bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of aerosol optical properties above clouds between POLDER and AeroCom models over the South East Atlantic Ocean during the fire season
Authors: Peers F. , Bellouin N. , Waquet F. , Ducos F. , Goloub P. , Mollard J. , Myhre G. , Skeie R. B. , Takemura T. , Tanré D. , Thieuleux F. , Zhang K.
Published: April 2016

Aerosol properties above clouds have been retrieved over the South East Atlantic Ocean during the fire season 2006 using satellite observations from POLDER (Polarization and Directionality of Earth Reflectances). From June to October, POLDER has observed a mean Above‐Cloud Aerosol Optical Thickness (ACAOT) of 0.28 and a mean Above‐Clouds Single Scattering Albedo (ACSSA) of 0.87 at 550 nm. These results have been used to evaluate the simulation of aerosols above clouds in five Aerosol Comparisons between Observations and Models (Goddard Chemistry Aerosol Radiation and Transport (GOCART), Hadley Centre Global Environmental Model 3 (HadGEM3), European Centre Hamburg Model 5‐Hamburg Aerosol Module 2 (ECHAM5‐HAM2), Oslo‐Chemical Transport Model 2 (OsloCTM2), and Spectral Radiation‐Transport Model for Aerosol Species (SPRINTARS)). Most models do not reproduce the observed large aerosol load episodes. The comparison highlights the importance of the injection height and the vertical transport parameterizations to simulate the large ACAOT observed by POLDER. Furthermore, POLDER ACSSA is best reproduced by models with a high imaginary part of black carbon refractive index, in accordance with recent recommendations.
Lidar surveys reveal eruptive volumes and rates at Etna, 2007–2010
Authors: Behncke Boris , Fornaciai Alessandro , Neri Marco , Favalli Massimiliano , Ganci Gaetana , Mazzarini Francesco
Published: April 2016

The quantification of eruptive activity represents one major challenge in volcanology. Digital comparison of lidar‐based elevation models of Etna (Italy) was made to quantify the volumes of volcanics emitted in 2007–2010. During this period, Etna produced several summit paroxysms followed by a flank eruption. We integrated the total volume difference resulting from the subtraction of the 2007 and 2010 digital elevation models with volumes of eruptive products based on field and aerial surveys to attribute volumes with hitherto unrealized precision to poorly constrained eruptions. The total erupted volume of 2007–2010 is >86 × 106 m3, most (~74 × 106 m3) of which is made up by the lava flows of the 2008–2009 flank eruption. The survey also reveals the high lava volume (5.73 × 106 m3) and average eruption rate (~400 m3 s−1) of the 10 May 2008 paroxysm, whose flow front stopped 6.2 km from the vent, not far from the town of Zafferana Etnea.
Three‐dimensional full‐kinetic simulation of the solar wind interaction with a vertical dipolar lunar magnetic anomaly
Authors: Deca Jan , Divin Andrey , Wang Xu , Lembège Bertrand , Markidis Stefano , Horányi Mihály , Lapenta Giovanni
Published: April 2016

A detailed understanding of the solar wind interaction with lunar magnetic anomalies (LMAs) is essential to identify its implications for lunar exploration and to enhance our physical understanding of the particle dynamics in a magnetized plasma. We present the first three‐dimensional full‐kinetic electromagnetic simulation case study of the solar wind interaction with a vertical dipole, resembling a medium‐size LMA. In contrast to a horizontal dipole, we show that a vertical dipole twists its field lines and cannot form a minimagnetosphere. Instead, it creates a ring‐shaped weathering pattern and reflects up to 21% (four times more as compared to the horizontal case) of the incoming solar wind ions electrostatically through the normal electric field formed above the electron shielding region surrounding the cusp. This work delivers a vital piece to fully comprehend and interpret lunar observations, as we find the amount of reflected ions to be a tracer for the underlying field structure.
Decrease of aliphatic CHs from diatoms by in situ heating infrared microspectroscopy
Authors: Alipour Leila , Nakashima Satoru
Published: April 2016

In situ heating IR microspectroscopy at 260–300°C under air and N2 conditions has been conducted on diatom frustules to examine aliphatic CH losses during heating, simulating their changes with burial‐diagenesis. Assuming a reaction model made up of two first‐order kinetic relations, reaction rate constants k1 and k2 and activation energies (Ea) were evaluated for aliphatic CHs. The rate constants for loss of aliphatic CHs of diatom frustules under air and N2 flow are much larger, with much smaller activation energies (57–109 kJ/mol: air; 14–44 kJ/mol: N2), than those for conventional hydrocarbon generation reactions from kerogens (170–370 kJ/mol) studied at higher temperatures (350–450°C). The CH decrease rates are somewhat different from the amide I decrease (protein degradation) rates. The obtained results suggest that organic transformation reactions including degradation of aliphatic CHs inside the diatom silica frustules might be quite different from those of kerogens separated from the biological structures.
Determining groundwater Ra end‐member values for the estimation of the magnitude of submarine groundwater discharge using Ra isotope tracers
Authors: Cho Hyung‐Mi , Kim Guebuem
Published: April 2016

