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The reaction of Bppy(Mes)2 (BN1; ppy = 2-phenylpyridine) and BCH2ppy(Mes)2 (BN3) with the reducing reagent resulted in the 4,4′bipyridyl liganded neutral, anionic, and dianionic compounds.

The element nitrogen and nitrogenous compounds are vital to life. The synthesis of nitrogen-containing compounds using dinitrogen as the nitrogen source, not through ammonia, is of great interest and great value but remains a grand challenge. Herein, we describe a strategy to realize this transformation by combining the heterogeneous approach with the homogeneous methodology. The N2 molecule was first fixed with carbon and LiH through a one-pot heterogeneous process, forming Li2CN2 as an ‘activated’ nitrogen source with high efficiency. Then subsequent homogeneous treatments of Li2CN2 to construct the organic synthon carbodiimide and the RNA/DNA building block pyrimidines were fulfilled. By using 15N2 as the feedstock, their corresponding 15N-labeled carbodiimide and pyrimidines were readily obtained. This homogeneous–heterogeneous synergy strategy will open a new chapter for N2 transformation.

The catalytic regioselective C–H silylation of a wide range of alkoxy-substituted benzene derivatives with primary hydrosilane was achieved by the use of scorpionate-supported calcium benzyl comple...

The first examples of scandium methylidyne complexes [(Cp*)Sc(μ2-X)]3(μ3-CH) (Cp* = C5Me5; X = Br, Me, OMe), free of Lewis acids, can be achieved in high yields from [(Cp*)ScMe2]2 through a facile route. The chemical and geometrical flexibility to incorporate organic substrates indicates a rich chemistry of complex [(Cp*)Sc(μ2-OMe)]3(μ3-CH).

Hydrogenolysis of the scorpionate-supported calcium benzyl complex [(TpAd,iPr)Ca(p-CH2C6H4-Me)(THP)] (TpAd,iPr = hydrotris(3-adamantyl-5-isopropyl-pyrazolyl)borate, THP = tetrahydropyran) (2-THP) afforded the mononuclear calcium hydrido complex [(TpAd,iPr)Ca(H)(THP)] (3). Under mild conditions (40 °C, 10 atm H2, 5 mol% cat.), complex 3 effectively catalyzed the hydrogenation of a variety of alkenes, including activated alkenes, semi-activated alkenes, non-activated terminal and internal alkenes. Mononuclear calcium unsubstituted alkyl complex [(TpAd,iPr)Ca{(CH2)4Ph}(THP)] (6), proposed as the catalytic hydrogenation intermediate, was isolated and structurally characterized.

Treatment of a divalent ytterbium hydride complex [(Tp

International audience; Treatment of a divalent ytterbium hydride complex [(Tp(Ad,iPr))-Yb(H)(THF)] (Tp(Ad,iPr) = hydrotris(3-adamantyl-5-isopropyl-pyrazolyl)borate) (1) with CO, CO2 and CS2 resulted in the formation of a divalent ytterbium ethenediolate complex [(Tp(Ad,iPr))Yb](2)(cis-OCH=CHO) (2), a formate complex [(Tp(Ad,iPr))Yb(kappa(2)-O2CH)(THF)] (3), and a trivalent ytterbium ethenetetrathiolate complex [(Tp(Ad,iPr))-Yb-III](2)(C2S4) (4), respectively. DFT calculations were carried out to elucidate the reaction profiles of complexes 3 and 4.

