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81.
BACKGROUND: Conditions once considered bad habits are now recognized as psychiatric disorders (trichotillomania, onychopagia). We hypothesized that nose picking is another such "habit," a common benign practice in most adults but a time-consuming, socially compromising, or physically harmful condition (rhinotillexomania) in some. METHODS: We developed the Rhinotillexomania Questionnaire, mailed it to 1000 randomly selected adult residents of Dane County, Wisconsin, and requested anonymous responses. The returned questionnaires were analyzed according to age, sex, marital status, living arrangement, and educational level. Nose picking was characterized according to time involved, level of distress, location, attitudes toward self and others regarding the practice, technique, methods of disposal, reasons, complications, and associated habits and psychiatric disorders. RESULTS: Two hundred fifty-four subjects responded. Ninety-one percent were current nose pickers although only 75% felt "almost everyone does it"; 1.2% picked at least every hour. For 2 subjects (0.8%), nose picking caused moderate to marked interferences with daily functioning. Two subjects spent between 15 and 30 minutes and 1 over 2 hours a day picking their nose. For 2 others, perforation of the nasal septum was a complication. Associated "habits" included picking cuticles (25%), picking at skin (20%), biting fingernails (18%), and pulling out hair (6%). CONCLUSION: This first population survey of nose picking suggests that it is an almost universal practice in adults but one that should not be considered pathologic for most. For some, however, the condition may meet criteria for a disorder-rhinotillexomania. 相似文献
82.
Bernal MP Coufal H Grygier RK Hoffnagle JA Jefferson CM Macfarlane RM Shelby RM Sincerbox GT Wimmer P Wittmann G 《Applied optics》1996,35(14):2360-2374
The design and the realization of an advanced precision optical test stand for evaluating materials and developing tools and techniques for holographic digital data storage are described. This apparatus allows studies of holographic recording materials and recording physics to be performed in the context of practical data storage. The system concept, its implementation, and its performance are described, and examples of holographic storage in photorefractive materials are discussed. 相似文献
83.
Will Usher Ingo Wald Jefferson Amstutz Johannes Günther Carson Brownlee Valerio Pascucci 《Computer Graphics Forum》2019,38(3):455-466
Image‐ and data‐parallel rendering across multiple nodes on high‐performance computing systems is widely used in visualization to provide higher frame rates, support large data sets, and render data in situ. Specifically for in situ visualization, reducing bottlenecks incurred by the visualization and compositing is of key concern to reduce the overall simulation runtime. Moreover, prior algorithms have been designed to support either image‐ or data‐parallel rendering and impose restrictions on the data distribution, requiring different implementations for each configuration. In this paper, we introduce the Distributed FrameBuffer, an asynchronous image‐processing framework for multi‐node rendering. We demonstrate that our approach achieves performance superior to the state of the art for common use cases, while providing the flexibility to support a wide range of parallel rendering algorithms and data distributions. By building on this framework, we extend the open‐source ray tracing library OSPRay with a data‐distributed API, enabling its use in data‐distributed and in situ visualization applications. 相似文献
84.
Araújo José Denes Lima Souza Johnatan Carvalho Neto Otilio Paulo Silva de Sousa Jefferson Alves de Almeida João Dallyson Sousa de Paiva Anselmo Cardoso Silva Aristófanes Corrêa Junior Geraldo Braz Gattass Marcelo 《Multimedia Tools and Applications》2019,78(10):12987-13004
Multimedia Tools and Applications - Glaucoma is the second major cause of vision loss worldwide. It is usually caused by the increase in the intraocular pressure, which damages the optic nerve... 相似文献
85.
Rodolpho M. de Andrade Jefferson S. de Gois Isabela Maia Toaldo Diego Barros Batista Aderval S. Luna Daniel L. G. Borges 《Food Analytical Methods》2017,10(5):1209-1215
This work presents a direct and straightforward approach for the determination of trace elements in fish muscle, oyster, and bovine liver via direct solid sample analysis (SS) using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS). The preliminary studies revealed the presence of spectral interferences at the analytical line of Ni at 231.096 nm, which could be corrected subtracting the spectrum of SiO and PO from the sample spectra using least-squares background correction. Moreover, all meat samples were proven homogeneous according to the homogeneity factor (H e) (all values were <10 mg½). Pyrolysis (Tp) and atomization (Ta) temperatures were studied and optimized as 800 °C (Tp) and 2500 °C (Ta) for Mn, 700 °C (Tp) and 2600 °C (Ta) for Ni, and 600 °C (Tp) and 2500 °C (Ta) for Rb. Calibration against aqueous standards was proven feasible for Mn determination, whereas Ni and Rb required calibration against solid standards for their quantification. The detection limits achieved were demonstrated adequate for application to food analysis (0.005 μg g?1 for Mn, 0.002 μg g?1 for Ni, and 0.1 μg g?1 for Rb). The developed method was successfully applied for the elemental analysis of fish muscle, oyster, and bovine liver and three certified reference materials, demonstrating good agreement with the certified values and with the reference technique at a 95 % statistical confidence level. 相似文献
86.
