bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensing and transducing forces in plants with MSL10 and DEK1 mechanosensors
Authors: Guerringue Yannick , Thomine Sébastien , Frachisse Jean‐Marie
Published: May 2018

Mechanosensitive (MS) channels behave as microprobes that transduce mechanical tension into electric and ion signals. The plasma membrane anion‐permeable channel AtMSL10 belongs to the first family of MS channels (MscS‐LIKE) that has been characterized in Arabidopsis thaliana. In the same membrane, a rapidly activated calcium MS channel activity (RMA) associated with the presence of the DEFECTIVE KERNEL1 (AtDEK1) protein has been recently described. In this Review, based on the comparison of the specific properties of AtMSL10 and RMA, we put forward hypotheses on the mechanism of activation of these two channels, their respective roles in signalling and also raise the question of the molecular identity of RMA. Finally, we propose functions for these two channels within the context of plant mechanotransduction.
Comparison of the progressive resolution optimizer and photon optimizer in VMAT optimization for stereotactic treatments
Authors: Liu Han , Sintay Benjamin , Pearman Keith , Shang Qingyang , Hayes Lane , Maurer Jacqueline , Vanderstraeten Caroline , Wiant David
Published: May 2018

The photon optimization (PO) algorithm was recently released by Varian Medical Systems to improve volumetric modulated arc therapy (VMAT) optimization within Eclipse (Version 13.5). The purpose of this study is to compare the PO algorithm with its predecessor, progressive resolution optimizer (PRO) for lung SBRT and brain SRS treatments. A total of 30 patients were selected retrospectively. Previously, all the plans were generated with the PRO algorithm within Eclipse Version 13.6. In the new version of PO algorithm (Version 15), dynamic conformal arcs (DCA) were first conformed to the target, then VMAT inverse planning was performed to achieve the desired dose distributions. PTV coverages were forced to be identical for the same patient for a fair comparison. SBRT plan quality was assessed based on selected dose–volume parameters, including the conformity index, V20 for lung, V30 Gy for chest wall, and D0.035 cc for other critical organs. SRS plan quality was evaluated based on the conformity index and normal tissue volumes encompassed by the 12 and 6 Gy isodose lines (V12 and V6). The modulation complexity score (MCS) was used to compare plan complexity of two algorithms. No statistically significant differences between the PRO and PO algorithms were found for any of the dosimetric parameters studied, which indicates both algorithms produce comparable plan quality. Significant improvements in the gamma passing rate (increased from 97.0% to 99.2% for SBRT and 96.1% to 98.4% for SRS), MCS (average increase of 0.15 for SBRT and 0.10 for SRS), and delivery efficiency (MU reduction of 29.8% for SBRT and 28.3% for SRS) were found for the PO algorithm. MCS showed a strong correlation with the gamma passing rate, and an inverse correlation with total MUs used. The PO algorithm offers comparable plan quality to the PRO, while minimizing MLC complexity, thereby improving the delivery efficiency and accuracy.
High‐Performance Supercapacitors Based on a Zwitterionic Network of Covalently Functionalized Graphene with Iron Tetraaminophthalocyanine
Authors: Bakandritsos Aristides , Chronopoulos Demetrios D. , Jakubec Petr , Pykal Martin , Čépe Klára , Steriotis Theodore , Kalytchuk Sergii , Petr Martin , Zbořil Radek , Otyepka Michal
Published: May 2018

Graphene derivatives are promising candidates as electrode materials in supercapacitor cells, therefore, functionalization strategies are pursued to improve their performance. A scalable approach is reported for preparing a covalently and homogenously functionalized graphene with iron tetraaminophthalocyanine (FePc‐NH2) with a high degree of functionalization. This is achieved by exploiting fluorographene's reactivity with the diethyl bromomalonate, producing graphene‐dicarboxylic acid after hydrolysis, which is conjugated with FePc‐NH2. The material exhibits an ultrahigh gravimetric specific capacitance of 960 F g−1 at 1 A g−1 and zero losses upon charging–discharging cycling. The energy density of 59 Wh kg−1 is eminent among supercapacitors operating in aqueous electrolytes with graphene‐based electrode materials. This is attributed to the structural and functional synergy of the covalently bound components, giving rise to a zwitterionic surface with extensive π–π stacking, but not graphene restacking, all being very beneficial for charge and ionic transport. The safety of the proposed system, owing to the benign Na2SO4 aqueous electrolyte, the high capacitance, energy density, and potential of preparing the electrode material on a large‐scale and at low cost make the reported strategy very attractive for development of supercapacitors based on the covalent attachment of suitable molecules onto graphene toward high‐synergy hybrids.
Voltage‐Gated Closed‐Loop Control of Small‐Molecule Release from Alumina‐Coated Nanoporous Gold Thin Film Electrodes
Authors: Li Zidong , Polat Ozge , Seker Erkin
Published: May 2018

Precise timing and dosing of potent small‐molecule drugs carries significant potential for effective pharmaceutical management of disorders that exhibit time‐varying therapeutic windows such as epilepsy. This study demonstrates the use of alumina‐coated nanoporous gold (np‐Au) thin film electrodes for iontophoretic release of fluorescein as a small‐molecule drug surrogate with picogram dosing and a few seconds temporal resolution. A custom microfluidic platform is engineered to trigger molecular release from an integrated np‐Au chip and monitor the resulting time‐varying fluorescein concentration. Following a systematic study of the influence of applied voltage on loading capacity and release kinetics, a LabVIEW‐based closed‐loop control interface is employed to demonstrate voltage‐gated fluorescein release with preprogrammed arbitrary concentrations waveforms.
MgSiAs: An Unexplored System with Promising Nonlinear Optical Properties
Authors: Woo Katherine E. , Wang Jian , Wu Kui , Lee Kathleen , Dolyniuk Juli‐Anna , Pan Shilie , Kovnir Kirill
Published: May 2018

