bluuebunny/crossref_metadata_2025 huggingface dataset:
Ruthenium‐Catalyzed Three‐Component Alkylation: A Tandem Approach to the Synthesis of Nonsymmetric N,N‐Dialkyl Acyl Hydrazides with Alcohols
Authors: Bettoni Léo , Joly Nicolas , Lohier Jean‐François , Gaillard Sylvain , Poater Albert , Renaud Jean‐Luc
Published: June 2021

The borrowing hydrogen strategy has been applied in the synthesis of nonsymmetric N,N‐dialkylated acyl hydrazides via a tandem three‐component reaction catalyzed by a phosphine free diaminocyclopentadienone ruthenium tricarbonyl complex. This strategy represents the first direct one‐pot approach to nonsymmetric functionalized acyl hydrazides. Different aromatic acyl hydrazides underwent dialkylation with a variety of primary or secondary alcohols and methanol or ethanol as alkylating agents in mild reaction conditions and good yields. Deuterium labelling experiments suggested that the primary or secondary alcohol was the hydrogen source in this tandem process. DFT calculations show that the combination of the tandem mixed product cannot be perfectly explained neither structurally nor electronically, but might be dependent of the physical state of the aldehyde or ketone intermediate (gaz vs. liquid) at the reaction temperature.

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Elucidating the Role of Water‐Related Traps in the Operation of Polymer Field‐Effect Transistors
Authors: Iqbal Hamna F. , Waldrip Matthew , Chen Hu , McCulloch Iain , Jurchescu Oana D.
Published: June 2021

Conjugated polymers have gained momentum as serious contenders for next‐generation flexible electronics, but their susceptibility to water represents a major problem. Atmospheric water is ubiquitous and its inadvertent diffusion into polymeric devices generates charge carrier traps, reducing their performance and stability. A good understanding of the physical processes associated with the presence of water is therefore necessary in order to be able to suppress the related trapping events and enable stable, high‐performance devices. Here, evidence is shown that water introduces traps in the bandgap of organic semiconductors and the impact of these traps on the electrical properties of polymer organic field‐effect transistors (OFETs) based on indacenodithiophene‐co‐benzothiadiazole (IDT‐BT) is investigated. Monitoring device parameters and the trap density of states (t‐DOS) during moisture extrication reveals the existence of two types of water‐related traps: shallow traps originating from water inhabiting the voids of the polymer film and deeper traps arising from chemisorbed water present at the dielectric/polymer interface. A trap passivation method based on flame‐annealing is introduced to eliminate the interfacial traps. As a result, stable OFETs, with threshold voltage shifts less than ΔVth = −0.3 V and constant mobilities (<10% variation) after three months of storage, are fabricated.
In‐Depth Analysis of the Degradation Mechanisms of High‐Nickel, Low/No‐Cobalt Layered Oxide Cathodes for Lithium‐Ion Batteries
Authors: Lee Steven , Li Wangda , Dolocan Andrei , Celio Hugo , Park Hyoju , Warner Jamie H. , Manthiram Arumugam
Published: June 2021

A rational compositional design of high‐nickel, cobalt‐free layered oxide materials for high‐energy and low‐cost lithium‐ion batteries would be expected to further propel the widespread adoption of electric vehicles (EVs), yet a composition with satisfactory electrochemical properties has yet to emerge. The previous work has demonstrated a promising LiNi0.883Mn0.056Al0.061O2 (NMA‐89) composition that outperformed high‐nickel, cobalt‐containing analogs in cycling stability and maintained a comparable rate performance and thermal stability. Herein, the capacity fading mechanism of NMA‐89 in a pouch full cell with a 4.2 V cutoff is compared to that of its cobalt‐containing analogs. The results reveal that particle cracking in LiNi0.89Mn0.055Co0.055O2 (NMC‐89) and LiNi0.883Co0.053Al0.064O2 (NCA‐89) leads to a loss of active material and an increase in surface area, thereby exacerbating structural and surface instabilities, accelerating impedance and polarization growth, and ultimately reducing their capacity retentions. LiNi0.89Mn0.044Co0.042Al0.013Mg0.011O2 (NMCAM‐89) and NMA‐89 experience subdued surface reactions and maintain spherical particle structures, both of which are conducive to their capacity retentions during long‐term cycling. This investigation offers insights into how specific transition‐metal ions dictate the electrochemical stability of high‐Ni layered oxide cathode materials, highlights the benefit of Mn‐Al combination in NMA‐89, and presents potential strategies to further enhance the performance of this novel class of cathode materials.
Quinoline‐Coupled Coumarin‐Based Ruthenium(II) Dye Sensitizer for Photoelectrochemical Cells and Solar Cells: A Mimic for an Artificial‐Light‐Harvesting System
Authors: Athanas Anish Babu , Kalaiyar Swarnalatha
Published: June 2021

