bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of a colorimetric method to determine trace urea in seawater
Authors: Chen Li , Ma Jian , Huang Yang , Dai Minhan , Li Xiaolin
Published: May 2015

This study optimized the experimental conditions for the analysis of dissolved urea in seawater. The kinetics of the colorimetric reaction of urea with diacetyl monoxime were studied under different conditions: reagent stability, pH, and reaction temperature and time, based on which robust procedures were developed for both normal (> 100 nmol L−1, using a five centimeter cuvette) and trace (<100 nmol L−1, using a one meter path length capillary cell) levels of dissolved urea. Our trace level method showed very high sensitivity (detection limit of 1.2 nmol L−1) and high reproducibility (relative standard deviations were 0.29–1.09%), which was a significant improvement as compared to what was reported previously. The current method afforded a more stable colorimetric product, which provided better reproducibility when a large number of samples were analyzed. The normal‐level method was applied to studying the urea distribution in estuarine surface water, and the trace‐level method was applied to studying the vertical distribution of urea in the South China Sea basin (> 4000 m).
Assessment of the radio 3H‐CH4 tracer technique to measure aerobic methane oxidation in the water column
Authors: Bussmann Ingeborg , Matousu Anna , Osudar Roman , Mau Susan
Published: May 2015

Microbial methane oxidation rates in ocean and freshwater systems reveal how much of emitted methane from the sediments is oxidized to CO2 and how much can reach the atmosphere directly. The tracer‐method using 3H‐CH4 provides a way to measure methane oxidation rates even in water with low methane concentrations. We assessed this method by implementing several experiments, collecting data from various environments, and including recent literature concerning the method to identify any uncertainties that should be considered. Our assessment reveals some difficulties of the method but also reassures previous assumptions to be correct. Some of the difficulties are hardly to be avoided, such as incubating all samples at the right in situ temperature or limiting the variability of methane oxidation rate measurements in water of low methanotrophic activity. Other details, for example, quickly measuring the total radioactivity after stopping the incubation, are easy to adapt in each laboratory. And yet other details as shaking during incubation and bottle size seem to be irrelevant. With our study, we hope to improve and to encourage future measurements of methane oxidation rates in different environments and to provide a standard procedure of methane oxidation rate measurements to make the data better comparable.
Alkaline‐extractable silicon from land to ocean: A challenge for biogenic silicon determination
Authors: Barão Lúcia , Vandevenne Floor , Clymans Wim , Frings Patrick , Ragueneau Olivier , Meire Patrick , Conley Daniel J. , Struyf Eric
Published: May 2015

The biogeochemical cycling of silicon (Si) along the land‐to‐ocean continuum is studied by a variety of research fields and for a variety of scientific reasons. However, there is an increasing need to refine the methodology and the underlying assumptions used to determine biogenic silica (BSi) concentrations. Recent evidence suggests that contributions of nonbiogenic sources of Si dissolving during alkaline extractions, not corrected by standard silicate mineral dissolution correction protocols, can be substantial. The ratio between dissolved Si and aluminum (Al) monitored continuously during the alkaline extraction can be used to infer the origin of the Si fractions present. In this study, we applied both a continuous analysis method (0.5 M NaOH) and a traditional 0.1 M Na2CO3 extraction to a wide array of samples: (1) terrestrial vegetation, (2) soils from forest, cropland and pasture, (3) lake sediments, (4) suspended particulate matter and sediments from rivers, (5) sediments from estuaries and salt marshes and (6) ocean sediments. Our results indicate that the 0.1 M Na2CO3 extraction protocol can overestimate the BSi content, by simultaneously dissolving Si fractions of nonbiogenic origin that may represent up to 100% of the Si traditionally considered as biogenic, hampering interpretation especially in some deeper soil horizons, rivers and coastal oceanic sediments. Moreover, although the term amorphous Si was coined to reflect a growing awareness of nonbiogenic phases we show it is actually inappropriate in samples where silicate minerals may account for a large part of the extracted Si even after linear mineral correction.
Physical Continuity and Vertical Alignment of Block Copolymer Domains by Kinetically Controlled Electrospray Deposition
Authors: Hu Hanqiong , Choo Youngwoo , Feng Xunda , Osuji Chinedum O.
Published: May 2015

The fabrication of block copolymer (BCP) thin films is reported with vertically aligned cylindrical domains using continuous electrospray deposition onto bare wafer surfaces. The out‐of‐plane orientation of hexagonally packed styrene cylinders is achieved in the “fast‐wet” deposition regime in which rapid evaporation of the solvent in deposited droplets of polymer solution drives the vertical alignment of the self‐assembled structure. Thermally activated crosslinking of the polybutadiene matrix provides kinetic control of the morphology, freezing the vertical alignment and preventing relaxation of the system to its preferred parallel orientation on the nontreated substrate. Physically continuous vertically oriented domains can be achieved over several micrometers of film thickness. The ability of electrospray deposition to fabricate well‐ordered and aligned BCP films on nontreated substrates, the low amount of material used relative to spin‐coating, and the continuous nature of the deposition may open up new opportunities for BCP thin films.

