bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility Study for Transforming Spectral and Instrumental Artifacts for Multivariate Calibration Maintenance
Authors: Ottaway Joshua , Kalivas John H.
Published: March 2015

Frequently, a spectral-based multivariate calibration model formed on a particular instrument (primary) needs to predict samples measured on other (secondary) instruments of the same spectral type. This situation is often referred to as calibration maintenance or transfer. A new calibration maintenance approach is developed in this paper using spectral differences between instruments. In conjunction with a sample weighting scheme, spectral differences are piecewise (wavelength window) or full spectrum fitted with modeling terms (correction terms) such as polynomials and derivatives. Results demonstrating the potential usefulness of the new method using a near infrared (NIR) benchmark dataset are presented in this paper. The process does not need a standardization sample set measured in the primary condition. Thus, the new approach is a “hybrid” between the popular methods of extended inverted multiplicative signal correction (EISC) and direct standardization (DS) or piecewise DS (PDS). It is found that prediction errors reduce for samples measured in the secondary condition compared to those based on no calibration transfer. Prediction errors are also comparable to those from a full calibration in the secondary condition. In addition to instrument correction, an extension of the new approach is discussed (but not tested) for predicting new samples changing over time due to new chemical, physical, and environmental measurement conditions including individually or combinations of temperature, sample particle size, and new spectrally responding species.
Measurements of Metal Alkylamide Density during Atomic Layer Deposition Using a Mid-Infrared Light-Emitting Diode (LED) Source
Authors: Maslar James E. , Hoang John , Kimes William A. , Sperling Brent A.
Published: March 2015

A nondispersive infrared (NDIR) gas analyzer that utilizes a mid-infrared light emitting diode (LED) source was demonstrated for monitoring the metal alkylamide compound tetrakis(dimethylamido) titanium (TDMAT), Ti[N(CH3)2]4. This NDIR gas analyzer was based on direct absorption measurement of TDMAT vapor in the C–H stretching spectral region, a spectral region accessed using a LED with a nominal emission center wavelength of 3.65 μm. The sensitivity of this technique to TDMAT was determined by comparing the absorbance measured using this technique to the TDMAT density as determined using in situ Fourier transform IR (FT-IR) spectroscopy. Fourier transform IR spectroscopy was employed because this technique could be used to (1) quantify TDMAT density in the presence of a carrier gas (the presence of which precludes the use of a capacitance manometer to establish TDMAT density) and (2) distinguish between TDMAT and other gasphase species containing IR-active C–H stretching modes (allowing separation of the signal from the LED-based optical system into fractions due to TDMAT and other species, when necessary). During TDMAT-only delivery, i.e., in the absence of co-reactants and deposition products, TDMAT minimum detectable molecular densities as low as ≈∼4 × 1012 cm−3 were demonstrated, with short measurement times and appropriate signal averaging. Reactions involving TDMAT often result in the evolution of the reaction product dimethylamine (DMA), both as a thermal decomposition product in a TDMAT ampoule and as a deposition reaction product in the deposition chamber. Hence, the presence of DMA represents a significant potential interference for this technique, and therefore, the sensitivity of this technique to DMA was also determined by measuring DMA absorbance as a function of pressure. The ratio of the TDMAT sensitivity to the DMA sensitivity was determined to be ≈∼6.0. To further examine the selectivity of this technique, measurements were also performed during atomic layer deposition (ALD) of titanium dioxide using TDMAT and water. During ALD, potential interferences were expected from the evolution of DMA due to deposition reactions and the deposition on the windows of species containing IR-active C–H stretching modes. It was found that the interfering effects of the evolution of DMA and deposition of species on the windows corresponded to a maximum of only ≈∼6% of the total observed TDMAT density. However, this level of interference likely is relatively low compared to a typical chemical vapor deposition process in which co-reactants are introduced into the chamber at the same time.
Queering stars: Fan play and capital appropriation in the age of digital media
Authors: Kwon Jungmin
Published: March 2015

Among many different forms of celebrity fandom, this article pays attention to fan-produced novels, that is, fanfic. In Korea, fanfic indicates a homoerotic story between two members of a singing group in real life that fan authors create and circulate online, which this article conceptualizes as queering stars. Thanks to the development of digital media, the fanfic subculture flourished, thereby capturing the eyes of the entertainment industry. This article investigates the ways in which media professionals and celebrities make use of and commercialize fans’ queering stars with a case of SM Entertainment (SME), a leading entertainment company in Korea. It argues that digitally empowered fans are repositioned as a pivotal axis in the contemporary mediascape, and the entertainment sector observes and exploits fans’ culture more than ever. This article concludes that the relationship between fans and industry is not unilateral in the digitalized and capitalized age. Rather, it is inter-animating and multi-layered, and interaction is ongoing and recurring.
O planeamento de emergência de protecção civil em Portugal
Authors: Fonseca Teresa Cravo da , Mendes José Manuel
Published: March 2015

Com a introdução em 2008 de novas alterações legislativas no âmbito do quadro dos critérios e normas técnicas para a elaboração e operacionalização de planos de emergência de protecção civil, foi proposto um novo paradigma de planeamento de emergência e uma nova estratégia de âmbito nacional. Com base em entrevistas aprofundadas a técnicos, operacionais, dirigentes, ex-dirigentes e investigadores envolvidos no processo, procede-se a uma análise crítica e reflexiva sobre o processo de implementação da “segunda geração” de planos de emergência de protecção civil.
Segurança e gestão do risco no turismo de natureza
Authors: Neves Daniel Márcio Fernandes
Published: March 2015

