents in average 35% more ice and 15% more liquid cloud water content within the upper and lower atmospheric levels, respectively, while is related to approximately three times greater values of convective available potential energy in average. Further analysis shows that the intensities of the cyclones in the two groups present no significant differences, suggesting that deep convection may not be a major mechanism for the occurrence of intense Mediterranean cyclones. Finally, we show that cyclones associated with lightning present the highest lightning activity about 6 h prior to the cyclones maximum intensity.
Genome‐Wide Assessment of the Binding Effects of Artificial Transcriptional Activators by High‐Throughput Sequencing
Authors: Chandran Anandhakumar , Syed Junetha , Li Yue , Sato Shinsuke , Bando Toshikazu , Sugiyama Hiroshi
Published: August 2016

One of the major goals in DNA‐based personalized medicine is the development of sequence‐specific small molecules to target the genome. SAHA‐PIPs belong to such class of small molecule. In the context of the complex eukaryotic genome, the differential biological effects of SAHA‐PIPs are unclear. This question can be addressed by identifying the binding regions across the genome; however, it is a challenge to enrich small‐molecule‐bound DNA without chemical crosslinking. Here, we developed a method that employs high‐throughput sequencing to map the binding area of small molecules throughout the chromatinized human genome. Analysis of the sequenced data confirmed the presence of specific binding sites for SAHA‐PIPs from the enriched sequence reads. Mapping the binding sites and enriched regions on the human genome clarifies the reason for the distinct biological effects of SAHA‐PIP. This approach will be useful for identifying the function of other small molecules on a large scale.
Minimalist Antibodies and Mimetics: An Update and Recent Applications
Authors: Bruce Virginia J. , Ta Angeline N. , McNaughton Brian R.
Published: August 2016

The immune system utilizes antibodies to recognize foreign or disease‐relevant receptors, initiating an immune response to destroy unwelcomed guests. Because researchers can evolve antibodies to bind virtually any target, it is perhaps unsurprising that these reagents, and their small‐molecule conjugates, are used extensively in clinical and basic research environments. However, virtues of antibodies are countered by significant challenges. Foremost among these is the need for expression in mammalian cells (largely due to often necessary post‐translational modifications). In response to these challenges, researchers have developed an array of minimalist antibodies and mimetics, which are smaller, more stable, simpler to express in Escherichia coli, and amendable to laboratory evolution and protein engineering. Here we describe these scaffolds and discuss recent applications of minimalist antibodies and mimetics.
SMT‐based context‐bounded model checking for CUDA programs
Authors: Pereira Phillipe , Albuquerque Higo , da Silva Isabela , Marques Hendrio , Monteiro Felipe , Ferreira Ricardo , Cordeiro Lucas
Published: August 2016

We present ESBMC‐GPU tool, an extension to the Efficient SMT‐Based Context‐Bounded Model Checker (ESBMC), which is aimed at verifying Graphics Processing Unit (GPU) programs written for the Compute Unified Device Architecture (CUDA) platform. ESBMC‐GPU uses an operational model, that is, an abstract representation of the standard CUDA libraries, which conservatively approximates their semantics, in order to verify CUDA‐based programs. It then explicitly explores the possible interleavings (up to the given context bound), while treats each interleaving itself symbolically. Additionally, ESBMC‐GPU employs the monotonic partial order reduction and the two‐thread analysis to prune the state space exploration. Experimental results show that ESBMC‐GPU can successfully verify 82% of all benchmarks, while keeping lower rates of false results. Going further than previous attempts, ESBMC‐GPU is able to detect more properties violations than other existing GPU verifiers due to its ability to verify errors of the program execution flow and to detect array out‐of‐bounds and data race violations. Copyright © 2016 John Wiley & Sons, Ltd.
Methods for the Detection of Autophagy in Mammalian Cells
Authors: Zhang Ziyan , Singh Rajat , Aschner Michael
Published: August 2016

