bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: SELECTIVE HYDRATION REACTIONS OF ACETYLENIC COMPOUNDS USING MERCURIC SALTS IN AQUEOUS ACID SOLUTION. II. STUDY OF THE EFFECTS OF SALTS ON THE LIFETIME OF THE CATALYST. RESEARCH ON A NEW CATALYTIC SYSTEM
Authors: ARZOUMANIAN HENRI , BERNARD JEAN‐RENE , COSTE CAMILLE , KNOCHE HUBERT , MEALLIER PIERRE
Published: March 2016

Die Hydratisierung von Vinylacetylen im Gemisch mit cis‐ und trans‐2‐Buten und mit Butadien in Gegenwart eines Hg‐Katalysators und die Einflüsse von Na‐p‐toluolsulfonat, Na‐camphosulfonat und Na‐Halogeniden sowie die Hydratisierung mit den neuen Systemen HgO/H2SO4 , HgO/H,SO4 /Mesitylen und HgO/Hz S04 /Benzol werden untersucht.
ChemInform Abstract: NOVEL SYNTHESES IN THE ESTROGEN SERIES
Authors: MALZIEU RENE
Published: March 2016

Die Knoevenagel‐Kondensation der Aldehyde (I) mit Malonsäure ergibt die vinylogen Säuren (II), die mit CHZN, zu (III) verestert werden.
ChemInform Abstract: SYNTHESIS OF ERIOSTOIC ACID AND ERIOSTEMOIC ACID
Authors: TSUKAYAMA MASAO
Published: March 2016

Zur Bestätigung der Strukturen der aus Naturstoffen isolierten Titelsäuren werden ihre Synthesen beschrieben.
ChemInform Abstract: ADDITION OF 2,4‐SUBSTITUTED 5‐AMINOPYRIMIDINES TO ACETYLENEDICARBOXYLIC ACID ESTER
Authors: PRIKAZCHIKOVA L. P. , KURILENKO L. K. , CHERKASOV V. M.
Published: March 2016

Die Aminopyrimidine (I) und (II) lagern sich an den Diester (III) zu linearen Verbindungen (IV) und (V) an, cyclische Verbindungen entstehen nicht.
ChemInform Abstract: REACTIONS OF Π‐CYCLOPENTADIENYL‐(Σ‐FERROCENOYLMETHYL) DICARBONYLIRON WITH ELECTROPHILIC REAGENTS
Authors: NESMEYANOV A. N. , PEREVALOVA E. G. , LEONT'EVA L. I. , GRIGOR'EVA O. V.
Published: March 2016

π‐Cyclopentadienyl‐(a‐ferrocenoyl‐methyl)‐dicarbonyl‐eisen (I) wird durch Quecksilberbromid zu den Verbindungen (II) und (III) gespalten.
ChemInform Abstract: HETEROGENEOUS PHASE‐TRANSFER CATALYSTS‐ ONIUM SALTS, CROWN ETHERS, AND CRYPTANDS IMMOBILIZED ON POLYMER SUPPORTS
Authors: CINOUINI M. , COLONNA S. , MOLINARI H. , MONTANARI F. , TUNDO P.
Published: March 2016

An polymere Träger gebundene Phasentransferkatalysatoren (I)‐(IV) behalten den größten Teil ihrer katalytischen Aktivität und können nach ihrem Einsatz bei nucleophilen Substitutionen durch Filtration zurückgewonnen werden.
ChemInform Abstract: PREPARATION, PHYSICAL PROPERTIES, AND KINETICS OF THE HYDROLYSIS OF SUBSTITUTED α‐CHLOROBENZYL BENZOATES
Authors: EURANTO ERKKI K. , LANKINEN MAILIS , LAPPALAINEN KAIJA
Published: March 2016

Die Titelverbindungen, wie z.B. (I), werden aus den entsprechenden Benzoylchloriden und Benzaldehyden dargestellt.
ChemInform Abstract: (2 + 2)‐CYCLOADDITIONS. 2. (2 + 2)‐CYCLOADDITIONS OF ALKYNES TO ALKENES
Authors: LUKAS JOACHIM H. , BAARDMAN FRANK , KOUWENHOVEN ARJAN P.
Published: March 2016

Unter dem Einfluß von Lewis‐Säuren erfolgt Cycloaddition nicht nur, wie schon bekannt, von Allenen an Alkene, sondern auch von Alkinen an Alkene, wobei die Cyclobutene (III) aus Tetramethyläthylen (I) und den Alkinen (II) entstehen.
ChemInform Abstract: NEW CYCLIC DIARYLBROMONIUM SALTS
Authors: NESMEYANOV A. N. , LISICHKINA I. N. , VANCHIKOV A. N. , TOLSTAYA T. P.
Published: March 2016

o‐Brom‐diphenyl und seine Nitro‐Derivate (I) lassen sich in Essigsäureanhydrid in Gegenwart von Schwefelsäure und Borfluorid‐ ätherat durch eine 10‐fache Menge Wasserstoffperoxid zu Diphenylbromoniumsulfaten (II) oxidieren.
ChemInform Abstract: REACTION OF SULFENE WITH HETEROCYCLIC N,N‐DISUBSTITUTED α‐AMINOMETHYLENE KETONES. IV. SYNTHESIS OF 3,4‐DIHYDRO‐5H‐(1)BENZOTHIOPYRANO(3,4‐E)‐1,2‐OXATHIIN AND 2,3,6,7‐TETRAHYDRO‐5H‐THIOPYRANO(3,4‐E)‐1,2‐OXATHIIN DERIVATIVES
Authors: SCHENONE P. , MOSTI L. , BIGNARDI G.
Published: March 2016

Aus den Hydroxymethylen‐thiapyranonen (I) bzw. (V) entstehen mit Aminen die Aminomethylenverbindungen (II) bzw. (VI), die dann mit Sulfen (III), das aus Methansulfonylchlorid und Triäthylamin hergestellt wird, die Addukte (IV) bzw. (VII) in guten Ausbeuten, auch bei Verwendung sterisch gehinderter Amine, geben.
ChemInform Abstract: REACTIONS OF PALLADIUM(II) CHLORIDE WITH AZIRIDINE RINGS. CATALYTIC REARRANGEMENT OF N‐CARBETHOXY‐8‐AZABICYCLO(5.1.0)OCT‐3‐ENE TO N‐CARBETHOXYNORTROPIDINE
Authors: WIGER GEORGE R. , RETTIG MICHAEL F.
Published: March 2016