O risco é um conceito cada vez mais presente no turismo, sobretudo associado ao comportamento humano, o qual torna mais evidente a vulnerabilidade de um determinado território. As questões de segurança (Safety and Security) desempenham um papel vital nas actividades desenvolvidas pelas pessoas nas viagens e nas estadas em locais situados fora do seu enquadramento habitual.Tendo-se constatado que os eventos catastróficos são responsáveis pela maioria das crises turísticas vividas nos últimos tempos, surge a necessidade de investigar a gestão do risco no turismo, suas consequências e antecedentes de forma mais profunda, nomeadamente em territórios insulares.
A Oscilação do Atlântico Morte (NAO) e riscos climáticos em Coimbra durante o inverno entre 1950 e 2010
Authors: Mateus Carla , Cunha Lúcio
Published: March 2015

Existe uma relação entre as fases da NAO e as manifestações de risco climático no Inverno em Coimbra entre 1950 e 2010. Verificaram-se períodos com maiores quantitativos pluviométricos, maiores caudais mensais e maior ocorrência de cheias, o que correspondeu a fases negativas da NAO. Em oposição, durante as fases positivas registou-se um abaixamento das temperaturas mínimas, maior número de dias com temperaturas negativas, em Coimbra, e maior ocorrência de ondas de frio, na Região Centro, entre 1983 e 2009.
The one-dimensional model for d-cones revisited
Authors: Olbermann Heiner
Published: March 2015

A d-cone is the shape one obtains when pushing an elastic sheet at its center into a hollow cylinder. In a simple model, one can treat the
elastic sheet in the deformed configuration as a developable surface with a singularity at the “tip” of the cone.
In this approximation, the renormalized elastic energy is
given by the bending energy density integrated over some annulus in the
reference configuration. The thus defined variational problem depends on the
indentation

h

${{h}}$

of the sheet into the cylinder.
This model has been investigated before in the physics literature;
the main motivation for the present paper is to give a rigorous version of some of the results achieved there via formal arguments.
We derive the Gamma-limit of the energy functional as

h

${{h}}$

is sent to
0. Furthermore, we analyze the minimizers of the limiting functional, and list a number of necessary conditions that they have to fulfill.
Vertical or Horizontal: Endogenous Merger Waves in Vertically Related Industries
Authors: Yao Zhiyong , Zhou Wen
Published: March 2015

Endogenous merger waves are studied in vertically related industries where firms may engage in both vertical and horizontal mergers. It is shown that whether and how firms merge depends crucially on the balance between vertical and horizontal externalities, and the balance between upstream and downstream competition. Furthermore, firms may merge with or without any fundamental change in the underlying economic conditions.
Joint Access Control Based on Access Ratio and Resource Utilization for High-Speed Railway Communications
Authors: Zhou Yuzhe , Ai Bo
Published: March 2015

The fast development of high-speed rails makes people’s life more and more convenient. However, provisioning of quality of service of multimedia applications for users on the high-speed train is a critical task for wireless communications. Therefore, new solutions are desirable to be found to address this kind of problem. Current researches mainly focus on providing seamless broadband wireless access for high-speed mobile terminals. In this paper, an algorithm to calculate the optimal resource reservation fraction of handovers is proposed. A joint access control scheme for high-speed railway communication handover scenario is proposed. Metrics of access ratio and resource utilization ratio are considered jointly in the analysis and the performance evaluation. Simulation results show that the proposed algorithm and the scheme improve quality of service compared with other conventional schemes.
Rapid transfer of overexpressed integral membrane protein from the host membrane into soluble lipid nanodiscs without previous purification
Authors: Shirzad-Wasei Nazhat , van Oostrum Jenny , Bovee-Geurts Petra H.M. , Kusters Lisanne J.A. , Bosman Giel J.C.G.M. , DeGrip Willem J.
Published: March 2015

Structural and functional characterization of integral membrane proteins in a bilayer environment is strongly hampered by the requirement of detergents for solubilization and subsequent purification, as detergents commonly affect their structure and/or activity. Here, we describe a rapid procedure with minimal exposure to detergent to directly assemble an overexpressed integral membrane protein into soluble lipid nanodiscs prior to purification. This is exemplified with recombinant his-tagged rhodopsin, which is rapidly extracted from its host membrane and directly assembled into membrane scaffold protein (MSP) nanodiscs. We further demonstrate that, even when the MSP was his-tagged as well, partial purification of the rhodopsin-nanodiscs could be achieved exploiting immobilized-metal chromatography. Recoveries of rhodopsin up to 80% were achieved in the purified nanodisc fraction. Over 95% of contaminating membrane protein and his-tagged MSP could be removed from the rhodopsin-nanodiscs using a single Ni2+-affinity chromatography step. This level of purification is amply sufficient for functional studies. We provide evidence that the obtained rhodopsin-nanodisc preparations are fully functional both photochemically and in their ability to bind the cognate G-protein.
Jeffrey O’Connell and the Market in Tort Claims
Authors: Sebok Anthony J.
Published: March 2015

This article examines a transitional period in Jeffrey O’Connell’s long and productive career as an observer and critic of the American civil justice system. By the early 1970’s O’Connell had begun to abandon enterprise liability as a solution to the waste and undercompensation he saw in the tort system. Eventually O’Connell would develop solutions that focused on constraining plaintiffs’ attorneys, and less on no-fault compensation. Before reaching this point, O’Connell proposed a no-fault insurance scheme that would be paid for by fault-based tort litigation. This proposal, which he called “elective first party no-fault insurance” (“EFPI”) is the focus of this article. In EFPI tort suits would not disappear, and damages would not be limited, but litigation would be conducted by insurers who had been assigned their insured’s lawsuits. This article describes how this novel tort reform would work, and explores the theoretical assumptions upon which it is based. One assumption in particular, which is examined, is that a market in tort litigation could be socially efficient if the right sort of plaintiffs’ lawyers were recruited to conduct it. Finally, this article points out that O’Connell called for the repeal of champerty laws at least a decade before many other modern legal academics focused on the potential of a market in litigation.
Litter size and basic diet of brown bears (Ursus arctos, Carnivora) in northeastern Turkey
Authors: Ambarlı Hüseyin
Published: March 2015

