bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of additives in fabrication of soy‐based rigid polyurethane foam for structural and thermal insulation applications
Authors: Bose Mousumi , Dhaliwal Gurjot , Chandrashekhara K. , Nam Paul
Published: July 2021

Environmental concerns continue to pose the challenge to replace petroleum‐based products with renewable ones completely or at least partially while maintaining comparable properties. Herein, rigid polyurethane (PU) foams were prepared using soy‐based polyol for structural and thermal insulation applications. Cell size, density, thermal resistivity, and compression force deflection (CFD) values were evaluated and compared with that of petroleum‐based PU foam Baydur 683. The roles of different additives, that is, catalyst, blowing agent, surfactants, and different functionalities of polyol on the properties of fabricated foam were also investigated. For this study, dibutyltin dilaurate was employed as catalyst and water as environment friendly blowing agent. Their competitive effect on density and cell size of the PU foams were evaluated. Five different silicone‐based surfactants were employed to study the effect of surface tension on cell size of foam. It was also found that 5 g of surfactant per 100 g of polyol produced a foam with minimum surface tension and highest thermal resistivity (R value: 26.11 m2·K/W). However, CFD values were compromised for higher surfactant loading. Additionally, blending of 5 g of higher functionality soy‐based polyol improved the CFD values to 328.19 kPa, which was comparable to that of petroleum‐based foam Baydur 683.
Biopolymer‐based microparticles for encapsulation of all‐trans‐retinoic acid
Authors: A. Silva Letícia , Dambros Roberta , R. Leonardi Gislaine , Perrechil Fabiana
Published: July 2021

This work aims to investigate the potential of complex coacervation technique to encapsulate and protect all‐trans retinoic acid (RA). Gelatin and κ‐carrageenan were used as wall material and pequi oil was employed as a hydrophobic phase. Three formulations with different protein: polysaccharide ratio and pH were defined to produce the microparticles based on the zeta potential and turbidity analysis: (F1) ratio 3:1 and pH 3.5, (F2) ratio 8:1 and pH 3.5, and (F3) ratio 8:1 and pH 5.0. Microparticles were evaluated regarding their morphology, yield, encapsulation efficiency (EE), and stability. The properties of microparticles were mainly affected by the protein: polysaccharide ratio and the turbidity of the mixtures, which is directly related to the protein‐polysaccharide interaction. Formulation 1 showed the optimal values of yield (75.6%), EE (100.2%), and stability (85% of the encapsulated RA remained in the particle). The results demonstrated the high potential of this innovative technique to encapsulate RA for a future application in topical formulations.
Integrated Suzuki Cross‐Coupling/Reduction Cascade Reaction of meta‐/para‐Chloroacetophenones and Arylboronic Acids under Batch and Continuous Flow Conditions
Authors: Li Yilong , Wang Chengyi , Chen Qipeng , Li Hongyu , Su Yu , Cheng Tanyu , Liu Guohua , Tan Chunxia
Published: July 2021

Overcoming the incompatibility of a pair of conflicting catalysts via a flow methodology has great significance in the practical applications for multistep organic transformations. In this study, a multiple continuous‐flow system is developed, which can boost the reactivity and selectivity in a sequential enantioselective cascade reaction. During this process, a periodic mesoporous organosilica‐supported Pd/carbene species as a Suzuki cross‐coupling catalyst is packed in the first column reactor, whereas another periodic mesoporous organosilica‐supported Ru/diamine species as an asymmetric transfer hydrogenation catalyst is packed in the second column reactor. As we envisioned, the initially Pd‐catalyzed cross‐coupling reaction of meta‐/para‐chloroacetophenones and aryl boronic acids followed by the subsequentially Ru‐catalyzed reduction provides chiral biarylols with enhanced yields and enantioselectivities. Furthermore, the advantages of the easy handling and the simple procedure make this system an attractive application in a scale‐up preparation of optically pure organic molecules under environmentally‐friendly conditions.
18O/16O‐Encoding Strategy for Microscale Stereochemical Determination of Peptidic Natural Products
Authors: Takeuchi Aoi , Itoh Hiroaki , Inoue Masayuki
Published: July 2021

The demand for more efficient methods of establishing the undetermined stereochemistries of peptidic natural products continues unabated. A new method for microscale stereochemical determination was devised by integrating solid‐phase synthesis, split‐and‐mix randomization, 18O/16O‐encoding of d/l‐configurations, tandem mass spectrometry, and biological evaluation. Here we applied gramicidin A as the molecule for a blind test. Gramicidin A and its 31 diastereomers were randomly prepared in microgram scale with 18O/16O‐stereochemical encoding and subjected to MS/MS‐structural determination and cytotoxicity assay. Only the parent gramicidin A was selected from among the 32 stereoisomers, validating the high reliability of the present strategy.
Design of Vacuum Post‐Drying Procedures for Electrodes of Lithium‐Ion Batteries
Authors: Huttner Fabienne , Marth Axel , Eser Jochen C. , Heckmann Thilo , Mohacsi Jonas , Mayer Julian K. , Scharfer Philip , Schabel Wilhelm , Kwade Arno
Published: July 2021

