Search

Paddy soils are potential hotspots of combined contamination with arsenic (As) and antibiotics, which may induce co-selection of antibiotic resistance genes (ARGs) and As biotransformation genes (ABGs), resulting in dissemination of antimicrobial resistance and modification in As biogeochemical cycling. So far, little information is available for these co-selection processes and specific patterns between ABGs and ARGs in paddy soils. Here, the 16S rRNA amplicon sequencing and high-throughput quantitative PCR and network analysis were employed to investigate the dynamic response of ABGs and ARGs to As stress and manure application. The results showed that As stress increased the abundance of ARGs and mobile genetic elements (MGEs), resulting in dissemination risk of antimicrobial resistance. Manure amendment increased the abundance of ABGs, enhanced As mobilization and methylation in paddy soil, posing risk to food safety. The frequency of the co-occurrence between ABGs and ARGs, the host bacteria carrying both ARGs and ABGs were increased by As or manure treatment, and remarkably boosted in soils amended with both As and manure. Multidrug resistance genes were found to have the preference to be co-selected with ABGs, which was one of the dominant co-occurring ARGs in all treatments, and manure amendment increased the frequency of Macrolide-Lincosamide-Streptogramin B resistance (MLSB) to co-occur with ABGs. Bacillus and Clostridium of Firmicutes are the dominant host bacteria carrying both ABGs and ARGs in paddy soils. This study would extend our understanding on the co-selection between genes for antibiotics and metals, also unveil the hidden environmental effects of combined pollution.

The authors have requested that this preprint be removed from Research Square.

Soil is the material basis for human survival. However, in China, soils are wildly polluted by heavy metals, which poses serious health risks to humans. Bioremediation of heavy-metal contaminated soil is widely considered as a sustainable remediation strategy, but low remediation efficiency is still a scientific bottleneck of bioremediation. There are abundant microorganisms, plants and animals living in soils. Among these soil biota, there are complex interactions to form an intricate food web through material circulation and energy transfer. These interactions among soil biota affect the transportation and transformation of pollutants in soil, and consequently influence the bioremediation efficiency. The synergistic remediation by soil biota combines the advantages of diferent organisms to enhance the efficiency of bioremediation. In this paper, the interactions among soil biota and their influence on heavy-metal transportation and transformation, as well as bioremediation efficiency are reviewed. We also propose perspectives for future researches, including targeted regulating the structure of soil food web, improving the bioremediation efficiency of heavy-metal contaminated soil, and building a synergistic remediation technology with multi-organisms based on food web.土壤是人类赖以生存的物质基础。我国土壤重金属污染状况不容乐观，给人类健康构成严重威胁。生物修复重金属污染土壤被广泛认为是可持续的修复技术，但当前仍存在修复效率不高的科学瓶颈问题。土壤中生活着丰富的微生物、植物和动物，且这些生物之间存在着复杂的相互作用，并且通过物质循环和能量传递形成了错综复杂的食物网联系。土壤生物间的相互作用能深刻影响土壤中污染物的迁移转化和生物修复的效率，多元生物协同的修复技术集合了单一生物修复方法的优势，具有强化生物修复效果的巨大潜力。文中综述了土壤中微生物-植物-动物之间的相互作用，及其对土壤重金属迁移转化和生物修复效果的影响，并对定向调控土壤食物网结构、提高重金属污染土壤的生物修复效果、建立基于食物网的多元生物协同修复技术进行了展望。.

Ovarian cancer is the second most common gynaecological malignancy, and microRNAs (miRNAs) play important role in the cancer development. Here, we found that the level of miR-200b/200a/429 was significantly increased in serum and tumor tissues of patients with stage-I ovarian cancer. Consistent with these results, we detected increased expression levels of miR-200b/200a/429 in ovarian cancer cell lines compared with the human nontumorigenic ovarian epithelial cell line T80. The overexpression of miR-200b/200a/429 in T80 cells stimulated proliferation and caused their growth in soft agar and tumor formation in nude mice. Furthermore, we determined that miR-200b/200a/429 targets inhibitor of growth family 5 (ING5) and that the overexpression of ING5 can block miR-200b/200a/429-induced T80 cell transformation and tumorigenesis. Our findings suggest that miR-200b/200a/429 may be a useful biomarker for the early detection of ovarian cancer and that miR-200b/200a/429 significantly contributes to ovarian cancer development through ING5.