Brown bears (
Asymmetric calixarene derivatives as potential hosts in chiral recognition processes
Authors: Maftei Catalin V. , Fodor Elena , Jones Peter G. , Franz M. Heiko , Davidescu Corneliu M. , Neda Ion
Published: March 2015

New chiral derivatives of 15,35,55,75-tetra-tert-butyl-1,3,5,7(1,3)-tetrabenzenacyclooctaphane-12,32,52,72-tetraol [(1); tert-butyl-calix[4]-arene] were synthesized by coupling modified chiral quinuclidines derived from the natural-product-based alkaloids quincorine and quincoridine with the calix[4]arene1via either an ester bond or an amide bond. X-ray analyses of two products were performed. Applications of the products in asymmetric catalytic hydrogen transfer reactions are described. A protocol is presented to multi-substitute calix[4]arene at the methylene bridges, resulting in, e.g., 2,6-carboxyl-all-tert-butyl all-methoxy-calix[4]arene.
Correlation of trisomy 13 with atelencephalic aprosencephaly
Authors: Kitova Tanya , Kitov Borislav , Cheikh Nahed Ben , Gaigi Soumeya Siala
Published: March 2015

A rare phenotype-genotype correlation of atelencephalic aprosencephaly in a fetus with free trisomy 13 karyotype, obtained by pregnancy termination for holoprosencephaly during the 26th gestational week, is presented. Lack of cerebral hemispheres and presence of rudimentary diencephalon, brain stem and hypoplastic cerebellum were revealed. Agenesis of the eyeball, of the optic nerve and of the pyramids of the medulla oblongata was established. Skull and face examination found craniostenosis, microcephaly, cella turcica agenesis, cyclopia, cleft palate and nose agenesis.The correlation between the most common karyotype of trisomy 13 and the very rare brain abnormality atelencephalic aprosencephaly suggests that the study of parental karyotype is desirable to inform parents about its accidental and non-hereditary nature in a probable future pregnancy.
A decomposition approach for the discrete-time approximation of FBSDEs with a jump
Authors: Kharroubi Idris , Lim Thomas
Published: March 2015

We are concerned with the discretization of a solution of a forward-backward stochastic differential equation (FBSDE) with a jump process depending on the Brownian motion. In this paper, we study the cases of Lipschitz generators and the generators with a quadratic growth with respect to the variable z. We propose a recursive scheme based on a general existence result given in the companion paper [Journal of Theoretical Probability 27 (2014), 683–724] and we study the error induced by the time discretization. We prove the convergence of the scheme when the number of time steps n goes to infinity. Our approach allows to get a convergence rate similar to that of schemes of Brownian FBSDEs.
A novel method to prioritize RNAseq data for post-hoc analysis based on absolute changes in transcript abundance
Authors: McNutt Patrick , Gut Ian , Hubbard Kyle , Beske Phil
Published: March 2015

The use of fold-change (FC) to prioritize differentially expressed genes (DEGs) for
Temperature and humidity dependent investigations on paulingite
Authors: Bieniok Anna , Brendel Uwe , Park SoHyun
Published: March 2015

Paulingite (PAU-Ca), a rare, natural small-pore zeolite was dehydrated by cooling in a flow of dry N2 gas and the structural changes of the partly dehydrated phase were analysed at 100 K using synchrotron diffraction. The LT-dehydration led to a symmetry reduction from space group

I
m

3
¯

m

$Im\bar 3m$

to

I

4
¯

3
m

$I\bar 43m$

accompanied by a cell volume decrease of 3.7% to cell constant 34.681(1) Å. The refinement converged with residuals of 6.07% (R1) and 16.46% (wR2). Structural changes affect the d8r-units (double eight-rings) with elliptical deformations of the single 8-rings aligned perpendicular to each other and the α-cage (great rhombicuboctahedron) with a tetrahedral compression. The openings of the main channel system of the complex framework structure were reduced by 0.87 Å. The dehydration starts with hydrated Ca cations inside the medium-sized plg-cages accompanied by cation migrations. The study documents the high sensitivity of zeolites to changes in air humidity and the importance of understanding thermally induced and dehydration-induced transformations in zeolite materials.
Zur Rolle lokalisierter Zustände der Bethe-Goldstone-Gleichung
Authors: Lüders Gerhart
Published: March 2015

As recently pointed out by GOTTFRIED localized solutions of the BETHE-GOLDSTONE equation can possibly affect the consistency of the BRUECKNER treatment of the many body problem. In the present paper the same problem is taken up from a different point of view by indicating the place where an inconsistency occurs in the lowest order or in higher orders of the GOLDSTONE analysis. Localized states of pairs of particles “in nuclear matter” seem just as dangereous as those of more particles.
Über den Einfluß von Kohleabsorbern auf die Neutronenerzeugung in Blei durch kosmische Strahlung und die absolute Häufigkeit nuklearer Kaskaden in verschieden dicken Bleischichten
Authors: Sen Chaudhury P. K. , Pfotzer G.
Published: March 2015

Bei der Filterung der kernaktiven Komponente der kosmischen Strahlung mit festen Absorbern wurden von verschiedenen Autoren Übergangsmaxima der Sternhäufigkeit in der photographischen Emulsion gemessen. In der vorliegenden Arbeit wird untersucht, wie weit ein Zusammenhang ähnlicher Übergangseffekte der lokalen Neutronenproduktion mit den obigen Befunden behauptet werden kann. Es ergab sich, daß ein stark ausgeprägtes Maximum der Neutronenzählraten, welches ebenso wie ein Maximum der Sternhäufigkeit unter 9 bis 11 cm Kohlenstoff auftritt, vollständig auf die Streuung der Verdampfungsneutronen am Absorber zurückgeführt werden kann. Eine echte Erhöhung der Neutronenproduktion innerhalb ± 5% war nicht mehr nachweisbar. Die Intensität der Neutronen nimmt monoton mit der Schichtdicke, entsprechend einer Absorptionsschicht von 182 ± 30 g/cm2 ab.

