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1.
The in vivo effects of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Middle East—Asia Minor 1 (MEAM1) saliva on the induced defense of tomato plants were examined. After infiltration of MEAM1 saliva into tomato leaves, qPCR analysis indicated strong local induction of salicylic acid (SA)‐responsive genes — salicylic acid induction deficient 2 (SID2) and β‐1,3‐glucanase (BGL2)— whereas pathogenesis‐related protein‐1 (PR1) showed strong induction both locally and systemically. The jasmonic acid (JA)‐responsive genes — omega‐3 fatty acid desaturase 3 (FAD3), lipoxygenase (LOX), and proteinase inhibitor II (PI‐II) — indicated moderate induction both locally and systemically. The activities of peroxidases and catalase were also induced both locally and systemically, whereas polyphenol oxidase and lipoxygenase were either transiently induced or unchanged. When either MEAM1 or AsiaII_3 whitefly adults were given access to leaves 2 h after saliva infiltration, the number of F1 progeny on the leaves on which the infiltration took place was significantly reduced for both. In contrast, when either MEAM1 or AsiaII_3 adults were given access to leaves 1 day after infiltration, the number of AsiaII_3 progeny was significantly reduced, whereas the number of MEAM1 progeny remained the same as the control. After 2 days, there was no significant difference for the infiltrated leaves for either species. In contrast, 2 h, 1 day, and 2 days after saliva infiltration, the number of F1 MEAM1 progeny on leaves where infiltration did not take place was the same as the controls, whereas the number of AsiaII_3 progeny was significantly reduced. Furthermore, the percentage of MEAM1 adults on leaves with high PR1 and BGL2 RNAs was significantly higher than the percentage of AsiaII_3 adults. Altogether, infiltration of MEAM1 saliva caused intense local defense, as well as moderate, but more persistent systemic defense. Both the SA and JA signaling pathways were regulated by MEAM1 salivary components, and were associated with asymmetric plant defense that favored MEAM1 over AsiaII_3.  相似文献   

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3.
Disposable orbitally shaken bioreactors are a promising alternative to stirred or wave agitated systems for mammalian and plant cell cultivation, because they provide a homogeneous and well‐defined liquid distribution together with a simple and cost‐efficient design. Cultivation conditions in the surface‐aerated bioreactors are mainly affected by the size of the volumetric oxygen transfer area (a) and the volumetric power input (P∕VL) that both result from the liquid distribution during shaking. Since Computational Fluid Dynamics (CFD)—commonly applied to simulate the liquid distribution in such bioreactors—needs high computing power, this technique is poorly suited to investigate the influence of many different operating conditions in various scales. Thus, the aim of this paper is to introduce a new mathematical model for calculating the values of a and P∕VL for liquids with water‐like viscosities. The model equations were derived from the balance of centrifugal and gravitational forces exerted during shaking. A good agreement was found among calculated values for a and P∕VL, CFD simulation values and empirical results. The newly proposed model enables a time efficient way to calculate the oxygen transfer areas and power input for various shaking frequencies, filling volumes and shaking and reactor diameters. All these parameters can be calculated fast and with little computing power. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1441–1456, 2014  相似文献   

4.
This article argues that in practice, concepts of magico‐spiritual power (Javanese: kesekten; Indonesian: kesaktian) are linked with sexuality, particularly female sexuality, in some segments of contemporary Central and East Javanese Muslim society. Few scholars have turned attention to the interconnectedness of these seemingly contradictory topics. Feminist studies tend to focus on the ways in which women locate themselves within and critique Sharia‐based discursive and social orders, without considering the roles that magico‐spiritual power and associated practices play in these Islamic systems or in Islam in a more general sense. Similarly, male scholarship that considers the cultural relevance of Islam and magic rarely refers to gendered and sexual dimensions as praxis from a feminist perspective. By drawing on examples of ‘magical women’ including the Javanese spirit queen of the southern ocean Gusti Kanjeng Ratu Kidul, the historical Hindu figure Ken Dedes, and contemporary ritual sex practices at a Muslim saint's grave, we show how women, female spiritual beings and female sexuality, and sexuality in general, can be considered sources of magico‐spiritual power in Muslim Java. Our arguments conclude that in Javanese Islam, transgression of Sharia sexual norms can be both a sign and a source of magico‐spiritual power.  相似文献   

