Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 11
    Electronic Resource
    Electronic Resource
    Ion association and condensation in primitive models of electrolyte solutions (1999)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 111 (1999), S. 9000-9008 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Monte Carlo simulations have been used to investigate condensation and ion association in primitive models of electrolyte solutions. We have examined models in which the ions have equal diameter, the cation charge is +Zq, and the anion charge is −q, with Z=1, Z=2, and Z=4. Z=1 corresponds to the familiar restricted primitive model. Rough estimates of the critical temperatures have been obtained. In all cases the vapor phase is highly associated, with the ions forming electroneutral pairs, triples, and quintuples for Z=1, Z=2, and Z=4, respectively. Ion association has been investigated using a nearest-neighbor distribution function. For each value of Z the onset of ion dissociation in the low-density vapor is shown to occur at a temperature very close to the critical temperature. This raises the possibility of ion association affecting the critical behavior of ionic fluids. We have compared the simulation results for the restricted primitive model with the predictions of Debye–Hückel-based theories and the pairing mean spherical approximation. All of the theories perform well in the vapor phase, but are less successful in the liquid phase. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.480243
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Geminate recombination and vibrational relaxation dynamics of aqueous chlorine dioxide: A time-resolved resonance Raman study (1998)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 109 (1998), S. 2596-2599 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The photochemical dynamics of aqueous chlorine dioxide (OClO) are investigated using time-resolved resonance Raman spectroscopy. Stokes and anti-Stokes spectra are measured as a function of time following photoexcitation of OClO using degenerate pump and probe wavelengths at 390 nm. The temporal evolution of OClO Stokes intensity is found to be consistent with the reformation of ground-state OClO by subpicosecond geminate recombination of the primary ClO and O photofragments. Anti-Stokes intensity is observed for transitions corresponding to the symmetric stretch of OClO demonstrating that upon geminate recombination, excess vibrational energy is deposited along this coordinate. Dissipation of this energy to the surrounding solvent occurs with a time constant of ∼9 ps. Finally, a delay in the appearance of OClO anti-Stokes intensity relative to geminate recombination is observed demonstrating that the excess vibrational energy available to OClO is initially deposited along the resonance Raman inactive asymmetric stretch coordinate with the exchange of energy between this coordinate and the symmetric stretch occurring with a time-constant of ∼5 ps. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.476873
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Demixing in hard ellipsoid rod-plate mixtures (1997)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 106 (1997), S. 9270-9275 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The phase behavior of fluid mixtures of hard uniaxial ellipsoids with elongations e and 1/e, and equal molecular volume, has been studied using constant-pressure Gibbs ensemble Monte Carlo simulations for e=15 and e=20. Four distinct phases are observed: isotropic (I), uniaxial nematic (N+ and N−) and biaxial nematic (B). The region of stability of the biaxial phase is found to be limited severely by demixing into two coexisting uniaxial phases. This is in agreement with recent theoretical predictions. The theory, however, does not account for the surprising asymmetry of the phase diagram that we find in our simulations. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.474012
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Phase diagram of the hard biaxial ellipsoid fluid (1997)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 106 (1997), S. 6681-6688 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The phase diagram of fluids of hard biaxial ellipsoids with c/a=10 and b/a∈{1,10}, where a, b, and c are the semi-axes, has been studied using computer simulation. Four homogeneous phases are in evidence: isotropic (I), nematic (N+), discotic (N−) and biaxial (B). First-order isotropic-nematic and isotropic-discotic coexistence lines have been traced out using Gibbs–Duhem integration of the coexistence pressure with respect to the molecular biaxiality. We conclude that the isotropic-nematic transition is greatly weakened by a modest degree of molecular biaxiality, in agreement with several recent theories. The I–N+ and I–N− lines meet two second-order nematic-biaxial and discotic-biaxial lines at the Landau bicritical point. This point is predicted to occur at around the self-dual particle shape, b/a=c/a, and so extensive simulations have been performed at and around this point. Very sluggish behaviour is expected in this region of the phase diagram and so long simulations were required. An estimate of the location of the Landau bicritical point is reported. We also highlight the asymmetry of the phase diagram about b/a=c/a, where the ellipsoid is neither prolate nor oblate. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.473665
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    FOREWARD (1993)
    Oxford, UK : Blackwell Publishing Ltd
    BJOG 100 (1993), S. 0 
    Details
    ISSN: 1471-0528
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-0528.1993.tb10624.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    The use of the fetal electrocardiogram in labour (1994)
    Oxford, UK : Blackwell Publishing Ltd
    BJOG 101 (1994), S. 0 
    Details
    ISSN: 1471-0528
