bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential Roles of Arabidopsis Heterotrimeric G-Protein Subunits in Modulating Cell Division in Roots
Authors: Chen Jin-Gui , Gao Yajun , Jones Alan M.
Published: May 2006

Signaling through heterotrimeric G proteins is conserved in diverse eukaryotes. Compared to vertebrates, the simpler repertoire of G-protein complex and accessory components in Arabidopsis (Arabidopsis thaliana) offers a unique advantage over all other multicellular, genetic-model systems for dissecting the mechanism of G-protein signal transduction. One of several biological processes that the G-protein complex regulates in Arabidopsis is cell division. We determined cell production rate in the primary root and the formation of lateral roots in Arabidopsis to define individually the types of modulatory roles of the respective G-protein α- and β-subunits, as well as the heterotrimer in cell division. The growth rate of the root is in part a consequence of cell cycle maintenance in the root apical meristem (RAM), while lateral root production requires meristem formation by founder pericycle cells. Thus, a comparison of these two parameters in various genetic backgrounds enabled dissection of the role of the G-protein subunits in modulation of cell division, both in maintenance and initiation. Cell production rates were determined for the RAM and lateral root formation in gpa1 (Arabidopsis G-protein α-subunit) and agb1 (Arabidopsis G-protein β-subunit) single and double mutants, and in transgenic lines overexpressing GPA1 or AGB1 in agb1 or gpa1 mutant backgrounds, respectively. We found in the RAM that the heterotrimeric complex acts as an attenuator of cell proliferation, whereas the GTP-bound form of the Gα-subunit's role is a positive modulator. In contrast, for the formation of lateral roots, the Gβγ-dimer acts largely independently of the Gα-subunit to attenuate cell division. These results suggest that Arabidopsis heterotrimeric G-protein subunits have differential and opposing roles in the modulation of cell division in roots.
PHO2, MicroRNA399, and PHR1 Define a Phosphate-Signaling Pathway in Plants
Authors: Bari Rajendra , Datt Pant Bikram , Stitt Mark , Scheible Wolf-Rüdiger
Published: May 2006

Inorganic phosphate (Pi)-signaling pathways in plants are still largely unknown. The Arabidopsis (Arabidopsis thaliana) pho2 mutant overaccumulates Pi in leaves in Pi-replete conditions. Micrografting revealed that a pho2 root genotype is sufficient to yield leaf Pi accumulation. In pho2 mutants, Pi does not repress a set of Pi starvation-induced genes, including AtIPS1, AT4, and Pi transporters Pht1;8 and Pht1;9. Map-based cloning identified PHO2 as At2g33770, an unusual E2 conjugase gene. It was recently shown that Pi deprivation induces mature microRNA (miRNA [miR399]) and that overexpression of miR399 in Pi-replete conditions represses E2 conjugase expression and leads to high leaf Pi concentrations, thus phenocopying pho2. We show here that miR399 primary transcripts are also strongly induced by low Pi and rapidly repressed after addition of Pi. PHO2 transcripts change reciprocally to miR399 transcripts in Pi-deprived plants and in miR399 overexpressers. However, responses after Pi readdition and in β-glucuronidase reporter lines suggest that PHO2 expression is also regulated by Pi in a manner unrelated to miR399-mediated transcript cleavage. Expression of miR399 was strongly reduced in Pi-deprived Arabidopsis phr1 mutants, and a subset of Pi-responsive genes repressed in Pi-deprived phr1 mutants was up-regulated in Pi-replete pho2 mutants. This places miR399 and PHO2 in a branch of the Pi-signaling network downstream of PHR1. Finally, putative PHO2 orthologs containing five miR399-binding sites in their 5′-untranslated regions were identified in other higher plants, and Pi-dependent miR399 expression was demonstrated in rice (Oryza sativa), suggesting a conserved regulatory mechanism.
The Gene Controlling the Quantitative Trait LocusEPITHIOSPECIFIER MODIFIER1Alters Glucosinolate Hydrolysis and Insect Resistance inArabidopsis
Authors: Zhang Zhiyong , Ober James A. , Kliebenstein Daniel J.
Published: May 2006

Glucosinolates are sulfur-rich plant secondary metabolites whose breakdown products have a wide range of biological activities in plant–herbivore and plant–pathogen interactions and anticarcinogenic properties. In Arabidopsis thaliana, hydrolysis by the enzyme, myrosinase, produces bioactive nitriles, epithionitriles, or isothiocyanates depending upon the plant's genotype and the glucosinolate's structure. A major determinant of this structural specificity is the epithiospecifier locus (ESP), whose protein causes the formation of epithionitriles and nitriles. A quantitative trait locus (QTL) on chromosome 3 epistatically affects nitrile formation in combination with ESP; this QTL has been termed EPITHIOSPECIFIER MODIFIER1 (ESM1). We identified a myrosinase-associated protein as the ESM1 QTL in Arabidopsis using map-based cloning with recombinant inbred lines, natural variation transcriptomic analysis, and metabolic profiling. In planta and in vitro analyses with natural ESM1 alleles, ESM1 knockouts, and overexpression lines show that ESM1 represses nitrile formation and favors isothiocyanate production. The glucosinolate hydrolysis profile change influenced by ESM1 is associated with the ability to deter herbivory by Trichoplusia ni. This gene could provide unique approaches toward improving human nutrition.
(E)-5-[(3-Chlorophenyl)diazenyl]-2-hydroxy-3-methoxybenzaldehyde
Authors: Karadayı Nevzat , Albayrak Çiğdem , Odabaşoğlu Mustafa , Büyükgüngör Orhan
Published: May 2006

The title compound, C14H11ClN2O3, contains an azo group (–N=N–), and the configuration around the –N=N– double bond is trans. There are intramolecular O—H...O and intermolecular C—H...O hydrogen bonds, and the crystal packing is stabilized by C—H...π and π–π stacking interactions, forming a two-dimensional network.
Methyl 2-{[3-(3-methoxyphenyl)-1,2,4-oxadiazol-5-yl]methoxy}phenylacetate
Authors: Wang Hai-Bo , Liu Zhi-Qian , Yan Xiao-Chen
Published: May 2006

