bluuebunny/crossref_metadata_2025 huggingface dataset:
The climate history of early Mars: insights from the Antarctic McMurdo Dry Valleys hydrologic system
Authors: Head James W. , Marchant David R.
Published: November 2014

The early climate of Mars (Noachian Period, the first ~20% of its history) is thought to differ significantly from that of its more recent history (Amazonian Period, the last ~66%) which is characterized by hyperarid, hypothermal conditions that result in mean annual air temperatures (MAAT) well below 0°C, a global cryosphere, minimal melting on the ground surface, and a horizontally stratified hydrologic system. We explore the nature of the fluvial and lacustrine environments in the Mars-like hyperarid, hypothermal McMurdo Dry Valleys (MDV), where the MAAT is well below 0°C (~ -14 to -30°C) in order to assess whether the Late Noachian geologic record can be explained by a climate characterized by “cold and icy” conditions. We find that the MDV hydrological system and cycle provide important insights into the potential configuration of a “cold and icy” early Mars climate in which MDV-like ephemeral streams and rivers, and both closed-basin and open-basin lakes could form. We review a series of MDV fluvial and lacustrine features to guide investigators in the analysis of the geomorphology of early Mars and we outline a new model for the nature and evolution of a “cold and icy” Late Noachian climate based on these observations. We conclude that a cold and icy Late Noachian Mars with MAAT below freezing, but peak seasonal and peak daily temperatures above 0°C, could plausibly account for the array of Noachian-aged fluvial and lacustrine features observed on Mars. Our assessment also provides insight into the potential effects of punctuated warming on a cold and icy early Mars, in which impact crater formation or massive volcanic eruptions cause temperatures in the melting range for decadal to centennial timescales. We outline a set of outstanding questions and tests concerning the nature and evolution of these features on Mars.
Full abstraction for expressiveness: history, myths and facts
Authors: GORLA DANIELE , NESTMANN UWE
Published: November 2014

What does it mean that an encoding is fully abstract? What does itnotmean? In this position paper, we want to help the reader to evaluate the real benefits of using such a notion when studying the expressiveness of programming languages. Several examples and counterexamples are given. In some cases, we work at a very abstract level; in other cases, we give concrete samples taken from the field of process calculi, where the theory of expressiveness has been mostly developed in the last years.
Barriers to access for severe acute malnutrition treatment services in Pakistan and Ethiopia: a comparative qualitative analysis
Authors: Puett Chloe , Guerrero Saul
Published: November 2014

Objective

To understand and compare the primary barriers households face when accessing treatment for cases of childhood severe acute malnutrition (SAM) in different cultural settings with different types of implementing agencies.

Design

The study presents a comparative qualitative analysis of two SAM treatment services, selected to include: (i) one programme implemented by a non-governmental organization and one by a Ministry of Health; and (ii) programmes considered to be successful, defined as either coverage level achieved or extent of integration within government infrastructure. Results from individual interviews and group discussions were recorded and analysed for themes in barriers to access.

Setting

Sindh Province, Pakistan; Tigray Region, Ethiopia.

Subjects

Beneficiary communities and staff of SAM treatment services in two countries.

Results

Common barriers were related to distance, high opportunity costs, knowledge of services, knowledge of malnutrition and child’s refusal of ready-to-use foods. While community sensitization mechanisms were generally strong in these well-performing programmes, in remote areas with less programme exposure, beneficiaries experienced barriers to remaining in the programme until their children recovered.

Conclusions

Households experienced a number of barriers when accessing SAM treatment services. Integration of SAM treatment with other community-based interventions, as the UN recommends, can improve access to life-saving services. Efforts to integrate SAM treatment into national health systems should not neglect the community component of health systems and dedicated funding for the community component is needed to ensure access. Further research and policy efforts should investigate feasible mechanisms to effectively reduce barriers to access and ensure equitable service delivery.
X-Ray Microscopy as an Approach to Increasing Accuracy and Efficiency of Serial Block-Face Imaging for Correlated Light and Electron Microscopy of Biological Specimens
Authors: Bushong Eric A. , Johnson Donald D. , Kim Keun-Young , Terada Masako , Hatori Megumi , Peltier Steven T. , Panda Satchidananda , Merkle Arno , Ellisman Mark H.
Published: November 2014

The recently developed three-dimensional electron microscopic (EM) method of serial block-face scanning electron microscopy (SBEM) has rapidly established itself as a powerful imaging approach. Volume EM imaging with this scanning electron microscopy (SEM) method requires intense staining of biological specimens with heavy metals to allow sufficient back-scatter electron signal and also to render specimens sufficiently conductive to control charging artifacts. These more extreme heavy metal staining protocols render specimens light opaque and make it much more difficult to track and identify regions of interest (ROIs) for the SBEM imaging process than for a typical thin section transmission electron microscopy correlative light and electron microscopy study. We present a strategy employing X-ray microscopy (XRM) both for tracking ROIs and for increasing the efficiency of the workflow used for typical projects undertaken with SBEM. XRM was found to reveal an impressive level of detail in tissue heavily stained for SBEM imaging, allowing for the identification of tissue landmarks that can be subsequently used to guide data collection in the SEM. Furthermore, specific labeling of individual cells using diaminobenzidine is detectable in XRM volumes. We demonstrate that tungsten carbide particles or upconverting nanophosphor particles can be used as fiducial markers to further increase the precision and efficiency of SBEM imaging.
Analysis of elliptical-disk microstrip patch printed on isotropic or anisotropic substrate materials
Authors: Bedra Randa , Bedra Sami , Fortaki Tarek
Published: November 2014