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-0528.1994.tb13003.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    The use of fax machines improves out of hours labour ward management (1993)
    Oxford, UK : Blackwell Publishing Ltd
    BJOG 100 (1993), S. 0 
    Details
    ISSN: 1471-0528
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-0528.1993.tb15152.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Detergents and Peptides Alter Proteolysis and Calmodulin Binding of B-50/GAP-43 In Vitro (1994)
    Oxford, UK : Blackwell Science Ltd
    Journal of neurochemistry 63 (1994), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: The neuronal growth-associated protein B-50/GAP-43 is a substrate for protein kinase C, binds to calmodulin in a calcium-independent manner, and in vitro is subject to an endogenous and chymotrypsin-mediated hydrolysis in the vicinity of the single kinase C phosphorylation site. All of these processes can be influenced by corticotrophin (ACTH). In the present study we have investigated whether these biochemical interactions involving B-50 could have common structural determinants. Chymotryptic digestion of B-50 in the presence or absence of a nonionic detergent and ACTH demonstrated that hydrolysis is potentiated by a lipid-like environment that primarily affects the protein rather than the protease or the peptide. Furthermore, this lipid dependency appears to extend to the binding of dephosphorylated B-50 to calmodulin, which appears to occur only in the presence of a nonionic detergent or lipid and the absence of calcium. A structure-activity study for ACTH-mediated inhibition of B-50 proteolysis by an endogenous protease that copurifies with B-50 in a detergent extract of synaptosomal plasma membranes showed that ACTH1–24, ACTH5–24, ACTH5–16, dynorphin, and corticostatin inhibited the conversion of rat B-50 to B-5041–226. In contrast, ACTH7–16, Org2766, and neurotensin had no detectable effect on B-50 proteolysis at concentrations of 10 and 50 µM. The results indicate that in common with effects in other B-50-containing systems, inhibition of proteolysis is related to the presence of a basic amphiphilic helix in those ACTH fragments and analogues that were inhibitory and, moreover, the presence of this motif in other peptides appears to confer inhibitory activity. The results are discussed with reference to the putative secondary structure of B-50 and changes that may take place in the presence of membrane lipids or nonionic detergents. The conclusions of this study suggest that in vitro B-50 is subject to regulation by posttranslational enzymes and binding proteins as a consequence of its ability to adapt an amphiphilic helix conformation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1471-4159.1994.63041491.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Extracellular Glutamate Is Increased in Thalamus During Thiamine Deficiency-Induced Lesions and Is Blocked by MK-801 (1993)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 61 (1993), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The current study measured extracellular fluid (ECF) levels of excitatory amino acids before and during the onset of thiamine deficiency-induced pathologic lesions. Male Sprague-Dawley rats were treated with daily pyrithiamine (0.25 mg/kg i.p.) and a thiamine-deficient diet (PTD). Microdialysates were simultaneously collected from probes inserted acutely via guide cannulae into right paracentral and ventrolateral nuclei of thalamus and left hippocampus of PTD and pair-fed controls. Hourly samples were collected from unanesthetized and freely moving animals. Basal levels obtained at a prelesion stage (day 12 of PTD treatment) were unchanged from levels in pairfed controls. In samples collected 4–5 h after onset of seizures (day 14 of PTD), the levels of glutamate were elevated an average 640% of basal levels in medial thalamus and 200% in hippocampus. Glutamine levels declined, taurine and glycine were elevated, and aspartate, GABA, and alanine were unchanged during this period. Within 7 h after seizure onset glutamine was undetectable in both areas, whereas glutamate had declined to ∼200% in thalamus and 70% in hippocampus. No significant change in glutamate, aspartate, or other amino acids was observed in dialysates collected from probes located in undamaged dorsal-lateral regions of thalamus. Number of neurons within ventrolateral nucleus of thalamus was significantly greater in PTD animals in which the probe was dialyzed compared with nondialyzed, suggesting that removal of excitatory amino acids was protective. No significant pathologic damage was evident in hippocampus. Pretreatment with MK-801 completely blocked the rise of ECF glutamate and significantly reduced the pathologic damage within thalamus of PTD rats and produced a significant decrease in ECF glutamate in control rats.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1993.tb07457.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    ADP-Ribosylation of the Neuronal Phosphoprotein B-50/GAP-43 (1993)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 60 (1993), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: The neuronal phosphoprotein B-50/GAP-43 is associated with growth and regeneration within the nervous system and its posttranslational status can be correlated with its cellular localization during growth and regeneration. Recently, B-50 has been shown to interact with certain G protein subunits. Regulation of G protein-mediated signal transduction may involve ADP-ribosylation in vivo. In the present study we have demonstrated that B-50 is a substrate for endogenous ADP-ribosyltransferases. The results are discussed with respect to the possible interaction of B-50 with G proteins, but also with regard to the posttranslational modification of B-50 by all major regulatory mechanisms that act at, or through, the neuronal membrane.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1993.tb05862.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...