247 research outputs found

    Development of a Real-Time, Simple and High-Accuracy Fall Detection System for Elderly Using 3-DOF Accelerometers

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    © 2018, King Fahd University of Petroleum & Minerals. Falls represent a major problem for the elderly people aged 60 or above. There are many monitoring systems which are currently available to detect the fall. However, there is a great need to propose a system which is of optimal effectiveness. In this paper, we propose to develop a low-cost fall detection system to precisely detect an event when an elderly person accidentally falls. The fall detection algorithm compares the acceleration with lower fall threshold and upper fall threshold values to accurately detect a fall event. The post-fall recognition module is the combination of posture recognition and vertical velocity estimation that has been added to our proposed method to enhance the performance and accuracy. In case of a fall, our device will transmit the location information to the contacts instantly via SMS and voice call. A smartphone application will ensure that the notifications are delivered to the elderly person’s relatives so that medical attention can be provided with minimal delay. The system was tested by volunteers and achieved 100% sensitivity and accuracy. This was confirmed by testing with public datasets and it also achieved the same percentage in sensitivity and accuracy as in our recorded datasets

    Seasonal variation of phytoplankton in My Thanh River, Mekong delta, Vietnam

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    A study on the seasonal variation of phytoplankton composition was conducted at the upper, middle, and lower parts of the My Thanh River, which supplies an important source of water for aquaculture. Qualitative and quantitative samples of phytoplankton were collected monthly at both high and low tide. The results showed that a total of 171 phytoplankton (algae) species were recorded, belonging to 59 genera and 5 phyla. Diatoms were the most abundant group with the highest species number, followed by green algae. The other phyla possessed a lower number of species. The species composition was more diverse in the rainy season and at high tide at most of the sampling sites. The mean density of algae varied from 30,900-43,521 ind.L^-1^. The density of diatoms was higher in the middle and lower parts. At the same time, euglenoids displayed the highest density in the upper part, showing a difference in the dominant algae group under the influence of salinity. Salinity was found to be significantly positively correlated (p<0.01) with diatoms, whereas it was negatively correlated (p<0.05) with blue-green algae and euglenoids. The algae composition was quite diverse, with the H' index ranging from 2.0-3.3, showing the water quality was slightly to moderately polluted

    Solar models and solar neutrino oscillations

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    We provide a summary of the current knowledge, theoretical and experimental, of solar neutrino fluxes and of the masses and mixing angles that characterize solar neutrino oscillations. We also summarize the principal reasons for doing new solar neutrino experiments and what we think may be learned from the future measurements.Comment: Submitted to the Neutrino Focus Issue of New Journal of Physics at http://www.njp.or

    Is there a problem with low energy SN1987A neutrinos?

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    (abridged) We study the low energy events observed by Kamiokande-II. We focus on the event 6 of 6.3 MeV and also on the other events that at 1 sigma fall below the energy threshold: events 3,4,10,12. The volume distribution is not a uniform distribution at 3 sigma, that suggests the presence of background events close or at the border of the volume used for the analysis, including the events 3,4,10. We checked the expected energy distribution assuming that the signal is due to nubar(e)p-->e+n and that the average antineutrino energy is 14 MeV. The agreement with the observations is not perfect but it is acceptable at the 11 % confidence level if we include the peak of low energy background events; otherwise, we face a 2.9 sigma problem. The expected energy distribution implies that the evidence for supernova neutrinos is at 10 sigma and that 1-3 background events are plausible. This conclusion does not change strongly when we model the time distribution of the signal taking into account the presence of an initial luminous phase of neutrino emission. This suggests however that some of the early events are due to supernova neutrinos and not to background. In summary, we formulate the hypothesis that some of the observed low energy events are due to background and that some among them belong to a peculiar phase of emission, that could be further characterized by low energy neutrinos. Such an interpretation diminishes to a minimum the postulated number of background events and thus improves the agreement between the a priori and the a posteriori expectations on the number of background events. We argue on these grounds that there is no significant disagreement between the average energy of the supernova neutrinos seen in Kamiokande-II and the conventional expectations.Comment: 28 pages, 4 figures. V3: relevance of the time distribution for the interpretation of low energy events and improved analysis of backgroun

    Respiratory viruses in individuals with a high frequency of animal exposure in southern and highland Vietnam

