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Taking advantage of V-shaped ligands, a ZnII metallocryptand, namely {[Zn2(didp)2(m-bdc)2]} n , (1) [didp = 2,8-di(1H-imidazol-1-yl)-dibenzothiophene and m-H2bdc = isophthalic acid], has been hydrothermally synthesized. Single-crystal X-ray diffraction analysis reveals a 26-membered butterfly-type metallomacrocycle [Zn2(didp)2]. One m-bdc2− ligand bridges [Zn2(didp)2] units to form a laterally non-symmetric [Zn2(didp)2(m-bdc)] metallocryptand with an exo–exo conformation. Another crystallographically independent m-bdc2− functions as a secondary synthon to bridge discrete metallocryptands into a 1D zigzag chain architecture. Undoubtedly, the choice of two matched ligands in this work is crucial for metallocryptand construction and structure expansion. Interestingly, a rare helical chain with two flexures in one single L and/or R strand is observed. Another important feature is the C—O...π interactions, by which the dimensionality extension of (1) can be induced. Fluorescence measurements and density functional theory (DFT) calculations illustrate that the emission of (1) can probably be attributed to ligand-to-ligand charge transfer (LLCT).

Carbon nano-materials have been widely used in many fields due to their electron transport, mechanics, and gas adsorption properties. This paper introduces the structure and properties of carbon nano-materials the preparation of carbon nano-materials by chemical vapor deposition method (CVD)—which is one of the most common preparation methods—and reaction simulation. A major factor affecting the material structure is its preparation link. Different preparation methods or different conditions will have a great impact on the structure and properties of the material (mechanical properties, electrical properties, magnetism, etc.). The main influencing factors (precursor, substrate, and catalyst) of carbon nano-materials prepared by CVD are summarized. Through simulation, the reaction can be optimized and the growth mode of substances can be controlled. Currently, numerical simulations of the CVD process can be utilized in two ways: changing the CVD reactor structure and observing CVD chemical reactions. Therefore, the development and research status of computational fluid dynamics (CFD) for CVD are summarized, as is the potential of combining experimental studies and numerical simulations to achieve and optimize controllable carbon nano-materials growth.

A new copper-thiolate cluster assembled framework [Cu2(µ4-SCH3)Cl]n (1), has been solvothermally synthesized through in situ reaction viz., in situ ligand generation and metal reduction. Compound 1 represents the first 3D framework based on Atlas-sphere functionalized by single µ2-Cl− groups. DOS calculation reveals the interaction of electronic structures. It is found that the HOMO is mainly distributed on Cl, Cu and S bonding orbitals, while the LUMO is dominated by Cu-Cl antibonding orbitals.

Luminescent metal-organic frameworks (LMOFs), as one branch of MOFs, have attracted considerable attention in recent years due to their good crystallinity, structural diversity, tunable porosity and easily induced fluorescence emission. Importantly, their photoluminescence (PL) properties can be adjusted by altering metal ions or metal clusters and organic ligands in one hybrid system. Among the various sensing applications, using LMOFs as chemical sensors to detect the explosive and environment pollution causing nitroaromatic compounds (NACs) is an important topic. In this account, we describe the recent advancements in the field of NAC detection by LMOFs based on the triphenylamine (TPA) unit as the π-conjugated fluorophore.

Heavy metal ions pollution is one of the most dangerous and critical threats to human health and environment. In this work, three different generations of PAMAM dendrimer decorated on magnetic Fe 3 O 4 composites (Fe 3 O 4 @SiO 2 –G1, Fe 3 O 4 @SiO 2 –G3, Fe 3 O 4 @SiO 2 –G5) were fabricated and characterized by FTIR, XRD, TEM, and TGA. The obtained composites were used for Cr(VI) removal. Batch adsorption studies showed that the adsorption reached equilibrium within 60 min, and the optimal pH was 3.0. The result of adsorption kinetics was simulated by the pseudo–second-order model. The adsorption equilibrium isotherm was well fitted with the Langmuir adsorption model. Furthermore, thermodynamics calculations revealed that the adsorption process was endothermic and spontaneous. Importantly, adsorption capacity of Cr(VI) obey the sequence of Fe 3 O 4 @SiO 2 –G1＜Fe 3 O 4 @SiO 2 –G5＜Fe 3 O 4 @SiO 2 –G3, 3 generation of PAMAM (3G) is the optimal for adsorption capacity of Cr(VI). The maximum theoretical Cr(VI) adsorption capacity ( q m ) of Fe 3 O 4 @SiO 2 –G3 was 334.45 mg/g, and removal ration remained above 89.5% after five cycles of adsorption–desorption. Thus, Fe 3 O 4 @SiO 2 –G3 is predicted to be an efficient adsorbent for the adsorption of Cr(VI) from aqueous solution, and the obtained results can help in the generation optimization during fabrication of dendrimer modified adsorbents.

