195 research outputs found

    Quantifying the interdisciplinarity of scientific journals and fields

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    There is an overall perception of increased interdisciplinarity in science, but this is difficult to confirm quantitatively owing to the lack of adequate methods to evaluate subjective phenomena. This is no different from the difficulties in establishing quantitative relationships in human and social sciences. In this paper we quantified the interdisciplinarity of scientific journals and science fields by using an entropy measurement based on the diversity of the subject categories of journals citing a specific journal. The methodology consisted in building citation networks using the Journal Citation Reports database, in which the nodes were journals and edges were established based on citations among journals. The overall network for the 11-year period (1999-2009) studied was small-world and scale free with regard to the in-strength. Upon visualizing the network topology an overall structure of the various science fields could be inferred, especially their interconnections. We confirmed quantitatively that science fields are becoming increasingly interdisciplinary, with the degree of interdisplinarity (i.e. entropy) correlating strongly with the in-strength of journals and with the impact factor.Comment: 23 pages, 6 figure

    Environment Influence On Pspl-based Digital Dental Radiology Systems

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    Photo-stimulable phosphor luminescence technology (PSPL) has been used in Digora (Soredex, Finland) and Denoptix (CEDH Gendex, Italy) digital dental radiology imaging systems. PSPL plates store X-ray energy during exposition, being later processed by a laser reader and digitizer. Afterward they are erased and re-used. The large band of energy absorption provides PSPL systems with an extensive dynamic scale but at the same time a high sensibility to the incoming noise of environmental radiations. We have measured environment influences (electromagnetic radiation) for Digora and Denoptix plates after X-ray exposure and before digital processing. We have first compared the processing of PSPL plates "in dark" against "in light" environments. In another experiment, the exposed plates were also processed after being positioned 10 cm away from a 17 inches video monitor screen and to its laterals for 5, 10, 15, 20, 25 and 30 minutes (plates protected against light). The acquired images were used to calculate the noise power spectra (NPS) in each case. We have noticed that there was an increase in the noise spectra energy of "in light" processing compared to "in dark" processing. There was also an increment in the NPS energy when the images were processed after the exposition of the plates to the radiation emanated from video monitor.4320219226Huda, W., Comparison of a photostimulable phosphor system with film for dental radiology (1997) Oral Surgery Oral Medicine Oral Pathology, 84, pp. 725-731Brettle, D.S., The imaging performance of a storage phosphor system for dental radiography (1996) The British Journal of Radiology, 69, pp. 256-261Xinhua, A novel algorithm for measuring the MTF of a digital radiographic system with a CCD array detector (2000) SPIE, 3977, pp. 580-587Knüpfer, W., Novel X-ray detectors for medical imaging (1999) Nuclear Physics, 78, pp. 610-615Hildebold, C.F., Dental photostimulable phosphor radiology (2000) Dental Clinics of North America, 44 (2), pp. 273-297Stamatakis, Dose response of a storage phosphor system for intraoral radiography (1999) Dentomaxillofacial Radiology, 28, pp. 272-276Yoshiura, K., Physical evaluation of a system for direct digital intra-oral radiography based on a charged-coupled device (1999) Dentomaxillofacial Radiology, 28, pp. 277-283Workman, A., Brettle, D.S., Physical performance measures of radiographic imaging systems (1997) Dentomaxillofacial Radiology, 26, pp. 139-146Granfors, P.R., Performance characteristics of an amorphous silicon flat panel X-ray imaging detector (1999) SPIE, 3659, pp. 480-490Yoshiura, K., Physical evaluation of a system for direct digital intra-oral radiography based on a charged-coupled device (1999) Dentomaxillofacial Radiology, 28, pp. 277-283Kengyelics, S.M., Image quality evaluation of a direct digital radiology detector operating in a UK radiology department (1999) SPIE, 3659, pp. 24-35Granfords, P.R., Aufrichtig, P.R.R., DQE(f) of an amorphous silicon flat panel X-ray detector: Detector parameter influences and measurement methodology (2000) SPIE, 3977, pp. 2-13Dobbins III, J.T., DQE(f) of four generations of computed radiography devices (1995) Medical Physics, 22, pp. 1581-1593Cowen, A.R., Workman, A., A physical image quality evaluation of a digital spot flurography system (1992) Phys. Med. Biol., 37, pp. 325-342Daint, J.C., Shaw, R., (1976) Image Science - Principles, Analyses and Evaluation of Photographic-Type Imaging Process, , Academic Press, London, UKBethea, R.M., Duran, B.S., Benllion, T.L., (1995) Statistical Methods for Engineers and Scientists, , Mc Hill Reckker, New York, NYZanella, G., Zannoni, R., DQE of imaging detectors in terms of spatial frequency (1999) Nuclear Instruments and Methods Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 437, pp. 163-167Zanella, G., Zannoni, R., The role of the quantum efficiency on the DQE of an imaging detector (1996) Nuclear Instruments and Methods in Physics Research A, 381, pp. 157-160Costa, S., DQE measurement in a scintillating glass optical fiber detector for X-ray imaging (1996) Nuclear Instruments and Methods in Physics Research A, 380, pp. 568-571Meyer, R.R., Experimental characterization of CCD cameras for HREM at 300kV (2000) Ultramicroscopy, 85, pp. 9-13Onttonello, P., MTF and DQE measurement in imaging detectors by their single-event response (1998) Nuclear Instruments and Methods in Physics Research Section A, 419, pp. 731-735Kandarakis, I., An experimental method for the determination of spatial-frequency-dependent detective quantum efficiency (DQE) of scintillators used in X-ray imaging detectors (1997) Nuclear Instruments and Methods in Physics Research Section A, 399, pp. 335-34