5.
The Δ‐distance maps can detect local remodeling that is difficult to accurately determine using superimpositions. Transmembrane segments (TMSs) 11 in both LacY and XylE of the major facilitator superfamily uniquely contribute the greatest amount of mobile surface area in the outward‐occluded state and undergo analogous movements. The intracellular part of TMS11 moves away from the C‐terminal domain and into the substrate cavity during the conformational change from the outward‐occluded to the inward‐occluded state. A difference was noted between LacY and XylE when they assumed the inward open state after releasing a substrate to the inside in which TMS11 of LacY moved further into the substrate release space, whereas in XylE, TMS11 slightly retracted into the C‐terminal domain. Independent movement of the N‐terminal half of TMS11 suggests that it is flexible in the middle. Repeat‐swapped homology modeling was used to discover that a loop connecting TMSs 10 and 11 in LacY probably moves during the transition between the unavailable outward‐open state and the outward‐occluded state. TMSs 11 and the other elements displaying a notable domain‐independent movement colocalize with the interdomain linker, suggesting that these elements could drive the alternating access movement between the domain halves. Preliminary evidence indicates that analogous movements occur in other members of the major facilitator superfamily. Proteins 2015; 83:735–745. © 2015 Wiley Periodicals, Inc.  相似文献   

6.
Chen SY  Liu YP  Wang W  Gao CZ  Yao YG  Lai SJ 《Biochemical genetics》2008,46(3-4):206-215
Tongjiang cattle are a local cattle population of Sichuan Province, China, numbering approximately half a million in 2005. They have long been grouped into the Bashan breed, although they have a unique breeding history and phenotypic characteristics, as well as a restricted geographic distribution. Morphologically, they can be divided into two groups based on the basic coat color (black and russet). In order to dissect the matrilineal components of Tongjiang cattle and to compare the body size traits of the two morphological groups, we measured five body size traits among 59 Tongjiang cattle samples and further sequenced the mtDNA D-loop sequence of 54 individuals. Among the 54 mtDNAs, 37 (68.5%) were Bos taurus types and 17 (31.5%) were Bos indicus types. Four known B. taurus haplogroups (T1–T4) and one B. indicus haplogroup (I1) were detected in these samples. Two body size traits differed significantly (P < 0.05) between the black group and the russet group, although the two groups possessed similar matrilineal genetic structure. This is the first report to identify all four B. taurus haplogroups in one local Chinese cattle population. Our results suggest that the contribution of different matrilineal lineages to Chinese cattle might be more complex than we originally thought.  相似文献   

7.
Although kinship is of central importance in matrilineal (nepotistic) dominance systems, various lines of evidence indicate that its role has probably been overestimated. For example, alliances among nonkin, patterned on the basis of dominance per se, contribute to the maintenance of rank and to the remarkable stability of matrilineal rank orders. But because kin and nonkin alliances exert their stabilizing effects on the rank order simultaneously, the effect of nonkin alliances per se is unknown. We tested whether nonkin alliances are sufficient to ensure the stability of matrilineal rank relations in a laboratory-housed group of Japanese macaques (Macaca fuscata). We first created a group composed of two female subgroups: (1) a subordinate subgroup of close kin known to constitute an effective revolutionary alliance and (2) a dominant subgroup composed mostly of nonkin and distant kin known to support each other against lower-ranking females. In the course of 12 consecutive experimental manipulations, we reduced progressively the relative power of the dominant subgroup by manipulating its size and age composition. The members of the dominant subgroup maintained their rank in all experimental situations except when alone. Thus, nonkin alliances remained effective up to extremely pronounced levels of power imbalance. These results suggest that the remarkable stability of matrilineal rank orders is not conditional upon the existence of nepotistic alliances and strong matrilines of close kin.  相似文献   

