2,192 research outputs found

    Ecological Studies On Vectors Of Malaria, Japanese Encephalitis And Filariasis In Rural Areas Of West Java

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    Penangkapan rutin nyamuk dewasa dilakukan dua kali sebulan selama 1 jam pada waktu senja pada badan kerbau, babi dan manusia dan juga dikerjakan penangkapan dengan light trap. Daerah penangkapan meliputi satu daerah dataran rendah Jakarta (semi urban) dan empat daerah pedalaman di Jawa Barat yang ekologinya berbeda-beda dan dimana sawahnya 2 kali panen dalam satu tahun. Penangkapan nyamuk satu malam penuh dari jam 18.00 - 16.00 dikerjakan disalah satu daerah pedalaman tersebut. Kira-kira 90.000 specimen dari 27 species nyamuk telah ditangkap antara bulan Juni 1973 sampai bulan Juli 1974. Penangkapan pada badan binatang dan manusia menghasilkan keterangan-keterangan yang berguna, mengetahui kepadatan musiman dari vektor malaria, Japanese encephalitis dan filaria.A. aconitus adalah satu Anopheline yang terdapat dalam jumlah banyak menggigit manusia dan kepadatan yang tinggi terdapat didaerah pegunungan dimana sawahnya bertingkat-tingkat (terrace). Di Jakarta dan didaerah yang sawahnya datar nyamuk ini praktis tidak diketemukan Puncak kepadatan dari species ini berhubungan dengan musin padi yaitu pada bulan Mei dan Juni, dan pada penangkapan satu malam penuh dengan umpan manusia nyamuk ini terdapat dalam jumlah banyak pada waktu-waktu sebelum tengah malam.Cu. tritaemorrhynchus, Cu. gelidus, Cu. fuscocephalus dan Cu. vishnui menunjukkan kecen­derungan senang terhadap manusia dan babi. Untuk Cu. tritaeniorrhynchus kepadatan dalam jumlah banyak diseluruh kelima daerah penelitian. Puncak kepadatan nyamuk-nyamuk tersebut sangat pendek yaitu beberapa hari sesudah panen. Cu. vishnui lebih senang menggigit manusia bila dibandingkan species lainnya. Di Jakarta terdapat vektor Japanese encephalitis dalam jumlah yang cukup banyak sehingga kemungkinan terjadi penularan didaerah tersebut lebih besar terutama didaerah dimana diketemukan banyak peternakan babu Dua species lainnya yang banyak menggigit manusia adalah Cu. bitaeniorrhynchus dan M. uniformis

    Electron diffraction and high-resolution transmission electron microscopy of the high temperature crystal structures of GexSb2Te3+x (x=1,2,3) phase change material

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    The crystal structures of GeSb2Te4, Ge2Sb2Te5, and Ge3Sb2Te6 were determined using electron diffraction and high-resolution transmission electron microscopy. The structure determined for the former two crystals deviates from the ones proposed in the literature. These crystal structures were developed jointly upon cooling of liquid Ge2Sb2Te5. A stacking disorder parallel to the basal plane was observed that increases with increasing cooling rates. For the GexSb2Te3+x (x=1,2,3) crystals it is shown that an a,b,c stacking holds with an alternating stacking of x GeTe double layers identically present in binary GeTe and one Te-Sb-Te-Te-Sb- repeat unit also present in binary Sb2Te3. A stacking disorder is a logical consequence of building crystals with these two principal units. On the other hand, it is likely that all stable crystals of the Ge-Sb-Te systems are an ordered sequence of these two units. Some of the implications of these findings of the stable and metastable crystal structures that develop from amorphous Ge2Sb2Te5 are presented so as to understand the crucial crystallization process in Ge2Sb2Te5 phase change material

    Popular music, psychogeography, place identity and tourism: The case of Sheffield

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    Tourism and cultural agencies in some English provincial cities are promoting their popular music ‘heritage’ and, in some cases, contemporary musicians through the packaging of trails, sites, ‘iconic’ venues and festivals. This article focuses on Sheffield, a ‘post-industrial’ northern English city which is drawing on its associations with musicians past and present in seeking to attract tourists. This article is based on interviews with, among others, recording artists, promoters, producers and venue managers, along with reflective observational and documentary data. Theoretical remarks are made on the representations of popular musicians through cultural tourism strategies, programmes and products and also on the ways in which musicians convey a ‘psychogeographical’ sense of place in the ‘soundscape’ of the city

    Veterinary students' views on animal patiens and human clients, using Q methodology

