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Cluster-based functional materials have made remarkable progress owing to their wonderful structures and distinctive physicochemical performances, one of on-going advancements of which is basically driven by synthetic chemistry of exploring and constructing novel nanosized gigantic polyoxometalate (POM) aggregates. In this article, an unprecedented nanoscale hexameric arsenotungstate aggregate Na9K16H4[Er0.5K0.5(H2O)7][Er5W10O26(H2O)14][B-α-AsW9O33]6·102H2O (1) has been synthesized by the combined synthetic strategy of simultaneously using the arsenotungstate precursor and simple tungstate material in a highly acidic aqueous solution. The {[Er5W10O26(H2O)14][B-α-AsW9O33]6}31− polyanion in 1 consists of an intriguing dumbbell-shaped pentadeca-nuclear W-Er heterometal {Er5W10O26(H2O)14}23+ cluster connecting six trilacunary [B-α-AsW9O33]9− moieties, which has never been seen previously. Furthermore, through electropolymerization of 1 and pyrrole on the conductive substrate, a thickness-controllable and robust 1-PPY (PPY = polypyrrole) hybrid film was successfully prepared, which represents the first POM-PPY film assembled from high-nuclear lanthanide (Ln) encapsulated POM and PPY hitherto. The 1-PPY film-based electrochemical biosensor exhibits a favorable recognition performance for ochratoxin A in multiple media. This work not only provides a feasible combined synthetic strategy of the POM precursor and simple tungstate material for constructing complicated multi-Ln-inserted POM aggregates, but also offers a promising electrochemical platform constructed from POM-based conductive films for identifying trace biomolecules in complex environments. [ABSTRACT FROM AUTHOR]

By introducing rigid aromatic N-ligands to the lacunary silicotungstate system under hydrothermal conditions, two new Keggin-type polyoxotungstate hybrids with copper-organic complexes [Cu(phen)(HO)][Cu(phen)][α-SiWO]·4HO ( 1) and [Cu(4,4′-bpy)]H[α-SiWO]·3 HO ( 2) (phen = 1,10-phenanthroline, 4,4′-bpy = 4,4′-bipyridine) have been made and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The common architectural feature of 1 and 2 is that both comprise the plenary Keggin-type [α-SiWO] polyoxoanions modified by Cu-organic fragments containing various organic ligands. It should be pointed out that {[Cu(phen) (HO)][α-SiWO]} and {[Cu(phen)][α-SiWO]} building units in 1 are alternately held together into an infinite 1-D chain fashion while the most striking characteristic of 2 is that two types of {-4,4′-bpy-Cu- 4,4′-bpy-Cu-} 1-D polymeric chains are combined together by hexadentate [α-SiWO] polyoxoanions as the inorganic bridging ligands, giving birth to the aesthetic 3-D extended architecture. Moreover, electrochemical properties of 1 and 2 have been investigated. [ABSTRACT FROM AUTHOR]

An organic -inorganic hybrid polyoxovanadoborate K(CHNH)[VBO(OH)-(HO)]·2en·12HO ( 1, en = ethylenediamine) has been synthesized under hydrothermal conditions and characterized by IR spectroscopy, element analyses, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. Single-crystal structure analysis reveals that 1 consists of a cage-like polyoxovanadium borate [VBO(OH)(HO)] cluster that is constructed from a puckered {BO(OH)} ring sandwiched by two triangle {VO} units, in which a water molecule is confined in the middle of the cage-like cluster. Interestingly, 1 represents the rare example of extended 3-D framework constructed from [VBO(OH)-(HO)] clusters through K cations. [ABSTRACT FROM AUTHOR]

