849 research outputs found

    Three New Species of Saccocirrus (Polychaeta: Saccocirridae) from Hawai'i

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    Three new species of saccocirrids from interstitial sand habitats off O'ahu, Hawai'i, are described. Two are from subtidal depths, 9-33 m, and the third is from the intertidal to 3.5 m deep on a fringing reef and at Hanauma Bay, the Marine Life Conservation District and public park. The two deeper-water species, Saccocirrus oahuensis, n. sp. and S. waianaensis, n. sp., have 76-119 and 157-210 segments, respectively; they also have bilateral gonads but lack a pharyngeal pad. The third, S. alanhongi, n. sp., has 35-47 segments, unilateral gonads, and a muscular pharyngeal pad. These species are distinguished from 18 known Saccocirrus spp. by their unique chaetation, number of segments, presence or absence of ventral cilia, and pygidial adhesive structures. Saccocirms oahuensis consumes foraminiferans, and S. alanhongi contained diatoms, unicellular algae, and ostracods. These species add to the interstitial fauna of O'ahu and cooccur with polychaetes Nerilla antennata (Nerillidae) and protodrilids (Protodrilidae), and Kinorhyncha. Saccocirrus alanhongi withstands almost daily disturbance by 600-1200 bathers per day entering the sandy swimming holes in the reef at Hanauma Bay

    Hydropyrolysis: implications for radiocarbon pre-treatment and characterization of Black Carbon

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    Charcoal is the result of natural and anthropogenic burning events, when biomass is exposed to elevated temperatures under conditions of restricted oxygen. This process produces a range of materials, collectively known as pyrogenic carbon, the most inert fraction of which is known as Black Carbon (BC). BC degrades extremely slowly, and is resistant to diagenetic alteration involving the addition of exogenous carbon making it a useful target substance for radiocarbon dating particularly of more ancient samples, where contamination issues are critical. We present results of tests using a new method for the quantification and isolation of BC, known as hydropyrolysis (hypy). Results show controlled reductive removal of non-BC organic components in charcoal samples, including lignocellulosic and humic material. The process is reproducible and rapid, making hypy a promising new approach not only for isolation of purified BC for 14C measurement but also in quantification of different labile and resistant sample C fractions

    Child care support programs for double income families in Korea

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    Lognormal Properties of SGR 1806-20 and Implications for Other SGR Sources

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    The time interval between successive bursts from SGR 1806-20 and the intensity of these bursts are both consistent with lognormal distributions. Monte Carlo simulations of lognormal burst models with a range of distribution parameters have been investigated. The main conclusions are that while most sources like SGR 1806-20 should be detected in a time interval of 25 years, sources with means about 100 times longer have a probability of about 5\% of being detected in the same interval. A new breed of experiments that operate for long periods are required to search for sources with mean recurrence intervals much longer than SGR 1806-20.Comment: 4 pages, latex with seperate file containing 2 uuencoded, gzip'ed, tarred, .eps figures. Replaced with file that does not use kluwer.sty to allow automatic postscript generation. To appear in proceedings of ESLAB 2

    Structured specifications for better verification of heap-manipulating programs

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    Abstract. Conventional specifications typically have a flat structure that is based primarily on the underlying logic. Such specifications lack structures that could have provided better guidance to the verification process. In this work, we propose to add three new structures to a specification framework for separation logic to achieve a more precise and better guided verification for pointer-based programs. The newly introduced structures empower users with more control over the verification process in the following ways: (i) case analysis can be invoked to take advantage of disjointness conditions in the logic. (ii) early, as opposed to late, instantiation can minimise on the use of existential quantification. (iii) formulae that are staged provide better reuse of the verification process. Initial experiments have shown that structured specifications can lead to more precise verification without incurring any performance overhead.