The conversion of solar energy into chemical energy by the use of dye‐sensitized solar cells (DSSCs) and dye‐sensitized photoelectrochemical cells (DSPECs) has been considered a convenient method in recent years. Herein, DSPEC and DSSC devices are fabricated by mimicking the function of photosystem II in natural photosynthesis with a new quinoline‐coupled coumarin‐based ruthenium(II) dye (RQC)‐sensitized TiO2 semiconductor as the light‐harvesting center. By using the RQC‐sensitized TiO2 as the working electrode, photoelectrochemical water‐splitting reactions are effectively conducted in a phosphate buffer solution (pH = 6), with 30 mm triethanolamine as the sacrificial electron donor. Oxygen and hydrogen bubbles are evolved from the working electrode and counter electrode, respectively. By applying +0.78 V potential versus a relative hydrogen electrode, an initial photocurrent density of 11.07 mA cm−2 and a final photocurrent density of 9.66 mA cm−2 are achieved. Under this condition, a maximum photoelectrochemical water splitting efficiency of 4.98% is obtained. The photocurrent–voltage (J–V) characterization of the DSSC device fabricated with RQC under standard AM 1.5G illumination furnishes a Jsc of 11.4 mA cm−2, Voc of 0.69 V, fill factor of 0.53, and power conversion efficiency (η) of 4.16%.
Low‐Temperature Protonic Ceramic Fuel Cells through Interfacial Engineering of Nanocrystalline BaCe0.7Zr0.1Y0.1Yb0.1O3−δ Electrolytes
Authors: Gao Jun , Meng Yuqing , Duffy Jack H. , Brinkman Kyle S.
Published: June 2021

Nanocrystalline BaCe0.7Zr0.1Y0.1Yb0.1O3−δ (BCZYYb) is designed by a novel strategy with improved proton transport properties at low temperatures (<300 °C). In situ Raman spectroscopy and electrical conductivity relaxation (ECR) are used to quantitatively evaluate the surface exchange coefficients during the hydrogen isotope exchange process. Similar surface exchange coefficients are measured via in situ Raman spectroscopy and ECR measurements, representing new tools to better understand proton transport behaviors at the materials’ interface. The surface exchange coefficient in nanocrystalline BCZYYb is nearly four times higher than that in conventional dense BCZYYb at 300 °C, indicating higher surface mobility of protonic species in the designed BCZYYb membrane. The improved performance originates from the combined interfacial and bulk effects for proton transport at low temperatures. In addition, low‐temperature protonic ceramic fuel cells (PCFCs) are built based on a nanocrystalline BCZYYb electrolyte with improved single‐cell performance at 300 °C, which indicates enhanced proton transport properties in contemporary energy conversion and storage materials can be achieved through interfacial engineering.
Genetic variability, adaptability and, stability of safflower genotypes developed for the Brazilian conditions by REML/BLUP
Authors: de Oliveira Neto Sebastião Soares , Zeffa Douglas Mariani , Ebertz Odila Friss , Zoz Tiago , Zanotto Maurício Dutra
Published: June 2021

Safflower (Carthamus tinctorius L.) has stood out as an oilseed crop with potential for cultivation in Brazil and can be inserted in the already consolidated production systems. However, obtaining adapted genotypes is essential for crop development, and the study of genetic variability and agronomic performance in different regions contributes to the recommendation of new cultivars. However, the genotype × environment interaction can influence the selection and recommendation of a given genotype for a region of cultivation and hinder the breeder's work. The use of mixed models allows the evaluation of genotype performance without the influence of the genotype × environment interaction, which makes recommending a genotype for a region more accurate. Four experiments were carried out in different regions of Brazil (Bauru‐SP, Botucatu‐SP and, Campo Novo do Parecis‐MT) to evaluate 10 safflower genotypes in the final stage of breeding. The genetic variability of genotypes was analyzed through similarity analysis, as well as the stability and adaptability of genotypes through mixed models. Wide variability was found between the evaluated genotypes. The use of mixed models allowed the identification of safflower genotypes with high stability and adaptability of the grain and oil yield for cultivation in Brazil.
Organic molecular aggregates: From aggregation structure to emission property
Authors: Ma Suqian , Du Sijia , Pan Guocui , Dai Shuting , Xu Bin , Tian Wenjing
Published: June 2021

Organic molecular aggregates have attracted widespread attention over the past decade owing to their unique optoelectronic properties in the aggregate state, which mainly involves the effects of aggregation structure as well as molecular packing mode. Although many examples of H‐ and J‐aggregates defined by molecular exciton model have been found, there are also other types of unconventional aggregates, especially for aggregation‐induced emission (AIE) system. In this review, the recent progress of some examples of basic and novel aggregate forms, as well as coassembled forms, presenting distinctive optical features, such as optical waveguide and polarization emission, polymorph‐dependent emission and stimuli‐responsive luminescence are presented. The systematic insight into the relationship between the aggregation structure and emission property is discussed. Guidelines are therefore anticipated and will direct the future preprogramming molecular design so as to fine‐tune the emission feature through a specific aggregation model for developing organic molecular aggregates with desirable optoelectronic properties.
Multicomponent Dehydrogenative Synthesis of Acridine‐1,8‐diones Catalyzed by Ru‐doped Hydrotalcite
Authors: Sardar Bitan , Jamatia Ramen , Pal Debjyoti , Srimani Dipankar
Published: June 2021

The usage of biomass‐derived chemicals to synthesize pharmaceutically important heterocyclic scaffold via acceptorless dehydrogenation is an emerging trend in chemistry. Herein, we describe the applicability of Ru‐doped hydrotalcite (Ru‐HT) in the dehydrogenative synthesis of structurally important acridine‐1,8‐dione derivatives. To highlight the practical utility, the gram‐scale synthesis of acridine‐1,8‐dione and the successful recyclability of the catalyst were shown.
Beam‐Search zum automatisierten Entwurf und Scoring neuer ROR‐Liganden mithilfe maschineller Intelligenz**
Authors: Moret Michael , Helmstädter Moritz , Grisoni Francesca , Schneider Gisbert , Merk Daniel
Published: June 2021

