bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Multicomponent MoVSbNbCeOx/SiO2 Catalyst with Enhanced Catalytic Activity for Oxidative Dehydrogenation of Ethane to Ethylene
Authors: Zenkovets Galina A. , Shutilov Alexey A. , Bondareva Valentina M. , Sobolev Vladimir I. , Marchuk Alexander S. , Tsybulya Sergey V. , Prosvirin Igor P. , Ishchenko Arcady V. , Gavrilov Vladimir Yu. 
Published: May 2020

AbstractIn our study, we have obtained a multicomponent MoVSbNbCeOx/SiO2 catalyst with high catalytic activity for oxidative dehydrogenation of ethane (ODE) to ethylene. To date, multicomponent MoVTe(Sb)NbOx catalysts, which have been intensively studied during the last years, were found as very promising for the ODE to produce ethylene. It was generally agreed that the MoVTeNbOx catalyst was more efficient than MoVSbNbOx. The major drawback of using Te‐containing catalysts is the presence of environmentally harmful, toxic tellurium, and its volatility during the catalyst preparation and catalytic reaction conditions. In our work, the Mo1V0.24Sb0.23Nb0.08Ce0.01Ox/50 wt. % SiO2 catalyst was prepared via the spray‐dry method of aqueous solutions of the starting components, followed by heat‐treatment in He at 350 and 600 °C. For comparative purpose, one of the best Te‐containing catalysts Mo1V0.3Te0.23Nb0.12Ox was also tested in this reaction under the similar reaction conditions. A comparison of the catalytic properties of Sb− and Te− containing catalysts at the reaction temperature of 400–450 °C illustrates for both catalysts relatively high catalytic properties for ODE. The yield of ethylene of ca. 74 % was obtained for these catalysts, which exceeds the best yield reported in literature for Sb‐containing catalysts. The two main phases – M1 and M2 were revealed by XRD in the Sb‐containing catalyst. Intergrowth between the crystals of M1 and M2 phases with the formation of the interphase boundary in the highly active and selective Sb‐containing catalyst can be proposed from HRTEM results. The nature of the active state in this catalyst is discussed.
A Supramolecular Model for the Co‐Catalytic Role of Nitro Compounds in Brønsted Acid Catalyzed Reactions
Authors: Montalvo‐Acosta Joel J. , Dryzhakov Marian , Richmond Edward , Cecchini Marco , Moran Joseph 
Published: May 2020

AbstractNitro compounds are known to change reaction rates and kinetic concentration dependence of Brønsted‐acid‐catalyzed reactions. Yet, no mechanistic model exists to account for these observations. In this work, an atomistic model for the catalytically active form for an alcohol dehydroazidation reaction is presented, which is generated by DFT calculations and consists of an H‐bonded aggregate of two molecules of Brønsted acid and two molecules of nitro compound. The computed O−H stretching frequencies for the aggregate indicate they are stronger acids than the individual acid molecules and serve as predictors for experimental reaction rates. By applying the model to a chemically diverse set of potential promoters, it was predicted and verified experimentally that sulfate esters induce a similar co‐catalytic effect. The important implication is that Brønsted‐acid catalysis must be viewed from a supramolecular perspective that accounts for not only the pKa of the acid and the bulk properties of a solvent, but also the weak interactions between all molecules in solution.
Modulation of the Self‐Assembly of π‐Amphiphiles in Water from Enthalpy‐ to Entropy‐Driven by Enwrapping Substituents
Authors: Syamala Pradeep P. N. , Würthner Frank 
Published: May 2020

