bluuebunny/crossref_metadata_2025_split huggingface dataset:
Van Allen Probes observations of magnetic field dipolarization and its associated O+ flux variations in the inner magnetosphere at L < 6.6
Authors: Nosé M. , Keika K. , Kletzing C. A. , Spence H. E. , Smith C. W. , MacDowall R. J. , Reeves G. D. , Larsen B. A. , Mitchell D. G. 
Published: July 2016

AbstractWe investigate the magnetic field dipolarization in the inner magnetosphere and its associated ion flux variations, using the magnetic field and energetic ion flux data acquired by the Van Allen Probes. From a study of 74 events that appeared at L = 4.5–6.6 between 1 October 2012 and 31 October 2013, we reveal the following characteristics of the dipolarization in the inner magnetosphere: (1) its time scale is approximately 5 min; (2) it is accompanied by strong magnetic fluctuations that have a dominant frequency close to the O+ gyrofrequency; (3) ion fluxes at 20–50 keV are simultaneously enhanced with larger magnitudes for O+ than for H+; (4) after a few minutes of the dipolarization, the flux enhancement at 0.1–5 keV appears with a clear energy‐dispersion signature only for O+; and (5) the energy‐dispersed O+ flux enhancement appears in directions parallel or antiparallel to the magnetic field. From these characteristics, we discuss possible mechanisms that can provide selective acceleration to O+ ions at >20 keV. We conclude that O+ ions at L = 5.4–6.6 undergo nonadiabatic local acceleration caused by oscillating electric field associated with the magnetic fluctuations and/or adiabatic convective transport from the plasma sheet to the inner magnetosphere by the impulsive electric field. At L = 4.5–5.4, however, only the former acceleration is plausible. We also conclude that the field‐aligned energy‐dispersed O+ ions at 0.1–5 keV originate from the ionosphere and are extracted nearly simultaneously to the onset of the dipolarization.
Assessment of IRI and IRI‐Plas models over the African equatorial and low‐latitude region
Authors: Adebiyi S. J. , Adimula I. A. , Oladipo O. A. , Joshua B. W. 
Published: July 2016

AbstractA reliable ionospheric specification by empirical models is important to mitigate the effects of the ionosphere on the operations of satellite‐based positioning and navigation systems. This study evaluates the capability of the International Reference Ionosphere (IRI) and IRI extended to the plasmasphere (IRI‐Plas) models in predicting the total electron content (TEC) over stations located in the southern hemisphere of the African equatorial and low‐latitude region. TEC derived from Global Positioning System (GPS) measurements were compared with TEC predicted by both the IRI‐Plas 2015 model and the three topside options of the IRI 2012 model (i.e., NeQuick (NeQ), IRI 2001 corrected factor (IRI‐01 Corr), and the IRI 2001(IRI‐01)). Generally, the diurnal and the seasonal structures of modeled TEC follow quite well with the observed TEC in all the stations, although with some upward and downward offsets observed during the daytime and nighttime. The prediction errors of both models exhibit latitudinal variation and these showed seasonal trends. The values generally decrease with increase in latitude. The TEC data‐model divergence of both models is most significant at stations in the equatorial region during the daytime and nighttime. Conversely, both models demonstrate most pronounced convergence during the nighttime at stations outside the equatorial region. The IRI‐Plas model, in general, performed better in months and seasons when the three options of the IRI model underestimate TEC. Factors such as the height limitation of the IRI model, the inaccurate predictions of the bottomside and topside electron density profiles were used to explain the data‐model discrepancies.
Precipitation variability and response to changing climatic condition in the Yarlung Tsangpo River basin, China
Authors: Sang Yan‐Fang , Singh Vijay P. , Gong Tongliang , Xu Kang , Sun Fubao , Liu Changming , Liu Wenbin , Chen Ruizhi 
Published: July 2016

