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91.
AbstractThe deployment of high-altitude vehicles in near space with the purpose of providing Internet, communication, and other services represents the new frontier of aerospace activities. Near-space operations are attracting growing interest due to their mult-purpose nature and their anticipated high profitability. Despite such positive perceptions, near-space plans are, however, hampered by the uncertain international legal status of near space. Using the precedent of the exclusive economic zone (EEZ), this article suggests a new categorization of the near space as the exclusive utilization space (EUS) and a set of rules to manage its utilization. 相似文献
92.
Replication of bovine papillomavirus vectors in murine cells 总被引:2,自引:0,他引:2
Margareta Waldenstrm Kerstin Schenstrm Kerstin Sollerbrant Lennart Hansson 《Gene》1992,120(2):175-181
93.
94.
Geostrategic Supply Risk and Economic Importance as Drivers for Implementation of Industrial Ecology Measures in a Nitrogen Fertilizer Production Company 下载免费PDF全文
Milda Malinauskienė Irina Kliopova Christoph Hugi Jurgis Kazimieras Staniškis 《Journal of Industrial Ecology》2018,22(2):422-433
Among other concerns, safeguarding the supply chains of raw materials is an important task for industrial companies. Therefore, not surprisingly, the number of scientific publications concerning the evaluation of resource criticality has increased in recent years. However, it was noticed that currently published methodologies are too complex to be applied by industrial companies on a daily basis. For this reason, the need to develop a methodology that would allow not only assessing resource criticality, but could also be integrated into widely applied methodological frameworks as an additional driver to improve resource efficiency was identified. Geostrategic supply risk and economic importance were chosen as key indicators to analyze and assess relative resource criticality. The developed methodology was field tested by applying it to a resource‐intensive nitrogen fertilizer production company. Five scenarios for resource efficiency improvements, consisting of cleaner production and industrial symbiosis measures, were investigated. If all the proposed measures were implemented, consumption of natural gas would decrease by 3.552 million cubic meters per year (0.3% of the total consumption). However, not all identified measures contribute to a reduction of the overall criticality of resources for the production company. Nevertheless, the integration of criticality assessments into the widely applied methodologies for development and implementation of resource efficiency innovations is a valuable addition and should be included in the analysis for sustainable innovations and development. 相似文献
95.
W. R. Pitchers R. Brooks M. D. Jennions T. Tregenza I. Dworkin J. Hunt 《Journal of evolutionary biology》2013,26(5):1060-1078
Phenotypic integration and plasticity are central to our understanding of how complex phenotypic traits evolve. Evolutionary change in complex quantitative traits can be predicted using the multivariate breeders’ equation, but such predictions are only accurate if the matrices involved are stable over evolutionary time. Recent study, however, suggests that these matrices are temporally plastic, spatially variable and themselves evolvable. The data available on phenotypic variance‐covariance matrix ( P ) stability are sparse, and largely focused on morphological traits. Here, we compared P for the structure of the complex sexual advertisement call of six divergent allopatric populations of the Australian black field cricket, Teleogryllus commodus. We measured a subset of calls from wild‐caught crickets from each of the populations and then a second subset after rearing crickets under common‐garden conditions for three generations. In a second experiment, crickets from each population were reared in the laboratory on high‐ and low‐nutrient diets and their calls recorded. In both experiments, we estimated P for call traits and used multiple methods to compare them statistically (Flury hierarchy, geometric subspace comparisons and random skewers). Despite considerable variation in means and variances of individual call traits, the structure of P was largely conserved among populations, across generations and between our rearing diets. Our finding that P remains largely stable, among populations and between environmental conditions, suggests that selection has preserved the structure of call traits in order that they can function as an integrated unit. 相似文献
96.
Nabil Khattab Ron Johnston Tariq Modood Ibrahim Sirkeci 《Ethnic and racial studies》2013,36(9):1466-1481
This paper expands the existing literature on ethnicity and economic activity in Britain by studying the impact of religion and class. It argues that while the class location of the different South-Asian groups is important in determining their labour market outcomes, it does not operate independently from ethnicity; rather it is highly influenced by ethnicity in the process of determining the labour market participation of these groups. We use data obtained from the 2001 UK Census on Indian, Pakistani, and Bangladeshi men and women aged between twenty and twenty nine. Our findings confirm that class structure of the South-Asian groups is highly ethnicized, in that the ethno-religious background and class are interwoven to the extent that the separation between them is not easy, if not impossible. 相似文献
97.