Macroautophagy (hereafter referred to as autophagy) is a degradation pathway that delivers cytoplasmic materials to lysosomes via double‐membraned vesicles designated autophagosomes. Cytoplasmic constituents are sequestered into autophagosomes, which subsequently fuse with lysosomes, where the cargo is degraded. Autophagy is a crucial mechanism involved in many aspects of cell function, including cellular metabolism and energy balance; alterations in autophagy have been linked to various human pathological processes. Thus, methods that accurately measure autophagic activity are necessary. In this unit, we introduce several approaches to analyze autophagy in mammalian cells, including immunoblotting analysis of LC3 and p62, detection of autophagosome formation by fluorescence microscopy, and monitoring autophagosome maturation by tandem mRFP‐GFP fluorescence microscopy. Overall, we recommend a combined use of multiple methods to accurately assess the autophagic activity in any given biological setting. © 2016 by John Wiley & Sons, Inc.
Neural plasticity following lesions of the primate occipital lobe: The marmoset as an animal model for studies of blindsight
Authors: Hagan Maureen A. , Rosa Marcello G. P. , Lui Leo L.
Published: August 2016

For nearly a century it has been observed that some residual visually guided behavior can persist after damage to the primary visual cortex (V1) in primates. The age at which damage to V1 occurs leads to different outcomes, with V1 lesions in infancy allowing better preservation of visual faculties in comparison with those incurred in adulthood. While adult V1 lesions may still allow retention of some limited visual abilities, these are subconscious—a characteristic that has led to this form of residual vision being referred to as blindsight. The neural basis of blindsight has been of great interest to the neuroscience community, with particular focus on understanding the contributions of the different subcortical pathways and cortical areas that may underlie this phenomenon. More recently, research has started to address which forms of neural plasticity occur following V1 lesions at different ages, including work using marmoset monkeys. The relatively rapid postnatal development of this species, allied to the lissencephalic brains and well‐characterized visual cortex provide significant technical advantages, which allow controlled experiments exploring visual function in the absence of V1. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 314–327, 2017
Construction of chromosomally encoded lacZ and gfp reporter strains of Escherichia coli for the study of global regulation of metabolism
Authors: Trachtmann Natalia , Alvarez Fong Karla Fernanda , Guitart Font Emma , Sprenger Georg A.
Published: August 2016

We developed plasmid systems pJLIC and pJLRCS that allow the easy cloning of promoter regions upstream of reporter genes (lacZ and gfp) and the subsequent transfer of the resulting reporter cassettes into the chromosome of Escherichia coli by recombineering. Thus, a promoter region can be inserted upstream of lacZ gene in the context of the lactose operon of recipient E. coli strains. Moreover, a promoter–GFP reporter is inserted at a nonessential site of the chromosome. These systems allow for selection and promoter strength analysis at the single copy level. We also provide a collection of E. coli knock‐out mutants in genes for global regulation of C, N, and O metabolism, and combinations of these mutants with the newly constructed chromosomal lacZ and gfp reporter system. This allows assaying transcriptional activities of promoters before the background of different mutants. Both lacZ and gfp reporter cassettes (including appropriate antibiotic resistance markers) and the regulator knock‐outs may be easily transferred by phage P1 mediated transduction to other E. coli strains. As a proof of principle, ß‐galactosidase activity and GFP fluorescence were compared for lacZ and gfp reporter systems placed under the control of the PrssA promoter both in a wild‐type and an isogenic rpoS‐mutant strain.
Glycerol conversion into a single cell oil by engineered Yarrowia lipolytica
Authors: Gajdoš Peter , Nicaud Jean‐Marc , Čertík Milan
Published: August 2016

