1,219 research outputs found

    Capturing natural-colour 3D models of insects for species discovery

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    Collections of biological specimens are fundamental to scientific understanding and characterization of natural diversity. This paper presents a system for liberating useful information from physical collections by bringing specimens into the digital domain so they can be more readily shared, analyzed, annotated and compared. It focuses on insects and is strongly motivated by the desire to accelerate and augment current practices in insect taxonomy which predominantly use text, 2D diagrams and images to describe and characterize species. While these traditional kinds of descriptions are informative and useful, they cannot cover insect specimens "from all angles" and precious specimens are still exchanged between researchers and collections for this reason. Furthermore, insects can be complex in structure and pose many challenges to computer vision systems. We present a new prototype for a practical, cost-effective system of off-the-shelf components to acquire natural-colour 3D models of insects from around 3mm to 30mm in length. Colour images are captured from different angles and focal depths using a digital single lens reflex (DSLR) camera rig and two-axis turntable. These 2D images are processed into 3D reconstructions using software based on a visual hull algorithm. The resulting models are compact (around 10 megabytes), afford excellent optical resolution, and can be readily embedded into documents and web pages, as well as viewed on mobile devices. The system is portable, safe, relatively affordable, and complements the sort of volumetric data that can be acquired by computed tomography. This system provides a new way to augment the description and documentation of insect species holotypes, reducing the need to handle or ship specimens. It opens up new opportunities to collect data for research, education, art, entertainment, biodiversity assessment and biosecurity control.Comment: 24 pages, 17 figures, PLOS ONE journa

    Nonequilibrium chiral dynamics by the time dependent variational approach with squeezed states

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    We investigate the inhomogeneous chiral dynamics of the O(4) linear sigma model in 1+1 dimensions using the time dependent variational approach in the space spanned by the squeezed states. We compare two cases, with and without the Gaussian approximation for the Green's functions. We show that mode-mode correlation plays a decisive role in the out-of-equilibrium quantum dynamics of domain formation and squeezing of states.Comment: 5 pages, 4 figures. RevTex, version to appear in Phys. Rev. C. Rapid Communicatio

    Classical Simulation of Quantum Fields II

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    We consider the classical time evolution of a real scalar field in 2 dimensional Minkowski space with a λϕ4\lambda \phi^4 interaction. We compute the spatial and temporal two-point correlation functions and extract the renormalized mass of the interacting theory. We find our results are consistent with the one- and two-loop quantum computation. We also perform Monte Carlo simulations of the quantum theory and conclude that the classical scheme is able to produce more accurate results with a fraction of the CPU time.Comment: 16 pages, 8 figures, now matches published versio

    Wilfred Jones, American Illustrator (1888-1968)

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    Artwork by Wilfed Jones, lent by the artist\u27s daugher, Elizabeth R. Greenhall, November 14th - December 14th, 1977https://digitalcommons.lasalle.edu/exhibition_catalogues/1012/thumbnail.jp

    Research in the general area of non-linear dynamical systems Final report, 8 Jun. 1965 - 8 Jun. 1967

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    Nonlinear dynamical systems research on systems stability, invariance principles, Liapunov functions, and Volterra and functional integral equation

    Analisis terhadap Pemberian Opini Laporan Keuangan Pemerintah Daerah Kabupaten Pegunungan Bintang

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    The purpose of this study is to assess the influence of Internal Control System (SPI) and non-compliance to the opinion of Financial Audit Board (BPK) on Financial Report of Local Governments. We use BPK Audit Reports from 2011 to 2014 from District of Pegunungan Bintang. We analyse the data using descriptive and quantitative analysis. The results show that the type of cases was dominated by the findings of non-compliance with the regulation, as many as 614 cases, then followed by the weakness of SPI that is 184 cases. Non-compliance causes many results for frauds

    Avaliação da depleção linfóide folicular da Bursa de Fabricius: uma metodologia alternativa utilizando análise digital de imagem e redes neurais artificiais

