bluuebunny/crossref_metadata_2025 huggingface dataset:
An evidence‐based structured one‐year programme to sustain physical activity in patients with heart failure in primary care: A non‐randomized longitudinal feasibility study
Authors: Nordgren Lena , Söderlund Anne
Published: May 2020

Aim

The primary objective of this non‐randomized feasibility study was to test a 1‐year model programme for sustaining/increasing patients’ motivation to perform daily physical activity.

Design

Non‐randomized longitudinal feasibility study with a one‐group repeated measures design.

Methods

The study took place at a primary care centre in mid‐Sweden in 2017–2018. The model programme included individual and group‐based support, individualized physical activity prescriptions, a wrist‐worn activity tracker and an activity diary. The main outcomes were the participants’ perceptions of programme feasibility and scores on the Exercise Self‐Efficacy Scale.

Results

Seven patients were recruited. Six patients completed the programme that was perceived to imply learning, motivation and support. Compared with baseline, the median score of the Exercise Self‐Efficacy Scale improved 3 months after participants completed the programme.
Two‐grid methods for –P1 mixed finite element approximation of general elliptic optimal control problems with low regularity
Authors: Hou Tianliang , Leng Haitao , Luan Tian
Published: May 2020

In this paper, we present a two‐grid mixed finite element scheme for distributed optimal control governed by general elliptic equations. –P1 mixed finite elements are used for the discretization of the state and co‐state variables, whereas piecewise constant function is used to approximate the control variable. We first use a new approach to obtain the superclose property between the centroid interpolation and the numerical solution of the optimal control u with order h2 under the low regularity. Based on the superclose property, we derive the optimal a priori error estimates. Then, using a postprocessing projection operator, we get a second‐order superconvergent result for the control u. Next, we construct a two‐grid mixed finite element scheme and analyze a priori error estimates. In the two‐grid scheme, the solution of the elliptic optimal control problem on a fine grid is reduced to the solution of the elliptic optimal control problem on a much coarser grid and the solution of a linear algebraic system on the fine grid and the resulting solution still maintains an asymptotically optimal accuracy. Finally, a numerical example is presented to verify the theoretical results.
The effect of polyhedral oligosilsesquioxanes (POSS) on cavitation resistance of hybrid acrylate films
Authors: Kalifa Mustafa , Tomić Nataša Z. , Vuksanović Marija M. , Stevanovic Sanja , Đokić Veljko , Husović Tatjana Volkov , Pavlović Vladimir , Jančić Heinemann Radmila M. , Marinković Aleksandar D.
Published: May 2020

Cavitation erosion of hybrid acrylate composite films with polyhedral oligosilsesquioxanes (POSS) was investigated in this study. The hybrid films are made with 1, 3 and 5 wt% of POSS reagents containing: (a) hydroxyl (POSS‐M), (b) both hydroxyl and allyl (POSS‐M‐A) and (c) methacryloyl groups (POSS‐M‐Cl). Addition of 5 wt% POSS‐M‐A caused the highest microhardness increase for 49.8%, in comparison to the pure matrix material. Cavitation resistance of hybrid films, estimated as the time‐dependent mass loss, was improved by POSS addition. POSS‐M‐A addition (5 wt%) contributed to 94% lower mass loss comparing to pure Bis‐GMA/TEGDMA film. Scanning electron (SEM) and atomic force microscopy (AFM) showed the lowest surface roughness obtained for composite with POSS‐M‐A. The improved hardness and wear resistance of the composite films indicated that POSS‐M‐A filler enhanced interfacial adhesion and reinforcing of the Bis‐GMA/TEGDMA matrix.
Intermittent absent and reversed umbilical artery flows in appropriately grown monochorionic diamniotic twins in relation to proximate cord insertion: A harmful combination?
Authors: Eschbach Sanne Johanna , Tollenaar Lisanne S. A. , Oepkes Dick , Lopriore Enrico , Haak Monique C.
Published: May 2020

Objective

To compare the prevalence of intermittent absent or reversed end‐diastolic flow (iAREDF) in the umbilical artery in appropriately grown monochorionic diamniotic (MCDA) pregnancies with and without proximate cord insertion (PCI), and to evaluate pregnancy outcome.

Methods

The prevalence of iAREDF in MCDA pregnancies with PCI (n = 11) was compared with a control group without PCI (n = 33). PCI was defined as a distance between the cord insertions below the fifth percentile. Placental sharing, number, and diameter of anastomoses were assessed by placental examination. Pregnancy outcome was evaluated.

Results

iAREDF was present in 7/11 PCI pregnancies, compared with 0/33 in the control group (P ≤ .01). All PCI pregnancies and 94% of controls had arterioarterial (AA)‐anastomoses (P = .56), the diameter was larger in the PCI group, respectively 3.3 vs 2.1 mm (P = .03). Three cases with iAREDF had adverse outcome, two resulted in fetal death of which one with brain damage in the co‐twin, another underwent early premature emergency section for fetal distress.

