bluuebunny/crossref_metadata_2025 huggingface dataset:
Parallel evolution of arborescent carrots (Daucus) in Macaronesia
Authors: Frankiewicz Kamil E. , Oskolski Alexei , Banasiak Łukasz , Fernandes Francisco , Reduron Jean‐Pierre , Reyes‐Betancort Jorge‐Alfredo , Szczeparska Liliana , Alsarraf Mohammed , Baczyński Jakub , Spalik Krzysztof
Published: March 2020

Premise

Despite intensive research, the pathways and driving forces behind the evolution of derived woodiness on oceanic islands remain obscure. The genus Daucus comprises mostly herbs (therophytes, hemicryptophytes) with few rosette treelets (chamaephytes) endemic to various Macaronesian archipelagos, suggesting their independent evolution. To elucidate the evolutionary pathways to derived woodiness, we examined phylogenetic relationships and the habit and secondary xylem evolution in Daucus and related taxa.

Methods

Sixty taxa were surveyed for molecular markers, life history, and habit traits. Twenty‐one species were considered for wood anatomical characters. A dated phylogeny was estimated using Bayesian methods. The evolution of selected traits was reconstructed using parsimony and maximum likelihood.

Results

Daucus dispersed independently to the Canary Islands (and subsequently to Madeira), Cape Verde, and the Azores in the late Miocene and Pleistocene. Life span, reproductive strategy, and life form were highly homoplastic; the ancestor of Daucus was probably a monocarpic, biennial hemicryptophyte. Rosette treelets evolved independently in the Canarian‐Madeiran lineage and in Cape Verde, the latter within the last 0.13 Myr. Treelets and hemicryptophytes did not differ in wood anatomy. Pervasive axial parenchyma in wood occurred more often in polycarpic rather than monocarpic species.

Conclusions

Life span and life form in Daucus are evolutionarily labile and may change independently of wood anatomy, which is related to plant reproductive strategy rather than to life form. Insular woodiness may evolve rapidly (as demonstrated in D. bischoffii), and in Daucus, it does not seem to be an adaptation to lower the risk of xylem embolism.
A novel frameshift mutation in SOX10 causes Waardenburg syndrome with peripheral demyelinating neuropathy, visual impairment and the absence of Hirschsprung disease
Authors: Burke Elizabeth A. , Reichard Kyle E. , Wolfe Lynne A. , Brooks Brian P. , DiGiovanna John J. , Hadley Donald W. , Lehky Tanya J. , Gropman Andrea L. , Tifft Cynthia J. , Gahl William A. , Toro Camilo , Adams David
Published: March 2020

Waardenburg syndrome (WS) is a group of genetic disorders associated with varying components of sensorineural hearing loss and abnormal pigmentation of the hair, skin, and eyes. There exist four different WS subtypes, each defined by the absence or presence of additional features. One of the genes associated with WS is SOX10, a key transcription factor for the development of neural crest‐derived lineages. Here we report a 12‐year‐old boy with a novel de novo SOX10 frameshift mutation and unique combination of clinical features including primary peripheral demyelinating neuropathy, hearing loss and visual impairment but absence of Hirschsprung disease and the typical pigmentary changes of hair or skin. This expands the spectrum of currently recognized phenotypes associated with WS and illustrates the phenotypic heterogeneity of SOX10‐associated WS.
Strong Squeezing of Duffing Oscillator in a Highly Dissipative Optomechanical Cavity System
Authors: Xiong Biao , Li Xun , Chao Shi‐Lei , Yang Zhen , Peng Rui , Zhou Ling
Published: March 2020

In the conventional scheme of generating strong mechanical squeezing by the joint effect between mechanical parametric amplification and sideband cooling, the resolved sideband condition is required so as to overcome the quantum backaction heating. In the unresolved sideband regime, to suppress the quantum backaction, a χ(2) nonlinear medium is introduced to the cavity. The result shows that the quantum backaction heating effect caused by unwanted counter‐rotating term can be completely removed. Hence, the strong mechanical squeezing can be obtained even for the system far from the resolved‐sideband regime.
β‐Sheet to Helical‐Sheet Evolution Induced by Topochemical Polymerization: Cross‐α‐Amyloid‐like Packing in a Pseudoprotein with Gly‐Phe‐Gly Repeats
Authors: Hema Kuntrapakam , Sureshan Kana M.
Published: March 2020

Protein‐mimics are of great interest for their structure, stability, and properties. We are interested in the synthesis of protein‐mimics containing triazole linkages as peptide‐bond surrogate by topochemical azide‐alkyne cycloaddition (TAAC) polymerization of azide‐ and alkyne‐modified peptides. The rationally designed dipeptide N3‐CH2CO‐Phe‐NHCH2CCH (1) crystallized in a parallel β‐sheet arrangement and are head‐to‐tail aligned in a direction perpendicular to the β‐sheet‐direction. Upon heating, crystals of 1 underwent single‐crystal‐to‐single‐crystal polymerization forming a triazole‐linked pseudoprotein with Gly‐Phe‐Gly repeats. During TAAC polymerization, the pseudoprotein evolved as helical chains. These helical chains are laterally assembled by backbone hydrogen bonding in a direction perpendicular to the helical axis to form helical sheets. This interesting helical‐sheet orientation in the crystal resembles the cross‐α‐amyloids, where α‐helices are arranged laterally as sheets.
Physical Distance Between Romantic Partners as a Marker for Attachment in Couples: A Proof of Concept Study
Authors: Conradi Henk Jan , Noordhof Arjen , Boyette Lindy‐Lou , de Jonge Peter
Published: March 2020