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Dual Sulfide–Disulfide Crosslinked Networks with Rapid and Room Temperature Self‐Healability
Authors: An So Young , Noh Seung Man , Nam Joon Hyun , Oh Jung Kwon
Published: May 2015

Polymer‐based crosslinked networks with intrinsic self‐repairing ability have emerged due to their built‐in ability to repair physical damages. Here, novel dual sulfide–disulfide crosslinked networks (s‐ssPxNs) are reported exhibiting rapid and room temperature self‐healability within seconds to minutes, with no extra healing agents and no change under any environmental conditions. The method to synthesize these self‐healable networks utilizes a combination of well‐known crosslinking chemistry: photoinduced thiol‐ene click‐type radical addition, generating lightly sulfide‐crosslinked polysulfide‐based networks with excess thiols, and their oxidation, creating dynamic disulfide crosslinkages to yield the dual s‐ssPxNs. The resulting s‐ssPxN networks show rapid self‐healing within 30 s to 30 min at room temperature, as well as self‐healing elasticity with reversible viscoelastic properties. These results, combined with tunable self‐healing kinetics, demonstrate the versatility of the method as a new means to synthesize smart multifunctional polymeric materials.

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Longitudinal assessment of spinal cord injuries in nonhuman primates with quantitative magnetization transfer
Authors: Wang Feng , Li Ke , Mishra Arabinda , Gochberg Daniel , Min Chen Li , Gore John C.
Published: May 2015

Purpose

This study aimed to evaluate the reproducibility and specificity of quantitative magnetization transfer (qMT) imaging for monitoring spinal cord injuries (SCIs).

Methods

MRI scans were performed in anesthetized monkeys at 9.4T, before and serially after a unilateral lesion of the cervical spinal cord. A two‐pool fitting model was used to derive qMT parameters.

Results

qMT measures were reproducible across normal subjects, with an average pool size ratio (PSR) of 0.086 ± 0.003 (mean ± SD) for gray matter, and 0.120 ± 0.005 for white matter, respectively. Compared with normal gray matter, the PSR of abnormal tissues rostral and caudal to the injury site decreased by 19.5% (P < 0.05), while the PSR of the cyst‐like volume decreased drastically weeks after SCI. Strong correlations in cyst‐like regions were observed between PSR and other MRI measures including longitudinal relaxation rate (R1), apparent diffusion coefficient and fractional anisotropy (FA). Decreased PSR and FA values correlated well with demyelination in abnormal tissues.

Conclusion

The qMT parameters provide robust and specific information about the molecular and cellular changes produced by SCI. PSR detected demyelination and loss of macromolecules in abnormal tissue regions rostral and caudal to the cyst/lesion sites. Magn Reson Med 75:1685–1696, 2016. © 2015 Wiley Periodicals, Inc.
Psychological factors at early stage of treatment as predictors of receiving chemotherapy at the end of life
Authors: Fujisawa Daisuke , Temel Jennifer S. , Traeger Lara , Greer Joseph A. , Lennes Inga T. , Mimura Masaru , Pirl William F.
Published: May 2015

Introduction

Administration of chemotherapy in the last 14 days of life is a widely recognized indicator of poor end‐of‐life (EOL) care. The current study aimed to investigate predictors of this outcome, focusing on patients' self‐reported psychological symptoms.

Methods and Materials

This is a secondary analysis of a randomized controlled trial that examined the efficacy of early palliative care integrated with standard oncology practice in patients with metastatic non‐small cell lung cancer (NSCLC). We analyzed associations between receipt of chemotherapy within 14 days of death and demographic, clinical, and quality‐of‐life variables in the 125 patients who received chemotherapy in the course of their illness and died during the 50‐month follow‐up.

Results

Twenty‐five patients (20%) received chemotherapy within the last 14 days of their life. Among demographic and clinical variables, only route of chemotherapy was significantly associated with receipt of chemotherapy within 14 days of death (oral 34.1% vs. intravenous (IV) 12.3%, p < 0.05). In the subsample of participants who received IV chemotherapy as their last regimen, greater anxiety and depression and lower quality of life in emotional, social, and existential domains were associated with greater likelihood of receiving chemotherapy at the EOL. These associations were not observed in patients who received oral chemotherapy as their last regimen.

Conclusion

Anxiety, depression, and worse psychological quality of life at early stage of treatment may be associated with the receipt of IV chemotherapy at the EOL. Further research is needed to examine how these factors might influence decision‐making about the discontinuation of chemotherapy at the EOL. Copyright © 2015 John Wiley & Sons, Ltd.
Monodisperse Emulsion Drop Microenvironments for Bacterial Biofilm Growth
Authors: Chang Connie B. , Wilking James N. , Kim Shin‐Hyun , Shum Ho Cheung , Weitz David A.
Published: May 2015

In this work, microfluidic technology is used to rapidly create hundreds of thousands of monodisperse double and triple emulsion drops that serve as 3D microenvironments for the containment and growth of bacterial biofilms. The size of these drops, with diameters from tens to hundreds of micrometers, makes them amenable to rapid manipulation and analysis. This is demonstrated by using microscopy to visualize cellular differentiation of Bacillus subtilis biofilm communities within each drop and the bacterial biofilm microstructure. Biofilm growth is explored upon specific interfaces in double and triple emulsions and upon negative and positive radii of curvature. Biofilm attachment of matrix and flagella mutants is studied as well as biofilms of Pseudomonas aeruginosa. This is the first demonstration of biofilms grown in microscale emulsion drops, which serve as both templates and containers for biofilm growth and attachment. These microenvironments have the potential to transform existing high‐throughput screening methods for bacterial biofilms.
Understanding constraints to the transformation rate of global energy infrastructure
Authors: Lane Joe L. , Smart Simon , Schmeda‐Lopez Diego , Hoegh‐Guldberg Ove , Garnett Andrew , Greig Chris , McFarland Eric
Published: May 2015

