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  • 1
    Electronic Resource
    Electronic Resource
    Interpretation of neovolcanic versus palaeovolcanic sand grains: an example from Miocene deep-marine sandstone of the Topanga Group (Southern California) (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Sedimentology 42 (1995), S. 0 
    Details
    ISSN: 1365-3091
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: Despite abundant data on volcaniclastic sand(stone), the compositional, spatial and temporal distribution of volcanic detritus within the sedimentary record is poorly documented. One of the most intricate tasks in optical analysis of sand(stone) containing volcanic particles is to distinguish grains derived by erosion of ancient volcanic rocks (i.e. palaeovolcanic, noncoeval grains) from grains generated by active volcanism (subaqueous and/or subaerial) during sedimentation (neovolcanic, coeval grains).Deep-marine volcaniclastic sandstones of the Middle Topanga Group of southern California are interstratified with 3000-m-thick volcanic deposits (both subaqueous and subaerial lava and pyroclastic rocks, ranging from basalt, andesite to dacite). These rocks overlie quartzofeldspathic sandstones (petrofacies 1) of the Lower Topanga Group, derived from deep erosion of a Mesozoic magmatic arc.Changes in sandstone composition in the Middle Topanga Group provide an example of the influence of coeval volcanism on deep-marine sedimentation. Volcaniclastic strata were deposited in deep-marine portions of a turbidite complex (volcaniclastic apron) built onto a succession of intrabasinal lava flows and on the steep flanks of subaerially emplaced lava flows and pyroclastic rocks.The Middle Topanga Group sandstones are vertically organized into four distinctive petrofacies (2–5). Directly overlying basalt and basaltic-andesite lava flows, petrofacies 2 is a pure volcanolithic sandstone, including vitric, microlitic and lathwork volcanic grains, and neovolcanic crystals (plagioclase, pyroxene and olivine). The abundance of quenched glass (palagonite) fragments suggests a subaqueous neovolcanic provenance, whereas sandstones including andesite and minor basalt grains suggest subaerial neovolcanic provenance. This petrofacies probably was deposited during syneruptive Periods, testifying to provenance from both intrabasinal and extrabasinal volcanic events. Deposited during intereruptive periods, impure volcanolithic petrofacies 3 includes both neovolcanic (85%) and older detritus derived from plutonic, metamorphic and palaeovolcanic rocks. During post-eruptive periods, the overlying quartzofeldspathic petrofacies 4 and 5 testify to progressive decrease of neovolcanic detritus (48–14%) and increase of plutonic-metamorphic and palaeovolcanic detritus.The Upper Topanga Group (Calabasas Formation), conformably overlying the Middle unit, has dominantly plutoniclastic sandstone (petrofacies 6). Neovolcanic detritus is drastically reduced (4%) whereas palaeovolcanic detritus is similar to percentages of the Lower Topanga Group (petrofacies 1).In general, the volcaniclastic contribution represents a well-defined marker in the sedimentary record. Detailed compositional study of volcaniclastic strata and volcanic particles (including both compositional and textural attributes) provides important constraints on deciphering spatial (extrabasinal vs. intrabasinal) and temporal relationships between neovolcanic events (pre-, syn-, inter- and post-eruptive periods) and older detritus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3091.1995.tb00409.x
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  • 2
    Electronic Resource
    Electronic Resource
    The effects of source lithology, transport, deposition and sampling scale on the composition of southern California sand (1997)
    Oxford, UK : Blackwell Publishing Ltd
    Sedimentology 44 (1997), S. 0 
    Details
    ISSN: 1365-3091
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: The Transverse Ranges of southern California represent an uplifted and variably dissected Mesozoic magmatic arc, and Mesozoic to Holocene sedimentary and volcanic strata deposited in convergent and transform tectonic settings. Modern sand within part of the Western Transverse Ranges represents: first-order sampling scale of the Santa Monica and the San Gabriel Mountains; second-order sampling scale of the Santa Clara River draining both mountain ranges; and third-order sampling scale of the beach system between the mouth of the Santa Clara River and the eastern Santa Monica Mountains, and turbidite sand of the Hueneme-Mugu submarine fan.Source lithology includes plutonic and metamorphic rocks of the San Gabriel Mountains, and sedimentary and volcanic rocks of the Santa Monica Mountains. First-order sands have large compositional variability. Sand from local coastal drainage of the Santa Monica Mountains ranges from basaltic feldspatholithic to quartzofeldspathic. Sand of the San Gabriel Mountains local drainages has three distinct petrofacies, ranging from metamorphiclastic feldspatholithic to mixed metamorphi/plutoniclastic and plutoniclastic quartzofeldspathic. Second-order sand is represented by the main channel of the Santa Clara River; the sand has an abrupt downstream compositional change, from feldspathic to quartzofeldspathic. Third-order sand (beaches and deep-sea turbidite samples) of the Santa Monica Basin is quartzofeldspathic. Beach sand is more quartz-rich than is Santa Clara river sand, whereas turbidite sand is more feldspar-rich than is beach sand. Deep-sea sand has intermediate composition with respect to second-order samples of the Santa Clara River and third-order samples of the beach system, suggesting that (1) the Santa Clara River is the main source of sediments to the marine environment; and (2) local entry points from canyons located near local drainages may generate turbidity currents during exceptional flood conditions. Petrologic data of modern sand of the study area are highly variable at first- and second-order scale, whereas third-order sand is homogenized. The homogenized composition of deep-marine sand is similar to the composition of most ancient sandstone derived primarily from the Mesozoic dissected magmatic arc of southern California. This study of the Western Transverse Ranges illustrates the effects of source lithology, transport, depositional environment, and sampling scale on sand composition of a complex system, which provides insights regarding actualistic petrofacies models.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-3091.1997.d01-42.x
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  • 3