Three Co(II) metal-organic frameworks, namely, {[Co(L)(dpyb)0.5(H2O)2]·3H2O}n (1), {[Co(L)(dpyb)0.5]·CH3CN}n (2), and {[Co2(L)2(dpyp)1.5(H2O)]}n (3) have been hydrothermally synthesized based on a substituted thiophene carboxylic acid 3,3′-(thiophene-2,5-diyl)dibenzoic acid (H2L) and auxiliary N-donor co-ligands 1,4-di(pyridin-4-yl)benzene (dpyb) and 1,3-di(4-pyridyl)propane (dpyp). 1 possesses a 1D double chains structure, which is further extended into a 3D supramolecular framework via O–H···O hydrogen bonds and π···π interactions. 2 shows a novel 2D + 2D→ 2D network with unusual polyrotaxane entanglements of (4, 4)-sql subnets. The two sets of adjacent such networks are further extended via C–H···π interactions into a 3D supramolecular framework. 3 displays a non-interpenetrated 2D sheet with the point symbol {44.62} sql net topology and further extends via π···π interactions into a 3D supramolecular framework. The three MOFs were characterized by IR spectra, elemental analysis, thermal analysis and single crystal X-ray diffraction. In addition, solid-state UV–vis spectra experiments show that 1, 2, and 3 exhibit semiconductive properties with band gap of 2.23, 2.95, and 3.12 eV.

Two coordination polymers, namely [Mn(L)2(H2O)2]n (1) and [Cd2(L)4(H2O)4]n (2) {HL = (benzotriazol-1-yloxy)-acetic acid}, have been synthesized and characterized by single-crystal X-ray diffraction as well as with infrared spectroscopy and elemental analysis. The results reveal that CP1 has 1D double chain structure, while CP2 features a 1D infinite chain structure. Additionally, there both exist O–H···O and O–H···N hydrogen bonds in CP1 and CP2, forming 3D supramolecular structures, respectively. UV-vis absorption spectra of CP1, and photoluminescence property of CP2, have been examined in solid state at room temperature. The result on optical energy gap of 2.80 eV indicates that CP1 is a potential semiconductive material.

Two new isomorphous zinc(II) and nickel(II) supramolecular complexes, [Zn(L)2(H2O)2]n, (1), and [Ni(L)2(H2O)2]n (2) {HL = (benzotriazol-1-yloxy)-acetic acid} have been synthesized under ambient conditions by the self-assembly of HL with Zn(Ac)2·2H2O or Ni(Ac)2·4H2O in the presence of triethylamine. The two complexes have been characterized by single-crystal X-ray diffraction, elemental analysis, and IR spectroscopy. Single-crystal X-ray diffraction shows that the two complexes are isostructural and crystallize in monoclinic crystal system P21/c with similar unit-cell parameters and exhibit one-dimensional infinite chain structures. Adjacent chains are linked by O–H⋯O hydrogen bonds, giving rise to a two-dimensional network and these networks are further extended by weak π⋯π stacking interactions among adjacent aromatic cycles of HL ligands into a three-dimensional framework. In addition, the luminescent property of 1 and UV–Visible absorbance of 2 were also investigated and discussed. Density functional theory (DFT) calculations of the structures, stabilities, orbital energies, and composition characteristics of some frontier molecular orbitals of the two complexes were performed by means of Gaussian 09W package and taking B3LYP basis set.