Proximity seeking is at the core of attachment theory. Previously proximity has been studied almost exclusively in psychological terms. In clinical practice, however, couple therapists may interpret physical distance between romantic partners as a marker for the quality of the attachment bond. Unfortunately, this concept of physical distance between partners as an expression of attachment has never been tested. This study examines whether physical distance between romantic partners is associated with attachment. In 53 students and 43 clinical couples physical distance was repeatedly measured from video using novel software with excellent reliability. Attachment was measured with the Experiences in Close Relationships questionnaire. It was found that male attachment anxiety about rejection repeatedly showed statistically significant associations with physical interpersonal distance in student and clinical couples. We conclude that attachment may manifest itself not only in terms of psychological intimacy but also in terms of physical distance. Clinical utility and research implications are discussed.
Simulation study on novel groove separator in a dual‐loop wet flue gas desulfurization spray tower
Authors: Cui Lin , Lu Jingwen , Liu Lifei , Qin Mingchen , Dong Yong
Published: March 2020

The dual‐loop wet flue gas desulfurization spray tower (DLST) is particularly suitable for achieving “ultralow” emission of SO2 for high‐sulfur coal‐fired power plants. The separator is the key piece of equipment for the DLST. In this study, to overcome the disadvantages of a traditional bowl separator, novel groove separators are proposed and compared with the traditional separator. The effects of different separators on the flue gas flow characteristic, slurry droplet distribution, mass transfer resistance, and desulfurization efficiency were analyzed through numerical simulation based on the Euler–Lagrange method and two‐film theory. The results show that, compared with the traditional bowl separator, the proposed groove separator can improve the uniformity of the gas–liquid flow field in the upper loop, increase the liquid‐film side mass transfer rate significantly, eliminate the empty spaces caused by the high‐speed bypass flue gas, and avoid the “flooding” phenomenon completely. Therefore, the resistance losses caused by the separator can be reduced, the desulfurization efficiency can also be improved by adopting the novel groove separators, and the lower the liquid‐to‐gas ratio, the more obvious the increase in desulfurization efficiency. In general, the advantages of the novel groove separators over the traditional bowl separator are obvious.
Simultaneous improvement of thermal conductivity and mechanical properties for mechanically mixed ABS/h‐BN composites by using small amounts of hyperbranched polymer additives
Authors: Zhang Rong , Hu Hailong , Chen Hai , Li Siqi , Ying Cheng , Huang Shuai , Liu Qingting , Fu Xudong , Hu Shengfei , Wong Ching‐Ping
Published: March 2020

Recently, thermal interface materials (TIMs) are in great demands for modern electronics. For mechanically mixed polymer composite TIMs, the thermal conductivity and the mechanical properties are generally lower than expected values due to the sharply increased viscosity and poor filler dispersion. This work shows that addition of a small amount of polyester‐based hyperbranched polymer (HBP) avoided the trade‐off in mechanically mixed ABS/hexagonal boron nitride (h‐BN) composites. After adding 0.5 wt% HBP, the maximum h‐BN content in the composites increased from 50 to 60 wt%. The out‐of‐plane, in‐plane thermal conductivity, and tensile strength of ABS/h‐BN with 50 wt% h‐BN were 0.408, 0.517 W/mK, and 18 MPa, respectively, and were increased to 0.729, 0.847 W/mK, and 32 MPa by adding 0.5 wt% HBP, while 0.972, 1.12 W/mK, and 29.5 MPa were achieved for ABS/h‐BN/HBP with 60 wt% h‐BN. The morphological and rheological results proved that these enhancements are due to the improved h‐BN dispersion by decreasing viscosity of composites during mixing. Theoretical modeling based on the modified effective medium theory confirmed such results and showed that the interfacial thermal resistance also decreased slightly. Thus, this work demonstrates a facile and scalable method for simultaneously improving the thermal conductivity and mechanical properties of thermoplastic‐based TIMs.
Nonparametric universal copula modeling
Authors: Mukhopadhyay Subhadeep , Parzen Emanuel
Published: March 2020

To handle the ubiquitous problem of “dependence learning,” copulas are quickly becoming a pervasive tool across a wide range of data‐driven disciplines encompassing neuroscience, finance, econometrics, genomics, social science, machine learning, healthcare, and many more. At the same time, despite their practical value, the empirical methods of “learning copula from data” have been unsystematic with full of case‐specific recipes. Taking inspiration from modern LP‐nonparametrics, this paper presents a modest contribution to the need for a more unified and structured approach of copula modeling that is simultaneously valid for arbitrary combinations of continuous and discrete variables.
Deep learning for energy markets
Authors: Polson Michael , Sokolov Vadim
Published: March 2020

Deep Learning (DL) is combined with extreme value theory (EVT) to predict peak loads observed in energy grids. Forecasting energy loads and prices is challenging due to sharp peaks and troughs that arise due to supply and demand fluctuations from intraday system constraints. We propose a deep temporal extreme value model to capture these effects, which predicts the tail behavior of load spikes. Deep long‐short‐term memory architectures with rectified linear unit activation functions capture trends and temporal dependencies, while EVT captures highly volatile load spikes above a prespecified threshold. To illustrate our methodology, we develop forecasting models for hourly price and demand from the PJM interconnection. The goal is to show that DL‐EVT outperforms traditional methods, both in‐ and out‐of‐sample, by capturing the observed nonlinearities in prices and demand spikes. Finally, we conclude with directions for future research.
Therapeutic Effects of Bilateral Anodal Transcranial Direct Current Stimulation on Prefrontal and Motor Cortical Areas in Children with Autism Spectrum Disorders: A Pilot Study
Authors: Hadoush Hikmat , Nazzal Mohammad , Almasri Nihad A. , Khalil Hanan , Alafeef Maha
Published: March 2020

