bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clonal dynamics in pediatric B‐cell precursor acute lymphoblastic leukemia with very early relapse
Authors: Antić Željko , Yu Jiangyan , Bornhauser Beat C. , Lelieveld Stefan H. , van der Ham Cedric G. , van Reijmersdal Simon V. , Morgado Lionel , Elitzur Sarah , Bourquin Jean‐Pierre , Cazzaniga Giovanni , Eckert Cornelia , Camós Mireia , Sutton Rosemary , Cavé Hélène , Moorman Anthony V. , Sonneveld Edwin , Geurts van Kessel Ad , van Leeuwen Frank N. , Hoogerbrugge Peter M. , Waanders Esmé , Kuiper Roland P. 
Published: October 2021

AbstractIntroductionOne‐quarter of the relapses in children with B‐cell precursor acute lymphoblastic leukemia (BCP‐ALL) occur very early (within 18 months, before completion of treatment), and prognosis in these patients is worse compared to cases that relapse after treatment has ended.MethodsIn this study, we performed a genomic analysis of diagnosis–relapse pairs of 12 children who relapsed very early, followed by a deep‐sequencing validation of all identified mutations. In addition, we included one case with a good initial treatment response and on‐treatment relapse at the end of upfront therapy.ResultsWe observed a dynamic clonal evolution in all cases, with relapse almost exclusively originating from a subclone at diagnosis. We identified several driver mutations that may have influenced the outgrowth of a minor clone at diagnosis to become the major clone at relapse. For example, a minimal residual disease (MRD)‐based standard‐risk patient with ETV6‐RUNX1‐positive leukemia developed a relapse from a TP53‐mutated subclone after loss of the wildtype allele. Furthermore, two patients with TCF3‐PBX1‐positive leukemia that developed a very early relapse carried E1099K WHSC1 mutations at diagnosis, a hotspot mutation that was recurrently encountered in other very early TCF3‐PBX1‐positive leukemia relapses as well. In addition to alterations in known relapse drivers, we found two cases with truncating mutations in the cohesin gene RAD21.ConclusionComprehensive genomic characterization of diagnosis–relapse pairs shows that very early relapses in BCP‐ALL frequently arise from minor subclones at diagnosis. A detailed understanding of the therapeutic pressure driving these events may aid the development of improved therapies.
Tetramethyl guanidine‐assisted synthesis and thermal crosslinking of multifunctional benzoxazine monomers based on natural phloretic acid
Authors: Forchetti Casarino Agustin , Moreno Adrián , Galià Marina , Estenoz Diana A. , Lligadas Gerard , Spontón Marisa E. 
Published: October 2021

AbstractAn efficient strategy to synthesize novel biobased multifunctional benzoxazine compounds was developed using the 1,1,3,3‐tetramethyl guanidine (TMG)‐triggered esterification of natural phloretic acid with organic halides as a key synthetic step. First, phloretic acid was combined with either aniline or furfurylamine to prepare the corresponding carboxylic acid‐functional monobenzoxazine monomer. Next, the use of TMG enabled an efficient esterification of these compounds with di‐, tri‐, and tetra‐functional benzyl bromide compounds at room temperature to afford a series of new multi‐benzoxazine monomers tethered to an aromatic core. The effect of the functionality of the monomers on the curing process was analyzed, indicating that the reactivity during the thermally induced ring‐opening increases with the number of furan and oxazine rings in the monomers. The resulting thermosets revealed good correlation between the number of oxazine rings in the structure of the monomer and the properties of the crosslinked materials. Furfurylamine‐based polybenzoxazines showed improved thermal behavior compared to the aniline‐based systems, due to the role of furan rings. All materials showed high Tg, good thermal stability, and promising flame retardancy properties.
Compositional gradients at the nanoscale in substoichiometric thin films deposited by magnetron sputtering at oblique angles: A case study on SiOx thin films
Authors: Garcia‐Valenzuela Aurelio , Alcaide Antonio M. , Rico Victor , Ferrer Francisco J. , Alcala German , Rojas Teresa C. , Alvarez Rafael , Gonzalez‐Elipe Agustin R. , Palmero Alberto 
Published: October 2021