Im Gegensatz hierzu wies die Abhängigkeit der integralen Häufigkeit nuklearer Kaskaden in verschieden dicken Bleischichten charakteristische Züge auf, welche auf einen reellen Zusammenhang mit den Übergangseffekten hindeuten, die in Kernspurplatten als Maxima der differentiell gemessenen Stern häufigkeit nachgewiesen wurden. — Durch Zählung von Neutronenkoinzidenzen konnte bei den Versuchen mit Kohleabsorbern der Störuntergrund entscheidend reduziert werden. Ferner erlaubte die simultane Zählung von Einzelneutronen und Koinzidenzen eine Absolutbestimmung der Kaskadenzahl in Blei ohne besondere Eichung der Zählanlage. Die nach dieser Methode ermittelte absolute Intensität der kernaktiven Komponente der K. S. stimmt mit den Angaben anderer Autoren befriedigend überein.
Messung der Atomwärme des Zinks zwischen 12 und 273°K
Authors: Eichenauer Walter , Schulze Martin
Published: March 2015

Die Atomwärme Cp wurde an einem 197 g schweren Zinkzylinder zwischen 12 und 273°K gemessen. Unter Verwendung der von BRONSON und WILSON 11 sowie von KEESOM und VAN DEN ENDE 1 angegebenen Cp-Werte wurde durch graphische Integration die Normalentropie des Zinks bei 25°C zu 9,94 CLAUSIUS bestimmt.
Ergebnisse der Tieftemperaturforschung
Authors: Clusius Klaus , Franzosini Paolo
Published: March 2015

Die Atom- und Elektronenwärme des Molybdäns und Wolframs wird zwischen 10°K und 273°K an zwei kompakten Versuchskörpern gemessen, die eine Reinheit von 99,99% aufweisen. Die neueren Angaben verschiedener Beobachter stimmen gut untereinander überein. Die Standardentropien für 25°C ergeben sich zu 6,83 Clausius für Molybdän und 7,83 Clausius für Wolfram. Der γ-Wert für die T proportionale Elektronenwärme ändert sich vom Heliumgebiet bis Zimmertemperatur nur wenig.

Die DEBYESchen Θ-Werte zeigen oberhalb von 100°K den für die Übergangsmetalle charakteristischen Abfall, wenn man zu ihrer Ermittlung von den direkt beobachteten Cv-Werten ausgeht. Konstante Θ g- Werte für das Gitter erhält man zwischen 100°K und Zimmertemperatur erst dann, wenn die Elektronenwärmen abgezogen werden. Diese Θg-Werte betragen bei beiden Elementen recht genau 84,3% des im T3-Gebiet gültigen Θg*-Wertes.
Protonenresonanzspektren von Cyclopentadien, Methylcyclopentadien, Cycloheptatrien und Trimethylsiliciumchlorid
Authors: Strohmeier Walter , Lombardi Erminio , Lemmon Richard M.
Published: March 2015

Es wurden mit Hilfe der kernmagnetischen Resonanzmethode die Protonenresonanzspektren von monomerem und dimerem Cyclopentadien und Methylcyclopentadien sowie von Cycloheptatrien und Trimethylsiliciumchlorid aufgenommen.

Die chemical shifts der Protonenresonanzen wurden unter Verwendung von Cyclohexan als „innerer Standard“ bestimmt.

Monomeres Cyclopentadien besitzt 2 scharfe Resonanzlinien, deren chemical shift δCH= +1,1 ppm und δCH
2= —2,5 ppm ist. Die 4 CH-Protonen sind äquivalent.

Das Spektrum von monomerem Methylcyclopentadien zeigt Hyperfeinstruktur. 3 Gruppen von Resonanzlinien, entsprechend den CH-, CH2- und CH3-Protonen, wurden beobachtet.

Die Dimerisation des monomeren Cyclupentadiens und Methylcyclopentadiens wurde durch Aufnahme der Protonenresonanzspektren zeitlich verfolgt.

Aus dem Spektrum des Cycloheptatriens folgt, daß die α-, β- und γ-Protonen nicht äquivalent sind.

Im Trimethylsiliciumchlorid ist die chemical shift der Protonenresonanz δCH
3= —4,8 ppm.

In Cyclohexan als Lösungsmittel war die chemical shift für Cyclopentadien und Methylcyclopentadien im Konzentrationsbereich x=0,2—0,8 (x=Molenbruch) von der Konzentration unabhängig.
Kernresonanzuntersuchungen an kristallinen Flüssigkeiten: Zur Frage des molekularen Ordnungszustandes in magnetisch geordneten kristallin-flüssigen Phasen vom smektischen Typ
Authors: Weber Karl-Heinz
Published: March 2015

