bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: THE FORMATION OF PYRYLIUM ION SALTS FROM CYCLOPROPANES
Authors: EARNEST S. E. , BROWN D. B.
Published: March 2016

Dimethyl‐cyclopropan (I) (oder auch Olefine mit gleicher Zusammensetzung) liefern bei der Behandlung mit Chlorplatinsäure in Gegenwart von Acylierungsmitteln über (II) und (III) die Pyrylium‐Salze (IV) bzw. (V).
ChemInform Abstract: PROTECTION OF PRIMARY HYDROXYL GROUPS AS METHYLTHIOMETHYL ETHERS
Authors: COREY E. J. , BOCK M. G.
Published: March 2016

Durch Behandlung der Alkoholate mit Jodmethyl‐methylsulfid (Ia), das in situ aus der Chlorverbindung (Ib) und NaJ erhalten werden kann, erhält man aus entsprechenden Carbinolen (IIa)‐(IVa) die Äther (IIb)‐(IVb), deren Rückspaltung mit Mercuri‐chlorid oder mit Silbernitrat erfolgen kann.
ChemInform Abstract: HETEROCYCLISCHE SIEBENRING‐VERBINDUNGEN 16. MITT. SYNTHESE GEZIELT 3,5‐SUBSTITUIERTER 4‐PHENYL‐1‐BENZOTHIEPINE
Authors: HOFMANN HANS , HABERSTROH HANS‐JOACHIM , APPLER BERND , MEYER BERND , HERTERICH HELMUT
Published: March 2016

Der aus dem Dion (I) zugängliche Ketonäther (II) wird in die Derivate (III) bzw. (V) übergeführt, die thermisch zu den Naphthalinen (IV) bzw. (VI) desulfuriert werden.
ChemInform Abstract: OXIDATION OF SILICON‐SILICON AND SILICON‐HYDROGEN BONDS WITH MOLECULAR OXYGEN AND BIS(TRIMETHYLSILYL)PEROXIDE
Authors: TAMAO K. , KUMADA M. , TAKAHASHI T.
Published: March 2016

Die Oxidierbarkeit der Methylfluordisilane (I) und der 1,2‐Disilacycloalkane (II) bei Zimmertemperatur wird untersucht.
ChemInform Abstract: SILYLENE ADDITIONS TO CYCLOPENTADIENE AND 1,3‐CYCLOHEXADIENE, EVIDENCE FOR THE ADDITION MECHANISM
Authors: HWANG R.‐J. , CONLIN R. T. , GASPAR P. P.
Published: March 2016

Die Pyrolyse der Disilane (I) bzw. (II) führt über die Silylen‐Zwischenstufe (III) in Gegenwart von Cyclopentadien (IV) zu den Silacyclohexadienen (V), neben denen bei Dimethylsubstitution des Siliciums auch ein Isomeres (VIa) entsteht.
ChemInform Abstract: STEREOSPEZIFISCHE UEBERFUEHRUNG CHIRALER ACYCLISCHER TERTIAERER PHOSPHINSULFIDE IN DIE ENTSPRECHENDEN TERTIAEREN PHOSPHINOXIDE MIT DIMETHYLSULFOXID (DMSO)
Authors: LUCKENBACH REINER , KERN MANFRED
Published: March 2016

Die Überführung der Phosphinsulfide (I) in die Phosphinoxide (II) mit DMSO erfolgt unter vollständiger Inversion der Konfiguration am zentralen Phosphoratom.
ChemInform Abstract: LAMBDA(5)‐PHOSPHORINE DURCH UMWANDLUNG FUNKTIONELLER GRUPPEN AM PHOSPHORATOM
Authors: DIMROTH KARL , KIESELACK PETER
Published: March 2016

Die Äthoxycarbonylgruppe der Phosphorine (I) kann ohne Zerstörung des λ5‐ Ringsystems zu den Säuren (II) verseift werden, die beim Erwärmen die Verbindungen (III) liefern.
ChemInform Abstract: PREPARATION AND CONFIGURATIONAL ISOMERISM OF DITERTIARY STIBINE SULFIDES, (C6H5)(CH3)(S)SBCH2SB(CH3)(C6H5) AND ((C6H5(CH3)(S)SB)2(CH2)3)
Authors: SATO S.‐I. , MATSUMURA Y.
Published: March 2016

Durch Umsetzung der ditertiären Stibindichloride (I) bzw. (III) mit Natriumsulfid werden die ′asymmetrischen ditertiären Stibinsulfide (II) und (IV) hergestellt.
ChemInform Abstract: SELENIUM HETEROCYCLES PART 16, 1,2,3‐SELENADIAZOLYL DERIVATIVES OF POLYCYCLIC AROMATIC COMPOUNDS AND STEROIDS
Authors: GOLGOLAB H. , LALEZARI I.
Published: March 2016

Die beiden Semicarbazone (Ia), (Ib) reagieren mit Selendioxid (II) zu den Selenadiazolen (III), die thermisch zu den Äthinyl‐Verbindungen (IV) gespalten werden.
ChemInform Abstract: REAKTIONEN VON ALUMINIUMALKYLEN MIT CARBONYLVERBINDUNGEN 5. MITT. KETEN DURCH UMSETZUNG VON ALUMINIUMALKYLEN MIT ESSIGSAEUREANHYDRID
Authors: WARWEL S. , SCHIFFERS H.
Published: March 2016

Die Ausbeute an Keten (III) bei der Reaktion der Aluminiumalkyle (I) mit Essigsäureanhydrid (II) liegt zwischen 21% (Ia) und 46% (Id), kann aber durch Verwendung von Donatorkomplexen (IV) auf 80% (IVb) gesteigert werden.
ChemInform Abstract: DARSTELLUNG, STRUKTUR UND EINIGE REAKTIONEN VON TRIS‐(DIMETHYLAMINO)‐GALLAN
Authors: NOETH H. , KONRAD P.
Published: March 2016

Die Umsetzung von GaCla mit 2, 3 bzw. 4 Äquivalenten LiN(CH3 )2 führt zu den Gallanen (I), (II) bzw. (III).
ChemInform Abstract: DOUBLE ALKOXIDES OF ZIRCONIUM WITH ALKALINE EARTH METALS
Authors: GOVIL SARLA , MEHROTRA RAM C.
Published: March 2016

Durch Reaktion der Erdalkalimetalle in Isopropanol mit Zr‐isopropanolat in verschiedenen Molverhältnissen werden die flüchtigen Titelprodukte (I) und (II) erhalten.
ChemInform Abstract: ANHALTSPUNKTE FUER EINEN FUENFFACH KOORDINIERTEN KOMPLEX (R3SNX, LOESUNGSMITTEL) ALS UEBERGANGSZUSTAND BEI DER SUBSTITUTION DES HALOGENS DURCH EINE MAGNESIUMVERBINDUNG
Authors: LEQUAN M. , BESACE Y.
Published: March 2016

