bluuebunny/crossref_metadata_2025 huggingface dataset:
Fast-cycling unit of root turnover in perennial herbaceous plants in a cold temperate ecosystem
Authors: Sun Kai , Luke McCormack M. , Li Le , Ma Zeqing , Guo Dali
Published: January 2016

Roots of perennial plants have both persistent portion and fast-cycling units represented by different levels of branching. In woody species, the distal nonwoody branch orders as a unit are born and die together relatively rapidly (within 1–2 years). However, whether the fast-cycling units also exist in perennial herbs is unknown. We monitored root demography of seven perennial herbs over two years in a cold temperate ecosystem and we classified the largest roots on the root collar or rhizome as basal roots and associated finer laterals as secondary, tertiary and quaternary roots. Parallel to woody plants in which distal root orders form a fast-cycling module, basal root and its finer laterals also represent a fast-cycling module in herbaceous plants. Within this module, basal roots had a lifespan of 0.5–2 years and represented 62–87% of total root biomass, thus dominating annual root turnover (60%–81% of the total). Moreover, root traits including root length, tissue density and biomass were useful predictors of root lifespan. We conclude that both herbaceous and woody plants have fast-cycling modular units and future studies identifying the fast-cycling module across plant species should allow better understanding of how root construction and turnover are linked to whole-plant strategies.
Polyhydroxyalkanoates in waste activated sludge enhances anaerobic methane production through improving biochemical methane potential instead of hydrolysis rate
Authors: Wang Qilin , Sun Jing , Zhang Chang , Xie Guo-Jun , Zhou Xu , Qian Jin , Yang Guojing , Zeng Guangming , Liu Yiqi , Wang Dongbo
Published: January 2016

Anaerobic sludge digestion is the main technology for sludge reduction and stabilization prior to sludge disposal. Nevertheless, methane production from anaerobic digestion of waste activated sludge (WAS) is often restricted by the poor biochemical methane potential and slow hydrolysis rate of WAS. This work systematically investigated the effect of PHA levels of WAS on anaerobic methane production, using both experimental and mathematical modeling approaches. Biochemical methane potential tests showed that methane production increased with increased PHA levels in WAS. Model-based analysis suggested that the PHA-based method enhanced methane production by improving biochemical methane potential of WAS, with the highest enhancement being around 40% (from 192 to 274 L CH4/kg VS added; VS: volatile solid) when the PHA levels increased from 21 to 143 mg/g VS. In contrast, the hydrolysis rate (approximately 0.10 d−1) was not significantly affected by the PHA levels. Economic analysis suggested that the PHA-based method could save $1.2/PE/y (PE: population equivalent) in a typical wastewater treatment plant (WWTP). The PHA-based method can be easily integrated into the current WWTP to enhance methane production, thereby providing a strong support to the on-going paradigm shift in wastewater management from pollutant removal to resource recovery.
Tomato yellow leaf curl virus infection mitigates the heat stress response of plants grown at high temperatures
Authors: Anfoka Ghandi , Moshe Adi , Fridman Lilia , Amrani Linoy , Rotem Or , Kolot Mikhail , Zeidan Mouhammad , Czosnek Henryk , Gorovits Rena
Published: January 2016

Cultured tomatoes are often exposed to a combination of extreme heat and infection with Tomato yellow leaf curl virus (TYLCV). This stress combination leads to intense disease symptoms and yield losses. The response of TYLCV-susceptible and resistant tomatoes to heat stress together with viral infection was compared. The plant heat-stress response was undermined in TYLCV infected plants. The decline correlated with the down-regulation of heat shock transcription factors (HSFs) HSFA2 and HSFB1 and consequently, of HSF-regulated genes Hsp17, Apx1, Apx2 and Hsp90. We proposed that the weakened heat stress response was due to the decreased capacity of HSFA2 to translocate into the nuclei of infected cells. All the six TYLCV proteins were able to interact with tomato HSFA2 in vitro, moreover, coat protein developed complexes with HSFA2 in nuclei. Capturing of HSFA2 by viral proteins could suppress the transcriptional activation of heat stress response genes. Application of both heat and TYLCV stresses was accompanied by the development of intracellular large protein aggregates containing TYLCV proteins and DNA. The maintenance of cellular chaperones in the aggregated state, even after recovery from heat stress, prevents the circulation of free soluble chaperones, causing an additional decrease in stress response efficiency.
Ocean acidification increases cadmium accumulation in marine bivalves: a potential threat to seafood safety
Authors: Shi Wei , Zhao Xinguo , Han Yu , Che Zhumei , Chai Xueliang , Liu Guangxu
Published: January 2016

To date, the effects of ocean acidification on toxic metals accumulation and the underlying molecular mechanism remains unknown in marine bivalve species. In the present study, the effects of the realistic future ocean pCO2 levels on the cadmium (Cd) accumulation in the gills, mantle and adductor muscles of three bivalve species, Mytilus edulis, Tegillarca granosa and Meretrix meretrix, were investigated. The results obtained suggested that all species tested accumulated significantly higher Cd (p < 0.05) in the CO2 acidified seawater during the 30 days experiment and the health risk of Cd (based on the estimated target hazard quotients, THQ) via consumption of M. meretrix at pH 7.8 and 7.4 significantly increased 1.21 and 1.32 times respectively, suggesting a potential threat to seafood safety. The ocean acidification-induced increase in Cd accumulation may have occurred due to (i) the ocean acidification increased the concentration of Cd and the Cd2+/Ca2+ in the seawater, which in turn increased the Cd influx through Ca channel; (ii) the acidified seawater may have brought about epithelia damage, resulting in easier Cd penetration; and (iii) ocean acidification hampered Cd exclusion.
Comparative analysis of the major constituents in three related polygonaceous medicinal plants using pressurized liquid extraction and HPLC-ESI/MS
Authors: Feng Jiafu , Ren Huazhong , Gou Qiufen , Zhu Lin , Ji Hong , Yi Tao
Published: January 2016