In den kristallin-flüssigen, smektischen (bz-) Phasen des Azoxyphenol-di-p-n-heptyhäthers und des Azoxybenzoesäure-di-p-äthylesters wurden bei einer Feldstärke H0 = 7750 Gauß die Linienformen der magnetischen Protonenresonanzabsorption registriert und daraus die mittleren 2. Momente ΔH2 bestimmt. Sowohl aus der Temperaturabhängigkeit als auch aus der bei einer Drehung der Probe um eine senkrecht zum Magnetfeld gelegene Achse beobachteten Winkelabhängigkeit des 2. Moments erhält man Auskunft über die Winkelverteilung der Moleküllängsachsen im orientierenden Magnetfeld. In den smektischen Phasen beider Substanzen ist die „Mikro-Ordnung“, d. h. die Parallelorientierung der Moleküllängsachsen innerhalb kleiner Volumbereiche vollkommen, während die durch das Magnetfeld hervorgerufene „Makro-Orientierung“ der Probe unvollkommen ist; insbesondere wird am Azoxyphenol-heptyläther beim Übergang nematisch → smektisch eine Vergrößerung des Mikro-Ordnungsgrades S und eine Verkleinerung des Makro-Ordnungsgrades M beobachtet.
Ultramarin-Gelb II: Herstellung und Charakterisierung einer Rarität / Ultramarine-Yellow II: Preparation and Characterization of a Rarity
Authors: Köhler P. , Winter G. , Seel F. , Klos K.-P.
Published: March 2015

The missing link in the series of ultramarine pigments, a synthetic sodalite containing yellow S2
- ions, was prepared by thermal decomposition of a thiocyanate sodalite under vacuum or nitrogen. The nature of the product has been elucidated through X-ray powder analysis, VIS/UV-and ESR-spectrometric measurements, and by the observation of the brilliant red fluorescence of the sulfur radical ion S2
-.
(tert-C4H9)3 PTe — ein typisches Tellurophosphoran? [1] / (ferr-C4H9)3 PTe -a Typical Tellurophosphorane? [1]
Authors: Kuhn Norbert , Schumann Hans , Wolmershäuser Gotthelf
Published: March 2015

The P - Te bond length in (tert-C4H9)3PTe of 2.368 Å corresponds to a bond order near 1.5. The distance may be influenced by the tert-C4H9 groups, but the 125Te NMR shift is well within the common R3PTe range, while 1J(125Te-31P) is about 140 Hz smaller than in other tellurophosphoranes.
Zur Darstellung und Kristallstruktur PbZn(NCS)4 / Synthesis and Crystal Structure of PbZn(NCS)4
Authors: Brodersen K. , Procher H. , Hummel Hans-U.
Published: March 2015

PbZn(NCS)4 is obtained from the binary compounds Pb(SCN)2 and Zn(NCS)2 with traces of water in an ultra-sound bath. The space group of the complex is Pn21a (standard: Pna21) with Z = 4. The structure consists of cis-connected octahedra 2
∞[PbS2S4/2] forming two-dimensional layers. All SCN-groups are bound to Zn2+ via their N atoms. The resulting ZnN4 tetrahedra are arranged in the cavities formed by the PbS6 octahedra.
Photolyse von elementarem Schwefel (S6 , S7 , S8 , S10 , S12 ) in Kohlenstoffdisulfidlösung [1] / Photolysis of Elemental Sulfur (S6, S7, S8, S10, S12) in Carbondisulfide Solution [1]
Authors: Strauss Eva-Maria , Steudel Ralf
Published: March 2015

The photochemical decomposition of pure carbondisulfide as well as of solutions of pure S6 , S7 , S8 , S10 and S12 , respectively, in CS2 at 15 °C on irradiation by a high-pressure mercury lamp (200-600 nm) has been studied by quantitative HPLC analysis of the soluble products. In all cases mixtures of sulfur homocycles Sn (n = 5,6, ...) are formed with S8 , S7 and S6 being the dominating species, but traces of S5 , S9 , S10 and S12 have also been observed in most cases. S5 has been identified for the first time; it is formed in particular in the photolysis of S7 in CS2 . All irradiated sulfur solutions reach more or less the same photostationary equilibrium, but the decomposition of CS2 increases linearly with time and its effects are superimposed on the Sn interconversion reactions.
34S-Isotopenaustausch zwischen flüssigem Kohlenstoffdisulfid und elementarem Schwefel [1] / Sulfur-34 Isotopic Exchange between Liquid Carbondisulfide and Elemental Sulfur [1]
Authors: Steudel Ralf , Holz Birger
Published: March 2015

The exchange of sulfur isotopes between liquid carbondisulfide and dissolved elemental sulfur-34 (S6 , S7 , S8 , S9 , S10 , S12) was studied by Raman spectroscopy. No exchange was observed within 4 h at temperatures below 200 °C. Prolonged heating to 200 °C results in a slow exchange (half-life >300 h) as observed by the intensity increase of the symmetric stretching vibration of C32S34 S measured at -120 °C.
Zur Synthese von Tetra-p-tolyldibismutan und dessen Spaltung mit Diphenyldichalkogeniden, elementarem Schwefel, Selen und p-Benzochinon / Synthesis of Tetra-p-tolyldibismuthane and its Cleavage with Diphenyl Dichalcogenides, Elemental Sulfur, Selenium and p-Benzoquinone
Authors: Wieber Markus , Sauer Ingbert
Published: March 2015

(p-CH3C6H4)4Bi2 is obtained from ditolylbismuth bromide with sodium in liquid ammonia. The compound reacts with selenium, sulfur or p-benzoquinone with increasing rate to the corresponding (R2Bi)2E-derivatives (E = S, Se, 1,4-C6H4O2). Reactions of the dibismuthane with equimolar amounts of diphenyl dichalcogenides produce phenylchalcogenobismuthanes of the general formula (p-CH3C6H4)2BiEC6H5 (E - S, Se, Te).
Bis(acetylen)komplexe des Niobs und Tantals / Bis-acetylene Complexes of Niobium and Tantalum
Authors: Alt H. G. , Engelhardt H. E.
Published: March 2015