The title compound, C19H18N2O5, was synthesized by the reaction of methyl (2-hydroxyphenyl)acetate and 5-chloromethyl-3-(3-methoxyphenyl)-1,2,4-oxadiazole. The plane of the oxadiazole ring forms a small dihedral angle of 15.2 (2)° with the plane of the benzene ring directly bonded to it, whereas the second benzene ring is approximately orthogonal to the oxadiazole plane, the dihedral angle being 79.1 (2)°.
Tris(4-acetylphenyl)amine
Authors: Cui Chun Mei , Zhou Hong Ping , Zhu Chen Hao , Wu Jie Ying
Published: May 2006

The crystal structure of the title compound, C24H21NO3, is stabilized by weak C—H...π interactions.
8-Oxocanadine
Authors: Wang Xiao-Ling
Published: May 2006

The title compound, C20H19NO5, a protoberberine-type alkaloid, was isolated from the roots of the plant Sinomenium acutum. The piperidine ring adopts a screw-boat conformation and the pyridinone ring is in an envelope conformation.
3,4-Methylenedioxybenzoic acid
Authors: Li Jiang-Tao , Wang Yong-Li , Zhou Li-Na , Wang Jing-Kang
Published: May 2006

The crystal structure of the title compound, C8H6O4, consists of layers of characteristic dimers formed by intermolecular O—H...O hydrogen bonds.
2-[4,5-Bis(n-pentylsulfanyl)-1,3-dithiol-2-ylidene]-1,3-dithiolo[4,5-c]pyrrole
Authors: Nielsen Kent A. , Bond Andrew D. , Jeppesen Jan O.
Published: May 2006

The crystal structure of the title compound, C18H25NS6, at 180 K contains molecules distorted significantly from planarity. The structure is non-centrosymmetric.
1,2,4,5-Tetrafluoro-3,6-bis(nitromethyl)benzene
Authors: Perašínová Lucia , Svoboda Ingrid , Végh Daniel , Solčan Tomaš , Kožíšek Jozef
Published: May 2006

The title compound, C8H4F4N2O4, crystallizes on a site of crystallographic inversion symmetry.
μ-Chloro-μ-diphenylphosphido-μ-hydrido-bis[(η6-hexamethylbenzene)ruthenium(II)] tetrafluoroborate
Authors: Tschan Mathieu Jean-Luc , Therrien Bruno , Süss-Fink Georg
Published: May 2006

The new triple-bridged dinuclear cation [(η6-C6Me6)2Ru2(μ2-Cl)(μ2-H)(μ2-PPh2)]+ was formed in chloroform from the precursor [(η6-C6Me6)2Ru2(μ2-H)2(μ2-PPh2)]+ and characterized as the tetrafluoroborate salt [(η6-C12H18)2Ru2(μ2-Cl)(μ2-H){μ2-P(C6H5)2}]BF4. The single-crystal X-ray structure analysis confirms the formation of the meso form. Despite the presence of two stereogenic centres, the complex is not chiral.
Diaquasulfato(2,4,6-tri-2-pyridyl-1,3,5-triazine)nickel(II) dihydrate
Authors: Díaz de Vivar Maria Enriqueta , Baggio Sergio , Baggio Ricardo
Published: May 2006

The title compound, [Ni(SO4)(C18H12N6)(H2O)2]·2H2O, is isostructural with the zinc and cobalt analogues already reported in the literature. The compound is monomeric, with an octahedral Ni centre coordinated by a tridentate 2,4,6-tri-2-pyridyl-1,3,5-triazine ligand, two water molecules and a monodentate sulfate ligand. The presence of two additional water molecules of crystallization leads to a total of eight hydrogen-bond donors, from which a very complex hydrogen-bonding scheme is built up.
1,5-Dimethy-4-[(2-nitrobenzylidene)amino]-2-phenyl-1H-pyrazol-3(4H)-one
Authors: Li Zong-Xiao , Zhang Xin-Li
Published: May 2006

The title compound, C18H16N4O3, has been synthesized by the reaction of 2-nitrobenzaldehyde and 4-aminoantipyrine. The molecule adopts an E configuration about the central C=N double bond.
Dimethyl 3t,4t-dicarboxytetrahydrofuran-2r,5c-dicarboxylate
Authors: Villiers Claude , Thuéry Pierre , Ephritikhine Michel
Published: May 2006

Esterification of tetrahydrofuran-2r,3t,4t,5c-tetracarboxylic acid gave selectively the title compound, C10H12O9, in which the two more acidic carboxylic acid groups, in positions 2 and 5, have been esterified. The five-membered ring is in a twist conformation. Hydrogen bonding results in double chains, or ribbons, running along the c axis.
3-Benzoyl-4-hydroxy-2,4,6-triphenylcyclohexane-1,1-dicarbonitrile
Authors: Rong Liang-Ce , Li Xiao-Yue , Yang Fang , Wang Hai-Ying , Shi Da-Qing
Published: May 2006

The title compound, C33H26N2O2, was synthesized by the reaction of chalcone with malononitrile under solvent-free conditions at 353 K. X-ray analysis reveals that the cyclohexane ring adopts a chair conformation.
2′-[2-(4-Fluorophenyl)chroman-4-ylidene]isonicotinohydrazide
Authors: Nie Aihua , Ghosh Sutapa , Huang Ziwei
Published: May 2006

In the title compound, C21H16FN3O2, the pyridine ring is nearly coplanar with the plane of the fused bicyclic ring system [dihedral angle = 4.1 (2)°], while the 4-fluorophenyl ring forms a dihedral angle of 67.7 (3)° with the fused bicyclic ring system.
N-(4-Bromobenzyl)-4-cyanopyridinium bis(2-thioxo-1,3-dithiole-4,5-dithiolato)nickelate(III) acetone solvate
Authors: Zang Shuang-Quan , Su Yang , Tao Ruo-Jie
Published: May 2006