Two novel hexa-nickel(II)-substituted Keggin-type {NiPW}-based tungstophosphates [Ni( μ-Tris)(en)( Pr)(damp)(HO)(B- α-PWO)]·10HO ( 1) and [Ni( μ-Tris)(en)(damp)(HO)(B- α-PWO)]·7HO ( 2) (en = ethylenediamine, Pr = CHCHCOO, damp = 2-aminoisobutyrate, Tris = pentaerythritol) were hydrothermally synthesized and characterized by IR spectra, elemental analyses, powder X-ray diffraction, thermogravimetric analyses, and single-crystal X-ray diffraction. Crystal data for 1: orthorhombic, Pca2, a = 21.6962(7) Å, b = 20.6398(5) Å, c = 14.7825(4) Å, β = 90º, V = 6619.7(3) Å, Z = 4; for 2: orthorhombic, Pca2, a = 21.6978(9) Å, b = 20.6658(7) Å, c = 14.7767(4) Å, β = 90º, V = 6625.9(4) Å, Z = 4. 1 consists of a {Ni( μ-Tris)(en)( Pr)(damp)(HO)} core and a [B- α-PWO] (PW) unit and is covalently functionalized by one Pr and one damp, as well as en and Tris ligands. The structure of 2 is the same to 1 except that the Pr anion in 1 is substituted by the other damp ligand. Most interestingly, 1 contains four kinds of organic ligands, while 2 includes three kinds of organic ligands, which are first observed in polyoxometalate chemistry. [ABSTRACT FROM AUTHOR]

Hydrothermal reactions of trilacunary precursor A- α-AsWO polyoxoanions and nickel ions in the presence of ethylenediamine (en = ethylenediamine) led to two new hexa-Ni-substituted Keggin-type tungstoarsenates [Ni( μ-OH)(en)(HO)(B- α-AsWO)]·6HO ( 1) and [Ni( μ-OH)(en)(HO)(B- α-AsWO)]·10HO ( 2), which have been characterized by elemental analyses, IR spectra, powder X-ray diffraction, thermogravimetric analyses and single-crystal X-ray diffraction. Crystal data for 1: hexagonal, R3 c, a = b = 20.4379(5) Å, c = 21.5062(6) Å, β = 120º, V = 7779.8 (3) Å and Z = 6; for 2: momoclinic, P2/ c, a = 13.4200(3) Å, b = 19.1428(5) Å, c = 22.8845(9) Å, β = 112.403(3)º, V = 5435.2(3) Å and Z = 4. Structural analyses reveal that the [Ni( μ-OH)(B- α-AsWO)] clusters in 1 and 2 are covalently functionalized by neutral en ligands, in which two similar {Ni( μ-OH)(en)(HO)} cores have been observed by our lab. Notably, 1 and 2 represent the highest number of substituted transition metal ions in all known lacunary Keggin-type polyoxotungstoarsenate monomers. [ABSTRACT FROM AUTHOR]

Two Co-substituted sandwich-type polyoxometalates (Hen)[Co(HO)(PWO)]{[Co(HO)][Co(HO)(PWO)]}·18HO ( 1) and (Hen)[Co(HO)(HGeWO)]{[Co(HO)][Co(HO)(HGeWO)]}·16HO ( 2) (en = ethylenediamine) have been hydrothermally synthesized and characterized by IR spectra, elemental analyses, thermogravimetric analyses, powder X-ray diffraction and single-crystal X-ray diffraction. Single-crystal structure analysis reveals that the molecules of 1 and 2 contain two Co-substituted sandwich-type polyoxoanions. This type of a molecular unit containing double polyoxoanions is very rare. From the viewpoint of supramolecular chemistry, the sandwich-type polyoxoanions in 1 and 2 can be further extended to 3-D frameworks via extensive hydrogen-bonding interactions. [ABSTRACT FROM AUTHOR]

Four new hexa-nickel(II)-substituted Keggin-type tungstophosphates [Ni(μ-OH)(oeen)(HO)(B-α-PWO)]·6HO ( 1, oeen = N-(2-hydroxyethyl)enediamine), [Ni(μ-OH)(oeen)(HO)(B-α-PWO)]·13HO ( 2), [Ni(μ-OH)(oeen)(tran)(HO)(B-α-PWO)]·3HO ( 3, tran = 1,4,7-triazonane) and [Ni(μ-OH)(oeen)(tran)(HO)(B-α-PWO)]·6HO ( 4) have hydrothermally made by controlling their reaction temperatures. 1- 4 have been characterized by elemental analyses, IR spectra, powder X-ray diffraction, thermogravimetric analyses and single-crystal X-ray diffraction, respectively. Structural analyses reveal that they consist of {Ni(μ-OH)(HO)} cores and B-α-PWO (PW) units, and further are stabilized by organic neutral oeen/tran molecules. 1- 3 are isolated clusters while 4 is the 1D chain structure. It should be noted that the tran molecules in 3 and 4 are derived from the oeen molecules in the starting materials. [ABSTRACT FROM AUTHOR]

