574 research outputs found
LHC main dipoles proposed baseline current ramping
Several studies performed from 1994 to 1996 including some in the framework of the Dynamic Effects Working Group, have shown that the magnitude of the magnetic field imperfections generated in the LHC main dipoles depends partly on the shape of the magnetic field ramp. A current ramp optimisation has been carried out with several combinations of mathematical functions. The result of this study is t he proposed baseline current ramp. The graphic representation of this ramp is included in this report. Theoretical dynamic errors expected with this ramp are compared with those produced with a straig ht ramp at constant current rate, thus demonstrating the improvement obtained. A set of formulae and parameters required for the actual calculation of the baseline ramp is given in the Appendix
Prion expression is activated by Adenovirus 5 infection and affects the adenoviral cycle in human cells
The prion protein is a cell surface glycoprotein whose physiological role remains elusive, while its implication
in transmissible spongiform encephalopathies (TSEs) has been demonstrated. Multiple interactions between
the prion protein and viruses have been described: viruses can act as co-factors in TSEs and life cycles of
different viruses have been found to be controlled by prion modulation.
We present data showing that human Adenovirus 5 induces prion expression. Inactivated Adenovirus did
not alter prion transcription, while variants encoding for early products did, suggesting that the prion is
stimulated by an early adenoviral function. Down-regulation of the prion through RNA interference showed
that the prion controls adenovirus replication and expression.
These data suggest that the prion protein could play a role in the defense strategy mounted by the host
during viral infection, in a cell autonomous manner. These results have implications for the study of the prion
protein and of associated TSEs
Organisation der Notfallstation: Umfeld und Leistungsauftrag bestimmen das Organisationskonzept
Zusammenfassung: Untersuchungsziel: Organisationsformen von Notfallstationen wurden analysiert, um Gestaltungsgrundsätze abzuleiten. Methoden: Organisation und Leistungsauftrag der klinischen Notfallmedizin wurden anhand einer Literaturrecherche verglichen. Dabei wurden organisatorische Grundmuster in Abhängigkeit von der Anwesenheit von Spezialisten (Spezialisierung) und der Einbindung in die Spitalorganisation (Integration) entwickelt und aufgrund etablierter Effizienzkriterien vergleichend bewertet. Ergebnisse: Klinische Notfallstationen unterscheiden sich hinsichtlich Autonomiegrad, Leistungsbreite und Leistungstiefe. Vier Archetypen wurden abgegrenzt: Das Profit-Center als ertragsorientierte Wirtschaftseinheit, das Service-Center als auftragserfüllende Organisationseinheit, die funktionelle Organisation als fachlich abgegrenzte Einheit und die modulare Organisation, die sich durch eine zentrale Notfalleinheit und rasch mobilisierbare Spezialistenteams auszeichnet. Schlussfolgerungen: Es gibt keinen Königsweg. Jede organisatorische Lösung bietet in Abhängigkeit von Umfeldbedingungen und Leistungsauftrag Vor- und Nachteile. Die organisatorischen Grundmuster bieten eine Orientierungshilfe, wobei Leistungsvolumen und -spektrum wichtige Determinanten darstelle
Tetramethylammonium dihydrogen phosphate hemihydrate
In the crystal structure of the title compound, C4H12N+·H2PO4
−·0.5H2O, the anions form an infinite hydrogen-bonded chain along the [10] direction. The anion chains are connected by water molecules, which lie on crystallographic twofold rotation axes, through O—H⋯O hydrogen bonds. These hydrogen bonds are almost perpendicular to the other hydrogen bonds which create an assembled structure of anions. In addition, C—H⋯O hydrogen bonds between anions and cations are observed
5-Methoxy-2,2-dimethyl-6-[(2E)-2-methylbut-2-enoyl]-10-phenyl-2H,8H-pyrano[2,3-f]chromen-8-one (calophyllolide)