Two new non‐centrosymmetric ternary compounds, MgSiAs2 and Mg3Si6As8, are discovered via metal flux and solid‐state synthetic methods. MgSiAs2 belongs to the well‐known II‐IV‐V2 family, which is extensively studied experimentally and computationally for their optical properties. MgSiAs2 is computationally predicted but not experimentally known prior to this work. Mg3Si6As8 crystallizes in a new non‐centrosymmetric cubic chiral structure type with the Pearson symbol cP68. The syntheses, crystal structure, thermal and chemical stabilities, electronic structures, and optical properties of these two new compounds are investigated in this work. Optical absorption measurements and electronic structure calculations reveal the two compounds to be direct or pseudo‐direct bandgap semiconductors (1.8–2 eV). The crystal structures of both compounds are non‐centrosymmetric, though Mg3Si6As8 belongs to the 432 chiral crystal class, which is optically active but does not exhibit second harmonic generation (SHG) behavior. The SHG response of MgSiAs2 is 60% of that for AgGaS2, but MgSiAs2 exhibits a higher laser damage threshold than AgGaS2 at 33.2 MW cm−2.
Microengineered Bioartificial Liver Chip for Drug Toxicity Screening
Authors: Delalat Bahman , Cozzi Chiara , Rasi Ghaemi Soraya , Polito Giovanni , Kriel Frederik H. , Michl Thomas Danny , Harding Frances J. , Priest Craig , Barillaro Giuseppe , Voelcker Nicolas H.
Published: May 2018

Microfluidic 3D cell culture is a promising technology for the screening of drug toxicity profiles. In this study, a bioartificial liver consisting of a surface‐engineered microfluidic silicon chip with microtrenches mimicking hepatic sinusoids is shown to extend 3D primary hepatocyte culture and improve in vitro drug screening for hepatotoxicity, with respect to the state‐of‐the‐art literature on this subject. Primary hepatocytes hosted in the 3D heparin‐coated microtrenches (the bioartificial liver) secrete high levels of albumin and urea over 4 weeks. The cytotoxicity of common drugs, namely, acetaminophen, chlorpromazine, and tacrine, was assessed on primary hepatocytes both at day 1 and day 7. The results suggest that mimicking hepatic sinusoids using a microtrench format allows the maintenance of difficult‐to‐culture primary hepatocytes to be extended to 4 weeks and provides an alternative model to animal studies for the screening of the cytotoxicity of new drugs.
Nickel@Nickel Oxide Core–Shell Electrode with Significantly Boosted Reactivity for Ultrahigh‐Energy and Stable Aqueous Ni–Zn Battery
Authors: Wang Rui , Han Yi , Wang Zifan , Jiang Jiuxing , Tong Yexiang , Lu Xihong
Published: May 2018

The main bottlenecks of aqueous rechargeable Ni–Zn batteries are their relatively low energy density and poor cycling stability, mainly arising from the low capacity and inferior reversibility of the current Ni‐based cathodes. Additionally, the complicated and difficult‐to‐scale preparation procedures of these cathodes are not promising for large‐scale energy storage. Here, a facile and cost‐effective ultrasonic‐assisted strategy is developed to efficiently activate commercial Ni foam as a robust cathode for a high‐energy and stable aqueous rechargeable Ni–Zn battery. 3D Ni@NiO core–shell electrode with remarkably boosted reactivity and an area of 300 cm2 is readily obtained by this ultrasonic‐assisted activation method (denoted as SANF). Benefiting from the in situ formation of electrochemically active NiO and porous 3D structure with a large surface area, the as‐fabricated SANF//Zn battery presents ultrahigh capacity (0.422 mA h cm−2) and excellent cycling durability (92.5% after 1800 cycles). Moreover, this aqueous rechargeable SANF//Zn battery achieves an impressive energy density of 15.1 mW h cm−3 (0.754 mW h cm−2) and a peak power density of 1392 mW cm−3, outperforming most reported aqueous rechargeable energy‐storage devices. These findings may provide valuable insights into designing large‐scale and high‐performance 3D electrodes for aqueous rechargeable batteries.
Composition‐Graded Cesium Lead Halide Perovskite Nanowires with Tunable Dual‐Color Lasing Performance
Authors: Huang Ling , Gao Qinggang , Sun Ling‐Dong , Dong Hao , Shi Shuo , Cai Tong , Liao Qing , Yan Chun‐Hua
Published: May 2018

Cesium lead halide (CsPbX3) perovskite has emerged as a promising low‐threshold multicolor laser material; however, realizing wavelength‐tunable lasing output from a single CsPbX3 nanostructure is still constrained by integrating different composition. Here, the direct synthesis of composition‐graded CsPbBrxI3−x nanowires (NWs) is reported through vapor‐phase epitaxial growth on mica. The graded composition along the NW, with an increased Br/I from the center to the ends, comes from desynchronized deposition of cesium lead halides and temperature‐controlled anion‐exchange reaction. The graded composition results in varied bandgaps along the NW, which induce a blueshifted emission from the center to the ends. As an efficient gain media, the nanowire exerts position‐dependent lasing performance, with a different color at the ends and center respectively above the threshold. Meanwhile, dual‐color lasing with a wavelength separation of 35 nm is activated simultaneously at a site with an intermediate composition. This position‐dependent dual‐color lasing from a single nanowire makes these metal halide perovskites promising for applications in nanoscale optical devices.
Electron‐Blocking and Oxygen Evolution Catalyst Layers by Plasma‐Enhanced Atomic Layer Deposition of Nickel Oxide
Authors: Hufnagel Alexander G. , Henß Ann‐Kathrin , Hoffmann Ramona , Zeman Otto E. O. , Häringer Sebastian , Fattakhova‐Rohlfing Dina , Bein Thomas
Published: May 2018

