bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: CONFORMATIONAL DISSYMMETRY. CONFORMATIONAL ISOMERS OF BIS((R,S)‐2,4‐PENTANEDIAMINE) COMPLEXES
Authors: BOUCHER H. , BOSNICH B.
Published: March 2016

Die fünf möglichen Konformationsisomeren des Ions (I) werden mittels einer Reihe kinetischer und thermodynamischer Methoden dargestellt.
ChemInform Abstract: METHYLATION OF ZINC(II), CADMIUM(II), AND LEAD(II) BY A TRANS‐DIMETHYLCOBALT COMPLEX
Authors: WITMAN M. W. , WEBER J. H.
Published: March 2016

Die Dealkylierungsreaktionen des Komplexes (I), einen durch Kondensation von Butandion(2,3)‐monoxim und 1,3‐Diaminopropan gebildeten vierzähnigen Dioxim‐Diimin‐Liganden enthaltend, durch Zn‐, Cd‐ und Pb‐Ionen in iso‐Propanol ′ werden diskutiert.
ChemInform Abstract: BIS(ETHYLENEDIAMINE)(L‐2,3‐DIAMINOPROPIONIC ACID)PLATINUM(IV) CHLORIDE. PREPARATION, RESOLUTION, AND DETERMINATION OF ABSOLUTE CONFIGURATION
Authors: LIU C. F. , YOO M. K.
Published: March 2016

Der Komplex (I) wird durch Reaktion von K‐tetrachloroplatinat(II) mit L‐2,3‐Diaminopropionsäure in verdünnter Salzsäure dargestellt und mit Chlor zu (II) oxidiert.
ChemInform Abstract: NOVEL TRIARYLOXO‐ AND TRIAROYLOXOSTANNYL TRANSITION METAL COMPLEXES
Authors: COULSON D. R. , SEIWELL L. P.
Published: March 2016

Durch Zugabe von THF zu einer Mischung von Phenol bzw. Benz esäure, Sn(O‐Me)2 und Naphenolat bzw. Na‐benzoat wurden die Sn‐Verbindungen I) als Na‐Salze mit THF als Solvatmolekül erhalten.
ChemInform Abstract: A NEW CLASS OF HYDRIDE‐BRIDGED PLATINUM COMPLEX WITH APPLICATION AS HYDROSILYLATION CATALYSTS, MOLECULAR AND X‐RAY CRYSTAL STRUCTURE OF TRANS‐DI‐μ‐HYDRIDO‐BIS(TRICYCLOHEXYLPHOSPHINE)BIS(TRIETHYLSILYL)DIPLATINUM(P# T‐PT)
Authors: GREENN M. , HOWARD J. A. K. , PROUD J. , SPENCER J. L. , STONE F. G. A. , TSIPIS C. A.
Published: March 2016

Durch Hydrierung des Platin‐Komplexes (I) oder Umsetzung mit den Hydriden (III) entstehen die Hydrid‐verbrückten Komplexe (II) bzw. (IV).
ChemInform Abstract: DYES FOR ENERGY CONVERSIONS
Authors: ROCHLITZ J.
Published: March 2016

Das Übersichtsreferat befaßt sich mit der Anwendung von Farbstoffen in der Lasertechnik, mit der Sensibilisierung von Reaktionen an Halbleitern, mit der Verwendung von Farbstoffen in photoleitenden Schichten aus organischen Verbindungen, in Photovoltazellen, photogalvanischen und galvanischen Elementen.
ChemInform Abstract: INDIGOID PYRROLE AND PYRIDINE DYES
Authors: BAUER H. , PFEIFFER G.
Published: March 2016

Bei einem theoretischen und experimentellen Vergleich des chromophoren Systems von Pyrrolinindigo und verwandten Verbindungen mit den entsprechenden benzoanellierten Verbindungen werden keine wesentlichen Unterschiede festgestellt, jedoch ist die Polarität der erstgenannten Gruppe größer.
ChemInform Abstract: OXIDATION OF 2‐ AND 3‐OXOSTEROIDS. II. OXIDATION OF 3‐OXOSTEROIDS WITH OXYGEN N IN BASIC SOLUTION
Authors: NAKAJIMA S. , KONAKA R. , TAKEDA K.
Published: March 2016

Zahlreiche 3‐Oxo‐Steroide werden in Gegenwart von Kaliumtert.‐butylat mit Luftsauerstoff zu 2,3‐ und 3,4‐Dionen oxidiert, die teilweise acetyliert werden.
ChemInform Abstract: ACTIVATION OF CARBOXYLIC ACIDS AS DIPHENYLPHOSPHINIC MIXED ANHYDRIDES. APPLICATION TO PEPTIDE CHEMISTRY
Authors: JACKSON A. G. , KENNER G. W. , MOORE G. A. , RAMAGE R. , THORPE W. D.
Published: March 2016

Pivalylchlorid (II) reagiert mit dem Diphenylphosphinat (I) zum gemischten Anhydrid (III), das mit Phenäthylamin (IV) zum Amid (V) reagiert.
ChemInform Abstract: REACTION OF ACETYLGLYCALS AND ACETYLPSEUDOGLYCALS WITH SODIUM SALT CATALYZED BY BORON TRIFLUORIDE
Authors: HEYNS K. , JA IN PARK JA IN PARK
Published: March 2016

