Ueber die Veresterung der Alkalicellulose I

1) Es wurden untersucht die Einflüsse der Reinheit des Fettsäurechlorides, der überschüssigen Alkalilauge in der Alkalicellulose, der Menge des verwendeten Säurechlorides, der Temperatur bei der Herstellung der Alkalicellulose sowie bei der Veresterung, der Alterung und des Trocknens der Alkalicellulose auf die Veresterung der Alkalicellulose mit Fettsäurechlorid. 2) Bei der Veresterung der Alkalicellulose mit verschiedenen Säurechloriden hängt der Veresterungsgrad von der Art der Säure ab. 3) Durch Veresterung der Alkalicellulose mit höheren Fettsäurechloriden lässt sich auf die in der Alkalicellulose gebundene Alkalimenge schliessen, während der gleiche Zweck mit Benzoesäurechlorid schwer erzielbar ist

Celluloseester der Naphthensäuren

1. Durch Erwärmung von Cellulose mit Naphthensäurechlorid bezw. Anhydrid in Gegenwart von Pyridin wird Ester gebildet. 2. Aus Alkalicellulose mit Naphthensäurechlorid bildet sich Ester. 3. Mit 2-2.5 Mol. Naphthensäure gegen 1 Mol. C₆ H₁₀ O₅ bildet sich ein Ester. 4. Untersucht wurden die Eigenschaften des Celluloseesters, besonders sein Verhalten gegen Wärme und Lösungsmittel

Untersuchungen über die Celluloseester der höheren Fettsäuren : I. Mitteilung : Über die Esterbildung aus ursprünglicher Cellulose und über die Eigenschaften der erzielten Ester

1) Bei Gegenwart von Pyridin werden aus Cellulose und höheren Säureanhydriden Ester gebildet. Deren Fettsäuregehalt ist jedoch niedrig. 2) Im Gegensatz zu Grün und Wittka lassen sich nach den beschriebenen Versuchen benzol- bezw, ätherlösliche Ester erzielen. 3) Nach Gault ist die Esterbildung aus der ursprünglichen Cellulose unmöglich, während unsere Versuche selbst unter gewöhnlichen Druck diese Möglichkeit ergeben. 4) Der Schmelzpunkt ist h5her als der früher angenommene. 5) Der höchste der homologen Ester ist höchst wahrscheinlich Triester

Tunable Multifunctional Topological Insulators in Ternary Heusler Compounds

Recently the Quantum Spin Hall effect (QSH) was theoretically predicted and experimentally realized in a quantum wells based on binary semiconductor HgTe[1-3]. QSH state and topological insulators are the new states of quantum matter interesting both for fundamental condensed matter physics and material science[1-11]. Many of Heusler compounds with C1b structure are ternary semiconductors which are structurally and electronically related to the binary semiconductors. The diversity of Heusler materials opens wide possibilities for tuning the band gap and setting the desired band inversion by choosing compounds with appropriate hybridization strength (by lattice parameter) and the magnitude of spin-orbit coupling (by the atomic charge). Based on the first-principle calculations we demonstrate that around fifty Heusler compounds show the band inversion similar to HgTe. The topological state in these zero-gap semiconductors can be created by applying strain or by designing an appropriate quantum well structure, similar to the case of HgTe. Many of these ternary zero-gap semiconductors (LnAuPb, LnPdBi, LnPtSb and LnPtBi) contain the rare earth element Ln which can realize additional properties ranging from superconductivity (e. g. LaPtBi[12]) to magnetism (e. g. GdPtBi[13]) and heavy-fermion behavior (e. g. YbPtBi[14]). These properties can open new research directions in realizing the quantized anomalous Hall effect and topological superconductors.Comment: 20 pages, 5 figure

The NR4A subgroup: immediate early response genes with pleiotropic physiological roles

The nuclear hormone receptor (NR) superfamily includes the orphan NR4A subgroup, comprised of Nur77 (NR4A1), Nurr1 (NR4A2) and NOR-1 (NR4A3). These NRs are classified as early response genes, are induced by a diverse range of signals, including fatty acids, stress, growth factors, cytokines, peptide hormones, phorbol esters, neurotransmitters, and physical stimuli (for example magnetic fields, shear stress). The ability to sense and rapidly respond to changes in the cellular environment thus appears to be a hallmark of this subfamily. The members of the NR4A subgroup are well conserved in the DNA binding domain (~91-95%) and the C-terminal ligand-binding domain (~60%), but are divergent in the N-terminal AB region. These receptors bind as monomers, homodimers and heterodimers with RXRs (to mediate retinoid signaling) to different permutations of the canonical NR binding motif. The NR4A subgroup activates gene expression in a constitutive ligand-independent manner. NR4A-mediated trans-activation (LBD) involves unusually active N-terminal AF-1 domains that mediate coactivator recruitment. Moreover, the NR4A receptors encode atypical LBDs and AF-2 domains. For example, the LBDs contain no cavity due to bulky hydrophobic residue side chains, and lack the classical coactivator-binding cleft constituted by helices 3, 4 and 12. However, a hydrophobic patch exists between helices 11 and 12, that encodes a novel cofactor interface that modulates transcriptional activity. In line with the pleiotropic physiological stimuli that induce the NR4A subgroup, these orphan NRs have been implicated in cell cycle regulation (and apoptosis), neurological disease, steroidogenesis, inflammation, carcinogenesis and atherogenesis

Inter-rater agreement in the assessment of abnormal chest X-ray findings for tuberculosis between two Asian countries

<p>Abstract</p> <p>Background</p> <p>Inter-rater agreement in the interpretation of chest X-ray (CXR) films is crucial for clinical and epidemiological studies of tuberculosis. We compared the readings of CXR films used for a survey of tuberculosis between raters from two Asian countries.</p> <p>Methods</p> <p>Of the 11,624 people enrolled in a prevalence survey in Hanoi, Viet Nam, in 2003, we studied 258 individuals whose CXR films did not exclude the possibility of active tuberculosis. Follow-up films obtained from accessible individuals in 2006 were also analyzed. Two Japanese and two Vietnamese raters read the CXR films based on a coding system proposed by Den Boon et al. and another system newly developed in this study. Inter-rater agreement was evaluated by kappa statistics. Marginal homogeneity was evaluated by the generalized estimating equation (GEE).</p> <p>Results</p> <p>CXR findings suspected of tuberculosis differed between the four raters. The frequencies of infiltrates and fibrosis/scarring detected on the films significantly differed between the raters from the two countries (<it>P </it>< 0.0001 and <it>P </it>= 0.0082, respectively, by GEE). The definition of findings such as primary cavity, used in the coding systems also affected the degree of agreement.</p> <p>Conclusions</p> <p>CXR findings were inconsistent between the raters with different backgrounds. High inter-rater agreement is a component necessary for an optimal CXR coding system, particularly in international studies. An analysis of reading results and a thorough discussion to achieve a consensus would be necessary to achieve further consistency and high quality of reading.</p