bluuebunny/crossref_metadata_2025_split huggingface dataset:
Palladium‐Catalysed C−H Bond Zincation of Arenes: Scope, Mechanism, and the Role of Heterometallic Intermediates
Authors: Garçon Martí , Mun Nicolette Wee , White Andrew J. P. , Crimmin Mark R. 
Published: December 2020

AbstractCatalytic methods that transform C−H bonds into C−X bonds are of paramount importance in synthesis. A particular focus has been the generation of organoboranes, organosilanes and organostannanes from simple hydrocarbons (X=B, Si, Sn). Despite the importance of organozinc compounds (X=Zn), their synthesis by the catalytic functionalisation of C−H bonds remains unknown. Herein, we show that a palladium catalyst and zinc hydride reagent can be used to transform C−H bonds into C−Zn bonds. The new catalytic C−H zincation protocol has been applied to a variety of arenes—including fluoroarenes, heteroarenes, and benzene—with high chemo‐ and regioselectivity. A mechanistic study shows that heterometallic Pd–Zn complexes play a key role in catalysis. The conclusions of this work are twofold; the first is that valuable organozinc compounds are finally accessible by catalytic C−H functionalisation, the second is that heterometallic complexes are intimately involved in bond‐making and bond‐breaking steps of C−H functionalisation.
Ti–Mn coating prepared by tungsten inert gas cladding and its inhibiting coking property
Authors: Li Jingpeng , Yu Xiaochun , Wang Runqiu , Wang Zhiyuan , Wang Laizhi , Zhou Jianxin 
Published: December 2020

AbstractThe Ti–Mn cladding layers with different ratios were prepared on the surface of 310S steel using tungsten inert gas (TIG) technology for inhibiting coking in ethylene cracking, and the cladding specimens were oxidized by muffle furnace for 10 h at 800°C. The coking evaluation tests of the oxidized specimens with different Ti–Mn powder ratios were carried out with light naphtha at 850°C. The results show that when the ratio of Ti to Mn was 3:1, a protective layer of TiO2–TinO2n‐1–Mn5O8 was formed on the surface of specimen, and with the decrease of Ti element content, unstable Fe‐Ti spinel compounds appeared on the surface. When the ratio of Ti to Mn is 1:3, 1:2, and 1:1, the coking inhibition rate was 40%, 46%, and 59%, respectively. Catalytic coke formed on the surface of coating. When the ratio of Ti to Mn was 3:1, the inhibiting coking rate on the surface of the coating reached 80%, and the inhibiting coking performance was optimal, which inhibited the catalytic coking of Fe and Ni metal particles. With the increase of Ti content and the decrease of Mn content, the graphitization degree of coke decreased according to Raman spectrum.
Practical two‐step chain extension method to prepare sulfonated waterborne polyurethanes based on aliphatic diamine sulphonate
Authors: Mou Jing , Wang Xiaojun , Yu Dongmei , Wang Shengpeng , Miao Yulong , Liu Qin , Chen Bajin 
Published: December 2020

AbstractWe reported a novel synthesis route to fabricate sulfonated aliphatic waterborne polyurethane dispersions (SWPU) only based on 2‐[(2‐aminoethyl) amino] ethane sulphonate sodium (AAS‐Na) by two‐step chain extension method with the assistance of acetone and water cosolvent. When AAS‐Na was added, only less than 50% of AAS‐Na was incorporated into polyurethane chain in the first‐step chain extension and the residual AAS‐Na formed molecular aggregates which were insoluble in acetone due to the high polarity of AAS‐Na. Subsequently, the mixture of acetone and water was added, the residual AAS‐Na aggregates dissolved, undertaking the further second‐step chain extension reaction, and the ultimate reaction conversion of AAS‐Na rose to more than 90%. The mechanism for acetone and water cosolvent to affect the preparation of SWPU dispersions was studied, as well as the water resistance, mechanical properties and hydrolysis resistance of as‐prepared SWPU dispersions. With the decrease of AAS‐Na content from 2.0% to 1.2%, the peak area of the melting peaks for SWPU films increased, as well as the water resistance. And the as‐prepared polyester SWPU exhibited good hydrolytic stability.
Priors Bias Perceptual Decisions in Autism, But Are Less Flexibly Adjusted to the Context
Authors: Sapey‐Triomphe Laurie‐Anne , Timmermans Laura , Wagemans Johan 
Published: December 2020