Radium isotopes (228Ra and 226Ra) are excellent tracers of submarine groundwater discharge (SGD). To estimate SGD magnitudes, information on the end‐member values of Ra concentrations in groundwater is critical; however, the distribution characteristics of Ra in coastal aquifers are poorly understood. In this study, we show that Ra concentrations in coastal groundwater are primarily dependent on salinity based on the data (n > 500) obtained from global coastal aquifers, although previous end‐member calculations averaged all Ra concentrations without considering salinity. If we assume that SGD is composed mainly of seawater infiltrating the aquifer, previous estimates of SGD for the Atlantic Ocean and the global ocean were overestimated twofold to threefold. This may be similar for other applications using different Ra isotopes. Our study highlights that the end‐members of Ra isotopes in groundwater should be carefully considered when estimating SGD using Ra isotope mass balances in the ocean.
Solar cycle variations of thermospheric composition at the solstices
Authors: Qian Liying , Burns Alan G. , Solomon Stanley C. , Wang Wenbin , Zhang Yongliang
Published: April 2016

We examine the solar cycle variability of thermospheric composition (O/N2) at the solstices. Our observational and modeling studies show that the summer‐to‐winter latitudinal gradient of O/N2 is small at solar minimum but large at solar maximum; O/N2 is larger at solar maximum than at solar minimum on a global‐mean basis; there is a seasonal asymmetry in the solar cycle variability of O/N2, with large solar cycle variations in the winter hemisphere and small solar cycle variations in the summer hemisphere. Model analysis reveals that vertical winds decrease the temperature‐driven solar cycle variability in the vertical gradient of O/N2 in the summer hemisphere but increase it in the winter hemisphere; consequently, the vertical gradient of O/N2 does not change much in the summer hemisphere over a solar cycle, but it increases greatly from solar minimum to solar maximum in the winter hemisphere; this seasonal asymmetry in the solar cycle variability in the vertical gradient of O/N2 causes a seasonal asymmetry in the vertical advection of O/N2, with small solar cycle variability in the summer hemisphere and large variability in the winter hemisphere, which in turn drives the observed seasonal asymmetry in the solar cycle variability of O/N2. Since the equatorial ionization anomaly suppresses upwelling in the summer hemisphere and strengthens downwelling in the winter hemisphere through plasma‐neutral collisional heating and ion drag, locations and relative magnitudes of the equatorial ionization anomaly crests and their solar cycle variabilities can significantly impact the summer‐to‐winter gradients of O/N2 and their solar cycle variability.
Dayside cosmic noise absorption at the equatorward boundary of auroral oval as observed from Maitri, Antarctica (L = 5; CGM 62.45°S, 55.45°E)
Authors: Behera Jayanta K. , Sinha Ashwini K. , Vichare Geeta , Kozyreva Olga , Rawat Rahul , Dhar Ajay
Published: April 2016

On 02 April 2011, a couple of cosmic noise absorption (CNA) events were detected at Maitri, Antarctica (L = 5; CGM 63.14°S, 53.69°E) confining to nighttime and daytime. One of the two events that occurred during night hours was caused due to auroral substorm onset. The current study focuses on the later CNA event, which was recorded during daytime (10:00–13:00 magnetic local time (MLT), MLT = UT‐1, at Maitri, Antarctica). We refer to this CNA event as dayside CNA (DCNA) event. Absence of westward electrojet during DCNA confirms its dissimilarity from auroral substorm absorption events. A comparison has been made between the DCNA event of 02 April 2011 with that of 14 July 2011, a day with substorm activity when Maitri is in dayside but without DCNA event. The comparison has been made in the light of interplanetary conditions, imaging riometer data, ground magnetic signatures, GOES electron flux density, and associated pulsations. The study shows that stronger prolonged eastward interplanetary electric field favors the occurrence of DCNA event. It is concluded that DCNA event is due to the gradient curvature drift of trapped nonrelativistic electrons in the equatorial plane. Estimated energy of trapped electrons using azimuthal drift time for a set of ground stations within the auroral oval confirms the enhancement in electron fluxes in the same energy band as recorded by geostationary satellites GOES 13 and GOES 15. The reason for precipitation of electrons is expected to be the loss cone scattering caused by wave‐particle interaction triggered by ULF waves.
Impact of the interaction between the quasi‐2 day wave and tides on the ionosphere and thermosphere
Authors: Yue Jia , Wang Wenbin , Ruan Haibing , Chang Loren C. , Lei Jiuhou
Published: April 2016

The quasi‐2 day wave (QTDW) can effectively interact with atmospheric tides in the mesosphere and lower thermosphere. We study the effect of this QTDW‐tidal interaction on the ionosphere and thermosphere using the thermosphere‐ionosphere‐mesosphere electrodynamics general circulation model. This interaction reduces the amplitude of the migrating diurnal tide in the lower thermosphere by ~10 m/s in neutral winds and also generates sum and difference secondary waves in the lower thermosphere and E region ionosphere. As a result of the changed migrating diurnal tide and sum/difference secondary wave, vertical ion drift varies with local time at different longitudes by ~5 m/s. In addition, the changed migrating diurnal tide also modulates the thermospheric composition (O/N2). During a QTDW event, the ionosphere F2 region peak electron density (NmF2) is reduced due to the mixing effect of the QTDW dissipation; NmF2 also shows changes in local time variation due to the QTDW‐tidal interaction. The sum and difference secondary waves can cause additional oscillations in vertical ion drift and ionospheric electron densities. The QTDW‐tidal interaction is another mechanism by which the QTDW impacts the ionosphere and thermosphere, along with other mechanisms: QTDW modulation of the E region wind dynamo with a period of quasi‐2 days and QTDW dissipation induced mixing in the thermosphere.
Characterization of the Climate Absolute Radiance and Refractivity Observatory (CLARREO) ability to serve as an infrared satellite intercalibration reference
Authors: Tobin David , Holz Robert , Nagle Fred , Revercomb Henry
Published: April 2016