Dysfunctional frontal cortical areas associated with clinical features are observed in children with autism spectrum disorder (ASD). This study attempted to identify any potential therapeutic effects of bilateral anodal transcranial direct current stimulation (tDCS) applied over the left and right prefrontal and motor areas on the clinical characteristics of children with ASD. Fifty children with confirmed ASD medical diagnoses were divided equally and randomly into a tDCS treatment group and a control group. The tDCS treatment group underwent 10 sessions (20‐min durations, five per week) of bilateral anodal tDCS stimulation applied simultaneously over the left and right prefrontal and motor areas, whereas the control group underwent the same procedures but with the use of sham tDCS stimulation. Total scores and sub‐scores of autism treatment evaluation checklist (ATEC) (language and communication; sociability; sensory awareness; and behavioral, health, and physical conditions) were measured before and after the tDCS treatment sessions of both groups. There were significant decreases in total ATEC scores (P= 0.014), sociability sub‐scores (P= 0.021), and behavioral, health, and physical condition sub‐scores (P= 0.011) in the tDCS treatment group. No significant changes were observed in total ATEC scores and sub‐scores in the control group. In conclusion, compared to the control group, bilateral anodal tDCS showed potential therapeutic effects on children with ASD in terms of improvements in sociability, behavior, health, and physical conditions with no reported side effects.Autism Res2020, 13: 828–836. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.

Lay Summary

Dysfunctional frontal cortical areas are associated with clinical features in children with autism spectrum disorder (ASD). Transcranial direct current stimulation (tDCS) is found to be a safe, noninvasive method to stimulate cortical regions and thus have therapeutic effects on children with ASD. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.
Screening of cardioprotective diseases bioactive components from Danshen extracts and LC–MS analysis
Authors: Yuan Jiang‐Feng , Hu Jin‐Wan , Chen Zhuo‐Yao , Wang Da‐Hong
Published: March 2020

A rapid and efficient analysis and screening method is adopted for cell affinity capture coupled with HPLC–MS (CAC–HPLC–MS) analysis of bioactive components that have possible efficiency against cardiovascular diseases. This method involves affinity capture, concentration, and separation of bioactive components from Danshen library using oxidatively damaged endothelial cells induced by H2O2, as well as analysis and identification of targeted compounds with HPLC and MS. It combines the specific interaction between cell membrane receptors and bioactive components with the powerful analysis and identification function of HPLC–MS. The CAC–HPLC–MS method was also used for analysis and screening of bioactive components from crude extracts of Danshen. A total of 19 components were found to be bound to oxidatively damaged endothelial cells with seven of these identified. Existing literature confirms that these seven components have many activities related to cardioprotective diseases. Therefore, the combination of biological affinity capture with HPLC–MS should be regarded as an attractive method with great potential for rapid and efficient screening of bioactive components related to anti‐cardiovascular diseases from natural product libraries.
Prognostic significance of the radiologic features of pneumonitis induced by anti‐PD‐1 therapy
Authors: Watanabe Satoshi , Ota Takeshi , Hayashi Masachika , Ishikawa Hiroyuki , Otsubo Aya , Shoji Satoshi , Nozaki Koichiro , Ichikawa Kosuke , Kondo Rie , Miyabayashi Takao , Miura Satoru , Tanaka Hiroshi , Abe Tetsuya , Okajima Masaaki , Terada Masaki , Ishida Takashi , Iwashima Akira , Sato Kazuhiro , Yoshizawa Hirohisa , Kikuchi Toshiaki
Published: March 2020

Background

Interstitial lung disease (ILD) induced by anti‐programmed‐cell death‐1 (PD‐1) and anti‐PD‐ligand 1 (PD‐L1) is potentially life‐threatening and is a common reason of the discontinuation of therapy. In contrast, an enhancement in antitumor effects was reported in patients who developed immune‐related adverse events, including ILD. Although recent evidence suggests that radiologic patterns of ILD may reflect the severity of ILD and the antitumor immune responses to anti‐PD‐1/PD‐L1 therapies, the association between radiologic features and clinical outcomes remains unclear.

Methods

Patients with advanced non‐small‐cell lung cancer who were treated with 1st to 3rd line anti‐PD‐1 therapy from January 2016 through October 2017 were identified at multiple institutions belonging to the Niigata Lung Cancer Treatment Group. ILD was diagnosed by the treating physicians, and chest computed tomography scans were independently reviewed to assess the radiologic features of ILD.

Results

A total of 231 patients who received anti‐PD‐1 therapy were enrolled. Thirty‐one patients (14%) developed ILD. Sixteen patients were classified as having ground glass opacities (GGO), 16 were classified as having cryptogenic organizing pneumonia (COP), and one was classified as having pneumonitis not otherwise specified. Patients with GGO had significantly worse overall survival time compared to patients with COP (7.8 months (95% CI: 2.2‐NE) versus not reached (95% CI: 13.2‐NE); P = 0.0175). Multivariate analysis of all 231 patients also revealed that PS = 1 and ≥2 and GGO were significant predictors of a worse overall survival.

