bluuebunny/crossref_metadata_2025 huggingface dataset:
Neural correlates of intertemporal choice in aggressive behavior
Authors: Chester David S. , Bell Sarah Beth , DeWall C. Nathan , West Samuel J. , Romero‐Lopez Marisabel , Craig Adam W.
Published: April 2019

People often have to make decisions between immediate rewards and more long‐term goals. Such intertemporal judgments are often investigated in the context of monetary choice or drug use, yet not in regard to aggressive behavior. We combined a novel intertemporal aggression paradigm with functional neuroimaging to examine the role of temporal delay in aggressive behavior and the neural correlates thereof. Sixty‐one participants (aged 18–22 years; 37 females) exhibited substantial variability in the extent to which they selected immediate acts of lesser aggression versus delayed acts of greater aggression against a same‐sex opponent. Choosing delayed‐yet‐more‐severe aggression was increased by provocation and associated with greater self‐control. Preferences for delayed aggression were associated with greater activity in the ventromedial prefrontal cortex (VMPFC) during such choices, and reduced functional connectivity between the VMPFC and brain regions implicated in motor impulsivity. Preferences for immediate aggression were associated with reduced functional connectivity between the VMPFC and the frontoparietal control network. Dispositionally aggressive participants exhibited reduced VMPFC activity, which partially explained and suppressed their preferences for delayed aggression. Blunted VMPFC activity may thus be a neural mechanism that promotes reactive aggression towards provocateurs among dispositionally aggressive individuals. These findings demonstrate the utility of an intertemporal framework for investigating aggression and provide further evidence for the similar underlying neurobiology between aggression and other rewarding behaviors.
Understanding the past: Investigating the role of availability, outcome, and hindsight bias and close calls in visual pilots' weather‐related decision making
Authors: Walmsley Stephen , Gilbey Andrew
Published: April 2019

Past events, such as “close calls,” can provide valuable learning opportunities, especially in aviation, where learning from past errors could potentially help to avoid future incidents or accidents. This study investigated whether three cognitive biases (availability, outcome, and hindsight bias) could influence pilots' perceptions of past events, which in turn might influence their perception of events yet to occur. Study 1 found that pilots were influenced by the outcome of a flight when judging decision quality. Of particular interest was that pilots interpreted events that led to a close call very similarly to those that had positive outcomes, which may reinforce risky behaviour. However, although adequately powered, Study 1 found no evidence of availability bias: Exposure to one of four outcomes did not appear to influence later decisions. Study 2 found that having read a flight report, particularly if it ended in a crash, pilots consistently overestimated their likelihood of predicting the actual outcome, which may reduce any opportunity to learn. These findings suggest that two of the three cognitive biases explored in this study could influence a pilot's perception of past events in ways that may adversely affect how they make future decisions that in turn may affect flight safety.
Konzertierte nukleophile aromatische Substitutionen
Authors: Rohrbach Simon , Smith Andrew J. , Pang Jia Hao , Poole Darren L. , Tuttle Tell , Chiba Shunsuke , Murphy John A.
Published: April 2019

Jüngste Entwicklungen in der experimentellen und theoretischen Chemie haben zur Identifizierung einer schnell wachsenden Klasse von nukleophilen aromatischen Substitutionsreaktionen geführt, die einem konzertierten Mechanismus (cSNAr) folgen, und nicht dem klassischen, zweistufigen SNAr‐Mechanismus. Während klassische SNAr‐Reaktionen auf die substantielle Aktivierung des aromatischen Ringes durch elektronenziehende Substituenten angewiesen sind, ist eine solche Aktivierung für den konzertierten Reaktionsverlauf nicht zwingend nötig.
Iridium‐Catalyzed Distal Hydroboration of Aliphatic Internal Alkenes
Authors: Wang Guangzhu , Liang Xinyi , Chen Lili , Gao Qian , Wang Jian‐Guo , Zhang Panke , Peng Qian , Xu Senmiao
Published: April 2019

The regioselective hydroboration of aliphatic internal alkenes remains a great challenge. Reported herein is an iridium‐catalyzed hydroboration of aliphatic internal alkenes, providing distal‐borylated products in good to excellent yields with high regioselectivity (up to 99:1). We also demonstrate that the C−B bond of the distal‐borylated product can be readily converted into other functional groups. DFT calculations indicate that the reaction proceeds through an unexpected IrIII/IrV cycle.
Charge Transport through Self‐Assembled Monolayers of Monoterpenoids
Authors: Cafferty Brian J. , Yuan Li , Baghbanzadeh Mostafa , Rappoport Dmitrij , Beyzavi M. Hassan , Whitesides George M.
Published: April 2019

The nature of the processes at the origin of life that selected specific classes of molecules for broad incorporation into cells is controversial. Among those classes selected were polyisoprenoids and their derivatives. This paper tests the hypothesis that polyisoprenoids were early contributors to membranes in part because they (or their derivatives) could facilitate charge transport by quantum tunneling. It measures charge transport across self‐assembled monolayers (SAMs) of carboxyl‐terminated monoterpenoids (O2C(C9HX)) and alkanoates (O2C(C7HX)) with different degrees of unsaturation, supported on silver (AgTS) bottom electrodes, with Ga2O3/EGaIn top electrodes. Measurements of current density of SAMs of linear length‐matched hydrocarbons—both saturated and unsaturated—show that completely unsaturated molecules transport charge faster than those that are completely saturated by approximately a factor of ten. This increase in relative rates of charge transport correlates with the number of carbon–carbon double bonds, but not with the extent of conjugation. These results suggest that polyisoprenoids—even fully unsaturated—are not sufficiently good tunneling conductors for their conductivity to have favored them as building blocks in the prebiotic world.
Recent Advances on Electrochemical Biosensing Strategies toward Universal Point‐of‐Care Systems
Authors: Dai Yifan , Liu Chung Chiun
Published: April 2019