AbstractDepending on the connectivity of solubilizing oligoethylene glycol (OEG) side chains to the π‐cores of amphiphilic naphthalene and perylene bisimide dyes, self‐assembly in water occurs either upon heating or cooling. Herein, we show that this effect originates from differences in the enwrapping capability of the π‐cores by the OEG chains. Rylene bisimides bearing phenyl substituents with three OEG chains attached directly to the hydrophobic π‐cores are strongly sequestered by the OEG chains. These molecules self‐assemble at elevated temperatures in an entropy‐driven process according to temperature‐ and concentration‐dependent UV/Vis spectroscopy and calorimetric dilution studies. In contrast, for rylene bisimides in which phenyl substituents with three OEG chains are attached via a methylene spacer, leading to much weaker sequestration, self‐assembly originates upon cooling in an enthalpy‐driven process. Our explanation for this controversial behavior is that the aggregation in the latter case is dictated by the release of “high energy water” from the hydrophobic π‐surfaces as well as dispersion interactions between the π‐scaffolds which drive the self‐assembly in an enthalpically driven process. In contrast, for the former case we suggest that in addition to the conventional explanation of a dehydration of hydrogen‐bonded water molecules from OEG units it is in particular the increase in conformational entropy of back‐folded OEG side chains upon aggregation that provides the pronounced gain in entropy that drives the aggregation process. Thus, our studies revealed that a subtle change in the attachment of solubilizing substituents can switch the thermodynamic signature for the self‐assembly of amphiphilic dyes in water from enthalpy‐ to entropy‐driven.
Short Total Synthesis of Ajoene, (E,Z)‐4,5,9‐Trithiadodeca‐1,6,11‐triene 9‐oxide, in Batch and (E,Z)‐4,5,9‐Trithiadodeca‐1,7,11‐triene in Continuous Flow
Authors: Raynbird Marina Yamamoto , Silva Filipa , Smallman Harry , Khokhar Shaista S. , Neef Daniel , Evans Gareth J. S. , Wirth Thomas 
Published: May 2020

AbstractA short total synthesis of ajoene, (E,Z)‐4,5,9‐trithiadodeca‐1,6,11‐triene 9‐oxide, has been achieved over six steps. In addition, a continuous flow synthesis under mild reaction conditions to (E,Z)‐4,5,9‐trithiadodeca‐1,7,11‐triene is described starting from simple and easily accessible starting materials. Over four steps including propargylation, radical addition of thioacetate, deprotection, and disulfide formation/ allylation, the target product can be obtained at a rate of 0.26 g h−1 in an overall yield of 12 %.
Thiophene and Selenophene Binding at a Pd3 Cluster Site
Authors: Yamamoto Koji , Sawada Junya , Murahashi Tetsuro 
Published: May 2020

AbstractWe report the triply bridging coordination of thiophene and selenophene to a trinuclear metal cluster site. The triply bridging coordination of selenophene at a Pd3 site forms a unique spiro‐type Pd5 cluster. Furthermore, either thiophene or selenophene is accommodated stably at a Pd3 site supported by a backside μ3‐cyclooctatetraene ligand through the face‐capping μ3‐coordination. The Pd3 site supported by the cyclooctatetraene ligand showed higher binding affinity of benzene over thiophene, although a Pd2 site strongly favors thiophene over benzene.
Calculating the Reaction Order and Activation Energy for the Hydrothermal Carbonization of Fructose
Authors: Jung Dennis , Körner Paul , Kruse Andrea 
Published: May 2020

AbstractThe development of accurate kinetic models for hydrothermal carbonization (HTC) faces major difficulties. This is related to the fact that the formation of the solid hydrochar can be regarded as a formation of a second phase from a homogenous solution. The reaction mechanism is not fully understood. From the current state of art, it is obvious that the reaction mechanism is some sort of polymerization reaction, thus, having reaction order higher than one. In order to gain more knowledge about the HTC reaction, fructose is used as a model substance, as it can be regarded as a key intermediate during the hydrothermal processing of carbohydrates. The results indicate that the reaction order is a highly sensitive parameter varying with temperature, reaction time and initial concentration. It can be concluded that the model itself is a strong simplification of the real reaction mechanism, thus more research is necessary to complete the actual knowledge.
Spectrum of driver mutations and clinical impact of circulating tumor DNA analysis in non–small cell lung cancer: Analysis of over 8000 cases
Authors: Mack Philip C. , Banks Kimberly C. , Espenschied Carin R. , Burich Rebekah A. , Zill Oliver A. , Lee Christine E. , Riess Jonathan W. , Mortimer Stefanie A. , Talasaz AmirAli , Lanman Richard B. , Gandara David R. 
Published: May 2020

