Hammersley, L. C.
2016-12-01
The National Science Foundation's Louis Stokes Alliances for Minority Participation (LSAMP) program supports alliances of institutions in their efforts to broaden participation in STEM and diversify the STEM workforce. There are currently 42 LSAMP alliances across the nation. Formed in 1993, the California State University LSAMP program (CSU-LSAMP) is an alliance of all 23 campuses of the CSU system and serves over 3,000 students per year. The primary goals of CSU-LSAMP are to increase persistence and graduation rates for URM participants, increase the number of STEM degrees awarded by the CSU to URM students, and increase the number of CSU-LSAMP students who advance to STEM graduate study. CSU-LSAMP activities are focused on four objectives - academic support (e.g. supplemental instruction & peer mentoring), support at transition points (e.g. first time freshmen & transfer students), research experiences (including international research experiences), and professional development (e.g. conference presentations & graduate school preparation activities). Financial support is offered in the form of textbook assistance, research stipends, and travel awards. We maintain a structure that allows campuses to tailor their programs to meet the needs of their own student populations but that also ties the Alliance together with a set of common activities, goals and policies. External evaluation of the program shows that our approach has been highly successful and can provide useful lessons for other programs focused on broadening participation. Since 1994, the number of URM students enrolled in STEM disciplines at CSU campuses has more than doubled and the number of STEM degrees to URM students has almost tripled. Persistence and graduation rates for URM students who participate in CSU-LSAMP are almost twice those of URM non-participants and equal to those of non-URM students. Of the students who participated in the past 15 years, 42 percent either earned a post
Institute of Scientific and Technical Information of China (English)
张顺伍
2001-01-01
One day Louis was in arestaurantfriend read 1 ofwith a friend. The an article about awriting that could beused in the 2 . It was called“ight writing” . Louis was ex-cited. He went to the 3 ofthe system and asked manyquestion.
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
On general design, fabrics and styles my heart belongs to the reminiscent 40's of Louis Vuitton. with their classic chequered patterns, V collars over 3 buttons, is an acclamation of the traditional Oxford college culture.
Jaime Wisniak
2015-01-01
Louis Mialhe (1807-1886) fue un médico y farmacéutico francés que estudió las transformaciones químicas de los cloruros de mercurio, la fabricación del éter etílico, etc., y numerosos fenómenos fisiológicos en seres humanos, entre ellos, la diabetes, los mecanismos de la asimilación de carbohidratos, grasas, y albuminoides, la acción de la saliva, pepsina, y el jugo gástrico sobre los alimentos, la acción de diversos purgantes de acuerdo con su naturaleza, etc. Sus trabajos sobre fisiología h...
Directory of Open Access Journals (Sweden)
Jaime Wisniak
2015-01-01
Full Text Available Louis Mialhe (1807-1886 fue un médico y farmacéutico francés que estudió las transformaciones químicas de los cloruros de mercurio, la fabricación del éter etílico, etc., y numerosos fenómenos fisiológicos en seres humanos, entre ellos, la diabetes, los mecanismos de la asimilación de carbohidratos, grasas, y albuminoides, la acción de la saliva, pepsina, y el jugo gástrico sobre los alimentos, la acción de diversos purgantes de acuerdo con su naturaleza, etc. Sus trabajos sobre fisiología humana lo llevaron a descubrir la presencia de una diastasa en la saliva y a sugerir una teoría sobre el origen de la diabetes.
SUNY Youth Internship Program: A Summary Review.
Winter, Gene M.; Fadale, LaVerna M.
A Youth Internship Program (YIP) has been developed at seven community colleges of the State University of New York (SUNY) to improve the employability potential of unemployed, out-of-school, economically disadvantaged youth between 16 and 21 years of age. Components of the seven programs examined differ, but all address six main activities:…
The SUNY Oneonta Second Life Music Project
Greenberg, James; Nepkie, Janet; Pence, Harry E.
2009-01-01
Do online virtual worlds represent a viable learning environment for higher education? Many Second Life classes resemble their real life equivalents, but some faculty are exploring the potential of virtual worlds for less-traditional teaching. This article describes one such effort, the SUNY Oneonta Music Project, in which faculty and students…
Waste to Energy at SUNY Cobleskill
2011-05-10
GASIFICATION Ash ENERGYWaste T ~ 800oC Partial Combustion O/C ~1/3 • Energy Production • Reduced Fuel Usage for transportation • Increased Energy...Environmental Science and Technology at SUNY Cobleskill. CEST MISSION • Reduce society’s dependency on fossil fuels. • Research conversion of biomass ...on chamber temperature) • Syngas • Char • Steam • Syngas clean up outputs • Hydrogen • Carbon Monoxide • Ash Nitrogen Sulfate Precipitates 22
2014-01-01
Louis Dick, a CERN experimental physicist of international renown, passed away on 14 July. Louis in his office, a veritable archaeological wonder with strata of documents corresponding to various eras of physics. Born in Geneva on 27 April 1921, Louis obtained a physics degree at ETH-Zurich in 1946 before moving to the Institut du Radium in Paris, where he joined the group led by Frédéric and Irène Joliot-Curie. He took a leave of absence in 1957 to go to CERN, where he remained until well beyond his retirement in 1986. In the late 1950s and early 1960s, Louis worked at CERN’s Synchrocyclotron (SC) and later on studies at the Proton Synchrotron (PS). When the first polarised proton target arrived at CERN from Saclay in 1963, Louis proposed using it for studies of spin effects in pion-proton elastic scattering at the PS, and between 1964 and 1966 sizeable spin effects were found. Louis and his collaborators then continued these studies wi...
Stokes examines NASA program management
Leath, Audrey T.
As NASA gears up for another attempt at redesigning Space Station Freedom, some in Congress are wondering whether the space agency has learned any lessons from a number of costly past mistakes. Louis Stokes (D-Ohio), the new chairman of the House Appropriations Veterans Affairs, Housing and Urban Development, and Independent Agencies Subcommittee, held a hearing on March 17 to examine unanticipated cost growth in a variety of projects, including the space toilet, the advanced turbo pump for the shuttle, and the Mars Observer, as well as the space station. Stokes seemed well-suited to this oversight role, asking well-informed and probing questions rather than accusatory ones. The witnesses, NASA head Daniel Goldin and many of his top managers (most of whom were not in their present positions when the projects were initiated), analyzed past errors and offered useful measures for avoiding similar problems in the future.
Kivland, Sharon
2013-01-01
A small catalogue of Louis XVI furniture, which makes a rapport between style and revolution, furniture and its naming, femininity and the neo-classical. The ambience is welcoming, despite its sobriety and a whiff of the Terror. The book contains six duo-tone photographic plates, tipped-in by hand. The book is published in a edition of 50 copies at the kind invitation of AM Bruno on the occasion of the 16th International Contemporary Artists' Book Fair, Leeds.
Greenslade, Thomas B.
2011-10-01
The St. Louis Motor, invented in 1909, is unique among physics apparatus for being named for a geographical place rather than a physicist. The sturdy little device (Fig. 1) has never been out of production. Any older school or physics department that has not done a catastrophic housecleaning in the last 20 years will certainly have a small flock of them in the back room.
Louis Pasteur surgical revolution.
Toledo-Pereyra, Luis H
2009-01-01
Louis Pasteur (1822-1895) is considered the most notable medical scientist of his time and perhaps one of the most distinguished of all times in the history of medicine. From Dole in France to Paris, from a student of crystals to "living ferments," and from chemistry to biology and medicine, Pasteur changed the world for the benefit of humanity. The genius of Pasteur dealt with the most pressing issues of his time, basing the germ theory on the effects that microorganisms had on fermentation and putrefaction of organic matter, which gave birth to the science of bacteriology. Many other difficult problems in medicine and biology were tackled by Pasteur, culminating in the spectacular results seen with the treatment of rabies. Surgery was no exception to the scientific conquests of Pasteur. The transformation of the surgical world arose from the antiseptic concepts of Lister that were based on the germ theory of the disease, which had been derived from the germ theory of fermentation and putrefaction discovered by Pasteur. The acceptance of these principles represented the surgical revolution brought on by the science of Pasteur, a revolution that is now accepted in our daily care of surgical patients.