AbstractAccording to the predictive coding framework, percepts emerge from combinations of sensory input and prior knowledge, whose relative contributions depend on their reliability. Recent predictive coding theories suggest that Autism Spectrum Disorder (ASD) could be characterized by an atypical weighting of priors. Here, we assessed whether individuals with ASD can flexibly adjust the weight (precision) of the prior to the context. Thirty‐one neurotypical adults (NT) and 26 adults with ASD participated in a visual discrimination task designed to elicit a time‐order effect (TOE). The TOE reflects the integration of priors with sensory estimates. We used two experimental contexts: a narrow stimulus range (Narrow condition) and a broader range (Broad condition) in order to induce a prior with a higher and lower precision, respectively. Both groups learned a prior that biased their perception, as shown with the TOE. As expected, the NT group had a larger TOE in the Narrow condition than in the Broad condition, revealing a contextual adjustment of the prior precision. In contrast, ASD participants were more inflexible: the extent of the TOE was not modulated by the context. In addition, the accuracy increased when the stimulus range decreased in both group, which may be interpreted as a contextual adjustment of the sensory precision. To conclude, adults with and without ASD implicitly learned a prior mean, but ASD participants failed to flexibly adjust the prior precision to the context. This increased inflexibility in ASD could account for many symptoms, such as their intolerance of uncertainty.Lay SummaryBased on our experience, we have expectations about our environment. Theories suggest that the symptoms encountered in autism could be due to atypical expectations, leading to an impression of an unpredictable world. Using a visual discrimination task, we showed that adults with and without autism were biased by their expectations. Yet, the extent to which expectations biased perception did not depend on the context in autism. This higher inflexibility found in autism may explain symptoms such as resistance to change.
Laser Patterning of High‐Mass‐Loading Graphite Anodes for High‐Performance Li‐Ion Batteries
Authors: Dubey Romain , Zwahlen Marcel‐David , Shynkarenko Yevhen , Yakunin Sergii , Fuerst Axel , Kovalenko Maksym V. , Kravchyk Kostiantyn V. 
Published: December 2020

AbstractGiven the ongoing efforts to build Li‐ion batteries with higher volumetric energy and power densities, the research on enhancing Li‐ion transport within compressed high‐mass‐loading electrodes at fast cycling conditions is imperative. In this work, we show that the rate capability of graphite electrodes with high areal capacity of 4.5 mAh cm−2 and density of 1.79 g cm−3 (15 % of porosity) can be considerably improved by laser patterning, namely by the fabrication of arrays of vertically aligned channels serving as diffusion paths for rapid Li‐ion transport. Resultant laser patterned graphite electrodes delivered enhanced volumetric capacity as compared to that of non‐patterned electrodes (450 vs. 396 mAh cm−3 at C/2 rate). The reduction of the total steady‐state concentration drop within the graphite electrodes after their patterning was also assessed.
RNA‐protein interactions: Central players in coordination of regulatory networks
Authors: Armaos Alexandros , Zacco Elsa , Sanchez de Groot Natalia , Tartaglia Gian Gaetano 
Published: December 2020

AbstractChanges in the abundance of protein and RNA molecules can impair the formation of complexes in the cell leading to toxicity and death. Here we exploit the information contained in protein, RNA and DNA interaction networks to provide a comprehensive view of the regulation layers controlling the concentration‐dependent formation of assemblies in the cell. We present the emerging concept that RNAs can act as scaffolds to promote the formation ribonucleoprotein complexes and coordinate the post‐transcriptional layer of gene regulation. We describe the structural and interaction network properties that characterize the ability of protein and RNA molecules to interact and phase separate in liquid‐like compartments. Finally, we show that presence of structurally disordered regions in proteins correlate with the propensity to undergo liquid‐to‐solid phase transitions and cause human diseases. Also see the video abstract here https://youtu.be/kfpqibsNfS0
Macroscopic modeling of bioreactors for recombinant protein producingPichia pastorisin defined medium
Authors: Hong Moo Sun , Velez‐Suberbie M. Lourdes , Maloney Andrew J. , Biedermann Andrew , Love Kerry R. , Love J. Christopher , Mukhopadhyay Tarit K. , Braatz Richard D. 
Published: December 2020