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    Active surveillance for zoonotic respiratory viruses is essential to inform the development of appropriate interventions and outbreak responses. Here we target individuals with a high frequency of animal exposure in Vietnam. Three-year community-based surveillance was conducted in Vietnam during 2013-2016. We enrolled a total of 581 individuals (animal-raising farmers, slaughterers, animal-health workers, and rat traders), and utilized reverse transcription-polymerase chain reaction to detect 15 common respiratory viruses in pooled nasal-throat swabs collected at baseline or acute respiratory disease episodes. A respiratory virus was detected in 7.9% (58 of 732) of baseline samples, and 17.7% (136 of 770) of disease episode samples (P <.001), with enteroviruses (EVs), rhinoviruses and influenza A virus being the predominant viruses detected. There were temporal and spatial fluctuations in the frequencies of the detected viruses over the study period, for example, EVs and influenza A viruses were more often detected during rainy seasons. We reported the detection of common respiratory viruses in individuals with a high frequency of animal exposure in Vietnam, an emerging infectious disease hotspot. The results show the value of baseline/control sampling in delineating the causative relationships and have revealed important insights into the ecological aspects of EVs, rhinoviruses and influenza A and their contributions to the burden posed by respiratory infections in Vietnam.Peer reviewe

    Pichia pastoris versus Saccharomyces cerevisiae:a case study on the recombinant production of human granulocyte-macrophage colony-stimulating factor

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    BACKGROUND: Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) is a glycoprotein that has been approved by the FDA for the treatment of neutropenia and leukemia in combination with chemotherapies. Recombinant hGM-CSF is produced industrially using the baker's yeast, Saccharomyces cerevisiae, by large-scale fermentation. The methylotrophic yeast, Pichia pastoris, has emerged as an alternative host cell system due to its shorter and less immunogenic glycosylation pattern together with higher cell density growth and higher secreted protein yield than S. cerevisiae. In this study, we compared the pipeline from gene to recombinant protein in these two yeasts. RESULTS: Codon optimization in silico for both yeast species showed no difference in frequent codon usage. However, rhGM-CSF expressed from S. cerevisiae BY4742 showed a significant discrepancy in molecular weight from those of P. pastoris X33. Analysis showed purified rhGM-CSF species with molecular weights ranging from 30 to more than 60 kDa. Fed-batch fermentation over 72 h showed that rhGM-CSF was more highly secreted from P. pastoris than S. cerevisiae (285 and 64 mg total secreted protein/L, respectively). Ion exchange chromatography gave higher purity and recovery than hydrophobic interaction chromatography. Purified rhGM-CSF from P. pastoris was 327 times more potent than rhGM-CSF from S. cerevisiae in terms of proliferative stimulating capacity on the hGM-CSF-dependent cell line, TF-1. CONCLUSION: Our data support a view that the methylotrophic yeast P. pastoris is an effective recombinant host for heterologous rhGM-CSF production

    Evolution of average multiplicities of quark and gluon jets

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    The energy evolution of average multiplicities of quark and gluon jets is studied in perturbative QCD. Higher order (3NLO) terms in the perturbative expansion of equations for the generating functions are found. First and second derivatives of average multiplicities are calculated. The mean multiplicity of gluon jets is larger than that of quark jets and evolves more rapidly with energy. It is shown which quantities are most sensitive to higher order perturbative and nonperturbative corrections. We define the energy regions where the corrections to different quantities are important. The latest experimental data are discussed.Comment: 23 pages including 3 figures. Version 2 contains small correction to equation (41

    Correlation and high-resolution timing for Paleo-tethys Permian-Triassic boundary exposures in Vietnam and Slovenia using geochemical, geophysical and biostratigraphic data sets