Die Glycale (I), (VI), (X) bzw. (XIII) reagieren mit dem Na‐Salz (II) unter BF3‐ätherat‐Katalyse zu den kettenverzweigten Desoxyhexenopyranosen (IIIa) und (IIIb) [daneben das Pseudoglucal (IV); die gleichen Produkte entstehen auch aus der Verbindung (V) (Ausbeuteangaben in mg)] bzw. (VIIa) und (VIIb) [daneben das Pseudorhamnal (VIII); Bildung der gleichen Produkte auch aus der Verbindung (IX) (Ausbeuteangaben in mg)] bzw. (XI) [daneben das Pseudogalactal (XII)] bzw. (XIV) [daneben das Pseudoxylal (XV)].
ChemInform Abstract: INVESTIGATION ON THE CHEMISTRY OF BERBANS, IV. SYNTHESIS OF HALOGEN CONTAINING DEPYRROLOYOHIMBONE DERIVATIVES WITH PG‐LIKE AND PG‐ANTAGONISTIC EFFECT
Authors: SZABO L. , TOTH I. , TOEKE L. , KOLONITS P. , SZANTAY CS.
Published: March 2016

Die Halogenierung von Despyrroloyohimbon‐Derivaten verschiedener Konstitution wie z.B. (I), (IV), (VII) und (X) wird untersucht, um brauchbare Intermediärprodukte zur Synthese von Despyrroloreserpinen zu gewinnen.
ChemInform Abstract: SYNTHESIS OF C‐NUCLEOSIDES. 13. S‐TRIAZOLO(4,3‐A)‐ AND ‐(1,5‐A)PYRIDINE DERIVATIVES
Authors: HUYNH‐DINH T. , IGOLEN J. , MARQUET J. P. , BISAGNI E. , LHOSTE J. M.
Published: March 2016

2‐Hydrazino‐pyridin (I) reagiert mit den Thioacetirnidaten (II) zu den Cyclisierungsprodukten (III).
ChemInform Abstract: NUCLEOSIDES. 101. CONFORMATIONALLY RESTRICTED ANALOGS OF PYRIMIDINE NUCLEOSIDES. 1. SYNTHESIS OF 6,5′(S)‐ AND 6,5′(R)‐CYCLOURIDINE
Authors: OTTER B. A. , FALCO E. A. , FOX J. J.
Published: March 2016

Aus dem 5‐Acetoxy‐2′,3′‐isopropyliden‐uridin (Ia) entsteht der Aldehyd (Ib), der über das Imidazolidin‐Derivat (Ic) zum anhydro‐Nucleosid (IIa) führt.
ChemInform Abstract: TRANSFORMATIONS OF PENICILLINS‐ NEW METHODS OF FORMATION AND REACTIONS OF 6,6‐DISUBSTITUTED PENAMS AND 7,7‐DISUBSTITUTED CEPHEMS
Authors: BREMNER D. H. , CAMPBELL M. M. , JOHNSON G.
Published: March 2016

Die Reaktion der Penicillansäurederivate (II) mit dem Carbamat (Ia) in Acetonitril liefert die Äthoxyformamidoderivate (III), von denen (IIIa), (IIIc) bzw. (IIId) zu den entsprechenden Sulfonen (IV) oxidiert werden.
ChemInform Abstract: NEW FLASH EVAPORATION METHOD IMPROVES FILM PREPARATION
Authors: PLATAKIS N. S. , GATOS H. C.
Published: March 2016

Mit einer neuentwikkelten Flashverdampfungsmethode, die die Hauptnachteile der herkömmlichen Methoden ausschaltet, werden bezüglich Struktur und chemischer Homogenität signifikant verbesserte Filme erhalten.
Pharmacokinetics of the Novel Nonsteroidal Mineralocorticoid Receptor Antagonist Finerenone (BAY 94–8862) in Individuals With Renal Impairment
Authors: Heinig Roland , Kimmeskamp‐Kirschbaum Nina , Halabi Atef , Lentini Silvia
Published: March 2016

Finerenone (BAY 94–8862) is a nonsteroidal mineralocorticoid receptor antagonist in development for the treatment of diabetic kidney disease. This observational trial compared the pharmacokinetics of a single oral dose of finerenone 10 mg (immediate‐release tablet) in adults with mild (creatinine clearance [CLCR] 50–80 mL/min; n = 8), moderate (CLCR 30 to < 50 mL/min; n = 8), or severe (CLCR < 30 mL/min; n  =  9) renal impairment with those in adults with normal renal function (CLCR > 80 mL/min; n  = 8) over 96 hours postdose. Exposure to finerenone was not affected by mild renal impairment. In participants with moderate or severe renal impairment, exposure to finerenone was increased compared with those with normal renal function (increase in area under the curve for unbound finerenone, 57.1% [outlier excluded] and 46.5%, respectively), with moderate to high interindividual variability. Renal impairment had no consistent effect on the maximum plasma concentration, Cmax (differences in Cmax for unbound finerenone of +12% and –7% with moderate [outlier excluded] and severe impairment vs normal renal function, respectively). Renal elimination of finerenone is minimal. However, changes in exposure may occur because of the effects of renal impairment on nonrenal routes of elimination.
Morphology of Imidazolium‐Based Ionic Liquids as Deposited by Vapor Deposition: Micro‐/Nanodroplets and Thin Films
Authors: Costa José C. S. , Mendes Adélio , Santos Luís M. N. B. F.
Published: March 2016

The morphology of micro‐ and nanodroplets and thin films of ionic liquids (ILs) prepared through physical vapor deposition is presented. The morphology of droplets deposited on indium‐tin‐oxide‐coated glass is presented for the extended 1‐alkyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide ([CnC1im][Ntf2]; n=1–8) series, and the results show the nanostructuration of ILs. The use of in‐vacuum energetic particles enhances/increases the nanodroplets mobility/coalescence mechanisms and can be a pathway to the fabrication of thin IL films.
Room‐Temperature Synthesis of Mesoporous Sn/SnO2 Composite as Anode for Sodium‐Ion Batteries
Authors: Tang Duihai , Huang Qingquan , Yi Ran , Dai Fang , Gordin Mikhail L. , Hu Shi , Chen Shuru , Yu Zhaoxin , Sohn Hiesang , Song Jiangxuan , Wang Donghai
Published: March 2016

