Experiences of a Non-Governmental Organisation (NGO) dedicated to the conservation of Arctic char <Emphasis Type="Italic">Salvelinus alpinus</Emphasis> in Ireland

Podocopid ostracods have a calcified carapace encasing their uncalcified body parts like an envelope. A marginal infold (calcified inner lamella) develops along the free margin of both valves, notably in the adult stage. Radial pore canals, which often exhibit a distinct branched shape, can be seen in the free margin and they connect to the space between the outer and inner calcified cuticles called “vestibule.” These characters associated with the marginal infold have been recognized as important criteria both taxonomically and anatomically, but the calcification process of the marginal infold has never been investigated. In this study, we observed the calcification process of the anterior free margin in Leptocythere species. The free margin of the adult specimen starts its calcification just after ecdysis, but the degree of calcification remains the same as in the juvenile until approximately 35 h after ecdysis. The marginal infold of the adult specimen then begins to calcify from its distal part around 40 h postecdysis, and short simple pore canals can still be observed in the free margin. Marginal pore canals become more branched and narrower as calcification proceeds beyond 100 h postecdysis. These results indicate that the calcification of the free margin in a podocopid carapace occurs in two steps, and needs much time to complete the process even in small species of Leptocythere. In addition, these observations provide a basis for discussion on the correlation of the carapace size, environmental factors of the habitat, and the development of the vestibule in some Krithe species, “Krithe problem.”     

Measurement, analysis, and interpretation of mortality factors in insect survivorship studies, with reference to the spruce budworm, Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae)

A theory and practical method are developed to evaluate insect survivorship as a continuous process in time and the effects of major factors that determine it, with a view to providing solutions to certain problems in survivorship studies. There are two ways of assessing mortality rates: nominal and marginal. A nominal rate is based on the number tallied in terms of the immediate cause of death; it depends on the method of observation employed and can be inconsistent between studies. A marginal rate is free of such inconsistency. The marginal rate attributable to the union of parasitism and disease is evaluated by frequent sampling in the field and rearing of each batch of samples in the laboratory for a short period of time. Comparing this rate with the field mortality rate, directly evaluated by sampling, determines marginal predation rate. The marginal parasitism and disease rates cannot be determined by observation. A computational method is developed to evaluate their approximate values. A step-by-step procedure of numerical calculations with data is provided in an appendix. The accuracy of estimating mortality depends on the frequency of sampling in the field and that of inspecting dead individuals in rearing. How frequently sampling and inspection should be conducted is discussed. The method of assessing parasitism developed here has a great advantage over the conventional method based on dissecting the samples, or rearing them through, that often results in a serious underestimation. Also discussed is the relative importance of mortality factors from the pest control point of view, and the concept of “joint contribution” is introduced. Other practical considerations include transportation of samples; rearing conditions; and how to deal with the “dead-in-the-field” in the samples, the “rearing-death syndrome,” and the “virtually dead” individuals. Received: August 25, 2000 / Accepted: May 17, 2001     

History of the development of the temperate forest flora in Kazakhstan,U.S.S.R. from the Oligocene to the Early Miocene

Exact dating of the floras existing in western Kazakhstan during the Oligocene and Early Miocene permits a detailed examination of the formation of a temperate flora during the Rupelian (Early Oligocene), Chattian (Late Oligocene), Aquitanian (the beginning of Early Miocene) and the Burdigalian (end of Early Miocene) Ages and at the same time an establishment of the sequence in the origin and the disappearance of a flora of Turgayan type (the “Turgayan flora” of Kryshtofovich) in Kazakhstan. The most important aspects (composition and terminology) of a previous subtropical flora of a Drevlyanian (possibly Volynian) ecological type (the “Poltavian” flora of Kryshtofovich), which had developed in Kazakhstan and the Ukraine during the Eocene, are also discussed. The text is intended for botanists of various special interests, e.g., paleobotanists, phytogeographers and floristicians, as well as for geologists, especially stratigraphers and paleogeographers. The bibliography comprises more than 200 references and there are seven tables.     

