36 research outputs found
Substrate quality drives fungal necromass decay and decomposer community structure under contrasting vegetation types
1.Fungal mycelium is increasingly recognized as a central component of soil biogeochemical cycling, yet our current understanding of the ecological controls on fungal necromass decomposition is limited to single sites and vegetation types.
2.By deploying common fungal necromass substrates in a temperate oak savanna and hardwood forest in the midwestern USA, we assessed the generality of the rate at which highâ and lowâquality fungal necromass decomposes; further, we investigated how the decomposer ânecrobiomeâ varies both across and within sites under vegetation types dominated by either arbuscular or ectomycorrhizal plants.
3.The effects of necromass quality on decay rate were robust to site and vegetation type differences, with highâquality fungal necromass decomposing, on average, 2.5 times faster during the initial stages of decay. Across vegetation types, bacterial and fungal communities present on decaying necromass differed from bulk soil microbial communities and were influenced by necromass quality. Moulds, yeasts and copiotrophic bacteria consistently dominated the necrobiome of highâquality fungal substrates.
4.Synthesis. We show that regardless of differences in decay environments, highâquality fungal substrates decompose faster and support different types of decomposer microâorganisms when compared with lowâquality fungal tissues. These findings help to refine our theoretical understanding of the dominant factors affecting fast cycling components of soil organic matter and the microbial communities associated with rapid decay
Infectious Fear: The Rhetoric of Pestilence in Middle English Didactic Texts on Death
This article examines literary references to bubonic plague in a sample of late fourteenth- and fifteenth-century English texts that are didactic in tone and address the theme of death, including Geoffrey Chaucerâs âThe Pardonerâs Taleâ, John Lydgateâs âDanse Macabreâ and the anonymous The Castle of Perseverance and âA Disputation between the Body and Wormsâ. Although there have been broad surveys of bubonic plague in Middle English literature, as well as studies of isolated texts, this article is the first to examine the role of pestilence in a group of texts linked by theme and authorial intention. It contributes to current understanding of the disease in late medieval literature and culture, showing how authors utilised the idea of pestilence as a frightening cause of sudden death and as a form of rhetoric serving to encourage readers to reflect on mortality, the spiritual health of the soul and the prospect of salvation. Whereas previous research has shown that doctors, priests and writers interpreted the pestilence as a divine punishment for sin, this study demonstrates how that belief could be exploited for rhetorical purposes. The rhetoric of pestilence emerges as a powerful contemplative tool urging readers to practise self-examination, penitence and a more active, strategic approach to death
Genome-Wide Analysis of Gene Expression in Primate Taste Buds Reveals Links to Diverse Processes
Efforts to unravel the mechanisms underlying taste sensation (gustation) have largely focused on rodents. Here we present the first comprehensive characterization of gene expression in primate taste buds. Our findings reveal unique new insights into the biology of taste buds. We generated a taste bud gene expression database using laser capture microdissection (LCM) procured fungiform (FG) and circumvallate (CV) taste buds from primates. We also used LCM to collect the top and bottom portions of CV taste buds. Affymetrix genome wide arrays were used to analyze gene expression in all samples. Known taste receptors are preferentially expressed in the top portion of taste buds. Genes associated with the cell cycle and stem cells are preferentially expressed in the bottom portion of taste buds, suggesting that precursor cells are located there. Several chemokines including CXCL14 and CXCL8 are among the highest expressed genes in taste buds, indicating that immune system related processes are active in taste buds. Several genes expressed specifically in endocrine glands including growth hormone releasing hormone and its receptor are also strongly expressed in taste buds, suggesting a link between metabolism and taste. Cell type-specific expression of transcription factors and signaling molecules involved in cell fate, including KIT, reveals the taste bud as an active site of cell regeneration, differentiation, and development. IKBKAP, a gene mutated in familial dysautonomia, a disease that results in loss of taste buds, is expressed in taste cells that communicate with afferent nerve fibers via synaptic transmission. This database highlights the power of LCM coupled with transcriptional profiling to dissect the molecular composition of normal tissues, represents the most comprehensive molecular analysis of primate taste buds to date, and provides a foundation for further studies in diverse aspects of taste biology
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"In the Old Language": A Glossary of Ojibwe Words, Phrases, and Sentences in Louise Erdrichâs Novels
Slowly the language has crept into my writing, replacing a word here, a concept there, beginning to carry weight.
The constant murmur of the pines, her beloved music, now became comprehensible to her in the same way that flows of Ojibwe language first began to make senseâa word here, a word there, a few connections, then the shape of ideas.
Itâs amazing that we even have Ojibwe speakers in this century. I get very troubled when I talk about the language. I really do have such regard for it. Itâs a very deep, earthy, descriptive, gnarled language. Itâs a great language. Itâs not simple. Itâs intellectually complex, and itâs so far beyond what I could ever hope to achieve in understanding. Itâs so tied to the landscape.
My love for the language far exceeds my ability to speak it. I just keep trying.
In Love Medicine, Lulu Nanapush, who spent her formative years at a boarding school speaking only English, tells about the time Moses Pillager talked to Nanapush: âOne summer long ago, when I was a little girl, he came to Nanapush and the two sat beneath the arbor, talking only in the old language.â Much later, as a young woman, Lulu visits Moses on his cat-ridden island and sleeps with him. She wakes up beside Moses to discover that he is talking in a language that she scarcely recognizes: âI woke to find him speaking in the old language, using words that few remember, forgotten, lost to people who live in town or dress in clothesâ (LM 81)
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âThe Earth Itself Was Sobbingâ: Madness and the Environment in Novels by Leslie Marmon Silko and Louise Erdrich
One of the difficulties faced by those of us who teach Native American literature is that our students come to us forearmed with all sorts of generous stereotypes about Indians. Our students tend to think, for example, that virtually all Native Americans live close to the earth, are proud victims of white domination, and are spiritually superior to those who have colonized them. That Indians are humble people who worship a god of nature, peaceful people who love dogs and horses, reverent people who pay daily homage to their mother earth and their father sun. That Native Americans are strong and silent in the face of oppression. That they sit tall on horseback silhouetted against the setting sun. And so on. One of the things that teachers doâor let the voices of Native American writers do for themâis complicate these kinds of stereotypes.
Of course, there is usually some truth to stereotypes. The trouble with stereotypes is that people want to be able to oversimplify a complicated subject by taking what may be true for one or two or many individuals and assume that it is true for everyone in a certain group
New directions for teaching and learning
Publ. comme no 28, winter 1986 de la revue New directions for teaching and learningBibliogr. Ă la fin des textesIndex: p. 93-9