A mesoporous Sn/SnO2 composite has been synthesized by a self‐templating pore formation process at room temperature without any external templates. When evaluated as an anode for sodium‐ion batteries, the composite material exhibited stable performance and high Coulombic efficiency, in addition to excellent rate performance.
Securing Important Strigolactone Key Structures: Orobanchol and 5‐Deoxystrigol
Authors: Zwanenburg Binne , Regeling Henk , van Tilburg‐Joukema Colinda W. , van Oss Bram , Molenveld Peter , de Gelder René , Tinnemans Paul
Published: March 2016

Strigolactones (SLs) constitute an important new class of plant hormones. Their isolation from natural resources, such as root exudates, is laborious and difficult. Therefore, synthetic SLs are needed to discover their (biological) properties. Such syntheses involve many steps. When repeating a published procedure for the synthesis of orobanchol, we noticed that the structure of the synthesized material was ambiguous. This structure was secured by means of X‐ray analysis. An essential step in the synthesis, namely an allylic oxidation of the ABC scaffold, was significantly improved by using Pd/C and tert‐butyl hydroperoxide (Corey's method). The second issue deals with the structure of the four stereoisomers of 5‐deoxystrigol. The stereochemistry of these compounds was based on the use of Welzel's empirical rules for CD spectra. By means of X‐ray analysis the stereochemistry of one of the stereoisomers was established unambiguously, thereby securing the configuration of all four isomers.
Polyphenols from halophytes and modified atmosphere packaging improve sensorial and biochemical markers of quality of common dolphinfish (Coryphaena hippurus) fillets
Authors: Messina Concetta Maria , Bono Gioacchino , Arena Rosaria , Randazzo Mariano , Manuguerra Simona , Santulli Andrea
Published: March 2016

Quality and shelf‐life of whole and filleted Coryphaena hippurus, stored with modified atmosphere packaging (MAP) and natural antioxidants from halophytes (HAL), were investigated. Fillets were divided into control, simply sealed in trays; MAP, preserved by modified atmosphere (45% CO2, 50% N2, 5% O2); and MAP‐HAL, pretreated with antioxidants and preserved by MAP. Whole and filleted fish were stored at −1 ± 0.5°C for 18 days. The quality of the samples was analyzed at the time of packaging and after 3, 6, 9, 12, 15, and 18 days. The MAP and MAP‐HAL groups maintained the best sensorial profile, pH, and drip loss with respect to the untreated fillets. Higher levels of total volatile basic nitrogen (TVB‐N) and oxidized proteins were observed in untreated samples with respect to the MAP and MAP‐HAL groups. The principle component analysis revealed a different quality profile for untreated and MAP‐treated fish.
Sodium signaling and astrocyte energy metabolism
Authors: Chatton Jean‐Yves , Magistretti Pierre J. , Barros L. Felipe
Published: March 2016

The Na+ gradient across the plasma membrane is constantly exploited by astrocytes as a secondary energy source to regulate the intracellular and extracellular milieu, and discard waste products. One of the most prominent roles of astrocytes in the brain is the Na+‐dependent clearance of glutamate released by neurons during synaptic transmission. The intracellular Na+ load collectively generated by these processes converges at the Na,K‐ATPase pump, responsible for Na+ extrusion from the cell, which is achieved at the expense of cellular ATP. These processes represent pivotal mechanisms enabling astrocytes to increase the local availability of metabolic substrates in response to neuronal activity. This review presents basic principles linking the intracellular handling of Na+ following activity‐related transmembrane fluxes in astrocytes and the energy metabolic pathways involved. We propose a role of Na+ as an energy currency and as a mediator of metabolic signals in the context of neuron–glia interactions. We further discuss the possible impact of the astrocytic syncytium for the distribution and coordination of the metabolic response, and the compartmentation of these processes in cellular microdomains and subcellular organelles. Finally, we illustrate future avenues of investigation into signaling mechanisms aimed at bridging the gap between Na+ and the metabolic machinery. GLIA 2016;64:1667–1676
Healthcare Coinsurance Elasticity Coefficient Estimation Using Monthly Cross‐sectional, Time‐series Claims Data
Authors: Scoggins John F. , Weinberg Daniel A.
Published: March 2016

Published estimates of the healthcare coinsurance elasticity coefficient have typically relied on annual observations of individual healthcare expenditures even though health plan membership and expenditures are traditionally reported in monthly units and several studies have stressed the need for demand models to recognize the episodic nature of healthcare. Summing individual healthcare expenditures into annual observations complicates two common challenges of statistical inference, heteroscedasticity, and regressor endogeneity. This paper estimates the elasticity coefficient using a monthly panel data model that addresses the heteroscedasticity and endogeneity problems with relative ease. Healthcare claims data from employees of King County, Washington, during 2005 to 2011 were used to estimate the mean point elasticity coefficient: −0.314 (0.015 standard error) to −0.145 (0.015 standard error) depending on model specification. These estimates bracket the −0.2 point estimate (range: −0.22 to −0.17) derived from the famous Rand Health Insurance Experiment. Copyright © 2016 John Wiley & Sons, Ltd.
Demographics and Business Cycle Volatility: A Spurious Relationship?
Authors: Everaert Gerdie , Vierke Hauke
Published: March 2016

