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Geodynamic evolution in the late Paleozoic is significant for understanding the final amalgamation of the Central Asian Orogenic Belt (CAOB). No consensus has yet been reached regarding the late Paleozoic geodynamic evolution of the northern Great Xing'an Range (GXR) in northeastern China, the eastern CAOB. Furthermore, late Paleozoic syenogranitediabase dyke association is present in the Xiaokele area in northern GXR. It provides an important opportunity to understand the nature of magmatism and the geodynamic evolution during this period. This paper presents new zircon U-Pb ages, zircon Hf isotopic compositions, and geochemical data of whole rocks for Xiaokele syenogranite and diabase. Zircon U-Pb dating suggests that the Xiaokele syenogranite (292.5 [+ or -] 0.9 Ma) and diabase (298.3 [+ or -] 1.5 Ma) were emplaced during the early Permian. The Xiaokele syenogranites have high Si[O.sub.2] contents, low MgO contents, and enriched zircon [[epsilon].sub.Hf](t) values, suggesting that their primary magma was generated by the partial melting of the juvenile crustal material. The Xiaokele diabases have low Si[O.sub.2] contents, high MgO contents, are enriched in large-ion lithophile elements, depleted in high-field-strength elements, and exhibit enriched zircon [[epsilon].sub.Hf](t) values. They derived from a lithospheric mantle source that had previously been metasomatized by slab-derived fluids. Combined with previous research results, we believe that the continent-continent collision between the Xing'an and Songliao blocks occurred during the late early Carboniferous - early late Carboniferous (330-310 Ma), and the two blocks were transformed into a post-collisional extensional setting during the latest Carboniferous - early Permian. Key words: early Permian, syenogranite, diabase, post-collisional extensional setting, Xiaokele, northern Great Xing'an Range. L'evolution geodynamique au Paleozoique tardif est importante pour la comprehension de l'amalgamation finale de la ceinture orogenique d'Asie centrale (COAC). Aucun consensus n'a encore ete etabli quant a l'evolution geodynamique au Paleozoique tardif du Grand Xing'an (GX) septentrional de l'est de la COAC dans le nord-est de la Chine. En outre, une association d'age paleozoique tardif de syenogranite et de dykes de diabase est presente dans la region de Xiaokele du GX septentrional, qui offre une bonne occasion de mieux comprendre la nature du magmatisme et de l'evolution geodynamique durant cette periode. L'article presente de nouveaux ages U-Pb sur zircons, des donnees sur la composition des isotopes de Hf des zircons et des donnees geochimiques sur roche totale pour le syenogranite et la diabase de Xiaokele. La datation U-Pb sur zircons indiquerait que le syenogranite (292,5 [+ or -] 0,9 Ma) et la diabase (298,3 [+ or -] 1,5 Ma) de Xiaokele ont ete mis en place durant le Permien precoce. Les syenogranites de Xiaokele ont des teneurs elevees en Si[O.sub.2] et faibles MgO et presentent des valeurs enrichies de [[epsilon].sub.Hf](t) des zircons, ce qui indiquerait que leur magma primaire est un produit de la fusion partielle de materiau crustal juvenile. Les diabases de Xiaokele ont des teneurs en Si[O.sub.2] faibles et en MgO elevees et sont enrichies en elements lithophiles a grand rayon ionique, appauvries en elements a forte liaison atomique et presentent des valeurs enrichies de [[epsilon].sub.Hf](t) des zircons. Elles proviennent d'une source dans le manteau lithospherique ayant prealablement subi un metasomatisme cause par des fluides issus d'une plaque subductee. A la lumiere de ces resultats et de resultats de travaux anterieurs, nous croyons que la collision continent-continent des blocs de Xing'an et de Songliao s'est produite durant l'intervalle du Carbonifere precoce tardif au Carbonifere tardif precoce (330 Ma-310 Ma) et que les deux blocs se sont transformes en un milieu d'extension post-collision durant l'intervalle de la fin du Carbonifere au Permien precoce. [Traduit par la Redaction] Mots-cles: Permien precoce, syenogranite, diabase, milieu d'extension post-collision, Xiaokele, Grand Xing'an septentrional., Introduction The tectonic evolution of orogenic belts is characterized by changes in the associated magmatic composition (Harris et al. 1986). Post-collisional magmatism, as one of the common characteristics of many [...]