BackgroundCirculating cell‐free tumor DNA (ctDNA)‐based mutation profiling, if sufficiently sensitive and comprehensive, can efficiently identify genomic targets in advanced lung adenocarcinoma. Therefore, the authors investigated the accuracy and clinical utility of a commercially available digital next‐generation sequencing platform in a large series of patients with non–small cell lung cancer (NSCLC).MethodsPlasma‐based comprehensive genomic profiling results from 8388 consecutively tested patients with advanced NSCLC were analyzed. Driver and resistance mutations were examined with regard to their distribution, frequency, co‐occurrence, and mutual exclusivity.ResultsSomatic alterations were detected in 86% of samples. The median variant allele fraction was 0.43% (range, 0.03%‐97.62%). Activating alterations in actionable oncogenes were identified in 48% of patients, includingEGFR(26.4%),MET(6.1%), andBRAF(2.8%) alterations and fusions (ALK,RET, andROS1) in 2.3%. Treatment‐induced resistance mutations were common in this cohort, including driver‐dependent and driver‐independent alterations. In the subset of patients who had progressive disease duringEGFRtherapy, 64% had known or putative resistance alterations detected in plasma. Subset analysis revealed that ctDNA increased the identification of driver mutations by 65% over standard‐of‐care, tissue‐based testing at diagnosis. A pooled data analysis on this plasma‐based assay demonstrated that targeted therapy response rates were equivalent to those reported from tissue analysis.ConclusionsComprehensive ctDNA analysis detected the presence of therapeutically targetable driver and resistance mutations at the frequencies and distributions predicted for the study population. These findings add support for comprehensive ctDNA testing in patients who are incompletely tested at the time of diagnosis and as a primary option at the time of progression on targeted therapies.
Early information needs of adolescents and young adults about late effects of cancer treatment
Authors: Greenzang Katie A. , Fasciano Karen M. , Block Susan D. , Mack Jennifer W. 
Published: May 2020

BackgroundAdolescent and young adult (AYA) cancer survivors have high risks of late effects. Little is known about the late‐effect information needs of AYAs early in treatment or their role in treatment decision making. This study evaluated the importance, quality, and implications of information about late effects in AYAs recently diagnosed with cancer.MethodsThis study surveyed 201 AYAs with cancer who were 15 to 29 years old and were treated at the Dana‐Farber Cancer Institute (Boston, Massachusetts). Patients were approached within 6 weeks of their diagnosis and were asked about their late‐effect and infertility information needs, treatment decision making, and communication outcomes.ResultsForty‐five percent of the participants were female; 88% were white. Most AYAs (87% [173 of 200]) considered information about the risks of late effects to be extremely or very important; 80% (159 of 200) valued information about infertility. Many were distressed by information about late effects (53% [105 of 200]) and infertility (45% [89 of 200]); those who considered late‐effect information distressing were more likely to value this information (P < .0001). Consideration of late effects (41% [82 of 201]) and infertility (36% [72 of 201]) greatly influenced many patients' treatment decision making. Although 92% of the patients (184 of 199) reported receiving high‐quality information about the diagnosis, 57% (113 of 199; P < .0001) and 65% (130 of 199; P < .0001) felt that they had received high‐quality information about late effects and infertility, respectively.ConclusionsMost AYAs with cancer value early information about the risks of late effects and infertility, yet many patients felt that they had not received high‐quality information about these topics. The development of age‐appropriate late‐effect communication strategies that recognize high AYA distress may help to address the gap between desired information and perceived information quality.
Effects of Solid Electrolyte Interphase Components on the Reduction of LiFSI over Lithium Metal
Authors: Kamphaus Ethan P. , Gomez Stefany Angarita , Qin Xueping , Shao Minhua , Balbuena Perla B. 
Published: May 2020

AbstractThe use of a lithium metal anode still presents a challenging chemistry and engineering problem that holds back next generation lithium battery technology. One of the issues facing lithium metal is the presence of the solid electrolyte interphase (SEI) layer that forms on the electrode creating a variety of chemical species that change the properties of the electrode and is closely related to the formation and growth of lithium dendrites. In order to advance the scientific progress of lithium metal more must be understood about the fundamentals of the SEI. One property of the SEI that is particularly critical is the passivating behavior of the different SEI components. This property is critical to the continued formation of SEI and stability of the electrolyte and electrode. Here we report the investigation of the passivation behavior of Li2O, Li2CO3, LiF and LiOH with the lithium salt LiFSI. We used large computational chemistry models that are able to capture the lithium/SEI interface as well as the SEI/electrolyte interface. We determined that LiF and Li2CO3 are the most passivating of the SEI layers, followed by LiOH and Li2O. These results match previous studies of other Li salts and provide further examination of LiFSI reduction.
A Novel 3D Petal‐Like SnS2 Hierarchical Structure with Superior Photocatalytic Hydrogen Production Ability
Authors: Ding Yifan , Liu Shengqian , Li Jun , Qi Xiang 
Published: May 2020