AbstractHydroclimatic process in the Yarlung Tsangpo River (YTR) basin, a sensitive area to climate change, is obviously changing during recent years, but there has limited understanding about it. In this study, we investigated the spatiotemporal variation of precipitation over last four decades in the basin and the impact thereon of the changing Indian summer monsoon at interannual and decadal time scales. All the precipitation series have similar scaling behavior, reflecting similar climatic regime throughout the basin. However, the effect of the Indian monsoon strengthens from the downstream to upstream, causing spatial variability in the seasonal distribution of precipitation, and on this basis, the YTR basin is roughly divided into three regions: east, middle, and west. Both the occurrence times and magnitude of precipitation extremes, ranging 25–50 mm/d, are exhibiting downward trends over the last four decades, which bodes well for water disaster controls in the basin. The Indian summer monsoon index, as an intensity indicator for the Indian summer monsoon, shows a positive relationship with the summer precipitation in the YTR basin. Periodic variability of the Indian monsoon determines the interannual nonstationary fluctuations of precipitation. Especially, the weakening effect of the Indian summer monsoon has caused an obvious decrease in precipitation over the rainy season after 1998. If the Indian summer monsoon keeps weakening, the precipitation would decrease and potentially water shortage would become more severe in the basin. Effective adaptation strategy should therefore be developed proactively to handle the unfavorable water situation, which is likely to occur in the future.
Biocultural research in global mental health: mapping idioms of distress onto blood pressure in a population survey
Authors: Sancilio Amelia , Eggerman Mark , Panter‐Brick Catherine 
Published: July 2016

AbstractObjectivesBiocultural research remains a challenge in the field of global mental health. We sought to test associations between blood pressure and idioms of distress in a population survey.MethodsWe drew on a randomly selected sample of 991 adults (498 men, 493 women) in Afghanistan, for whom physiological and psychosocial data were systematically collected. Assessment of mental health (Self‐Reported Questionnaire, Afghan Symptom Checklist) included conceptualizations of distress related to pressure (fishar), anxiety, and dysphoria, as well as dimensions of negative affect and aggression. We used principal component analysis to map survey responses to fishar, and multiple regressions to examine associations with systolic/diastolic blood pressure, controlling for age, body mass index, and wealth, and differentiating by gender, mental health, and medication.ResultsThe Afghan sample averaged 129/80 mmHg, with 27.14% of hypertensive individuals. SBP showed inverse associations with reports of low fishar (β = −4.58, P < .001) and high fishar (β = 6.90, P < .001), as did DPB with low fishar (β = −1.55, P < .001) and high fishar (β = 3.77, P < .001). Low and high fishar responses accounted for substantial proportions of SBP data variation (R2 = 20% and R2 = 24%), especially in adults on blood pressure medication (R2 = 58% and R2 = 49%).ConclusionsSubjective reports of fishar map onto physiological blood pressure more robustly than other conceptualizations of mental distress related to anxiety, dysphoria, negative affect, or aggression. Our results point to the utility of mapping biological and cultural measures of stress and distress, advancing biopsychosocial understandings of wellbeing in global mental health surveys.
Synthesis of Tetrazino‐tetrazine 1,3,6,8‐Tetraoxide (TTTO)
Authors: Klenov Michael S. , Guskov Alexey A. , Anikin Oleg V. , Churakov Aleksandr M. , Strelenko Yurii A. , Fedyanin Ivan V. , Lyssenko Konstantin A. , Tartakovsky Vladimir A. 
Published: July 2016

AbstractThis study presents the first synthesis and characterization of a new high energy compound [1,2,3,4]tetrazino[5,6‐e][1,2,3,4]tetrazine 1,3,6,8‐tetraoxide (TTTO). It was synthesized in ten steps from 2,2‐bis(tert‐butyl‐NNO‐azoxy)acetonitrile. The synthetic strategy was based on the sequential closure of two 1,2,3,4‐tetrazine 1,3‐dioxide rings by the generation of oxodiazonium ions and their intramolecular coupling with tert‐butyl‐NNO‐azoxy groups. The TTTO structure was confirmed by single‐crystal X‐ray.
Metabolic Glycoengineering with N‐Acyl Side Chain Modified Mannosamines
Authors: Wratil Paul R. , Horstkorte Rüdiger , Reutter Werner 
Published: July 2016

AbstractIn metabolic glycoengineering (MGE), cells or animals are treated with unnatural derivatives of monosaccharides. After entering the cytosol, these sugar analogues are metabolized and subsequently expressed on newly synthesized glycoconjugates. The feasibility of MGE was first discovered for sialylated glycans, by using N‐acyl‐modified mannosamines as precursor molecules for unnatural sialic acids. Prerequisite is the promiscuity of the enzymes of the Roseman–Warren biosynthetic pathway. These enzymes were shown to tolerate specific modifications of the N‐acyl side chain of mannosamine analogues, for example, elongation by one or more methylene groups (aliphatic modifications) or by insertion of reactive groups (bioorthogonal modifications). Unnatural sialic acids are incorporated into glycoconjugates of cells and organs. MGE has intriguing biological consequences for treated cells (aliphatic MGE) and offers the opportunity to visualize the topography and dynamics of sialylated glycans in vitro, ex vivo, and in vivo (bioorthogonal MGE).
New Structural Data Reveal the Motion of Carrier Proteins in Nonribosomal Peptide Synthesis
Authors: Kittilä Tiia , Mollo Aurelio , Charkoudian Louise K. , Cryle Max J. 
Published: July 2016