The design and synthesis of coordination polymers with a self-penetrating architecture has attracted much interest not only due to their interesting structures but also due to their potential applications. 5,5′-Bis(pyridin-4-yl)-2,2′-bithiophene (bpbp), as a conjugated bithiophene ligand, can exhibit trans and cis conformations and this can lead to the construction of a self-penetrating architecture. In addition, the semi-rigid ancillary ligand 4,4′-oxybis(benzoic acid) (H2oba) can adopt different coordination modes, resulting in coordination polymers with high-dimensional skeletons. A new CdII coordination polymer based on mixed ligands, namely poly[diaquapentakis[μ-5,5′-bis(pyridin-4-yl)-2,2′-bithiophene-κ2 N:N′]bis(nitrato-κ2 O,O′)tetrakis(μ3-4,4′-oxydibenzoato)-κ10 O:O,O′:O′′,O′′′;κ6 O:O′:O′′-pentacadmium(II)], [Cd5(C14H14O5)4(NO3)2(C18H12N2S2)5(H2O)2] n , (I), has been synthesized under solvothermal conditions and characterized by single-crystal X-ray diffraction, IR spectroscopy and elemental analysis. Single-crystal X-ray diffraction indicates that there are three crystallographically independent CdII cations, three bpbp ligands, two deprotonated oba2− ligands, one nitrate ligand and one coordinated water molecule in the asymmetric unit. One CdII centre is seven-coordinated, exhibiting a distorted {CdN2O5} pentagonal bipyramidal geometry, while the other two Cd centres are both six-coordinated, showing slightly distorted {CdN2O4} octahedral geometries. The most interesting feature is the co-existence of trans and cis conformations in a single net, allowing structural interpenetration via self-threading and yet the expected self-penetrating structure was obtained. Topological analysis shows that the whole three-dimensional framework can be classified as a 3-nodal (4,6,6)-c net with Schläfli symbol {613.82}2{66}, which is a new topology. Furthermore, the luminescence properties of (I) were examined in the solid state at room temperature.

The combination of π-conjugated fluorophores within a hybrid system gives rise to a triphenylamine-functionalized material [Zn(bpba)(NO3)] (1) (Hbpba = 4-(bis(4-(pyridin-4-yl)phenyl)amino)benzoic acid). Compound 1 features a 2D + 2D → 2D parallel polycatenation structure with 63-hcb net. Photophysical studies revealed that the title phase showed superior sensitivity towards p-nitroaniline (p-NA) with a low detection limit (down to ∼0.10 ppm). Specifically, following a new detection route, vapor-sensing experiments using a saturated ethanol solution of nitroaromatic isomers have been established for the first time. Highly sensitive and selective detection of p-NA by the proposed material with a rapid response time (t = 30 s, QE > 90.0%) as compared to that via the control isomers (t = 60s, QE < 6.0%) demonstrates an attractive feasible route and a promising luminescent sensor for nitroaromatic detection.

Taking advantage of V-shaped ligands, a Zn

By employing the conjugated bithiophene ligand 5,5′-bis(1H-imidazol-1-yl)-2,2′-bithiophene (bibp), which can exhibit trans and cis conformations, two different CuII coordination polymers, namely, poly[[μ-5,5′-bis(1H-imidazol-1-yl)-2,2′-bithiophene-κ2 N:N′](μ2-4,4′-oxydibenzoato-κ2 O:O′)copper(II)], [Cu(C14H8O5)(C14H10N4S2)] n or [Cu(bibp)(oba)] n , (I), and catena-poly[μ-aqua-bis[μ-5,5′-bis(1H-imidazol-1-yl)-2,2′-bithiophene-κ2 N:N′]bis(μ3-4,4′-oxydibenzoato)-κ3 O:O′:O′′;κ4 O:O′,O′′:O′-dicopper(II)], [Cu2(C14H8O5)2(C14H10N4S2)(H2O)] n or [Cu2(bibp)(oba)2(H2O)] n , (II), have been prepared through one-pot concomitant crystallization and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis, powder X-ray diffraction (PXRD) and thermogravimetric (TG) analysis. Single-crystal X-ray diffraction indicates that the most interesting aspect of the structure is the existence of sole trans and cis conformations of the bibp ligand in a single net of (I) and (II), respectively. Compound (I) displays a threefold interpenetrating three-dimensional framework with a 4-connected {65.8} cds topology, whereas (II) features a one-dimensional chain structure. In the crystal of (II), the polymeric chains are further extended through C—H...O hydrogen bonds and C—H...π interactions into a three-dimensional supramolecular architecture. In addition, strong intramolecular O—H...O hydrogen bonds formed between the bridging water molecules and the carboxylate O atoms improve the stability of the framework of (II). Furthermore, solid-state UV–Vis spectroscopy experiments show that compounds (I) and (II) exhibit optical band gaps which are characteristic for optical semiconductors, with values of 2.70 and 2.26 eV, respectively.