AbstractHerein, a novel 3D petal‐like SnS2 hierarchical structure is successfully prepared by a simple hydrothermal method. The as‐prepared samples are characterized by X‐ray diffraction and scanning electron microscopy. UV–vis spectra exhibit an absorption edge of ≈635 nm. Photoelectrochemical measurements demonstrate that the photocurrent density can be effectively increased from 0.04 to 1.10 μA cm−2 with applied bias potential range from 0.1 to 1.0 V. Additionally, there is no significant decay of photocurrent density after 60 cycles. Its remarkable performance and excellent stability in photocatalytic hydrogen evolution can be attributed to the huge specific surface area, unique hierarchical structure of petals, and high charge separation efficiency. Based on these results, a conclusion can be drawn that the novel 3D petal‐like SnS2 hierarchical structure will have a good development prospect in the future.
Layered Crystal Structural Entecavir Monohydrate: Prepared in Pure Water and Calculated by DFT
Authors: Kang Yanlei , Yu Dongdong , Miao Haoyu , Cheng Jianbo , Yu Xiaofeng , Zhou Jianguang 
Published: May 2020

AbstractEntecavir (ETV) is approved by the Food and Drug Administration for the treatment of chronic hepatitis B in 2005. ETV monohydrate (ETV‐H) is used as drug substance in pharmaceutical industry. In this work, ETV‐H is prepared in pure water. The single crystal structure of ETV‐H is originally reported by Jiang and Liu in 2009 and shows a layered structure in ETV‐H crystal. Then ETV‐H is first studied by density functional theory method at B3LYP/6‐311+G(d,p) level. The optimized geometric parameters of ETV‐H agree well with the reported single crystal data and theoretical vibrational frequencies are consistent with experimental spectra. Molecular electronic potential and natural bond orbital results exhibit the molecular connection properties of the layered structure. The theoretical calculated dihedral angles between two ETV molecules are 177.6° and 176.8°, indicating that two ETV molecules are almost in the same plane. The theoretical calculated interlayer space is 16.4 Å, which is similar to the calculated interlayer space 16.7 Å using X‐ray diffraction result according to Bragg's law. These calculated results further illustrate the existence of the layered structure in ETV‐H crystal. This study may provide an idea for the future drug research.
EGFR‐targeted CAR‐T cells are potent and specific in suppressing triple‐negative breast cancer both in vitro and in vivo
Authors: Xia Lin , Zheng Zao‐zao , Liu Jun‐yi , Chen Yu‐jie , Ding Jian‐cheng , Xia Ning‐shao , Luo Wen‐xin , Liu Wen 
Published: May 2020

AbstractObjectivesTriple‐negative breast cancer (TNBC) is well known for its strong invasiveness, rapid recurrence and poor prognosis. Immunotherapy, including chimeric antigen receptor‐modified T (CAR‐T) cells, has emerged as a promising tool to treat TNBC. The identification of a specific target tumor antigen and the design of an effective CAR are among the many challenges of CAR‐T therapy.MethodsWe reported that epidermal growth factor receptor (EGFR) is highly expressed in TNBC and consequently designed an optimal third generation of CAR targeting EGFR. The efficacy of primary T lymphocytes infected with EGFR CAR lentivirus (EGFR CAR‐T) against TNBC was evaluated both in vitro and in vivo. The signalling pathways activated in tumor and EGFR CAR‐T cells were revealed by RNA sequencing analysis.ResultsThird‐generation EGFR CAR‐T cells exerted potent and specific suppression of TNBC cell growth in vitro, whereas limited cytotoxicity was observed towards normal breast epithelial cells or oestrogen receptor‐positive breast cancer cells. This capability was further demonstrated in vivo in a xenograft mouse model, with minimal off‐tumor cytotoxicity. Mechanistically, in vitro stimulation with TNBC cells induced the expansion of naïve‐associated EGFR CAR‐T cells and enhanced their persistence. Furthermore, EGFR CAR‐T cells activated the interferon γ, granzyme–perforin–PARP and Fas–FADD–caspase signalling pathways in TNBC cells.ConclusionWe demonstrate that EGFR is a relevant immunotherapeutic target in TNBC, and EGFR CAR‐T exhibits potent and specific antitumor activity against TNBC, suggesting the potential of this third‐generation EGFR CAR‐T as an immunotherapy tool to treat TNBC in the clinic.
A case of metastatic rectal adenocarcinoma diagnosed by thyroid cytology
Authors: Sakaleshpura Mallikarjunappa Subramanya , Valluru Neelima , Park Ji‐Weon , Gattuso Paolo , Cheng Lin 
Published: May 2020

