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The turbulent climate of the Great Plains made windbreaks necessary for the protection of settlers and their livestock and crops. At first individual farmers tried to plant their own shelterbelts but with little success. The US Forest Service, with the establishment of the Bessey tree nursery, in 1902, and the field planting of the Nebraska National Forest, developed the expertise to carry out farm forestry on the plains. In 1934 the Forest Service undertook the Prairie States Forestry Project, an eight‐year program to plant shelterbelts from Canada to Texas, in response to the Dust Bowl and the Great Depression. These shelterbelts were a technological solution to environmental and social problems. As they grew, successful shelterbelts developed forest characteristics and served as habitat for birds and wildlife. As systems that were both technical and ecological, shelterbelts embodied a confluence of culture and nature in the technology that farmers and foresters used to engineer a more suitable environment for American society on the Plains.  相似文献   
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The Massachusetts Institute of Technology in 2000 initiated a billion dollar building program featuring buildings by world‐renowned architects, including Frank Gehry and Steven Holl. Gehry’s Stata Center, which houses computer scientists, and Holl’s Simmons Hall dormitory raise questions about the relationship of architecture to MIT’s values. Many MIT faculty, students, and administrators celebrate Gehry’s Stata and Holl’s Simmons as expressing the inventiveness, energy, and excellence of the people within them and as moving the campus into the twenty‐first century. Others ask if MIT has lost its way by choosing elite, costly buildings at an institution historically characterized by utilitarian and functional values.  相似文献   
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From 1990 to 1999, the House of Representatives held roll call votes to attempt to overturn presidential extensions of Normal Trade Relation (NTR) status to China. What was once a routine matter attracting little congressional attention became a highly divisive matter. Interestingly, the coalition that formed to oppose such extensions was a partnership of strange bedfellows: extreme liberals joining their far-right colleagues to try to rescind the president's extension of normal trade status for China. When the distribution of opposition on the yearly extensions of NTR is compared to that on the vote to approve permanent NTR (PNTR) for China, the ideological distribution of opponents changes noticeably. I argue that important procedural differences between the votes on the yearly extension, and PNTR, serve to explain why ideologically extreme members formed their strange alliance.  相似文献   
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The thirteenth-century Spanish poem Libro de Apolonio (LA) shares many features with other works of the cuaderna vía; among them is the frequency with which the personified figure of sin makes its appearance. One finds the word pecado in the opening scene of the LA, where the narrator says that sin, always restless, manages to stir up desire in King Antioco and makes him turn his gaze on his own daughter (6). Soon again, in reference to the same incestuous king, the narrator writes that “metiólo en locura la muebda del pecado” (26). With two early references in the LA to sinful impulses, the narrator suggests that pecado is the root cause of Byzantine-like adventures that take Apolonio across the Mediterranean world. To further underscore its importance, the author uses the word pecado in a variety of contexts a minimum of thirty-one times. Given its near omnipresence, it is essential that one consider the nature and role of sin when interpreting the work. As a window through which to view sin, this essay focuses on the hero’s status as king. If Apolonio is referred to as pilgrim on occasion, it is no less significant that the main character is referred to as king no less than thirty-five times in the work. It could be that the author wants us to bear in mind that we are not dealing with “everyman,” but with a king. By viewing Apolonio in this light, one can proceed to examine his royal performance to assess to what degree his shortcomings might be considered pecado.  相似文献   
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