AbstractThe nonribosomal peptide synthetases (NRPSs) are one of the most promising resources for the production of new bioactive molecules. The mechanism of NRPS catalysis is based around sequential catalytic domains: these are organized into modules, where each module selects, modifies, and incorporates an amino acid into the growing peptide. The intermediates formed during NRPS catalysis are delivered between enzyme centers by peptidyl carrier protein (PCP) domains, which makes PCP interactions and movements crucial to NRPS mechanism. PCP movement has been linked to the domain alternation cycle of adenylation (A) domains, and recent complete NRPS module structures provide support for this hypothesis. However, it appears as though the A domain alternation alone is insufficient to account for the complete NRPS catalytic cycle and that the loaded state of the PCP must also play a role in choreographing catalysis in these complex and fascinating molecular machines.
Radial thermoelectric generator fabricated from n‐ and p‐type conducting polymers
Authors: Menon Akanksha K. , Meek Olivia , Eng Arnold J. , Yee Shannon K. 
Published: July 2016

ABSTRACTElectrically conducting polymers are attractive for thermoelectric generators (TEGs) because of their low thermal conductivity and solution processability. In this article, we report on the performance of a radial device made from n‐ and p‐type polymers printed on paper substrates. Our thermoelectric (TE) models predict an optimized geometry for a radial device that operates under natural convective cooling alone, and herein, we report on the fabrication and performance of this new organic TEG. We used poly(nickel‐1,1,2,2‐ethenetetrathiolate) blended with poly(vinylidene fluoride)/dimethyl sulfoxide as the n‐type material and poly(3,4‐ethylenedioxythiophene)/poly(styrene sulfonate) with Tellurium nanowires as the p‐type materials coated on paper to evaluate the TE performance. The radial TEG produced an open‐circuit voltage of 85 mV and a power density of 15 nW/cm2 under a 45‐K temperature difference. This proof of concept was the first demonstration of a polymer‐based radial TEG that accommodated a hot pipe as the heat source and did not require active cooling because of heat spreading. This is promising for scalable and low cost TE devices for self‐powered sensor networks. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44060.
PFG‐NMR measurement of self‐diffusion coefficients of long‐chain α‐olefins and their mixtures in semi‐crystalline polyethylene
Authors: Sun Jingyuan , Chen Meijuan , Wang Haotong , Jiang Binbo , Mattea Carlos , Stapf Siegfried , Wang Jingdai , Liao Zuwei , Yang Yongrong 
Published: July 2016

ABSTRACTThe self‐diffusion coefficients of C6–C16 long‐chain α‐olefins and their mixtures in semi‐crystalline polyethylene were measured through the pulsed field gradient nuclear magnetic resonance (PFG‐NMR). The effects of chain length, polyethylene (PE) type, and co‐monomer type in PE on the diffusion coefficients were investigated. Moreover, the influence of halohydrocarbon, cycloalkanes, and arene solvents on the diffusion coefficients of C12 α‐olefin in PE was characterized. The results have demonstrated that the diffusion coefficient of the single‐component α‐olefin in PE decreases exponentially with the increase of the carbon number of α‐olefin, and the crystallinity and crystal morphology of PE play a more important role than the co‐monomer type in determining the diffusion coefficients of α‐olefins. In addition, the apparent diffusion coefficients were used to represent the diffusion behaviors of the α‐olefin mixtures in PE. Owing to the presence of other hydrocarbon solvents, namely trichloromethane, cyclohexane, and benzene, the diffusion coefficients of C12 long‐chain α‐olefin in PE are significantly enhanced, and such promoting effect of the hydrocarbon solvents in polyolefin elastomer (POE) is much stronger than those in high‐density polyethylene (HDPE) and linear low‐density polyethylene (LLDPE). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44143.
Octakis(ethynyldimethylsiloxy) silsesquioxane: Synthesis and application in poly(silicane arylacetylene) resin
Authors: Bu Xiaojun , Zhou Yan , Li Chuan , Huang Farong 
Published: July 2016

