bluuebunny/crossref_metadata_2025 huggingface dataset:
Reversible Solution π‐Dimerization and Long Multicenter Bonding in a Stable Phenoxyl Radical
Authors: Bonanno Nico M. , Poddutoori Prashanth K. , Sato Kazunobu , Sugisaki Kenji , Takui Takeji , Lough Alan J. , Lemaire Martin T.
Published: July 2018

Reversible solution π‐dimerization is observed in the stable neutral phenoxyl radical 2,6‐bis‐(8‐quinolylamino)‐4‐(tert‐butyl)phenoxyl baqp and is spectroscopically characterized. This behavior, not previously observed for π‐extended phenoxyl radicals, is relevant to the formation of long multicenter bonding in the π‐dimer at low temperature akin to previously reported phenalenyl radicals. Our experimental data are supported in a quantitative manner by results from density functional theory (DFT) and ab initio molecular orbital theory calculations. Our theoretical results indicate that the solution dimer features strong bonding interactions between the two phenoxyl rings but that the stability of the dimer is also related to dispersion interactions between the flanking nearly parallel quinolyl rings.
Sustainable Heterogeneous Catalysts for CO2 Utilization by Using Dual Ligand ZnII/CdII Metal–Organic Frameworks
Authors: Parmar Bhavesh , Patel Parth , Kureshy Rukhsana I. , Khan Noor‐ul H. , Suresh Eringathodi
Published: July 2018

Two‐dimensional ZnII/CdII‐based dual ligand metal–organic frameworks (MOFs) {[M(CHDC)(L)]⋅H2O}n involving 4‐pyridyl carboxaldehyde isonicotinoylhydrazone (L) in combination with flexible 1,4‐cyclohexanedicarboxylic acid (H2CHDC) as linkers have been synthesized by adaptable synthetic protocols including a green mechanochemical (grinding) method. Characterization, chemical/thermal stability, phase purity, and solid‐state luminescent properties of both MOFs have been established by various analytical methods. Structural analysis revealed dimeric metal clusters composed of [M2(CHDC)2]n loops doubly pillared with L, generating a 2D framework. Both MOFs can be used as highly active solvent‐free binary catalysts for CO2 cycloaddition with epoxides in the presence of the co‐catalyst tetrabutylammonium bromide (TBAB) with good catalytic conversion in up to six catalytic cycles without significant loss of activity. The present investigation demonstrates the application of MOFs as efficient heterogeneous catalysts for CO2 utilization under moderate reaction conditions. Based on the single‐crystal X‐ray data, a probable mechanism for the cycloaddition reaction has also been proposed.
Electrolytes for Batteries with Earth‐Abundant Metal Anodes
Authors: Zhao Hongyang , Xu Jun , Yin Dandan , Du Yaping
Published: July 2018

Earth‐abundant metal anodes have become one of the hottest topics in recent years. As alternatives to lithium metals, earth‐abundant metal anodes have significantly lower cost and higher energy density, but with unprecedented problems that cannot be solved by simply referring to experiences with lithium‐metal anodes. The electrolytes for these anodes greatly influence the overall performance, such as Coulombic efficiency, stability, and even the availability to become an anode. In this Minireview, some excellent state‐of‐art works on the electrolytes of energy‐storage systems with sodium‐, potassium‐, magnesium‐, calcium‐, and aluminum‐metal anodes are concisely summarized. The performance of these systems is highlighted by the rational design of the electrolyte and electrolyte/electrode interface.
Ping‐Pong Tunneling Reactions: Can Fluoride Jump at Absolute Zero?
Authors: Nandi Ashim , Sucher Adam , Kozuch Sebastian
Published: July 2018

In a recent study, Scheiner designed a double‐germanium‐based fluoride receptor that binds the halogen by means of strong tetrel bonds (Chem. Eur. J. 2016, 22, 18850). In this system the F− binds to the germanium atoms in an asymmetric fashion, thereby producing a double‐well potential in which the fluoride can jump from one germanium to the other as in a ping‐pong game. Herein we prove through the use of computational tools that at cryogenic temperatures this rearrangement occurs by heavy‐atom quantum mechanical tunneling. The inductive strength of the substituents and the polarity of the solvent can modify the barrier and the tunneling rate. But the strongest effect is observed upon modification of the geometry of the molecule by specific substitutions that affect the barrier width, the most critical factor in a tunneling mechanism. We postulate two experimental tests, one by microwave spectroscopy and one by cryogenic NMR spectroscopy, that can prove the predicted fluoride tunneling.
Direct Transformation of Arylamines to Aryl Halides via Sodium Nitrite and N‐Halosuccinimide
Authors: Mukhopadhyay Sushobhan , Batra Sanjay
Published: July 2018

A one‐pot universal approach for transforming arylamines to aryl halides via reaction with sodium nitrite (NaNO2) and N‐halosuccinimide (NXS) in DMF at room temperature under metal‐ and acid‐free condition is described. This new protocol that is complementary to the Sandmeyer reaction, is suggested to involve the in situ generation of nitryl halide induce nitrosylation of aryl amine to form the diazo intermediate which is halogenated to furnish the aryl halide.
Functionalization of Azapentabenzocorannulenes by Fivefold C−H Borylation and Cross‐Coupling Arylation: Application to Columnar Liquid‐Crystalline Materials
Authors: Nagano Taro , Nakamura Kimihiro , Tokimaru Yuki , Ito Shingo , Miyajima Daigo , Aida Takuzo , Nozaki Kyoko
Published: July 2018