Die Aziridine (I) lagern sich unter der Einwirkung des Pd‐Komplexes (II) in Methylenchlorid, Chloroform oder Benzol zu den Nortropidinen (III) um.
ChemInform Abstract: USE OF 18‐CROWN‐6 ETHER FOR THE PHOTOSUBSTITUTION OF SUBSTITUTED AROMATIC DERIVATIVES BY POTASSIUM CYANIDE IN AN ANHYDROUS MEDIUM
Authors: BEUGELMANS R. , LE GOFF M. T. , PUSSET J. , ROUSSI G.
Published: March 2016

[18]Krone‐6 und Kaliumcyanid werden in Methanol gelöst und nach Entfernung des Lösungsmittels mit aromatischen Verbindungen in Acetonitril umgesetzt.
ChemInform Abstract: BIOLOGICALLY ORIENTED ORGANIC SULFUR CHEMISTRY. 14. ANTIINFLAMMATORY PROPERTIES OF SOME ARYL SULFIDES, SULFOXIDES, AND SULFONES
Authors: BRANNIGAN L. H. , HODGE R. B. , FIELD L.
Published: March 2016

Aus 2‐Phenylthio‐benzoesäure (Ia) wird das Säurechlorid (Ib) hergestellt, das über das Diazoketon (Ic) zum homologen Ester (IIa) bzw. der Säure (IIb) führt.
ChemInform Abstract: MALEIC ACID AND FUMARIC ACID ESTERS AS LIGANDS IN METAL CARBONYL COMPLEXES. II. MIXED DICARBONYL AND TRICARBONYL COMPLEXES OF MOLYBDENUM WITH MALEIC ACID AND FUMARIC ACID ESTERS AND BIDENTATE N‐LIGANDS
Authors: SCHAPER H. , BEHRENS H.
Published: March 2016

Die zweikernigen Molybdänkomplexe (I) (Ll‐′Fumar‐ oder Maleinsäureester) bilden mit den Heterocyclen (II) unter CO‐Abspaltung die einkernigen Dicarbonylverbindungen (III).
ChemInform Abstract: BRANCHED SUGARS. PART XII. 1,4‐ADDITION OF CARBANIONS TO PYRANOSIDE ENONES
Authors: PAULSEN H. , KOEBERNICK W. , KOEBERNICK H.
Published: March 2016

Aus dem ungesättigten Zucker (Ia) entsteht mit dem 2‐Lithio‐1,3‐dithian (II) das Addukt (III), dessen Lithiumenolat, das primär gebildet wird, mit Lithiumalanat zu (IV) führt.
ChemInform Abstract: PHASE EQUILIBRIUMS IN METAL‐VANADIUM‐OXYGEN SYSTEMS. INFLUENCE OF TEMPERATURE ON THE PHASE EQUILIBRIUMS IN THE MANGANESE(2+) OXIDE‐VANADIUM(3+) OXIDE‐VANADIUM(4+) OXIDE SYSTEM
Authors: CROS B.
Published: March 2016

Thermodynamische Untersuchungen des Titelsystems zeigen, daß die Phasen vom Typ VnO2n‐1 mit steigender Temperatur stabiler werden, während die Stabilität der Spinel1‐artigen Phasen oberhalb 900°C abnimmt.
ChemInform Abstract: THEORETICAL STUDY OF SN2 REACTIONS. AB INITIO COMPUTATIONS ON HF AND CI LEVEL
Authors: KEIL F. , AHLRICHS R.
Published: March 2016

Die Berechnungen (Hartree‐Fock, configuration interaction) werden für z.B. A‐CHE, + B′ ‐ A" + CH3 ‐B (A, B = H, F, Cl) durchgeführt.
ChemInform Abstract: REACTIONS OF THE K‐REGION OXIDES OF CARCINOGENIC AND RELATED POLYCYCLIC HYDROCARBONS WITH NUCLEOPHILES‐ STEREOCHEMISTRY AND REGIOSELECTIVITY
Authors: BELAND F. A. , HARVEY R. G.
Published: March 2016

Die Reaktion der Epoxide (III), (VII), (X) bzw. (XIII) mit dem Mercaptan (II) (als Modellverbindung) ist stark lösungsmittelabhängig.
ChemInform Abstract: MODIFIED SODIUM BIS(2‐METHOXYETHOXY)ALUMINUM HYDRIDE REAGENTS FOR THE PARTIAL REDUCTION OF LACTONES AND ESTERS
Authors: KANAZAWA R. , TOKOROYAMA T.
Published: March 2016

Lactone (I) werden durch Natrium‐bis‐(2‐methoxäthoxy)‐aluminiumhydrid (II), das zuvor durch Umsetzung mit Äthanol modifiziert wurde, in Toluol bei 0°C selektiv zu Lactolen (III) reduziert.
ChemInform Abstract: PHOTOCHEMICAL FRAGMENTATION OF PHOTOTOXIC 2‐ARYLQUINOLINEMETHANOLS
Authors: EPLING G. A. , AYENGAR N. K.
Published: March 2016

Die nach bekannten Verfahren hergestellten 2‐Arylchinolin‐methanole (I) werden hinsichtlich ihrer Photolyse untersucht.
ChemInform Abstract: FORMATION OF AN AZEPINE BY THE PHOTOCHEMICAL REACTION OF A CYCLOIMMONIUM YLIDE OF THE TYPE N+‐C‐
Authors: LABLACHE‐COMBIER A. , SURPATEANU G.
Published: March 2016

Bei der Photolyse des Isochinolinium‐Ylids (I) erhält man über eine Trimerisicrung durCarbene den Cyclopropan‐hexacarbonester (II), ferner Isochinolin (III), Polymere sowie das Einschiebungsprodukt (IV).
ChemInform Abstract: MAGNETIC PROPERTIES OF LIQUID METALS
Authors: GUENTHERODT H.‐J.
Published: March 2016

Übersicht über Messungen der magnetischen Suszeptibilitäten flüssiger Metalle und Legierungen und Diskussion im Rahmen neuerer Theorien.
ChemInform Abstract: ISOTOPE EFFECTS ON GAS PHASE REACTION PROCESSES. 2. EQUILIBRIUM ISOTOPE EFFECTS ON THE PROTON TRANSFER REACTIONS OF METHYLBENZENES
Authors: WOLF J. F. , DEVLIN J. L. III , DEFREES D. J. , TAFT R. W. , HEHRE W. J.
Published: March 2016