A tetra-Co substituted sandwich-type polyoxotungstate (HTED)Cs[Co(HO)(B- α-HPWO)]·28HO (TED = triethylenediamine) has been hydrothermally synthesized and characterized by IR spectrum, elemental analysis, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction, respectively. Single-crystal structure analysis reveals that the tetra-Co substituted sandwich-type phosphotungstate units [Co(HO)(B- α-PWO)] are combined together by Cs cations giving rise to the 3D framework with the 'sqc876' 3D net. [ABSTRACT FROM AUTHOR]

Two new organic-inorganic hybrid carboxylate-bridging copper-lanthanide heterometallic polyoxotungstates K[Cu(en)(HO)]{[Cu(en)][Ce(GeWO)(HO)](CO)}·11HO ( 1) and K [Cu(en)(HO)]{[Cu(en)(HO)][Tb(PWO)(CHCOO)(HO)]}·15HO ( 2) (en = 1,2-ethylenediamine) have been prepared under hydrothermal conditions and characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analyses and X-ray single-crystal diffraction. X-ray structural analyses reveal that 1 exhibits the 1D zigzag chain architecture formed by dimeric oxalate-bridging {[Cu(en)][Ce(GeWO)(HO)](CO)} units and [Cu(en)] linkers whereas 2 displays a typical hybrid acetate-bridging dimeric structure [(α-PWO)Tb(HO)(η,μ-1,1)-CHCOO] modified by [Cu(en)(HO)] fragments. Notably, both contain 2:2-type carboxylate-bridging monolanthanide-substituted Keggin-type dimeric moieties and two types of organic ligands. 1 represents the rare 1D Cu-Ln heterometallic germanotungstate containing mixed ligands of en and oxalate whereas 2 represents the rare dimeric organic-inorganic hybrid Keggin-type phosphotungstate containing both Cu-Ln heterometals and mixed ligands of en and acetate. Graphical Abstract: Two new organic-inorganic hybrid copper-lanthanide heterometallic polyoxotungstates containing mixed organic ligands of en and carboxylate were successfully separated under hydrothermal conditions. 1 exhibits the 1D zigzag chain architecture formed by dimeric oxalate-bridging {[Cu(en)][Ce(GeWO)(HO)](CO)} units by [Cu(en)] linkers, whereas 2 displays a typical hybrid acetate-bridging dimeric structure [(α-PWO)Tb(HO)(η,μ-1,1)-CHCOO] modified by [Cu(en)(HO)] fragments.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Prothoracicotropic hormone (PTTH) is one of key players in regulation of insect growth, molting, metamorphosis, diapause, and is expressed specifically in the two pairs of lateral PTTH-producing neurosecretory cells in the brain. Analysis of cis-regulatory elements of the PTTH promoter might elucidate the regulatory mechanism controlling PTTH expression. In this study, the PTTH gene promoter of Bombyx mori (Bom-PTTH) was cloned and sequenced. The cis-regulatory elements in Bom-PTTH gene promoter were predicted using Matinspector software, including myocyte-specific enhancer factor 2, pre-B-cell leukemia homeobox 1, TATA box, etc. Transient transfection assays using a series of fragments linked to the luciferase reporter gene indicated that the fragment spanning −110 to +33 bp of the Bom-PTTH promoter showed high ability to support reporter gene expression, but the region of +34 to +192 bp and −512 to −111 bp repressed the promoter activity in the BmN and Bm5 cell lines. Electrophoretic mobility shift assays demonstrated that the nuclear protein could specifically bind to the region spanning −124 to −6 bp of the Bom-PTTH promoter. Furthermore, we observed that the nuclear protein could specifically bind to the −59 to −30 bp region of the Bom-PTTH promoter. A classical TATA box, TATATAA, localized at positions −47 to −41 bp, which is a potential site for interaction with TATA box binding protein (TBP). Mutation of this TATA box resulted in no distinct binding band. Taken together, TATA box was involved in regulation of PTTH gene expression in B. mori. [ABSTRACT FROM AUTHOR]

