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1.
The presence of several types of allelochemicals has been reported from Ajuga, a Labiatae genus comprising more than 40 species of wide distribution in extratropical regions of both hemispheres. The genus is of great medicinal and economic importance and among the biological properties of the secondary metabolites, the antifeedant activity against pest insects appears to be related to the presence of neo-clerodane type diterpenes. This review focuses on the isolation and structural elucidation of this type of compounds from Ajuga species and the hemisynthetic compounds of closely related structure obtained. The reported biological activity of crude extracts and isolated diterpenes will be briefly commented.
Josep CollEmail:
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2.
Mycena aphanes and Mycena exilis, belonging to section Filipedes and section Polyadelphia, are proposed as new species. They are described and illustrated and compared to other species in the two sections. Mycena aphanes is a strikingly characteristic Mycena with fulvous or yellowish brown colours of both pileus and stipe. Mycena exilis is characterized by its occurrence on fallen Salix leaves, a pale brown pileus, occasionally with a pale pink tinge, narrowly adnate lamellae, four-spored basidia, and the presence of clamp connections.
Gro GuldenEmail:
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Indigenous knowledge is unevenly distributed. Individual knowledge level may be affected by many factors such as gender, age, ethnicity, profession, religious and cultural beliefs, abundance and usefulness of the species. This study documents indigenous knowledge of herbaceous and woody plant species of farmers and herders in southwestern Niger. Specifically, we examine the effects of age, gender, and ethnicity on knowledge of local vegetation. Results from the study showed that on average a higher proportion of woody species was identified by the respondents compared to herbaceous species. Both gender and ethnicity had a significant effect on the identification of herbaceous species but no effect on identification of woody species. Respondents in lower age group (10 to 30 years) identified lower number of species compared to other age classes. There seems to be a curvilinear relationship between age of respondents and number of plant species identified. Results from this study reaffirm the uneven distribution of indigenous knowledge within a given area due to social factors. The main challenge is how to incorporate these social differences in knowledge of native plant species into sustainable management and conservation of community natural resources.
Augustine A. AyantundeEmail:
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5.
The sexual pattern and sexual development of the leopard grouper, Mycteroperca rosacea, were investigated from 483 specimens collected from the Gulf of California, Mexico. Histological and population data indicated a gonochoric sexual pattern. Some juveniles passed through an immature bisexual phase of gonadal development, but no evidence of post-maturational sex change was found. The immature bisexual phase is believed to be associated only with male development. The size distribution and size at sexual maturity were similar for both males and females. In accordance with predictions of the size-advantage model, the gonochoric sexual pattern of M. rosacea is likely influenced by its group-spawning mating system.
Brad E. ErismanEmail:
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6.
Summary  The tree species Berlinia korupensis Mackinder & Burgt is described as new. The species is endemic to the southern part of Korup National Park in Cameroon. Seventeen trees have been found so far, the largest being 42 m high and having a trunk diam. of 88 cm. The new species is assessed as Critically Endangered (CR D) under the criteria of IUCN. Two distribution maps are included; one map indicating the single locality in Cameroon near the Nigerian border where the new species was found and another map of the permanent plot where 14 of the 17 trees were recorded. A line drawing is also included, along with colour photographs of the flowers and the trunk.
Barbara A. MackinderEmail:
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7.
Predictive performance modelling of parallel component compositions   总被引:1,自引:0,他引:1  
Large-scale scientific computing applications frequently make use of closely-coupled distributed parallel components. The performance of such applications is therefore dependent on the component parts and their interaction at run-time. This paper describes a methodology for predictive performance modelling and evaluation of parallel applications composed of multiple interacting components. In this paper, the fundamental steps and required operations involved in the modelling and evaluation process are identified—including component decomposition, component model combination, M×N communication modelling, dataflow analysis and overall performance evaluation. A case study is presented to illustrate the modelling process and the methodology is verified through experimental analysis.
Stephen A. JarvisEmail:
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8.
Aglaia bourdillonii is a plant narrowly endemic to the southern portion of the Western Ghats (WG), in peninsular India. To understand its ecological and geographic distribution, we used ecological niche modeling (ENM) based on detailed distributional information recently gathered, in relation to detailed climatic data sets. The ENMs successfully reconstructed key features of the species’ geographic distribution, focusing almost entirely on the southern WG. Much of the species’ distributional potential is already under protection, but our analysis allows identification of key zones for additional protection, all of which are adjacent to existing protected areas. ENM provides a useful tool for understanding the natural history of such rare and endangered species.