A high-performance liquid chromatography coupled with a diode array detector and electrospray ionization mass spectrometry method was developed for the simultaneous analysis of fourteen characteristic components in roots of three related polygonaceous medicinal plants.
Characteristic redshift and intensity enhancement as far-IR fingerprints of the halogen bond involving aromatic donors
Authors: Vasylyeva Vera , Catalano Luca , Nervi Carlo , Gobetto Roberto , Metrangolo Pierangelo , Resnati Giuseppe
Published: January 2016

Characteristic redshift and intensity enhancement of the C–I stretching band have been proven to be distinct signatures of the halogen bond involving iodopentafluorobenzene.
In situ synthesis of porous ZnO-embedded Zn1−xCdxS/CdS heterostructures for enhanced photocatalytic activity
Authors: Chen Rong , Li Kui , Zhu Xiao-Shu , Xie Shuai-Lei , Dong Long-Zhang , Li Shun-Li , Lan Ya-Qian
Published: January 2016

The in situ embedding of a ZnO cocatalyst on the fine-grained Zn1−xCdxS/CdS heterostructure dramatically improves its photocatalytic activity even in the absence of hole scavengers and makes the utilization of methanol solution as the sacrificial agent for sulfide semiconductors possible.
Cascade polycyclizations in natural product synthesis
Authors: Ardkhean R. , Caputo D. F. J. , Morrow S. M. , Shi H. , Xiong Y. , Anderson E. A.
Published: January 2016

Cascade (domino) reactions have an unparalleled ability to generate molecular complexity from relatively simple starting materials; these transformations are particularly appealing when multiple rings are forged during this process.
Water-soluble perylenediimides: design concepts and biological applications
Authors: Sun Mengmeng , Müllen Klaus , Yin Meizhen
Published: January 2016

Water-soluble perylenediimides (PDIs) with high fluorescence intensity, photostability and biocompatibility have been successfully prepared and applied in the biological field.
Coinage metal coordination chemistry of stable primary, secondary and tertiary ferrocenylethyl-based phosphines
Authors: Azizpoor Fard M. , Rabiee Kenaree A. , Boyle P. D. , Ragogna P. J. , Gilroy J. B. , Corrigan J. F.
Published: January 2016

Ferrocene-based phosphines constitute an important auxiliary ligand in inorganic chemistry.
808 nm photocontrolled UCL imaging guided chemo/photothermal synergistic therapy with single UCNPs-CuS@PAA nanocomposite
Authors: Liu Bei , Li Chunxia , Xie Zhongxi , Hou Zhiyao , Cheng Ziyong , Jin Dayong , Lin Jun
Published: January 2016

Recently, incorporating multiple components into one nanostructured matrix to construct a multifunctional nanomedical platform has attracted more and more attention for simultaneous anticancer diagnosis and therapy.
Impact of metallurgical activities on the content of trace elements in the spatial soil and plant parts of Rubus fruticosus L.
Authors: Nujkić M. M. , Dimitrijević M. M. , Alagić S. Č. , Tošić S. B. , Petrović J. V.
Published: January 2016

Impact of pyrometallurgical copper production on the environment with special emphasis on soil and wild blackberry.
A two-stage microresistive pulse immunosensor for pathogen detection
Authors: Han Yu , Wu Haiyan , Cheng Gang , Zhe Jiang
Published: January 2016

We present a two-stage immunosensor for pathogen detection in a mixed population.
Zinc sensing by metal-responsive transcription factor 1 (MTF1) controls metallothionein and ZnT1 expression to buffer the sensitivity of the transcriptome response to zinc
Authors: Hardyman J. E. J. , Tyson J. , Jackson K. A. , Aldridge C. , Cockell S. J. , Wakeling L. A. , Valentine R. A. , Ford D.
Published: January 2016

Without MTF1, zinc buffering by metallothioneins is reduced; hence, the sensitivity of the non-MTF1-controlled zinc-responsive transcriptome is augmented.
Sequential Michael addition/retro-Claisen condensation of aromatic β-diketones with α,β-unsaturated esters: an approach to obtain 1,5-ketoesters
Authors: Cai Gui-Xin , Wen Jing , Lai Ting-Ting , Xie Dan , Zhou Cheng-He
Published: January 2016

A K2CO3-catalyzed one-pot protocol involving sequential C–C bond formation and cleavage of aromatic β-diketones with α,β-unsaturated esters is developed to obtain 1,5-ketoesters, proceeding smoothly under mild conditions in up to 98% isolated yield.
Binary nickel–iron nitride nanoarrays as bifunctional electrocatalysts for overall water splitting
Authors: Jiang Ming , Li Yingjie , Lu Zhiyi , Sun Xiaoming , Duan Xue
Published: January 2016

Electrochemical water splitting provides a facile method for high-purity hydrogen production, but electro-catalysts with a stable bifunctional activity towards both oxygen and hydrogen evolution have been rarely developed.
Degradation of organic pollutants by NiFe2O4/peroxymonosulfate: efficiency, influential factors and catalytic mechanism
Authors: Wang Zilin , Du Yunchen , Liu Yulei , Zou Bohua , Xiao Jiayue , Ma Jun
Published: January 2016