Conclusion

iAREDF occurs in a large proportion of MCDA pregnancies with PCI and is related to the diameter of the AA anastomosis. We hypothesize that iAREDF in appropriately grown MCDA twin pregnancies reflects an unstable hemodynamic balance with an increased risk for fetal deterioration. Whether outcome in these pregnancies can be improved by altered management requires further investigation.
I am all ears: Maximize maize doubled haploid success by promoting axillary branch elongation
Authors: Wu Miin‐Feng , Goldshmidt Alexander , Ovadya Daniel , Larue Huachun
Published: May 2020

The maize doubled haploid (DH) technology plays an important role in accelerating breeding genetic gain. One major challenge in fully leveraging the potential of DH technology to accelerate genetic gain is obtaining a consistent seed return from haploid (DH0) plants after chromosome doubling. Here we demonstrated that DH0 seed production can be increased by increasing the number of mature axillary female inflorescences (ears) at anthesis. To determine the maximum capacity of a maize plant to develop ears, we first characterized the developmental progression of every axillary meristem. We found that all axillary meristems developed to a similar developmental stage before the reproductive transition of the shoot apical meristem (SAM). Upon reproductive transition of the SAM, all axillary meristems are released for reproductive development into ears in a developmental gradient reflective on their positions along the main stem. However, under most circumstances only the top one or two ears can generate silks at anthesis. We found that applying the GA inhibitor paclobutrazol (PAC) during the early reproductive transition of axillary meristems increased the number of silking ears at anthesis, leading to increased success of self‐pollination and seed production. These results provide a blueprint to improve DH efficiency and demonstrate the potential of breeding innovation through understanding crops’ developmental processes.
Interrogating Fractionation and Other Sources of Variability in Shotgun Proteomes Using Quality Metrics
Authors: Kriek Marina , Monyai Koena , Magcwebeba Tandeka U. , Du Plessis Nelita , Stoychev Stoyan H. , Tabb David L.
Published: May 2020

The increasing amount of publicly available proteomics data creates opportunities for data scientists to investigate quality metrics in novel ways. QuaMeter IDFree is used to generate quality metrics from 665 RAW files and 97 WIFF files representing publicly available “shotgun” mass spectrometry datasets. These experiments are selected to represent Mycobacterium tuberculosis lysates, mouse MDSCs, and exosomes derived from human cell lines. Machine learning techniques are demonstrated to detect outliers within experiments and it is shown that quality metrics may be used to distinguish sources of variability among these experiments. In particular, the findings demonstrate that according to nested ANOVA performed on an SDS‐PAGE shotgun principal component analysis, runs of fractions from the same gel regions cluster together rather than technical replicates, close temporal proximity, or even biological samples. This indicates that the individual fraction may have had a higher impact on the quality metrics than other factors. In addition, sample type, instrument type, mass analyzer, fragmentation technique, and digestion enzyme are identified as sources of variability. From a quality control perspective, the importance of study design and in particular, the run order, is illustrated in seeking ways to limit the impact of technical variability.
Cannabidiol for Dravet and Lennox‐Gastaut syndromes: NICE guidance
Authors: Gaber Tarek
Published: May 2020

Recent NICE guidance on the use of cannabidiol for two rare epilepsy syndromes could be seen as a crucial step in the acceptance of a medical role for cannabis derivatives. Formal trial evidence and official recommendation for the use of what has been regarded by many as a controversial substance for medicinal use should help those who may derive benefit to access it.
Treatment of psychosis in Huntington's disease with clozapine
Authors: Majothi Naeema , Lee Hean Yeung , Nagarajan Pankajam , Vutla Raghu
Published: May 2020

There is limited evidence relating to the treatment of psychotic symptoms in Huntington's disease (HP); therefore, treatment decisions are based on clinical consensus and expert opinion. In this article, Dr Majothi et al. describe the use of clozapine in an unlicensed manner in HP, which proved to be safe and effective.
Introduction of an Al Seed Layer for Facile Adsorption of MoCl5 during Atomic Layer Deposition of MoS2
Authors: Ahn Wonsik , Lee Hyangsook , Cho Yeonchoo , Byun Kyung-Eun , Kim Hoijoon , Leem Mirine , Lee Heesoo , Park Taejin , Lee Eunha , Shin Hyeon-Jin , Kim Hyoungsub
Published: May 2020

A low‐temperature one‐step growth method for few‐layer MoS2 using an atomic layer deposition scheme with MoCl5 and H2S precursors is systematically studied by introducing an ultrathin Al seed layer. First, to optimize the deposition conditions, the effects of the deposition (200–420 °C) and MoCl5 canister (100–160 °C) temperatures on the MoS2 growth behavior are investigated. On the SiO2 surface, increasing the deposition temperature reduces the growth rate while favoring more lateral growth. However, an increase in the MoCl5 sublimating temperature, which is beneficial to improve the film quality, sharply reduces the growth rate, probably owing to the pronounced self‐etching effect of MoCl5. To compensate for the reduced deposition rate while maintaining the MoS2 quality, an ultrathin Al seed layer (≈5 nm) is introduced, which promotes the surface adsorption of MoCl5 molecules at an early growth stage according to density functional theory calculations. Thus, a polycrystalline mono‐to‐bilayer MoS2 film with negligible amounts of residual contaminants (particularly Cl and Al) is successfully synthesized using the proposed Al seeding approach.
Functionalized Naphthalene Diimides as Low‐Cost Organic Cathodes for Potassium Batteries
Authors: Blokhina Anastasiia D. , Kozlov Alexey V. , Klimovich Irina V. , Troshin Pavel A.
Published: May 2020