Exposure to combustion-derived nanoparticles is recognized as a major health hazard, but the molecular responses are still insufficiently described. The transcription factor erythroid 2-related factor 2 (Nrf2, also known as NFE2L2) is a master regulator of the pulmonary defense system against insults by particulate matter. However, its downstream molecular processes are not fully characterized. In the current study, BALB/c wild-type (WT) and Nrf2−/− mice were exposed by intranasal administration to fly ash particles (F3-S; 20 mg/kg BW), which were collected from a municipal waste incinerator in China, for three consecutive days. Using a comparative transcriptomics approach, the pulmonary global gene expression profiles to F3-S exposure were characterized for both genotypes. The preponderance of the differentially-expressed genes (DEGs) in WT mice induced by the fly ash particles, was related to inflammation. Functional enrichment and molecular pathway mapping of the DEGs specific to Nrf2−/− mice exposed to the particles revealed that all of the top 10 perturbed molecular pathways were associated with the inflammatory response. Our study identified a transcriptional signature related to the initial pulmonary injury in mouse upon fly ash exposure, and suggests an anti-inflammatory role of Nrf2 in protecting the lung against such exposure.

Cucumber damping-off disease mainly caused by Rhizoctonia solani leads to serious loss in agricultural production. In this study, the effective and environmentally friendly methods, using two biological agents combined with applying organic matter or reductive soil disinfestation (RSD), were performed to control the disease. Real-time PCR and MiSeq pyrosequencing were used to investigate the microbial community changes during the biocontrol process. The results showed that the applications of organic matter and antagonists (Ant) significantly decreased R. solani population and disease incidence, and increased soil microbial population and activity. However, antagonists application combined with RSD (RSD + Ant) behaved much better in nearly all aspects, and facilitated to maintain the population and activity of antagonists. Compared to the applications of organic matter and antagonists, the combination of RSD and antagonists changed soil microbial community structure to a larger extent. In conclusion, the applications of biocontrol agents and organic matter improved soil microbial community and decreased cucumber damping-off disease incidence, but the combination of RSD and the antagonists was a more promising method for the improvement of soil microbial community and the stable and successful control of the disease.

Although reductive soil disinfestation (RSD) is an effective method for suppressing Fusarium oxysporum, there is limited information on the relationships among types of organic matter, disinfestation efficiencies (DEs), and changes in soil functional microorganisms during the RSD process. Hence, we performed laboratory experiments using nine different organic materials and used quantitative real-time PCR and MiSeq pyrosequencing to investigate the suppression of F. oxysporum and changes in soil microbial communities during the RSD process. The results showed that the RSD treatments using different organic matters significantly decreased F. oxysporum populations in the soil, but DEs of the RSD treatments were dramatically different. Contents of easily oxidized organic carbon (EOC) in these plant residuals (sugarcane leaf, banana leaf, alfalfa, rice husk, wheat bran, reed, and sugarcane residue) had a significant positive correlation with the DEs and that in all of the organic matters had a significant positive correlation with total organic acid contents. The C/N values of these plant residuals had a significant negative correlation with DEs. Furthermore, the soil bacterial community during the alfalfa RSD process was significantly changed. In the early stage of the RSD treatment, relative abundances of Coprococcus (Firmicutes), UC-Clostridiaceae (Firmicutes), and Klebsiella (Proteobacteria) increased significantly and had a significant positive correlation with organic acids. In contrast, relative abundances of UC-Cytophagaceae (Bacteroidetes) and UC-Xanthomonadaceae (Proteobacteria) decreased significantly. In the later stage of the RSD treatment, the number of Opitutus (Verrucomicrobia) and UC-Clostridiales (Firmicutes) increased significantly. During the entire RSD process, relative abundances of decomposers of less-degradable organic carbon, such as UC-Chitinophagaceae (Bacteroidetes), Clostridium (Firmicutes), UC-Ruminococcaceae (Firmicutes), Pseudoxanthomonas (Proteobacteria), and Flavisolibacter (Bacteroidetes), were always higher than their initial relative abundance values. Overall, types of organic matter with lower C/N could induce higher DEs; organic matters with higher EOC could stimulate organic acid producers to produce more toxic organic acids and consequently induce higher DEs during the RSD process. Dominant functional microorganisms found during the alfalfa RSD treatment belonged to Firmicutes, Proteobacteria, and Bacteroidetes.