BACKGROUND Riboflavin plus ultraviolet (UV) pathogen reduction technology (RF-PRT) is an effective method for inactivating the residual white blood cells (WBCs) in blood components. The RF-PRT system for platelets is known to activate many signaling pathways, including p38 and NF-κB. Nevertheless, proteomic studies in WBCs after riboflavin plus UV treatment requires further analysis. STUDY DESIGN AND METHODS ABO/D-matched lymphocytes were pooled, split, and treated with RF-PRT or UV light or left untreated. After treatment, cell apoptosis was measured. In addition, cell proliferation and the cycle distribution were evaluated upon stimulation with phytohemagglutinin. The changes in the protein expression levels of growth arrest and DNA damage-inducible (GADD)45α, p38, and c-Jun N-terminal kinase (JNK) were determined by Western blotting. The effect of GADD45α, p38, and JNK on apoptosis was assessed. RESULTS RF-PRT significantly inhibited proliferation and induced G1 arrest in lymphocytes. Furthermore, the percentage of apoptotic cells was increased in RF-PRT–treated lymphocytes compared to UV-treated cells or untreated cells, associated with the up regulation of GADD45α expression. Consistent with these observations, the inhibition of GADD45α expression partially counteracted the effects of riboflavin plus UV treatment. The p38 and JNK signaling pathways were activated by GADD45α in RF-PRT–treated lymphocytes. CONCLUSIONS These data revealed that RF-PRT effectively inhibited proliferation and induced apoptosis of lymphocytes by promoting GADD45α expression, which subsequently activates p38 and JNK signaling pathways.

Jian Fang,1,* Hao Wang,2,* Xiao Fang,3 Na Li,1 Hailiang Hu,1 Maohong Bian,1 Peng Yang1 1Department of Blood Transfusion, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, Anhui, China; 2Department of General Surgery and Translational Medicine Center, Nanjing Medical University Affiliated Wuxi Second Hospital, Wuxi 214002, Jiangsu, China; 3Department of Orthopaedics, Hefei Orthopaedics Hospital, Hefei 230000, Anhui, China *These authors contributed equally to this work Background: The expression of serine threonine tyrosine kinase 1 (STYK1), a member of the receptor protein tyrosine kinase (RPTK) family, is abnormal in several cancers. However, the molecular mechanism of STYK1 regulation of gastric cancer (GC) progression is unknown.Materials and methods: We evaluated STYK1 expression in GC tissues and the corresponding normal tissues. Specimens from 93 patients with GC were examined with immunohistochemical staining. The relationship between STYK1 protein expression and the patients’ clinicopathological features was assessed. Kaplan–Meier and Cox proportional regression analyses were used to evaluate the association between STYK1 expression and survival.Results: STYK1 expression was decreased in GC tissues. Low STYK1 expression was significantly associated with poor tumor differentiation (P=0.023), advanced clinical stage (P=0.021), and poor overall survival (OS; P=0.034). Univariate and multivariate analyses revealed that STYK1expression was an independent prognostic indicator (HR =0.53, 95% CI =0.29–0.95, P=0.039; HR =0.51, 95% CI =0.24–0.91, P=0.030, respectively).Conclusion: Downregulated STYK1 expression correlated significantly with poor tumor differentiation, advanced clinical stage, and poor OS in GC. STYK1 might be a diagnostic and prognostic indicator in patients with GC. Keywords: gastric cancer, STYK1, prognosis, overall survival