This paper presents a simple approach for accurate determination of the resonant frequency of an elliptical microstrip patch printed on isotropic or anisotropic substrate materials. In this approach, some modifications are made to account for fringe fields, dispersion effects, and losses by calculating effective dimensions, effective permittivity of anisotropy in the layer, and effective loss tangent, respectively. The theoretical resonant frequency results are in very good agreement with the experimental results reported elsewhere. Numerical results show that the change in the resonant frequency of the antenna is due primarily to a small disturbance of the substrate's nature. Then the effect of the uniaxial anisotropic materials is a significant parameter and most essential on the microstrip antenna characterization.
Mitochondrial dysfunction-associated OPA1 cleavage contributes to muscle degeneration: preventative effect of hydroxytyrosol acetate
Authors: Wang X , Li H , Zheng A , Yang L , Liu J , Chen C , Tang Y , Zou X , Li Y , Long J , Liu J , Zhang Y , Feng Z
Published: November 2014

Mitochondrial dysfunction contributes to the development of muscle disorders, including muscle wasting, muscle atrophy and degeneration. Despite the knowledge that oxidative stress closely interacts with mitochondrial dysfunction, the detailed mechanisms remain obscure. In this study, tert-butylhydroperoxide (t-BHP) was used to induce oxidative stress on differentiated C2C12 myotubes. t-BHP induced significant mitochondrial dysfunction in a time-dependent manner, accompanied by decreased myosin heavy chain (MyHC) expression at both the mRNA and protein levels. Consistently, endogenous reactive oxygen species (ROS) overproduction triggered by carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone (FCCP), a mitochondrial oxidative phosphorylation inhibitor, was accompanied by decreased membrane potential and decreased MyHC protein content. However, the free radical scavenger N-acetyl-L-cysteine (NAC) efficiently reduced the ROS level and restored MyHC content, suggesting a close association between ROS and MyHC expression. Meanwhile, we found that both t-BHP and FCCP promoted the cleavage of optic atrophy 1 (OPA1) from the long form into short form during the early stages. In addition, the ATPase family gene 3-like 2, a mitochondrial inner membrane protease, was also markedly increased. Moreover, OPA1 knockdown in myotubes was accompanied by decreased MyHC content, whereas NAC failed to prevent FCCP-induced MyHC decrease with OPA1 knockdown, suggesting that ROS might affect MyHC content by modulating OPA1 cleavage. In addition, hydroxytyrosol acetate (HT-AC), an important compound in virgin olive oil, could significantly prevent t-BHP-induced mitochondrial membrane potential and cell viability loss in myotubes. Specifically, HT-AC inhibited t-BHP-induced OPA1 cleavage and mitochondrial morphology changes, accompanied by improvement on mitochondrial oxygen consumption capacity, ATP productive potential and activities of mitochondrial complex I, II and V. Moreover, both t-BHP- and FCCP-induced MyHC decrease was sufficiently inhibited by HT-AC. Taken together, our data provide evidence indicating that mitochondrial dysfunction-associated OPA1 cleavage may contribute to muscle degeneration, and olive oil compounds could be effective nutrients for preventing the development of muscle disorders.
Ion antiport accelerates photosynthetic acclimation in fluctuating light environments
Authors: Armbruster Ute , Carrillo L. Ruby , Venema Kees , Pavlovic Lazar , Schmidtmann Elisabeth , Kornfeld Ari , Jahns Peter , Berry Joseph A. , Kramer David M. , Jonikas Martin C.
Published: November 2014

Many photosynthetic organisms globally, including crops, forests and algae, must grow in environments where the availability of light energy fluctuates dramatically. How photosynthesis maintains high efficiency despite such fluctuations in its energy source remains poorly understood. Here we show that Arabidopsis thaliana K+ efflux antiporter (KEA3) is critical for high photosynthetic efficiency under fluctuating light. On a shift from dark to low light, or high to low light, kea3 mutants show prolonged dissipation of absorbed light energy as heat. KEA3 localizes to the thylakoid membrane, and allows proton efflux from the thylakoid lumen by proton/potassium antiport. KEA3’s activity accelerates the downregulation of pH-dependent energy dissipation after transitions to low light, leading to faster recovery of high photosystem II quantum efficiency and increased CO2 assimilation. Our results reveal a mechanism that increases the efficiency of photosynthesis under fluctuating light.
Theoretical design of multi-colored semi-transparent organic solar cells with both efficient color filtering and light harvesting
Authors: Wen Long , Chen Qin , Sun Fuhe , Song Shichao , Jin Lin , Yu Yan
Published: November 2014

