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he aim of this study was to evaluate the effect of controlled intraoral grinding and polishing on the roughness of full-contour zirconia compared to classical veneered zirconia. Thirty bar-shaped zirconia specimens were fabricated and divided into two groups (n=15). Fifteen specimens (group 1) were glazed and 15 specimens (group 2) were veneered with feldspathic ceramic and then glazed. Prior to grinding, maximum roughness depth (Rmax) values were measured using a profilometer, 5 times per specimen. Simulated clinical grinding and polishing were performed on the specimens under water coolant for 15 s and 2 N pressure. For grinding, NTI diamonds burs with grain sizes of 20 µm, 10 µm, and 7.5 µm were used sequentially. The ground surfaces were polished using NTI kits with coarse, medium and fine polishers. After each step, Rmax values were determined. Differences between groups were examined using one-way analysis of variance (ANOVA). The roughness of group 1 was significantly lower than that of group 2. The roughness increased significantly after coarse grinding in both groups. The results after glazing were similar to those obtained after fine grinding for non-veneered zirconia. However, fine-ground veneered zirconia had significantly higher roughness than venerred, glazed zirconia. No significant difference was found between fine-polished and glazed zirconia, but after the fine polishing of veneered zirconia, the roughness was significantly higher than after glazing. It can be concluded that for full-contour zirconia, fewer defects and lower roughness values resulted after grinding and polishing compared to veneered zirconia. After polishing zirconia, lower roughness values were achieved compared to glazing; more interesting was that the grinding of glazed zirconia using the NTI three-step system could deliver smooth surfaces comparable to untreated glazed zirconia surfaces.
The U-turn is a classical three-dimensional RNA folding motif first identified in the anticodon and T-loops of tRNAs. It also occurs frequently as a building block in other functional RNA structures in many different sequence and structural contexts. U-turns induce sharp changes in the direction of the RNA backbone and often conform to the 3-nt consensus sequence 5'-UNR-3' (N = any nucleotide, R = purine). The canonical U-turn motif is stabilized by a hydrogen bond between the N3 imino group of the U residue and the 3' phosphate group of the R residue as well as a hydrogen bond between the 2'-hydroxyl group of the uridine and the N7 nitrogen of the R residue. Here, we demonstrate that a protonated cytidine can functionally and structurally replace the uridine at the first position of the canonical U-turn motif in the apical loop of the neomycin riboswitch. Using NMR spectroscopy, we directly show that the N3 imino group of the protonated cytidine forms a hydrogen bond with the backbone phosphate 3' from the third nucleotide of the U-turn analogously to the imino group of the uridine in the canonical motif. In addition, we compare the stability of the hydrogen bonds in the mutant U-turn motif to the wild type and describe the NMR signature of the C+-phosphate interaction. Our results have implications for the prediction of RNA structural motifs and suggest simple approaches for the experimental identification of hydrogen bonds between protonated C-imino groups and the phosphate backbone.
A consistent muscle activation strategy underlies crawling and swimming in Caenorhabditis elegans
(2014)
Although undulatory swimming is observed in many organisms, the neuromuscular basis for undulatory movement patterns is not well understood. To better understand the basis for the generation of these movement patterns, we studied muscle activity in the nematode Caenorhabditis elegans. Caenorhabditis elegans exhibits a range of locomotion patterns: in low viscosity fluids the undulation has a wavelength longer than the body and propagates rapidly, while in high viscosity fluids or on agar media the undulatory waves are shorter and slower. Theoretical treatment of observed behaviour has suggested a large change in force–posture relationships at different viscosities, but analysis of bend propagation suggests that short-range proprioceptive feedback is used to control and generate body bends. How muscles could be activated in a way consistent with both these results is unclear. We therefore combined automated worm tracking with calcium imaging to determine muscle activation strategy in a variety of external substrates. Remarkably, we observed that across locomotion patterns spanning a threefold change in wavelength, peak muscle activation occurs approximately 45° (1/8th of a cycle) ahead of peak midline curvature. Although the location of peak force is predicted to vary widely, the activation pattern is consistent with required force in a model incorporating putative length- and velocity-dependence of muscle strength. Furthermore, a linear combination of local curvature and velocity can match the pattern of activation. This suggests that proprioception can enable the worm to swim effectively while working within the limitations of muscle biomechanics and neural control.