A number of very recently developed electrochemical biosensing strategies are promoting electrochemical biosensing systems into practical point‐of‐care applications. The focus of research endeavors has transferred from detection of a specific analyte to the development of general biosensing strategies that can be applied for a single category of analytes, such as nucleic acids, proteins, and cells. In this Minireview, recent cutting‐edge research on electrochemical biosensing strategies are described. These developments resolved critical challenges regarding the application of electrochemical biosensors to practical point‐of‐care systems, such as rapid readout, simple biosensor fabrication method, ultra‐high detection sensitivity, direct analysis in a complex biological matrix, and multiplexed target analysis. This Minireview provides general guidelines both for scientists in the biosensing research community and for the biosensor industry on development of point‐of‐care system, benefiting global healthcare.
Concerted Nucleophilic Aromatic Substitution Reactions
Authors: Rohrbach Simon , Smith Andrew J. , Pang Jia Hao , Poole Darren L. , Tuttle Tell , Chiba Shunsuke , Murphy John A.
Published: April 2019

Recent developments in experimental and computational chemistry have identified a rapidly growing class of nucleophilic aromatic substitutions that proceed by concerted (cSNAr) rather than classical, two‐step, SNAr mechanisms. Whereas traditional SNAr reactions require substantial activation of the aromatic ring by electron‐withdrawing substituents, such activating groups are not mandatory in the concerted pathways.
Unidirectional Presentation of Membrane Proteins in Nanoparticle‐Supported Liposomes
Authors: Chen Wen , Cai Yongfei , Fu Qingshan , Chen Bing , Guo Junling , Chou James J.
Published: April 2019

Presentation of membrane proteins to host immune systems has been a challenging problem owing to complexity arising from the poor in vivo stability of the membrane‐mimetic media often used for solubilizing the membrane proteins. The use of functionalized, biocompatible nanoparticles as substrates is shown to guide the formation of proteoliposomes, which can present many copies of membrane proteins in a unidirectional manner. The approach was demonstrated to present the membrane‐proximal region of the HIV‐1 envelope glycoprotein. These nanoparticle‐supported liposomes are broadly applicable as membrane antigen vehicles for inducing host immune responses.
Magnetic nanoporous MCM‐41 supported ionic liquid/palladium complex: An efficient nanocatalyst with high recoverability
Authors: Abaeezadeh Somayeh , Elhamifar Dawood , Norouzi Meysam , Shaker Masoumeh
Published: April 2019

In this study, a novel magnetic mesoporous MCM‐41 silica supported ionic liquid/palladium complex (Fe3O4@MCM@IL/Pd) with core‐structure was prepared and characterized and its catalytic performance was developed under green conditions. The Fe3O4@MCM@IL/Pd was prepared via a post grafting method and was characterized using Fourier transform infrared spectroscopy, thermal gravimetric analysis, wide‐ and low‐angle powder X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, vibration sample magnetometer and energy‐dispersive X‐ray analyses. This was applied as an efficient and recoverable nanocatalyst for the one‐pot synthesis of pyrano[2,3‐d]pyrimidine derivatives under ultrasonic conditions. The catalyst was magnetically recovered and reused for 12 consecutive cycles without significant loss of its activity and selectivity.
Data objects and documenting scientific processes: An analysis of data events in biodiversity data papers
Authors: Li Kai , Greenberg Jane , Dunic Jillian
Published: April 2019

The data paper, an emerging scholarly genre, describes research data sets and is intended to bridge the gap between the publication of research data and scientific articles. Research examining how data papers report data events, such as data transactions and manipulations, is limited. The research reported on in this article addresses this limitation and investigated how data events are inscribed in data papers. A content analysis was conducted examining the full texts of 82 data papers, drawn from the curated list of data papers connected to the Global Biodiversity Information Facility. Data events recorded for each paper were organized into a set of 17 categories. Many of these categories are described together in the same sentence, which indicates the messiness of data events in the laboratory space. The findings challenge the degrees to which data papers are a distinct genre compared to research articles and they describe data‐centric research processes in a through way. This article also discusses how our results could inform a better data publication ecosystem in the future.
Design and Fabrication of Tubular Micro/Nanomotors via 3D Laser Lithography
Authors: Chen Yimeng , Xu Borui , Mei Yongfeng
Published: April 2019