In order to reduce the residual moisture in lithium‐ion batteries, electrodes and separators need to be post‐dried prior to cell assembly. On an industrial scale, this is often conducted batch‐wise in vacuum ovens for larger electrode and separator coils. Especially for electrodes, the corresponding post‐drying parameters have to be carefully chosen to sufficiently reduce the moisture without damaging the sensitive microstructure. This requires a fundamental understanding of structural limitations as well as heat transfer and water mass transport in coils. The aim of this study is to establish a general understanding of the vacuum post‐drying process of coils. Moreover, the targeted design of efficient, well‐adjusted and application‐oriented vacuum post‐drying procedures for electrode coils on the basis of modelling is employed, while keeping the post‐drying intensity as low as possible, in order to maintain the sensitive microstructure and to save time and costs. In this way, a comparatively short and moderate 2‐phase vacuum post‐drying procedure is successfully designed and practically applied. The results show that the designed procedure is able to significantly reduce the residual moisture of anode and cathode coils, even with greater electrode lengths and coating widths, without deteriorating the sensitive microstructure of the electrodes.
Design for the environment: An ontology‐based knowledge management model for green product development
Authors: Benabdellah Abla Chaouni , Zekhnini Kamar , Cherrafi Anass , Garza‐Reyes Jose Arturo , Kumar Anil
Published: July 2021

Through appropriate operations and policies, such as green processes and product development process (PDP), companies can respond to environmental sustainability. To remain competitive, one such approach, Design for X (DFX), involves considering different environment and sustainable strategies through different factors Xs. With regard to the availability of different DFX techniques that consider environmental issues, the decision as to which approach needs to be adopted remains absent. This paper aims at presenting an overview from 1980 to 2020 of the developed research, applications, and DFX techniques for assessing green issues. Selected DFX techniques are linked with strategies used in organizations. Following a literature analysis, a collaborative knowledge‐based framework that addresses the design concepts needed to assess environmental, safety, and health concerns in the development of green products is proposed. Furthermore, as a pillar for considering the Semantic Web and an evolving approach linked with natural language processing (NLP) and artificial intelligence (AI), an ontology‐based knowledge management model for green assessment is developed for the representation, acquisition, organization, and capitalization of knowledge in a computer interpretable manner. The findings are useful for both managers and practitioners as they provide a coherent domain ontology that can help them manage knowledge, improve teamwork, and make decisions in a collaborative green PDP. Besides, an understanding of the essential design considerations that are required to implement environmental, safety, and health issues, as well as competencies used in the PDP is presented. Key barriers, managerial and strategic implications, and mitigation actions are also identified in this paper.
Moxibustion for treating cancer‐related fatigue: A multicenter, assessor‐blinded, randomized controlled clinical trial
Authors: Han Kyungsun , Kim Mikyung , Kim Eun‐Jung , Park Yeon‐Cheol , Kwon Ojin , Kim Ae‐Ran , Park Hyo‐Ju , Park Yang‐Chun , Cho Jung Hyo , Kim Joo‐Hee , Lee Jun‐Hwan
Published: July 2021

Cancer‐related fatigue (CRF) is one of the most common chronic symptoms experienced by cancer patients. As moxibustion is a popular traditional therapy for managing fatigue, it can be an alternative strategy to treat CRF as well. Therefore, we rigorously designed a full‐scale, multicenter, assessor‐blinded, randomized controlled trial to evaluate the efficacy and safety of moxibustion treatment for CRF. Ninety‐six subjects suffering from CRF were recruited and randomly assigned to moxibustion group, sham moxibustion group, or usual care group. Both the moxibustion group and the sham group received moxibustion treatment for 8 weeks and the usual care group did not. Brief fatigue inventory (BFI) score and Functional Assessment of Cancer Therapy‐Fatigue score were used to assess CRF at baseline and weeks 5, 9, and 13. Questionnaires for the assessment of cognitive impairment, quality of life, and Cold–Heat and Deficiency–Excess patterns were also evaluated. BFI scores significantly decreased in moxibustion group compared to the usual care group (mean difference of −1.92, p < 0.001 at week 9 and mean difference of −2.36, p < 0.001 at week 13). Although the sham group also showed significant improvement during the treatment period, only the moxibustion group showed improvement after 4 weeks of follow‐up period (mean difference of −1.06, p < 0.001). There were no serious adverse events. Our findings confirmed the efficacy and safety of moxibustion for CRF compared to usual care. We also found that moxibustion has a prolonged treatment effect during 4 weeks of follow‐up period.
The impact of socioeconomic status on survival in stage III colon cancer patients: A retrospective cohort study using the SEER census‐tract dataset
Authors: Dhahri Amina , Kaplan Jori , Naqvi Syeda M. H. , Brownstein Naomi C. , Ntiri Shana O. , Imanirad Iman , Felder Seth I. , Dineen Sean P. , Sanchez Julian , Dessureault Sophie , Carballido Estrella , Powers Benjamin D.
Published: July 2021

Background

The impact of socioeconomic status (SES) has been described for screening and accessing treatment for colon cancer. However, little is known about the “downstream” effect in patients who receive guideline‐concordant treatment. This study assessed the impact of SES on cancer‐specific survival (CSS) and overall survival (OS) for stage III colon cancer patients.

Methods

The SEER Census Tract‐Level SES Dataset from 2004 to 2015 was used to identify stage III colon adenocarcinoma patients who received curative‐intent surgery and adjuvant chemotherapy. The predictor variable was census tract SES. SES was analyzed as quintiles. The outcome variables were OR and CSS. Statistical analysis included chi square tests for association, Kaplan–Meier, Cox, Fine and Gray regression for survival analysis.