Solar cells incorporated with multi-coloring capability not only offer an aesthetic solution to bridge the gap between solar modules and building decorations but also open up the possibility for self-powered colorful display. In this paper, we proposed a multi-colored semi-transparent organic solar cells (TOSCs) design containing metallic nanostructures with the both high color purity and efficiency based on theoretical considerations. By employing guided mode resonance effect, the multi-colored TOSC behave like an efficient color filter that selectively transmits light with the desired wavelengths and generates electricity with light of other wavelengths. Broad range of coloring and luminosity adjusting for the transmission light can be achieved by simply tuning the period and the duty cycle of the metallic nanostructures. Furthermore, accompanying with the efficient color filtering characteristics, the optical absorption of TOSCs was improved due to the marked suppression of transmission loss at the off-resonance wavelengths and the increased light trapping in TOSCs. The mechanisms of the light guiding in photoactive layer and broadband backward scattering from the metallic nanostructures were identified to make an essential contribution to the improved light-harvesting. By enabling efficient color control and high efficiency simultaneously, this approach holds great promise for future versatile photovoltaic energy utilization.
“Grain for Green” driven land use change and carbon sequestration on the Loess Plateau, China
Authors: Deng Lei , Shangguan Zhou-ping , Sweeney Sandra
Published: November 2014

Land-use change is widely considered to be a major factor affecting soil carbon (C) sequestration (ΔCs). This paper studied changes to soil C stocks (Cs) following the conversion of farmland to forest, shrub and grassland across the key area for implementing China's “Grain for Green” — the Loess Plateau. The results are based on a synthesis of 44 recent publications (including 424 observations at 70 sites) which has allowed us to further refine our understanding of the mechanisms driving the increase in Cs following farmland conversion. This synthesis suggests that the ΔCs potential of the Loess Plateau could reach 0.59 Tg yr−1 based on an estimated annual average ΔCs rate of 0.29 Mg ha−1 yr−1. In the region's different rainfall zones both the main contributing factors and Cs dynamics varied. Across the entire Loess Plateau, Cs showed first an increasing (<5 yr) then a decreasing (6–10 yr) tendency only to increase (>10 yr) yet again. In addition, the ΔCs rates depended primarily on restoration age. This synthesis demonstrates that both the initial s Cs and the average annual temperature have a significant effect on ΔCs while the effect of land-use conversion type, rainfall zone and average annual precipitation were minimal.
Hydrodeoxygenation of Biomass-Derived Liquids over Transition-Metal-Sulfide Catalysts
Authors: Pawelec Barbara , Garcia Fierro Jose Luis
Published: November 2014

Bio-oil production through flash pyrolysis of biomass has been identified as one of the most feasible routes for the production of renewable fuels, as these biomass-derived liquids possess high oxygen content, and therefore, low stability over time as well as a low heating value. Upgrading is needed to decrease the oxygen content, and thus render a product resembling crude oil. One of the general routes for bio-oil upgrading is hydrodeoxygenation (HDO), a high-pressure operation in which hydrogen is used to exclude the oxygen functionalities from the bio-oil, giving a high-grade oil product equivalent to crude oil. Catalysts for the reaction are traditionally hydrodesulfurization (HDS) catalysts, such as CoMo sulfides. However, catalyst lifetimes of more than 200 h have not been achieved with any of the current catalysts due to carbon deposition. So far, two main routes have been proposed, considering many studies on the laboratory-scale and others from industry: catalytic hydrotreatment (HDT), mainly by hydrodeoxygenation (HDO), and catalytic cracking, technologies that are already present in today's refinery configurations. HDO has been performed at high hydrogen pressure, using catalysts based on those typically applied in conventional hydrotreating. This chapter focuses on the upgrading possibilities of renewable feedstocks, obtained from biomass fast pyrolysis or nonedible oils, towards the production of second-generation biofuels. It also includes some recent studies concerning the coprocessing of bio-oils together with petroleum. In fact, although all these raw materials have the potential to be directly converted into transportation fuels in dedicated units, it seems more attractive to upgrade them in combination with conventional oil feeds.
Reactor Technology and Modeling Aspects for the Hydrogenation of Components from Biomass
Authors: Kilpiö Teuvo , Sifontes Victor , Eränen Kari , Murzin Dmitry Yu. , Salmi Tapio
Published: November 2014

Catalyst concepts, reaction kinetics, transport phenomena, and reactor technology for hydrogenation of monosaccharides to sugar alcohols are addressed. The chapter highlights the pathway paved from green chemistry towards green process technology. Typically, the catalyst development and screening in addition to kinetic experiments are carried out in batch and semibatch reactors. However, the final goal of a sustainable process is associated with the performance characteristics of fixed-bed reactors. As such, the continuous reactor technology plays a fundamental role in establishing selective and efficient processes for the production of useful molecules from renewable sources. This chapter gives an overview of the important issues that should be considered during scaling up of monosaccharides hydrogenation from batch to continuous mode.
Structure-dynamic determinants governing a mode of regulatory response and propagation of allosteric signal in splice variants of Na+/Ca2+ exchange (NCX) proteins
Authors: Giladi Moshe , Lee Su Youn , Hiller Reuben , Chung Ka Young , Khananshvili Daniel
Published: November 2014