M. Irfan-UllahEmail: Email:
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9.
The reaction of N-demethylation plays an important role in the degradation of some alkaloids in a number of organisms. This review presents how our understanding of the N-demethylation of nicotine in plants has been improved through studies in cell cultures of Nicotiana plumbaginifolia and N. glutinosa using a variety of isotopic techniques. The overall aim is to understand how metabolism recycles the alkaloid skeleton, both in terms of the metabolic route(s) exploited and the reaction mechanisms of the enzymes involved. The former has been approached using high-resolution 2-dimensional NMR and GC-MS methods; the latter by determining kinetic isotope effects and modelling the potential reaction steps. It appears that the mechanism for nicotine demethylation in plants is similar to but has significant differences from that described for mammals and Pseudomonas bacteria. These differences are discussed.
Richard J. RobinsEmail:
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10.
Competition for pollination is thought to be an important factor structuring flowering in many plant communities, particularly among plant taxa with morphologically similar and easily accessible flowers. We examined the potential for heterospecific pollen transfer (HPT) in a community of four Acacia species in a highly seasonal tropical habitat in Mexico. Partitioning of pollen flow among sympatric species appears to be achieved, in part, through segregation of flowering in seasonal time, and interspecific differences in pollinator guilds. However, two coflowering species (Acacia macracantha and Acacia angustissima) shared multiple flower visitors, raising the possibility of HPT. Each of these coflowering species showed high intraspecific daily synchrony in pollen release, but dehisce at different times of day. Pollinators rapidly harvested available pollen from one species before abandoning it to visit the flowers of the second later in the day. The activity of shared pollinators, predominantly bees, is thus structured throughout the day, and potential for HPT reduced. Suggestive evidence in favour of a resource partitioning explanation for this pattern is provided by the fact that A. macracantha showed significantly greater intraspecific synchrony when coflowering with a potential competitor (A. angustissima) than when flowering alone. We discuss our results in light of previous work on coflowering acacia assemblages in Tanzania and Australia. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Nigel E. RaineEmail:
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11.
Frequently occurring red heartwood decisively restricts the volume of light-coloured beech wood, which can be processed to high-grade appearance products. Forestry and wood industry lack suitable means for maximising the yield of light timber, since the intra-tree extent of red heartwood varies considerably. The present study characterised in detail the intra-tree shape of red heartwood and its relationships to tree-external traits (dead branches, branch scars), considered as possible initiation points of red heartwood formation. An experimental method based on log scanning and image analysis was developed and applied. Using its output for three-dimensional visualisation and data analyses, external traits being linked to the local red heartwood shape were identified. Furthermore geometric relationships were established for characterising these external traits and for deriving discriminating criteria.
H. WernsdörferEmail:
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12.
The maintenance of exceptionally high numbers of folk varieties by the Piaroa people of the Venezuelan Amazon is considered. We cataloged 113 manioc folk varieties, their nomenclature, use and relevant characters, revealing significant insights into the role of manioc in Piaroa social life. Through a qualitative investigation of the cultivation, processing and symbolic significance of manioc (Manihot esculenta) in two Piaroa regions over a period of 18 years, we have found that such agrobiodiversity can only be fully explained by a combination of multiple factors, including pragmatic and ecological considerations, the subtle and complex diversity of Piaroa manioc preparations and a variety of sociocultural factors, such as manioc’s role as a mediator of social relationships and as a marker of cultural and social heritage.
Stanford ZentEmail:
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13.
Despite growing interest in traditional and local ecological knowledge for conservation and resource management, the role of migrant resource users is largely unexplored. Challenging many assumptions about what constitutes “local knowledge,” migrant and immigrant harvesters of non-timber forest products on the Olympic Peninsula, Washington possess useful ecological knowledge of overstory–understory relationships and how forestry practices affect understory biological and commercial production. Harvesters of salal (Gaultheria shallon), a shrub used in the multi-million dollar floral greens industry, were interviewed in Mason County, Washington in 2001–2003. Interviews revealed that harvesters possess different kinds of resource management knowledge depending on whether they are experienced harvesters or more recent newcomers to the area. These differences may also correlate with differences in their harvesting practices. Understanding how resource management knowledge differs between experienced and newcomer harvesters can inform forest managers in their efforts to develop effective management and permitting policies for floral greens and other non-timber forest resources in the Pacific Northwest of the United States.