This paper replicates the estimation results of three studies on the impact of the age composition of the labor force on business cycle volatility and investigates whether they signal a meaningful long‐run relationship. We show that both the volatile‐age labor force share variable and the business cycle volatility measure exhibit non‐stationary behavior but find no robust evidence of cointegration. Hence the estimation results reported in the literature may be spurious. This conclusion is further supported by the finding that the strong relationship (i) disappears when cross‐sectional dependence is accounted for using the CCEP estimator and (ii) is highly sensitive to small changes in the composition of the sample, to data revisions, and to the exact definition of the volatile‐age labor share. Copyright © 2016 John Wiley & Sons, Ltd.
Cellular Hypoxia Promotes Heterotopic Ossification by Amplifying BMP Signaling
Authors: Wang Haitao , Lindborg Carter , Lounev Vitali , Kim Jung-Hoon , McCarrick-Walmsley Ruth , Xu Meiqi , Mangiavini Laura , Groppe Jay C , Shore Eileen M , Schipani Ernestina , Kaplan Frederick S , Pignolo Robert J
Published: March 2016

Hypoxia and inflammation are implicated in the episodic induction of heterotopic endochondral ossification (HEO); however, the molecular mechanisms are unknown. HIF-1α integrates the cellular response to both hypoxia and inflammation and is a prime candidate for regulating HEO. We investigated the role of hypoxia and HIF-1α in fibrodysplasia ossificans progressiva (FOP), the most catastrophic form of HEO in humans. We found that HIF-1α increases the intensity and duration of canonical bone morphogenetic protein (BMP) signaling through Rabaptin 5 (RABEP1)-mediated retention of Activin A receptor, type I (ACVR1), a BMP receptor, in the endosomal compartment of hypoxic connective tissue progenitor cells from patients with FOP. We further show that early inflammatory FOP lesions in humans and in a mouse model are markedly hypoxic, and inhibition of HIF-1α by genetic or pharmacologic means restores canonical BMP signaling to normoxic levels in human FOP cells and profoundly reduces HEO in a constitutively active Acvr1Q207D/+ mouse model of FOP. Thus, an inflammation and cellular oxygen-sensing mechanism that modulates intracellular retention of a mutant BMP receptor determines, in part, its pathologic activity in FOP. Our study provides critical insight into a previously unrecognized role of HIF-1α in the hypoxic amplification of BMP signaling and in the episodic induction of HEO in FOP and further identifies HIF-1α as a therapeutic target for FOP and perhaps nongenetic forms of HEO. © 2016 American Society for Bone and Mineral Research.
Methane oxidation at the water‐ice interface of an ice‐covered lake
Authors: Ricão Canelhas Monica , Denfeld Blaize A. , Weyhenmeyer Gesa A. , Bastviken David , Bertilsson Stefan
Published: March 2016

Lakes are important components of the global methane (CH4) cycle. In seasonally ice‐covered lakes, CH4 transported by ebullition (bubbling) from anoxic sediments gets trapped at the water‐ice interface. If not oxidized by methane‐oxidizing bacteria (MOB), this can potentially lead to high episodic CH4 emissions at ice‐melt. To understand the fate of CH4 trapped below ice, we measured depth‐distributions of CH4 concentrations in the water column near bubbles trapped below ice in Lake Erken. We also performed a 21 d incubation experiment at low temperature (2.3 ± 0.2°C) to investigate the potential for CH4 oxidation. During most sampling occasions, we found steep CH4 concentration gradients just below the ice with a 13‐fold decrease from the surface to a depth of 20 cm. In vitro incubations revealed that CH4 oxidation can occur at low temperatures typical for the water‐ice interface. CH4 oxidation was observed as a significant decrease in CH4 concentration, a significant increase in stable isotope 13C signature, and an increase in MOB during the incubation. Thus, CH4 accumulating in the top 20 cm of the water column, fed by diffusion from CH4 in trapped bubbles, may fuel significant CH4 oxidation. Since northern latitude lakes can be ice‐covered for many months of the year and significant amounts of CH4 accumulate below the ice, the extent of CH4 oxidation under these low temperature‐conditions is important for understanding the potential CH4 emissions to the atmosphere during ice‐melt.
Development of a normothermic extracorporeal liver perfusion system toward improving viability and function of human extended criteria donor livers
Authors: Banan Babak , Watson Rao , Xu Min , Lin Yiing , Chapman William
Published: March 2016

Donor organ shortages have led to an increased interest in finding new approaches to recover organs from extended criteria donors (ECD). Normothermic extracorporeal liver perfusion (NELP) has been proposed as a superior preservation method to reduce ischemia/reperfusion injury (IRI), precondition suboptimal grafts, and treat ECD livers so that they can be successfully used for transplantation. The aim of this study was to investigate the beneficial effects of a modified NELP circuit on discarded human livers. Seven human livers that were rejected for transplantation were placed on a modified NELP circuit for 8 hours. Perfusate samples and needle core biopsies were obtained at hourly intervals. A defatting solution that contained exendin‐4 (50 nM) and L‐carnitine (10 mM) was added to the perfusate for 2 steatotic livers. NELP provided normal temperature, electrolytes, and pH and glucose levels in the perfusate along with physiological vascular flows and pressures. Functional, biochemical, and microscopic evaluation revealed no additional injuries to the grafts during NELP with an improved oxygen extraction ratio (>0.5) and stabilized markers of hepatic injury. All livers synthesized adequate amounts of bile and coagulation factors. We also demonstrated a mild reduction (10%) of macroglobular steatosis with the use of the defatting solution. Histology demonstrated normal parenchymal architecture and a minimal to complete lack of IRI at the end of NELP. In conclusion, a modified NELP circuit preserved hepatocyte architecture, recovered synthetic functions, and hepatobiliary parameters of ECD livers without additional injuries to the grafts. This approach has the potential to increase the donor pool for clinical transplantation. Liver Transplantation 22 979–993 2016 AASLD
Modelling internal nitridation in an alumina‐forming austenitic stainless steel
Authors: Elger R. , Magnusson H. , Frisk K.
Published: March 2016