The Ca2+-dependent allosteric regulation of Na+/Ca2+ exchanger (NCX) proteins represents Ca2+ interaction with the cytosolic domains, CBD1 (calcium-binding domain 1) and CBD2, which is associated either with activation, inhibition or no response to regulatory Ca2+ in a given splice variant. CBD1 contains a high affinity Ca2+-sensor (which is highly conserved among splice variants), whereas primary information upon Ca2+ binding to CBD1 is modified by alternative splicing of CBD2, yielding the diverse regulatory responses to Ca2+. To resolve the structure-dynamic determinants of splicing-dependent regulation, we tested two-domain tandem (CBD12) constructs possessing either positive, negative or no response to Ca2+ using hydrogen–deuterium exchange MS (HDX–MS), SAXS, equilibrium 45Ca2+ binding and stopped-flow kinetics. Taken together with previously resolved crystallographic structures of CBD12, the data revealed that Ca2+ binding to CBD1 rigidifies the main-chain flexibility of CBD2 (but not of CBD1), whereas CBD2 stabilizes the apo-CBD1. Strikingly, the extent and strength of Ca2+-dependent rigidification of CBD2 is splice-variant dependent, where the main-chain rigidification spans from the Ca2+-binding sites of CBD1, through a helix of CBD2 (positioned at the domains’ interface) up to the tip of CBD2 [>50 Å (1 Å=0.1 nm)] or alternatively, it stops at the CBD2 helix in the splice variant exhibiting an inhibitory response to regulatory Ca2+. These results provide a structure-dynamic basis by which alternative splicing diversifies the regulatory responses to Ca2+ as well as controls the extent and strength of allosteric signal propagation over long distance.
Hydrogen sulfide: an old gas with new cardioprotective effects
Authors: Patel Vaibhav B. , McLean Brent A. , Chen Xueyi , Oudit Gavin Y.
Published: November 2014

Diabetic cardiovascular complications are reaching epidemic proportions and the risk of HF (heart failure) is increased 2–3-fold by diabetes mellitus. H2S (hydrogen sulfide) is emerging as a new gaseous signalling molecule in the cardiovascular system which possesses multifactorial effects on various intracellular signalling pathways. The proven cardioprotective and vasodilator activities of H2S warrant a detailed investigation into its role in diabetic cardiomyopathy. In the present issue of Clinical Science, Zhou et al. demonstrate an important therapeutic potential of the H2S pathway in diabetic cardiomyopathy.
4H‐SiC work‐function‐dependent bipolar transistor with ultra‐high current gain
Authors: Yuan Lei , Zhang Yuming , Song Qingwen , Tang Xiaoyan , Zhang Yimen
Published: November 2014

A new structure of a 4H‐SiC bipolar transistor with ultra‐high current gain is proposed and analysed by simulation. A p‐type Schottky contact serving as the conventional emitter region is introduced. By proper choice of the metal work‐function, the injection efficiency of the minority carrier (electron) is promoted and may be close to unity. Therefore high current gain is realised due to the high electron current density injected from the p‐type Schottky contact. The simulation results show that the current gain varies with the metal work‐function and could reach ∼1000, which is attractive for the base‐drive circuit. Moreover, the new structure simplifies the etching process compared with the conventional bipolar junction transistor.
Power‐efficient pre‐emphasis method for transmitters with LVDS drivers
Authors: Wang Yang , Gai Weixin
Published: November 2014

A 65 nm CMOS 20 Gb/s transmitter with a low‐voltage differential signalling (LVDS) driver is presented. A novel power‐efficient pre‐emphasis method that eliminates power wasting in conventional pre‐emphasis is proposed. The input to the driver is pre‐coded so that the pre‐emphasis taps only inject current to the output nodes upon voltage level transition of the output signal. Current does not flow through the pre‐emphasis taps when there is no transition. Simulation results show that the proposed pre‐emphasis achieves the same output waveform and pre‐emphasis capability as the conventional approach while consuming less power.
Portable true random number generator for personal encryption application based on smartphone camera
Authors: Zhang Xuping , Qi Li , Tang Zhiqiang , Zhang Yixin
Published: November 2014

The true random number generator (TRNG) is an invaluable resource for many applications. Present TRNG methods all require specialised and expensive hardware, which are not suitable for personal use. A portable TRNG configuration is proposed, which is simply based on the camera of a commercial smartphone. No other auxiliary equipment except the mobile phone itself was needed, which offers a promising solution for personal encryption applications. With the flash lamp of the camera and the thumb of the operator, quasi‐uniform illumination was obtained, setting the image sensor at a working point where the shot noise of the photocurrent dominates the overall characteristics of the sensor output noise. Random bits were first produced according to the shot noise and then entropy enhanced by vector–matrix multiplication. A sequence of 109 bits was produced and its randomness has been proved by the National Institute of Standards and Technology (NIST) tests.
Omnidirectional rectangular microstrip antenna operating at TM02 and TM20 modes for mobile applications
Authors: Zou Meng , Pan Jin , Zuo Le , Nie Zaiping
Published: November 2014

A simple rectangular microstrip antenna with an omnidirectional conical beam pattern (OCBP) is proposed. The higher‐order TM02 and TM20 modes are excited in phase and with equal amplitude by two probes to generate an omnidirectional pattern. The method to suppress mutual coupling between the two ports is introduced. A prototype antenna is designed, fabricated and measured, and the measured results agree well with the simulated results. The proposed antenna has an omnidirectional pattern in the azimuth plane and peaks at an elevation of 55°. The OCBP of the proposed antenna makes it very suitable for mobile communication systems.
2.56 GHz sub‐harmonically injection‐locked PLL with cascaded DLL for multi‐phase injection
Authors: Choi Changsung , Hwang Sewook , Song Junyoung , Kim Chulwoo
Published: November 2014