Die Reaktivität von Triphenylhalogenstannanen (I) gegenüber Grignard‐Verbindungen wird durch Komplexierung mit Phosphorsäuretris‐(dime thylamid) (=HMPT) (II) deutlich erhöht.
ChemInform Abstract: COORDINATION CHEMISTRY OF METHOXYDICHLOROOXOVANADIUM(V)
Authors: MILES STUART J. , WILKINS JOHN D.
Published: March 2016

Die Reaktion der aus V‐oxytrichlorid mit Methanol in Pentan dargestellten Titelverbindung mit N‐ und O‐Liganden führt zu den 1:1‐ und den 1:2‐Komplexen (Ia) und (Ib) bzw. (IIa) und (IIb).
ChemInform Abstract: THE CHEMISTRY OF METAL CARBONYL ANIONS PART 2, SYNTHESIS AND REACTIONS OF THE PENTACARBONYLMETALLATE DIANIONS OF CHROMIUM, MOLYBDENUM, AND TUNGSTEN WITH METALLIC MONOHALIDES
Authors: ELLIS J. E. , HENTGES S. G. , KALINA D. G. , HAGEN G. P.
Published: March 2016

Während mit Caesiumamalgam (IIa) aus den Carbonylen (I) die ionischen Verbindungen (III) entstehen, werden mit Natrium‐ oder Kaliumamalgam (IIb) bevorzugt die Derivate (IV) gebildet.
ChemInform Abstract: SCHIFF BASE COMPLEXES OF DIOXOURANIUM(VI) PART 1, DIOXOURANIUM(VI) COMPLEXES OF MONOBASIC BIDENTATE SCHIFF BASES
Authors: VIJAY R. G. , TANDON J. P.
Published: March 2016

Die durch Kondensation von Pentandion‐(2,4) oder o‐Hydroxyacetophenon mit entsprechenden primären Aminen erhaltenen Schiffschen Basen bilden mit Dioxo‐U(VI)‐ nitrat die Komplexe (I), die durch IR‐spektroskopische Daten, magnetische Suszeptibilitäten und Leitfähigkeitsmessungen charakterisiert werden.
ChemInform Abstract: KOMPLEXCHEMIE REAKTIVER ORGANISCHER VERBINDUNGEN 8. MITT. UEBER DIE BILDUNG VON MY‐CARBIN‐ UND PI‐ALKIN‐KOMPLEXEN AUS MERCURIERTEN DIAZOVERBINDUNGEN
Authors: HERRMANN W. A.
Published: March 2016

In siedendem Äther reagieren (I) und (II) zu einem Produkt (V) mit Alkoxycarbonylcarbin als neutralem Dreielektronen‐Brückenliganden und einer Verbindung (VI) mit einer Hg‐Br‐ und einer Acetylendicarbonsäureester‐Gruppe in cis‐Stellung (IR‐Spektren), in dem die Drehung des Alkin‐Liganden um seine Bindungsachse zum Zentralatom behindert ist (lH‐NMR‐Spektrum).
ChemInform Abstract: STEREOCHEMISTRY OF COMPLEXES OF MULTIDENTATE LIGANDS PART 5, STEREOSELECTIVE COBALT(III) ION COMPLEXES OF N,N′‐BIS(2‐S‐PYRROLIDYLMETHYL)‐TRANS‐R‐1,2‐CYCLOHEXANEDIAMINE
Authors: JUN MOO‐JIN , LIU CHUI FAN
Published: March 2016

Ausgehend vom S‐Prolin wird mit iso‐Butylchlorformiat und R‐Cyclohexandiamin das Produkt (II) erhalten, das durch Reduktionen den Titelliganden (III) in seiner SRS‐Konfiguration ergibt.
ChemInform Abstract: METAL COMPLEXES OF SULFUR‐CONTAINING PEPTIDES, NI(II) COMPLEX OF MERCAPTOPROPIONYLGLYCINE IN COMPARISON WITH GLYCYLGLYCINE
Authors: SUGIURA YUKIO , HIRAYAMA YOSHINOBU , TANAKA HISASHI , SAKURAI HIROMU
Published: March 2016

Der Ni‐Peptidkomplex (I) und ein 1:1‐Zn‐Komplex des α‐Mercaptopropionylglycins mit Bindung vom Schwefel und der Peptidcarbonylgruppe zum Metall wurden durch Reaktion von wässrigen Lösungen des Liganden mit den Metallchloriden.in Äthanol dargestellt, daneben entstehen auch 2:1‐Komplexe, die nicht näher charakterisiert sind.
ChemInform Abstract: NUCLEAR MAGNETIC RESONANCE STUDIES OF LEWIS ACID‐BASE INTERACTIONS PART 2, A CORRELATION BETWEEN ISOTROPIC CONTACT SHIFTS AND TAFT SIGMA(*) VALUES FOR SOME PYRIDINE BASE ADDUCTS OF NICKEL(II) BIS(O‐ALKYL DITHIOCARBONATES) AND BIS(BETA‐DIKETONATES)
Authors: LIM YAU Y. , CHUA KEE L.
Published: March 2016

Untersucht werden die Wechselwirkungen zwischen Pyridin, 4‐ und 3‐Methylpyridin und den O‐Alkyldithiocarbonaten des N i(II) mit den Alkylen: ‐(CH2 )2 ‐OCH3 , ‐(CH2),‐C6H5, ‐c, H5 und ‐CH2‐C(CH3)3 ,Untersuchteß‐Diketonate des Ni(II) sind: Acetylaceton, Dibenzoylmethan und Trifluoracetylnaphthoylmethan.
ChemInform Abstract: REVERSIBLE INSERTION OF NORBORNENE INTO A NICKEL‐METHALLYL BOND
Authors: GALAZZI M. C. , PORRI L. , VITULLI G.
Published: March 2016

Der bei Reaktion des Methallylkomplexes (I) mit Norbornen (II) gebildete Komplex (III) enthält wahrscheinlich n‐gebundenes Norbomen.
ChemInform Abstract: THE CLEAVAGE OF CARBON‐SULFUR AND CARBON‐NITROGEN BONDS LEADING TO RHODIUM‐THIOCARBOXAMIDO COMPLEXES
Authors: GAL A. W. , VAN DER PLOEG A. F. J. M. , VOLLENBROEK F. A. , BOSMAN W.
Published: March 2016

Die Umsetzung des Triphenylphosphinrhodium‐Komplexes (I) mit den Thiocarboxamid‐Derivaten (II) liefert unter Spaltung von Kohlenstoff‐Schwefel‐ und Kohlenstoff‐Stickstoff‐Bindungen die Thiocarboxamid‐Komplexe (III).
ChemInform Abstract: CHLORMETHYLIERUNG VON ARYLAMINO‐POLYCYCLO‐CHINONEN
Authors: PETROVA R. A. , SUSHKOVA V. N. , BORODKIN V. F.
Published: March 2016

Untersucht wird die Chlormethylierung von Brom‐toluylamino‐dibenzpyrenchinon und Dimethoxy‐brom‐toluylamino‐dibenzanthron.
ChemInform Abstract: NEW OXIDATION PRODUCTS OF TRYPTOPHAN
Authors: SAVIGE WALTER E.
Published: March 2016