An efficient method for the synthesis of 2-substituted benzo[f]isoindole-4,9-dione derivatives from N-substituted iminodiacetates and quinones via a Cu(II)-promoted oxidation/[3 + 2] cycloaddition/aromatization tandem reaction was reported. This tandem reaction uses a wide range of N-substituted iminodiacetate derivatives that contain the chain-alkyl, cycloalkyl, and aryl group on the N-atom. Based on optimized reaction conditions, the desired product of 2-substituted benzo[f]isoindole-4,9-diones was obtained in moderate to excellent yields. Taken together, the promising results of this research would provide an especially efficient strategy to synthesize polysubstituted pyrroles from easy available starting materials and promoted by cheaper [Cu(OAc).sub.2]. Key words: tandem reaction, Cu(II)-promoted, 2-substituted benzo[f]isoindole-4,9-dione, oxidation/[3 + 2] cycloaddition/aromatization. Nous présentons une méthode efficace pour la synthèse des dérivés de benzo[f]isoindole-4,9-dione susbstitués en position 2 à partir d'iminodiacétates N-substitués et de quinones. La méthode proposée fait appel à une réaction en tandem qui consiste en une oxydation catalysée par le Cu(II) suivie d'une cycloaddition [3 + 2] et d'une aromatisation. Cette réaction en tandem admet une grande variété de dérivés d'iminodiacétate N-substitués comportant une chaîne alkyle ou un groupe cycloalkyle ou aryle sur l'atome d'azote. En conditions réactionnelles optimisées, nous avons obtenu le produit désiré, soit les benzo[f]isoindole-4,9-diones substituées en position 2, en rendements modérés à excellents. Pris dans leur ensemble, les résultats prometteurs de ces travaux pourraient constituer une stratégie particulièrement efficace pour synthétiser des pyrroles polysubstitués à partir de produits de départ facilement accessibles et de [Cu(OAc).sub.2], un catalyseur peu coûteux. [Traduit par la Rédaction] Mots-clés : réaction en tandem, catalyse par le Cu(II), benzo[f]isoindole-4,9-dione substitué en position 2, oxidation--cycloaddition [3 + 2]--aromatization., Introduction First-row transition metals have been widely used in the construction of organic molecules and have greatly enriched synthetic chemistry in recent years. (1-5) In particular, due to their lower [...]

Background: Linezolid is classed as oxazolidinone antibiotics which can be used to treat severe infections caused by vancomycin-resistant Enterococcus faecium, hospital-acquired pneumonia caused by Staphylococcus aureus, complicated skin, and uncomplicated skin structure infections (SSSIs) caused by methicillin-susceptible S. aureus or Streptococcus pyogenes, and community-acquired pneumonia caused by Streptococcus pneumoniae. However, many studies have suggested it can also cause thrombocytopenia and pancytopenia. Patients and Methods: We report on three patients with linezolid-pancytopenia. Patients in cases 1 and 2 were diagnosed with heart failure with preserved ejection fraction (HFpEF) and were both administered with dapagliflozin, one of the sodium-dependent glucose transporters 2 inhibitors (SHLT-2i). Results: Two patients were diagnosed with type 2 diabetes, pneumonia, and hyponatremia. Severe myelosuppression occurred in both patients, with a severe decrease in leukocytes and platelets and a moderate decrease in hemoglobin, who eventually passed away despite the discontinuation of linezolid and adopting appropriate treatment measures. The patient in case 3 was diagnosed with pneumonia, type 2 diabetes, and sequelae of cerebral thrombosis. After twelve days of treatment, the patient developed moderate thrombocytopenia and anemia. She recovered without any additional treatment after the discontinuation of linezolid. Conclusion: In this case series, two patients with irreversible myelosuppression were treated with both linezolid and SGLT-2i, and one diabetic patient with single linezolid use presented with reversible pancytopenia, suggesting that SGLT-2i may exacerbate myelosuppression of linezolid. Linezolid should be used with caution in infectious patients with a history of SGLT-2i. We will conduct relevant animal experiments to clarify the interaction between the two drugs. [ABSTRACT FROM AUTHOR]

A novel one-pot 1,3-dipolar cycloaddition/oxidation reaction of 1,4-quinones, aromatic aldehydes, and N -substituted amino esters to construct polysubstituted benzo[ f ]isoindole-4,9-diones induced by benzoic acid is reported. Based on optimized reaction conditions, various polysubstituted benzo[ f ]isoindole-4,9-diones derivatives are obtained in moderate yields. This straightforward methodology employs mild reaction conditions, a green oxidant, and readily available starting materials. Notably, a wide range of substrates is tolerated. [ABSTRACT FROM AUTHOR]