An austenitic alumina forming stainless steel was exposed in a nitriding atmosphere comprising 5 vol% H2/N2 for 100 and 1000 h. After 100 h, the sample displayed aluminium nitrides down to 450 μm and chromium nitrides down to 200 μm. Thermodynamic equilibrium calculations and kinetic modelling of the system to simulate 100 h of exposure time were performed using the software ThermoCalc 4.1 including DICTRA. The order of appearance of nitrides in the sample starting from the surface can be understood from the thermodynamic equilibria as well as from results of kinetic modelling. However, the nitridation depth predicted by the kinetic modelling, was larger than experimentally observed, and the cubic chromium nitride predicted to be present on the surface was not detected in the exposed sample. One difference between model and experiment was a thin oxide layer present on the surface of the sample. As this oxide layer can decrease the inwards flux of nitrogen, attempts were made to describe the effects of this layer in the model. The model was also used for qualitative comparison of varying alloy compositions, temperatures and initial nitrogen contents of the matrix.
Effect of copper alloying addition on the electrochemical corrosion behaviour of Fe3Al intermetallic in sulphuric acid solution
Authors: Rosalbino F. , Carlini R. , Zanicchi G. , Scavino G.
Published: March 2016

The effect of Cu alloying addition on the corrosion resistance of iron aluminide Fe3Al has been investigated. In this work, the corrosion behaviour of Fe3Al‐5Cu (at%) alloys has been assessed by open circuit potential, potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) measurements carried out in a 0.5 M H2SO4 solution, without stirring and in contact with the air. For comparison, the electrochemical tests have also been performed on Fe3Al intermetallic. The obtained electrochemical results indicate that iron aluminide Fe3Al‐5Cu exhibits superior corrosion resistance as compared to Fe3Al. This improvement may be ascribed to the formation of a copper‐enriched surface layer which shows higher protective effectiveness than that formed on Fe3Al intermetallic.
Polyphosphazene Based Star‐Branched and Dendritic Molecular Brushes
Authors: Henke Helena , Posch Sandra , Brüggemann Oliver , Teasdale Ian
Published: March 2016

A new synthetic procedure is described for the preparation of poly(organo)phosphazenes with star‐branched and star dendritic molecular brush type structures, thus describing the first time it has been possible to prepare controlled, highly branched architectures for this type of polymer. Furthermore, as a result of the extremely high‐arm density generated by the phosphazene repeat unit, the second‐generation structures represent quite unique architectures for any type of polymer. Using two relativity straight forward iterative syntheses it is possible to prepare globular highly branched polymers with up to 30 000 functional end groups, while keeping relatively narrow polydispersities (1.2–1.6). Phosphine mediated polymerization of chlorophosphoranimine is first used to prepare three‐arm star polymers. Subsequent substitution with diphenylphosphine moieties gives poly(organo)phosphazenes to function as multifunctional macroinitiators for the growth of a second generation of polyphosphazene arms. Macrosubstitution with Jeffamine oligomers gives a series of large, water soluble branched macromolecules with high‐arm density and hydrodynamic diameters between 10 and 70 nm.

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Gamma knife radiosurgery in movement disorders: Indications and limitations
Authors: Higuchi Yoshinori , Matsuda Shinji , Serizawa Toru
Published: March 2016

Functional radiosurgery has advanced steadily during the past half century since the development of the gamma knife technique for treating intractable cancer pain. Applications of radiosurgery for intracranial diseases have increased with a focus on understanding radiobiology. Currently, the use of gamma knife radiosurgery to ablate deep brain structures is not widespread because visualization of the functional targets remains difficult despite the increased availability of advanced neuroimaging technology. Moreover, most existing reports have a small sample size or are retrospective. However, increased experience with intraoperative neurophysiological evaluations in radiofrequency thalamotomy and deep brain stimulation supports anatomical and neurophysiological approaches to the ventralis intermedius nucleus. Two recent prospective studies have promoted the clinical application of functional radiosurgery for movement disorders. For example, unilateral gamma knife thalamotomy is a potential alternative to radiofrequency thalamotomy and deep brain stimulation techniques for intractable tremor patients with contraindications for surgery. Despite the promising efficacy of gamma knife thalamotomy, however, these studies did not include sufficient follow‐up to confirm long‐term effects. Herein, we review the radiobiology literature, various techniques, and the treatment efficacy of gamma knife radiosurgery for patients with movement disorders. Future research should focus on randomized controlled studies and long‐term effects. © 2016 International Parkinson and Movement Disorder Society
Surface effect on nano piezoelectric energy harvester based on flexural mode
Authors: Fan Tao , Yang Lihong
Published: March 2016

In the present work, a nanoscale piezoelectric beam is developed as an energy harvester. The proposed model can convert the flexural vibration energy to the electric energy. Based on the surface effect theory, the nano beam is considered to be a composite structure with a core and two surface layers. The analytical expressions of the model are given, and the numerical calculations are conducted. Results show that the surface effect has important influences on the performances of the energy harvester. The output power is sensitive to the surface elastic constant and surface piezoelectric constant. The coupling effects of the core and surface material constants are examined. The physical dimension of the piezoelectric beam can also affect the power density. This paper presents the possibility of applying the nanoscale piezoelectric beam to the energy harvester. POLYM. COMPOS., 39:936–941, 2018. © 2016 Society of Plastics Engineers
Molecular mechanism leading to memory effect of mesomorphic isotactic polypropylene
Authors: Li Xiangyang , Liu Yanping , Tian Xingyou , Cui Kunpeng
Published: March 2016