A plasma‐enhanced atomic layer deposition (ALD) process is presented, capable of producing thin conformal films of nickel(II) oxide (NiO) on various substrates. Nickelocene (NiCp2) is used as an inexpensive metal precursor with oxygen plasma as the oxidant. The film growth rate saturates with both nickel precursor and plasma exposure. An ALD window is observed between 225 and 275 °C. Linear growth is achieved at 250 °C with a growth rate of 0.042 nm per cycle. The thickness is highly uniform and the surface roughness is below 1 nm rms for 52 nm thick films on Si(100). Substrates with aspect ratios up to 1:10 can be processed. As‐deposited, the films consist of polycrystalline, cubic NiO, and are transparent over the entire visible range with an optical bandgap of 3.7 eV. The films consist of stoichiometric NiO and contain ≈1% of carbon impurities. Two promising applications of these films are showcased in renewable energy conversion and storage devices: The films are pinhole‐free and exhibit excellent electron blocking capabilities, making them potential hole‐selective contact layers in solar cells. Also, high electrocatalytic activity of ultrathin NiO films is demonstrated for the alkaline oxygen evolution reaction, especially in electrolytes containing Fe3+.
Atomic Layer Deposition of Titanium Phosphate from Titanium Tetrachloride and Triethyl Phosphate onto Carbon Fibers
Authors: Militzer Christian , Buchsbaum Julia , Dzhagan Volodymyr , Zahn Dietrich R. T. , Wulff Harm , Helm Christiane A. , Goedel Werner A.
Published: May 2018

A thermal atomic layer deposition (ALD) process for depositing titanium phosphate onto bundles of carbon fibers as well as flat silicon and germanium substrates using titanium tetrachloride and triethyl phosphate as precursors is presented. This process yields conformal coatings on all substrates used while having a growth per cycle of 0.22 nm cycle−1, which is relatively high compared to other metal phosphate ALD processes. The reactions of the precursors with the surface are shown to be self‐limiting at 200 °C. Compositional analysis of the coating is performed using energy‐dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, and Fourier‐transform infrared spectroscopy. It is shown that the as‐deposited coating has a chemical composition of Ti3.0PO8.2 and a residual carbon content of 7%. Upon thermal annealing in air, residual triethyl phosphate and water is lost from the coating and phosphate can be identified up to 1000 °C. At temperatures exceeding 1000 °C, the coating starts to decompose. Thermogravimetric analysis of coated carbon fibers shows that the coating increases the onset temperature of the carbon fiber oxidation, thus providing an oxidation protection to the fibers.
Palladium (II)‐Catalyzed Decarboxylative Cross‐Dehydrogenative Coupling: Direct Synthesis of meta‐Substituted Biaryls from Aromatic Acids
Authors: Pu Fan , Zhang Lin‐Yan , Liu Zhong‐Wen , Shi Xian‐Ying
Published: May 2018

A palladium‐catalyzed tandem process of simple aromatic acids has been achieved to afford meta‐substituted biaryls in moderate to good yields. The reaction proceeds via carboxyl‐directed intermolecular cross‐dehydrogenative coupling and subsequent decarboxylation. The new C−C bonds in this transformation are formed in the ortho position of carboxyl and the reaction tolerates electron‐rich acids. Both symmetrical and unsymmetrical meta‐substituted biaryls can be directly synthesized via this method.

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Charge Pair Separation Dynamics in Organic Bulk‐Heterojunction Solar Cells
Authors: Albes Tim , Gagliardi Alessio
Published: May 2018

Charge pair separation in organic bulk‐heterojunction (BHJ) solar cells is a complex interplay between numerous factors, such as the spatial geometry of the blend, the distribution of energetic disorder, the electric field, thermal fluctuations, and the mutual electron–hole Coulomb attraction. Insufficient separation from the interface and concomitant charge pair recombination is a main limitation in improving the PCE of organic BHJ solar cells and requires an in‐depth understanding of the timescales involved. Here, a 3D kinetic Monte Carlo model of a BHJ organic solar cell is set up and the time‐dependent evolution of mutual electron–hole pair distances separating from the heterojunction interface is investigated. Large fluctuations in separation times are found, in particular in dependence of the energetic disorder and the permittivity of the organic materials. At commonly observed values of energetic disorder, slight modifications of the permittivity can drastically influence the charge separation time and even outweigh orders of magnitude of geminate recombination rates, hence help to suppress geminate recombination. Thus, the results strongly support the recent trend of developing high‐permittivity organic materials for solar cell applications.
Effects of night duty events on blood pressure and autonomic modulation in physicians
Authors: Lee Hsiu‐Hao , Chen Bing‐Yu , Pan Shih‐Chun , Lo Shih‐Hsiang , Chen Pau‐Chung , Guo Yue Leon
Published: May 2018

Background

The dynamic effects of duty events on the blood pressure (BP) and heart rate variability (HRV) of physicians on duty are unknown.

Methods

A study was conducted among 12 physicians on night duty. BP and HRV with and without the effect of a duty event were compared. The risk of higher BP and impaired HRV after a phone call were calculated.