A massive transformation of the global energy supply system is required if deep reductions in atmospheric carbon dioxide emissions are to be achieved. A top–down review of historical data and energy forecasts provides a perspective on the magnitude of the challenge. Global engineering capability has expanded significantly over the last two decades, accommodating more than 100 GW/year increase in electricity generation infrastructure. However, business‐as‐usual demand forecasts to 2050 will require more than double the global rates of energy project execution. Transforming to a low‐carbon energy supply mix requires 30–70 GW/year of additional infrastructure, due to the increased reliance on intermittent renewables, and the earlier‐than‐expected replacement of existing coal power plants. Although all power systems share many similar subsystems that will need to be delivered regardless of the technology type, meeting the extra demands for engineering design, construction and/or supply chains may not be possible. The discussion focuses only on physical limitations of electricity generation, specifically around the timing and scale of retiring and/or replacing coal‐fired power generation capacity to meet the International Energy Agency's two‐degree scenario. We ignore the economics and politics of the transition scenarios and the transformation of the transportation and industrial sectors. What is clear is that the longer the delay in starting a significant transformation, the greater the challenge will become. Decision makers must understand the constraints to technology transitions to deliver effective policy. A broad international consensus is not required, instead reaching agreements and developing economically sustainable pathways to technology transitions in the United States, China, and India is more likely to be successful and the only means for significantly curbing global emissions. WIREs Energy Environ 2016, 5:33–48. doi: 10.1002/wene.177

This article is categorized under:

Energy Systems Economics > Systems and Infrastructure

Energy and Climate > Systems and Infrastructure

Energy Policy and Planning > Systems and Infrastructure

Energy Research & Innovation > Economics and Policy
Persistence of Methanosaeta populations in anaerobic digestion during process instability
Authors: Chen Si , He Qiang
Published: May 2015

Anaerobic digestion is a sustainable technology for the treatment of organic waste and production of biogas. Acetoclastic methanogenesis accounts for the majority of methane production in anaerobic digestion. Therefore, sustaining robust acetoclastic methanogens is important for stable process performance. Due to faster growth kinetics at high acetate concentrations, it has been considered that Methanosarcina would be more prevalent than Methanosaeta in unstable anaerobic digestion processes which frequently experience high acetate levels. Methanogen population dynamics were monitored in multiple continuous anaerobic digesters for 500 days. Results from quantitative polymerase chain reaction analysis show that Methanosaeta dominated over Methanosarcina in anaerobic digestion at high acetate levels up to 44 mM, suggesting the potential of Methanosaeta as a robust and efficient acetoclastic candidate for resilient anaerobic methane conversion. Further efforts are needed to identify mechanisms contributing to the unexpected competitiveness of these methanogens at high acetate levels observed in this study.
Pancreatic and Extrapancreatic Features in Autoimmune Pancreatitis
Authors: Kozoriz Michael G. , Chandler Tracy M. , Patel Roshni , Zwirewich Charles V. , Harris Alison C.
Published: May 2015

Autoimmune pancreatitis (AIP) accounts for approximately 5% of chronic pancreatitis cases and is an important consideration in the differential diagnosis of pancreatic pathologies. The underlying pathophysiology of AIP is thought to involve lymphocyte infiltration and associated sclerosis. Although AIP is a benign condition that is treatable with corticosteroids, it can have imaging and clinical findings indistinguishable from pancreatic cancer. As such, the radiologist plays an important management role in distinguishing AIP from more sinister conditions. In addition, there are several extrapancreatic imaging findings in the context of AIP that have been recently described. This pictorial review outlines both the pancreatic and extrapancreatic imaging features in AIP and the response to steroid therapy. Important imaging features that allow AIP to be differentiated from other pancreatic pathology, including adenocarcinoma, lymphoma, and acute pancreatitis will be discussed.
The Everyday Stress Resilience Hypothesis: A Reparatory Sensitivity and the Development of Coping and Resilience
Authors: Tronick Ed , DiCorcia Jennifer A.
Published: May 2015

Resilience is often associated with extreme trauma or overcoming extraordinary odds. This way of thinking about resilience leaves most of the ontogenetic picture a mystery. In the following review we put forth the Everyday Stress Resilience Hypothesis, in which resilience is analysed from a systems perspective and seen as a process of regulating everyday life stressors. Successful regulation accumulates into regulatory resilience, which emerges during early development from successful coping with the inherent stress in typical interactions. These quotidian stressful events lead to activation of behavioural and physiological systems. Stress that is effectively resolved in the short run and with reiteration over the long term increases children’s, as well as adults’, capacity to cope with more intense stressors. Infants, however, lack the regulatory capacities to take on this task by themselves. Therefore, through communicative and regulatory processes during infant–adult interactions, we demonstrate that the roots of regulatory resilience originate in infants’ relationships with their care givers and that maternal sensitivity can help or hinder the growth of resilience.
Amplitude and frequency modulation of the small scales in a jet
Authors: Fiscaletti D. , Ganapathisubramani B. , Elsinga G. E.
Published: May 2015