Catalytic performance of NiFe2O4/PMS system as advanced oxidation technologies in pure water and actual water was studied, and various influential factors and catalytic mechanism were also investigated.
Enhanced in vivo tumour imaging by EDTA-bis-GNGR functionalized core shell CdSe:ZnS quantum dot: synergistic effect of active passive targeting
Authors: Mathur Rashi , Bag Narmada , Varshney Raunak , Hussain Firasat , Kaul Ankur , Kumari Neelam , Chauhan Ramprakash , Singh Shivani , Singh Sweta , Mishra Anil. K.
Published: January 2016

Use of QD-homodimeric system enhances tumour targeting due to the synergistic effect of active passive targeting.
Transparent ZnO-nanowire-based device for UV light detection and ethanol gas sensing on c-Si solar cell
Authors: Lin Chih-hung , Chang Shoou-Jinn , Chen Wei-Shou , Hsueh Ting-Jen
Published: January 2016

In this study, a transparent ZnO nanowire (NW)-based device for ethanol gas sensing and ultraviolet (UV) detection was fabricated and deposited onto an indium tin oxide/crystalline silicon (c-Si) solar cell.
Microwave synthesis of carbon dots with multi-response using denatured proteins as carbon source
Authors: Liu Xue , Li Tianze , Hou Yu , Wu Qiuhua , Yi Jie , Zhang Guolin
Published: January 2016

Carbon dots were prepared through a one-step microwave treatment of denatured proteins, which show responsiveness for pH, temperature and metal ions. Metal ions specific detection can be realized through screening appropriate protein carbon source.
Slipperiness and stability of hydrophilic surfaces coated with a lubricating fluid
Authors: Pant Reeta , Roy Pritam Kumar , Nagarajan Arun Kumar , Khare Krishnacharya
Published: January 2016

Stable slippery lubricating-fluid-coated surfaces on smooth hydrophilic silicon surfaces.
The removal of heavy metal ions from wastewater/aqueous solution using polypyrrole-based adsorbents: a review
Authors: Muhammad Ekramul Mahmud Habibun Nabi , Huq A. K. Obidul , Yahya Rosiyah binti
Published: January 2016

Water pollution caused by heavy metal ions is becoming a serious threat to human and aquatic lives day by day.
Defluoridation by rice spike-like akaganeite anchored graphene oxide
Authors: Iiu Yuyang , Lv Jiaxin , Jin Wei , Zhao Yaping
Published: January 2016

The fluoride remediation rate was greatly enhanced by β-FeOOH dispersing on Grephene oxide.
Microwave-assisted synthesis of 3-sulfenylindoles by sulfonyl hydrazides using organic ionic base-Brønsted acid
Authors: Rahaman Rajjakfur , Devi Namita , Sarma Kuladip , Barman Pranjit
Published: January 2016

3-Sulfenylation of indoles by sulfonyl hydrazides using organic ionic base-Bronsted acid sulfonyl hydrazides as thiol surrogate.
Mixing control by frequency variable magnetic micropillar
Authors: Yu Hao , Nguyen Thien-Binh , Ng Sum Huan , Tran Tuan
Published: January 2016

We demonstrate an active mixing enhancement method based on actuation of a single magnetic micropillar with variable beating frequency.
Rapid synthesis of alkylaminophenols via the Petasis borono–Mannich reaction using protonated trititanate nanotubes as robust solid–acid catalysts
Authors: Prasad Reddy Bhoomireddy Rajendra , Govardhana Reddy Peddiahgari Vasu , Kumar Dharani Praveen , Reddy Bijivemula N. , Shankar Muthukonda V.
Published: January 2016

The Petasis borono–Mannich reaction was applied to the synthesis of alkylaminophenols from o-hydroxybenzaldehydes, secondary amines and boronic acids in the presence of H2Ti3O7 nanotubes as reusable solid–acid catalysts.
Thermodynamic properties of pure and doped (B, N) graphene
Authors: Mann Sarita , Rani Pooja , Kumar Ranjan , Dubey Girija S. , Jindal V. K.
Published: January 2016

Ab initio density functional perturbation theory (DFPT) has been employed to study the thermodynamical properties of pure and doped graphene sheet and the results have been compared with available theoretical and experimental data.
Mesoporous silica nanosphere supported platinum nanoparticles (Pt@MSN): one-pot synthesis and catalytic hydrogen generation
Authors: Irum Maria , Zaheer Muhammad , Friedrich Martin , Kempe Rhett
Published: January 2016

One-pot synthesis of mesoporous silica nanosphere (MSN) supported platinum nanoparticles (NPs) as catalysts for hydrogen generation from alkaline sodium borohydride is reported.
Integrated microfluidic device for the spherical hydrogel pH sensor fabrication
Authors: Sun Yawei , Zhang Yaopeng , Liu Jingjing , Nie Fuqiang
Published: January 2016

A type of inverse opal hydrogel pH sensor with homogeneous structural colour were generated from an integrated microfluidic chip.
High-throughput metabolic profiling for discovering metabolic biomarkers of sepsis-induced acute lung injury
Authors: Liang Qun , Liu Han , Jiang Yan , Xing Haitao , Zhang Tianyu , Ai-hua Zhang
Published: January 2016

Sepsis-induced acute lung injury (ALI) remains a leading cause of death in intensive care units and early detection is very important. This work showed that metabolite phenotype profiling might be a useful tool for the effective diagnosis and further understanding of ALI.
Disinfection of water by pulsed power technique: a mechanistic perspective
Authors: Singh Raj Kamal , Philip Ligy , Ramanujam Sarathi
Published: January 2016