The role of trade-offs in biodiversity conservation planning: Linking local management, regional planning and global conservation efforts

Biodiversity conservation planning requires trade-offs, given the realities of limited resources and the competing demands of society. If net benefits for society are important, biodiversity assessment cannot occur without other sectoral factors “on the table”. In trade-offs approaches, the biodiversity value of a given area is expressed in terms of the species or other components of biodiversity that it has that are additional to the components protected elsewhere. That “marginal gain” is called thecomplementarity value of the area. A recent whole-country planning study for Papua New Guinea illustrates the importance of complementarity-based tradeoffs in determining priority areas for biodiversity conservation, and for designing economic instruments such as biodiversity levies and offsets. Two international biodiversity programs provide important new opportunities for biodiversity trade-offs taking complementarity into account. Both the Millennium Ecosystem Assessment and the Critical Ecosystems or “hotspots” programs can benefit from an explicit framework that incorporates tradeoffs, in which a balance is achieved not only by land-use allocation among areas, but also by the crediting of partial protection of biodiversity provided by sympathetic management within areas. For both international programs, our trade-offs framework can provide a natural linkage between local, regional and global planning levels.     

Does age matter in studying the crustacean eye?

 Fifty randomly selected publications dealing with aspects of crustacean vision had their Materials and methods sections examined. In half of the articles gleaned, only the name of the animal under study was given; the other half mentioned “adult” or “mature” animals; twelve papers provided information on size or age of the experimental animal and six gave the sex. In Petrolisthes elongatus, rhabdom microvilli not only become more regular in outline as the animal grows, but also decrease in diameter from 90.4±21.2 nm in crabs of 5.0–8.9 mm carapace length via 86.6±13 nm in crabs of 9.0–12.9 mm carapace length to 79.7±7 nm in crabs of 13.0–16.9 mm carapace length. Approximately 400 cross sectional diameters of microvilli from identical regions in four eyes of each size class were measured and provided the basis for Anova-, Levene-, and t-tests. The three size classes possess microvilli of significantly different diameters and standard deviations. Our observations show that investigators of the crustacean photoreceptor have frequently neglected to consider the size of their experimental animals, but that this practice should not be continued as the now documented changes in microvillus diameters may influence the amount of visual pigment present and, thus, the photoreceptor’s sensitivity to light. Accepted: 7 May 1996     

Source-sink landscape theory and its ecological significance

Exploring the relationships between landscape pattern and ecological processes is the key topic of landscape ecology, for which, a large number of indices as well as landscape pattern analysis model were developed. However, one problem faced by landscape ecologists is that it is hard to link the landscape indices with a specific ecological process. Linking landscape pattern and ecological processes has become a challenge for landscape ecologists. “Source” and “sink” are common concepts used in air pollution research, by which the movement direction and pattern of different pollutants in air can be clearly identified. In fact, for any ecological process, the research can be considered as a balance between the source and the sink in space. Thus, the concepts of “source” and “sink” could be implemented to the research of landscape pattern and ecological processes. In this paper, a theory of sourcesink landscape was proposed, which include: (1) In the research of landscape pattern and ecological process, all landscape types can be divided into two groups, “source” landscape and “sink” landscape. “Source” landscape contributes positively to the ecological process, while “sink” landscape is unhelpful to the ecological process. (2) Both landscapes are recognized with regard to the specific ecological process. “Source” landscape in a target ecological process may change into a “sink” landscape as in another ecological process. Therefore, the ecological process should be determined before “source” or “sink” landscape were defined. (3) The key point to distinguish “source” landscape from “sink” landscape is to quantify the effect of landscape on ecological process. The positive effect is made by “source” landscape, and the negative effect by “sink” landscape. (4) For the same ecological process, the contribution of “source” landscapes may vary, and it is the same to the “sink” landscapes. It is required to determine the weight of each landscape type on ecological processes. (5) The sourcesink principle can be applied to non-point source pollution control, biologic diversity protection, urban heat island effect mitigation, etc. However, the landscape evaluation models need to be calibrated respectively, because different ecological processes correspond with different source-sink landscapes and evaluation models for the different study areas. This theory is helpful to further study landscape pattern and ecological process, and offers a basis for new landscape index design. __________ Translated from Acta Ecologica Sinica, 2006, 26(5): 1444–1449 [译自: 生态学报]     

