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MATTI BUNZL 《American anthropologist》2004,106(3):435-442
This article proposes the possibility of a neo-Boasian anthropology conceived at the intersection of Foucauldian genealogy, Boasian historicism, and the epistemic rethinking of the discipline's Self/Other binary. Shifting from a perspective of posing the ethnographic object as Other toward a Boasian conception of the past as the principal site of inquiry, the piece thus advocates an anthropological project grounded in the history of the present. This conception, it is argued, can overcome several of the dilemmas currently facing the discipline, the awkward status of "native anthropology" foremost among them. 相似文献
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Fish predation and reduction in body size in a Cladoceran population: palaeoecological evidence 总被引:3,自引:1,他引:2
JUKKA SALO MARI WALLS MARJUT RAJASILTA JOUKO SARVALA MATTI RÄSÄNEN VELI-PEKKA SALONEN 《Freshwater Biology》1989,21(2):217-221
SUMMARY. 1 We studied the recent history (1852-1982) of Lake Pyhä-järvi, south-west Finland, using both cladoceran microfossils and independent historical data. The objective of the study was to assess the impact of introduced planktivorous whitefish Coregonus lavaretus s.1. on zooplankton, especially on the main prey species Bosmina coregoni Baird s.str.
2. A size-frequency analysis of carapace remains preserved in the sediments clearly shows a size shift in a Bosmina coregoni population. The carapace length of B. coregoni decreased by 11.0% after the introduction of the size-selective planktivorous whitefish, indicating a parallel body-size reduction.
3.During the study period no changes could be found in the carapace length of Chydorus sphaericus O. F. Müller, which was not preyed upon. 相似文献
2. A size-frequency analysis of carapace remains preserved in the sediments clearly shows a size shift in a Bosmina coregoni population. The carapace length of B. coregoni decreased by 11.0% after the introduction of the size-selective planktivorous whitefish, indicating a parallel body-size reduction.
3.During the study period no changes could be found in the carapace length of Chydorus sphaericus O. F. Müller, which was not preyed upon. 相似文献
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MATTI WAHLSTEN NATALIA BATTCHIKOVA ATEEQ UR REHMAN IMRE VASS MAARIT KARONEN JARI SINKKONEN PERTTU PERMI KAARINA SIVONEN EVA‐MARI ARO YAGUT ALLAHVERDIYEVA 《Plant, cell & environment》2014,37(6):1371-1381
Screening of 55 different cyanobacterial strains revealed that an extract from Nostoc XPORK14A drastically modifies the amplitude and kinetics of chlorophyll a fluorescence induction of Synechocystis PCC 6803 cells. After 2 d exposure to the Nostoc XPORK14A extract, Synechocystis PCC 6803 cells displayed reduced net photosynthetic activity and significantly modified electron transport properties of photosystem II under both light and dark conditions. However, the maximum oxidizable amount of P700 was not strongly affected. The extract also induced strong oxidative stress in Synechocystis PCC 6803 cells in both light and darkness. We identified the secondary metabolite of Nostoc XPORK14A causing these pronounced effects on Synechocystis cells. Mass spectrometry and nuclear magnetic resonance analyses revealed that this compound, designated as M22, has a non‐peptide structure. We propose that M22 possesses a dual‐action mechanism: firstly, by photogeneration of reactive oxygen species in the presence of light, which in turn affects the photosynthetic machinery of Synechocystis PCC 6803; and secondly, by altering the in vivo redox status of cells, possibly through inhibition of protein kinases. 相似文献
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ADAM J. VANBERGEN BEN A. WOODCOCK MATTI KOIVULA JARI NIEMELÄ D. JOHAN KOTZE TOM BOLGER VALERIE GOLDEN FLORENCE DUBS GUILLAUME BOULANGER JOSE SERRANO JOSÉ LUÍS LENCINA ARTUR SERRANO CARLOS AGUIAR ANNE‐CATHERINE GRANDCHAMP SILVIA STOFER GYÖZÖ SZÉL EVA IVITS PETRA ADLER JOCHUM MARKUS ALLAN D. WATT 《Ecological Entomology》2010,35(2):226-235
1. Anthropogenic pressures have produced heterogeneous landscapes expected to influence diversity differently across trophic levels and spatial scales. 2. We tested how activity density and species richness of carabid trophic groups responded to local habitat and landscape structure (forest percentage cover and habitat richness) in 48 landscape parcels (1 km2) across eight European countries. 3. Local habitat affected activity density, but not species richness, of both trophic groups. Activity densities were greater in rotational cropping compared with other habitats; phytophage densities were also greater in grassland than forest habitats. 4. Controlling for country and habitat effects, we found general trophic group responses to landscape structure. Activity densities of phytophages were positively correlated, and zoophages uncorrelated, with increasing habitat richness. This differential functional group response to landscape structure was consistent across Europe, indicated by a lack of a country × habitat richness interaction. Species richness was unaffected by landscape structure. 5. Phytophage sensitivity to landscape structure may arise from relative dependency on seed from ruderal plants. This trophic adaptation, rare in Carabidae, leads to lower phytophage numbers, increasing vulnerability to demographic and stochastic processes that the greater abundance, species richness, and broader diet of the zoophage group may insure against. 相似文献