Die Oxidation von L‐ oder DL‐Tryptophan (I) mit einem Mol Peressigsäure (II) in H2O bei (O‐5°C) gibt überwiegend ein Diastereoisomerengemisch des Pyrroloindols (III), während die Oxidation mit zwei oder drei Molen (II) hauptsächlich zu dem Formylkynureninn (IV) und den Diastereoisomeren des Benzoxazins (V) führt.
ChemInform Abstract: THE USE OF P‐JODOPHENYL((125)J)ISOTHIOCYANATE FOR DETERMINATION OF N‐TERMINAL AMINO ACIDS IN NANOMOLE QUANTITIES OF PROTEIN
Authors: BURRELL CHRISTOPHER J. , COOPER PETER D. , SWAN JOHN M.
Published: March 2016

Mit Hife von p‐[(125)J]Jodphenylisothiocyanat werden nach einer modifizierten Edman‐Reaktion die N‐terminalen Reste geringer Proteinmengen (2,5‐5 n Mol) bestimmt.
ChemInform Abstract: SYNTHESE UND EIGENSCHAFTEN EINIGER D‐GLUCOSE‐2,4‐DINITRO‐PHENYLAETHER
Authors: KLEMER ALMUTH , KLEEFELDT LOTHAR
Published: March 2016

Die Glucosederivate (I) bzw. (IV) werden mit dem Fluordinitrobenzol (II) zu den Äthern (III) bzw. (V) umgesetzt.
ChemInform Abstract: TOTAL SYNTHESIS OF MONOSACCHARIDES, SYNTHESIS OF METHYL DL‐PENTOPYRANOSIDES WITH ALPHA‐ AND BETA‐LYXO, BETA‐RIBO, ALPHA‐XYLO, AND ALPHA‐ARABINO CONFIGURATIONS FROM FURFURYL ALCOHOL
Authors: ACHMATOWICZ OSMAN JUN. , BUKOWSKI PAWEL
Published: March 2016

Die Titelverbindungen (IV), (Vb), (Va), (VIII) und (IXb) werden dargestellt.
ChemInform Abstract: TRAENENREIZSTOFFE ALS AKZEPTOREN FUER DIHYDROPYRIDINWASSERSTOFF
Authors: WALLENFELS K. , ERTEL W. , HOECKENDORF A. , RIESER J. , UEBERSCHAER K. H.
Published: March 2016

Tränenreizstoffe verschiedener Struktur [z.B. o‐Chlorbenzalmalonitril (CS), l‐Nitroolefine, cyclische Aldimine, Halogenverbindungen, Thiopropanal‐S‐oxid (Reizstoff der Zwiebel)) werden durch Wasserstoff‐Addition bzw. Halogensubstitution unter Verwendung von NADH‐Modellverbindungen (Dihydropyridinen) als Donatoren reduziert.
ChemInform Abstract: PERMEATION OF SIMPLE GASES THROUGH A POROUS MEDIUM
Authors: SCHNEIDER P.
Published: March 2016

Die Weber‐Gleichung wird zur Beschreibung einer Beziehung für die Durchlässigkeit nichtadsorbierter Gase durch ein poröses Medium mit bestimmter Porenverteilung herangezogen.
ChemInform Abstract: PENTAHALOGENO‐OXOURANATES(VI)
Authors: BAGNALL KENNETH W. , DU PREEZ JAN G. H. , GELLATLY BARRY J. , HOLLOWAY JOHN H.
Published: March 2016

Der Komplex [Ph4P][UOC15] (I) wird nach einer verbesserten Methode aus [Ph4 P]i[UO2 C14] und SOCl2 dargestellt und seine Chemie untersucht.
ChemInform Abstract: POLAROGRAPHIC REDUCTION OF 2‐AMINO‐4‐METHYL‐5‐ARYLAZOTHIAZOLES
Authors: MALIK WAHID U. , GOYAL R. N. , BHAVIKATTI M. R.
Published: March 2016

Die Thiazole (I) geben gut definierte, irreversible, diffusionskontrollierte Reduktionswellen für einen Zweielektronenumsatz.
ChemInform Abstract: ISOMERIZATION OF CYCLIC ALLENES
Authors: VAIDYANATHASWAMY R. , DEVAPRABHAKARA D.
Published: March 2016

Die Isomerisierung cyclischer Allene mit K‐tert.‐butylat in DMSO wird untersucht.
ChemInform Abstract: AZA‐WITTIG REARRANGEMENT OF (9‐LITHIO‐9‐FLUORENYL)‐ALLYL‐METHYL‐AMINE
Authors: REETZ M. T. , SCHINZER D.
Published: March 2016

Bei der Behandlung von Fluorenyl‐allyläther (Ia) mit Butyllithium erhält man über (IIa) glatt das Umlagerungsprodukt (IIIa), das auch aus dem entsprechenden Carbinol (IVa) entsteht.
ChemInform Abstract: PHOTOCHEMISTRY OF NITROSO DERIVATIVES IN SOLUTION PART 30, TEMPERATURE EFFECTS ON RADICAL ADDITIONS TO TERPENES AND REACTIONS OF 2‐AMMONIUM NITROSOALKANES
Authors: QUON H. H. , CHOW Y. L.
Published: March 2016

Die Photoaddition des Nitrosopiperidins (II) an dl‐Camphen (I) liefert das Oxim (V) als Hauptprodukt und daneben Dipiperidinomethan.
ChemInform Abstract: DYE‐SENSITIZED PHOTOOXYGENATION OF TERT.‐BUTYLPYRROLES
Authors: LIGHTNER D. A. , PAK C. S.
Published: March 2016

Die Photooxidation der isomeren tert.‐Butyl‐pyrrole, z.B. (I) und (VII),wird untersucht.
ChemInform Abstract: THE PHOTOCYCLOADDITION OF DICHLOROVINYLENE CARBONATE TO BENZENE AND NAPHTHALENE
Authors: SCHARF H. D. , LEISMANN H. , ERB W. , GAIDETZKA H. W. , ARETZ J.
Published: March 2016

Der Mechanismus der Photocycloaddition der Verbindung (I) an Benzol und Naphthalin wird diskutiert, die Struktur der entstehenden Produkte wird beschrieben.
ChemInform Abstract: THE REACTION OF LITHIUM TRIALKYLALKYNYLBORATES WITH PROPARGYL BROMIDE AND IODOACETONITRILE, A CONVENIENT SYNTHESIS OF FUNCTIONALLY SUBSTITUTED KETONES AND OLEFINS OF DEFINED CONFIGURATION
Authors: PELTER A. , GOULD K. J. , HARRISON C. R.
Published: March 2016

Aus den Li‐acetylenen (I) und den Boranen (II) entstehen die Addukte (III), die mit den aktivierten Halogenverbindungen (IV) zu (V) substituiert werden.
ChemInform Abstract: STRUKTUR UND EIGENSCHAFTEN VON NITROSOVERBINDUNGEN, SYNTHESE VON O‐NITROSOPHENOL‐ UND NITROSOANILIN‐SALZEN
Authors: BELYAEV E. YU. , GORNOSTAEV L. M. , PETROVA S. V.
Published: March 2016