3,7-Diallyl-bispidin-9-one (6) (bispidin-9-one = 3,7-diazabicyclo[3.3.1]nonan-9-one) is converted to N-unsubstituted spiro[bispidin-9,2'-[1,3]dioxolane] (12; 35%). The ketal crystallizes in the forms of anhydrous 12a and the dihydrate 12b. The molecules in anhydrous 12a are linked to each other, forming N1-H1···N2-H2···N1* hydrogen-bond chiral helices of alternating chirality. In the dihydrate 12b, the ketal molecules are connected to a central string of water molecules by O3-H···O1 and O4-H···N1 hydrogen bonds, but not to themselves. Reaction of 12 with (1,5-hexadiene)PtCl2 affords almost quantitatively spiro[bispidin-9,2'-[1,3]dioxolane]PtCl2 (13). Cleavage of the ketal to retrieve the ketone produces the geminal diol (bispidin-9,9-diol)PtCl2 (14; 85%). Compound 14 reacts with Ag2cbdca (cbdca = 1,1-cyclobutanedicarboxylate) to give the dihydrate (bispidin-9,9-diol)Pt(cbdca)·2H2O (15b), which can be dehydrated to obtain anhydrous (bispidin-9,9-diol)Pt(cbdca) (15a). Similarly, anhydrous (bispidin-9,9-diol)Pt(oxalate) (16) is obtained. Crystal structures of 14 and 15b reveal association by various forms of O-H···O, O-H···Cl, N-H···Cl, and N-H···O hydrogen bonds. Biological studies showed a moderate cytotoxic activity of the bispidin-9,9-diol complexes 14-16, compared to the 9,9-unsubstituted bispidine complexes. No unspecific cytotoxicity of 14-16 up to 316 μM was found against the noncancer cell line HEK293.

A field campaign consisting of atmospheric boundary layer (ABL) observations and tracer experiments was conducted in September 2016 in a hilly region of the Gobi Desert in northwest China. High-frequency wind shears were observed between 70 and 200 m based on both 100-meter tower data and wind profiles. The ABL observations indicated that sub-layers of different atmospheric stability present within the ABL weakened the vertical transfer of momentum and tracer gas, resulting in low wind speed and high surface concentration. The CALMET model showed thermal heterogeneity to some extent in the temperature fields and mixing height distributions, and large deviations in the friction velocity between the model and observations were noted. The comparison of the CALPUFF model with the tracer measurements indicated a general tendency toward under-prediction of the concentration in the far distance because of wind shears and vertical thermal discontinuity. The results of the SCIPUFF model showed the same trend as those of CALPUFF, and comparisons demonstrated a good consistency of the two models.

Cui, H., 2020. Design of cruise tourism competitiveness evaluation system in port city. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 1075–1078. Coconut Creek (Florida), ISSN 0749-0208.The key issue in the development of cruise industry as a new economic growth point relies on the competitiveness of cruise ports. Based on comprehensive consideration of the internal and external conditions of cruise ports, the paper constructs a competitiveness evaluation system of cruise ports. The results show that the ports of developed cities in China have reached a high level, but the level of ports in developing cities is still poor. Furthermore, suggestions on enhancing the competitiveness of cruise ports are put forward, including accurately positioning port functions, improving related supporting facilities, improving service levels and building distinctive port brands.