Herein, the one‐shot fivefold functionalization of azapentabenzocorannulenes by an iridium‐catalyzed fivefold C−H borylation reaction that exhibits excellent regioselectivity is reported. The borylated product can be used as a versatile synthetic intermediate for further derivatization via Suzuki–Miyaura cross‐coupling reactions. This fivefold borylation/arylation sequence was employed to synthesize liquid‐crystalline azapentabenzocorannulenes with five 3,4,5‐trialkoxyphenyl groups, which assemble into 1D hexagonal columnar structures over a wide temperature range. The present method expands the variety and utility of azapentabenzocorannulenes as promising π‐conjugated cores.
Iron‐Catalyzed Alkylation of Nitriles with Alcohols
Authors: Ma Wei , Cui Suya , Sun Huamin , Tang Weijun , Xue Dong , Li Chaoqun , Fan Juan , Xiao Jianliang , Wang Chao
Published: July 2018

A general, efficient iron‐catalyzed α‐alkylation of nitriles with primary alcohols through a hydrogen‐borrowing pathway has been developed, allowing a wide variety of alkylated nitriles to be readily accessible. Detailed mechanistic studies suggest that the reaction proceeds via an olefin intermediate with the turnover rate limited by the hydrogenation of the olefin with an iron hydride. Apart from participating in the alkylation, the nitrile is found to play an important role in promoting the formation of and stabilizing the active catalytic species.
Spectrums of Nitrogen and Phosphorus Leaching Loss from Different Land‐Use Types
Authors: Wang Zhen Hong , Wan Li , Xu Chan Min
Published: July 2018

Understanding nitrogen and phosphorus leaching rates is critical for controlling non‐point source pollution. As of now, no studies have dealt with the spectrums of N or P leaching loss, a new concept is suggested in the present study, which can be used to assess the risks of N or P leaching loss. The spectrums of N or P leaching loss consist of the highest leaching loss (HLLr), mean leaching loss (MLLr), lowest leaching loss (LLLr), lowest leaching loss at an upper limit (LLLU), and lowest leaching at a lower limit (LLLL), and annual average of the lowest leaching loss (AALLL) and annual average of different‐level leaching loss (AADLL). These indices are tested with leaching experiments with distilled water, lysimeters, and PVC‐pipe method based on Darcy's law on seven land‐use types in the Dachong karst watershed in China. LLLL is similar among all land‐use types, except vegetable land. Four types of forests show few differences in LLLU and LLLL. HLLr, MLLr and LLLr, and AALLL and AADLL in the croplands are clearly greater than those in the forests. The HLLr of total nitrogen in vegetable land is highest (16.08 mg L−1) but the HLLr of nitrate nitrogen, ammonium nitrogen, and total phosphorus in paddy field are highest (11.01, 1.39, and 0.3 mg L−1, respectively). LLLr, MLLr, and HLLr in the same type of land use are one to three times higher than LLLU in N leaching loss. The spectrums intuitively show differences in N and P leaching losses among land‐use types in the karst watershed in China.
Automated Synthesis of (rac)‐, (R)‐, and (S)‐[18F]Epifluorohydrin and Their Application for Developing PET Radiotracers Containing a 3‐[18F]Fluoro‐2‐hydroxypropyl Moiety
Authors: Fujinaga Masayuki , Ohkubo Takayuki , Yamasaki Tomoteru , Zhang Yiding , Mori Wakana , Hanyu Masayuki , Kumata Katsushi , Hatori Akiko , Xie Lin , Nengaki Nobuki , Zhang Ming‐Rong
Published: July 2018

To introduce the 3‐[18F]fluoro‐2‐hydroxypropyl moiety into positron emission tomography (PET) radiotracers, we performed automated synthesis of (rac)‐, (R)‐, and (S)‐[18F]epifluorohydrin ([18F]1) by nucleophilic displacement of (rac)‐, (R)‐, or (S)‐glycidyl tosylate with 18F− and purification by distillation. The ring‐opening reaction of (R)‐ or (S)‐[18F]1 with phenol precursors gave enantioenriched [18F]fluoroalkylated products without racemisation. We then synthesised (rac)‐, (R)‐, and (S)‐ 2‐{5‐[4‐(3‐[18F]fluoro‐2‐hydroxypropoxy)phenyl]‐2‐oxobenzo[d]oxazol‐3(2H)‐yl}‐N‐methyl‐N‐phenylacetamide ([18F]6) as novel radiotracers for the PET imaging of translocator protein (18 kDa) and showed that (R)‐ and (S)‐[18F]6 had different radioactivity uptake in mouse bone and liver. Thus, (rac)‐, (R)‐, and (S)‐[18F]1 are effective radiolabelling reagents and can be used to develop PET radiotracers by examining the effects of chirality on their in vitro binding affinities and in vivo behaviour.
Microbiome Analyses for Toxicological Studies
Authors: Benjamino Jacquelynn , Beka Lidia , Graf Joerg
Published: July 2018

Microbiomes can be thought of as the integration of biotic and abiotic factors, including the microbial communities and the distinct physio‐chemical properties that are present in a habitat. The microbes within a microbiome can influence the chemical environment by degrading medications inside patients or contaminants in the environment, such as hydrocarbons released after the Deepwater Horizon oil spill. Identifying and monitoring the relative abundance of microbes can help to elucidate variations in their response to toxins and should be considered as a variable in statistical analyses. In addition, the presence of pathogenic microbes or toxin‐producing species could affect the observed toxicity of an environment. The protocols in this unit begin with the collection of samples, proceeds to sequencing of the bacterial DNA, and ends with an analysis of the bacterial community in light of environmental metadata. © 2018 by John Wiley & Sons, Inc.
Effect of Alcohol Structure on the Kinetics of Etherification and Dehydration over Tungstated Zirconia
Authors: Rorrer Julie , Pindi Suresh , Toste F. Dean , Bell Alexis T.
Published: July 2018