Climate Absolute Radiance and Refractivity Observatory (CLARREO) is a future mission employing an infrared spectrometer with unprecedented calibration accuracy and the ability to assess its calibration on‐orbit using a novel verification system. Utilizing this capability for satellite intercalibration is a primary objective of the mission. This paper presents a new infrared intercalibration methodology that minimizes the intercalibration uncertainties and provides uncertainty estimates resulting from the scene variability and instrument noise. Results of a simulation study to characterize realistic spatial and temporal matching differences for simultaneous nadir overpasses (SNOs) of CLARREO and existing hyperspectral sounders are presented. This study, along with experience with intercalibration of real data, finds that intercalibration uncertainties are minimized when the SNOs are not screened for sky conditions but instead weighted based on the observed scene variability. Intercalibration performance is investigated for a 90° polar orbit mission and for a Pathfinder mission on the International Space Station, for various potential CLARREO footprint sizes, and as a function of mission length, scene brightness temperature, and wavelength. The results are encouraging and suggest that biases between CLARREO and sounder observations can be determined with low uncertainty and with high time frequency during a CLARREO mission. For example, the simulations suggest that a CLARREO footprint of 50 to 100 km in diameter is optimal for intercalibration, and that the 3 sigma intercalibration uncertainty is less than 0.1 K for channels at infrared window wavelengths using 2 months of accumulated SNOs, and for more absorbing channels with less scene variability the uncertainties are less than 50 mK.
Creating Memories for False Autobiographical Events in Childhood: A Systematic Review
Authors: Brewin Chris R. , Andrews Bernice
Published: April 2016

Using a framework that distinguishes autobiographical belief, recollective experience, and confidence in memory, we review three major paradigms used to suggest false childhood events to adults: imagination inflation, false feedback and memory implantation. Imagination inflation and false feedback studies increase the belief that a suggested event occurred by a small amount such that events are still thought unlikely to have happened. In memory implantation studies, some recollective experience for the suggested events is induced on average in 47% of participants, but only in 15% are these experiences likely to be rated as full memories. We conclude that susceptibility to false memories of childhood events appears more limited than has been suggested. The data emphasise the complex judgements involved in distinguishing real from imaginary recollections and caution against accepting investigator‐based ratings as necessarily corresponding to participants' self‐reports. Recommendations are made for presenting the results of these studies in courtroom settings. © 2016 The Authors Applied Cognitive Psychology Published by John Wiley & Sons Ltd.
Cognitive Biases in Visual Pilots' Weather‐Related Decision Making
Authors: Walmsley Stephen , Gilbey Andrew
Published: April 2016

Flights into deteriorating weather conditions are a significant cause of fatalities in general aviation accidents. This study investigated whether three common cognitive heuristics (anchoring and adjustment, confirmation, outcome) could lead to cognitive biases that might adversely affect pilots' weather‐related decision making. Study 1 found that weather reports obtained before a flight affected how pilots interpreted weather cues during flights (anchoring and adjustment). Study 2 found no evidence that pilots favoured disconfirmatory evidence over confirmatory evidence when deciding which environmental cues were most useful in deciding whether to continue a flight (confirmation). Study 3 found that pilots interpreted the decisions of pilots who flew into deteriorating weather conditions more favourably when the outcome was positive than when it was negative (outcome). These findings suggest that use of these three cognitive heuristics may lead to pilots continuing to fly into deteriorating weather conditions when the safer option is to divert or turn back. Copyright © 2016 John Wiley & Sons, Ltd.
Periodic Fever, Aphthosis, Pharyngitis, and Adenitis Syndrome: Analysis of Patients From Two Geographic Areas
Authors: Batu Ezgi D. , Kara Eroğlu Fehime , Tsoukas Paul , Hausmann Jonathan S. , Bilginer Yelda , Kenna Margaret A. , Licameli Greg R. , Fuhlbrigge Robert C. , Özen Seza , Dedeoğlu Fatma
Published: April 2016

Objective

Periodic fever, aphthosis, pharyngitis, and adenitis (PFAPA) syndrome is a periodic fever syndrome of childhood with an unknown etiology. Our aim was to compare the features between PFAPA syndrome patients from Turkey and those from the US, and patients with and without MEFV variants, and to test the performance of the Eurofever criteria in excluding other autoinflammatory disorders.

Methods

Seventy‐one children with PFAPA syndrome, followed in Hacettepe University, in Ankara, Turkey, and 60 patients at Boston Children's Hospital in the US were enrolled. MEFV gene‐variant analysis was performed in 56 patients with Sanger sequencing.

Results

In patients from Turkey, symptom onset was at a younger age, fever attacks were of shorter duration, and pharyngitis was more frequent, whereas adenitis, headache, and nausea/vomiting were less frequent during attacks, when compared to patients from the US (P < 0.05). More patients from the Turkish cohort were classified in the familial Mediterranean fever (FMF) group according to the Eurofever criteria than patients from the US (66.2% versus 10%; P < 0.001). Two patients were diagnosed with FMF after MEFV analysis. Twenty‐one patients (37.5%) had a single MEFV variant. No significant differences in phenotype were found between patients with and without MEFV variants.

Conclusion

The differences between patients from the Turkish and US cohorts may be due to epigenetic or environmental factors. In addition, the Eurofever FMF criteria may perform better in certain areas, if the weight of ethnic origin parameter or cutoff values were modified.
Reduced Aerobic Capacity and Quality of Life in Physically Inactive Patients With Systemic Lupus Erythematosus With Mild or Inactive Disease
Authors: Pinto Ana J. , Miyake Cintia N. H. , Benatti Fabiana B. , Silva Clovis A. , Sallum Adriana M. E. , Borba Eduardo , de Sá‐Pinto Ana L. , Bonfá Eloisa , Gualano Bruno
Published: April 2016

Objective

To compare aerobic capacity and health‐related quality of life (HRQOL) in physically inactive adult systemic lupus erythematosus (A‐SLE) and childhood‐onset systemic lupus erythematosus (C‐SLE) patients with mild/inactive disease versus healthy controls.