To analyse the cytopathological features of fine needle aspiration (FNA) in angioimmunoblastic T-cell lymphoma (AITL) diagnostics.Fine needle aspiration lymph node biopsy samples from 12 patients with AITL were collected at a single centre between January 2014 and December 2020. The clinical, cytological and histopathological characteristics were retrospectively analysed.Three male and six female patients with AITL who had a median onset age of 65 years (range 51-74 years) and a mean follow-up period of 29 months (range 12-47 months) were included. The FNA cytological and morphological analysis of the reactive lymph node background revealed diffusely distributed non-homogeneous mixed lymphocytes, including mature small lymphocytes, medium-sized lymphoid cells, immune cells, and plasma cells; some mixed eosinophils, macrophages, and an occasional mixture of visible and medium-sized lymphocytes and epithelioid cells were observed. Mitotically active lymphocytes and sporadic pigmented bodies were observed occasionally. An abnormal proliferation of follicular dendritic cells observed under the microscope is important for AITL diagnosis, and these cells are often distributed in a scattered pattern of small clusters with many nuclear morphologies. Branched capillaries are another important diagnostic clue. Two patients with AITL who achieved clinical remission after treatment experienced recurrence and were diagnosed using FNA and cell block immunohistochemistry.Fine needle aspiration provides clues for the diagnosis of AITL in special clinical situations, and cell block immunohistochemistry is worthy of further exploration.

International audience; The first mononuclear divalent ytterbium hydride complex [(Tp(Ad,iPr))Yb(H)(THF)] (Tp(Ad,iPr) = hydrotris(3-adamantyl-5-isopropyl-pyrazolyl)borate) (2) bearing a terminal hydrido ligand was obtained by hydrogenolysis of the benzyl precursor in hexane. Complex 2 exhibited two different reaction patterns towards allenes: Yb-H addition with cyclohexylallene and deprotonation of 1,1-dimethylallene.

International audience; Hydrogenolysis of the half-sandwich penta-arylcycopentadienyl-supported rare-earth metal dibenzyl complexes [(Cp-Ar5)Ln(p-CH2-C6H4-Me)(2)(THF)] (Cp-Ar5 = C5Ar5, Ar = 3,5-Pr-i(2)-C6H3; Ln = Sc, La) afforded a bimetallic scandium complex [(Cp-Ar5)Sc(H)(mu-OC4H9)](2) (2) with two terminal hydrido ligands, and a double-sandwich bimetallic lanthanum hydride complex [(Cp-Ar5)La(mu-H)](2) (4) bearing the reduced Cp-Ar5 ligand. DFT calculations were conducted to elucidate the reaction profiles.

Hydrogenolysis of the half-sandwich penta-arylcyclopentadienyl-supported heavy alkaline-earth-metal alkyl complexes (CpAr )Ae[CH(SiMe3 )2 ](S) (CpAr =C5 Ar5 , Ar=3,5-i Pr2 -C6 H3; S=THF or DABCO) in hexane afforded the calcium, strontium, and barium metal-hydride complexes as the same dimers [(CpAr )Ae(μ-H)(S)]2 (Ae=Ca, S=THF, 2-Ca; Ae=Sr, Ba, S=DABCO, 4-Ae), which were characterized by NMR spectroscopy and single-crystal X-ray analysis. 2-Ca, 4-Sr, and 4-Ba catalyzed alkene hydrogenation under mild conditions (30 °C, 6 atm, 5 mol % cat.), with the activity increasing with the metal size. A variety of activated alkenes including tri- and tetra-substituted olefins, semi-activated alkene (Me3 SiCH=CH2 ), and unactivated terminal alkene (1-hexene) were evaluated.

A heteroleptic barium aminobenzyl complex [(TpAd,iPr)Ba(o-CH2C6H4-NMe2)] (1) was obtained in excellent yield from a simple one-pot reaction. Treatment of [(TpAd,iPr)Ba(o-CH2C6H4-NMe2)] (1) with two equivalents of AlR3 (R = Me, Et) led to the formation of barium tetraalkylaluminate complexes [(TpAd,iPr)Ba(AlR4)]n (R = Me, n = 2, 2; R = Et, n = 1, 3) as dimers or monomers in the solid state. The TpAd,iPr ligand-free peralkylated barium complex [Ba(AlEt4)2]n was isolated by the addition of ten equivalents of AlEt3 under the same conditions. The donor-induced aluminate cleavage is not applicable when donor solvents are added to complexes 2 and 3. In the solution of complexes 2 and 3, the alkylaluminate moieties and TpAd,iPr ligands show a rapid fluxional behavior in [D8]toluene solution over the temperature range of -70 to 25 °C, without any significant decoalescence of the corresponding proton signals.

