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11.
DOMINIQUE LEGROS 《American anthropologist》1977,79(1):26-41
Cultural evolutionism and historical materialism are two fundamentally divergent theories of evolution. The nonrecognition by cultural evolutionists of Marx's distinction between "social formation" and "mode of production" has led them to interpret his thesis of the determination of superstructures by economic base as "techno-economic change begets new levels of general evolution." In fact, Marx's actual thesis was aimed at explaining the interrelationships between superstructures and economy within a previously established mode of production. As a consequence, Marx's analysis of how a new mode is "given" has been consistently ignored. Marx poses the problem of the origins of capitalism, not in terms of economic determinism, much less technological fatalism, but in terms of chance and necessity. In this paper, I attempt to draw the theoretical implications of such an approach in respect to general cultural evolution . [Marxism and cultural evolutionism; mode of production; economic determinism criticized; capitalism, rise of; cultural evolution, chance in] 相似文献
12.
Protandry, the earlier adult emergence of males, is explained as either an adaptive strategy maximizing male mating opportunities at the same time as minimizing female pre‐reproductive mortality, or as an incidental by‐product of sexual dimorphism fuelled by selection for other life‐history traits. Adult emergence sequences are monitored of broods of the gregarious larval endoparasitoid Cotesia glomerata L. (Hymenoptera: Braconidae) undergoing pupal development under different temperature regimes. As a haplodiploid species with single‐locus complementary sex determination, gender in C. glomerata is determined by the genotype at one sex locus. Haploids are always male, whereas diploids are female when heterozygous but male when homozygous at the sex locus. Sibling mating promotes homozygosity and thus the production of diploid males. Diploid males are produced at the expense of females, and impose a genetic burden on individuals and populations, despite their exceptional fertility in C. glomerata. Emergence of broods is typically completed within 2 days. Irrespective of temperature, males emerge earlier and within a shorter time interval than females, and a majority of the males in a cluster emerge before the first female. The implications of an incomplete temporal segregation of the sexes on the incidence of inbreeding in C. glomerata are discussed in the light of its sex determination mechanism and its patterns of mating, host exploitation and natal dispersal. 相似文献
13.
ROMAIN Guiho KEVIN BITEAU GIULIA GRISENDI MATHIAS CHATELAIS REGIS BRION JULIEN TAURELLE SARAH RENAULT DOMINIQUE HEYMANN MASSIMO DOMINICI FRANÇOISE REDINI 《Cytotherapy》2018,20(8):1037-1045
Background
Osteosarcoma (OS) is the most frequent pediatric malignant bone tumor. OS patients have not seen any major therapeutic progress in the last 30 years, in particular in the case of metastatic disease, which requires new therapeutic strategies. The pro-apoptotic cytokine Tumor necrosis factor (TNF)–Related Apoptosis Inducing Ligand (TRAIL) can selectively kill tumor cells while sparing normal cells, making it a promising therapeutic tool in several types of cancer. However, many OS cell lines appear resistant to recombinant human (rh)TRAIL-induced apoptosis. We, therefore, hypothesized that TRAIL presentation at the membrane level of carrier cells might overcome this resistance and trigger apoptosis.Methods
To address this, human adipose mesenchymal stromal cells (MSCs) transfected in a stable manner to express membrane-bound full-length human TRAIL (mbTRAIL) were co-cultured with several human OS cell lines.Results
This induced apoptosis by cell-to-cell contact even in cell lines initially resistant to rhTRAIL. In contrast, mbTRAIL delivered by MSCs was not able to counteract tumor progression in this OS orthotopic model.Discussion
This was partly due to the fact that MSCs showed a potential to support tumor development. Moreover, the expression of mbTRAIL did not show caspase activation in adjacent tumor cells. 相似文献14.
15.
DOMINIQUE ROSILLON 《Freshwater Biology》1986,16(2):269-277
SUMMARY. 1. The life cycle of Ephemerella major Klapalek in a chalk trout stream in Belgium took 1 year. Emergence was highly synchronized with a flight period from mid-May to mid-June. Tiny nymphs occurred from June to late August.
2. The mean instantaneous growth rate was high in autumn (3.6% wet wt day−1 ), very low from November to February (0.8% wet wt day−1 ) and high until emergence (2.3% wet wt day−1 ); short day length seemed to be the major factor reducing growth rate during winter.
3. Mortality was close to zero during winter and 1.4—1.7% day−1 during other seasons. Total mortality from egg to adult was 99.6%.
4. The annual production was about 9g wet wt m−2 year−1 and the annual P/ ratio was 7.5. There was good agreement between the production values estimated by four methods. Production rate was highest in May (13 mg wet wt m−2 day−1 ) and zero in February. 相似文献
2. The mean instantaneous growth rate was high in autumn (3.6% wet wt day
3. Mortality was close to zero during winter and 1.4—1.7% day
4. The annual production was about 9g wet wt m
16.