Methods

In a cross‐sectional study, 39 patients (C‐SLE: n = 18, ages 9–18 years; and A‐SLE: n = 21, ages 23–45 years) with inactive disease activity (Systemic Lupus Erythematosus Disease Activity Index ≤4) and low cumulative damage (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index ≤2) and 30 healthy controls (15 children and adolescents [C‐CTRL], 15 adults [A‐CTRL]) matched by physical inactivity, age, sex, and body mass index (BMI) were assessed for aerobic capacity and HRQOL.

Results

All participants were considered physically inactive according to physical activity guidelines. C‐SLE and A‐SLE patients showed lower
(95% CI confidence interval [95% CI] −10.5, −1.2 and −11.1, −3.8, respectively) and higher time‐to‐exhaustion when compared with C‐CTRL and A‐CTRL (95% CI −2.8, 0.1 and −3.9, −1.7, respectively). C‐SLE patients showed significantly lower scores in scholar functioning from the Pediatric Quality of Life Inventory questionnaire (P < 0.05) whereas A‐SLE patients showed lower scores in most domains of the Short Form 36 health survey questionnaire (physical function, role‐physical, bodily pain, general health, vitality, social function, and mental health) when compared with healthy controls (P < 0.05 for all).

Conclusion

Our study provides novel data suggesting that A‐SLE and C‐SLE patients with mild/inactive disease have impaired aerobic capacity and HRQOL when compared with controls matched by physical inactivity, age, sex, and BMI. These findings reinforce the recommendation of physical activity in SLE treatment.
Contrast‐Enhanced Ultrasound of the Carotid Artery in Patients With Large Vessel Vasculitis: Correlation With Positron Emission Tomography Findings
Authors: Germanò Giuseppe , Macchioni Pierluigi , Possemato Niccolò , Boiardi Luigi , Nicolini Alberto , Casali Massimiliano , Versari Annibale , Pipitone Nicolò , Salvarani Carlo
Published: April 2016

Objective

To assess the findings of contrast‐enhanced ultrasound (CEUS) of carotid arteries in patients with large vessel vasculitis (LVV) and to compare them with those observed using 18F‐fluorodeoxyglucose–positron emission tomography (18FDG‐PET).

Methods

A total of 31 consecutive patients with LVV (14 with Takayasu arteritis, 17 with giant cell arteritis with large vessel involvement) underwent both PET/computed tomography and carotid artery color Doppler ultrasound (CDUS) for a total of 35 combined assessments. Right carotid artery CEUS was performed after CDUS in all assessments. Kerr's criteria, a complete clinical examination, and acute phase reactants were simultaneously evaluated. The intensity of vascular uptake and vascularization of the carotid artery wall were compared.

Results

Ten 18F‐FDG/PET scans showed active vascular 18F‐FDG uptake (visual grade ≥2) in the right carotid artery. CEUS demonstrated severe vascularization (grade 2) within the right carotid artery wall in 12 examinations. The carotid CEUS vascularization grade significantly correlated with vascular 18F‐FDG uptake (P < 0.001) and maximum standardized uptake value (SUV) in the right carotid artery/mean SUV in the superior vena cava (P = 0.001). When active vascular 18F‐FDG uptake (≥2) was considered the gold standard for defining vascular inflammation, carotid CEUS had a sensitivity of 100% (95% confidence interval [95% CI] 65–100) and a specificity of 92% (95% CI 72–99). The positive likelihood ratio was 12.5 (95% CI 3.3–47.2). Severe vascularization at CEUS and active vascular 18F‐FDG uptake were significantly more frequent in active disease according to Kerr's criteria compared to inactive (P = 0.001 and P = 0.002, respectively).

Conclusion

Carotid CEUS vascularization grade and the grade of vascular inflammation on 18F‐FDG‐PET were correlated in patients with LVV.
Phosphorescent Polymeric Thermometers for In Vitro and In Vivo Temperature Sensing with Minimized Background Interference
Authors: Chen Zejing , Zhang Kenneth Yin , Tong Xiao , Liu Yahong , Hu Changyong , Liu Shujuan , Yu Qi , Zhao Qiang , Huang Wei
Published: April 2016

Temperature plays a crucial role in many biological processes. Accurate temperature determination is important for diagnosis and treatment of diseases. Autofluorescence is an unavoidable interference in luminescent bioimaging. Hence, a large amount of research works has been devoted to reducing background autofluorescence and improving signal‐to‐noise ratio (SNR) in biodetection. Herein, a dual‐emissive phosphorescent polymeric thermometer has been developed by incorporating two long‐lived phosphorescent iridium(III) complexes into an acrylamide‐based thermosensitive polymer. Upon increasing temperature, this polymer undergoes coil‐globule transition, which leads to a decrease in polarity of the microenvironment surrounding the iridium(III) complexes and hence brings about emission enhancement of both complexes. Owing to their different sensitivity to surrounding environment, the emission intensity ratio of the two complexes is correlated to the temperature. Thus, the polymer has been used for temperature determination in vitro and in vivo via ratiometric luminescence imaging. More importantly, by using the long‐lived phosphorescence of the polymer, temperature mapping in zebrafish has been demonstrated successfully with minimized autofluorescence interference and improved SNR via time‐resolved luminescence imaging. To the best of our knowledge, this is the first example to use photoluminescent thermometer for in vivo temperature sensing.
Guided Homing of Cells in Multi‐Photon Microfabricated Bioscaffolds
Authors: Skylar‐Scott Mark A. , Liu Man‐Chi , Wu Yuelong , Dixit Atray , Yanik Mehmet Fatih
Published: April 2016

