32 research outputs found
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
Differentiation of brain metastases from small and non-small lung cancers using apparent diffusion coefficient (ADC) maps
Background!#!Brain metastases are particularly common in patients with small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), with NSCLC showing a less aggressive clinical course and lower chemo- and radio sensitivity compared to SCLC. Early adequate therapy is highly desirable and depends on a reliable classification of tumor type. The apparent diffusion coefficient is a noninvasive neuroimaging marker with the potential to differentiate between major histological subtypes. Here we determine the sensitivity and specificity of the apparent diffusion coefficient to distinguish between NSCLC and SCLC.!##!Methods!#!We enrolled all NSCLC and SCLC patients diagnosed between 2008 and 2019 at the University Medical Center Göttingen. Cranial MR scans were visually inspected for brain metastases and the ratio of the apparent diffusion coefficient (ADC) was calculated by dividing the ADC measured within the solid part of a metastasis by a reference ADC extracted from an equivalent region in unaffected tissue on the contralateral hemisphere.!##!Results!#!Out of 411 enrolled patients, we detected 129 patients (83 NSCLC, 46 SCLC) with sufficiently large brain metastases with histologically classified lung cancer and no hemorrhage. We analyzed 185 brain metastases, 84 of SCLC and 101 of NSCLC. SCLC brain metastases showed an ADC ratio of 0.68 ± 0.12 SD, and NSCLC brain metastases showed an ADC ratio of 1.47 ± 0.31 SD. Receiver operating curve statistics differentiated brain metastases of NSCLC from SCLC with an area under the curve of 0.99 and a 95% CI of 0.98 to 1, p < 0.001. Youden's J cut-point is 0.97 at a sensitivity of 0.989 and a specificity of 0.988.!##!Conclusions!#!In patients with lung cancer and brain metastases with solid tumor parts, ADC ratio enables an ad hoc differentiation of SCLC and NSCLC, easily achieved during routine neuroradiological examination. Non-invasive MR imaging enables an early-individualized management of brain metastases from lung cancer.!##!Trial registration!#!The study was registered in the German Clinical Trials Register (DRKS00023016)
The Materiality of Method: the case of the Mass Observation Archive
The Mass Observation Archive presents numerous methodological issues for social researchers. The data are idiosyncratic, difficult to analyze, and the sample design is nonsystematic. Such issues seriously challenge conventional social research protocols. This article highlights a further characteristic of the archive: its unwieldy materiality. Focusing on the sensory experiences of the archive and its particular type of data, the article shows how the experience of getting ‘dirty with data’ plays a real and dynamic part of conducting Mass Observation research. Building on these observations, and drawing on two recent projects that have used the Archive, we reflect on the extent to which these issues are genuinely methodologically problematic, and how far the materiality of method and the sensuousness of data play a part in other research sites and methodological approaches too. In doing so, we emphasize the physical and logistical practicalities involved in engaging with all kinds of data, and highlight the opportunities as well as the constraints that these pose. We draw attention to the sensuous ‘cues’ and ‘hints’ offered by the Archive's materiality, and explore different ways of responding to these and their likely implications for the type and status of outputs produced. Finally, we consider the implications of our discussion for possible future attempts to digitize the contents of the Archive
PHLDA1 expression marks the putative epithelial stem cells and contributes to intestinal tumorigenesis
Studies employing mouse models have identified crypt base and position +4 cells as strong candidates for intestinal epithelial stem cells. Equivalent cell populations are thought to exist in the human intestine; however robust and specific protein markers are lacking. Here, we show that in the human small and large intestine, PHLDA1 is expressed in discrete crypt base and some position +4 cells. In small adenomas, PHLDA1 was expressed in a subset of undifferentiated and predominantly Ki-67-negative neoplastic cells, suggesting that a basic hierarchy of differentiation is retained in early tumorigenesis. In large adenomas, carcinomas, and metastases PHLDA1 expression became widespread, with increased expression and nuclear localization at invasive margins. siRNA-mediated suppression of PHLDA1 in colon cancer cells inhibited migration and anchorage-independent growth in vitro and tumor growth in vivo. The integrins ITGA2 and ITGA6 were downregulated in response to PHLDA1 suppression, and accordingly cell adhesion to laminin and collagen was significantly reduced. We conclude that PHLDA1 is a putative epithelial stem cell marker in the human small and large intestine and contributes to migration and proliferation in colon cancer cells. ©2011 AACR