Results

In total, 27,222 patients met inclusion criteria. Lower SES was associated with younger age, Black or Hispanic race/ethnicity, Medicaid/uninsured, higher T stage, and lower grade tumors. CSS at the 25th percentile was 54 months for the lowest SES quintile and 80 for the highest. Median OS was 113 months for the lowest SES quintile and not reached for highest. The 5‐year CSS rate was 72.4% for the lowest SES quintile compared to 78.9% in the highest (p < 0.001). The 5‐year OS rate was 66.5% for the lowest SES quintile and 74.6% in the highest (p < 0.001).

Conclusion

This is the first study to evaluate CSS and OS in an incidence‐based cohort of stage III colon cancer patients using a granular, standardized measure of SES. Despite receipt of guideline‐based treatment, SES was associated with disparities in CSS and OS.
A prognostic nomogram based on competing endogenous RNA network for clear‐cell renal cell carcinoma
Authors: Peng Yun , Wu Shangrong , Xu Zihan , Hou Dingkun , Li Nan , Zhang Zheyu , Wang Lili , Wang Haitao
Published: July 2021

Background

Clear‐cell renal cell carcinoma (ccRCC) is stubborn to traditional chemotherapy and radiation treatment, which makes its clinical management a major challenge. Recently, we have made efforts in understanding the etiology of ccRCC. Increasing evidence revealed that the competing endogenous RNA (ceRNA) was involved in the development of varied tumors. However, a comprehensive analysis of the prognostic model based on lncRNA‐miRNA‐mRNA ceRNA regulatory network of ccRCC with large‐scale sample size and RNA‐sequencing expression data is still limited.

Methods

RNA‐sequencing expression data were taken out from GTEx database and TCGA database, a total of 354 samples with ccRCC and 157 normal controlled samples were included in our study. The ccRCC‐specific genes were obtained by WGCNA and differential expression analysis. Following, the communication of mRNAs and lncRNAs with targeted miRNAs were predicted by MiRcode, starBase, miRTarBase, and TargetScan. A gene signature of eight genes was further constructed by univariate Cox regression, Lasso methods, and multivariate Cox regression analysis.

Results

A total of 2191 mRNAs and 1377 lncRNAs was identified, and a dysregulated ceRNA network for ccRCC was established using 7 mRNAs, 363 lncRNAs, and 3 miRNAs. Further, a gene signature including eight genes based on this ceRNA was determined followed by the development of a nomogram predicting 1‐, 3‐, and 5‐year survival probability for ccRCC.

Conclusion

It could contribute to a better understanding of ccRCC tumorigenesis mechanism and guide clinicians to make a more accurate treatment decision.
The transcription factor TEAD4 enhances lung adenocarcinoma progression through enhancing PKM2 mediated glycolysis
Authors: Hu Yan , Mu Hanshuo , Deng Zhiping
Published: July 2021

Lung adenocarcinoma (LUAD) is a deadly disease with a hallmark of aberrant metabolism. TEA domain 4 (TEAD4) is involved in the progression of several forms of cancer including LUAD. However, the role of TEAD4 in LUAD glucose metabolism is rarely reported as well as its potential mechanisms. Pyruvate kinase isozymes M2 (PKM2), the key regulatory enzymes in glycolysis, was predicted to be a target for TEAD4 by bioinformatics analysis. Thus, we aimed to explore whether TEAD4/PKM2 axis was related to LUAD glucose metabolism and malignant phenotype. The expression level of TEAD4 and PKM2 was measured by quantitative real‐time PCR and Western blot. Luciferase reporter assay were employed to verify the effect of TEAD4 on PKM2 promoter as well as TEAD4/PKM2 axis on reporter activity of hypoxia inducible factor‐1α (HIF‐1α). Glycolysis was investigated according to glucose consumption, lactate production and the extracellular acidification rate. The present study indicated that TEAD4 and PKM2 were upregulated in LUAD and closely related to prognosis. Mechanistic investigations identified that TEAD4 played a key role as a transcription factor and promoted PKM2 transcription and expression, which further altered the reporter activity of HIF‐1α and upregulated HIF‐1α‐targeted glycolytic genes glucose transporter‐1 and hexokinase II. Functional assays revealed that TEAD4 and PKM2 affected glycolytic and 2‐DG blocked the positive function of TEAD4 and PKM2 on glycolytic. Besides, TEAD4/PKM2 axis affects LUAD cell viability, apoptosis, migration, and invasion. Together, these data provided evidence that both TEAD4 and PKM2 were poor prognosticator. Targeting TEAD4/PKM2 axis might be an effective therapeutic strategy for LUAD.
(NH4)2V7O16 Microbricks as a Novel Anode for Aqueous Lithium‐Ion Battery with Good Cyclability
Authors: Ma Yining , Wu Mingchen , Jin Xiaodong , Shu Rui , Hu Chenchen , Xu Tongxiang , Li Jing , Meng Xinyu , Cao Xun
Published: July 2021

Searching for novel anode materials to address the issues of poor cycle stability in the aqueous lithium‐ion battery system is highly desirable. In this work, ammonium vanadium bronze (NH4)2V7O16 with brick‐like morphology has been investigated as an anode material for aqueous lithium‐ion batteries and Li+/Na+ hybrid ion batteries. The two novel full cell systems (NH4)2V7O16||Li2SO4||LiMn2O4 and (NH4)2V7O16||Na2SO4||LiMn2O4 both demonstrate good rate capability and excellent cycling performance. A capacity retention of 78.61 % after 500 cycles at 300 mA g−1 was demonstrated in the (NH4)2V7O16||Li2SO4||LiMn2O4 system, whereas no capacity attenuation is observed in the (NH4)2V7O16||Na2SO4||LiMn2O4 system. The reaction mechanisms of the (NH4)2V7O16 electrode and impedance variation of the two full cells were also researched. The excellent cycling stability suggests that layered (NH4)2V7O16 can be a promising anode material for aqueous rechargeable lithium‐ion batteries.
[Ni(NHC)2] as a Scaffold for Structurally Characterized trans [H−Ni−PR2] and trans [R2P−Ni−PR2] Complexes
Authors: Sabater Sara , Schmidt David , Schmidt Heidi (née Schneider) , Kuntze‐Fechner Maximilian W. , Zell Thomas , Isaac Connie J. , Rajabi Nasir A. , Grieve Harry , Blackaby William J. M. , Lowe John P. , Macgregor Stuart A. , Mahon Mary F. , Radius Udo , Whittlesey Michael K.
Published: July 2021

