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Antibiotics wastewater is normally treated by anaerobic biological technology, while the performance is always not satisfied due to the inhibitory effects of high level antibiotics. Here, we investigated the quick start-up process for tetracycline wastewater treatment in expanded granular sludge bed (EGSB) reactor and also the influence of tetracycline content on performance and microbial community structure. The results indicated that gradual increase of tetracycline content could keep the stable operation of EGSB system, while cause slight inhibition. With tetracycline content increasing to 210 mg/L, chemical oxygen demand (COD) removal decreased from 96.7% to 73.3%, tetracycline removal slightly decreased from 84.6% to 81.6%, while biogas production decreased from 6.1 to 4.7 L/d with methane production rate of 208 to 175 mL/g COD. Long-term acclimation could eliminate the inhibition by tetracycline and its metabolic products to recover the microbial activity. Bacillus brevis, Cocci and Clostridium became the main bacteria with increase of tetracycline contents to form a compact and multi-layer structure of sludge. Tetracycline addition resulted in the increase of Spirochaete and Synergistetes, which might promote the removal of tetracycline. Tetracycline addition decreased the total contents of methanogens and caused less methane production. It provided an effective start-up method for anaerobic treatment of antibiotics wastewater.

A novel acetate-based ionic liquid immobilized metal organic frameworks catalyst, Fe-MIL-101-N(Bnme2)OAc, was synthesized using a straightforward ion exchange strategy. Initially, Fe-MIL-101-N(Bnme2)Br was prepared by condensing a quaternary ammonium salt ionic liquid (N(BzBnme2)Br) with Fe-MIL-101-NH2. Subsequently, the Br-ions were exchanged with OAc-ions from potassium acetate to produce the desired catalyst. The morphology, structure and physicochemical properties of the catalyst were comprehensively characterized by XRD, SEM, FT-IR, DRS UV−vis, TGA, BET, and EA, which confirmed both the successful preparation of the catalyst and the integrity of the MOFs framework. The heterogeneous catalyst Fe-MIL-101-N(Bnme2)OAc demonstrated high activity in catalyzing the reaction of N-aryl epoxy amines with CO2to form oxazolidinone compounds under optimal conditions (80oC, 8h, 1mL of MeCN, 1.0MPa CO2and 5mg catalyst), achieving a yield of up to 99% with almost no production of the by-product cyclic carbonate. Moreover, this catalyst displayed excellent recyclability and extensive substrate applicability, maintaining its catalytic activity for at least five consecutive uses. Substrates with various substituents also produced the corresponding oxazolidinone products in high yields.

Human telomerase RNA component hTERC comprises multiple motifs that contribute to hTERC biogenesis, holoenzyme activity, and enzyme recruitment to telomeres. hTERC contains several guanine tracts (G-tracts) at its 5′-end, but its associated proteins and potential roles in telomerase function are still poorly understood. The heterogeneous nuclear ribonucleoproteins F, H1, and H2 (hnRNP F/H) are splicing factors that preferentially bind to poly(G)-rich sequences RNA. Here, we demonstrate that hnRNP F/H associate with both hTERC and telomerase holoenzyme to regulate telomerase activity. We reveal hnRNP F/H bind to the 5′-end region of hTERC in vitro and in vivo, and identify the first three G-tracts of hTERC and qRRM1 domain of hnRNP F/H are required for their interaction. Furthermore, hnRNP F/H also directly interact with telomerase holoenzyme. Functionally, we show that hnRNP F/H plays important roles in modulating telomerase activity and telomere length. Moreover, hnRNP F/H deletion greatly impair cancer and stem cell proliferation, and induce stem cell senescence, while hnRNP F/H overexpression delay stem cell senescence. Collectively, our findings unveil a novel role of hnRNP F/H as the binding partners of hTERC and telomerase holoenzyme to regulate telomerase function.

Lattice thermal expansion (LTE) has been investigated in double perovskites LaPbMSbO6(M = Mn, Co, Ni). Ordinary LTE behavior with good thermal stability is identified for the Mn sample, whereas unusual LTE with a preferably expanded interplanar distance of (040) is revealed for Co and Ni samples. Temperature-dependent X-ray diffraction patterns (T-XRD), Raman spectra (T-Raman), and specific heat capacities (T-Cp) consistently indicate that a rare isostructural displacive phase transition (IDPT) with a second-order phase transition nature is predominant near the critical temperature. Refinements of neutron powder diffraction (NPD) and in situ T-XRD data present temperature-sensitive bond parameters which are relevant to planar oxygen O1. X-ray photoelectron spectra (XPS) further confirm the Jahn–Teller (J-T) activated Co2+(HS) or Ni3+(HS/LS) cations at the B-site sublattice. This unusual LTE behavior could be understood by the cooperative J-T effect contributed by a Pb2+ion and Co2+/Ni3+ion from A- and B-site sublattices, respectively. The importance of 6s(Pb)-2p(O)-3d(Co/Ni) extended orbital hybridization on affecting thermal expansion behavior is highlighted on the basis of temperature-induced phonon mode softening. This study presents a microscopic description of connection between anisotropic thermal expansion and a cooperative J-T effect, which inspired exploration of thermal–mechanical coupled functional materials based on LaPbMSbO6double perovskites.