To evaluate the performance of thromboelastography (TEG) to monitor in vivo blood coagulation status and the efficacy of antiplatelet aggregation drugs in the patients with coronary heart disease (CHD) after oral anticoagulation.Seventy one CHD patients were enrolled in CHD group and 380 healthy persons with normal TEG were enrolled in the control group. After admission, all CHD patients were administrated with routine anti-platelet aggregation drugs at a clinically recommended dose. Then, TEG was applied to monitor the basic blood coagulation indexes, such as R value, K value, α angle, MA value, CI value and a series of related indexes on platelet inhibition.Above 80% of the basic blood coagulation indexes in TEG were within normal reference range in the CHD group. the R value, MA value, α angle and CI value in the CHD group were not significanly different, from that in the control group, but the K value significantly increased (P0.05). Compared with the control group, relatively higher ratio of male was included in the CHD patients at much older age (P0.05), 83.1% of the CHD patients achieved significant anti-platelet aggregation effect (platelet inhibition rate50%). Other antiplatelet aggregation indexes, MATEG results can provide valuable coagulation information for clinicians, thus certainly guiding in the treatment for CHD patients receiving anti-platelet therapy. Moreover, the application of TEG can also provide accurate information for further individualized treatment of CHD patients, which would funther inprove the safety of anti-thrombotic therapy.

Rough set theory is a popular mathematical knowledge to resolve problems which are vagueness and uncertainly. And it has been used of solving the redundancy of attribute and data. Decision tree has been widely used in data mining techniques, because it is efficient, fast and easy to be understood in terms of data classification. There are many approaches have been used to generate a decision tree. In this paper, a novel and effective algorithm is introduced for decision tree. This algorithm is based on the core of discernibility matrix on rough set theory and the degree of consistent dependence. This algorithm is to improve the decision tree on node selection. This approach reduces the time complexity of the decision tree production and space complexity compared with ID3.In the end of the article, there is an example of the algorithm can exhibit superiority.

The design and synthesis of coordination polymers with a self-penetrating architecture has attracted much interest not only due to their interesting structures but also due to their potential applications. 5,5'-Bis(pyridin-4-yl)-2,2'-bithiophene (bpbp), as a conjugated bithiophene ligand, can exhibit trans and cis conformations and this can lead to the construction of a self-penetrating architecture. In addition, the semi-rigid ancillary ligand 4,4'-oxybis(benzoic acid) (H

BACKGROUND: The assessment of the coagulation status using thromboelastography (TEG) in Chinese population has less been reported. This study aimed to establish reliable reference values for kaolin‐activated TEG in Chinese volunteers. METHODS: A total of 1681 Chinese adult individuals were recruited for this study. The reference individuals were stratified by gender and age, and the TEG values were measured on the basis of strict quality control. The 95% reference values were determined using nonparametric statistical methods. RESULTS: The sex‐related 95% reference values were reaction time (R):4.2‐8.7 minutes; clotting time (K): 1.2‐3.2 minutes; alpha angle (α): 47.0‐72.3 degree; maximum amplitude (MA): 49.1‐70.5 mm for males, and R: 3.7‐9.0 minutes; K: 1.0‐3.2 minutes; α: 48.4‐74.4 degree; MA: 46.8‐72.4 mm for females. Also, the TEG parameters indicated a relatively more hypercoagulable profile in both female and elder groups. CONCLUSIONS: This study established the reference values for kaolin‐activated TEG in the target Chinese population, which might provide a reference for both clinical and laboratory studies.