Catalytic tubular micro/nanomachines convert chemical energy from a surrounding aqueous fuel solution into mechanical energy to generate autonomous movements, propelled by the oxygen bubbles decomposed by hydrogen peroxide and expelled from the microtubular cavity. With the development of nanotechnology, micro/nanomotors have attracted more and more interest due to their numerous potential for in vivo and in vitro applications. Here, highly efficient chemical catalytic microtubular motors were fabricated via 3D laser lithography and their motion behavior under the action of driving force in fluids was demonstrated. The frequency of catalytically‐generated bubbles ejection was influenced by the geometrical shape of the micro/nanomotor and surrounding chemical fuel environment, resulting in the variation in motion speed. The micro/nanomotors generated with a rocket‐like shape displayed a more active motion compared with that of a single tubular micro/nanomotor, providing a wider range of practical micro‐/nanoscale applications in the future.
Identification of nacre matrix protein genes hic14 and hic19 and their roles in crystal growth and pearl formation in the mussel Hyriopsis cumingii
Authors: Jin Can , Ren Hong‐Yu , Pu Jing‐Wen , Liu Xiao‐Jun , Li Jia‐Le
Published: April 2019

Biological mineralization is a highly programmed process in which inorganic minerals reassociate under the strict control of the extracellular matrix to form minerals with special functions and patterns. Shells are biominerals, and their synthesis is finely regulated by organic matrix including matrix proteins, polysaccharides, lipids, pigments, free amino acids, and small peptides. In this study, two matrix protein genes, hic14 and hic19, were isolated from the mantle of the mussel Hyriopsis cumingii. Tissue expression analysis showed that both proteins were expressed mainly in the mantle, and in situ hybridization of mantle tissues showed that they were specifically expressed in the dorsal epithelial cells of mantle pallial. Therefore, hic14 and hic19 were both nacreous layer matrix proteins. In the pearl insertion experiment, hic14 and hic19 kept low expression during pearl sac formation and disordered calcium carbonate deposition, and increased significantly during pearl nacre accumulation, which showed that both proteins participated in the mineralization of pearl nacre. In the RNA interference experiment, shell nacre tablet growth was inhibited after crystal nucleation due to the decreased expression of hic14, and crystal morphology and arrangement of nacre were highly modified after expression of hic19 was inhibited. These results provided further evidence that both hic14 and hic19 participated in nacreous layer biomineralization.
Veränderung der mechanischen Kenngrößen von Betonstabstählen durch chloridinduzierte Korrosion
Authors: Baumgartner Alexander , Fraundorfer Andreas , Dauberschmidt Christoph , Kustermann Andrea
Published: April 2019

Die Dauerhaftigkeit chloridexponierter Stahlbetonbauteile wird maßgeblich durch das Korrosionsverhalten des Bewehrungsstahls bestimmt. Hat ein Eintrag von Chloriden in kritischer Konzentration in das Bauteil stattgefunden, kann eine Lochfraßkorrosion initiiert werden. Die durch die Korrosion auftretenden, sehr lokalen Materialabträge können in kurzer Zeit zu hohen Querschnittsverlusten der Bewehrung führen.

Für die Instandsetzungsplanung steht der/die Sachkundige PlanerIn vor der Aufgabe, Art und Umfang der Instandsetzungsmaßnahme festzulegen. Dabei stellt sich auch die Herausforderung, vorhandene Querschnittsverluste zielsicher beurteilen zu können. Eine exakte Bestimmung des Querschnittsverlusts auf der Baustelle ist jedoch aufgrund der Narbengeometrie nur schwer möglich, weshalb Querschnittsverluste häufig visuell abgeschätzt werden. Auch stellt sich die Frage, ob durch Lochfraßnarben Kerbspannungen verursacht werden, die einen Einfluss auf die Zugtragfähigkeit haben und zu abweichenden Festigkeitswerten im Vergleich zur reinen Querschnittsbetrachtung führen. Weiterhin zu hinterfragen ist der Einfluss der lokalen Schädigung auf das Dehnungsverhalten des Bewehrungsstahls und damit auf eine duktile Versagensankündigung des Bauteils.

Zur besseren Beurteilbarkeit lochfraßgeschädigter Bewehrung wurden an der Hochschule München Versuche an Betonstählen mit einem weiten Schädigungsspektrum infolge chloridinduzierter Korrosion durchgeführt. Hierzu wurden natürlich geschädigte Betonstabstähle verschiedenen Durchmessers aus einer Tiefgarage der 1960er Jahre entnommen und im Labor künstlich geschädigte Proben hergestellt. Die Stahlproben wurden auf ihr optisches Erscheinungsbild, den Restquerschnitt sowie das Dehnungsverhalten und die statische Restzugtragfähigkeit hin untersucht.
A comparison of prompting methods to teach sight words to students with autism spectrum disorder
Authors: Klaus Sophie , Hixson Michael D. , Drevon Daniel D. , Nutkins Christie
Published: April 2019

Time delay procedures are one of the most commonly used and effective strategies for teaching sight words to learners with disabilities. However, less is known about whether they are differentially effective and efficient with learners. This study compared the effectiveness and efficiency of progressive time delay and simultaneous prompting on sight word acquisition among three learners with autism spectrum disorder using an adapted alternating treatments design across word sets. For two participants, both procedures led to skill acquisition with no clear differences in efficiency. For the remaining participant, neither procedure was effective; therefore, the reading task was changed to a receptive one, and a stimulus fading intervention package was implemented.
Quantitative analysis of multicomponents by a single marker and quality evaluation of Venenum Bufonis from different geographical origins
Authors: Cui Ke‐ke , Cao Yue‐ting , Shao Jia‐feng , Lu Zheng‐yu , Wang Long‐hu
Published: April 2019