Chemische Sprachmodelle ermöglichen ein De‐novo‐Wirkstoff‐Design ohne explizite chemische Konstruktionsregeln. Während solche Modelle angewendet wurden, um neuartige Verbindungen mit angestrebter biologischer Aktivität zu generieren, bleibt die tatsächliche Priorisierung und Auswahl der vielversprechendsten Molekülentwürfe (“Designs”) eine Herausforderung. Wir haben hier die von chemischen Sprachmodellen gelernten Wahrscheinlichkeiten mithilfe des Beam‐Search‐Algorithmus als Modell‐intrinsische Technik für das Moleküldesign und die Bewertung der Designs (“Scoring”) genutzt. Die prospektive Anwendung dieser Methode führte zu neuartigen inversen Agonisten der Retinoid‐related‐Orphan‐Rezeptoren (RORs). Jedes Design war in drei Reaktionsschritten synthetisierbar und zeigte eine niedrig‐mikromolare bis nanomolare Potenz gegenüber RORγ. Als Modell‐intrinsische Technik eliminiert das Beam‐Search‐Sampling die strikte Notwendigkeit externer Molekül‐Scoring‐Funktionen und erweitert damit die Anwendbarkeit generativer künstlicher Intelligenz in der datengetriebenen Wirkstoffforschung.
Partial Coordination‐Perturbed Bi‐Copper Sites for Selective Electroreduction of CO2 to Hydrocarbons
Authors: Wang Rui , Liu Jiang , Huang Qing , Dong Long‐Zhang , Li Shun‐Li , Lan Ya‐Qian
Published: June 2021

In the electrochemical CO2 reduction reaction (CO2RR), it is challenging to develop a stable, well‐defined catalyst model system that is able to examine the influence of the synergistic effect between adjacent catalytic active sites on the selective generation of C1 or C2 products. We have designed and synthesized a stable crystalline single‐chain catalyst model system for electrochemical CO2RR, which involves four homomorphic one‐dimensional chain‐like compounds (Cu‐PzH, Cu‐PzCl, Cu‐PzBr, and Cu‐PzI). The main structural difference of these four chains is the substituents of halogen atoms with different electronegativity on the Pz ligands. Consequently, different synergistic effects between bi‐copper centers lead to changes in the faradic efficiency (FE
:FE
). This work provides a simple and stable crystalline single‐chain model system for systematically studying the influence of coordination microenvironment on catalytically active centers in the CO2RR.
Total Synthesis of (+)‐3‐Deoxyfortalpinoid F, (+)‐Fortalpinoid A, and (+)‐Cephinoid H
Authors: Ren Zhiqiang , Sun Zhongliu , Li Yifei , Fan Xin , Dai Mingda , Wang Yunxia , Hu Xiangdong
Published: June 2021

3‐Deoxyfortalpinoid F, fortalpinoid A, and cephinoid H are members of the Cephalotaxus diterpenoids class of natural products, which feature diverse chemical structures and valuable biological activities. We report herein the development of a diastereoselective Pauson–Khand reaction as an effective pathway to access the core tetracyclic skeleton, which is found widely in Cephalotaxus diterpenoids. Furthermore, we enabled the construction of the tropone moiety through a ring‐closing metathesis/elimination protocol. Based on the developed strategy, asymmetric synthesis of the title compounds has been achieved for the first time.
Interfacial tuning and designer morphologies of microporous membranes based on polypropylene/natural rubber nanocomposites
Authors: Bicy Kottathodi , Rouxel Didier , Poncot Marc , Royaud Isabelle , Bourson Patrice , Chapron David , Kalarikkal Nandakumar , Thomas Sabu
Published: June 2021

Microporous polypropylene (PP) nanocomposite membranes are in great demand in various fields such as energy harvesting, water purification, and other industrial applications. Thin films of PP/natural rubber (NR) blend nanocomposite have been prepared by melt mixing and the membranes are made porous by extracting the NR phase from the blend. The present study gives a better insight into the nanoparticle shape and localization‐tailored porous morphology of PP membrane. Thermodynamic prediction of nanofiller localization and its impact on morphology were studied. 2D clay platelets in PP matrix tune the morphology of the porous membrane into lamellar, whereas spherical nanofillers give elongated spherical pores. The localization of nanoparticles was observed using transmission electron microscope, which is also confirmed from theoretical prediction of localization of nanofillers with the help of interfacial energy and surface tension. Thermal studies reveal that nanofillers enhance the thermal stability of polymers. Mechanical studies reveal that nanoparticles improve the mechanical properties of the system. 2D platelet shaped‐nanofillers enhance the mechanical strength of the polymer up to 39%, which is higher than that obtained for 3D spherical nanofillers. Nanofiller shape and localization have a great influence in deciding the properties and porosity of the membrane.
4‐Propargyl‐substituted 1H‐pyrroles induce apoptosis and autophagy via extracellular signal‐regulated signaling pathway in breast cancer
Authors: Atmaca Harika , Ilhan Suleyman , Yilmaz Elif Serel , Zora Metin
Published: June 2021