Tissues contain exquisite vascular microstructures, and patterns of chemical cues for directing cell migration, homing, and differentiation for organ development and function. 3D microfabrication by multi‐photon photolithography is a flexible, high‐resolution tool for generating 3D bioscaffolds. However, the combined fabrication of scaffold microstructure simultaneously with patterning of cues to create both geometrically and chemically defined microenvironments remains to be demonstrated. This study presents a high‐speed method for micron‐resolution fabrication of scaffold microstructure and patterning of protein cues simultaneously using native scaffold materials. By the simultaneous microfabrication of arbitrary microvasculature geometries, and patterning selected regions of the microvasculature with the homing ligand P‐selectin, this study demonstrates adhesion, rolling, and selective homing of cells in defined 3D regions. This novel ability to generate high‐resolution geometries replete with patterned cues at high speed enables the construction of biomimetic microenvironments for complex 3D assays of cellular behavior.
A Low‐Temperature, Solution Processable Tin Oxide Electron‐Transporting Layer Prepared by the Dual‐Fuel Combustion Method for Efficient Perovskite Solar Cells
Authors: Liu Xiao , Tsai Kai‐Wei , Zhu Zonglong , Sun Ye , Chueh Chu‐Chen , Jen Alex K.‐Y.
Published: April 2016

Although tin oxide (SnO2) has been employed recently as an efficient electron‐transporter to realize highly efficient organometal halide perovskite solar cells (PVSCs), it is still quite challenging to apply it through facile solution‐based synthesis at low enough temperature (<150 °C) to be compatible with the roll‐to‐roll printing on polymer substrates. In this work, a dual‐fuel combustion method has been successfully adapted to modulate the exothermic characteristics and processing temperature (140 °C) of SnO2 to achieve homogeneous and crystalline thin film as efficient electron‐transporting layer for PVSCs. The fabricated SnO2 film not only has high transparency (from 350 nm to near‐infrared region) but also possesses good electron extraction ability, as evidenced by the efficient PL quenching in bilayered SnO2/CH3NH3PbI3 film. By passivating SnO2 surface with a C60‐containing self‐assembled monolayer (C60‐SAM), a high power conversion efficiency (PCEmax) of >15% with negligible hysteresis can be achieved in PVSC. This demonstrates the great potential of applying this dual‐fuel combustion process to improve processability and charge‐transporting properties of metal oxides for organic electronics applications.
Synthesis, Characterization, and Detailed Studies on Plasticized Poly(ethyl methacrylate): NH4I Polymer Electrolyte
Authors: Jibreel Umar M. , Bhattacharya B. , Singh Pramod K.
Published: April 2016

Polymer electrolyte films of poly(ethyl methacrylate) (PEMA) with ethylene carbonate (EC) as a plasticizer and ammonium iodide (NH4I) as an ion‐donating salt have been prepared using the solution‐cast technique. The electrical characterization of the films was performed by impedance spectroscopy. The highest obtained ionic conductivity at room temperature was 1.16 × 10−5 S/cm with the composition of PEMA: NH4I (60:40) + 10% EC. The ionic transference number of the mobile ions estimated by the dc polarization method, and the H+ ionic transference number was found to be ∼0.85, which revealed that the conductivity species are predominantly ions. Likewise, the micrographs of the films were analyzed under an optical microscope. In addition, the charge carrier density (n) of the individual films was calculated on the basis of the dielectric constant study.
Identification of a Novel Parallel β‐Strand Conformation within Molecular Monolayer of Amyloid Peptide
Authors: Liu Lei , Li Qiang , Zhang Shuai , Wang Xiaofeng , Hoffmann Søren Vrønning , Li Jingyuan , Liu Zheng , Besenbacher Flemming , Dong Mingdong
Published: April 2016

The differentiation of protein properties and biological functions arises from the variation in the primary and secondary structure. Specifically, in abnormal assemblies of protein, such as amyloid peptide, the secondary structure is closely correlated with the stable ensemble and the cytotoxicity. In this work, the early Aβ33‐42 aggregates forming the molecular monolayer at hydrophobic interface are investigated. The molecular monolayer of amyloid peptide Aβ33‐42 consisting of novel parallel β‐strand‐like structure is further revealed by means of a quantitative nanomechanical spectroscopy technique with force controlled in pico‐Newton range, combining with molecular dynamic simulation. The identified parallel β‐strand‐like structure of molecular monolayer is distinct from the antiparallel β‐strand structure of Aβ33‐42 amyloid fibril. This finding enriches the molecular structures of amyloid peptide aggregation, which could be closely related to the pathogenesis of amyloid disease.
Interplay between Cation and Charge Ordering in La1/3Sr2/3FeO3 Superlattices
Authors: Krick Alex L. , Lee Chan‐Woo , Sichel‐Tissot Rebecca J. , Rappe Andrew M. , May Steven J.
Published: April 2016