ABSTRACTOctakis(ethynyldimethylsiloxy)silsesquioxane (OEMS) was first synthesized via hydrolysis condensation reaction between tetramethylammonium octaanion and ethynyldimethylchlorosilane, and characterized by FT‐IR, NMR, and GPC methods. A series of OEMS modified poly(silicane arylacetylene) resins (OEMS‐PSAs) were prepared from OEMS and poly(silicane arylacetylene) (PSA). TEM analysis of the OEMS‐PSAs confirms that the nano‐sized polyhedral oligomeric silsesquioxanes (POSS) are dispersed evenly in low content, but aggregated unregularly in high content in OEMS‐PSAs. The curing behavior of OEMS‐PSAs was studied with DSC and FT‐IR techniques. Nanoindentation test shows the incorporation of OEMS into PSA could decrease both of the elastic modulus and surface hardness of the PSA thermoset. The dielectric constants (ɛr) of the OEMS‐PSA thermosets approach to 2.1, depending on not only the content of POSS but also the dispersion of POSS. Furthermore, TGA results demonstrate the OEMS‐PSA thermosets possess the certain thermo‐oxidative resistance. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44158.
A Study of Different Doped Metal Cations on the Physicochemical Properties and Catalytic Activities of Ce20M1Ox (M=Zr, Cr, Mn, Fe, Co, Sn) Composite Oxides for Nitric Oxide Reduction by Carbon Monoxide
Authors: Deng Changshun , Li Min , Qian Junning , Hu Qun , Huang Meina , Lin Qingjin , Ruan Yongshun , Dong Lihui , Li Bin , Fan Minguang 
Published: July 2016

AbstractThis work is mainly focused on investigating the effects of different doped metal cations on the formation of Ce20M1Ox (M=Zr, Cr, Mn, Fe, Co, Sn) composite oxides and their physicochemical and catalytic properties for NO reduction by CO as a model reaction. The obtained samples were characterized by using N2 physisorption, X‐ray diffraction, laser Raman spectroscopy, UV/Vis diffuse reflectance spectroscopy, inductively coupled plasma atomic emission spectroscopy, X‐ray photoelectron spectroscopy, temperature‐programmed reduction by hydrogen and by oxygen (H2‐TPR and O2‐TPD), in situ diffuse reflectance infrared Fourier transform spectroscopy, and the NO+CO model reaction. The results imply that the introduction of Mx+ into the lattice of CeO2 increases the specific surface area and pore volume, especially for variable valence metal cations, and enhances the catalytic performance to a great extent. In this regard, increases in the oxygen vacancies, reduction properties, and chemisorbed O2− (and/or O−) species of these Ce20M1Ox composite oxides (M refers to variable valence metals) play significant roles in this reaction. Among the samples, Ce20Cr1Ox exhibited the best catalytic performance, mainly because it has the best reducibility and more chemisorbed oxygen, and significant reasons for these attributes may be closely related to favorable synergistic interactions of the vacancies and near‐surface Ce3+ and Cr3+. Finally, a possible reaction mechanism was tentatively proposed to understand the reactions.
An iterative approach to H−/H∞ Fault Detection Observer Design for Discrete‐Time Uncertain Systems
Authors: Huang Di , Duan Zhisheng , Hao Yuqing 
Published: July 2016

AbstractIn this paper, H−/H∞ multi‐objective fault detection observer design problem for linear discrete‐time systems is studied. Owing to the model inaccuracy in practical situations, system uncertainty is considered as well as the structure of the uncertainty. Sufficient conditions for the existence of the observers to guarantee the fault sensitivity and disturbance robustness in infinite frequency domain are presented. A new iterative linear matrix inequality (LMI) algorithm for the observers are proposed to obtain the solutions. In order to reduce the conservativeness, the observer design problem in finite frequency domain is also investigated. Simulation results illustrate the effectiveness of the proposed methods.
Simulating the 20 May 2013 Moore, Oklahoma tornado with a 100‐metre grid‐length NWP model
Authors: Hanley Kirsty E. , Barrett Andrew I. , Lean Humphrey W. 
Published: July 2016

AbstractSince 2013, the Met Office have run a 2.2 km horizontal gridlength version of the Unified Model (MetUM) as part of the National Oceanographic and Atmospheric Administration's Hazardous Weather Testbed Spring Forecasting Experiment. In this study, we perform high resolution MetUM simulations of the 20 May 2013 Oklahoma tornado outbreak at horizontal gridlengths between 2.2 km and 100 m. Here we present results showing that at 2.2 km gridlength the MetUM is able to simulate supercell‐like storms whereas at O(100 m) gridlength it is able to simulate realistic‐looking supercells with tornado‐like vortices. This opens up the opportunity for using such simulations to highlight areas of enhanced tornado risk ahead of time.
A review of sugarcane bagasse for second‐generation bioethanol and biopower production
Authors: Bezerra Tais Lacerda , Ragauskas Art J. 
Published: July 2016