Linear and branched ether molecules have attracted recent interest as diesel additives and lubricants that can be produced from biomass‐derived alcohols. In this study, tungstated zirconia was identified as a selective and green solid acid catalyst for the direct etherification of primary alcohols in the liquid phase, achieving ether selectivities of >94 % for C6–C12 linear alcohol coupling at 393 K. The length of linear primary alcohols (C6–C12) was shown to have a negligible effect on apparent activation energies for etherification and dehydration, demonstrating the possibility to produce both symmetrical and asymmetrical linear ethers. Reactions over a series of C6 alcohols with varying methyl branch positions indicated that substituted alcohols (2°, 3°) and alcohols with branches on the β‐carbon readily undergo dehydration, but alcohols with branches at least three carbons away from the ‐OH group are highly selective to ether. A novel model compound, 4‐hexyl‐1dodecanol, was synthesized and tested to further demonstrate this structure–activity relationship. Trends in the effects of alcohol structure on selectivity were consistent with previously proposed mechanisms for etherification and dehydration, and help to define possible pathways to selectively form ethers from biomass‐derived alcohols.
Multilayered, Bipolar, All‐Solid‐State Battery Enabled by a Perovskite‐Based Biphasic Solid Electrolyte
Authors: Shin Hyun‐Seop , Ryu Won‐Gyue , Park Min‐Sik , Jung Kyu‐Nam , Kim Hansung , Lee Jong‐Won
Published: July 2018

The use of solid electrolytes provides a technical solution to address the safety issues of lithium‐ion batteries and enables a bipolar design of high‐voltage and high‐energy battery modules. The bipolar design avoids unnecessary components and parts for packaging and electrical connection; therefore, it facilitates an increase in the volumetric energy density of the battery, while enabling easy build‐up of total output voltage. Herein, the design and construction of a multilayered, bipolar‐type, all‐solid‐state battery (ASSB) from a biphasic solid electrolyte (BSE) based on inorganic Li0.29La0.57TiO3 perovskite and poly(ethylene oxide) (PEO) are reported. A flexible and freestanding BSE membrane exhibits high Li+ conductivity of about 1.2×10−4 S cm−1, and shows enhanced electrochemical/thermal stability, in comparison to a PEO‐only solid electrolyte. A single‐layered ASSB assembled with a BSE shows promising electrochemical performance, as evidenced by a high reversible capacity of about 123 mA h g−1 and excellent cycling stability over 100 cycles. Furthermore, a proof‐of‐concept bipolar ASSB comprising three unit cells connected in series is constructed by using the BSE membrane and Al/Cu‐cladded bipolar plates. The bipolar ASSB shows high thermal stability and operates reversibly without any internal short circuit or current leakage during charge–discharge cycles; this demonstrates that BSEs provide a promising approach to the design and fabrication of bipolar ASSBs with improved safety and high energy density.
Bio‐available Solvent Cyrene: Synthesis, Derivatization, and Applications
Authors: Camp Jason E.
Published: July 2018

The development of green solvents is one of the key tenets of Green Chemistry as solvents account for the majority of waste stemming from the production of the chemicals on which we have all come to rely. An important class of solvents is the dipolar aprotics, which include N,N‐dimethylformamide (DMF) and N‐methyl‐2‐pyrrolidone (NMP). In addition to being derived from non‐renewable resources, these solvents are also under increased regulatory pressures that will limit their industrial applications. This Concept concerns the bio‐available solvent Cyrene (dihydrolevoglucosenone) as a potential replacement for toxic dipolar aprotic solvents. An emphasis is placed on examining the strengths and weaknesses of Cyrene as a solvent and is accomplished by looking at the synthesis, derivatization, and application in synthetic protocols of Cyrene. With respect to the Twelve Principles of Green Chemistry, this Concept describes a bio‐available solvent that should have a disruptive effect on the use of traditional industrial dipolar aprotic solvents.
Expression of p63 immunostaining in liquid‐based cytology (BD SurePath) of breast fine‐needle aspiration
Authors: Osugi Masumi , Kinoshita Kosei , Sugita Atsuro , Kito Katsumi , Maeda Toshiharu
Published: July 2018

Background

We performed p63 immunostaining to detect myoepithelial cells on BD SurePath liquid‐based cytology (LBC) slides and examined whether this improved the diagnostic accuracy in breast fine‐needle aspiration cytology (FNAC).

Methods

We examined the diagnostic accuracy using the LBC‐p63 immunostaining slides of 298 lesions obtained from July 2010 to August 2016.

Results

We defined the cutoff values for malignancy as follows: (1) the percentage of p63+ cluster was <30%, (2) the percentage of p63+ single cells in cell clusters was <3%, (3) the number of p63+ single cells in the background was <20 when the total number of the cell clusters was <100, or the number was <120 when the total number was ≥100. The malignant lesions showed significantly lower values than the benign lesions in the percentage of p63+ clusters, the percentage of p63+ single cells in the clusters, and the number of p63+ single cells in the background (P < .001). The diagnostic values obtained only by Papanicolaou staining vs the improved values with LBC‐p63 immunostaining slides were as follows. Sensitivity, 88.3% to 99.0%; specificity, 89.1% to 99.0%; positive predictive value, 94.8% to 99.5%; negative predictive value, 77.4% to 97.8%; diagnostic accuracy, 88.6% to 99.0%, respectively.