A 2.56 GHz injection‐locked phase‐locked loop (ILPLL) cascaded with a delay‐locked loop (DLL) for minimising phase noise is presented. Generally, an ILPLL includes an injection‐locked voltage‐controlled oscillator (ILVCO), which is directly injected with the reference clock phase. However, the proposed scheme connects the output multi‐phased clocks of the DLL to the injection node and they can be selected with turn on/off switches. This can shorten the realignment time of the VCO phases and thus the in‐band phase noise is decreased. The proposed circuit is implemented in a 65 nm CMOS technology, and reduces the phase noise by 10.86 dBc/Hz at a 1 MHz offset with 16 multi‐phased injections, compared with a conventional PLL.
Small oxide‐free vertical‐cavity surface‐emitting lasers with high efficiency and high power
Authors: Yang Xu , Li Ming Xin , Zhao Guowei , Freisem Sabine , Deppe Dennis G.
Published: November 2014

Data are presented showing high external differential quantum efficiency (DQE) and record‐high output power in vertical‐cavity surface‐emitting lasers (VCSELs) with diameters below 3 µm. Good uniformity and reproducibility are achieved in devices with very small sizes. Over 75% DQEs are measured with maximum output powers of 5, 7.3, 8, 8.7 and 11.6 mW for 1, 1.5, 2, 2.5 and 3 µm diameter VCSELs, respectively.
Reducing false conflicts in signature‐based eager hardware transactional memory
Authors: Kang Jinku , Jung Jaeil , Lee Inhwan
Published: November 2014

The use of a conflict‐address buffer (CAB) for reducing false conflicts in signature‐based eager hardware transactional memory (HTM) is proposed. On the basis of the observation that most conflicts occur when accessing a very small set of addresses, the CAB captures those addresses that generate a conflict at runtime and performs more precise conflict detection for the captured addresses. Using the CAB can reduce false conflicts and the associated unnecessary transaction aborts and, consequently, improve the performance of the multicore processors that implement the signature‐based eager HTM. When running the Stanford transactional applications for multiprocessing (STAMP) benchmark on a 16‐core processor that implements the LogTM‐SE, the speedup (decrease in execution time) achieved with a 4‐entry CAB is 9.4% on average.
Enhancement of specific heat of ternary nitrate (LiNO3‐NaNO3‐KNO3) salt by doping with SiO2 nanoparticles for solar thermal energy storage
Authors: Seo Joohyun , Shin Donghyun
Published: November 2014

An enhancement of specific heat in a ternary molten nitrate salt eutectic doped with nanoparticles at a minute concentration is reported. SiO2 nanoparticles, whose nominal size is 60 nm, were doped into a ternary nitrate molten salt eutectic (LiNO3‐NaNO3‐KNO3) at 1% concentration by weight. A modulated differential scanning calorimeter was employed to characterise the specific heat of the eutectic mixture. According to a density weighted specific heat model, the effective specific heat of the mixture should not significantly change since the concentration of the nanoparticles is very small. However, the specific heat of the mixture of eutectic and nanoparticles was enhanced by 13%. From a subsequent material characterisation, a large amount of fractal‐like nanostructure formation by the eutectic near embedded SiO2 nanoparticles was observed. The nanostructure has a very large specific surface area as have the embedded SiO2 nanoparticles. This can significantly amplify the effect of surface energy on the effective specific heat and is thus responsible for the enhanced specific heat of the mixture. Using the ternary molten salt eutectic with enhanced specific heat for thermal energy storage can significantly increase the energy storage efficiency and thus reduce the cost of electricity in a concentrated solar power system.
Preparation of heat resisting poly(methyl methacrylate)/silica fume composite microspheres used as ultra‐lightweight proppants
Authors: Chen Tao , Wang Yixia , Yan Chunjie
Published: November 2014

Ultra‐lightweight heat resisting poly(methyl methacrylate) (PMMA)/silica fume microspheres were successfully prepared via in‐situ suspension polymerisation. Scanning electron microscopy indicated that PMMA/silica fume composite microspheres had good sphericity and the silica fume particles were evenly dispersed in microspheres and formed lots of macroporous material. Furthermore, density analysis illustrated that the density of composites was about 1.06–1.24 g/cm3 with good suitability for water carrying. Thermal stability of the PMMA/silica fume composite particles was significantly better than pure for PMMA. Therefore, PMMA/silica fume composite microspheres possess an entirely feasible application in oil exploitation as ultra‐lightweight proppants.
The slingshot effect: A possible new laser-driven high energy acceleration mechanism for electrons
Authors: Fiore Gaetano , Fedele Renato , de Angelis Umberto
Published: November 2014

We show that under appropriate conditions the impact of a very short and intense laser pulse onto a plasma causes the expulsion of surface electrons with high energy in the direction opposite to the one of the propagations of the pulse. This is due to the combined effects of the ponderomotive force and the huge longitudinal field arising from charge separation (“slingshot effect”). The effect should also be present with other states of matter, provided the pulse is sufficiently intense to locally cause complete ionization. An experimental test seems to be feasible and, if confirmed, would provide a new extraction and acceleration mechanism for electrons, alternative to traditional radio-frequency-based or laser-wake-field ones.
Large strain response based on relaxor-antiferroelectric coherence in Bi0.5Na0.5TiO3–SrTiO3–(K0.5Na0.5)NbO3 solid solutions
Authors: Liu Laijun , Shi Danping , Knapp Michael , Ehrenberg Helmut , Fang Liang , Chen Jun
Published: November 2014