Durch Merkurierungen der Alkylphenole (I) mit Hg‐acetat in Essigsäure‐Äthanol und Nitrosierungen der Hg‐Verbindungen (II) ohne vorherige Isolierung mit NaNO2 in acetatgepuffertem essigsaurem wäßrigen Medium lassen sich die o‐Nitrosophenol‐ Hg‐Komplexe (III) darstellen.
ChemInform Abstract: DIMETHYL SULFOXIDE‐TRIFLUOROACETIC ANHYDRIDE, A NEW AND EFFICIENT REAGENT FOR THE PREPARATION OF IMINOSULFURANES
Authors: SHARMA A. K. , KU T. , DAWSON A. D. , SWERN D.
Published: March 2016

Dimethylsulfoxid (I) kann unter vorsichtigen Bedingungen mit Trifluoressigsäureanhydrid (II) zu einem Salz (III) umgesetzt werden, aus dem mit aromatischen A′minen (IV) die Iminosulfurane (V) gebildet werden.
ChemInform Abstract: ACID‐CATALYSED REACTIONS OF EPOXIDES WITH DIMETHYL SULFOXIDE
Authors: SANTOSUSSO T. M. , SWERN D.
Published: March 2016

Styrol‐oxid (Ia) und p‐Nitro‐styroloxid (Ib) reagieren mit Dimethyl‐sulfoxid (II) zu Spaltprodukten (IIIa), (IIIb); daneben werden Isomere der Art (IV) erhalten.
ChemInform Abstract: ONIUM‐BETAINE DES 1,3‐DIPHENYL‐2H‐CYCLOPENTA(L)PHENANTHRENS
Authors: KREITSBERGA YA. N. , NEILAND O. YA. , KAMPAR V. E.
Published: March 2016

Durch Reduktionen des Ketons (I), zunächst mit Zn in siedender Essigsäure, dann mit NaBH4 insiedendem Dioxan, wird der Alkohol (II) dargestellt.
ChemInform Abstract: SYNTHESIS OF 5‐NITRO‐2‐FURONIC ACID
Authors: KRAPIVIN G. D. , BADOVSKAYA L. A. , KUL'NEVICH V. G.
Published: March 2016

Die Oxidation des Nitrofurfurals (I) mit Wasserstoffperoxid führt je nach der Konzentration des angewandten Wasserstoffperoxids zu der Carbonsäure (II) oder dem Oxyhydroperoxid (III).
ChemInform Abstract: OVERCROWED MOLECUES PART 12, THERMAL AND PHOTOCHEMICAL REACTIONS OF (2Z,3Z)‐ AND (2Z,3E)‐BENZYLIDENE‐2,3‐DIHYDRO‐3‐MESITYL(PHENYL)‐METHYLENEBENZOFURAN
Authors: HASTINGS JOHN S. , HELLER HARRY G. , SALISBURY KINGSLEY
Published: March 2016

Das Keton (I) setzt sich mit dem Keten (II) bei 56°C zu den Benzofuranen (III) und (IV) (4: 1) um.
ChemInform Abstract: SYNTHESIS OF SUBSTITUTED 2‐AMINO‐3‐CYANOPYRROLES
Authors: SHVEDOV V. I. , MEZENTSEVA M. V. , GRINEV A. N.
Published: March 2016

Die bei der Umsetzung der Ketone (I) mit Äthylformiat (II) in Gegenwart von Natriumäthylat entstehenden Formylketon‐Derivate (III) und (IV) werden mit Phenyldiazoniumchlorid (V) zu den Monophenylhydrazonen (VI) und (VII) kondensiert.
ChemInform Abstract: STUDIES ON ACTIVITY‐STRUCTURE RELATIONSHIPS PART 1, MUSCARINIC ACTIVITY AND CONFORMATIONAL FEATURES IN AMMONIUM‐SUBSTITUTED 1,3‐DIOXOLANES AND 1,3‐DIOXANES
Authors: ANTEUNIS MARC J. O. , VAN CAUWENBERGHE ROBERT , VALCKX LUDO , VAN BEVER WILLEM F. M. , VAN NUETEN JAN M.
Published: March 2016

Die Muscarin‐Aktivitäten der Dioxolane (II) (4 Isomere), (III), (IVa) und (IVb) (jeweils 2 Isomere) sowie der Dioxane (Va), (Vb) (2 Isomere), (VIa), (V‐Ib), (VIIa), (VIIb) (2 Isomere), (VIII), (IXa), (IXb) (2 Isomere), (Xa) und (Xb) (2 Isomere), deren Darstellung kürzlich beschrieben worden ist, werden bestimmt (Tabelle).
ChemInform Abstract: MANNICH BASES AND IODOMETHYLATE OF SUBSTITUTED 6‐(FURYL‐2)IMIDAZO(2,1‐B)THIAZOLES
Authors: SALDABOL N. O. , ZELIGMAN L. L. , RITEVSKAYA L. A.
Published: March 2016

Die Mannich‐Reaktion der Furyl‐imidazothiazole (I) liefert je nach den Molverhältnissen die Verbindungen (IV) und (V).
ChemInform Abstract: THE CHEMISTRY OF 1,2,5‐THIADIAZOLES PART 3, (1,2,5)THIADIAZOLO(3,4‐C)(1,2,5)THIADIAZOLE
Authors: KOMIN A. P. , STREET R. W. , CARMACK M.
Published: March 2016

Aus dem Diamino‐thiadiazol‐dioxid (I) entsteht mit Schwefelmonochlorid oder Schwefeldichlorid in DMF das Thiadiazolo‐thiadiazol (II), das auch aus dem Diamino‐thiadiazol (III) oder aus Oxamiddioxim (IV) mit ähnlichen Reagentien erhalten wird.
ChemInform Abstract: DIHYDROPYRAN‐DERIVATE 3. MITT. 2‐(PROPINYLOXYALKOXY)‐3,4‐DIHYDROPYRANE UND IHRE REAKTIONEN
Authors: LAVROV V. I. , ATAVIN A. S. , STANKEVICH V. K. , SKOROBOGATOVA V. I. , PARSHINA L. N.
Published: March 2016

Durch Metallierungen der Hydroxyalkoxydihydropyrane (I) mit Na (in Diäthyl‐ äther) und Kondensationen der entstehenden Alkoholate mit Propargylchlorid (in siedendem Diäthyläther) lassen sich die Propargyloxyalkoxydihydropyrane (II) darstellen.
ChemInform Abstract: SYNTHESIS OF CYCLIC SULPHIDES PART 7, SYNTHESIS OF 3‐PHENYLTHIACYCLOHEXANE AND 2‐METHYL‐4‐PHENYL‐THIACYCLOPENTANE
Authors: KRIVONOGOV V. P. , DRONOV V. I. , POKONESHCHIKOVA N. K.
Published: March 2016