Herein, the synthesis and investigation of two naphthalene diimide derivatives with the ethylenesulfonic (NDI1) and methylenecarboxylic (NDI2) groups appended to diimide nitrogen atoms in the form of potassium salts are reported. Synthesized compounds are characterized by 1H NMR, 13C NMR, and elemental analysis. Electrochemical performance of the diimides is evaluated in half‐cells with potassium anodes. Both materials show a decent specific capacity of 86–96 mAh g−1 at the first cycle at C/10 current rate in combination with average cell discharge potentials approaching 2.2 V. The obtained results suggest that synthesized materials can be considered as cheap electrode materials for potassium batteries designed for stationary energy storage applications.
Directing the Morphology of Chemical Vapor Deposition‐Grown MoS2 on Sapphire by Crystal Plane Selection
Authors: Peters Lisanne , Ó Coileáin Cormac , Dluzynski Patryk , Siris Rita , Duesberg Georg S. , McEvoy Niall
Published: May 2020

Crystalline substrates are known to function as a template for the growth of Van der Waals materials. Van der Waals materials, specifically transition metal dichalcogenides, have gained attention in the past decade due to their interesting chemical and physical properties, as well as the potential they hold for applications, particularly in the field of (opto‐)electronics. The crystalline quality of these materials can be improved by epitaxial growth. Herein, the influence substrate selection has on ordering the growth of MoS2 is examined. Specifically, the impact sapphire crystal orientation has on the morphology and alignment of MoS2 grown by chemical vapor deposition is investigated. C‐plane , R‐plane , A‐plane , and M‐plane Al2O3 substrates, annealed at high temperature in air, are used as templates for MoS2 growth. Comparative analysis, including photoluminescence spectroscopy, Raman spectroscopy, and atomic force microscopy, reveals distinct characteristics and growth modes depending on the growth substrate used. It is found that aligned growth of MoS2 is influenced by the terrace size, atomic steps, and substrate interaction with the MoS2. Aligned growth occurs on both R‐ and M‐plane sapphire. For A‐plane sapphire, the MoS2 flakes are variable in size and thickness. The weakest substrate interaction is observed for growth on C‐plane sapphire, which consists of randomly oriented flakes.
On the Holton–Lindzen–Plumb model for mean flow reversals in stratified fluids
Authors: Renaud Antoine , Venaille Antoine
Published: May 2020

The Holton–Lindzen–Plumb (HLP) model describes the spontaneous emergence of mean flow reversals in stratified fluids. It has played a central role in understanding the Quasi‐Biennial Oscillation of equatorial winds in Earth's stratosphere and has arguably become a linchpin of wave–mean flow interaction theory in geophysical and astrophysical fluid dynamics. The derivation of the model's equation from primary equations follows from several assumptions, including quasi‐linear approximations, WKB expansion of the wavefield, simplifications of boundary‐layer terms, among others. Starting from the two‐dimensional, non‐rotating, Boussinesq equations, we present in this paper a self‐consistent derivation of the HLP model and show the existence of a distinguished limit for which all approximations remains valid. We furthermore discuss the important role of boundary conditions, and the relevance of this model to describe secondary bifurcations associated with a quasi‐periodic route to chaos.
Texture‐based classification of high‐resolution precipitation forecasts with machine‐learning methods
Authors: Hamidi Yamina , Raynaud Laure , Rottner Lucie , Arbogast Philippe
Published: May 2020

Object‐based methods are commonly used for verification and postprocessing of high‐resolution precipitation forecasts. They usually detect objects based on intensity criteria only, without considering the spatial organization of rainfall, known as texture. This article evaluates the performance of several machine‐learning methods to detect “continuous” and “intermittent” rainfall patterns in the forecasts of the French convective‐scale Arome model. A sliding‐window segmentation algorithm, which applies a classification model at each grid point, is implemented. Several classifiers and input textural features are compared. Overall, intermittent precipitation is the most difficult to detect. The random forest classifier is shown to provide the best classification results independently of the predictor used, with a surprising ability to extract a relevant signal from a synthetic descriptor such as the rainfall cumulative distribution function, as well as from the large amount of unprocessed information provided by neighbouring grid points. On the other hand, the logistic regression classifier needs a texture‐oriented predictor, such as the statistics derived from the grey‐level co‐occurrence matrix, to perform well. Global insight into model behaviour is then obtained by examining the importance of input features. Finally, we show that random forests trained on Arome deterministic forecasts can be applied successfully to discriminate between precipitation textures in different Arome configuration outputs and gridded observations.
Rapid and direct identification of the origin of white tea with proton transfer reaction time‐of‐flight mass spectrometry
Authors: Zhang Dandan , Wu Weihua , Qiu Xiaohong , Li Xiaojing , Zhao Feng , Ye Naixing
Published: May 2020

Rationale

White tea has become very popular in recent years, but there has been no scientific identification of white tea from different origins. For product authentication and valorization, every kind of white tea must be marked with an indication of its origin.

Methods

Volatile profiles of white tea leaf samples from their main origins in China (Fuding City, Zhenghe City and Jianyang City) were analyzed using proton transfer reaction time‐of‐flight mass spectrometry (PTR‐TOFMS). Tentative identifications of the volatile organic compounds (VOCs) were obtained by PTR‐TOFMS of the headspace. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS‐DA) were performed to evaluate the differences among the various origins.

Results

Teas from different origins were shown to have characteristic VOCs and profiles. Thus, white teas from different origins could be separated by characterizing the volatile emissions from the dry tea leaves. The ability of the two classification models to use the volatile fingerprints in origin discrimination was investigated.