Results

Physicians had higher mean BP (122.4 ± 11.1; 76.9 ± 7.1 mmHg) within 30 min after a phone calls than without a phone call (113.5 ± 5.3; 69.0 ± 3.8) and higher sympathetic tone (low frequency normalized units (LFnu) 68.5 ± 8.9; high frequency normalized units (HFnu) 27.7 ± 8.7) within 10 min of a phone call than without a phone call (62.9 ± 8.51; 33.5 ± 8.4). Elevated BP and sympathetic tone recovered to baseline levels 30 min after a phone call.

Conclusions

Among physicians on night duty, sympathetic tone and BP might be elevated by clinical events, and these effects last for 30 min.
BF3‐Catalyzed Synthesis of Cyclic Carbamates from Boc‐Protected Aminals and Alkynes
Authors: Kano Taichi , Yasumoto Kento , Maruoka Keiji
Published: May 2018

Cyclic carbamates were synthesized by the acid‐catalyzed reaction between Boc‐protected aminals as an imine precursor and 4‐methoxyphenyl‐substituted alkynes. The resulting cyclic carbamates could be converted to the one carbon ring‐contracted cyclic carbamates by ozonolysis. Consequently, 4‐methoxyphenyl‐substituted alkynes served as masked acyl anion equivalents.
Enzyme‐Free Replication with Two or Four Bases
Authors: Hänle Elena , Richert Clemens
Published: May 2018

All known forms of life encode their genetic information in a sequence of bases of a genetic polymer and produce copies through replication. How this process started before polymerase enzymes had evolved is unclear. Enzyme‐free copying of short stretches of DNA or RNA has been demonstrated using activated nucleotides, but not replication. We have developed a method for enzyme‐free replication. It involves extension with reversible termination, enzyme‐free ligation, and strand capture. We monitored nucleotide incorporation for a full helical turn of DNA, during both a first and a second round of copying, by using mass spectrometry. With all four bases (A/C/G/T), an “error catastrophe” occurred, with the correct sequence being “overwhelmed” by incorrect ones. When only C and G were used, approximately half of the daughter strands had the mass of the correct sequence after 20 copying steps. We conclude that enzyme‐free replication is more likely to be successful with just the two strongly pairing bases than with all four bases of the genetic alphabet.
Iridium‐Catalyzed, Silyl‐Directed, peri‐Borylation of C−H Bonds in Fused Polycyclic Arenes and Heteroarenes
Authors: Su Bo , Hartwig John F.
Published: May 2018

peri‐Disubstituted naphthalenes exhibit interesting physical properties and unique chemical reactivity, due to the parallel arrangement of the bonds to the two peri‐disposed substituents. Regioselective installation of a functional group at the position peri to 1‐substituted naphthalenes is challenging due to the steric interaction between the existing substituent and the position at which the second one would be installed. We report an iridium‐catalyzed borylation of the C−H bond peri to a silyl group in naphthalenes and analogous polyaromatic hydrocarbons. The reaction occurs under mild conditions with wide functional group tolerance. The silyl group and the boryl group in the resulting products are precursors to a range of functional groups bound to the naphthalene ring through C−C, C−O, C−N, C−Br and C−Cl bonds.
Versatile Nanostructures from Rice Husk Biomass for Energy Applications
Authors: Wang Zhaofeng , Smith Andrew T. , Wang Weixing , Sun Luyi
Published: May 2018

Converting biomass into valuable products has great benefits in terms of both economic and environmental considerations, and has attracted considerable attention in recent years. Rice husk biomass was initially utilized to produce bulk materials for conventional applications while a variety of advanced nanostructures (NSs) have been fabricated over the past few years. In addition to their low cost and environmental friendliness, RH‐derived NSs (RH‐NSs) exhibit versatile properties, which are promising for broad applications in various fields. In this Review, we summarize the latest research on RH‐NSs, covering their design, fabrication, properties, and applications in the modern energy field. Based on the unique structure and components of RHs, a series of carbon/silicon‐based novel NSs with outstanding performances have been exploited, which are difficult to be synthesized using conventional chemical reagents. We also discuss perspective uses of RH‐NSs on the basis of the current research progress.
A Smart Sensing Method for Object Identification Using Circularly Polarized Luminescence from Coordination‐Driven Self‐Assembly
Authors: Imai Yuki , Nakano Yuka , Kawai Tsuyoshi , Yuasa Junpei
Published: May 2018

The potential use of circularly polarized luminescence for object identification in a sensor application is demonstrated. New luminescence probes using pyrene derivatives as sensor luminophores were developed. (R,R)‐Im2Py and (S,S)‐Im2Py contain two chiral imidazole moieties at 1,6‐positions through ethynyl spacers (angle between spacers ca. 180°). The probe molecules spontaneously self‐assemble into chiral stacks (P or M helicity) upon coordination to metal ions with tetrahedral coordination (Zn2+). The chiral probes display neither circular dichroism (CD) nor circularly polarized luminescence (CPL) without metal ions. However, (R,R)‐Im2Py and (S,S)‐Im2Py exhibit intense chiroptical activity (CD and CPL) upon self‐assembly with Zn2+ ions. (R,R)‐Im2Py and (S,S)‐Im2Py with chemical stimuli‐responsibility allow sensing using the CPL signal as detection output, enabling us to discriminate between a signal from the target analyte and that from non‐target species.
Privacy concerns in China's smart city campaign: The deficit of China's Cybersecurity Law
Authors: Yang Fan , Xu Jian
Published: May 2018

