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1.
The global phenomenon of maritime expansion and the measures of control imposed by the interventionism of the Iberian crowns generated a context that sheds light on the Zilselian issue: the contact between artisans and university‐trained men in early modern Europe. This is an old and controversial topic. However, this article does not focus solely on the economic and social reasons for this contact, but also on epistemological and political motivations. With the specific aim of illustrating this collaboration, the article analyses some of the empirical practices developed under the Portuguese maritime empire throughout the 16th century. This is achieved through the reconstruction of the process of production of nautical charts in the Armazéns da Guiné e Índia (Storehouse of Guinea and Indies) of Lisbon, which I consider a large‐scale “trading zone.” This reconstruction throws light not only on the technical complexity of these cognitive processes and the coordinated work of the different agents involved in their production, but also on the emergence of new spaces of knowledge and new communities of practitioners (with new professional statuses) linked to them; new methods of collection and management of information; and, finally, new forms of circulation and standardization of knowledge in the early modern period.  相似文献   
2.
Musculoskeletal disorders (MSD) have a high impact on the health of dual role workers (student and work). The aim of this study was to analyse risk factor (active pauses and job position) associated with MSD in postgraduate students, Bogotá 2016. This Cross-sectional study was conducted in a random sample of 304 college graduate students and statistical analysis in SPSS version 24. We found that significant differences between non-performing active pauses and neck symptoms (P = 0.007), not stretching vs neck symptoms [OR = 2.4048 (1.0133–5.707)]; laptop use vs eyes [OR = 2.7132 (1.457–5.0526)], shoulders [OR = 10.6364 (4.9905–22.6697)], elbows (P = 0.04); non-mouse usage vs elbows (P = 0.028), hand-wrist (P = 0.043); non-forearm support vs lower back (P = 0.009). Results suggest association between non-performing active pauses, stretching and neck; use of laptop and eyes, shoulders and left elbow, non-mouse usage and on elbow and hand/right wrist, no forearm support on table and lower back. Symptom changes in the upper and lower limbs were identified.  相似文献   
3.
Differentiating between the static impulse to preserve and the more open-ended and imaginative process of conservation, Federica Goffi presents a building as ‘a fabric that, even when complete, is unfinished and open to change’. Associate Professor and Associate Director of Graduate Programs at the Azrieli School of Architecture and Urbanism at Carleton University in Ottawa, Goffi has written widely on the topic of time, particularly taking St Peter's in the Vatican by way of example.  相似文献   
4.
An awakening interest in public space in Brazilian cities is emphasising the value of existing civic areas. Guilherme Wisnik , a critic, curator and professor at the Faculty of Architecture and Urbanism of the University of São Paulo, looks at the history and potential future of Brazil's urban spaces. He highlights how despite the introduction of innovative Modernist design in the mid-20th century, which forged ‘a new relationship between architecture, urbanism and landscape design’, more recently the country's cities have been subject to the vicissitudes of market and political forces.  相似文献   
5.
The present study aimed at evaluating the growth of Escherichia coli, Salmonella enterica, and Listeria spp. and studying the efficacy of Ultraviolet-C (UV-C) irradiation, acidic electrolyzed (AEW) and neutral electrolyzed (NEW) waters in the reduction of these bacteria on ‘Rocha’ pear. Fresh-cut pieces were inoculated and incubated at 4–20 °C for 8 days. Inoculated pears were treated with UV-C (2.5–10 kJ/m2), AEW, NEW and sodium hypochlorite (SH) and microbiological and quality parameters were evaluated. The three bacteria, inoculated at 6.1–6.2 log cfu/g, grew on the pear at high growth rates at 12 and 20 °C reaching populations of 8.1–8.6 log cfu/g, in 24 h. At 8 °C the microorganisms increased their populations by at least 1 log cfu/g in three days. At 4 °C adaptation phases of less than 24 h for Listeria spp. were measured before exponential growth occurred and the enterobacteria did not grow despite having survived for 8 days. AEW and NEW caused microbial reductions similar to SH, of approximately 1 log cfu/g, while the best UV-C dose (7.5 kJ/m2) of at least 2.4 log cfu/g. Fresh-cut pears were a good substrate for foodborne bacteria emphasizing the importance of preventing contaminations and cross contaminations. The UV-C was more effective than the chemical decontaminations, as it provided superior microbial reductions without greatly affecting the quality of pears.  相似文献   
6.
An evaluation and inventory study on the natural vegetation cover and its diversity was carried out on the forest vegetation of the district of Saïda. The floristic diversity of our study area revealed the existence of 397 taxa belonging to 64 families and 271 genera. The most important families are Asteraceae (42 genera), Fabaceae (25 genera), Brassicaceae (22 genera) and Poaceae (22 genera). The category of rare taxa represents 13% of the studied flora (52 taxa). In our study area, we have counted 35 endemic regional species of which 19 species are endemic Algerian-Moroccan, and 3 species are strictly endemic to Algeria. Among the taxa analysed, 02 are included in the IUCN Red List, and 12 are on the Algerian list of protected non-cultivated plant species.  相似文献   
7.
The concept is proposed for a knowledge-based standardization in fracture at high temperature. Examples are presented of the high temperature creep growth and fracture life, and the testing methodology of hard brittle materials with notch is discussed.  相似文献   
8.
9.
提出了在水平井中运用生物酶解除钻井液对地层造成的伤害 ,详细阐述了生物酶的作用机理。通过室内粘度降低、滤饼清除和渗透率恢复等评价实验 ,及中东地区三口多油层井的现场对比实验 ,证明了运用生物酶作为破胶剂处理水平井钻井液对地层伤害的优越性  相似文献   
10.
采用无皂乳液分步聚合法合成了一系列LIPN阻尼材料,利用动态粘弹谱研究了其动态力学性能。结果表明:网络组分的相容性对阻尼性能的影响显,第三个网络的引入,显地改善了网络组分间的相容性,得到了阻尼性能优良的材料;交联剂用量在一定范围内变化有助于提高涂膜的阻尼性能;通过引入含羧基的共聚组分,提高了材料的高温阻尼性能。  相似文献   
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