A detailed sub-cellular level bacterial disinfection mechanism and perturbation of bacterial surface potential due to ROS/RNS in pulsed plasma treatment.
Bilayer quantum dot-decorated mesoscopic inverse opals for high volumetric photoelectrochemical water splitting efficiency
Authors: Lee Jaemin , Cho Chang-Yeol , Lee Doh C. , Moon Jun Hyuk
Published: January 2016

We introduce a mesoscopic inverse opal structure sensitized by CdSe/CdS nanoparticle bilayer for use as water splitting electrodes.
3D flexible hydrogen evolution electrodes with Se-promoted molybdenum sulfide nanosheet arrays
Authors: Pu Zonghua , Wei Shiyong , Chen Zhibao , Mu Shichun
Published: January 2016

Se-promoted molybdenum sulfide nanosheet arrays supported on carbon cloth are developed as a novel electrocatalyst for hydrogen evolution reaction.
High proton conductivity at low relative humidity in an anionic Fe-based metal–organic framework
Authors: Tu Thach N. , Phan Nghi Q. , Vu Thanh T. , Nguyen Ha L. , Cordova Kyle E. , Furukawa Hiroyasu
Published: January 2016

High proton conductivity (2.90 × 10−2 S cm−1) in an anionic Fe-based metal–organic framework was reached under more practical operating conditions (95 °C and 60% RH).
Electrochemical synthesis of Au–MnO2 on electrophoretically prepared graphene nanocomposite for high performance supercapacitor and biosensor applications
Authors: Veeramani Vediyappan , Dinesh Bose , Chen Shen-Ming , Saraswathi Ramiah
Published: January 2016

An electrochemical synthesis of an Au–MnO2–graphene nanocomposite electrode for supercapacitor and biosensor applications.
STAT3 methylation in white blood cells as a novel sensitive biomarker for the toxic effect of low-dose benzene exposure
Authors: Liu Di , Chen Yujiao , Sun Pengling , Bai Wenlin , Gao Ai
Published: January 2016

A cross-sectional study was conducted in a sample of 571 workers to explore the toxic effect and early sensitive biomarker of the health effects of low-dose benzene exposure (LDBE), as well as the correlation between DNA methylation and the toxic effect of LDBE.
Investigation of room temperature deposited silicon dioxide thin films for surface texturisation of monocrystalline {100} silicon
Authors: Ashok Akarapu , Pal Prem
Published: January 2016

In the fabrication of crystalline silicon‐based solar cells, silicon surface is usually texturised by wet anisotropic etchant without using any masking pattern. This method provides randomly oriented upright pyramids (or hillocks) of varying sizes. However, a surface textured with inverted pyramids yields high efficiency compared with the one textured with normal pyramids. Silicon dioxide thin films synthesised using anodic oxidation technique at room temperature are explored as etch mask in KOH solutions to texturise the Si{100} surface with inverted pyramids without patterning of the oxide layer using lithography. Oxide films of ∼50 nm thickness are synthesised in different compositions of the electrolyte under potentiodynamic regime. Thickness uniformity and refractive index of the as‐grown oxide films are measured using spectroscopic ellipsometry. Scanning electron microscope is primarily used to inspect the etched surface morphology. The composition of the electrolyte, KOH concentration and etching time are optimised for the maximum surface coverage of inverted pyramids. The surface texturing process demonstrated is very simple and economic as it utilises anodic silicon dioxide as an etch mask, which is deposited by a simple experimental setup and the process does not involve any lithography step.
Microwave‐assisted fabrication of superhydrophobic surfaces on aluminium foil and the anti‐corrosion properties
Authors: Lu Yang , Huang Lina , Cao Xin Xin , Wang Libo
Published: January 2016

Superhydrophobic surface on aluminium (Al) substrate was successfully fabricated via a microwave‐assisted process by immersing the clean pure Al substrate into the mixed solution of Zn(NO3)2 and hexamethylenetetramine, and modified with stearic acid (STA). Surface morphology and composition were characterised by using scanning electron microscopy (SEM), X‐ray diffraction and X‐ray photoelectron spectroscopy. The wettability and the corrosion resistance properties of the surface modified with STA were characterised. The results show that the sample had a high water contact angle of about 155°. It has good anti‐corrosion for alkali and 3.5 wt% sodium chloride solution. From SEM images, it was found that abundant regular micronano sheets distributed on the surface at random and there are large amount of interspace amount the sheets. The special structure and the low surface energy make the Al foil have superhydrophobic surfaces.
Pre-switching bifurcation of a slender jet
Authors: Audier P. , Sciamarella D. , Artana G.
Published: January 2016

In this work, we study the near-field of the jet flow exiting a slot-model with aspect ratio 7.5:1. The core of the slender jet separates into two streams which subsequently merge recomposing a single core jet. Axis switching occurs downstream following self-similarity rules. In order to unveil the 3D dynamics of this pre-switching bifurcation, stereo-PIV (Particle Image Velocimetry) measurements are performed and a phase-locking technique is implemented using surface dielectric barrier discharge plasma actuators. The device forces the flow with low-amplitude localized disturbances to produce a lock-on phenomenon. The symmetric modes of the Crow instability, developing between the counter-rotating vortex tubes formed at the slot exit, are found to account for the bifurcation process.
Hydrogen-carbon complexes and the blue luminescence band in GaN
Authors: Demchenko D. O. , Diallo I. C. , Reshchikov M. A.
Published: January 2016