The effect of (K0.5Na0.5)NbO3 (KNN) addition on the ferroelectric and dielectric behavior of 90Bi0.5Na0.5TiO3–10SrTiO3 (BNT–ST) lead-free piezoceramics was investigated. Polarization and strain hysteresis loops indicate that a relaxor-antiferroelectric coherence will be produced with the addition of KNN as a replacement for ST up to 5% and the destabilization of the phase coherence is accompanied by an enhancement of the bipolar strain with the increase of temperature, which is ∼0.37% (corresponding to a large signal d33* of ∼530 pm/V at 90 °C) at 5 mol. % KNN content. This strain was analyzed as derived from an electrostrictive effect at lower electric fields and a field-induced antiferroelectric-ferroelectric phase transition at higher electric fields. The large polar strain response would be of great interest for environmental friendly high-temperature actuators.
Experimental determination of the dynamics of an acoustically levitated sphere
Authors: Pérez Nicolás , Andrade Marco A. B. , Canetti Rafael , Adamowski Julio C.
Published: November 2014

Levitation of solids and liquids by ultrasonic standing waves is a promising technique to manipulate materials without contact. When a small particle is introduced in certain areas of a standing wave field, the acoustic radiation force pushes the particle to the pressure node. This movement is followed by oscillations of the levitated particle. Aiming to investigate the particle oscillations in acoustic levitation, this paper presents the experimental and numerical characterization of the dynamic behavior of a levitated sphere. To obtain the experimental response, a small sphere is lifted by the acoustic radiation force. After the sphere lift, it presents a damped oscillatory behavior, which is recorded by a high speed camera. To model this behavior, a mass-spring-damper system is proposed. In this model, the acoustic radiation force that acts on the sphere is theoretically predicted by the Gor'kov theory and the viscous forces are modeled by two damping terms, one term proportional to the square of the velocity and another term proportional to the particle velocity. The proposed model was experimentally verified by using different values of sound pressure amplitude. The comparison between numerical and experimental results shows that the model can accurately describe the oscillatory behavior of the sphere in an acoustic levitator.
Tuning the plasmon band number of aluminum nanorod within the ultraviolet-visible region by gold coating
Authors: Zhu Jian , Li Jian-Jun , Zhao Jun-Wu
Published: November 2014

The localized surface plasmon (LSP) properties of Al nanorod with Au coating have been investigated by using the quasi-static calculation. Because of the anisotropic plasmon splitting and the plasmon coupling between the Al and Au surfaces, the band number of LSP in the Al-Au core-shell nanorod could be tuned from 2 to 4 continuously in the ultraviolet-visible region. Due to the non-spherical symmetry and the dielectric polarization-induced plasmon energy fading, the Au coating-dependent plasmon shift and split are further affected by the aspect ratio and the dielectric surrounding. When the aspect ratio or the surrounding dielectric constant has a small value, the band number of LSP could only be tuned from 2 to 3. However, the band number of LSP could only be tuned from 3 to 4 when the aspect ratio or the surrounding dielectric constant has a large value. This tunable band number of LSP in the Au-coated Al nanorod provides potential application for multichannel plasmonic nanosensors.
Hard magnetic property enhancement of Co7Hf-based ribbons by boron doping
Authors: Chang H. W. , Liao M. C. , Shih C. W. , Chang W. C. , Yang C. C. , Hsiao C. H. , Ouyang H.
Published: November 2014

Hard magnetic property enhancement of melt spun Co88Hf12 ribbons by boron doping is demonstrated. B-doping could not only remarkably enhance the magnetic properties from energy product ((BH)max) of 2.6 MGOe and intrinsic coercivity (iHc) of 1.5 kOe for B-free Co88Hf12 ribbons to (BH)max = 7.7 MGOe and iHc = 3.1 kOe for Co85Hf12B3 ribbons but also improve the Curie temperature (TC) of 7:1 phase. The (BH)max value achieved in Co85Hf12B3 ribbons is the highest in Co-Hf alloy ribbons ever reported, which is about 15% higher than that of Co11Hf2B ribbons spun at 16 m/s [M. A. McGuire, O. Rios, N. J. Ghimire, and M. Koehler, Appl. Phys. Lett. 101, 202401 (2012)]. The structural analysis confirms that B enters the orthorhombic Co7Hf (7:1) crystal structure as interstitial atoms, forming Co7HfBx, in the as-spun state. Yet B may diffuse out from the 7:1 phase after post-annealing, leading to the reduction of Curie temperature and the magnetic properties. The uniformly refined microstructure with B-doping results in high remanence (Br) and improves the squareness of demagnetization curve. The formation of interstitial-atom-modified Co7HfBx phase and the microstructure refinement are the main reasons to give rise to the enhancement of hard magnetic properties in the B-containing Co7Hf-based ribbons.
Self-organized patterns along sidewalls of iron silicide nanowires on Si(110) and their origin
Authors: Das Debolina , Mahato J. C. , Bisi Bhaskar , Satpati B. , Dev B. N.
Published: November 2014