In this study, memory effect of mesomorphic isotactic polypropylene (iPP) was investigated using polarized optical microscope and small‐angle X‐ray scattering. Differing from classical memory effect, mesomorphic iPP melt had a higher growth rate and a higher memory temperature. The relative growth rate increased with increasing crystallization temperature. Lauritzen–Hoffman plots indicated that the increased growth rate arose from reduced surface nucleation barrier. The highest memory temperature was estimated to be 185 °C, which was close to the equilibrium melting point of iPP crystal. Additionally, Small‐angle X‐ray scattering measurements showed that a liquid crystal layer might exist between lamellar and amorphous layers. Based on above results, a crystallization model was proposed. In the mesomorphic iPP melt, there exist aggregates structurally similar to β phase except α‐phase crystal residuals, which cannot act as nucleation sites or transform to β crystal through surface nucleation. The only way for the aggregate is to transform to α crystal during crystal growth. The aggregate decreases the surface nucleation barrier and promotes the helical growth, leading to higher growth rate. Only when the aggregate relaxes to polymer coils through thickening at a higher temperature, can the memory effect be erased. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 1573–1580
Frictional behaviors of three kinds of nanotextured surfaces
Authors: Wu Chunxia , Jia Junhong , Che Hongwei , Mu Jingbo , Zhao Shufeng , Zhang Xiaoliang
Published: March 2016

Nanodot‐textured surface, nanorod‐textured surface and nanocomposite‐textured surface were prepared by the hydrothermal technique and successive ion layer absorption and reaction technique. The adhesion and friction properties of the three kinds of nanotextured surfaces were investigated using an atomic force microscope colloidal probe. Experimental results revealed that the nanorod‐textured surface and nanocomposite‐textured surface can significantly reduce adhesive and friction forces compared with a nanodot‐textured surface. The main reason for this phenomenon was that the nanorod and nanocomposite textures can reduce contact area between the sample surface and the colloidal probe. The effects of surface root mean square roughness, applied load and sliding velocity on the adhesion and friction behaviors of the nanotextured surfaces were investigated. The adhesive and friction forces of the nanotextured surfaces decreased with the increasing surface root mean square roughness. Compared with the nanocomposite‐textured surface, the nanorod‐textured surface has better adhesion and frictional performance. Copyright © 2016 John Wiley & Sons, Ltd.
Influence of Surface Modifications on the Spatiotemporal Microdistribution of Quantum Dots In Vivo
Authors: Nekolla Katharina , Kick Kerstin , Sellner Sabine , Mildner Karina , Zahler Stefan , Zeuschner Dagmar , Krombach Fritz , Rehberg Markus
Published: March 2016

For biomedical applications of nanoconstructs, it is a general prerequisite to efficiently reach the desired target site. In this regard, it is crucial to determine the spatiotemporal distribution of nanomaterials at the microscopic tissue level. Therefore, the effect of different surface modifications on the distribution of microinjected quantum dots (QDs) in mouse skeletal muscle tissue has been investigated. In vivo real‐time fluorescence microscopy and particle tracking reveal that carboxyl QDs preferentially attach to components of the extracellular matrix (ECM), whereas QDs coated with polyethylene glycol (PEG) show little interaction with tissue constituents. Transmission electron microscopy elucidates that carboxyl QDs adhere to collagen fibers as well as basement membranes, a type of ECM located on the basolateral side of blood vessel walls. Moreover, carboxyl QDs have been found in endothelial junctions as well as in caveolae of endothelial cells, enabling them to translocate into the vessel lumen. The in vivo QD distribution is confirmed by in vitro experiments. The data suggest that ECM components act as a selective barrier depending on QD surface modification. For future biomedical applications, such as targeting of blood vessel walls, the findings of this study offer design criteria for nanoconstructs that meet the requirements of the respective application.
New probabilistic risk assessment of ethylhexyl methoxycinnamate: Comparing the genotoxic effects of trans‐ and cis‐EHMC
Authors: Nečasová Anežka , Bányiová Katarína , Literák Jaromír , Čupr Pavel
Published: March 2016

Ethylhexyl methoxycinnamate (EHMC) is a widely used UV filter present in a large number of personal care products (PCPs). Under normal conditions, EHMC occurs in a mixture of two isomers: trans‐EHMC and cis‐EHMC in a ratio of 99:1. When exposed to sunlight, the trans isomer is transformed to the less stable cis isomer and the efficiency of the UV filter is reduced. To date, the toxicological effects of the cis‐EHMC isomer remain largely unknown. We developed a completely new method for preparing cis‐EHMC. An EHMC technical mixture was irradiated using a UV lamp and 98% pure cis‐EHMC was isolated from the irradiated solution using column chromatography. The genotoxic effects of the isolated cis‐EHMC isomer and the nonirradiated trans‐EHMC were subsequently measured using two bioassays (SOS chromotest and UmuC test). In the case of trans‐EHMC, significant genotoxicity was observed using both bioassays at the highest concentrations (0.5 ‐ 4 mg mL−1). In the case of cis‐EHMC, significant genotoxicity was only detected using the UmuC test at concentrations of 0.25 ‐ 1 mg mL−1. Based on these results, the NOEC was calculated for both cis‐ and trans‐EHMC, 0.038 and 0.064 mg mL−1, respectively. Risk assessment of dermal, oral and inhalation exposure to PCPs containing EHMC was carried out for a female population using probabilistic simulation and by using Quantitative in vitro to in vivo extrapolation (QIVIVE). The risk of cis‐EHMC was found to be ∼1.7 times greater than trans‐EHMC. In the case of cis‐EHMC, a hazard index of 1 was exceeded in the 92nd percentile. Based on the observed differences between the isomers, EHMC application in PCPs requires detailed reassessment. Further exploration of the toxicological effects and properties of cis‐EHMC is needed in order to correctly predict risks posed to humans and the environment. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 569–580, 2017.
Dynamic recrystallisation of ice aggregates during co-axial viscoplastic deformation: a numerical approach
Authors: LLORENS MARIA-GEMA , GRIERA ALBERT , BONS PAUL D. , ROESSIGER JENS , LEBENSOHN RICARDO , EVANS LYNN , WEIKUSAT ILKA
Published: March 2016