    Popular history and the desire for knowledge : an examination of James A. Michener’s The Source as a popular history of Israel

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    This thesis explores the issues that arise when we consider James A. Michener’s number 1 best-seller The Source (1965) as a popular history of Israel. It examines the educational desires of middlebrow audiences that led to Michener’s popularity, and discusses the benefits and concerns of presenting history in a fictionalised popular form. It then explores how these issues arise within The Source, examining the novel in-depth, arguing that popular history should be cause of greater concern as it has the ability to express particular historical narratives to a wide-reaching audience

    X-Ray Scattering Measurements of the Transient Structure of a Driven Charge-Density-Wave

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    We report time-resolved x-ray scattering measurements of the transient structural response of the sliding {\bf Q}1_{1} charge-density-wave (CDW) in NbSe3_{3} to a reversal of the driving electric field. The observed time scale characterizing this response at 70K varies from \sim 15 msec for driving fields near threshold to \sim 2 msec for fields well above threshold. The position and time-dependent strain of the CDW is analyzed in terms of a phenomenological equation of motion for the phase of the CDW order parameter. The value of the damping constant, γ=(3.2±0.7)×1019\gamma = (3.2 \pm 0.7) \times 10^{-19} eV \cdot seconds \cdot \AA3^{-3}, is in excellent agreement with the value determined from transport measurements. As the driving field approaches threshold from above, the line shape becomes bimodal, suggesting that the CDW does not depin throughout the entire sample at one well-defined voltage.Comment: revtex 3.0, 7 figure

    Nuorten tuettu työkokeilu ja -oppisopimus yrityksessä : Vantaan nuorisopalveluiden malli

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    Alhainen koulutustaso sekä heikko työmarkkinatilanne aiheuttavat merkittäviä syrjäytymisen riskejä useiden nuorten aikuisten elämässä. Nuorten syrjäytyminen on yhteiskunnalle kestämätöntä sekä taloudellisesti, että inhimillisesti. Yksi tapa ehkäistä nuorten syrjäytymistä, on rakentaa heille erilaisia polkuja koulutukseen ja työelämään, sillä koulutuksen katsotaan olevan yksi tehokkaimmista nuorten syrjäytymistä ehkäisevistä toimenpiteistä. Nuoret ovat kiinnostuneita oppisopimuskoulutuksesta muun muassa siksi, että se mahdollistaa toimeentulon ja ammatin hankkimisen samanaikaisesti. Tämän kehittämistyön tavoitteena oli rakentaa ja kuvata prosessi, jonka avulla pääsääntöisesti 18-28-vuotiaat nuoret aikuiset voivat ohjautua Vantaan nuorisopalveluiden kautta työkokeiluun ja oppisopimuskoulutukseen yrityksiin tuetusti. Mallin kehittämisessä on huomioitu sellaisia erityispiirteitä, jotka oppisopimuskoulutuksessa koskevat kouluttamattomia, työttömiä nuoria, joilla on vähän työkokemusta ja jotka tarvitsevat monenlaista tukea. Kehittämistyön laajana tavoitteena voidaan pitää nuorisotakuun toteuttamista paikallisen innovaation avulla, monialaisena yhteistyönä. Opinnäytetyö toteutettiin työelämän kehittämistoimintana, jossa hyödynnettiin aineistona aikaisempia tutkimuksia, raportteja ja selvityksiä sekä monialaisen työryhmän pitkää käytännön kokemusta nuorisotyöstä, nuorten oppisopimustoiminnasta sekä nuorten sosiaalisesta tukemisesta ja vahvistamisesta. Tuloksista käy ilmi, että nuorten oppisopimuskoulutuksessa on tärkeää huomioida kokemattomien nuorten erityinen tuen tarve työpaikoilla tapahtuvassa koulutuksessa. Nuorten kannalta tärkeää on esimerkiksi laadukas työpaikkaohjaus sekä vertaistuki. Nuoret ja työpaikat myös hyötyvät työpaikan ulkopuolisesta, henkilökohtaisesta ohjauksesta ja tuesta, jota voidaan tarjota esimerkiksi nuorisotyön kautta ja jonkinlainen oppisopimukseen suuntaava ennakkojakso, kuten työkokeilu tai muu oppisopimukseen orientoiva toiminta, olisi hyvä sekä työpaikan, että nuoren kannalta. Kehittämistyön tuloksena syntyi prosessikaavio, jossa on kuvattu tuetun työkokeilun ja -oppisopimuskoulutuksen prosessin eteneminen pääpiireittäin. Kehitettyä mallia voidaan hyödyntää Vantaan nuorisopalveluiden työpajatoiminnan yritysyhteistyön toteuttamisessa.The low level of education and the weak labor market situation increases the risks of exclusion in the lives of many young adults. The exclusion of young people is unbearable to society both economically and humanly. One way to prevent the exclusion of young people is to build them different paths for education and working life, because education is seen one of the most effective means to prevent the social exclusion of the young. Young people are interested in apprenticeship training, because among other things, it allows livelihood and obtaining a profession at the same time. The main purpose of this Bachelor´s thesis was to construct and describe a process that allows young adults between the ages of 18 and 28 lead through the youth services of Vantaa to supported work try-out and apprenticeship training to the companies. The development of the model has taken into account the special characteristics of apprenticeship training for unskilled, unemployed young people with low work experience and who need a variety of support. The secondary aim of this development work is to implement the youth guarantee through local innovation and with multidisciplinary co-operation. This thesis was carried out as a workplace development activity utilizing previous research, reports and studies as well as a multidisciplinary team with long experience of youth work, youth apprenticeship training and the social support and strengthening of young people. The results show that in the apprenticeship training of young people it is important to take into account the special needs that young inexperienced people have in the workplace education. It is important for young people to have for example high quality workplace guidance and peer support. Young people and workplaces benefit from personal counselling and support which can be provided for them by the outside provider, such as youth work, and also some kind of orientation (advance period) before the apprenticeship contract, such as the work try-out, would be good for both the workplace and the young. As a result of the development work, a process diagram was developed describing the progress of the process of supported work try-out and apprenticeship training. The developed model can be utilized in the workshop activities in company co-operation of the youth services of Vantaa