The electronic properties of digital superlattices are reported, which are cation‐ordered analogs of the perovskite La1/3Sr2/3FeO3, a material that undergoes a charge‐ordering transition. Superlattices of LaFeO3 (LFO), an antiferromagnetic insulator, and SrFeO3 (SFO), a conductor with a helical magnetic ground state, are fabricated via oxide molecular beam epitaxy. Three isocompositional superlattices with repeat structures of SSLSSL (S2), SSSLSL (S3), and SSSSLL (S4) (S = SFO, L = LFO) are studied with cation orderings along the [001] and [111] directions for experimental and computational work, respectively. The experimental superlattice structures are confirmed via synchrotron X‐ray diffraction and corresponding simulations of (00L) crystal truncation rods. The S2 and S3 superlattices are found to undergo an electronic phase transition as measured by a discontinuity in the temperature‐dependent resistivity similar to the random alloy, indicating that the superlattices do not behave as a simple combination of LFO and SFO. The charge‐ordering transition is not observed in the S4 sample. The electronic structure calculations using density functional theory, confirming the energetic favorability of charge ordering in the S2 and S3 structures compared to the S4 structure, are consistent with experimental trends.
Facile and Fine Polarity‐Tuning of Polymeric Semiconductors: The Effects of Nitrile Groups on Polymer–Polymer Blend Systems
Authors: Cho Jangwhan , Lee Sang Bong , Lee Han‐Koo , Kwon Soon‐Ki , Kim Yun‐Hi , Chung Dae Sung
Published: April 2016

Currently, the majority of high performance ambipolar polymer field effect transistors rely on the synthesis of donor–acceptor conjugated polymers with balanced hole/electron mobilities, whose polarity is predetermined during synthesis. However, further tuning of the device polarity is necessary in many applications, and a facile and fine polarity tuning with additional fabrication steps is necessary. To solve these issues, the utilization of polymer–polymer blends is recommended in which the electronic configuration and charge transport characteristics can be finely rationalized. A polymer–polymer blend system consisting of two different donor–acceptor polymeric semiconductors, namely PDPPTVT and PDPPCNTVT, is introduced with nearly identical chemical structures apart from the presence of a nitrile group. The nitrile group in PDPPCNTVT creates some important differences in terms of molecular orientation and surface energy in comparison to PDPPTVT. However, because of the chemical similarity, blend films consisting of these two polymers show outstanding homogeneous morphologies, enabling a facile and fine polarity tuning to be realized simply by changing the mixture ratio. A 1:1 blend ratio between PDPPTVT with hole mobility of ≈1 cm2 V−1 s−1 and PDPPCNTVT with electron mobility of ≈1 cm2 V−1 s−1 enables an almost balanced charge carrier mobility of ≈0.5 cm2 V−1 s−1 for both holes and electrons.
3D Vertically Aligned and Interconnected Porous Carbon Nanosheets as Sulfur Immobilizers for High Performance Lithium‐Sulfur Batteries
Authors: Rehman Sarish , Gu Xingxing , Khan Kishwar , Mahmood Nasir , Yang Wenlong , Huang Xiaoxiao , Guo Shaojun , Hou Yanglong
Published: April 2016

A unique nanostructure of 3D and vertically aligned and interconnected porous carbon nanosheets (3D‐VCNs) is demonstrated by a simple carbonization of agar. The key feature of 3D‐VCNs is that they possess numerous 3D channels with macrovoids and mesopores, leading to high surface area of 1750 m2 g−1, which play an important role in loading large amount of sulfur, while vertically aligned microporous carbon nanosheets act as the multilayered physical barrier against polysulfides anions and prevent their dissolution in the electrolyte due to strong adsorption during cycling process. As a result, the 3D hybrid (3D‐S‐VCNs) infiltered with 68.3 wt% sulfur exhibits a high and stable reversible capacity of 844 mAh g−1 at the current density of 837 mA g−1 with excellent Coulombic efficiency ≈100%, capacity retention of ≈80.3% over 300 cycles, and good rate ability (the reversible capacity of 738 mAh g−1 at the high current density of 3340 mA g−1). The present work highlights the vital role of the introduction of 3D carbon nanosheets with macrovoids and mesopores in enhancing the performance of LSBs.
Boron Nanoparticles for Room‐Temperature Hydrogen Generation from Water
Authors: Rohani Parham , Kim Seongbeom , Swihart Mark T.
Published: April 2016

Boron nanoparticles (BNPs) are of great interest for applications such as neutron capture therapy of cancer cells, hydrogen generation from water, and high energy density fuels. Boron is particularly interesting for chemical water splitting, because of its high gravimetric hydrogen generation potential of 277 g H2 per kg B. However, only a few studies of water splitting by reaction with boron are available, and those have used high temperature steam with external heating. Room‐temperature boron hydrolysis is of great interest from both scientific and practical perspectives. The studies presented here demonstrate that high purity amorphous BNPs can be oxidized by water to produce H2 at room temperature, without external energy input, in the presence of catalytic quantities of an alkali metal or alkali metal hydride. The BNPs are produced in a single step gas phase process via CO2 laser‐induced pyrolysis of mixtures of B2H6 and SF6. The BNPs are spherical with a primary particle diameter of 10–15 nm, narrow size distribution, and specific surface area exceeding 250 m2 g−1. This first demonstration of room‐temperature chemical splitting of liquid water using boron opens up exciting new possibilities for on‐demand hydrogen generation at high gravimetric capacity.
Impact of problem formulation on LNG process optimization
Authors: Austbø Bjørn , Gundersen Truls
Published: April 2016

