bluuebunny/crossref_metadata_2025 huggingface dataset:
Juvenile Spongiotic Gingivitis
Authors: Darling Mark R. , Daley Tom D. , Wilson Aze , Wysocki George P.
Published: July 2007

Background: This article recognizes the microscopic diagnosis of acute spongiotic mucositis as an analog to acute spongiotic dermatitis of the skin and defines a specific clinicopathological entity “juvenile spongiotic gingivitis” within this microscopic spectrum.

Methods: Twenty‐four patients, usually juveniles, with patches of bright red, often slightly thickened, painless, and persistent lesions of the attached gingiva, which may or may not involve the marginal gingiva, were identified by clinical and microscopic features. Immunohistochemical studies for cytokeratins 5/6 and 19, estrogen receptors, and progesterone receptors were completed on 10 of these cases. A comparison to puberty gingivitis, which occurs in the same age group, was done.

Results: Microscopically, the epithelium exhibited hyperplasia, significant spongiosis, loss of keratinization, and a neutrophilic infiltrate, sometimes with microabscess formation, whereas the underlying connective tissue exhibited an acute on chronic inflammatory infiltrate. Full‐thickness epithelial immunostaining for cytokeratins 5/6 and 19 was found, whereas no reactivity was seen for estrogen receptors or progesterone receptors in the specimens.

Conclusions: Juvenile spongiotic gingivitis differs from puberty gingivitis by not needing to show continuity with plaque‐related marginal gingivitis, by a lack of response to hygiene procedures, by an occasional occurrence at ages not related to puberty, and by the absence of sex hormone receptors investigated immunohistochemically in 10 of the cases. We propose juvenile spongiotic gingivitis as a distinct clinicopathological entity.
College Students' Study Time: Course Level, Time of Semester, and Grade Earned
Authors: Landrum R. Eric , Turrisi Rob , Brandel Jessica M.
Published: July 2007

The association of total study time, number of events, time per event ratio, study strategies, and course grades across the semester were examined by linking students' study logs to course performance. There were 37 upper-division and 109 lower-division participants. Students earning As and Bs studied more frequently at the end of the semester but for shorter periods of time than students earning lower grades. Results are discussed in terms of providing college students and faculty with recommendations about learning strategies and time spent studying.
Meaning in Life for Individuals with Physical Disabilities
Authors: Arvig Tyler
Published: July 2007

“What makes your life meaningful?” is a question previous researchers explored with people of various ages, but not of individuals who have significant physical impairments. In this study, 26 individuals with physical disabilities were asked to describe what makes their lives meaningful. Analysis showed human relationships were the most frequently reported source of meaning in life, the sources being family members, friends, and people in the community. The second most frequently cited meaning was service, specifically, helping and educating others, such as other people with physical disabilities.
False Assumptions about Psychopathology, Hysteria and the MMPI-2 Restructured Clinical Scales
Authors: Gordon Robert M.
Published: July 2007

The MMPI-2 Restructured Clinical scales rest on the common behavioral assumption that consistent items can be added to assess all psychopathologies. This may be the case for some unitary symptoms such as anxiety or anger, but not for complex diagnostic conditions such as Hysteria, Post Traumatic Stress Disorder, and Borderline Personality Disorder. These are better understood with a psychodynamic formulation. Psychodynamic theory assumes that internal conflicts and contradictions are a significant feature of many psychopathologies. For example, the new MMPI-2 Restructured Clinical scales eliminated a measure of hysteria. The RC3 Cynicism scale is not an improvement over the MMPI-2 Hysteria scale, as the new scale serves as an example of a failure of the behaviorism to account for complex psychopathology. Making scales more internally consistent and distinct from each other has not produced more external validity and useful measures for many of the psychopathologies found in clinical practice.
Domain Specific Effects of Central Traits in Impression Formation
Authors: Reich Warren A. , Ray Suchismita
Published: July 2007

In a procedure similar to that used in Asch's classic studies in 1946, 125 college students (54 men and 71 women, M age = 20.9 yr., SD =4.8) rated their impression of a hypothetical man or woman who was described by seven stimulus traits. This list included one of four central traits which appeared in the middle of the list: warm, cold, serious, or foolish. The dependent measures were factor scores derived from participants' ratings of 20 traits on social desirability and intellectual desirability. As hypothesized, warm and cold, prototypes of social desirability and undesirability, were associated with judgments of social but not intellectual desirability, and serious and foolish, prototypes of intellectual desirability and undesirability, were associated with judgments of intellectual but not social desirability. In addition, there was evidence of a subtle sex bias: ratings of “foolish” women were higher on social desirability than ratings of “foolish” men.
Temporal Stability of the Czech Translation of the Satisfaction with Life Scale: Test-Retest Data over One Week
Authors: Navrátil Marek , Lewis Christopher Alan
Published: July 2007

The present study supplemented the limited 1999 psychometric data by Lewis, et al. on the Czech translation of the Satisfaction With Life Scale by examining the temporal stability of the measure over a 1-wk. period for 64 Czech undergraduate university students. Analysis indicated stability across the two administrations was very high ( r = .90), and there was no significant change between Time 1 ( M = 23.7, SD = 5.1) and Time 2 ( M = 24.1, SD = 5.5). Short-term test-retest reliability of this Czech translation is supported.
Incidence of Having Dreamed and Conservative Political Attitudes
Authors: Kroth Jerry , Bautista Christine , Bess Joy , Cruickshank Kristen , Stashak Janet
Published: July 2007

The association of political attitudes of conservatives and reports of their having had a dream was investigated. 48 female graduate students in counseling psychology were given the KJP Dream Inventory and the Kerlinger Social Attitude Scale II. Scores on conservative political attitudes were positively correlated with having had Dreams of Falling (.40), Dream Discontentedness (.31), Dreams of Being Chased (.40), and Dreams of Being Famous (.30). Negative correlations were observed between scores showing a conservative political tendency and scores on Openness (−.35), and Uninhibitedness (−.50), as well as incidence of Dreams of Sex (−.29). The character of conservative dreaming is discussed along with the study's relevance to past and subsequent issues in research.
Miscibility of blends of bisphenol‐A‐polycarbonate and poly(styrene‐co‐acrylonitrile‐co‐hydroxystyrene) terpolymer
Authors: Li Guangxian , Mong Shiyun , Jiang Sujun , Ragupathy L. , Cowie J. M. G. , Ferguson R. , Arrighi V.
Published: July 2007