Novel pyrrole derivatives (PDs) with propargyl units (1–7) were investigated for their anticancer activity on breast cancer cells. The MTT assay was used to assess the cell viability. Morphological changes in human breast cancer cells were visualized under a phase‐contrast microscope. Apoptosis and autophagy were detected using the DNA fragmentation assay and staining by autophagic vacuoles, respectively. The levels of apoptosis‐ and autophagy‐related proteins such as cytochrome c, Bcl‐2, LC3‐I/II were investigated by Western blot analysis. The effect of PDs on the ERK1/2 signaling pathway was investigated using specific inhibitors. All the tested PDs were found to be active in the range of 36.7 ± 0.2 to 459.7 ± 4.2 µM. Compounds 3 and 4 showed cytotoxic activity in breast cancer cells, but were found to be safer with lower cytotoxicity on human nontumorigenic epithelial breast cells. Compound 4 induced apoptosis, whereas compound 3 induced autophagy. Both compounds inhibited the ERK signaling pathway in breast cancer cells. The present study revealed that both synthesized PDs induced different programmed cell death types by inhibiting the ERK signaling pathway in two genotypically different breast cancer cells. Therefore, novel PDs might be promising anticancer agents for breast cancer therapy and further structural modifications of PDs may yield promising anticancer agents.
Anti–Double‐Stranded DNA Antibodies Recognize DNA Presented on HLA Class II Molecules of Systemic Lupus Erythematosus Risk Alleles
Authors: Tsuji Hideaki , Ohmura Koichiro , Jin Hui , Naito Ryota , Arase Noriko , Kohyama Masako , Suenaga Tadahiro , Sakakibara Shuhei , Kochi Yuta , Okada Yukinori , Yamamoto Kazuhiko , Kikutani Hitoshi , Morinobu Akio , Mimori Tsuneyo , Arase Hisashi
Published: June 2021

Objective

Specific HLA class II alleles are associated with susceptibility to systemic lupus erythematosus (SLE). The role of HLA class II molecules in SLE pathogenesis remains unclear, although anti‐DNA antibodies are specific to SLE and correlate with disease activity. We previously demonstrated that misfolded proteins bound to HLA class II molecules are specific targets for the autoantibodies produced in autoimmune diseases. This study was undertaken to validate our hypothesis that DNA binds to HLA class II molecules in a manner similar to that of misfolded proteins and that DNA bound to HLA class II molecules is involved in SLE pathogenesis.

Methods

We analyzed the binding of DNA to HLA class II molecules, as well as the response of cells expressing anti‐DNA B cell receptors (BCRs) to cells expressing the DNA/HLA class II complex.

Results

Efficient binding of DNA to HLA class II molecules was observed in risk alleles of SLE, such as HLA–DRB1*15:01. The efficiency of DNA binding to each HLA–DR allele was positively associated with the risk of SLE conferred by the HLA–DR allele. In addition, reporter cells carrying anti‐DNA BCRs were activated by cells expressing DNA/HLA class II complexes.

Conclusion

These results provide evidence that DNA bound to HLA class II molecules is involved in SLE pathogenesis.
Recent advances in engineering of microbial cell factories for intelligent pH regulation and tolerance
Authors: Gao Xiaopeng , Xu Ke , Ahmad Nadeem , Qin Lei , Li Chun
Published: June 2021

pH regulation is a serious concern in the industrial fermentation process as pH adjustment heavily utilizes acid/base and pollutes the environment. Under pH‐stress conditions, microbial growth and production of valuable target products may be severely affected. Furthermore, some strains generating acidic or alkaline products require self pH regulation and increased tolerance against pH‐stress. For pH control, synthetic biology has provided advanced engineering approaches to construct robust and more intelligent microbial strains, exhibiting tolerance to pH‐stress to cope with limitations of pH regulation. This study reviewed the current progress of advanced strain evolution strategies to engineer pH‐stress tolerant strains via synthetic biology. In addition, a large number of pH‐responsive elements, including promoters, riboswitches, and some proteins have been investigated and applied for construction of pH‐responsive genetic circuits and intelligent pH‐responsive microbial strains.
COVID‐19 cardiac arrest due to Prinzmetal's angina in a previously normal heart
Authors: Wang Melinda , Talon Andrew , Saririan Mehrdad
Published: June 2021

In COVID‐19 patients who develop sudden ST elevations it is necessary to consider cardiac causes other than myocardial infarction, such as coronary vasospasm.
COVID‐19 reinfection in a healthcare worker after exposure with high dose of virus: A case report
Authors: Ahmadian Shahram , Fathizadeh Hadis , Shabestari Khiabani Saeid , Asgharzadeh Mohammad , Kafil Hossein Samadi
Published: June 2021

Reinfection with COVID‐19 is possible after exposure to a high dose of the virus. Due to immunity acquired during the previous infection, light symptoms are expected. The finding indicates importance of continuous protection in healthcare workers.
Successful ixazomib treatment for relapsed and refractory acute myeloid leukemia transformed from myelodysplastic syndrome
Authors: Oka Satoko , Ono Kazuo
Published: June 2021

Elevated NF‐kB levels have been identified in primitive bone marrow cells from patients with MDS/AML, suggesting NF‐kB as a therapeutic target in MDS/AML. We herein describe an MDS patient ineligible for SCT who, following treatment with azacitidine and bortezomib, transformed to leukemia, but maintained complete remission after monotherapy with ixazomib.
Multiple symmetric lipomatosis (Madelung's disease) with symptoms and signs of hypertension, lipodystrophy, and dyspnea: A case report and literature review
Authors: Tsilivigkos Christos , Mastronikolis Stylianos , Lygeros Spyridon , Tsilimpoti Dimitra , Papadas Theodoros
Published: June 2021

