Climate change and rising oil prices have thrust the Arctic to the top of the foreign policy agenda and raised difficult issues of sovereignty, security and environmental protection. Improved access ...for shipping and resource development is leading to new international rules on safety, pollution prevention and emergency response. Around the Arctic, maritime boundary disputes are being negotiated and resolved, and new international institutions, such as the Arctic Council, are mediating deep-rooted tensions between Russia and NATO and between nation states and indigenous peoples. International Law and the Arctic explains these developments and reveals a strong trend towards international cooperation and law-making. It thus contradicts the widespread misconception that the Arctic is an unregulated zone of potential conflict.
To understand better how selection processes balance the benefits of Ig repertoire diversity with the risks of autoreactivity and nonfunctionality of highly variable IgH CDR3s, we collected millions ...of rearranged germline IgH CDR3 sequences by deep sequencing of DNA from mature human naive B cells purified from four individuals and analyzed the data with computational methods. Long HCDR3 regions, often components of HIV-neutralizing Abs, appear to derive not only from incorporation of long D genes and insertion of large N regions but also by usage of multiple D gene segments in tandem. However, comparison of productive and out-of-frame IgH rearrangements revealed a selection bias against long HCDR3 loops, suggesting these may be disproportionately either poorly functional or autoreactive. Our data suggest that developmental selection removes HCDR3 loops containing patches of hydrophobicity, which are commonly found in some auto-antibodies, and at least 69% of the initial productive IgH rearrangements are removed from the repertoire during B cell development. Additionally, we have demonstrated the potential utility of this new technology for vaccine development with the identification in all four individuals of related candidate germline IgH precursors of the HIV-neutralizing Ab 4E10.
The first book to address the vast diversity of Northern circumpolar cinemas from a transnational perspective, Films on Ice: Cinemas of the Arctic presents the region as one of great and previously ...overlooked cinematic diversity. With chapters on polar explorer films, silent cinema, documentaries, ethnographic and indigenous film, gender and ecology, as well as Hollywood and the USSR’s uses and abuses of the Arctic, this book provides a groundbreaking account of Arctic cinemas from 1898 to the present. Challenging dominant notions of the region in popular and political culture, it demonstrates how moving images (cinema, television, video, and digital media) have been central to the very definition of the Arctic since the end of the nineteenth century. Bringing together an international array of European, Russian, Nordic, and North American scholars, Films on Ice radically alters stereotypical views of the Arctic region, and therefore of film history itself.‘Gathering leading scholars across the three continents meeting in the Arctic, MacKenzie and Stenport open up the utopian, dystopian and heterotopian dimensions of Arctic film, a shimmering, crystalline view not only on the contest over the meanings of polar space, but onto the possibilities for reconceptualising world cinema.’ - Sean Cubitt, Professor of Film and Television, Goldsmiths, University of London"
The Changing Arctic and the European Union a book based on the report "Strategic Assessment of the Development of the Arctic: Assessment Conducted for the European Union". It provides a balanced ...overview of changes taking place in the Arctic. The ways how the EU affects Arctic developments is considered, including the process of formulating an umbrella EU Arctic policy.
China’s Arctic Ambitions and What They Mean for Canada is one of the first in-depth studies of China’s increasing interest in the Arctic. It offers a holistic approach to understanding Chinese ...motivations and the potential impacts of greater Chinese presence in the circumpolar region, exploring resource development, shipping, scientific research, governance, and security. Drawing on extensive research in Chinese government documentation, business and media reports, and current academic literature, this timely volume eschews the traditional assumption that Chinese actions are unified and monolithic in their approach to Arctic affairs. Instead, it offers a careful analysis of the different, and often competing, interests and priorities of Chinese government and industry. Analyzing Chinese interests and activities from a Canadian perspective, the book provides an unparalleled point of reference to discuss the implications for the Canadian and broader circumpolar North.
Stellar feedback is needed to produce realistic giant molecular clouds and galaxies in simulations, but due to limited numerical resolution, feedback must be implemented using sub-grid models. ...Observational work is an important means to test and anchor these models, but limited studies have assessed the relative dynamical role of multiple feedback modes, particularly at the earliest stages of expansion when H ii regions are still deeply embedded. In this paper, we use multiwavelength (radio, infrared, and X-ray) data to measure the pressures associated with direct radiation (Pdir), dust-processed radiation (PIR), photoionization heating (PH II), and shock-heating from stellar winds (PX) in a sample of 106 young, resolved H ii regions with radii 0.5 pc to determine how stellar feedback drives their expansion. We find that the PIR dominates in 84% of the regions and that the median Pdir and PH II are smaller than the median PIR by factors of 6 and 9, respectively. Based on the radial dependences of the pressure terms, we show that H ii regions transition from PIR-dominated to PH II-dominated at radii of ∼3 pc. We find a median trapping factor of ftrap ∼ 8 without any radial dependence for the sample, suggesting this value can be adopted in sub-grid feedback models. Moreover, we show that the total pressure is greater than the gravitational pressure in the majority of our sample, indicating that the feedback is sufficient to expel gas from the regions.