Eine Methylgruppe z.B. in Toluol, Xylol oder Mesitylen stabilisiert eine p‐ständige positive Ladung durch Hyperkonjugation, während der Isotopeneffekt einer O‐Methylgruppe durch andere Faktoren bestimmt wird.
ChemInform Abstract: SOME REARRANGEMENTS INITIATED BY METHYLENETRIPHENYLPHOSPHORANE
Authors: KEUSS H. A. C. M. , LAKEMAN J.
Published: March 2016

Behandlung des Östrendiols (Ia) mit dem Wittig‐Reagenz (II) in DMSO führt zur Umlagerung und dann erst zur beabsichtigten Wittig‐ Reaktion,wobei die epimeren D‐HOmOStCIOiÖC (IIIa) und (IIIb) (65 : 35) entstehen.
ChemInform Abstract: PHOTOCHEMISTRY OF THE CHLOROACETAMIDO FUNCTION‐ SOLVOLYTIC REACTIONS
Authors: KUMAR B. , KALRA S. C. , MEHTA R. M.
Published: March 2016

Die Photolyse des Chloracetamids (I) in Methanol oder Äthanol ergibt die Alkoxyderivate (IIa), während in THF das Amid (IIb) gebildet wird.
ChemInform Abstract: AQUEOUS CHLORINATION OF α‐TERPINEOL
Authors: KOPPERMAN H. L. , HALLCHER R. C. , RIEHL A. , CARLSON R. M. , CAPLE R.
Published: March 2016

Bei der im Bereich pH 2‐10 untersuchten Chlorierung von (I) entstehen als Hauptprodukte im sauren wie im basischen Bereich die HOCl‐Markovnikov‐Addukte (II) und (III).
ChemInform Abstract: THIOARYLIDENEPHTHALIDES AND RELATED COMPOUNDS‐ PART I. SYNTHESIS OF THIO‐ AND D THIONE‐ARYLIDENEPHTHALIDES AND SOME OF THEIR REACTIONS
Authors: HANNOUT I. B. , ISLAM A. M. , EL‐MAGHRABY A. A. , TAHA N. M.
Published: March 2016

Reaktion der BenzaI‐ phthalide (I) mit P2 S5 gibt die Thione (II), die mit HgClg die rotgefärbten Addukte (III) liefern.
ChemInform Abstract: ONE‐FLASK SYNTHESIS OF UNSYMMETRICAL PHOSPHODIESTERS. SELECTIVE AMINE CATALYSIS OF THE PHOSPHORYLATION OF PRIMARY VS. SECONDARY ALCOHOLS
Authors: RAMIREZ F. , MARECEK J. F. , OKAZAKI H.
Published: March 2016

Die zwei unterschiedlichen Alkohole (IV) und (V) werden durch Umsetzung mit dem Phosphorylimidazol (III) ‐ dargestellt aus dem Pyrophosphat (I) und Imidazol (II) ‐ und anschließende Hydrolyse ohne Isolierung von Zwischenprodukten in die unsymm. Phosphorsäurediester (VI) übergeführt.
ChemInform Abstract: 3‐PICOLINE N‐OXIDE COMPLEXES OF RARE‐EARTH BROMIDES
Authors: SIVAPULLAIAH P. V. , SOUNDARARAJAN S.
Published: March 2016

Durch Reaktion der hydratisierten Lanthanidbromide mit dem N‐Oxid werden die Komplexe der Formeln (I) und (II) erhalten.
ChemInform Abstract: CHEMISTRY OF COCCOIDEA. II. CONDENSED POLYCYCLIC PIGMENTS FROM TWO AUSTRALIAN N PSEUDOCOCCIDS (HEMIPTERA)
Authors: BANKS H. J. , CAMERON D. W. , RAVERTY W. D.
Published: March 2016

Die Schildlaus‐Arten Nipaecoccus aurilanatus (Maskell) und Pseudococcus albizziae (Maskell) enthalten als Pigmentsubstanzen die neue Hypericin‐carbonsäure (Ib) und die Anthrachinone (IIa)‐(IIc); darüber hinaus enthalten N. aurilanatus Hypericin (Ia) und das Anthrachinon (III) und P. albizziae die Protohypericine (IVa) und (IVb) sowie Skyrin (V).
ChemInform Abstract: KINETICS OF THE REACTIVE SPUTTER DEPOSITION OF TITANIUM OXIDES
Authors: GERAGHTY K. G. , DONAGHEY L. F.
Published: March 2016

Die reaktive Zerstäubung von Ti in einem Hochfrequenzplasma aus Argon und Sauerstoff wird untersucht.
ChemInform Abstract: STUDIES OF CARBENIUM ION ON UNSATURATED CARBON. II. EXCLUSIVE FORMATION OF BENZOFURANS VIA VINYL CATIONS IN THE SOLVOLYTIC REACTIONS OF 1‐ARYL‐2,2‐BIS(O‐METHOXYPHENYL)VINYL HALIDES
Authors: SONODA T. , KOBAYASHI S. , TANIGUCHI H.
Published: March 2016

Die Solvolyse z.B. der Vinylhalogenide (I) in 80%igem Äthanol bei 120°C in Gegenwart von NaOH liefert das Benzofuran (II); dagegen entsteht bei der entsprechenden Reaktion des Vinylbromids (III) neben dem analogen (IV) als weiteres Produkt das Isomere (V) im Verhältnis 91 : 9. Die Reaktion 1. Ordnung weist einen großen α‐Substituenten‐ und Austrittsgruppeneffekt auf.
ChemInform Abstract: SILICON OXIDATION STUDIES‐ ANALYSIS OF SILICON DIOXIDE FILM GROWTH DATA
Authors: IRENE E. A. , VAN DER MEULEN Y. J.
Published: March 2016

Die Arbeit hat die Aufdeckung der Gründe für die in der Literatur existierenden großen Diskrepanzen bei den kinetischen Konstanten zur Beschreibung der thermischen Oxidation von einkristallinem Si in reinem O2 zum Ziel.
ChemInform Abstract: SYNTHESIS AND CHARACTERIZATION OF A NEW URANIUM(V) COMPOUND‐ OXONIUM HEXAFLUOROURANATE(V)
Authors: MASSON J. P. , DESMOULIN J. P. , CHARPIN P. , BOUGON R.
Published: March 2016