AbstractThe methylotrophic yeastPichia pastorisis widely used as a microbial host for recombinant protein production. Bioreactor models forP. pastoriscan inform understanding of cellular metabolism and can be used to optimize bioreactor operation. This article constructs an extensive macroscopic bioreactor model forP. pastoriswhich describes substrates, biomass, total protein, other medium components, and off‐gas components. Species and elemental balances are introduced to describe uptake and evolution rates for medium components and off‐gas components. Additionally, a pH model is constructed using an overall charge balance, acid/base equilibria, and activity coefficients to describe production of recombinant protein and precipitation of medium components. The extent of run‐to‐run variability is modeled by distributions of a subset of the model parameters, which are estimated using the maximum likelihood method. Model prediction from the extensive macroscopic bioreactor model well describes experimental data with different operating conditions. The probability distributions of the model predictions quantified from the parameter distribution are quantifiably consistent with the run‐to‐run variability observed in the experimental data. The uncertainty description in this macroscopic bioreactor model identifies the model parameters that have large variability and provides guidance as to which aspects of cellular metabolism should be the focus of additional experimental studies. The model for medium components with pH and precipitation can be used for improving chemically defined medium by minimizing the amount of components needed while meeting cellular requirements.
Der Mann aus dem Eis
Authors: Zink Albert 
Published: December 2020

ZusammenfassungSeit seiner Entdeckung in den Ötztaler Alpen am 19. September 1991 gewährt uns der Mann aus dem Eis einen tiefen Einblick in die Lebensumstände einer bis dahin wenig erforschten Bevölkerung, die vor über 5000 Jahren im alpinen Raum heimisch war. Durch die Verwendung modernster medizinischer und naturwissenschaftlicher Untersuchungen ist es gelungen, zahllose Details über das Leben der weltbekannten Gletschermumie, aber vor allem auch zu ihren Krankheiten und zu ihrem gewaltsamen Tod am Hauslabjoch zu erforschen. Darüber hinaus bietet die moderne Mumienforschung die Möglichkeit, wichtige Erkenntnisse zum Auftreten und zur Entwicklung von Krankheiten zu erhalten. So konnten bei dem Mann aus dem Eis, mit Hilfe von modernen Hochdurchsatzsequenzierverfahren, eine genetische Veranlagung für Herz‐ und Kreislauferkrankungen festgestellt und der Krankheitserreger Helicobacter pylori im Magen des Ötzi nachgewiesen werden. Die Untersuchung unterschiedlicher Biomoleküle, einschließlich DNA, Lipiden und Proteinen, ermöglichte zudem die Rekonstruktion seiner letzten Mahlzeit, die im Wesentlichen aus getrocknetem und sehr fettreichem Wildfleisch und frühen Getreidearten wie dem Einkorn bestand.
An assay for cancer stem cell‐induced angiogenesis on chick chorioallantoic membrane
Authors: Nawara Hend M. , Afify Said M. , Hassan Ghmkin , Zahra Maram H. , Atallah Marwa N. , Seno Akimasa , Seno Masaharu 
Published: December 2020

AbstractAngiogenesis is generally involved in tumor growth and metastasis. Cancer stem cells (CSCs) are considered to facilitate the angiogenesis. Therefore, CSCs could be the effective targets to stop angiogenesis. Recently, our group successfully generated CSC models from induced pluripotent stem cells (iPSCs) in the presence of conditioned medium derived from cancer derived cells. These novel model CSCs has been characterized by highly tumorigenic, angiogenic and metastatic potentials in vivo. The angiogenic potential of CSCs has been explained by the expression of both angiogenic factors and their receptors implying the angiogenesis in autocrine manner. In this protocol we optimized the method to evaluate tumor angiogenesis with the CSC model, which was described effective to assess sorafenib as an antiangiogenic drug, on chick chorioallantoic membrane (CAM) assay. Our results demonstrate that CSCs developed from iPSCs and CAM assay are a robust and cost‐effective tool to evaluate tumor angiogenesis with CSCs. Collectively, CSCs in CAM assay could serve as a very useful model for the screening of potential therapeutic agents targeting tumor angiogenesis.
Numerical Deconvolution of Surface Interrogation Scanning Electrochemical Microscopy Experiments on Platinum During Hydrogen Evolution
Authors: Jantz Dylan T. , Seuferling Tess E. , Leonard Kevin C. 
Published: December 2020