The present study is an experimental investigation of the relationship between the large- and small-scale motions in the far field of an air jet at high Reynolds number. In the first part of our investigation, the analysis is based on time series of hot-wire anemometry (HWA), which are converted into space series after applying the Taylor hypothesis. By using a spectral filter, two signals are constructed, one representative of the large-scale motions ($2{\it\lambda}_{T}-L$, where${\it\lambda}_{T}$is the Taylor length scale, and$L$is the integral length scale) and the other representative of the small-scale motions ($1.5{-}5{\it\eta}$, where${\it\eta}$is the Kolmogorov length scale). The small-scale signal is found to be modulated both in amplitude and in frequency by the energy-containing scales in an analogous way, both at the centreline and around the centreline. In particular, for positive fluctuations of the large-scale signal, the small-scale signal is locally stronger in amplitude (amplitude modulation), and it locally exhibits a higher number of local maxima and minima (frequency modulation). The extent of this modulation is quantified based on the strength of the large-scale fluctuations. The response of the small-scale motions to amplitude modulation can be considered instantaneous, being on the order of one Kolmogorov time scale. In the second part of our investigation we use long-range${\it\mu}$PIV to study the behaviour of the small-scale motions in relation to their position in either high-speed or low-speed regions of the flow. The spatially resolved velocity vector fields allow us to quantify amplitude modulation directly in physical space. From this direct estimation in physical space, amplitude modulation is only 25 % of the value measured from HWA. The remaining 75 % comes from the fixed spectral band filter used to obtain the large- and small-scale signals, which does not consider the local convection velocity. A very similar overestimation of amplitude modulation when quantified in the time-frame is also obtained analytically. Furthermore, the size of the structures of intense vorticity does not change significantly in relation to the large-scale velocity fluctuation, meaning that there is no significant spatial frequency modulation. The remaining amplitude modulation in space can be explained as a statistical coupling between the strength of the structures of vorticity and their preferential location inside large-scale high-velocity regions. Finally, the implications that the present findings have on amplitude and frequency modulation in turbulent boundary layers (TBLs) are discussed.
Adding Another Level Individual Responses to Globalization and Government Welfare Policies
Authors: Schaffer Lena , Spilker Gabriele
Published: May 2015

Literature on the compensation hypothesis overwhelmingly concentrates on either the macro or micro level of the relationship between globalization and welfare spending. This paper explicitly addresses this shortcoming by using individual citizens and country-specific characteristics in a hierarchical model framework. We start by examining individual’s context-conditional reactions to actual economic globalization and welfare generosity; after which, we make the effect of actual economic globalization (welfare generosity) conditional on whether the individual is a globalization winner or loser. In contrast to theoretical expectations, our results indicate that actual economic globalization does not affect people’s perception in the manner expected by the compensation hypothesis. However, individuals display more positive attitudes toward globalization if welfare state generosity is proxied using government spending on active labor market programs.
The Guardianship Dilemma: Regime Securitythroughandfromthe Armed Forces—ERRATUM
Authors: MCMAHON R. BLAKE , SLANTCHEV BRANISLAV L.
Published: May 2015

Owing to an editorial oversight, the citation and reference for Piplani and Talmadge (2015) was deleted twice on page 307 of the May 2015 issue ofAmerican Political Science Review. The citations should read as follows:

In this context, it is useful to consider the empirical results of two studies that find that the probability of coups is lower if the country is involved in a war (Piplani and Talmadge, 2015) and even in a crisis (Arbatli and Arbatli, 2014). The explanatory mechanisms these studies offer are different (although not necessarily incompatible): Piplani and Talmadge (2015) argue that when the military is engaged in a war there are fewer opportunities for a coup and more uncertainty about who will join it, whereas Arbatli and Arbatli (2014) argue that crises allow rulers to commit credibly to transfers to the military and to generate rally-around-the-flag effects.

Also, owing to a printer's error on page 305, Qaddafi is misspelled as Qaddaf.

We regret these errors.
Female disability disadvantage: a global perspective on sex differences in physical function and disability
Authors: WHEATON FELICIA V. , CRIMMINS EILEEN M.
Published: May 2015

The objectives were to determine whether women always fare more poorly in terms of physical function and disability across countries that vary widely in terms of their level of development, epidemiologic context and level of gender equality. Sex differences in self-reported and objective measures of disability and physical function were compared among older adults aged 55–85 in the United States of America, Taiwan, Korea, Mexico, China, Indonesia and among the Tsimane of Bolivia using population-based studies collected between 2001 and 2011. Data were analysed using logistic and ordinary least-squares regression. Confidence intervals were examined to see whether the effect of being female differed significantly between countries. In all countries, women had consistently worse physical functioning (both self-reported and objectively measured). Women also tended to report more difficulty with activities of daily living (ADL), although differences were not always significant. In general, sex differences across measures were less pronounced in China. In Korea, women had significantly lower grip strength, but sex differences in ADL difficulty were non-significant or even reversed. Education and marital status helped explain sex differences. Overall, there was striking similarity in the magnitude and direction of sex differences across countries despite considerable differences in context, although modest variations in the effect of sex were observed.
Topological control of the Caulobacter cell cycle circuitry by a polarized single-domain PAS protein
Authors: Sanselicio Stefano , Bergé Matthieu , Théraulaz Laurence , Radhakrishnan Sunish Kumar , Viollier Patrick H.
Published: May 2015