The miscibility of blends of bisphenol‐A‐polycarbonate (BAPC) with the terpolymer poly(hydroxystyrene‐co‐acrylonitrile‐co‐styrene) (OHS‐AN‐S) and the copolymer poly(hydroxystyrene‐co‐acrylonitrile) (OHS‐AN) was investigated. BAPC was found to be miscible with terpolymers incorporating 25–80 mol % hydroxystyrene. The introduction of the acrylonitrile monomer (AN) into poly(styrene‐co‐hydroxystyrene) (PSHS) produces a wider “miscibility window” with BAPC compared with that of blends of BAPC with PSHS i.e. a miscible blend is obtained at relatively lower levels of hydroxyl groups in the terpolymer. However, the miscibility range in terpolymer/BAPC blends is affected by the amount of AN monomer incorporated into the terpolymer. This is probably a consequence of the influence of the AN monomer on the closer spatial correlation between the terpolymer and BAPC chains. BAPC is also found to be miscible with the OHS‐AN copolymer within the composition range 12–50 AN mol % in the copolymer. A triangular phase diagram for binary blends of terpolymer/homopolymer (AxByCz/D) is suggested, to determine the miscible region of the terpolymer compositions in the blends. A model used for predicting the miscibility of binary blends consisting of a homopolymer and a terpolymer was also proposed on the basis of the mean‐field theory, and tested with the experimental results obtained in this work. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Effect of low‐load reinforcing nanofillers on rheological behavior and physical properties of ionic elastomers based on XNBR and MgO
Authors: Rodríguez A. , Ibarra L. , Mora I.
Published: July 2007

The influence of low load reinforcing fillers in carboxylated nitrile rubber (XNBR), crosslinked with magnesium oxide, has been studied. The nanofillers utilized were carbon black, precipitated silica, natural clay, and synthetic silica. The latter filler was obtained by acid lixiviation of a natural magnesium silicate. The rheological behavior of the samples was study by means of capillary (consistency index) and rotational (Mooney viscosity) flows. Through these analyses, higher viscosities, and lower flow indexes were observed for the filled samples. The acid character of silica and clay leads to an increase in vulcanization rates, measured by the cure rate index (CRI) and referring it to the unfilled compound. Moreover, the fillers dilute the ionic microphases formed during the vulcanization process of the XNBR. Since these microphases behave as reinforcing sites, a decrease in tear and abrasion properties takes place. However, the reinforcing effect of the fillers leads to higher values of stress at constant strains. Finally, the variation of glass and ionic transition temperatures with filler addition was analyzed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Decision heuristics as predictors of public choice
Authors: Wang X. T.
Published: July 2007

Two studies examined cognitive and affect‐based heuristics as predictors of public choice. Participants, recruited before the 2004 Presidential Election, identified the issues that would determine their voting decision and provided ratings of importance and Likelihood of Success for these issues (decision cues) regarding each presidential candidate. Both well‐known and new heuristics were evaluated for descriptive fit between predicted and actual voting choices and overall predictive accuracy regarding who the winner of the sample would be. In Study 1, the performance of cue‐weight free simple heuristics, particularly those based on frequency counts, matched or outperformed that of normative Franklin's rule that used both cue values and cue weights. In Study 2, the affect (admiration and contempt)‐based heuristics performed even better. The Take‐The‐Best Emotion heuristic performed as well as the affect heuristics utilizing multiple social emotions. These findings highlight the utility of event frequency‐based and interpersonal affect‐based heuristics in predicting public choice under uncertainty. Copyright © 2007 John Wiley & Sons, Ltd.
Biohorizons
Authors: Moni Roger W. , Moni Karen B. , Poronnik Philip , Lluka Lesley J.
Published: July 2007

We detail the design, implementation and evaluation of an eConference entitled “Biohorizons”, using a presage‐process‐product model to describe the development of an eLearning community. Biohorizons was a summative learning and assessment task aiming to introduce large classes of first‐year Human Biology students to the practices of professional scientists. It was implemented in semester 1 for students enrolled in Pharmacy and Human Movement Studies degree programs, and in semester 2, for Science students. Pairs of students selected a topic of interest in Human Biology, registered into on‐line clusters, then developed and wrote a short scientific paper and accompanying PowerPoint presentation. They then individually participated in an online Discussion. All three tasks were assessed using standards‐referenced assessment rubrics. Learning was supported by eTutors, working in asynchronous mode. Biohorizons was evaluated by analyzing student achievement data, surveys and focus group interviews. Most students were able to achieve high academic standards (global mean scores for semester 1, 85–96%; semester 2, 81–90%). Student evaluations support: 1) the successful integration of eLearning into large classes of Human Biology, 2) the engagement of first‐year students through collaborative learning, and 3) the fostering of learning through challenging assessment relevant to the core practices of professional scientists.
Structure and Reactivity of the Metal Centers of Ribonucleotide Reductases
Authors: Mulliez Etienne , Fontecave Marc
Published: July 2007

The activation of the three classes of ribonucleotide reductases as free radical enzymes is reviewed. Class I uses O2 and a diferric μ‐oxo center to generate a stable tyrosyl protein radical. Class II operates with adensoyl cobalamin as the precursor of a putative transient thiyl protein glycyl radical by the concerted forms an O2‐sensitive protein glycyl radical by the concerted action of an iron–sulfur cluster and (S)‐adensoyl methionine.
Metallacyclodisiladiazanes of Titanium and zirconium; Synthesis, Structure and Polymerization Studies
Authors: Jäger Felix , Roesky Herbert W. , Dora Hendrik , Shak Syed , Noltemeyer Mathias , Schmidt Hans‐Geory
Published: July 2007