Bispidine (3,7-diazabicyclo[3.3.1]nonane, C7H14N2) analogues of cisplatin, carboplatin, and oxaliplatin have been prepared. (C7H14N2)PtCl2·DMF (1b), obtained from (1,5-hexadiene)PtCl2 and bispidine in DMF, is dimeric in the solid state. Dissolving 1b in hot N-methylformamide allows crystallization of the solvent-free polymeric (C7H14N2)PtCl2 (1a). Recrystallization of 1a,b from hot water yields the trihydrate (C7H14N2)PtCl2·3H2O (1c). Reaction of 1 with Ag2(cbdca) (cbdca = 1,1-cyclobutanedicarboxylate) in water affords the pentahydrate (C7H14N2)Pt{C4H6(CO2)2}·5H2O (2b), which loses water in vacuo to give (C7H14N2)Pt{C4H6(CO2)2} (2a). Reaction of 1 with AgNO3 in water, followed by addition of Na2C2O4, affords the water-free polymeric (C7H14N2)Pt(C2O4) (3). All complexes have been structurally characterized, revealing various patterns of N-H···Cl and N-H···O hydrogen bonds. In the hydrates 1c and 2b the complexes are embedded in intricate three-dimensional water networks. Complexes 1a, 2a, and 3 have been tested for their cytotoxicity against human cancer cell lines K562 (chronic myeloid leukemia), A2780 (ovarian cancer), and its platinum-resistant subline A2780 CisR and are compared to their parent analogues. The new complexes show significant cytotoxic activity along with a low platinum resistance factor.

An effective degradation reaction of CH2Cl2 by bispidine (3,7-diazabicyclo[3.3.1]nonane, C7H12(NH)2, 1) is reported. The reaction starts as low as −20 °C and is quantitative with respect to 1. The overall reaction implies nucleophilic substitution of chloride, followed by a series of cascading acid–base reactions, ending with the formation of two easily separable products, one being soluble and the other insoluble. The starting 1, the intermediates, and the products show a variety of interesting solid-state structures, associated with plasticity, N–H⋯N and N–H⋯Cl⋯H–N hydrogen bonding, and polymorphism. Copyright © 2012 John Wiley & Sons, Ltd.

A novel Zn 2+ fluorescence probe, 2-[( N -ethyl carbazole)-3-sulfonyl ethylenediamine]-1- N , N -bis(2-methypyrbidy), was designed and synthesized via simple steps, and its structure was confirmed by IR and 1 H NMR. The probe gives significant fluorescence enhancement immediately following Zn 2+ addition at neutral pH and exhibits improved selectivity for Zn 2+ compared to the other metal ions in aqueous solution. The spectra and fluorescence quantum yield of the synthesized compound were carefully investigated by UV–vis absorption and fluorescence spectra in various solvents.

CALPUFF is an atmospheric source-receptor model recommended by the US Environmental Protection Agency (EPA) for use on a case-by-case basis in complex terrain and wind condition. As the bulk of validation of CALPUFF has focused on long-range or short-range but long-term dispersion, we can not gauge the reliability of the model for predicting the short-term emission in near-field especially complex terrain, and sometimes this situation is important for emergency emission. To validate the CALPUFF’s application in such condition, we carried out a tracer experiment in a near-field complex terrain setting and used CALPUFF atmospheric dispersion model to simulate the tracer experiment in real condition. From the centroid trajectory comparison of predictions and measures, we can see that the model can correctly predict the centroid trajectory and shape of tracer cloud, and the results also indicate that sufficient observed weather data only can develop a good wind field for near-field. From the concentration comparison in each arc, we can see the model underestimate horizontal extent of tracer puff and can not reflect the irregular characters showed in measurements. The result of global analysis is FOEX of −25.91%, FA2 of 27.06%, FA5 of 61.41%. The simulations shows that the CALPUFF can simulate the position and direction of tracer cloud in near-field complex terrain but underestimate over measurements especially in peak concentrations.

