1,199 research outputs found

    Use of fractal dimensions to quantify coral shape

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    A morphometrical method to quantify and characterize coral corallites using Richardson Plots and Kaye's notion of fractal dimensions is presented. A Jurassic coral species (Aplosmilia spinosa) and five Recent coral species were compared using the Box-Counting Method. This method enables the characterization of their morphologies at calicular and septal levels by their fractal dimensions (structural and textural). Moreover, it is possible to determine differences between species of Montastraea and to tackle the high phenotypic plasticity of Montastraea annularis. The use of fractal dimensions versus conventional methods (e.g., measurements of linear dimensions with a calliper, landmarks, Fourier analyses) to explore a rugged boundary object is discussed. It appears that fractal methods have the potential to considerably simplify the morphometrical and statistical approaches, and be a valuable addition to methods based on Euclidian geometr

    Brucellosis in terrestrial wildlife

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    The epidemiological link between brucellosis in wildlife and brucellosis in livestock and people is widely recognised. When studying brucellosis in wildlife, three questions arise: (i) Is this the result of a spillover from livestock or a sustainable infection in one or more host species of wildlife? (ii) Does wildlife brucellosis represent a reservoir of Brucella strains for livestock? (iii) Is it of zoonotic concern? Despite their different host preferences, B. abortus and B. suis have been isolated from a variety of wildlife species, whereas B. melitensis is rarely reported in wildlife. The pathogenesis of Brucella spp. in wildlife reservoirs is not yet fully defi ned. The prevalence of brucellosis in some wildlife species is very low and thus the behaviour of individual animals, and interactions between wildlife and livestock, may be the most important drivers for transmission. Since signs of the disease are non-pathognomonic, defi nitive diagnosis depends on laboratory testing, including indirect tests that can be applied to blood or milk, as well as direct tests (classical bacteriology and methods based on the polymerase chain reaction [PCR]). However, serological tests cannot determine which Brucella species has induced anti-Brucella antibodies in the host. Only the isolation of Brucella spp. (or specifi c DNA detection by PCR) allows a defi nitive diagnosis, using classical or molecular techniques to identify and type specifi c strains. There is as yet no brucellosis vaccine that demonstrates satisfactory safety and effi cacy in wildlife. Therefore, controlling brucellosis in wildlife should be based on good management practices. At present, transmission of Brucella spp. from wildlife to humans seems to be linked to the butchering of meat and dressing of infected wild or feral pig carcasses in the developed world, and infected African buffalo in the developing world. In the Arctic, the traditional consumption of raw bone marrow and the internal organs of freshly killed caribou or reindeer is an important risk factor.bacteriologyBrucella sppBrucellosisEpidemiologyLivestock/wildlife interfaceSerologyWildlifePublishe

    Low-temperature specific heat of real crystals: Possibility of leading contribution of optical and short-wavelength acoustical vibrations

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    We point out that the repeatedly reported glass-like properties of crystalline materials are not necessarily associated with localized (or quasilocalized) excitations. In real crystals, optical and short-wavelength acoustical vibrations remain damped due to defects down to zero temperature. If such a damping is frequency-independent, e.g. due to planar defects or charged defects, these optical and short-wavelength acoustical vibrations yield a linear-in-TT contribution to the low-temperature specific heat of the crystal lattices. At low enough temperatures such a contribution will prevail over that of the long-wavelength acoustical vibrations (Debye contribution). The crossover between the linear and the Debye regime takes place at TNT^* \propto \sqrt N, where NN is the concentration of the defects responsible for the damping. Estimates show that this crossover could be observable.Comment: 5 pages. v4: Error in Appendix corrected, which does not change the main results of the pape

    Analisis Faktor Penurunan Tanah Terhadap Kinerja Automated Rubber Tyred Gantry Pada Terminal Peti Kemas Semarang

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    Penurunan tanah yang terjadi di Terminal Peti Kemas Semarang, khususnya pada Container Yard 05 tempat Automated Rubber Tyred Gantry beroperasi menyebabkan sistem operasi ARTG terganggu. Hal tersebut dikarenakan penurunan tanah menyebabkan kemiringan pada ARTG pad. Tujuan yang ingin dicapai dalam penulisan tugas akhir ini adalah untuk memprediksi kapan kemiringan ARTG pad pada tiap blok melewati batas toleransi supaya segera dilakukan tindakan untuk mengatasi masalah tersebut. Berdasarkan perhitungan konsolidasi, penurunan tanah pada Container Yard 05 seharusnya berhenti pada 300 sampai 360 hari setelah pekerjaan reklamasi selesai. Namun saat dilakukan pengukuran lapangan di bulan Agustus 2016 dan Maret 2017 masih terdapat penurunan tanah. Berdasarkan data pengukuran lapangan yang ada, dilakukan pendekatan berupa persamaan linear untuk memprediksi kapan masing-masing blok pelayanan ARTG sistemnya terganggu. Diprediksi Blok C akan terganggu sistemnya paling awal, yaitu pada bulan Maret 2017. Blok D akan terganggu sistemnya pada September 2017, kemudian pada bulan Februari 2018, Blok F sistemnya terganggu. Sistem Blok G akan terganggu di bulan April 2018, sedangkan sistem pada blok E diprediksi akan terganggu paling akhir yaitu bulan Juni 2019. Saran yang dapat diberikan ialah saat proses reklamasi, sebelum area reklamasi diberikan perkerasan, derajat konsolidasinya sudah harus mencapai atau mendekati 90%. Dengan demikian tanah yang ditimbun akan lebih stabil saat mulai diberikan beban operasional. Untuk blok yang sistemnya akan terganggu, dapat dilakukan pekerjaan leveling

    Impact of multimorbidity on disability and quality of life in the Spanish older population

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    Background Population aging is closely related to high prevalence of chronic conditions in developed countries. In this context, health care policies aim to increase life span cost-effectively while maintaining quality of life and functional ability. There is still, however, a need for further understanding of how chronic conditions affect these health aspects. The aim of this paper is to assess the individual and combined impact of chronic physical and mental conditions on quality of life and disability in Spain, and secondly to show gender trends. Methods Cross-sectional data were collected from the COURAGE study. A total of 3,625 participants over 50 years old from Spain were included. Crude and adjusted multiple linear regressions were conducted to detect associations between individual chronic conditions and disability, and between chronic conditions and quality of life. Separate models were used to assess the influence of the number of diseases on the same variables. Additional analogous regressions were performed for males and females. Results All chronic conditions except hypertension were statistically associated with poor results in quality of life and disability. Depression, anxiety and stroke were found to have the greatest impact on outcomes. The number of chronic conditions was associated with substantially lower quality of life [ß for 4+ diseases: -18.10 (-20.95,-15.25)] and greater disability [ß for 4+ diseases: 27.64 (24.99,30.29]. In general, women suffered from higher rates of multimorbidity and poorer results in quality of life and disability. Conclusions Chronic conditions impact greatly on quality of life and disability in the older Spanish population, especially when co-occurring diseases are added. Multimorbidity considerations should be a priority in the development of future health policies focused on quality of life and disability. Further studies would benefit from an expanded selection of diseases. Policies should also deal with gender idiosyncrasy in certain cases
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