Results of numerical simulations of co-axial deformation of pure ice up to high-strain, combining full-field modelling with recrystallisation are presented. Grain size and lattice preferred orientation analysis and comparisons between simulations at different strain-rates show how recrystallisation has a major effect on the microstructure, developing larger and equi-dimensional grains, but a relatively minor effect on the development of a preferred orientation of c-axes. Although c-axis distributions do not vary much, recrystallisation appears to have a distinct effect on the relative activities of slip systems, activating the pyramidal slip system and affecting the distribution of a-axes. The simulations reveal that the survival probability of individual grains is strongly related to the initial grain size, but only weakly dependent on hard or soft orientations with respect to the flow field. Dynamic recrystallisation reduces initial hardening, which is followed by a steady state characteristic of pure-shear deformation.
Predicting the amount of urea nitrogen recycled and used for anabolism in growing cattle
Authors: EISEMANN J. H. , TEDESCHI L. O.
Published: March 2016

In ruminants, urea nitrogen (N) produced by the liver and recycled to the gastrointestinal tract (GIT) provides a source of N for microbial growth and also conserves N. In this respect, it buffers the dietary supply of N available for microbial growth and microbial protein supply. The equation for recycled N in the National Research Council's (NRC 1996, 2000) beef model is based on relationships between ruminal ammonia and plasma urea N concentrations. The objective of the current paper was to estimate recycled N available for anabolism (i.e., urea N used for anabolism, UUA) using available kinetic data. A meta-analysis was conducted using results reported in nine publications that measured urea N kinetics using the dual-labelled urea technique in growing cattle. Diets used in these experiments were predominantly forage-based. Urea production was linearly related to N intake (NI, g/day). Growing cattle converted 74·5% of the incremental NI to urea N. As NI increased, a smaller proportion of the urea produced was recycled to the GIT. On average, 54·4% of the urea N recycled to the GIT was used for anabolism; however, this percentage was not constant. As NI or dietary crude protein (CP) increased (g/kg dry matter, DM), proportionately less of the urea produced was used for anabolism. Nonlinear equations were developed to predict UUA based on NI or dietary CP in the current database and simulated at 5 or 10 kg of daily DM intake (DMI) over the same range of NI (g/day) and therefore, for diets differing in CP content (g/kg DM). The equation based on NI had a quadratic behaviour and the same estimated UUA for both levels of DMI. The equation based on CP showed a relatively small increase in UUA at low DMI and increased UUA at the higher DMI as NI increased. For both equations and both DMI, the pattern suggested a limit to use of recycled N for anabolism.
Introduction: special issue on age effects in child language acquisition
Authors: BLOM ELMA , PARADIS JOHANNE
Published: March 2016

While age of acquisition effects have been researched extensively in adult second language (L2) acquisition, there is less research focused on examining age of acquisition effects in child language learners. Importantly, for child learners, delays in exposure to language can occur not only for a second but also for a first language (L1). In regard to delays in exposure, it is a widespread assumption that these are detrimental to language outcomes, and that younger is always better for successful language learning. One of the aims of this special issue was to take a closer look at the evidence for this assumption with respect to language learning within the childhood years, both for delayed L1 and L2 exposure.
The Relationships Between Various Techniques for Obtaining Proper Motions
Authors: Murray C. A.
Published: March 2016

In many problems of galactic kinematics we need to know the proper motions of faint stars, as well as bright stars, within some well-defined reference frame. Generally speaking, the accuracy required is greater for faint stars on account of their larger distances. Techniques at present used for determining proper motions vary according to apparent magnitude, and it is clearly desirable that all methods should give results which are capable of reduction to a common frame.
The Calculation of the Nutations
Authors: Vicente R. O.
Published: March 2016

It is well known that the knowledge of precession and nutation is essential for the computation of astronomical coordinates and the comparison of values obtained at different dates. It is therefore important to compute the nutations from the best available observations.

Unfortunately, there are not many long series of reliable observations that can be used for the calculation of the several nutations. Nowadays, we need more accurate values and, therefore, it is fundamental to have observations reduced in an homogeneous way. For this purpose, Commission 19 (Rotation of the Earth) set up a ‘Working Group on Pole Coordinates’, during the last IAU meeting in 1970 (Vicente, 1972), with the objective of reducing the 70 years of variation of latitude observations done by the International Latitude Service (called the International Polar Motion Service at the present time) that constitute a remarkable set of astronomical data. It is expected to obtain more reliable values for the coordinates of the pole and be able to calculate the nutations.

The Working Group on Pole Coordinates is transferring to punched cards all the observations registered in the original observation books and that involves nearly 2 million cards. This work has been hampered by financial difficulties, but it should be supported by the international astronomical community in order to obtain the best results from so many years of observations, done by international cooperation.