The synthesis of 3,7-diallyl-3,7-diazabicyclo[3.3.1]nonane (C7H12N2allyl2, 3) has been revisited, and several hitherto undetected byproducts have been identified. Pure 3 and these byproducts were isolated by both prep-GC and column chromatography. Monoprotonated 3 in the form of the PF6 salt [(C7H13N2allyl2]PF6 (9) and the addition complexes of 3 to Ni(acac)2 and CuI, (C7H12N2allyl2)Ni(acac)2 (10) and {(C7H12N2allyl2)Cu(μ-I)}2 (11), have been prepared. From the reactions of {(η3-C3H5)M(μ-X)}2 (M = Ni, Pd, Pt; X = Cl, Br) with 3 and TlPF6 the complexes [(C7H12N2allyl2)M(η3-C3H5)]PF6 (M = Ni (12a), Pd (12b), Pt (12c)) were obtained. Compounds 9–11 and 12b were characterized by X-ray crystallography. The reaction of (1,5-hexadiene)PtCl2 with 3 gave, after HCl elimination, monomeric {C7H12N2(C3H5)CH═CHCH2}PtCl (13a), and the presence of MeOH afforded {C7H12N2(C3H5)CH2CH(OMe)CH2}PtCl (13b), both compounds featuring novel anionic tridentate ligands. Furthermore, chiral N,N′-bis((R)-1-phenylethyl)-1,7-octadiene-...

The syntheses and structural characterization of methoxido- and ethoxido-vanadium complexes [VOCl2(OMe)(HOMe)2] (1), [VOCl(OMe)2]2 (2), and [{VOCl(OEt)2}2(THF)] (3) are described. The effects of the reactant ratio, starting materials, and reaction media on the formation of the alkoxido oxidovanadium and their molecular structures are reported. Complex 1 was prepared by reaction of VOCl3 with three equiv of MeOH in pentane. In the solid state, each molecule of 1 is linked with four symmetry related molecules through four O–H···Cl interactions resulting in the formation of a 2D infinite network. Reaction of VOCl3 with 2 equiv of NaOMe in pentane yields the dimeric complex 2, which features a pair of methoxido bridges in the molecular structure. In THF, reaction of VOCl3 with 2 equiv of NaOEt results in a very thermolabile [{VOCl(OEt)2}2(THF)] (3), which adopts a butterfly conformation in the molecular structure and features an interesting alkoxido oxidovandium with syn-orientated V=O functionality.

To explore the genotype distribution of 5,10-methylenetetrahydrofolate reductase (MTHFR) and 5-methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR) among Chinese Han women in Zhengzhou. A total of 1 253 women were recruited from Zhengzhou city. The genotype of MTHFR C677T, A1298C and MTRR A66G was detected to analyze the distribution of gene polymorphisms and to compare them with the published data from other Han women. The frequency of the MTHFR 1298CC genotypes (1.3%) in Zhengzhou was lower than that in Xiangtan (4.8%), Yanbian (3.8%), Zhenjiang (3.5%), Jingzhou (3.2%), Kunming (2.7%), Deyang (6.3%), Huizhou (7.2%) and Wulumuqi (3.4%) (all P0.05). The difference in allele frequency was significant compared with that in Yantai, Yanbian, Wulumuqi, Zhenjiang, Jingzhou, Kunming, Dezhou, Xiangtan or Huizhou (all P0.05). The frequency of the MTRR 66GG genotypes (5.4%) in Zhengzhou was lower than that in Deyang (8.2%) (P0.01) and allele frequency between them was significant difference (P0.05). The gene polymorphism of MTHFR A1298C and MTRR A66G among the Han women in Zhengzhou is statistically different from that in some regions of China.目的：探讨郑州市汉族女性5,10-亚甲基四氢叶酸还原酶(MTHFR)、甲硫氨酸合成酶还原酶(MTRR)基因多态性的频率特征。方法：以郑州市1 253例汉族女性为研究对象，检测MTHFR C677T，A1298C和MTRR A66G的基因分型。分析基因多态性的频率特征，并与已报道的其他地区汉族女性的数据进行比较。结果：郑州市汉族女性的MTHFR 1298CC纯合突变基因型频率(1.3%)低于湘潭(4.8%)、延边(3.8%)、镇江(3.5%)、荆州(3.2%)、昆明(2.7%)、德阳(6.3%)、惠州(7.2%)和乌鲁木齐(3.4%)等地(均P0.05)，等位基因与烟台、延边、乌鲁木齐、镇江、荆州、昆明、德州、湘潭、惠州等地差异有统计学意义(均P0.05)。MTRR 66GG纯合突变基因型频率(5.4%)低于德阳(8.2%)(P0.01)，等位基因与德阳差异有统计学意义(P0.05)。结论：郑州市汉族女性MTHFR A1298C和MTRR A66G基因多态性频率不同于其他地区，具有地域特异性。.