H3O UFg wird als grüner kristalliner Feststoff durch Reaktion äquimolarer Mengen UFS und H2O in HF dargestellt.
ChemInform Abstract: EXOALKYLIDENE SYNTHESIS VIA AZIRIDINIUM YLID. AZYL REACTION
Authors: HATA Y. , WATANABE M.
Published: March 2016

Aus Cyclohexanon (I) wird das Salz (II) hergestellt, das mit Diazomethan zum kondensierten Aziridinium‐Salz (III) führt.
ChemInform Abstract: SYM‐OXEPIN OXIDE
Authors: RASTETTER W. H.
Published: March 2016

Aus Oxepin (I) entsteht mit dem Azoester (II) das Diels‐Alder‐ Addukt (III), das nun die regiospezifische Epoxidation mit p‐Nitro‐perbenzoesäure zum Diepoxid (IV) gestattet.
ChemInform Abstract: THE REACTIONS OF BISAMIDES WITH OXALYL CHLORIDE
Authors: HANAFIN J. , BEN‐ISHAI D.
Published: March 2016

Aus den Alkylidenbisamiden (I) entstehen mit Oxalylchlorid (II) die Imidazolidindione (III).
ChemInform Abstract: POTENTIAL ANTITUMOR AGENTS. 19. MULTIPLY SUBSTITUTED 4′‐(9‐ACRIDINYLAMINO)METHANESULFONANILIDES
Authors: CAIN B. F. , ATWELL G. J.
Published: March 2016

Aus den Salicylaten (I) entstehen mit den Chlorimiden (II) über die Ester (III) die N‐Benzoyl‐diphenylamine (IV), die zu Acridonen (V) cyclisiert werden.
ChemInform Abstract: ADDITION REACTIONS OF HETEROCYCLIC COMPOUNDS. PART LXV. SYNTHESIS, TAUTOMERISM, AND REARRANGEMENT OF SOME 2H‐ AND 4H‐QUINOLIZINE ESTERS
Authors: ACHESON R. M. , HODGSON S. J. , WRIGHT R. G. MCR.
Published: March 2016

Selektive Hydrolyse der Tetracarboxylate (I) gibt die Salze (II), die beim Ansäuem zu den isomeren Triestern (III) und (IV) decarboxyliert werden.
ChemInform Abstract: NUCLEOPHILIC DISPLACEMENT REACTIONS OF 3,6‐DICHLOROPYRIDAZINE 1‐OXIDE WITH SULFUR NUCLEOPHILES
Authors: OCHIAI M. , OKADA T. , MORIMOTO A. , KAWAKITA K.
Published: March 2016

Schwefelhaltige Nucleophjle wie Na2S oder KSH, Benzylmercaptan bzw. Thioharnstoff greifen das Titeloxid (II) in 6‐Stellung an unter Bildung der Derivate (I), (III) bzw. (IV).
ChemInform Abstract: 2‐AMINOPYRROLO(1,2‐A)‐ AND 3‐AMINOPYRROLO(1,2‐C)‐PYRIMIDINES
Authors: DOUGHTY D. G. , GLOVER E. E. , VAUGHAN K. D.
Published: March 2016

Die Umsetzung von 4‐Amino‐6‐methyl‐pyrimidin (II) mit Phenacylbromid und anschließend mit einer Base gibt nicht, wie berichtet wurde, das Imidazopyrimidin (I), sondern über das quaternäre Salz (III) das Pyrrolopyrimidin (IV).
ChemInform Abstract: AZO‐1,3,5‐TRIAZINES
Authors: LOEW P. , WEIS C. D.
Published: March 2016

Cyanurchlorid (I) reagiert‐ mit Hydrazin zum Substitutionsprodukt (IIa), dessen Chloratome zu (IIb) und (IIc) substituiert werden können.
ChemInform Abstract: SYNTHESES AND PROPERTIES OF PHOSPHINO‐ AND PHOSPHINATOPYRAZOLES
Authors: FISCHER S. , HOYANO J. , PETERSON L. K.
Published: March 2016

Die Pyrazolylphosphine und ‐arsin (I) werden durch Reaktion von Chlorphosphinen oder As‐trichlorid mit Pyrazol in Gegenwart von Triäthylamin, mit K‐ pyrazolid in Äther oder Benzol oder mit Trimethylsilylpyrazol ohne Lösungsmittel dargestellt.
ChemInform Abstract: REACTION OF TRANSITION METAL CARBONYLS WITH HETEROCYCLIC SYSTEMS. III. SN2′‐TYPE REACTION OF COMPLEXED Π‐ALLYL SYSTEMS
Authors: BECKER Y. , EISENSTADT A. , SHVO Y.
Published: March 2016

Die Fähigkeit komplexierter π‐A1ly1‐ systeme Austauschreaktionen einzugehen, wurde experimentell untersucht.
Cytologic subclassification of atypia of undetermined significance may predict thyroid nodules more likely to be malignant at surgery
Authors: Shrestha Rupendra T. , Hennessey James V.
Published: March 2016

Background

The atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) category in the Bethesda System of reporting thyroid fine‐needle aspiration (FNA) includes various cytological findings considered to have a low risk of malignancy. It is still unclear if any particular subset of the cytological findings within this category carries a higher risk for malignancy requiring a more aggressive treatment plan.

Methods

We reviewed 221 AUS/FLUS FNAs performed between January of 2006 and May of 2012. Histopathological data from surgery was available in 101 nodules and characteristics of these nodules were analyzed. We reviewed the initial cytology report and subclassified the nodules into one of four groups: architectural atypia (AA, includes abnormal follicular arrangement but no cellular abnormalities), cellular atypia (CA, atypical cellular findings) with or without AA, Hurthle cells Predominant and Others that included otherwise unspecified AUS categories. The surgical pathology confirmed malignancy rate for each group was calculated.

Result

Papillary thyroid carcinoma was the most common malignancy identified (26 of 29 or 90%). We found that in the AA only category, 2/21 (10%) nodules were malignant, whereas when CA with or without AA was present, 23/66 (35%) were malignant, significantly higher than the former group (P values of 0.025).