The title compound, C26H24O5, was isolated from calophyllum inophyllum seeds. In the molecule, the phenyl and 2-methylbut-2-enoyl groups are almost orthogonal to the chromene fragment [C—C—C—C torsion angles = 81.4 (3) and −90.1 (2)°, respectively]. In the crystal packing, centrosymmetrically related molecules are linked by C—H⋯O contacts into dimers, which are connected via further C—H⋯O interactions into a double chain along [010]
Interplay of the nuclear envelope with chromatin in physiology and pathology
The nuclear envelope compartmentalizes chromatin in eukaryotic cells. The main nuclear envelope components are lamins that associate with a panoply of factors, including the LEM domain
proteins. The nuclear envelope of mammalian cells opens up during cell division. It is reassembled
and associated with chromatin at the end of mitosis when telomeres tether to the nuclear
periphery. Lamins, LEM domain proteins, and DNA binding factors, as BAF, contribute to the
reorganization of chromatin. In this context, an emerging role is that of the ESCRT complex, a
machinery operating in multiple membrane assembly pathways, including nuclear envelope
reformation. Research in this area is unraveling how, mechanistically, ESCRTs link to nuclear
envelope associated factors as LEM domain proteins. Importantly, ESCRTs work also during
interphase for repairing nuclear envelope ruptures. Altogether the advances in this field are
giving new clues for the interpretation of diseases implicating nuclear envelope fragility, as
laminopathies and cancer
Choline dihydrogen phosphate
In the cystal structure of the title compound, (2-hydroxyethyl)trimethylammonium dihydrogen phosphate, C5H14NO+·H2PO4
−, two anions create dimeric structures via two O—H⋯O hydrogen bonds. The hydrogen-bonded dimers are connected by another O—H⋯O hydrogen bond with the hydroxyl groups of the cations, constructing a columner structure along the a axis. A number of C—H⋯O interactions are also present
The cobalt(II) salt of the azo dye Orange G
Crystallizing the cobalt(II) salt of the azo dye Orange G from water was found to give the solvent-separated ion-pair species hexaaquacobalt(II) 7-oxo-8-(2-phenylhydrazin-1-ylidene)-7,8-dihydronaphthalene-1,3-disulfonate tetrahydrate, [Co(H2O)6](C16H10N2O7S2)·4H2O. The asymmetric unit of the cobalt(II) salt contains three independent octahedral [Co(OH2)6]2+ cations, three azo anions, all with similar configurations, and 12 uncoordinated water molecules. The structure is closely related to that of one of the known magnesium analogues. Both structures have Z′ = 3, feature nearly planar azo anions [maximum displacement of azo-N atoms from the plane of the phenyl ring = 0.058 (7) Å] in their hydrazone tautomeric form, form layer structures with hydrophilic and hydrophobic layers alternating along the b-axis direction, and are stabilized by an extensive network of hydrogen bonds.
4,5-Dimethyl-1,2-diphenyl-1H-imidazole monohydrate
In the title compound, C17H16N2·H2O, the imidazole ring is essentially planar [maximum deviation = 0.0037 (7) Å]. The imidazole ring makes dihedral angles of 80.74 (7) and 41.62 (7)° with the phenyl rings attached to the N and C atoms, respectively. The dihedral angle between the two phenyl rings is 75.83 (8)°. Intermolecular O—H⋯N and O—H⋯O hydrogen bonds are found in the crystal structure
Ethyl 4-(4-bromophenyl)-6-r-phenyl-2-oxocyclohex-3-ene-1-t-carboxylate
In the title compound, C21H19BrO3, the cyclohexene ring adopts an envelope conformation, with all substituents equatorial. The plane through its five coplanar atoms makes dihedral angles of 28.88 (10) and 71.94 (10)° with the bromobenzene and phenyl rings, respectively. The dihedral angle between the latter two rings is 51.49 (15)°. Intermolecular C—H⋯O hydrogen bonds are found in the crystal structure; a C—H⋯π interaction is also present
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