A series of metallacyclodisiladiazanes has been prepared. Lithiated (SiMe2NHtBu)2 (1) reacts with TiCl4 · 2 THF to give (SiMe2NtBu)2TiCl (4). Methylation or fluorination of 4 leads to (SiMe2NtBu)2TiMe2 (8) and (SiMe2MtBu)2TiF2 (9), respectively. The reaction of ZrCl4 · 2 THF with lithiated 1 or [SiMe2NH(4‐FC6J4)]2 (2) yields (SiMe2NtBu)2ZrCl2 (5) and [SiMe2N(4‐FC6H4)]ZrCl2 · THF (7), respectively. The lithiated ligand [SiMe2NH(2,6‐iPr2C6H3)]2 (3) reacts with noncoordinated ZrCl4 to give [SiMe2N(2,6‐iPr2C6H3)]2ZrCl2 (6). X‐ray structural analysis of 9 showed it to be a fluorine‐bridged dimer in the solid state. Compounds 4, 6, 8 and 9 were found to be catalysts for the polymerization of ethylene.
Formation of the Digallium Compound [(C5C6)2N3](R)Ga–Ga(R)[N3(C6H5)2] with Two Bis(trimethylsilyl)methyl Groups and Two Terminal Chelating Diphenyltriazenido Ligands
Authors: Uhl Werner , Hann Ingo , Wartchow Rudofl
Published: July 2007

Tetrakis[bis(trimethylsilyl)methyl]digallane (4) 1 reacts with 1,3‐diphenyltriazene to yield two compounds, which were both characterized by a crystal structure determination. The gallium–gallium bond is retained in the yellow derivate [(H5C6)2N3](R)Ga–Ga(R)[N3(C6H5)2 2 [R = CH(SiMe3)2], which is formed by a ligand exchange reaction and shows two terminal chelating triazenido ligands besides two bis(trimethylsilyl)methyl groups; the GaGa bond length is 245.79(6) pm. The second product is the orange dialkyl(diphenyltriazenido)gallium derivative R2Ga[N3(C6H5)2] 3, where the triazene has reacted as an oxidant by the cleavage of the GaGa bond and probably by release of elemental hydrogen.
Synthesis and Properties of Me2Ge‐Bridged Arenes
Authors: König Burkhard , Rödel Martin
Published: July 2007

Linear and cyclic oligomers of Me2Ge‐bridged π‐systems have been obtained by the reaction of carbo‐ and heterocyclic anions and dianions with Me2GeCl2. The spectroscopic properties of the new compounds are compared with analogous carbon‐ and Me2Si‐bridged π‐systems.
Crown Thioether Chemistry: Novel Silver(I) Complexes of 1,3‐Dithiole‐Annelated 1,4,7‐Trithiacyclononane
Authors: Wagner Michael , Drutkowski Ulrkie , Jörchel Peter , Hoyer Eberhand , Olk Ruth‐Maria , Kempe Rhett
Published: July 2007

The coordination chemistry of two crown thioethers 2,5,8,10,12‐pentathiabicyclo[7.3.0]dodeca‐1)9)‐ene‐11‐thione (L) and ‐11‐one (L') with Ag1 has been investigated by structural methods. Both thioethers act as tridentate ligands coordinating the silver ion in a trigonal fashion. In the case L, the 11‐ thione sulfur is coordinated additionally by another silver ion, to yield a polymeric chain with a distorted‐tetrahedral geometry about the metal ion. Despite differing only in its carbonyl chalcogen, L' forms six‐coordinated, monomeric complexes.
Oxozirconium Methacrylate Clusters: Zr6(OH)4O4(OMc)12 and Zr4O2(OMc)12 (OMc = Methacrylate)
Authors: Kickelbick Guido , Schubert Ulrich
Published: July 2007

The crystalline oxozirconium methacrylate clusters Zr6(O‐H)4O4(OMc)12 and Zr4O2(OMc)12 were obtained by reaction of Zr(OnPr)4 with an excess of methacrylic acid and analysed by X‐ray diffraction. The oxide and hydroxide groups are in a μ3‐ bridging mode in both structures, and the methacrylate ligands are chelating or bridging. The zirconium atoms in Zr6(OH)4O4(OMc)12 form an octahedron the cluster having crystalographic C3v symmetry. Each metal atom is square‐antiprismatically coordinated by eight oxygen atoms. In Zr4O2(OMc)12, the zirconium atoms have a distorted butterfly arrangement; their coordination geometry is square‐antiprismatically coordinated by eight oxygen atomes. In Zr4O2)OMc)12, the zirconium atoms have a distorted butterfly arrangement; their coordination geometry is square‐antiprismatic or capped octahedral.
The Biological and Medicinal Chemistry of Bismuth
Authors: Sun Hongzhe , Li Hougyan , Sadler Peter J.
Published: July 2007

Bismuth compounds have been widely used in medicine for more than 200 years, and new bismuth‐containing drugs are now being developed. However the biological chemistry of bismuth is poorly understood. We review here methods for the study of bismuth compounds, and use of Bi(III) in antiulcer, antibacterial, anti‐HIV and radiotherapeutic agents is described. The chemistry of Bi(III) carboxylates and aminocarboxylates is dominated by intermolecular interactions which lead to polymeric structures. Bi(III) exhibits a highly variable coordination number and coordination geometry, and alkoxide ligands can induce a strong stereochemical “lone‐pair effect”. Bi(III) can bind to both Zn(II) sites (e.g. metallothionein) and Fe(III) sites (e.g. transferrin) in proteins. Further work is needed to understand the relationship between the structures and dynamics of bismuth compounds and their bioactivity.
Fully Chlorinated N‐Silyl Amides of Titanium and Tungsten — Crystal Structure of Cl3SiNW(Cl3)N(SiCl3)2
Authors: Schwarze Bernd , Milius Wolfgang , Schnick Wolfgang
Published: July 2007