Madelung's disease generally refers to a benign symmetrical lipomatosis of the neck, but its presentation can vary. It is treated surgically and different approaches can be implemented. In cases of a threatened airway, a tracheostomy can be performed.
Rhizopus microsporus typhlitis in a patient with acute myelogenous leukemia
Authors: Trybula Marcus , Wang Diping , Baumann Lauren , Pritts Timothy A. , Hambley Bryan C.
Published: June 2021

While patients undergoing treatment for hematologic malignancies are at risk for a variety of infections, gastrointestinal mucormycosis is a rare and feared complication. Diagnosis requires a high index of suspicion and timely evaluation. Prompt treatment improves patient outcomes.
Layered Oxides SrLaFe1‐xCoxO4‐δ (x=0–1) as Bifunctional Electrocatalysts for Water‐Splitting
Authors: Alom Md. Sofiul , Ramezanipour Farshid
Published: June 2021

Multifunctional materials that are capable of facilitating multiple electrocatalytic processes are highly desirable. This work reports the observation of bifunctional electrocatalytic properties for water‐splitting in layered oxides, featuring 2‐dimensional layers of octahedrally coordinated transition metals separated by alkaline‐earth or rare‐earth metals. Remarkably, these materials are able to catalyze both half‐reactions of water‐splitting, i. e., oxygen‐evolution reaction (OER) and hydrogen‐evolution reaction (HER). Electrical charge‐transport studies of SrLaFe1‐xCoxO4‐δ in a wide range of temperatures, 25 to 800 °C, indicate semiconducting behavior for all three compounds, where there is a systematic increase in electrical conductivity as a function of temperature. The end member of the series, SrLaCoO4‐δ, exhibits the highest electrical charge transport and best electrocatalytic activity toward both OER and HER. This catalyst also features the highest degree of polyhedral distortion as well as the presence of oxygen‐vacancies. In addition, the transition metals in this material have a favorable electronic configuration for enhanced electrocatalytic activity.
Oxygen Reduction Reaction at Single‐Site Catalysts: A Combined Electrochemical Scanning Tunnelling Microscopy and DFT Investigation on Iron Octaethylporphyrin Chloride on HOPG**
Authors: Facchin Alessandro , Zerbetto Mirco , Gennaro Armando , Vittadini Andrea , Forrer Daniel , Durante Christian
Published: June 2021

Here, we investigate the electrochemical activity of a highly oriented pyrolytic graphite (HOPG) supported iron octaethylporphyrin chloride film as a working electrode for the oxygen reduction reaction in 0.1 M HClO4 electrolyte. A voltammetric investigation indicated a quasi‐reversible electron transfer for the FeIII/FeII redox process, which turned out to be responsible for a “redox catalysis like” mechanism, in which the reduction of the metal center is first required to allow the O2 reduction. Here we proved that O2 is mostly reduced to H2O in a tetraelectronic process, as evidenced by a rotating ring‐disk electrode (RRDE). Furthermore, electrochemical scanning tunnelling microscopy (EC‐STM) is used as in operando technique for probing the electrode surface at the atomic level while the oxygen reduction reaction occurs, obtaining information on the molecule adlayer electronic and topographic structures. This allows us to follow the change in redox state from FeIII to FeII induced by the change of the electrode potential in O2 saturated electrolyte. The adsorption of O2 at the iron center was visualized and its depletion upon the application of a potential at which O2 can be reduced. The ORR process catalyzed by FeOEP adsorbed on HOPG was modelled by combining density functional theory, molecular dynamics, and thermodynamics data.
Review and Recent Advances of Oxygen Transfer in Li‐air Batteries
Authors: Li Jie , Hou Linfa , Yu Mingfu , Li Qiang , Zhang Tianyu , Sun Hong
Published: June 2021

The development of high performance and low weight energy storage devices has been recently geared towards new energy batteries for electric and hybrid electric vehicles. Li‐air batteries are considered as an emerging energy source for electric cars because of their attractive theoretical specific energy of 11,400 Wh kg−1. Oxygen, as the positive electrode reaction substance of Li‐air battery, predominantly affects the dynamic performance of the battery and its diffusion is an important factor limiting the discharge process. Based on the resistance of oxygen transmission, the characteristics and influence of the Li‐air batteries are reviewed in this paper. The research on oxygen selective membrane, oxygen dissolution and transfer in positive electrode and electrolyte, structure of positive electrode and oxygenated additive in electrolyte are discussed to narrow down the internal mechanism factors that influence the Li‐air battery performance and service life. By discussing pathways to reduce the oxygen transmission resistance and hence improve the performance and life of the battery, we provide future perspectives on the application of Li‐air battery in electric vehicular power systems.
Promotion of Proton Conductivity by Encapsulation of Metal‐Organic Polyhedra in Metal‐Organic Frameworks
Authors: Wang Bin‐Cheng , Feng Zhi‐Ying , Hao Biao‐Biao , Zhang Chen‐Xi , Wang Qing‐Lun
Published: June 2021

A Zr‐based metal‐organic polyhedron (MOP) was self‐assembled in a porous MOF host, DUT‐68, successfully to synthesize MOP‐1@DUT‐68. The MOP guest (MOP‐1) has a diameter of about 20 Å, larger than that of the square windows (pore sizes of ∼14 Å) of DUT‐68 but smaller than that of the rhombicuboctahedral cage (27.7 Å), which means that the migration and leaching of MOP‐1 could be effectively prohibited if MOP‐1 is encapsulated in the MOF′s cavities. The proton conductivity of MOP‐1@DUT‐68 is 1.14×10−3 S cm−1 (at 80 °C under 98 % relative humidity), which is three orders of magnitude higher than that of DUT‐68. Compared with MOP‐1⊂DUT‐68, which was synthesized by impregnation, MOP‐1@DUT‐68 is more prone to form faster proton‐conduction pathways and thus provides higher proton conductivity.
Cytotoxic 7‐Methoxylated Caged Xanthones from the Twigs of Garcinia oligantha
Authors: Yang Jin‐Ling , Fu Wen‐Wei , Xiang Qian , Wu Rong , Tang Yue‐Xun , Zheng Chang‐Wu , Lu Yue , Zhou Hua , Xu Hong‐Xi
Published: June 2021