Soil organic carbon changes in landscape units of Belgium between 1960 and 2000 with reference to 1990 总被引:6,自引:0,他引:6
SUZANNA LETTENS JOS VAN ORSHOVEN BAS VAN WESEMAEL† BART MUYS DOMINIQUE PERRIN‡ 《Global Change Biology》2005,11(12):2128-2140
The present study quantifies changes in soil organic carbon (SOC) stocks in Belgium between 1960, 1990 and 2000 for 289 spatially explicit land units with unique soil association and land‐use type, termed landscape units (LSU). The SOC stocks are derived from multiple nonstandardized sets of field measurements up to a depth of 30 cm. Approximately half of the LSU show an increase in SOC between 1960 and 2000. The significant increases occur mainly in soils of grassland LSU in northern Belgium. Significant decreases are observed on loamy cropland soils. Although the largest SOC gains are observed for LSU under forest (22 t C ha?1 for coniferous and 29 t C ha?1 for broadleaf and mixed forest in the upper 30 cm of soil), significant changes are rare because of large variability. Because the number of available measurements is very high for agricultural land, most significant changes occur under cropland and grassland, but the corresponding average SOC change is smaller than for forests (9 t C ha?1 increase for grassland and 1 t C ha?1 decrease for cropland). The 1990 data for agricultural LSU show that the SOC changes between 1960 and 2000 are not linear. Most agricultural LSU show a higher SOC stock in 1990 than in 2000, especially in northern Belgium. The observed temporal and spatial patterns can be explained by a change in manure application intensity. SOC stock changes caused by land‐use change are estimated. The SOC change over time is derived from observed differences between SOC stocks in space. Because SOC stocks are continuously influenced by a number of external factors, mainly land‐use history and current land management and climate, this approach gives only an approximate estimate whose validity is limited to these conditions. 相似文献
17.
18.
HELEEN LEYSEN ELIZABETH R. DUMONT LOES BRABANT LUC VAN HOOREBEKE DOMINIQUE ADRIAENS 《Biological journal of the Linnean Society. Linnean Society of London》2011,104(3):680-691
Seahorses and pipefishes are extremely fast suction feeders, and the fast strikes probably result in large and rapid pressure drops in the buccal cavity. These rapid drops in pressure imply heavy mechanical loading on the cranium; hence, the feeding apparatus is thought to experience high levels of stress. We used finite element analysis (FEA) to investigate where stress accumulates under strong suction pressure, and whether there is a difference in craniofacial stress distribution between long‐ and short‐snouted species. The expectation was that high stress levels would occur at the articulations and in the cartilaginous regions of the cranium, and that, given the same pressure, the skulls of long‐snouted species would exhibit lower stress levels than the skulls of short‐snouted species, as an evolutionary increase in snout length might have made these species structurally better adapted to deal with high suction pressures. The results partially support the first hypothesis: except for Dunckerocampus dactyliophorus, all models show peak stress concentrations at the articulations and cartilaginous regions. However, no simple relationship between snout length and the magnitudes of stress predicted by the FEA was found. In an attempt to explain this lack of a relationship, the methodology was evaluated by assessing the effect of hyoid position and model construction on the stress distribution. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 680–691. 相似文献
19.
BÉNÉDICTE FABRE DOMINIQUE PIOU MARIE‐LAURE DESPREZ‐LOUSTAU BENOÎT MARÇAIS 《Global Change Biology》2011,17(10):3218-3227
Sphaeropsis shoot blight, caused by Diplodia pinea and Diplodia scrobiculata, damage conifers throughout the world. In France, the first disease outbreaks were reported during the 1990s. The factors associated with the pathogen presence in stands and the relationship between pathogen and disease distributions were analysed in order to understand the Sphaeropsis emergence. Eighty‐two stands of Pinus nigra, Pinus sylvestris, Pinus pinaster and Pinus radiata were visited. Cones were collected on the ground to assess the pathogen frequency. Diplodia spp were isolated and determined by a species‐specific PCR test. The role of potential explaining factors of D. pinea prevalence on cones was analysed by logistic regression. D. pinea was the dominant species in visited stands. The main factors influencing the pathogen presence selected in the models were host species (the pathogen being less frequent on P. pinaster than on P. nigra and P. sylvestris cones), winter temperature and summer rain, which were both positively correlated with cone colonization. The climate became more favourable to D. pinea presence within the last 15 years compared with the previous 30‐year period. By contrast, future climatic changes over the next 40 years should have far less impact on the pathogen presence. 相似文献
20.