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The paper deals with the transformation of plant breeding from an agricultural practice into an applied academic science in the late 19th and early 20th centuries Germany. The aim is to contribute to the ongoing debate about the relationship between science and technology. After a brief discussion of this debate the first part of the paper examines how pioneers of plant breeding developed their breeding methods and commercially successful varieties. The focus here is on the role of scientific concepts and theories in the agricultural innovation process. The second part turns towards the strategies by which agronomists tried to establish plant breeding as an academic discipline and themselves as the new experts for breeding research and varietal development. Again, the focus is on the interplay of scientific theory and agricultural practice. It is argued that in order to better understand the transformation of plant breeding into an applied academic science we have to take different levels into account, i.e. the levels of organizations, individuals and objects, at which science and technology interact.  相似文献   

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As for most of the mountainous areas even the Friulan Mountains between the 18th and the 19th century proved to be extremely deficient of consumer goods produce. To provide for the subsistence of the population it was therefore necessary to import great amounts of alimentary goods, cereals in particular. This paper will show how the agricultural prices influenced the mountainous areas; considerations will be made on the behaviour adopted by the populations of the valleys to counteract the negative impact brought about by the prices increases. A final look will outline the consequences of such behaviours at a demographic level. To this aim, after drawing a general picture of the mountain economy, an attempt will be made at quantifying the demand of the consumer goods. The system for cereals provision will be retraced and the relations between cereal prices and demongraphic variables will be evaluated.  相似文献   

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The creation of the Veterinary Schools in the 18th century would reveal a plethora of scientists, some of whom would be the precursors of Pasteur, some rivals, others followers collaborators or friends of the Master. Among the precursors let us name Chabbert, Huzard, Girard, Delafond, Renault, Toussaint, Galtier ; among the rivals: Chauveau, Arloing, Cornevin and Thomas; among the followers, collaborators or friends of Pasteur: Bouley, at first a resolute spontaneist, then the most fervent in defense of Pasteur (President of the Academy of Medicine and of the Academy of Sciences) and Nocard, Director of the School in Alfort, an important collaborator of Pasteur. Later, there was Leclainche, who created the International Office of Epizootics, and who was President of the Academy of Sciences; Guérin, who with Calmette developed the BCG vaccination; Ramon, the father of anatoxins (vaccines against diphtheria, and tetanus, combined vaccines, adjuvants to immunity). Thus, the creation of the Veterinary Schools contributed not only to the evolution of the notion of contagion, to the amelioration of animal health and the economics of agricultural production, but also to serious advances in human care, and to the protection of public health.  相似文献   

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Celebrating Ethnicity and Nation: American Festive Culture from the Revolution to the Early 20th Century. Jurgen Heideking. Genevieve Fabre. and Kai Dreisbach. eds. New York: Berghahn Books, 2001. 316 pp.  相似文献   

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This article proposes a new reading of early-19th-century modernity by examining India's so-called “ethnographic” paintings, and arguing that rather than participate in a trajectory of speed and acceleration these works produce colonial polyrhythmic temporality. First, the article establishes that many of these images depict action, not ethnicity or occupational group. It then situates these images in economies of circulation, viewing, politics and commercial enterprise. By focusing on the action in the subject matter—do-ing rather than do-er, processes rather than occupations—a layered, polyrhythmic range of temporalities emerges, upturning dualistic, acceleration-driven, and rupture-based understandings of visual culture from this period.  相似文献   

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回顾了上一世纪我国植物组织培养的发展.1934年以来,我国的植物组织培养研究一直与国际发展同步进行.我国学者在离体器官发生、茎尖培养、花药培养、子房培养、胚乳培养、原生质体培养和细胞大量培养等分支领域都取得重要进展.本文在引证我国研究者发表的植物组织培养论文的基础上,着重评述了那些被国际同行公认的研究成果.此外,还介绍了植物组织培养在我国农业和工业上应用的情况.  相似文献   

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Specific labelling with monoclonal antibodies reveals that in regulator-proteasome complexes the asymmetric 19S regulator (PA700) binds to one or both terminal alpha-disks of the cylinder-shaped 20S core proteasome in such a way that its reclining front part is positioned in the vicinity of proteasome subunit alpha6. The protruding rear part of the regulator appears to be situated distal to the sites occupied by the subunits alpha2 and alpha3, respectively. When viewed from beta1/beta1' to beta4/beta4' along the polar 2-fold axis of the 20S proteasome core, the rear part of each 19S regulator cap appears to protrude clockwise. Thus, a defined alignment of the 19S regulator with respect to the single polar 2-fold rotational axis of the 20S core proteasome is obtained.  相似文献   

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20th Century Carbon Budget of Forest Soils in the Alps   总被引:1,自引:1,他引:1  
Dendrochronological studies and forest inventory surveys have reported increased growth and biospheric carbon (C) sequestration for European forests in the recent past. The potential of concomitant changes in forest soil C stocks are not accounted for in the IPCC guidelines for national greenhouse gas inventories. We developed a model-based approach to address this problem and assess the role of soils in forest C balance in the European Alps. The decomposition model FORCLIM-D was driven by long-term (that is, 1900–1985 AD) litter input scenarios constructed from forest inventory data, region-specific dendrochronological basal area indices, and time series of anthropogenic litter removal. The effect of spatial climate variability on organic matter decomposition across the case study region (Switzerland) was explicitly accounted for by constant long-term annual means of actual evapotranspiration and temperature. Uncertainties in forest development, litter removal, fine root litter input, and dynamics of forest soil C were studied by an explorative factorial sensitivity analysis. We found that forest soils contribute substantially to the biospheric C sequestration for Switzerland: Our “best estimate” yielded an increase of 0.35 Mt C/y or 0.33 t C/(ha y) in forest soils for 1985, that is, 27% of the C sequestered by forest trees (BUWAL 1994). Uncertainties regarding C accumulation in forest soils were substantial (0.11–0.58 Mt C/y) but could be reduced by estimating forest soil C stocks in the future. Whereas soils can be important for the C balance in naturally regrowing forests, their C sequestration is negligible (less than 5%) relative to anthropogenic CO2 emissions in Western Europe at present. Received 25 August 1998; accepted 17 March 1999.  相似文献   

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The 20S Proteasome as an Assembly Platform for the 19S Regulatory Complex   总被引:1,自引:0,他引:1  
26S proteasomes consist of cylindrical 20S proteasomes with 19S regulatory complexes attached to the ends. Treatment with high concentrations of salt causes the regulatory complexes to separate into two sub-complexes, the base, which is in contact with the 20S proteasome, and the lid, which is the distal part of the 19S complex. Here, we describe two assembly intermediates of the human regulatory complex. One is a dimer of the two ATPase subunits, Rpt3 and Rpt6. The other is a complex of nascent Rpn2, Rpn10, Rpn11, Rpn13, and Txnl1, attached to preexisting 20S proteasomes. This early assembly complex does not yet contain Rpn1 or any of the ATPase subunits of the base. Thus, assembly of 19S regulatory complexes takes place on preexisting 20S proteasomes, and part of the lid is assembled before the base.  相似文献   

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