Directory of Open Access Journals (Sweden)
José Ángel García-Rodríguez
2008-10-01
Full Text Available The Story of Louis Pasteur is considered one of the first biopics – term that comes from the association of “biography” and “picture” – in the history of cinema. Directed by William Dieterle in 1936, it was distributed in Spain under the curious name of “La tragedia de Louis Pasteur” (The tragedy of Louis Pasteur. This tragedy is a consequence of the lack of understanding and culture, of the unfairness and ingratitude, which were all magnified in the figure of a man whose banner was the science and, according to him, the well-being of mankind depended on its application. The film is structured into three parts connected to events related to Pasteur´s studies in the field of Microbiology and infectious diseases: Microbial theory about the disease which was present all through the film and the main axe of the plot; studies in anthrax and research into rabies.
St. Louis FUSRAP Lessons Learned
Energy Technology Data Exchange (ETDEWEB)
Eberlin, J.; Williams, D.; Mueller, D.
2003-02-26
The purpose of this paper is to present lessons learned from fours years' experience conducting Remedial Investigation and Remedial Action activities at the St. Louis Downtown Site (SLDS) under the Formerly Utilized Sites Remedial Action Program (FUSRAP). Many FUSRAP sites are experiencing challenges conducting Remedial Actions within forecasted volume and budget estimates. The St. Louis FUSRAP lessons learned provide insight to options for cost effective remediation at FUSRAP sites. The lessons learned are focused on project planning (budget and schedule), investigation, design, and construction.
Louis Pasteur's beer of revenge.
Baxter, A G
2001-12-01
Although by the mid-nineteenth century evidence existed for an association between micoorganisms and disease, it was the combined efforts of Louis Pasteur and Robert Koch that created the germ theory of disease--the theory that specific microbes cause specific diseases. Surprisingly, the relationship between the two founders of microbiology and immunology was far from friendly.
Validation of the NSRDB-SUNY global horizontal irradiance in California
Energy Technology Data Exchange (ETDEWEB)
Nottrott, Anders; Kleissl, Jan [Mechanical and Aerospace Engineering, University of California, San Diego (United States)
2010-10-15
Satellite derived global horizontal solar irradiance (GHI) from the SUNY modeled dataset in the National Solar Radiation Database (NSRDB) was compared to measurements from 27 weather stations in California during the years 1998-2005. The statistics of spatial and temporal differences between the two datasets were analyzed and related to meteorological phenomena. Overall mean bias errors (MBE) of the NSRDB-SUNY indicated a GHI overprediction of 5%, which is smaller than the sensor accuracy of ground stations. However, at coastal sites, year-round systematic positive MBEs in the NSRDB-SUNY data up to 18% were observed and monthly MBEs increased up to 54% in the summer months during the morning. These differences were explained by a tendency for the NSRDB-SUNY model to overestimate GHI under cloudy conditions at the coast during summer mornings. A persistent positive evening MBE which was independent of site location and cloudiness occurred at all stations and was explained by an error in the time-shifting method applied in the NSRDB-SUNY. A correction method was derived for these two errors to improve the accuracy of the NSRDB-SUNY data in California. (author)
[Saint Louis encephalitis: case report].
Carballo, Carolina; Cabana, Magdalena; Ledezma, Francisca; Pascual, Carolina; Cazes, Claudia; Mistchenko, Alicia; López, Eduardo
2016-08-01
Saint Louis encephalitis is transmitted by Culex mosquitoes. In Argentina sporadic cases are registered. Symptomatic illness is unusual in children. We present a case of meningoencephalitis caused by an uncommon viral infection. The clinical signs and symptoms are unusual for pediatric patients and the bilateral thalamic compromise showed on magnetic resonance has not been described previously. An 8-year-old girl consulted due to fever, behavior disorders and ataxia. Clonus and neck stiffness were detected at physical exam. Cerebrospinal fluid revealed mononuclear leukocytosis; bilateral ischemic compromise was observed in thalamus by magnetic resonance. Saint Louis virus was confirmed by serology: serum and cerebrospinal fluid IgM were positive during the acute phase of the disease and serum IgG was positive four weeks later. Most of the signs and symptoms of the disease were resolved, however mild behavior disorders were observed as acute sequelae up to 45 days after hospital discharge.
SUNY beamline facilities at the National Synchrotron Light Source (Final Report)
Energy Technology Data Exchange (ETDEWEB)
Coppens, Philip
2003-06-22
The DOE sponsored SUNY synchrotron project has involved close cooperation among faculty at several SUNY campuses. A large number of students and postdoctoral associates have participated in its operation which was centered at the X3 beamline of the National Synchrotron Light Source at Brookhaven National Laboratory. Four stations with capabilities for Small Angle Scattering, Single Crystal and Powder and Surface diffraction and EXAFS were designed and operated with capability to perform experiments at very low as well as elevated temperatures and under high vacuum. A large amount of cutting-edge science was performed at the facility, which in addition provided excellent training for students and postdoctoral scientists in the field.
Nonlinear Stokes Mueller Polarimetry
Samim, Masood; Barzda, Virginijus
2015-01-01
The Stokes Mueller polarimetry is generalized to include nonlinear optical processes such as second- and third-harmonic generation, sum- and difference-frequency generations. The overall algebraic form of the polarimetry is preserved, where the incoming and outgoing radiations are represented by column vectors and the intervening medium is represented by a matrix. Expressions for the generalized nonlinear Stokes vector and the Mueller matrix are provided in terms of coherency and correlation matrices, expanded by higher-dimensional analogues of Pauli matrices. In all cases, the outgoing radiation is represented by the conventional $4\\times 1$ Stokes vector, while dimensions of the incoming radiation Stokes vector and Mueller matrix depend on the order of the process being examined. In addition, relation between nonlinear susceptibilities and the measured Mueller matrices are explicitly provided. Finally, the approach of combining linear and nonlinear optical elements is discussed within the context of polarim...
Toward A Competency-Based Teacher Education Program in Foreign Languages at SUNY/Buffalo.
Papalia, Anthony
SUNY/Buffalo's competency-based teacher education program in foreign languages emphasizes: (1) a field-centered program, (2) a multi-institutional pattern of organizations, (3) feedback to students regarding their progress, (4) preservice/inservice continuum. The competencies required of foreign language teachers include: a practical command of…
DOE Closeout Report from SUNY Albany High Energy Physics to Department of Energy Office of Science.
Energy Technology Data Exchange (ETDEWEB)
Ernst, Jesse [SUNY Albany; Jain, Vivek
2014-08-15
A report from the SUNY Albany Particle Physics Group summarizing our activities on the ATLAS experiment at the Large Hadron Collider. We summarize our work: on data analysis projects, on efforts to improve detector performance, and on service work to the experiment.
The new borders of Saint Louis
Directory of Open Access Journals (Sweden)
Fabrice Delsahut
2012-09-01
Full Text Available In 1904 the Olympic and Anthropologic Games in Saint Louis, Missouri, were lost in the chaos of the Louisiana Purchase (Universal Exposition. Although the expected universal spirit, for a long time Saint Louis expressed racial prejudices of its personal. This paper shows up how Sport Sciences and growing up Anthropology acted together in sense of serving questioned causes like racial ranking and colonization right. They were important in improving a feeling of nation in North American that took in grant sport as part of its constitution. The Universal Exposition and Market of Saint Louis offered new possibilities in definition of technological, racial, geographic and corporal borders.
Louis Kahn. Ajaloost ajatust otsides / Karin Paulus
Paulus, Karin, 1975-
2006-01-01
6.-7. okt. 2006. a. toimuvad Kuressaares esimesed Kahni päevad. Eestist pärit ameerika arhitekti Louis Isadore Kahni (1901-1974) eluloolisi andmeid ja loomingust. Kommenteerivad Mart Kalm, Raine Karp, Veljo Kaasik, Toivo Tammik
Louis Kahn. Ajaloost ajatust otsides / Karin Paulus
Paulus, Karin, 1975-
2006-01-01
6.-7. okt. 2006. a. toimuvad Kuressaares esimesed Kahni päevad. Eestist pärit ameerika arhitekti Louis Isadore Kahni (1901-1974) eluloolisi andmeid ja loomingust. Kommenteerivad Mart Kalm, Raine Karp, Veljo Kaasik, Toivo Tammik
Obituary: John Louis Perdrix (1926-2005)
Orchiston, W.
2005-12-01
On 27 June 2005 the Journal of Astronomical History and Heritage lost its founder and Australia lost one of its leading historians of astronomy when John Louis Perdrix died in Dubai after a brief battle with cancer.
Directory of Open Access Journals (Sweden)
Hannelore Breckner
2000-01-01
Full Text Available We consider a stochastic equation of Navier-Stokes type containing a noise part given by a stochastic integral with respect to a Wiener process. The purpose of this paper is to approximate the solution of this nonlinear equation by the Galerkin method. We prove the convergence in mean square.
Eesti mees - arhitekt Louis Kahn / Toivo Tammik
Tammik, Toivo
2006-01-01
1901. aastal Saaremaal sündinud mehest, kelle elutee viis USA-sse ja koostöös eestlase August Komendantiga valmisid suurepärased projektid. Eestis, Saaremaal, valmistutakse Louis Kahni päevadeks 2006. aasta oktoobris
Eesti mees - arhitekt Louis Kahn / Toivo Tammik
Tammik, Toivo
2006-01-01
1901. aastal Saaremaal sündinud mehest, kelle elutee viis USA-sse ja koostöös eestlase August Komendantiga valmisid suurepärased projektid. Eestis, Saaremaal, valmistutakse Louis Kahni päevadeks 2006. aasta oktoobris
St. Louis Educational Museum: A Centennial Commemoration
Allen, James A.
2005-01-01
The St. Louis, Missouri Educational Museum has its roots in the 1904 Centennial Exposition, held at Forest Park on the edge of the city. The theme of the exposition was education and technology. Seventy thousand local school children visited the exposition, and at its conclusion an initiative was launched to purchase some of the exhibitions as…
Inventory of Endangered Plants, Saint Louis District,
1977-01-01
MISSOURIRVR lIIN .. .Jee . j ..- .. ,,,....VER ,RONDAL t7S - .I" D1ŕC / LITLE OCKDISTRICT \\/ SA T "PTRK DIVISIONEI O PER .......... tKENTUAKY tQ*StJ tim ...on September 10, 1937, by B. C. Tharp , that may prove to be this species. The Cass County station is within the boundaries of the St. Louis District
Baseline risk assessment for exposure to contaminants at the St. Louis Site, St. Louis, Missouri
Energy Technology Data Exchange (ETDEWEB)
1993-11-01
The St. Louis Site comprises three noncontiguous areas in and near St. Louis, Missouri: the St. Louis Downtown Site (SLDS), the St. Louis Airport Storage Site (SLAPS), and the Latty Avenue Properties. The main site of the Latty Avenue Properties includes the Hazelwood Interim Storage Site (HISS) and the Futura Coatings property, which are located at 9200 Latty Avenue. Contamination at the St. Louis Site is the result of uranium processing and disposal activities that took place from the 1940s through the 1970s. Uranium processing took place at the SLDS from 1942 through 1957. From the 1940s through the 1960s, SLAPS was used as a storage area for residues from the manufacturing operations at SLDS. The materials stored at SLAPS were bought by Continental Mining and Milling Company of Chicago, Illinois, in 1966, and moved to the HISS/Futura Coatings property at 9200 Latty Avenue. Vicinity properties became contaminated as a result of transport and movement of the contaminated material among SLDS, SLAPS, and the 9200 Latty Avenue property. This contamination led to the SLAPS, HISS, and Futura Coatings properties being placed on the National Priorities List (NPL) of the US Environmental Protection Agency (EPA). The US Department of Energy (DOE) is responsible for cleanup activities at the St. Louis Site under its Formerly Utilized Sites Remedial Action Program (FUSRAP). The primary goal of FUSRAP is the elimination of potential hazards to human health and the environment at former Manhattan Engineer District/Atomic Energy Commission (MED/AEC) sites so that, to the extent possible, these properties can be released for use without restrictions. To determine and establish cleanup goals for the St. Louis Site, DOE is currently preparing a remedial investigation/feasibility study-environmental impact statement (RI/FS-EIS). This baseline risk assessment (BRA) is a component of the process; it addresses potential risk to human health and the environment associated wi
Energy Technology Data Exchange (ETDEWEB)
Geiger, David K [State Univ. of New York (SUNY), Geneseo, NY (United States)
2015-12-31
An Agilent 400-MR nuclear magnetic resonance (NMR) spectrometer and ancillary equipment were purchased, which are being used for molecular structure elucidation. The instrumentation is housed in a pre-existing facility designed specifically for its use. This instrument package is being used to expand the research and educational efforts of the faculty and students at SUNY-Geneseo and is made available to neighboring educational institutions and business concerns. Funds were also used for training of College personnel, maintenance of the instrumentation, and installation of the equipment.
Louis Pasteur, the Father of Immunology?
Kendall A Smith
2012-01-01
Louis Pasteur is traditionally considered as the progenitor of modern immunology because of his studies in the late nineteenth century that popularized the germ theory of disease, and that introduced the hope that all infectious diseases could be prevented by prophylactic vaccination, as well as also treated by therapeutic vaccination, if applied soon enough after infection. However, Pasteur was working at the dawn of the appreciation of the microbial world, at a time when the notion of such ...
Ameerikast Kuressaare lossi Louis Kahni hingust otsima / Sirli Tooming
Tooming, Sirli
2016-01-01
Suvel viibisid Kuressaares kaks härrasmeest Ameerikast, arhitekt Louis Kahni projekti järgi valminud eramu omanikud, kelle eesmärk oli külastada Kuressaare lossi kui Louis Kahni inspiratsiooniallikat. Neid saatis Kuressaares Louis Kahni näituse "Kahn. Saarlane" üks initsiaatoritest Heie Treier. Vestlusest ka Heie Treieriga näitusest ja ameerika külaliste arhitektuurihuvist
Chicago-St. Louis high speed rail plan
Energy Technology Data Exchange (ETDEWEB)
Stead, M.E.
1994-12-31
The Illinois Department of Transportation (IDOT), in cooperation with Amtrak, undertook the Chicago-St. Louis High Speed Rail Financial and Implementation Plan study in order to develop a realistic and achievable blueprint for implementation of high speed rail in the Chicago-St. Louis corridor. This report presents a summary of the Price Waterhouse Project Team`s analysis and the Financial and Implementation Plan for implementing high speed rail service in the Chicago-St. Louis corridor.
Ameerikast Kuressaare lossi Louis Kahni hingust otsima / Sirli Tooming
Tooming, Sirli
2016-01-01
Suvel viibisid Kuressaares kaks härrasmeest Ameerikast, arhitekt Louis Kahni projekti järgi valminud eramu omanikud, kelle eesmärk oli külastada Kuressaare lossi kui Louis Kahni inspiratsiooniallikat. Neid saatis Kuressaares Louis Kahni näituse "Kahn. Saarlane" üks initsiaatoritest Heie Treier. Vestlusest ka Heie Treieriga näitusest ja ameerika külaliste arhitektuurihuvist
Papalia, Anthony; And Others
A series of discussions among members of the language departments at SUNY/Buffalo was held to examine ways of improving language teaching methodology in the college, particularly at the second-year level. The suggestions resulting from these meetings are offered as a practical response to the decreased enrollment in language courses. The…
The Saint Louis River Idea-Slam crowd sourcing good ideas for the Saint Louis River
As part of the 2017 Saint Louis River Summit, we propose hosting an “Idea-Slam” using software originally developed by the U.S. Consumer Financial Protection Bureau. Idea-box is an open source online app/website used to collect and surface ideas from members of an or...
Pulliam, Tom; Kwak, Dochan (Technical Monitor)
1997-01-01
Implicit methods have been the workhorse for the Euler and Navier-Stokes equations for the last 25 years. The ground breaking work of Dr. Joe Steger in implementing such techniques in practical Euler and Navier-Stokes codes provided the basis for all the success in this area. This presentation will highlight his contribution and technical excellence in the area of implicit methods for CFD.
Tribute to Louis Leprince-Ringuet
2001-01-01
Louis Leprince-Ringuet, a great figure of French science, promoter of scientific cooperation in Europe and ardent supporter of CERN, passed away on 23 December 2000 at the age of 99. This multi-facetted scholar was at the same time a director of major laboratories, a renowned scientist, an outstanding teacher, instilling a passion for physics in all his pupils, a promoter of European construction, a populariser of science, a brilliant satirist, a painter and an accomplished sportsman. As a scientist, he pioneered the study of cosmic rays, establishing himself as a world authority in the field. His memory will be honoured at CERN on 3 May. After a tribute to his life by Maurice Jacob, Professor Livio Scarsi will give a lecture on the Extreme Universe Space Observatory (EUSO) programme, one of the most ambitious projects in the field of cosmic ray physics. Louis Leprince-Ringuet (right) with John B. Adams in 1961. Thursday 3 May Main Auditorium, bldg. 500 3.30 p.m Coffee 4.00 p.m. Welcome by CERN's Direc...
Louis de Broglie und die Quantenmechanik
Sievers, H
1998-01-01
In 1923 Louis de Broglie (1892-1987) discovered the material waves and six years later received the Nobel price for this discovery. Apart these well known facts this French physicist nevertheless seems to be forgotten. Details of his life are as unknown as his efforts to describe quantum mechanics in a deterministic and objective way. Especially the actual discussion concerning the interpretation of quantum mechanics seems to justify a deeper occupation with the scientific work of Louis de Broglie. In this context the important influence of Albert Einstein is of special interest; for his photons announce the existence of material waves and it may surprise that Einstein himself did not postulate them. The basis of this short scientific biography are the publications of de Broglie (a complete bibliography is given at the end), some more or less short memories of his students and some unpublished documents found in the "Archives de l'Academie des Sciences" at Paris. The original text of the correspondence betwee...
Raper, J E
1977-04-01
Since February 1976, The Medical Library Center of New York, with the assistance of the SUNY/OCLC Network, has offered, on a subscription basis, a centralized automated cataloging service to health science libraries in the greater metropolitan New York area. By using workforms and prints of OCLC record (amended by the subscribing participants), technical services personnel at the center have fed cataloging data, via a CRT terminal, into the OCLC system, which provides (1) catalog cards, received in computer filing order; (2) book card, spine, and pocket labels; (3) accessions lists; and (4) data for eventual production of book catalogs and union catalogs. The experience of the center in the development, implementation, operation, and budgeting of its shared cataloging service is discussed.
Integrated problem-based learning in the neuroscience curriculum – the SUNY Downstate experience
Directory of Open Access Journals (Sweden)
Trappler Brian
2006-09-01
Full Text Available Abstract Background This paper reports the author's initial experience as Block Director in converting a Conventional Curriculum into a problem-based learning model (PBL for teaching Psychopathology. As part of a wide initiative in curriculum reform, Psychopathology, which was a six-week course in the second-year medical school curriculum, became integrated into a combined Neuroscience block. The study compares curriculum conversion at State University of New York (SUNY, Downstate, with the experiences at other medical centres that have instituted similar curricula reform. Methods Student satisfaction with the Conventional and PBL components of the Neuroscience curriculum was compared using questionnaires and formal discussions between faculty and a body of elected students. The PBL experience in Psychopathology was also compared with that of the rest of the Neuroscience Block, which used large student groups and expert facilitators, while the Psychopathology track was limited to small groups using mentors differing widely in levels of expertise. Results Students appeared to indicate a preference toward conventional lectures and large PBL groups using expert facilitators in contrast to small group mentors who were not experts. Small PBL groups with expert mentors in the Psychopathology track were also rated favorably. Conclusion The study reviews the advantages and pitfalls of the PBL system when applied to a Neuroscience curriculum on early career development. At SUNY, conversion from a Conventional model to a PBL model diverged from that proposed by Howard S. Barrows where student groups define the learning objectives and problem-solving strategies. In our model, the learning objectives were faculty-driven. The critical issue for the students appeared to be the level of faculty expertise rather than group size. Expert mentors were rated more favorably by students in fulfilling the philosophical objectives of PBL. The author, by citing the
Jehaes, E; Pfeiffer, H; Toprak, K; Decorte, R; Brinkmann, B; Cassiman, J J
2001-03-01
According to official historiography, the 10-year-old Louis XVII died in the Temple of Paris on June 8, 1795. However, public rumour spread the theory that Louis XVII escaped and that his descendants would be alive today. One such putative 'Louis XVII' was Carl Wilhelm Naundorff, who died in 1845 in Delft (the Netherlands). Comparative mitochondrial DNA (mtDNA) analysis gave evidence that his remains could not be identified as those of Louis XVII. In the present study, mtDNA analysis was performed on the heart of the young boy who died in the prison of Paris in 1795. In order to obtain the strongest evidence possible, two laboratories independently analysed the heart. The results showed that the consensus mtDNA sequence of the heart was identical to that of the maternal relatives of Louis XVII.
St. Louis Airport site environmental report for calendar year 1989, St. Louis, Missouri
Energy Technology Data Exchange (ETDEWEB)
none,
1990-05-01
The environmental monitoring program, which began in 1984, continued during 1989 at the St. Louis Airport Site (SLAPS) in St. Louis County, Missouri. SLAPS and its vicinity properties, including ditches north and south of the site, were designated for cleanup as part of the Formerly Utilized Sites Remedial Action Program (FUSRAP), a United States Department of Energy (DOE) program to identify and decontaminate or otherwise control sites where residual radioactive material remains from the early years of the nation's atomic energy program. The monitoring program at SLAPS measures radon concentrations in air; external gamma dose rates; and uranium, thorium, and radium concentrations in surface water, groundwater, and sediment. Additionally, several nonradiological parameters are measured in groundwater. To assess the potential effect of SLAPS on public health, the potential radiation dose was estimated for a hypothetical maximally exposed individual. This report presents the findings of the environmental monitoring program conducted at the St. Louis Airport Site (SLAPS) during calendar year 1989. 19 refs., 13 figs., 14 tabs.
Louis Boutet de Monvel, selected works
Sjöstrand, Johannes
2017-01-01
This book features a selection of articles by Louis Boutet de Monvel and presents his contributions to the theory of partial differential equations and analysis. The works selected here reveal his central role in the development of his field, including three cornerstones: firstly, analytic pseudodifferential operators, which have become a fundamental aspect of analytic microlocal analysis, and secondly the Boutet de Monvel calculus for boundary problems for elliptic partial differential operators, which is still an important tool also in index theory. Thirdly, Boutet de Monvel was one of the first people to recognize the importance of the existence of generalized functions, whose singularities are concentrated on a single ray in phase space, which led him to make essential contributions to hypoelliptic operators and to a very successful and influential calculus of Toeplitz operators with applications to spectral and index theory. Other topics treated here include microlocal analysis, star products and deforma...
Stokes Soliton in Optical Microcavities
Yang, Qi-Fan; Yang, Ki Youl; Vahala, Kerry
2016-01-01
Solitons are wavepackets that resist dispersion through a self-induced potential well. They are studied in many fields, but are especially well known in optics on account of the relative ease of their formation and control in optical fiber waveguides. Besides their many interesting properties, solitons are important to optical continuum generation, in mode-locked lasers and have been considered as a natural way to convey data over great distances. Recently, solitons have been realized in microcavities thereby bringing the power of microfabrication methods to future applications. This work reports a soliton not previously observed in optical systems, the Stokes soliton. The Stokes soliton forms and regenerates by optimizing its Raman interaction in space and time within an optical-potential well shared with another soliton. The Stokes and the initial soliton belong to distinct transverse mode families and benefit from a form of soliton trapping that is new to microcavities and soliton lasers in general. The di...
AGN polarization modeling with STOKES
Goosmann, R W; Shoji, M; Goosmann, Rene W.
2007-01-01
We introduce a new, publicly available Monte Carlo radiative transfer code, STOKES, which has been developed to model polarization induced by scattering off free electrons and dust grains. It can be used in a wide range of astrophysical applications. Here, we apply it to model the polarization produced by the equatorial obscuring and scattering tori assumed to exist in active galactic nuclei (AGNs). We present optical/UV modeling of dusty tori with a curved inner shape and for two different dust types: one composition reproduces extinction properties of our Galaxy, and the other is derived from composite quasar spectra. The polarization spectra enable us to clearly distinguish between the two dust compositions. The STOKES code and its documentation can be freely downloaded from http://www.stokes-program.info/.
The Chinese Program at St. Louis University High School
Wang, August
1977-01-01
Chinese courses at the St. Louis University High School teach language, culture and calligraphy. Daily classes feature language labs, slides, filmstrips and movies. Statements from students testify that the language is useful and not difficult to learn. (CHK)
76 FR 56492 - Environmental Impact Statement: St. Louis County, Missouri
2011-09-13
... Charbonier Road between Earth City Expressway and Howdershell/Shackelford Road in northwestern St. Louis.../Shackelford Road on the east. Alternatives under consideration include (1) taking no action; (2...
St. Louis River water quality assessment 2012, 2013
U.S. Environmental Protection Agency — St. Louis River Area of Concern surface water nutrient (TP, TN, NOx-N, NH4-N), dissolved oxygen, and particulate (TSS, chlorophyll a) concentration data from 2012...
76 FR 49526 - Environmental Impact Statement; Saint Louis County, MN
2011-08-10
... Federal Highway Administration Environmental Impact Statement; Saint Louis County, MN AGENCY: Federal... advise the public that an Environmental Impact Statement (EIS) will be prepared to respond to the terms... INFORMATION CONTACT: Philip Forst, Environmental Specialist, Federal Highway Administration, 380 Jackson...
St. Louis River Estuary 2011 - 2013 Faucet snail location data
U.S. Environmental Protection Agency — The dataset consists of GPS coordinates for benthic invertebrate collections made in the St. Louis River Estuary in 2011 through 2013, and information on whether and...
Los juegos antropologicos de Saint-Louis
Directory of Open Access Journals (Sweden)
Fabrice Delsahut
2011-12-01
Full Text Available En 1904, en medio de la feria de la exposición universal de Saint-Louis, los Juegos olimpicos no pudieron escapar a la ascención de ideologías racistas del principios del siglo XX y contibuyeron a la discusión del mérito atlético de diferentes razas. Los organisadores prepararon competiciones especiales que llamaron en esta ocasión «Jornadas antropológicas» reservadas a los que la América segregacionista del momento consideraba como primitivos. El impacto de los estudios sobre las razas, sobre la manera de pensar en el deporte no fue, al contrario de lo que se esforzaron hacer creer los diferentes presidentes del C.O.I en el curso de las siguientes decadas, un simple avatar del movimiento olimpico. Veremos la influencía de este espectáculo atletico interracial en los Estados Unidos pero tambien en el mundo, particularmente a través del papel de la prensa. Las jornadas antropológicas permitieron indudablemente elaborar una cierta percepción de la otricidad y limitaran la integración de los pueblos autóctonas en la maquina deportiva mundial.
Louis Pasteur, the father of immunology?
Directory of Open Access Journals (Sweden)
Kendall A Smith
2012-04-01
Full Text Available Louis Pasteur is traditionally considered as the progenitor of modern immunology because of his studies in the late 19th century that popularized the germ theory of disease, and that introduced the hope that all infectious diseases could be prevented by prophylactic vaccination, as well as also treated by therapeutic vaccination, if applied soon enough after infection. However, Pasteur was working at the dawn of the appreciation of the microbial world, at a time when the notion of such a thing as an immune system did not exist, certainly not as we know it today, more than 130 years later. Accordingly, why was Pasteur such a genius as to discern how the immune system functions to protect us against invasion by the microbial world when no one had even made the distinction between fungi, bacteria or viruses, and no one had formulated any theories of immunity. A careful reading of Pasteur’s presentations to the Academy of Sciences reveals that Pasteur was entirely mistaken as to how immunity occurs, in that he reasoned, as a good microbiologist would, that appropriately attenuated microbes would deplete the host of vital trace nutrients absolutely required for their viability and growth, and not an active response on the part of the host. Even so, he focused attention on immunity, preparing the ground for others who followed. This review chronicles Pasteur’s remarkable metamorphosis from organic chemist to microbiologist to immunologist, and from basic science to medicine.
Louis Aragon y el quotidien merveilleux surrealista
Directory of Open Access Journals (Sweden)
Camilo Hoyos Gómez
2013-01-01
Full Text Available El artículo propone un análisis de la mirada y de la imaginación en el paseo urbano por el parisino Pasaje de la Ópera narrado en El campesino de París , de Louis Aragon. En este texto se propone un conocimiento sensible del mundo que parte de la experiencia de lo concreto. De esta manera, el conocimiento de lo concreto y un nuevo acercamiento sobre el mundo circundante le permiten a Aragon desarrollar la teoría del quotidien merveilleux , que consiste en la posibilidad de contemplar imágenes provenientes de la imaginación e impulsadas por el contacto con lo real. A partir de la importancia de la mirada en la ciudad, Aragon establece una nueva epistemología de la mirada, puesto que determina la “lluvia de imágenes” que provienen de un espacio interior de quien camina la ciudad. Este texto, uno de los primeros y fundamentales libros del surrealismo, es una apología de la ciudad y del conocimiento sensorial del mundo y parte de la experienc ia en la ciudad como lugar mágico y cotidiano.
Louis pasteur, the father of immunology?
Smith, Kendall A
2012-01-01
Louis Pasteur is traditionally considered as the progenitor of modern immunology because of his studies in the late nineteenth century that popularized the germ theory of disease, and that introduced the hope that all infectious diseases could be prevented by prophylactic vaccination, as well as also treated by therapeutic vaccination, if applied soon enough after infection. However, Pasteur was working at the dawn of the appreciation of the microbial world, at a time when the notion of such a thing as an immune system did not exist, certainly not as we know it today, more than 130 years later. Accordingly, why was Pasteur such a genius as to discern how the immune system functions to protect us against invasion by the microbial world when no one had even made the distinction between fungi, bacteria, or viruses, and no one had formulated any theories of immunity. A careful reading of Pasteur's presentations to the Academy of Sciences reveals that Pasteur was entirely mistaken as to how immunity occurs, in that he reasoned, as a good microbiologist would, that appropriately attenuated microbes would deplete the host of vital trace nutrients absolutely required for their viability and growth, and not an active response on the part of the host. Even so, he focused attention on immunity, preparing the ground for others who followed. This review chronicles Pasteur's remarkable metamorphosis from organic chemist to microbiologist to immunologist, and from basic science to medicine.
Schroedinger vs. Navier–Stokes
Directory of Open Access Journals (Sweden)
P. Fernández de Córdoba
2016-01-01
Full Text Available Quantum mechanics has been argued to be a coarse-graining of some underlying deterministic theory. Here we support this view by establishing a map between certain solutions of the Schroedinger equation, and the corresponding solutions of the irrotational Navier–Stokes equation for viscous fluid flow. As a physical model for the fluid itself we propose the quantum probability fluid. It turns out that the (state-dependent viscosity of this fluid is proportional to Planck’s constant, while the volume density of entropy is proportional to Boltzmann’s constant. Stationary states have zero viscosity and a vanishing time rate of entropy density. On the other hand, the nonzero viscosity of nonstationary states provides an information-loss mechanism whereby a deterministic theory (a classical fluid governed by the Navier–Stokes equation gives rise to an emergent theory (a quantum particle governed by the Schroedinger equation.
Navier Stokes Theorem in Hydrology
Narayanan, M.
2005-12-01
In a paper presented at the 2004 AGU International Conference, the author outlined and stressed the importance of studying and teaching certain important mathematical techniques while developing a course in Hydrology and Fluid Mechanics. The Navier-Stokes equations are the foundation of fluid mechanics, and Stokes' theorem is used in nearly every branch of mechanics as well as electromagnetics. Stokes' Theorem also plays a vital role in many secondary theorems such as those pertaining to vorticity and circulation. Mathematically expressed, Stokes' theorem can be expressed by considering a surface S having a bounding curve C. Here, V is any sufficiently smooth vector field defined on the surface and its bounding curve C. In an article entitled "Corrections to Fluid Dynamics" R. F. Streater, (Open Systems and Information Dynamics, 10, 3-30, 2003.) proposes a kinetic model of a fluid in which five macroscopic fields, the mass, energy, and three components of momentum, are conserved. The dynamics is constructed using the methods of statistical dynamics, and results in a non-linear discrete-time Markov chain for random fields on a lattice. In the continuum limit he obtains a non-linear coupled parabolic system of field equations, showing a correction to the Navier-Stokes equations. In 2001, David Hoff published an article in Journees Equations aux derivees partielles. (Art. No. 7, 9 p.). His paper is entitled : Dynamics of Singularity Surfaces for Compressible Navier-Stokes Flows in Two Space Dimensions. In his paper, David Hoff proves the global existence of solutions of the Navier-Stokes equations of compressible, barotropic flow in two space dimensions with piecewise smooth initial data. These solutions remain piecewise smooth for all time, retaining simple jump discontinuities in the density and in the divergence of the velocity across a smooth curve, which is convected with the flow. The strengths of these discontinuities are shown to decay exponentially in time
Stokes solitons in optical microcavities
Yang, Qi-Fan; Yi, Xu; Yang, Ki Youl; Vahala, Kerry
2017-01-01
Solitons are wave packets that resist dispersion through a self-induced potential well. They are studied in many fields, but are especially well known in optics on account of the relative ease of their formation and control in optical fibre waveguides. Besides their many interesting properties, solitons are important to optical continuum generation, in mode-locked lasers, and have been considered as a natural way to convey data over great distances. Recently, solitons have been realized in microcavities, thereby bringing the power of microfabrication methods to future applications. This work reports a soliton not previously observed in optical systems, the Stokes soliton. The Stokes soliton forms and regenerates by optimizing its Raman interaction in space and time within an optical potential well shared with another soliton. The Stokes and the initial soliton belong to distinct transverse mode families and benefit from a form of soliton trapping that is new to microcavities and soliton lasers in general. The discovery of a new optical soliton can impact work in other areas of photonics, including nonlinear optics and spectroscopy.
Genetic variation of St. Louis encephalitis virus.
May, Fiona J; Li, Li; Zhang, Shuliu; Guzman, Hilda; Beasley, David W C; Tesh, Robert B; Higgs, Stephen; Raj, Pushker; Bueno, Rudy; Randle, Yvonne; Chandler, Laura; Barrett, Alan D T
2008-08-01
St. Louis encephalitis virus (SLEV) has been regularly isolated throughout the Americas since 1933. Previous phylogenetic studies involving 62 isolates have defined seven major lineages (I-VII), further divided into 14 clades. In this study, 28 strains isolated in Texas in 1991 and 2001-2003, and three older, previously unsequenced strains from Jamaica and California were sequenced over the envelope protein gene. The inclusion of these new sequences, and others published since 2001, has allowed better delineation of the previously published SLEV lineages, in particular the clades of lineage II. Phylogenetic analysis of 106 isolates identified 13 clades. All 1991 and 2001-2003 isolates from Nueces, Jefferson and Harris Counties (Texas Gulf Coast) group in clade IIB with other isolates from these counties isolated during the 1980s and 1990s. This lack of evidence for introduction of novel strains into the Texas Gulf Coast over a long period of time is consistent with overwintering of SLEV in this region. Two El Paso isolates, both from 2002, group in clade VA with recent Californian isolates from 1998-2001 and some South American strains with a broad temporal range. Overall, these data are consistent with multiple introductions of SLEV from South America into North America, and provide support for the hypothesis that in most situations, SLEV circulates within a locality, with occasional incursions from other areas. Finally, SLEV has much lower nucleotide (10.1 %) and amino acid variation (2.8 %) than other members of the Japanese encephalitis virus complex (maximum variation 24.6 % nucleotide and 11.8 % amino acid).
Directory of Open Access Journals (Sweden)
Marcelo de Almeida Medeiros
2008-01-01
Full Text Available Com o intuito de contribuir para o alargamento do espectro de autores não anglófonos na literatura de Ciência Política do Brasil, o presente texto visa a (revisitar a questão da Democracia e do Regionalismo em Jean-Louis Quermonne. Ele está constituído de três partes. A primeira situa o autor no cenário da ciência política francesa através de expedita biografia. A segunda promove uma análise crítica e comparativa dos trabalhos de Quermonne que versam sobre a temática da Democracia, a saber: O governo da França sob a República, Os regimes políticos ocidentais e As políticas institucionais. A terceira parte procura estudar, também crítica e comparativamente, o pensamento de Quermonne no que toca a problemática do Regionalismo: O sistema político da União Européia, A Europa e o federalismo e A Europa em busca de legitimidade. Finalmente, o artigo traz algumas reflexões conclusivas apontando a importância do pensamento político francês em geral e de Jean-Louis Quermonne, em particular, para a ciência política contemporânea.Aiming at the development of the study of non-anglophone authors in the Political Science literature in Brazil, this text seeks to approach the issues of both Democracy and Regionalism in Jean-Louis Quermonne's bibliography. It has three parts. The first situates the author in the French political science scenario through a brief biography. The second part promotes a critical and comparative analysis of Quemonne's works on Democracy , i.e.: Le Gouvernement de la France sous la Vème République, Les régimes politiques occidentaux and Les politiques institutionnelles. The third part inquires, also critically and comparatively, about Quermonne's thinking on Regionalism: Le système politique de l'Union Européenne, L'Europe et le fédéralisme and L'Europe en quête de légitimité. Finally, this article brings some conclusive considerations, pointing out both the importance of the French, in general
The Navier-Stokes Equations II
Masuda, Kyûya; Rautmann, Reimund; Solonnikov, Vsevolod
1992-01-01
V.A. Solonnikov, A. Tani: Evolution free boundary problem for equations of motion of viscous compressible barotropic liquid.- W. Borchers, T. Miyakawa:On some coercive estimates for the Stokes problem in unbounded domains.- R. Farwig, H. Sohr: An approach to resolvent estimates for the Stokes equations in L(q)-spaces.- R. Rannacher: On Chorin's projection method for the incompressible Navier-Stokes equations.- E. S}li, A. Ware: Analysis of the spectral Lagrange-Galerkin method for the Navier-Stokes equations.- G. Grubb: Initial value problems for the Navier-Stokes equations with Neumann conditions.- B.J. Schmitt, W. v.Wahl: Decomposition of solenoidal fields into poloidal fields, toroidal fields and the mean flow. Applications to the Boussinesq-equations.- O. Walsh: Eddy solutions of the Navier-Stokesequations.- W. Xie: On a three-norm inequality for the Stokes operator in nonsmooth domains.
Pasicki, Lech
2011-01-01
Many versions of the Stokes theorem are known. More advanced of them require complicated mathematical machinery to be formulated which discourages the users. Our theorem is sufficiently simple to suit the handbooks and yet it is pretty general, as we assume the differential form to be continuous on a compact set F(A) and C1 "inside" while F(A) is built of "bricks" and its inner part is a C1 manifold. There is no problem of orientability and the integrals under consideration are convergent. The proof is based on integration by parts and inner approximation.
Marketingová analýza hotelu Louis Leger
Řehák, Vojtěch
2013-01-01
This bachelor thesis deals with analysis of the marketing strategy of the hotel Louis Leger. The main goal of the thesis is to evaluate this strategy and alternatively to suggest specific changes. First part of the thesis is aimed at the theory of internet marketing, marketing mix and SWOT analysis. In the second part there are information about the company Czech Inn Hotels and the hotel Louis Leger. In the next part there is the analysis itself, which took place on the basis of the data from...
Collinear and noncollinear emission of anti-stokes and second order stokes Raman radiation
Aussenegg, F. R.; Lippitsch, M. E.; Brandmüller, J.; Nitsch, W.
1981-04-01
Generating higher order stimulated Raman scattering in benzene, apart from phase-matched anti-Stokes radiation a collinear anti-Stokes emission is observed, which is explained by parametric four-photon processes under mismatch condition.
Accuracy of Stokes integration for geoid computation
Ismail, Zahra; Jamet, Olivier; Altamimi, Zuheir
2014-05-01
Geoid determination by remove-compute-restore (RCR) technique involves the application of Stokes's integral on reduced gravity anomalies. Reduced gravity anomalies are obtained through interpolation after removing low degree gravity signal from space spherical harmonic model and high frequency from topographical effects and cover a spectre ranging from degree 150-200. Stokes's integral is truncated to a limited region around the computation point producing an error that will be reducing by a modification of Stokes's kernel. We study Stokes integral accuracy on synthetic signal of various frequency ranges, produced with EGM2008 spherical harmonic coefficients up to degree 2000. We analyse the integration error according to the frequency range of signal, the resolution of gravity anomaly grid and the radius of Stokes integration. The study shows that the behaviour of the relative errors is frequency independent. The standard Stokes kernel is though insufficient to produce 1cm geoid accuracy without a removal of the major part of the gravity signal up to degree 600. The Integration over an area of radius greater than 3 degree does not improve accuracy improvement. The results are compared to a similar experiment using the modified Stokes kernel formula (Ellmann2004, Sjöberg2003). References: Ellmann, A. (2004) The geoid for the Baltic countries determined by least-squares modification of Stokes formula. Sjöberg, LE (2003). A general model of modifying Stokes formula and its least-squares solution Journal of Geodesy, 77. 459-464.
General Revenue Sharing in St. Louis City and County.
Wilkinson, Etta Lou; Barnett, Malcolm Joel
Unlike typical Federal catergorical grants which are highly specific, General Revenue Sharing grants (GRS) are free of restrictions or conditions. The Missouri Advisory Committee, in viewing the impact of GRS on St. Louis City and County, received evidence regarding: (1) the nature of GRS-funded expenditures; (2) the limits of citizen…
Toward Voluntary Desegregation: The Beginnings of the St. Louis Plan.
Foote, Edward T. II
1988-01-01
The human drama in beginning St. Louis's desegregation plan is presented. As the chair of a citizen's committee, the author worked with the superintendent and the Board of Education to create a plan. Implementation was accomplished in a few months. The desegregation of suburban districts was settled in court. (VM)
Biography of louis braille and invention of the braille alphabet.
Jiménez, Javier; Olea, Jesús; Torres, Jesús; Alonso, Inmaculada; Harder, Dirk; Fischer, Konstanze
2009-01-01
Louis Braille (1809-1852) was born in France. At the age of three, he wounded his right eye with a cobbler's tool while playing in his father's workshop. No medical knowledge could save his eyesight at that time. Louis's left eye became inflamed, apparently due to subsequent sympathetic ophthalmia, and he eventually lost the sight in that eye. At the age of five, Louis Braille was completely blind. He is considered to be the inventor of a writing system by touch that bears his name, the Braille system. This revolutionary system has allowed blind people to access written culture, and it can therefore be considered a major advance in the quality of life for the blind. The immediate precursor of the invention of the Braille system was the alphabet created by Charles Barbier de la Serre (1767-1841) who created a language by touch designed for military and secret use. Louis Braille modified this alphabet into the Braille alphabet, which is practically the same one that is currently used. It required time to be recognized and to be implemented as a reading and writing method for blind people throughout the world. In 1950, UNESCO effectively universalized the Braille alphabet, and in 2005 it recognized Braille system as a "vital language of communication, as legitimate as all other languages in the world."
Kuressaares tulevad Louis Kahni päevad
2006-01-01
Eesti Arhitektide Liit korraldab 6.-7.okt. 2006 rahvusvahelise arhitektuurikonverentsi ja näituse Saaremaalt pärit arhitekti Louis Kahni loomingust. Kuressaare raekotta pannakse üles Kahni portree, autoriks tema tütar Alexandra Tyng
Kus sündis Louis Kahn? / Olavi Pesti
Pesti, Olavi, 1950-
2006-01-01
Eesti päritolu ameerika arhitekti Louis Kahni (sünd. Itze-Leib Schmuilowsky) perekonnalugu. 6.-7. okt. 2006. a. Kuressaares toimuvatest Kahni päevadest, küsimustele vastab peakorraldaja Ingrid Mald-Villand
Louis Isidore Kahni jäljed Saaremaal / Mark Soosaar
Soosaar, Mark, 1946-
2006-01-01
Eesti päritolu ameerika arhitektist Louis Kahnist, tema mälestuse jäädvustamisest. Le Corbusier'i ja Kahni loomingut meenutavatest majadest Kuressaares. Kuressaare elektrijaamast, mis ehitati töödejuhataja Aleksei Võrgu jooniste järgi. Kommentaar Mart Kalmult
Louis Isidore Kahni jäljed Saaremaal / Mark Soosaar
Soosaar, Mark, 1946-
2006-01-01
Eesti päritolu ameerika arhitektist Louis Kahnist, tema mälestuse jäädvustamisest. Le Corbusier'i ja Kahni loomingut meenutavatest majadest Kuressaares. Kuressaare elektrijaamast, mis ehitati töödejuhataja Aleksei Võrgu jooniste järgi. Kommentaar Mart Kalmult
Kus sündis Louis Kahn? / Olavi Pesti
Pesti, Olavi, 1950-
2006-01-01
Eesti päritolu ameerika arhitekti Louis Kahni (sünd. Itze-Leib Schmuilowsky) perekonnalugu. 6.-7. okt. 2006. a. Kuressaares toimuvatest Kahni päevadest, küsimustele vastab peakorraldaja Ingrid Mald-Villand
Eli Fischer-Jørgensen, Eugeniu Coseriu et Louis Hjelmslev
DEFF Research Database (Denmark)
Jensen, Viggo Bank
2015-01-01
Based on a correspondence between Eugenio Coseriu (1921-2002) and Eli Fischer-Jørgensen (1911-2010), the article discusses the importance of Louis Hjelmslev (1899-1965) for the development of the theory of Coseriu. In a letter dated 1955, Fischer-Jørgensen agrees with Coseriu in his criticism of ...
Phenology of larval fish in the St. Louis River estuary
Little work has been done on the phenology of fish larvae in Great Lakes coastal wetlands. As part of an aquatic invasive species early detection study, we conducted larval fish surveys in the St. Louis River estuary (SLRE) in 2012 and 2013. Using multiple gears in a spatially ba...
Conceptualising Childhood: Robert Louis Stevenson's "A Child's Garden of Verses."
Webb, Jean
2002-01-01
Discusses the construct of childhood in Robert Louis Stevenson's collection of poems, "A Child's Garden of Verses," by employing notions of child development drawn from Jean Piaget and Lev Vygotsky. Finds, from a literary perspective, Stevenson's collection located on the boundaries of romanticism and modernism. (BT)
Louis J. Lanzerotti receives 2011 William Bowie Medal: Citation
Baker, Daniel N.; Kennel, Charles F.
2012-01-01
Louis J. Lanzerotti was awarded the 2011 William Bowie Medal at the AGU Fall Meeting Honors Ceremony, held on 7 December 2011 in San Francisco, Calif. The medal is for “outstanding contributions to fundamental geophysics and for unselfish cooperation in research.”
Louis J. Lanzerotti receives 2011 William Bowie Medal: Response
Lanzerotti, Louis J.
2012-01-01
Louis J. Lanzerotti was awarded the 2011 William Bowie Medal at the AGU Fall Meeting Honors Ceremony, held on 7 December 2011 in San Francisco, Calif. The medal is for “outstanding contributions to fundamental geophysics and for unselfish cooperation in research.”
Conceptualising Childhood: Robert Louis Stevenson's "A Child's Garden of Verses."
Webb, Jean
2002-01-01
Discusses the construct of childhood in Robert Louis Stevenson's collection of poems, "A Child's Garden of Verses," by employing notions of child development drawn from Jean Piaget and Lev Vygotsky. Finds, from a literary perspective, Stevenson's collection located on the boundaries of romanticism and modernism. (BT)
A Conservation with...Henry Louis Gates, Jr.
Cheney, Lynne V.
1991-01-01
Presents an interview between National Endowment for the Humanities chairman, Lynne V. Cheney, and Harvard professor, Henry Louis Gates, Jr. Includes discussion of multiculturalism as it relates to free speech, sexism, racism, hate speech, and ethnocentrism. Emphasizes both the open tradition of Western culture and the recent pressure for…
Annual Convention in St. Louis: A Dynamic Convergence
Emeagwali, N. Susan
2012-01-01
Nearly 3,000 career and technical educators from across the country converged upon St. Louis, Missouri, for the premier professional development event in career and technical education (CTE). The Association for Career and Technical Education (ACTE) held its Annual Convention and Career Tech Expo November 17-19, bringing together teachers,…
Restructuring through Community Education: The St. Louis Model.
Nance, Everette E.; Windom, John
1995-01-01
St. Louis Public Schools established 15 community education centers to provide comprehensive educational services, changing the way administrators and staff operate. The program had to overcome resistance to change, ensure that mission and purpose were understood by all, recognize that change and trust take time, and deal with differences that may…
School Food Environment of Charter Schools in St. Louis
Linsenmeyer, Whitney; Kelly, Patrick; Jenkins, Steve; Mattfeldt-Berman, Mildred
2013-01-01
Purpose/Objectives: The purpose of this study was to explore the school food environment of charter schools in Saint Louis, Missouri. The objectives were to: (1) describe the participation of charter schools in the National School Lunch Program and (2) describe the prevalence of competitive foods in charter schools. Methods: School administrators…
Obituary: John Louis Perdrix, 1926-2005
Orchiston, D. Wayne
2006-12-01
John Perdrix, astronomical historian and co-founder of the Journal of Astronomical History and Heritage, died on 27 June 2005. John Louis Perdrix was born in Adelaide, Australia, on 30 June 1926. After studying chemistry at Melbourne Technical College and working in industry, he joined the Commonwealth Scientific and Industrial Research Organisation's Division of Minerals and Geochemistry. In 1974 the Division relocated to the Western Australian capital, Perth, and John spent the rest of his working life there involved in geochemical research. From his teenage years John had a passion for astronomy, which he fine-tuned through the Astronomical Society of Victoria and the Victorian Branch of the British Astronomical Association. He was very active in both groups, serving as President of the former and Secretary/Treasurer of the latter. He was also an FRAS, and a member of the AAS, the BAA parent body, and the IAU (Commission 41)?no mean feat for an Australian amateur astronomer. Throughout his life, he was a strong advocate of close amateur-professional relations. John's main research interest was history of astronomy, and over the years he wrote a succession of research papers, mainly about aspects of Australian astronomy. His well-researched and neatly-illustrated papers on the Melbourne Observatory and the Great Melbourne Telescope are classics, and when the Observatory's future was in the balance they played a key role in the State Government's decision to convert this unique facility into a museum precinct. To support his research activities, John built up an amazing library that developed its own distinctive personality and quickly took over his house and garage before invading commercial storage facilities! Apart from writing papers, John had an even greater passion for editing and publishing. From 1985 to 1997 he produced the Australian Journal of Astronomy, and in 1998 this was replaced by the Journal of Astronomical History and Heritage (JAH2). Both
Unsteady Stokes Equations: Some Complete General Solutions
Indian Academy of Sciences (India)
A Venkatlaxmi; B S Padmavathi; T Amaranath
2004-05-01
The completeness of solutions of homogeneous as well as non-homogeneous unsteady Stokes equations are examined. A necessary and sufficient condition for a divergence-free vector to represent the velocity field of a possible unsteady Stokes flow in the absence of body forces is derived.