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    Two Permian-Triassic boundary (PTB) successions, Lung Cam in Vietnam, and Lukač in Slovenia, have been sampled for high-resolution magnetic susceptibility, stable isotope and elemental chemistry, and biostratigraphic analyses. These successions are located on the eastern (Lung Cam section) and western margins (Lukač section) of the Paleo-Tethys Ocean during PTB time. Lung Cam, lying along the eastern margin of the Paleo-Tethys Ocean provides an excellent proxy for correlation back to the GSSP and out to other Paleo-Tethyan successions. This proxy is tested herein by correlating the Lung Cam section in Vietnam to the Lukač section in Slovenia, which was deposited along the western margin of the Paleo-Tethys Ocean during the PTB interval. It is shown herein that both the Lung Cam and Lukač sections can be correlated and exhibit similar characteristics through the PTB interval. Using time-series analysis of magnetic susceptibility data, high-resolution ages are obtained for both successions, thus allowing relative ages, relative to the PTB age at ~252 Ma, to be assigned. Evaluation of climate variability along the western and eastern margins of the Paleo-Tethys Ocean through the PTB interval, using d18O values indicates generally cooler climate in the west, below the PTB, changing to generally warmer climates above the boundary. A unique Black Carbon layer (elemental carbon present by agglutinated foraminifers in their test) below the boundary exhibits colder temperatures in the eastern and warmer temperatures in the western Paleo-Tethys Ocean.ReferencesBalsam W., Arimoto R., Ji J., Shen Z, 2007. Aeolian dust in sediment: a re-examination of methods for identification and dispersal assessed by diffuse reflectance spectrophotometry. International Journal of Environment and Health, 1, 374-402.Balsam W.L., Otto-Bliesner B.L., Deaton B.C., 1995. Modern and last glacial maximum eolian sedimentation patterns in the Atlantic Ocean interpreted from sediment iron oxide content. Paleoceanography, 10, 493-507.Berggren W.A., Kent D.V., Aubry M-P., Hardenbol J., 1995. Geochronology, Time Scales and Global Stratigraphic Correlation. SEPM Special Publication #54, Society for Sedimentary Geology, Tulsa, OK, 386p.Berger A., Loutre M.F., Laskar J., 1992. Stability of the astronomical frequencies over the Earth's history for paleoclimate studies. Science, 255, 560-566.Bloemendal J., deMenocal P., 1989. Evidence for a change in the periodicity of tropical climate cycles at 2.4 Myr from whole-core magnetic susceptibility measurements. Nature, 342, 897-900.Chen J., Shen S-j., Li X-h., Xu Y-g., Joachimski M.M., Bowring S.A., Erwin D.H., Yuan D-x., Chen B., Zhang H., Wang Y., Cao C-q, Zheng Q-f., Mu L., 2016. High-resolution SIMS oxygen isotope analysis on conodont apatite from South China and implications for the end-Permian mass extinction. Palaeogeography, Palaeoclimatology, Palaeoecology, 448, 26-38.Da Silva A-C., Boulvain F., 2002. Sedimentology, magnetic susceptibility and isotopes of a Middle Frasnian carbonate platform: Tailfer Section, Belgium. Facies, 46, 89-102.Da Silva A.-C., Boulvain F., 2005. Upper Devonian carbonate platform correlations and sea level variations recorded in magnetic susceptibility. Palaeogeography, Palaeoclimatology, Palaeoecology, 240, 373-388.Dettinger M.D., Ghil M., Strong C.M., Weibel W., Yiou P., 1995. Software expedites singular-spectrum analysis of noisy time series. EOS. Transactions of the American Geophysical Union, 76, 12-21.Dinarès-Turell J., Baceta J.I., Bernaola G., Orue-Etxebarria X., Pujalte V., 2007. Closing the Mid-Palaeocene gap: Toward a complete astronomically tuned Palaeocene Epoch and Selandian and Thanetian GSSPs at Zumaia (Basque Basin, W Pyrenees). Earth Planetary Science Letters, 262, 450-467.Ellwood B.B., García-Alcalde J.L., El Hassani A., Hladil J., Soto F.M., Truyóls-Massoni M., Weddige K., Koptikova L., 2006. Stratigraphy of the Middle Devonian Boundary: Formal Definition of the Susceptibility Magnetostratotype in Germany with comparisons to Sections in the Czech Republic, Morocco and Spain. Tectonophysics, 418, 31-49.Ellwood B.B., Wang W.-H., Tomkin J.H., Ratcliffe K.T., El Hassani A., Wright A.M., 2013. Testing high resolution magnetic susceptibility and gamma gradiation methods in the Cenomanian-Turonian (Upper Cretaceous) GSSP and near-by coeval section. Palaeogeography, Palaeoclimatology, Palaeoecology, 378, 75-90.Ellwood B.B., Wardlaw B.R., Nestell M.K., Nestell G.P., Luu Thi Phuong Lan, 2017. Identifying globally synchronous Permian-Triassic boundary levels in successions in China and Vietnam using Graphic Correlation. Palaeogeography, Palaeoclimatology, Palaeoecology, 485, 561-571.Ghil M., Allen R.M., Dettinger M.D., Ide K., Kondrashov D., Mann M.E., Robertson A., Saunders A., Tian Y., Varadi F., Yiou P., 2002. Advanced spectral methods for climatic time series. Reviews of Geophysics, 40, 3.1-3.41. http://dx.doi.org/10.1029/2000RG000092.Gradstein F.M., Ogg J.G., Smith A.G., 2004. A geologic Time Scale 2004. Cambridge University Press, England, 589p.Hartl P., Tauxe L., Herbert T., 1995. Earliest Oligocene increase in South Atlantic productivity as interpreted from “rock magnetics” at Deep Sea drilling Site 522. Paleoceanography, 10, 311-326.Imbrie J., Hays J.D., Martinson D.G., McIntyre A., Mix A.C., Morley J.J., Pisias N.G., Prell W.L., Shackleton N.J., 1984. The Orbital Theory of Pleistocene Climate: Support from a Revised Chronology of the Marine Delta 18O Record. In Berger A.L., Imbrie J., Hays J., Kukla G., Saltzman B. (Eds.), Milankovitch and Climate, Part I, Kluwer Academic Publishers, 269-305.Mead G.A., Yauxe L., LaBrecque J.L., 1986. Oligocene paleoceanography of the South Atlantic: paleoclimate implications of sediment accumulation rates and magnetic susceptibility. Paleoceanography, 1, 273-284.Salvador A., (Ed.), 1994. International Stratigraphic Guide: The International Union of Geological Sciences and The Geological Society of America, Inc., 2nd Edition, 214p.Scotese C.R., 2001. Atlas of Earth History, Volume 1, Paleogeography, PALEOMAP Project, Arlington, Texas, 52p.Scotese C.R., 2013. Map Folio 49, Permo-Triassic Boundary (251 Ma), PALEOMAP PaleoAtlas for ArcGIS, Triassic and Jurassic Paleogeographic, Paleoclimatic and Plate Tectonic Reconstructions, PALEOMAP Project, Evanston, IL, 3.Shackleton N.J., Crowhurst S.J., Weedon G.P., Laskar J., 1999. Astronomical calibration of Oligocene-Miocene time. Philosophical Transactions of the Royal Society London, A357, 1907-1929.Shaw A.B., 1964. Time in Stratigraphy. New York, Mc Graw Hill, 365p.Shen S.-Z., Crowley J.L., Wang Y., Bowring S.A., Erwin D.H., Henderson C.M., Ramezani J., Zhang H., Shen Y.,Wang X.-D., Wang W., Mu L., Li W.-Z., Tang Y.-G., Liu X.-L., Liu X.-L., Zeng Y., Jiang Y.-F., Jin Y.-G., 2011a. High-precision geochronologic dating constrains probable causes of Earth’s largest mass extinction. Science, 334, 1367-1372. Doi:10.1126/science.1213454.Swartzendruber L.J., 1992. Properties, units and constants in magnetism. Journal of Magnetic Materials, 100, 573-575.Weedon G.P., Jenkyns H.C., Coe A.L., Hesselbo S.P., 1999. Astronomical calibration of the Jurassic time-scale from cyclostratigraphy in British mudrock formations. Philosophical Transactions of the Royal Society London, A357, 1787-1813.Weedon G.P., Shackleton N.J., Pearson P.N., 1997. The Oligocne time scale and cyclostratigraphy on the Ceara Rise, western equatorial Atlantic. In: Schackleton N.J., Curry W.B., Richter C., and Bralower T.J. (Eds.). Proceedings of the Ocean Drilling Program, Scientific Results, 154, 101-114.Whalen M.T., Day J.E., 2008. Magnetic Susceptibility, Biostratigraphy, and Sequence Stratigraphy: Insights into Devonian Carbonate Platform Development and Basin Infilling, Western Alberta. Papers on Phanerozoic Reef Carbonates in Honor of Wolfgang Schlager. SEPM (Society for Sedimentary Geology) Special Publication, 89, 291-314