Bufadienolides are the main bioactive components of Venenum Bufonis (VB) and have been widely used to treat different types of human cancers for decades. The bufadienolide content in VB varies significantly in materials from different geographical origins. In this work, a new strategy for the quality assessment of VB was developed through quantitative analysis of multi‐components by single marker (QAMS). Cinobufagin was selected as the internal reference substance; seven bufadienolides were separated and simultaneously determined based on relative correction factors. The correlation coefficient value (r ≥ 0.9936) between QAMS and the normal external standard method proved the consistency of the two methods. According to the outcomes of 30 batches of VB samples, the contents of the seven bufadienolides were used for further chemometric analysis. All of the samples of VB from various geographical origins were divided into three categories based on hierarchical cluster analysis and radar plot, which indicated the crucial influence of geographical origins on VB. This study showed that QAMS combined with chemometristry could be used to comprehensively evaluate and effectively control the quality of VB from different geographical origins.
Probing Local Folding Allows Robust Metal Sensing Based on a Na+‐Specific DNAzyme
Authors: He Yanping , Chang Yangyang , Chen Da , Liu Juewen
Published: April 2019

Fluorescent metal sensors based on DNA often rely on changes in end‐to‐end distance or local environmental near fluorophore labels. Because metal ions can also nonspecifically interact with DNA through various mechanisms, such as charge screening, base binding, and increase or decrease in duplex stability, robust and specific sensing of metal ions has been quite challenging. In this work, a side‐by‐side comparison of two signaling strategies on a Na+‐specific DNAzyme that contained a Na+‐binding aptamer was performed. The duplex regions of the DNAzyme was systematically shortened and its effect was studied by using a 2‐aminopurine (2AP)‐labeled substrate strand. Na+ binding affected the local environmental of the 2AP label and increased its fluorescence. A synergistic process of Na+ binding and forming the duplex on the 5′‐end of the enzyme strand was observed, and this end was close to the aptamer loop. Effective Na+ binding was achieved with a five base‐pair stem. The effect on the 3′‐end is more continuous, and the stem needs to form first before Na+ can bind. With an optimized substrate binding arm, a FRET‐based sensor has been designed by labeling the two ends of a cis form of the DNAzyme with two fluorophores. In this case, Na+ failed to show a distinct difference from that of Li+ or K+; thus indicating that probing changes to the local environment allows more robust sensing of metal ions.
Hierarchical High‐Porosity Graphene Oxide‐Porous Carbon/Sulfur Composite with Sodium Chloride as Temporary Space Holders for High‐Performance Lithium‐Sulfur Batteries
Authors: Chen Xingbu , Wang Yang , Wang Yichen , Huang Jingyun , Ye Zhizhen
Published: April 2019

The ultrahigh theoretical specific capacity and energy density of lithium‐sulfur batteries have attracted extensive research, but the main issues including the insulating nature of sulfur, large volumetric expansion during discharging, and shuttle effect of polysulfides still need to be solved. Herein, a hierarchical high‐porosity graphene oxide‐porous carbon/sulfur (GO‐PC/S) composite cathode is designed and fabricated. In this work, sodium chloride was used as temporary space holders to create a hierarchical porous structure for accelerating the transmission of Li+, accommodating the volumetric expansion, and enlarging the specific surface area (342.623 m2 g−1) up to eight times. Owing to the abundant oxygen‐containing functional groups of GO, sulfur and polysulfides can be effectively immobilized and the conductivity is enhanced by porous carbon. The Li−S battery exhibits outstanding kinetic performance and rate capability (618.3 mAh g−1 at 2 C) as well as excellent cycling performance over 300 cycles.
Few‐Layer Boron Nitride with Engineered Nitrogen Vacancies for Promoting Conversion of Polysulfide as a Cathode Matrix for Lithium–Sulfur Batteries
Authors: Yi Yikun , Li Hongping , Chang Honghong , Yang Pu , Tian Xiaolu , Liu Pei , Qu Long , Li Mingtao , Yang Bolun , Li Huaming , Zhu Wenshuai , Dai Sheng
Published: April 2019

Lithium–sulfur (Li‐S) batteries have become one of the most promising candidates as next‐generation batteries, owing to their high specific capacity, low cost, and environmental benignity. Although many strategies have been proposed to restrain the shuttle of lithium polysulfides (LiPSs) through physical trapping and chemical binding, the sluggish kinetics of PS conversion still degrade the capacity, rate, and cycling performance of Li‐S batteries. Herein, a novel kind of few‐layer BN with engineered nitrogen vacancies (v‐BN) has been developed as a cathode matrix for Li‐S batteries. The positive vacancies in the BN nanosheets not only promote the immobilization and conversion of LiPSs, but also accelerate the lithium ion diffusion in cathode electrodes. Compared with pristine BN, the v‐BN cathodes exhibit higher initial capacities from 775 mA h g−1 to 1262 mA h g−1 at 0.1 C and a high average coulombic efficiency of over 98 % during 150 cycles. Upon increasing the current density to 1 C, the cell still preserves a capacity of 406 mA h g−1 after 500 cycles, exhibiting a capacity decay of only 0.084 % per cycle. The new vacancy‐engineered material provides a promising method for achieving excellent performance in Li‐S batteries.
Alkylative Carboxylation of Ynamides and Allenamides with Functionalized Alkylzinc Halides and Carbon Dioxide by a Copper Catalyst
Authors: Takimoto Masanori , Gholap Sandeep Suryabhan , Hou Zhaomin
Published: April 2019