Conclusions

Two classification models (PCA and OPLS‐DA) were applied to the PTR‐TOFMS data obtained from the VOCs of various white teas. The classification models were shown to be useful in identifying the origin of white tea samples, providing a reference for white tea identification.
A Facile Regioselectively Synthesis of 2‐Alkenylbenzo[1,2‐b:4,5‐b’]dithiophene by Pd/Cu/Ag‐Catalyzed C‐H Functionalization
Authors: Dung Tran Ngoc , Van Trang Nguyen , Thanh Dinh Thi Mai , Van Khanh Nguyen Thi , Nguyen Hien , Nguyen Hue Minh Thi
Published: May 2020

In this work, several alkenylated benzo[1,2‐b:4,5‐b′]dithiophene were synthesized by Pd‐catalyzed C−H functionalization of benzo[1,2‐b:4,5‐b′]dithiophene with various alkenes. This direct alkenylation took place regioselectively at the C‐2 position of the fused heterocycle. The obtained compounds were structurally characterized by NMR and MS spectroscopic methods. Moreover, DFT calculations have been employed to shed light on the regioselectivity of the reaction as well as on the geometry and electronic properties of the newly formed C=C double bonds.
Current Advances of Hollow Capsules as Controlled Drug Delivery Systems
Authors: Quang Tran Huy , Bhave Mrinal , Yu Aimin
Published: May 2020

Polymeric hollow capsules have attracted increasing interest for the development of controlled drug delivery systems due to their capacities to load high amount of drugs and be able to finely tune the drug release profile. Various methods and strategies for capsule preparation and drug loading have been developed over time. Besides that, the controlled drug release from hollow capsules upon external and internal triggers is of great interest and has been a research focus in this area. This article aims to give the most recent progress review on hollow capsule based controlled drug delivery systems with a highlight on strategies being used for drug loading and stimuli‐release. In detail, the fabrication of hollow capsules using template‐assisted or template‐free methods will be introduced first. This will be followed by current strategies for pre‐loading and post‐loading of therapeutic agents into capsules. The article will then be particularly focused on discussing diverse drug‐release systems corresponding to various stimuli conditions including temperature, pH, ultrasound, light irradiation and enzyme degradation.
Synthesis of γ‐Spirolactams from Blaise Reaction Intermediates and 1,2‐Dicarbonyl Compounds
Authors: Liu Jin , Shi Guang , Chen Zhiwei
Published: May 2020

A intermolecular nucleophilic addition/pinacol rearrangement cascade reaction of 1,2‐dicarbonyl compounds and Blaise reaction intermediates has been developed. This highly efficient transformation enables the quick construction of γ‐spiro lactams in a single operation with moderate to good yields as well as mild reaction condition.
Recent Advances in Homogeneous and Heterogeneous Catalyst in Biginelli Reaction from 2015‐19: A Concise Review
Authors: Chopda Lakha V. , Dave Pragnesh N.
Published: May 2020

In the chemistry world, the year 1891 was considered as milestone year for the discovery of new type of heterocyclic compounds by Pietro Biginelli. The Biginelli protocol provides 3,4‐dihydropyrimidin‐2(1H)‐ones/thiones in the presence of Bronsted acids and Lewis acids. Multifunctional Dihydropyrimidones (DHPMs) are displayed wide medicinal properties. Several of homogeneous and heterogeneous catalysts have been reported to improve the yield of product. This review includes the progress of ionic liquids, combination of ionic liquids with homogeneous & heterogeneous catalyst, homogeneous, heterogeneous and asymmetric catalyst took place in last five year (2015–2019) for Biginelli reaction. Most of catalysts showed good catalytic activity (more than 80 %) towards the synthesis of Biginelli adducts.
Effect of Cobalt Phthalocyanine on the Chemical Polymerization of Aniline
Authors: Andriianova Anastasia N. , Abyalilova Aigul R. , Biglova Yulia N. , Mustafin Akhat G.
Published: May 2020

The synthesis of polyaniline (PANI) using organic metal complexes, for example, cobalt phthalocyanine (CoPc), is currently one of the promising approaches for PANI modification. Compounds of this kind favor the improvement of the properties of the target material and participate in the oxidative polymerization of aniline as catalysts. To fully understand the effect of CoPc on the synthesis and properties of PANI, the oxidative polymerization of aniline was monitored by measuring the open‐circuit potential (OCP) and pH, as well as by UV spectroscopy. Combining these techniques allows one to estimate the effect of the catalyst and assume the likely scheme of aniline oxidative polymerization with participation of the catalyst, as well as determine the extent of process acceleration.
Anthraimidazoledione Derivatives in Fluoride Sensing Ensuing Si‐O Bond Cleavage in Organic and Aqueous Medium
Authors: Mondal Subhendu , Roy Saswati Ghosh , Ghosh Kumaresh
Published: May 2020

Anthraimidazoledione derivatives 1 and 2 containing silyl groups have been synthesized and characterized. Anion binding properties with reference to Si−O bond cleavage are documented in organic and aqueous medium. Both compounds 1 and 2 selectively sense F− ion over a series of other anions by exhibiting ratiometric change in UV‐vis spectra in CH3CN. In fluorescence, significant quenching of emission of both 1 and 2 occurs in presence of F−. Other anions in this event are silent. Compounds are also found working in aqueous CH3CN. Both show quenching of emission while aqueous solution of KF is added to their acetonitrile solutions. Importantly, Si−O bond cleavage in 1 and 2 follows first order kinetics and the cleavage is more facile in 1 than 2. The detection limits for fluoride with compounds 1 and 2 were found to be 49.6 μM and 20.1 μM, respectively.
Improving the Interfacial Adhesion of Carbon Fiber/Polyether Ether Ketone Composites by Polyimide Coating
Authors: Wang Tao , Jiao Yongsheng , Mi Zhiming , Wang Chunbo , Wang Daming , Zhao Xiaogang , Zhou Hongwei , Chen Chunhai
Published: May 2020