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    Fifty Bursa of Fabricius (BF) were examined by conventional optical microscopy and digital images were acquired and processed using Matlab® 6.5 software. The Artificial Neuronal Network (ANN) was generated using Neuroshell® Classifier software and the optical and digital data were compared. The ANN was able to make a comparable classification of digital and optical scores. The use of ANN was able to classify correctly the majority of the follicles, reaching sensibility and specificity of 89% and 96%, respectively. When the follicles were scored and grouped in a binary fashion the sensibility increased to 90% and obtained the maximum value for the specificity of 92%. These results demonstrate that the use of digital image analysis and ANN is a useful tool for the pathological classification of the BF lymphoid depletion. In addition it provides objective results that allow measuring the dimension of the error in the diagnosis and classification therefore making comparison between databases feasible.Cinquenta Bursa de Fabrícius (BF) foram examinadas através de microscopia óptica convencional e imagens digitais foram obtidas e processadas através do software Matlab® 6.5. Redes Neurais Artificiais (ANN) foram geradas com a utilização do software Neuroshell® Classifier, e os dados das análises óptica e digital foram comparados. A ANN classificou corretamente a maioria dos folículos, atingindo sensibilidade e especificidade de 89% e 96%, respectivamente. Quando os folículos foram agrupados de forma binária houve um aumento da sensibilidade para 90% e obteve-se um valor máximo para a especificidade de 92%. Estes resultados demonstram que o uso da análise digital de imagem associada à ANNé uma ferramenta bastante útil para a classificação patológica da depleção linfóide da BF. Além disso, fornece resultados objetivos que permitem medir a dimensão do erro classificatório, tornando possível a comparação entre distintos bancos de dados

    Matrigel plug assay: evaluation of the angiogenic response by reverse transcription-quantitative PCR

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    The subcutaneous Matrigel plug assay in mice is a method of choice for the in vivo evaluation of pro- and anti-angiogenic molecules. However, quantification of the angiogenic response in the plug remains a problematic task. Here we report a simple, rapid, unbiased and reverse transcription-quantitative PCR (RT-qPCR) method to investigate the angiogenic process occurring in the Matrigel plug in response to fibroblast growth factor-2 (FGF2). To this purpose, a fixed amount of human cells were added to harvested plugs at the end of the in vivo experimentation as an external cell tracer. Then, mRNA levels of the panendothelial cell markers murine CD31 and vascular endothelial-cadherin were measured by species-specific RT-qPCR analysis of the total RNA and data were normalized for human GAPDH or b-actin mRNA levels. RTqPCR was used also to measure the levels of expression in the plug of various angiogenesis/inflammation-related genes. The procedure allows the simultaneous, quantitative evaluation of the newly-formed endothelium and of nonendothelial/ inflammatory components of the cellular infiltrate in the Matrigel implant, as well as the expression of genes involved in the modulation of the angiogenesis process. Also, the method consents the quantitative assessment of the effect of local or systemic administration of anti-angiogenic compounds on the neovascular response triggered by FGF

    An Assessment of Risk of Iodine Deficiency Among Pregnant Women in Sarawak, Malaysia

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    Previous findings from a state-wide Iodine Deficiency Disorders (IDD) study among pregnant women (PW) in Sarawak indicated that PW are at risk of IDD and further assessment is needed. This paper describes the methodology used in conducting this study for an assessment of risk of iodine deficiency among pregnant women in Sarawak, Malaysia. A total of 30 maternal child health care clinics (MCHCs) were selected using probability proportional to population size (PPS) sampling technique. The PW sample size was calculated based on 95% confidence interval (CI), relative precision of 5%, design effect of 2, anticipated IDD prevalence of 65.0% and non-response rate of 20%. Thus, the total sample size required was 750 (25 respondents per selected MCHC). The WHO Expanded Programme on Immunization (EPI) surveys approach was used to randomly select the first respondent and subsequent respondents were chosen until the required number of PW was met. The required data were obtained through: face-to-face interviews (socio-demographic and food frequency questionnaire), clinical assessments (thyroid size, and hyper/hypothyroidism) and biochemical analysis (urine and blood serum). A total of 677 PW responded in the study with a response rate of 90.2%. Majority of the PW were at second gravida, aged 25-29 years old and of Malay ethnicity. The methodology used in this study was based on International guidelines which may provide state's estimates. All the necessary steps were taken into consideration to ensure valid and reliable findings on current iodine status among PW
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