    Influence of thermal fluctuations on quantum phase transitions in one-dimensional disordered systems: Charge density waves and Luttinger liquids

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    The low temperature phase diagram of 1D weakly disordered quantum systems like charge or spin density waves and Luttinger liquids is studied by a \emph{full finite temperature} renormalization group (RG) calculation. For vanishing quantum fluctuations this approach is amended by an \emph{exact} solution in the case of strong disorder and by a mapping onto the \emph{Burgers equation with noise} in the case of weak disorder, respectively. At \emph{zero} temperature we reproduce the quantum phase transition between a pinned (localized) and an unpinned (delocalized) phase for weak and strong quantum fluctuations, respectively, as found previously by Fukuyama or Giamarchi and Schulz. At \emph{finite} temperatures the localization transition is suppressed: the random potential is wiped out by thermal fluctuations on length scales larger than the thermal de Broglie wave length of the phason excitations. The existence of a zero temperature transition is reflected in a rich cross-over phase diagram of the correlation functions. In particular we find four different scaling regions: a \emph{classical disordered}, a \emph{quantum disordered}, a \emph{quantum critical} and a \emph{thermal} region. The results can be transferred directly to the discussion of the influence of disorder in superfluids. Finally we extend the RG calculation to the treatment of a commensurate lattice potential. Applications to related systems are discussed as well.Comment: 19 pages, 7 figure

    A complex systems approach to constructing better models for managing financial markets and the economy

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    We outline a vision for an ambitious program to understand the economy and financial markets as a complex evolving system of coupled networks of interacting agents. This is a completely different vision from that currently used in most economic models. This view implies new challenges and opportunities for policy and managing economic crises. The dynamics of such models inherently involve sudden and sometimes dramatic changes of state. Further, the tools and approaches we use emphasize the analysis of crises rather than of calm periods. In this they respond directly to the calls of Governors Bernanke and Trichet for new approaches to macroeconomic modelling.The publication of this work was partially supported by the European Union’s Seventh Framework Programme (FP7/2007-2013) under grant agreement No. 284709, a Coordination and Support Action in the Information and Communication Technologies activity area (‘FuturICT’ FET Flagship Pilot Project). Doyne Farmer, Mauro Gallegati and Cars Hommes also acknowledge financial support from the EU-7th framework collaborative project “Complexity Research Initiative for Systemic InstabilitieS (CRISIS)”, grant No. 288501. Cars Hommes acknowledges financial support from the Netherlands Organization for Scientific Research (NWO), project “Understanding Financial Instability through Complex Systems”. None of the above are responsible for errors in this paper.Publicad
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