AbstractSugarcane bagasse is a large‐volume agriculture residue that is generated on a ~540 million metric tons per year basis globally1,2 with the top‐three producing countries in Latin America being Brazil (~181 million metric ton yr−1),3 Mexico (ܾ15 million metric ton yr−1),4 and Colombia (ܾ7 million metric ton yr−1),5 respectively.6 Given sustainability concerns and the need to maximize the utilization of bioresources, the use of sugarcane bagasse is receiving significant attention in biorefining applications, as it is a promising resource for the conversion to biofuels and biopower. This review provides a comprehensive review of bagasse and its chemical constituents and on‐going research into its utilization as a feedstock for cellulosic ethanol and electricity generation. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd
Targeting HPV‐infected cervical cancer cells with PEGylated liposomes encapsulating siRNA and the role of siRNA complexation with polyethylenimine
Authors: Levine Rachel M. , Dinh Christina V. , Harris Michael A. , Kokkoli Efrosini 
Published: July 2016

AbstractThe greatest obstacle to clinical application of cancer gene therapy is lack of effective delivery tools. Gene delivery vehicles must protect against degradation, avoid immunogenic effects and prevent off target delivery which can cause harmful side effects. PEGylated liposomes have greatly improved tumor localization of small molecule drugs and are a promising tool for nucleic acid delivery as the polyethylene glycol (PEG) coating protects against immune recognition and blood clearance. In this study, small interfering RNA (siRNA) was fully encapsulated within PEGylated liposomes by complexing the siRNA with a cationic polymer, polyethyleneimine (PEI), before encapsulation. Formation methods and material compositions were then investigated for their effects on encapsulation. This technology was translated for protective delivery of siRNA designed for human papillomavirus (HPV) viral gene silencing and cervical cancer treatment. PEGylated liposomes encapsulating siRNA were functionalized with the AG86 targeting peptide‐amphiphile which binds to the α6β4 integrin, a cervical cancer biomarker. It was found that both targeting and polymer complexation before encapsulation were critical components to effective transfection.
Self‐Assembly of a Tripodal Triszwitterion Forms a pH‐Switchable Hydrogel that Can Reversibly Encapsulate Hydrophobic Guests in Water
Authors: Jana Poulami , Schmuck Carsten 
Published: July 2016

AbstractThe development of supramolecular smart materials, which exhibit physicochemical structural changes in response to external stimuli is of current interest for various applications. Herein, we have developed the novel tripodal triszwitterion 1, derived from a C3‐symmetric benzene‐1,3,5‐tricarboxamide (BTA) core, which forms a thermo‐reversible and pH‐switchable transparent hydrogel through intermolecular self‐complementary zwitterionic interactions at a neutral pH value. The hierarchical supramolecular self‐aggregation was fully analyzed by microscopy (AFM, field emission scanning electron microscopy (FESEM)), viscosity, dynamic light scattering (DLS), and rheology studies. Moreover, compound 1 enables to encapsulate hydrophobic guests, such as the dye Nile red in aqueous medium at pH 6, which makes it an interesting candidate for drug delivery and controlled release.
The role of dilute and semi‐dilute cellulose nanocrystal (CNC) suspensions on the rheology of carboxymethyl cellulose (CMC) solutions
Authors: Oguzlu Hale , Danumah Christophe , Boluk Yaman 
Published: July 2016

AbstractNon‐Newtonian flow behaviours of dilute and semi‐dilute carboxymethyl cellulose (CMC) solutions in the presence of spindle‐shaped cellulose nanocrystal particles (CNC) were investigated. Scanning transmission electron microscopy, dynamic light scattering, polarized optical microscopy, and turbidity measurements of CNC suspensions in CMC solutions were also carried out. Adding CNC particles only within the range of 0.33–2.0 m3/m3 into the dilute and semi‐dilute CMC polymer solutions increased the viscosities at low shear rates between 103–105 times. The flow curves of CNC suspensions in CMC polymer solutions turned highly non‐Newtonian, and their viscosities at high shear rates (> 103) still converged to the flow curves of CMC solutions. The viscosity increase comes from the nematic flocculation of CNC particles in the presence of a non‐adsorbing CMC polymer which results in CNC flocs with water entrapped pockets.