The alkylative carboxylation of ynamides and allenamides with CO2 and alkylzinc halides catalyzed by a copper catalyst was developed. A variety of alkylzinc halides bearing functional groups were used for this transformation to afford α,β‐unsaturated carboxylic acids, which contain the α,β‐dehydroamino acid skeleton, introducing the corresponding alkyl group and CO2 across the carbon–carbon triple or double bond. This alkylative carboxylation formally consists of Cu‐catalyzed carbozincation of ynamides or allenamides with alkylzinc halides and the subsequent nucleophilic carboxylation of the resulting alkenylzinc species with CO2. This protocol would be a useful method for the synthesis of α,β‐dehydroamino acid derivatives possessing a functionalized alkyl group due to the high regio‐ and stereoselectivity, simple one‐pot procedure as well as the use of CO2 as a starting material.
Benchmarking Three Ruthenium Phosphide Phases for Electrocatalysis of the Hydrogen Evolution Reaction: Experimental and Theoretical Insights
Authors: Liu Tingting , Wang Jianmei , Zhong Changyin , Lu Shiyu , Yang Wenrong , Liu Jian , Hu Weihua , Li Chang Ming
Published: April 2019

The outstanding electrocatalytic activity of ruthenium (Ru) phosphides toward the hydrogen evolution reaction (HER) has received wide attention. However, the effect of the Ru phosphide phase on the HER performance remains unclear. Herein, a two‐step method was developed to synthesize nanoparticles of three types of Ru phosphides, namely, Ru2P, RuP, and RuP2, with similar morphology, dimensions, loading density, and electrochemical surface area on graphene nanosheets by simply controlling the dosage of phytic acid as P source. Electrochemical tests revealed that Ru2P/graphene shows the highest intrinsic HER activity, followed by RuP/graphene and RuP2/graphene. Ru2P/graphene affords a current density of 10 mA cm−2 at an overpotential of 18 mV in acid media. Theoretical calculations further showed that P‐deficient Ru2P has a lower free energy of hydrogen adsorption on the surface than other two, P‐rich Ru phosphides (RuP, RuP2), which confirms the excellent intrinsic HER activity of Ru2P and is consistent with experiment results. The work reveals for the first time a clear trend of HER activity among three Ru phosphide phases.
Covalently Linked Bis(Amido‐Corroles): Inter‐ and Intramolecular Hydrogen‐Bond‐Driven Supramolecular Assembly
Authors: Orłowski Rafał , Cichowicz Grzegorz , Staszewska‐Krajewska Olga , Schilf Wojciech , Cyrański Michał K. , Gryko Daniel T.
Published: April 2019

Four bis‐corroles linked by diamide bridges were synthesized through peptide‐type coupling of a trans‐A2B‐corrole acid with aliphatic and aromatic diamines. In the solid state, the hydrogen‐bond pattern in these bis‐corroles is strongly affected by the type of solvent used in the crystallization process. Although intramolecular hydrogen bonds play a decisive role, they are supported by intermolecular hydrogen bonds and weak N−H⋅⋅⋅π interactions between molecules of toluene and the corrole cores. In an analogy to mono(amido‐corroles), both in crystalline state and in solutions, the aliphatic or aromatic bridge is located directly above the corrole ring. When either ethylenediamine or 2,3‐diaminonaphthalene are used as linkers, incorporation of polar solvents into the crystalline lattice causes a roughly parallel orientation of the corrole rings. At the same time, both NHCO⋅⋅⋅NH corrole hydrogen bonds are intramolecular. In contrast, solvation in toluene causes a distortion with one of the hydrogen bonds being intermolecular. Interestingly, intramolecular hydrogen bonds are always formed between the –NHCO– functionality located further from the benzene ring present at the position 10‐meso. In solution, the hydrogen‐bonds pattern of the bis(amido‐corroles) is strongly affected by the type of the solvent. Compared with toluene (strongly high‐field shifted signals), DMSO and pyridine disrupt self‐assembly, whereas hexafluoroisopropanol strengthens intramolecular hydrogen bonds.
Interaction between Spirosilanes and Lewis Bases: from Coordination to Frustration
Authors: Medici Fabrizio , Maury Julien , Lemière Gilles , Fensterbank Louis
Published: April 2019

In this work, the interaction between Lewis bases, especially N‐heterocyclic carbenes (NHCs), and hindered neutral silicon derivatives featuring high Lewis acidity is described. The formation of normal and abnormal Lewis adducts could be controlled by varying the acidity of the corresponding tetravalent spiro organosilane. Some DFT calculations permitted to gain insight into the thermodynamics of the NHC–spirosilane interaction featuring various NHCs differing in size and σ‐donor capacity. Spirosilanes are introduced as new Lewis partners in frustrated Lewis pair (FLP) chemistry and some FLP‐type reactivities are presented, in particular the activation of formaldehyde that could occur with both hindered NHCs and phosphines.
A non‐intrusive Smart metering system: Analytics and simulation of power consumption
Authors: Fecil'ak Peter , Pekár Adrián , Ádám Norbert , Baláž Anton , Chovancová Eva
Published: April 2019