Conclusion

CA seen on initial AUS/FLUS had a higher malignancy rate compared to AA group. Further research is required to consider subclassification of this category to assign appropriate risk of malignancy for AUS nodules. Diagn. Cytopathol. 2016;44:492–498. © 2016 Wiley Periodicals, Inc.
TiLIA: a software package for image analysis of firefly flash patterns
Authors: Konno Junsuke , Hatta‐Ohashi Yoko , Akiyoshi Ryutaro , Thancharoen Anchana , Silalom Somyot , Sakchoowong Watana , Yiu Vor , Ohba Nobuyoshi , Suzuki Hirobumi
Published: March 2016

As flash signaling patterns of fireflies are species specific, signal‐pattern analysis is important for understanding this system of communication. Here, we present time‐lapse image analysis (TiLIA), a free open‐source software package for signal and flight pattern analyses of fireflies that uses video‐recorded image data. TiLIA enables flight path tracing of individual fireflies and provides frame‐by‐frame coordinates and light intensity data. As an example of TiLIA capabilities, we demonstrate flash pattern analysis of the fireflies Luciola cruciata and L. lateralis during courtship behavior.
Bettungsmodul für Trägerbohlwände in mitteldichtem Sand aus an einem Großversuch validierten FEM‐Berechnungen
Authors: Jung Stefan , Vrettos Christos
Published: March 2016

In der Baugrubenstatik für Trägerbohlwände können die haltenden Kräfte vor dem im Baugrund einbindenden Teil des Trägers mithilfe eines Bettungsmoduls berücksichtigt werden. Ein realitätsnaher Ansatz hierfür muss in der Lage sein, die Abhängigkeit der tatsächlich mobilisierten Erdwiderstandsspannungen von den Verschiebungen und der Wandgeometrie wiederzugeben. Dies war das Ziel der hier vorgestellten Parameterstudie. Die Berechnungen wurden anhand eines 3D‐Modells nach der Finiten‐Elemente‐Methode (FEM) unter Verwendung eines nichtlinearen, elasto‐plastischen Stoffgesetzes für einen typischen mitteldichten Sand, welches anhand bodenmechanischer Laborversuche kalibriert wurde, durchgeführt. Das numerische Modell wurde an Messergebnissen eines instrumentierten Großversuchs validiert. Die maßgebenden Einflussfaktoren auf Größe und Verlauf des Bettungsmoduls wurden an repräsentativen Wandsystemen untersucht. Die Ergebnisse belegen den starken Einfluss der Verschiebung, der Tiefenlage und der Druckflächenbreite. Aus den Parameterstudien wurde ein iterativer, nichtlinearer Berechnungsansatz für den Bettungsmodul hergeleitet.

Subgrade reaction modulus for soldier pile walls in medium‐dense sand from FEM calculations validated on a large‐scale test. In the structural analysis of soldier pile walls, the resisting forces in the soil in front of the embedded pile can be modelled my means of a modulus of subgrade reaction. An adequate approach to this must be able to reproduce the dependency of the actually mobilized earth resistance stresses on the displacements and on the wall geometry. This was the aim of the parametric study presented herein. The calculations were carried out using a 3D model based on the finite element method (FEM) by adopting a nonlinear, elasto‐plastic constitutive law for a typical sand of medium density that has been calibrated from laboratory soil tests. The numerical model has been validated on data obtained from an instrumented large‐scale field test. The factors affecting the magnitude and the distribution of the subgrade reaction modulus were investigated on representative wall systems. The results show the strong influence of the displacement, the depth coordinate, and the width of the beam. The numerical results of the parametric study were subsequently used to derive an iterative, nonlinear relationship for the horizontal subgrade reaction modulus.
Potential Usefulness of BMD and Bone Turnover Monitoring of Zoledronic Acid Therapy Among Women With Osteoporosis: Secondary Analysis of Randomized Controlled Trial Data
Authors: Bell Katy JL , Hayen Andrew , Glasziou Paul , Irwig Les , Eastell Richard , Harrison Stephanie L , Black Dennis M , Bauer Douglas C
Published: March 2016

We aimed to compare the clinical validity and the detectability of response of short-term changes in bone mineral density (BMD; hip and spine) and bone turnover markers (serum PINP and CTX) through secondary analysis of trial data. We analyzed data on 7765 women with osteoporosis randomized to 5-mg once-yearly infusions of zoledronic acid or placebo in the Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly Pivotal Fracture Trial (HORIZON-PFT; trial ran from 2002 to 2006) and the first extension trial (trial ran from 2006 to 2009). We assessed the clinical validity and detectability of response for 1-year measurements of the following monitoring tests: total hip and lumbar spine BMD, serum N-terminal propeptide of type I collagen (sPINP), and serum C-telopeptide of type I collagen (sCTX; 6-month measurement used). Clinical validity was assessed by examining prediction of clinical fracture in Cox models; detectability of response to treatment was assessed by the ratio of signal to noise, estimated from the distributions of change in zoledronic acid and placebo groups. Baseline measurements were available for 7683 women with hip BMD, 558 with spine BMD, 1246 with sPINP, and 517 women with sCTX. Hip BMD and sPINP ranked highly for prediction of clinical fracture, whereas sPINP and sCTX ranked highly for detectability of response to treatment. Serum PINP had the highest overall ranking. In conclusion, serum PINP is potentially useful in monitoring response to zoledronic acid. Further research is needed to evaluate the effects of monitoring PINP on treatment decisions and other clinically relevant outcomes. © 2016 American Society for Bone and Mineral Research.
Structural, Optical and Thermal Study on PEO‐Based Solid Polymer Electrolyte for Optical Device Applications
Authors: Chapi Sharanappa , S. Raghu , V. Mini , K. Archana , Thomas S. , H. Devendrappa
Published: March 2016

The polymer electrolytes based polyethylene oxide‐cobalt chloride (PEO‐CoCl2) films were prepared by solution casting technique and its structural property was examined by XRD study. The XRD data revealed that the amorphous nature of polymer matrix increased with increase of dopant concentration. The absorption spectra was measured in the wave range from 200–800 nm. The direct optical band gap (Eg) found decreased with increasing the concentration of cobalt chloride. The optical activation energy was evaluated using Urbach‐edges method. The thermal properties of these films were investigated with thermogravimetric analysis (TGA). The variation in film morphology is examined by scanning electron microscopy examination (SEM). Studies on the structural and optical properties of polymer electrolyte have attracted much attention in view of their application in optical devices like electro‐chromic display devices, fuel cells, gas sensors and solid state batteries.
High population attributable fractions of myocardial infarction associated with waist–hip ratio
Authors: Egeland Grace M. , Igland Jannicke , Vollset Stein Emil , Sulo Gerhard , Eide Geir Egil , Tell Grethe S.
Published: March 2016

Objective

To estimate population attributable fractions (PAF) of acute myocardial infarction (AMI) associated with anthropometric measures by sex and age.