Iron silicide (cubic FeSi2) nanowires have been grown on Si(110) by reactive deposition epitaxy and investigated by scanning tunneling microscopy and scanning/transmission electron microscopy. On an otherwise uniform nanowire, a semi-periodic pattern along the edges of FeSi2 nanowires has been discovered. The origin of such growth patterns has been traced to initial growth of silicide nanodots with a pyramidal Si base at the chevron-like atomic arrangement of a clean reconstructed Si(110) surface. The pyramidal base evolves into a comb-like structure along the edges of the nanowires. This causes the semi-periodic structure of the iron silicide nanowires along their edges.
Strain redistribution in free-standing bridge structure released from strained silicon-on-insulator
Authors: Sun Gaodi , Zhang Miao , Xue Zhongying , Guo Qinglei , Chen Da , Mu Zhiqiang , Dong Linxi , Wang Xi , Di Zengfeng
Published: November 2014

The strain evolution including relaxation and conversion during the fabrication of free-standing bridge structure, which is the building block for the gate-all-around transistor, has been investigated in strained silicon-on-insulator. Compared to the starting strained silicon-on-insulator substrate, the strain of the free-standing bridge structure transforms from the biaxial strain to the uniaxial strain after patterning and release due to its unique configuration, as suggested by UV-Raman spectroscopy. Furthermore, such uniaxial strain has strong correlation with the dimension of the suspended structure, and it is enhanced as the width of the free-standing bridge decreases and the size of the connected pad increases. For 0.5μm-wide free-standing bridge connected to the pad of 16 × 16 μm2, the maximum uniaxial tensile strain of 4.65% is obtained, which remarkably exceeds the levels that can be achieved by other techniques ever reported. The observed strain redistribution phenomenon is also analyzed by two-dimensional finite element modeling. The finite element modeling confirms the strain evolution in the suspended bridge structure after patterning and release, in agreement with the experimental observations.
Evaluation of a nurse practitioner-led extended hours mental health liaison nurse service based in the emergency department
Authors: Wand Timothy , D'Abrew Natalie , Barnett Catherine , Acret Louise , White Kathryn
Published: November 2014

Objective
To evaluate a nurse practitioner (NP)-led extended hours mental health liaison nurse (MHLN) service based in the emergency department (ED) of an inner city teaching hospital in Sydney and to explicate a model of care that is transferable across a broad range of ED settings, both in metropolitan and rural contexts.

Methods
This mixed-methods evaluation encompassed descriptive data on ED mental health presentations, quantifying waiting times for MHLN involvement and interviews with MHLN team members at the commencement of the evaluation and 12 months later. Interviews were also conducted with a snapshot of ED patients, and a sample of ED and psychiatry staff.

Results
The expanded MHLN service was rapidly incorporated into the ED structure, enthusiastically endorsed by ED patients and highly valued by staff and the organisation. The MHLN team saw 55% of referred patients within the first hour of arrival (frequently before medical assessment), thereby initiating and expediting co-ordination of care at an early stage of the ED process.

Conclusions
An NP-led extended hours MHLN team based in the ED provides prompt and effective access to specialised mental health care for people with ‘undifferentiated health problems’, and removes a significant workload from nursing and medical staff. Embedding the NP-led MHLN service within the ED structure was pivotal to the success and sustainability of this model of care.

What is known about the topic?
Mental health liaison nurse (MHLN) services have existed in emergency departments (EDs) in Australia and internationally for many years. However, there is great variation in the way these services are structured and no standardised model of care has been explicated.

What does this paper add?
Findings from this evaluation indicate that a nurse practitioner-led extended hours MHLN service integrated within the ED team structure provides prompt access to specialised mental health care to people with undifferentiated health problems, and removes a significant workload from ED nursing and medical staff.

What are the implications for practitioners?
Mental health nurse-led service provision based in the ED is a safe, flexible and effective method of enhancing access to health care that is adaptable to broad range of settings. ED ownership of this model of care is pivotal to the successful implementation and sustainability of MHLN services.
Integrative taxonomy of Acrapex stem borers (Lepidoptera : Noctuidae : Apameini): combining morphology and Poisson Tree Process analyses
Authors: Le Ru Bruno P. , Capdevielle-Dulac Claire , Toussaint Emmanuel F. A. , Conlong Desmond , Van den Berg Johnnie , Pallangyo Beatrice , Ong'amo George , Chipabika Gilson , Molo Richard , Overholt William A. , Cuda James P. , Kergoat Gael J.
Published: November 2014

Ten morphologically similar species of Acrapex from eastern and south-eastern Africa belonging to the A. stygiata and A. albivena groups are reviewed. Six species are described as new: A. brunneella, A. mitiwa, A. mpika, A. salmona, A. sporobola and A. yakoba. The Poaceae host plants of eight species are recorded; four species, A. mitiwa. A. subalbissima, A. syscia and A. yakoba, were found developing exclusively on Imperata cylindrica (L.) Beauv., (Andropogoneae); two species, A. sporobola and A. salmona, on I. cylindrica and Sporobolus macranthelus Chiov. (Zoysieae); and A. albivena on I. cylindrica, Miscanthus capensis (Nees) Andersson (Andropogoneae) and Cymbopogon sp. (Andropogoneae). Acrapex stygiata larvae developed on M. capensis and Cymbopogon sp. The host plants of A. brunneella and A. mpika remain unknown. We also conducted molecular phylogenetics and molecular species delimitation analyses on a comprehensive sample of 49 specimens belonging to nine of the studied species. Molecular phylogenetics and molecular species delimitation analyses provided additional evidence of the validity of the six newly described species but also suggested a level of hidden biodiversity for one of them.
Systematics and host plant associations of a new genus of Acacia-inhabiting plant bugs from arid Australia (Insecta : Hemiptera : Heteroptera : Miridae : Orthotylinae)
Authors: Cassis Gerasimos , Symonds Celia
Published: November 2014