Many cities around the world are increasingly embedding technological infrastructure in urban spaces. These infrastructures aim to collect vast amounts of data from citizens with an apparent purpose of improving public services. This article discusses privacy concerns generated by China's nationwide smart city campaign and further investigates why China's latest Cybersecurity Law is not adequate to address the risks to citizens' privacy. We argue that there is no functional privacy law in China that would apply to most data collected by smart city infrastructure; nor is there any law that would protect any personal data collected under this framework. We therefore propose practical suggestions to better protect citizens' data in China's ongoing smart city campaign.
A fuzzy clustering‐based denoising model for evaluating uncertainty in collaborative filtering recommender systems
Authors: Zhu Jun , Han Lixin , Gou Zhinan , Yuan Xiaofeng
Published: May 2018

Recommender systems are effective in predicting the most suitable products for users, such as movies and books. To facilitate personalized recommendations, the quality of item ratings should be guaranteed. However, a few ratings might not be accurate enough due to the uncertainty of user behavior and are referred to as natural noise. In this article, we present a novel fuzzy clustering‐based method for detecting noisy ratings. The entropy of a subset of the original ratings dataset is used to indicate the data‐driven uncertainty, and evaluation metrics are adopted to represent the prediction‐driven uncertainty. After the repetition of resampling and the execution of a recommendation algorithm, the entropy and evaluation metrics vectors are obtained and are empirically categorized to identify the proportion of the potential noise. Then, the fuzzy C‐means‐based denoising (FCMD) algorithm is performed to verify the natural noise under the assumption that natural noise is primarily the result of the exceptional behavior of users. Finally, a case study is performed using two real‐world datasets. The experimental results show that our proposal outperforms previous proposals and has an advantage in dealing with natural noise.
Visible‐Light‐Driven Chemoselective Hydrogenation of Nitroarenes to Anilines in Water through Graphitic Carbon Nitride Metal‐Free Photocatalysis
Authors: Xiao Gang , Li Peifeng , Zhao Yilin , Xu Shengnan , Su Haijia
Published: May 2018

Green and efficient procedures are essential for the chemoselective hydrogenation of functionalized nitroarenes to form industrially important anilines. Herein, it is shown that visible‐light‐driven, chemoselective hydrogenation of functionalized nitroarenes with groups sensitive to forming anilines can be achieved in good to excellent yields (82–100 %) in water under relatively mild conditions and catalyzed by low‐cost and recyclable graphitic carbon nitride. The process is also applicable to gram‐scale reaction, with a yield of aniline of 86 %. A study of the mechanism reveals that visible‐light‐induced electrons are responsible for the hydrogenation reactions, and thermal energy can also promote the photocatalytic activity. A study of the kinetics shows that this reaction possibly occurs through one‐step hydrogenation or stepwise condensation routes. A wide range of applications can be expected for this green, efficient, and highly selective photocatalysis system in reduction reactions for the synthesis of fine chemicals.
Novel AgCl/Ag2SO3 Hybrids as a Visible‐Light‐driven Photocatalyst: Preparation, Characterization, and Degradation of Rhodamine‐B and Methyl Orange
Authors: Wu Xiang‐Feng , Wang Yi‐Jin , Cao Zuo‐Lin , Feng Yan‐Mei , Li Hui , Zhang Chen‐Xu , Su Jun‐Zhang , Zhang Jia‐Rui , Wang Yi‐Wei , Wang Kai‐Yuan , Sun Guo‐Wen
Published: May 2018

The novel AgCl/Ag2SO3 hybrids as an efficient photocatalyst had been fabricated by an in situ synthetic method. The correlations between the structure and the photocatalytic properties of the as‐fabricated hybrids were analyzed. Experimental results exhibited that with increasing the amount of Ag2SO3, the degradation rate of the as‐obtained samples was firstly increased and then decreased under the visible light irradiation. When the mass ratio of AgCl to Ag2SO3 was 1:2, in 30 min, it displayed the highest degradation rate of 99.2% for rhodamine‐B, which was obviously higher than 46.1, 60.5, and 14.6% of pure AgCl, Ag2SO3, and TiO2 (P25), respectively. Similar results could be found in degradation of methyl orange. It had the maximum of 97.4% in 90 min, which was higher than 55.2, 48.7, and 12.7% of pure AgCl, Ag2SO3, and P25, respectively. Moreover, the as‐prepared hybrids possessed the enhanced separation and transfer of photo‐generated electron–hole pairs compared to the pure samples. In addition, the holes and superoxide radicals played the dominant role and the hydroxyl radicals played the secondary role during the process of photocatalytic degradation.
Pharmacokinetic and metabolism studies of bavachinin through ultra‐high‐performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry
Authors: Qian Jun , Xie Fan , Shi Yanhong , Li Jinhang , Zhang Liuqiang , Li Yiming , Guo Fujiang , Wang Rui
Published: May 2018

Bavachinin (BVC), one of the main bioactive prenylated flavonoids derived from Psoralea corylifolia Linn, has a wide variety of pharmacological effects, such as antiangiogenic, antitumor, antiallergic, anti‐inflammatory and antibacterial activities, especially as a pan‐peroxisome proliferator‐activated receptors agonist. A rapid and sensitive method for quantifying BVC in rat plasma was developed and validated through ultra‐high‐performance liquid chromatography coupled with electrospray‐ionization tandem mass spectrometry. Furthermore, a complete metabolic investigation of BVC was performed through ultra‐high‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry. In the pharmacokinetic analysis, BVC exhibited rapid oral absorption (Tmax = 0.68 ± 0.21 h), good elimination (T1/2 = 2.27 ± 1.63 h) following oral administration and poor absolute bioavailability (5.27%). Moreover, 11 metabolites of BVC in plasma, urine, bile and feces were characterized. The main metabolic pathways of BVC involved isomeriszation, glucuronidation, sulfonation, hydroxylation, methoxylation and reduction. In conclusion, the present study provides a sensitive quantitative method with a lower limit of quantification of 1 ng/mL and an improved comprehension of the physiological disposition of BVC.
Role of amylolytic activities during pregermination on rice kernel morphology and physicochemical properties of isolated starch
Authors: Kupkanchanakul Warunee , Thongngam Masubon , Shi Yong‐Cheng , Naivikul Onanong
Published: May 2018