Heidi L. BallardEmail:
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The insect-pathogenic fungus Ophiocordyceps sinensis (better known as Cordyceps sinensis) is harvested over much of the Himalayan plateau as a highly prized remedy in traditional Oriental medicine. Over the past 10 years its financial value has increased dramatically, with collectors paid as much as US $12,500 kg−1 for top-quality material. This is causing significant distortion to local economies, and there is widespread concern that the current rate of collection is unsustainable. This paper introduces the fungus and its insect hosts, documents some of the biological and social constraints to achieving sustainability, describes the socioeconomic climate within which harvest and sale occurs in Bhutan, and details the measures put in place by the Royal Government of Bhutan to promote wise management of this valuable natural resource.
Paul F. CannonEmail:
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17.
Questions centered on the development of local and traditional ecological knowledge and the relationship of that knowledge to the development of conservation and management practices have recently attracted critical attention. We examine these questions with respect to the dynamic commercial fisheries of the Canadian province of Newfoundland and Labrador. The knowledge of fish harvesters coevolves with fishing practices and is embedded in a dynamic socioecological network that extends into and beyond the fisher, fishery households, and communities to include management, technologies, markets, and marine ecological conditions. Changes in these networks have moved knowledge and practices related to fishing in directions defined by policy, science, economic rationality, and new ecological realities. We characterize this movement as a shift along a continuum from local ecological knowledge (LEK) towards globalized harvesting knowledge (GHK) as harvesters become increasingly disconnected from socioecological relationships associated with traditional species and stocks. We conclude with a discussion of how LEK/GHK have interacted over time and space with other knowledge systems (particularly science) to influence management, and suggest that contingent, empirical evaluations of these interactions will provide a fruitful avenue for future interdisciplinary research.
Grant MurrayEmail:
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18.
19.
The new enchytraeid species Lumbricillus healyae sp. n. is described from freshwater streams, with well-oxygenated and poorly mineralised waters, situated in Byers Peninsula (Livingston Island, South Shetland Islands, Antarctica). Lumbricillus healyae sp. n. is morphologically close to L. antarcticus and L. incisus, and it is mainly distinguished by the structure of the spermatheca with a short, distinct ectal duct, the oval penial bulb (greatest diameter in the transverse body axis) associated with strong dorso-ventral muscular fibres, and a protrusible pseudopenis. A second undetermined Lumbricillus species is described from a small stream. Study specimens are not fully mature; however, the highly irregular form and size of the testis-sac lobes and the absence of a penial bulb encapsulated under a muscular layer are remarkable. It is probably related to a small group of Lumbricillus species reported from the Antarctic maritime region (L. colpites, L. griseus and L. aestum), characterised by the structure of the male duct, which ends in a simple pore surrounded by glands.
Eugenio RicoEmail:
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20.
The loggerhead sea turtle (Caretta caretta), one of the three sea turtle species inhabiting the Mediterranean Sea, is an endangered species. However, although frequently treated in marine animal rescue centers, and the subject of several studies in literature, as yet, few studies have been conducted on large numbers of loggerhead sea turtles in order to establish physiological reference ranges that enable the identification of pathological values. The lack of studies on reference parameters probably depends on the fact that marine turtles treated in wildlife rescue centers are usually in a critical conditions, thus precluding the collection of data on healthy animals and compromising the reliability of any data obtained from them. The present biological study was therefore conducted in order to obtain a database from healthy animals in natural conditions. Serum biochemistry and serum protein electrophoresis were performed on blood samples obtained from 65 healthy adult loggerhead sea turtles captured and delivered to the Sea Turtle Rescue Center of Linosa (Italy); the blood samples were collected during the clinical examination of rescued animals. Laboratory analyses of serum samples were made in order to establish reference parameters, commonly required for laboratory diagnoses in mammals and diseased animals.
D. GelliEmail:
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