bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low‐latitude gravity wave variances in the mesosphere and lower thermosphere derived from SABER temperature observation and compared with model simulation of waves generated by deep tropical convection
Authors: Walterscheid R. L. , Christensen A. B. 
Published: September 2016

AbstractA portion of waves generated by deep convection have scales and amplitudes large enough to be detected by spaceborne instruments. We have analyzed temperature data from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on the Thermosphere Ionosphere Mesosphere Energetics Dynamics (TIMED) satellite for subtidal‐scale fluctuations. Filtering was applied both vertically and horizontally to extract wave variances. We have analyzed the altitude region between 70 and 130 km and focus on the variances at equatorial latitudes for the altitude region between 70 and 120 km as a function of season, local time intervals, geographical location, and altitude. We find significant variances where convection is particularly prolific (Intertropical Convergence Zone) and at altitudes where wave trapping is known to be favored (e.g., the lower thermospheric duct). The locations of significant variances persist from year to year. Standard deviations of a few tens of kelvins are found. We have also performed simulations of the response to deep tropical convection with a time‐dependent, high‐resolution fully compressible dynamical model. Our simulations give wave amplitudes that agree reasonably well with the observed amplitudes and show layering that is consistent with the observations. Our main finding is that significant variations seen in TIMED/SABER temperature data have a convective wave source and are concentrated in layers where thermal ducts occur.
Analysis of impact crater populations and the geochronology of planetary surfaces in the inner solar system
Authors: Fassett Caleb I. 
Published: September 2016

AbstractAnalyzing the density of impact craters on planetary surfaces is the only known technique for learning their ages remotely. As a result, crater statistics have been widely analyzed on the terrestrial planets, since the timing and rates of activity are critical to understanding geologic process and history. On the Moon, the samples obtained by the Apollo and Luna missions provide critical calibration points for cratering chronology. On Mercury, Venus, and Mars, there are no similarly firm anchors for cratering rates, but chronology models have been established by extrapolating from the lunar record or by estimating their impactor fluxes in other ways. This review provides a current perspective on crater population measurements and their chronological interpretation. Emphasis is placed on how ages derived from crater statistics may be contingent on assumptions that need to be considered critically. In addition, ages estimated from crater populations are somewhat different than ages from more familiar geochronology tools (e.g., radiometric dating). Resurfacing processes that remove craters from the observed population are particularly challenging to account for, since they can introduce geologic uncertainty into results or destroy information about the formation age of a surface. Regardless of these challenges, crater statistics measurements have resulted in successful predictions later verified by other techniques, including the age of the lunar maria, the existence of a period of heavy bombardment in the Moon's first billion years, and young volcanism on Mars.
Measuring spatiotemporal variation in snow optical grain size under a subalpine forest canopy using contact spectroscopy
Authors: Molotch Noah P. , Barnard David M. , Burns Sean P. , Painter Thomas H. 
Published: September 2016

AbstractThe distribution of forest cover exerts strong controls on the spatiotemporal distribution of snow accumulation and snowmelt. The physical processes that govern these controls are poorly understood given a lack of detailed measurements of snow states. In this study, we address one of many measurement gaps by using contact spectroscopy to measure snow optical grain size at high spatial resolution in trenches dug between tree boles in a subalpine forest. Trenches were collocated with continuous measurements of snow depth and vertical profiles of snow temperature and supplemented with manual measurements of snow temperature, geometric grain size, grain type, and density from trench walls. There was a distinct difference in snow optical grain size between winter and spring periods. In winter and early spring, when facetted snow crystal types were dominant, snow optical grain size was 6% larger in canopy gaps versus under canopy positions; a difference that was smaller than the measurement uncertainty. By midspring, the magnitude of snow optical grain size differences increased dramatically and patterns of snow optical grain size became highly directional with 34% larger snow grains in areas south versus north of trees. In winter, snow temperature gradients were up to 5–15°C m−1 greater under the canopy due to shallower snow accumulation. However, in canopy gaps, snow depths were greater in fall and early winter and therefore more significant kinetic growth metamorphism occurred relative to under canopy positions, resulting in larger snow grains in canopy gaps. Our findings illustrate the novelty of our method of measuring snow optical grain size, allowing for future studies to advance the understanding of how forest and meteorological conditions interact to impact snowpack evolution.
Aptamers
Authors: Gopinath Subash C.B. 
Published: September 2016