This contribution deals with the design and experimental implementation of a Smart Metering Architecture which supports different transport technologies, ie, Ethernet, WiFi, and LoRa. Appropriate methods for measuring electrical quantities have been analysed, which resulted in a couple of prototypes. The contribution describes the design and implementation of two versions of measuring devices, which were used for the purpose of experimental implementation. The test results have shown that the latest version of the measuring device based on a Teridian on‐chip metering system is more precise in terms of measuring accuracy. The presented paper shares the results of the data analytics based on NIALM algorithm and power profile disaggregation in a test environment. Simulation tool, which helps us to predict the power consumption of the defined location based on realistic behaviour and in combination with realistic data from the developed Smart metering prototypes, has been also documented in this research paper.
Aseptic Technique
Authors: Bykowski Tomasz , Holt Jonathan F. , Stevenson Brian
Published: April 2019

This article describes common laboratory procedures that can reduce the risk of culture contamination, collectively referred as “aseptic technique.” Two major strategies of aseptic work are described: using a Bunsen burner and a biosafety cabinet. Both methods are presented in the form of general protocols applicable to a variety of laboratory tasks such as pipetting and aliquotting, preparation of growth media, inoculation, passaging, and spreading microorganisms on petri dishes. © 2019 by John Wiley & Sons, Inc.
Enantiospecific Pharmacogenomics of Fluvastatin
Authors: Hirvensalo Päivi , Tornio Aleksi , Neuvonen Mikko , Kiander Wilma , Kidron Heidi , Paile‐Hyvärinen Maria , Tapaninen Tuija , Backman Janne T. , Niemi Mikko
Published: April 2019

The aim of this study was to investigate how variability in multiple genes related to pharmacokinetics affects fluvastatin exposure. We determined fluvastatin enantiomer pharmacokinetics and sequenced 379 pharmacokinetic genes in 200 healthy volunteers. CYP2C9*3 associated with significantly increased area under the plasma concentration‐time curve (AUC) of both 3R,5S‐fluvastatin and 3S,5R‐fluvastatin (by 67% and 94% per variant allele copy, P = 3.77 × 10−9 and P = 3.19 × 10−12). In contrast, SLCO1B1 c.521T>C associated with increased AUC of active 3R,5S‐fluvastatin only (by 34% per variant allele copy; P = 8.15 × 10−8). A candidate gene analysis suggested that CYP2C9*2 also affects the AUC of both fluvastatin enantiomers and that SLCO2B1 single‐nucleotide variations may affect the AUC of 3S,5R‐fluvastatin. Thus, SLCO transporters have enantiospecific effects on fluvastatin pharmacokinetics in humans. Genotyping of both CYP2C9 and SLCO1B1 may be useful in predicting fluvastatin efficacy and myotoxicity.
Dentists' decisions regarding the need for cuspal coverage for endodontically treated and vital posterior teeth
Authors: Abu‐Awwad Motasum
Published: April 2019

Objectives

Deciding when cuspal coverage is needed for posterior teeth is considered a challenge for dentists. The aims were to assess dentists' decision making regarding the need for cuspal coverage for vital teeth (VT) and endodontically treated teeth (ETT) with varying amounts of tooth structure loss and to identify clinical situations of dissimilarity and uncertainty in decision making.

Materials and Methods

A random sample of 182 dentists were invited to participate in the survey. The survey included photos of 13 posterior teeth: six VT and seven ETT. The clinical situations selected were based on a hypothetical scale of typodont teeth with ascending amounts of tooth structure loss. A brief description of each situation was provided. Each dentist was asked to decide whether cuspal coverage is needed, not needed, or unsure. Descriptive analyses using SPSS were conducted. Seventy‐five percent was chosen as a cutoff point for assessing similarity in decision making. The unsure answer reflected uncertainty. Associations were assessed using chi‐square test.

Results

One hundred twenty dentists participated (65.9% response rate, 70 females). Median for years of experience was 3.5 (interquartile range 1.1–10.8). Analyses revealed a similarity percentage of <75% in decision making among dentists for six clinical situations: four VT and two ETT. More similarity was observed for situations at both ends of the scale with minimal and severe amounts of tooth structure loss and more for ETT than for VT. The highest percentages of uncertainty were more for VT than for ETT. Clinical conditions of VT were more likely to receive the “not sure” decision compared with those of ETT (χ2, P < .001). No association was detected with gender (χ2, P = .509) or years of experience (χ2, P = .223).

Conclusions

Dissimilarity and uncertainty in deciding when cuspal coverage is needed were observed especially for VT and teeth with a moderate amount of structure loss.
Facial skin blood perfusion change based liveness detection using video images
Authors: Ukai Kazutoshi , Rahman Rashedur , Kobashi Syoji
Published: April 2019

Facial recognition has been employed as a user‐friendly person authentication method, and facial spoofing attack has become a common problem. Although there are two kinds of facial spoofing attacks, 2D spoofing and 3D spoofing, almost studies evaluate the performance only for 2D spoofing. Temporal change of face color will be a possible characteristic to detect liveness against to 3D spoofing attack because there is a relationship between the skin blood perfusion change and the temporal color change in facial video images. This paper proposes two features, R‐G correlation feature and interarea correlation feature, to detect liveness using video images. Also, liveness detection method using support vector machine is demonstrated. The performance was evaluated by accuracy (ACC) for classifying liveness face and three types of spoofing face—2D printed image, 2D monitor image, and 3D doll. The ACC was 99.2% at the lighting condition of room light, 99.5% at sunlight illuminating the face, and 98.6% at sunlight illuminating the back of the head.
Simulating the effects of climate variability on waterbodies and wetland‐dependent birds in the Prairie Pothole Region
Authors: McIntyre N. E. , Liu G. , Gorzo J. , Wright C. K. , Guntenspergen G. R. , Schwartz F.
Published: April 2019

