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We synthesized three new Ni(II) coordination polymers [Ni(L)(HIP)(H2O)2]H2O(CP1), [Ni(L)(NIP)]·2H2O(CP2) and [Ni(L)(NDC)(H2O)2](CP3)[L=N,N'-bis(pyridine-3-yl)thiophene-2,5-dicarboxamide, H2HIP=5-hydroxyisophthalic acid, H2NIP=5-nitroisophthalic acid, H2NDC=2,6-naphthalenedicarboxylic acid] by hydrothermal method, which were characterized by means of infrared spectra(IR), TG analyses, PXRD and single-crystal X-ray diffraction. The CP1 is a 1D tubular structure based on [Ni-HIP]2 loops and pairs of L ligands. CP2 is a 2D 3,5-connected architecture, which consists of Ni-L linear chains and (Ni-NIP)2 double chains. CP3 is a 2D network, which features 4-connected topology. Solid-state luminescent behaviours of CP1—CP3 were investigated. The CP1 can detect Fe3+ ions through luminescence quenching. The electrochemical properties of CP1 buk-modified carbon paste electrode(CP1-CPE) has also been investigated, which has bifunctional electrocatalytic activity for oxidation of ascorbic acid and reduction of NO2−.

Three new polyoxometalate (POM)-based metal–organic complexes, {Ni3(Hpytty)2[AlMo6(OH)5O19](H2O)4(CH3O)}·5H2O (1), {Ni3(Hpytty)2 [CrMo6(OH)5O19](H2O)10}·6H2O (2), and {Co2(pytty)[γ-Mo8O26]0.5 (H2O)5}·4H2O (3) (H2pytty = 3-(pyrazine-2-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl), have been prepared by the solvothermal method. Complexes 1 and 2 show similar 0-D structures containing a [Ni3(Hpytty)2]4+ and Anderson-type [AlMo6(OH)5O19]4− /[CrMo6(OH)5O19]4− anions. The [γ-Mo8O26]4− anion was generated in-situ from the [IMo6O24]5− anion in 3, which shows a 3-D coordination structure constructed from 2-D Co-pytty metal–organic layers and γ-Mo8 anions. The results reveal that the POMs play key roles in tuning the diverse architectures of the final complexes. For 1–3, their adsorption properties for MB/GV and their electrochemical activities have been investigated.

The signal transducer and activator of transcription 3 is a constitutively activated oncogenic protein in various human tumors and represents a valid target for anticancer drug design. In this study, we have achieved a new type of STAT3 inhibitors based on structural modifications on shikonin scaffold, guided by computational modelling. By tests, PMMB-187 exhibited a more outstanding profile than shikonin on a small panel of human breast cancer cells, especially for the MDA-MB-231 cells. For the cellular mechanisms research, PMMB-187 was found to induce cell apoptosis in MDA-MB-231 cells, associated with the reduction of mitochondrial membrane potential, production of ROS and alteration of the levels of apoptosis-related proteins. Furthermore, PMMB-187 inhibited constitutive/inducible STAT3 activation, transcriptional activity, nuclear translocation and downstream target genes expression in STAT3-dependent breast cancer cells MDA-MB-231. Besides, no obvious inhibitory effect on activation of STAT1 and STAT5 was observed with PMMB-187 treatment. Most notably, the in vivo studies further revealed that PMMB-187 could dramatically suppress the MDA-MB-231 cells xenografted tumor growth. The in vitro and in vivo results collectively suggest that PMMB-187 may serve as a promising lead compound for the further development of potential therapeutic anti-neoplastic agents.

Three different dimensional Ni(II) coordination polymers, [Ni(3-pna)(HIP)(H2O)3]·H2O(1), [Ni(3-pna)· (1,3,5-HBTC)](2) and [Ni2(H2O)(3-pna)2(1,4-CHDC)2]4(3)(3-pna=3-pyridylnicotinamide, H2HIP=5-hydroxyisophthalic acid, 1,3,5-H3BTC=1,3,5-benzenetricarboxylic acid, 1,4-H2CHDC=1,4-cyclohexanedicarboxylic acid), were synthesized under hydrothermal conditions and characterized by means of infrared spectra(IR), thermal gravimetric (TG) analyses, powder X-ray diffraction(PXRD) and single-crystal X-ray diffraction. Complex 1 has a structure of 1D single-stranded chain, which is further stretched by hydrogen-bond interactions to form a 2D supramolecular sheet. Complex 2 shows a 2D network, which is stretched to 3D supramolecular frameworks through hydrogen-bond interactions. Complex 3 reveals a 3D skeleton with a (3,3,6,6)-connected {3·72}{32·4}{33·42·5·73·85·9}{33·45·52·72·82·9} topology. The effects of different polycarboxylates on the ultimate architectures of the complexes 1—3 were discussed. Furthermore, the fluorescent and photocatalytic properties of the title complexes were also investigated.