Oleaginous yeasts are considered as natural single cell oil producers. Engineering the lipid biosynthetic pathway has the potential to increase lipid accumulation by these yeasts. In Yarrowia lipolytica, three diacylglycerol acyltransferases encoded by LRO1, DGA1, and DGA2 genes are involved in lipid formation. Strain JMY3580 was constructed by overexpressing DGA2 gene in Q4 strain (dga1Δ dga2Δ lro1Δ are1Δ). Reconstruction of triacylglycerol synthesis pathway led to significant improvement in lipid accumulation. Strain JMY3580 accumulated over 40% of lipids in biomass, while lipid accumulation in wild‐type strain was not able to exceed 20% when grown on a glycerol‐based medium with carbon to nitrogen ratio of 90. Higher lipid accumulation (over 50%) was achieved in fed‐batch grown cells when glycerol was added during cultivation. The best biomass yield was 18.5 g/L after 144 h with total fatty acid yield 9.9 g/L. Fatty acid composition was altered when Dga2p was the only diacylglycerol acyltransferase present in yeast cells, especially lower percentage of linoleic acid was present in lipids of JMY3580. Microbial oil prepared by conversion of glycerol by genetically engineered Y. lipolytica could be applied for various value‐added products based on single cell oils.
Comparison of trout hepatocytes and liver S9 fractions as in vitro models for predicting hepatic clearance in fish
Authors: Fay Kellie A. , Fitzsimmons Patrick N. , Hoffman Alex D. , Nichols John W.
Published: August 2016

Isolated hepatocytes and liver S9 fractions have been used to collect in vitro biotransformation data for fish as a means of improving modeled estimates of chemical bioaccumulation. To date, however, there have been few direct comparisons of these 2 methods. In the present study, cryopreserved trout hepatocytes were used to measure in vitro intrinsic clearance rates for 6 polycyclic aromatic hydrocarbons (PAHs). These rates were extrapolated to estimates of in vivo intrinsic clearance and used as inputs to a well stirred liver model to predict hepatic clearance. Predicted rates of hepatic clearance were then evaluated by comparison with measured rates determined previously using isolated perfused livers. Hepatic clearance rates predicted using hepatocytes were in good agreement with measured values (<2.1-fold difference for 5 of 6 compounds) under 2 competing binding assumptions. These findings, which may be attributed in part to high rates of PAH metabolism, are similar to those obtained previously using data from liver S9 fractions. For 1 compound (benzo[a]pyrene), the in vivo intrinsic clearance rate calculated using S9 data was 10-fold higher than that determined using hepatocytes, possibly due to a diffusion limitation on cellular uptake. Generally, however, there was good agreement between calculated in vivo intrinsic clearance rates obtained using either in vitro test system. These results suggest that both systems can be used to improve bioaccumulation assessments for fish, particularly when vitro rates of activity are relatively high, although additional work is needed to determine if the chemical domain of applicability for each system differs. Environ Toxicol Chem 2017;36:463–471. Published 2016 SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.
Activating Metal Sites for Biological Electron Transfer
Authors: Solomon Edward I. , Hadt Ryan G. , Snyder Benjamin E. R.
Published: August 2016

This review focuses on the unique spectroscopic features of the blue copper active sites. These reflect a novel electronic structure that activates the site for rapid long‐range electron transfer in its biological function. The role of the protein in determining the geometric and electronic structure of this site is defined, as is its contribution to function. This has been referred to as the entatic/rack‐induced state. These concepts are then extended to cytochrome c, which is also determined to be in an entatic state.
Comparative performance of airyscan and structured illumination superresolution microscopy in the study of the surface texture and 3D shape of pollen
Authors: Sivaguru Mayandi , Urban Michael A. , Fried Glenn , Wesseln Cassandra J. , Mander Luke , Punyasena Surangi W.
Published: August 2016

The visualization of taxonomically diagnostic features of individual pollen grains can be a challenge for many ecologically and phylogenetically important pollen types. The resolution of traditional optical microscopy is limited by the diffraction of light (250 nm), while high resolution tools such as electron microscopy are limited by laborious preparation and imaging workflows. Airyscan confocal superresolution and structured illumination superresolution (SR‐SIM) microscopy are powerful new tools for the study of nanoscale pollen morphology and three‐dimensional structure that can overcome these basic limitations. This study demonstrates their utility in capturing morphological details below the diffraction limit of light. Using three distinct pollen morphotypes (Croton hirtus, Dactylis glomerata, and Helianthus sp.) and contrast‐enhancing fluorescent staining, we were able to assess the effectiveness of the Airyscan and SR‐SIM. We further demonstrate that these new superresolution methods can be easily applied to the study of fossil pollen material.
A simple drop‐and‐detect method using porous alumina ceramics as platforms for rapid surface‐enhanced Raman spectroscopy
Authors: Lou Xiutao , Zhao Xiaorong , Lin Xiang , Zhang Meiling , Xu Lianjie , Wang Haoruo , Hasi Wuliji , Lu Zhiwei
Published: August 2016

We propose a simple and rapid surface‐enhanced Raman spectroscopy (SERS) method based on the dropping and detection of a sample droplet on a porous alumina ceramic platform (ACP). The SERS versatility of the proposed drop‐and‐detect method was demonstrated by using well‐studied water‐soluble melamine and ethanol‐soluble 4‐mercaptobenzoic acid as Raman probes. Colloidal silver nanoparticles were used as SERS substrates. Because of the fast permeation of the sample droplet by using ACPs, reproducible SERS measurements could be performed within a minute after the dropping of the sample solution. In comparison with its counterpart quartz plate, the cost‐effective ACP made the uniformity of the distribution pattern of the dried droplet improved by an order of magnitude. The measurement sensitivity was also greatly improved by using ACPs due to their enrichment functions. The lowest detectable concentrations achieved for melamine and 4‐mercaptobenzoic acid were 2.5 µg/l and 2.5 × 10−8 mol/l, respectively. The proposed drop‐and‐detect method was also demonstrated by quantitative detection of trace level melamine in liquid milk achieving a lowest detectable concentration of 0.1 mg/l, indicating its advantages of simplicity and efficiency for practical SERS applications. Copyright © 2016 John Wiley & Sons, Ltd.
The Association of Combat Exposure With Postdeployment Behavioral Health Problems Among U.S. Army Enlisted Women Returning From Afghanistan or Iraq
Authors: Adams Rachel Sayko , Nikitin Ruslan V. , Wooten Nikki R. , Williams Thomas V. , Larson Mary Jo
Published: August 2016

An association between combat exposure and postdeployment behavioral health problems has been demonstrated among U.S. military service members returning from Afghanistan or Iraq in predominantly male samples, yet few studies have focused on the experiences of women. Using data from the longitudinal, observational Substance Use and Psychological Injury Combat (SUPIC) Study, we explored the self‐report of 4 combat exposure items and postdeployment behavioral health screening results for 42,397 Army enlisted women who had returned from Afghanistan or Iraq from fiscal years 2008 through 2011. We ran multivariate logistic regression models to examine how a constructed composite combat exposure score (0, 1, 2, 3+) was associated with screening positive postdeployment for posttraumatic stress disorder (PTSD), depression, and at‐risk drinking among active duty (AD) and National Guard/Reserve (NG/R) women. AD and NG/R women commonly reported being wounded, injured, assaulted, or hurt (17.3% and 29.0%, respectively). In all 6 multivariate models, Army women with any report of combat exposure had increased odds of the behavioral health problem (i.e., PTSD, depression, or at‐risk drinking). The magnitude of the association between combat exposure and PTSD was most striking, indicating increased odds of PTSD as combat exposure score increased. AD and NG/R women with a combat exposure score of 3+ had increased odds of PTSD, 20.7, 95% confidence interval (CI) [17.0, 25.1] and 27.8, 95% CI [21.0, 36.9], respectively. Women who report combat exposure may benefit from early prevention and confidential intervention to promote postdeployment health and reduce long‐term behavioral health problems.
Synthesis of High Molecular Weight Polyetherethersulfone‐Allyl Copolymers of Controlled Glass Transition
Authors: Faye Adrien , Furtos Alexandra , Brisson Josée
Published: August 2016

Polyetherethersulfones with double bonds inserted along the main polymer chain are synthesized by polycondensation. The glass transition is modulated by increasing the size of aromatic etherethersulfone rigid blocks and decreasing the ratio of flexible allyl segments which contain a double bond. Resulting copolymers have a Mn of up to 60 000 g mol−1, moderate polydispersity indices (Đ or Ip) of 1.70 to 2.11, and are shown, by the presence of a single glass transition temperature in differential scanning calorimetry and by matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectrometry, to be random. The glass transition of copolymers follows the Gordon–Taylor relationship. The thermal resistance of copolymers increases when decreasing the amount of the flexible segment and increasing the length of the rigid block. Chemical aging of films is investigated by immersion in bleach, which is commonly used to clean membranes. Films show high resistance to bleach, therefore making this approach relevant to membrane fabrication.