Background and objectives

The role of amylolytic activities during four stages of pregermination varying on embryonic growth length between 0.5 and 7.0 mm on dynamic changes of rice kernel morphology and chemical composition, crystallinity, and thermal properties of isolated starches from three different Thai rice cultivars—SPT1 (waxy), PTT1 (low amylose), and PNL2 (high amylose)—were investigated.

Findings

Amylolytic activities of all rice cultivars significantly increased at each progressive stage, whereas SPT1 showed the highest increase in alpha‐amylase activity as the first stage of pregermination. Scanning electron micrographs showed the radial crack of kernel, appearance of individual and nonuniform starch granules after pregermination, particularly of the SPT1 cultivar. Molecular weight distribution of pregerminated brown‐rice starch (PGBRS) indicated the partial hydrolysis of starch molecules especially amylopectin, resulting in a decrease fraction of high MW molecules after pregermination. All PGBRS had A‐type X‐ray diffraction patterns with higher relative crystallinity than their natives, except that of PNL2 cultivar. Pregermination led to the change onset temperature (To) of starch gelatinization (gel_p1) and retrograded amylopectin melting (ret_p1) of PGBRS for all rice cultivars and peak temperature (Tp) of gel_p1 and ret_p1 of PGBRS for only SPT1 cultivar, whereas SPT1 was found at the lower stage than other cultivars. PGBRS at the second and third stage for SPT1, after the third stage for PTT1, and after the second stage for PNL2 had lower enthalpy (ΔH) of ret_p1 than their natives.

Conclusions

Alpha‐amylase activity plays a role in partial hydrolysis of amylopectin at amorphous region during rice pregermination which resulted in significant changes of thermal properties for all rice, especially SPT1 cultivar. Pregermination with 2–3‐mm EGL of all rice could be used as starch bio‐modification to obtain a lower retrograded starch as a functional ingredient of rice‐based products.

Significance and novelty

The change in thermal properties of waxy SPT1 rice cultivar, which mostly contained amylopectin and highly increased alpha‐amylase activity after first stage of pregermination, was more pronounced than those of nonwaxy PTT1 and PNL2 rice cultivars.
Recycling Antibiotic Bacterial Residues for Application in High‐Performance Lithium−Sulfur Batteries
Authors: Wang Qian , Zhong Hui , Jiang Min , Liao Qunchao , Yang Juan , Zhou Xiangyang , Tang Jingjing
Published: May 2018

Antibiotic bacterial residue is a type of hazardous waste generated during the extraction of antibiotic. Owing to the large amount, difficult disposal, and negative impacts on the environment and human health of antibiotic bacterial residues, it is of great significance to find an efficient treatment and resource technology. In an effort to recycle antibiotic bacterial residues from “trash to treasure” and to target a high‐value application, antibiotic bacterial residues are utilized for the fabrication of nitrogen‐doped porous carbon, which are then used to modify a separator in the configuration of lithium–sulfur batteries. Owing to the high level of nitrogen doping, large surface area, and abundant pores, the obtained lithium–sulfur batteries deliver a high initial discharge capacity of 1426 mAh g−1 at 0.2 C and a low fading rate of 0.077 % per cycle within 700 cycles at 0.5 C with pure sulfur cathode.
Hierarchical Bi2Te3 Nanostrings: Green Synthesis and Their Thermoelectric Properties
Authors: Liu Yu , Wang Qishun , Pan Jing , Sun Yabin , Zhang Lingling , Song Shuyan
Published: May 2018

Bi2Te3 hierarchical nanostrings have been synthesized through a solvothermal approach with the assistance of sucrose. The hierarchical Bi2Te3 was supposed to be fabricated through a self‐assembly process. Te nanorods first emerge with the reduction of TeO32− followed by heterogeneous nucleation of Bi2Te3 nanoplates on the surface and tips of Te nanorods. Te nanorods further transform into Bi2Te3 nanorods simultaneously with the nanoplates’ growth leading to a hierarchical structure. By controlling the reaction kinetics by adding different amount of ethylene glycol, the length of nanorods and the number of nanoplates could be tailored. The use of sucrose is vital to the formation of hierarchical structure because it not only serves as a template for the well‐defined growth of Te nanorods but also promotes the heterogeneous nucleation of Bi2Te3 in the self‐assembly process. The Bi2Te3 nanomaterial shows a moderate thermoelectric performance because of its hierarchical structure. This study shows a promising way to synthesize Bi2Te3‐based nanostructures through environmental friendly approach.
Surface‐enhanced chiroptical spectroscopy with superchiral surface waves
Authors: Pellegrini Giovanni , Finazzi Marco , Celebrano Michele , Duò Lamberto , Biagioni Paolo
Published: May 2018

We study the chiroptical properties of one‐dimensional photonic crystals supporting superchiral surface waves by introducing a simple formalism based on the Fresnel reflection matrix. We show that the proposed framework provides useful insights on the behavior of all the relevant chiroptical quantities, allowing for a deeper understanding of surface‐enhanced chiral sensing platforms based on one‐dimensional photonic crystals. Finally, we analyze and discuss the limitations of such platforms as the surface concentration of the target chiral analytes is gradually increased.
The (Dis)Advantage of Friendship on Information Search and Satisfaction
Authors: Kwon Ohjin , Walsh Darlene , Kim Hakkyun
Published: May 2018