The reaction of hexachlorodisilazanyllithium (Cl3Si)2NLi (1), with TiCl4 leads selectively to the novel fully chlorinated amides (Cl3Si)2NTiCl3 (2) or [(Cl3Si)2N]2 TiCl2 (3), respectively, depending on the molar ratio of the starting materials. The analogous reaction of 1 with WCl6 yielded the amide imide Cl3SiNW(Cl3)N(SiCl3)2 (5) by elimination of SiCl4. The relative amounts of the starting materials had no effect on the formation of 5. 14/15N‐ and 29Si‐NMR data on the starting materials and products show significantly different effects, when compared with those of analogous N‐trimethylsilyl derivatives, due to the lower energy of the electrons in the NSi and NM ß bonds. The crystal structure of 5 (triclinic, space group P1) was determined by X‐ray structure analysis.
Organophosphorus Compounds, 118. Reactions of 1‐Chloro‐1H‐phosphirenes with Nucleophiles
Authors: Heydt Heinrich , Ehle Michael , Haber Steffen , Hoffmann Jürgen , Wagner Oliver , Göller Andreas , Clark Timothy , Regitz Manfred
Published: July 2007

The halogen atoms in the 1‐chloro‐1H‐phosphirenes, 5a–c, are easily substituted on reaction with organolithium and Grignard reagents, 14a–p, with formation of the corresponding O‐, N‐, C‐, Si‐, and Ge‐substituted 1H‐phosphirenes, 15a–t. C1/H exchange reactions also occur on reaction with lithium metal hydrides (5a → 17). Furthermore, substitution reactions are also realized with the alkali metal borates, 18a–g (→19a–g); the same is true for reactions with trimethylsilyl cyanide and azide (→22a–d). Some of the substitution products have been characterized in the form of their metal complexes, 16, 23, 24, and 25.
Compounds of Germanium and Tin, 2l. A Tetraaryldigermene with a Short Germanium‐Germanium Double Bond and a Nearly Planar Environment of Both Germanium Atoms
Authors: Weidenbruch Manfred , Stürmann Martin , Kilian Hartmut , Pohl Siegfried , Saak Wolfgang
Published: July 2007

Treatment of GeCl2 · dioxane with the Grignard reagent RMgBr (R=2‐tBu‐4,5,6‐Me3C6H) furnishes the tetraaryldigermene R2GeGeR2 (8). X‐ray structure‐analysis of 8 reveals a short GeGe double bond, a nearly planar environment of both germanium atoms and extremely widened CGeC angles of 128°. In solution, 8 dissociates into two germylene molecules R2Ge, which can be trapped with oxygen or by [4+1] cycloaddition reactions with 1,4‐dihetero‐1,3‐dienes. A similar cycloadduct of a stannylene wa obtained by thermolysis of (R′2Sn)3 (R′=2,4,6‐iPr3C6H2), in the presence of a 1,4‐diazabutadiene and characterized by an X‐ray structure‐analysis.
Ligand‐ Substrate Communication in Group 4 Aminopyridinato Complexes
Authors: Oberthür Markus , Hillebrand Gerhard , Arndt Perdita , Kempe Rhett
Published: July 2007

Tris(aminopyridinato) zirconium and ansa‐aminopyridinato titanium complexes have been sythesized. The reaction of (TMS‐APy)3‐Zr‐Cl (4‐methyl‐2‐trimethylsilyl‐aminopyridine=TMS‐APy‐H) with trimethylsilylbutadiynyl lithium generated in situ affords (TMS‐APy)3ZrCCCCTMS (1). (TMS‐apy)3‐Zr‐Me2 (2). Compound 2 shows an agostic interaction of the dimethylamido moiety. The reaction of Ti(NMe,2),4 with silox(Apy‐H)21,3‐di(4′‐picolin‐2′‐yl‐amino)‐1,1,3,3‐tetraisopropyldisiloxane=silox (APy‐H)2] gives rise to silox(Apy)2‐Ti‐(NMe2)2‐Ti‐[NMe,2)2 (3). Complex 3 reacts with ε‐caprolactam to form a caprolactamato complex (4). X‐ray crystal structure analyses of 1, 2, 3 and 4 are reported. The complexes 1, 2, 3 and 4 may be considered to be strained donor‐functionalized amido(metal) complexes due to the η2 binding mode of the ligand cores,
TMS‐APy and silox(APy)2, to meet the requirements of the ancillary coordinated substrates is observed. Thus, aminopyridinato complexes seem to be valuable model compounds for investigations of ligand‐substrate communications in early transition metal chemistry.
N‐Alkylation of Ammine—Undecahydro‐Closo‐dodecaborate(1−)
Authors: Peymann Toralf , Lork Enno , Schmidt Martin , Nöth Heinrich , Gabel Detlef
Published: July 2007

The reactions of the ammine‐undecahydro‐closo‐dodecaborate(1−) anion with alkyl halides have been studied in detail. The degree of alkylation of the nitrogen was found to be dependent upon the steric demands of the alkyl groups. The derivatives were characterized by NMR and infrared spectroscopy. Four compounds were crystallized for single crystal X‐ray diffraction studies. The tetrahedral coordination of the nitrogen atom of the bis‐alkylated derivatives was found to deviate towards planarity with increasing steric hindrance of the substitutents. ‐ The syntheses, crystal structures, and spectral properties of four N‐alkyl derivatives of [H3NB12H11]‐, ammine—undecahydro‐closo‐dodecaborate(1−) (3), are reported. Alkylation of 3 with ethyl iodide was achieved in dimethyl sulfoxide using potassium hydroxide as base. This led to orthorhombic crystals of [N(nC4H94][(CH3CH2)3NB12H11] (4). The reaction of 3 with benzyl chloride resulted in the bisbenzylated product, isolated as triclinic crystals of [PPN][(C6H5CH2)2 NHB12H11] (5). The alkylation of 3 with 2‐bromopropane gave a mixture of the mono‐ and bisalkylated products. The monoalkylated derivative [PPN][(CH3)2CH)NH2–12H11] (6, crystallized in the triclinic space group p1) and the bisalkylated product [PPN]{[(CH3)2NHB12H11) (7, monoclinic, P21./c) were separated on the basis of their different water solubilities. The solid‐state structures of the compounds 4–7 revealed a slight distortion of the B12 icosahedron. The length of the B(1)–N(1) bond was found to be dependent on the steric requirements of the attached amine, e.g. primary amine < secondary amine < tertiary amine. This is demonstrated by the variation in the BN bond length; from 157.8(2) pm for 6, 158.5(5) pjm for 5, 160.0(3) pm for 7, to 163.7(6) pm for 4.
Mono‐ and Bicyclic Organometallic Ring Systems with Exocyclic CC and CS Bonds
Authors: Werner Helmut , Xiaolan Liu , Peters Karl , von Schnering Hans Georg
Published: July 2007

