Freedom of expression. Introduction to special issue     

Riddihough G  Purnell BA  Travis J 《Science (New York, N.Y.)》2008,319(5871):1781

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Comparative ecology: ecology and natural history of desert lizards     

Travis J 《Science (New York, N.Y.)》1987,235(4787):492b-493b

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MUSCULAR FIXATION OF THE STUTTERER'S VOICE UNDER EMOTION     

Travis LE 《Science (New York, N.Y.)》1925,62(1600):207-208

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Enterprises of chemistry     

Travis AS 《Science (New York, N.Y.)》1991,254(5031):588

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A life with grapes     

Travis J 《Science (New York, N.Y.)》2008,320(5875):476-477

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Mapping human brain monoamine oxidase A and B with 11C-labeled suicide inactivators and PET   总被引：1，自引：0，他引：1  

J S Fowler  R R MacGregor  A P Wolf  C D Arnett  S L Dewey  D Schlyer  D Christman  J Logan  M Smith  H Sachs 《Science (New York, N.Y.)》1987,235(4787):481-485

The regional distributions of monoamine oxidase (MAO) types A and B have been identified in human brain in vivo with intravenously injected 11C-labeled suicide enzyme inactivators, clorgyline and L-deprenyl, and positron emission tomography. The rapid brain uptake and retention of radioactivity for both 11C tracers indicated irreversible trapping. The anatomical distribution of 11C paralleled the distribution of MAO A and MAO B in human brain in autopsy material. The corpus striatum, thalamus, and brainstem contained high MAO activity. The magnitudes of uptake of both [11C]clorgyline and L-[11C]deprenyl were markedly reduced in one subject treated with the antidepressant MAO inhibitor phenelzine. A comparison of the brain uptake and retention of the 11C-labeled inactive (D-) and active (L-) enantiomers of deprenyl showed rapid clearance of the inactive enantiomer and retention of the active enantiomer within MAO B-rich brain structures, in agreement with the known stereoselectivity of MAO B for L-deprenyl. Prior treatment with unlabeled L-deprenyl prevented retention of L-[11C]deprenyl. Thus, suicide enzyme inactivators labeled with positron emitters can be used to quantitate the distribution and kinetic characteristics of MAO in human brain structures.  相似文献   

Genetic regulation of conidiation in Trichoderma hamatun          下载免费PDF全文

Johanna Steyaert　 Travis Glare　 Alison Stewart　 Margaret Carpenter　 Hayley Ridgway 《浙江大学学报(农业与生命科学版)》2004,30(4):442-442

Achieving a balance between vegetative growth and spore production is essential for successful biocontrol by fungi. Low sporulation rates in the field can result in poor establishment and survival,whereas failure of conidia to recognise hosts can lead to persistence without efficacy. Commercial biocontrol products involve bulk preparations of conidia, however considerable variability in conidiation rates exists between biocontrol agents, which can restrict choice of strain for production. The majority of studies on Trichoderma conidiation have focused on the species T. viride and T. atroviride.These species form conidia in response to blue and near-UV light and/or nutrient deprivation and conidiation proceeds in a highly co-ordinated fashion, however relatively little is known on the genetic basis of Trichoderrma conidiation. In addition, whilst photoconidiation appears to be a general response detailed studies in other Trichoderma species are absent. In this study, conidiation in the lesser known biocontrol species T. hamatum is being investigated using a combined morphological and molecular approach. In contrast to T. atroviride, conidiation in response to blue-light was weaker and variable and suggested that additional triggers may be required for the T. hamatum photoresponse. A series of comparative photoconidiation assays are currently being undertaken investigating the effect of inoculum type and abiotic factors on timing and intensity of the response.Results will be discussed in relation to the current knowledge on conidial morphogenesis in Trichoderma. In addition to these morphological assays, a selection of genes implicated in sporulation and the blue-light responses are currently being isolated and characterised from T. hamatum. Two genes, phr1 and cmp1 , which were isolated previously from T. atroviride will be used as early and late markers of gene expression during the photoresponse in T. hamatum in order to define time points for harvesting comparable stage-specific RNA from T. hamatum and T. atroviride. Using degenerate PCR putative sporulation gene orthologues have also been identified in T. hamatum.Work is currently underway to isolate genomic clones of these genes from T. hamatum and T.atroviride. Sequence and expression analysis of orthologues, including expression in response to abiotic factors will be presented and discussed in relation to the current knowledge of the molecular basis of conidiation in Trichoderma and other filamentous fungi.……  相似文献   

Observation of shoemaker-levy impacts by the galileo photopolarimeter radiometer     

Martin TZ  Orton GS  Travis LD  Tamppari LK  Claypool I 《Science (New York, N.Y.)》1995,268(5219):1875-1879

The Galileo Photopolarimeter Radiometer experiment made direct photometric observations at 678 and 945 nanometers of several comet Shoemaker-Levy 9 fragments impacting with Jupiter. Initial flashes occurred at (fragment G) 18 July 1994 07:33:32, (H) 18 July 19:31:58, (L) 19 July 22:16:48, and (Q1) 20 July 20:13:52 [equivalent universal time coordinated (UTC) observed at Earth], with relative peak 945-nanometer brightnesses of 0.87, 0.67, 1.00, and 0.42, respectively. The light curves show a 2-second rise to maximum, a 10-second plateau, and an accelerating falloff. The Q1 event, observed at both wavelengths, yielded a color temperature of more than 10,000 kelvin at its peak.  相似文献   

Long-term satellite record reveals likely recent aerosol trend     

Mishchenko MI  Geogdzhayev IV  Rossow WB  Cairns B  Carlson BE  Lacis AA  Liu L  Travis LD 《Science (New York, N.Y.)》2007,315(5818):1543

Analysis of the long-term Global Aerosol Climatology Project data set reveals a likely decrease of the global optical thickness of tropospheric aerosols by as much as 0.03 during the period from 1991 to 2005. This recent trend mirrors the concurrent global increase in solar radiation fluxes at Earth's surface and may have contributed to recent changes in surface climate.  相似文献   

Schools stumble on an afrocentric science essay     

Travis J 《Science (New York, N.Y.)》1993,262(5136):1121-1122

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