AbstractWe demonstrate the existence of stoichiometric variations at the nanoscale when growing nanocolumnar SiOx thin films by reactive magnetron sputtering deposition at oblique angles. Results show stoichiometric variations in the range 0.3 < x < 1.3 when growing a SiO0.5 thin film. This agrees with results from a numerical growth model that obtains a shift of the stoichiometry in all nanocolumns from lower values at the side facing the Si target to higher values at the opposite side. The different momentum distribution of the gaseous reactive and sputtered species results in preferential incorporation of the latter at a particular side of the nanocolumns. The general occurrence of this mechanism during the reactive magnetron sputtering deposition of substoichiometric thin films at oblique angles is discussed.
Dual Copper (II) Complex Supported on Diatomite as a Novel and Green Catalyst for the Synthesis of Dihydropyrano[3;2‐b]Chromenediones and Aminopyranopyrans
Authors: Davoodi Elham , Tahanpesar Elham , Massah Ahmad Reza 
Published: October 2021

AbstractImmobilized copper (II) complex, namely, 2,2′‐((1E,1′E)‐((6‐(l2‐azaneyl)‐1,3,5‐triazine‐2,4‐diyl)bis(azaneylylidene))bis(methaneylylidene))diphenol, supported on diatomite (Diatomite‐Si‐Pr‐TAT‐Bis‐(AZY‐MY)(Cu)Phenol) was introduced as a robust and heterogeneous catalyst for the synthesis of dihydropyrano[3;2‐b]chromenediones and aminopyranopyrans. The Diatomite‐Si‐Pr‐TAT‐Bis‐(AZY‐MY)(Cu)Phenol catalyst was synthesized by complexation of copper (II) acetate with TAT‐Bis‐(AZY‐MY)Phenol as a ligand with oxygen and nitrogen ligation sites that were anchored on diatomite through 3‐chloropropyltrimethoxysilane. The prepared catalyst was characterized using different microscopic and spectroscopic techniques including SEM, TEM, EDX, XRD, FT‐IR, TGA and ICP. The diatomite is available and cheap support with a high specific surface area and a large amount of hydroxyl group on the surface. A large amount of dual copper (II) complexes were supported on diatomite through covalent bonds. The Diatomite‐Si‐Pr‐TAT‐Bis‐(AZY‐MY)(Cu)Phenol showed good catalytic activity for the synthesis of dihydropyrano[3;2‐b]chromenediones and aminopyranopyrans using aromatic aldehyde, kojic acid, dimedone, or malononitrile. In addition, this catalyst system was reusable for five consecutive catalytic cycles without loss of their catalytic activity.
Headspace Gas Chromatographic Method for Carbonate Content Determination in Layered Double Hydroxides
Authors: Li Hailong , Du Chao , Liu Mengru , Zeng Jingshan 
Published: October 2021

AbstractThe determination of carbonate content is the basic procedure for studies related to layer double hydroxides (LDHs). This paper reports a rapid and accurate headspace gas chromatographic (HS‐GC) technique for the determination of carbonate content in LDHs. The content of carbonate was expressed by the amount of CO2 generated by the reaction of sulfuric acid and carbonate, which can be measured by HS‐GC technique using a thermal conductivity detector. It was found that a complete conversion of carbonate to CO2 can be achieved at 45 °C for about 4 min and a sulfuric acid dosage of 200 μL in the headspace vial. Under optimized conditions, the limit of detection and relative standard deviation of HS‐GC method is 0.79 μmol and 1 %, respectively.
Dendritic Silica Nanospheres Loaded with Red‐Emissive Enhanced Carbon Dots for Zika Virus Immunoassay
Authors: Xu Lai‐Di , Wang Si‐Wen , Zhu Jin , Zhou Tingting , Ding Shou‐Nian 
Published: October 2021

AbstractEnhanced red emissive carbon dots (CDs) and their enrichment in spheres are ideal for sensing applications. Here, we propose a novel strategy for enhancing the red emission of CDs and enriching it in dendritic SiO2 nanospheres. The surface carboxylated and red emissive CDs obtained by alkali/acid treatment of blue emissive CDs are dissolved in N‐β‐(aminoethyl)‐γ‐aminopropyltrimethoxysilane for silanization. Electron injection and long chain passivation greatly enhance the red emission of CDs. Through the reaction of silane with the hydroxyl groups of dendritic SiO2 spheres, the silanized CDs can be enriched in dendritic SiO2 spheres. Encapsulation of composite spheres with (3‐Aminopropyl)‐trimethoxysilane protects CDs and facilitates bioconjugation. These fluorescence SiO2 spheres exhibit high quantum yields in red emission (48.5 % for aqueous solution and 35.7 % for solid state) and maintain good monodispersity. It is further used as a signal of lateral flow test strips to target Zika virus, and demonstrates an ultra‐sensitive, specific and effective immunoassay. And considerable results have been achieved in the analysis of actual samples.
Hemilabile Properties of Sulfur‐Containing Cymantrene Derivatives
Authors: Kelbysheva Elena S. , Ezernitskaya Mariam G. , Strelkova Tatyana V. , Borisov Yurii A. , Telegina Lyudmila N. 
Published: October 2021