Conclusion

The diagnostic accuracy of breast FNAC was significantly improved by adding LBC‐p63 immunostaining.
Sediment microfabric records mass sedimentation of colonial cyanobacteria and extensive syndepositional metazoan reworking in Pliocene sapropels
Authors: Löhr Stefan C. , Kennedy Martin J. , George Simon C. , Williamson Robyn J. , Xu Huiyuan
Published: July 2018

The sapropel record of the eastern Mediterranean provides unique insight into the primary climatic, oceanographic, and biological drivers of organic carbon enrichment in marine sediments. The dominant source of organic matter, timing of oxygen depletion at the sea floor, and extent of metazoan reworking of these deposits remain unclear. These questions are addressed by combining microbeam imaging with bulk and molecular geochemical characterization of several Pliocene sapropels, revealing four microfacies which record distinct palaeoceanographic conditions, phytoplankton assemblages, and degrees of postdepositional reworking. The most organic‐rich, carbonate‐lean sapropel intervals consist of alternating 10–60‐μm‐thick organic and detrital mineral laminae. Petrographical features consistent with a pelagic origin, δ15N <−1.8 and the presence of 2α‐methylhopanes indicate that organic laminae formed by mass sedimentation of N‐fixing colonial cyanobacteria (Trichodesmium). The association of framboidal pyrite with organic laminae suggests that mass sedimentation led to the abrupt development of sea floor anoxia. Unlike similar Quaternary sapropels, no petrographic or biomarker evidence is found for a mat‐forming diatom contribution to these organic‐rich, laminated intervals. However, episodic mass sedimentation was not found to be a universal ingredient of sapropel formation. Carbonate‐lean, weakly laminated intervals contain >50 μm organomineral aggregates, interpreted as marine snow, whereas carbonate microfossil‐rich intervals record periods of nitrogen fixation and moderately increased primary production by a diverse assemblage of calcareous, organic‐walled, and siliceous plankton. The results presented here further show that burrowing by microscopic meiofauna impacted most sapropels, extending into seemingly laminated intervals below obvious disruption from burrowing macrofauna, indicating that metazoans influence organic carbon burial in oxygen‐depleted settings even where physical displacement of sediment is not visible.
Impact of pubertal timing and depression on error‐related brain activity in anxious youth
Authors: Peters Amy T. , Burkhouse Katie L. , Kujawa Autumn , Afshar Kaveh , Fitzgerald Kate D. , Monk Christopher S. , Hajcak Greg , Phan K. Luan
Published: July 2018

Anxiety disorders are associated with enhanced error‐related negativity (ERN) across development but it remains unclear whether alterations in brain electrophysiology are linked to the timing of puberty. Pubertal timing and alterations of prefrontal and limbic development are implicated in risk for depression, but the interplay of these factors on the ERN–anxiety association has not been assessed. We examined the unique and interactive effects of pubertal timing and depression on the ERN in a sample of youth 10–19 years old with anxiety disorders (n = 30) or no history of psychopathology (n = 30). Earlier pubertal maturation was associated with an enhanced ERN. Among early, but not late maturing youth, higher depressive symptoms were associated with a reduced ERN. The magnitude of neural reactivity to errors is sensitive to anxiety, depression, and development. Early physical maturation and anxiety may heighten neural sensitivity to errors yet predict opposing effects in the context of depression.
Hair analysis can provide additional information in doping and forensic cases involving clostebol
Authors: Salomone Alberto , Gerace Enrico , Di Corcia Daniele , Alladio Eugenio , Vincenti Marco , Kintz Pascal
Published: July 2018

Clostebol is a synthetic anabolic androgenic steroid, with potential use as a performance‐enhancing drug if taken for long periods in order to produce the desired effect. Recently, the use of medications containing clostebol acetate has led to the suspension of several athletes in various sports. Previous studies have shown that urine can result positive in case of single intake of a banned substance, including unintentional consumption of steroids. In this context, a hair test can contribute to exculpation of athletes by demonstrating alternative administration or contamination. The development and validation of an ultra‐high performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method to detect clostebol and clostebol acetate in hair is hereby presented. Some real cases of athletes sanctioned for clostebol use, in which we analyzed hair samples to follow up investigations of doping control laboratories and obtain useful elements to understand the origin of clostebol intakes, and two forensic cases of anabolic drugs abuse, are also presented and discussed. In real head‐ and body‐hair samples, clostebol acetate could be detected in the low pg/mg range. As is typical of hair analysis, the interpretation of the quantitative findings may be challenging, and even more in sports owing to the lack of systematic studies. However, the results can be used to produce evidence contrary to any ruling issued against the athletes by the appropriate sports body, and possibly obtain a diminished sanction. Because the sports authorities do not make a distinction among circumstances or means of administration of anabolic compounds, athletes should be warned not to use clostebol‐containing medications.
Quantifying carbon stocks in shifting cultivation landscapes under divergent management scenarios relevant to REDD+
Authors: Borah Joli R. , Evans Karl L. , Edwards David P.
Published: July 2018

Shifting cultivation dominates many tropical forest regions. It is expanding into old‐growth forests, and fallow period duration is rapidly decreasing, limiting secondary forest recovery. Shifting cultivation is thus a major driver of carbon emissions through deforestation and forest degradation, and of biodiversity loss. The impacts of shifting cultivation on carbon stocks have rarely been quantified, and the potential for carbon‐based payments for ecosystem services (PES), such as REDD+, to protect carbon in shifting cultivation landscapes is unknown. We present empirical data on aboveground carbon stocks in old‐growth forest and shifting cultivation landscapes in northeast India, a hotspot of threatened biodiversity. We then model landscape‐level carbon stocks under business‐as‐usual scenarios, via expansion into the old‐growth forest or decreasing fallow periods, and intervention scenarios in which REDD+ is used to either reduce deforestation of primary or secondary forest or increase fallow period duration. We found substantial recovery of carbon stocks as secondary forest regenerates, with a 30‐yr fallow storing about one‐half the carbon of an old‐growth forest. Business‐as‐usual scenarios led to substantial carbon loss, with an 80% reduction following conversion of old‐growth forest to a 30‐yr shifting cultivation cycle and, relative to a 30‐yr cultivation landscape, a 70% reduction when switching to a 5‐yr cultivation cycle. Sparing old‐growth forests from deforestation using protected areas and intensifying cropping in the remaining area of shifting cultivation is the most optimal strategy for carbon storage. In areas lacking old‐growth forest, substantial carbon stocks accumulate over time by sparing fallows for permanent forest regeneration. Successful implementation of REDD+ in shifting cultivation landscapes can help avert global climate change by protecting forest carbon, with likely co‐benefits for biodiversity.
The effect of multiple biotic interaction types on species persistence
Authors: García‐Callejas David , Molowny‐Horas Roberto , Araújo Miguel B.
Published: July 2018