Despite the myriad of different sensory domains encoded in bacteria, only a few types are known to control the cell cycle. Here we use a forward genetic screen for Caulobacter crescentus motility mutants to identify a conserved single-domain PAS (Per-Arnt-Sim) protein (MopJ) with pleiotropic regulatory functions. MopJ promotes re-accumulation of the master cell cycle regulator CtrA after its proteolytic destruction is triggered by the DivJ kinase at the G1-S transition. MopJ and CtrA syntheses are coordinately induced in S-phase, followed by the sequestration of MopJ to cell poles in Caulobacter. Polarization requires Caulobacter DivJ and the PopZ polar organizer. MopJ interacts with DivJ and influences the localization and activity of downstream cell cycle effectors. Because MopJ abundance is upregulated in stationary phase and by the alarmone (p)ppGpp, conserved systemic signals acting on the cell cycle and growth phase control are genetically integrated through this conserved single PAS-domain protein.
Direct observation of finite size effects in chains of antiferromagnetically coupled spins
Authors: Guidi T. , Gillon B. , Mason S. A. , Garlatti E. , Carretta S. , Santini P. , Stunault A. , Caciuffo R. , van Slageren J. , Klemke B. , Cousson A. , Timco G. A. , Winpenny R. E. P.
Published: May 2015

Finite spin chains made of few magnetic ions are the ultimate-size structures that can be engineered to perform spin manipulations for quantum information devices. Their spin structure is expected to show finite size effects and its knowledge is of great importance both for fundamental physics and applications. Until now a direct and quantitative measurement of the spatial distribution of the magnetization of such small structures has not been achieved even with the most advanced microscopic techniques. Here we present measurements of the spin density distribution of a finite chain of eight spin-3/2 ions using polarized neutron diffraction. The data reveal edge effects that are a consequence of the finite size and of the parity of the chain and indicate a noncollinear spin arrangement. This is in contrast with the uniform spin distribution observed in the parent closed chain and the collinear arrangement in odd-open chains.
Synthesis of new metastable nanoalloys of immiscible metals with a pulse laser technique
Authors: Swiatkowska-Warkocka Zaneta , Pyatenko Alexander , Krok Franciszek , Jany Benedykt R. , Marszalek Marta
Published: May 2015

The generation of nanoalloys of immiscible metals is still a challenge using conventional methods. However, because these materials are currently attracting much attention, alternative methods are needed. In this article, we demonstrate a simple but powerful strategy for the generation of a new metastable alloy of immiscible metals. Au1−xNix 3D structures with 56 at% of nickel in gold were successfully manufactured by the pulsed laser irradiation of colloidal nanoparticles. This technology can be used for preparing different metastable alloys of immiscible metals. We hypothesise that this technique leads to the formation of alloy particles through the agglomerations of nanoparticles, very fast heating and fast cooling/solidification. Thus, we expect that our approach will be applicable to a wide range of inorganic solids, yielding even new metastable solids that fail to be stable in the bulk systems and therefore do not exist in Nature.
The T cell receptor resides in ordered plasma membrane nanodomains that aggregate upon patching of the receptor
Authors: Dinic Jelena , Riehl Astrid , Adler Jeremy , Parmryd Ingela
Published: May 2015

Two related models for T cell signalling initiation suggest either that T cell receptor (TCR) engagement leads to its recruitment to ordered membrane domains, often referred to as lipid rafts, where signalling molecules are enriched or that ordered TCR-containing membrane nanodomains coalesce upon TCR engagement. That ordered domains form upon TCR engagement, as they do upon lipid raft marker patching, has not been considered. The target of this study was to differentiate between those three options. Plasma membrane order was followed in live T cells at 37 °C using laurdan to report on lipid packing. Patching of the TCR that elicits a signalling response resulted in aggregation, not formation, of ordered plasma membrane domains in both Jurkat and primary T cells. The TCR colocalised with actin filaments at the plasma membrane in unstimulated Jurkat T cells, consistent with it being localised to ordered membrane domains. The colocalisation was most prominent in cells in G1 phase when the cells are ready to commit to proliferation. At other cell cycle phases the TCR was mainly found at perinuclear membranes. Our study suggests that the TCR resides in ordered plasma membrane domains that are linked to actin filaments and aggregate upon TCR engagement.
Enhanced piezoelectric properties of vertically aligned single-crystalline NKN nano-rod arrays
Authors: Kang Min-Gyu , Oh Seung-Min , Jung Woo-Suk , Gyu Moon Hi , Baek Seung-Hyub , Nahm Sahn , Yoon Seok-Jin , Kang Chong-Yun
Published: May 2015

Piezoelectric materials capable of converting between mechanical and electrical energy have a great range of potential applications in micro- and nano-scale smart devices; however, their performance tends to be greatly degraded when reduced to a thin film due to the large clamping force by the substrate and surrounding materials. Herein, we report an effective method for synthesizing isolated piezoelectric nano-materials as means to relax the clamping force and recover original piezoelectric properties of the materials. Using this, environmentally friendly single-crystalline NaxK1-xNbO3 (NKN) piezoelectric nano-rod arrays were successfully synthesized by conventional pulsed-laser deposition and demonstrated to have a remarkably enhanced piezoelectric performance. The shape of the nano-structure was also found to be easily manipulated by varying the energy conditions of the physical vapor. We anticipate that this work will provide a way to produce piezoelectric micro- and nano-devices suitable for practical application and in doing so, open a new path for the development of complex metal-oxide nano-structures.
The chemical biology of sirtuins
Authors: Chen Bing , Zang Wenwen , Wang Juan , Huang Yajun , He Yanhua , Yan Lingling , Liu Jiajia , Zheng Weiping
Published: May 2015

This article reviews the tremendous accomplishments achieved during the past few years in the field of chemical biology for the physiologically and therapeutically important sirtuin family of Nε-acyl-lysine deacylase enzymes.
The emergence of sulfoxides as efficient ligands in transition metal catalysis
Authors: Sipos Gellért , Drinkel Emma E. , Dorta Reto
Published: May 2015