稻瘟病菌致病突变体的REMI诱变与鉴定 总被引:2,自引:0,他引:2
以水稻“爱知旭”(Aichi—aShahi)为寄主,将带选择标记的质粒pCSN43和pBF101为外源DNA,利用限制酶诱导整合(REMI)这种新方法转化稻瘟病菌原生质体,从筛选到的数百个转化体中分离出3个与致病能力密切相关的突变体R2H65、R2H69和R281565。其中,R2H65和R2H69只产生畸形分生孢子,分生孢子的发育和附着胞的形成以及黑色素的合成均受到极大影响,致病性测试证明完全丧失致病能力;R281565的许多表型与野生型的相似,但致病能力却大大降低。 相似文献
98.
Melissa Parks 《Science activities》2018,55(1-2):46-57
With school days seemingly getting shorter and packed with more and more obligations, teachers integrate core subjects like science and reading in the hopes of delivering a curriculum that is meaningful and content rich. Using trade books, primary teachers can develop and deliver science content designed to introduce students to proenvironmental behaviors built around the Next Generation Science Earth and Human Activity Standard, Human Impacts on Earth Systems, ESS3-C. The Next Generation Science standards call for integrating literacy skills and science to develop knowledge of scientific topics. This article shares ideas on how primary teachers can use a variety of children’s literature as a foundation to inspire young students to take small steps toward developing proenvironmental behaviors. Under an umbrella of three environmental themes, proenvironmental behavior, trash, and water pollution, the article describes key concepts, vocabulary, and activities designed to develop a mindfulness of proenvironmental behaviors for each selected text. While texts and learning experiences are intentionally focused on young learners (Kindergarten/first grade), they can be adapted and used in all primary grades. 相似文献
99.
T. Ren Z. Zhang R. Fu Y. Yang W. Li J. Liang G. Mo W. Luo X. Zhang 《Animal genetics》2020,51(4):568-578
Parathyroid hormone (PTH) is a crucial regulator of calcium homeostasis and bone remodeling, and the parathyroid hormone 1 receptor (PTH1R) belongs to a class II G-protein-coupled receptor. PTH activates PTH1R, which mediates catabolic and anabolic processes in the skeleton. However, the functional mechanism of PTH1R has not been thoroughly elucidated in organisms. This study identified a 51 bp indel mutation in the first intron of the PTH1R gene and elucidated the effect of this gene mutation on the growth and carcass traits in chickens. The results indicated that the 51 bp indel was significantly associated with subcutaneous fat thickness, abdominal fat weight, body weight and daily gain over 4–8 weeks. Furthermore, we found that PTH1R gene expression was highest in the kidney and liver tissues, and it showed a trend of decreasing in leg and breast muscle tissues at different embryonic stages. In addition, we examined the expression of the three genotypes of the PTH1R gene in the liver, breast muscle and abdominal fat and found that the II genotype was significantly higher than the DD and ID genotypes. In summary, these findings suggest that the PTH1R gene can serve as a potential molecular marker for chicken breeding. 相似文献
100.
Mahdi Jalili Tom Gebhardt Olaf Wolkenhauer Ali Salehzadeh-Yazdi 《生物化学与生物物理学报:疾病的分子基础》2018,1864(6):2349-2359
Decoding health and disease phenotypes is one of the fundamental objectives in biomedicine. Whereas high-throughput omics approaches are available, it is evident that any single omics approach might not be adequate to capture the complexity of phenotypes. Therefore, integrated multi-omics approaches have been used to unravel genotype–phenotype relationships such as global regulatory mechanisms and complex metabolic networks in different eukaryotic organisms. Some of the progress and challenges associated with integrated omics studies have been reviewed previously in comprehensive studies. In this work, we highlight and review the progress, challenges and advantages associated with emerging approaches, integrating gene expression and protein-protein interaction networks to unravel network-based functional features. This includes identifying disease related genes, gene prioritization, clustering protein interactions, developing the modules, extract active subnetworks and static protein complexes or dynamic/temporal protein complexes. We also discuss how these approaches contribute to our understanding of the biology of complex traits and diseases. This article is part of a Special Issue entitled: Cardiac adaptations to obesity, diabetes and insulin resistance, edited by Professors Jan F.C. Glatz, Jason R.B. Dyck and Christine Des Rosiers. 相似文献