Understanding how bird populations respond to changes in waterbody availability in the climatically variable Prairie Pothole Region (PPR) of North America hinges on being able to couple hydrological and climate modeling to represent potential future landscapes. Model experiments run with the Pothole Complex Hydrologic Model using downscaled climate data (variables relating to precipitation, temperature, and potential evapotranspiration at 1/8° spatial resolution under four general circulation climate models and two gas emissions scenarios) were used to forecast the abundances of six focal wetland‐dependent bird species in the Missouri Coteau portion of the PPR, providing ensemble scenarios at a spatial scale relevant to resource management. Although the projected number of May ponds (waterbodies present during bird breeding season) fluctuated through time with some decadal periodicity (and with the number present in a given year reflecting abundance over the previous three years), the ensemble model average indicated an increase in the average number of waterbodies present by the turn of the next century. Overall, the model experiments conservatively projected an 11.75% increase in the number of waterbodies present by 2090–2099 compared to a baseline period from 1967 to 2005 in the PPR. Wetland‐dependent bird occurrence and abundance were significantly associated with temporal patterns and decadal periodicity in waterbody dynamics. Because of the strong associations between wetland‐dependent bird occurrence and abundance and the number of prairie potholes, projected waterbody increases are forecasted to result in an 11.97% overall increase in occurrence and 8.63% increase in abundance of the six focal species by the end of the 21st century; these results contrast with forecasted drought‐associated declines in waterbodies and birds in the PPR. This integrated hydrological–climatological approach offers a means of assessing how wetland‐dependent bird populations may respond to changes in wetland habitat availability due to a changing climate. Our results provide information that can help managers decide how to mitigate the effects of climate shifts on the distribution of wetland habitat and biota.
Quantifying risk of whale–vessel collisions across space, time, and management policies
Authors: Crum Nathan , Gowan Timothy , Krzystan Andrea , Martin Julien
Published: April 2019

Transportation industries can negatively impact wildlife populations, including through increased risk of mortality. To mitigate this risk successfully, managers and conservationists must estimate risk across space, time, and alternative management policies. Evaluating this risk at fine spatial and temporal scales can be challenging, especially in systems where wildlife–vehicle collisions are rare or imperfectly detected. The sizes and behaviors of wildlife and vehicles influence collision risk, as well as how much they co‐occur in space and time. We applied a modeling framework based on encounter theory to quantify the risk of lethal collisions between endangered North Atlantic right whales and vessels. Using Automatic Identification System vessel traffic data and spatially explicit estimates of right whale abundance that account for imperfect detection, we modeled risk at fine spatiotemporal scales before and after implementation of a vessel speed rule in the southeastern United States. The expected seasonal mortality rates of right whales decreased by 22% on average after the speed rule was implemented, indicating that the rule is effective at reducing lethal collisions. The rule's effect on risk was greatest where right whales were abundant and vessel traffic was heavy, and its effect varied considerably across time and space. Our framework is spatiotemporally flexible, process‐oriented, computationally efficient and accounts for uncertainty, making it an ideal approach for evaluating many wildlife management policies, including those regarding collisions between wildlife and vehicles and cases in which wildlife may encounter other dangerous features such as wind farms, seismic surveys, or fishing gear.
Plant community responses to stand‐level nutrient fertilization in a secondary tropical dry forest
Authors: Waring Bonnie G. , Pérez‐Aviles Daniel , Murray Jessica G. , Powers Jennifer S.
Published: April 2019

The size of the terrestrial carbon (C) sink is mediated by the availability of nutrients that limit plant growth. However, nutrient controls on primary productivity are poorly understood in the geographically extensive yet understudied tropical dry forest biome. To examine how nutrients influence above‐ and belowground biomass production in a secondary, seasonally dry tropical forest, we conducted a replicated, fully factorial nitrogen (N) and phosphorus (P) fertilization experiment at the stand scale in Guanacaste, Costa Rica. The production of leaves, wood, and fine roots was monitored through time; root colonization by mycorrhizal fungi and the abundance of N‐fixing root nodules were also quantified. In this seasonal forest, interannual variation in rainfall had the largest influence on stand‐level productivity, with lower biomass growth under drought. By contrast, aboveground productivity was generally not increased by nutrient addition, although fertilization enhanced growth of individual tree stems in a wet year. However, root growth increased markedly and consistently under P addition, significantly altering patterns of stand‐level biomass allocation to above‐ vs. belowground compartments. Although nutrients did not stimulate total biomass production at the community scale, N‐fixing legumes exhibited a twofold increase in woody growth in response to added P, accompanied by a dramatic increase in the abundance of root nodules. These data suggest that the relationship between nutrient availability and primary production in tropical dry forest is contingent on both water availability and plant functional diversity.
Contrasting vegetation states do not diverge in soil organic matter storage: evidence from historical sites in tundra
Authors: Stark Sari , Egelkraut Dagmar , Aronsson Kjell‐Åke , Olofsson Johan
Published: April 2019