The power consumption of a single mixed‐refrigerant process (PRICO®) for natural gas liquefaction was minimized using four different constraint formulations to handle the trade‐off between investment and operating costs. Aspen HYSYS® was used for process simulation, while a sequential quadratic programming algorithm (NLPQLP) was used for optimization. The results confirm that optimal utilization of the heat exchanger area is only obtained with a constraint based on a maximum heat exchanger conductance (UA). The minimum temperature difference constraint commonly used in process design gives a significant energy penalty as it is incapable of accounting for the distribution of driving forces with respect to temperature, the nonlinearity of the composite curves and the trade‐off between driving forces and cooling load. The results also indicate that the maximum UA constraint leads to increased complexity of the optimization problem, and that the success rate of the optimization method used therefore is reduced. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3598–3610, 2016
Countercurrent Droplet‐flow‐based mini extraction with pulsed feeding and without moving parts
Authors: Xu Cong , Jing Shan , Chu Yifeng
Published: April 2016

A countercurrent arrangement of immiscible liquid‐liquid mini contactors based on droplets is described in this article. Mini mixers without any moving parts were used as the contactors. The single stage mini mixer consists of a top and bottom mixing chamber. Both of the mixing chambers have two recirculating channels on either side. In these mini mixers, a liquid was broken up into droplets that dispersed into other continuously flowing liquid, consequently achieving a mass transfer between the two liquids. To realize the countercurrent arrangement, the two liquids were alternately fed into the system from opposite ends by compressed air according to a periodic program. One period consists of the following stages: organic phase feeding stage, droplet aggregation stage I, aqueous phase feeding stage, and droplet aggregation stage II. This continuous countercurrent arrangement is without the defects of continuous countercurrent arrangements based on laminar flows and multiple‐stage countercurrent arrangements based on droplets. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3685–3698, 2016
On thermodynamic separation efficiency: Adsorption processes
Authors: Lively Ryan P. , Realff Matthew J.
Published: April 2016

A simplified thermodynamic analysis of adsorption processes in temperature swing adsorption (TSA) and pressure swing adsorption (PSA) modes as a function of adsorbate concentration and the adsorbent–adsorbate interaction strength is presented in this article. The thermodynamic separation efficiency of a TSA process is optimal at dilute feed conditions, and becomes more thermodynamically efficient with increasing adsorbate affinity even though the energy of separation increases. The adsorption process is spontaneous, and for a strong isotherm, the energy required to reverse the adsorption is nearly independent of the adsorbate concentration as adsorbate loading in nearly‐saturated materials is essentially constant with feed concentration. PSA units are efficient thermodynamically and the efficiency increases with the concentration of the desired adsorbate. This thermodynamic treatment has implications for separation processes that address carbon emissions. TSA systems operate more efficiently (thermodynamically) in the “air capture” case because they apply work to the concentrated product rather than the dilute feed. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3699–3705, 2016
Metal‐Free Indeno[2,1‐b]thiophene‐Based Sensitizers for Dye‐Sensitized Solar Cells
Authors: Liang Chia‐Jung , Lin Yu‐Ju , Yen Yung‐Sheng , Lin Jiann T. , Yeh Ming‐Chang P.
Published: April 2016

A series of indeno[2,1‐b]thiophene‐containing organic dyes (IDT1–IDT5) have been synthesized, and their UV/Vis spectra extend beyond 700 nm. These dyes were employed as sensitizers for dye‐sensitized solar cells (DSSCs). Among them, dyes IDT3–IDT5 with a thiophene unit conjugated with an anchor have better light harvesting ability and higher JSC values. Dye aggregation contributes substantially to the photocurrent in the near infrared region. The dye IDT5, with chenodeoxycholic acid (CDCA) as the co‐adsorbent, has the highest power conversion efficiency (5.06 %) under AM 1.5G simulated sunlight irradiation, which is 68 % of the standard device based on N719 dye.
Rapid and Efficient Cascade Synthesis of 2‐Amino‐4(3 H)‐quinazolinones over an In Situ‐Generated Heterogeneous CuCO3–K2CO3 Nanocomposite
Authors: Thakur Maheshwar S. , Nayal Onkar S. , Bhatt Vinod , Sharma Sushila , Kumar Neeraj
Published: April 2016

A green, recyclable, in situ‐generated, heterogeneous CuCO3–K2CO3 nanocomposite‐catalysed cascade reaction between 2‐halobenzoic acids and guanidines is described for the synthesis of 2‐amino‐4(3H)‐quinazolinones. The reaction is rapid and proceeds efficiently in air without the addition of a ligand or additive. This protocol is equally applicable to amidines for the synthesis of 2‐alkyl‐ and 2‐phenyl‐4(3H)‐quinazolinones.
One for all and all for one: Linear regression from the mass of individual bones to assess human skeletal mass completeness
Authors: Gonçalves David , d'Oliveira Coelho João , Acosta Maria A. , Coelho Catarina , Curate Francisco , Ferreira Maria Teresa , Gouveia Márcia , Makhoul Calil , Pinto Débora , Oliveira‐Santos Inês , Vassalo Ana R. , Navega David , Cunha Eugénia
Published: April 2016

Objectives

Complete and accurate human skeletal inventory is seldom possible in archaeological and forensic cases involving severe fragmentation. In such cases, skeletal mass comparisons with published references may be used as an alternative to assess skeletal completeness but they are too general for a case‐by‐case routine analysis. The objective is to solve this issue by creating linear regression equations to estimate the total mass of a skeleton based on the mass of individual bones.

Materials and Methods

Total adult skeletal mass and individual mass of the clavicle, humerus, femur, patella, carpal, metacarpal, tarsal, and metatarsal bones were recorded in a sample of 60 skeletons from the 21st century identified skeletal collection (University of Coimbra). The sample included 32 females and 28 males with ages ranging from 31 to 96 years (mean = 76.4; sd = 14.8). Skeletal mass linear regression equations were calculated based on this sample.

Results

The mass of individual bones was successfully used to predict the approximate total mass of the adult skeleton. The femur, humerus, and second metacarpal were the best predictors of total skeletal mass with root mean squared errors ranging from 292.9 to 346.1 g.