8.
Habitat fragmentation in urban areas has left many species isolated and vulnerable to loss of genetic variation. White-tailed deer (Odocoileus virginianus), however, thrive in urban areas. We compared genetic diversity and structure among deer in 2 urban metroparks with deer in a fenced reserve and with deer from an open, continuously distributed population to inform urban deer management. If urban deer maintain species' typical matrilineal genetic structure, removal of female groups may effectively reduce local abundance. However, if gene flow in urban areas is high, dispersal may impede efforts to reduce abundance. Although genetic diversity was high and mean relatedness was near zero in all locations, distributions of pairwise relatedness in urban metroparks and the fenced reserve contained greater proportions of closely and distantly related deer than the open locations, likely attributable to matrilineal structure. In addition, deer from the metroparks (approx. 65 km apart) were moderately differentiated (Fst = 0.092) indicating gene flow in urban areas may be less than in other landscapes. Our results indicate that removal of matrilineal groups may reduce local urban deer abundance without inducing immigration from surrounding areas. © The Wildlife Society, 2012  相似文献   

9.
The mechanism underlying olfactory predator identification may be relatively experience‐independent, or it may rely on specific experience with predators. A mechanism by which prey might identify novel predators relies on the inevitable creation of sulfurous metabolites that are then excreted in the urine of carnivorous mammals. We tested whether free‐living, yellow‐bellied marmots (Marmota flaviventris) and mid‐sized herbivores that fall prey to a variety of carnivorous mammals could discriminate herbivore (elk—Cervus elephas) urine from predator (red fox—Vulpes vulpes, coyote—Canis latrans, mountain lion—Felis concolor, wolf—Canis lupus) urine, a novel herbivore (moose—Alces alces), and a distilled water control. We further asked how specific this assessment was by testing whether marmots responded differently to predators representing different levels of risk and to familiar vs. unfamiliar predators. We found that marmots responded more to urine from coyotes (a familiar predator on adults), mountain lions (a potentially unfamiliar predator that could kill adults) and wolves (a locally extinct predator that could kill adults) than to elk urine (a non‐predator). Red fox (a predator that poses a risk only to recently emerged marmot pups) urine elicited a less substantial (but not significantly so) response than coyote urine. Marmots can identify predators, even novel ones, using olfactory cues, suggesting that experience with a specific predator is not required to identify potential threats.  相似文献   

10.
《Plains anthropologist》2013,58(64):129-133
Abstract

The Dakota belief in wakunza or “supernatural retribution” is examined as an aspect of contemporary Sioux religion. Belief in this power is reported to be a significant mechanism in the maintenance of social control within Sioux communities on and off the reservation by insuring the chastisement of social deviants. Animistic spirits rather than individuals are attributed with possessing the power to administer justice and reprimand those committing transgressions of the Dakota moral order. Two alternative hypotheses regarding the uses of wakunza are proposed.  相似文献   

11.
This paper discusses property‐related issues and concepts among the Guajiro—a matrilineal cattle pastoralist society in Colombia and Venezuela—from a women‐oriented perspective, focusing on types of, acquisition and management of property as well as death‐ and compensation‐linked property transactions. Also considered are questions pertaining to female productivity in pastoral societies and women's significance as resources and potential property.  相似文献   

12.
Local adaptation is a key process for the maintenance of genetic diversity and population diversification. A better understanding of the mechanisms that allow (or prevent) local adaptation constitutes a key in apprehending how and at what spatial scale it occurs. The production of resting stages is found in many taxa and reflects an adaptation to outlast adverse environmental conditions. Daphnia magna (Crustacea) can alternate between asexual and sexual reproduction, the latter being linked to dormancy, as resting stages can only be produced sexually. In this species, on a continental scale, resting‐stage production is locally adapted—that is, it is induced when the photoperiod indicates the imminence of habitat deterioration. Here, we aimed to explore whether selection is strong enough to maintain local adaptation at a scale of a few kilometers. We assessed life‐history traits of 64 D. magna clones originating from 11 populations of a metapopulation with permanent and intermittent pool habitats. We found large within‐ and between‐population variation for all dormancy‐related traits, but no evidence for the hypothesized higher resting‐stage production in animals from intermittent habitats. We discuss how gene flow, founder events, or other forms of selection might interfere with the process of local adaptation.  相似文献   