Methods

The Cohort of Norway study identified 140,790 participants free of cardiovascular disease, 1994‐2003. Participants were followed for AMI through 2009 by record linkages through the Cardiovascular Disease in Norway Project. PAFs were adjusted for age, smoking, systolic blood pressure, diabetes, and the ratio of total cholesterol to high‐density lipoprotein cholesterol.

Results

The PAFs associated with a waist–hip ratio (WHR) in the top two quintiles were 26.1% (95% confidence interval, CI 14.6–36.1) for middle‐aged women (<60 years, mean of 41 years) and 9.3% (95% CI 3.0–15.1) for similarly aged men after adjustment for body mass index (BMI) and conventional risk factors. However, PAFs associated with anthropometric measures in elderly participants (≥ 60 years, mean of 70 years) were non‐significant in multivariable analyses. Also, WHR was a significant predictor of AMI among men and women without an enlarged waist circumference (<102 cm for men and < 88 cm for women) in adjusted analyses.

Conclusions

WHR measurements could improve identification of at‐risk individuals above and beyond that of conventional risk factors, BMI, or an enlarged waist circumference.
Effect of unsaturation in bicarboxylic acid dopants for solid‐state synthesis of polyaniline
Authors: Bhandari Subhendu , Khastgir Dipak
Published: March 2016

Conjugation in the polymeric backbone leads to an electrical conducting nature for conducting polymers, and organic acids can be used as dopants to manipulate the electroactive behaviour. The present investigation deals with the effect of unsaturation in bicarboxylic acid dopant structures on the properties of polyaniline (PAni). PAni was synthesized via solvent‐free solid‐state polymerization. Oxalic acid, fumaric acid and trans,trans‐muconic acid containing 0, 1 and 2 double bonds, respectively, in their molecular structures were used as dopants. Fine particles directionally agglomerate to form nanowires. The use of a conjugated dopant results in highly crystalline PAni. With an increase in the number of double bonds in the dopant structure, the conductivity at room temperature increases, whereas the activation energy, hopping range, optical band gap and supercapacitive performance reduce. The inter‐chain hopping is expected to be favoured by the presence of unsaturation, and even more by conjugation in the dopant structure. © 2016 Society of Chemical Industry
Effect of pipe length on methane explosion in interconnected vessels
Authors: Zhang Kai , Wang Zhirong , Jiang Juncheng , Sun Wei , You Mingwei
Published: March 2016

A series of experiments have been conducted to study the influence of pipe length on methane‐air mixture explosion in linked vessels. Two kinds of setups, that is, a spherical vessel connected to a pipe and two spherical vessels connected by a pipe, are used. The characteristics of explosion pressure and flame propagation speed in linked vessels are obtained. The influence of flame propagation direction and the ignition position on explosion pressure and the flame propagation speed are also analyzed under different pipe lengths. The experimental results show that the maximum explosion pressure and the pressure rising rate in the secondary vessel increase with pipe length. The maximum explosion pressure and pressure rising rate increase most obviously when the small vessel is used as the secondary vessel. Moreover, the pressure oscillation is more violent. However, the primary vessel explosion pressure changes a little when pipe length changed. The flame propagation speed from the primary vessel to the secondary vessel increased with pipe length, but the flame propagation acceleration decreased with pipe length. When the pipe diameter and length is constant, bigger primary vessel causes higher initial flame propagation speed; smaller secondary vessel causes stronger blocking effect during the flame propagation. © 2016 American Institute of Chemical Engineers Process Saf Prog 35: 241–247, 2016
Naturally triggered persistent deep slab avalanches in western Canada Part II: weather trends from model forecasts
Authors: CONLAN MICHAEL , JAMIESON BRUCE
Published: March 2016

For 175 difficult-to-forecast persistent deep slab avalanches, weather data were obtained from Global Environmental Multiscale (GEM) models produced by Environment Canada. The focus was to determine critical parameters and thresholds for avalanche forecasting from GEM and compare them with weather station data analyzed in Part I (Conlan and Jamieson, this issue). The high-resolution GEM-limited-area model (2.5 km resolution) forecasted higher median precipitation amounts than both the lower-resolution GEM15 (15 km resolution) and weather stations within a small dataset. Air temperatures were lower for both weather models compared with the weather station data, likely because of elevation differences. A multivariate classification tree created with GEM15 data correctly classified 29 of 36 avalanches by their primary cause-of-release, using a primary split of modelled solar warming of 5.9°C, 10 cm into the snowpack. For all 175 avalanches, GEM15 forecasted significantly less precipitation than observed at the weather stations, particularly with multi-day cumulative amounts. The majority of GEM15 surface wind speeds were between 0 and 10 km h−1, producing negligible wind loading amounts. The parameter values may be helpful for predicting future persistent deep slab avalanches. However, GEM output is not always representative of field conditions and should be used in conjunction with other sources.
Grass Material as a Modern Process Standard for 14C Analysis of n-Alkanes
Authors: Cisneros-Dozal L M , Xu X , Bryant C , Pearson E J , Dungait J A J
Published: March 2016

One of the difficulties in reporting accurate radiocarbon results from compound-specific radiocarbon analysis (CSRA) is the lack of suitable process standard materials to correct for the amount and 14C content of carbon added during extensive sample processing. We evaluated the use of n-alkanes extracted from modern grass material (1.224±0.006 fraction modern) as process standards for CSRA. The n-alkanes were isolated using preparative capillary gas chromatography (PCGC) from two independent chemical extraction methods applied to the grass. Since this was our first assessment of the 14C content of the grass n-alkanes, we corrected for extraneous carbon derived from PCGC isolation using commercially available single compounds of modern and 14C-free content. Results were consistent across the two extraction methods showing that the C29n-alkane has a fraction modern value that is within 1σ of the bulk value of the grass while C31n-alkane and less abundant n-alkanes have values within 2σ of the bulk value of the grass. C29 and C31n-alkanes were the most abundant n-alkanes in the grass and, as such, the more feasible for collection of sufficient amounts of carbon for accelerator mass spectrometry (AMS) analysis. Our results suggest that choosing a grass n-alkane with an elution time closest to that of the unknowns may be advisable due to possibly greater effect from GC column bleed (14C-free) at later elution times. We conclude that C29 and C31n-alkanes in modern grass of known 14C content can be used as in-house standards to correct for the addition of 14C-free carbon during sample preparation for 14C analysis of n-alkanes.
BAAS Keynote Speech A Passion for Democracy: Proximity to Power and the Sovereign Immunity Test
Authors: NELSON DANA D.
Published: March 2016

