877 resultados para Twentieth-century literature


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This thesis is about plant breeding in Early 20th-Century Italy. The stories of the two most prominent Italian plant-breeders of the time, Nazareno Strampelli and Francesco Todaro, are used to explore a fragment of the often-neglected history of Italian agricultural research. While Italy was not at the forefront of agricultural innovation, research programs aimed at varietal innovation did emerge in the country, along with an early diffusion of Mendelism. Using philosophical as well as historical analysis, plant breeding is analysed throughout this thesis as a process: a sequence of steps that lays on practical skills and theoretical assumptions, acting on various elements of production. Systematic plant-breeding programs in Italy started from small individual efforts, attracting more and more resources until they became a crucial part of the fascist regime's infamous agricultural policy. Hybrid varieties developed in the early 20th century survived World War II and are now ancestors of the varieties that are still cultivated today. Despite this relevance, the history of Italian wheat hybrids is today largely forgotten: this thesis is an effort to re-evaluate a part of it. The research did allow previously unknown or neglected facts to emerge, giving a new perspective on the infamous alliance between plant-breeding programs and the fascist regime. This thesis undertakes an analysis of Italian plant-breeding programs as processes. Those processes had a practical as well as a theoretical side, and involved various elements of production. Although a complete history of Italian plant breeding still remains to be written, the Italian case can now be considered along with the other case-studies that other scholars have developed in the history of plant breeding. The hope is that this historical and philosophical analysis will contribute to the on-going effort to understand the history of plants.

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In this groundbreaking book Christian Gerlach traces the social roots of the extraordinary processes of human destruction involved in mass violence throughout the twentieth century. He argues that terms such as 'genocide' and 'ethnic cleansing' are too narrow to explain the diverse motives and interests that cause violence to spread in varying forms and intensities. From killings and expulsions to enforced hunger, collective rape, strategic bombing, forced labour and imprisonment he explores what happened before, during, and after periods of widespread bloodshed in countries such as Armenia, Indonesia, Bangladesh, Nazi-occupied Greece and in anti-guerilla wars worldwide in order to highlight the crucial role of socio-economic pressures in the generation of group conflicts. By focussing on why so many different people participated in or supported mass violence, and why different groups were victimized, he offers us a new way of understanding one of the most disturbing phenomena of our times.

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Extension of 3-D atmospheric data products back into the past is desirable for a wide range of applications. Historical upper-air data are important in this endeavour, particularly in the maritime regions of the tropics and the southern hemisphere, where observations are extremely sparse. Here we present newly digitized and re-evaluated early ship-based upper-air data from two cruises: (1) kite and registering balloon profiles from onboard the ship SMS Planet on a cruise from Europe around South Africa and across the Indian Ocean to the western Pacific in 1906/1907, and (2) ship-based radiosonde data from onboard the MS Schwabenland on a cruise from Europe across the Atlantic to Antarctica and back in 1938/1939. We describe the data and provide estimations of the errors. We compare the data with a recent reanalysis (the Twentieth Century Reanalysis Project, 20CR, Compo et al., 2011) that provides global 3-D data back to the 19th century based on an assimilation of surface pressure data only (plus monthly mean sea-surface temperatures). In cruise (1), the agreement is generally good, but large temperature differences appear during a period with a strong inversion. In cruise (2), after a subset of the data are corrected, close agreement between observations and 20CR is found for geopotential height (GPH) and temperature notwithstanding a likely cold bias of 20CR at the tropopause level. Results are considerably worse for relative humidity, which was reportedly inaccurately measured. Note that comparing 20CR, which has limited skill in the tropical regions, with measurements from ships in remote regions made under sometimes difficult conditions can be considered a worst case assessment. In view of that fact, the anomaly correlations for temperature of 0.3–0.6 in the lower troposphere in cruise (1) and of 0.5–0.7 for tropospheric temperature and GPH in cruise (2) are considered as promising results. Moreover, they are consistent with the error estimations. The results suggest room for further improvement of data products in remote regions.

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Meteorological or climatological extremes are rare and hence studying them requires long meteorological data sets. Moreover, for addressing the underlying atmospheric processes, detailed three-dimensional data are desired. Until recently the two requirements were incompatible as long meteorological series were only available for a few locations, whereas detailed 3-dimensional data sets such as reanalyses were limited to the past few decades. In 2011, the “Twentieth Century Reanalysis” (20CR) was released, a 6-hourly global atmospheric data set covering the past 140 years, thus combining the two properties. The collection of short papers in this volume contains case studies of individual extreme events in the 20CR data set. In this overview paper we introduce the first six cases and summarise some common findings. All of the events are represented in 20CR in a physically consistent way, allowing further meteorological interpretations and process studies. Also, for most of the events, the magnitudes are underestimated in the ensemble mean. Possible causes are addressed. For interpreting extrema it may be necessary to address individual ensemble members. Also, the density of observations underlying 20CR should be considered. Finally, we point to problems in wind speeds over the Arctic and the northern North Pacific in 20CR prior to the 1950s.