The title compound, (C13H10BrN2)[Ni(C3S5)2]·C3H6O, is a new ionic complex in which the NiIII atom exhibits a square-planar coordination involving four S atoms from two 2-thioxo-1,3-dithiole-4,5-dithiolate (dmit) ligands. In the crystal structure, weak S...S and hydrogen-bonding interactions form a three-dimensional supramolecular network.
16β-Bromo-17-hydroxypregn-4-ene-3,11,20-trione chloroform solvate
Authors: Nie Qiang , Wang Jing-Kang , Zhou Lina
Published: May 2006

The title compound (systematic name: 17-acetyl-16-bromo-17-hydroxy-10,13-dimethyl-1,6,7,8,9,10,12,13,14, 15,16,17-dodecahydro-2H-cyclopenta[a]phenanthrene-3,11-dione chloroform solvate), C21H27BrO4·CHCl3, is an important intermediate in the synthesis of hormone pharmaceuticals. The asymmetric unit consists of one steroid and one chloroform molecule. The crystal structure is predominantly stabilized by strong intermolecular O—H...O hydrogen bonds.
9-[4-(6-Bromo-4-phenylnaphthalen-2-yl)phenyl]-9H-carbazole
Authors: Zhang Shou-Cai , Che Guang-Bo , Liu Bo
Published: May 2006

The title compound, C34H22BrN, was synthesized by N-alkylation of 7-bromo-3-(4-bromophenyl)-1-phenylnaphthalene with 9H-carbazole. The carbazole ring system is essentially planar and makes a dihedral angle of 48.63 (9)° with the plane of the adjacent benzene ring.
2,2′-[(Ethylenedioxy)bis(ethyleneoxy)]bis[N-(2-pyridyl)benzamide]
Authors: Wang Wen-Hua , You Zhong-Lu , Liu Wei-Sheng , Wang Da-Qi
Published: May 2006

In the title compound, C30H30N4O6, the dihedral angle between the two N-(2-pyridyl)benzamide units is 71.11 (5)°. The molecule exhibits an S-shaped structure which is stabilized by N—H...O hydrogen bonds.
Methyl 3-[4,6-bis(diphenylphosphino)phenoxazin-10-yl]propionate
Authors: Ricken Stefan , Osinski Piotr W. , Schürmann Markus , Preut Hans , Eilbracht Peter
Published: May 2006

In the title compound, C40H33NO3P2, used as a nixantphos-type ligand in homogeneous catalysis, the central phenoxazine ring system is nearly planar. The most important feature of the molecule is the intramolecular P...P distance of 4.2346 (13) Å. The angles involving the P atoms are in the range 100.90 (13)–103.40 (16)°.
Potassium 2-methyl-5-nitrobenzenesulfonate
Authors: Xie Yong-Rong , Lui Gui-Rong , Yuan Xiao-Yong
Published: May 2006

The title compound, K+·C7H6NO5S−, consists of a two-dimensional framework of K+ ions coordinated to 2-methyl-5-nitrobenzenesulfonate anions. The K+ ion is typically eight-coordinate, surrounded by eight O atoms from six 2-methyl-5-nitrobenzenesulfonate anions.
Diaquabis(1,10-phenanthroline-κ2
N,N′)manganese(II) pentafluorooxoniobate(V)
Authors: Zhu Gang , Tang Zong-Xun
Published: May 2006

In the title compound, [Mn(C12H8N2)2(H2O)2][NbOF5], each of the MnII and NbV atoms has a distorted octahedral coordination. In the [NbOF5]2− anion, a characteristic short terminal Nb=O bond and a longer Nb—F bond are observed, which result in the out-of-center distortion of the octahedron, a manifestation of the second-order Jahn–Teller effect.
(η3-Allyl)bromo(η5-cyclopentadienyl)(phenylaminodiphenylphosphine-κP)ruthenium(IV) hexafluorophosphate
Authors: Pavlik Sonja , Kirchner Karl , Mereiter Kurt
Published: May 2006

The title compound, [RuBr(η5-C5H5)(η3-C3H5)(C18H16NP)]PF6, contains a half-sandwich cyclopentadienylruthenium(IV) complex with a three-legged piano-stool structure and an intramolecular N—H...Br hydrogen bond.
2-(1′,5′,5-Trimethyl-3,3′-bi-1H-pyrazol-1-yl)ethanol
Authors: Attayibat Ahmed , Radi Smaail , Ramdani Abdelkrim , Eddike Driss , Tillard Monique , Belin Claude
Published: May 2006

In the crystal structure of the title compound, C11H16N4O, the two pyrazole rings are coplanar, as indicated by both the dihedral angle of 0.8 (1)° between their mean planes and the N—C—C—N torsion angle of 179.81 (13)°.
A photodimer of a 4-phenyl-4H-pyran
Authors: Yan Hong , Wang Hui-Qin , Ni Cheng-Liang , Song Xiu-Qing
Published: May 2006

A new cage photodimer, tetraethyl 2,4,8,10-tetramethyl-6,12-diphenyl-3,9-dioxapentacyclo[6.4.0.02,7.04,11.05,10]dodecane-1,5,7,11-tetracarboxylate, C38H44O10, was prepared through [2+2]-photocycloaddition of diethyl 2,6-dimethyl-4-phenyl-4H-pyran-3,5-dicarboxylate in the solid state. The molecular structure was elucidated by X-ray diffraction analysis, 1H NMR, IR and mass spectroscopy, and elemental analysis. The molecule possesses a crystallographically imposed centre of symmetry. The crystal structure is stabilized by weak C—H...O hydrogen-bond interactions.
Bis(piperidinium) chloranilate
Authors: Refat Moamen S. , Ahmed Hamdy Al-Didamony , El-Zayat Lamia A. , Fukunaga Takeo , Ishida Hiroyuki
Published: May 2006

In the title crystal structure, 2C5H12N+·C6Cl2O4
2−, chloranilate and piperidinium ions are connected by bifurcated N—H...O hydrogen bonds, giving a centrosymmetric chloranirate–piperidinium 1:2 unit. The 1:2 units are connected to each other by N—H...O hydrogen bonds, forming a molecular ladder. There is a centre of symmetry at the centre of the anion ring.
1-Chloro-4-octyloxy-10-thiaanthracen-9-one
Authors: Ji Xiao-Juan , Liu Xuan-Gan , Rao Guo-Wu
Published: May 2006