Polyimide (PI) as a sizing agent for short carbon fiber (SCF) was explored, and a series of SCF‐reinforced polyether ether ketone (PEEK) composites with PI sizing concentrations varying from 0 to 2.0 wt % were fabricated using the extrusion and injection molding techniques. It was found that the PI sizing layer forms homogeneously and compact on the SCF surfaces, and when the PI sizing concentrations was 1.0 wt %, the tensile strength and flexural strength of the corresponding SCF/PEEK composite was significantly increased by 16.8 % and 8.2 % respectively in comparison with the untrelated case. Additionally, dynamic mechanical analysis (DMA) curves demonstrated that storage modulus of SCF/PEEK composites were enhanced with the increasing concentration of PI sizing, resulting the higher stiffness and the lower damping behavior of the composites. Further, the single fiber pull‐out testing was also measured, with the increased interfacial shear strength (IFSS) of CF/PEEK composites by 24.8 % from 70.6 to 88.1 MPa for the CF modified with 1.0 wt % PI sizing, which illustrated that PI sizing can improve fiber surface wettability and interfacial adhesion between CF and PEEK.
Synthesis of 4,4‐Disubstituted 1,2‐Thiazinane‐5‐one 1,1‐Dioxides via the CSIC[≠]Reaction Strategy
Authors: Dyachenko Maksim S. , Kochetkov Artem O. , Dobrydnev Alexey V. , Milokhov Demyd S. , Shishkina Svitlana V. , Konovalova Irina S. , Omelchenko Irina V. , Volovenko Yulian M.
Published: May 2020

A series ofsp3‐enriched 2,2‐disubstituted 1,2‐thiazinane‐5‐one 1,1‐dioxides (including spirocyclic derivatives) has been synthesized through the CSIC [Carbanion mediated Sulfonate (Sulfonamido) Intramolecular Cyclization] reaction strategy. In particular, 2,2‐disubstituted alkyl 3‐aminopropanoates were subsequently sulfonylated with mesyl chloride followed by alkylation with methyl iodide to give the key precursor 2,2‐disubstituted methyl 3‐(methylsulfonamido)propanoates. The latter were treated with sodium hydride and underwent the intramolecular sulfa‐Dieckmann cyclization yielding the target 4,4‐disubstituted 1,2‐thiazinane‐5‐one 1,1‐dioxides (so‐called β‐keto‐δ‐sultams). The structure of the target compounds was confirmed by an X‐ray diffraction study.
NiCo2O4/C Core‐Shell Nanoneedles on Ni Foam for All‐Solid‐State Asymmetric Supercapacitors
Authors: Li Yaoyin , Wang Qiyuan , Shao Jian , Li Kang , Zhao Weiwei
Published: May 2020

Herein, NiCo2O4/C core‐shell nanoneedles grown on Ni foam are prepared by a simple route and applied in supercapacitors. Electrochemical results show that the area specific capacitance of NiCo2O4/C reaches 2057 mF/cm2 at 1 mA/cm2, which is about 4 times than that of the pristine NiCo2O4. The electrode exhibits excellent rate capability (92 % of capacitance retention at 10 mA/cm2) and remarkable cycling stability (81 % of capacitance retention after 10000 cycles). The as‐fabricated all‐solid‐state asymmetric supercapacitor (NiCo2O4/C//AC(active carbon)) achieves an energy density of 2 mW h cm−3 at a power density of 37 mW cm−3 and remains 1.6 mW h cm−3 at a power density of 120 mW cm−3. Moreover, the ASC device can retain 87 % capacitance after 4000 cycles. The result reveals that it is a feasible method to achieve excellent performance in energy storage devices by the dipping method.
All‐Inorganic CsPbI2Br Perovskite Solar Cell with Open‐Circuit Voltage over 1.3 V by Balancing Electron and Hole Transport
Authors: Liu Chong , He Jiajun , Wu Miao , Wu Yuanchuang , Du Pengcheng , Fan Limin , Zhang Qin , Wang Duofa , Zhang Tianjin
Published: May 2020

The energy loss of all‐inorganic metal halide perovskite solar cells is large, which reduces the open‐circuit voltage and photoelectron conversion efficiency of the device. Herein, it is found that the cathode electron transfer speed is much lower than the anode hole transfer speed in CsPbI2Br perovskite solar cell with fluorine‐doped tin oxide (FTO) glass/SnO2/CsPbI2Br/carbon structure, which induces charge accumulation at the cathode and energy loss of the device accordingly. By introducing a new conductive polymer additive polyaniline (PANI) to the CsPbI2Br film, the electron transfer speed at the cathode is enhanced, resulting in balanced charge transfer at both electrodes and reduced energy loss of the device. Ultraviolet photoelectron spectroscopy measurement reveals that the PANI pushes the conduction band minimum of CsPbI2Br upward, leading to stronger driving force for electron extraction. Therefore, the nonradiative recombination at the SnO2/CsPbI2Br interface is greatly suppressed. In addition, PANI can also effectively passivate defects and promote the crystal quality of CsPbI2Br, leading to reduced nonradiative recombination in perovskite materials. Accordingly, the optimized all‐inorganic CsPbI2Br solar cell delivers a high Voc of 1.33 V and power conversion efficiency (PCE) of 13.52%.
Electron Transport Materials: Evolution and Case Study for High‐Efficiency Perovskite Solar Cells
Authors: Elseman Ahmed Mourtada , Xu Cunyun , Yao Yanging , Elisabeth Mbeng , Niu Lianbin , Malavasi Lorenzo , Song Qun Liang
Published: May 2020

