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71.
Languages vary enormously in global importance because of historical, demographic, political, and technological forces. However, beyond simple measures of population and economic power, there has been no rigorous quantitative way to define the global influence of languages. Here we use the structure of the networks connecting multilingual speakers and translated texts, as expressed in book translations, multiple language editions of Wikipedia, and Twitter, to provide a concept of language importance that goes beyond simple economic or demographic measures. We find that the structure of these three global language networks (GLNs) is centered on English as a global hub and around a handful of intermediate hub languages, which include Spanish, German, French, Russian, Portuguese, and Chinese. We validate the measure of a language’s centrality in the three GLNs by showing that it exhibits a strong correlation with two independent measures of the number of famous people born in the countries associated with that language. These results suggest that the position of a language in the GLN contributes to the visibility of its speakers and the global popularity of the cultural content they produce.Of the thousands of languages that have ever been spoken, only a handful have become influential enough to be considered global languages. However, how do we measure the global influence of a language? What are the implications of a world in which only a handful of languages are globally influential?In the past, researchers have used a variety of measures to determine the global influence of a language. Several studies have relied on measures that proxy the global influence of a language using the population and wealth of its speakers (14). While wealth and population approximate a language’s influence, as the dissemination of a language has historically required a strong power base (5), such measures fail to capture the global influence of a language: often the speakers of a language, and their wealth, are locally concentrated, making the language locally influential rather than globally influential.An alternative method to measure the global influence of a language is to focus on who speaks that language, and in particular, on how connected the speakers of that language are. In the words of linguist David Crystal, “Why a language becomes a global language has little to do with the number of people who speak it. It is much more to do with who those speakers are.” (5) In the past, Latin was the pan-European language, not because it was the mother tongue of most Europeans, but because it was the language of the Roman Empire and later the language of the Catholic Church, scholars, and educators (5). The use of Latin by well-connected elites set it apart from other languages and helped Latin endure as a universal language for more than 1,000 years.However, can we use these ideas to identify which modern languages are globally influential? If global languages are those connecting international elites, then we can identify the global languages associated with particular elites by mapping their networks of multilingual coexpressions. Examples of multilingual coexpressions include book translations, edits to multiple language editions of Wikipedia, and posting short messages on Twitter (“tweets”) in multiple languages. These coexpressions define networks (Fig. 1) that—even though not representative of the world’s general population—represent a coarse map of the links connecting the elites that participate of these three important global forums, as social connections often require a shared language.Open in a separate windowFig. 1.Visualizations of the three GLNs. The three GLNs contain all language connections that involve at least six users (Twitter and Wikipedia) or six translations and that are significant with P < 0.01.In this paper, we map the global language networks (GLNs) expressed in three large records of linguistic expression, and use the structure of these networks to determine the degree to which each language is global. First, we look at a collection of more than 2.2 million book translations compiled by UNESCO’s Index Translationum project. This dataset allows us to map the network of book translations, which are produced by individuals with a high literary capacity (authors and professional translators) and are shaped by market forces, such as the demand for books in different languages. Each translation from one language to another forms a connection. Next, we map the network of linguistic coexpressions expressed by the community of digitally engaged knowledge specialists that edit Wikipedia. Here, two languages are connected when users that edit an article in one Wikipedia language edition are significantly more likely to also edit an article in another language edition. Finally, we map the network of linguistic coexpressions expressed in Twitter. Here, two languages are connected when users that tweet in a language are also significantly more likely to tweet in another language.These three networks allow us to map the paths of direct and indirect communication between speakers from different languages. Our method formalizes the intuition that certain languages are disproportionately influential because they provide direct and indirect paths of translation among most of the world’s other languages. For example, it is easy for an idea conceived by a Spaniard to reach an Englishman through bilingual speakers of English and Spanish. An idea conceived by a Vietnamese speaker, however, might only reach a Mapudungun speaker in south-central Chile through a circuitous path that connects bilingual speakers of Vietnamese and English, English and Spanish, and Spanish and Mapudungun. In both cases, however, English and Spanish are still involved in the flow of information, indicating that they act as global languages. In the first example, Spanish and English have a direct involvement because communication is flowing among their speakers. In the latter case, the involvement is indirect and emerges from the lack of speakers that can communicate in both Vietnamese and Mapudungun. These indirect connections make multilingual speakers of global languages globally influential, as they mediate the flow of information not only among each other, but also, among people with whom they do not share a language (6).  相似文献   
72.
Survival signaling by the erythropoietin (Epo) receptor (EpoR) is essential for erythropoiesis and for its acceleration in hypoxic stress. Several apparently redundant EpoR survival pathways were identified in vitro, raising the possibility of their functional specialization in vivo. Here we used mouse models of acute and chronic stress, including a hypoxic environment and β-thalassemia, to identify two markedly different response dynamics for two erythroblast survival pathways in vivo. Induction of the antiapoptotic protein Bcl-x(L) is rapid but transient, while suppression of the proapoptotic protein Bim is slower but persistent. Similar to sensory adaptation, however, the Bcl-x(L) pathway "resets," allowing it to respond afresh to acute stress superimposed on a chronic stress stimulus. Using "knock-in" mouse models expressing mutant EpoRs, we found that adaptation in the Bcl-x(L) response occurs because of adaptation of its upstream regulator Stat5, both requiring the EpoR distal cytoplasmic domain. We conclude that survival pathways show previously unsuspected functional specialization for the acute and chronic phases of the stress response. Bcl-x(L) induction provides a "stop-gap" in acute stress, until slower but permanent pathways are activated. Furthermore, pathologic elevation of Bcl-x(L) may be the result of impaired adaptation, with implications for myeloproliferative disease mechanisms.  相似文献   
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Interleukin (IL)‐6 is crucial for the induction of many murine models of autoimmunity including experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. While IL‐6‐deficient mice (IL‐6 KO) are resistant to EAE, we showed previously that in transgenic mice with astrocyte‐targeted production of IL‐6‐restricted to the cerebellum (GFAP‐IL6), EAE induced with MOG35–55 was redirected away from the spinal cord to the cerebellum. To further establish the importance of IL‐6 produced in the central nervous system, we have generated mice producing IL‐6 essentially only in the brain by crossing the GFAP‐IL6 mice with IL‐6 KO mice. Interestingly, GFAP‐IL6‐IL‐6 KO mice showed a milder but almost identical phenotype as the GFAP‐IL6 mice, which correlated with a lower load of inflammatory cells and decreased microglial reactivity. These results indicate that not only is cerebellar IL‐6 production and eventual leakage into the peripheral compartment the dominating factor controlling this type of EAE but that it can also facilitate induction of autoimmunity in the absence of normal systemic IL‐6 production. © 2013 Wiley Periodicals, Inc.  相似文献   
79.