In the title compound, C21H23ClO2S, the three fused rings are roughly coplanar. The two benzene rings are twisted by a dihedral angle of 7.15 (15)°.
Aquadichloro(2,9-dimethyl-1,10-phenanthroline-κ2
N,N′)nickel(II)
Authors: Ding Cai-Feng , Miao Yan-Fang , Tian Bing-Qing , Li Xue-Mei , Zhang Shu-Sheng
Published: May 2006

In the title compound, [NiCl2(C14H12N2)(H2O)], there are two molecules in the asymmetric unit. Each Ni atom is five-coordinate in a geometry between trigonal–bipyramidal and tetragonal–pyrimidal. Molecules are linked into a three-dimensional framework by O—H...Cl and C—H...Cl hydrogen bonds. The packing is further stabilized by π–π interactions between the phenanthroline ring systems.
4-Difluoromethyl-1-(4-methylphenyl)-1H-1,2,3-triazole
Authors: Costa Marilia S. , Boechat Nubia , Ferreira Vitor F. , Wardell Solange M. S. V. , Skakle Janet M. S.
Published: May 2006

In the crystal structure of the title compound, C10H9F2N3, weak hydrogen bonding involving the triazole and difluoromethyl groups leads to the formation of chains along [010]. The benzene and triazole rings are essentially coplanar, with an angle of 0.34 (17)° between the planes defined by the two rings.
1-Acetyl-3-ethyl-r-2,c-6-di-2-furylpiperidin-4-one
Authors: Balamurugan S. , Thiruvalluvar A. , Manimekalai A. , Selvaraju K. , Maruthavanan T.
Published: May 2006

In the title molecule, C17H19NO, the piperidine ring adopts a chair conformation. The acetyl group in the 1-position and ethyl group in the 3-position each have an equatorial orientation. The furyl rings at positions 2 and 6 have axial orientations.
3-[5-(2,4-Dichlorophenyl)-1,3,4-thiadiazol-2-yl]-2-phenylthiazolidin-4-one
Authors: Wu Feng , Wan Rong , Fan Hong-Jing , Zhang Rong , Wang Jin-Tang
Published: May 2006

The title compound, C17H11Cl2N3OS2, was synthesized by the reaction of benzylidene[5-(2,4-dichlorophenyl)-1,3,4-thiadiazol-2-yl]amine and mercaptoacetic acid. In the crystal structure, there are C—H...O hydrogen bonds, resulting in a three-dimensional network. There is also a short intermolecular N...Cl interaction.
A 2:1 cocrystal of 2,3-bis(4-bromophenyl)quinoxaline and 1,2-bis(4-bromophenyl)ethane-1,2-diol
Authors: Rong Liang-Ce , Li Xiao-Yue , Yao Chang-Sheng , Wang Hai-Ying , Shi Da-Qing
Published: May 2006

The title compound, C20H12Br2N2·0.5C14H12Br2O2, was synthesized by the one-pot reaction of benzofurazan oxide and 1,2-bis(4-bromophenyl)ethane-1,2-dione induced by a low-valent titanium reagent. X-ray analysis reveals that the 1,2-bis(4-bromophenyl)ethane-1,2-diol molecule is located on an inversion centre. The molecules are linked via O—H...N hydrogen bonds and C—H...π interactions.
3-(1,3-Benzothiazol-2-yl)-2-naphthol
Authors: Huang Zhi-Qiang , Du Zhi-Qiang , Du Guan-Sheng , Yan Jun
Published: May 2006

The molecule of the title compound, C17H11NOS, is planar, the dihedral angle between the benzothiazole and 2-naphthol systems being 3.44 (6)°. The face-to-face separation of 3.48 (2) Å indicates π–π stacking between parallel benzothiazole systems.
Benzylideneacetophenone 2,4-dinitrophenylhydrazone
Authors: Qian Heng-Yu , Liu Cheng , Yin Zhi-Gang , Ng Seik Weng
Published: May 2006

The title Schiff base compound, C21H16N4O4, features a crystallographically imposed planar —NH—N= linkage of an E configuration.
(1R,2R)-(+)-1-(2-Hydroxybenzylideneamino)-2-(p-tolylsulfonylamino)cyclohexane
Authors: Yang Hong-Wei , Li Yi-Zhi , Pan Xu , Sun Jiang-Tao , Zhu Cheng-Jian
Published: May 2006

The title compound, C20H24N2O3S, was synthesized by a two-step reaction. In the crystal structure, chains of molecules are formed through N—H...O hydrogen bonds and weak C—H...O interactions, and these chains are further linked together through weak C—H...O interactions to form a two-dimensional network structure.
[Bis(trimethylsilyl)methyl]chloro(phenyl)phosphine
Authors: Xi Fang , Chen Xia , Guo Jian-Ping , Liu Dian-Sheng
Published: May 2006

The title compound, C13H24ClPSi2, was synthesized via the reaction of bis(trimethylsily)methyllithium and dichlorophenylphosphine. The coordination geometry around the P atom is distorted tetrahedral.
Diethyl naphthalene-1,8-dicarboxylate
Authors: Jing Lin-Hai , Qin Da-Bin , Gu Shao-Jin , Zhang Huan-Xia , Mao Zhi-Hua
Published: May 2006

The title compound, C16H16O4, crystallizes with two molecules in the asymmetric unit. The two molecules differ in the orientations of the ethyl groups. The crystal packing is stabilized by C—H...O hydrogen bonds.
Diaquabis(pyridine-2,3-dicarboxylato)copper(II)
Authors: Xiang Jiang-Feng , Li Ming , Wu Si-Min , Yuan Liang-Jie , Sun Ju-Tang
Published: May 2006