    Redondoviridae: High Prevalence and Possibly Chronic Shedding in Human Respiratory Tract, But No Zoonotic Transmission

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    Redondoviridae is a recently discovered DNA virus family consisting of two species, vientovirus and brisavirus. Here we used PCR amplification and sequencing to characterize redondoviruses in nasal/throat swabs collected longitudinally from a cohort of 58 individuals working with animals in Vietnam. We additionally analyzed samples from animals to which redondovirus DNA-positive participants were exposed. Redondoviruses were detected in approximately 60% of study participants, including 33% (30/91) of samples collected during episodes of acute respiratory disease and in 50% (29/58) of baseline samples (with no respiratory symptoms). Vientovirus (73%; 24/33) was detected more frequently in samples than brisaviruses (27%; 9/33). In the 23 participants with at least 2 redondovirus-positive samples among their longitudinal samples, 10 (43.5%) had identical redondovirus replication-gene sequences detected (sampling duration: 35–132 days). We found no identical redondovirus replication genes in samples from different participants, and no redondoviruses were detected in 53 pooled nasal/throat swabs collected from domestic animals. Phylogenetic analysis described no large-scale geographical clustering between viruses from Vietnam, the US, Spain, and China, indicating that redondoviruses are highly genetically diverse and have a wide geographical distribution. Collectively, our study provides novel insights into the Redondoviridae family in humans, describing a high prevalence, potentially associated with chronic shedding in the respiratory tract with lack of evidence of zoonotic transmission from close animal contacts. The tropism and potential pathogenicity of this viral family remain to be determined
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