AbstractAptamer is an artificial nucleic acid ligand, the so‐called artificial antibody, can be generated in vitro from the synthetic nucleic acid library by the process called ‘systematic evolution of ligands by exponential enrichment’ (SELEX). This process involves iterative rounds complex formation, separation, and amplification. At the end of this process, predominant aptamer will be found and it has high affinity to the cognate target. There are several modifications that have been demonstrated in the selection process with the generation of high‐affinity aptamers. The aptamer undergoes proper folding to interact with their target and fulfil the desired function. The aptamer behaves similar to the antibody and in several instances attested to be better than antibody. The aptamer and antibody complementation has also been shown with high‐performance assays. Currently, several aptamers are undergoing different clinical phase trials toward their applications in theranostics.
Chromatography of Membrane Proteins and Lipoproteins
Authors: Zolla Lello , D'Alessandro Angelo , Lana Alessandro 
Published: September 2016

AbstractThe available methods for the separation of membrane proteins and lipoproteins are sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS/PAGE), followed by immunoblotting, isoelectric focusing (IEF), and capillary electrophoresis (CE), along with the recently introduced gel‐based native techniques (blue native (BN) and clear native (CN)), and high‐performance liquid chromatography (HPLC). In this article, it is shown that HPLC techniques, given their wide versatility, relative ease of use, and high resolution, may be considered the most valuable tool for the characterization of virtually any hydrophobic protein. Application examples are described, and comparisons with other methods are discussed. Moreover, HPLC is not a destructive technique, and therefore, proteins, once separated, are available for further analytical investigations. Among these techniques, quantitative and qualitative analyses of the separated fractions can be obtained through other biophysical approaches, such as crystallography or structural spectroscopy. Most of these approaches require preliminary protein purification (90% or higher), which could be rapidly obtained through preliminary HPLC.
Flow Injection Analysis Techniques in Atomic Spectroscopy
Authors: Cruz‐Alonso María , Sanz‐Medel Alfredo , Pereiro Rosario 
Published: September 2016

AbstractFlow injection analysis (FIA), developed for the automation of serial assays, has become a powerful tool most adequate for on‐line performing any sample preparation before final measurement (e.g. sample dissolution, dilutions, matrix removal, and analyte preconcentration). It is not surprising that the combination of FIA with atomic spectrometric techniques has enlarged the analytical potential of atomic methods and expanded their field of applications, allowing also for greener procedures. The variety of sample manipulation processes that can be covered today by FIA is amazing, and therefore, the general instrumentation required is reviewed in this contribution.The description of the different flow strategies is carried out according to a hierarchy going from simple dilutions, reagent mixing, or standard additions, to more sophisticated flow manifolds such as those based on the use of two phases (e.g. gas–liquid, liquid–liquid, or solid–liquid) for separation/preconcentration purposes. Modern approaches allowing for on‐line decomposition/dissolution of solid samples (e.g. photo‐oxidation and microwave heating) are also described.The coupling of the above‐mentioned flow methodologies to a variety of atomization/excitation/ionization sources (flames, quartz tubes, graphite furnaces, inductively coupled plasmas, microwave induced plasmas, glow discharges, etc.) is detailed, aiming to show the usefulness of this combination for atomic techniques based on either photon measurements (absorption, emission, and fluorescence) or ion measurements (mass spectrometry, MS).
Fluorescence Imaging Microscopy
Authors: Lemasters John J. 
Published: September 2016