The blue luminescence band with a maximum at 3.0 eV and the zero-phonon line at 3.33 eV (labeled BL2) is observed in high-resistivity GaN. Under prolonged ultraviolet (UV) light exposure, the BL2 band transforms into the yellow luminescence (YL) band with a maximum at 2.2 eV. Our hybrid functional calculations suggest that the BL2 band is related to a hydrogen-carbon defect complex, either CNON-Hi or CN-Hi. The complex creates defect transition level close to the valence band, which is responsible for the BL2 band. Under UV illumination, the complex dissociates, leaving as byproduct the source of the YL band (CNON or CN) and interstitial hydrogen.
A whole-path importance-sampling scheme for Feynman path integral calculations of absolute partition functions and free energies
Authors: Mielke Steven L. , Truhlar Donald G.
Published: January 2016

Using Feynman path integrals, a molecular partition function can be written as a double integral with the inner integral involving all closed paths centered at a given molecular configuration, and the outer integral involving all possible molecular configurations. In previous work employing Monte Carlo methods to evaluate such partition functions, we presented schemes for importance sampling and stratification in the molecular configurations that constitute the path centroids, but we relied on free-particle paths for sampling the path integrals. At low temperatures, the path sampling is expensive because the paths can travel far from the centroid configuration. We now present a scheme for importance sampling of whole Feynman paths based on harmonic information from an instantaneous normal mode calculation at the centroid configuration, which we refer to as harmonically guided whole-path importance sampling (WPIS). We obtain paths conforming to our chosen importance function by rejection sampling from a distribution of free-particle paths. Sample calculations on CH4 demonstrate that at a temperature of 200 K, about 99.9% of the free-particle paths can be rejected without integration, and at 300 K, about 98% can be rejected. We also show that it is typically possible to reduce the overhead associated with the WPIS scheme by sampling the paths using a significantly lower-order path discretization than that which is needed to converge the partition function.
Effect of structural disorder on quantum oscillations in graphite
Authors: Camargo B. C. , Kopelevich Y. , Usher A. , Hubbard S. B.
Published: January 2016

We have studied the effect of structural disorder on the de Haas van Alphen and Shubnikov de Haas quantum oscillations measured in natural, Kish, and highly oriented pyrolytic graphite samples at temperatures down to 30 mK and at magnetic fields up to 14 T. The measurements were performed on different samples characterized by means of x-ray diffractometry, transmission electron microscopy, and atomic-force microscopy techniques. Our results reveal a correlation between the amplitude of quantum oscillations and the sample surface roughness.
Comparison of fluid neutral models for one-dimensional plasma edge modeling with a finite volume solution of the Boltzmann equation
Authors: Horsten N. , Dekeyser W. , Samaey G. , Baelmans M.
Published: January 2016

We derive fluid neutral approximations for a simplified 1D edge plasma model, suitable to study the neutral behavior close to the target of a nuclear fusion divertor, and compare its solutions to the solution of the corresponding kinetic Boltzmann equation. The plasma is considered as a fixed background extracted from a detached 2D simulation. We show that the Maxwellian equilibrium distribution is already obtained very close to the target, justifying the use of a fluid approximation. We compare three fluid neutral models: (i) a diffusion model; (ii) a pressure-diffusion model (i.e., a combination of a continuity and momentum equation) assuming equal neutral and ion temperatures; and (iii) the pressure-diffusion model coupled to a neutral energy equation taking into account temperature differences between neutrals and ions. Partial reflection of neutrals reaching the boundaries is included in both the kinetic and fluid models. We propose two methods to obtain an incident neutral flux boundary condition for the fluid models: one based on a diffusion approximation and the other assuming a truncated Chapman-Enskog distribution. The pressure-diffusion model predicts the plasma sources very well. The diffusion boundary condition gives slightly better results overall. Although including an energy equation still improves the results, the assumption of equal ion and neutral temperature already gives a very good approximation.
Plasma flow in peripheral region of detached plasma in linear plasma device
Authors: Hayashi Y. , Ohno N. , Kajita S. , Tanaka H.
Published: January 2016

A plasma flow structure is investigated using a Mach probe under detached plasma condition in a linear plasma device NAGDIS-II. A reverse flow along the magnetic field is observed in a steady-state at far-peripheral region of the plasma column in the upstream side from the recombination front. These experimental results indicate that plasma near the recombination front should strongly diffuse across the magnetic field, and it should be transported along the magnetic field in the reverse flow direction. Furthermore, bursty plasma density fluctuations associated with intermittent convective plasma transport are observed in the far-peripheral region of the plasma column in both upstream and downstream sides from the recombination front. Such a nondiffusive transport can contribute to the intermittent reverse plasma flow, and the experimental results indicate that intermittent transports are frequently produced near the recombination front.
The transfer of atmospheric-pressure ionization waves via a metal wire
Authors: Xia Yang , Liu Dongping , Wang Wenchun , Peng Yifeng , Niu Jinhai , Bi Zhenhua , Ji Longfei , Song Ying , Wang Xueyang , Qi Zhihua
Published: January 2016

Our study has shown that the atmospheric-pressure He ionization waves (IWs) may be transferred from one dielectric tube (tube 1) to the other one (tube 2) via a floating metal wire. The propagation of IWs along the two tubes is not affected by the diameter of a floating metal wire, however, their propagation is strongly dependent on the length of a floating metal wire. The propagation of one IW along the tube 1 may result in the second IW propagating reversely inside the tube in vicinity of a floating metal wire, which keeps from their further propagation through the tube 1. After they merge together as one conduction channel inside the tube 1, the transferred plasma bullet starts to propagate along the tube 2. The propagation of transferred plasma bullets along the tube 2 is mainly determined by the capacitance and inductance effects, and their velocity and density can be controlled by the length of a floating metal wire.
A first-order antiferromagnetic-paramagnetic transition induced by structural transition in GeNCr3
Authors: Zu L. , Lin S. , Liu Y. , Lin J. C. , Yuan B. , Kan X. C. , Tong P. , Song W. H. , Sun Y. P.
Published: January 2016