Across four experiments, and focusing on consumer behaviour in a high uncertainty market (i.e., a used car market), this research shows that prior to a purchase, buyers are less motivated to search for information when they purchase a product from a friend (compared to someone they do not know). We also show that buyers are more willing to search for information after a transaction when sellers are their friends, a reversal in search behaviour due to the greater social risk that buyers bear when dealing with a friend. Finally, this research shows that both the transaction outcome (i.e., positive versus negative) and the buyer–seller relationship determine the degree to which people are satisfied or dissatisfied with a seller. Copyright © 2018 ASAC. Published by John Wiley & Sons, Ltd.
Hyperpolarized Porous Silicon Nanoparticles: Potential Theragnostic Material for 29Si Magnetic Resonance Imaging
Authors: Seo Hyeonglim , Choi Ikjang , Whiting Nicholas , Hu Jingzhe , Luu Quy Son , Pudakalakatti Shivanand , McCowan Caitlin , Kim Yaewon , Zacharias Niki , Lee Seunghyun , Bhattacharya Pratip , Lee Youngbok
Published: May 2018

Porous silicon nanoparticles have recently garnered attention as potentially‐promising biomedical platforms for drug delivery and medical diagnostics. Here, we demonstrate porous silicon nanoparticles as contrast agents for 29Si magnetic resonance imaging. Size‐controlled porous silicon nanoparticles were synthesized by magnesiothermic reduction of silica nanoparticles and were surface activated for further functionalization. Particles were hyperpolarized via dynamic nuclear polarization to enhance their 29Si MR signals; the particles demonstrated long 29Si spin‐lattice relaxation (T1) times (∼25 mins), which suggests potential applicability for medical imaging. Furthermore, 29Si hyperpolarization levels were sufficient to allow 29Si MRI in phantoms. These results underscore the potential of porous silicon nanoparticles that, when combined with hyperpolarized magnetic resonance imaging, can be a powerful theragnostic deep tissue imaging platform to interrogate various biomolecular processes in vivo.
Detection of Refined Sunflower and Rapeseed Oil Addition in Cold Pressed Rapeseed Oil Using Mid Infrared and Raman Spectroscopy
Authors: McDowell Daniel , Osorio Maria Teresa , Elliott Christopher T. , Koidis Anastasios
Published: May 2018

In this study, a new screening technique for the detection of two types of oil adulterants in cold pressed rapeseed oil is investigated. The calibration models built with four different multivariate classifiers (SIMCA, PLS‐DA, LDA‐KNN, and LDA‐SVM) are based on spectral fingerprints from either FT‐IR and Raman instruments from authentic pure oils and in‐house admixtures of the oils involved. When refined sunflower oil is the adulterant, both FT‐IR and Raman produce effective models with high sensitivity of 86% and 93% respectively. When refined rapeseed oil is the adulterant the sensitivity decreases. This is explained by the chemical differences of the two adulterants. PLS‐R quantification analysis estimates minimum detection levels of 15% (Raman) and 9% (FT‐IR) when refined sunflower oil is the adulterant, and 22% (Raman) and 64% (FT‐IR) when refined rapeseed oil is the adulterant. This initial study shows the potential of Raman spectroscopy to be utilized for the screening of cold pressed rapeseed oil authenticity.

Practical Applications: It has been well documented in the past that high‐value edible oils can be easily adulterated with lower cost oils for economic gain. Although the cold pressed rapeseed oil industry has not experienced such fraud, it would be prudent to have analytical techniques available to authenticate genuine oils quickly. This would further strengthen cold pressed rapeseed oil's reputation as a product free from substitutional fraud. These calibration models can tool the industry and regulatory bodies with a screening method to detect authenticity in realistic levels.

A feasibility study regarding cold pressed rapeseed oil adulteration is investigated. Cold pressed rapeseed oil is adulterated with either refined rapeseed oil or refined sunflower oil and spectra is acquired using either Raman or FT‐IR spectroscopy. A library of spectra is gathered which includes pure cold pressed rapeseed oil and cold pressed rapeseed oil admixtures of varying concentrations. Chemometric analysis is carried out on the dataset with both classification and quantification techniques. The optimum instrument‐chemometric pairings for cold pressed rapeseed oil authentication are discussed.
Temperature‐Dependent Cinchona Alkaloid Squaramide‐Catalyzed Asymmetric Formal [3+2] Cycloaddition of Isocyanoacetates with β‐Trifluoromethylated Enones
Authors: Zhao Mei‐Xin , Zhu Guang‐Yu , Zhu Hui‐Kai , Zhao Xiao‐Li , Ji Ming , Shi Min
Published: May 2018

An efficient temperature‐dependent organocatalyzed asymmetric formal [3+2] cycloaddition reaction of α‐substituted isocyanoacetates to β‐trifluoromethylated enones by cinchona alkaloid‐derived squaramide has been investigated, affording the optically active trifluoromethylated 2‐pyrrolines in excellent yields (up to 98 %) and high stereoselectivities (>20:1 dr, up to >99 % ee) under mild conditions.
How the interplay of imagined contact and first‐person narratives improves attitudes toward stigmatized immigrants: A conditional process model
Authors: Igartua Juan‐José , Wojcieszak Magdalena , Kim Nuri
Published: May 2018