International audience; The monomeric actinide dihydrido complex [(Cp-Ar*)(Cp*)ThH2(THF)] (2) bearing the super-bulky penta-arylcyclopentadienyl (Cp-Ar* = C5Ar*(5), Ar* = 3,5-Bu-t(2)-C6H3) and pentamethylcyclopentadienyl (Cp* = C5Me5) ligands was obtained for the first time. Complex 2 underwent unique Th-H addition reactions with various unsaturated compounds to afford the corresponding five-membered metallacycles, including the first example of actinide metallacyclopentyne [(Cp-Ar*)(Cp*)Th(PhCH-CC-CHPh)] (4).

Under mild conditions (25 °C, 5 mol% cat.), highly selective homo- and cross-desilacoupling of aryl and benzyl primary silanes to secondary silanes was achieved by the use of the heteroleptic barium aminobenzyl complex [(TpAd,iPr)Ba(CH2C6H4NMe2-o)] (TpAd,iPr = hydrotris(3-adamantyl-5-isopropyl-pyrazolyl)borate) (1) as a catalyst. Dihydrosilanes originating from catalytic redistribution and cross-desilacoupling reactions were isolated in fine yields, which demonstrates the feasible application of the barium complex in the syntheses of secondary aryl- and benzylsilanes.

We investigated the terpolymerization of ethylene/propylene/ω-Cl-α-vinyl monomers to obtain polar terpolymers by non-metallocene catalyst Cat.L-Pd through coordination polymerization directly. The functional ω-Cl-α-vinyl monomer inserted into the polymeric molecules changed the properties of the obtained polymers. The optimum catalyst Cat.L-Pd and polymerization conditions were optimized for the terpolymerization. The structure and properties of the terpolymers were characterized by FTIR, 13C (1H) NMR, DSC and GPC. The optimum incorporation content of 11-chloro-1-undecylene within the terpolymer chains is up to 3.58 mol%. The polar monomers did not carry out the homopolymerization itself, but efficiently joined the terpolymerization with ethylene and propylene. Propylene monomer was in favor of the copolymerization with ethylene beside its homopolymerization. But polypropylene segments were not observed within the terpolymer chains. Compared to the polar monomers and propylene, ethylene was the most efficient monomer for joining the terpolymerization of ethylene/propylene/ω-Cl-α-vinyl monomers, and longer segments of polyethylene were produced within the terpolymer chains. M w up to 2×105 g/mol of the terpolymers was obtained by the catalyst system. The terpolymer molecular weight distribution (MWD) was about 2 to 3, implying the terpolymerization behavior followed the single-site mechanism.

Hydrogenolysis of the scorpionate-supported barium alkyl complex (Tp^Ad,iPr)Ba[CH(SiMe3)2](THF) (Tp^Ad,iPr = hydrotris(3-adamantyl-5-isopropyl-pyrazolyl)borate) afforded the dinuclear barium hydrido complex [(Tp^Ad,iPr)Ba(µ-H)]2 (2), which was characterized by NMR spectroscopy and single crystal X-ray analysis. Exposure of 2 with 1 atm of CO resulted in a reductive coupling process to form the cis-ethendiolate dianion (3). Reaction of 2 with one equivalent of PhCC-CCPh gave barium 1,4-diphenyl-2-butyne-1,4-diyl complex {[(Tp^Ad,iPr)Ba]2(PhCH-CC-CHPh) (4).

We investigate the compatibility of $$I_0$$I0 with various combinatorial principles at $$\lambda ^+$$ź+, which include the existence of $$\lambda ^+$$ź+-Aronszajn trees, square principles at $$\lambda $$ź, the existence of good scales at $$\lambda $$ź, stationary reflections for subsets of $$\lambda ^{+}$$ź+, diamond principles at $$\lambda $$ź and the singular cardinal hypothesis at $$\lambda $$ź. We also discuss whether these principles can hold in $$L(V_{\lambda +1})$$L(Vź+1).