Ecosystems where severe disturbance has induced permanent shifts in vegetation and soil processes may represent alternative stable states. To date, little is known on how long‐lasting changes in soil processes are following such disturbances, and how the changes in plant and soil processes between the alternative states eventually manifest themselves in soil organic matter (SOM) storage. Here, we analyzed plant density, the shrub : forb ratio, microbial respiration, extracellular enzyme activities and SOM stocks in soils of subarctic tundra and historical milking grounds, where reindeer herding induced a vegetation transition from deciduous shrubs to graminoids several centuries earlier but were abandoned a century ago. This provides the possibility to compare sites with similar topography, but highly contrasting vegetation for centuries. We found that enzymatic activities and N:P stoichiometry differed between control and disturbed sites, confirming that culturally induced vegetation shifts exert lasting impacts on tundra soil processes. Transition zones, where shrubs had encroached into the historical milking grounds during the past 50 yr, indicated that microbial activities for N and P acquisition changed more rapidly along a vegetation shift than those for microbial C acquisition. Although plant and soil processes differed between control and disturbed sites, we found no effect of historical vegetation transition on SOM stock. Across the study sites, soil SOM stocks were correlated with total plant density but not with the shrub : forb ratio. Our finding that SOM stock was insensitive to a centennial difference in plant community composition suggests that, as such, grazing‐induced alternative vegetation states might not necessarily differ in SOM sequestration.
Nitrogen fixation does not balance fire‐induced nitrogen losses in longleaf pine savannas
Authors: Tierney Julie A. , Hedin Lars O. , Wurzburger Nina
Published: April 2019

Fire is a critical force in structuring ecosystems, but it also removes substantial amounts of nitrogen (N), which can limit plant growth. Biological N fixation (BNF) may alleviate fire‐induced N deficiencies that inhibit ecosystem recovery, yet if and how BNF achieves this under frequent fire is unclear. This problem is further complicated in the context of modern human influences (such as land‐use history and atmospheric N deposition), which may confound the relationship between fire and fixation. Here, we investigate whether BNF supplies the N necessary to replace fire‐induced N losses in restored longleaf pine savannas, and, if so, what factors control fixation. We established 54 1‐ha plots of longleaf pine capturing 227 yr of forest recovery and a broad gradient of fire return interval (1.5–20 yr) at two sites in the southeastern United States. We quantified N fixation from three functional groups (herbaceous legumes, soil crusts, and asymbiotic N fixing bacteria), N losses from individual fire events and ecosystem dynamics of N supply and demand. We found that BNF rates were low but sustained over stand age but were substantially below estimated rates of atmospheric N deposition. While fire temporarily stimulated BNF from herbaceous legumes, neither BNF nor atmospheric N deposition were sufficient to balance N losses from fire and soil N stocks declined over stand age. However, rates of N mineralization were surprisingly high and tree productivity was unrelated to N availability, questioning the importance of N limitation in these temperate savannas. While it is possible that progressive N losses signal a decline in ecosystem resiliency, N enrichment from multiple land‐use transitions and anthropogenic N deposition may suppress rates of BNF or diminish its importance as a long‐term N balancing source in these pyrogenic ecosystems. In this case, fire may be acting as relief mechanism, critical for returning the modern longleaf pine landscape to its historical oligotrophic condition.
Synthesis of Structurally Diverse Benzotriazoles via Rapid Diazotization and Intramolecular Cyclization of 1,2‐Aryldiamines
Authors: Faggyas Réka J. , Sloan Nikki L. , Buijs Ned , Sutherland Andrew
Published: April 2019

An operationally simple method has been developed for the preparation of N‐unsubstituted benzotriazoles by diazotization and intramolecular cyclization of a wide range of 1,2‐aryldiamines under mild conditions, using a polymer‐supported nitrite reagent and p‐tosic acid. The functional group tolerance of this approach was further demonstrated with effective activation and cyclization of N‐alkyl, ‐aryl, and ‐acyl ortho‐aminoanilines leading to the synthesis of N1‐substituted benzotriazoles. The synthetic utility of this one‐pot heterocyclization process was exemplified with the preparation of a number of biologically and medicinally important benzotriazole scaffolds, including an α‐amino acid analogue.
Kilogram‐Scale Fabrication of Si/C Bean‐Structured Materials as Stable Anodes for Li‐Ion Storage
Authors: Liu Yang , Zhang Yinghan , Du Yu , Zhou Yunzhan , Hou Guolin , Lam Tran Dai , Yang Yijun , Yuan Fangli , Wang Xi
Published: April 2019

The practical application of Si‐based materials is widely impeded by poor electrochemical cycling stability. Here, inspired by the compact cladding and close connection structure of beans, an efficient buffering bean‐structured material of Si/C framework as a stable anode for Li‐ion storage is designed. By a simple ball‐milling process, the kilogram‐scale production of the Si/C can be realized. The Si/C composites exhibit excellent enhancement of electrochemical performance with a large storage capacity (1162.2 mAh g−1 at 0.1 C and 920.6 mAh g−1 at 0.2 C) and superior cycling stability (734 mAh g−1 after 200 cycles). The superior electrochemical performance is from the unique bean‐structured Si/C composites. Some micropores in porous carbon (PC) materials can offer void space that can alleviate stress and reduce volume expansion during the lithiation/delithiation process, and the PC can also act as a conductive matrix to enhance the conductivity and facilitate the diffusion of Li ions and electrons.