The cobaltaheterocycles [C5H5Co{κ2(C,S)‐C(=CH2)‐N(R)C(=S)S](PMe2Ph)] (5‐7), which contain both an exocyclic CC and CS bond, were prepared from the iminoacylcobalt compounds [C5H5Co(C(CH3)=NCH} (PMe2Ph)]I (2‐4) on treatment with either CS2/NaOCH3 or K[S2CNMe2], respectively. While protonation of 5 (R = CH3) and 7 (R = CH2Ph) with HBF4 occurs at the exocyclic CCH2 bond to give cations containing a CoC(CH3)N(R)C(=S)S ring, the methylation of 5 and 7 with [OMe3]BF4 takes place at the exocyclic CS bond and generates five‐membered heterocycles heterocycles with an SCH4 substituent. The reaction of 5‐7 with S8 leads to the elimination of the phosphane ligand and affords the bicyclic dithiolenecobalt complexes 14 ‐ 16 in moderate to good yields. On treatment of 5‐7 with C2(CO2R′)2 (R′ = Me,Et), an insertion of the alkyne into the CCH2 bond occurs and five‐membered ring systems 19‐22 with an unsaturated exocyclic =C(CO2R′)‐C(CO2R′)=CH2 group are formed. As in the case of 5 and 7, protonation and methylation reactions of 19 also take place at different sites leading to cations with either a delocalized CoCN or NCS unit.
Chemistry in Environmentally Benign Media, 8 Hydroxymethyl Functionalized Phosphanes as Building Blocks to new Water‐Soluble Gold(I) Complexes ‐ synthesis, Characterization, and X‐ray crystal Structures of Novel Tetrahedral [Au{P(CH2OH)3}4]+ and Trigonal Planar [Au(Ph2PCH2OH)3]+ Gold (I) Complexes
Authors: Berning Douglas E. , Katti Kattesh V. , Barnes Charles L. , Volkert Wynn A.
Published: July 2007

The reactions of water‐soluble phosphanes P(CH2OH)3 (1) and Ph2PCH2OH (2) with NaAuCl4 in aqueous or alcoholic media, produced the water/alcoholic‐soluble AuI complexes [Au(Ph(CH2OH)3)4]+ (3) and [Au(Ph2PCH2OH)3+ (4) in near quantitative yields. The X‐ray structures of 3 and 4, reported in this paper, confirm the structures of these new generation of water‐soluble transition metal complexes. All compounds were characterized by 1H‐, 13C‐, 31P‐NMR spectroscopy and mass spectrometry. The structures of 3 and 4 were determined by X‐ray crystallography.
Complex Catalysis, XLIX On the Coordination of Olefins and Secondary Amines at the Cationic [2,6‐Bis(diphenylphosphanylmethyl)pyridine]rhodium(I) Fragment [Rh(PNP)]+ ‐ Synthesis and Characterization of [Rh(PNP)(L)]X (L = Ethylene, Styrene, HNR2; X = BF4, PF6, CF3SO3)
Authors: Hahn Christine , Sieler Joachim , Taube Rudolf
Published: July 2007

The cationic rhodium(1) complexes [Rh(PNP)(C2H4)]X; X = BF4 (1a), PF6 (1b), CF3SO3 (1c ) were prepared by addition of the tridentate ligand 2,6‐bis(diphenylphosphanylmethyl)pyridine (PNP) to a solution of [Rh(C2H4)2(solv)2]X (solv = acetone or THF) under ethylene. The complexes were characterized by IR and 1H‐, 13C‐, and 31P‐NMR spectroscopy. The coordination of two ethylene molecules at the [Rh(PNP)]+ fragment could be detected by dynamic proton resonance of a solution of 1a under free ethylene. The styrene complex [Rh(PNP)(styrene)]BF4 (4) was obtained by substitution of the ethylene from 1a with an excess of styrene. The π coordination of C2H4 and styrene in 1a and 4 respectively was confirmed by X‐ray crystal structure analysis. The olefin complexes react with an excess of the secondary amine to give the corresponding amine complexes [Rh(PNP)(HNR2)]X; HNR2 = piperidine (5), HNMe2 (6 ), HNEt2 (7). Conversly, the amine could be released from the amine complexes with an excess of ethylene at low temperature by the formation of the ethylene complex 1.
Synthesis and Iron‐Binding Properties of Protochelin, the Tris (catecholamide) Siderophore of Azotobacter vinelandii
Authors: Dubme Anne‐Kathrin , Hider Robert Charles , Khodr Hicham Hussein
Published: July 2007