In the run-up to the 2004 presidential election, a Bush administration official memorably explained to New York Times reporter Ron Suskind, “when we act, we create our own reality. And while you're studying that reality … we'll act again … We're history's actors … and you … will be left to … study what we do.” This comment was taken both as the administration's assessment of the intellectual left, and as a window into Bush's executive philosophy. Then many believed then that a different President – a liberal or progressive President – would renounce such unilateralism. But these arguments didn't evidence the peculiarity of George W. Bush's Machtpolitik. Rather, they draw on a deep and relatively unnoticed tradition in US political history and government, of the ever more aggressive executive expansion of presidential powers. That expansion has come through the ambitions, machinations, and moxie of individual Presidents – some of them impressively gifted leaders. It has also come through the active and passive consent of citizens, Congress, and the Supreme Court. The President has come to symbolize both our democratic process and our national power: citizens see him simultaneously as democracy's heart and its avenging sword. That trust, trained into US citizens from our earliest days in school, reinforced by popular culture and by the media, makes citizens want to give the President more power, regardless of the Constitutional checks and balances we also learn to treasure as schoolchildren. Over time, this accumulating consent to ever-increasing presidential power means that Presidents are free to act – even in ways that upset the Constitution's balance of power – and that citizens by and large approve, and those who don't are left studying what they did.
The complete mitochondrial genome of Orthocoelium streptocoelium (Digenea: Paramphistomidae) for comparison with other digeneans
Authors: Zhao Y.Y. , Yang X. , Chen H.M. , Wang L.X. , Feng H.L. , Zhao P.F. , Tan L. , Lei W.Q. , Ao Y. , Hu M. , Fang R.
Published: March 2016

Orthocoelium streptocoelium is a common paramphistome species parasitizing the rumen and/or reticulum of small ruminants, leading to significant losses. This study first determined the complete mitochondrial (mt) genome of O. streptocoelium. The complete mt genome of O. streptocoelium was amplified, sequenced, assembled, analysed and then compared with those of other digeneans. The entire mt genome of O. streptocoelium is 13,800 bp in length, which is smaller than those of other digeneans except for Opisthorchis viverrini. This mt genome contains 12 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and two non-coding regions. The arrangement of the O. streptocoelium mt genome is the same as those of other digeneans except for Schistosoma haematobium and Schistosoma spindale. Phylogenetic analyses based on concatenated amino acid sequences of the 12 protein-coding genes representing 16 digeneans were conducted to assess the relationship of O. streptocoelium with other digeneans. The result indicated that O. streptocoelium is closely related to Paramphistomum cervi and Fischoederius elongates, which is in accordance with their relationships by taxonomy. This complete mt genome of O. streptocoelium enriched the mitochondrial genome data of paramphistomes and provided important molecular markers for diagnostics and studies of population variation, epidemiology, ecology and evolution of O. streptocoelium and other digeneans.
Using linear constraints for logic program termination analysis
Authors: CALAUTTI MARCO , GRECO SERGIO , MOLINARO CRISTIAN , TRUBITSYNA IRINA
Published: March 2016

It is widely acknowledged that function symbols are an important feature in answer set programming, as they make modelling easier, increase the expressive power, and allow us to deal with infinite domains. The main issue with their introduction is that the evaluation of a program might not terminate and checking whether it terminates or not is undecidable. To cope with this problem, several classes of logic programs have been proposed where the use of function symbols is restricted but the program evaluation termination is guaranteed. Despite the significant body of work in this area, current approaches do not include many simple practical programs whose evaluation terminates. In this paper, we present the novel classes ofrule-boundedandcycle-bounded programs, which overcome different limitations of current approaches by performing a more global analysis of how terms are propagated from the body to the head of rules. Results on the correctness, the complexity, and the expressivity of the proposed approach are provided.
Pulsars
Authors: Hewish A.
Published: March 2016

It seems hard to realise, today, that pulsars were totally unknown at the time of the last General Assembly. The discovery of pulsars dates from November 28th, 1967, when the first pulses were recorded from the source now known as CP 1919. Since then we have witnessed an astonishing phase of activity, amongst observers and theoreticians alike, which may be unique in the history of astronomy. Now, with at least 50 pulsars in the catalogues, we are in possession of a wealth of information about these remarkable sources. My aim tonight is to outline the observational evidence which leads us to the physical nature of pulsars. I shall happily leave to Professor Ginzburg the far more difficult task of weaving these strands into a logical pattern
and devising a model to account for what is observed.
Pulsars (Theoretical Considerations)
Authors: Ginzburg V. L.
Published: March 2016

Theorists, both physicists and astronomers, are usually greatly pleased with their choice, because to study theoretical questions is, in a sense, easier and more effective than to observe and to measure. Experimentalists and observers, on the other hand, often grumble at their fortune for their work is very labour-consuming and its success depends largely on quite non-scientific problems, such as getting money, equipment and so on. I should like to mention this because the study of pulsars can serve as an example (not, of course, the only one) when the theorists have every reason for envying the observers. At any rate as far as I am concerned, this is so. In the previous report made by A. Hewish the facts were presented and we have every reason for congratulating the observers on their success. In less than three years great work has been done. As for the theory of pulsars we have, for the time being, a shortage of exactly established facts and I would like to discuss mainly general considerations and working hypotheses. Fortunately, for the theorists the situation is not always like that. There are cases when theory goes far ahead and anticipates observations. In the case of pulsars some lag in the theory is caused by two circumstances. Firstly we deal here with exceptionally complicated tasks, for example, with the equation of state of a substance with a density ℓ ≿ 1011 g cm−3 and the electrodynamics of the magnetosphere of a rapidly rotating star with non-coinciding axes of rotation and of magnetic symmetry (say, with the direction of magnetic dipole). Secondly the observational data, in spite of their variety, give only indirect information about pulsars because their structure cannot be seen directly as, for example, in the case of the surface of the Sun or a number of nebulae.
Observational Evidence for Galactic Spiral Structure
Authors: Bok Bart J.
Published: March 2016

Does our Galaxy possess spiral structure and, if so, can this structure be traced observationally with some degree of confidence? This is the major question to which I shall address myself tonight. Following my talk, Professor Lin will speak about the theoretical aspects of spiral structure. I shall be very brief in my references to spiral structure in galaxies outside our own and leave it largely to Professor Lin to speak about observations on other spiral galaxies and their relevance for possible theoretical interpretations.