The addition of PPh2H, PPhMeH, PPhH2, P(para‐Tol)H2, PMesH2 and PH3 to the two‐coordinate Ni0 N‐heterocyclic carbene species [Ni(NHC)2] (NHC=IiPr2, IMe4, IEt2Me2) affords a series of mononuclear, terminal phosphido nickel complexes. Structural characterisation of nine of these compounds shows that they have unusual trans [H−Ni−PR2] or novel trans [R2P−Ni−PR2] geometries. The bis‐phosphido complexes are more accessible when smaller NHCs (IMe4>IEt2Me2>IiPr2) and phosphines are employed. P−P activation of the diphosphines R2P−PR2 (R2=Ph2, PhMe) provides an alternative route to some of the [Ni(NHC)2(PR2)2] complexes. DFT calculations capture these trends with P−H bond activation proceeding from unconventional phosphine adducts in which the H substituent bridges the Ni−P bond. P−P bond activation from [Ni(NHC)2(Ph2P−PPh2)] adducts proceeds with computed barriers below 10 kcal mol−1. The ability of the [Ni(NHC)2] moiety to afford isolable terminal phosphido products reflects the stability of the Ni−NHC bond that prevents ligand dissociation and onward reaction.
Chemodynamic Therapy Combined with Multifunctional Nanomaterials and Their Applications in Tumor Treatment
Authors: Yu Zhenghao , Hu Yue , Sun Yuan , Sun Tiedong
Published: July 2021

During the past few decades, radiotherapy and chemotherapy have been the standard approaches for tumor treatments. However, the potential toxic effect and side effects of both radiotherapy and chemotherapy on the human body still cannot be neglected. Given this, the Fenton reaction has become one of the most effective treatment strategies to combat tumor cells. This review aims to summarize the recent advances comprehensively and systematically in chemodynamic therapy (CDT) via the Fenton reaction. In addition, a host of the advanced nano‐multifunctional materials and engineering bacteria used in the Fenton reaction were also summarized. This paper would be helpful to provide guidance and lay firm foundations for future tumor treatment.
Cata‐Annulated Azaacene Bisimides
Authors: Elter Maximilian , Ahrens Lukas , Luo Stella M. , Rominger Frank , Freudenberg Jan , Cao Dennis D. , Bunz Uwe H. F.
Published: July 2021

Ultra‐electron‐deficient azaacenes were synthesized via Buchwald‐Hartwig coupling of ortho‐diaminoarenes with chlorinated mellophanic diimide followed by oxidation of the intermediate N,N’‐dihydro compounds with MnO2 or PbO2. The resulting cata‐annulated bisimide azaacenes have ultrahigh electron affinities with first reduction potentials as low as −0.35 V recorded for a tetraazapentacene. Attempts to prepare a tetrakis(dicarboximide)tetraazaheptacene resulted in the formation of a symmetric butterfly dimer.
Ionic Liquids [M3+][A−]3 with Three‐Valent Cations and Their Possible Use to Easily Separate Rare Earth Metals
Authors: Rothe Manuel , Tress Martin , Allacher Carina , Nuernberger Patrick , Kunz Werner
Published: July 2021

We introduce a simple way to liquify rare earth metals (REM) by incorporating the corresponding cations, in particular Eu3+, La3+, and Y3+, into polyvalent ionic liquids (ILs). In contrast to conventional methods, this is achieved not by transforming them into anionic complexes, but by keeping them as bare cations and combining them with convenient, cheap and commercially available anions (A) in the form [REM3+][A−]3. To do so, we follow the COncept of Melting Point Lowering due to EThoxylation (COMPLET) with alkyl polyethylene oxide carboxylates as anions. We provide basic properties, such as glass transition temperatures, viscosities, electrical conductivities, as well as water‐octanol partition constants P and show that these ILs have remarkably different properties, despite the similarity of their cations. In addition, we show that the ionic liquids possess interesting luminescent properties as non‐conventional fluorophores.
What Is the Catalytic Mechanism of Enzymatic Histone N‐Methyl Arginine Demethylation and Can It Be Influenced by an External Electric Field?
Authors: Ramanan Rajeev , Waheed Sodiq O. , Schofield Christopher J. , Christov Christo Z.
Published: July 2021

Invited for the cover of this issue are Christo Z. Christov and co‐workers at Michigan Technological University and University of Oxford. The image depicts the effects of applying an external electric field on the demethylation of dimethylated arginine substrate by a non‐heme Fe center Histone N‐methyl arginine demethylase. Read the full text of the article at 10.1002/chem.202101174.
Uncommon N‐Methoxyindolediketopiperazines from Acrostalagmus luteoalbus, a Marine Algal Isolate of Endophytic Fungus
Authors: Cao Jin , Li Xiao‐Ming , Li Xin , Li Hong‐Lei , Konuklugil Belma , Wang Bin‐Gui
Published: July 2021