This article focuses on the opportunities and challenges of implementing an extensive reading project in an English as a foreign language classroom in Germany. Studies such as PISA have shown that comparatively poor German and foreign language reading skills are still a prevalent issue in German society today. Consequently, the question of how these poor results can be improved is of utmost importance. Reading motivation is often described as the ‘driving force of reading’. Research has shown that if reading motivation and reading for pleasure are supported, interest in reading in a foreign language can be created, which may in turn have a positive impact on the other influential factors in reading and related skills. Dörnyei’s framework of L2 motivation sums up the current thinking on reading motivation. With its constituents ‘language’, ‘learner’, and ‘learning situation’, it shows the aspects to be taken into consideration when it comes to the improvement of motivation. Within this theoretical framework, an ER project was conducted at a grammar school (Gymnasium) in Frankfurt/Main, Germany. On the basis of the gathered data, gained from questionnaires, worksheets and the transcript of a focus group discussion, six main categories could be identified. They point to the development of a positive attitude towards reading among the students and the potential of graphic novels as a motivating factor. It was also confirmed that a successful application of reading strategies led to increased motivation. Generally, the project showed that reading is still an issue amongst many teenagers and that an ER project can affect learners, their motivation and related language skills in a positive way.
Aim: The cytokine receptor tumor necrosis factor receptor superfamily member 9 (TNFRSF9) is mainly considered to be a co-stimulatory activation marker in hematopoietic cells. Several preclinical models have shown a dramatic beneficial effect of treatment approaches targeting TNFRSF9 with agonistic antibodies. However, preliminary clinical phase I/II studies were stopped after the occurrence of several severe deleterious side effects. In a previous study, it was demonstrated that TNFRSF9 was strongly expressed by reactive astrocytes in primary central nervous system (CNS) tumors, but was largely absent from tumor or inflammatory cells. The aim of the present study was to address the cellular source of TNFRSF9 expression in the setting of human melanoma brain metastasis, a highly immunogenic tumor with a prominent tropism to the CNS.
Methods: Melanoma brain metastasis was analyzed in a cohort of 78 patients by immunohistochemistry for TNFRSF9 and its expression was correlated with clinicopathological parameters including sex, age, survival, tumor size, number of tumor spots, and BRAF V600E expression status.
Results: Tumor necrosis factor receptor superfamily member 9 was frequently expressed independently on both melanoma and endothelial cells. In addition, TNFRSF9 was also present on smooth muscle cells of larger vessels and on a subset of lymphomonocytic tumor infiltrates. No association between TNFRSF9 expression and patient survival or other clinicopathological parameters was seen. Of note, several cases showed a gradual increase in TNFRSF9 expression on tumor cells with increasing distance from blood vessels, an observation that might be linked to hypoxia-driven TNFRSF9 expression in tumor cells.
Conclusion: The findings indicate that the cellular source of TNFRSF9 in melanoma brain metastasis largely exceeds the lymphomonocytic pool, and therefore further careful (re-) assessment of potential TNFRSF9 functions in cell types other than hematopoietic cells is needed. Furthermore, the hypothesis of hypoxia-driven TNFRSF9 expression in brain metastasis melanoma cells requires further functional testing.
Speolepta leptogaster (Winnertz, 1863) is frequently occurring in European subterranean environments. As for most cave animals, studies addressing non-anatomical aspects are sparse. Here we present the first molecular study on S. leptogaster. We investigated the demographic structure (i.e. COI locus) of 69 specimens from 36 underground populations in Hesse (Central German Uplands) to get first insights into the species’ dispersal ability.
In total, 14 haplotypes were revealed. Haplotype diversity was relatively high, whereas nucleotide diversity was low. Furthermore, a significant but low pattern of isolation-by-distance and (a) past population expansion event(s) were detected.
Our genetic results suggest a (good) active dispersal ability for Speolepta leptogaster. The occurrence of several surface records of adult specimens corroborates this hypothesis. We discuss the developmental stages of S. leptogaster in the context of the ecological classification system and regard the species as a eutroglophile. Evidence has been found to distinguish two larval types. A reconstructed life-cycle of the species is provided.