The photo-induced reaction of C5Me5M(CO)4 complexes (M = Nb, Ta) with excess alkynes R1C2R2(R1, R2 = H, Me, Ph, Hex) in pentane solution results in the formation of the bis-acetylene complexes C5Me5M(R1C2R2)2 CO. In these complexes the π-bonded acetylene ligands behave formally as three electron ligands.
Metallkomplexe funktioneller Isocyanide, XIV [1] [3+2]-Cycloadditionen zwischen Metallo-Nitrilyliden und CS 2 und Carbenübertragung: Thiazolin-2-yliden-Komplexe von Chrom, Wolfram und Palladium / Metal Complexes of Functional Isocyanides, XIV [1] [3+2] Cycloadditions between Metallo Nitrile Ylids and CS 2 and Carbene Transfer: Thiazoline-2-ylidene Complexes of Chromium, Tungsten and Palladium
Authors: Fehlhammer Wolf Peter , Achatz Dagobert , Plaia Ulrike , Völkl Alfons
Published: March 2015

Metal-coordinated α-deprotonated ethyl isocyanoacetate reacts with carbon disulfide in a [3+2]- cycloaddition to give 1.3-thiazolin-2-ylidene complexes, the exo-sulfur function of which has been methylated and coordinated to platinum. The structure of

(3) has been determined by X-ray methods. Inter alia, a surprising shortage of electron derealization in the heterocycle and strong hydrogen bonding between pairs of molecules through their NH- and CO-ester groups have been found. On reacting 3 with PdCl2(η-cyclooctadiene-1,5), carbene transfer occurs to give

.
Synthesis of Apocholic Acid Derivatives by Photochemical Rearrangement of 12-Oxo-steroids
Authors: Hammann Peter E. , Habermehl Gerhard G.
Published: March 2015

The photochemical rearrangement of 3α,24-Diacetoxy-5β,14α-cholan-12-one is described.
Advanced Evaluation of Structural Sealant Glazing Systems by a New System Test Approach
Authors: Kaatz Rico , Recknagel Christoph
Published: March 2015

More information about the capability and especially about the durability of structural sealant glazing (SSG) systems are needed. To make a contribution to unanswered questions, a suitable system evaluation test is necessary. The basis for such a test is a load function, which accounts for the decisive loads SSG systems are exposed to during their working life. This paper proposes a general load function for standard SSG systems at central German locations for accelerated durability tests. Decisive loads are determined and different SSG construction types defined. The performance of these SSG systems under exposure to external loads and to a dynamic pendulum impact is investigated via finite element analyses using a hyperelastic material model. The external loads are applied separately and superimposed. Compression, tensile, and shear deformations of the sealant are determined. It is found that the sealant is subjected to normal and shear stresses simultaneously. The requirements for a representative specimen are derived. The results will be taken as basics for the development and the construction of a test facility to evaluate the durability of structural sealant glazing systems.
Endogenous Gradients of Resting Potential Instructively Pattern Embryonic Neural Tissue via Notch Signaling and Regulation of Proliferation
Authors: Pai Vaibhav P. , Lemire Joan M. , Paré Jean-François , Lin Gufa , Chen Ying , Levin Michael
Published: March 2015

Biophysical forces play important roles throughout embryogenesis, but the roles of spatial differences in cellular resting potentials during large-scale brain morphogenesis remain unknown. Here, we implicate endogenous bioelectricity as an instructive factor during brain patterning inXenopus laevis. Early frog embryos exhibit a characteristic hyperpolarization of cells lining the neural tube; disruption of this spatial gradient of the transmembrane potential (Vmem) diminishes or eliminates the expression of early brain markers, and causes anatomical mispatterning of the brain, including absent or malformed regions. This effect is mediated by voltage-gated calcium signaling and gap-junctional communication. In addition to cell-autonomous effects, we show that hyperpolarization of transmembrane potential (Vmem) in ventral cells outside the brain induces upregulation of neural cell proliferation at long range. Misexpression of the constitutively active form ofNotch, a suppressor of neural induction, impairs the normal hyperpolarization pattern and neural patterning; forced hyperpolarization by misexpression of specific ion channels rescues brain defects induced by activated Notch signaling. Strikingly, hyperpolarizing posterior or ventral cells induces the production of ectopic neural tissue considerably outside the neural field. The hyperpolarization signal also synergizes with canonical reprogramming factors (POUandHB4), directing undifferentiated cells toward neural fatein vivo. These data identify a new functional role for bioelectric signaling in brain patterning, reveal interactions betweenVmemand key biochemical pathways (Notch and Ca2+signaling) as the molecular mechanism by which spatial differences ofVmemregulate organogenesis of the vertebrate brain, and suggest voltage modulation as a tractable strategy for intervention in certain classes of birth defects.
Immune Quiescence of the Brain Is Set by Astroglial Connexin 43
Authors: Boulay Anne-Cécile , Mazeraud Aurélien , Cisternino Salvatore , Saubaméa Bruno , Mailly Phillipe , Jourdren Laurent , Blugeon Corinne , Mignon Virginie , Smirnova Maria , Cavallo Alessia , Ezan Pascal , Avé Patrick , Dingli Florent , Loew Damarys , Vieira Paulo , Chrétien Fabrice , Cohen-Salmon Martine
Published: March 2015

