Totalitarianism and geography: L.S. Berg and the defence of an academic discipline in the age of Stalin

In considering the complex relationship between science and politics, the article focuses upon the career of the eminent Russian scholar, Lev Semenovich Berg (1876–1950), one of the leading geographers of the Stalin period. Already before the Russian Revolution, Berg had developed a naturalistic notion of landscape geography which later appeared to contradict some aspects of Marxist–Leninist ideology. Based partly upon Berg's personal archive, the article discusses the effects of the 1917 revolution, the radical changes which Stalin's cultural revolution (from the late 1920s) brought upon Soviet science, and the attacks made upon Berg and his concept of landscape geography thereafter. The ways in which Berg managed to defend his notion of geography (sometimes in surprisingly bold ways) are considered. It is argued that geography's position under Stalin was different from that of certain other disciplines in that its ideological disputes may have been regarded as of little significance by the party leaders, certainly by comparison with its practical importance, thus providing a degree of ‘freedom’ for some geographers at least analogous to that which has been described by Weiner (1999. A little corner of freedom: Russian nature protection from Stalin to Gorbachev. Berkeley: University of California Press) for conservationists. It is concluded that Berg and others successfully upheld a concept of scientific integrity and limited autonomy even under Stalinism, and that, in an era of ‘Big Science’, no modernizing state could or can afford to emasculate these things entirely

Global trends in aquatic animal tracking with acoustic telemetry

Acoustic telemetry (AT) is a rapidly evolving technique used to track the movements of aquatic animals. As the capacity of AT research expands it is important to optimize its relevance to management while still pursuing key ecological questions. A global review of AT literature revealed region-specific research priorities underscoring the breadth of how AT is applied, but collectively demonstrated a lack of management-driven objectives, particularly relating to fisheries, climate change, and protection of species. In addition to the need for more research with direct pertinence to management, AT research should prioritize ongoing efforts to create collaborative opportunities, establish long-term and ecosystem-based monitoring, and utilize technological advancements to bolster aquatic policy and ecological understanding worldwide

Landscape science: a Russian geographical tradition

The Russian geographical tradition of landscape science (landshaftovedenie) is analyzed with particular reference to its initiator, Lev Semenovich Berg (1876-1950). The differences between prevailing Russian and Western concepts of landscape in geography are discussed, and their common origins in German geographical thought in the late nineteenth and early twentieth centuries are delineated. It is argued that the principal differences are accounted for by a number of factors, of which Russia's own distinctive tradition in environmental science deriving from the work of V. V. Dokuchaev (1846-1903), the activities of certain key individuals (such as Berg and C. O. Sauer), and the very different social and political circumstances in different parts of the world appear to be the most significant. At the same time it is noted that neither in Russia nor in the West have geographers succeeded in specifying an agreed and unproblematic understanding of landscape, or more broadly in promoting a common geographical conception of human-environment relationships. In light of such uncertainties, the latter part of the article argues for closer international links between the variant landscape traditions in geography as an important contribution to the quest for sustainability

Uncovering key transcriptional and epigenetic changes underpinning the emergence of the glioma stem cell state

Glioblastoma Multiforme (GBM) is the most aggressive and common adult primary brain tumour, with an awful prognosis of 14 months median survival. GBMs can also occur in children, as paediatric high-grade glioma (pHGG), or diffuse intrinsic pontine glioma (DIPG), and like adult GBMs are incurable. GBM tumour growth and relapse after therapy is thought to be driven by the glioma stem cell (GSC). GSCs display similarities to neural stem and progenitor cells and likely arise from these cells. However, we currently have a poor understanding of the transcriptional and epigenetic reconfiguration which follows neural stem cell (NSC) to GSC transformation. In particular, further work is required to understand how common driver mutations contribute to immune evasion in adult GBM, and how the common paediatric mutation H3.3-G34R drives pHGG oncogenesis in a forebrain specific context. In the first instance using a novel set of engineered mouse NSC lines harbouring common adult glioma-associated driver mutations (RTK/PI3K/MAPK/P53 pathways) and transcriptional and epigenetic profiling, we explored mechanisms of adult GBM immune evasion as tumour-initiating GSCs were serially transplanted into C57BL/6J (BL6) immunocompetent mice. Second, to model the paediatric disease, an additional set of cortex and hindbrain human foetal NSC lines were engineered with paediatric glioma-associated mutations (H3.3-G34R mutations and RTK/P53 pathways). We used multi-omics data and bioinformatics approaches to characterise these adult and paediatric models of GBM, alongside adult and paediatric GSCs, to understand the transcriptional and epigenetic alterations imposed by these driver mutations. We found that triple mutants (Nf1 and Pten knock-out (KO); EGFRvIII overexpression), herein termed NPE cells, demonstrated unconstrained proliferation and a differentiation block through transcriptional downregulation and epigenetic silencing of Bmpr1b. Furthermore, we found an acquired capacity for immune evasion in NPE derivatives (in the absence of any genetic selection), suggesting a form of epigenetic immunoediting. In particular we found, upregulation of myeloid associated transcription factors (e.g. Irf8), interferon (IFN) response genes, and myeloid suppressor cell chemo-attractants such as Ccl9 which drove a myeloid-derived suppressive cell (MDSC) weighted tumour micro-environment. In human we demonstrated that GSCs could be defined by a single axis of IFN-gamma, immune response gene activation, associated with the ‘mesenchymal’ (MES) transcriptional subtype. We have therefore uncovered a key IFN driven immune evasion signal present within MES like GBM, imposed by the tumour microenvironment, which likely supports immune evasion. In a parallel analysis of foetal engineered NSC transcriptomes (H3.3-G34R, PDGFRA overexpression, and TP53 KO) obtained from cortex and hindbrain regions, we demonstrated that in a forebrain context the H3.3-G34R mutation reinforces pre-existing forebrain progenitor transcriptional circuits, whilst in the hindbrain it drives a cytostatic response. The G34R mutation does not cause widespread epigenetic changes, but instead maintains highly expressed forebrain genes through reduced binding of transcriptional regulator ZMYND11. A key mechanistic role for the oncohistone mutation H3.3-G34R in pHGG is therefore to reinforce forebrain NSC identity, explaining the mutations incompatibility within the hindbrain