A simple and highly efficient method for the preparation of tetrasubstituted NH -pyrrole from a wide range of chalcones and diethyl iminodiacetates via a Cu(OAc)2-promoted oxidation/[3+2]cycloaddition/aromatization cascade reaction has been developed. This reaction proceeds through dehydrogenations, deamination, and oxidative cyclization, affording the corresponding products in good to excellent yields. This convenient methodology for constructing tetrasubstituted NH -pyrroles has several advantages over existing methods, such as the use of easily accessible chalcones and readily available diethyl iminodiacetates, and mild reaction conditions. A wide range of substrates are tolerated. [ABSTRACT FROM AUTHOR]

Background/Aims: Parkinson's disease (PD) is a frequently occurring condition that resulted from the loss of midbrain neurons, which synthesize the neurotransmitter dopamine. In this study, we established mouse models of PD to investigate the expression of microRNA-128 (miR-128) and mechanism through which it affects apoptosis of dopamine (DA) neurons and the expression of excitatory amino acid transporter 4 (EAAT4) via binding to axis inhibition protein 1 (AXIN1). Methods: Gene expression microarray analysis was performed to screen differentially expressed miRNAs that are associated with PD. The targeting relationship between miR-128 and AXIN1 was verified via a bioinformatics prediction and dual-luciferase reporter gene assay. After separation, DA neurons were subjected to a series of inhibitors, activators and shRNAs to validate the mechanisms of miR-128 in controlling of AXIN1 in PD. Positive protein expression of AXIN1 and EAAT4 in DA neurons was determined using immunocytochemistry. miR-128 expression and the mRNA and protein levels of AXIN1 and EAAT4 were evaluated via RT-qPCR and Western blot analysis, respectively. DA neuron apoptosis was evaluated using TUNEL staining. Results: We identified AXIN1 as an upregulated gene in PD based on the microarray data of GSE7621. AXIN1 was targeted and negatively mediated by miR-128. In the DA neurons, upregulated miR-128 expression or sh-AXIN1 increased the positive expression rate of EAAT4 together with mRNA and protein levels, but decreased the mRNA and protein levels of AXIN1, apoptosis rate along with the positive expression rate of AXIN1; however, the opposite trend was found in response to transfection with miR-128 inhibitors. Conclusion: Evidence from experimental models revealed that miR-128 might reduce apoptosis of DA neurons while increasing the expression of EAAT4 which might be related to the downregulation of AXIN1. Thus, miR-128 may serve as a potential target for the treatment of PD. [ABSTRACT FROM AUTHOR]

High-photostability fluorescent (XZn)Fe 2 O 4 (X = Mg, Mn or Ni) embedded in BiFeO 3 spinel-perovskite nanocomposites were successfully fabricated via a novel bio-induced phase transfer method using shewanella oneidensis MR-1. These nanocomposites have the near-infrared fluorescence response (XZn or Fe)-O-O-(Bi) interfaces (785/832 nm), and the (XZn)Fe 2 O 4 /BiFeO 3 lattices with high/low potentials (572.15–808.77 meV/206.43–548.1 meV). Our results suggest that heavy metal ion (Cr 3+ , Cd 2+ , Co 2+ and Pb 2+ ) d↓ orbitals hybridize with the paired-spin X-Zn-Fe d↓-d↓-d↑↓ orbitals to decrease the average polarization angles (−29.78 to 44.71°), qualitatively enhancing the photovoltage response selective potentials (39.57–487.84 meV). The fluorescent kinetic analysis shows that both first-order and second-order equilibrium adsorption isotherms are in line and meet the Langmuir and Freundlich modes. Highly selective fluorescence detection of Co 2+ , Cr 3+ and Cd 2+ can be achieved using Fe 3 O 4 -BiFeO 3 (Langmuir mode), (MgZn)Fe 2 O 4 -BiFeO 3 and (MnZn)Fe 2 O 4 -BiFeO 3 (Freundlich mode), respectively. Where the corresponding max adsorption capacities (q max ) are 1.5–1.94, 35.65 and 43.7 multiple, respectively, being more competitive than that of other heavy metal ions. The present bio-synthesized method might be relevant for high-photostability fluorescent spinel-perovskite nanocomposites, for design of heavy metal ion sensors. [ABSTRACT FROM AUTHOR]