Das aus dem Episulfid (I) und Allylmagnesiumbromid (II) hergestellte Mercaptan (III) cyclisiert bei UV‐Belichtung zu einem Gemisch von Thiacy clohexan (IV) und Thiacyclopentan (V).
ChemInform Abstract: 2‐STYRYL‐4H‐1,3‐BENZOXAZINE‐4‐ONIUM SALTS
Authors: RYABUKHIN YU. I. , MEZHERITSKII V. V. , KARPENKO V. D. , DOROFEENKO G. N.
Published: March 2016

Die Kondensation der Benzoxazinoniumsalze (I) mit aromatischen Aldehyden (II) in Acetanhydrid/Eisessig liefert 2‐Styrylbenzoxazinoniumsalze (III).
ChemInform Abstract: AGENTS ACTING ON CENTRAL NERVOUS SYSTEM PART 23, 2‐SUBSTITUTED 1,2,3,4,6,7,12,12A‐OCTAHYDROPYRAZINO(2,1‐B)(3)BENZAZEPINES AND 3‐SUBSTITUTED 1,3,4,4A,5,6,11‐OCTAHYDROPYRAZINO(1,2‐B)(2)BENZAZEPINES
Authors: DIXIT V. M. , KHANNA J. M. , ANAND NITYA , CHAK I. M.
Published: March 2016

Ausgehend von den Lactamen (Ia) bzw. (Ib) werden über die Lactilnäther (II) und die Nitroverbindungen (III) die Amine (IVa) bzw. (IVb) dargestellt, die mit dem Oxalsäureester (V) zu den Heterocyclen (VIa) bzw. (VIb) cyclisiert werden.
ChemInform Abstract: REACTIONS OF ALKALI HYDRIDES WITH 2‐METHOXYETHYL BORATE, SYNTHESIS OF SODIUM MONOHYDRIDO‐TRIS(2‐METHOXYETHOXY)‐BORATE
Authors: SOCHOR P. , KADLECOVA H. , STROUF O.
Published: March 2016

Die Alkalimetallhydride (I) reagieren mit dem Borat (II) unter Bildung der Monohydridoborate (III), die unter den Reaktionsbedingungen in die Borate (IV) und die Hydridoborate (V) disproportionieren.
ChemInform Abstract: CATALYSIS BY METAL COMPLEXES PART 31, HYDROSILYLATION OF 1,3‐BUTADIENE WITH ALKYL‐ AND ALKOXYSILANES CATALYSED WITH NI(II) AND NI(0) COMPOUNDS
Authors: CAPKA M. , HETFLEJS J.
Published: March 2016

Die Hydrosilylierung von Butadien‐(1,3) an Ni‐Katalysatoren, wie z.B. Bis(cycloocta‐ dien)nickel, mit den Silanen (II) verläuft im Unterschied zu der Hydrosilylierung an Pd‐Komplexen unter bevorzugter Bildung der cis‐Silylbutene (III), neben denen nur geringe Mengen an Octadienen, wie (IV), entstehen.
ChemInform Abstract: UMSETZUNG DES TETRAMETHYL‐DIPHOSPHINDISULFIDS MIT CARBONSAEURECHLORIDEN UND DIE CHEMISCHE POLARISIERUNG DES PHOSPHORS IN SEINEN REAKTIONSPRODUKTEN
Authors: PUDOVIK A. N. , ROMANOV G. V. , LAPIN A. A. , GOL'DFARB E. I.
Published: March 2016

Bei der Photolyse des Gemisches aus (I) und (II) zu (III) (Hauptprodukt) und (IV) beobachtet man eine chemische Polarisierung des Phosphors (III): δp‐88 m.d.; (IV): δp‐63 m.d.
ChemInform Abstract: THE SYNTHESIS AND CHARACTERIZATION OF SOME (AMINOMETHYL)TRIALKYL‐ AND (AMINOMETHYL)TRIPHENYL‐TINS
Authors: ABEL E. W. , ROWLEY R. F.
Published: March 2016

J odmethyltrimethylzinn (I) wird mit verschiedenen Aminen (II) zu Aminomethylstannanen (III) umgesetzt.
ChemInform Abstract: REARRANGED STERENES IN A SHALE. OCCURRENCE AND SIMULATED FORMATION
Authors: RUBINSTEIN IAN , SIESKIND ODETTE , ALBRECHT PIERRE
Published: March 2016

Aus dem Extrakt eines bituminösen Schiefers werden das S‐ und das R‐Epimere des Cholestens (II) erhalten, sowie weitere kernmethylierte und seitenkettenalkylierte Homologe.
ChemInform Abstract: EXPERIMENTS ON THE SYNTHESIS OF PYRAZINE NUCLEOSIDES
Authors: CHEESEMAN GORDON W. H. , FREESTONE ALAN J. , GODWIN ROBERT A. , HOUGH THOMAS L.
Published: March 2016

Reaktion des α‐D‐Glucopyranosylbromids (I) mit dem Bis‐silyloxy‐pyrazin (II) ergibt das Bis‐(β‐D‐glucopyranosyl)‐pyrazindion (III).
ChemInform Abstract: SYNTHESIS OF C NUCLEOSIDES PART 10, STRUCTURAL ANALOGS OF FORMYCIN B
Authors: HUYNH‐DINH T. , KOLB A. , GOUYETTE C. , IGOLEN J. , TRAN‐DINH S.
Published: March 2016

4‐Amino‐3‐carbäthoxy‐pyrazol (I) kondensiert mit den Thiobenzimidaten (II) zu den Kondensationsprodukten (III).
The molecular characteristics of colonic neoplasms in serrated polyposis: a systematic review and meta‐analysis
Authors: He Emily Y. , Wyld Lucy , Sloane Mathew A. , Canfell Karen , Ward Robyn L.
Published: March 2016

Serrated polyposis is a rare disorder characterised by the presence of multiple serrated polyps in the large intestine, and an increased personal and familial risk of colorectal cancer. Knowledge of the molecular characteristics of colonic lesions which develop in this syndrome is fragmented, making it difficult to understand the underlying genetic basis of this condition. We conducted a systematic review and meta‐analysis of all studies which evaluated the molecular characteristics of colorectal neoplasms found in individuals with serrated polyposis. We identified 4561 potentially relevant studies, but due to a lack of consensus in the reporting of findings, only fourteen studies were able to be included in the meta‐analysis. BRAF mutation was found in 73% (95% CI 65–80%) of serrated polyps, 0% (95% CI 0–3%) of conventional adenomas and 49% (95%CI 33–64%) of colorectal cancers. In contrast, KRAS mutation was present in 8% (95% CI 5–11%) of serrated polyps, 3% (95% CI 0–13%) of conventional adenomas and 6% (95% CI 0–13%) of colorectal cancers. Absence of MLH1 immunostaining was found in 3% (95% CI 0–10%) of serrated polyps and 53% (95% CI 36–71%) of colorectal cancers. Overall, microsatellite instability was found in 40% (95% CI 18–64%) of colorectal cancers arising in the setting of serrated polyposis. Our results indicate that diverse molecular pathways are likely to contribute to the increased predisposition for colorectal cancer in individuals with serrated polyposis. We also propose a set of minimum standards for the reporting of future research in serrated polyposis as this is a rare syndrome and collation of research findings from different centres will be essential to identify the molecular mechanisms involved in the pathogenesis of this condition.
Fixation patterns, not clinical diagnosis, predict body size over‐estimation in eating disordered women and healthy controls
Authors: Cornelissen Katri K. , Cornelissen Piers L. , Hancock Peter J. B. , Tovée Martin J.
Published: March 2016

Objective

A core feature of anorexia nervosa (AN) is an over‐estimation of body size. Women with AN have a different pattern of eye‐movements when judging bodies, but it is unclear whether this is specific to their diagnosis or whether it is found in anyone over‐estimating body size.