Conclusions

This study demonstrated that patients who developed GGO exhibited worse outcomes among non‐small‐cell lung cancer patients receiving anti‐PD‐1 therapies.
Surface‐Functionalized Graphite as Long Cycle Life Anode Materials for Lithium‐Ion Batteries
Authors: Gong Xiaohui , Zheng Yuanbo , Zheng Jiang , Cao Shengping , Wen Hui , Lin Baoping , Sun Yueming
Published: March 2020

Graphite is the major anode material of commercial lithium‐ion batteries (LIBs), and thus improving its cycling stability is an effective approach to extend battery life. In this study, succinic anhydride group, methoxyethanol, and methoxypolyethylene glycol segments are chemically bonded to the surfaces of graphite particles by the Diels‐Alder and the subsequent esterification reactions. The synthesized functionalized graphites are excellent in water dispersibility. The electrochemical results indicate that the functionalization slightly reduces the initial coulombic efficiencies of the graphite anodes, but significantly changes the cycling stability and high C‐rate performance of the corresponding lithium‐ion cells. In particular, the cell based on the graphite functionalized by long‐chain polyethylene glycol exhibits an improvement of 24.1 % in cycle life compared with the pristine graphite. Further analysis shows that these trace organic groups change the properties of the solid‐electrolyte interface (SEI) layer depositing on the graphite surfaces, and therefore influence the performance of the cells.
Influence of the NaOH Concentration on the Hydrogen Electrode Reaction Kinetics of Ni and NiCu Electrodes
Authors: Kuznetsov Aleksey N. , Oshchepkov Alexandr G. , Cherstiouk Olga V. , Simonov Pavel A. , Nazmutdinov Renat R. , Savinova Elena R. , Bonnefont Antoine
Published: March 2020

Nickel is a promising electrocatalyst for hydrogen electrode reactions in alkaline media. Its electrocatalytic activity for hydrogen oxidation and evolution reactions can be enhanced when its surface is partially covered by Ni (hydr)oxides or by associating it with Cu. In this work, the influence of the NaOH concentration on the hydrogen electrode kinetics on various Ni electrodes is investigated. On metallic Ni, the electrocatalytic activity (measured as an exchange current density normalized to the surface area of Ni) is almost constant between pH 12 and 14, whereas it decreases by a factor of two on partially oxidized Ni and on the NiCu/C electrode. Analyzing the current potential curves with the help of microkinetic modeling reveals that the Had and OHad binding energies on Ni do not depend on pH, whereas the rate constants of the Volmer and Heyrovsky reactions decrease with pH. The pH effect on the electron transfer elementary act is briefly discussed in the framework of a quantum mechanical theory.
EXPANSION OF CRÉTEIL SOLEIL SHOPPING CENTRE IN PARIS: DESIGN AND CONSTRUCTION OF STEEL AND COMPOSITE STRUCTURES
Authors: Augusto Hugo , Ribeiro César , Valério David , Ferreira Tiago , Pereira Marco , Gomes Filipe
Published: March 2020

The expansion of one of the largest shopping centres in France created the opportunity to develop solutions for large span floors and roofs, using steel and composite structures. Among the structures analysed the following are highlighted: the structure for the Mail area (food court) with welded I section beams with a height of 1.5m and 25m of span. And, the designated “Toiture Jonction”, which comprises two major beams with a span of about 30m, also made with welded I sections of 2.4m height. The several phases and challenges inherent to the design, manufacture and assembly will be addressed, from the technical point of view, supported in the value engineering involved, and the main steps to be considered to embrace a project of this nature are enumerated.
EXPERIMENTAL AND NUMERICAL INVESTIGATION ON THE STEEL BOX‐GIRDER BRIDGE DECKS WITH CURVED BOTTOM FLANGE
Authors: Ljubinković Filip , Pedro Martins João , Gervásio Helena , Simões da Silva Luís
Published: March 2020

In this paper, the results of the numerical parametric study are presented, in which the M‐V interaction behaviour of box‐girder bridge deck specimens was investigated. For this study, an advanced numerical model was used, previously calibrated against the experimental results. Based on the numerical results and the existent rules for the trapezoidal box‐girders, new design models were proposed for the prediction of the bending and shear resistance of cross‐sections with the curved bottom flange. Additionally, the force‐based M‐V interaction equation proposed by Jáger et al. [1] that is also adopted in the new version of EN 1993‐1‐5 [2] is verified and slightly modified to fit for this type of the cross‐section.
New Bridge Over Shire River, Malawi
Authors: Mendonça Tiago , Almeida Manuel , Rodrigues Bruno
Published: March 2020

This communication describes the major aspects concerning the design and construction of the new railway bridge over the Shire river, located on pk 275+133 of Limbe‐Nkaya railway line, in Malawi. This railway line makes the connection between Nkaya Junction and Limbe, in Blantyre and is used both for passengers and cargo.