This review describes the use of sulfoxides as ancillary ligands in transition metal catalysis.
Being two is better than one—catalytic reductions with dendrimer encapsulated copper- and copper–cobalt-subnanoparticles
Authors: Ficker Mario , Petersen Johannes F. , Gschneidtner Tina , Rasmussen Ann-Louise , Purdy Trevor , Hansen Jon S. , Hansen Thomas H. , Husted Søren , Moth Poulsen Kasper , Olsson Eva , Christensen Jørn B.
Published: May 2015

Copper and copper–cobalt subnanoparticles have been synthesized using 4-carbomethoxypyrrolidone terminated PAMAM-dendrimers as templates.
Biodegradable hollow silica nanospheres containing gold nanoparticle arrays
Authors: Cassano Domenico , Rota Martir Diego , Signore Giovanni , Piazza Vincenzo , Voliani Valerio
Published: May 2015

A protocol to synthesize novel inorganic nanosystems that could avoid the issue of persistence/accumulation in organisms is presented.
Graphene-based catalysis for biomass conversion
Authors: Zhu Shanhui , Wang Jianguo , Fan Weibin
Published: May 2015

This perspective summarizes the advances and challenges of graphene-based materials in the conversion of biomass into chemicals and biofuels.
The non-aqueous fluorolytic sol–gel synthesis of nanoscaled metal fluorides
Authors: Kemnitz Erhard , Noack Johannes
Published: May 2015

Nanoscopic metal fluorides with new applications.
Characterization of an alkaline earth metal-doped solid superacid and its activity for the esterification of oleic acid with methanol
Authors: Huang Chien-Chang , Yang Chieh-Ju , Gao Pei-Jyuan , Wang Nai-Ci , Chen Ching-Lung , Chang Jo-Shu
Published: May 2015

A schematic diagram for explaining the deactivation of the active sites located in the high diffusion barrier zone is shown.
Biodegradable betaine-based aprotic task-specific ionic liquids and their application in efficient SO2 absorption
Authors: Yang Benqun , Zhang Qinghua , Fei Yuqing , Zhou Feng , Wang Peixue , Deng Youquan
Published: May 2015

Biodegradable betaine-based aprotic task-specific ionic liquids and their application in efficient SO2 absorption.
Multiplexing determination of lung cancer biomarkers using electrochemical and surface-enhanced Raman spectroscopic techniques
Authors: Lu Wenbo , Wang Ying , Cao Xiaowei , Li Li , Dong Jian , Qian Weiping
Published: May 2015

A reliable immunosensor for simultaneous detection of carcinoembryonic antigen and cytokeratin-19 by complementary advantages of the electrochemical and SERS technologies.
A practical deca-gram scale ring expansion of (R)-(−)-carvone to (R)-(+)-3-methyl-6-isopropenyl-cyclohept-3-enone-1
Authors: Alves Leandro de C. , Desiderá André L. , de Oliveira Kleber T. , Newton Sean , Ley Steven V. , Brocksom Timothy J.
Published: May 2015

A route to enantiopure (R)-(+)-3-methyl-6-isopropenyl-cyclohept-3-enone-1, an intermediate for terpenoids, has been developed and includes a highly chemo- and regioselective Tiffeneau–Demjanov reaction.
Recent developments and applications of the Cadiot–Chodkiewicz reaction
Authors: Sindhu K. S. , Thankachan Amrutha P. , Sajitha P. S. , Anilkumar Gopinathan
Published: May 2015

The classical heterocoupling of a 1-haloalkyne with a terminal alkyne catalyzed by copper salts in the presence of a base for the synthesis of unsymmetrical diynes is termed the Cadiot–Chodkiewicz coupling reaction.
Bipyridinium radical cation dimerization-driven polymeric pleated foldamers and a homoduplex that undergo ion-tuned interconversion
Authors: Zhang Yun-Chang , Zhang Dan-Wei , Wang Hui , Zhou Yaming , Li Zhan-Ting
Published: May 2015

Radical cation dimerization induces bipyridinium-derived polymers to form pleated secondary structures and a homoduplex which can be tuned by ammonium to interconvert.
Aqueous radical addition-coupling polymerization using a nitroso benzene/cyclodextrin complex for the synthesis of a hydrophilic periodic polymer
Authors: Tao Fangqi , Wang Qi
Published: May 2015

Hydrophilic periodic polymer possessing [ABxAC]n repeating sequence was synthesized by aqueous radical addition-coupling polymerization using water-soluble inclusion complex of nitrosobenzene and Me2-β-cyclodextrin.
Glycerol steam reforming over La–Ce–Co mixed oxide-derived cobalt catalysts
Authors: Surendar M. , Sagar T. V. , Babu B. Hari , Lingaiah N. , Rao K. S. Rama , Prasad P. S. Sai
Published: May 2015

Cobalt nano particles derived from the La–Ce–Co mixed oxide, after reduction, are highly active for glycerol steam reforming to produce hydrogen.
Thermodynamic investigation of the interaction between the [(η6-p-cymene)Ru(benzaldehyde-N4-phenylthiosemicarbazone)Cl]Cl anticancer drug and ctDNA: multispectroscopic and electrochemical studies
Authors: Huang Shan , Zhu Fawei , Xiao Qi , Liang Yu , Zhou Quan , Su Wei
Published: May 2015

The interaction between the [(η6-p-cymene)Ru(benzaldehyde-N4-phenylthiosemicarbazone)Cl]Cl anticancer drug and ctDNA was systematically investigated by multispectroscopic and electrochemical studies.
Synthesis and properties of visible light responsive g-C3N4/Bi2O2CO3 layered heterojunction nanocomposites
Authors: Zhang Qian , Wang Haoying , Hu Shaozheng , Lu Guang , Bai Jin , Kang Xiaoxue , Liu Dan , Gui Jianzhou
Published: May 2015