Protochelin, the tris(catecholamide) siderophore recently identified in the culture medium of A. vinelandii, can be synthesised by coupling of suitably protected azotochelin and aminochelin derivatives in preparative yields, Based on the ligand protonation constants of pK1 = 6.67, pK2 = 8.09 and pK3 = 9.68, the proton‐independent stability constant for ferric protochelin could be estimated to be 1044.6. The solubilisation of FeIII hydroxide by protochelin has been investigated spectrophotometrically in aqueous solution at pH = 7. Since the production of protochelin by A. vinelandii depends on high molybdate levels in the growth medium, the studies have been carried out in the presence as well as in the absence of an equimolar amount of molybdate. Although the protochelin promoted dissolution of FeIII hydroxide is delayed significantly in presence of molybdate, the effect is far less pronounced than the one observed for azotochelin, the bis(catecholamide) siderophore of A. vinelandii.
Zinc Pyrazolylborate Complexes with Phenoxide and Alkoxide Ligands
Authors: Walz Rainer , Weis Karl , Ruf Michael , Vahrenkamp Heinrich
Published: July 2007

The zinc hydroxide complexes Tp*Zn‐OH of highly substituted pyrazolylborate ligands react with phenols, and alcohols, of sufficient acidity, in a condensation reaction with release of H2O. Starting with phenols the following were attached:phenolate, p‐nitropehnolate, o‐vanillinate, o‐hydroxymethylphenolate, o,o‐bis(hydroxymethyl) ‐p‐methylphenolate. Whilst aliphatic alcohols and benzyl alcohol did not react, their derivatives, with highly electronegative substituents could be incorporated. Thus, the arylmethoxides OCH2C6F5 and OCH2C6H4NO2‐p, as well as the alkoxides OCH2CF3 and OCH2CCl3, were attached. 2‐Mercaptoethanol was bound via its thiolate function. The crystal structures of TpCum,Me ZN‐OC6H4NO2‐p,TpCum,Me ZN‐OCH2‐C6F5, TpCum,Me ZN‐OCH2CF3, TpCum,Me ZN‐OCH2CCl3 and TpCum,MeZn‐SCH2CH2OH were determined.
New Coupling Reactions and Phosphorylations Using Organozinc Reagents
Authors: Knochel Paul , Langer Falk , Longeau Alexia , Rottländer Mario , Stüdemann Thomas
Published: July 2007

This Microreview on the chemistry of organozinc reagents starts by briefly showing the methods of preparation of organozinc compounds and then discusses the considerable synthetic utility of zinc organometallics for the formation of new carbon‐carbon bonds in the presence of transition‐metal catalysts. Finally, the use of organozinc chemistry for the preparation of polyfunctional and chiral phosphanes is described.
Synthesis and Structure of Allenyl‐Substituted η6‐Benzene(tricarbonyl)‐chromium Complexes
Authors: Müller Thomas J. J. , Ansorge Markus
Published: July 2007

The Cr(CO)3‐complexed η6‐phenylpropargylic alcohols 3 react in a displacement rearrangement with thionyl chloride or chlorodiphenylphosphane to give the chloro‐ or phosphoryl allenyl substituted η6‐phenyl complexes 4 and 6, respectively. In the X‐ray crystal structure of the novel organometallic allenic derivatives 4b and 6b the vicinal chloro or phosphoryl substituent and the benzene(tricarbonyl)chromium fragment are arranged coplanarily. Palladium/copper‐catalyzed couplings of the chloroallene 4b with terminal alkynes disclose a facile access to ynallene derivatives 8, novel carbon‐rich organometallic π‐systems.
Tripod Ligands Containing a Mixed P/N/S Doner Set: Synthesis and Coordination Chemistry
Authors: Jacobi Albrecht , Huttner Gottfried , Winterhalter Ute
Published: July 2007

The preparation of neopentane‐based tripod ligands CH3C(CH2X)(CH2Y)(CH2Z( 3 (X = NR2, NHR; Y = PR2; Z = PR2, SR, S−) in a convergent manner is described. The procedure is based on the aminolytic cleavage of functionalized oxetanes CH3C(CH2OCH2)CH2R 1 by primary or secondary amines, leading to functionalized amino alcohols CH3C(CH2NHR)(CH2OH)(CH2R) or CH3C(CH2NR2)‐(CH2OH)(CH2R) 2. The appropriate activation of the R (e.g. OR) and OH groups present in 2 allows for substitution vs. SR or PR2 donor functions. Depending on the nature of the groups present in each reaction step, various protection and groups present in each reaction step, various protection and deprotection steps have to be taken in the course of this type of preparation of the tripod ligands 3. By reaction with (CH3CN)3Mo(CO)3, ligands 3 form Mo(CO)4 derivatives 4 or Mo(CO)3 derivatives 5, depending on the reaction conditions. In compounds 4, the ligands are coordinated in a bidentate mode with the soft donor atoms (P, S) coordinated and the hard donor function playing the role of the dangling arm. In the trihapto bonding mode present in 5, all three donor functions, two soft (P, S) and one hard (NHR′, NR′2), are coordinated. The two types of coordination compounds may be interconverted: 4e (X = NMe2′ Y = PPh2, Z = SiPr) with a non‐coordinating CH2NMe2 group is transformed into 5c upon photolytic decarbonylation. Under 1 bar CO at 20°C, 5c reverts to 4e. X‐ray structure analysis of a series of compounds of types 4 and 5 reveals characteristics of the relevant conformational patterns. All compounds have been fully characterized by the standard analytical techniques (NMR, MS), as well as elemental analysis.
Coronary artery ectasia–Is it time for a reappraisal?
Authors: Ramappa P. , Kottam A. , Kuivanemi H. , Thatai D.
Published: July 2007

Coronary artery ectasia (CAE) is a well recognized clinical entity encountered during diagnostic cardiac catheterization. The etiopathogenesis of this condition is poorly understood. Due to the frequent presence of associated obstructive coronary artery disease it is considered to be a maladaptive process of atherosclerosis. Based on its association with aortic aneurysm, coronary ectasia is considered to be caused by genetic abnormalities. It is usually not a benign condition, as normal smooth laminar flow is disrupted with a potential of thrombus formation. The role of long‐term anticoagulation in this condition has not been well established. It is speculated that with increasing use of newer, noninvasive modalities the incidence of ectasia may rise, therefore necessitating this review. Copyright © 2007 Wiley Periodicals, Inc.
Portable enhanced external counterpulsation for Acute Coronary Syndrome and cardiogenic shock: A pilot study
Authors: Cohen, Joshua , Grossman, William , Michaels, Andrew D.
Published: July 2007

Background

Enhanced external counterpulsation (EECP) currently is used as an outpatient therapy for patients with refractory chronic angina.