The presence of the electron transport layer (ETL) in perovskite solar cells (PSCs) is critical due to the requirement of enhancing the electron collection selectivity. ETLs are essential for achieving a high open‐circuit voltage (VOC), high fill factor (FF), better transport of directional charges, better absorption of incoming light, and thermodynamically competent operation of photogenerated carrier populations. ETLs are sorted as organic, inorganic, or mixed, with different stability, cost effect, and directional charge transport ability. For instance, by using metal oxides as ETLs, power conversion efficiencies (PCEs) higher than 23% are reached for PSCs. Despite the advantages of metal oxide–ETLs and other organic or mixed ETLs, some questions still have to be addressed to achieve better PCEs, like how to passivate or eliminate the surface traps, how to upgrade the comprehension of the heterointerface, and optimization of morphology. Herein, different considerations of ETLs in different physical and environmental conditions, and different deposition methods used, are presented. Finally, the current studies and future challenges are analyzed in the domain of highly efficient PSCs with various ETLs.
Isothermal Precipitation Behavior of Vanadium Carbonitride in V‐, N‐Added Low‐Carbon Steel
Authors: Yang Yong , Zhang Xiao Feng , Li Yan Mei , Huang Zhen Yi
Published: May 2020

Herein, the isothermal precipitation behaviors of V(C,N) in ferrite are studied. At 700 °C, the dominant precipitation behavior of V(C,N) is interphase precipitation (IP), whereas at 660 and 620 °C, random precipitation (RP) is dominant. Both IP and RP show the Nishiyama–Wassermann orientation relationship (OR) with ferrite, unlike the common OR between precipitation and ferrite. The size of most precipitated particles varies in the ranges of 5–8 nm at 660 °C and 3–5 nm at 620 °C. The average values of hardness of ferrite grain formed at 700, 660, and 620 °C are 195.1, 237.6, and 278.6 HV, respectively.
Competitive Oxidation of O2 and CO2 in Fe–C Melts Using Isotope Tracing Method
Authors: Fan Yuewen , Hu Xiaojun , Zhu Rong , Chou Kuochih
Published: May 2020

The application of an O2–CO2 mixture gas in the steel industry makes an important contribution to energy savings and emissions reduction. To clarify the reaction mechanisms of this gas mixture, isotope gases (18O2 and 13CO2) are used to study the competitive oxidation of O2 and CO2, for Fe–C melts at 1873 K. Changes in gas mix composition during the decarburization of Fe–C melts with O2–CO2 are monitored using an online mass spectrometer. The results show that when the O2/CO2 ratio at the inlet is 4:1, the O2 oxidation rate is approximately four times that of CO2. O2 and CO2 decarburization abilities are found to be basically the same, even when the O2 supply is more than sufficient. As for the ability to oxidize Fe in molten steel, when the ratio of O2/CO2 at the inlet is 4:1, the O2 oxidation rate is approximately seven times that of CO2, allowing us to conclude that CO2 is less able to compete with molten iron oxide.
A numerical algorithm for multiple cracks propagation in concrete structure
Authors: Wen Ming , Fang Qian , Zhang Dingli , Fang Huangcheng
Published: May 2020

Multiple cracks are extremely common in aged or partially damaged concrete structures. These cracks have a decisive influence on the safety of structures. In this study, a novel multiple‐crack‐length‐controlled method is presented for analyzing the cracking behavior of multiple cracks in concrete structures. This method introduces topological variables into the finite element calculation to identify the correct crack propagation pattern of multiple‐crack problems. The values of topological variables that are used to active and inactive cracks are continually updated by the maximum stress criterion during calculation. The mathematical formulation of the proposed method is constructed in the incremental form. Thus, it is easy to be implemented in the nonlinear problems and capable of considering the influences of stress history on the plastic behaviors. Furthermore, several numerical examples with different cracking modes are studied. The results show that the proposed method provides a robust, effective, and fast way to solve the multiple‐crack problems in concrete.
Performance assessment of reinforced concrete columns under vehicle impact load using P‐I diagram
Authors: Ma Haiying , Cao Zhen , Shi Xuefei , Hu Ke , Zhou Junyong
Published: May 2020

P‐I diagrams are widely used for structures subjected to blast loads. In the same manner, structures subjected to vehicle impact load, such as bridge columns, could potentially take advantages of the P‐I diagram if the dynamic characteristics of vehicle impact load and bridge columns are well considered. In the paper, the performance of bridge columns and hence the use of P‐I diagram is evaluated under vehicle impact load. The main tasks of the paper are (1) to determine the dynamic characteristics of vehicle impact load through finite element method, and three simplified load shapes are obtained including isosceles triangle, right triangle, and rectangular shapes; (2) to investigate structural failure modes under various shear‐bending ratios and impact loads; (3) to establish the damage index based on the residual axial capacity of bridge columns and to obtain P‐I diagrams at different damage levels of bridge columns under vehicle impact load; (4) to parametrically analyze the effects on the impulse asymptotic and the peak load asymptotic of P‐I diagrams, including column diameter, stirrup reinforcement ratio, longitudinal reinforcement ratio, and strength of the concrete. Finally, a simplified calculation method of P‐I diagrams is proposed to evaluate the performance of bridge columns under vehicle impact load.
Multiscale Investigation of Water Chemistry Effects on Fish Guild Species Richness in Regulated and Nonregulated Rivers of India's Western Ghats: Implications for Restoration
Authors: Atkore Vidyadhar , Kelkar Nachiket , Badiger Shrinivas , Shanker Kartik , Krishnaswamy Jagdish
Published: May 2020