The theoretical researches done in the last decades have shown that the values of the nutations depend on the structure of the Earth (Jeffreys and Vicente, 1957). Lately, the researches done in seismology have resulted in a better knowledge about the structure of the Earth, leading to the setting up of many Earth models due to the availability of computers. This fact has led to the situation where one cannot propose better theoretical values for the nutations because they depend on the model adopted for the structure of the Earth.
The Principle of Least Interaction Action
Authors: Ovenden M. W.
Published: March 2016

The intuitive notion that a satellite system will change its configuration rapidly when the satellites come close together, and slowly when they are far apart, is generalized to ‘The Principle of Least Interaction Action’, viz. that such a system will most often be found in a configuration for which the time-mean of the action associated with the mutual interaction of the satellites is a minimum. The principle has been confirmed by numerical integration of simulated systems with large relative masses. The principle lead to the correct prediction of the preference, in the solar system, for nearly-commensurable periods. Approximate methods for calculating the evolution of an actual satellite system over periods ˜ 109 yr show that the satellite system of Uranus, the five major satellites of Jupiter, and the five planets of Barnard’s star recently discovered, are all found very close to their respective minimum interaction distributions. Applied to the planetary system of the Sun, the principle requires that there was once a planet of mass ˜ 90 Mθ in the asteroid belt, which ‘disappeared’ relatively recently in the history of the solar system.
Bursting X-Ray Sources: A Theoretical Framework for Accretion Models
Authors: Lamb F.K. , Fabian A.C. , Pringle J.E. , Lamb D. Q.
Published: March 2016

We consider spherically symmetric accretion flow onto a strongly magnetized neutron star. We show that, under certain conditions, the flow is intermittent and that the resultant accretion luminosity (X-rays) from the stellar surface is akin to that observed in the bursting X-ray sources. We investigate the properties of such burst flows under a variety of conditions, in the hopes of providing a basic theoretical framework on which realistic models of the observed bursting sources can be built. This work was supported in part by NSF Grant PHY75-08790.
A New Temperature Scale for B Stars Based on OAO-2 Data
Authors: Lesh Janet Rountree
Published: March 2016

The empirical temperature scale of Code, Davis, Bless, and Hanbury Brown has been recalibrated in terms of an ultraviolet color derived from OAO-2 photometry, and mean temperatures have been computed for MK spectral types from O9 to A0. The dereddened color (1910-V)o was chosen as a temperature indicator because it is not strongly affected by lines or continuum edges. This parameter was computed for 16 stars with spectral types earlier than A2, luminosity classes III-V, and normal spectra, whose temperatures had been measured by Code et al. Plotting 8eff against (1910-V)o, we obtained the relation.θeff = 0.111 (1910-V)o + 0. 565. Next, the quantity (1910-V) was computed for over 150 stars in the same spectral-type range which had been observed by OAO-2, and a mean value was obtained for each spectral type. (Class III stars were excluded for types B5 and later because they were found to be systematically redder than classes IV and V - possibly an evolutionary effect.) Finally, the mean values of (1910-V)o were converted to effective temperatures using the formula given above. The resulting temperature scale is in good agreement with the scales of Morton and Adams, Schild, Peterson and Oke, and Code et al. for types B3 and later, but between types B0.5 and B2 the new scale and the Code scale are significantly hotter than the others. A particular application of the new calibration is the determination of small temperature changes occurring in early-type variable stars, since in this case the large and uncertain reddening correction drops out. For the β Cephei variables δ Cet and γ Peg, we obtained ΔT = 550°K and 185°K, respectively. This work was supported by the National Aeronautics and Space Administration under grants NSG 5004 and NSG 5069.
On the Spottedness and Magnetic Field of T Tau-Type Stars
Authors: Gershberg R. E.
Published: March 2016

There are several observations that suggest the existence of surface heterogeneities on the T Tau-type stars. Firstly Dr. Ismailov from Shemakha has found strong variations of emission line profiles for 5-10 minutes: 2-component profiles become 3 or 1 component and vice-versa. The results were confirmed recently in the Sternberg Institute. Secondly, variations of polarization degree and relative intensities in the IR calcium triplet were found when the stellar brightness were being constant. Then, the relative intensities of the Ca triplet are not equal to what must be expected for both optically thin or thick but homogeneous emission regions. On the basis of the data Petrov and Sheberbakov from Crimean Observatory have proposed that T Tau stars have active regions with strong magnetic fields similar to stellar ones: they can give noticeable heterogeneities for calcium emission, for polarization effects in dust envelopes and local processes for profile variations. The existence of rather strong and local magnetic fields on T Tauri stars may give a key for explaining the mysteries of these variables. Small variations of strong magnetic fields on stars with a convective zone can give a new mechanism for stellar variability. As it is known, only a quarter of the energy flux that reaches the bottom of the convective zone, is emitted from a sunspot in form of light and the main part of the energy escapes in form of hydromagnetic waves. Then, the sunspot exists if the field is not less than 1 kilogauss. Therefore the field acts as a relay: if the field is low we have light, if the field is strong we have mainly hydromagnetic waves. The transition from low to high field may occupy only a small part of the whole field range. The field variations on T Tau stars can give strong brightness variations without additional energy sources but only by magnetic relay operation. I hope that this scheme gives a possibility to explain a set of features of T Tau stars (such as their high ratio of chromospheric to photospheric radiation, IR excesses, the nature of their flares) as well as main features of FU Ori-type flares.
The Intergalactic Medium
Authors: Field George B.
Published: March 2016

Observations of Lyman-α absorption show that any gas present in the space between clusters of galaxies must be hot, and x-ray observations indicate that there may be present gas whose temperature at low redshifts is 4 × 108 K and whose density is about half the critical value for cosmology. The interpretation of these observations is reviewed, and difficulties with proposed heating mechanisms are emphasized.
Supernovae: The Ultimate Instability
Authors: Kirshner Robert P.
Published: March 2016

Observed properties of supernovae and of very young supernova remnants provide important clues to answer the question, “which stars become supernovae?” There are three general lines of evidence (l) the statistics of supernovae, (2) the physical state of supernovae near maximum light, and (3) the chemistry of young supernova remnants. These lines of evidence appear to be converging on the view that all the supernova explosions we see, whether Type I or Type II, arise from the destruction of young massive stars.

It is important to note that supernovae fall into two distinct spectroscopic classes: Type I which does not show strong hydrogen lines, and Type II in which hydrogen emission and absorption is prominent (Oke and Searle, 1974). It is possible that the stellar progenitors of these two types are very different, but recent evidence suggests that the similarities in the properties of the two classes are more important.