The existing bridge has an advanced state of materials deterioration, resulting from maintenance difficulties, wear due to its exploration and high susceptibility to erosion phenomena. The cost‐benefit of an existing bridge rehabilitation intervention was quite unfavourable and the option for new bridge was found preferable.
EXPERIMENTAL STUDY ON DEEP‐COLUMN SUBJECT TO COMPRESSIVE AXIAL FORCE WITH ONE END CYCLIC BENDING MOMENT
Authors: Yoshioka Shimpei , Sato Atsushi , Onogi Takeshi
Published: March 2020

The design formulae of beam‐column are provided by Recommendation for Limit State Design of Steel Structures (LSD) in Japan. The design recommendation shown in LSD is derived from the test results that are basically obtained from one end monotonic bending moment. Therefore, it is necessary to examine whether these formulae can appropriately evaluate the strength of the beam‐column under cyclic loading condition. In this paper, the test results of the deep‐column are reported. The dimensions of the specimens were determined per LSD. Deep wide‐flange section H‐150×75×5×7 (unit: mm) is used for the specimen. From the testing, a few unconservative results were observed in LSD design formulae.
PARAMETRIC STUDY OF THE CURVED T‐STUB IN TENSION
Authors: Mudrov Andrej , Šapalas Antanas , Šaučiuvėnas Gintas
Published: March 2020

This paper presents parametric study of the T‐stubs with curved end‐plates in tension. Influence of the key parameters such as curvature, bolt arrangement and the thickness of the end‐plate on the strength and stiffness of the T‐stub is investigated. In curved T‐stubs bolts not only undergo tension, but are also subjected to shear, which limits the use of the conventional prying models. Apart shear, due to curvature, determination of the total effective length of a T‐stub is not trivial, and the collapse mechanisms of the end‐plate are uncertain. To clarify behaviour of the curved T‐stub and to determine the influence of the curvature on prying and shear, FEM results of 108 T‐stubs were analysed.
NUMERICAL EVALUATION OF DUPLEX STAINLESS STEEL STAYED COLUMNS
Authors: Ribeiro Danielle M. , da S. Vellasco Pedro C. G. , de Lima Luciano R. O. , de Araújo Ricardo R. , da Silva André T.
Published: March 2020

The use of prestressed stayed steel column systems in construction has numerous advantages related to its high strength and assembly flexibility. The present work aims to present an investigation of the structural behaviour of duplex stainless steel columns through a numerical modelling, using the finite element method, through the ANSYS program. The results confirmed that the use of cable prestress significantly increases the ultimate loads and ductility of the system, indicating the potential of these efficient and promising solutions. This was mainly due to their considerable resistance gain and numerous advantages in replacing carbon by stainless steel.
STRUCTURAL BEHAVIOUR OF JOINT BETWEEN STEEL BEAM AND CONCRETE ENCASED STEEL COMPOSITE COLUMN
Authors: Arita Masaki , Kitaoka Satoshi , Kanno Ryoichi , Nishida Yuichi , Liew J. Y. Richard , Iyama Jun
Published: March 2020

This paper is a study on the behaviour of a composite joint between a steel beam and a concrete encased steel composite column, where the steel beam is connected to a steel column by a fin‐plate connection and the steel column and joint are subsequently encased by reinforced concrete to form a composite column. This joint is named “embedded joint”. Although this type of joints is designed as a simple pin joint in practice, it can transfer a fair amount of shear force and bending moment primarily through bearing stress between the steel beam and the surrounding concrete. To propose a rational joint behavioural model in line with the current Eurocodes, the bearing component of base plate connections shown in EN1993‐1‐8 is firstly applied. The proposed model is then compared with full‐scale joint loading tests to verify its accuracy in predicting the rotational stiffness and the moment resistance.
FIRE RESISTANCE OF STAINLESS STEEL AXIALLY LOADED ELLIPTICAL HOLLOW SECTION COLUMNS
Authors: Arrais Flávio , Lopes Nuno , Real Paulo Vila
Published: March 2020

In spite of the initial cost of stainless steel, its application as a structural material has been increasing. Stainless steel has different advantages when compared to conventional carbon steel. The corrosion resistance and aesthetic appearance are the most known, but its higher fire resistance can also be decisive. This work presents a numerical study on the behaviour of stainless steel members composed of elliptical hollow sections subjected to axial compression at elevated temperatures. The numerical ultimate load bearing capacities were obtained applying finite element models and the results were compared with simplified calculation formulae from Eurocode 3, concluding that this methodology is not appropriate for the type of profiles here analysed.
WELDED T‐JOINTS BETWEEN RECTANGULAR HOLLOW SECTION MEMBERS WITH OFFSET
Authors: Kalmykova Svitlana , Wald František
Published: March 2020

The current study is devoted to mechanical resistance of so‐called offset welded RHS joints where RHS brace members are offset from the chord centreline under brace axial compression. Paper presents numerical investigation results of structural behaviour of mentioned joints under monotonically increased load. For these purposes, Abaqus FE‐models were developed by using C3D8R 8‐noded solid linear brick elements with attention to mesh size effect and weld modelling. The force‐displacement curves corresponding to different geometries of joints were analysed focusing on the failure modes. Based on conducted numerical simulations, deformation limits and failure criteria for offset joints were adopted and verified. It is stated that the 3%b0 ultimate deformation limit chosen by Lu et al. (1994) and adopted by the IIW as main criterion of joints' failure could be reasonable revised.
COMPOSITE BEHAVIOUR OF COLD‐FORMED STEEL ‐ TIMBER FLOORS
Authors: Raffoul Samar , Moutaftsis Dimitrios , Heywood Martin , Rowell Michael
Published: March 2020

This article investigates, experimentally, the structural performance of lightweight cold‐formed steel (CFS) ‐ timber board composite flooring systems. Fifteen full‐scale bending tests and twelve companion pushout connection tests were performed. The effect of connection detail (comprising self‐drilling screws with or without a structural adhesive) on structural performance is examined. The results of this research demonstrate that the use of a polyurethane adhesive, in conjunction with screws, leads to a significant increase in connection slip modulus and a higher degree of composite action in the floors, resulting in up to 40% increase in flexural stiffness, when compared to joists designed individually. The experimental results are then compared to predictions from relevant existing analytical models.
STABILITY OF STRUTS AND FRAMES: BACKGROUND AND DESIGN METHODS ACCORDING TO EUROCODE 3
Authors: Pimentel Ricardo J. A. G. , Simões Rui A. D.
Published: March 2020