Abstract  Using long-polymerase chain reaction (Long-PCR) method, we determined the complete nucleotide sequence of the mitochondrial genome (mitogenome) of Phthonandria atrilineata. The complete mtDNA from P. atrilineata was 15,499 base pairs in length and contained 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and a control region. The P. atrilineata genes were in the same order and orientation as the completely sequenced mitogenomes of other lepidopteran species. The nucleotide composition of P. atrilineata mitogenome was biased toward A + T nucleotides (81.02%), and the 13 PCGs show different A + T contents that range from 73.25% (cox1) to 92.12% (atp8). Phthonandria had the canonical set of 22 tRNA genes, that fold in the typical cloverleaf structure described for metazoan mt tRNAs, with the unique exception of trnS(AGN). The phylogenetic relationships were reconstructed with the concatenated sequences of the 13 PCGs of the mitochondrial genome, which confirmed that P. atrilineata is most closely related to the superfamily Bombycoidea. [ABSTRACT FROM AUTHOR]

Abstract  Cytokinin oxidase plays an important role in the cytokinins regulatory processes. A putative cytokinin oxidase gene, D endrobium h uoshanense cytokinin oxidase (DhCKX), was cloned by reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) of total RNA isolated from shoot apices of D. huoshanense plantlets in the presence of 20 μmol l−1 6-benzylamino-purine (BAP). The full-length cDNA contains an open reading frame (ORF) encoding a putative protein of 537 amino acids with high homology to known CKX genes and with a predicted molecular mass of 60.383 kDa. Compared with the CKX sequences from other species, the DhCKX shows high identity with Dendrobium hybrid “Sonia”, 92.2% in nucleotide sequence and 89.9% in amino acid sequence, respectively. Based on the alignment of amino acid sequences, the phylogenetic tree of 15 CKX genes is constructed. Semi-quantitative RT-PCR analysis showed that the expression of the DhCKX gene was induced in roots, shoot apices and leaves, but not in stems, after treatment with 20 μmol l−1 BAP. The DhCKX gene showed maximum expression in shoot apices at day 12 during continuous treatment with 20 μmol l−1 BAP. Furthermore, CKX activity appears to play an important role in controlling the cytokinin levels and growth during shoot morphogenesis in D. huoshanense. [ABSTRACT FROM AUTHOR]

Intracranial aneurysms are pathological dilatations which endanger people’s health. Hemodynamics is thought to be an important factor in the pathogenesis and treatment of aneurysms. To date, the bulk of investigations into hemodynamics have been conducted by making use of mathematically idealized models for rigid aneurysms and associated arteries. However the walls of aneurysms and associated arteries are elastic in vivo. This study shows the differences of the simulation between elastic and rigid wall models. The numerical simulation of elastic aneurysm model is made from a representative Digital Subtraction Angiography (DSA) image and calculated with CFD software to get the wall deformation and the velocity field. Then the results are analyzed. By comparing the simulation results of the two models from their velocity vectors and shear stress distribution, many differences can be noted. The main difference exists in the distribution of velocity magnitude at some sections, with one outlet having obviously off-center distribution for the elastic wall model. The currents of the distribution of wall shear stress along the wall of aneurysm simulated in rigid and elastic wall models were similar. But there were apparent differences between the two models on the values of wall shear stress especially at the neck of aneurysm. The off-center distribution of velocity magnitude affects the distribution of wall shear stress and the exchange of substance through the wall. The analysis demonstrated clearly that the results of 2-D elastic numerical simulation were in good agreement with the clinical and pathological practice. The results of this study play an important role in the formation, growth, rupture and prognosis of an aneurysm on clinic application. [ABSTRACT FROM AUTHOR]