No species can persist in isolation from other species, but how biotic interactions affect species persistence is still a matter of inquiry. Is persistence more likely in communities with higher proportion of competing species, or in communities with more positive interactions? How do different components of community structure mediate this relationship? We address these questions using a novel simulation framework that generates realistic communities with varying numbers of species and different proportions of biotic interaction types within and across trophic levels. We show that when communities have fewer species, persistence is more likely if positive interactions—such as mutualism and commensalism—are prevalent. In species‐rich communities, the disproportionate effect of positive interactions on persistence is diluted and different combinations of biotic interaction types can coexist without affecting persistence significantly. We present the first theoretical examination of how multiple‐interaction networks with varying architectures relate to local species persistence, and provide insight about the underlying causes of stability in communities.
Metabolic wiring of murine T cell and intraepithelial lymphocyte maintenance and activation
Authors: Veldhoen Marc , Blankenhaus Birte , Konjar Špela , Ferreira Cristina
Published: July 2018

Adaptive immunity critically depends on cell migration combined with clonal selection and rapid expansion of rare lymphocytes recognising their cognate antigen in secondary lymphoid organs. It has since become apparent that large populations of T cells are maintained in tissues, which do not migrate throughout the body and do not require clonal expansion. Murine intraepithelial lymphocytes (IELs), located in the skin and small intestines, are maintained in a state of semi‐activation, in marked contrast to the quiescent condition naive and memory lymphocytes are kept in. The poised activation state of IELs, their location in the top layers of barrier organs and close bidirectional interactions with epithelial cells suggests IELs are part of a sophisticated strategy of immune‐surveillance and compartmentalisation of immune responses. Recent murine studies have reemphasised the influence of metabolism in T‐cell activation and differentiation, with different metabolic make up of naive, effector and memory T cells. Here we highlight and discuss some of the current insights on immunometabolism of IELs, with emphasis on novel data contrasting how IELs may be maintained in a semi‐activated state and may become fully functional compared with conventional T cells.
Interfacial Chemistry of Low‐Dimensional Systems for Applications in Nanocatalysis
Authors: Agnoli Stefano
Published: July 2018

Interfacial chemistry is a fundamental aspect of low‐dimensional systems and its comprehension is of pivotal importance for the design of composite materials with advanced properties especially in the field of nanocatalysis. The study of interfaces however, is extremely challenging since it requires the use of techniques capable of providing structural and chemical information with spatial resolution. This calls for the combination of several advanced characterization techniques and the use of carefully designed model systems. By reviewing different types of systems such as metals/oxides, oxides/oxides and 2D materials, we elucidate some key concepts that exemplify the enormous potential of interfaces. In particular, we show how interfaces can (i) stabilize unconventional morphological, chemical and structural features, (ii) be at the origin of new phenomena such as electron tunneling and unexpected reactivity and (iii) be used as functional elements able to store or separate electron charges.
PdII‐Catalyzed Purine‐Directed Ortho Nitration of 6‐Arylpurines by C(sp2)–H Activation: A Practical Approach to Synthesize 6‐(2‐Nitroaryl)‐Purine Derivatives
Authors: Gou Quan , Li Wenxi , Zhao Qingsheng , Xie Jia , Luo Ping , Cao Guang , Chen Suiyun , Qin Jun
Published: July 2018

Herein we report a method for PdII‐catalyzed purine‐directed ortho nitration of 6‐arylpurines via C(sp2)–H activation by using tBuONO/O2 as nitration agent. This procedure is highly efficient and produces a range of 6‐(2‐nitroaryl)‐purine derivatives with good chemoselectivity and functional‐group tolerance. The utility of the method is further illustrated in the synthesis of antibacterial agent.
Far‐Red‐ to NIR‐Emitting Adamantyl‐Functionalized Squaraine Dye: J‐Aggregation, Dissociation, and Cell Imaging
Authors: Liu Taihong , Liu Xinglei , Zhang Yuanwei , Bondar Mykhailo V. , Fang Yu , Belfield Kevin D.
Published: July 2018

Squaraine dyes AM‐1′ and AM‐1 bearing adamantyl termini were synthesized and spectroscopically characterized. AM‐1′ exhibited intense absorption and sharp emission in the far‐red to near‐infrared (NIR) spectral region. The degenerate two‐photon absorption (2PA) spectrum of AM‐1′ was obtained over a broad spectral range with a maximum cross section of ca. 360 GM. In aqueous solutions, AM‐1′ displayed a strong tendency for J‐aggregation and the reference AM‐1 exhibited entirely different aggregation behavior. We conclude that both the terminal pendant groups and substituents adjacent to the squaraine core play important roles in determining the aggregation behaviors and optical properties of the resultant squaraine dyes. Further an AM‐1′/β‐cyclodextrin complex dramatically suppressed squaraine π–π stacking and dissociated the J‐aggregate. Fluorescence microscopy imaging of HCT 116 cells incubated with the complex was accomplished, suggesting the potential application of this complex in fluorescence bioimaging.
Uricase Based Enzymatic Biosensor for Non‐invasive Detection of Uric Acid by Entrapment in PVA‐SbQ Polymer Matrix
Authors: RoyChoudhury Sohini , Umasankar Yogeswaran , Hutcheson Joshua D. , Lev‐Tov Hadar A. , Kirsner Robert S. , Bhansali Shekhar
Published: July 2018

