This study describes an integrated workflow designed to quantify detrital input into lacustrine deposits in terms of regional extent and total organic carbon content. includes (a) geochemical data such as Rock Eval palynofacies (b) palaeogeographical maps. was applied the immature Barremian source rocks from Lower Congo Basin because a large available set describing complex sedimentary record. ...

The effect of barium on Müller cell K+ conductance was evaluated in the tiger salamander using enzymatically dissociated cells and cells in situ (retinal slice and isolated retina). Barium effects were similar in both cases. In dissociated cells, 50 microM Ba2+ depolarized cells 14.7 mV and raised cell input resistance from a control value of 16.0 to 133 M omega. For cells in situ, 50 microM Ba...

In zebrafish embryos, the axons of the posterior trigeminal (Vp) and facial (VII) motoneurons project stereotypically to a small number of target muscles derived from the first and second branchial arches (BA1, BA2). Use of the Islet1 (Isl1)-GFP transgenic line enabled precise real-time observations of the growth cone behaviour of the Vp and VII motoneurons within BA1 and BA2. Screening for N-e...

Using various envelope mutants of Escherichia coli, the relationship between cell surface struc­ ture and the Ca2*or Ba2+-dependent competence for transfection was investigated. In contrast with rough strains, smooth bacteria treated with Ca2+ or Ba2+ were incompetent for the trans­ fection by 0 A RF. In E. coli K12 D21 derivatives, Ca2+-dependent competence remarkably in­ creased by IpsA l mut...

Bi1−xBaxFeO3 (0 ≤ x ≤ 0.3) nanopowders were synthesized using sol-gel technique. The structural and magnetic properties were investigated using X-ray diffraction, SEM and VSM. As Ba2+ doping concentration was increased, the structure of the samples changed from rhombohedral to tetragonal or monoclinic. The structural change might be an important factor for achieving the ferroelectric properties...

Using Ba2+ as a probe, we performed a detailed characterization of an external K+ binding site located in the pore of a large conductance Ca2+-activated K+ (BKCa) channel from skeletal muscle incorporated into planar lipid bilayers. Internal Ba2+ blocks BKCa channels and decreasing external K+ using a K+ chelator, (+)-18-Crown-6-tetracarboxylic acid, dramatically reduces the duration of the Ba2...

Using permeabilized gonadotropes, we examined whether Ca2(+)-stimulated luteinizing-hormone (LH) exocytosis is mediated by the Ca2(+)-activated phospholipid-dependent protein kinase (protein kinase C). In the presence of high [Ca2+]free (pCa 5), alpha-toxin-permeabilized sheep gonadotropes secrete a burst of LH and then become refractory to maintained high [Ca2+]free. The protein kinase C activ...

The coupling between Ca2+ extrusion and H+ uptake by the ubiquitous plasma membrane calcium ATPase (PMCA) has not been measured in any neurone. I have investigated this with Ca2+- and pH-sensitive microelectrodes in large voltage-clamped snail neurones, which have no Na+-Ca2+ exchangers. The recovery of [Ca2+]i and surface pH after a brief depolarization or Ca2+ injection was not slowed by hype...

The crystal structure of Ba2YCu3O8-03B4 (03B4=1.74) at 20K and 298K has been determined by single-crystal neutron diffraction. In contrast to the superconducting orthorhombic phase for which 6 ~ 1.1, this phase crystallizes in the tetragonal space group P4/MMM wtih 03B1 = 3.8573(4)Å and c = 11.7913(10)Å. The increase in oxygen vacancies compared to Ba2YCu3O8-03B4 (6 ~1.1.) is confined entirely ...