A series of cycloalkylidene-bridged cyclopentadienyl metallocene complexes, [(CH(2))(n)C(C(5)H(4))(2)MCl(2)] (M = Ti, n = 4 (4), 5 (5), 6 (6); M = Zr, n = 4 (7), 5 (8), 6 (9); M = Hf, n = 4 (10), 5 (11), 6 (12)), have been synthesized and applied to ethylene polymerization after activation with methyl aluminoxane (MAO). The cycloalkylidene-bridged titanocene catalysts exhibit much higher activities than the corresponding zirconocene and hafnocene analogues, and have the highest activities at higher temperatures. In comparison, the silacyclopentylidene-bridged metallocene complexes [(CH(2))(4)Si(C(5)H(4))(2)MCl(2)] (M = Ti (13), Zr (14)) and isopropylene-bridged metallocene complexes [Me(2)C(C(5)H(4))(2)MCl(2)] (M = Ti (15), Zr (16)) have also been synthesized and applied to ethylene polymerization. In both cases, the titanocene complexes show much higher activities than the corresponding zirconocene analogues, especially at a lower temperature. The molecular structures of complexes 4-9 have been determined by X-ray diffraction. The structure-activity relationships, especially the effects of the bridges of ansa-metallocene complexes, are discussed.

The reaction of 2-methoxyethanol or (2-methoxyethanolato)lithium with VOCl3 yields the chloro-bridged dinuclear complex [VOCl2(OCH2CH2OCH3)]2, which has been characterised spectroscopically and structurally by single-crystal X-ray diffraction analysis. This is the first reported structure of a neutral dinuclear oxovanadium complex connected by bridging chloro ligands. The orange complex is a precatalyst for the polymerisation of ethene and the oligomerisation of styrene. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

A dichloro oxovanadium(V) alkoxide complex [VOCl2(OCH2CH2OCH2CH2OnBu)] was synthesised by reaction of VOCl3 and 2-(2-butoxyethoxy)ethanol in pentane. It was characterised by IR, 1H, 13C and 51V NMR spectroscopy, mass spectrometry and elemental analysis. Single-crystal X-ray diffraction reveals a monomeric complex with all oxygen atoms of the ligand attached to the overall octahedrally coordinated vanadium atom. This complex exhibits remarkably higher activity than VOCl3 towards ethene polymerisation with diethyl aluminium chloride as co-catalyst and methyl trichloroacetate as promoter. The complex also catalyses the epoxidation of cyclooctene to cyclooctene oxide with tert-butyl hydroperoxide.

A novel Zn(2+) fluorescence probe, 2-[(N-ethyl carbazole)-3-sulfonyl ethylenediamine]-1-N,N-bis(2-methypyrbidy), was designed and synthesized via simple steps, and its structure was confirmed by IR and (1)H NMR. The probe gives significant fluorescence enhancement immediately following Zn(2+) addition at neutral pH and exhibits improved selectivity for Zn(2+) compared to the other metal ions in aqueous solution. The spectra and fluorescence quantum yield of the synthesized compound were carefully investigated by UV-vis absorption and fluorescence spectra in various solvents.