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    Veterinarians serve two masters: animal patients and human clients. Both animal patients and human clients have legitimate interests, and conflicting moral claims may flow from these interests. Earlier research concludes that veterinary students are very much aware of the complex and often paradoxical relationship they have and will have with animals. In this article the views of veterinary students about their anticipated relationship with animal patients and human clients are studied. The main part of the article describes discourses of first-year and fourth-year students about their (future) relationship with animals and their caretakers, for which Q-methodology is used. At the end of the article, the discourses are related to the students' gender and their workplace preferences. © 2007 AAVMC

    Aquatic community response to volcanic eruptions on the Ecuadorian Andean flank: evidence from the palaeoecological record

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    Aquatic ecosystems in the tropical Andes are under increasing pressure from human modification of the landscape (deforestation and dams) and climatic change (increase of extreme events and 1.5 °C on average temperatures are projected for AD 2100). However, the resilience of these ecosystems to perturbations is poorly understood. Here we use a multi-proxy palaeoecological approach to assess the response of aquatic ecosystems to a major mechanism for natural disturbance, volcanic ash deposition. Specifically, we present data from two Neotropical lakes located on the eastern Andean flank of Ecuador. Laguna Pindo (1°27.132′S–78°04.847′W) is a tectonically formed closed basin surrounded by a dense mid-elevation forest, whereas Laguna Baños (0°19.328′S–78°09.175′W) is a glacially formed lake with an inflow and outflow in high Andean Páramo grasslands. In each lake we examined the dynamics of chironomids and other aquatic and semi-aquatic organisms to explore the effect of thick (> 5 cm) volcanic deposits on the aquatic communities in these two systems with different catchment features. In both lakes past volcanic ash deposition was evident from four large tephras dated to c.850 cal year BP (Pindo), and 4600, 3600 and 1500 cal year BP (Baños). Examination of the chironomid and aquatic assemblages before and after the ash depositions revealed no shift in composition at Pindo, but a major change at Baños occurred after the last event around 1500 cal year BP. Chironomids at Baños changed from an assemblage dominated by Pseudochironomus and Polypedilum nubifer-type to Cricotopus/Paratrichocladius type-II, and such a dominance lasted for approximately 380 years. We suggest that, despite potential changes in the water chemistry, the major effect on the chironomid community resulted from the thickness of the tephra being deposited, which acted to shallow the water body beyond a depth threshold. Changes in the aquatic flora and fauna at the base of the trophic chain can promote cascade effects that may deteriorate the ecosystem, especially when already influenced by human activities, such as deforestation and dams, which is frequent in the high Andes

    Self-build in the UK and Netherlands:mainstreaming self-development to address housing shortages?

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    This paper examines approaches to self or custom-build in the Netherlands and the UK to offer comparative insights into self- and custom-built housing contexts and cultures, and specifically, the relationships with local and strategic planning arrangements. The paper reviews arguments for self-build as a means to address housing shortages and examines the evidence of completions in practice. It positions the discussion in light of arguments that self-build can become a mainstream source of housing provision. The paper critically considers the role of think tanks in advocating housing policy solutions. Adopting a social constructionist perspective, the paper examines the work of the National Self-Build Association which has devised and implemented an action plan to promote the growth of self-build housing in the UK. Almere, which is located east of Amsterdam, is one of the case studies explored to inform thinking around self-build in the devolved UK. The conclusions tease out some of the implications for democratic and technocratic arguments around self-development and the right to design and build one’s home

    Quantum memories at finite temperature

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    To use quantum systems for technological applications one first needs to preserve their coherence for macroscopic time scales, even at finite temperature. Quantum error correction has made it possible to actively correct errors that affect a quantum memory. An attractive scenario is the construction of passive storage of quantum information with minimal active support. Indeed, passive protection is the basis of robust and scalable classical technology, physically realized in the form of the transistor and the ferromagnetic hard disk. The discovery of an analogous quantum system is a challenging open problem, plagued with a variety of no-go theorems. Several approaches have been devised to overcome these theorems by taking advantage of their loopholes. The state-of-the-art developments in this field are reviewed in an informative and pedagogical way. The main principles of self-correcting quantum memories are given and several milestone examples from the literature of two-, three- and higher-dimensional quantum memories are analyzed

    Adsorption of benzene on Si(100) from first principles

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    Adsorption of benzene on the Si(100) surface is studied from first principles. We find that the most stable configuration is a tetra-σ\sigma-bonded structure characterized by one C-C double bond and four C-Si bonds. A similar structure, obtained by rotating the benzene molecule by 90 degrees, lies slightly higher in energy. However, rather narrow wells on the potential energy surface characterize these adsorption configurations. A benzene molecule impinging on the Si surface is most likely to be adsorbed in one of three different di-σ\sigma-bonded, metastable structures, characterized by two C-Si bonds, and eventually converts into the lowest-energy configurations. These results are consistent with recent experiments.Comment: 4 pages, RevTex, 2 PostScript gzipped figure
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