Main observation and conclusion

Nineteen unprecedented 7‐methoxylated caged xanthones (1—19) were isolated from the twigs of Garcinia oligantha under the guidance of NMR spectroscopy. Their structures and absolute configurations were demonstrated by extensive spectroscopic data, single‐crystal X‐ray diffraction, electronic circular dichroism (ECD) calculations, and the modified Mosher's method. Compound 1 is a rare scalemic 7‐methoxylated neo‐caged xanthone, which was resolved using HPLC with CD detection on a chiral‐phase AD column, and compounds 2—3 are rare 7‐methoxylated caged xanthones with the hydrogenated Δ8(8a) double bond. Fourteen compounds exhibited promising inhibitory activities against four human cancer cell lines with IC50 values ranging from 1.9 to 14.3 μmol/L. A cell apoptosis analysis using flow cytometry showed that compound 11 could induce apoptosis in a dose dependent manner. Moreover, PARP, caspase‐9, and Bcl‐2 western blotting suggested that compound 11‐induced apoptosis may be involved in caspase‐dependent pathway.
Dopant and Current Rate Dependence on the Structural Evolution of P2‐Na2/3Mn0.8Zn0.1M0.1O2 (M=Cu, Ti): An Operando Study
Authors: Stansby Jennifer H. , Sharma Neeraj , Avdeev Maxim , Brand Helen E. A. , Gonzalo Elena , Drewett Nicholas E. , Ortiz‐Vitoriano Nagore , Rojo Teófilo
Published: June 2021

Variable current rate operando XRD experiments were performed on the P2‐ Na2/3Mn0.8Zn0.1Cu0.1O2 composition, which displays promising electrochemical properties. The data reveals the reversible formation of a new and previously undetected ordering reflection upon extraction of Na‐ions, and that small compositional alterations may dramatically impact structural evolution and electrochemical properties. For P2‐ Na2/3Mn0.8Zn0.1Cu0.1O2 at all current rates examined (25, 50 and 100 mA.g−1), comparable structural evolution on charge is observed, but the structural evolution on discharge is shown to be significantly influenced by the current applied during the preceding charge step. For both P2‐ Na2/3Mn0.8Zn0.1Cu0.1O2 and P2‐ Na2/3Mn0.8Zn0.1Ti0.1O2 comparable structural evolution is observed only at a slower current rate of 25 mA.g−1. Overall, the structural evolution of these layered materials is shown to be dependent on the cycling history, highlighting the significance of applied current rate during cycling, especially during the initial cycle.
Patient‐reported symptom burden in routine oncology care: Examining racial and ethnic disparities
Authors: Bulls Hailey W. , Chang Pi‐Hua , Brownstein Naomi C. , Zhou Jun‐Min , Hoogland Aasha I. , Gonzalez Brian D. , Johnstone Peter , Jim Heather S. L.
Published: June 2021

Background

Racial and ethnic disparities are well‐documented in cancer outcomes such as disease progression and survival, but less is known regarding potential disparities in symptom burden.

Aims

The goal of this retrospective study was to examine differences in symptom burden by race and ethnicity in a large sample of cancer patients. We hypothesized that racial and ethnic minority patients would report greater symptom burden than non‐Hispanic and White patients.

Methods and results

A total of 5798 cancer patients completed the Edmonton Symptom Assessment Scale—revised (ESAS‐r‐CSS) at least once as part of clinical care. Two indicators of symptom burden were evaluated: (1) total ESAS‐r‐CSS score (i.e., overall symptom burden) and (2) number of severe symptoms (i.e., severe symptomatology). For patients completing the ESAS‐r‐CSS on multiple occasions, the highest score for each indicator was used. Zero‐inflated negative binomial regression analyses were conducted, adjusting for other sociodemographic and clinical characteristics. Symptomology varied across race. Patients who self‐identified as Black reported higher symptom burden (p = .016) and were more likely to report severe symptoms (p < .001) than self‐identified White patients. Patients with “other” race were also more likely to report severe symptoms than White patients (p = .032), but reported similar total symptom burden (p = .315). Asian and Hispanic patients did not differ from White or non‐Hispanic patients on symptom burden (ps > .05).