Scheduling for the job shop is very important in both fields of production management and combinatorial optimization. However, it is quite difficult to achieve an optimal solution to this problem with traditional optimization methods owing to the high computational complexity (NP-hard). Genetic algorithms (GA) have been proved to be effective for a variety of situations, including scheduling and sequencing. Unfortunately, its efficiency is not satisfactory. In order to make GA more efficient and practical, the knowledge relevant to the problem to be solved is helpful. In this paper, a kind of hybrid heuristic GA is proposed for problem n/m/G/[C.sub.max], where the scheduling roles, such as shortest processing time (SPT) and MWKR, are integrated into the process of genetic evolution. In addition, the neighborhood search technique (NST) is adopted as an auxiliary procedure to improve the solution performance. The new algorithm is proved to be effective and efficient by comparing it with some popular methods, i.e. the heuristic of neighborhood search, simulated annealing (SA), and traditional GA. [C] 2001 Elsevier Science Ltd. All rights reserved. Keywords: Job shop scheduling; Genetic algorithm; Heuristics; Production management; Combinatorial optimization

Background: 2-Substituted benzothiazoles are a class of heterocyclic compounds that have a wide range of applications in agriculture, pharmaceutical and chemical industry due to their wide spectrum of biological and biophysical properties. Benzothiazole is usually prepared by the condensation of 2-aminobenzenethiols or 2,2'-disulfanediyldianilines, the cyclization of thioformanilides, or the sulfurization of 2-haloanilides. Furthermore, in the reaction of 2,2'-disulfanediyldianilines with aldehydes to prepare benzothiazole, the S-S bond cleavage is the key to the construction of C-S bond. Method: 2-Arylbenzothiazoles could be successfully synthesized from the reaction of 2,2'-disulfanediyldianilines with aldehydes by using easily available Na2S·9H2O as a catalyst under microwave irradiation in low power. Results: A novel methodology for preparing 2-arylbenzothiazoles from disulfides and aromatic aldehydes under microwave irradiation in the presence of Na2S has been reported. The reaction mechanism was determined by 1HNMR in detail. It is found for the first time that the S-S bond of the Schiff base could be cleaved by Na2S·9H2O and subsquent could cyclize to form the corresponding 2-arylbenzothiazole. Conclusion: 2-Substituted benzothiazoles were synthesized efficiently via the condensation of 2,2'- disulfanediyldianiline with aromatic aldehydes catalyzed by Na2S·9H2O under microwave irradiation. This methodology provides a green and general synthetic route to prepare benzothiazole with short reaction time, low microwave irradiation power, and high-yield.

The photolysis results of new diferrocenyl substituted cyclopentadienone(3) show that sunlight and air play an important role in the decomposition of compound 3, and two new compounds, 2-cyclopentenone(4) and α-pyrone(5), were obtained viaphotolysis of compound 3. The photolysis process was investigated by 1H NMR, and a plausible mechanism for the formation of compound 5was deduced. The cycloaddition reactions of substituted cyclopentadienones(3, 7, 9) with maleimide gave substituted imides 8, 10, 11, 12and an unprecedented diferrocenyl substituted 1H-pyrrol-3(2H)-one derivative 13, respectively. The structures of compounds 4, 5, 8, 10, 11, 12and 13were confirmed by X-ray single crystal diffraction analysis technique.

Background: Genome-wide association studies (GWASs) have identified hundreds of loci for body mass index (BMI), but functional variants in these loci are less known. The purpose of this study was to identify RNA modification-related SNPs (RNAm-SNPs) for BMI in GWAS loci. BMI-associated RNAm-SNPs were identified in a GWAS of approximately 700,000 individuals. Gene expression and circulating protein levels affected by the RNAm-SNPs were identified by QTL analyses. Mendelian randomization (MR) methods were applied to test whether the gene expression and protein levels were associated with BMI. Results: A total of 78 RNAm-SNPs associated with BMI (P< 5.0 × 10–8) were identified, including 65 m6A-, 10 m1A-, 3 m7G- and 1 A-to-I-related SNPs. Two functional loss, high confidence level m6A-SNPs, rs6713978 (P= 6.4 × 10–60) and rs13410999 (P= 8.2 × 10–59), in the intron of ADCY3were the top significant SNPs. These two RNAm-SNPs were associated with ADCY3gene expression in adipose tissues, whole blood cells, the tibial nerve, the tibial artery and lymphocytes, and the expression levels in these tissues were associated with BMI. Proteins enriched in specific KEGG pathways, such as natural killer cell-mediated cytotoxicity, the Rap1 signaling pathway and the Ras signaling pathway, were affected by the RNAm-SNPs, and circulating levels of some of these proteins (ADH1B, DOCK9, MICB, PRDM1, STOM, TMPRSS11D and TXNDC12) were associated with BMI in MR analyses. Conclusions: Our study identified RNAm-SNPs in BMI-related genomic loci and suggested that RNA modification may affect BMI by affecting the expression levels of corresponding genes and proteins.