A g-C3N4/Bi2O2CO3 layered heterojunction nanocomposite exhibits more effective separation of photogenerated electron–hole pairs and a stable chemical structure, thus showing higher photocatalytic activity and stability.
Application of ordered mesoporous silica nanocontainers in an anticorrosive epoxy coating on a magnesium alloy surface
Authors: Qiao Yingjie , Li Wenpeng , Wang Guixiang , Zhang Xiaohong , Cao Nana
Published: May 2015

Epoxy coatings containing inhibitor loaded silica nanocontainers were applied to Mg alloy. When damage was caused in coatings during immersion time, the coatings displayed self-healing property with the release of inhibitor from nanocontainers.
Polymeric Janus nanoparticles templated by block copolymer thin films
Authors: Poggi Elio , Bourgeois Jean-Pierre , Ernould Bruno , Gohy Jean-François
Published: May 2015

We report a novel approach to synthesize well-defined polymeric Janus nanoparticles by combining the self-assembly of block copolymers in thin films and surface modification by polymer grafting.
Cellulosic poly(ionic liquid)s: synthesis, characterization and application in the cycloaddition of CO2 to epoxides
Authors: Chen Qin , Peng Chang , Xie Haibo , Zhao Zongbao kent , Bao Ming
Published: May 2015

Cellulosic poly(ionic liquid)s were prepared via nucleophilic substitution of chlorinated cellulose by 1-methyl-imidazole and their structure and thermal properties have been characterized, which were ready for the preparation of novel cellulosic materials.
Development of a topical adapalene-solid lipid nanoparticle loaded gel with enhanced efficacy and improved skin tolerability
Authors: Harde Harshad , Agrawal Ashish Kumar , Katariya Mahesh , Kale Dnyaneshwar , Jain Sanyog
Published: May 2015

The present investigation substantiates the efficacy of adapalene loaded solid lipid nanoparticles (Ada-SLNs) in ameliorating the skin irritation potential of adapalene owing to its altered skin distribution.
Size-selective incorporation of donor–acceptor linked dyad cations into zeolite Y and long-lived charge separation
Authors: Fukuzumi Shunichi , Itoh Akinori , Ohkubo Kei , Suenobu Tomoyoshi
Published: May 2015

3-Mesityl-1-methylquinolinium ion is incorporated into a supercage of zeolite Y, exhibiting long-lived charge separation upon photoexcitation.
A remarkable sensitivity enhancement in a gold nanoparticle-based lateral flow immunoassay for the detection of Escherichia coli O157:H7
Authors: Cui Xi , Huang Youju , Wang Jingyun , Zhang Lei , Rong Yun , Lai Weihua , Chen Tao
Published: May 2015

The size and uniformity of AuNPs were optimized to maximally amplify both visual inspection signals and quantitative data of LFA.
A novel colorimetric triple-helix molecular switch aptasensor based on peroxidase-like activity of gold nanoparticles for ultrasensitive detection of lead(ii)
Authors: Taghdisi Seyed Mohammad , Danesh Noor Mohammad , Lavaee Parirokh , Emrani Ahmad Sarreshtehdar , Ramezani Mohammad , Abnous Khalil
Published: May 2015

Lead (Pb) is a serious environmental contaminant and one of the most toxic heavy metals.
Highly luminescent, off-stoichiometric CuxInyS2/ZnS quantum dots for near-infrared fluorescence bio-imaging
Authors: Choi Hyung Seok , Kim Youngsun , Park Jae Chul , Oh Mi Hwa , Jeon Duk Young , Nam Yoon Sung
Published: May 2015

We synthesized highly luminescent, NIR-emitting copper–indium–sulfur/zinc sulfide (CIS/ZnS) core–shell QDs with a high photoluminescence quantum yield (about 60%) using a heating up method.
Microdialysis SPR: diffusion-gated sensing in blood
Authors: Breault-Turcot Julien , Masson Jean-Francois
Published: May 2015

Chemical measurements are rarely performed in crude blood due to the poor performance of sensors and devices exposed to biofluids.
Effect of hydrogenation on the microwave absorption properties of BaTiO3 nanoparticles
Authors: Tian Lihong , Yan Xiaodong , Xu JiLian , Wallenmeyer Petra , Murowchick James , Liu Lei , Chen Xiaobo
Published: May 2015

Hydrogenation largely improves the microwave absorbing efficiency of BaTiO3 nanoparticles.
Advanced solid-state asymmetric supercapacitors based on 3D graphene/MnO2 and graphene/polypyrrole hybrid architectures
Authors: Zhang Zheye , Chi Kai , Xiao Fei , Wang Shuai
Published: May 2015

Two types of 3D architectured electrodes, i.e., graphene wrapped nickel foam Ni/GF/MnO2 and Ni/GF/polypyrrole (PPy), were successfully fabricated for high performance flexible solid-state asymmetric supercapacitors.
Vacuum-evaporable spin-crossover complexes: physicochemical properties in the crystalline bulk and in thin films deposited from the gas phase
Authors: Naggert H. , Rudnik J. , Kipgen L. , Bernien M. , Nickel F. , Arruda L. M. , Kuch W. , Näther C. , Tuczek F.
Published: May 2015