Main observation and conclusion

Four new N‐methoxyindolediketopiperazines (acrozines D—G, 1—4) and six known congeners (5—10) were purified from the organic extract of Acrostalagmus luteoalbus TK‐43, which was a marine algal‐derived fungus obtained from Codium fragile. Their structures were determined by interpretation of NMR and mass spectroscopic data. The structures of compounds 1, 2, and 4 including their absolute configurations were confirmed by single‐crystal X‐ray diffraction, while the absolute configuration of compound 3 was elucidated by comparative analysis of ECD and TDDFT‐ECD calculations. Compounds 1—4, with a unique methoxy substitution at N‐2, were rarely discovered among indolediketopiperazine alkaloids. All these compounds were evaluated for antimicrobial activities against human‐ and aquatic‐pathogenic bacteria and plant‐related pathogenic fungi, with compounds 5 and 7 exhibiting potent activity against Edwardsiella icataluri (MIC = 3 and 5 μmol/L, respectively), while compound 9 displayed a broad spectrum of antibacterial activities. The four new compounds were further tested for anti‐acetylcholinesterase (AChE) properties, and compound 3 exhibited inhibitory activity with IC50 value of 8.4 μmol/L.
Revisiting the fluorescent mosaic technique
Authors: Travis M.F.A. Richard
Published: July 2021

A visual art technique first described in an early issue of CR&A is discussed here in the way it has been modified to expand its practicality. As a first‐of‐its‐kind application of additive color mixture in the two‐dimensional visual arts, the fluorescent mosaic technique is considered in terms of its historical context, and its conceptual and technical development are presented as it grew out of an awareness of a theoretical dissonance between the worlds of art and science. Three visual designs created in the additive fluorescent mosaic technique as proof‐of‐concept demonstrations are presented and discussed as they evolved from early methods requiring special lighting, which severely restricted the technique's applicability, to a more broadly functional method requiring only white light that is strong in blue content, such as average daylight. Because digital photography and electronic displays capture the appearance of fluorescent mosaic images quite well, their use as an educational instrument for teaching color mixture theory on a wide‐scale basis is promising. An outline of basic procedures for creating fluorescent mosaic artwork is provided. As a fine art medium, it is an area of visual expression that is virtually unexplored. Lastly, other approaches to creating visual art using luminous mosaic imagery are suggested.
Species–environment relationships of fish and map‐based variables in small boreal streams: Linkages with climate change and bioassessment
Authors: Sutela Tapio , Vehanen Teppo , Jounela Pekka , Aroviita Jukka
Published: July 2021

Species–environment relationships were studied between the occurrence of 13 fish and lamprey species and 9 mainly map‐based environmental variables of Finnish boreal small streams. A self‐organizing map (SOM) analysis showed strong relationships between the fish species and environmental variables in a single model (explained variance 55.9%). Besides basic environmental variables such as altitude, catchment size, and mean temperature, land cover variables were also explored. A logistic regression analysis indicated that the occurrence probability of brown trout, Salmo trutta L., decreased with an increasing percentage of peatland ditch drainage in the upper catchment. Ninespine stickleback, Pungitius pungitius (L.), and three‐spined stickleback, Gasterosteus aculeatus L., seemed to benefit from urban areas in the upper catchment. Discovered relationships between fish species occurrence and land‐use attributes are encouraging for the development of fish‐based bioassessment for small streams. The presented ordination of the fish species in the mean temperature gradient will help in predicting fish community responses to climate change.
The Role of Grain Boundaries in Charge Carrier Dynamics in Polycrystalline Metal Halide Perovskites
Authors: Gegevičius Rokas , Franckevičius Marius , Gulbinas Vidmantas
Published: July 2021

Boundaries of perovskite grains forming polycrystalline films are the most sensitive place for the formation of the defect states and accumulation of impurities. The intra‐bandgap states located at the boundaries forming traps for charge carriers are commonly discussed as causing nonradiative carrier recombination and reducing carrier mobility. Grain boundaries (GB) may also disturb carrier motion by creating scattering centres and barriers, however, their role was less frequently considered. On the other hand, grain boundaries may also facilitate the splitting of exciton states and the generation of free charge carriers. Consequently, the grain boundaries are responsible or affect a wide range of perovskite properties and processes strongly influencing the performance of perovskite‐based optoelectronic devices. Nevertheless, abundant literature data related to the properties of grain boundaries and their influence are highly controversial. In this minireview, we discuss the most importnat literature data related to the structure and properties of grain boundaries and their role in device performance.
Sonogashira Cross‐Coupling Reaction of Bromocyanofluoro Pyridine Compounds: Access to 5‐ and 6‐Alkynylfluoropyridinamidoximes Scaffolds
Authors: Razafindrainibe Franck , Voros Camille , Jagadeesh Yerri , Reddy Nimmakayala Mallikarjuna , Tissier Allan , Mardy Keven , Reihanian‐Hadany Norbert , Brown Richard C. D. , Baati Rachid
Published: July 2021