Conclusion

This study describes racial disparities in patient‐reported symptom burden during routine oncology care, primarily observed in Black patients. Clinic‐based electronic symptom monitoring may be useful to detect high symptom burden, particularly in patients who self‐identify their race as Black or other. Future research is needed to reduce symptom burden in racially diverse cancer populations.
Optimization of the light‐emitting diode daylight simulator based on the CIE metamerism index method
Authors: Zhao Yifei , Zhong Ping , He Guoxing
Published: June 2021

By using spectral loss simulation, it was found that six spectral bands are needed to produce a daylight simulator with good performance. The optimization model for both Commission Internationale de l'Eclairage metamerism index and luminous efficacy (LE) of light‐emitting diode (LED) daylight simulator (LDS) was developed. The optimal LDSs with AA grade for D50, D55, D65, and D75 illuminants should consist of the violet LEDs with violet phosphor excited by an ultraviolet chip, and the white LEDs with green, yellow, and red phosphors excited by a blue chip. Their limit luminous efficacies under the ideal case could reach 179 to 204 lm/W. And finally, a scheme for a spectrally tunable LDS with AA grade was presented.
Tuning the UV/Vis Absorption Spectra of Electrochromic Small Molecular Radicals Through Bridge Modulation
Authors: Yu Lirong , Shi Ming , Wang Zikuan , Xing Xing , Umair Ali Muhammad , He Yaowu , Meng Hong
Published: June 2021

Studies on the optical properties of donor‐bridge‐acceptor (DBA) materials in their radical anion state are rare but important. Such investigations can help to extend the application of DBA materials to opto‐electrochemical devices and no longer limit them to optical physics research. In this work, a series of new DBA materials, TACzs, for overcoming this limitation are reported. All TACzs show strong intramolecular charge transfer (ICT) in their photoexcited states, leading to noticeable solvatochromism. Besides, the electronic structures of their radical anions show great variability, displaying different absorption spectra and diverse colors. Moreover, the potential application of TACzs as electrochromic and electro‐fluorochromic materials are discussed. This work demonstrates that manipulating the π bridge between the donor and acceptor in the DBA system is an effective pathway not only to tailor the ICT properties of materials in their neutral state, but also to tune the absorption characteristics of their radical anion state, which makes them very promising for applications in electroluminescent and electrochemical devices.
The Role of Pharmacogenetics in Smoking
Authors: El‐Boraie Ahmed , Tyndale Rachel F.
Published: June 2021

Smoking continues to be the leading preventable contributor to death worldwide. Twin studies have suggested a significant genetic contribution underlying most smoking behaviors (40–70% heritability estimates). Candidate gene studies of smoking phenotypes have identified several pharmacogenes implicated in nicotine’s pharmacokinetics (CYP2A6, CYP2B6, CYP2A13, FMOs, UGTs, and OCT2), and nicotine’s pharmacodynamic response in the central nervous system (nicotinic acetylcholine receptors, as well as through the dopaminergic and serotonergic systems). Subsequent genome‐wide association studies (GWAS) have confirmed the role of certain pharmacogenes through hypothesis‐free approaches. Furthermore, pharmacogenes that alter the efficacy of smoking cessation pharmacotherapies, including nicotine replacement therapies, bupropion, and varenicline, may also impact quitting success. In this brief review we highlight the role of pharmacogenes in smoking behaviors, such as smoking status, consumption, nicotine dependence, spontaneous quitting, and altered abstinence to pharmacotherapies; We provide examples from initial candidate gene associations and subsequent GWAS. The genes CYP2A6 and the CHRNA5‐A3‐B4 confer the most replicated sources of genetic variation in smoking behaviors, likely due to their importance in nicotine’s pharmacology. We will also provide examples of genetic scoring approaches, and the role of rare variants in explaining a portion of the missing heritability in smoking behaviors.
Roles and Impacts of Ancillary Materials for Multi‐Component Blend Organic Photovoltaics towards High Efficiency and Stability
Authors: Kim Minjun , Choi Yelim , Hwan Lee Dae , Min Jihyun , Pu Yong‐Jin , Park Taiho
Published: June 2021

Organic photovoltaics (OPVs) are a promising next‐generation photovoltaic technology with great potential for wearable and transparent device applications. Over the past decades, remarkable advances in device efficiency close to 20 % have been made for bulk heterojunction (BHJ)‐based OPV devices with long‐term stability, and room for further improvements still exists. In recent years, ancillary components have been demonstrated as effective in improving the photovoltaic performance of OPVs by controlling the optoelectronic and morphological properties of BHJ blends. Herein, an updated understanding of polymer‐based blend OPVs is provided, and the role and impact of ancillary components in various blend systems are categorized and discussed. Lastly, a strategic perspective on the ancillary components of blend‐based OPVs for commercialization is provided.
Living in the concrete jungle: carnivore spatial ecology in urban parks
Authors: Gámez Siria , Harris Nyeema C.
Published: June 2021

People and wildlife are living in an increasingly urban world, replete with unprecedented human densities, sprawling built environments, and altered landscapes. Such anthropogenic pressures can affect multiple processes within an ecological community, from spatial patterns to interspecific interactions. We tested two competing hypotheses, human shields vs. human competitors, to characterize how humans affect the carnivore community using multispecies occupancy models. From 2017 to 2020, we conducted the first camera survey of city parks in Detroit, Michigan, and collected spatial occurrence data of the local native carnivore community. Our 12,106–trap night survey captured detection data for coyotes (Canis latrans), red foxes (Vulpes vulpes), raccoons (Procyon lotor), and striped skunks (Mephitis mephitis). Overall occupancy varied across species (Ψcoyote = 0.40, Ψraccoon = 0.54, Ψred fox = 0.19, Ψstriped skunk = 0.09). Contrary to expectations, humans did not significantly affect individual occupancy for these urban carnivores. However, co‐occurrence between coyote and skunk increased with human activity. The observed positive spatial association between an apex and subordinate pair supports the human shield hypothesis. Our findings demonstrate how urban carnivores can exploit spatial refugia and coexist with humans in the cityscape.
Climate and species stress resistance modulate the higher survival of large seedlings in forest restorations worldwide
Authors: Andivia Enrique , Villar‐Salvador Pedro , Oliet Juan A. , Puértolas Jaime , Dumroese R. Kasten , Ivetić Vladan , Molina‐Venegas Rafael , Arellano Eduardo C. , Li Guolei , Ovalle Juan F.
Published: June 2021