Method

To address this question, we compared the eye movement patterns from three participant groups while they carried out a body size estimation task: (i) 20 women with recovering/recovered anorexia (rAN) who had concerns about body shape and weight and who over‐estimated body size, (ii) 20 healthy controls who had normative levels of concern about body shape and who estimated body size accurately (iii) 20 healthy controls who had normative levels of concern about body shape but who did over‐estimate body size.

Results

Comparisons between the three groups showed that: (i) accurate body size estimators tended to look more in the waist region, and this was independent of clinical diagnosis; (ii) there is a pattern of looking at images of bodies, particularly viewing the upper parts of the torso and face, which is specific to participants with rAN but which is independent of accuracy in body size estimation.

Discussion

Since the over‐estimating controls did not share the same body image concerns that women with rAN report, their over‐estimation cannot be explained by attitudinal concerns about body shape and weight. These results suggest that a distributed fixation pattern is associated with over‐estimation of body size and should be addressed in treatment programs. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2016; 49:507–518).
Obesity in early adulthood predicts knee pain and walking difficulties among men: A life course study
Authors: Frilander H. , Viikari‐Juntura E. , Heliövaara M. , Mutanen P. , Mattila V.M. , Solovieva S.
Published: March 2016

Background

Few studies have addressed the role of obesity in young adulthood in knee problems later in life. We assessed the associations of overweight/obesity with knee pain and functional limitations of the knee across the life course.

Methods

Military health records from 1967 to 2000 (baseline) were searched for 18‐ to 50‐year‐old Finnish men (n = 1913) who participated in the Health 2000 Study (follow‐up). Visits to health care were followed during service. Height and weight were measured at baseline and follow‐up and waist circumference at follow‐up. Weight was inquired at follow‐up for ages of 20, 30, 40 and 50 years, if applicable. Life course body mass index (BMI) was calculated. One‐month knee pain and functional limitations (walking difficulties and limping) due to knee problems were enquired with interview at follow‐up. Cox regression model, logistic regression and trajectory analysis were applied.

Results

Body mass index at the age of 20 increased the risk of unilateral knee pain by 38% and functional limitations by 27% for one standard deviation increment of BMI, respectively. One‐unit increment of Z‐score of life course BMI increased knee pain by 32%. Development of severe obesity during the follow‐up increased the risk of knee pain by 80% and functional limitations by 93%. The effect of obesity on functional limitations was partly mediated by traumatic knee problems during military service.

Conclusions

Reducing overweight already in adolescence and avoiding further weight gain during life course may prevent knee pain and associated disability.

What does this study add?

BMI at the age of 20 increases the likelihood of knee pain and functional limitations of the knee later in life.

Development of severe obesity in adulthood increases the risk of knee pain by 80% and functional limitations by more than 90%.

Both general and abdominal obesity are associated with knee pain, associations being stronger for general obesity.
Tin Oxide Light‐Scattering Layer for Titania Photoanodes in Dye‐Sensitized Solar Cells
Authors: Batmunkh Munkhbayar , Dadkhah Mahnaz , Shearer Cameron J. , Biggs Mark J. , Shapter Joseph G.
Published: March 2016

High‐performance dye‐sensitized solar cell (DSSC) devices rely on photoanodes that possess excellent light‐harvesting capabilities and high surface areas for sufficient dye adsorption. In this work, morphologically controlled SnO2 microstructures were synthesized and used as an efficient light‐backscattering layer on top of a nanocrystalline TiO2 layer to prepare a double‐layered photoanode. By optimizing the thickness of both the TiO2 bottom layer and the SnO2 top layer, a high power conversion efficiency (PCE) of 7.8 % was achieved, an enhancement of approximately 38 % in the efficiency compared with that of a nanocrystalline TiO2‐only photoanode (5.6 %). We attribute this efficiency improvement to the superior light‐backscattering capability of the SnO2 microstructures.
Efficient neural network modeling of reconfigurable microstrip patch antenna through knowledge‐based three‐step strategy
Authors: Simsek M.
Published: March 2016

Artificial neural network (ANN) provides an efficient modeling technique based on input–output data obtained from an engineering problem. Highly nonlinear and complex relationships can be formed by ANN because of its nonlinear nature and representing knowledge at interconnection weights. If an ANN model is not sufficient in respect to the accuracy and time consumption, the knowledge based on design experience can be embedded into the modeling process. This knowledge reduces the complexity of the nonlinear input–output relationships; therefore, the knowledge embedded ANN can be formed easily compared with the conventional ANN model. Three‐step modeling strategy generates the initial knowledge via the conventional ANN modeling and consists of three sequential and also discrete training processes exploiting the knowledge‐based methods such as prior knowledge input and prior knowledge input with difference. The latter step improves the accuracy of the former step, and three‐step modeling provides more accuracy than conventional ANN modeling. The efficiency of three‐step modeling strategy is demonstrated on two data sets, which are obtained by the reconfigurable microstrip patch antenna design problem. The different number of neurons and ANN structures is handled for the comparison as well. In addition, ANN modeling is formed by MATLAB m‐file through neural network toolbox to reveal the efficiency of knowledge‐based three‐step modeling strategy. Copyright © 2016 John Wiley & Sons, Ltd.
Spatio‐temporal dynamics in nondiffractive Bessel ultrafast laser nanoscale volume structuring
Authors: Velpula P. K. , Bhuyan M. K. , Courvoisier F. , Zhang H. , Colombier J. P. , Stoian R.
Published: March 2016

Nondiffractive ultrafast optical beams with quasi‐stationary characteristics enable new regimes and scales in light‐matter interactions. We discuss the action of ultrashort Bessel laser beams in bulk fused silica, emphasizing excitation dynamics with energy localization beyond diffraction limit. We shed light on relaxation channels leading to one‐dimensional structures with nanoscale sections and morphologies ranging from densified matter to nanosized cavities. Space‐ and time‐resolved absorption and phase‐contrast microscopy reveals two main carrier relaxation paths. Fast exciton trapping in self‐induced matrix deformations results in positive index contrast driven by swift accumulation of non‐bridging oxygen hole centers and defect‐driven structural rearrangements. High excitation densities determine thermomechanical paths, with onset of phase transitions and the release of pressure waves. High‐aspect‐ratio nanosized channels are thus created via rarefaction and liquid cavitation, accompanied by molecular decomposition and generation of oxygen deficiency. The characteristic electronic relaxation identifies the nature of structural transitions up to the onset of phase transformation. Temporal pulse dispersion regulation allows driving unique carrier dynamics with precise control over energy deposition down to the 100 nm scale. Extreme high‐aspect‐ratio uniform void structures can thus be fabricated in conditions of sub‐micron transverse light confinement.