Tropical rivers across the world are experiencing rapid degradation and loss of fish species due to flow regulation, pollution, and other anthropogenic pressures. Knowledge of how flow alterations at different scales affect tropical fish diversity remains limited, especially in terms of how resulting changes in water chemistry affect fish communities. We investigated fish guild composition and responses of guild richness to water chemistry in 120 river segments with and without local‐scale water removals and pollution. This included two regulated subbasins (with flow regulation by barrages and large‐scale water diversions) and two nonregulated subbasins (flows not regulated by these barriers) in India's Western Ghats. Using multivariate ordination and regression models, we identified covariates related to water chemistry and environmental characteristics that explained differences in fish species composition and species richness of three water column position‐based fish guilds in the study area. At the subbasin scale, effects of water chemistry were stronger for individual river segments. At the segment scale, no differences in water chemistry were found between segments with and without water removals or pollution in both regulated and nonregulated subbasins. Guild‐wise species richness, especially of surface‐dwelling fishes, was positively correlated with water temperature and total dissolved solids across regulated and nonregulated subbasins. In regulated subbasins, total alkalinity was positively correlated with species richness of bottom‐dwelling and mid‐column‐dwelling fishes. Landscape‐scale flow alterations and degree of flow regulation by river barriers significantly influenced fish composition and species richness over and above local water withdrawal or pollution. River restoration at both the local (segment) and landscape (basin) scales is crucial for fish conservation. To sustain fish guild diversity, maintenance of ecological flow regimes downstream of barriers needs to receive priority over mitigating local disturbances in regulated river catchments of the Western Ghats.
Danshen (Salvia miltiorhiza) inhibits Leu27 IGF‐II‐induced hypertrophy in H9c2 cells
Authors: Ho Tsung‐Jung , Wu Hsi Chin , Bharath Kumar V. , Kuo Wei‐Wen , Weng Yueh‐Shan , Yeh Yu‐Lan , Mahalakshmi B. , Day Cecilia Hsuan , Li Chi‐Cheng , Huang Chih‐Yang
Published: May 2020

In this study, we used ICI 182 780 (ICI), an estrogen receptor (ER) antagonist, to investigate the estrogenic activity of Danshen, and to further explored whether Danshen extract can block Leu27IGF‐II‐induced hypertrophy in H9c2 cardiomyoblast cells. We first used an IGF‐II analog Leu27IGF‐II, which specifically activates IGF2R signaling cascades and induces H9c2 cardiomyoblast cell hypertrophy. However, Danshen extract completely inhibited Leu27IGF‐II‐induced cell size increase, ANP and BNP hypertrophic marker expression, and IGF2R induction. We also observed that Danshen extract inhibited calcineurin protein expression and NFAT3 nuclear translocation, leading to suppression of Leu27IGF‐II‐induced cardiac hypertrophy. Moreover, the anti‐Leu27IGF‐II‐IGF2R signaling effect of Danshen was totally reversed by ICI, which suggest the cardio protective effect of Danshen is mediated through estrogen receptors. Our study suggests that, Danshen exerts estrogenic activity, and thus, it could be used as a selective ER modulator in IGFIIR induced hypertrophy model.
A laryngeal inflammatory polyp in a miniature dachshund
Authors: Sugimoto Keisuke , Kanda Teppei , Mitsui Ikki , Miyabe Masahiro , Maeta Noritaka
Published: May 2020

A 15‐year old, female miniature dachshund was presented for a 5‐year history of progressive dyspnoea. A laryngeal mass was detected on cervical radiographs. Surgery was performed 5 days later to reduce the volume of the mass and to obtain biopsy samples; the dyspnoea improved. Based on the histopathological findings, the mass was diagnosed as inflammatory polyp. This case of inflammatory polyp in the larynx suggests that it should be listed in the differential diagnoses for laryngeal masses in dogs and that surgical treatment may be curative.
Comparison of evapotranspiration estimates using the water balance and the eddy covariance methods
Authors: Denager Tanja , Looms Majken C. , Sonnenborg Torben O. , Jensen Karsten H.
Published: May 2020

The eddy covariance method estimates the energy flux of latent heat for evapotranspiration. However, imbalance between the land surface energy output and input is a well‐known fact. Energy balance closure is most commonly not achieved, and therefore the eddy covariance method potentially underestimates actual evapotranspiration. Notwithstanding, the method is one of the most established measurement techniques for estimating evapotranspiration. Here, evapotranspiration from eddy covariance (ETEC) is cross‐checked with evapotranspiration calculated as the residual of the water balance (ETwb). The water balance closure using ETEC is simultaneously validated. Over a 6‐yr period, all major terms of the water balance are measured including precipitation, recharge from percolation lysimeters, and soil moisture content from a cosmic‐ray neutron sensor, a capacitance sensor network, and time domain reflectometry (TDR), respectively. In addition, we estimate their respective uncertainties. The study demonstrates that both monthly and yearly ETEC and ETwb compare well and that the water balance is closed when ETEC is used. Concurrently, incoming available energy (net radiation minus ground heat flux) on average exceeds the turbulent energy fluxes (latent heat flux and sensible heat flux) by 31%, exposing the energy–surface imbalance. Consequently, the imbalance in the energy balance using the eddy covariance method must, to a lesser degree, be caused by errors in the latent heat estimates but can mainly be attributed to errors in the other energy flux components.
Hydrogen bond design principles
Authors: Karas Lucas J. , Wu Chia‐Hua , Das Ranjita , Wu Judy I‐Chia
Published: May 2020