Seedling planting plays a key role in active forest restoration and regeneration of managed stands. Plant attributes at outplanting can determine tree seedling survival and consequently early success of forest plantations. Although many studies show that large seedlings of the same age within a species have higher survival than small ones, others report the opposite. This may be due to differences in environmental conditions at the planting site and in the inherent functional characteristics of species. Here, we conducted a global‐scale meta‐analysis to evaluate the effect of seedling size on early outplanting survival. Our meta‐analysis covered 86 tree species and 142 planting locations distributed worldwide. We also assessed whether planting site aridity and key plant functional traits related to abiotic and biotic stress resistance and growth capacity, namely specific leaf area and wood density, modulate this effect. Planting large seedlings within a species consistently increases survival in forest plantations worldwide. Species’ functional traits modulate the magnitude of the positive seedling size–outplanting survival relationship, showing contrasting effects due to aridity and between angiosperms and gymnosperms. For angiosperms planted in arid/semiarid sites and gymnosperms in subhumid/humid sites the magnitude of the positive effect of seedling size on survival was maximized in species with low specific leaf area and high wood density, characteristics linked to high stress resistance and slow growth. By contrast, high specific leaf area and low wood density maximized the positive effect of seedling size on survival for angiosperms planted in subhumid/humid sites. Results have key implications for implementing forest plantations globally, especially for adjusting nursery cultivation to species’ functional characteristics and planting site aridity. Nursery cultivation should promote large seedlings, especially for stress sensitive angiosperms planted in humid sites and for stress‐resistant species planted in dry sites.
Seasonal temperature–moisture interactions limit seedling establishment at upper treeline in the Southern Rockies
Authors: Bailey Sydney N. , Elliott Grant P. , Schliep Erin M.
Published: June 2021

Over recent decades, sharply rising temperatures without an accompanying increase in precipitation have created widespread heat‐induced drought stress, or hotter drought. Tree‐ring reconstructions have discovered significant declines in seedling establishment from hotter drought across montane and subalpine forest belts during this time, yet comparable studies at upper treeline are non‐existent. In this study, we reconstruct annual patterns of seedling establishment at upper treeline in the Southern Rocky Mountains to test the hypotheses that establishment is governed by temperature–moisture interactions and that slope aspect mediates the influence of hotter drought. To test these hypotheses, we destructively sampled seedlings along a network of six study sites to reconstruct annual patterns of establishment on opposite north‐facing and south‐facing slopes. Results from this research can be summarized into two main points with respect to the influence of climate on seedling establishment at upper treeline over approximately the last three decades (1991–2019). First, temperature–moisture interactions throughout the year play a crucial role in facilitating successful seedling establishment. Second, and perhaps most striking, is the complete lack of establishment at all sites over the past decade. This could signify that a threshold has been surpassed and conditions are now beyond the climatic optimum for successful seedling establishment above treeline moving forward. These results expand upon similar findings from forests at lower elevations, introducing the likelihood that seedling establishment along the entire mountain forest belt of the Southern Rocky Mountains is being impacted by hotter drought. This means that any declines in the rate of seedling establishment across montane and subalpine forests will not be offset by increased recruitment at treeline.
A private channel of nitrogen alleviates interspecific competition for an annual legume
Authors: Elias J. D. , Agrawal A. A.
Published: June 2021

The way resource availability predictably alters interspecific interactions and may favor one resource‐acquisition strategy over another is critical for understanding context dependency. The ubiquity of nitrogen (N) limitation across terrestrial environments is a driver of plant competition and the association of some plants with N‐fixing bacteria (rhizobia) may alleviate competition with nonfixing plants. Conversely, when available soil N is elevated, competitive advantages imparted by rhizobia are hypothesized to decline because nonfixing species are able to acquire those nutrients readily. We manipulated competition, soil N, and soil microbial inoculation, employing the ground bean Amphicarpaea bracteata, a native annual N‐fixing legume, and jewelweed Impatiens capensis, a native co‐occurring nonfixing annual. We found that legume performance was negatively impacted by interspecific competition, but less so under lower soil N in both the greenhouse and field. The legume invested a greater proportion of resources in rhizobia when competing, but only under low N. Also consistent with predictions, a competition‐by‐microbial‐inoculation interaction demonstrated that negative effects of competition were alleviated by rhizobia. Finally, we detected an interaction between inoculation and fertilization, whereby N addition resulted in increased performance for uninoculated legumes, but a small decline in performance for inoculated plants, the latter likely representing a cost of mutualism. Thus, several lines of evidence point to the legume–rhizobia mutualism being more beneficial under competition and limited soil N. Competing I. capensis, in contrast, benefited from N addition regardless of the addition of soil microbes. In a survey of natural populations, legume and rhizobia growth were positively correlated at population edges (where interspecific competition is expected to be higher, the mutualism is stronger), whereas at population centers we found no association. Isotopic evidence confirmed a higher degree of rhizobial N‐fixation at population edges compared to centers. Taken together, our results demonstrate an important role for the largely private channel of nitrogen in legume competitive performance, but with the benefits imparted by rhizobia being predictably weaker at higher soil fertility. We speculate that alleviation of competitive impacts through resource partitioning is an important and yet largely overlooked aspect of the evolutionary ecology of legume–rhizobia interactions.