252 research outputs found
A non-additive repulsive contribution in an equation of state: The development for homonuclear square well chains equation of state validated against Monte Carlo simulation
Full text linkInternational audienceThis work consists of the adaptation of a non-additive hard sphere theory inspired by Malakhov and Volkov, Polym. Sci. Ser. A. 2007;49(6):745-756 to a square-well chain. Using the thermodynamic perturbation theory, an additional term is proposed that describes the effect of perturbing the chain of square well spheres by a non-additive parameter. In order to validate this development, NPT Monte Carlo simulations of thermodynamic and structural properties of the non-additive square well (NASW) for a pure chain and a binary mixture of chains are performed. Good agreements are observed between the compressibility factor originating from the theory and those from molecular simulations
An Efficient, Highly Flexible Multi-Channel Digital Downconverter Architecture
Get PDFIn this innovation, a digital downconverter has been created that produces a large (16 or greater) number of output channels of smaller bandwidths. Additionally, this design has the flexibility to tune each channel independently to anywhere in the input bandwidth to cover a wide range of output bandwidths (from 32 MHz down to 1 kHz). Both the flexibility in channel frequency selection and the more than four orders of magnitude range in output bandwidths (decimation rates from 32 to 640,000) presented significant challenges to be solved. The solution involved breaking the digital downconversion process into a two-stage process. The first stage is a 2 oversampled filter bank that divides the whole input bandwidth as a real input signal into seven overlapping, contiguous channels represented with complex samples. Using the symmetry of the sine and cosine functions in a similar way to that of an FFT (fast Fourier transform), this downconversion is very efficient and gives seven channels fixed in frequency. An arbitrary number of smaller bandwidth channels can be formed from second-stage downconverters placed after the first stage of downconversion. Because of the overlapping of the first stage, there is no gap in coverage of the entire input bandwidth. The input to any of the second-stage downconverting channels has a multiplexer that chooses one of the seven wideband channels from the first stage. These second-stage downconverters take up fewer resources because they operate at lower bandwidths than doing the entire downconversion process from the input bandwidth for each independent channel. These second-stage downconverters are each independent with fine frequency control tuning, providing extreme flexibility in positioning the center frequency of a downconverted channel. Finally, these second-stage downconverters have flexible decimation factors over four orders of magnitude The algorithm was developed to run in an FPGA (field programmable gate array) at input data sampling rates of up to 1,280 MHz. The current implementation takes a 1,280-MHz real input, and first breaks it up into seven 160-MHz complex channels, each spaced 80 MHz apart. The eighth channel at baseband was not required for this implementation, and led to more optimization. Afterwards, 16 second stage narrow band channels with independently tunable center frequencies and bandwidth settings are implemented A future implementation in a larger Xilinx FPGA will hold up to 32 independent second-stage channels
Concert recording 2017-12-01
Get PDF[Tracks 1-15]. 15 etudes op. 76(a) / David Popper -- [Track 16]. Suite no. 1, BWV 1007. Prelude [Track 17]. Sarabande [Track 18]. Minuet. / Johann Sebastian Bach -- [Track 19]. Suite no. 2, BWV 1008. Prelude [Track 20]. Gigue [Track 21]. Allemande [Track 22]. Courante [Track 23]. Sarabande [Track 24]. Minuet. / Johann Sebastian Bach -- [Track 25]. Suite no. 3, BWV 1009. Prelude [Track 26]. Allemande [Track 27]. Courante [Track 28]. Bourreé [Track 29]. Sarabande [Track 30]. Gigue / Johann Sebastian Bach -- [Track 31]. Suite no. 1, BWV 1007.Prelude [Track 32]. Courante [Track 33]. Sarabande / Johann Sebastian Bach -- [Track 34] Suite No. 4, BWV 1010. Prelude [Track 35]. Sarabande / Johann Sebastian Bach -- [Track 36]. Sicilienne / Maria Theresia von Paradis arranged by Dominic K Na -- [Track 37]. Ständchen / Franz Schubert arranged by Dominic K Na -- [Track 38]. The ragtime dance / Scott Joplin arranged by Dominic K Na
Two Probable Cases of Infection with Treponema pallidum during the Neolithic Period in Northern Vietnam (~2000-1500B.C.)
Get PDFWe would like to thank Dr. Ngo Anh Son, Mr. Bui Van Khanh, and Ms. Nellissa Ling for their assistance with the radiographs, and Dr. Anne Marie E. Snoddy for in-put on the application of a standardized approach to treponemal disease. We thank the associate editor of Bioarchaeology International and three anonymous reviewers for their comments and advice in revising the manuscript. Funding: This research was supported by a National Geographic Early Career Grant (EC-54332R-18), Royal Society of New Zealand Skinner Fund Grant and a University of Otago Doctoral Scholarship.Peer reviewedPostprin
Two probable cases of infection with Treponema pallidum during the Neolithic period in Northern Vietnam (~2000- 1500B.C.)
Get PDFSkeletal evidence of two probable cases of treponematosis, caused by infection with the bacterium Treponema pallidum, from the northern Vietnamese early Neolithic site of Man Bac (1906–1523 cal B.C.) is described. The presence of nodes of subperiosteal new bone directly associated with superfcial focal cavitations in a young adult male and a seven- year- old child are strongly diagnostic for treponemal disease. Climatic and epidemiological contexts suggest yaws (Treponema pallidum pertenue) as the most likely causative treponeme. This evidence is the oldest discovered in the Asia- Pacific region and is the first well- established pre-Columbian example in this region in terms of diagnosis and secure dating. The coastal ecology, sedentary settlement, and high fertility at the site of Man Bac all provided a biosocial context conducive to the spread of treponemal disease among inhabitants of the site. Co- morbidity with scurvy in both individuals demonstrates that malnutrition during the agricultural transition may have exacerbated the expression of treponematosis in this community.
Man Bac is a site of great regional importance owing to its role during the Neolithic transition of Mainland Southeast Asia. During this transition, approximately 4,000 years ago, farmers migrating from southern China into Southeast Asia influenced a number of changes in subsistence and demography and potentially introduced new infectious diseases such as treponematosis to indigenous forager communities. The findings presented here may encourage reevaluation of existing Southeast Asian skeletal samples and demonstrate the importance of using weighted diagnostic criteria for future reporting of treponematosis cases
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