AbstractSulfur‐containing cymantrene derivatives having one or two organometallic moieties were studied by NMR, IR, UV/Vis spectroscopic methods and CVA under irradiation conditions. Photolysis of compounds 1–3 leads to the formation of rare 4‐membered chelates 4, 5 and 8. In the presence of external ligand (L), dissociation of the Mn−S bond occurred to form new dicarbonyl complexes with the Mn−L bond, which demonstrates the hemilabile character of the chelates obtained. The results were confirmed by DFT calculations. CVA method showed manganese oxidation potential value increased in the case of dicarbonyls (1313 mV for 4) as compared to that of tricarbonyls (1067 mV for 1).
Colloidal Crystal Thin Films with Square Lattice Nanoprotrusions Formed by Self‐Assembly via Spin‐Coating and Heating
Authors: Kuno Goshi , Sakaguchi Kota , Matsumoto Akikazu 
Published: October 2021

AbstractColloidal crystals with non‐close‐packed structures, such as body‐centered cubic (bcc) structures, are of high interest. Nanosized protrusions, prepared from colloidal crystals, are interesting for biomimetic applications. Herein, self‐assembly approaches for synthesizing colloidal crystals with square lattice nanoprotrusions are presented. In the first approach, spin‐coating and subsequent heating of colloidal silica and acrylic monomer results in a bcc‐like arrangement; the number of stacked colloid layers and the colloid density of these compounds are important in the formation of this structure. Moreover, prolonged heating exposes colloids from acrylic monomer, with square lattice nanoprotrusions formed. In the second approach, the protrusions are fabricated in a shorter time by replacing some of the acrylic monomer with volatile media. Only certain volatile media, such as a solvent with a structure similar to diethylene glycol, exhibit the formation of square lattice protrusions. These bottom‐up approaches contribute toward high‐throughput techniques for fabricating metastable square lattice colloidal arrangements.
Photocatalytic Properties and Electronic Effects of Incorporation Bis(acetylacetonato) Ruthenium(II/III) Complexes with Bidentate Nitrogen and Sulfur Ancillaries
Authors: Chen Chong , Tang Li H. , Zhou Wen Y. , Jia Ai Q. , Zhang Qian F. 
Published: October 2021

AbstractTreatment of cis‐[Ru(acac)2(CH3CN)2] (acac−=acetylacetonate) with 1.5 equiv. of corresponding bidentate nitrogen and sulfur ligands in ethanol gave a series of bis(acetylacetonato) ruthenium(II/III) complexes [(acac)2Ru(dimbpy)](PF6) (dimbpy=4,4′‐dimethyl‐2,2′‐bipyridine) (1), [(acac)2Ru(phen)] (phen=o‐phenanthroline) (2), [(acac)2Ru(opd)] (opd=o‐phenylenediamine) (3), [(acac)2Ru(4‐Bropd)] (4‐Bropd=4‐bromo‐o‐phenylenediamine) (4) and [(acac)2Ru(S2CNMe2)] (5), respectively. Complexes 1–5 were characterized by FT‐IR, NMR and UV‐Vis spectroscopies along with their electrochemical properties. The structures of complexes 1–5 have been unambiguously established by single crystal X‐ray crystallography. The photocatalytic properties for hydrogen production by water splitting of complexes 1–5 under visible light (λ>420 nm) were also investigated in the paper.
Regio‐ and Chemoselectivity of Oxidative Conversion of Diarylamines to N,N’‐Diaryldihydrophenazines and N,N’‐Diarylbenzidines: DFT and Experimental Study
Authors: Dulov Dmitry , Rumyantseva Anna , Levitskiy Oleg , Nefedov Sergey , Magdesieva Tatiana 
Published: October 2021