Three Cd(II) metal-organic complexes, namely [Cd(phen)2Cl2](1), [Cd(phen)Cl2](2) and [Cd(phen)(cam)]· H2O(3)(phen=1,10-phenanthroline, H2cam=camphoric acid), were hydrothermally synthesized using Cd2+, phen and H2cam as raw materials under different conditions of pH values, reaction temperatures or reactant ratios. The prepared complexes were structurally characterized by means of single-crystal X-ray diffraction, and the results show that complex 1 is a 2D supramolecular complex, which consists of [Cd(phen)2Cl2] mononuclear subunits, while complex 2 shows a 1D chain structure, in which Cd(II) ions are connected by chloride(Cl–) bridges, with phen hanging on both sides of the chain. No cam anions have been observed in the structures of complexes 1 and 2. In complex 3, cam connects Cd(II) ions to construct a 2D network, in which phen acts as terminal ligands. The adjacent 1D chains for complex 2 and the adjacent 2D layers for complex 3 are further linked by hydrogen bonding interactions or π-π intermolecular interactions to form 3D supramolecular networks, respectively. The effects of reaction conditions on the assembly and structures of the complexes have been discussed. The fluorescent and photocatalytic properties of complexes 1―3 and the fluorescent sensing behaviors of complexes 2 and 3 have also been investigated.

Shikonin exhibits powerful anticancer activities for various cancer cells, but its poor solubility and strong toxicity hinder its development as clinical anticancer agent. We previously confirmed that shikonin and its derivatives can disturb mitosis through targeting tubulin. In this study, α-lipoic acid, the naturally-occurring co-factor of pyruvate dehydrogenase (PDH), was introduced into shikonin to design the twin drugs against both mitosis (tubulin) and glycolysis (PDK). 18 kinds of α-lipoic acid shikonin ester derivatives were achieved through three rounds of screening process performed by computer assistant drug design method, being designated as the outstanding compounds. Among them, 1c displayed the most potent cytotoxicity towards cervical cancer cells (HeLa) with an IC50 value of 3.14 ± 0.58 μM and inhibited xenotransplanted tumor growth in a dose-dependent manner. Further pharmacologic study demonstrated that 1c can cause cell cycle arrest in G2/M phase as tubulin polymerization inhibitor. Moreover, it also showed good PDK1 inhibitory activity, promoting PDH activity and forced HeLa cells to process more aerobic metabolism to undergo cell apoptosis. We reported here the first dual inhibitors of tubulin and PDK1 based on shikonin. It may form a basis for shikonin optimization through twin drug design framework for the discovery of new and potent shikonin derivatives in the study of targeted cancer therapy.

Mobile shopping is increasing in prevalence and has become a necessary part of many people's daily lives. However, one main channel for mobile shopping, mobile shopping applications (apps), has not been thoroughly investigated. This study focused on mobile text advertising delivered from mobile shopping apps using the intention to purchase as the dependent variable for testing its marketing effect. In the context of a promotion focus vs. a prevention focus, we used Higgins' regulatory focus theory combined with Ajzen's TPB and Herzog's U&G to analyze the mechanism by which consumers formulate an intention to purchase in a mobile advertising context. This empirical study surveyed 320 consumers who had made a purchase using a mobile shopping app in the previous month. The results showed that infotainment, irritation, and subjective norms were significantly associated with attitudes; in turn, attitudes mediated the impact of these three factors on the intention to purchase. Moreover, a high promotion focus not only strengthened the positive effect of infotainment on attitudes but also intensified the mediation effect of attitudes between infotainment and the intention to purchase. A high prevention focus also consolidated the negative effect of irritation on attitudes as well as reinforced the mediation effect of attitudes between irritation and the intention to purchase. Furthermore, attitudes, subjective norms, and perceived behavioral control collectively impacted the intention to purchase. These findings shed light on ways to customize goods information in mobile advertising and have strong theoretical and practical implications.

In this paper, a series of podophyllotoxin piperazine acetate ester derivatives were synthesized and investigated due to their antiproliferation activity on different human cancer cell lines. Among the congeners, C5 manifested prominent cytotoxicity towards the cancer cells, without causing damage on the non-cancer cells through inhibiting tubulin assembly and having high selectively causing damage on the human breast (MCF-7) cell line (IC50=2.78±0.15μM). Treatments of MCF-7 cells with C5 resulted in cell cycle arrest in G2/M phase and microtubule network disruption. Moreover, regarding the expression of cell cycle relative proteins CDK1, a protein required for mitotic initiation was up-regulated. Besides, Cyclin A, Cyclin B1 and Cyclin D1 proteins were down-regulated. Meanwhile, it seems that the effect of C5 on MCF-7 cells apoptosis inducing was observed to be not obvious enough. In addition, docking analysis demonstrated that the congeners occupy the colchicine binding pocket of tubulin.