Acaciacapsus, gen. nov. is described as a new plant bug genus, with eight new included species: A. amadeus, sp. nov.; A. appha, sp. nov.; A. aureolus, sp. nov.; A. bournda, sp. nov.; A. emeraldensis, sp. nov.; A. lolworthensis, sp. nov.; A. millstreamensis, sp. nov.; and A. woodwardi, sp. nov. Differential diagnoses and descriptions are given for all species, including salient characters, and the male and female genitalia. An identification key is provided to species. Male genitalia are illustrated, and a habitus photograph is provided for each species. Female genitalia are illustrated for two species. The genus is putatively an Acacia specialist, and has cryptozoic yellowish colouration. The species are primarily found in arid and semi-arid regions of non-monsoonal regions of Australia. The collection events are digitised and their distributions mapped. A phylogeny of species is given. Modifications are given to male genitalic homologies and are discussed in reference to other Australian orthotylines.
Verification of the cryptic species Penaeus pulchricaudatus in the commercially important kuruma shrimp P. japonicus (Decapoda : Penaeidae) using molecular taxonomy
Authors: Tsoi K. H. , Ma K. Y. , Wu T. H. , Fennessy S. T. , Chu K. H. , Chan T. Y.
Published: November 2014

The kuruma shrimp Penaeus japonicus Bate, 1888 (Decapoda : Penaeidae) is economically important in the global shrimp market. It was regarded as the only species in the subgenus Marsupenaeus. However, our previous molecular analyses revealed two cryptic species (Forms I and II) in this species complex. In this study, we confirm the phylogenetic relatedness between the two cryptic species; revise their taxonomic status; and review their range distribution. The name Penaeus pulchricaudatus Stebbing, 1914 (with type-locality off the eastern coast of South Africa), previously considered as a junior synonym of P. japonicus, is fixed for Form II through a neotype selection. P. japonicus (Form I) is only confined to the East China Sea (including Japan, its type-locality) and the northern South China Sea. P. pulchricaudatus is widely distributed in the South China Sea, Australia, the Red Sea, the Mediterranean, and the western Indian Ocean. Phylogenetic analysis shows that P. japonicus is genetically homogeneous yet P. pulchricaudatus exhibits a strong phylogeographical structure. The Mediterranean stock of P. pulchricaudatus originated from the Red Sea population, supporting the Lessepsian migration hypothesis. The presence of two closely related cryptic species in the P. japonicus species complex provides important insights into fishery management and aquaculture development.
Mutagenicity and tumor-promoting effects of Tiglium seed extract via PKC and MAPK signaling pathways
Authors: Kim Ji-Young , Yun Jun-Won , Kim Yun-Soon , Kwon Euna , Choi Hyung Jun , Yeom Su-Cheong , Kang Byeong-Cheol
Published: November 2014

Tiglium seed is a seed of mature Croton Tiglium Linne containing croton oils, which have been traditionally used as laxative or purgative. As it contains phorbol derivatives, we investigated the mutagenicity and tumor-promoting activity of Tiglium seed. Tiglium seed extract produced the mutagenic responses in five Salmonella typhimurium strains in Ames assay, whereas it did not alter the frequencies of chromosomal aberrations or micronuclei, indicating that it exerted the mutagenic potential, not clastogenicity. Accompanied with phosphorylation of connexin43 (Cx43) and extracellular signal-regulated kinases 1/2 (ERK1/2), Tiglium seed extract inhibited gap junctional intercellular communication (GJIC) associated with tumor-promoting potential. Importantly, these effects were blocked by a protein kinase C (PKC) inhibitor or mitogen-activated protein kinase (MAPKs) inhibitors, suggesting that Tiglium seed-induced GJIC inhibition was regulated by phosphorylation of Cx43 via PKC and MAPKs signaling. In conclusion, Tiglium seed has mutagenicity, possibly linking to tumor-promoting potential through the dysfunction of GJIC.
Aroma compounds in Japanese sweet rice wine (Mirin) screened by aroma extract dilution analysis (AEDA)
Authors: Kaneko Shu , Kumazawa Kenji
Published: November 2014

Thirty-nine key aroma compounds were newly identified or tentatively identified in the aroma concentrate of Japanese sweet rice wine (Mirin) by an aroma extract dilution analysis technique based on the 68 detected peaks. Among them, 3-(methylthio)propanal, 3-hydroxy-4,5-dimethyl-2(5H)-furanone, 3-methylbutanoic acid, 2-methylbutanoic acid, and 2-methoxy-4-vinylphenol were detected with the highest FD factors in this study.
Examining the benefits of collaboration: the Provider-User Matrix for collaborative flood risk management illustrated by the case of the Ljusnan River, Sweden
Authors: Hedelin Beatrice , Hjerpe Mattias
Published: November 2014

This paper examines the benefits of collaboration in flood risk management by introducing a Provider-User Matrix. The matrix is illustrated through a Swedish case of polycentric decision-making. In the Swedish case the users have not yet benefited from collaboration-benefits such as a more advanced understanding of the flood response system or from sharing detailed hydrological data; benefits that should be easily implemented. The Provider-User Matrix offers both a more holistic way to study benefits and a way to start raising the efficiency of collaboration, by identifying mismatches between the benefits provided and the benefits that users need.