AbstractDetailed quantum‐chemical investigation of competing routes of substituted diphenylamines oxidation was performed. Chemoselectivity as well regioselectivity of the phenazine and benzidine skeletons formation were elucidated and confirmed by experimental testing on the model diphenylamines containing CF3, But, α‐methylcyclopropyl substituents. It was shown that the oxidation of 4,4’‐disubstituted donor‐acceptor amines leads to dihydrophenazines chemo‐ and regioselectively. For 2,4’‐disubstituted donor‐acceptor diphenylamines, the reaction rates for the competing reactions differ ca. 25 times in favor of the benzidine formation. Oxidation of 2,4’‐disubstituted diphenylamines with electron‐rich phenyl rings is much less selective; both benzidines and dihydrophenazines are formed. It was shown that the activation energy for the benzidines formation is strongly dependent on the electronic properties of the substituents in the starting amine, in contrast to the competing formation of the phenazines, which is more sensitive to sterical bulkiness of substituents.
Theoretical Studies on the Mechanism of the Formation of Cyclopentadienes and Dihydropyridazines
Authors: Hallooman Dhanashree , Rhyman Lydia , Dalkılıç Erdin , Daştan Arif , Elzagheid Mohamed I. , Domingo Luis R. , Ramasami Ponnadurai 
Published: October 2021

AbstractThe synthesis of cyclopentadiene derivatives via the domino reaction of norbornadienes with dimethyl 1,2,4,5‐tetrazine‐3,6‐dicarboxylate, followed a retro‐Diels‐Alder reaction, was reported by Dalkılıç few years ago (Tetrahedron 2015;71 : 1966). In some cases, the formation of an unexpected dihydropyridazine (DHP) was observed, and explained by a 1,3‐hydrogen shift. A density functional theory study is herein reported giving insights into the proposed mechanisms with different substituents on norbornadiene. Based on the kinetic and thermodynamic data, the retro‐Diels‐Alder reaction is confirmed to explain the formation of cyclopentadienes plus pyridazines. The intramolecular 1,3‐hydrogen shift mechanism was not sufficient to explain the exclusive formation of two DHPs. Thus, an alternative mechanism involving a stepwise tautomerisation is being reported for formation of DHPs.
Photoluminescent Carbon Nanodots Integrated Polymeric Materials in One Step from Molecular Precursors
Authors: Jalilov Almaz S. 
Published: October 2021

AbstractThe photoluminescence (PL) origin conundrum of the carbon nanodots (CNDs) is often restrained by the disconnect between the structural complexity of the CNDs in solid‐state versus the PL properties in the dispersed solution phase. Herein, the solid‐state photoluminescent polymeric materials synthesized by direct polyesterification of citric acid (CA) and glycols at 180 °C and 40 h. Characteristics of these polymeric materials were compared with the carbon nanodots (CNDs) prepared from direct pyrolysis of CA at similar conditions. The polymeric materials prepared with an excess of CA possess a higher yield of CA decomposition products such as molecular acids that are trapped in the polymer matrix, therefore, observe district structural and photophysical properties from the CNDs dispersed in solution. By comparing the structural and photophysical properties of the dispersed CNDs in dioxane, with those polymeric materials prepared by a single pot from CA and glycols, it is proposed that the intermediate molecular fluorophores can be trapped along with CNDs in the polymer matrix.
The Synthesis of Tetrasubstituted Cycloalkenes Bearing π‐Conjugated Substituents and Their Optical Properties
Authors: Čubiňák Marek , Bigeon John , Galář Pavel , Ondič Lukáš , Tobrman Tomáš 
Published: October 2021

AbstractWe report the development of a new methodology for the preparation of cyclic tetrasubstituted alkenes with π‐conjugated substituents. The synthesis of the target compounds was accomplished through the regioselective cross‐coupling reaction of diphenyl bromocyclohexenyl phosphate with organozinc reagents. The procedure succeeded in the preparation of alkenes with two pyrene moieties. The absorption and photoluminescence spectra of the prepared compounds were measured.
A Series of Primary Alkylamine Borane Adducts CxH2x+1NH2BH3: Synthesis and Properties
Authors: Turani‐I‐Belloto Kevin , Valero‐Pedraza María‐José , Chiriac Rodica , Toche François , Granier Dominique , Cot Didier , Petit Eddy , Yot Pascal G. , Alauzun Johan G. , Demirci Umit B. 
Published: October 2021

AbstractPrimary alkylamine borane adducts CxH2x+1NH2BH3 (CxAB) are unconventional molecules that may offer great opportunities in chemistry owing to their dihydrogen Hδ+⋅⋅⋅Hδ− bonds. Herein, we focus on six CxAB (x=4, 6, 8, 10, 12, 14), synthesized by Lewis acid‐base reaction between the complex (CH3)2S⋅BH3 and the primary alkylamines. At ambient temperature, C4AB and C6AB are oily liquid, and the other adducts are crystalline solids. The melting temperatures of the CxAB linearly increase as a function of ln(x) due to stronger intermolecular Van der Waals forces between the alkyl chains, and they are higher by 20–40 °C than those of the amines due to dihydrogen Hδ+⋅⋅⋅Hδ− bonds between the NH2BH3 heads. The occurrence of dihydrogen Hδ+⋅⋅⋅Hδ− bonds is further confirmed by molecular and structural analyses. This is discussed hereafter.
Magnetic quivers from brane webs with O7+-planes
Authors: Akhond Mohammad , Carta Federico 
Published: October 2021