According to the samples of 1781 literatures about environmental impact assessment (EIA) of SCI and SSCI databases from 1973 to 2009, this paper analyzes the literatures in their trend of growth, subject categories and journals, International collaborations, geographic distribution of publications and scientific research issues by using bibliometrics analysis. The result shows that EIA research steadily increases over the past 40 years and the annual number of papers published in 2009 is 50 times than that in 1973. EIA was involved into 130 kinds of subjects and appeared in 587 journals. The main study area with strong scientific research capabilities distributed in USA and European Union, while the USA was the largest contributor in EIA research and had a central position in collaboration networks. A keyword analysis found that the priority in assessment would gradually change from project environmental impact assessment to Strategic Environmental Assessment (SEA) and Plan Environmental Impact Assessment (PEIA); EIA research would focus on using and improving new techniques and methods, such as “life cycle assessment (LCA)”, “geographic information system (GIS)” and “modeling” etc.; “biodiversity” and “climate change” would attract more attention and will be the emphasis of EIA; the improvement of developing countries’ EIA system became popular research. This study reveals patterns in scientific outputs and academic collaborations and serves as an alternative and innovative way of identifying global research trends in EIA.

The high incidence of cancer and the side effects of traditional anticancer drugs motivate the search for new and more effective anticancer drugs. In this study, we synthesized 17 kinds of aryl dihydrothiazol acyl shikonin ester derivatives and evaluated their anticancer activity through MTT assay. Among them, C13 showed better antiproliferation activity with IC50=3.14 ± 0.21 μM against HeLa cells than shikonin (IC50=5.75 ± 0.47 μM). We then performed PI staining assay, cell cycle distribution, and cell apoptosis analysis for C13 and found that it can cause cell arrest in G2/M phase, which leads to cell apoptosis. This derivative can also reduce the adhesive ability of HeLa cells. Docking simulation and confocal microscopy assay results further indicated that C13 could bind well to the tubulin at paclitaxel binding site, leading to tubulin polymerization and mitotic disruption.

In this study, a coupling model of agricultural and urban non-point source (AUNPS) is established in order to estimate complex non-point source (NPS) pollutant loads in the urban–rural fringe. Furthermore, a spatial–temporal change model of non-point source (CA-AUNPS) is established by the coupling of AUNPS and cellular automata (CA) models. The total nitrogen (TN) and total phosphorus (TP) loads in Tangxun watershed were simulated during 1991–2020, and the results show that: (1) the CA-AUNPS model is an effective tool to simulate the spatial–temporal changes of NPS pollutant loads in urban–rural fringe; (2) in terms of the spatial changes, the TN and TP loads generally showed as rural/urban construction land > farmland > forest/green land, and the high-value areas of NPS pollutant loads expanded from north to south with the increase of construction land; with regard to temporal changes, the TN and TP loads generally displayed an increasing tendency during 1991–2020, and by 2020 the TN and TP loads will increase to 370.06 and 33.89 t yr−1, respectively; (3) the spatial–temporal changes of TN and TP loads in Tangxun watershed correlate strongly with the land-use, slope, and rainfall.

Through establishing the multi-duty principal-agent model, this article has analyzed the influences to firm performance by different performance incentive, and research the relevance between the different performance index. Furthermore, this model quantitative analysis the quantitative relations which influence the firm performance index. According the model, it can confirm the pay contract and can soundly direct how to effectively weight the performance of the staff.

The strain, Burkholderia vietnamiensis C09V was immobilized on PVA-alginate-kaolin gel beads as a biomaterial to improve the degradation of crystal violet from aqueous solution. The results show that 98.6% (30 mg L−1) crystal violet was removed from aqueous solution using immobilized cells on PVA-alginate-kaolin gel beads, while 94.0% crystal violet was removed by free cells after degradation at the pH 5 and 30 °C for 30 h. Kinetics studies show that the pseudo-second-order kinetics well described the adsorption of crystal violet on the PVA-alginate-kaolin beads. Biodegradation of crystal violet on immobilized cells was fitted well by first-order reaction kinetics, indicating that CV was adsorbed onto kaolin and followed their degradation by immobilized cells onto the the PVA-alginate-kaolin beads. Characterization with SEM shows that cells attached well to the surface of PVA-alginate-kaolin beads, leading to improved crystal violet transfer from aqueous solution to immobilized cells. In addition, UV-vis show that the absorption peak at 588 nm was reduced by the degraded N-bond linkages, as well as the formation of degrading products were observed by Fourier transform infrared (FTIR). These results suggest that crystal violet was biodegraded to N,N-dimethylaminophenol and Michler's Ketone prior to these intermediates being further degraded. Refereed/Peer-reviewed