Structural stability is one of the key aspects in the structural engineering practice. Following current architectural trends, steel and composite structures tend to be slender and flexible, which may lead to a necessity to consider the deformed structural shape to the analysis and design. This paper provides a background overview about structural stability and second order effects according to the Eurocode 3. The proposed methods for addressing these effects according to The Eurocode 3 will be presented. Computational methods to assess structural stability will be discussed. Practical design examples for each Eurocode method are presented.
NUMERICAL ANALYSIS WITH IMPLEMENTATION OF DAMAGE TO STAINLESS STEEL BOLTED CONNECTIONS SUBJECTED TO SHEAR LOAD
Authors: Sobrinho Kelvin P. , Silva André T. , Rodrigues Monique C. , Henriques José A. G. , Vellasco Pedro C. G. S. , Lima Luciano R. O.
Published: March 2020

In this paper, an experimental and numerical study were developed to evaluate the behavior of stainless steel bolted connections subjected to shear load until rupture, in which austenitic stainless steel 304 was used. In order to determine the material behavior, tensile coupon tests were performed. The numerical model was developed in Abaqus finite element program using dynamic explicit analysis and solid elements (C3D8) with an elastic‐plastic stress‐strain curve with strain hardening and damage criteria. Additionally, a comparison of the results with the recommendations given by the current standards for stainless steel structures was also accomplished.
Interception of Elusive Cationic Hf–Al and Hf–Zn Heterobimetallic Adducts with Mixed Alkyl Bridges Featuring Multiple Agostic Interactions
Authors: Tensi Leonardo , Froese Robert D. J. , Kuhlman Roger L. , Macchioni Alceo , Zuccaccia Cristiano
Published: March 2020

Invited for the cover of this issue is the group of Cristiano Zuccaccia at the Università degli Studi di Perugia. The image depicts a relation of the nuances of chemical bonding to the diverse ways that animals “bind” to their natural surroundings. Read the full text of the article at 10.1002/chem.201905699.
Pressure dependence of vibrational optical activity of model biomolecules. A computational study
Authors: Plamitzer Luboš , Bouř Petr
Published: March 2020

Change of molecular properties with pressure is an attracting means to regulate molecular reactivity or biological activity. However, the effect is usually small and so far explored rather scarcely. To obtain a deeper insight and estimate the sensitivity of vibrational optical activity spectra to pressure‐induced conformational changes, we investigate small model molecules. The Ala‐Ala dipeptide, isomaltose disaccharide and adenine‐uracil dinucleotide were chosen to represent three different biomolecular classes.

The pressure effects were modeled by molecular dynamics and density functional theory simulations. The dinucleotide was found to be the most sensitive to the pressure, whereas for the disaccharide the smallest changes are predicted. Pressure‐induced relative intensity changes in vibrational circular dichroism and Raman optical activity spectra are predicted to be 2–3‐times larger than for non‐polarized IR and Raman techniques.
Kinetic Modeling of Rhodium‐Catalyzed Reductive Amination of Undecanal in Different Solvent Systems
Authors: Kirschtowski Sabine , Kadar Christof , Seidel‐Morgenstern Andreas , Hamel Christof
Published: March 2020

The homogenously rhodium‐catalyzed reductive amination of 1‐undecanal was performed in two different thermomorphic solvent systems with the ligand Xantphos. The influences of partial pressure, temperature, methanol and catalyst concentration on the reaction were investigated. Based on a network analysis a kinetic model was derived and successfully parametrized for all studied solvent systems. Simulation results were found to be in good agreement with the experiments and allow a further process development and optimization.
Phase Engineering of Two‐Dimensional Transition Metal Dichalcogenides
Authors: Qian Ziyue , Jiao Liying , Xie Liming
Published: March 2020

Transition metal dichalcogenides (TMDs) possess a large number of two‐dimensional (2D) materials with novel physical and chemical properties and hold great potential applications in electronic devices, optical devices as well as catalysts. TMDs usually have poly‐phases, such as 2H, 3R and 1T. Chemical and physical properties, including electrical conductivity, superconductivity, magnetism and catalytic activity, are different for different phases of TMDs. Therefore, great efforts have been made to obtain a specific pure phase of 2D TMD materials. Here, we review the recent phase engineering research for 2D TMDs, including ion insertion, alloying, temperature, defects, strain and electric field.
Diversity and heterotic patterns in North American proprietary dent maize germplasm
Authors: White Michael R. , Mikel Mark A. , de Leon Natalia , Kaeppler Shawn M.
Published: March 2020