Leon P  Chedraui P  Hidalgo L  Ortiz F 《Maturitas》2007,57(3):233-238
BACKGROUND: Studies reporting the perspective of Latin American women, Ecuador, included, regarding the menopausal phenomena are scarce or lacking. OBJECTIVES: Obtain information regarding the perception and attitudes toward the menopause among middle aged women of Guayaquil, Ecuador. METHODS: Women aged 40 or more, nursing staff members of two major associated teaching hospitals of the Universidad Católica de Santiago de Guayaquil, Ecuador, were surveyed with a structured questionnaire containing items intended to assess women's perception and attitudes toward the menopause. Secondarily level of information related to the menopause was explored. RESULTS: During the study period, 349 women were surveyed of which mean age was 48+/-6.8 years. A 41.3% were postmenopausal, 55% premenopausal and 3.7% had a history of hysterectomy with conserved ovaries. Women more frequently perceived the menopause as a positive event as they agreed that it is a normal (93.7%) and important event (73.6%), that it gives more confidence and maturity (78.8%), that they may fully enjoy sexual relations (74.8%), that there is a relief as the risk of becoming pregnant is null (65.3%) and that life becomes easier and calmer (60.7%). A relatively high rate demonstrated a preoccupying attitude toward the menopause as 79.4% responded to be concerned about it indicating that seeking medical attention was important, moreover, 77.9% responded that health during this phase be taken care of and life styles changed. Less than 50% of surveyed women considered having enough information regarding the menopause whereas a high rate indicated wanting to receive educational sessions related to the menopause. Married and lower educated women were not concerned about the menopause in a higher rate than their counterparts. CONCLUSIONS: Despite the fact that women perceived the menopause as a positive event, displaying a concerned attitude toward it, their related knowledge was low.  相似文献   
80.
α-葡萄糖苷酶抑制剂治疗2型糖尿病的系统评价   总被引:4,自引:0,他引:4  
目的评价α-葡萄糖苷酶抑制剂治疗2型糖尿病患者的效果。方法检索Cochrane图书馆、MEDLINE、EMBASE、CurrentContents、LILACS在研试验数据库,主题为α-葡萄糖苷酶抑制剂的综述的参考文献,并联系纳入试验的专家与实施者。最近检索日期为2003年月12月(CurrentContents)和2003年4月(其他数据库)。纳入α-葡萄糖苷酶抑制剂单一疗法与其它干预比较,治疗2型糖尿病疗程至少12周的随机对照试验,并且试验至少包括以下结局之一:病死率、患病率、生活质量、血糖控制、血脂、胰岛素水平、体重、不良事件。两名评价者独立阅读所有摘要,评价质量并提取数据,分歧通过协商解决或由第三位评价者裁决。由一位统计学家在对提取数据输入数据库时进行检查。我们尽量联系所有作者以核实数据。结果共纳入41个试验、8130例受试者,其中30个针对阿卡波糖,7个针对米格列醇,1个针对优格列波糖,还有3个为不同α-葡萄糖苷酶抑制剂间的比较。绝大多数研究疗程为24周,仅有2个研究超过1年。与安慰剂相比,阿卡波糖血糖控制效果更好:糖化血红蛋白–0.8%[95%CI(–0.9,–0.7)],空腹血糖–1.1mmol/L[95%CI(–1.4,–0.9)],负荷血糖–2.3mmol/L[95%CI(–2.7,–1.9)],阿卡波糖对糖化血红蛋白的作用呈非剂量依赖。我们发现其可降低负荷胰岛素,但对血脂和体重未见临床相关的作用。不良反应主要来自胃肠道且与剂量相关。相对于磺脲,阿卡波糖将空腹和负荷胰岛素水平分别降低至–24.8pmol/L[95%CI(–43.3,–6.3)]和–133.2pmol/L[95%CI(–184.5,–81.8)],但阿卡波糖引起的不良反应更多。结论关于α-葡萄糖苷酶抑制剂是否影响2型糖尿病患者的病死率和患病率仍不清楚。相反,其对血糖控制或胰岛素水平作用明显,对血脂和体重的作用差异无统计学意义。α-葡萄糖苷酶抑制剂更长疗程的效果仍不确定。阿卡波糖剂量超过50mg(TID)时不能进一步影响糖化血红蛋白水平,不良反应反而更多,与磺脲相比,α-葡萄糖苷酶抑制剂降低了空腹和负荷胰岛素水平,但在血糖控制和不良反应方面存在不利影响。  相似文献   
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