The centrosymmetric title copper(II) complex, [Cu(C7H4NO4)2(H2O)2], was synthesized via the hydrothermal method at a mild temperature (353 K). The CuII ion has a distorted octahedral coordination environment, with two N and two O atoms from the pyridine-2,3-dicarboxylate ligands in a common plane and with two water molecules in axial positions. Hydrogen bonds play an important role in the formation of the three-dimensional structure.
2,3,2′,3′-Tetramethylbiphenyl
Authors: Zheng Wei , Zhu Hong-Jun , Qian Yi , Wu Yi-Zu
Published: May 2006

The title compound, C16H18, was synthesized by a palladium-catalyzed boronic acid cross-coupling reaction. A crystallographic twofold axis passes through the mid-point of the C—C bond connecting the two rings. In the crystal structure, two fairly close C—H...π(arene) contacts appear to be the only significant intermolecular interactions.
Bis{2-[2-(diethylamino)ethyliminomethyl]-4-nitrophenolato}dimethanolzinc(II) dinitrate
Authors: Qiu Xiao-Yang
Published: May 2006

The title compound, [Zn(C13H19N3O3)2(CH4O)2](NO3)2, is isostructural with the nickel complex reported previously [Chen (2006). Acta Cryst. E62, m204–m206]. The Zn atom lies on an inversion centre and is coordinated octahedrally by N and O atoms of two Schiff base ligands and two MeOH molecules in a trans orientation. In the crystal structure, molecules are linked through O—H...N, O—H...O, N—H...N and N—H...O intermolecular hydrogen bonds, forming chains running along the b axis.
12-(4-Bromophenyl)-9,9-dimethyl-1,2,3,4,9,10-hexahydrobenz[a]acridin-11-one
Authors: Jia Run-Hong , Zhang Qian-Shang , Tu Shu-Jiang , Zhang Yan
Published: May 2006

The title compound, C25H22BrNO, has been synthesized by the reaction of 4-bromobenzaldehyde, 3,3-dimethylcyclopentane-1,3-dione with 2-naphthylamine in ethanol. In the crystal structure, the molecules are connected by N—H...O hydrogen bonds, forming chains along the a axis.
5-(4-Fluorobenzylamino)-3,6-diphenyl-2-thioxo-2,3-dihydro-1,3-thiazolo[4,5-d]pyrimidin-7(6H)-one
Authors: Zhang Qian , Jiao Yuan-Hong
Published: May 2006

In the title compound, C24H17FN4OS2, the three benzene rings are twisted with respect to the fused heterocyclic ring system, with dihedral angles of 76.2 (2), 90.2 (2) and 75.8 (2)°. The crystal packing is influenced by C—H...O, N—H...O and C—H...S hydrogen bonds.
Bis(2-methyl-1H-imidazole)silver(I) nitrate methanol solvate
Authors: Liu Jin , Su Xiao-Yu , Wang Wen-Hai , Mao Zhi-Hua , Xie Ru-Gang
Published: May 2006

The title complex, [Ag(C4H6N2)2]NO3·CH3OH, features a mononuclear cation in which the AgI atom is coordinated in a linear fashion by two N atoms derived from the 2-methylimidazole ligands. The cations, anions and methanol molecules are linked by hydrogen bonds into a chain structure.
3,8-Di-tert-butyl-2,2,9,9-tetramethyldeca-3,7-diene
Authors: Hänel Ralf , Hopf Henning , Jones Peter G.
Published: May 2006

The title compound, C22H42, displays crystallographic inversion symmetry. The conformation of the central chain is defined by the torsion angle C=C—C—C of 124.3 (3)°. The C=C—C angle in the chain is 133.2 (2)°. The central C—C bond is short at 1.516 (4) Å.
cis-[Bis(diphenylphosphino)ethane-κ2
P,P′]dichlororuthenium(II) dichloromethane disolvate
Authors: Russo Luca , Figueira João , Rodrigues João , Rissanen Kari
Published: May 2006

The title compound, cis-[RuCl2(C26H24P2)2]·2CH2Cl2, was obtained as an unexpected product from our attempts to prepare new ruthenium molecular wires using organic bridging ligands. Three solvates and a solvent-free structure of the isomeric complex with the chloride anions in a trans geometry have already been reported, while the cis isomer has been described only in solution studies prior to this work.
1D-1,2,5,6-Tetra-O-methyl-3,4-di-O-phosphinoyl-chiro-inositol 2.5-hydrate
Authors: Gainsford Graeme J. , Lensink Cornelis , Falshaw Andrew
Published: May 2006

In the title compound, C34H38O8P2·2.5H2O, intermolecular interactions consist of strong O—H(water)...O hydrogen bonds, as well as C—H...O interactions.
Silicon Oxycarbide Glasses: Part 1—Thermochemical Stability
Authors: Latournerie Jérôme , Dempsey Phillip , Hourlier‐Bahloul Djamila , Bonnet Jean‐Pierre
Published: May 2006

Silicon oxycarbide glasses (Si/C/O) of various compositions have been obtained after pyrolysis of polysiloxane gels produced by the sol–gel method. Four gels were synthesized from various structures of silicon precursors: MTES issued from methyltriethoxysilane CH3Si(–OEt)3, VTES from vinyltriethoxysilane CH2=CH–Si(–OEt)3, PTES from phenyltriethoxysilane C6H5–Si(–OEt)3 and DHTH 1/9 for that issued from the 1/9 molar ratio of methyldiethoxysilane DH (CH3)HSi–(OEt)2 and TH triethoxysilane HSi(–OEt)3. The resulting materials at 1000°C can be described as an oxycarbide phase with the presence of either an excess of carbon or silicon depending on the starting structure of the precursor used to prepare the gels. By thermogravimetric analysis (TGA) coupled with mass spectrometry (MS), we followed the thermal behavior of each compound from 1000° to 1500°C. Based on these results and chemical analysis data, we have established the main reactions that occur during the decomposition of the oxycarbide glasses. At low temperature (T<1400°C), the dominant mechanism for carbon‐rich materials first involves a solid‐state reaction of SiO2 and C leading to SiC formation and removal of CO. That reaction proceeds at high temperature (above 1400°C), as long as the amount of carbon in the material is high enough (PTES). When the system is depleted of its free carbon (VTES, MTES), however, another reaction can also proceed parallel to the former one, where SiO2 and SiC react leading to a loss of SiO and CO. The combination of an excess of silicon and a dense state of the material improves the thermo‐chemical stability of the silicon oxycarbide phase present in the DHTH 1/9 glass. By placing the chemical compositions in the ternary Si–C–O diagram, we could then determine the evolution at high temperature of any system of mixed Si/Cx/Oy phases.
Interfacial Peeling Moments and Shear Forces at Free Edges of Multilayers Subjected to Thermal Stresses
Authors: Hsueh C. H. , Luttrell C. R. , Lee S. , Wu T. C. , Lin H. Y.
Published: May 2006