A first-order antiferromagnetic (AFM)-paramagnetic (PM) phase transition has been confirmed by systematic magnetic measurements in GeNCr3, and it does not depend on the applied magnetic fields. Interestingly, a structural transition from space group P-421m to I4/mcm without breaking tetragonal symmetry appears around this AFM-PM transition temperature, which may be the driving force for the AFM-PM transition. Moreover, obvious exothermic and endothermic peaks in calorimetric measurements, a sharp peak of specific heat Cp(T), and a slope change of resistivity ρ(T) are also observed around structural transition temperature, indicating a strong coupling between structure and electrical as well as thermal properties.
Nonpolar III-nitride vertical-cavity surface-emitting laser with a photoelectrochemically etched air-gap aperture
Authors: Leonard J. T. , Yonkee B. P. , Cohen D. A. , Megalini L. , Lee S. , Speck J. S. , DenBaars S. P. , Nakamura S.
Published: January 2016

We demonstrate a III-nitride nonpolar vertical-cavity surface-emitting laser (VCSEL) with a photoelectrochemically (PEC) etched aperture. The PEC lateral undercut etch is used to selectively remove the multi-quantum well (MQW) region outside the aperture area, defined by an opaque metal mask. This PEC aperture (PECA) creates an air-gap in the passive area of the device, allowing one to achieve efficient electrical confinement within the aperture, while simultaneously achieving a large index contrast between core of the device (the MQW within the aperture) and the lateral cladding of the device (the air-gap formed by the PEC etch), leading to strong lateral confinement. Scanning electron microscopy and focused ion-beam analysis is used to investigate the precision of the PEC etch technique in defining the aperture. The fabricated single mode PECA VCSEL shows a threshold current density of ∼22 kA/cm2 (25 mA), with a peak output power of ∼180 μW, at an emission wavelength of 417 nm. The near-field emission profile shows a clearly defined single linearly polarized (LP) mode profile (LP12,1), which is in contrast to the filamentary lasing that is often observed in III-nitride VCSELs. 2D mode profile simulations, carried out using COMSOL, give insight into the different mode profiles that one would expect to be displayed in such a device. The experimentally observed single mode operation is proposed to be predominantly a result of poor current spreading in the device. This non-uniform current spreading results in a higher injected current at the periphery of the aperture, which favors LP modes with high intensities near the edge of the aperture.
Structure, strain, and composition profiling of InAs/GaAs(211)B quantum dot superlattices
Authors: Florini N. , Dimitrakopulos G. P. , Kioseoglou J. , Germanis S. , Katsidis C. , Hatzopoulos Z. , Pelekanos N. T. , Kehagias Th.
Published: January 2016

The morphology, nanostructure, and strain properties of InAs quantum dots (QDs) grown on GaAs(211)B, uncapped or buried, are explored by transmission electron microscopy and related quantitative techniques. Besides the built-in piezoelectric field, other differences of (211) growth compared to (100)-oriented growth are discussed in terms of the (211) surface non-singularity, leading to anisotropic shape of the QDs and local chemical inhomogeneity of the wetting layer. The shape of the uncapped QDs was precisely defined as truncated pyramidal, elongated along the 〈111〉 direction, and bounded by the {110}, {100}, and {213} facets. Local strain measurements showed that large surface QDs were almost unstrained due to plastic relaxation, exhibiting small residual elastic strain at the interface that gradually diminished toward their apex. Conversely, buried QDs were pseudomorphically grown on GaAs. By postulating a plane stress state, we have established a systematic increase of the local strain from the base toward the apex region of the QDs. Using Vegard's law, their chemical composition profiles were calculated, revealing an indium content gradient along the growth direction and compositional variants among different QDs. Photoluminescence measurements showed variations in emission energy between the QDs and consistency with a graded In-content, which complied with the quantitative strain analysis.
The Portuguese Diaspora in Europe
Authors: Newitt Malyn
Published: January 2016

Educated Portuguese have often looked abroad for career opportunities and this chapter looks at some categories of these estrangeirados, ranging from princesses to diplomats, political exiles, writers and artists. Parts of Portugal have always been closely integrated into the economy of Spain where seasonal migrants sought work. With the formation of the European Common Market large numbers of Portuguese settled in France and Germany and in more recent times in Switzerland, Luxemburg and Britain. This chapter looks at the experience of emigrants in these countries and reflects on their continuing impact on communities in Portugal. It became more common for emigrants to return either seasonally or on retirement and for them to retain links with the communities from which they departed.
Interference
Authors: Guenther B. D.
Published: January 2016

The sum of solutions of the wave equation is also a solution. This property of the wave equation is called the superposition principle. The physical consequence of this principle is the observation of bright and dark bands of light called fringes when a number of waves coexist in a region in space. The bright regions occur when a number of waves add together to produce an intensity maximum of the resultant wave; this is called constructive interference. Destructive interference occurs when a number of waves add together to produce an intensity minimum of the resultant wave. Techniques for adding waves are used in this chapter to develop a theoretical explanation of the interference patterns produced by a number of simple physical systems, such as two slits, a thin dielectric layer, and a Fabry–Perot cavity. The design of dielectric layers for mirrors and antireflection coatings is also discussed.
Geometrical Optics
Authors: Guenther B. D.
Published: January 2016