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Dielectric studies of al nanoparticle reinforced epoxy resin composites
Authors: Wang Zijun , Zhou Wenying , Sui Xuezhen , Dong Lina , Cai Huiwu , Zuo Jing , Liu Xiangrong , Chen Qingguo
Published: March 2016

Epoxy (EP) resin based nanocomposites with aluminum (Al) nanoparticles were prepared by solution method, with ultrasonic assisted dispersion followed by hot‐pressing methods. The dielectric permittivity, loss tangent, conductivity, and electric modulus of the nanocomposites were investigated by dielectric spectroscopy measurements in a wide frequency range from 1 to 107 Hz at temperatures from −20°C to 200°C. For all samples, the dielectric permittivity, dissipation factor, and electric conductivity increase with increasing temperature due to enhanced chain mobility above glass transition temperature (Tg). Broadband dielectric spectroscopy shows the multiple dielectric processes in the Al/epoxy nanocomposites corresponding to interfacial polarization (IP), α‐relaxation, and ionic conductivity, respectively. IP is detected at low frequencies and high temperatures. A primary α‐relaxation process is found at near Tg at the middle frequencies and the intermediate dipolar effect (IDE) is presented at high frequencies. The mechanisms responsible for dielectric relaxation, conductivity process, and electric modulus response have been discussed in detail. POLYM. COMPOS., 39:887–894, 2018. © 2016 Society of Plastics Engineers
Toughening effect of poly(methyl methacrylate) on an immiscible poly(vinylidene fluoride)/polylactide blend
Authors: Yang Jing‐hui , Feng Chen‐xia , Chen Hai‐ming , Zhang Nan , Huang Ting , Wang Yong
Published: March 2016

In this work, a mutually miscible third polymer, poly(methyl methacrylate) (PMMA), was incorporated into an immiscible poly(vinylidene fluoride)/polylactide (PVDF/PLA) blend (weight ratio 70:30). It was found that incorporation of PMMA in an appropriate amount (30–60 wt%) induced a marked improvement in fracture toughness. A five times enlargement of the elongation at break can be achieved by introducing 30 wt% PMMA. In order to understand the underlying toughening mechanism, SEM, dynamic mechanical analysis (DMA), XRD and DSC were applied to study the variations in morphology, the interaction between the three components and the crystallization behavior. SEM micrographs showed that the PMMA preferred to locate at the interface of PVDF and PLA, which was attributed to the mutual miscibility of PVDF with PMMA and PLA. Furthermore, a variety of thermal characteristics such as Tg and Tm induced by the entanglement of PVDF, PMMA and PLA at the interface were illustrated in DMA and DSC curves. Obviously, the interface consisting of the entanglement of PVDF, PLA and PMMA acted as a linkage to improve interfacial adhesion, which was regarded as the main toughening mechanism. This work provides a potential strategy to realize the interfacial enhancement of an immiscible blend via the incorporation of a mutually miscible third polymer. © 2016 Society of Chemical Industry
Tannic acid and cholesterol–dopamine as building blocks in composite coatings for substrate‐mediated drug delivery
Authors: Zhang Yan , Baekgaard‐Laursen Marie , Mouritzen Sidsel A , Lynge Martin E , Schattling Philipp S , Danial Maarten , Postma Almar , Städler Brigitte
Published: March 2016

Composite coatings are considered a promising approach to tailor the biointerface between a (implantable) biomaterial and adhering/surrounding cells or tissue. In this context, composite coatings assembled using a polymer matrix with embedded drug deposits are particularly interesting due to the advanced control over cargo loading, retention and release. Herein, we compare the assembly of such films consisting of various types of liposomes as subunits within a polymer film of either polydopamine (PDA) or, for the first time, tannic acid (TA) as an alternative. It is found that TA is a suitable capping layer for liposome‐coated substrates which allows for post‐modification. The composite coatings are suitable for supporting hepatocyte adhesion depending on the terminating polymer layer. Furthermore, incorporation of cholesterol–dopamine (Ch‐DA) conjugates into the zwitterionic liposomes increases the numbers of deposited subunits. Finally, cytotoxic paclitaxel is loaded into the liposomes and delivered to the adhering hepatocytes. The capability of reducing hepatocyte adhesion to the composite coating varied. Composite coatings consisting of negatively charged liposomes with Ch‐DA and a PDA capping layer are found to be most efficient after 24 and 48 h. Taken together, this fundamental comparison of different composite coatings illustrates the excellent opportunities to engineer the biological response towards the application in mind. © 2016 Society of Chemical Industry
Higher‐dimensional gauge theories from string theory
Authors: Tomasiello Alessandro
Published: March 2016

We review some recent developments regarding supersymmetric field theories in six and five dimensions. In particular, we will describe the classification of supersymmetric six‐dimensional theories with a holographic IIA dual; they are “linear quivers” consisting of chains of many SU (or SO/Sp) gauge groups connected by hypermultiplets and tensor multiplets. We will also describe the wider classification of supersymmetric six‐dimensional theories that can be engineered in F‐theory; these are also chains, but they include exceptional gauge groups and copies of a more exotic “E‐string” theory with a single tensor and E8 flavor symmetry. Finally we discuss some properties of these theories under compactification to lower dimensions.
Understanding taxanes in prostate cancer; importance of intratumoral drug accumulation
Authors: de Morrée Ellen , van Soest Robert , Aghai Ashraf , de Ridder Corrina , de Bruijn Peter , Ghobadi Moghaddam‐Helmantel Inge , Burger Herman , Mathijssen Ron , Wiemer Erik , de Wit Ronald , van Weerden Wytske
Published: March 2016

BACKGROUND

Resistance to docetaxel is common in metastatic castration‐resistant prostate cancer (mCRPC) and may be caused by sub‐therapeutic intratumoral drug concentrations. Cabazitaxel demonstrated survival benefit in docetaxel‐pretreated and docetaxel‐refractory patients. In this study, we investigated whether the superior antitumor activity of cabazitaxel in mCRPC is explained by higher intratumoral cabazitaxel levels. Since recent studies suggest a reduced efficacy of docetaxel following treatment with novel androgen receptor (AR)‐targeted agents, we also investigated taxane efficacy in an enzalutamide‐resistant tumor model.

METHODS

Intratumoral concentrations of docetaxel and cabazitaxel were correlated with antitumor activity in docetaxel‐naïve, docetaxel‐resistant, and enzalutamide‐resistant patient‐derived xenografts (PDXs) of prostate cancer.

RESULTS

Intratumoral drug levels were negatively related to intrinsic and acquired resistance to docetaxel. Also, the observed stronger antitumor activity of cabazitaxel was associated with increased cumulative exposure and higher intratumoral of cabazitaxel concentrations in all PDXs.