Discussion

Linear regression was relatively successful at estimating adult skeletal mass. The non‐normal distribution of the sample in terms of mass may have reduced the predictive power of the equations. These results have clear impact for bioanthropology, especially forensic anthropology, since this method may provide better estimates of the completeness of the skeleton or the minimum number of individuals. Am J Phys Anthropol 160:427–432, 2016. © 2016 Wiley Periodicals, Inc.
Incisor ablation among the late upper paleolithic people of Tam Hang (Northern Laos): Social identity, mortuary practice, and oral health
Authors: Willman John C. , Shackelford Laura , Demeter Fabrice
Published: April 2016

Objectives

A detailed assessment of intentional incisor ablation among the Late Upper Paleolithic people of Tam Hang (northern Laos) was undertaken to understand how this cultural practice, in addition to age and sex, influenced an individual's inclusion in the mortuary context. The covariation of ablation status with occlusal variation and anterior dental pathology was addressed to study the implications of this cultural practice on oral health.

Materials and Methods

Sex, age, caries, antemortem tooth loss, and occlusal variation were assessed through standard osteological methods for 12 individuals. An observational protocol to identify intentional ablation was developed specifically for this sample.

Results

Four ablation states were identified that range from no ablation to the removal of two, three, or four lateral (I2) incisors. The timing of ablation was attributed to ritual extractions during early adolescence. Adult age‐at‐death was the strongest indicator of inclusion in the main burial context and a child burial was isolated from those of adults. Ablation status does not strongly influence inclusion in the mortuary context. Individuals lacking ablation tended to have a higher incidence of anterior caries, pathological tooth loss, incisor crowding, and canine rotation.

Conclusions

This study identifies the oldest case of intentional incisor ablation in Late Pleistocene Mainland Southeast Asia. We conclude that ablation does not always “compromise” the dentition; instead, it may have unintentional oral health benefits in some contexts. Am J Phys Anthropol 160:519–528, 2016. © 2016 Wiley Periodicals, Inc.
Monitoring Backbone Hydrogen‐Bond Formation in β‐Barrel Membrane Protein Folding
Authors: Raschle Thomas , Rios Flores Perla , Opitz Christian , Müller Daniel J. , Hiller Sebastian
Published: April 2016

β‐barrel membrane proteins are key components of the outer membrane of bacteria, mitochondria and chloroplasts. Their three‐dimensional structure is defined by a network of backbone hydrogen bonds between adjacent β‐strands. Here, we employ hydrogen–deuterium (H/D) exchange in combination with NMR spectroscopy and mass spectrometry to monitor backbone hydrogen bond formation during folding of the outer membrane protein X (OmpX) from E. coli in detergent micelles. Residue‐specific kinetics of interstrand hydrogen‐bond formation were found to be uniform in the entire β‐barrel and synchronized to formation of the tertiary structure. OmpX folding thus propagates via a long‐lived conformational ensemble state in which all backbone amide protons exchange with the solvent and engage in hydrogen bonds only transiently. Stable formation of the entire OmpX hydrogen bond network occurs downhill of the rate‐limiting transition state and thus appears cooperative on the overall folding time scale.
Grafting of Secondary Diolamides onto [P2W15V3O62]9− Generates Hybrid Heteropoly Acids
Authors: Lachkar David , Vilona Debora , Dumont Elise , Lelli Moreno , Lacôte Emmanuel
Published: April 2016

The Dawson tungstovanadate [P2W15V3O62]9− can be grafted to secondary diolamides. The electron‐withdrawing character of the polyanion increases the acidity of the amide proton, leading to an organo‐polyoxometalate, which can be used as a Brønsted organocatalyst. High‐field NMR and DFT modeling indicate that the amide proton stays on the nitrogen and that the exalted acidity derives from the interaction between the organic and inorganic parts of the organo‐polyoxometalate. The amide‐inserted vanadotungstates thus form a new family of (hybrid) heteropolyacids, offering new perspectives for the application of POM‐based catalysis in organic synthesis.
Stereoselective Synthesis of Tetrahydroindolizines through the Catalytic Formation of Pyridinium Ylides from Diazo Compounds
Authors: Day Jonathan , McKeever‐Abbas Ben , Dowden James
Published: April 2016

Commercially available iron(III) and copper(I) complexes catalyzed multicomponent cycloaddition reactions between diazo compounds, pyridines, and electrophilic alkenes to give alkaloid‐inspired tetrahydroindolizidines in high yield with high diastereoselectivity. Hitherto, the catalytic formation of versatile pyridinium ylides from metal carbenes has been poorly developed; the broad utility demonstrated herein sets the stage for the invention of further multicomponent reactions in future.
Transition‐Metal‐Free Synthesis of Homo‐ and Hetero‐1,2,4‐Triaryl Benzenes by an Unexpected Base‐Promoted Dearylative Pathway
Authors: Rehan Mohammad , Maity Sanjay , Morya Lalit Kumar , Pal Kaushik , Ghorai Prasanta
Published: April 2016

An unprecedented approach for the synthesis of homo‐ and hetero‐1,2,4‐triaryl benzenes has been developed using a simple base‐mediated reaction of either α‐aryl cinnamyl alcohols or α,γ‐di‐aryl propanones. The salient feature of this strategy involves the sequential hydride transfer, regiospecific condensation, regiospecific dearylation, and aromatization under metal‐free reaction conditions. The synthesis of unsymmetrically substituted triphenylenes by oxidative coupling of the synthesized 1,2,4‐triaryl benzenes has also been demonstrated.