The theory of geometrical optics as presented here is associated with rays that propagate at small angles where the sine of the angle can be replaced by the angle in radians. This is called the paraxial theory and it fails to describe the actual performance of an optical system. The departures of the paraxial predictions from actual performance are called aberrations, and the various types are introduced: spherical aberration, coma, astigmatism, field curvature, and distortion. Geometrical optics and the concept of total reflection are used to derive a simple theory of guided waves. Some of the basic properties of guided waves are obtained using this simple theory. The Lagrangian formulation of geometrical optics is used to prove that rectilinear propagation is obtained when the propagation medium is homogeneous and to derive the propagation in an optical fiber with an index of refraction that varies in the radial direction.
Mythological Allusion in the Odyssey: Herakles and the Bow of Odysseus
Authors: Schein Seth L.
Published: January 2016

Mythological allusion helps to define the subject matter of the Odyssey and its poetic genre, in contrast to that of the Iliad and its genre. In the Iliad, mythological allusion typically works to exclude other than the poem’s distinctive themes and values; in the Odyssey, they contribute to the poem’s inclusion of other than its own distinctive ways of narrating and evaluating its characters’ actions and sufferings. The story of the bow at Od. 21.11–41 is a good example of the Odyssean mode of allusion. The bow is a symbol of Odysseus’ ethical complexity and distinctive heroic identity: it associates him with the positive and negative features of Herakles as hero model and betrayer of his guest friend, and also is the instrument and symbol of Odysseus’ rightful domestic and political authority, as affirmed by his victory in the bride contest for Penelope and morally questionable slaughter of the Suitors.
Divine and Human in the Homeric Hymn to Aphrodite
Authors: Schein Seth L.
Published: January 2016

The Homeric Hymn to Aphrodite (HHAphr) artfully combines a series of contrasts between humanity and divinity with cosmic history in a special kind of religious poetry that is unique in archaic Greek epic as we know it. The Iliad, Odyssey, and Works and Days are concerned mainly with the human condition, the Theogony and most of the Homeric Hymns with the gods and the genesis of the cosmic order. Only HHAphr and the Homeric Hymn to Demeter (HHDem) make divinity and humanity coequal poetic themes, and only HHAphr ends with the goddess’s defeat and a radical diminution of her power, even as her gifts enable Anchises to transcend the limits of mortality through sexual pleasure, fertility, and a royal lineage. Close attention to diction, style, and narrative technique clarifies how artfully the poem celebrates ‘the works of Aphrodite’ by narrating her simultaneous defeat and triumph and those of Anchises.
Homeric Intertextuality: Two Examples
Authors: Schein Seth L.
Published: January 2016

This chapter illustrates how the Odyssey gains poetic force form its intertextuality with the Iliad, or with the poetic tradition behind the Iliad. In my first example, each poem uses the same formulaic verse, evoking the same traditional theme. The Iliad does so en passant, while the Odyssey self-consciously integrates the verse and its thematic resonance into the account of the fight between Odysseus and the beggar Iros in Book 18. In my second example, the Odyssey clearly alludes in Book 22 to a heroic attitude and way of speaking that are characteristically Iliadic and, in particular, Achillean. It thus represents Odysseus’ heroism at this point in the poem as uncharacteristically and significantly Achillean. It is unclear whether the Odyssey refers intertextually to the Iliad as we know it or to a traditional kind of heroic mood and values on which the Iliad too drew to characterize its main hero.
Measuring the dynamics of global business cycle connectedness
Authors: Diebold Francis X. , Yilmaz Kamil
Published: January 2016

Using a connectedness measurement technology fundamentally grounded in modern network theory, the chapter measures real output connectedness for a set of six developed countries, from 1962 to 2010. It shows that global connectedness is sizable and time-varying over the business cycle, and it studies the nature of the time variation relative to the ongoing discussion about the changing nature of the global business cycle. It also shows that connectedness corresponding to transmissions to others from the United States and Japan is disproportionately important. The data used in this analysis is quite different to earlier works; industrial production indexes at monthly intervals allows the connectedness of business cycle shocks to be captured much faster.
Estimation of radiation risk in presence of classical additive and Berkson multiplicative errors in exposure doses
Authors: Masiuk S. V. , Shklyar S. V. , Kukush A. G. , Carroll R. J. , Kovgan L. N. , Likhtarov I. A.
Published: January 2016

In this paper, the influence of measurement errors in exposure doses in a regression model with binary response is studied. Recently, it has been recognized that uncertainty in exposure dose is characterized by errors of two types: classical additive errors and Berkson multiplicative errors. The combination of classical additive and Berkson multiplicative errors has not been considered in the literature previously. In a simulation study based on data from radio-epidemiological research of thyroid cancer in Ukraine caused by the Chornobyl accident, it is shown that ignoring measurement errors in doses leads to overestimation of background prevalence and underestimation of excess relative risk. In the work, several methods to reduce these biases are proposed. They are new regression calibration, an additive version of efficient SIMEX, and novel corrected score methods.
Error Correction Methods with Political Time Series
Authors: Grant Taylor , Lebo Matthew J.
Published: January 2016

While traditionally considered for non-stationary and cointegrated data, DeBoef and Keele suggest applying a General Error Correction Model (GECM) to stationary data with or without cointegration. The GECM has since become extremely popular in political science but practitioners have confused essential points. For one, the model is treated as perfectly flexible when, in fact, the opposite is true. Time series of various orders of integration–stationary, non-stationary, explosive, near- and fractionally integrated–should not be analyzed together but researchers consistently make this mistake. That is, withoutequation balancethe model is misspecified and hypothesis tests and long-run-multipliers are unreliable. Another problem is that the error correction term's sampling distribution moves dramatically depending upon the order of integration, sample size, number of covariates, and theboundednessofYt.This means that practitioners are likely to overstate evidence of error correction, especially when using a traditionalt-test. We evaluate common GECM practices with six types of data, 746 simulations, and five paper replications.
Introduction to Symposium on Time Series Error Correction Methods in Political Science
Authors: Box-Steffensmeier Janet , Helgason Agnar Freyr
Published: January 2016

In recent years, political science has seen a boom in the use of sophisticated methodological tools for time series analysis. One such tool is the general error correction model (GECM), originally introduced to political scientists in the pages of this journal over 20 years ago (Durr 1992; Ostrom and Smith 1992) and re-introduced by De Boef and Keele (2008), who advocate its use for a wider set of time series data than previously considered appropriate. Their article has proven quite influential, with numerous papers justifying their methodological choices with reference to De Boef and Keele's contribution.