In this timely new book, international scholars and military professionals come together to explore the strategic consequences of the thawing of the Arctic. Their analyses of efforts by governments ...and defence, security, and coast guard organizations to address these challenges make timely and urgent reading. Rather than a single national perspective, The Fast-Changing Arctic brings together circumpolar viewpoints from North America, Europe and Asia for an integrated discussion of strategic military, diplomatic, and security challenges in the high North. Thoughtful analyses are included of different regions, climate issues, institutions, and foreign and security policies. This is an important book for students of international studies, political science, and northern studies. With a Foreword by the Honorable Mead Treadwell and an Afterword by Lawson W. Brigham. With Contributions By: Alun Anderson, Caitlyn Antrim, Rasmus Gjedsso Bertelsen, Lawson W. Brigham, Ian G. Brosnan, Daniel Clausen, J.G. Michael Clausen, Lassi Kalevi Heininen, Nong Hong, Rob Huebert, Henrik Jedig Jorgensen, P. Whitney Lackenbauer, Thomas M. Leschine, James Manicom, Edward L. Miles, Barry Scott Zellen, and Katarzyna Zysk.
Summary
Chlamydomonas reinhardtii is a unicellular green alga that has attracted interest due to its potential biotechnological applications, and as a model for algal biofuel and energy metabolism. ...Despite all the advantages that this unicellular alga offers, poor and inconsistent expression of nuclear transgenes remains an obstacle for basic and applied research. We used a data‐mining strategy to identify highly expressed genes in Chlamydomonas whose flanking sequences were tested for the ability to drive heterologous nuclear transgene expression. Candidates identified in this search included two ribosomal protein genes, RPL35a and RPL23, and ferredoxin, FDX1, whose flanking regions including promoters, terminators and untranslated sequences could drive stable luciferase transgene expression to significantly higher levels than the commonly used Hsp70A‐RBCS2 (AR) hybrid promoter/terminator sequences. The RPL23 flanking sequences were further tested using the zeocin resistance gene sh‐ble as a reporter in monocistronic and dicistronic constructs, and consistently yielded higher numbers of zeocin‐resistant transformants and higher levels of resistance than AR‐ or PSAD‐based vectors. Chlamydomonas RPL23 sequences also enabled transgene expression in Volvox carteri. Our study provides an additional benchmark for strong constitutive expression of transgenes in Chlamydomonas, and develops a general approach for identifying flanking sequences that can be used to drive transgene expression for any organism where transcriptome data are available.
Significance Statement
Chlamydomonas is a green alga used for basic research and as a reference organism for biotechnology applications. Despite its many advantages, reliable expression of nuclear transgenes remains an obstacle. We used a transcriptome‐based data mining strategy to identify flanking sequences from genes that are highly and stably expressed across the Chlamydomonas diurnal cycle. Expression of transgenes under the control of these sequences was significantly improved over the most widely used existing vectors.
•GM- CSF increases the number of white blood cells.•GM -CSF can partially restore BCR heavy chain CDR3 repertoire.•GM -CSF may lead to rearrangement, proliferation and activation of abnormal B cells.
...Leukopenia is a common manifestation of many diseases, including global outbreak SAS-CoV-2 infection. Granulocyte-macrophage colony-stimulating factor (GM -CSF) has been proved to be effective in promoting lymphocyte regeneration, but adverse immunological effects have also emerged. This study aim to investigate the effect of GM -CSF on BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration. Cyclophosphamide (CTX) and GM -CSF were used to inhibit and stimulate bone marrow hematopoiesis, respectively. High throughput sequencing was applied to detect the characteristics of BCR CDR3 repertoire in controls, CTX group and GM -CSF group. The white blood cells (WBCs) were quickly reduced (P < 0.05) with lymphocytes decreasing causing by CTX, and the WBCs and lymphocytes returned to the level of controls after GM -CSF treatment. The diversity of BCR heavy chain CDR3 repertoire was also significantly decreased in CTX group. Although there is still a big gap from the controls, the diversity was picked up after GM -CSF treatment. The expression of IGHD01-01, IGHD02-14 and IGHJ04-01 with high-frequency usage regularly and significantly changed in three groups, and many genes with low-frequency usage lost in CTX group and did not reappear in GM -CSF group. Moreover, two shared sequences and accounted for the highest proportion in GM -CSF group have been detected in animal model of chronic lymphocytic leukemia. These results revealed that GM -CSF can partially restore changes in the BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration, but it may also lead to rearrangement, proliferation and activation of abnormal B cells, which can provide a basis for further study on the adverse immunological effects and mechanism of GM -CSF treatment.
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