Hypothesis

We sought to determine the safety and feasibility of a portable EECP unit to treat patients with acute coronary syndrome and/or cardiogenic shock in the coronary care unit (CCU).

Methods

Ten patients with acute coronary syndrome and/or cardiogenic shock who were not considered candidates for invasive intra‐aortic balloon counterpulsation (IABP) by the treating cardiologist were prospectively enrolled in this single‐center study. Each patient received 2–4 one‐hour EECP treatments performed at the bedside in the CCU. Anticoagulation or recent femoral access was not an exclusion criterion.

Results

The mean age was 58 ± 19 years (range 28–81), and half were women. Patients had either acute coronary syndrome alone (n = 4), cardiogenic shock alone (n = 3), or both (n = 3). The cardiac indications for study enrollment included: acute inferior wall ST‐segment elevation myocardial infarction with cardiogenic shock (n = 2), non‐ST‐segment elevation myocardial infarction with postinfarction angina (n = 2) or heart failure (n = 1), unstable angina with refractory rest angina (n = 2), cardiogenic shock from ischemic cardiomyopathy with severe mitral regurgitation (n = 1), and cardiogenic shock from nonischemic cardiomyopathy (n = 2). No adverse events were recorded during or as a consequence of EECP therapy, including no bleeding complications, no heart failure exacerbations, and no skin breakdown. The portable EECP unit did not interfere with ongoing critical care nursing.

Conclusions

EECP is safe and feasible for acute bedside therapy of critically ill patients with acute coronary syndrome and/or cardiogenic shock who are not candidates for IABP. Copyright © 2007 Wiley Periodicals, Inc.
Amphiphilic Poly[(propylene glycol)‐block‐(2‐methyl‐2‐oxazoline)] Copolymers for Gene Transfer in Skeletal Muscle
Authors: Brissault Blandine , Kichler Antoine , Leborgne Christian , Jarroux Nathalie , Cheradame Hervé , Guis Christine
Published: July 2007

Amphiphilic triblock copolymers such as poly(ethylene glycol‐b‐propylene glycol‐b‐ethylene glycol) PE6400 (PEG13‐PPG30‐PEG13) have been recently shown to promote gene transfer in muscle. Herein we investigated the effect of a chemical change of the PEG moiety on the transfection activity of these compounds. We synthesized new amphiphilic copolymers in which the PEG end blocks are replaced by more hydrophilic poly(2‐methyl‐2‐oxazoline) (PMeOxz) chains of various lengths. The resulting triblock PMeOxz‐PPG‐PMeOxz compounds were characterized by NMR, SEC, TGA, and DSC techniques and assayed for in vivo muscle gene transfer. The results confirm both the block structure and the monomer unit composition (DPPG/DPMeOxz) of the new PPG34‐PMeOxz41 and PPG34‐PMeOxz21 triblock copolymers. Furthermore, in vivo experiments show that these copolymers are able to significantly increase DNA transfection efficiency, despite the fact that their chemical nature and hydrophilic character are different from the poloxamers. Overall, these results show that the capacity to enhance DNA transfection in skeletal muscle is not restricted to PEG‐PPG‐PEG arrangements.
Generation of a conditional Ppap2b/Lpp3 null allele
Authors: Escalante‐Alcalde Diana , Sánchez‐Sánchez Roberto , Stewart Colin L.
Published: July 2007

Lpp3, formerly known as Pap2b, is a lipid phosphohydrolase enzyme. Some of its substrates and products are lipids with potent biological and signaling activities such as phosphatidic acid, lysophosphatidic acid, sphingosine‐1‐phosphate, diacylglycerol, sphingosine, and ceramide. Lpp3 is dynamically expressed during development and is widely distributed in adult tissues. Targeted inactivation of Lpp3 gene (Ppap2b) in the mouse results in embryonic lethality because of defects in extraembryonic vascular development and gastrulation. To study the participation of Lpp3 later in development and in specific cell lineages we generated a conditional allele of Ppap2b. This was accomplished by flanking critical exons, responsible for its catalytic activity with loxP sites. A generalized Cre‐mediated recombination of this allele yielded a phenotype fundamentally identical to our previously reported Ppap2b null allele. genesis 45:465–469, 2007. Published 2007 Wiley‐Liss, Inc.
A fate map of Tbx1 expressing cells reveals heterogeneity in the second cardiac field
Authors: Huynh Tuong , Chen Li , Terrell Phillip , Baldini Antonio
Published: July 2007

Tbx1 is required for the expansion of second heart field (SHF) cardiac progenitors destined to the outflow tract of the heart. Loss of Tbx1 causes heart defects in humans and mice. We report a novel Tbx1Cre knock‐in allele that we use to fate map Tbx1‐expressing cells during development in conjunction with a reporter and 3D image reconstruction. Tbx1 descendants constitute a mesodermal cell population that surrounds the primitive pharynx and approaches the arterial pole of the heart from lateral and posterior, but not anterior directions. These cells populate most of the outflow tract with the exception of the anterior portion, thus identifying a population of the SHF of distinct origin. Both myocardial and underlying endocardial layers were labeled, suggesting a common origin of these cell types. Finally, we show that Tbx1Cre‐positive and Tbx1Cre‐negative cell descendants occupy discrete domains in the outflow tract throughout development. genesis 45:470–475, 2007. Published 2007 Wiley‐Liss, Inc.
Organic Photochemical Rearrangements of Triplets and Zwitterions; Mechanistic and Exploratory Organic Photochemistry
Authors: Zimmerman Howard E. , Suryanarayan Vijay
Published: July 2007