Grant and Lebo (2016) take issue with the increasing use of the GECM in political science and argue that the methodology is widely misused and abused by practitioners. Given the recent surge of research conducted using error correction methods, there is every reason to take their suggestions seriously and provide a fuller discussion of the points they raise in their paper. The present symposium serves such a role. It consists of Grant and Lebo's critique, a detailed response by Keele, Linn, and Webb (2016b), and shorter comments by Esarey (2016), Freeman (2016), and Helgason (2016). Finally, Lebo and Grant (2016) and Keele, Linn, and Webb (2016a) reflect on the contributions made in the symposium, as well as discuss outstanding issues.
Structural and functional analysis of the RNA helicase Prp43 from the thermophilic eukaryoteChaetomium thermophilum
Authors: Tauchert Marcel J. , Fourmann Jean-Baptiste , Christian Henning , Lührmann Reinhard , Ficner Ralf
Published: January 2016

RNA helicases are indispensable for all organisms in each domain of life and have implications in numerous cellular processes. The DEAH-box RNA helicase Prp43 is involved in pre-mRNA splicing as well as rRNA maturation. Here, the crystal structure ofChaetomium thermophilumPrp43 at 2.9 Å resolution is revealed. Furthermore, it is demonstrated that Prp43 fromC. thermophilumis capable of functionally replacing its orthologue fromSaccharomyces cerevisiaein spliceosomal disassembly assays.
Cloning, expression, purification, crystallization and initial crystallographic analysis of FleN fromPseudomonas aeruginosa
Authors: Harshita  , Chanchal  , Jain Deepti
Published: January 2016

The assembly of bacterial flagella requires the coordinated expression of a large number of genes in a hierarchical manner. These genes code for structural components of flagella, regulatory components and components that are required for chemotaxis. Stringent spatial and numerical control of flagella biosynthesis is essential for promoting motility and pathogenesis in bacteria. These genes are regulated at the level of transcription. FleN, a P-loop-containing ATPase, plays an important role in maintaining flagellar number inPseudomonas aeruginosa. FleN exhibits anti-activator activity against FleQ, the global transcriptional regulator of flagellar genes. In order to gain insights into the regulatory mechanism of flagella synthesis, full-length FleN was crystallized in complex with the nonhydrolyzable ATP analogue β,γ-imidoadenosine 5′-triphosphate (AMPPNP) in space groupC2221, with unit-cell parametersa= 49.1,b= 206.9,c= 103.3 Å. The Matthews coefficient is 2.19 Å3 Da−1assuming the presence of two molecules in the asymmetric unit, and the corresponding solvent content is 43.7%. X-ray diffraction data were collected to a minimum Bragg spacing of 2.21 Å and crystals of FleN–AMPPNP were prepared with selenomethionine-labelled FleN forab initiophasing.
Crystal structure of (μ-1,4-dicarboxybutane-1,4-dicarboxylato)bis[bis(triphenylphosphane)silver(I)] dichloromethane trisolvate
Authors: Frenzel Peter , Korb Marcus , Lang Heinrich
Published: January 2016

The molecular structure of the tetrakis(triphenylphosphanyl)disilver salt of butane-1,1,4,4-tetracarboxylic acid, [Ag2(C8H8O8)(C18H15P)4]·3CH2Cl2, crystallizes with one and a half molecules of dichloromethane in the asymmetric unit. The coordination complex exhibits an inversion centre through the central CH2—CH2bond. The AgIatom has a distorted trigonal–planar P2O coordination environment. The packing is characterized by intermolecularT-shaped π–π interactions between the phenyl rings of the PPh3substituents in neighbouring molecules, forming a ladder-type superstructure parallel to [010]. These ladders are arranged in layers parallel to (101). Intramolecular hydrogen bonds between the OH group and one O atom of the Ag-bonded carboxylate group results in an asymmetric bidendate coordination of the carboxylate moiety to the AgIion.
Structural characterization of the N-terminal part of the MERS-CoV nucleocapsid by X-ray diffraction and small-angle X-ray scattering
Authors: Papageorgiou Nicolas , Lichière Julie , Baklouti Amal , Ferron François , Sévajol Marion , Canard Bruno , Coutard Bruno
Published: January 2016

The N protein of coronaviruses is a multifunctional protein that is organized into several domains. The N-terminal part is composed of an intrinsically disordered region (IDR) followed by a structured domain called the N-terminal domain (NTD). In this study, the structure determination of the N-terminal region of the MERS-CoV N proteinviaX-ray diffraction measurements is reported at a resolution of 2.4 Å. Since the first 30 amino acids were not resolved by X-ray diffraction, the structural study was completed by a SAXS experiment to propose a structural model including the IDR. This model presents the N-terminal region of the MERS-CoV as a monomer that displays structural features in common with other coronavirus NTDs.