347 research outputs found

    An existence theorem for stationary discs in almost complex manifolds

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    AbstractAn existence theorem for stationary discs of strongly pseudo-convex domains in almost complex manifolds is proved. More precisely, it is shown that, for all points of a suitable neighborhood of the boundary and for any vector belonging to certain open subsets of the tangent spaces, there exists a unique stationary disc passing through that point and tangent to the given vector. This result gives a generalization of a theorem of B. Coupet, H. Gaussier and the second author, originally proved only for almost complex structures which are small deformations of an integrable one

    How the Ji’kmaqn Came to Spiro: Possible Additions to the Inventory of Sound-Making Instruments Depicted in the Spiro Engravings

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    While doing research on turtle shell rattles the author stumbled onto a photograph of a rare and unusual idiophone whose exact likeness appears twice in one of the engraved shell images from Spiro. This paper describes the instrument and the Spiro image and discusses how an instrument currently found only in the Maritime Provinces of Canada may have come to be portrayed on a marine shell cup found at Spiro

    Polycyclic Spiro Lignans and Biphenyl Tetrahydrofuranone Lignans from Gymnotheca involucrata

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    Four rare polycyclic spiro lignans (1-4) and four new biphenyl tetrahydrofuranone lignans (5-8) were isolated from the whole plant of Gymnotheca involucrata. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analysis and the absolute configuration of 1 was confirmed by single crystal X-ray diffraction. Bioassay results showed that compounds 2 and 6 exhibited weak antifungal activity against Uromyces viciae-fabae at 100 ppm in leaf-disc assays, while compound 3 demonstrated moderate insecticidal activity against Diabrotica balteata at 500 ppm in an artificial diet assay

    Synthesis of spiro[4.4]nonane-containing functional organic molecules

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    Spiro[4.4]nonane features are an important scaffold in many applications such as enantioenriched ligands, functional materials, natural products, and polymers. Excited by the prospect of the spiro[4.4]nonane scaffold, its structural intricacy still appears challenging in chemical synthesis. Many functional organic molecules possessing spiro[4.4]nonane scaffold(s) have recently been reported and synthesized. We provide a Minireview highlighting such advancements and discuss the future opportunities of spiro[4.4]nonane scaffolds in organic chemistry. Representative examples from 2019 to 2024 are discussed. © 2024 The Author

    Organocopper(III) Spiro Complexes: Synthesis, Structural Characterization, and Redox Transformation

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    Reductive elimination of Cu(III) intermediates is often proposed as a key step in many copper catalyzed or-mediated formation of or C-heteroatom bonds. However, there still lacks concrete evidence on this key :step, mainly because Cu(III) complexes are usually too unstable to be isolated and structurally characterized. In this work, novel organocopper(III) spiro complexes and their analogons organocopper(I) spiro complexes were synthesiied and structurally characterized. Single-crystal X-ray structural analysis revealed that the spiro Cu(III) atom adopted a distorted square-planar geometry while its corresponding, spiro Cu(I) atom was tetrahedrally coordinated. A redox transformation between these spiro Cu(I) and Cu(Ill) complexes was experimentally observed by reacting with reductants or oxidants, respectively. As concrete evidence, the organocopper(III) spiro compounds were found to form C-C bonds intramolecularly via reductive elimination.National Natural Science Foundation of China [21372012, 21690061]SCI(E)ARTICLE3913688-1369113

    Jugenderinnerungen aus Hessischen Judengemeinden.

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    Salomon Spiro's grandfather, a student at the Yeshiva of Rabbi Seckel Wormser, was a well-respected Jewish scholar and teacher at a Jewish elementary school. His son, Salomon's father, followed him in this position. Description of rural Jewish life in Northern Hesse. Recollections of the celebration of Jewish festivals and rituals. Antisemitism of the environment. The author describes the difficult relationship with his father due to his ambition to have his son become a Jewish scholar. Reinforced Jewish education. Brief career in the synagogue chorus and as an auxiliary cantor. Salomon attended the humanistic high school (Gymnasium) in Hersfeld, a town known for the antisemitic attitudes of its inhabitants. Incidents of discrimination and assaults at school. Strict observance of Jewish rites under the supervision of the leading rabbi in the Jewish community of Fulda. Opposition to Zionist activities. After graduation in 1904 Salomon Spiro attended the Breuer Yeshiva of the Frankfurt "Austrittsgemeinde". He quit his studies at the yeshiva after a short time due to the strict orthodox environment and its intolerance of liberal developments. Beginnings of university studies in Wuerzburg.Salomon Spiro was born in Schenklengsfeld (Hessen) in 1885 to a family of Jewish teachers. He briefly attended the orthodox Breuer Yeshiva in Frankfurt am Main.Synopsis in fileFuldaWuerzburgAntisemitismHolidays, JewishJewish communitiesJews, liturgy and ritualUniversities and collegesYeshiva (Frankfurt am Main)Spiro, Salomon Bae