In this work, an electrochemical approach using uricase (UOx) as an enzyme to detect uric acid (UA) for wound monitoring has been reported. UOx was entrapped in poly (vinyl alcohol) N‐methyl‐4(4’‐formylstyryl) pyridinium methosulfate acetal (PVA‐SbQ), a cationic polymer matrix. The polymer‐enzyme ratio for immobilization was calculated as 53.2 μg cm−2 : 0.25 U cm−2. UA was detected both optically as well as electrochemically. A redox electron shuttle, ferrocene carboxylic acid (FCA) was used to facilitate electron transfer. Entrapped UOx provided improved response to UA detection compared to physisorbed UOx. Sensor response was linear in the physiologically relevant ranges between 12 and 100 μM. The entrapped UOx biosensor was stable for 48 h and maintained 90 % activity until 5 days. This entrapped biosensor was used for UA measurements in biofluids of sweat and wounds. The sensor demonstrated a recovery of ∼102–107 %. These results show that entrapment of UA in such a polymer matrix is a preferred approach for UA measurements under physiological conditions.
Interest rate risk in long‐dated commodity options positions: To hedge or not to hedge?
Authors: Cheng Benjamin , Nikitopoulos Christina Sklibosios , Schlögl Erik
Published: July 2018

We empirically assess hedging interest rate risk beyond the conventional delta, gamma, and vega hedges in long‐dated crude oil options positions. Using factor hedging in a model featuring stochastic interest rates and stochastic volatility, interest rate hedges consistently provide an improvement beyond delta, gamma, and vega hedges. Under high interest rate volatility and/or when a rolling hedge is used, combining interest rate and delta hedging improves performance by up to four percentage points over the common hedges of gamma and/or vega. Thus, contrary to common practice, hedging interest rate risk should have priority over these “second‐order” hedges.
Mineral mapping using spaceborne Tiangong‐1 hyperspectral imagery and ASTER data: A case study of alteration detection in support of regional geological survey at Jintanzi‐Malianquan area, Beishan, Gansu Province, China
Authors: Liu Lei , Feng Jilu , Han Ling , Zhou Jun , Xu Xinliang , Liu Rui
Published: July 2018

This is an extension of our previous study and an applicability test on the mapping capability of Tiangong‐1 data with more complicated geological conditions over large areas. The Jintanzi‐Malianquan area is located in a major Au‐Cu‐Ni‐Cr resource belts in China. In order to support the 1:50,000 regional geological survey, this study presents the mapping results of using spectral angle mapper method and image endmembers from spaceborne Tiangong‐1 Hyperspectral Imager (HSI) shortwave infrared and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data. Six alteration minerals (muscovite, kaolinite, chlorite, epidote, calcite, and dolomite) related to hydrothermal ore deposits are used in the analysis. By comparing the results from both datasets, it is confirmed Tiangong‐1 HSI data can detect six major minerals (muscovite, kaolinite, chlorite, epidote, calcite, and dolomite), while ASTER can only discriminate the first five minerals in this study area. Fifteen targets for mineral exploration are mapped from the remote sensing results. Eleven targets have been verified by existing geologic maps and field validation for muscovite and epidote alteration. The results of this study suggest that the Tiangong‐1 HSI data are well suited for quick spaceborne reconnaissance of alteration minerals to support routine geological survey in large areas at 20‐m resolution, which provides continuous mapping products for all terrains at an accuracy of better than 1:50,000 scale map.
Astroglia contribute to the pathogenesis of spinocerebellar ataxia Type 1 (SCA1) in a biphasic, stage‐of‐disease specific manner
Authors: Kim Joo Hyun , Lukowicz Abigail , Qu Wenhui , Johnson Andrea , Cvetanovic Marija
Published: July 2018

Spinocerebellar ataxia type 1 (SCA1) is a fatal, dominantly inherited neurodegenerative disease caused by the expansion of CAG repeats in the Ataxin‐1 (ATXN1) gene. SCA1 is characterized by balance and coordination deficits due to the predominant loss of Purkinje neurons in the cerebellum. We previously demonstrated that cerebellar astrogliosis beings during the early stages of SCA1, prior to onset of motor deficits and loss of Purkinje neurons. We communicate here that cerebellar astrogliosis contributes to SCA1 pathogenesis in a biphasic, stage of disease dependent manner. We modulated astrogliosis by selectively reducing pro‐inflammatory transcriptional regulator nuclear factor κ‐light‐chain‐enhancer of activated B cells (NF‐κB) signaling in astroglia via a Cre‐lox mouse genetic approach. Our results indicate that inhibition of astroglial NF‐κB signaling, prior to motor deficit onset, exacerbates disease severity. This is suggestive of a neuroprotective role mediated by astroglia during early stage SCA1. In contrast, inhibition of astroglial NF‐κB signaling during late stage of disease ameliorated motor deficits, indicating a potentially harmful role of astroglia late in SCA1. These results indicate that astrogliosis may have a critical and dual role in disease. If so, our results imply that anti‐inflammatory astroglia‐based therapeutic approaches may need to consider disease progression to achieve therapeutic efficacy.
Incidence and severity of head injury hospitalisations in Australian children over a 10‐year period
Authors: Bierbaum Mia , Lystad Reidar P. , Curtis Kate , Mitchell Rebecca
Published: July 2018

Issue addressed

Child head injuries can cause life‐long disability and are a major cause of mortality globally. The incidence and impact of child head injuries in Australia is unknown. This study aimed to quantify the incidence, characteristics and treatment cost and to identify factors associated with the severity of hospitalisations of head injuries in Australian children.