    Evaluation Of Pspl Plate Erasing Time Of A Digital Dental Radiology System

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    Denoptix (CEDH Gendex Dental System, Milan, Italy) dental imaging system uses photo-stimulable phosphor luminescence (PSPL) plates to store energy during X-ray exposure, being later processed by a laser reader and digitizer. Afterwards the plate is erased and re-used. The cleaning process described by the manufacturer consists of exposing the PSPL plates to negatoscope light for 5 minutes. Proper light intensity and exact erasing time must be considered in order to guarantee good quality procedures in its re-utilization. X-ray exposed plates were submitted to four negatoscopes with different measured light intensities for several periods of light exposure, until the Denoptix system was unable to process the latent image in the plates, and we considered then that the plates were cleaned. We have found the relationships between erasing time, exposed dose and negatoscope light intensity. We have also measured the relative plate image fading with negatoscope light exposure time. We have concluded that a Poisson process governs plate erasing. Considering clinical situations, we have shown that it was possible to largely reduce erasing time and increase plate re-utilization. The exponential decay of image data also suggested a still smaller erasing time, representative of a partial cleaning status assuming that residual noise presence in the erased plate is clinically acceptable.4320227235Janhom, A., Effect of noise on the compressibility and diagnostic accuracy for caries detection of digital bitewing radiographs (1999) Dentomaxillofacial Radiology, 28, pp. 6-12Huda, W., Comparison of a photo-stimulable phosphor system with film for dental radiology (1997) Oral Surgery Oral Medicine Oral Pathology, 84, pp. 725-731Brettle, D.S., The imaging performance of a storage phosphor system for dental radiography (1996) The British Journal of Radiology, 69, pp. 256-261Yoshiura, K., Physical evaluation of a system for direct digital intra-oral radiography based on a charged-coupled device (1999) Dentomaxillofacial Radiology, 28, pp. 277-283Xinhua, A novel algorithm for measuring the MTF of a digital radiographic system with a CCD array detector (2000) SPIE, 3977, pp. 580-587Hildebold, C.F., Dental photostimulable phosphor radiology (2000) Dental Clinics of North America, 44 (2), pp. 273-297(1998) Denoptix System User Manual, , CEDH Gendex Dental System, Milan, ItalyBethea, R.M., Duran, B.S., Benllion, T.L., (1995) Statistical Methods for Engineers and Scientists, , Mc Hill Reckker, New York, NYWebb, S., (1995) The Physics of Medical Imaging, , Institute of Physis Publishing, Bristol, UK(1996) Mathematics and Physics of Emerging Biomedical Imaging, , National Research Council, Institute of Medicine, National Academy Press, Washington D.CBarret, H., Harrison, H., Swindell, W., (1981) Radiological Imaging: The Theory of Image Formation, Detection and Processing, 1-2. , Academic Press, London, UKDaint, J.C., Shaw, R., (1976) Image Science - Principles, Analyses and Evaluation of Photographic-Type Imaging Process, , Academic Press, London, U

    Vascular Flora Of The Legado Das Águas, Reserva Votorantim, Municipalities Of Tapiraí, Miracatú And Juquiá, São Paulo, Brazil

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We present a list of vascular plants found in Legado das Águas, Reserva Votorantim, a private reserve having an area of approximately 35,000 ha that spans the municipalities of Tapiraí, Miracatú, and Juquiá, in the state of São Paulo, Brazil. The reserve is part of a complex of state-protected areas including Alto Ribeira Touristic State Park, Intervales State Park, Carlos Botelho State Park, Jurupará State Park, and Serra do Mar State Park. Together, these form an important and large area of continuous and well-preserved forest. Our study, which involved two main floristic surveys in March/April 2013 and April 2014, recorded 768 species, representing 131 families and 432 genera. The majority of species were angiosperms (619) representing 106 families and 370 genera. There were also two species of gymnosperms belonging to two genera in separate families; 147 species of ferns and lycophytes belonging to 23 families and 60 genera. In demonstrating the presence of almost 800 species of plants, of which 16 are threatened, our study highlights the importance of floristic surveys and the critical role of private protected areas in managing and preserving native flora. © 2016 Check List and Authors.1262011/22923-8, FAPESP, Fundação de Amparo à Pesquisa do Estado de São Paulo2015/9444-4, FAPESP, Fundação de Amparo à Pesquisa do Estado de São PauloFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
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