Abstract
We consider the Higgs branch of 5d fixed points engineered using brane webs with an O7+-plane. We use the brane construction to propose a set of rules to extract the corresponding magnetic quivers. Such magnetic quivers are generically framed non-simply-laced quivers containing unitary as well as special unitary gauge nodes. We compute the Coulomb branch Hilbert series of the proposed magnetic quivers. In some specific cases, an alternative magnetic quiver can be obtained either using an ordinary brane web or a brane web with an O5-plane. In these cases, we find a match at the level of the Hilbert series.
A non-relativistic limit of M-theory and 11-dimensional membrane Newton-Cartan geometry
Authors: Blair Chris D. A. , Gallegos Domingo , Zinnato Natale 
Published: October 2021

Abstract
We consider a non-relativistic limit of the bosonic sector of eleven-dimensional supergravity, leading to a theory based on a covariant ‘membrane Newton-Cartan’ (MNC) geometry. The local tangent space is split into three ‘longitudinal’ and eight ‘transverse’ directions, related only by Galilean rather than Lorentzian symmetries. This generalises the ten-dimensional stringy Newton-Cartan (SNC) theory. In order to obtain a finite limit, the field strength of the eleven-dimensional four-form is required to obey a transverse self-duality constraint, ultimately due to the presence of the Chern-Simons term in eleven dimensions. The finite action then gives a set of equations that is invariant under longitudinal and transverse rotations, Galilean boosts and local dilatations. We supplement these equations with an extra Poisson equation, coming from the subleading action. Reduction along a longitudinal direction gives the known SNC theory with the addition of RR gauge fields, while reducing along a transverse direction yields a new non-relativistic theory associated to D2 branes. We further show that the MNC theory can be embedded in the U-duality symmetric formulation of exceptional field theory, demonstrating that it shares the same exceptional Lie algebraic symmetries as the relativistic supergravity, and providing an alternative derivation of the extra Poisson equation.
Effectiveness of phosphorus control under extreme heatwaves: implications for sediment nutrient releases and greenhouse gas emissions
Authors: Zhan Qing , Stratmann Cleo N. , van der Geest Harm G. , Veraart Annelies J. , Brenzinger Kristof , Lürling Miquel , de Senerpont Domis Lisette N. 
Published: October 2021

AbstractEutrophication has been identified as the primary cause of water quality deterioration in inland waters worldwide, often associated with algal blooms or fish kills. Eutrophication can be controlled through watershed management and in-lake measures. An extreme heatwave event, through its impact on mineralization rates and internal nutrient loading (phosphorus—P, and nitrogen—N), could counteract eutrophication control measures. We investigated how the effectiveness of a nutrient abatement technique is impacted by an extreme heatwave, and to what extent biogeochemical processes are modulated by exposure to heatwaves. To this end, we carried out a sediment-incubation experiment, testing the effectiveness of lanthanum-modified bentonite (LMB) in reducing nutrients and greenhouse gas emissions from eutrophic sediments, with and without exposure to an extreme heatwave. Our results indicate that the effectiveness of LMB may be compromised upon exposure to an extreme heatwave event. This was evidenced by an increase in concentration of 0.08 ± 0.03 mg P/L with an overlying water volume of 863 ± 21 mL, equalling an 11% increase, with effects lasting to the end of the experiment. LMB application generally showed no effect on nitrogen species, while the heatwave stimulated nitrification, resulting in ammonium loss and accumulation of dissolved oxidized nitrogen species as well as increased dissolved nitrous oxide concentrations. In addition, carbon dioxide (CO2)-equivalent was more than doubled during the heatwave relative to the reference temperature, and LMB application had no effect on mitigating them. Our sediment incubation experiment indicates that the rates of biogeochemical processes can be significantly accelerated upon heatwave exposure, resulting in a change in fluxes of nutrient and greenhouse gas between sediment and water. The current efforts in eutrophication control will face more challenges under future climate scenarios with more frequent and intense extreme events as predicted by the IPCC.