The conjugate addition reactions of four organolithium reagents to 2,3,4,5-tetraphenylcyclopentadienone (tetracyclone) were investigated to reveal the reactivity of organolithium reagents to tetracyclone. The results show that 1,2-addition products 2,3,4,5-tetraphenyl-1-(2-thienyl)-2,4-cyclopentadien-1-ol(1), 1-n-butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadien-1-ol(2) and 1,2,3,4,5-pentaphenyl-2,4-cyclopentadien-1-ol(3) were synthesized in excellent yields while tetracyclone reacted with 2-thienyllithium, n-butyllithium and phenyllithium, respectively. Interestingly, three 1,2-, 1,4- and 1,6-addition isomers 1-tert-butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadien-1-ol(4), 4-tert-butyl-2,3,4,5-tetraphenyl-2-cyclopenten-l-one(5) and 2-tert-butyl-2,3,4,5-tetraphenyl-3-cyclopenten-l-one(6), were simultaneously obtained by the conjugate addition reaction of tert-butyllithium with larger steric hindrance to tetracyclone. Compounds 1—6were characterized by 1H and 13C NMR spectra, Fourier transform infrared(FTIR) spectra and mass spectra(MS). The crystal and molecular structures of compounds 1, 2and isomers 5, 6were determined by X-ray single crystal diffraction technique. The results imply that the steric hindrance of tert-butyllithium probably play a key role in controlling the conjugate addition reaction. The conjugate addition mechanism of organolithium reagents to tetracyclone was proposed.

17β-estradiol (E2) treatment of cells results in an upregulation of SIRT1 and a down-regulation of PPARγ. The decrease in PPARγ expression is mediated by increased degradation of PPARγ. Here we report that PPARγ is ubiquitinated by HECT E3 ubiquitin ligase NEDD4-1 and degraded, along with PPARγ, in response to E2 stimulation. The PPARγ interacts with ubiquitin ligase NEDD4-1 through a conserved PPXY-WW binding motif. The WW3 domain in NEDD4-1 is critical for binding to PPARΓ. NEDD4-1 overexpression leads to PPARγ ubiquitination and reduced expression of PPARγ. Conversely, knockdown of NEDD4-1 by specific siRNAs abolishes PPARΓ ubiquitination. These data indicate that NEDD4-1 is the E3 ubiquitin ligase responsible for PPARγ ubiquitination. Here, we show that NEDD4-1 delays cellular senescence by degrading PPARΓ expression. Taken together, our data show that E2 could upregulate SIRT1 expression via promoting the PPARΓ ubiquitination-proteasome degradation pathway to delay the process of cell senescence.

Underground coal gasification (UCG) is a highly efficient new type of coal mining technology with broad future prospects. In order to study the cavity extension formation in the early ignition stage of UCG, a block coal scale UCG simulation experiment was carried out. The results show that after the ignition, the temperature above ignition point rose fastest, and the coal combustion interface and high temperature area moved toward to the above of ignition point, while the temperature of the left and right sides of ignition point rose a little slowly. According to the results of dissected block coal, it is indicated that the extension scale in the vertical direction was significantly larger than other directions; the combustion cavity form was an irregular rectangle like a pear. The results of this experiment revealed the cavity extension process from ignition of UCG channels to the formation of cavity, which provided a foundation for the study of extension characteristics of UCG channel in the entire UCG process.

The mono dispersed redox-active latex particle with 0.90 μm in diameter was prepared by immobilizing ferrocenylmethanol acrylate on a surface of a polystyrene latex core through the emulsion copolymerization reaction. The aqueous suspensions exhibited stable voltammetric waves at 0.271/0.207 V vs Ag|AgCl. The anodic and the cathodic peak currents were diffusion-controlled, as if it were huge redox molecules with 3.8 × 107electrons.

An alkynyl-coupled diferrocenylpropane and azobenzene derivative has been synthesized. Photoinduced change of UV-absorbance and shifts of redox potential of synthesized compound were elucidated by time-dependent density function theory (TD-DFT) calculations, indicating that isomerization of trans to cis configuration occurs by UV irradiation.