In this study, a superoxide dismutase gene (PsSOD) from Pseudoalteromonas sp. ANT506 was cloned and over expressed in Escherichia coli. The PsSOD has an open reading frame of 582 bp with a putative product of 193 amino acid residue and an estimated molecular size of 21.4 kDa. Histagged PsSOD was subsequently purified 12.6-fold by Ni-affinity chromatography and the yield of 22.9%. The characterization of the purified rPsSOD exhibited maximum activity at 30 °C and pH 8.0. The enzyme exhibited 13.9% activity at 0 °C and had high-thermo lability at higher than 50 °C. rPsSOD exhibited well capability to 2.5M NaCl (62.4%). These results indicated that rPsSOD exhibited special catalytic properties. [ABSTRACT FROM AUTHOR]

An unexpected strategy has been discovered for the construction of polysubstituted aromatic core derivatives from the reaction of quinones or N-substituted maleimides with β-enamino esters by a cycloaddition/oxidative aromatization sequence that provides products contrary to those delivered by the Nenitzescu reaction. The current method provides a highly favorable synthetic strategy for the efficient construction of important therapeutic agents containing polysubstituted aromatic core structures. [ABSTRACT FROM AUTHOR]

Abstract: An efficient strategy for one-pot synthesis of a variety of naphthoquinon-1,3-dithiole derivatives has been developed. The combined action of the formal cycloaddition and oxidation reaction of quinones and amines in the presence of CS2 without additional oxidant produced naphthoquinon-1,3-dithiole derivatives in good yields. [Copyright &y& Elsevier]

Novel 2-iodo-3-(alkylamino) naphthalene-1,4-diones are formed in 33-70% yield by the reaction of alkylamine and 1, 4-naphthoquinone in the presence of iodine. [ABSTRACT FROM AUTHOR]

Solvent‐free reactions of C60 and C70 with diethyl bromomalonate in the presence of various inorganic bases were investigated under the high‐speed vibration milling (HSVM) conditions, and are shown to give methanofullerenes 1 and 2 in good to excellent yields based on consumed fullerenes. Several weak inorganic bases were found to be quite effective in promoting the solvent‐free mechanochemical Bingel reactions of C60 and C70 under the HSVM conditions. Among the studied bases, sodium acetate gave the highest yield of monoadducts, while potassium carbonate afforded a considerable amount of bisadducts for both C60 and C70. #Visiting Scholar from College of Material Sciences, Southwest University of Science and Technology. [ABSTRACT FROM AUTHOR]

In microelectronic packaging technology for three-dimensional integrated circuits (3D ICs), Cu-to-Cu direct bonding appears to be the solution to solve the problems of Joule heating and electromigration (EM) in solder microbumps under 10 μ m in diameter. However, EM will occur in Cu–Cu bumps when the current density is over 10 6   A / cm 2 . The surface, grain boundary, and the interface between the Cu and TiW adhesion layer are the three major diffusion paths in EM tests, and which one may lead to early failure is of interest. This study showed that bonding strength affects the outcome. First, if the bonding strength is not strong enough to sustain the thermal mismatch of materials during EM tests, the bonding interface will fracture and lead to an open circuit of early failure. Second, if the bonding strength can sustain the bonding structure, voids will form at the passivation contact area between the Cu–Cu bump and redistribution layer (RDL) due to current crowding. When the void grows along the passivation interface and separates the Cu–Cu bump and RDL, an open circuit can occur, especially when the current density and temperature are severe. Third, under excellent bonding, when the voids at the contact area between the Cu–Cu bump and RDL do not merge together, the EM lifetime can be more than 5000 h. [ABSTRACT FROM AUTHOR]

The failure mechanisms of Cu–Cu bumps under thermal cycling test (TCT) were investigated. The resistance change of Cu–Cu bumps in chip corners was less than 20% after 1000 thermal cycles. Many cracks were found at the center of the bonding interface, assumed to be a result of weak grain boundaries. Finite element analysis (FEA) was performed to simulate the stress distribution under thermal cycling. The results show that the maximum stress was located close to the Cu redistribution lines (RDLs). With the TiW adhesion layer between the Cu–Cu bumps and RDLs, the bonding strength was strong enough to sustain the thermal stress. Additionally, the middle of the Cu–Cu bumps was subjected to tension. Some triple junctions with zig-zag grain boundaries after TCT were observed. From the pre-existing tiny voids at the bonding interface, cracks might initiate and propagate along the weak bonding interface. In order to avoid such failures, a postannealing bonding process was adopted to completely eliminate the bonding interface of Cu–Cu bumps. This study delivers a deep understanding of the thermal cycling reliability of Cu–Cu hybrid joints. [ABSTRACT FROM AUTHOR]