Does the rotten child spoil his companion? : spatial peer effects among children in rural India
(2014)
This paper identifies the effect of neighborhood peer groups on childhood skill acquisition using observational data. We incorporate spatial peer interaction, defined as a child's nearest geographical neighbors, into a production function of child cognitive development in Andhra Pradesh, India. Our peer group definition takes the form of networks, whose structure allows us to identify endogenous peer effects and contextual effects separately. We exploit variation over time to avoid confounding correlated with social effects. Our results suggest that spatial peer and neighborhood effects are strongly positively associated with a child's cognitive skill formation. Further, we explore the effect of peer groups in helping to provide insurance against the negative impact of idiosyncratic shocks to child learning. We find that the data reject full risk-sharing, but cannot rule out the existence of partial risk-sharing on behalf of peers. We show that peer effects are robust to different specifications of peer interactions and investigate the sensitivity of our estimates to potential misspecification of the network structure using Monte Carlo experiments.
Research in the field of Digital Humanities, also known as Humanities Computing, has seen a steady increase over the past years. Situated at the intersection of computing science and the humanities, present efforts focus on making resources such as texts, images, musical pieces and other semiotic artifacts digitally available, searchable and analysable. To this end, computational tools enabling textual search, visual analytics, data mining, statistics and natural language processing are harnessed to support the humanities researcher. The processing of large data sets with appropriate software opens up novel and fruitful approaches to questions in the traditional humanities. This report summarizes the Dagstuhl seminar 14301 on “Computational Humanities - bridging the gap between Computer Science and Digital Humanities”.
1998 ACM Subject Classification I.2.7 Natural Language Processing, J.5 Arts and Humanities
Benjamin's early reception in the United States can be broken into eight phases: 1) a few notices of his work in the 1930s; 2) the appearance of two major works, without translation, in the 'Zeitschrift für Sozialforschung', when it was published in New York and mimeographed in Los Angeles; 3) several reports of his suicide along with the death of other Jewish and left-wing writers who fell victim to Nazi terror; 4) scattered use of his work in the late 1940s and 1950s; 5) a growing realization in the early 1960s that American literary and cultural criticism was missing something of significance by neglecting Benjamin's work; 6) the appearance in the 1960s of competing portraits of Benjamin by four of his surviving friends, including Hannah Arendt, who edited and introduced the first collection of his writings in English; 7) an uncanny repetition of the earlier neglect, as a significant number of Benjamin's texts are published in Great Britain during the 1970s and early 1980s but remain unavailable in the States; 8) the beginning of a sustained critical engagement with Benjamin in the late 1970s.
At the forefront of those who tenaciously pondered this issue are, I would claim, Walter Benjamin and Ludwig Wittgenstein. Benjamin and Wittgenstein both are philosophers of language who tried to establish in unique ways the doctrine of resemblance respectively: "Lehre vom Ähnlichen" and "[Lehre der] Familienähnlichkeit." What they see and find in language are not communication and mutual understanding but instead one of the weirdest phenomena in/of the world, viz., resemblance (likeness) in/of language. This phenomenon, I would insist, indicates the correlation of appearing and disappearing, of differentiating and integrating, and of dividing and imparting of language as such. For Benjamin and Wittgenstein, to sum up, language is a paradigmatic paradoxical site of (dis)appearance, differentiating integrity, and divisive imparting. For this reason, it is worthwhile to pin down where their thoughts on language converge and where they diverge.
To explicate what distinguishes pain, Benjamin elaborates: "Of all corporeal feelings, pain alone is like a navigable river which never dries up and which leads man down to the sea. [...] Pain [...] is a link between worlds. This is why organic pleasure is intermittent, whereas pain can be permanent. This comparison of pleasure and pain explains why the cause of pain is irrelevant for the understanding of man's nature, whereas the source of his greatest pleasure is extremely important. For every pain, even the most trivial one, can lead upward to the highest religious suffering, whereas pleasure is not capable of any enhancement, and owes any nobility it possesses to the grace of its birth - that is to say, its source. (SW I, 397)" In these important lines, pain's unique strength is linked not to its origin (this is reserved for pleasure), but rather to the way that its strenuous flow throughout the suffering body has the power to lead it to infinite heights. In contrast to pleasure, which is forever seeking out its sources, pain manifests itself most consummately when it is intensified; it fulfills itself most deeply by gradually reenforcing its own fortitude. To make sense of pain, therefore, we must understand the nature of its 'movement': and in Benjamin's metaphor of the "navigable river" - its flow. In what follows, I develop Benjamin's idea of the nature of pain as manifested in the internal law of its ,ow in two other of Benjamin's texts: 'Berlin Childhood Around 1900' (1934) and 'Thought Figures' (1933).