CONCLUSIONS

The superior antitumor activity of cabazitaxel in docetaxel‐ and enzalutamide‐resistant tumors can be partly attributed to higher intratumoral drug concentrations. Especially for patients who are intrinsically resistant to docetaxel resulting from suboptimal intratumoral docetaxel concentrations, cabazitaxel may be the preferred chemotherapeutic agent. Prostate 76:927–936, 2016. © 2016 Wiley Periodicals, Inc.
Low‐temperature grown indium oxide nanowire‐based antireflection coatings for multi‐crystalline silicon solar cells
Authors: Wang Yu‐Cian , Chen Chih‐Yao , Kuo Cheng‐Wen , Kuan Ta‐Ming , Yu Cheng‐Yeh , Chen I‐Chen
Published: March 2016

Light harvesting by indium oxide nanowires (InO NWs) as an antireflection layer on multi‐crystalline silicon (mc‐Si) solar cells has been investigated. The low‐temperature growth of InO NWs was performed in electron cyclotron resonance (ECR) plasma with an O2–Ar system using indium nanocrystals as seed particles via the self‐catalyzed growth mechanism. The size‐dependence of antireflection properties of InO NWs was studied. A considerable enhancement in short‐circuit current (from 35.39 to 38.33 mA cm−2) without deterioration of other performance parameters is observed for mc‐Si solar cells coated with InO NWs.
Sensitivity to censored‐at‐random assumption in the analysis of time‐to‐event endpoints
Authors: Lipkovich Ilya , Ratitch Bohdana , O'Kelly Michael
Published: March 2016

Over the past years, significant progress has been made in developing statistically rigorous methods to implement clinically interpretable sensitivity analyses for assumptions about the missingness mechanism in clinical trials for continuous and (to a lesser extent) for binary or categorical endpoints. Studies with time‐to‐event outcomes have received much less attention. However, such studies can be similarly challenged with respect to the robustness and integrity of primary analysis conclusions when a substantial number of subjects withdraw from treatment prematurely prior to experiencing an event of interest. We discuss how the methods that are widely used for primary analyses of time‐to‐event outcomes could be extended in a clinically meaningful and interpretable way to stress‐test the assumption of ignorable censoring. We focus on a ‘tipping point’ approach, the objective of which is to postulate sensitivity parameters with a clear clinical interpretation and to identify a setting of these parameters unfavorable enough towards the experimental treatment to nullify a conclusion that was favorable to that treatment. Robustness of primary analysis results can then be assessed based on clinical plausibility of the scenario represented by the tipping point. We study several approaches for conducting such analyses based on multiple imputation using parametric, semi‐parametric, and non‐parametric imputation models and evaluate their operating characteristics via simulation. We argue that these methods are valuable tools for sensitivity analyses of time‐to‐event data and conclude that the method based on piecewise exponential imputation model of survival has some advantages over other methods studied here. Copyright © 2016 John Wiley & Sons, Ltd.
Estimands: discussion points from the PSI estimands and sensitivity expert group
Authors: Phillips Alan , Abellan‐Andres Juan , Soren Andersen , Bretz Frank , Fletcher Chrissie , France Lesley , Garrett Andrew , Harris Raymond , Kjaer Magnus , Keene Oliver , Morgan David , O'Kelly Michael , Roger James
Published: March 2016

ICH E9 Statistical Principles for Clinical Trials was issued in 1998. In October 2014, an addendum to ICH E9 was proposed relating to estimands and sensitivity analyses. In preparation for the release of the addendum, Statisticians in the Pharmaceutical Industry held a 1‐day expert group meeting in February 2015. Topics debated included definition, development, implementation, education and communication challenges associated with estimands and sensitivity analyses. The topic of estimands is an important and relatively new one in clinical development. A clear message from the meeting was that estimands bridge the gap between study objectives and statistical methods. When defining estimands, an iterative process linking trial objectives, estimands, trial design, statistical and sensitivity analysis needs to be established. Each objective should have at least one distinct estimand, supported by sensitivity analyses. Because clinical trials are multi‐faceted and expensive, it is unrealistic to restrict a study to a single objective and associated estimand. The actual set of estimands and sensitivity analyses for a study will depend on the study objectives, the disease setting and the needs of the various stakeholders. Copyright © 2016 John Wiley & Sons, Ltd.
Temperature auto‐correlation and spectra functions in low‐wind meandering conditions
Authors: Mortarini L. , Maldaner S. , Moor L. P. , Stefanello M. B. , Acevedo O. , Degrazia G. , Anfossi D.
Published: March 2016

Eulerian low‐wind temperature statistics are investigated through the analysis of sonic anemometer observations gathered in two experimental campaigns, the Urban Turbulent Project in Northern Italy and the Large‐Scale Biosphere‐Atmosphere Experiment in Amazonia (Brazil). The observed auto‐correlations and spectra functions are tested with the theoretical relationships previously proposed for the horizontal velocity components in low wind speed conditions. The comparison showed that the temperature field, similarly to the horizontal velocity field, presents a characteristic oscillatory behaviour with a distinct isolated spectrum peak frequency due to the wind meandering. The ratio between this frequency and the one associated to the horizontal velocity components is close to one. This, together with the similarity between the temperature and velocity spectra and auto‐correlation functions, suggests that a dynamical link between temperature and velocity oscillations exists.
A Central Line Care Maintenance Bundle for the Prevention of Central Line–Associated Bloodstream Infection in Non–Intensive Care Unit Settings
Authors: O’Neil Caroline , Ball Kelly , Wood Helen , McMullen Kathleen , Kremer Pamala , Jafarzadeh S. Reza , Fraser Victoria , Warren David
Published: March 2016

OBJECTIVE

To evaluate a central line care maintenance bundle to reduce central line–associated bloodstream infection (CLABSI) in non–intensive care unit settings.

DESIGN

Before-after trial with 12-month follow-up period.

SETTING

A 1,250-bed teaching hospital.

PARTICIPANTS

Patients with central lines on 8 general medicine wards. Four wards received the intervention and 4 served as controls.

INTERVENTION

A multifaceted catheter care maintenance bundle consisting of educational programs for nurses, update of hospital policies, visual aids, a competency assessment, process monitoring, regular progress reports, and consolidation of supplies necessary for catheter maintenance.

RESULTS

Data were collected for 25,542 catheter-days including 43 CLABSI (rate, 1.68 per 1,000 catheter-days) and 4,012 catheter dressing observations. Following the intervention, a 2.5% monthly decrease in the CLABSI incidence density was observed on intervention floors but this was not statistically significant (95% CI, −5.3% to 0.4%). On control floors, there was a smaller but marginally significant decrease in CLABSI incidence during the study (change in monthly rate, −1.1%; 95% CI, −2.1% to −0.1%). Implementation of the bundle was associated with improvement in catheter dressing compliance on intervention wards (78.8% compliance before intervention vs 87.9% during intervention/follow-up; P<.001) but improvement was also observed on control wards (84.9% compliance before intervention vs 90.9% during intervention/follow-up; P=.001).

CONCLUSIONS

A multifaceted program to improve catheter care was associated with improvement in catheter dressing care but no change in CLABSI rates. Additional study is needed to determine strategies to prevent CLABSI in non–intensive care unit patients.

Infect Control Hosp Epidemiol 2016;37:692–698