There has been some controversy about the mechanisms of reactions of enones and dienones. The question has been whether a zwitterion or diradical is involved as the intermediate. In the case of ground state species it has not been recognized that zwitterions may have diradical character. In triplet reactions there is the question of whether the rearrangements take place at the initial T1 stage or subsequently as S0 ground state zwitterions or diradicals. We now have some new rearrangements bearing on these questions. In some cases it is the triplet which rearranges, while in others it is the S0 zwitterion. The zwitterion vs. diradical nature of the S0 species has been assessed by both experimental as well as theoretical means. Similarly, both experiment and computational theory have been used to determine at what stage the triplet rearrangements occur and to determine the characteristics of the rearranging species. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Geomorphic and riparian forest influences on characteristics of large wood and large‐wood jams in old‐growth and second‐growth forests in Northern Michigan, USA
Authors: Morris Arthur E. L. , Goebel P. Charles , Palik Brian J.
Published: July 2007

Large wood (LW; pieces with diameter greater than 10 cm and length greater than 1 m) and large‐wood jams (LWJs; two or more pieces of LW in contact with each other) are important components of stream ecosystems that are often distributed along stream channels in response to geomorphic and riparian forest factors that interact hierarchically. As a result, information on these relationships is valuable for predicting patterns of wood accumulation and characteristics of individual pieces of wood. We studied relationships between geomorphic and riparian factors and LW and LWJ structure in different geomorphic settings associated with old‐growth and second‐growth settings in Upper Michigan. We used redundancy analysis (RDA) and regression tree analysis to evaluate changes in LW and LWJ structural characteristics among geomorphic and riparian forest settings. Geomorphic factors explained 38·5% of the variability in LW and LWJ characteristics, riparian forest factors uniquely explained 18·4% of the variance and the intersection of the two categories of environmental factors (i.e. the redundant portion) was 29·8%. At the landscape scale, our multivariate analyses suggest that the presence of rock‐plane bedding was an important predictor of the number of LWJs and the percent of channel spanned by LWJs. Our analyses suggest differences in relationships between geomorphic factors and LW and LWJ structure. Channel width, distance from headwaters, gradient and sinuosity were identified by regression tree analyses as the most important variables for predicting LW characteristics, while channel width and confinement were the most important variables for predicting LWJ characteristics. Old‐growth settings generally contained a higher proportion of conifer and LW (both in and out of LWJs) with greater diameter and volume than in second‐growth settings. Our study supports the view that restoration of wood to streams will benefit from considering the associations of wood structure with landscape and reach‐scale geomorphology. Copyright © 2007 John Wiley & Sons, Ltd.
The river‐bed: a dynamic store for plant propagules?
Authors: Gurnell Angela , Goodson Joanne , Thompson Ken , Clifford Nick , Armitage Patrick
Published: July 2007

This paper investigates temporal variations in the abundance, species composition and richness, and spatial distribution of plant propagules stored on river‐beds.

Samples of the surface layers of river‐bed sediments were obtained from two reaches of the River Frome, Dorset, UK, and one reach of the River Tern, Shropshire, UK. Samples were taken from the same bed locations on four occasions spaced at approximately four monthly intervals. Following greenhouse germination trials, 11 384 viable propagules of 105 species were identified in 192 channel bed samples. On average, 32% of the species found in the propagule samples were not present in the channel and riparian vegetation. Most of these additional species were wetland and terrestrial rather than aquatic species. The number of species and density of propagules stored on the river‐bed varied through time and between reaches. These findings indicate that the channel bed is a dynamic store for viable propagules, including a large proportion of species that are not found locally. These propagules are available for redistribution across river‐banks and floodplains during high river flows.

Propagules were preferentially stored within particular bed habitats. On the Tern, the most retentive habitats were close to the channel margins and adjacent to riparian vegetation and trees. On the Frome, stands of emergent vegetation along the channel margin were the most retentive habitat, and were also associated with trapping of finer sediment and organic matter. This habitat provides an aggrading environment at the bank toe that could potentially offer germination sites for the non‐aquatic propagules that are stored. Germination and growth of wetland and terrestrial plants during bank profile aggradation and lateral extension would provide root reinforcement and flow resistance across the changing bank profile. The preferential accumulation of sediment and species‐rich propagules around stands of marginal emergent vegetation is indicative of a subtle coupling of geomorphological and ecological systems. Copyright © 2007 John Wiley & Sons, Ltd.
Microarray analyses of transdifferentiated mesenchymal stem cells
Authors: Schilling Tatjana , Küffner Robert , Klein‐Hitpass Ludger , Zimmer Ralf , Jakob Franz , Schütze Norbert
Published: July 2007

The molecular events associated with the age‐related gain of fatty tissue in human bone marrow are still largely unknown. Besides enhanced adipogenic differentiation of mesenchymal stem cells (MSCs), transdifferentiation of osteoblast progenitors may contribute to bone‐related diseases like osteopenia. Transdifferentiation of MSC‐derived osteoblast progenitors into adipocytes and vice versa has previously been proven feasible in our cell culture system. Here, we focus on mRNA species that are regulated during transdifferentiation and represent possible control factors for the initiation of transdifferentiation. Microarray analyses comparing transdifferentiated cells with normally differentiated cells exhibited large numbers of reproducibly regulated genes for both, adipogenic and osteogenic transdifferentiation. To evaluate the relevance of individual genes, we designed a scoring scheme to rank genes according to reproducibility, regulation level, and reciprocity between the different transdifferentiation directions. Thereby, members of several signaling pathways like FGF, IGF, and Wnt signaling showed explicitly differential expression patterns. Additional bioinformatic analysis of microarray analyses allowed us to identify potential key factors associated with transdifferentiation of adipocytes and osteoblasts, respectively. Fibroblast growth factor 1 (FGF1) was scored as one of several lead candidate gene products to modulate the transdifferentiation process and is shown here to exert inhibitory effects on adipogenic commitment and differentiation. J. Cell. Biochem. 103: 413–433, 2008. © 2007 Wiley‐Liss, Inc.