Vacuum-evaporable Fe(ii) complexes exhibit greatly different spin-crossover behaviour in thin films deposited from the gas phase and the crystalline bulk.
Upconverting nanocomposites dispersed in urea-containing acrylics
Authors: Inglefield D. L. , Merritt T. R. , Magill B. A. , Long T. E. , Khodaparast G. A.
Published: May 2015

Lanthanide-doped upconverting nanoparticles (UCNPs) have the ability to convert low energy photons into high energy photons, making this material appealing for a variety of scientific pursuits, from solar energy conversion to bioimaging.
β-Pro7Ang III is a novel highly selective angiotensin II type 2 receptor (AT2R) agonist, which acts as a vasodepressor agent via the AT2R in conscious spontaneously hypertensive rats
Authors: Del Borgo Mark , Wang Yan , Bosnyak Sanja , Khan Morimer , Walters Pia , Spizzo Iresha , Perlmutter Patrick , Hilliard Lucinda , Denton Kate , Aguilar Marie-Isabel , Widdop Robert E. , Jones Emma S.
Published: May 2015

We have previously shown that individual β-amino acid substitution in angiotensin (Ang) II reduced Ang II type 1 receptor (AT1R) but not Ang II type 2 receptor (AT2R)-binding and that the heptapeptide Ang III exhibited greater AT2R:AT1R selectivity than Ang II. Therefore, we hypothesized that β-amino-acid-substituted Ang III peptide analogues would yield highly selective AT2R ligands, which we have tested in binding and functional vascular assays. In competition binding experiments using either AT1R- or AT2R-transfected human embryonic kidney (HEK)-293 cells, novel β-substituted Ang III analogues lacked appreciable AT1R affinity, whereas most compounds could fully displace 125I-Sar1Ile8 Ang II from AT2R. The rank order of affinity at AT2R was CGP42112 > Ang III > β-Pro7 Ang III=Ang II > β-Tyr4 Ang III ≥ PD123319 >> β-Phe8 Ang III >> β Arg2 Ang III=β-Val3 Ang III >> β-Ile5 Ang III. The novel analogue β-Pro7 Ang III was the most selective AT2R ligand tested, which was >20 000-fold more selective for AT2R than AT1R. IC50 values at AT2R from binding studies correlated with maximum vasorelaxation in mouse aortic rings. Given that β-Pro7 Ang III was an AT2R agonist, we compared β-Pro7 Ang III and native Ang III for their ability to reduce blood pressure in separate groups of conscious spontaneously hypertensive rats. Whereas Ang III alone increased mean arterial pressure (MAP), β-Pro7 Ang III had no effect. During low-level AT1R blockade, both Ang III and β-Pro7 Ang III, but not Ang II, lowered MAP (by ∼30 mmHg) at equimolar infusions (150 pmol/kg/min for 4 h) and these depressor effects were abolished by the co-administration of the AT2R antagonist PD123319. Thus, β-Pro7 Ang III has remarkable AT2R selectivity determined in binding and functional studies and will be a valuable research tool for insight into AT2R function and for future drug development.
On the intrinsic optical bistability of a single Kerr nonlinear dielectric layer
Authors: Ibrahim Abdel-Baset M. A.
Published: May 2015

In this study, we investigate the optical bistability and multistability in a pure single Kerr nonlinear layer of dielectric material using the Maxwell-Duffing approach. We employ the Duffing anharmonic oscillator as an alternative constitutive relation to express the electric field as a nonlinear function of the induced polarization. Utilizing both the electromagnetic wave equation and the Duffing constitutive relation, we obtain a nonlinear polarization equation propagates through the nonlinear layer under the slowly varying envelope approximation. With the application of boundary conditions at both interfaces, expressions for the incident, reflected, and transmitted intensities of the light wave are obtained as nonlinear functions of the polarization and other controlling parameters. For realistic input parameters, our numerical results demonstrated the existence of an intrinsic optical bistability (IOB) in a pure single dielectric layer. Furthermore, the threshold value of the observed IOB depends essentially on the value Eth, i.e., the minimum value required to invoke the third-order nonlinearity inside the material. For operating frequency near the sharp resonance region, Eth was found to be ≈105 V/cm; this is equivalent to a threshold value of the optical intensity ≈1010 W/cm2. With the developments in THz sources, it is nowadays possible to observe this IOB experimentally by tuning the operating frequency near the sharp resonance region of the material. Steps to get the threshold value of Eth are also advised.
In vitro fibrillization of Alzheimer’s amyloid-β peptide (1-42)
Authors: Tiiman Ann , Krishtal Jekaterina , Palumaa Peep , Tõugu Vello
Published: May 2015

The amyloid deposition in the form of extracellular fibrillar aggregates of amyloid-β (Aβ) peptide is a critical pathological event in Alzheimer’s disease. Here, we report a systematic investigation of the effects of environmental factors on the kinetics of Aβ fibrillization in vitro. The effects of Aβ42 peptide concentration, temperature, pH, added solvents and the ratio of Aβ40 and Aβ42 on the peptide fibrillization under agitated conditions was studied. The analysis show that the rate of fibril growth by monomer addition is not limited by diffusion but by rearrangement in the monomer structure, which is enhanced by low concentrations of fluorinated alcohols and characterized by the activation energy of 12 kcal/mol. Fibrillization rate decreases at pH values below 7.0 where simultaneous protonation of His 13 and 14 inhibits fibril formation. The lag period for Aβ42 was only twofold shorter and the fibril growth rate twofold faster than those of Aβ40. Lag period was shortened and the fibrillization rate was increased only at 90% content of Aβ42.