AbstractFluorescence imaging microscopy is a powerful tool to localize specific molecular components with lateral resolution of 0.2 µm. New techniques of confocal and multiphoton microscopy also permit submicrometer axial resolution even in thick specimens, and novel super‐resolution techniques that improve resolution to 0.1 µm and less are emerging. The number of specific parameter‐indicating fluorophores useful for nondestructive live cell imaging continues to increase, including markers of cell shape and volume, organelles, membrane potentials, ions, and other chemical constituents. Moreover, virtually, any cellular protein can be tagged with a fluorescent protein in the living state. These developments make fluorescence microscopy an indispensable tool for the molecular biologist, cell biologist, physiologist, and others both in and not in the life sciences.
Knee Pain and Structural Damage as Risk Factors for Incident Widespread Pain: Data From the Multicenter Osteoarthritis Study
Authors: Carlesso Lisa C. , Segal Neil A. , Curtis Jeffrey R. , Wise Barton L. , Frey Law Laura , Nevitt Michael , Neogi Tuhina 
Published: September 2016

ObjectiveTo examine the longitudinal relationship of knee pain, radiographic osteoarthritis (OA), symptomatic knee OA, and knee pain severity to incident widespread pain.MethodsThe Multicenter Osteoarthritis Study is a longitudinal cohort of persons with or at risk of knee OA. Participants were characterized as having consistent frequent knee pain, radiographic OA (Kellgren/Lawrence scale grade ≥2), symptomatic OA, and knee pain severity at the 60‐month visit (baseline). Widespread pain was categorized as pain above and below the waist, on both sides of the body and axially, using a standard homunculus, excluding knee pain. Incident widespread pain was defined as the presence of widespread pain at 84 months in those who were free of widespread pain at baseline. We assessed the relationship of baseline radiographic OA, symptomatic OA, consistent frequent knee pain, and knee pain severity, respectively, with incident widespread pain using logistic regression, adjusting for potential confounders, including models with and without pain severity.ResultsAt baseline, 1,129 subjects were eligible for analysis (mean ± SD age 66.7 ± 7.8 years; mean ± SD body mass index 30.1 ± 5.8 kg/m2; 52% women). Radiographic OA in either knee (adjusted odds ratio [ORadj] 0.90 [95% confidence interval (95% CI) 0.63–1.30]; P = 0.587) was not associated with incident widespread pain. Baseline bilateral consistent frequent knee pain (ORadj 2.35 [95% CI 1.37–4.03]), bilateral symptomatic OA (ORadj 2.11 [95% CI 1.04–4.24]), and knee pain severity (worst knee) (ORadj 1.11 [95% CI 1.05–1.17]; P < 0.001) were significantly associated with incident widespread pain.ConclusionConsistent frequent knee pain, symptomatic OA, and knee pain severity increased the risk of developing widespread pain, independently of structural pathology. These results suggest that knee pain, and not structural pathology, contributes to the onset of widespread pain.
Hierarchical switching for active disturbance attenuation with fine controller tuning
Authors: Battistelli Giorgio , Selvi Daniela , Tesi Alberto 
Published: September 2016

SummaryIn this paper, a novel adaptive disturbance attenuation algorithm is proposed combining switching and tuning. A two‐level hierarchical switching logic is developed, which first selects in a short time the potentially best controller among a finite pre‐designed family and then performs a local refinement of its attenuation capability. Thanks to the controller fine tuning, the proposed technique is able to provide a substantial performance improvement in terms of attenuation level as compared with a pure adaptive switching control scheme; at the same time, it retains the positive features of switching‐based approaches, in particular, concerning the possibility of rapidly achieving a satisfactory behavior. Further, an arbitrary attenuation level is ensured in the presence of particular classes of disturbances and provided that it is compatible with robust stability requirement. Simulation results are shown to underline the potential of the approach as a solution to the problem. Copyright © 2016 John Wiley & Sons, Ltd.
From Polyacrylonitrile, its Solutions, and Filaments to Carbon Fibers II. Spinning PAN‐Precursors and their Thermal Treatment
Authors: Kulichikhin V. G. , Skvortsov I. Yu. , Mironova M. I. , Ozerin A. N. , Kurkin T. S. , Berkovich A. K. , Frenkin E. I. , Malkin A. Ya. 
Published: September 2016

