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1Latest Papers from Table of Contents or Articles in PressD. S. Adler ; K. N. Wilkinson ; S. Blockley ; D. F. Mark ; R. Pinhasi ; B. A. Schmidt-Magee ; S. Nahapetyan ; C. Mallol ; F. Berna ; P. J. Glauberman ; Y. Raczynski-Henk ; N. Wales ; E. Frahm ; O. Joris ; A. MacLeod ; V. C. Smith ; V. L. Cullen ; B. Gasparian
American Association for the Advancement of Science (AAAS)
Published 2014Staff ViewPublication Date: 2014-09-27Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Animals ; Armenia ; *Biological Evolution ; History, Ancient ; Hominidae/*anatomy & histology ; Humans ; Technology/*historyPublished by: -
2Latest Papers from Table of Contents or Articles in PressStaff View
Publication Date: 2018-05-11Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyGeosciencesComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Epidemiology, GeneticsPublished by: -
3Latest Papers from Table of Contents or Articles in PressKistler, L., Maezumi, S. Y., Gregorio de Souza, J., Przelomska, N. A. S., Malaquias Costa, F., Smith, O., Loiselle, H., Ramos-Madrigal, J., Wales, N., Ribeiro, E. R., Morrison, R. R., Grimaldo, C., Prous, A. P., Arriaza, B., Gilbert, M. T. P., de Oliveira Freitas, F., Allaby, R. G.
American Association for the Advancement of Science (AAAS)
Published 2018Staff ViewPublication Date: 2018-12-14Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyGeosciencesComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: AnthropologyPublished by: -
4Articles: DFG German National LicensesWales, N. P. L. ; Buma, W. J. ; de Lange, C. A. ; Lefebvre-Brion, H.
College Park, Md. : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: The intensity anomalies in the spin–orbit and rotational branching ratios in the zero kinetic energy pulsed-field ionization (ZEKE-PFI) spectra via the F 1Δ2, D 1Π1, and f 3Δ2 Rydberg states of HCl have been studied. In general, the branching ratios are observed to depend on three parameters employed in the pulsed field ionization experiment: (i) the delay time between excitation and ionization; (ii) the magnitude of the bias electric field; and (iii) the magnitude of the applied pulsed electric field. The results can be rationalized on the basis of the increasing number of autoionization decay channels that become available to the high-n Rydberg states as each ionization threshold is surpassed. The delay dependence of the ZEKE-PFI spectra via the F 1Δ2 state has been analyzed in more detail by ab initio calculations. These calculations show that the observed spin–orbit branching ratios can be reproduced thereby giving evidence for a nonexponential decay of the high-n Rydberg states (n≈100). © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesWales, N. P. L. ; de Beer, E. ; Westwood, N. P. C. ; Buma, W. J. ; de Lange, C. A. ; van Hemert, M. C.
College Park, Md. : American Institute of Physics (AIP)
Published 1994Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: The ionization and dissociation processes occurring after two-photon excitation of the d 1Σ+ state of NH have been investigated using one- and two-color multiphoton ionization spectroscopy in combination with mass-resolved ion and kinetic energy-resolved electron detection. The photoelectron spectra obtained for ionization of the molecule via the d 1Σ+ state (v'=0,1) reveal a one-photon ionization process to all energetically accessible vibrational levels of the X 2Π ground ionic state, at variance with a one-configuration description of the two states. Moreover, electrons are observed that derive from a one-photon ionization of excited neutral nitrogen and hydrogen atoms. Two-color excitation experiments of the d 1Σ+ state show that the influence of discrete states at the overall three-photon level on the dissociation dynamics is insignificant. Using the results of ab initio calculations it is concluded that these experimental observations can be interpreted consistently if two competing processes are assumed to take place from the d 1Σ+ excited state: a molecular one-photon ionization which is forbidden in zeroth order, and a two-photon nonresonance enhanced excitation to neutral (pre)dissociative states.Type of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesWales, N. P. L. ; Buma, W. J. ; de Lange, C. A. ; Lefebvre-Brion, H. ; Wang, Kwanghsi ; McKoy, V.