AbstractInvited for this month's cover picture is the group of Prof. Kevin C. Leonard. The cover picture shows an artistic rendition of a surface interrogation scanning electrochemical microscopy experiment in the act of gathering fundamental insights into the adsorbed intermediates on an electrode surface during an electrocatalytic reaction. Read the full text of the Article at 10.1002/celc.202001082.
Effect of Transition Metals on the Oxygen Reduction Reaction Activity at Metal‐N3/C Active Sites
Authors: Fruehwald Holly M. , Ebralidze Iraklii I. , Zenkina Olena V. , Easton E. Bradley 
Published: December 2020

AbstractInvited for this month's cover picture are the groups of Brad Easton and Olena Zenkina at Ontario Tech University (Canada). The cover picture shows an artistic dipcition of a treasure map quest for unique M‐N3 non‐platinum group metal fuel cell catalysts. Read the full text of the Article at 10.1002/celc.202000954.
Gold‐Based Pharmacophore Inhibits Intracellular MYC Protein
Authors: Ofori Samuel , Gukathasan Sailajah , Awuah Samuel G. 
Published: December 2020

AbstractDirect targeting of intrinsically disordered proteins, including MYC, by small molecules for biomedical applications would resolve a longstanding issue in chemical biology and medicine. Thus, we developed gold‐based small‐molecule MYC reagents that engage MYC inside cells and modulate MYC transcriptional activity. Lead compounds comprise an affinity ligand and a gold(I) or gold(III) warhead capable of protein chemical modification. Cell‐based MYC target engagement studies via CETSA and co‐immunoprecipitation reveal specific interaction of compounds with MYC in cells. The lead gold(I) reagent, 1, demonstrates superior cell‐killing potential (up to 35‐fold) in a MYC‐dependent manner when compared to 10058‐F4 in cells including the TNBC, MDA‐MB‐231. Subsequently, 1 suppresses MYC transcription factor activity via functional colorimetric assays, and gene‐profiling using whole‐cell transcriptomics reveals significant modulation of MYC target genes by 1. These findings point to metal‐mediated ligand affinity chemistry (MLAC) based on gold as a promising strategy to develop chemical probes and anticancer therapeutics targeting MYC.
Obesity, comorbidities, and treatment selection in Black and White women with early breast cancer
Authors: Nyrop Kirsten A. , Damone Emily M. , Deal Allison M. , Carey Lisa A. , Lorentsen Michael , Shachar Shlomit S. , Williams Grant W. , Brenizer Addison (Tucker) , Wheless Amy , Muss Hyman B. 
Published: December 2020

BackgroundThis study investigates obesity and comorbidity in Black and White women with early breast cancer (stages I‐III) and their potential impact on treatment decisions for patients with hormone receptor–positive (HR+)/human epidermal growth factor receptor 2–negative (HER2–) tumors.MethodsIn this retrospective chart review, comparisons of frequencies for Black and White patients were calculated with the Fisher exact test. Log binomial regression was used to estimate prevalence ratios (PRs) with 95% confidence intervals for total and individual comorbidities, and multivariable modeling was used to estimate PRs adjusted for age and body mass index (BMI).ResultsIn a sample of 548 patients, 26% were Black, and 74% were White. Sixty‐two percent of Black patients and 32% of White patients were obese (BMI ≥ 30 kg/m2; P < .0001). Seventy‐five percent of Black patients and 87% of White patients had HR+ tumors (P = .001). Significant intergroup differences were seen for 2 or more total comorbidities (62% of Blacks vs 47% of Whites; P = .001), 2 or more obesity‐related comorbidities (33% vs 10%; P < .0001), hypertension (60% vs 32%; P < .0001), diabetes mellitus (23% vs 6%; P < .0001), hypercholesterolemia or hyperlipidemia (28% vs 18%; P = .02), and hypothyroidism (4% vs 11%; P = .012). In women with HR+/HER2– tumors, there were no intergroup differences in treatment decisions regarding the type of surgery, chemotherapy regimen, radiation, or endocrine treatment despite significant differences in the prevalence of obesity and comorbidities.ConclusionsThis study documents significant disparities between Black and White women with early breast cancer with regard to high rates of obesity, overall comorbidities, and obesity‐related comorbidities, and it highlights the prevalence of competing risks that may complicate outcomes in breast cancer.
From Cd‐Rich to Se‐Rich – The Manipulation of CdSe Nanocluster Structure and Optical Absorption
Authors: Jäger Marc , Schäfer Rolf 
Published: December 2020