AbstractBased on the results of Part 1 of this work, we have chosen acrylonitrile copolymers for preparing dopes in dimethyl sulfoxide (DMSO). Modeling the spinning process in static conditions was carried out by following the evolution of the interaction between a drop of solution and precipitant. In addition, the diffusion zone was controlled by the laser‐interference method. Fibers were spun on a laboratory stand. It was found that the optimal ratio of DMSO to water in a coagulation bath was 85/15. The analysis of the structure of different fibers (including fibers with carbon nanotubes) demonstrated the superposition of crystalline phase and orientation‐disordered mesophase. The evolution of this structure could provide the answer to the question of which structure of “white” fibers is best for obtaining high‐quality “black” fibers. Measurement of the structure and mechanical properties of fibers allowed us to optimize the technology of thermal treatment of fibers including the intensity of heat output in the stages of thermal‐oxidative stabilization and carbonization as well as the strain characteristics and applied tension. Model carbon fibers have a satisfactory complex of mechanical properties. We aimed to choose a set of experimental approaches as a proper way to produce high‐strength carbon fibers.
Thieno[3,4‐c]pyrrole‐4,6‐dione‐3,4‐difluorothiophene Polymer Acceptors for Efficient All‐Polymer Bulk Heterojunction Solar Cells
Authors: Liu Shengjian , Kan Zhipeng , Thomas Simil , Cruciani Federico , Brédas Jean‐Luc , Beaujuge Pierre M. 
Published: September 2016

AbstractBranched‐alkyl‐substituted poly(thieno[3,4‐c]pyrrole‐4,6‐dione‐alt‐3,4‐difluorothiophene) (PTPD[2F]T) can be used as a polymer acceptor in bulk heterojunction (BHJ) solar cells with a low‐band‐gap polymer donor (PCE10) commonly used with fullerenes. The “all‐polymer” BHJ devices made with PTPD[2F]T achieve efficiencies of up to 4.4 %. While, to date, most efficient polymer acceptors are based on perylenediimide or naphthalenediimide motifs, our study of PTPD[2F]T polymers shows that linear, all‐thiophene systems with adequately substituted main chains can also be conducive to efficient BHJ solar cells with polymer donors.
Total Synthesis of Aspergillomarasmine A and Related Compounds: A Sulfamidate Approach Enables Exploration of Structure–Activity Relationships
Authors: Albu Silvia A. , Koteva Kalinka , King Andrew M. , Al‐Karmi Salma , Wright Gerard D. , Capretta Alfredo 
Published: September 2016

AbstractThe fungal secondary metabolite aspergillomarasmine A (AMA) has recently been identified as an inhibitor of metallo‐β‐lactamases NDM‐1 and VIM‐2. Described herein is an efficient and practical route to AMA and its related compounds by a sulfamidate approach. In addition, a series of derivatives has been prepared and tested for biological activity in an effort to explore preliminary structure activity relationships. While it was determined that natural LLL isomer of AMA remains the most effective inactivator of NDM‐1 enzyme activity both in vitro and in cells, the structure is highly tolerant of the changes in the stereochemistry at positions 3, 6, and 9.
Tuning Excited‐State Reactivity by Proton‐Coupled Electron Transfer
Authors: Li Han , Zhang Ming‐Tian 
Published: September 2016