Treatment of the barium hydride complex [(TpAd,iPr)Ba(μ-H)]2 (TpAd,iPr = hydrotris(3-adamantyl-5-isopropyl-pyrazolyl)borate) (1) with an excess amount of 1,1-diphenylethylene (DPE) afforded the corresponding mono-DPE adduct [(TpAd,iPr)Ba(η6-Ph)C(Ph)Me] (2) and di-DPE adduct [(TpAd,iPr)Ba(η6-Ph)C(Ph)-CH2-C(Ph)2Me] (3), which could convert to each other through a reversible equilibrium reaction. Complex 1 catalysed DPE hydrogenation under mild conditions (30 °C, 6 atm, 5 mol% cat.).

Background Acute meningitis and encephalitis syndromes (AMES) is a severe neurological infection which causes high case fatality and severe sequelae in children. To determine the etiology of childhood AMES in Shenzhen, a hospital-based study was undertaken. Methods A total of 240 cerebrospinal fluid (CSF) samples from 171 children meeting the case definition were included and screened for 12 common causative organisms. The clinical data and conventional testing results were collected and analyzed. Whole genome sequencing was performed on a Neisseria meningitidis isolate. Results A pathogen was found in 85 (49.7%) cases; Group B Streptococcus (GBS) was detected in 17 cases, Escherichia coli in 15, Streptococcus pneumoniae in 14, enterovirus (EV) in 13, herpes simplex virus (HSV) in 3, N. meningitidis in 1, Haemophilus influenzae in 1, and others in 23. Notably, HSV was found after 43 days of treatment. Twelve GBS and 6 E. coli meningitis were found in neonates aged less than 1 month; 13 pneumococcal meningitis in children aged > 3 months; and 12 EV infections in children aged > 1 year old. The multilocus sequence typing of serogroup B N. meningitidis isolate was ST-3200/CC4821. High resistance rate to tetracycline (75%), penicillin (75%), and trimethoprim/sulfamethoxazole (75%) was found in 4 of S. pneumoniae isolates; clindamycin (100%) and tetracycline (100%) in 9 of GBS; and ampicillin (75%) and trimethoprim/sulfamethoxazole (67%) in 12 of E. coli. Conclusions The prevalence of N. meningitidis and JEV was very low and the cases of childhood AMES were mainly caused by other pathogens. GBS and E. coli were the main causative organisms in neonates, while S. pneumoniae and EV were mainly found in older children. HSV could be persistently found in the CSF samples despite of the treatment. A better prevention strategy for GBS, the introduction of pneumococcal vaccine, and incorporation of PCR methods were recommended.

Non-metallocene catalysts containing [N, Si, N, P]-type ligands based on diphenyl phosphorus-phenylamine and their derivatives were synthesized and characterized by H(13C) NMR, ESI–MS and micro analysis. They were able to catalyze copolymerization of ethylene with N-acetyl-O-(hex-5-enyl)-l-tyrosine ethyl ester after activated by methylaluminoxane (MAO). Effects of transition metal atoms (Ti, Zr and Hf), ligand structures and polymerization conditions were investigated. The structures and properties of the obtained polymers were characterized by FT-IR, 13C NMR, GPC and DSC. The results indicated that the obtained copolymers had high weight average molecular weight of 2.70 × 105 g/mol and high comonomer incorporation rate of 23.07 wt% within the copolymer chain. The melting temperature of the copolymer was up to 138.6 °C higher than that of the polyethylene.

A series of titanium and zirconium complexes with ligands based on di-isopropyl phosphorus-phenylamine and their derivatives were synthesized and characterized. These catalysts were utilized to catalyze the copolymerization of ethylene with N-acetyl-O-(dec-9-enyl)-L-tyrosine ethyl ester with high catalytic activity of 6.63 × 104 g P (mol Ti)−1 h−1 after activation by methylaluminoxane (MAO). The effects of ligand structure, metal atoms (Ti, Zr) and polymerization conditions were investigated in detail. The obtained polymers were characterized by 13C-NMR, DSC, FT-IR, and GPC. The results showed that the obtained copolymer had a high comonomer incorporation rate of 2.56 mol % within the copolymer chain. The melting temperature of the copolymer was up to 138.9 °C, higher than that of the obtained homopolyethylene.