A comparison of cut roses from Ecuador and the Netherlands

Purpose  

There is a need to assess social impacts of products along the full life cycle, not only to be able to address the “social dimension” in sustainability, but also for potentially improving the circumstances of affected stakeholders. This paper presents a case study for a social life cycle assessment (S-LCA) based on the recently published “Guidelines for Social Life Cycle Assessment of Products” developed by the United Nations Environment Programme/Society of Environmental Toxicology and Chemistry (UNEP/SETAC) working group. General aim is to “try out” the proposed method. The case study itself compares the impacts of rose production in Ecuador with the Netherlands. Furthermore, the objective is to identify differences and similarities in environmental and social life cycle modelling and both social and environmental hot spots in each of the life cycles.     

Nerves in the endodermal canals of hydromedusae and their role in swimming inhibition

N eoturris breviconis (Anthomedusae) has a nerve plexus in the walls of its endodermal canals. The plexus is distinct from the ectodermal nerve plexuses supplying the radial and circular muscles in the ectoderm and no connections have been observed between them. Stimulation of the endodermal plexus evokes electrical events recorded extracellularly as “E” potentials. These propagate through all areas where the plexus has been shown by immunohistology to exist and nowhere else. When Neoturris is ingesting food, trains of “E” potentials propagate down the radial canals to the margin and cause inhibition of swimming. This response is distinct from the inhibition of swimming associated with contractions of the radial muscles but both may play a part in feeding and involve chemoreceptors. Preliminary observations suggest that the “E” system occurs in other medusae including Aglantha digitale (Trachymedusae) where the conduction pathway was previously thought to be an excitable epithelium.     

Elongated microvilli support the sea urchin embryo concentrically within the perivitelline space until hatching

Summary The early sea urchin embryo is supported in a concentric position within the perivitelline space by elongated microvilli which are attached to the fertilization envelope by extracellular matrix fibers. This “attachment complex,” of microvillus tip: extracellular matrix fibers: fertilization envelope, was revealed by two methods: the use of pronase or calcium-free sea water to dissolve the extracellular matrix fibers, thus causing the eggs to lose their concentric location, and the visualization of the “attachment complex” using video-enhanced differential interference contrast microscopy and transmission electron microscope images. The presence of the “attachment complex” helps in understanding two types of early developmental events: (1) the apparently continual change in microvillus length during cleavage stages which retains the embryos in their concentric position and (2) the hatching process.     

Ontogeny of the electric organ discharge and the electric organ in the weakly electric pulse fish Brachyhypopomus pinnicaudatus (Hypopomidae, Gymnotiformes)

I recorded the electric organ discharges (EODs) of 331 immature Brachyhypopomus pinnicaudatus 6–88 mm long. Larvae produced head-positive pulses 1.3 ms long at 7 mm (6 days) and added a second, small head-negative phase at 12 mm. Both phases shortened duration and increased amplitude during growth. Relative to the whole EOD, the negative phase increased duration until 22 mm and amplitude until 37 mm. Fish above 37 mm produced a “symmetric” EOD like that of adult females. I stained cleared fish with Sudan black, or fluorescently labeled serial sections with anti-desmin (electric organ) or anti-myosin (muscle). From day 6 onward, a single electric organ was found at the ventral margin of the hypaxial muscle. Electrocytes were initially cylindrical, overlapping, and stalk-less, but later shortened along the rostrocaudal axis, separated into rows, and formed caudal stalks. This differentiation started in the posterior electric organ in 12-mm fish and was complete in the anterior region of fish with “symmetric” EODs. The lack of a distinct “larval” electric organ in this pulse-type species weakens the hypothesis that all gymnotiforms develop both a temporary (larval) and a permanent (adult) electric organ. Accepted: 1 March 1997     

Subpopulation of nestin positive glial precursor cells occur in primary adult human brain cultures

Glial fibrillary acidic protein (GFAP) is an intermediate filament protein considered to be the best astroglial marker. However, the predominant cell population in adult human brain tissue cultures does not express GFAP; these cells have been termed “glia-like” cells. The basic question about histological origin of adult human brain cultures remains unanswered. Some authors showed that “glia-like” cells in adult human brain cultures might be of non-glial origin. We examined primary explant tissue cultures derived from 70 adult human brain biopsies. Within first 5–10 days approximately 5–10% of the small explants became attached. Outgrowing cells were mostly flat cells. These cells formed confluent layer over 3–6 weeks in culture. At confluence the cultures contained 2–5% of microglial cells, 0.1% GFAP-positive astrocytes, less than 0.01% oligodendrocytes and 95–98% GFAP-negative “glia-like” cells. This population of flat “glia-like” cells was positively stained for vimentin, fibronectin, and 20–30% of these cells stained for nestin. Our findings revealed that 1 mM dibutyryl-cAMP addition, in serum free conditions, induced a reversible stellation in 5-10% of the flat “glia-like” cells but did not induce the expression of GFAP or nestin in morphologically changed stellate cells. These results demonstrate that “glia-like” cells in primary adult human brain cultures constitute heterogeneous cell populations albeit with similar morphological features. Two distinct subpopulations have been shown: (i) the one immunostained for nestin; and (ii) the other reactive for dibutyryl-cAMP treatment.     

Vemakylindrus cantabricus, a new species of Diastylidae (Crustacea, Cumacea) from the northern Iberian coasts

Eleven species of the genusVemakylindrus Bacescu, 1961 are known at present. A hitherto unknown species is described herein asV. cantabricus, sp. nov., and is compared with the more closely related congeneric species:V. hastatus (Hansen, 1920) andV. stebbingi Day, 1980.Vemakylindrus cantabricus may be distinguished from its congeners by a combination of the following characters: (1) carapace densely covered by hooked denticles and hairs; (2) pseudorostrum shorter than carapace; (3) telson of “Diastylis type” with 5–6 pairs of lateral spines; and (4) external process of basis of third maxilliped with 4 long plumose setae.     

Ecological explanations for successful invasion of exotic plants

The intentional introduction of exotic species can increase the level of local biodiversity, enrich people’s material lives, and bring significant social and economic benefits that are also the symbols of human progress. However, along with the frequent intercourse among countries and regions, the frequency of uncontrolled crossregional migration of species is increased and there is a lack of scientific management strategy for the intentional introduction of exotic species. Exotic species invasion, which is behind habitat fragmentation, has become the second largest threatening factor to the maintenance of the global-scale level of biological diversity. Exotic species invasion can destroy the structure of an ecosystem, disturb the economic life of a society, and do harm to human health. In this paper, the authors review some of the ecological explanations for issues such as “what causes or mechanisms have led to the successful invasion of exotic species”, including the “ideal weeds characteristics”, “biodiversity resistance hypothesis”, “enemies release hypothesis”, “evolution of increased competitive ability hypothesis”, “niche opportunity hypothesis”, and “novel weapon hypothesis”. The authors also analyze and evaluate the background and theoretical basis of the hypotheses, providing explanations for some phenomena, as well as the deficiencies of these explanations.     

A century of oceanographic and fisheries exploration on the continental shelf off Argentina

A detailed analysis is presented of the main contributions, both local and international, to the fields of oceanography and fishery sciences resulting from exploratory cruises carried out on the continental shelf off Argentina over the last 100 years. The end of the 19th century is chosen as a starting point for this analysis as it marks the beginning of active marine research by Argentinian scientists and an accumulation of information on Antarctic and Subantarctic organisms in foreign journals. Mention is also made of previous contributions derived from the classic expeditions and global circumnavigational voyages during the 18th and 19th centuries. Although the aims of those were not always strictly oceanographic, they rendered significant information to this field of knowledge. In the early years, references arose mainly from the particular geographic situation of the Argentinian shelf, a necessary passage in the navigation routes to the Pacific Ocean, and later on the way to Antarctica. Sources of information are divided into four categories: (a) foreign scientific projects in the area; (b) investigation by Argentinian scientists and research vessels; (c) joint projects between Argentinian and foreign institutions; and (d) contributions from sources other than oceanographic cruises (commercial navigation, maritime weather reports, satellite images, etc.). The analysis includes an updated and classified bibliographical list of the main contributions to the fields of oceanography and fishery sciences derived from those sources, published either in international or local journals or appearing as technical and internal reports. The motivations, objectives and main achievements of foreign surveys and programmes in the area and their impact on local scientific progress are discussed. The early sixties mark a turning point in the evolution of international research in the area. The creation of biological stations along the Argentinian coast, and the support given to the pooling of human resources set the basis for the development of bilateral programmes. Similar progress in Brazil and Uruguay led to the outgrowth of regional activities. Joint scientific efforts described in this analysis include the programmes carried out by the research vessels of Germany (“Walther Herwig”, “Meteor”), Japan (“Kaiyo Maru”, “Orient Maru”, “Shinkai Maru”), Poland (“Professor Siedlecki”), Russia (“Evrika”, “Dimitry Stefanov”) and the USA (“Vema”, “Atlantis II”), the achievements of which are a landmark in the evolution of marine science in the aea.     