AbstractThe reactivity, and even reaction pathway, of excited states can be tuned by proton‐coupled electron transfer (PCET). The triplet state of benzophenone functionalized with a Brønsted acid (3*BP‐COOH) showed a more powerful oxidation capability over the simple triplet state of benzophenone (3*BP). 3*BP‐COOH could remove an electron from benzene at the rate of 8.0×105 m−1 s−1, in contrast to the reactivity of 3*BP which was inactive towards benzene oxidation. The origin of this great enhancement on the ability of the excited states to remove electrons from substrates is attributed to the intramolecular Brønsted acid, which enables the reductive quenching of 3*BP by concerted electron–proton transfer.
Probing Low‐Copy‐Number Proteins in a Single Living Cell
Authors: Liu Jia , Yin Danyang , Wang Shuangshou , Chen Hong‐Yuan , Liu Zhen 
Published: September 2016

AbstractSingle‐cell analysis techniques are essential for understanding the microheterogeneity and functions of cells. Low‐copy‐number proteins play important roles in cell functioning, but their measurement in single cells remains challenging. Herein, we report an approach, called plasmonic immunosandwich assay (PISA), for probing low‐copy‐number proteins in single cells. This approach combined in vivo immunoaffinity extraction and plasmon‐enhanced Raman scattering (PERS). Target proteins were specifically extracted from the cells by microprobes modified with monoclonal antibody or molecularly‐imprinted polymer (MIP), followed by labeling with Raman‐active nanotags. The PERS detection, with Raman intensity enhanced by 9 orders of magnitude, provided ultrasensitive detection at the single‐molecule level. Using this approach, we found that alkaline phosphatase and survivin were expressed in distinct levels in cancer and normal cells, and that extended culture passage resulted in reduced expression of survivin. We further developed acupuncture needle‐based PISA for probing low‐copy‐number proteins in living bodies.
Fortschritte bei der Ras‐Inhibition aus medizinisch‐chemischer Perspektive
Authors: Sautier Brice , Nising Carl F. , Wortmann Lars 
Published: September 2016

AbstractRas‐Mutanten zählen wegen ihres häufigen Auftretens bei vielen menschlichen Krebsarten und ihrer geringen Adressierbarkeit durch Wirkstoffe (niedrige “druggability”) derzeit zu den gesuchtesten (und anspruchsvollsten) onkologischen Targets. Hierdurch erklären sich die andauernden Forschungsbemühungen auf diesem Gebiet; mittlerweile haben sich die ersten Erfolge eingestellt, was wieder Anlass zu Optimismus gibt, Ras‐Inhibitoren zu entdecken. Dieser Kurzaufsatz diskutiert die aktuellen Fortschritte auf dem Weg zu irreversiblen Inhibitoren und stellt neue Ansätze zur Identifikation von Inhibitoren der Ras‐Effektor‐Interaktion vor, die infolge des momentanen Fokus auf direkter Ras‐Inhibition weniger Beachtung finden. Die Bewertung erfolgt dabei aus einer medizinalchemischen Perspektive.
Polythiophene with ionophore substituent in the side chain
Authors: Kadac Kornelia , Olewnik‐Kruszkowska Ewa , Nowaczyk Jacek 
Published: September 2016

ABSTRACTThe article presents the method of the synthesis of sulfonated polythiophene derivative (PTMBSA) in aqueous medium by means of emulsion polymerization. The method applies potassium peroxydisulfate as initiator and sodium dodecyl sulfate as the surfactant. The structure and physicochemical properties have been analyzed. Resulting polymers were characterized via Fourier transform infrared spectroscopy, X‐ray diffraction (XRD), thermogravimetric analysis, UV‐VIS, and electrochemical methods (e.g., cyclic voltammetric, current‐voltage characteristics, doping processes). Resulting polymer revealed mixed electronic and ionic conductivity having solid state maximum conductivity σ = 5.061 μS m−1. It is four orders of magnitude higher than this of pristine polythiophene obtained by similar way. Presented results show that tested polymers are interesting and seem to be promising material for organic electronic applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44372.