Methods

Linked hospitalisation and mortality data were used to retrospectively examine hospitalisation trends for head injury in children aged ≤16 years and associated factors, in Australia, from 1 July 2002 to 30 June 2012.

Results

There were 164 126 hospitalisations of children for head injury during the 10‐year period, commonly male (65.5%), or aged ≤5 years (48.3%). The incidence among children aged <1 year and 1‐5 years significantly increased by 1.7% (95% CI 0.9‐2.6; P < 0.0001) and 1.5% (95% CI 1.1‐1.9; P < 0.0001) annually during the study period, respectively. The most common injury mechanisms across all age groups were falls (45.2%) and road trauma (16.0%). Head injury hospitalisations cost $468.9 million, with the higher costs found for children aged 11‐16 years, and for the most severe injuries.

Conclusion

Head injury hospitalisations cost the Australian health system close to half a billion dollars over a 10‐year period, with the most serious injuries resulting in lifelong health implications.

So what?

Targeted health promotion strategies such as the promotion of helmet wearing during scooter use, the introduction of cycleways, and impact absorbing surfaces on playgrounds, need to be implemented to reduce the occurrence of head injuries in children.
Prediction of Consumptive Use Under Different Soil Moisture Content and Soil Salinity Conditions Using Artificial Neural Network Models
Authors: Qi Yanbing , Huo Zailin , Feng Shaoyuan , Adeloye Adebayo J. , Dai Xiaoqin
Published: July 2018

The response of the water use of crops to soil moisture and salinity is complex to quantify using traditional field experiments. Based on field experimental data for 2 years, artificial neural network (ANN) models with five inputs including soil moisture content, total salt content, plant height, leaf area index and crop reference evapotranspiration (ET0) were developed to estimate daily actual evapotranspiration (ET). The models were later used to simulate the response of crop water consumption to soil moisture and salinity stresses at different growth stages. The results showed that the ANN model has a high precision with root mean squared error of 0.41 and 0.52 mm day‐1, relative error of 19.6 and 25.6%, and coefficient of determination of 0.87 and 0.79 for training and testing samples, respectively. Furthermore, the simulation results showed that the seed corn ET is sensitive to soil salt stress at all growth stages, although the salinity threshold at which the impact becomes felt and the extent of the impact vary for the different growth stages, with the booting and tasseling stages being the most robust. The study offers a more direct approach of evaluating actual crop evapotranspiration by considering explicitly water and salinity stresses. © 2018 John Wiley & Sons, Ltd.
Long‐noncoding RNA Atrolnc‐1 promotes muscle wasting in mice with chronic kidney disease
Authors: Sun Lijing , Si Meijun , Liu Xinyan , Choi Jong Min , Wang Yanlin , Thomas Sandhya S. , Peng Hui , Hu Zhaoyong
Published: July 2018

Background

Chronic kidney disease (CKD) is commonly associated with cachexia, a condition that causes skeletal muscle wasting and an unfavourable prognosis. Although mechanisms leading to cachexia have been intensively studied, the advance of biological knowledges and technologies encourages us to make progress in understanding the pathogenesis of this disorder. Long noncoding RNAs (lncRNAs) are defined as >200 nucleotides RNAs but lack the protein‐coding potential. LncRNAs are involved in the pathogenesis of many diseases, but whether they functionally involve in muscle protein loss has not been investigated.

Methods

We performed lncRNA array and identified an lncRNA, which we named Atrolnc‐1, remarkably elevated in atrophying muscles from mice with cachexia. We examined how overexpression or knockdown of Atrolnc‐1 could influence muscle protein synthesis and degradation. We also examined whether inhibition of Atrolnc‐1 ameliorates muscle wasting in mice with CKD.

Results

We documented that Atrolnc‐1 expression is continuously increased in muscles of mice with fasting (5.4 fold), cancer (2.0 fold), or CKD (5.1 fold). We found that depressed insulin signalling stimulates the transcription factor C/EBP‐α binding to the promoter of Atrolnc‐1 and promotes the expression of Atrolnc‐1. In cultured C2C12 myotubes, overexpression of Atrolnc‐1 increases protein degradation (0.45±0.03 vs. 0.64±0.02, *p<0.05); Atrolnc‐1 knockdown significantly reduces the rate of protein degradation stimulated by serum depletion (0.61±0.03 vs. 0.47±0.02, *p<0.05). Using mass spectrometry and a lncRNA pull‐down assay, we identified that Atrolnc‐1 interacts with A20 binding inhibitor of NF‐κB‐1 (ABIN‐1). The interaction impairs function, resulting in enhanced NF‐κB activity plus MuRF‐1 transcription. This response is counteracted by CRISPR/dCas9 mediated overexpression. In muscles from normal mice, overexpression of Atrolnc‐1 stimulates a 2.7‐fold increase in MuRF‐1 expression leading to myofibers atrophy. In contrast, Atrolnc‐1 knockdown attenuates muscle wasting by 42% in mice with CKD via suppression of NF‐κB activity and MuRF‐1 expression.