    Effects of heteroatom substitution in spiro-bifluorene hole transport materials

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    Three new spirofluorene-based hole transport materials, Spiro-S, Spiro-N, and Spiro-E, are synthesized by replacing the para-methoxy substituent in 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (Spiro-MeOTAD) with methylsulfanyl, N,N-dimethylamino and ethyl groups. Their properties as hole transport materials in perovskite solar cells are investigated. The impact of replacing the para-methoxy substituent on bulk properties, such as the photophysical properties, HOMO/LUMO energy level, hole extraction properties and morphologies of perovskite thin films are investigated. Their optoelectronic and charge-transport properties and performance in perovskite solar cells are compared with the current benchmarked and structurally-related hole transport material (HTM) Spiro-MeOTAD. Surprisingly, the methylsulfanyl substituted spirofluorene shows the highest power conversion efficiency of 15.92% among the investigated spirofluorenes, which is an over 38% increase in PCE compared with that of Spiro-MeOTAD under similar device fabrication conditions.Shenzhen Science and Technology Research Grant [JCYJ20140509093817690]; Shenzhen Key Laboratory of Organic Optoelectromagnetic Functional Materials of Shenzhen Science and Technology Plan [ZDSYS20140509094114164]; Shenzhen Peacock Program [KQTD2014062714543296]; Nanshan Innovation Agency Grant [KC2015ZDYF0016A]; Guangdong Key Research Project [2014B090914003, 2015B090914002]; National Basic Research Program of China (973 Program) [2015CB856505]SCI(E)[email protected]

    Leave for Appeal: Departure as a Requirement for Review of Deportation Orders

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    In this Article, Mr. Spiro addresses the congressional amendments to the Immigration Naturalization Act meant to combat the legal maneuvers calculated to defeat the execution of deportation orders. The addition of section 106 was meant to prohibit all appeals of deportation orders under which an alien had already departed the United States. The author analyzes the legislative history of the provision and notes that Congress intended to the departure rule to apply even in more egregious cases of INS misbehavior. The author discusses federal circuit law and finds that neither the rule nor its exception best serve the dual objectives of deterring manipulative delay while affording fairness to aliens seeking to challenge the finality of their deportation. To combat the filing of frivolous appeals, the author recommends amending section 106 so that deportation appeals be permitted only from abroad

    Mammon and Medicine

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    The author raises the question of whether physicians should disclose the stakes they have as researchers in persuading their patients to participate in clinical trials. In the course of giving informed consent, patients are rarely told that their doctors may have strong financial and professional interests in recruiting them as subjects, that pharmaceutical companies and the National Institutes of Health pay research centers and physicians well for completed patient studies, and that professional advancement and distinction depend on the amount of research done. Spiro believes controlled clinical trials are valuable, but argues that full disclosure of the benefits that physicians expect to achieve from their patients' willingness to serve as subjects will enhance the latters' freedom to decide on participation. (KIE abstract

    Synthetic and chromatographic study of the spiro-lactams and spiro-lactones based on a 9',10'-dihydro-(9,10)-ethanoanthracene Diels-Alder adduct. Application of flash vacuum thermolysis towards synthesis of exo-methylene lactones and lactams

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    Synthesis of a variety of spiro-lactams and spiro-lactones which are based on a 9\sp\prime,10\sp\prime-dihydro- (9,10) -ethanoanthracene Diels-Alder adduct has been performed. Control of relative stereochemistry at the C2 and C2, C3 carbons on the lactone ring during synthesis of the spiro-lactones has been observed and is dependent on the reaction temperature and the length of reaction time.The enantiomers of both the spiro-lactones and the spiro-lactams have been shown to separate on a chiral stationary phase derived from (R)-N-(3,5-dinitrobenzoyl)phenylglycine, (R)-CSP 1. Determination of the absolute stereochemistry at the spiro-junction of the most retained enantiomer on CSP 1 for both the spiro-lactams and spiro-lactones has been done using a variety of techniques including NMR, CD, CNDO/S-CI and force field calculations. In addition, NMR concentration studies using a soluble analogue of CSP 1 have been performed and aid in determining the important interactions responsible for enantiomer recognition. Models have been developed which describe the mode of enantiomer separation of these spiro adducts on (R)-CSP 1.Flash vacuum thermolysis of the spiro-lactam and spiro-lactone Diels-Alder adducts has allowed formation of a variety of exo-methylene lactams and exo-methylene lactones. In several examples, rearrangement of the exo to the more stable endo products is observed. Application of both the ability to resolve the enantiomers of a spiro-lactam precurser on CSP 1 and subsequent flash vacuum thermolysis affords an enantiomerically enriched exo-methylene lactam.Made available in DSpace on 2011-05-07T11:54:44Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 8916255.pdf: 4259962 bytes, checksum: 7b081c18813de4caff444f8d33833dc4 (MD5) Previous issue date: 1989Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding ([email protected]) on 2011-05-07T14:34:09Z Item is restricted indefinitely.Restriction data tranferred 2014-07-01T11:12:55-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permissionETDs are only available to UIUC Users without author permissionU of I Onl
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