In the normal brain, immune cell trafficking and immune responses are strictly controlled and limited. This unique homeostatic equilibrium, also called brain immune quiescence, is crucial to maintaining proper brain functions and is altered in various pathological processes, from chronic immunopathological disorders to cognitive and psychiatric impairments. To date, the precise nature of factors regulating the brain/immune system interrelationship is poorly understood. In the present study, we demonstrate that one of these regulating factors is Connexin 43 (Cx43), a gap junction protein highly expressed by astrocytes at the blood–brain barrier (BBB) interface. We show that, by setting the activated state of cerebral endothelium, astroglial Cx43 controls immune recruitment as well as antigen presentation mechanisms in the mouse brain. Consequently, in the absence of astroglial Cx43, recruited immune cells elaborate a specific humoral autoimmune response against the von Willebrand factor A domain-containing protein 5a, an extracellular matrix protein of the brain. Altogether, our results demonstrate that Cx43 is a new astroglial factor promoting the immune quiescence of the brain.
Excitation of Tuberoinfundibular Dopamine Neurons by Oxytocin: Crosstalk in the Control of Lactation
Authors: Briffaud Virginie , Williams Paul , Courty Justine , Broberger Christian
Published: March 2015

Milk production in the nursing mother is induced by the hormone prolactin. Its release from the anterior pituitary is generally under tonic inhibition by neuroendocrine tuberoinfundibular dopamine (TIDA) neurons of the arcuate nucleus. Successful nursing, however, requires not only production but also ejection of breast milk. This function is supported by the hormone oxytocin. Here we explored the possibility that interaction between these functionally complementary hormones is mediated by TIDA neurons. First, whole-cell patch-clamp recordings were performed on prepubertal male rat hypothalamic slices, where TIDA neurons can be identified by a robust and rhythmic membrane potential oscillation. Oxytocin induced a switch of this rhythmic activity to tonic discharge through a depolarization involving direct actions on TIDA neurons. The depolarization is sensitive to blockade of the oxytocin receptor and is mediated by a voltage-dependent inward current. This inward current has two components: a canonical transient receptor potential-like conductance in the low-voltage range, and in the high-voltage range, a Ca2+-dependent component. Finally, whole-cell and loose-patch recordings were also performed on slices from virgin and lactating female rats to evaluate the relevance of these findings for nursing. In these preparations, oxytocin was found to excite TIDA neurons, identified by their expression of tyrosine hydroxylase. These findings suggest that oxytocin can modulate prolactin secretion by exciting TIDA neurons, and that this may serve as a feedforward inhibition of prolactin release.
Neural Substrates Underlying the Passive Observation and Active Control of Translational Egomotion
Authors: Huang Ruey-Song , Chen Ching-fu , Sereno Martin I.
Published: March 2015

Moving or static obstacles often get in the way while walking in daily life. Avoiding obstacles involves both perceptual processing of motion information and controlling appropriate defensive movements. Several higher-level motion areas, including the ventral intraparietal area (VIP), medial superior temporal area, parieto-insular vestibular cortex (PIVC), areas V6 and V6A, and cingulate sulcus visual area, have been identified in humans by passive viewing of optic flow patterns that simulate egomotion and object motion. However, the roles of these areas in the active control of egomotion in the real world remain unclear. Here, we used functional magnetic resonance imaging (fMRI) to map the neural substrates underlying the passive observation and active control of translational egomotion in humans. A wide-field virtual reality environment simulated a daily scenario where doors randomly swing outward while walking in a hallway. The stimuli of door-dodging events were essentially the same in two event-related fMRI experiments, which compared passive and active dodges in response to swinging doors. Passive dodges were controlled by a computer program, while active dodges were controlled by the subject. Passive dodges activated several higher-level areas distributed across three dorsal motion streams in the temporal, parietal, and cingulate cortex. Active dodges most strongly activated the temporal–vestibular stream, with peak activation located in the right PIVC. Other higher-level motion areas including VIP showed weaker to no activation in active dodges. These results suggest that PIVC plays an active role in sensing and guiding translational egomotion that moves an observer aside from impending obstacles.
Cortical Efferents Lacking Mutant huntingtin Improve Striatal Neuronal Activity and Behavior in a Conditional Mouse Model of Huntington's Disease
Authors: Estrada-Sánchez Ana María , Burroughs Courtney L. , Cavaliere Stephen , Barton Scott J. , Chen Shirley , Yang X. William , Rebec George V.
Published: March 2015

Abnormal electrophysiological activity in the striatum, which receives dense innervation from the cerebral cortex, is believed to set the stage for the behavioral phenotype observed in Huntington's disease (HD), a neurodegenerative condition caused by mutation of the huntingtin (mhtt) protein. However, cortical involvement is far from clear. To determine whether abnormal striatal processing can be explained by mhtt alone (cell-autonomous model) or by mhtt in the corticostriatal projection cell–cell interaction model, we used BACHD/Emx1–Cre (BE) mice, a conditional HD model in which full-length mhtt is genetically reduced in cortical output neurons, including those that project to the striatum. Animals were assessed beginning at 20 weeks of age for at least the next 40 weeks, a range over which presymptomatic BACHD mice become symptomatic. Both open-field and nest-building behavior deteriorated progressively in BACHD mice relative to both BE and wild-type (WT) mice. Neuronal activity patterns in the dorsal striatum, which receives input from the primary motor cortex (M1), followed a similar age progression because BACHD activity changed more rapidly than either BE or WT mice. However, in the M1, BE neuronal activity differed significantly from both WT and BACHD. Although abnormal cortical activity in BE mice likely reflects input from mhtt-expressing afferents, including cortical interneurons, improvements in BE striatal activity and behavior suggest a critical role for mhtt in cortical output neurons in shaping the onset and progression of striatal dysfunction.
BDNF Interacts with Endocannabinoids to Regulate Cocaine-Induced Synaptic Plasticity in Mouse Midbrain Dopamine Neurons
Authors: Zhong Peng , Liu Yong , Hu Ying , Wang Tong , Zhao Yong-ping , Liu Qing-song
Published: March 2015