13.
Along the Canning Basin's Lennard Shelf in Western Australia, the 80‐km‐long Oscar Range is composed of folded Palaeoproterozoic quartzite and phyllite and surrounded by limestones of the Great Devonian Barrier Reef including reef complex, related back‐reef and lagoonal deposits of the Frasnian Pillara Limestone. The range represents an exhumed cluster of palaeoislands. Near the east end of the Oscar Range, a palaeoislet is encircled by the Pillara Limestone showing outward dips that dramatically shallow to expose nearly horizontal bedding planes offshore. From shore and outward, the facies zones observed in the Pillara Limestone include unfossiliferous laminated sediments followed by biozones with abundant Amphipora and Stachyodes, and domal stromatoporoids. An additional outermost lagoonal facies with a diverse molluscan fauna preserved in fine limestone/dolostone is described in this study. High‐spired Murchisonia in a time‐averaged assemblage with other gastropods, bivalves, brachiopods and scaphopods dominate this zone. Uneven distribution of biozones is due to intermittent shoals controlled by the complex relief of basement rocks or recent erosion into underlying layers. The orientations of dendroid stromatoporoids and high‐spired gastropods were analysed to appraise the dynamics of prevailing shoal‐water settings on the inner, more sheltered side of the Oscar Range facing the Devonian mainland to the north. Oscillatory wave action is interpreted as the main agent of transport. Palaeocurrent data for the lighter dendroid stromatoporoids suggest that fair‐weather prevailing winds originated from the SE. Pebble clasts, oncoids, bivalves and gastropods indicate episodes of wave agitation and stronger wind from a SE and southerly direction.  相似文献   

14.
A global data set on forest cover change was recently published and made freely available for use (Hansen et al. 2013. Science 342: 850–853). Although this data set has been criticized for inaccuracies in distinguishing vegetation types at the local scale, it remains a valuable source of forest cover information for areas where local data is severely lacking. Masoala National Park, in northeastern Madagascar, is an example of a region for which very little spatially explicit forest cover information is available. Yet, this extremely diverse tropical humid forest is undergoing a dramatic rate of forest degradation and deforestation through illegal selective logging of rosewood and ebony, slash‐and‐burn agriculture, and damage due to cyclones. All of these processes result in relatively diffuse and small‐scale changes in forest cover. In this paper, we examine to what extent Hansen et al.'s global forest change data set captures forest loss within Masoala National Park by comparing its performance to a locally calibrated, object‐oriented classification approach. We verify both types of classification with substantial ground truthing. We find that both the global and local classifications perform reasonably well in detecting small‐scale slash‐and‐burn agriculture, but neither performs adequately in detecting selective logging. We conclude that since the use of the global forest change data set requires very little technical and financial investment, and performs almost as well as the more resource‐demanding, locally calibrated classification, it may be advantageous to use the global forest change data set even for local conservation purposes.  相似文献   

15.
16.
In a long-term study of sexual behavior in Japanese macaques, we found that matrilineal inbreeding accounted for 2.9% of the copulations recorded for the Arashiyama B troop during 7 mating seasons between 1968 and 1984. Of the 906 copulatory dyads, 46 (5.1%) occurred among kin. Close matrilineal kin dyads (r = 1/2–1/8, 1.1% of the total of copulatory dyads) strongly avoided matrilineal inbreeding, but for remote kin dyads (r > 1/8, 4.0% of the total) the tendency was weaker in some years. Among the possible determinants of matrilineal inbreeding, we found that it tended to occur among younger and lower-ranking males as an effect of troop demographic changes. There is no significant association between female rank and matrilineal inbreeding. Our results are consistent with the hypothesis that different degrees of kin relatedness are discriminated by individuals with respect to mate choice.  相似文献   