Publicly available maize (Zea mays L.) inbred lines with expired Plant Variety Protection certificates (ex‐PVP) constitute the elite germplasm used in hybrids grown by North American farmers during the past half century. A set of 329 ex‐PVP inbreds and eight public reference inbreds was evaluated for genetic diversity using molecular marker and pedigree‐based relationships. The majority of inbreds originated from Dekalb Genetics Corporation, Holden's Foundation Seed, Pioneer Hi‐Bred International, and Syngenta via Novartis and Northrup King. Flowering ranged from 968–1806 growing degree days to anthesis, supporting that these inbreds represent adaptation across the range of North American production environments. Admixture analysis supported eight subgroups (B14, B37, B73, Oh43, Iodent, Iodent‐Lancaster, Lancaster, and Flint), reflecting heterotic patterns and company of origin. Five diallel‐cross experiments identified primary yield heterotic patterns within early‐, intermediate‐, and late‐maturity groups. Parental pedigree information was compiled for 2392 Plant Variety Protection and/or utility patented inbreds through 2017, allowing for multigenerational analysis of progenitors and the eight heterotic subgroups across current proprietary breeding programs. Key progenitors were identified for recently merged companies, Bayer Crop Science and Corteva Agriscience. The results of this study strengthen the value of the ex‐PVP inbreds as a source of elite and relevant germplasm for breeders and researchers to exploit. This study provides information that will be logistically useful to researchers who use ex‐PVP inbreds and adds to our understanding of heterotic grouping within North American proprietary germplasm.
Impact of cultivar and environment soil suitability on the contribution of yield components to grain yield variation in spring wheat
Authors: Sobczyński Grzegorz , Studnicki Marcin , Mądry Wiesław , Wijata Magdalena , Gozdowski Dariusz , Noras Kinga , Samborski Stanisław , Rozbicki Jan
Published: March 2020

The objectives of this study were to determine how modern cultivars of spring wheat (Triticum aestivum L. var. vulgare) and different soil conditions at locations in Poland affected grain yield (GY) of 15 cultivars and multiplicative yield components. The different ways in which the components contributed to GY variation created by environmental conditions—location, growing season, and crop management—across environments of favorable and unfavorable soil suitability for wheat cultivation were also determined. To assess the relationship between GY and its components for cultivars grown under two levels of soil suitability, path coefficient analysis was used. Cluster analysis of three GY components—the number of spikes per square meter (SN), the number of grains per spike (NG/S), and the thousand‐grain weight (TGW)—derived from different cultivar × soil suitability combinations was performed to identify groups of these combinations and to assess the ways in which yield components vary in their contribution to GY in the varied environments. Grain yield and its three components were significantly affected by main and interaction effects of the cultivar and the level of soil suitability. Grain yield in favorable and unfavorable soil suitability conditions was, respectively, 6.58–5.44 Mg ha−1. This decrease was due to a reduction in SN by 6.1% and in TGW by 11.8%, but NG/S was similar in both soil groups. Grain yield variability in response to the different environmental conditions was determined by similar contributions of the three yield components, almost independently of the cultivar, but in the favorable suitability, SN had a stronger impact on GY, whereas in unfavorable soil suitability for wheat cultivation, the importance of NG/S increased.
Evaluation of the genetic diversity in the feijoa accessions maintained at Santa Catarina, Brazil
Authors: Saifert Luciano , Sánchez‐Mora Fernando David , Borsuk Lido José , Donazzolo Joel , da Costa Newton Clóvis Freitas , Ribeiro Humberto Nunes , Nodari Rubens Onofre
Published: March 2020

Feijoa [Acca sellowaiana (O. Berg) Burret], also known as pineapple guava or goiabeira‐serrana, is a species of the Myrtaceae family native to southern Brazil and Uruguay. The genetic diversity of feijoa's natural populations has been studied and is relatively well‐documented; however, the genetic diversity of feijoa accessions in the largest active germplasm bank (AGB) in Brazil, and is still poorly documented. Characterizing and conserving pineapple guava accessions present in the AGB is essential for developing breeding programs and conserving the diversity of the species. Thus, the objective of this study was to characterize the genetic diversity of all accessions using eight microsatellite markers. The AGB collection includes accessions from 26 municipalities in Brazil, New Zealand, the United States, Israel, and Uruguay; selected clones, and selections of directed crossings, totaling 313 accessions. Genotyping 309 of these accessions with eight microsatellite markers revealed 119 alleles. Polymorphism information content (PIC) values varied between .466 (ASE40) and .890 (ASE34) with an overall mean of .718. This genotyping confirms the existence of two main types or biotypes in the species, denoted as the Uruguay type and Brazil type. Also, a significant proportion of the feijoa diversity, which is absent from the AGB‐Feijoa collection, is present in germplasm maintained by indigenous people, quilombola communities, federal conservation units, participatory genetic breeding, and areas of natural occurrence, thus reinforcing the need to introduce new accessions into São Joaquim's AGB‐Feijoa.
Two‐Dimensional Transition Metal Chalcogenides for Alkali Metal Ions Storage
Authors: Zhang Yingxi , Zhang Liao , Lv Tu'an , Chu Paul K. , Huo Kaifu
Published: March 2020

On the heels of exacerbating environmental concerns and ever‐growing global energy demand, development of high‐performance renewable energy‐storage and ‐conversion devices has aroused great interest. The electrode materials, which are the critical components in electrochemical energy storage (EES) devices, largely determine the energy‐storage properties, and the development of suitable active electrode materials is crucial to achieve efficient and environmentally friendly EES technologies albeit the challenges. Two‐dimensional transition‐metal chalcogenides (2D TMDs) are promising electrode materials in alkali metal ion batteries and supercapacitors because of ample interlayer space, large specific surface areas, fast ion‐transfer kinetics, and large theoretical capacities achieved through intercalation and conversion reactions. However, they generally suffer from low electronic conductivities as well as substantial volume change and irreversible side reactions during the charge/discharge process, which result in poor cycling stability, poor rate performance, and low round‐trip efficiency. In this Review, recent advances of 2D TMDs‐based electrode materials for alkali metal‐ion energy‐storage devices with the focus on lithium‐ion batteries (LIBs), sodium‐ion batteries (SIBs), potassium‐ion batteries (PIBs), high‐energy lithium–sulfur (Li–S), and lithium–air (Li–O2) batteries are described. The challenges and future directions of 2D TMDs‐based electrode materials for high‐performance LIBs, SIBs, PIBs, Li–S, and Li–O2 batteries as well as emerging alkali metal‐ion capacitors are also discussed.
Tips to make dual‐enrollment programs run smoothly
Authors: Hamblet Elizabeth C.
Published: March 2020