One of the cruxes of Walter Benjamin’s work is the tension between an indebting and an expiating "memoria", i. e. the afflicting and the salvific insistence of history within the present moment. On the one hand, memory inscribes itself onto spaces and bodies in the violent and painful fashion of Kafka's "Penal Colony" apparatus. On the other hand, it can, in the form of rememoration ('Eingedenken'), sublate these very inscriptions. This sublation usually involves some form of redemptive, timely (re-)verbalization, but Benjamin’s conception of it varies. To gain a better insight into this inherent, varying tension, the article will take a closer look at the connection between pain, memory and law-positing violence in some Benjaminian texts, occasionally relating them to the historical background of his discussion.
Walter Benjamin had a revealing fascination with the legend of a Chinese artist who entered his painting and disappeared in it. In his writings this character becomes an emblematic figure that enables the philosopher to discuss the nature of representation in its various infections (in games and in painting, in theater and in cinema); to explore the status of the image and of the threshold that simultaneously separates and connects image and reality; to analyse the different bodily (i. e. "aesthetic") attitudes of the beholder in his/her close or distant relationship to the image; to investigate the manifold implications of empathy ('Einfühlung ') toward the figurative world; and finally, to approach a peculiar kind of dialectics, namely the "Chinese". My paper aims at considering such varied aspects in Benjamin's interpretation of the Chinese painter, understanding it as a true "dialectical image" that in its 'non-coincidentia oppositorum' provokes not only significant hermeneutic oscillations, but even a radical inversion of its fundamental meaning.
If we take Benjamin's definitions to their logical conclusion, then the monad and the reproduced copy are set unequivocally into binary opposition, as we, the masses capable and most needful of action, are implicitly denied the potential for liberation through aesthetic experience. This denial could not have been his long-term intention. When we take into account the breadth of his writings in response to Fascism, and we look at the artistic movements, Dada in particular, that Benjamin defines as 'politicizing art,' it seems as though we risk too narrow a reading of Benjamin's theories by assuming the aura can be, or must be, done away with. Rather, I would argue that this moment of auratic interaction is crucial to effectively politicizing art at all. Mechanically-produced art, in order to function politically, must allow its audience the space necessary to step back, awaken their 'Geistesgegenwart', and take action 'before' the present moment is finished and past. The elimination of aura - as per Benjamin’s own definitions of aura - neuters the interaction this awakening requires. While Benjamin provides the framework and asks the right questions, when determining what will allow his definitions to realize their aims most fully, I submit that he draws his line in the wrong place.
The flourishing of literature and thought during the age of Goethe may have inspired German nationalism in the 1930s, but Walter Benjamin identified other values in the period worth defending. 'Deutsche Menschen' is a short collection of edited letters by well-known German authors which Benjamin published in 1936 under the pseudonym Detlef Holz in order to hide his Jewish identity. In his inscription to Scholem's copy of the book, Benjamin wrote, "May you, Gerhard, find a chamber in this ark - which I built when the Fascist flood started to rise - for the memories of your youth," and in his sister’s copy Benjamin wrote, "This ark, built after a Jewish model, for Dora - From Walter." This essay considers what Benjamin may have meant by those inscriptions. Looking beyond discussions of "German," "Jewish," and even "German-Jewish" identity, this essay explores Benjamin's descriptions of his letter collection, asking how he conceptualized and framed it at first and how it may have changed between 1931 and 1936. The categories of tradition and agency will be my focus, which I will develop in the context of Benjamin's other writings and his particular interests in quotation and materialism. &e formation and reception of 'Deutsche Menschen' reveal a complex, ambitious project that combines many of Benjamin's ideas and goals.
Two alternative hypotheses – referred to as opportunity- and stigma-based behavior – suggest that the magnitude of the link between unemployment and crime also depends on preexisting local crime levels. In order to analyze conjectured nonlinearities between both variables, we use quantile regressions applied to German district panel data. While both conventional OLS and quantile regressions confirm the positive link between unemployment and crime for property crimes, results for assault differ with respect to the method of estimation. Whereas conventional mean regressions do not show any significant effect (which would confirm the usual result found for violent crimes in the literature), quantile regression reveals that size and importance of the relationship are conditional on the crime rate. The partial effect is significantly positive for moderately low and median quantiles of local assault rates.
Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.
