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The aim of this study was to valorize the hemicellulose-rich liquid fraction (liquor) arising from hydrothermal pretreatment of sugarcane bagasse (SCB) through its utilization as an unconventional, soluble carbon source for the production of hemicellulases, namely xylanases and α-L-arabinofuranosidases (ABFases), by Aspergillus niger DCFS11. Through the use of factorial design, pretreatment conditions producing liquors optimized for either early- or late-phase enzyme production were identified. Subsequent deep characterization of liquor components using liquid chromatography and mass spectrometry was performed to identify compounds likely responsible for hemicellulase induction. SCB liquors arising from various pretreatment configurations induced up to 2- and 8.6-fold higher xylanase and ABFase production, respectively, by A. niger DCFS11 than raw SCB substrate owing to the strong inducing potential of arabinosylated xylooligosaccharides and free arabinose solubilized during pretreatment. Notably, unlike the severe pretreatment conditions required for maximum cellulose saccharification and ethanol yields during biomass conversion, low severity and low biomass loading are required if enzyme production from liquor is desired at early-phase growth with no additional detoxification steps. This suggests that for effective application in biorefineries, separate or multi-step processes would be required to optimize both hemicellulase production by A. niger DCFS11 and cellulose digestion. This work demonstrates the potential of hydrothermal pretreatment of lignocellulosic substrates as a tool to increase the production of enzymes by filamentous fungi.  相似文献   
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Assessing population density is crucial for studying the ecology and evolutionary biology of species as well as for conservation purposes. Here we used point count methods to infer population density in a single-island endemic passerine bird, the Réunion Grey White-eye Zosterops borbonicus, that displays striking evidence of differentiation at a small spatial scale. Population density was estimated at 5.17 birds ha?1 (CL 4.85–5.50), a value somewhat higher than previously believed. This estimation provides the first detailed estimation of bird population density in the vulnerable summit ecosystems of Réunion and will possibly allow a better understanding of the evolutionary causes of this plumage colour variation.  相似文献   
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We investigated the hunting strategies of wild common marmosets (Callithrix jacchus) to determine whether the strategies differed among animals of different age classes and/or prey type. The study was conducted in a fragment of Atlantic Rain Forest, situated 40 km from Recife (PE/Brazil). Twenty‐seven individuals from four social groups were observed. Captured prey items were divided into three categories. The hunting strategies of the common marmosets were ranked into four categories. The acquisition of larger prey (items more than 2.0 cm) involved the appropriate body movements and postures that concealed the approaching marmosets, whereas the acquisition of smaller prey (items under 2.0 cm) involved less concealing behaviors. Furthermore, adults and juveniles (age ≥5 months) were more capable of capturing larger prey than were younger (1–2 months) or older infants (3–4 months). Although older infants were successful in capturing certain prey, they often failed when they attempted to capture larger prey that jumped and/or used flight to escape. The results suggest that both the experience of the monkeys and escape behavior of the prey affect predation efficiency in wild common marmosets. Am. J. Primatol. 72:1039–1046, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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Biotechnology Letters - Endophytic fungi are microorganisms capable of colonizing the interior of plant tissues without causing damage to them. The study of the secondary metabolites produced by...  相似文献   
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Background

Viewed through the micro focus of an interpretive lens, medical anthropology remains mystified because interpretivist explanations seriously downplay the given context in which individual health seeking-behaviours occur. This paper draws upon both the interpretivist and political economy perspectives to reflect on the ethno medical practices within the Korean-Australian community in Sydney.

Methods

We draw on research data collected between 1995 and 1997 for an earlier study of the use of biomedical and traditional medicine by Korean-Australians in Sydney. A total of 120 interviews were conducted with a range of participants, including biomedical doctors, traditional health professionals, Korean community leaders and Korean migrants representing a range of socio-economic backgrounds and migration patterns.

Results and Discussion

First, the paper highlights the extent to which the social location of migrants in a host society alters or restructures their initial cultural practices they bring with them. Second, taking hanbang medicine in the Korean-Australian community as an illustrative case, the paper explores the transformation of the dominant biomedicine in Australia as a result of the influx of ethnomedicine in the era of global capitalism and global movement.

Conclusion

In seeking to explain the popularity and supply of alternative health care, it is important to go beyond the culture of each kind of health care itself and to take into consideration the changes occurring at societal, national and global levels as well as consequential individual response to the changes. New social conditions influence the choice of health care methods, including herbal/alternative medicine, health foods and what are often called New Age therapies.  相似文献   
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We investigated the potential use of call playback for surveying the elusive golden-backed uakari (Cacajao melanocephalus), a diurnal social primate that typically inhabits the relatively inaccessible black-water swamp forests of the upper Amazon (Igapó forest) during the wet season. Furthermore, our objective was to understand better the functions of vocalisations of these rare and threatened monkeys. We focussed on the “tchó” call, a loud vocalisation that varies in temporal and frequency characteristics according to behavioural context and individual signaller (Bezerra et al. in Int J Primatol, 2010b). We investigated the vocal and behavioural responses of golden-backed uakaris from three Igapó areas to three different playback stimuli: own group calls (OGC); neighbouring group calls (NGC); and control (background noise). The call stimuli were used to simulate the unexpected presence of monkeys from the monkeys’ own and neighbouring Igapó areas. Playback of OGC and NGC increased calling and altered behaviour in golden-backed uakaris, whereas no noticeable response occurred to the control stimuli. Furthermore, there was no evidence of habituation to the call stimuli and the natural behavioural pattern of the groups was not obviously affected. Hence, call playback seems to be a valuable tool for locating these elusive monkeys in river surveys. Most of the agonistic-related behaviour observed after NGC playback was also observed after OGC playback. As golden-backed uakaris are not territorial, the presence of strange conspecifics to the area may not necessarily represent a more threatening situation. Our methods and results may also be useful for surveys of other primate species living in the Igapó forest and in other habitat types.  相似文献   
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