A year ago, my good and distinguished friend Professor B. A. Vorontsov-Velyaminov chided me in his address at the Basel Symposium for having been too eager to accept the fact that observation suggests that our Galaxy really possesses spiral structure. I hope to show in my Discourse that for our Galaxy we have indeed evidence for the presence of an underlying structure of spiral features.
Theory of Spiral Structure
Authors: Lin C. C.
Published: March 2016

It is an honor for me to continue the discussion of galactic spirals following Professor Bok, who has contributed to the subject for many years. My experience has been relatively short. My first encounter with the study of galactic spirals occurred in 1961, when I was invited by Professor Bengt Strömgren to attend a conference on interstellar matter at Princeton, N.J. There I first learned about the winding dilemma from Professor Jan Oort. After the conference, Professor Lodewijk Woltjer, who edited the Proceedings, visited me for about a month. Thus, I began slowly to learn about spiral galaxies and to work on the subject. It turned out to be an extremely rewarding experience, for the observational data were already ripe for theoretical analysis, and the hydromagnetic theory of spiral arms was clearly encountering great difficulties. Since I was not educated as an astronomer, I owe my gratitude to Professors Strömgren, Woltjer, and Kevin Prendergast, on whom I depended for correct astronomical facts as I started my work. Without their help, I would not be standing here today. Later on, I was to receive help from many other distinguished astronomers, including Professor Bok from whom you just heard. I am greatly impressed with the community of astronomers as a dedicated group of scientists.
Opening Remarks at Joint Discussion on the Helium in the Universe
Authors: Osterbrock D. E.
Published: March 2016

I wish to thank the Organizing Committee members who planned and organized this Joint Discussion - Professor Fowler, who will preside this afternoon, Dr Hearn, Dr Reeves, Professor Tayler, Professor Underhill, Professor Wallerstein, and Professor Mathis, who has consented to edit the published proceedings.

We feel we have assembled a team of the world’s greatest experts on the helium problem, and we know that there are many other even greater experts in the audience. The general idea of the program is that the first session will be devoted to deductions about what the abundance (or abundances) of helium is (or are) in various objects, and the second session to what these abundances imply about stellar, galactic, or universal evolution. We very much want to encourage discussion and the presentation of new results following each review paper.

It is particularly appropriate to discuss helium at this IAU General Assembly in England, as this element was discovered in 1868 by Sir Norman Lockyer, who measured λ5876 in the spectrum of the chromosphere, and realized that none of the then known elements could produce it. Helium is thus a real British astronomical element. Furthermore, helium was first identified on the Earth by Sir William Ramsay, who observed the same line in the gas obtained from uranium, and thus showed it was a terrestrial element too.
The Abundance of Helium in Stellar Interiors
Authors: Faulkner John
Published: March 2016

From the titles of the other contributions to this morning’s session, one deduces that the hard facts of theory are to be sandwiched between the loose speculations of direct observation. I shall therefore feel free to discuss theoretical implications from stellar structure unencumbered by what are, after all, but peripheral considerations.

I should, however, begin with an apology. It is impossible to do even minimal justice to the vast number of investigations which have contributed to our present understanding (or lack of it). The choice of topics has been dictated in part by history, in part by current relevance, but mainly by personal whim. While much of the discussion centres, for obvious reasons, on Population II work, one or two problems associated with Population I will also be considered. Reference may be made to the exhaustive review article of Iben (1967) and also to the Warner Prize Lecture by Demarque (1968) for background and a more complete discussion of some of the points which will be touched upon here.

I shall assume today that the ‘normal’ helium content of stars is of the order of 25±5% by mass. This leaves me free to pay particular attention to systems which do not appear to adhere to this generalization, systems for which abnormally high or low helium contents have been claimed. The main point of my talk is that there is no really convincing, concrete evidence from stellar interiors alone for helium contents far removed from normal. During the course of the past decade, this has come to be largely accepted. It is in a way sad to see the radicalism of one’s youth become the orthodoxy of middle age.
Abundances of Helium in Gaseous Nebulae
Authors: Seaton M. J.
Published: March 2016

During the past two or three years much work has been done on the determination of helium abundances in gaseous nebulae, using observations at both optical wavelengths and radio wavelengths. I imagine that the organisers of this Discussion must have asked whether the subject should be reviewed by an optical observer or a radio observer, and have finally resolved their dilemma by choosing a speaker who has not made observations at any wavelength whatsoever.
Helium Production in the Different Cosmological Models
Authors: Doroshkevich A. G. , Novikov I. D. , Sunyaev R. A. , Zeldovich Ya. B.
Published: March 2016

The aim of the present report is to emphasize the role of the helium problem as the key one for different aspects of cosmological speculations. This is not surprising, because the processes which produce the helium and other elements in primordial matter take place during the first stages of the cosmological expansion of the Universe.

The theory gives three critical values of the He4 abundance in pre-stellar matter, depending on assumptions about the behaviour of the Universe near the singularity. The three critical values are:

(1) practically no He4 at all;

(2) about 25% of He4 by mass;

(3) practically entirely He4.

Although intermediate values of He4 are in principle possible, the cosmological models permitting such values are highly improbable. It is obvious that the helium abundance is less than 100%, and that even rough estimates of whether the stellar matter consists almost entirely of hydrogen, or if it has a significant part of He4, are of tremendous importance. The much-more-difficult determination of traces of primeval He3, D, Li6, would be of great help in making definite cosmological conclusions.
Helium in the Universe: Final Summary
Authors: Burbidge G.
Published: March 2016

It is my task to summarize for you what we have learned today about the helium problem. Before attempting this, let me first very briefly outline the problem as it appears to us in 1970. It amounts to the questions: What is the fractional abundance of helium in different regions in the universe, is it the same in all places, and how did it originate?

The simple answers to these questions which appealed to many and seemed to have a reasonable basis in fact a few years ago were:

The He/H ratio is of ~ 25-30% by mass; the ratio is the same everywhere, and the helium was most probably synthesized in the early stages of a primordial fireball in which the universe began. However, for some time it has been clear that the situation is more complicated than this, as I pointed out in an article published last year in Comm. Astrophys. Space Sci.