Nature meets nurture: molecular genetics of gastric cancer

The immensity of genes and molecules implicated in gastric carcinogenesis is overwhelming and the relevant importance of some of these molecules is too often unclear. This review serves to bring us up-to-date with the latest findings as well as to look at the larger picture in terms of how to tackle the problem of solving this multi-piece puzzle. In this review, the environmental nurturing of intestinal cancer is discussed, beginning with epidemiology (known causative factors for inducing molecular change), an update of H. pylori research, including the role of inflammation and stem cells in premalignant lesions. The role of E-cadherin in the nature (genotype) of diffuse gastric cancer is highlighted, and finally the ever growing discipline of SNP analysis (including IL1B) is discussed

High contributions of sea ice derived carbon in polar bear (Ursus maritimus) tissue.

Polar bears (Ursus maritimus) rely upon Arctic sea ice as a physical habitat. Consequently, conservation assessments of polar bears identify the ongoing reduction in sea ice to represent a significant threat to their survival. However, the additional role of sea ice as a potential, indirect, source of energy to bears has been overlooked. Here we used the highly branched isoprenoid lipid biomarker-based index (H-Print) approach in combination with quantitative fatty acid signature analysis to show that sympagic (sea ice-associated), rather than pelagic, carbon contributions dominated the marine component of polar bear diet (72-100%; 99% CI, n = 55), irrespective of differences in diet composition. The lowest mean estimates of sympagic carbon were found in Baffin Bay bears, which were also exposed to the most rapidly increasing open water season. Therefore, our data illustrate that for future Arctic ecosystems that are likely to be characterised by reduced sea ice cover, polar bears will not only be impacted by a change in their physical habitat, but also potentially in the supply of energy to the ecosystems upon which they depend. This data represents the first quantifiable baseline that is critical for the assessment of likely ongoing changes in energy supply to Arctic predators as we move into an increasingly uncertain future for polar ecosystems

Group 4 permethylindenyl complexes for the polymerisation of L-, D- and rac-lactide monomers

A series of well-defined group 4 permethylindenyl complexes have been prepared and fully characterised by NMR spectroscopy and X-ray crystallography. Me2SB(Cp,I*)ZrCl2 ({(η5-C9Me6)Me2Si(η5-C5H4)}ZrCl2; 1), Me2SB(CpMe,I*)ZrCl2 ({(η5-C9Me6)Me2Si(η5-C5H3Me)}ZrCl2; 2), Me2SB(Cp,I*)HfCl2 (3) and Z-Me2SB(Cp,I*)ZrCl(O-2,6-Me-C6H3) (4) were investigated as initiators for the ring-opening polymerisation (ROP) of l-, d- and rac-lactide monomers in the presence of benzyl alcohol. 1-4 displayed second order dependence on monomer concentration and produced isotactic and heterotactic (Pr = 0.81) polylactides for the polymerisation of l-, d- and rac-lactide respectively. The effects of temperature, catalyst concentration, co-initiator concentration, solvent and scale were studied. At 80 °C, with two equivalents of benzyl alcohol, 4 was the most active initiator for the ROP of l-, d- and rac-lactide (kobs = 6.39, 6.38 and 5.89 M-1 h-1 respectively). The polylactides were characterised by NMR spectroscopy, GPC and MALDI-TOF mass spectrometry