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HANNE Salmenkari ANITA LAITINEN RICHARD A. FORSGÅRD MERVI HOLAPPA JERE LINDÉN LAURI PASANEN MATTI KORHONEN RIITTA KORPELA JOHANNA NYSTEDT 《Cytotherapy》2019,21(2):175-188
Background
Mesenchymal stromal cells (MSCs) are a promising candidate for treatment of inflammatory disorders, but their efficacy in human inflammatory bowel diseases (IBDs) has been inconsistent. Comparing the results from various pre-clinical and clinical IBD studies is also challenging due to a large variation in study designs.Methods
In this comparative pre-clinical study, we compared two administration routes and investigated the safety and feasibility of both fresh and cryopreserved platelet-lysate–expanded human bone marrow–derived MSCs without additional licensing in a dextran sodium sulfate (DSS) colitis mouse model both in the acute and regenerative phases of colitis. Body weight, macroscopic score for inflammation and colonic interleukin (IL)-1β and tumor necrosis factor (TNF)α concentrations were determined in both phases of colitis. Additionally, histopathology was assessed and Il-1β and Agtr1a messenger RNA (mRNA) levels and angiotensin-converting enzyme (ACE) protein levels were measured in the colon in the regenerative phase of colitis.Results
Intravenously administered MSCs exhibited modest anti-inflammatory capacity in the acute phase of colitis by reducing IL-1β protein levels in the inflamed colon. There were no clear improvements in mice treated with fresh or cryopreserved unlicensed MSCs according to weight monitoring results, histopathology and macroscopic score results. Pro-inflammatory ACE protein expression and shedding were reduced by cryopreserved MSCs in the colon.Conclusions
In conclusion, we observed a good safety profile for bone marrow–derived platelet lysate–expanded MSCs in a mouse pre-clinical colitis model, but the therapeutic effect of MSCs prepared without additional licensing (i.e. such as MSCs are administered in graft-versus-host disease) was modest in the chosen in vivo model system and limited to biochemical improvements in cytokines without a clear benefit in histopathology or body weight development. 相似文献7.
MATTI JANHUNEN GEIR RUDOLFSEN JUKKA KEKÄLÄINEN LARS FIGENSCHOU NINA PEUHKURI RAINE KORTET 《Biological journal of the Linnean Society. Linnean Society of London》2009,98(4):794-802
The modern theories of sexual selection predict that male sexual ornaments may have evolved as reliable signals of male fertilization efficiency. However, among the studies of fishes with external fertilization, the results have yielded ambiguous evidence. In the present study, we present data on the phenotypic relationships between red spawning coloration and ejaculate quality (spermatocrit, sperm motility) from Arctic charr, Salvelinus alpinus. We studied two generations (F1 and F2) of males from a large lake population, reared in a standardized hatchery environment, to determine whether differential hatchery history, or duration of hatchery selection, affected the variation in ejaculate characteristics or abdominal coloration. After controlling for body length, there was no difference between the hatchery generations in these traits. However, the degree of redness increased with fish size. We found a positive correlation between sperm velocity and sperm longevity, indicating a functional integration between these sperm features across generations. Sperm velocity was also positively correlated with male redness. Therefore, the finding obtained in the present study suggests that the carotenoid‐based ornamentation in Arctic charr may provide information about differences between males in their fertilization potential. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98 , 794–802. 相似文献
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MATTI JANHUNEN JUKKA KEKÄLÄINEN RAINE KORTET PEKKA HYVÄRINEN JORMA PIIRONEN 《Biological journal of the Linnean Society. Linnean Society of London》2011,103(3):602-611
Female mate choice is considered an important evolutionary agent, but there has been an ongoing debate over the fitness consequences it produces, especially in species that have a resource‐free mating system. We examined a potential fitness benefit resulting from the pre‐spawning mate preference in Arctic charr Salvelinus alpinus, a salmonid fish with no parental care. The females were first allowed to discriminate behaviourally between two males presented to them in a free choice test. We then tested with controlled fertilizations whether the females would accrue indirect genetic benefits for their offspring, as measured by embryonic viability, if they had mated with the male they preferred. Both parental identities influenced offspring survivorship, but the females did not consistently prefer the male which gave her the higher reproductive success. Neither was the degree of male red breeding coloration associated with female preference or the observable genetic quality. In contrast, there was a negative relationship between female coloration and her offspring survivorship, suggesting a significant trade‐off in resource investment between sexual ornamentation and reproduction. To conclude, the potential indirect fitness consequences arising from females' pre‐spawning mate preference seem to be negligible in early stages of development of Arctic charr. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 602–611. 相似文献
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IRA BASHKOW MATTI BUNZL RICHARD HANDLER REW ORTA DANIEL ROSENBLATT 《American anthropologist》2004,106(3):433-434