Stresses normal to interfaces, i.e., interfacial peeling stresses and interfacial shear stresses, exist locally at edges of multilayers because of both the thermal mismatch between layers and the free‐edge effect. These peeling and shear stresses can result in modes I and II edge delamination, respectively. However, because of the complexity of the problem, exact closed‐form solutions for these stresses are very difficult if not impossible to derive even for bilayered systems. Hence, instead of the detailed stress field at edges, both the interfacial peeling moment resulting from the localized peeling stresses and the interfacial shear force resulting from the localized shear stresses are analyzed here. Exact closed‐form solutions for the peeling moment and the shear force at each interface in elastic multilayered systems are derived. To illustrate the application of present closed‐form solutions, specific results are calculated for five‐layered thermal barrier coating systems, and a finite‐element analysis is also performed to confirm the analytical results.
A “field change” of inhibited apoptosis occurs in colorectal mucosa adjacent to colorectal adenocarcinoma
Authors: Badvie S , Hanna-Morris A , Andreyev H J N , Cohen P , Saini S , Allen-Mersh T G
Published: May 2006

Background:Colorectal cancer is associated with a “field change” of increased proliferation throughout the colonic and rectal mucosa. Both proliferation and apoptosis are disrupted during carcinogenesis. Whether altered apoptosis contributes to this field change of microscopic abnormality is, however, unclear. Bcl-xL is an anti-apoptotic protein that inhibits apoptosis by preventing release of cytochromec, a recognised pathway to cell death.

Aim:To determine whether Bcl-xL inhibition of apoptosis is increased in colorectal mucosa adjacent to colorectal adenocarcinoma over that in normal non-neoplastic colorectal mucosa.

Patients:Patients undergoing surgical resection for neoplastic (adenocarcinoma) or non-neoplastic disease of the colorectum (rectal prolapse, diverticular disease or volvulus).

Methods:Formalin-fixed, paraffin-wax-embedded surgical colorectal resection specimens were immunostained for Bcl-xL protein. Labelling indices were determined by counting the proportion of positively stained cells in mucosal crypts.

Results:85 patients were studied. Bcl-xL immunostaining was most marked in the upper third of mucosal crypts. It occurred in a minority of samples from non-neoplastic colorectal mucosa, but was seen in most mucosal samples adjacent to colorectal adenocarcinoma. Significant increases (p<0.001) were observed in Bcl-xL labelling indices in the mucosa at 1 cm (n = 46, median labelling index 31.8%, interquartile range 8.3–43.9%) and at 10 cm (n = 52, median labelling index 22.0%, interquartile range 0.0–36.3%) from colorectal carcinoma, compared with normal, non-neoplastic colorectal mucosa (n = 22, median labelling index 0.0%, interquartile range 0.0–0.0%).

Conclusions:The findings are consistent with a field change of inhibited apoptosis in mucosa adjacent to colorectal carcinoma.
Scaling of diastolic intraventricular pressure gradients is related to filling time duration
Authors: Popović Zoran B. , Richards Kathryn E. , Greenberg Neil L. , Rovner Aleksandr , Drinko Jeannie , Cheng Yuanna , Penn Marc S. , Fukamachi Kiyotaka , Mal Niladri , Levine Benjamin D. , Garcia Mario J. , Thomas James D.
Published: May 2006

In early diastole, pressure is lower in the apex than in the base of the left ventricle (LV). This early intraventricular pressure difference (IVPD) facilitates LV filling. We assessed how LV diastolic IVPD and intraventricular pressure gradient (IVPG), defined as IVPD divided by length, scale to the heart size and other physiological variables. We studied 10 mice, 10 rats, 5 rabbits, 12 dogs, and 21 humans by echocardiography. Color Doppler M-mode data were postprocessed to reconstruct IVPD and IVPG. Normalized LV filling time was calculated by dividing filling time by RR interval. The relationship between IVPD, IVPG, normalized LV filling time, and LV end-diastolic volume (or mass) as fit to the general scaling equation Y = kMβ, where M is LV heart size parameter, Y is a dependent variable, k is a constant, and β is the power of the scaling exponent. LV mass varied from 0.049 to 194 g, whereas end-diastolic volume varied from 0.011 to 149 ml. The β values relating normalized LV filling time with LV mass and end-diastolic volume were 0.091 (SD 0.011) and 0.083 (SD 0.009), respectively ( P < 0.0001 vs. 0 for both). The β values relating IVPD with LV mass and end-diastolic volume were similarly significant at 0.271 (SD 0.039) and 0.243 (SD 0.0361), respectively ( P < 0.0001 vs. 0 for both). Finally, β values relating IVPG with LV mass and end-diastolic volume were −0.118 (SD 0.013) and −0.104 (SD 0.011), respectively ( P < 0.0001 vs. 0 for both). As a result, there was an inverse relationship between IVPG and normalized LV filling time ( r = −0.65, P < 0.001). We conclude that IVPD decrease, while IVPG increase with decreasing animal size. High IVPG in small mammals may be an adaptive mechanism to short filling times.
Developmental changes in passive stiffness and myofilament Ca2+sensitivity due to titin and troponin-I isoform switching are not critically triggered by birth
Authors: Krüger Martina , Kohl Thomas , Linke Wolfgang A.
Published: May 2006