AbstractFine‐needle aspiration (FNA) cytology of the thyroid gland has been widely used for the evaluation of thyroid nodules. Most of the nodules are primary thyroid lesions. However, up to 4% of thyroid FNA may harbor a metastatic neoplasm. The metastases are most commonly from lung, kidney, breast, and skin. Metastatic colorectal cancers are also seen in thyroid but less common. Here we report the cytologic features, differential diagnosis and clinical implications of a metastatic rectal adenocarcinoma to the thyroid gland diagnosed by FNA.
Ensuring identifiability in hierarchical mixed effects Bayesian models
Authors: Ogle Kiona , Barber Jarrett J. 
Published: May 2020

AbstractEcologists are increasingly familiar with Bayesian statistical modeling and its associated Markov chain Monte Carlo (MCMC) methodology to infer about or to discover interesting effects in data. The complexity of ecological data often suggests implementation of (statistical) models with a commensurately rich structure of effects, including crossed or nested (i.e., hierarchical or multi‐level) structures of fixed and/or random effects. Yet, our experience suggests that most ecologists are not familiar with subtle but important problems that often arise with such models and with their implementation in popular software. Of foremost consideration for us is the notion of effect identifiability, which generally concerns how well data, models, or implementation approaches inform about, i.e., identify, quantities of interest. In this paper, we focus on implementation pitfalls that potentially misinform subsequent inference, despite otherwise informative data and models. We illustrate the aforementioned issues using random effects regressions on synthetic data. We show how to diagnose identifiability issues and how to remediate these issues with model reparameterization and computational and/or coding practices in popular software, with a focus on JAGS, OpenBUGS, and Stan. We also show how these solutions can be extended to more complex models involving multiple groups of nested, crossed, additive, or multiplicative effects, for models involving random and/or fixed effects. Finally, we provide example code (JAGS/OpenBUGS and Stan) that practitioners can modify and use for their own applications.
FloraSNevada: a trait database of the vascular flora of Sierra Nevada, southeast Spain
Authors: Lorite Juan , Ros‐Candeira Andrea , Alcaraz‐Segura Domingo , Salazar‐Mendías Carlos 
Published: May 2020

AbstractProviding a complete data set with species and trait information for a given area is essential for assessing plant conservation, management, and ecological restoration, for both local and global applications. Also, these data sets provide additional information for surveys or data collections, establishing the starting point for more detailed studies on plant evolution, vegetation dynamics, and vegetation responses to disturbance and management. This data base covers Sierra Nevada mountains (southeastern Spain), a recognized plant biodiversity hotspot within the Mediterranean context. According to previous available data (before this augmented compilation), these mountains host 7% of the 24,000 Mediterranean vascular plants, despite covering just 0.01% of its area. Another characteristic of the Sierra Nevada is the great singularity of its flora, with 95 taxa being endemic to the high‐mountain area of Sierra Nevada and surroundings. From these endemic taxa, 70% are endangered by different threats, global warming being a leading cause. We seek to provide a complete and updated database of the flora of the Sierra Nevada mountains (southeast Spain). The goal of the present data set is to compile the names of all the vascular plant taxa inhabiting Sierra Nevada, together with relevant features including taxonomical, morphological–ecological traits, distribution, habitats, abundance, and conservation status. The data were compiled according to all the available information sources on taxonomy, ecology, and plant‐species distribution. The resulting data set includes 2,348 taxa belonging to 1,937 species, 377 subspecies, and 34 hybrids, from a total of 756 genera and 146 families represented in the collection. For each taxa, together with taxonomical information (Phylum, Class, Family, Genus, Taxa), we compiled plant traits (life form, spinescence, flower symmetry, flower sexuality, plant gender, androecium:ginoecium ratio, flower color, perianth type, pollinator type, flowering, seed dispersal, and vegetative reproduction), and their environmental association (origin, endemic character, general distribution, substrate, elevation, habitat, local abundance, hygrophilous behavior, and conservation status). All these traits were compiled from all the available information sources, resulting in a complete and updated database for Sierra Nevada vascular flora. This data set provides valuable information on plant traits in an outstanding micro hotspot within the Mediterranean hotspot. This data set can be freely used for noncommercial purposes. This data set is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0). When you use this data set, we request that you cite the data and this data paper.