Conclusions

Our findings provide evidence that lncRNAs initiates the pathophysiological process of muscle wasting. The interaction between Atrolnc‐1 and NF‐κB signalling modulates muscle mass and proteolysis in CKD and perhaps other catabolic conditions.
Purkinje cell COX deficiency and mtDNA depletion in an animal model of spinocerebellar ataxia type 1
Authors: Ripolone Michela , Lucchini Valeria , Ronchi Dario , Fagiolari Gigliola , Bordoni Andreina , Fortunato Francesco , Mondello Stefania , Bonato Sara , Meregalli Mirella , Torrente Yvan , Corti Stefania , Comi Giacomo P. , Moggio Maurizio , Sciacco Monica
Published: July 2018

Spinocerebellar ataxias (SCAs) are a genetically heterogeneous group of cerebellar degenerative disorders, characterized by progressive gait unsteadiness, hand incoordination, and dysarthria. Ataxia type 1 (SCA1) is caused by the expansion of a CAG trinucleotide repeat in the SCA1 gene resulting in the atypical extension of a polyglutamine (polyQ) tract within the ataxin‐1 protein. Our main objective was to investigate the mitochondrial oxidative metabolism in the cerebellum of transgenic SCA1 mice. SCA1 transgenic mice develop clinical features in the early life stages (around 5 weeks of age) presenting pathological cerebellar signs with concomitant progressive Purkinje neuron atrophy and relatively little cell loss; this evidence suggests that the SCA1 phenotype is not the result of cell death per se, but a possible effect of cellular dysfunction that occurs before neuronal demise. We studied the mitochondrial oxidative metabolism in cerebellar cells from both homozygous and heterozygous transgenic SCA1 mice, aged 2 and 6 months. Histochemical examination showed a cytochrome‐c‐oxidase (COX) deficiency in the Purkinje cells (PCs) of both heterozygous and homozygous mice, the oxidative defect being more prominent in older mice, in which the percentage of COX‐deficient PC was up to 30%. Using a laser‐microdissector, we evaluated the mitochondrial DNA (mtDNA) content on selectively isolated COX‐competent and COX‐deficient PC by quantitative Polymerase Chain Reaction and we found mtDNA depletion in those with oxidative dysfunction. In conclusion, the selective oxidative metabolism defect observed in neuronal PC expressing mutant ataxin occurs as early as 8 weeks of age thus representing an early step in the PC degeneration process in SCA1 disease.
Brain structural changes associated with aberrant functional responses to the Valsalva maneuver in heart failure
Authors: Song Xiaopeng , Roy Bhaswati , Fonarow Gregg C. , Woo Mary A. , Kumar Rajesh
Published: July 2018

Heart failure (HF) patients show inability to regulate autonomic functions in response to autonomic challenges. The autonomic deficits may stem from brain tissue injury in central autonomic regulatory areas, resulting from ischemic and hypoxic processes accompanying the condition. However, the direct evaluation of correlations between brain structural injury and functional timing and magnitude of neural signal patterns within affected areas, which may lead to impaired autonomic outflow, is unclear. In this study, we evaluate neural responses to the Valsalva maneuver with blood oxygen level‐dependent functional magnetic resonance imaging in 29 HF patients and 35 control subjects and brain structural changes using diffusion tensor imaging‐based mean diffusivity in a subsample of 19 HF and 24 control subjects. HF showed decreased neural activation in multiple autonomic and motor control areas, including cerebellum cortices, vermis, left insular, left putamen, and bilateral postcentral gyrus. Structural brain changes emerged in similar autonomic, as well as cognitive and mood regulation areas. Functional MRI responses in cerebellum and insula in HF subjects are delayed or decreased in magnitude to the challenge. The impaired functional responses of insular and cerebellar sites are correlated with the severity of tissue changes. These results indicate that the functions of insular and cerebellar regions, sites that are involved in autonomic regulation, are compromised, and that autonomic deficits in these areas have brain structural basis for impaired functions. Our study enhanced our understanding of brain structural and functional alterations underlying impaired autonomic regulations in HF subjects.
The role of 5‐hydroxymethylcytosine in mitochondria after ischemic stroke
Authors: Ji Feng , Zhao Chenyu , Wang Bin , Tang Yan , Miao Zhigang , Wang Yongxiang
Published: July 2018

5‐Hydroxymethylcytosine (5hmC) exists in DNA, RNA, and mitochondrial DNA (mtDNA) and plays an important role in many diseases. Specifically, 5hmC is involved in promoting gene expression, and this process is regulated by Tet enzymes. In this study, we identified that there is no difference in male mice and female mice at first; then we examined the levels of 5hmC in mtDNA and explored the relationship among 5hmC, mitochondrial gene expression and ATP production after acute brain ischemia. The abundance of mtDNA 5hmC was increased at 1 d and peaked at 2 d after ischemic injury, whereas that of mtDNA 5mC was unchanged. Furthermore, increased mitochondrial Tet2 expression was found to be responsible for the increase in mtDNA 5hmC. Tet2 inhibition decreased the mtDNA 5hmC abundance and increased the ATP levels in mitochondria, suggesting an association between the cellular ATP levels and mtDNA 5hmC abundance. We also demonstrated that mtDNA 5hmC increased the mRNA levels of mitochondrial genes after ischemia/reperfusion (I/R) injury.
Shift of daily rainfall peaks over the Beijing–Tianjin–Hebei region: An indication of pollutant effects?
Authors: Zhou Siyuan , Yang Jing , Wang Wei‐Chyung , Gong Daoyi , Shi Peijun , Gao Miaoni
Published: July 2018

Aerosol impacts on diurnal variations of rainfall over the Beijing–Tianjin–Hebei region are investigated by comparing the observations between polluted and clean days in early summer (June 1 to July 20) before the rainy season begins. The 2002–2012 hourly rainfall measurements in conjunction with environmental data reveal that during high‐pollution days the peak of heavy rainfall shifted ~4 hr earlier while the peak of light rainfall delayed by 2–3 hr. Detailed analyses of meteorological conditions associated with the shifts suggest that the former is mainly caused by enhanced lower‐level aerosol heating during the daytime which increases the lower‐troposphere instability and facilitates the convective rainfall occurrence, and the latter is related to decreases of conversion of cloud droplets into raindrops associated with aerosol increases. Nevertheless, conducting model sensitivity simulations to better understand aerosol–cloud microphysics–precipitation interactions is warranted.