The giant protein titin, a major contributor to myocardial mechanics, is expressed in two main cardiac isoforms: stiff N2B (3.0 MDa) and more compliant N2BA (>3.2 MDa). Fetal hearts of mice, rats, and pigs express a unique N2BA isoform (∼3.7 MDa) but no N2B. Around birth the fetal N2BA titin is replaced by smaller-size N2BA isoforms and N2B, which predominates in adult hearts, stiffening their sarcomeres. Here we show that perinatal titin-isoform switching and corresponding passive stiffness (STp) changes do not occur in the hearts of guinea pig and sheep. In these species the shift toward “adult” proportions of N2B isoform is almost completed by midgestation. The relative contributions of titin and collagen to STpwere estimated in force measurements on skinned cardiac muscle strips by selective titin proteolysis, leaving the collagen matrix unaffected. Titin-based STpcontributed between 42% and 58% to total STpin late-fetal and adult sheep/guinea pigs and adult rats. However, only ∼20% of total STpwas titin based in late-fetal rat. Titin-borne passive tension and the proportion of titin-based STpgenerally scaled with the N2B isoform percentage. The titin isoform transitions were correlated to a switch in troponin-I (TnI) isoform expression. In rats, fetal slow skeletal TnI (ssTnI) was replaced by adult carciac TnI (cTnI) shortly after birth, thereby reducing the Ca2+sensitivity of force development. In contrast, guinea pig and sheep coexpressed ssTnI and cTnI in fetal hearts, and skinned fibers from guinea pig showed almost no perinatal shift in Ca2+sensitivity. We conclude that TnI-isoform and titin-isoform switching and corresponding functional changes during heart development are not initiated by birth but are genetically programmed, species-specific regulated events.
Cytoskeletal networks and the regulation of cardiac contractility: microtubules, hypertrophy, and cardiac dysfunction
Authors: Cooper George
Published: May 2006

The cytoskeleton as classically defined for eukaryotic cells consists of three systems of protein filaments: the microtubules, the intermediate filaments, and the microfilaments. In mature striated muscle such as the heart of the adult mammal, these three types of cytoskeletal filaments are superimposed spatially on the myofilaments, a specialized system of contractile protein filaments. Each of these systems of protein filaments has the potential to respond in an adaptive or maladaptive manner during load-induced hypertrophic cardiac growth. However, the extent to which such hypertrophy is compensatory is also critically dependent on the type of hemodynamic overload that serves as the hypertrophic stimulus. Thus cardiac hypertrophy is not intrinsically maladaptive; rather, it is the nature of the inducing load rather than hypertrophy itself that is responsible, through effects on structural and/or regulatory proteins, for the frequent deterioration of initially compensatory hypertrophy into the congestive heart failure state. As one example reviewed here of this load specificity of maladaptation, increased microtubule network density is a persistent feature of severely pressure-overloaded, hypertrophied, and failing myocardium that imposes a primarily viscous load on active myofilaments during contraction.
Effects of targeted deletion of A1adenosine receptors on postischemic cardiac function and expression of adenosine receptor subtypes
Authors: Morrison R. Ray , Teng Bunyen , Oldenburg Peter J. , Katwa Laxmansa C. , Schnermann Jurgen B. , Mustafa S. Jamal
Published: May 2006

To examine ischemic tolerance in the absence of A1adenosine receptors (A1ARs), isolated wild-type (WT) and A1AR knockout (A1KO) murine hearts underwent global ischemia-reperfusion, and injury was measured in terms of functional recovery and efflux of lactate dehydrogenase (LDH). Hearts were analyzed by real-time RT-PCR both at baseline and at intervals during ischemia-reperfusion to determine whether compensatory expression of other adenosine receptor subtypes occurs with either A1AR deletion and/or ischemia-reperfusion. A1KO hearts had higher baseline coronary flow (CF) and left ventricular developed pressure (LVDP) than WT hearts, whereas heart rate was unchanged by A1AR deletion. After 20 min of ischemia, CF was attenuated in A1KO compared with WT hearts, and this reduction persisted throughout reperfusion. Final recovery of LVDP was decreased in A1KO hearts (54.4 ± 5.1 vs. WT 81.1 ± 3.4% preischemic baseline) and correlated with higher diastolic pressure during reperfusion. Postischemic efflux of LDH was greater in A1KO compared with WT hearts. Real-time RT-PCR demonstrated the absence of A1AR transcript in A1KO hearts, and the message for A2A, A2B, and A3adenosine receptors was similar in uninstrumented A1KO and WT hearts. Ischemia-reperfusion increased A2BmRNA expression 2.5-fold in both WT and A1KO hearts without changing A1or A3expression. In WT hearts, ischemia transiently doubled A2AmRNA, which returned to preischemic level upon reperfusion, a pattern not observed in A1KO hearts. Together, these data affirm the cardioprotective role of A1ARs and suggest that induced expression of other adenosine receptor subtypes may participate in the response to ischemia-reperfusion in isolated murine hearts.
State Administrative Reorganization
Authors: Mathews John M.
Published: May 2006

Writing in 1919, Mr. W. F. Willoughby declared that “at the present time few reforms of government in the United States are more urgent than that of the reorganization of the administrative services of our state governments, so as to put them upon the integrated or departmental basis.” This need for state administrative reorganization is now generally recognized, not only by political scientists and students of administration, but also by public officials and practical administrators. This is indicated by the large number of governors who, in public messages, have urged upon their legislatures the adoption of measures of administrative reform; by the investigations and reports of efficiency and economy commissions or similar bodies created in many states; and by the laws actually passed providing for administrative reorganization in Illinois, Idaho, Nebraska, Ohio, Washington, Massachusetts, and other states.