This article assesses the mechanisms whereby first‐person narratives featuring stigmatized immigrants improve outgroup attitudes and encourage intergroup contact among prejudiced individuals. We rely on a 2 (imagined contact vs. control) × 2 (similar vs. dissimilar message protagonist) experiment on a systematic sample of native British adults. Results show that encouraging imagined contact prior to reading a short testimonial featuring an immigrant protagonist who is similar to the recipients in terms of social identity enhances identification with the protagonist, thereby improving outgroup attitudes and encouraging intergroup contact, and especially strongly among those who are prejudiced toward immigrants (i.e., high on modern racism). Theoretical and practical implications of the findings for the work on imagined contact, narrative persuasion, and identification, as well as for public communication campaigns, are discussed.
Implicit theories of shyness in American and Chinese children
Authors: Zhang Zengxiu , Xu Yiyuan
Published: May 2018

This study examined whether implicit theories of shyness differed between American and Chinese children and how this difference helped explain cultural variations in stereotypical views about shy children and relationship with shy peers. We found that regardless of cultural group, children's implicit theories of shyness were not related to their own shyness, but were associated with stereotypical views about shy children (positively) and relationship with shy peers (negatively). American children reported stronger entity theories of shyness, i.e., they were more likely to view shyness as a stable and immutable trait than Chinese children, which partly explained why they had worse relationships with shy peers. These findings highlight the important roles implicit theories may play in understanding cultural similarities and differences in interpersonal perception and relationship.
Valproic acid utilization among girls and women in Stockholm: Impact of regulatory restrictions
Authors: Karlsson Lind Linnéa , Komen Joris , Wettermark Björn , von Euler Mia , Tomson Torbjörn
Published: May 2018

Objective

In November 2014, the European Medicines Agency (EMA) strengthened restrictions on the use of valproic acid in girls and women of childbearing potential. The objective of this study was to determine whether there has been a change in initiations of valproic acid treatment to females after the regulatory restrictions and to assess if such changes differed between indications (epilepsy and psychiatric disorder).

Methods

An interrupted time‐series analysis was conducted using all initiations of valproic acid in Stockholm, Sweden. from January 2011 to June 2017. Female and male patients aged 0–45 years with a recorded diagnosis of epilepsy and/or a psychiatric disorder were compared.

Results

Before the EMA warning, a decline in trend of valproic acid initiations was seen in patients with epilepsy. After the warning, a significant decrease of valproic acid initiations was seen in women with a psychiatric disorder, but not in women with epilepsy.

Significance

The regulatory warning appeared to have significantly influenced valproic acid initiations in women of childbearing age with a psychiatric disorder. No effect was seen in women with epilepsy, probably because the decline had started long before.
Correction factors for SSI effects predicted by simplified models: 2D versus 3D rectangular embedded foundations
Authors: Fu Jia , Todorovska Maria I. , Liang Jianwen
Published: May 2018

The effects of soil‐structure interaction (SSI) are often studied using two‐dimensional (2D) or axisymmetric three‐dimensional (3D) models to avoid the high cost of the more realistic, fully 3D models, which require 2 to 3 orders of magnitude more computer time and storage. This paper analyzes the error and presents correction factors for system frequency, system damping, and peak amplitude of structural response computed using impedances for linear in‐plane 2D models with rectangular foundations, embedded in uniform or layered half‐space. They are computed by comparison with results for 3D rectangular foundations with the same vertical cross‐section and different aspect ratios. The structure is represented by a single degree‐of‐freedom oscillator. Correction factors are presented for a range of the model parameters. The results show that in‐plane 2D approximations overestimate the SSI effects, exaggerating the frequency shift, the radiation damping, and the reduction of the peak amplitude. The errors are larger for stiffer, taller, and heavier structures, deeper foundations, and deeper soil layer. For example, for a stiff structure like Millikan library (NS response; length‐to‐width ratio ≈ 1), the error is 6.5% in system frequency, 44% in system damping, and 140% in peak amplitude. The antiplane 2D approximation has an opposite effect on system frequency and the same effect on system damping and peak relative response. Linear response analysis of a case study shows that the NEHRP‐2015 provisions for reduction of base shear force due to SSI may be unsafe for some structures. The presented correction factor diagrams can be used in practical design and other applications.
Supplier‐induced demand for urgent after‐hours primary care services
Authors: Longden Thomas , Hall Jane , van Gool Kees
Published: May 2018

Australia is one of nine Organisation for Economic Co‐operation and Development (OECD) countries that utilise deputising services to provide after‐hours primary care. While the provision of this service is supposed to be on behalf of regular general practitioners, businesses have adapted to the financial incentives on offer and are directly advertising their services to consumers emphasising patient convenience and no copayments. The introduction of corporate entities has changed the way that deputising services operate. We use a difference‐in‐difference approach to estimate the amount of growth in urgent after‐hours services that was not warranted by urgent medical need. These estimates are calculated by comparing the growth in urgent attendances that occurred during times of the day that are classified as “after‐hours” (e.g., 6 pm–11 pm Monday to Friday) with those that are classified as “unsociable‐hours” (e.g., 11 pm–7 am Monday to Friday). For the national level, we estimate that 593,141 unwarranted attendances were induced as urgent after‐hours consultations in a single year. This corresponds to a national estimate of the total benefits paid for unwarranted demand of approximately $77 million. While deputising services have filled a short‐fall in after‐hours services, the overuse of urgent items has meant that that this has been achieved at a considerable cost to the Australian Government.
Management of postpartum hemorrhage with free‐flow pressure controlled uterine balloon
Authors: Theron Gerhard B.
Published: May 2018

The free‐flow uterine balloon allowed water to be expelled from the balloon and intra‐uterine pressure control by adjusting the height of the supply bag.