In this paper, we analyze structures of Zermelo degrees via a list of four degree theoretic questions (see §2) in various fine structure extender models, or under large cardinal assumptions. In particular we give a detailed analysis of the structures of Zermelo degrees in the Mitchell model for ω many measurable cardinals. It turns out that there is a profound correlation between the complexity of the degree structures at countable cofinality singular cardinals and the large cardinal strength of the relevant cardinals. The analysis applies to general degree notions, Zermelo degree is merely the author’s choice for illustrating the idea.I0(λ) is the assertion that there is an elementary embedding j : L(Vλ+1) → L(Vλ+1) with critical point < λ. We show that under I0(λ), the structure of Zermelo degrees at λ is very complicated: it has incomparable degrees, is not dense, satisfies Posner–Robinson theorem etc. In addition, we show that I0 together with a mild condition on the critical point of the embedding implies that the degree determinacy for Zermelo degrees at λ is false in L(Vλ+1). The key tool in this paper is a generic absoluteness theorem in the theory of I0, from which we obtain an analogue of Perfect Set Theorem for “projective” subsets of Vλ+1, and the Posner–Robinson follows as a corollary. Perfect Set Theorem and Posner–Robinson provide evidences supporting the analogy between $$AD$$ over L(ℝ) and I0 over L(Vλ+1), while the failure of degree determinacy is one for disanalogy. Furthermore, we conjecture that the failure of degree determinacy for Zermelo degrees at any uncountable cardinal is a theorem of $$ZFC$$.

A series of N-acetyl-O-(ω-alkenyl)-l-tyrosine ethyl esters were synthesized by the reaction of vinyl bromides (4-bromo-1-butene, 6-bromo-1-hexene, 8-bromo-1-octene and 10-bromo-1-decene) with N-acetyl-l-tyrosine ethyl ester. 1H NMR, elemental analysis, FT-IR, and mass spectra were performed for these N-acetyl-O-(ω-alkenyl)-l-tyrosine ethyl esters. The novel titanium complex can catalyze the copolymerization of ethylene and N-acetyl-O-(ω-alkenyl)-l-tyrosine ethyl esters efficiently and the highest catalytic activity was up to 6.86 × 104 gP·(molTi)−1·h−1. The structures and properties of the obtained copolymers were characterized by FT-IR, (1H)13C NMR, GPC, DSC, and water contact angle. The results indicated that the obtained copolymers had a uniformly high average molecular weight of 2.85 × 105 g·mol−1 and a high incorporation ratio of N-acetyl-O-(but-3-enyl)-l-tyrosine ethyl ester of 2.65 mol % within the copolymer chain. The units of the comonomer were isolated within the copolymer chains. The insertion of the polar comonomer into a copolymer chain can effectively improve the hydrophilicity of a copolymer.

The purpose of this study was to compare data collected via online surveys to via paper-and-pencil ones in mental health fields. Two groups of participants completed the Adult Adaptation Inventory (AAI) and Self-rating depression scale (SDS) either in online format or in paper-and-pencil format independently. Data collected via paper-and-pencil surveys had more missing data than Internet-based ones. As for internal consistency, there were no significant differences in AAI between both two groups, while internal consistency of SDS in the online format was much higher than in the paper-and-pencil format. There was measurement invariance of both two scales across the two conditions. Finally, there were no significant differences in mean scores of both two scales between both two formats. The basic similarity of the properties across the two conditions suggests the viability of the Internet-based surveys for assessing mental health status of adults.

Online crisis decision support system (CDSS) plays an important role in the process of preventing disasters. It also provides a variety of information resources (such as data, models, knowledge, technology of maintain and repair), in addition, CDSS can also be used as an analysis tool to help individuals or groups under disasters to do prevention and mitigation with a high-level and high-quality decision-making. Moreover, building an online CDSS is important to deal with the complex and important disaster in practice. And the main purpose of this paper is to present how the online CDSS works for disaster prevention, and to deeply study decision-making theory of disasters under virtual environment. Hence, it would provide an important theoretical guidance for further study.