A movement of this character naturally follows the line of least resistance, and consequently the changes in administrative organization heretofore made have been through statutory enactment rather than through constitutional revision. Inasmuch as, in most states, a faulty organization of the administration is stereotyped in the constitution, thoroughgoing reorganization by mere statutory enactment is practically impossible. The constitutional difficulties which impede the movement for administrative reorganization should warn us against the insertion in the organic law of detailed administrative provisions.
International Status of the British Dominions
Authors: Allin C. D.
Published: May 2006

The appeal of the British government to the dominions for aid in defending the Dardanelles served to call attention once more to one of the most anomalous features of the constitution of the empire, namely the absence of a definite imperial policy in the matter of war and peace. On this most vital of all questions one would naturally expect to find at least some general understanding between the mother country and the dominions as to their respective rights and obligations. But such is not the case. The principles and practice of the constitution are hopelessly at variance.
The Constitution of Latvia
Authors: Pollock James K.
Published: May 2006

Following the lead of other recently created nations of Europe, Latvia has promulgated a constitution. This new republic came into the world of nations on November 18,1918, when it proclaimed its independence, although its government was not formally recognized by the United States until July 27, 1922. One year previous to this, on September 22, 1921, Latvia became a member of the League of Nations. After the independence of Latvia had been proclaimed, a constituent assembly was convened, and it was this body which drew up the new constitution. It was adopted February 15, 1922, and became law on June 30. Elections under the new organic law were held October 7 and 8, and the newly elected parliament met November 7 of the same year.
Constitutional Development in Czechoslovakia
Authors: Kerner Robert J.
Published: May 2006

The provisional government of the Czechoslovak Republic at Prague was established by virtue of the law of November 13, 1918, on the provisional constitution. Its antecedents may be of some interest to students of constitutional history. The Czechoslovak statesmen take the ground that the ancient Bohemian state never ceased to exist, as is proved by the thrice-made offer of Francis Joseph, as well as the similar offer of ex-Emperor Charles, to be crowned king of Bohemia. They also point out that the Czech nation never recognized the constitution of 1867 which made possible the Austro-Hungarian Ausgleich.
The Merit System and the Higher Offices
Authors: McIlhenny John A.
Published: May 2006

There is no question of national policy so firmly established as the merit system, and on it must finally rest our political and administrative fabric. The system is fundamental, as it underlies all other political reforms. Its processes, therefore, should be adequate and be made to ensure results which will keep pace with the ever increasing functions of government. These processes are especially important in supplying the needs of appointment to the higher technical and administrative positions. The extension of the merit system to higher positions is a logical development of its application to lower positions. The same reasons which require tests of fitness in the latter apply even more strongly to such of the higher positions as have nothing to do with the policies of the administration. Such an extension would have the additional and great advantage that the more important the office affected the more effective must the extension necessarily be in divorcing the office from politics. Character and capacity are being secured in the great body of public employment, and it only remains to take the higher officials whose duties are purely administrative, federal, state and municipal, out of politics, to establish finally in the minds of the people the fundamental truth that positions under a democratic government belong to the people and not to the political party temporarily in power. The higher subordinates in the government employ have administrative control of the work on which our economic structure and our industrial success largely depend; and it must follow that their selection should be made upon proved merit, if that degree of administrative success is to be obtained which the people of this country have a right to expect. It is through the highest officials down to the humblest employees that the government serves the people.
Reorganization of State Government in Oregon
Authors: Barnett James D.
Published: May 2006

The establishment of the system of direct government in Oregon—the initiative and referendum, the direct primary, and the recall of officers—has been followed by several important movements for the reorganization of representative government in all three departments.

The centralization of the state administration is involved in one of the earliest, as it is in the latest, of these movements. In 1909 and 1911 W. S. U'Ren and others of the People's Power League published a proposal for the “concentration of responsibility and power for the enforcement of the laws as nearly as practicable in one public servant,” as it was expressed, by reducing the number of elective officers to two—the governor and the auditor (besides the three proposed “people's inspectors”), and making most of the other state officers as well as the sheriffs and district attorneys both the appointees and the actual subordinates of the governor. The plan was advocated as the means of securing responsibility for the enforcement of the law, economy in administration, and relief from the burden of the ballot. But the proposal was generally condemned by the press as creating “a monster political machine,” a “monarchical” form of government. In view of this opposition and of the fact that the League was at the same time urging radical changes in the legislative department of the state government, the proposal was not submitted to the people.
The Irish Free State Elections of September, 1927
Authors: Pollock James K.
Published: May 2006

The voters of the Saorstat Eireann went to the polls on September 15 to elect a new Dail. This was the fourth election under the P.R. system and the second election of the year. Despite the importance of the issues involved and the strenuous efforts of the two larger parties, the total poll was only 35,000 votes greater than in the previous June. But a total poll of 1,180,000 votes is a good record for the Free State, even though on a percentage basis it does not appear large. The present inefficient state of the register makes a percentage comparison somewhat misleading.

To the student of political institutions the election was interesting because of its bearing on several important matters: proportional representation, the development of the party system, political education, and parliamentary government. Not the least of these was proportional representation. There has been much discussion of P.R. in the Free State, and the Cumann na nGaedheal, or government party, made a promise in the election campaign to modify or abolish the system if returned to office. It remains to be seen whether this pledge can be carried out. But in the meantime it is interesting to point out how the system appears to have operated in the most recent election.

Some of the English newspapers undoubtedly exaggerated the evils of the system, the Sunday Express even saying that “one consequence of the election will be the abandonment of an experiment which distorts rather than expresses the opinion of the voters.”
Administrative Law and the Constitution
Authors: Rosenberry Marvin B.
Published: May 2006

In the constitution of Massachusetts is found the following: “In the government of this commonwealth the legislative department shall never exercise the executive and judicial powers or either of them; the executive shall never exercise the legislative and judicial powers or either of them; the judicial shall never exercise the legislative and executive powers or either of them; to the end it may be a government of laws and not of men.” This is probably the most explicit statement of the doctrine of separation of powers to be found in the constitution of any of the states of this Union. While the doctrine has been set forth in other constitutions in other language, the constitutions of all the states as construed and interpreted have come to have substantially the same meaning. For more than a century, lawyers, courts, political scientists, publicists, and the people generally regarded the separation of the government into coördinate departments as one of the corner-stones of our liberties.

Montesquieu, who had no doubt derived his ideas upon the subject from the writings of Locke and a study of English law, in 1748 published his great work, The Spirit of Laws. In this treatise he gave a new exposition of the doctrine of separation of powers and the reasons for it, in a form which gave it wide currency in the English-speaking world; but this exposition was intended by Montesquieu to be a statement of political theory, and was so accepted by political writers of the time.