Heterogenous subtypes of breast cancer need to be analyzed separately. Pooling of datasets can provide reasonable sample sizes but dataset bias is an important concern. We assembled a combined dataset of 579 Affymetrix microarrays from triple negative breast cancer (TNBC) in Gene Expression Omnibus (GEO) series GSE31519. We developed a method for selecting comparable datasets and to control for the amount of dataset bias of individual probesets.
"I Am a Hottentot" : africanist mimicry and green xenophilia in Hans Paasche and Karen Blixen
(2014)
Claims that industrialized western countries must reform their environmental practices have often been made with reference to less-developed non-western societies living in greater "harmony" or "balance" with the natural world. Examples of what I call green xenophilia (from the Greek "xenos", meaning strange, unknown or foreign, and "philia", meaning love or attraction), are myriad, wide-ranging and culturally dispersed. They range from the appearance of the iconic "crying Indian" in anti-pollution TV and newspaper spots in the months leading up to the first Earth Day on April 22 1970 to numerous environmentalist individuals' and groups' use of the fabricated "Chief Seattle's Speech" as an authoritative touchstone of ecological consciousness, and from the British Schumacher College's endorsement of India as a source of simplicity, holism, humility, vegetarianism etc. to leading deep ecologists' advocacy of East Asian religions (especially Buddhism, Jainism and Taoism) as "biocentric" alternatives to "anthropocentric" Christianity (Rolston 1987; Dunaway 2008; Krupat 2011; Corrywright 2010). Invocations of non-western cultures, identities and worldviews have proved potent heuristic devices, enabling greens both to critique the status quo and to gesture (however schematically) towards the possibility of alternatives. Pervasive media-borne ideas and images like "the Green Tibet" (Huber 1997) and "the ecological Indian" (Krech 1999) have given environmentalist ideas about the good life physical incarnation, making them seem less remote and abstract. Yet the prevalence of xenophile dis course has also made environmentalism vulnerable to recurrent accusations of romantic primitivism, orientalism and exoticism, as western greens have sometimes (though not always) appeared to buttress traditional socio-cultural norms in the very act of challenging them (Guha 1989; Lohmann 1993; Bartholomeusz 1998). What is gained and what is risked when western greens speak about, with, for or as "the other"? In this essay I engage with two early-twentieth-century North European writers, the German Hans Paasche (1881-1921) and the Dane Karen Blixen (1885-1962), whose works bring this question to the forefront. Critical of European industrialization, and awkwardly positioned vis-a-vis their upper-class social milieus, Paasche and Blixen wrote as self-made "Africans", testing the limits between colonialism, anti-colonialism and emergent forms of environmentalism and green" lifestyle reform. More precisely, Paasche in "Die Forschungsreise des Afrikaners Lukanga Kukara ins Innerste Deutschland" ("The African Lukanga Mukara's Research Joumey into the Innermost of Germany" (1912-1913) and Blixen in "Out of Africa" (1937) deploy the ambiguous form of mimicry that Susan Gubar labels "racechange", impersonating or appropriating culturally other voices and perspectives on animals, food, physical embodiment and human-natural relations (Gubar 1997). Paasche and Blixen, I argue, used their considerable intercultural insight to construct images of Africa that they hoped would stand in redemptive contrast to the humanly and environmentally ruinous beliefs and practices of European modernity. I am interested in the acts of ethnic and textual self-alienation that these writers perform because they highlight the discursive, ethical and political ambiguities of green xenophilia - ambiguities that can be explored from different positions within the developing field of ecocritical studies.
The present article analyzes a prominent yet relatively understudied contact space among Native American, New Zealand Maori, and aboriginal Taiwanese literatures: the struggle of indigenous peoples to negotiate optimal relationships between themselves and the natural world, particularly in light of capitalist modernity and globalization. Many indigenous narratives draw sharp distinctions between native peoples and outsiders, predictably portraying the former as protectors and the latter as destroyers of both nature and indigenous local cultures. The Native American Chickasaw writer Linda Hogan's (1947-) novel 'People of the Whale' (2008), the Maori writer Patricia Grace's (1937-) novel 'Patiki' (1986), and the aboriginal Taiwanese writer Topas Tamapima's short story "Zuihou de lieren" are no exception. But these texts also problematize notions of the so-called "ecological native." They do so most conspicuously by revealing the ambiguous relationships those peoples believed closest to nature have with the nonhuman world, that is to say their environmental ambiguity ('ecoambiguity') (Thornber 2012).