We disclose a general two‐step procedure to access hitherto unknown and under explored 5‐ and 6‐alkynyl‐3‐fluoro‐2‐pyridinamidoximes from 5‐ and 6‐bromo‐3‐fluoro‐2‐cyanopyridines and a wide range of easily available and bench‐stable terminal alkynes, using Sonogashira cross‐coupling, as the first step. The generation of the polar amidoxime group is realized at a late stage upon treatment of the alkynylfluorocyanopyridine by hydroxylamine. This mild and operationally simple two‐step room temperature process is compatible with enantiopure chiral substrates and various functionality including free alcohols, unprotected and CBz‐protected amines, acetonides, benzyl ethers, amide, imide, di‐substituted alkynes and strained saturated heterocycles.
The 2‐Propanol Fuel Cell: A Review from the Perspective of a Hydrogen Energy Economy
Authors: Brodt Matthew , Müller Karsten , Kerres Jochen , Katsounaros Ioannis , Mayrhofer Karl , Preuster Patrick , Wasserscheid Peter , Thiele Simon
Published: July 2021

The 2‐propanol fuel cell has been shown to hold several key advantages over the more established methanol fuel cell, including a comparably high real open‐circuit voltage, reduced fuel crossover through a Nafion membrane and a benign toxicological fuel profile. In addition, while the highly selective partial oxidation of 2‐propanol to acetone in a fuel cell (rather than the more typical complete combustion of organic fuels to CO2) has been viewed as a disadvantage in the past, recent work has shown that the 2‐propanol/acetone couple is compatible with traditional hydrocarbon liquid organic hydrogen carrier (LOHC) systems though transfer hydrogenation. With this approach, a disadvantage of hydrogen LOHC logistics—the steep energy cost of dehydrogenation that must be provided during energy‐lean times—can be largely avoided. This LOHC compatibility along with the potential for high fuel‐cell performance could place the 2‐propanol fuel cell (also referred to as the direct isopropanol fuel cell or DIFC) in a position to enable a hydrogen energy economy while avoiding the drawbacks of molecular hydrogen transport and storage. In this Review, the purpose is to ascertain the state‐of‐the‐art of DIFCs—an understudied yet promising research area with unique advantages and challenges.
A highly sensitive magnetic configuration‐based triboelectric nanogenerator for multidirectional vibration energy harvesting and self‐powered environmental monitoring
Authors: Park Minseok , Cho Sumin , Yun Yeongcheol , La Moonwoo , Park Sung Jea , Choi Dongwhi
Published: July 2021

Vibration energy, which is ubiquitous but usually abandoned energy, has been considered as a promising source of energy to be harvested for future power supply to electronics. In this study, we demonstrate the triboelectric nanogenerator (TENG) with a rationally designed bi‐axial vibration responsive magnetic configuration (BVMC). Oblique placement of two magnets enables the system to be bi‐axially sensitive and the superior response of such BVMC to vibrations is explored for further utilized to harvest multidirectional vibration energy in a single device. Energy harvesting performance of the multidirectional vibration stimuli‐responsive TENG, called MS‐TENG, under various vibration conditions is investigated. In addition, the further development of the MS‐TENG with an additional magnet exhibits the full (three‐dimensional) vibration energy harvesting ability. The MS‐TENG is applied under‐the‐hood of an automobile where typically abandoned vibrations occur frequently. Turning on the engine on the ignition enables the arrayed MS‐TENG to generate a stable output just by engine trembling. Furthermore, the normal human motion‐driven vibration is used to charge the commercial capacitor to wirelessly transmit the signal including information of ambient temperature and humidity from the Bluetooth thermo‐hygrometer sensor. Consequently, the present TENG with simple but bi‐axially sensitive magnetic configuration has a great potential to effectively harvest the multidirectional and low‐frequency vibrations around us for future feasible applications.
Larger cells have relatively smaller nuclei across the Tree of Life
Authors: Malerba Martino E. , Marshall Dustin J.
Published: July 2021

Larger cells have larger nuclei, but the precise relationship between cell size and nucleus size remains unclear, and the evolutionary forces that shape this relationship are debated. We compiled data for almost 900 species – from yeast to mammals – at three scales of biological organisation: among-species, within-species, and among-lineages of a species that was artificially selected for cell size. At all scales, we showed that the ratio of nucleus size to cell size (the ‘N: C’ ratio) decreased systematically in larger cells. Size evolution appears more constrained in nuclei than cells: cell size spans across six orders of magnitude, whereas nucleus size varies by only three. The next important challenge is to determine the drivers of this apparently ubiquitous relationship in N:C ratios across such a diverse array of organisms.
Metapopulation structure modulates sexual antagonism
Authors: Rodriguez-Exposito E. , Garcia-Gonzalez F.
Published: July 2021

Despite the far-reaching evolutionary implications of sexual conflict, the effects of metapopulation structure, when populations are subdivided into several demes connected to some degree by migration, on sexual conflict dynamics are unknown. Here, we used experimental evolution in an insect model system, the seed beetle Callosobruchus maculatus, to assess the independent and interacting effects of selection histories associated with mating system (monogamy vs. polygamy) and population subdivision on sexual conflict evolution. We confirm traditional predictions from sexual conflict theory by revealing increased resistance to male harm in females from populations with a history of intense sexual selection (polygamous populations) compared to females from populations with a history of relaxed sexual selection (monogamous populations). However, selection arising from metapopulation structure reversed the classic pattern of sexually antagonistic coevolution and led to reduced resistance in females from polygamous populations. These results underscore that population spatial structure moderates sexual selection and sexual conflict, and more broadly, that the evolution of sexual conflict is contingent on ecological context. The findings also have implications for population dynamics, conservation biology, and biological control.
Structural modification and biological activities of carboxymethyl Pachymaran
Authors: Yan You‐Yu , Yuan Shuai , Ma Hao‐Hai , Zhang Xi‐Feng
Published: July 2021