Dual‐enrollment classes can be a great opportunity for students to prepare for the college environment. For students with disabilities, enrolling in them also means adjustment to a different accommodation system. To make sure things run smoothly, work with all of the stakeholders involved. Teressa Eastman, Director of Disability Services at Butler Community College; and Jenifer Montag, Director of Student Disability Services at Marion Technical College, offer some helpful tips.
Application of the Brook Rearrangement in Tandem with Single Electron Transfer Oxidative and Radical Processes
Authors: Klychnikov Mikhail K. , Pohl Radek , Císařová Ivana , Jahn Ullrich
Published: March 2020

Merging rearrangement with radical reactions is a largely unexplored field but may hold promise for approaching scaffolds that are inaccessible by other methodology. Here a tandem nucleophilic substitution/Brook rearrangement/single‐electron transfer oxidation/radical oxygenation strategy is presented, through which α,γ‐dioxygenated ε,ζ‐unsaturated amides are efficiently prepared in a single step from enantiomerically enriched allylepoxides and 2‐silylacetamides. The resulting compounds can be easily transformed by persistent radical effect‐based 5‐exo‐trig or 6‐endo‐trig radical cyclization reactions to functionalized carbocycles bearing three or four stereocenters. The stereochemical outcome of the cyclization reactions can predicted by the Beckwith–Houk model. The cyclic compounds can be easily diversified by post‐cyclization modifications. The tandem process can be further extended by an acylation step leading to β‐dicarbonyl enolates, which were also transformed to cyclopentane and cyclohexane derivatives under oxidative conditions.
Development and Application of Pyridinium 1,4‐Zwitterionic Thiolates: Synthesis of Polysubstituted Thiophenes
Authors: Cheng Bin , Duan Xiaoguang , Li Yuntong , Zhang Xinping , Li Hui , Wu Fufang , Li Yun , Wang Taimin , Zhai Hongbin
Published: March 2020

Pyridinium 1,4‐zwitterionic thiolates as a class of sulfur‐containing synthons were applied to a [3+2] cascade cyclization reaction with activated alkynes, affording a library of polysubstituted thiophenes with excellent regioselectivities, especially those bearing various fluorine‐containing groups. The freshly disclosed pyridinium 1,4‐zwitterionic thiolates decorated with acyl or trifluoromethyl groups exhibited powerful potential in the synthesis of polysubstituted thiophenes. Of particular note is that pyridinium A4 could introduce sulfur and CF3 groups to target products simultaneously.
Fault Diagnostics in PEMFC Stacks by Evaluation of Local Performance and Cell Impedance Analysis
Authors: Mitzel J. , Sanchez‐Monreal J. , Garcia‐Sanchez D. , Gazdzicki P. , Schulze M. , Häußler F. , Hunger J. , Schlumberger G. , Janicka E. , Mielniczek M. , Gawel L.
Published: March 2020

Starvation, flooding, and dry‐out phenomena occur in polymer electrolyte membrane fuel cells (PEMFCs), due to heterogeneous local conditions, material inhomogeneity, and uneven flow distribution across the single cell active area and in between the individual cells. The impact of the load level and air feed conditions on the performance was identified for individual single cells within a 10‐cell stack. Analysis of the current density distribution across the active area at the cell level was correlated with electrochemical impedance spectroscopy to enable operando fault diagnostic without any impact of the applied analytical tools on the single cell behavior. Moreover, the combination of both technologies allows in‐depth analysis of fault mechanisms in fuel cell single cells with improved sensitivity. Current density distribution and the quantitative assessment of the performance homogeneity demonstrated high sensitivity to small humidity changes and allow the detection of critical events, such as dry‐out in single cells. Impedance analysis is more sensitive regarding polarization and diffusion limitations and allows detection of cell flooding. The combination of both techniques is required for reliable identification of air starvation faults.
Network failures: When incentives trigger impulsive responses
Authors: Zhukovsky Peter , Morein‐Zamir Sharon , Meng Chun , Dalley Jeffrey W. , Ersche Karen D.
Published: March 2020

Adequate control of impulsive urges to act is demanded in everyday life but is impaired in neuropsychiatric conditions such as stimulant use disorder. Despite intensive research it remains unclear whether failures in impulse control are caused by impaired suppression of behavior or by the over invigoration of behavior by stimuli associated with salient incentives such as drugs, food, and money. We investigated failures in impulse control using functional magnetic resonance imaging (fMRI) to map the neural correlates of premature (impulsive) responses during the anticipation phase of the Monetary Incentive Delay (MID) task in healthy controls (HC), stimulant‐dependent individuals (SDIs), and their unaffected first‐degree siblings (SIB). We combined task‐based fMRI analyses with dynamic causal modeling to show that failures of impulse control were associated with interactions between cingulo‐opercular and dorsal striatal networks regardless of group status and incentive type. We further report that group‐specific incentive salience plays a critical role in modulating impulsivity in SDIs since drug‐related incentives specifically increased premature responding and shifted task modulation away from the dorsal striatal network to the cingulo‐opercular network. Our findings thus indicate that impulsive actions are elicited by salient personally‐relevant incentive stimuli and those such slips of action recruit a distinct fronto‐striatal network.