Brain-derived neurotrophic factor (BDNF) and endocannabinoids (eCBs) have been individually implicated in behavioral effects of cocaine. The present study examined how BDNF-eCB interaction regulates cocaine-induced synaptic plasticity in the ventral tegmental area and behavioral effects. We report that BDNF and selective tyrosine kinase receptor B (TrkB) agonist 7,8-dihydroxyflavone (DHF) activated the TrkB receptor to facilitate two forms of eCB-mediated synaptic depression, depolarization-induced suppression of inhibition (DSI), and long-term depression (I-LTD) of IPSCs in ventral tegmental area dopamine neurons in mouse midbrain slices. The facilitation appears to be mediated by an increase in eCB production via phospholipase Cγ pathway, but not by an increase in CB1receptor responsiveness or a decrease in eCB hydrolysis. Using Cre-loxP technology to specifically delete BDNF in dopamine neurons, we showed that eCB-mediated I-LTD, cocaine-induced reduction of GABAergic inhibition, and potentiation of glutamatergic excitation remained intact in wild-type control mice, but were impaired in BDNF conditional knock-out mice. We also showed that cocaine-induced conditioned place preference was attenuated in BDNF conditional knock-out mice,in vivopretreatments with DHF before place conditioning restored cocaine conditioned place preference in these mice, and the behavioral effect of DHF was blocked by a CB1receptor antagonist. Together, these results suggest that BDNF in dopamine neurons regulates eCB responses, cocaine-induced synaptic plasticity, and associative learning.
Auditory Properties in the Parabelt Regions of the Superior Temporal Gyrus in the Awake Macaque Monkey: An Initial Survey
Authors: Kajikawa Yoshinao , Frey Stephen , Ross Deborah , Falchier Arnaud , Hackett Troy A. , Schroeder Charles E.
Published: March 2015

The superior temporal gyrus (STG) is on the inferior–lateral brain surface near the external ear. In macaques, 2/3 of the STG is occupied by an auditory cortical region, the “parabelt,” which is part of a network of inferior temporal areas subserving communication and social cognition as well as object recognition and other functions. However, due to its location beneath the squamous temporal bone and temporalis muscle, the STG, like other inferior temporal regions, has been a challenging target for physiological studies in awake-behaving macaques. We designed a new procedure for implanting recording chambers to provide direct access to the STG, allowing us to evaluate neuronal properties and their topography across the full extent of the STG in awake-behaving macaques. Initial surveys of the STG have yielded several new findings. Unexpectedly, STG sites in monkeys that were listening passively responded to tones with magnitudes comparable to those of responses to 1/3 octave band-pass noise. Mapping results showed longer response latencies in more rostral sites and possible tonotopic patterns parallel to core and belt areas, suggesting the reversal of gradients between caudal and rostral parabelt areas. These results will help further exploration of parabelt areas.
Neural Coding of Sound Envelope in Reverberant Environments
Authors: Slama Michaël C.C. , Delgutte Bertrand
Published: March 2015

Speech reception depends critically on temporal modulations in the amplitude envelope of the speech signal. Reverberation encountered in everyday environments can substantially attenuate these modulations. To assess the effect of reverberation on the neural coding of amplitude envelope, we recorded from single units in the inferior colliculus (IC) of unanesthetized rabbit using sinusoidally amplitude modulated (AM) broadband noise stimuli presented in simulated anechoic and reverberant environments. Although reverberation degraded both rate and temporal coding of AM in IC neurons, in most neurons, the degradation in temporal coding was smaller than the AM attenuation in the stimulus. This compensation could largely be accounted for by the compressive shape of the modulation input–output function (MIOF), which describes the nonlinear transformation of modulation depth from acoustic stimuli into neural responses. Additionally, in a subset of neurons, the temporal coding of AM was better for reverberant stimuli than for anechoic stimuli having the same modulation depth at the ear. Using hybrid anechoic stimuli that selectively possess certain properties of reverberant sounds, we show that this reverberant advantage is not caused by envelope distortion, static interaural decorrelation, or spectral coloration. Overall, our results suggest that the auditory system may possess dual mechanisms that make the coding of amplitude envelope relatively robust in reverberation: one general mechanism operating for all stimuli with small modulation depths, and another mechanism dependent on very specific properties of reverberant stimuli, possibly the periodic fluctuations in interaural correlation at the modulation frequency.
Complement Protein C1q Modulates Neurite OutgrowthIn Vitroand Spinal Cord Axon RegenerationIn Vivo
Authors: Peterson Sheri L. , Nguyen Hal X. , Mendez Oscar A. , Anderson Aileen J.
Published: March 2015

Traumatic injury to CNS fiber tracts is accompanied by failure of severed axons to regenerate and results in lifelong functional deficits. The inflammatory response to CNS trauma is mediated by a diverse set of cells and proteins with varied, overlapping, and opposing effects on histological and behavioral recovery. Importantly, the contribution of individual inflammatory complement proteins to spinal cord injury (SCI) pathology is not well understood. Although the presence of complement components increases after SCI in association with axons and myelin, it is unknown whether complement proteins affect axon growth or regeneration. We report a novel role for complement C1q in neurite outgrowthin vitroand axon regrowth after SCI. In culture, C1q increased neurite length on myelin. Protein and molecular assays revealed that C1q interacts directly with myelin associated glycoprotein (MAG) in myelin, resulting in reduced activation of growth inhibitory signaling in neurons. In agreement with a C1q-outgrowth-enhancing mechanism in which C1q binding to MAG reduces MAG signaling to neurons, complement C1q blocked both the growth inhibitory and repulsive turning effects of MAGin vitro. Furthermore, C1q KO mice demonstrated increased sensory axon turning within the spinal cord lesion after SCI with peripheral conditioning injury, consistent with C1q-mediated neutralization of MAG. Finally, we present data that extend the role for C1q in axon growth and guidance to include the sprouting patterns of descending corticospinal tract axons into spinal gray matter after dorsal column transection SCI.