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Synthetic Mimics of Antimicrobial Peptides (SMAMPs) in Layer‐by‐Layer Architectures: Possibilities and Limitations
Authors: Dorner Franziska , Malek‐Luz Alicia , Saar Julia S. , Bonaus Sebastian , Al‐Ahmad Ali , Lienkamp Karen
Published: August 2016

Polymer‐based synthetic mimics of antimicrobial peptides (SMAMPs) show promising antimicrobial activity in solution and as surface‐attached networks. In this paper, their potential as active ingredients in layer‐by‐layer (LbL) assemblies is evaluated. These consist of the weak, anionic polyelectrolyte poly(acrylic acid), and either the hydrophobic butyl SMAMP or the hydrophilic diamine SMAMP (both of which are cationic, weak polyelectrolytes). In situ surface plasmon resonance spectroscopy is used to optimize the LbL assembly conditions. An “overshooting” is observed when depositing the SMAMP layer. Zeta potential measurements show that the layer charge inversion is reduced at each build‐up step due to layer interpenetration. Thus, the positive charge of LbL assemblies with SMAMPs as the top layer is low; a significant part is consumed to maintain layer stability. This leads to reduced antimicrobial activity. Fine‐tuning of the assembly and post‐treatment conditions leads to SMAMP‐PAA LbL systems with optimized antimicrobial activity and stability.

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Diffusion‐weighted DESS protocol optimization for simultaneous mapping of the mean diffusivity, proton density and relaxation times at 3 Tesla
Authors: Gras Vincent , Farrher Ezequiel , Grinberg Farida , Shah N. Jon
Published: August 2016

Purpose

To design a general framework for the optimization of an MRI protocol based on the the diffusion‐weighted dual‐echo steady‐state (DW‐DESS) sequence, enabling quantitative and simultaneous mapping of proton density (PD), relaxation times
and
and diffusion coefficient D.

Methods

A parameterization of the DW‐DESS sequence minimizing the Cramér‐Rao lower bound of each parameter estimate was proposed and tested in a phantom experiment. An extension of the protocol was implemented for brain imaging to return the rotationally invariant mean diffusivity (MD).

Results

In an NiCl2‐doped agar gel phantom wherein
ms, the parameter estimation errors were below 3% for PD and
and below 7% for
and D while the measured signal‐to‐noise ratio always exceeded 20. In the human brain, the in vivo parametric maps obtained were overall in reasonable agreement with gold standard measurements, despite a broadening of the distributions due to physiological motion.

Conclusion

Within the optimization framework presented here, DW‐DESS images can be quantitatively interpreted to yield four intrinsic parameters of the tissue. Currently, the method is limited by the sensitivity of the DW‐DESS sequence in terms of physiological motion. Magn Reson Med 78:130–141, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Funken im Labor: kleine Brüder der Blitze
Authors: Vollmer Michael , Möllmann Klaus‐Peter
Published: August 2016

Blitze haben die Menschen schon jeher fasziniert [1], und die wissenschaftliche Blitzforschung ist seit langem ein eigenes Spezialgebiet. Ihre räumliche Ausbreitung kann man mit Hochgeschwindigkeits‐Videos sehr gut beobachten, wenn man einen Blitz gerade erwischt. Im Labor lassen sich die kleineren Brüdern der Blitze, die Funken, zwar kontrolliert erzeugen, ihre Beobachtung ist aber wegen der schnelleren zeitlichen Entwicklung schwierig.

Dieser Artikel wurde aus technischen Problemen doppelt veröffentlicht 10.1002/piuz.201690047.