Polysaccharides are good chelating agents for metal ions, which are often used to synthesize polysaccharide metal ion complexes. With carboxymethyl pachymaran (CMP) as the substrate, carboxymethyl pachymaran iron (CMPF), carboxymethyl pachymaran selenium (CMPS), and carboxymethyl pachymaran zinc (CMPZ) were synthesized by response surface methodology, and their biological characteristics were studied. The results showed that the CMP was a β‐polysaccharide, and the degree of carboxymethylation was 0.6352. The polysaccharide metal ion complexes were characterized by physicochemical methods, scanning electron microscopy, Fourier transform infrared spectroscopy, circular dichroism spectroscopy, and nuclear magnetic resonance spectroscopy. All the polysaccharides and complexes possessed antioxidant activity in vitro with scavenging activities to ABTS, superoxide anions, and ferrous ions. CMPF, CMPS, and CMPZ caused significant inhibition of A2780 cell proliferation, promoted the production of reactive oxygen species, and induced apoptosis in a human ovarian cancer cell line (A2780 cells). These results suggest that the CMP complex may be an effective candidate drug for cancer treatment in the field of functional food and pharmacology.
Stock market tail risk, tail risk premia, and return predictability
Authors: Suh Sangwon , Yoo Eungyu , Yoon Sun‐Joong
Published: July 2021

In this study, we use the S&P 500 options prices to derive various tail risk indexes. We then decompose the option‐implied tail risk indexes into the conditional tail risk of stock returns and equity tail risk premia. We examine the predictive power of the conditional tail risks and equity tail risk premia for various stock portfolio returns. The results demonstrate that the tail risk indicators possess additional predictive power for stock returns in the presence of extant risk indicators and other return predictor variables.
High Prevalence of Transjugular Intrahepatic Portosystemic Shunt Creation Without Prior Endoscopy During Acute Variceal Bleeding Hospitalization in the United States
Authors: Trivedi Premal S. , Jensen Alexandria M. , Brown Matthew A. , Morgan Rustain L. , Lindrooth Richard C. , Ryu Robert K. , Ho P. Michael , Kriss Michael S.
Published: July 2021

Current clinical guidelines by both American Association for the Study of Liver Disease and European Association for the Study of the Liver recommend endoscopy in all patients admitted with acute variceal bleeding within 12 hours of admission. Transjugular intrahepatic portosystemic shunt (TIPS) creation may be considered in patients at high risk if hemorrhage cannot be controlled endoscopically. We conducted a cross‐sectional observational study to assess how frequently TIPS is created for acute variceal bleeding in the United States without preceding endoscopy. Adult patients undergoing TIPS creation for acute variceal bleeding in the United States (n = 6,297) were identified in the last 10 available years (2007‐2016) of the National Inpatient Sample. Hierarchical logistic regression was used to examine the relationship between endoscopy nonutilization and hospital characteristics, controlling for patient demographics, income level, insurance type, and disease severity. Of 6,297 discharges following TIPS creation for acute variceal bleeding in the United States, 31% (n = 1,924) did not receive first‐line endoscopy during the same encounter. Rates of “no endoscopy” decreased with increasing population density of the hospital county (nonmicropolitan counties 43%, n = 114; mid‐size metropolitan county 35%, n = 513; and central county with >1 million population 23%, n = 527) but not by hospital teaching status (n = 1,465, 32% teaching vs. n = 430, 26% nonteaching; P = 0.10). Higher disease mortality risk (odds ratio, 0.42; 95% confidence interval, 0.22‐0.80; P = 0.02) was associated with lower odds of noncompliance. Conclusion: One third of all patients undergoing TIPS creation for acute variceal bleeding in the United States do not receive first‐line endoscopy during the same encounter. Patients admitted to urban hospitals are more likely to receive guideline‐concordant care.
Organisation of the State, model of health system and COVID‐19 health outcomes in six European countries, during the first months of the COVID‐19 epidemic in 2020
Authors: Simões Jorge , Magalhães João Paulo Moreira , Biscaia André , da Luz Pereira António , Augusto Gonçalo Figueiredo , Fronteira Inês
Published: July 2021

The time and type of the States' responses to the COVID‐19 pandemic varied with the severity of the epidemiological situation, the perceived risk, the political organisation and the model of health system of the country. We discuss the response of Germany, Spain, France, Italy, Portugal and the United Kingdom during the first months of the COVID‐19 epidemic in 2020, considering the political organisation of the country and its health system model. We analyse public health measures implemented to contain or mitigate the pandemic, as well as those related to governance, resources and reorganisation of services, financing mechanisms, response of the health system itself and health outcomes. To measure the burden of COVID‐19, we use several indicators. The adoption of measures, to contain and mitigate epidemic varied in degree and time of adoption. All countries reorganised their governance structure and the provision of care, despite the differences in political models and health systems (ranging from a more unitary and centralised political organisational model—France and Portugal; to a decentralised matrix—Germany, Spain, Italy and the United Kingdom). Rather than the differences in political models and health systems, the explanation for the success in tackling the epidemic seems to lay in other social determinants of health.
Heat and mass transport impact on MHD second‐grade fluid: A comparative analysis of fractional operators
Authors: Rehman Aziz Ur , Riaz Muhammad Bilal , Akgül Ali , Saeed Syed Tauseef , Baleanu Dumitru
Published: July 2021