College Park, Md. : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: The results of rotationally resolved resonance enhanced multiphoton ionization photoelectron spectroscopy and zero kinetic energy-pulsed field ionization studies on HBr via various rotational levels of the F 1Δ2 and f 3Δ2 Rydberg states are reported. These studies lead to an accurate determination of the lowest ionization threshold as 94 098.9±1 cm−1. Observed rotational and spin–orbit branching ratios are compared to the results of ab initio calculations. The differences between theory and experiment highlight the dominant role of rotational and spin–orbit interactions for the dynamic properties of the high-n Rydberg states involved in the pulsed field ionization process. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesWales, N. P. L. ; Buma, W. J. ; de Lange, C. A. ; Lefebvre-Brion, H.
College Park, Md. : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: Rotationally and parity resolved excitation spectra of autoionizing Rydberg states of HBr in the energy region between the 2Π3/2 and 2Π1/2 ionic thresholds have been obtained in a double resonant excitation scheme via single rotational levels of the vibrationless F 1Δ2 Rydberg state. A cursory examination of these spectra reveals the presence of s, p, d, and f Rydberg series. Apart from the f series, which show almost Hund's case (e) coupling, these series clearly exhibit an angular momentum coupling scheme intermediate between Hund's case (c) and (e). As a result it is difficult to assign them as converging upon specific ionic rotational thresholds. A detailed analysis of the excitation spectra has consequently been performed employing multichannel quantum defect theory calculations, allowing for a determination of the quantum defects of the Hund's case (a) basis states and the relevant transition moments, and, concurrently, the assignment of nearly all the observed autoionizing resonances. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesStaff View
ISSN: 1095-8649Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: BiologyNotes: Pike were adapted to both fresh water and brackish water (salinity 2.2‰) conditions prior to measurements of blood pressure, electrolyte composition and renal function both before and after administration of either 3.75 μg calcitonin kg−1 body weight or acetate saline. This protocol was designed to test the ability of calcitonin to affect significantly the fluid and electrolyte status of fish exposed to varying salinity. Whilst in freshwater-adapted animals the plasma content of calcium and magnesium was significantly depressed following calcitonin injection, no corresponding effect was seen following 2.2‰ salinity brackish water-adaptation. Moreover, no significant changes were apparent in renal function of pike adapted to either medium. It is concluded from these experiments that calcitonin in pike may play some part in extra-renal control of plasma calcium and magnesium content in fresh water but that it is unable to affect significantly the measured plasma ion content of brackish water-adapted animals.Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesStaff View
ISSN: 1432-136XSource: Springer Online Journal Archives 1860-2000Topics: BiologyMedicineNotes: Summary Hagfish,Myxine glutinosa, were used in an investigation of the possible effects of various eicosanoids and the prostaglandin synthetase inhibitor indomethacin, on cortisol production, blood pressure control, urine flow and electrolyte balance. Cortisol levels in plasma of untreated control animals and plasma from animals 1 h following injection of 50 μg kg−1 prostaglandin E1, E2, A2, F2α TXB2 and indomethacin were not detectable. However, plasma cortisol levels rose to between 10 and 26 pg ml−1 1 h following injection of either 50 μg kg−1 arachidonic acid or prostaglandin E2. This rise was similar in magnitude to that produced 1 h following administration of 50 μg kg−1 porcine ACTH. The resting dorsal aortic blood pressure of between 3.50 and 3.75 mmHg was reduced on average by 50% for 12–15 min when animals received 10 μg kg−1 arachidonic acid, prostaglandin E1, E2, A2, and TXB2 and was effectively reduced to zero for 20 min or more following 50 μg kg−1 of these eicosanoids. Similar doses of prostaglandin F2α, however, evoked an increase in blood pressure (19–33%) whilst indomethacin was without effect. Control measurements of urine flow inMyxine were estimated to be between 540 and 660 μl h−1 kg−1. There was a marked reduction in urine output following the arterial vasodepression induced by arachidonic acid, prostaglandin E1, E2, A2 and TXB2 in doses of 10 μg kg−1, an effect which became even more pronouced following injection of 50 μg kg−1 quantities, leading in some cases to complete anuria. There was no significant change in urine volume following either the vasopressor action of prostaglandin F2α or following indomethacin. None of the compounds tested in this study significantly influenced the plasma or urine electrolyte status ofMyxine.Type of Medium: Electronic ResourceURL: