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The Po river plain (northern Italy) is delimited to two mountain ridges, the Alps and the Apennines. It hosts peculiar lowland man-modified springs, locally known as "fontanili", which originate from natural resurgences occurring along the alluvial fans of the main watercourses, namely in the transition zone from the higher to lower plain which is characterized by changes in slope profile and sediment granulometry. These habitats usually show low variation in hydrological, hydrochemical and thermal conditions throughout the year. Twenty-eight springs, located in the provinces of Lodi and Cremona (Lombardy) in the alpine sub-catchment of the Po river were sampled in summer and autumn of 2004. Twenty-three of them were typical alluvialfan springs, while the remaining five were terrace springs. The two groups of springs showed marked differences in their hydrochemical and hydrological characteristics. Sixteen ostracod species in three families (Candonidae, Ilyocyprididae, and Cyprididae) were identified. The most frequent species were Cypria ophtalmica (19 sites), Herpetocypris reptans (16), and Prionocypris zenkeri (13). Five species were found only once: Chlamydotheca incisa, Scottia pseudobrowniana, Pseudocandona compressa and Candona neglecta. Up to 6 taxa were recorded from a single site and the average number of taxa for each site was c. 3. The associations among ostracod taxa and their occurrence in relation to environmental factors were examined. Finally, the results of this survey were compared with a similar study previously conducted in 31 alluvial fan springs of the apennine sub-catchment of the Po river. [ABSTRACT FROM AUTHOR]

The post-embryonic development of the appendages of the Cyprididae ostracod Heterocypris salina (Brady, 1868) are described in detail and compared with those of other podocope species documented in previous studies. Generally, the appearance of limbs during onotgeny of H. salina is similar to that of other species, but small differences in limb morphologies were identified between H. salina and other Cyprididae species, including other Heterocypris species. Some features appear either earlier or later in the development of H. salina compared with other species, even species of the same genus. These features may be useful characters for phylogenetic analyses at the genus and family levels. [ABSTRACT FROM AUTHOR]

Two new species of Fabaeformiscandona and collections of Fabaeformiscandona japonica (Okubo, 1990. Bulletin Biogeography Society of Japan 45: 39-50) from Japan have provided an opportunity to study the copulatory behaviour and sexual morphology of these species. The male uses the large fifth limb palps to force open the female carapace for copulation. However, the female has an enlarged overlapping flap over the posterior of the carapace which appears to hinder the male from opening the carapace, thus the female retains some control over potential mates. During copulation, the males' fifth limbs, caudal ramus and m process of the hemipenes and the females' protrusion of the female reproductive organ play a crucial role in providing a secure interface between the sexual organs to allow for the transfer of the giant spermatozoa. Development of the sexual organs in both sexes begins during the A-2 instar, and the protrusion of the female genital lobe begins to form during the A-1 instar. [ABSTRACT FROM AUTHOR]

Asexual lineages lack the means to purge their genomes of (deleterious) mutations through recombination. Evolutionary theory thus predicts that such lineages will be prone to early extinction. In brooding animals, brood selection might provide a mechanism to counter the accumulation of mutations. Of the three putative ancient asexual animal groups, only the darwinulid ostracods are brooders. Here, we test the incidence of egg and juvenile abortion in a darwinulid species, Penthesilenula brasiliensis, under two temperature treatments. Part of the offspring is released without brooding (close to 30% in one treatment). The majority of these aborted eggs hatches and develops. As it is unlikely that females are such bad judges of offspring quality, either the surviving animals will present deficiencies later on in development (brood selection) or early egg release can be a (bet-hedging) strategy to increase fecundity in favourable conditions. [ABSTRACT FROM AUTHOR]

In podocopid ostracods, the "hingement", with teeth/sockets or crenulations, is developed along the attached dorsal margin of the carapace. Dual calcified lamellae, called "duplicatures" are also developed along the free margin. However, the terminology of these marginal areas is often confused by many ostracodologists because of their differing interpretations and viewpoints. In this study, the marginal areas of the carapace were observed in detail, using the transmission (TEM) and scanning (SEM) electron microscopes. Consequently, the terminology of the marginal areas has been revised. The homology between attached and free margins and the structural differences of duplicatures, for some taxa are also discussed. [ABSTRACT FROM AUTHOR]

The arrangement of hepatopancreas and associated cells was examined in freshwater cypridoidean ostracods in the context of comparative microanatomy and cytology using light (LM) and transmission electron microscopy (TEM). A compact, short, subpyriform hepatopancreas located at the sides of the front part of the fore gut has been observed in the following species of the family Candonidae: Candona candida, C. neglecta, Cyclocypris ovum, Cypria ophtalmica, Fabaeformiscandona fabaeformis, Pseudocandona compressa. Within the families Cyprididae (in species Cypridopsis vidua, Herpetocypris reptans, Heterocypris incongruens, Potamocypris unicaudata and Psychrodromus olivaceus), Ilyocyprididae (Ilyocypris gibba) and Notodromadidae (Notodromas monacha, N. persica) a completely different arrangement of the hepatopancreas was observed. In these families the hepatopancreas is tubular and remarkably elongated. Hepatopancreatic cells (sometimes very large) are scattered within a more or less developed layer of other cell types. This organ is also connected to the fore gut. However, it stretches, in comparison with the candonids, much further in the rear part of the body cavity and in the interlamellar space. In transversal and longitudinal sections this organ forms typical lacunae. The lacunae are often longitudinally further subdivided forming a lacunary system. It means that there are often distinct constrictions in some parts of the tubular hepatopancreas. The hepatopancreas verges into multilayer cellular formations (MCFs) in caudal and more peripheral areas. The MCFs can occupy large spaces in the periphery of the body cavity, within the bases of appendages or in the interlamellar space. The morphology of the hepatopancreatic cells in the part close to the fore gut distinctly differs in appearance from the cells in the more caudal areas. The cells in the MCFs strongly resemble "Subdermalzellen" in earlier literature. The development of MCFs often reflects the amount of food in the both parts of the middle gut. The extent and spatial arrangement of the MCF is subject to a high variability. In TEM the hepatopancreatic cells resemble oenocytoid cells described for example in insects. The ultrastructure of some parts of the hepatopancreas viewed in TEM represents typical cecal cells forming a basal labyrinth and microvilli. These specialized cells most probably originate from the hepatopancreatic cells, which are also able to give rise to plasmatocytes. [ABSTRACT FROM AUTHOR]

The posterior end of body of the extant ostracods exhibits a pair of variously shaped appendages, commonly designated as furca(e), uropods or caudal rami, used for feeding and/or locomotion. It is here shown that the socalled furca of all extant ostracods has evolved from the (probably epipodal) vibratory plates of a pair of uropods. The transformation comprised the following steps: (a) complete reduction of the uropodal protopodite and endopodite; (b) sclerotisation of the lateral walls of the vibratory plates; (c) transformation of the branchial filaments into spines and/or claws; (d) re-orientation of the plates from posterodorsal to posteroventral. These modifications are suggested to have evolved in parallel with a change in function, from respiratory to locomotory and/or feeding. The most primitive condition, reminiscent of the ancestral state of character, is seen in the Platycopida: the ‘furca' still appears similar in shape to the vibratory plates of the pair of sixth limbs. In the Podocopida the uropodal plates have been modified into plate-like, more often into rod-shaped rami mainly used for locomotion. In both the Platycopida and Podocopida the anus has remained in its original place, posterior to the ‘furcal' plates or rami. In the Myodocopida and Halocyprida the uropodal vibratory plates are transformed into heavily developed lamellae bearing sturdy spines. They are activated by a complex apparatus of muscles and sclerites, the development of which necessitated the displacement of the anus from the end of the body towards its present place, anterior to the ‘furca'. The furca of the Ostracoda being not a ‘true' furca, a change in terminology is proposed: uropodal plates or lamellae in the Platycopida, Palaeocopida and Myodocopida/Halocyprida; uropodal rami in the Podocopida. The so-called furcae of the Ostracoda being homologous structures, it is concluded that all extant ostracods belong to a monophyletic lineage. [ABSTRACT FROM AUTHOR]

The contribution deals with evolutionary and taxonomic aspects of the stygobitic ostracod lineage Pseudocandona eremita (Ostracoda, Candonidae). It is based on a comparative study of the morphology of both the carapace and limbs of individuals belonging to eight populations from Romania (three reproducing bisexually, the others by parthenogenesis). Left valves display various outline shapes, classified in two morphotypes, the "dorsally rounded shape" and the "triangular shape". The intra- and interpopulation shape variability of these valves is described using geometric morphometrics and multivariate statistics. It is shown that the more flat carapace occurs frequently in populations living in gravel-sand habitats. Moreover, variability of 12 morphological limb characters taken on females is quantitatively evaluated by discriminant analysis. The character state of the m process of the male copulatory organ gives the most reliable information for the separation of the three bisexual populations in different species: P. serbani Danielopol, P. danubialis sp. nov. and P. transylvanica sp. nov. Short descriptions of the latter two species are presented. For the five parthenogenetic populations where no particular discriminant trait could be found, a solution of compromise is adopted, i.e. they are temporary assigned to Pseudocandona eremita (Vejdovský, 1882, Thierische Organismen der Brunnenwässer von Prag. Prag) sensu lato. [ABSTRACT FROM AUTHOR]

With respect to Middle Devonian ostracods from western Canada, special cases of palaeocopine extradomiciliar dimorphism are discussed, as in the opinion of many workers are unusual for younger hollinoideans and, in particular, primitiopsoideans. Although the general view that velar dimorphism is the main characteristic of Mid Palaeozoic Palaeocopina is basically not wrong, dimorphic histial structures, even though less conspicuous in aspect, have been recognised in some Mid-Devonian hollinoideans, specifically hollinids and ctenoloculinids. This is now also proven to be true of distinct hollinellids and, by the way, discrete primitiopsids, while distinguishing between narrow-based projections (ridges, flanges, spines) and broad-based protrusions (e.g. lobes). Whereas the former may occur in velar as well as histial situations, lobal features are especially found in the histial position. Special attention is paid to false primitiopsids, being (with some caution) grouped in the Hollinoidea (Family unknown). Essentially, three genera are new or redefined (former left under open nomenclature): Gen. aff. Abditoloculina: multilobate in aspect, lobal (histial) dimorphic; Gen. aff. Gravia: coalesced velar dimorphic; Bisphenella: histial dimorphic. With respect to the hold discussion about ostracod phylogeny, the updated standard classification scheme is given, as applied to Palaeozoic, non-myodocopine ostracods. Reduction of dimorphism in palaeocopines is considered to be an apomorphic character, lack of dimorphism assumed to indicate asexual reproduction. At the same time, a plea is made in favour of reviving Treatise revision. [ABSTRACT FROM AUTHOR]

Although the area of Lake Yeniçağa is a potential candidate for RAMSAR convention, several anthropogenic factors compromise its biological diversity. This is mostly due to nutrient- rich water released from both point and nonpoint sources. Thirteen ostracod taxa (Candona neglecta, C. candida, Ilyocypris bradyi, Darwinula stevensoni, Cypridopsis vidua, Physocypria kraepelini, Cypria ophtalmica, Prionocypris zenkeri, Eucypris virens, Herpetocypris reptans, Pseudocandona compressa, Fabaeformiscandona fabaeformis Potamocypris cf. fulva) were found during this study. Potamocypris cf. fulva is a new record for the Turkish freshwater ostracod fauna. The first nine of these species have broad geographic ranges, implying high tolerance levels to different environmental variables. Based on the estimated species optima and tolerance levels, two species exhibited higher effective number of occurrences (C. neglecta, and D. stevensoni, respectively) than the other species. Three species (C. neglecta, D. stevensoni, I. bradyi) did not show significant correlation with any environmental variable we used. Both Canonical correspondence (CCA) and Pearson correlation analyses showed that temperature was the most effective predictor of species occurrence, followed by electrical conductivity and redox potential. In contrast, pH and dissolved oxygen of water were the least effective predictors. Approximately 71% of the correlation between community composition and environmental variables was explained by the first axis of the CCA diagram, which had a relatively low (7.7%) cumulative variance of species. The lower (560 µg/l) and the upper (2030 µg/l) levels of ammonia (NH3) exceeded the limits during winter season. The concentrations of total coliform and Escherichia coli bacteria were measured up to 10 × 107 cfu/ml and 10 × 103 cfu/ml, respectively. Results of physicochemical measurements, microbiological counts, and species data indicate that water quality of Lake Yeniçağa has been rapidly deteriorated by anthropogenic factors that are the main threat for not only the lake's aquatic diversity but also human health around the lake. [ABSTRACT FROM AUTHOR]

Ostracods have long been studied by scientists because their fossil remnants provide a valuable tool for the reconstruction of past environmental changes, including climate change and anthropogenic eutrophication. Relatively little is known about the physiology, behaviour and reproductive ecology of recent forms. We argue that filling this gap in knowledge requires stable cultures that can be used in laboratory studies. Here we provide quantitative information on the food preference of the common non-marine ostracod Eucypris virens. Using an experimental device allowing a free choice of eight food items, including both autoand heterotrophic organisms, observations were carried out on groups of animals from different populations. Our results indicate that E. virens highly prefers spinach and the cyanobacterium Tolypothrix tenuis to other food items. The latter also plays an important role in maintaining the quality of the culture medium and provides a convenient substrate for moulting and egg-laying. As such, we recommend Cyanobacteria like T. tenuis as a food source for long-standing cultures of E. virens, and other non-marine ostracod species. [ABSTRACT FROM AUTHOR]

An attempt has been made at a comprehensive study of the diversity and distribution of subterranean ostracods in the Pilbara region, northwestern Australia. The area is a "hot spot" for subterranean biodiversity, some of which is currently under threat from extensive mining operations. Both bore and well sites were targeted, totalling 445 sites, to obtain a thorough coverage of the 200,000 km2. In addition, physical and hydrochemical measurements were obtained for all of the samples (temperature, conductivity, dissolved oxygen, pH, Eh, turbidity, nutrients, major ions). Ostracods were retrieved from approximately 47% of the samples and 56% of the sites. Twenty-one genera and around 110 species of ostracods have been identified. Of these, 72 are new species and a further 10 are currently in open nomenclature, due to the lack of suitable material for formal taxonomic description. The Candoninae are particularly well represented with 12 genera; some, such as Areacandona and Deminutiocandona, with 25 and 10 species respectively. Most sites (80%) were dominated by only one or two species, with up to six species at some sites. Population density varied from 1-370 individuals/sample. The most abundant and diverse sites occur in fresh, bicarbonate-rich aquifers utilised for water extraction, such as Pannawonica (Robe River), Cane River and Millstream. There is a clear distinction between taxa at the genus level from coastal and low-lying alluvial sites, and upland sites (>300 m altitude). Beyond this, the majority of species are confined within a surface water catchment, or in many cases, a specific aquifer. There are, however, some morphological similarities of the carapaces between different species within similar hydrogeologic settings. Ornate and ridged-valved species are common in the Mg-HCO3 waters of the Newman and Marillana Creek areas, whereas smooth-shelled, tapered forms are prevalent in alluvial aquifers. The more saline, Na-Cl rich aquifers at the edge of Great Sandy Desert have a particularly distinctive fauna, including one almost triangular species. The distribution of the stygobitic ostracod species in relation to the hydrogeology and water chemistry is discussed. [ABSTRACT FROM AUTHOR]

Spatial and temporal distribution, abundance and habitat preferences of ostracod assemblages were studied in various habitats of Lake Fehér in Hungary. Of the 20 species Fabaeformiscandona hyalina and Cypridopsis hartwigi are new to Hungary. Significant spatial differences were recorded in the composition and abundance of the Ostracoda assemblages in the different habitats. The most diverse and abundant assemblages were found in the reed-belt, however, the mean abundance of the species differed in the different macrophyte communities of the reed-belt. The species richness and abundance were considerably lower in disturbed sites than in the other habitats. Most of the 20 species showed distinct habitat preferences and ecological tolerances. Especially the presence and coverage of the vegetation and the dissolvedoxygencontent influenced the distribution and abundance of the species. [ABSTRACT FROM AUTHOR]

The population structures of the three dominant planktonic halocyprid Ostracoda species in Admiralty Bay (King George Island, Antarctic Peninsula) were followed throughout the course of a year in zooplankton samples collected once every three weeks from February 1993 to January 1994. The sampling was conducted at two stations: A in the central part of Admiralty Bay (400-0 m) and B in the entrance to the Bay from the Bransfield Strait (400-0 m). The samples were taken using a WP-2 net (square mouth opening of 0.196 m2 and 200 µm mesh) hauled vertically from the bottom to the surface. Changes in the age structures of the populations of three species Alacia belgicae, Alacia hettacra and Metaconchoecia isocheira were tracked. Their population structures differed. The changes in A. belgicae suggested that it reproduces year-round, whereas both A. hettacra and M. isocheira probably complete their life cycles within a year. The cycle in A. hettacra probably starts earlier in the year than that of M. isocheira. Populations of A. belgicae and M. isocheira were more advanced in their development at station A, than at station B, but A. hettacra was more advanced at the latter. Advection appears to play a role in maintaining the populations in the shelf waters. Comparisons between populations in the shelf area (Admiralty Bay) and in open ocean waters (Croker Passage) show that the M. isocheira population is older in shelf water whereas the age structure of A. belgicae population is not influenced by the locality. [ABSTRACT FROM AUTHOR]

In order to enrich the knowledge on ostracods in Serbia, field work was carried out in the central and southern part of the Banat district during 2002 and 2003. Samples from the collection of the Institute of Zoology, Faculty of Biology in Belgrade were also examined. Altogether, 133 samples were investigated. In this research, 23 ostracod species were found. Most of them have a Palaearctic distribution. Ilyocypris decipiens, Bradleycypris obliqua and Tanycypris pellucida are new to the faunas of Serbia and Montenegro, as is the subfamily Cypricercinae. Three species were found again after several decades, including a new and stabile population of Candona natronophila Petkovski, 1969. The most frequent species were Cypridopsis vidua and Physocypria kraepelini. Statistical analysis of ostracod communities and their relations to measured ecological variables is also given. [ABSTRACT FROM AUTHOR]

We describe Terrestricythere proboscidis sp. nov. from a littoral interstitial habitat at Orito Beach, Matsumae, southern Hokkaido, Japan, a site characterized by coarse sand with many pebbles. This is the fifth known species of the ostracod superfamily Terrestricytheroidea, the first interstitial species of the superfamily, and the first record of the superfamily from Japan. The new species is clearly distinguished from its four known congeners by its small carapace with a transversely flat ventral margin, and the seventh limb consisting of four podomeres; its hemipenis has a long, S-curved process. We also report here the habitat, microdistribution, and locomotory behavior of the new species. Quantitative sampling revealed that the species lives in an interstitial environment. T. proboscidis is euryhaline. Behavioral observations showed that T. proboscidis cannot swim, but uses its appendages to push itself among sediment grains. An analysis of variance showed temperature and grain size, as well as temperature-depth and temperature-grain size interactions, to be significant influences on variation in population density. Sediment moisture content is correlated with these variables and likely is a primary factor in this species' microdistribution. [ABSTRACT FROM AUTHOR]

Planktonic ostracods are deep dwelling mesozooplankton that are diel migrators and detritus feeders. In the Humboldt Current region off Peru they are shown to be strongly influenced by El Niño conditions. Species composition and distribution were compared in day and night (vertically hauled 50-0 m Hensen Net) samples that were collected from three latitudinal zones (3°40′ S-6°S; 9°S-12°S and 15°S-18°S) during 1998 (El Niño year) and in 2001 (a year with usual upwelling regime). Unexpectedly, ostracods diversity and abundance were much higher during El Niño than during the upwelling regime. Tropical species that normally occurred north of 6°S, spread southwards and increased in abundance; Euconchoecia aculeata was often dominant, particularly in coastal waters, and the frequency of occurrence of others increased throughout the entire region (e.g. Porroecia porrecta, Archiconchoecia striata). Conversely, Conchoecetta giesbrechti, a species associated with subsurface oxygen minimum waters, was more frequently found and in higher abundance during the upwelling regime in 2001. Thus, El Niño conditions apparently favor the occupation of the epipelagic zone by many halocyprid species advected in from tropical waters, possibly because the higher oxygen content in the subsurface waters enables these diel migrating species to survive better. Additional factors may be a consequence of the switch to a picoplankton production cycle, which results in more detritus being retained in the upper waters, and the sharp reduction in planktivorous fishes such as the anchovy which may reduce the predation pressure they experience. [ABSTRACT FROM AUTHOR]

During the earliest Triassic, the neritic environments were completely devastated and the recolonization of biotopes was very slow. Besides some small foraminifera and bivalves, ostracods are among the few neritic organisms that were able to survive and/or to thrive in the inhospitable environments after the disaster events. But the Permian-Triassic boundary marks also a great change in the ostracod assemblages. The Palaeozoic ostracods left room for the "modern" fauna. New data on the Early Triassic neritic fauna in South China (Sichuan and Guangxi Provinces) and bibliographic synthesis on other areas yield a first description of the timing of this turnover. First "typically modern" forms appear already in the Late Permian. The Early Triassic (Griesbachian to Spathian) ostracod faunas display a mixture of Palaeozoic and Mesozoic taxa. Completion of the Palaeozoic-Mesozoic turnover could be located in the Middle Triassic (Anisian). [ABSTRACT FROM AUTHOR]

Fifteen International Symposia on Ostracoda (ISO) have been organized between 1963 and 2005, each of them followed by one or more proceedings volumes. In the present study, 906 titles presented at the occasion of one of these fifteen symposia were evaluated regarding their prevailing and their secondary theme or method, thus obtaining a retrospective on the history of ostracod research between ISO1 and ISO15. This review may help in moving ostracodology into the 21st century. [ABSTRACT FROM AUTHOR]

Hematopoietic stem cells (HSCs) provide the basis for the enormous regenerative capacity of the hematopoietic system. Despite the need for a lifelong production of blood cells, replicative exhaustion seems to affect the HSC pool. Erosion of telomeres, protective structures at the ends of eukaryotic chromosomes, limits the replicative life span of most somatic cells. The expression of telomerase, the enzyme synthesizing telomeres de novo, is restricted to highly proliferative cells like germ line cells and tumor cells. Adult stem cells such as HSCs still exhibit telomerase activity to a certain level. Here, the telomerase activity does not prevent telomere shortening, suggesting a restriction of the proliferative capacity of HSCs. In this review, we discuss the relevance of telomere maintenance, potential functions of telomerase, and possible clinical applications of telomere manipulation in the hematopoietic stem cell compartment. Furthermore, we discuss new insights affecting the aging of the hematopoietic stem cell pool besides replicative exhaustion. [ABSTRACT FROM AUTHOR]

New semiconductor technologies offer the possibility to realize complex mixed-signal electronic systems performing multiple tasks and operating at high frequencies. Whereas in digital design abstractions are easily made of various non-ideal physical effects, these phenomena do have a great influence on analog systems. As a result, designing analog circuits is a complicated and time-consuming task, even for analog systems containing only a fraction of the number of devices typically found in their digital counterparts. Automation and design re-use are heavily exploited in digital design, while analog design depends more on the experience of the designer. To close this productivity gap between digital design practice and the capabilities of the technology on one hand and the traditional analog design processes on the other hand, analog EDA tools are most welcome. [ABSTRACT FROM AUTHOR]

The modeling strategy based on the development of generic behavioral models as described in the previous part allows to represent several systems of classes of architectures at different levels of abstraction. Interaction schemes derived from simulation approaches in both the time and frequency domain can be adopted as explained in the previous chapters. An efficient way to represent designs and to calculate their performance values is only one part of a design strategy. Indeed, question remains which architecture and parameter values to select during the specialization of the generic behavioral model. Therefore, the synthesis strategy presented in this chapter completes the design strategy based on generic behavior introduced in Chap. 3. [ABSTRACT FROM AUTHOR]

The analog designer frequently characterizes the behavior of a system using frequency-domain properties. Therefore, representation and simulation of analog and mixed-signal systems directly in the frequency domain can naturally serve as base elements for building generic behavioral models. For efficient use in a design flow, such models should be suited both for time-efficient evaluation of the model via simulation, and for analysis to identify both intended and parasitic signal flows in an architecture. To be able to write frequency-domain generic functions according to these requirements, a mathematical framework is presented in this chapter. Together with a specific interaction scheme for a wide class of front-end architectures, frequency-domain generic behavioral models for efficient top-down design are obtained. [ABSTRACT FROM AUTHOR]

Generic behavioral models describe the behavior of an entire class of analog or mixed-signal system instead of directly representing a particular architecture with specific non-idealities. This allows to widen the design space of architectures covered by the model while the common characteristics of the systems in the class can be exploited to yield time-efficient performance evaluation methods. To offer these properties, systems are described in an indirect way via generic functions and an interaction scheme. These elements are closely related to the evaluation method of the model via simulation: the interaction scheme expresses the dynamic relations between the generic functions. Time- and frequency-domain approaches are commonly used in analog design. Both can be adopted as intrinsic simulation scheme for the generic behavioral model. This chapter focuses on the time-domain techniques that are developed in this work whereas frequency-domain models are discussed in the next chapter. [ABSTRACT FROM AUTHOR]

The analog designer at the start of the 21st century has several design strategies at his or her disposal to synthesize a well-functioning electronic system. Which strategy to choose depends on issues like the complexity of the system with respect to size and performance requirements, the available computational power, and the technology used to produce the end product. Furthermore, different modeling and synthesis strategies can be selected during different stages of the design process. [ABSTRACT FROM AUTHOR]

As electronic systems tend to offer more functionality and consume less power, the design complexity continuously increases. As a result, design automation is an indispensable aid to deliver first-time-right and optimized designs in a time-to-market as short as possible. Successful development of EDA tools starts with the definition of a systematic methodology. Whereas for digital systems systematic high-level synthesis is commonly employed, analog synthesis is more ad hoc, especially at higher abstraction levels. This chapter first describes the kind of analog and mixed-signal systems targeted in this work. Then, the fundamental properties of design flows for these systems are summarized. Finally, a general methodology for high-level analog and mixed-signal synthesis is presented which provides a framework for developing analog EDA tools. [ABSTRACT FROM AUTHOR]

In the sixth century B.C., the Greek philosopher Thales of Miletus discovered that rubbing amber leads to attraction of small objects, a phenomenon now known as static electricity. Today, more than 2,500 years later, electricity plays a vital role in modern society in various domains, like communication, energy, transportation, health services, domestic comfort, industrial processes and entertainment. As a result of this electrical revolution, the world consumed about 16 billion MWh electricity in 2006, more than twice the consumption of 25 years ago, and continuously increasing. [ABSTRACT FROM AUTHOR]

Telomere maintenance has been shown to be essential for unlimited growth potential of human cells and is regarded as one hallmark of cancer. Telomere repeats at the ends of eukaryotic chromosomes are synthesized by the enzyme telomerase, which is active in most cancers and to some extend also in normal somatic cells. Therefore, targeting the telomerase/telomere complex offers great potential for the development of novel anticancer therapeutics. An example of such a strategy is the small molecule BIBR1532 that is a selective, non-nucleosidic inhibitor of the catalytic component hTERT. Treatment of cancer cells with this compound leads to progressive telomere shortening, consecutive telomere dysfunction, and finally growth arrest after a lag period that is largely dependent on initial telomere length. We have additionally shown that using this class of telomerase inhibitor at higher concentrations exerts a direct cytotoxic effect on malignant cells of the hematopoietic system but not on normal stem cells, which appears to derive from direct damage to the structure of individual telomeres. [ABSTRACT FROM AUTHOR]

A key challenge in the engineering of Ge MOSFETs is to develop a proper Ge surface passivation technique prior to high-κ dielectric deposition to obtain low interface state density and high carrier mobility. A review on some possible treatments to passivate the Ge surface is discussed. Another important aspect is the activation of p- and n-type dopants to form the active areas in devices. Finally, Ge deep submicron n- and p-FET devices fabricated with this technique on germanium-on-insulator substrates, yield promising device characteristics, showing the feasibility of these substrates. [ABSTRACT FROM AUTHOR]

Recent advances in micro-electronics make the study of the migration of even small marine animals (>12 cm) over many 1000s of kilometres a serious possibility. Important assumptions in long-term studies are that rates of tag loss caused by mortality or tag shedding are low, and that the tagging procedure does not have an unacceptable negative effect on the animal. This paper reports results from a study to examine the retention of relatively large (24 × 8 mm) surgically-implanted dummy acoustic tags over a 7-month period in steelhead pre-smolts (O. mykiss), and the effects of implantation on growth and survival. Although there was some influence on growth to week 12, survival was high for animals > 13 cm FL. In the following 16-week period, growth of surgically implanted pre-smolts was the same as the control population and there was little tag loss from mortality or shedding. Currently available acoustic tags can be implanted in salmonid fish ≥12 cm FL, although combined losses from mortality and tag shedding were 33-40% for animals in the 12 and 13 cm FL size classes. By 14 cm FL, combined rates of tag loss (mortality plus tag shedding) for surgically implanted tags dropped to <15% and growth following surgery was close to that of the controls. Our results suggest that studies of ocean migration and survival over periods of many months are now feasible even for animals as small as salmon smolts. Surgically implanted salmon smolts are therefore good candidates for freshwater and coastal ocean-tracking studies on relatively long time scales (months). On such time scales, even relatively small salmon smolts may move thousands of kilometers in the ocean. [ABSTRACT FROM AUTHOR]

Aquaculture of sea bass is widely spread in the Mediterranean and employs a variety of husbandry protocols that need to be evaluated in terms of fish well-being. Behavioural tests can be used as operational indicators of short-term stress, because changes in swimming performance and/or muscle activity (e.g. electromyograms) can be interpreted as response associated with a wide variety of stressors. Diagnostic procedures, based on physiological telemetry, will thus enable appropriate mitigative strategies to be implemented to ensure the well-being of cultured fish. The objective of this study was to examine the contribution of two muscle types to the swimming activity of sea bass (Dicentrarchus labrax, L. 1758). Hard-wire technology was used to ‘fine-tune' measures obtained using a physiological transmitter. Fine-tuning showed that the aerobic muscle displayed an increase in recruitment of muscle fibres relative to increasing swimming speed up to 0.6-0.7 ms−1 of the Ucrit, where the anaerobic (white muscle) activity started to exponentially augment with swimming speed, reaching up to ∼7 times its initial value. Intensity of electromyogram signals were described by logarithmic (red muscle): y = 0.5922Ln(x) + 1.2251 (R2 = 0.9906) and exponential (white muscle): y = 0.0977e2.4723x (R2 = 0.9845) relationships. Fine-tuning indicated that the two muscle types in the sea bass are involved in fuelling swimming activity below the Ucrit. Thus, scope for activity is not supported solely using aerobic metabolism, though the red muscle powers the majority of the swimming ability. Measurement of Ucrit displayed an average value of 3.43 BLsec−1 (SE = 0.12). Associated EMG values measured during the forced swim trials using an implanted bio-sensitive radio transmitter showed that EMG's intensity increased, on average, 3.2 times between 0.2 msec−1 and the Ucrit velocity (∼1 msec−1). Above EMG values were fine-tuned using estimates obtained from direct monitoring of the red and white musculature. Overall, the results demonstrated that the scope for activity, previously thought to represent only aerobic metabolism, is composed of both aerobic and anaerobic pathways. Fine-tuning of physiological transmitters to measure activity of free ranging fish can therefore be utilised to monitor the proportion of the scope of activity utilised in response to external stressors. This proportion and the level of compensatory ability remaining could represent a measure of well-being in cultured fish. [ABSTRACT FROM AUTHOR]

Active tracking of passive integrated transponder (PIT)-tags using portable antennae is becoming an increasingly common technique in fish habitat studies in shallow rivers. We carried out "blind testing" to test the efficacy (% tags found) and accuracy (distance between predicted and true tag location) of a portable antenna system (Texas Instruments) in winter conditions using 23-mm PIT-tags. Up to 90 cm reading range was achieved and signals penetrated ice, rock, wood and water. In the "blind test" trials, a majority of the hidden tags (N = 12-30) were found indicating high tracking efficacy. PIT-tags that were oriented with their cylindrical axis parallel to the plane of the antenna coil inductor loop resulted in a bimodal detection field that had low detection range in the centre of the loop. The utilization of this bimodal detection field proved to be a very accurate method for identifying tag position (mean ± SE distance from predicted to true tag location 10.9 ± 1.4 cm) and thus well suited for microhabitat and activity studies in winter conditions. Aggregations of tags (multiple tags within 1 m2) and obstacles for the antenna maneuvering (e.g., boulders, logjams) reduced the pinpointing accuracy (mean ± SE 13.3 ± 1.8 cm), but the reduction in accuracy was statistically non-significant between the single and aggregated tags. [ABSTRACT FROM AUTHOR]

Radio-tagging is widely used for studies of movements, resource use and demography of land vertebrates, with potential to combine such data for predictive modelling of populations from individuals. Such modelling requires standard measures of individual space use, for combination with data on resources, survival, dispersal and breeding. This paper describes how protocols for efficient collection of space-use data can be developed during a pilot study, and reviews the ways in which such data can be used for space-use indices that help answer biological questions, with examples from a study of riverine pike (Esox lucius). Analyses of diurnal activity and spatio-temporal correlation were used to assess when to record locations, and analyses of home range increments were used to define the number of location records necessary to assess seasonal ranges. We stress the importance of developing protocols that use minimal numbers of locations from each individual, so that analyses can be based on samples of many individuals. The efficacy of link-distance (e.g. cluster analysis) and location density (e.g. contouring) techniques for spatial analysis for river fish were compared, and the utility of clipping off areas to river banks was assessed. In addition, a new automated analysis was used to estimate distances along river mid-lines. These techniques made it possible to quantify interactions between individuals and their habitat: including a significant increase in core range size during floods, significant preference for deep pools, and a lack of exclusive territories. [ABSTRACT FROM AUTHOR]

A whole-lake acoustic telemetry array was utilized to monitor the three-dimensional position of 20 largemouth bass (Micropterus salmoides). Code division multiple access (CDMA) technology enabled the simultaneous monitoring of the 20 transmitters (equipped with pressure and temperature sensors) at 15 s intervals with sub-meter accuracy. Fish were monitored between November 2003 and April 2004 to evaluate the behaviour of fish across different temporal and spatial scales. The distance moved by largemouth bass, assessed both on a daily and hourly basis, varied by season and was positively correlated with water temperature. For example, daily movement rates were 2.69 ± 1.45 km/day in mid November (average daily water temperature 5.9°C), 2.24 ± 0.73 km/day in early January (5.1°C), and 7.28 ± 2.62 km/day in mid April (7.7°C). Interestingly, daily movement rates varied by as much as 25 fold among individual fish. Visualization of fish swimming paths revealed that whereas some fish occupied discrete areas and made only localized movements, other individuals made lengthier journeys covering much of the lake in periods of as little as one day. Analysis of fish behaviour at a finer temporal scale revealed that during the winter, fish spend more than 95% of their time swimming at speeds less than 0.1 m/s (0.07 ± 0.24 m/s). During late fall, and especially in spring, swimming speeds were higher with mean swimming speeds of 0.11 ± 0.27 m/s and 0.19 ± 0.29 m/s, respectively. When the telemetry dataset was queried to simulate 24 h manual tracking intervals, it was clear that manual tracking data would not have been representative of actual daily movement rates, underestimating daily movement and swimming speeds by at least 75 fold. This study identifies the importance of evaluating fish activity at multiple spatial (whole lake to sub-meter position) and temporal (seasonal to seconds) scales and illustrates the potential of CDMA telemetry to yield such data. [ABSTRACT FROM AUTHOR]

Winter habitat use and activity patterns of juvenile Atlantic salmon and brown trout were analysed in a comparative study between Passive Integrated Transponder (PIT) technology, radio telemetry and underwater observation by snorkelling. Two study periods were conducted in Stoney River, Newfoundland, Canada. During Study period I, 49 juvenile Atlantic salmon (fork length: 11.0-18.0 cm) and 7 brown trout (11.0-17.3 cm) were tagged with PIT tags and/or radio transmitters in late winter of 2004. During Study period II, 18 juvenile Atlantic salmon (fork length: 12.0-18.4 cm) and 23 brown trout (10.9-20.8 cm) were tagged and tracked twice a day at 10:00 h and 22:00 h on five consecutive days in late winter of 2005. From the 56 fish released during Study period I, on average 19.6 ± 6.0% of the PIT tagged fish and 99.3 ± 2.2% of the radio tagged fish were relocated during any given survey. Over the Study period II, 39% of fish emigrated from the study site. PIT technology had an efficiency of 39.2 ± 14.1% to detect the remaining fish. In contrast, radio telemetry relocated on average 96.9 ± 6.5% of the tagged fish whereas by snorkelling on average only 4.1 ± 5.6% of the tagged fish were observed. PIT telemetry may however be more efficient in smaller, less heterogeneous streams. The advantage of PIT technology over radio telemetry is clearly that it is relatively less costly permitting higher numbers of individuals to be tagged and there is no limit in the operational life of the transponder. In winter, juvenile salmonids preferred low flow velocity and no preferences were observed for any specific water depth over the range of available water depths. Fish selected preferentially boulder habitat over other substrates in the environment. Habitat utilisation did not differ between day and night. The use of winter preference indices may be important for future habitat modelling. [ABSTRACT FROM AUTHOR]

The optimal antenna of transmitters used in small aquatic animals is often a compromise between efficient radio wave propagation and effects on animal behavior. Radio transmission efficiency generally increases with diameter and length of the conductor, but increased antenna length or weight can adversely affect animal behavior. We evaluated the effects of changing antenna length and material on the subsequent tag output power, reception, and detection of tagged fish. In a laboratory, we compared the relative signal strengths in water of 150 MHz transmitters over a range of antenna lengths (from 6 to 30 cm) and materials (one weighing about half of the other). The peak relative signal strengths were at 20 and 22 cm, which are approximately one wavelength underwater at the test frequency. The peak relative signal strengths at these lengths were approximately 50% greater than those of 30 cm antennas, a length commonly used in fisheries research. Few significant differences were present in distances for the operator to hear or the telemetry receiver to decode transmitters from a boat-mounted receiving system based on antenna length, but the percent of tagged fish detected passing a hydroelectric dam fitted with an array of receiving systems was significantly greater at the antenna length with peak output power in laboratory tests. This study indicates careful choice of antenna length and material of small transmitters can be used to reduce weight and possible antenna effects on animal behavior, to maximize tag output power and detection, or to balance these factors based on the needs of the application. [ABSTRACT FROM AUTHOR]