NodD is the major regulator of nod genes expression in rhizobia. Previously, a HU-like protein in Rhizobium leguminosarum bv. viciae has been identified to bind specifically with nod promoters and be involved in in vitro nodD transcription, but its in vivo function remained unknown. In this work we have cloned and sequenced the R. leguminosarum bv. viciae gene, named hurL, for this HU-like protein. Using the E. coli-expressed HurL proteins, we proved that HurL had high affinity to several nod promoters and showed a stimulation effect on in vitro nodD transcription at appropriate concentration. The R. leguminosarum bv. viciae hurL gene was mutated by insertion of a kanamycin resistance cassette. The obtained hurL mutant strain M704 exhibited poor growth under free-living conditions and failed to induce nodules on Pisum sativum cv. Frisson and Vicia hirsuta. Further studies of NodD production and nod genes-lacZ fusions expression in the hurL mutant revealed that inactivation of hurL led to severe impairment in the nodD expression, repression in the inducible expression of nodA and nodF, and slight enhancement in the expression of px2, a gene identified earlier in this lab. These results suggested that hurL might be required for maintaining the normal expression of nod genes in R. leguminosarum bv. viciae.

In Rhizobium leguminosarum, NodD can activate nodA transcription in response to inducer flavonoids. Here, we show that the inducible nodA promoter contains an intrinsic part through which NodD can activate nodA transcription in an inducer-independent manner. Evidence was provided that NodD binds to target DNA through anchoring the two half-sites of the nod box as a tetramer. An imperfect inverted repeat AT-N10-GAT was found in each half-site and is critical for NodD binding. Mutation of the inverted repeat of the nod box distal half-site allowed NodD to activate nodA transcription in an inducer-independent manner in vivo, and to modulate the DNA bending of the NodD-nod box complex in the absence of inducer in vitro.

A Rhizobium expression system was constructed via introducing strong transcriptional elements to an IncP broad host range plasmid pKT230. Using this system, the nodD gene of Rhizobium leguminosarum biovar viciae was overexpressed in its own in vivo environment. Western blot showed that the NodD yield of the newly constructed expression vector pKNDT was much higher than that of a reported vector pIJ1518. Based on the result from quantitative gel retardation assay, the specific DNA-binding activity of NodD was estimated to increase by about 80-fold. Purification of NodD was performed by the sequential steps: polyethyleneimine treatment, ammonium sulfate fractional precipitation, and cellulose phosphate P11 chromatography. About 26 mg NodD with a purity about 90% was obtained from 14 g wet weight cell pellet within 2 days.

NodD is the major regulator of nod genes expression in rhizobia. Previously, a HU-like protein in Rhizobium leguminosarum bv. viciae has been identified to bind specifically with nod promoters and be involved in in vitro nodD transcription, but its in vivo function remained unknown. In this work we have cloned and sequenced the R. leguminosarum bv. viciae gene, named hurL, for this HU-like protein. Using the E. coli-expressed HurL proteins, we proved that HurL had high affinity to several nod promoters and showed a stimulation effect on in vitro nodD transcription at appropriate concentration. The R. leguminosarum bv. viciae hurL gene was mutated by insertion of a kanamycin resistance cassette. The obtained hurL mutant strain M704 exhibited poor growth under free-living conditions and failed to induce nodules on Pisum sativum cv. Frisson and Vicia hirsuta. Further studies of NodD production and nod genes-lacZ fusions expression in the hurL mutant revealed that inactivation of hurL led to severe impairment in the nodD expression, repression in the inducible expression of nodA and nodF, and slight enhancement in the expression of px2, a gene identified earlier in this lab. These results suggested that hurL might be required for maintaining the normal expression of nod genes in R. leguminosarum bv. viciae.

The expression of nod genes of rhizobia is controlled at the transcriptional level in a complicated way. In this work, a new promoter, which is responsible for an RNA molecule transcription in the opposite direction to that of nodF, was identified in Rhizobium leguminosarum. This new promoter was characterized to overlap with that of nodF, and the size of px(2), the RNA molecule initiated from this promoter was determined to be of approximately 0.72 kb in length. The study on px2 showed that its transcription depended on the Escherichia coli sigma(70)- like factor of Rhizobium leguminosarum, and that the in vitro transcription of px(2) was inhibited by Px, a newly identified regulatory protein in our lab. The involvement of px(2) in the regulation of nod gene expression is suggested.