Hydrogen bonding principles are at the core of supramolecular design. This overview features a discussion relating molecular structure to hydrogen bond strengths, highlighting the following electronic effects on hydrogen bonding: electronegativity, steric effects, electrostatic effects, π‐conjugation, and network cooperativity. Historical developments, along with experimental and computational efforts, leading up to the birth of the hydrogen bond concept, the discovery of nonclassical hydrogen bonds (CH…O, OH…π, dihydrogen bonding), and the proposal of hydrogen bond design principles (e.g., secondary electrostatic interactions, resonance‐assisted hydrogen bonding, and aromaticity effects) are outlined. Applications of hydrogen bond design principles are presented.

This article is categorized under:

Structure and Mechanism > Molecular Structures

Structure and Mechanism > Reaction Mechanisms and Catalysis
α′-cosmology: solutions and stability analysis
Authors: Bernardo Heliudson , Franzmann Guilherme
Published: May 2020

Abstract

We review O(d, d) Covariant String Cosmology to all orders in α′ in the presence of matter and study its solutions. We show that the perturbative analysis for a constant dilaton in the absence of a dilatonic charge does not lead to a time-independet equation of state. Meanwhile, the non-perturbative equations of motion allow de Sitter solutions in the String frame parametrized by the equation of state and the dilatonic charge. Among this set of solutions, we show that a cosmological constant equation of state implies a de Sitter solution both in String and Einstein frames while a winding equation of state implies a de Sitter solution in the former and a static phase in the latter. We also consider the stability of these solutions under homogeneous linear perturbations and show that they are not unstable, therefore defining viable cosmological scenarios.
Diffractive dijet photoproduction at the EIC
Authors: Guzey Vadim , Klasen Michael
Published: May 2020

Abstrac

We present a first, detailed study of diffractive dijet photoproduction at the recently approved electron-ion collider (EIC) at BNL. Apart from establishing the kinematic reaches for various beam types, energies and kinematic cuts, we make precise predictions at next-to-leading order (NLO) of QCD in the most important kinematic variables. We show that the EIC will provide new and more precise information on the diffractive parton density functions (PDFs) in the pomeron than previously obtained at HERA, illuminate the still disputed mechanism of global vs. only resolved-photon factorization breaking, and provide access to a completely new quantity, i.e. nuclear diffractive PDFs.
Presentation of a novel real-time production supply concept with cyber-physical systems and efficiency validation by process status indicators
Authors: Bayhan Haci , Meißner Matthias , Kaiser Pascal , Meyer Maria , Hompel Michael ten
Published: May 2020

Industry 4.0, digitization, and Internet of Things enable companies to react quickly and flexibly to market changes. The objective is the production of customized products at the cost of a mass-produced product. The widespread entry of cyber-physical systems enables a networking of all entities. The introduction of cyber-physical systems in production and logistic systems dissolves existing rigid structures and as a result versatile cyber-physical production systems occur. To support the flexibility of the cyber-physical production systems, the production supply needs to be adapted. For this reason, this paper proposes a novel universal production supply concept. This concept introduces a decentralized controlled supply. It is executed by several cyber-physical system entities, which are represented by software agents. These agents negotiate autonomously with each other. The novel concept was implemented in a research lab and evaluated quantitatively and qualitatively. For the quantitative evaluation, the efficiency of the novel concept is evaluated and compared with a kanban supply. An innovative key performance indicator system called process status indicators evaluates the efficiency. The result of this indicator system states that the novel concept is more efficient than the kanban supply.
Effect of print orientation and bronze existence on tribological and mechanical properties of 3D-printed bronze/PLA composite
Authors: Hanon Muammel M. , Alshammas Yazan , Zsidai László
Published: May 2020

In this work, fused deposition modeling (FDM) technology is employed for manufacturing tribological and tensile testing specimens. The test pieces are fabricated in diverse directions to examine the influence of print orientation. The tribological tests are carried out in reciprocating sliding and under dry condition. Due to their relevance, the surface roughness and the hardness of the products are studied as well. Many images are captured under a microscope to better understand the surface morphology of 3D-printed parts before and after testing. The findings reveal that the existence of various print orientations determines differences in mechanical properties and tribological behavior. Among the investigated parameters, the one with the highest tensile strength at break point is the On-Edge print orientation. The vertically oriented test pieces offer the highest friction tendency but the lowest wear depth. Meanwhile, less wear is observed when sliding under low loads but the tendency for stick-slip phenomenon occurrence increases. Although PLA is presently one of the most popular filaments for 3D printing, it can be employed in some industrial applications (e.g., bushings and bearings), if the tribological properties are amended. Bronze is characterized by excellent sliding capability because of its very low metal-on-metal friction. To date, very limited attention has been given to research on the tribology of 3D-printed objects. Therefore, the purpose of the current work is to fill the gap in knowledge by being the first study to evaluate the impact of bronze presence and 3D printing orientation on the tribological properties of bronze/PLA composite.