A. E. Bailey M. E. Jefferson Florence B. Kreeger S. T. Bauer 《Journal of the American Oil Chemists' Society》1945,22(1):10-13
Summary 1. Melting points and x-ray diffraction patterns have been determined for cottonseed oil hydrogenated to an iodine value of
less than 1, and for a very pure sample of tristearin.
2. Contrary to the observations of previous investigators, the x-ray patterns indicate a well-defined crystal structure with
a sharp long spacing and a single sharp short spacing in the lowest-melting form of tristearin. A new pattern, with two short
spacings and a long spacing, was observed in tristearin of intermediate melting point.
3. Four polymorphic forms of the hydrogenated cottonseed oil were detected. The x-ray pattern of the lowest-melting form of
the hydrogenated oil was similar to that of the correspopnding form of tristearin. The pattern of the highest-melting form
of the hydrogenated oil differed from that of either tristearin or β-palmitodistearin, the major components of the oil. Distinctive
patterns for the intermediate forms of the hydrogenated oil could not be obtained, presumably because of the instability of
the lower melting forms at room temperature.
One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S.
Department of Agriculture. 相似文献
87.
Marcelo Vasconcelos de Carvalho Davi Melo Montenegro Jefferson de Oliveira Gomes 《Journal of Materials Processing Technology》2013,213(4):560-573
The main goal of this work is to perform an analysis of the machinability of two ASTM grades of ADI, namely 2 and 3. The samples used in this work were cast and austempered according to ASTM standards for the production of grade 2 (G2) and grade 3 (G3) ADI. Characterization was accomplished through tensile and hardness tests, metallography and X-ray diffraction. Machinability was evaluated by analyzing tool life, cutting forces, surface finish and chip characteristics in turning operations. A quick-stop test was also performed in order to verify some mechanical processes during the chip formation and to analyze the shear plane angle. Tool life when machining G2 was 33% lower than G3 (18 min against 26 min), although the latter is a harder material. Abrasion and adhesion were the wear mechanisms observed through SEM images, whereas in other cast irons mainly abrasion is observed. Cutting forces measurements showed that the value of Kc1,1 decreased 19%, from 1448 to 1175 N/mm2, for G2 as the depth of cut increased from 2 to 5 mm at a cutting speed of 80 m/min and 18%, from 1501 to 1236 N/mm2, for G3. Surface roughness measurements proved that a smoother surface is obtained for both alloys at f = 0.10 mm/rev when using an insert with nose radius 1.6 mm instead of smaller radii. Both alloys presented similar surface quality. All chips observed were segmented. 相似文献
88.
Rita Henderson Michael Chips Neill Cornwell Philip Hitchins Barrie Holden Steve Hurley Simon A. Parsons rew Wetherill & Bruce Jefferson 《Water and Environment Journal》2008,22(3):184-192
Algae blooms are a seasonal problem in UK waters and during these periods interferences with treatment plants are reported. This paper presents an analysis of data from 2000 to 2005 demonstrating UK experiences of algae at water treatment works. Cell populations are lower than those reported in the 1970s and 1980s, but reach levels that adversely affect treatment processes. Diatoms and cyanobacteria dominate in spring and autumn respectively. A treatment works including pre-oxidation, coagulation, flotation and filtration removes on average 96% of influent cells, while rapid gravity filters alone remove 63–75%. Cells present in the filtrate are typically either unicellular, micro-algae, or flagellated algae. filter blockages in the spring and autumn are caused by large cells of complex morphology, including the diatoms Melosira and Asterionella . Overall, since the 1980s the key issue with respect to algae treatment has changed from one of treatability to that of process optimisation and economics. 相似文献
89.
Moreno Paalo Villamizar Nicole Perez Jefferson Bayona Angelica Roman Jesús Moreno Nicolás Cardozo Nilo Sergio Medeiros 《Clean Technologies and Environmental Policy》2021,23(5):1537-1546
Clean Technologies and Environmental Policy - Housing construction consumes more materials than any other economic activity, with a total of 40.6 Gt/year. Boards are placed between... 相似文献
90.
This paper presents details of an original crack-closure system for cementitious materials using shrinkable polymer tendons. The system involves the incorporation of unbonded pre-oriented polymer tendons in cementitious beams. Crack closure is achieved by thermally activating the shrinkage mechanism of the restrained polymer tendons after the cement-based material has undergone initial curing.The feasibility of the system is demonstrated in a series of small scale experiments on pre-cracked prismatic mortar specimens. The results from these tests show that, upon activation, the polymer tendon completely closes the preformed macro-cracks and imparts a significant stress across the crack faces.The potential of the system to enhance the natural autogenous crack healing process and generally improve the durability of concrete structures is addressed. 相似文献