17.
A key aspect of successful restoration projects is the sourcing of propagation material suited to the environmental and biotic conditions of the proposed planting site. Traditionally, the use of propagules collected locally has been advocated for revegetation on the assumption that this material is better adapted to local conditions. A rapidly changing climate, however, is challenging the assumption that the use of local genetic stock will provide the best restoration outcome in the long term. We tested the ‘local is best’ paradigm using open top chambers to simulate the predicted summer temperatures for 2050 in western Sydney, Australia. We compared the establishment success of Eucalyptus tereticornis and Themeda australis, dominant species in Cumberland Plain Woodland, grown from local versus non‐local seed. All plants survived an exceptional summer heatwave and few differences between temperature treatments were found. No evidence of local superiority was found for survival or growth of non‐reproductive tissues of either species. However, local provenance plants of E. tereticornis suffered significantly greater herbivory in the ambient temperature treatment than one non‐local provenance, and local provenance plants of T. australis demonstrated significant superiority to most non‐local provenances in all categories of reproductive growth. For both species, the provenances from warmer climates demonstrated comparable, and often better, growth performance than the local provenance plants.  相似文献   

18.
This rereading of Mauss's The gift shifts the focus of discussion from the Maori hau to another example: tanoana (potency) among the Toraja (To Pamona) of Central Sulawesi. This potency animates an exchange with (human) gods that is at once gift and purchase (maoli). By tracing the intersection of this Maussian literature with that on the animist foundation of the Southeast Asian state, I analyse the nature of potent gifts that serve as a form of social currency in a ‘spiritual economy’ tying centre with (Toraja) periphery in the kingdom of Luwu. This ‘money’, imbued with royal potency, is a medium for the payment of debt only and not a medium of exchange, which gives ‘purchases’ made with it the characteristics of a ‘gift’ and also an opportunity to extract tribute. The Maussian analysis of the blurring of person and thing, and of persons and spirits, thus offers new insight into the nature of political power in the Southeast Asian state.  相似文献   

19.
Paired data arises in a wide variety of applications where often the underlying distribution of the paired differences is unknown. When the differences are normally distributed, the t‐test is optimum. On the other hand, if the differences are not normal, the t‐test can have substantially less power than the appropriate optimum test, which depends on the unknown distribution. In textbooks, when the normality of the differences is questionable, typically the non‐parametric Wilcoxon signed rank test is suggested. An adaptive procedure that uses the Shapiro‐Wilk test of normality to decide whether to use the t‐test or the Wilcoxon signed rank test has been employed in several studies. Faced with data from heavy tails, the U.S. Environmental Protection Agency (EPA) introduced another approach: it applies both the sign and t‐tests to the paired differences, the alternative hypothesis is accepted if either test is significant. This paper investigates the statistical properties of a currently used adaptive test, the EPA's method and suggests an alternative technique. The new procedure is easy to use and generally has higher empirical power, especially when the differences are heavy‐tailed, than currently used methods.  相似文献   

20.
Several EU countries import wood pellets from the south‐eastern United States. The imported wood pellets are (co‐)fired in power plants with the aim of reducing overall greenhouse gas (GHG) emissions from electricity and meeting EU renewable energy targets. To assess whether GHG emissions are reduced and on what timescale, we construct the GHG balance of wood‐pellet electricity. This GHG balance consists of supply chain and combustion GHG emissions, carbon sequestration during biomass growth and avoided GHG emissions through replacing fossil electricity. We investigate wood pellets from four softwood feedstock types: small roundwood, commercial thinnings, harvest residues and mill residues. Per feedstock, the GHG balance of wood‐pellet electricity is compared against those of alternative scenarios. Alternative scenarios are combinations of alternative fates of the feedstock materials, such as in‐forest decomposition, or the production of paper or wood panels like oriented strand board (OSB). Alternative scenario composition depends on feedstock type and local demand for this feedstock. Results indicate that the GHG balance of wood‐pellet electricity equals that of alternative scenarios within 0–21 years (the GHG parity time), after which wood‐pellet electricity has sustained climate benefits. Parity times increase by a maximum of 12 years when varying key variables (emissions associated with paper and panels, soil carbon increase via feedstock decomposition, wood‐pellet electricity supply chain emissions) within maximum plausible ranges. Using commercial thinnings, harvest residues or mill residues as feedstock leads to the shortest GHG parity times (0–6 years) and fastest GHG benefits from wood‐pellet electricity. We find shorter GHG parity times than previous studies, for we use a novel approach that differentiates feedstocks and considers alternative scenarios based on (combinations of) alternative feedstock fates, rather than on alternative land uses. This novel approach is relevant for bioenergy derived from low‐value feedstocks.  相似文献   

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