AbstractA combined experimental and quantum‐chemical study of the structure and optoelectronic properties of isolated non‐stoichiometric CdxSey+ clusters with x=3, 4 and y=3, 4 is presented. The consistency of optical response calculations with the measured absorption spectra reveals that the theoretically predicted lowest energy structural isomers have been formed in the molecular beam experiments. The Se‐rich nanocluster Cd3Se4+ contains a Se2− unit which is responsible for the enhanced light absorption in the visible spectral range. In contrast, the radical electron of the Cd‐rich species Cd4Se3+ is localized at a Cd+ centre which is attached to a six‐membered Cd3Se3 ring. The excess Cd atom is partly responsible for an intense optical absorption in the near ultraviolet. The variation of the geometry and the optical behaviour in dependence of the stoichiometry is discussed with respect to the photocatalytic properties of CdSe nanoparticles
Epigenetic consequences of hormonal interactions between opposite‐sex twin fetuses
Authors: Kong Siming , Peng Yong , Chen Wei , Ma Xinyi , Wei Yuan , Zhao Yangyu , Li Rong , Qiao Jie , Yan Liying 
Published: December 2020

AbstractPrevious studies reported inconsistent evidence about some phenotypic traits of females in human opposite‐sex twins (opposite‐sex females [OSF]) being distinct from females in same‐sex twins (SSF). Comparatively, less evidence showed significant differences between males in OS twins (opposite‐sex males [OSM]) and males in same‐sex twins (SSM). The twin testosterone transfer hypothesis suggests that prenatal exposure of testosterone in utero may be a possible explanation for the differential traits in OSF; however, the underlying mechanism is unknown. Here, we investigated the potential epigenetic effects of hormone interactions and their correlation to the observed phenotypic traits. In the study, DNA methylomic data from 54 newborn twins and histone modification data (H3K4me3, H3K4me1, H3K27me3, and H3K27ac) from 14 newborn twins, including same‐sex females (SSF), OS twins, and same‐sex males (SSM) were generated. We found that OSF were clearly distinguishable from SSF by DNA methylome, while OSM were distinguishable from SSM by H3K4me1 and H3K4me3. To be more specific, compared to SSF, OSF showed a stronger correlation to males (OSM and SSM) in genome‐wide DNA methylation. Further, the DNA methylomic differences between OSF and SSF were linked to the process involving cognitive functions and nervous system regulation. The differential H3K4me3 between OSM and SSM was linked to immune responses. These findings provide epigenetic evidence for the twin testosterone transfer hypothesis and offer novel insights on how prenatal hormone exposure in utero may be linked to the reported differential traits of OS twins.
An in vitro assay approach to investigate the potential impact of different doping agents on the steroid profile
Authors: Piper Thomas , Heimbach Sonja , Adamczewski Martin , Thevis Mario 
Published: December 2020

AbstractThe steroid profile, that is, the urinary concentrations and concentration ratios of selected steroids, is used in sports drug testing to detect the misuse of endogenous steroids such as testosterone. Since several years, not only population‐based thresholds are applied but also the steroid profile is monitored via the Athlete Biological Passport whereby the individual reference ranges derived from multiple test results of the same athlete are compared to population‐based thresholds. In order to maintain a high probative force of the passport, samples collected or analyzed under suboptimal conditions should not be included in the longitudinal review. This applies to biologically affected or degraded samples and to samples excluded owing to the presence of other substances potentially (or evidently) altering the steroid profile. Nineteen different doping agents comprising anabolic steroids, selective androgen receptor modulators, selective estrogen receptor modulators, ibutamoren, and tibolone were investigated for their effect on the steroid profile using an androgen receptor activation test, an androgen receptor binding assay, an aromatase assay, and a steroidogenesis assay. The in vitro tests were coupled with well‐established liquid chromatography/mass spectrometry‐based analytical approaches and for a subset of steroidal analytes by gas chromatography/mass spectrometry. The variety of tests employed should produce a comprehensive data set to better understand how a compound under investigation may impact the steroid profile. Although our data set may allow an estimate of whether or not a substance will have an impact on the overall steroid metabolism, predicting which parameter in particular may be influenced remains difficult.