The effect of the magnetic flux plays a major role in convective flow. The process of heat transfer is accompanied by a mass transfer process; for instance, condensation, evaporation, and chemical process. Due to the applications of the heat and mass transfer combined effects in different fields, the main aim of this paper is to do a comprehensive analysis of heat and mass transfer of magnetohydrodynamic (MHD) unsteady second‐grade fluid in the presence of ramped conditions. The new governing equations of MHD second‐grade fluid have been fractionalized by means of singular and nonsingular differentiable operators. To have an accurate physical significance of imposed conditions on the geometry of second‐grade fluid, the constant concentration with ramped temperature and ramped velocity is considered. The fractional solutions of temperature, concentration, and velocity have been investigated by means of integral transform and inversion algorithm. The influence of physical parameters and flow is analyzed graphically via computational software (MATHCAD‐15). The velocity profile decreases by increasing the Prandtl number. The existence of a Prandtl number may reflect the control of the thickness and enlargement of the thermal effect.
Heat and mass transport on MHD flow over semi‐infinite moving porous plate with chemical reaction effect
Authors: Kalpana M. , Vijaya R. Bhuvana
Published: July 2021

The consequences of chemical reaction, on unsteady magnetohydrodynamic heat and mass transport laminar flows of a viscous, electrically conducting with heat‐generating or absorbing fluid enclosed through a semi‐infinite absorbent plate has been premeditated. The plate is assumed to be in motion with a constant velocity within the path of fluid flow. A homogeneous magnetic field performs at right angles to the absorbent surface; it is absorbing the fluid with a suction velocity varying with a certain instant of time. The nondimensional governing equations for the present configuration are solved systematically utilizing harmonic and nonharmonic terms. Graphical consequences for the velocity, temperature, and concentration profiles together supported by the investigative solutions are displayed and discussed computationally. The resulting velocity is reducing by an augment in the strength of the magnetic field and Prandtl number, whereas it is enhancing by growing in the permeability of the porous medium. The temperature delivery is reduces by an escalating heat source parameter and occurrence of fluctuation. It is significant to note that the temperature increases notably with growing the radiation absorption parameter. The influences of the chemical reaction and Schmidt number reduced the concentration in the entire fluid medium.
A comparison of frameworks for separating the impacts of human activities and climate change on river flow in existing records and different near‐future scenarios
Authors: Andaryani Soghra , Nourani Vahid , Ball James , Jahanbakhsh Asl Saeed , Keshtkar Hamidreza , Trolle Dennis
Published: July 2021

Separating the effects of human activities/climate change on lotic ecosystems is one of the important components of environmental management as well as water resources maintenance. A Mann–Kendall analysis of hydro‐climatic parameters and vegetation cover (VC), calculated using normalized difference vegetation index (NDVI), during the period 1985–2014 suggested a significant decrease and increase of river flow and temperature at p < 0.01, as well as an insignificant decline and increment of precipitation and VC, respectively within the arid and semi‐arid region, that is, Zilbier River basin in north‐western Iran. A separation of human activities/climate change effects on the reduction of river flow was carried out using three alternative approaches: a simple eco‐hydrological method (coupled water‐energy budget (ECH)), elasticity‐based analysis (Budyko framework (EBA)), and a process‐based watershed model based on the Soil and Water Assessment Tool (SWAT). The efficiency of these approaches was assessed over the periods 1985–1994, 1995–2014, and under five potential near‐future human activities/climate change scenarios (S1–S5) by 2030. The results indicated that the climate change impacts on river flow was more severe than those of human activities. Climate change contributed to an average of 83.6% and 77.0% reduction in river flow in the past and the realistic future scenarios (i.e., S4 and S5), respectively, while human activities accounted for 16.4% and 30%. According to our findings, despite the fact that ECH results are more in line with the SWAT model, in case of physical characterization inaccessibility, ECH and EBA (as simple descriptive and quantitative models, respectively) can be used to separate, simulate and project the impacts of human activities and climate changes on river flow.
Growth factor‐loaded microspheres in mPEG‐polypeptide hydrogel system for articular cartilage repair
Authors: Lin Shih‐Jie , Chan Yun‐Chen , Su Zih‐Cheng , Yeh Wen‐Ling , Lai Po‐Liang , Chu I‐Ming
Published: July 2021

We developed an injectable hydrogel system with a sustained release of TGF‐β3 through growth factor‐loaded microsphere to mimic the cartilage‐like microenvironment. Poly(lactic‐co‐glycolic acid) (PLGA) microspheres incorporated in three dimensional (3D) scaffolds were chosen because of its regulatory approval, good biodegradability, and acting as carriers with sustained release behavior. We evaluated sustained release of TGF‐β3 by PLGA microspheres encapsulated in methoxy poly(ethylene glycol)‐poly(alanine) (mPA) hydrogels and the resulting enhanced chondrogenic effects. We reported here the effect of the proposed system for sustained release of growth factors on chondrogenesis in cartilage regeneration. PLGA microspheres were used in our thermosensitive mPA hydrogel system with bovine serum albumin as a stabilizing and protecting agent for the emulsion and TGF‐β3 enabling sustained release. Gelation, structural properties, and in‐vitro release of this composite, that is, microspheres in hydrogel, system were investigated. Using PLGA microspheres to carry growth factors could complement the mPA hydrogel's ability to provide an excellent 3D microenvironment for the promotion of chondrogenic phenotype as compared the systems using mPA hydrogel or microspheres alone. Our study demonstrated that this synthesized composite hydrogel system is capable of modulating the biosynthetic and differentiation activities of chondrocytes. The sustained release of TGF‐β3 in this novel hydrogel system could improve biomedical applicability of mPEG‐polypeptide scaffolds. The distinctive local growth factor delivery system successfully combined the use of both polymers to be a suitable candidate for prolonged articular cartilage regeneration.