Further portrayal of epithelial monolayers emergent de novo from extirpated ascidians palleal buds

Astogeny in botryllid ascidians is executed by highly synchronized, repeated development and death cycles operating simultaneously on three coexisting asexually derived generations: zooids, primary buds, and secondary buds. In this study, we validated the fact that surgically removed blastogenic stage “D” primary buds cultured under in vitro conditions, away from any discrete colonial regulatory cues, exhibit intrinsic phenomena that are probably masked by astogenic controls. They produce de novo epithelial monolayers (EM), extending their lifespan from a few days to 1 mo and up to 5 mo when floating in the medium. Enhanced EM formation was documented when fibroblast growth factor (FGF) was added after at least 24 h incubation in FGF-free medium. Surprisingly, with no FGF administration, while intact isolated buds did not develop any EM, injured buds developed EM in half of the cases. Working on actin, PL10, FGF-R, P-MEK, MAP-kinase, and cadherin expressions, we documented that extirpated buds and monolayers are very active on the molecular/biochemical levels, revealing various cells and cellular organelle stains and rapid changes in the protein levels along a daily basis. Cells situated in the center of the monolayers stained differently for some proteins than peripheral cells. Cumulatively, results showed that flattened attached monolayers, as well as free-floating stage “D” buds, are highly active, not only exhibiting differential expressions of various proteins along incubation, but are also highly responsive to physical damages. These results establish a novel in vitro model system for epithelial cell development and senescence, revealing surprising rejuvenation and extended lifespan phenomena.     

Life cycle assessment of automotive fuels: critical analysis and recommendations on the emissions inventory in the tank to wheels stage

Purpose  

As new alternative automotive fuels are being developed, life cycle assessment (LCA) is being used to assess the sustainability of these new options. A fuel LCA is commonly referred as a “Well To Wheels” analysis and calculates the environmental impacts of producing the fuel (the “Well To Tank” stage) and using it to move a car (the “Tank To Wheels” stage, TTW). The TTW environmental impacts are the main topic of this article.     

Quantum Information Processing in the Wall of Cytoskeletal Microtubules

Microtubules (MT) are composed of 13 protofilaments, each of which is a series of two-state tubulin dimers. In the MT wall, these dimers can be pictured as “lattice” sites similar to crystal lattices. Based on the pseudo-spin model, two different location states of the mobile electron in each dimer are proposed. Accordingly, the MT wall is described as an anisotropic two-dimensional (2D) pseudo-spin system considering a periodic triangular “lattice”. Because three different “spin-spin” interactions in each cell exist periodically in the whole MT wall, the system may be shown to be an array of three types of two-pseudo-spin-state dimers. For the above-mentioned condition, the processing of quantum information is presented by using the scheme developed by Lloyd.     

Mating behavior of the rock catfish, Silurus lithophilus

The mating behavior of the rock catfish Silurus lithophilus (Siluriformes: Siluridae), a species endemic to the Lake Biwa system, was observed from May to July in 1989–1994 along the rocky shore of the lake's outlet, the Seta River. The mating behavior of S. lithophilus involved a certain behavioral sequence: “chasing,”“clinging,” and “enfolding” while “squeezing” by the male; and “circling” by the spawned pair. The mating behavior of this species was basically similar to that of S. biwaensis, but greatly different from that of S. asotus, which spawns in running water (in ditches). The mating behavior of S. lithophilus (and S. biwaensis) might have developed as an adaptation to lentic environments such as the shores of the large river or the lake. Received: October 25, 2000 / Revised: February 25, 2001 / Accepted: March 8, 2001