    Electronic Resource
    Electronic Resource
    Efficient modification of the APRT gene by FLP/FRT site-specific targeting (1995)
    Springer
    Somatic cell and molecular genetics 21 (1995), S. 299-307 
    Details
    ISSN: 1572-9931
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The FLP/FRT site-specific recombination system was established and characterized at the APRT gene in CHO cells. Targeting frequencies with FLP-stimulation were about 1 to 5×10−5, which were 6–22-fold above gene targeting frequencies in the absence of FLP. Fifty two APRT+ cell lines were analyzed by Southern blotting: 56% were FLP-targeted integrants; 33% were APRT target convertants; 11% gave undefined patterns. In separate experiments we first enriched for integrants by screening for two additional markers carried on the targeting vector; 18 of 19 (95%) of the resulting cell lines were integrants. Intrachromosomal site-specific recombination was tested by reexposing integrants to FLP. Intrachromosomal popouts were stimulated over 200-fold, while homologous recombination in an adjacent interval was unchanged. The utility of this system was demonstrated by one-step FLP targeting to generate chromosomal substrates for homologous recombination, and by a two-step, FLP-and-run procedure to construct a chromosomal substrate for illegitimate recombination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02257465
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  • 4
    Electronic Resource
    Electronic Resource
    Reassessment of the roles of the peritrophic envelope and hydrolysis in protecting polyphagous grasshoppers from ingested hydrolyzable tannins (1996)
    Springer
    Journal of chemical ecology 22 (1996), S. 1901-1919 
    Details
    ISSN: 1573-1561
    Keywords: Orthoptera ; Acrididae ; grasshopper ; Melanoplus sanguinipes ; Phoetaliotes nebrascensis ; peritrophic envelope ; peritrophic membrane ; hydrolyzable tannin ; tannic acid ; oxidation ; hydrolysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract We examined several of the mechanisms that have been reported to enable polyphagous grasshoppers (Orthoptera: Acrididae) to tolerate ingested hydrolyzable tannins: hydrolysis, adsorption on the peritrophic envelope, and peritrophic envelope impermeability. None of these mechanisms explain the tolerance ofMelanoplus sanguinipes to ingested tannic acid. In this species, tannin hydrolysis was 12–47% complete, adsorption accounted for less than 1% of the tannic acid contained in the midgut, and the peritrophic envelope was permeated by several gallotannins. The foregut is the main site for the chemical transformation of tannic acid in this species. InPhoetaliotes nebrascensis, hydrolysis was more extensive (82% complete), but the peritrophic envelope was readily permeated by two gallotannins. Oxidizing redox conditions were found in the guts of both species, and ingested tannins were oxidized inM. sanguinipes. We hypothesize that the tolerance of some polyphagous grasshoppers to ingested hydrolyzable tannins may be the consequence of their ability to tolerate the reactive oxygen species generated by polyphenol oxidation, whereas others may rely on rapid and extensive hydrolysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02028511
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  • 5
    Electronic Resource
    Electronic Resource
    Evaluation of an Air Force Child Physical Abuse Prevention Project Using the Reliable Change Index (1997)
    Springer
    Journal of child and family studies 6 (1997), S. 421-434 
    Details
    ISSN: 1573-2843
    Keywords: child physical abuse ; abuse prevention ; Common Sense Parenting® program ; family relationships ; Jacobson's Reliable Change Index
    Source: Springer Online Journal Archives 1860-2000
    Topics: Psychology , Sociology
    Notes: Abstract Three hundred and seventy-nine parents at 25 Air Force bases participated in a collaborative child physical abuse prevention project designed by the United States Air Force Family Advocacy Program and Father Flanagan's Boys' Home (Boys Town). These participants were active duty or civilian employee parents and their spouses who completed the Boys Town Common Sense Parenting ® program as part of a comprehensive prevention effort. We hypothesized that participants would report decreased child behavior problems, improved relationships with family members, and reduced risk for child physical abuse after attending parenting sessions. Results supported this hypothesis. The data were also analyzed to determine the frequencies of individual parents who made statistically reliable changes on the dependent measures using Jacobson's Reliable Change Index. Nineteen to 30% of the participants reported significant improvement in the areas assessed. Parents who improved in abuse risk were at a higher level of risk and were less satisfied with family relationships prior to their participation than those who did not change. Implications for prevention of child physical abuse and future directions for research are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1025093328618
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    Paper (German National Licenses)
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  • 6
    Electronic Resource
    Electronic Resource
    A cost-effectiveness evaluation of parent training (1996)
    Springer
    Journal of child and family studies 5 (1996), S. 415-429 
    Details
    ISSN: 1573-2843
    Keywords: parent training ; program evaluation ; cost-effectiveness ; clinical significance ; mental health
    Source: Springer Online Journal Archives 1860-2000
    Topics: Psychology , Sociology
    Notes: Abstract Outcomes from a parenting program that was modified to reduce costs and a wait-list control condition were compared. Costs were reduced by over 50%. Sixty-six parents participated. Treatment parents reported significantly greater improvements in child behavior problems, parent attitudes, and satisfaction with family relationships when compared to untreated controls. These effects were maintained at three months follow-up. Outcomes for 35 of the children in the sample who had clinically significant behavior problems before treatment were also examined separately. The difference between clinical recovery rates, i.e., movement from the clinical to normal range during treatment, for control and treatment children was not statistically significant. Limitations of the current study and suggestions for future research are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02233863
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