Interpolating function and Stokes Phenomena
Honda, Masazumi
2015-01-01
When we have two expansions of physical quantity around two different points in parameter space, we can usually construct a family of functions, which interpolates the both expansions. In this paper we study analytic structures of such interpolating functions and discuss their physical implications. We propose that the analytic structures of the interpolating functions provide information on analytic property and Stokes phenomena of the physical quantity, which we approximate by the interpolating functions. We explicitly check our proposal for partition functions of zero-dimensional $\\varphi^4$ theory and Sine-Gordon model. In the zero dimensional Sine-Gordon model, we compare our result with a recent result from resurgence analysis. We also comment on construction of interpolating function in Borel plane.
Generalized Stokes vector for three photon process
Shaji, Chitra; Satyanarayana, SVM; Sharan, Alok
2015-01-01
Stokes Muller formalism is important to understand the optical properties of materials by measuring the change in the polarization state of light upon scattering. The formalism can be extended to nonlinear scattering processes involving two and three photon processes. In this work, we derive a triple Stokes vector analytically using operator approach used in quantum theory of light. A three photon polarization state can be described by Stokes vector that has sixteen components involving cubes of intensities. The response of a material for the scattering of light in a three photon process is described by 4 x 16 Muller matrix. Polarization in Polarization out (PIPO) experiments can be carried out to determine the elements of Muller matrix. For that we identify 16 independent points in Poincare sphere and construct triple Stokes vector for each point. Four measurements to find the linear Stokes vector of the scattered light for incident light in each of the sixteen three photon states determine the Muller matrix...
St. Louis FUSRAP-A Strategy for Success
Energy Technology Data Exchange (ETDEWEB)
Lyerla, M.; Fox, B.; Chinnock, J.; Haase, A.; Wojinski, S.; Bretz, M.; Cotner, S.; Dellorco, L.; Mueller, D.; Roberts, S.; Overmohle, D.
2002-02-27
In October 1997, Congress transferred the Formerly Utilized Sites Remedial Action Program (FUSRAP) from the Department of Energy (DOE) to the United States Army Corps of Engineers (USACE). FUSRAP addresses contamination generated by activities of the Manhattan Engineering District and the Atomic Energy Commission during the 1940's and 50's in support of the nation's nuclear weapons development program. The USACE Operation Order for FUSRAP gave responsibility for remediation of five sites in Missouri and Illinois to the USACESt. Louis District. The principal site is the St. Louis Airport Site (SLAPS), which involves the removal, transportation, disposal, and restoration of approximately 28 acres and 245,000 bank cubic yards (bcy) of contaminated soils. This paper will focus on the progress and achievements in removal action efficiencies of the SLAPS team. This team consists primarily of the USACE and Stone & Webster, Incorporated.
Louis Pasteur (1822-1895)--chance and the prepared mind.
Manchester, K L
1995-12-01
Louis Pasteur is often regarded as one of the founders of microbiology, and is chiefly famous for his discovery of the role that microorganisms play in health and disease. However, he was trained as a physical scientist, and his research began with the discovery of the stereoisomerism of the different forms of tartaric acid. As a biotechnologist, he is remembered for his studies on the nature of fermentation, and for his rebuttal of the theory of spontaneous generation.
[The oral health problems of Sun King Louis XIV].
Eijkman, M A J
2012-01-01
King Louis XIV (1638-1715) of France was a man plagued by a variety of chronic diseases, such as rheumatism, intestinal infections, fistula, headaches, chronic fever, malaria, urinary infections, gout, and chronic oral problems. At his birth, 2 deciduous teeth were already erupted, and at a very young age he already suffered from caries. In 1685, when he revoked the Edict of Nantes, a clumsy extraction of all maxillary teeth gave rise to a large maxillary bone defect and an oroantral communication.
Louis Kahni Päevad Kuressaares / Ingrid Mald-Villand
Mald-Villand, Ingrid
2006-01-01
6.-7. oktoobril toimunud üritustest, millega tähistati arhitekt Louis Kahni 105. sünniaastapäeva ja eesti inseneri August Komendanti 100. sünniaastapäeva. 6. oktoobril alustati arhitekti portree avamisega, mille oli maalinud tütar Alexandra Tyng, sama päeva õhtul avati näitus Kahni loomingust Kuressaare lossis ja linnateatris esitleti Nathaniel Kahni dokumentaalfilmi "My architect". 7. oktoobril peeti rahvusvaheline arhitektuurikonverents
Louis Kahni Päevad Kuressaares / Ingrid Mald-Villand
Mald-Villand, Ingrid
2006-01-01
6.-7. oktoobril toimunud üritustest, millega tähistati arhitekt Louis Kahni 105. sünniaastapäeva ja eesti inseneri August Komendanti 100. sünniaastapäeva. 6. oktoobril alustati arhitekti portree avamisega, mille oli maalinud tütar Alexandra Tyng, sama päeva õhtul avati näitus Kahni loomingust Kuressaare lossis ja linnateatris esitleti Nathaniel Kahni dokumentaalfilmi "My architect". 7. oktoobril peeti rahvusvaheline arhitektuurikonverents
Balzac's Louis Lambert : schizophrenia before Kraepelin and Bleuler.
Dieguez, Sebastian
2013-01-01
Honoré de Balzac (1799-1850) is well known for his penetrating observations and descriptions of the burgeoning social life and emerging modernity of 19th century France. This chapter focuses on the novel Louis Lambert, first published in 1832. It is argued that its main character provides the first complete and convincing description of schizophrenia - 69 years before Kraepelin fully developed the concept of dementia praecox and 76 years before Bleuler coined the word 'schizophrenia'. We consider the history of the concept of schizophrenia and the intriguing possibility that it is a recent disease. Indeed, if schizophrenia had always existed, it would seem odd that Balzac's novel should be the very first convincing and complete literary account of the disease. This claim is examined by a thorough description of Louis Lambert's symptoms as they appear in the text, and compared to other claims of priority (namely, Shakespeare's King Lear and Gogol's Diary of a Madman). The chapter also provides some background on Balzac's relationship with mysticism, mental illness, and the world of psychiatry. We conclude with remarks regarding influences of Louis Lambert, the case for the priority of the novel as the princeps case of schizophrenia, and its relevance to the recency hypothesis of schizophrenia. Copyright © 2013 S. Karger AG, Basel.
GASP-Galway astronomical Stokes polarimeter
Kyne, G.; Sheehan, B.; Collins, P.; Redfern, M.; Shearer, A.
2010-06-01
The Galway Astronomical Stokes Polarimeter (GASP) is an ultra-high-speed, full Stokes, astronomical imaging polarimeter based upon a Division of Amplitude Polarimeter. It has been developed to resolve extremely rapid stochastic (~ms) variations in objects such as optical pulsars, magnetars and magnetic cataclysmic variables. The polarimeter has no moving parts or modulated components so the complete Stokes vector can be measured from just one exposure - making it unique to astronomy. The time required for the determination of the full Stokes vector is limited only by detector efficiency and photon fluxes. The polarimeter utilizes a modified Fresnel rhomb that acts as a highly achromatic quarter wave plate and a beamsplitter (referred to as an RBS). We present a description of how the DOAP works, some of the optical design for the polarimeter. Calibration is an important and difficult issue with all polarimeters, but particularly in astronomical polarimeters. We give a description of calibration techniques appropriate to this type of polarimeter.
Homogenizing the Darcy/Stokes coupling
Gruais, Isabelle; Polisevski, Dan
2011-01-01
We study a fluid flow traversing a porous medium and obeying the Darcy's law in the case when this medium is fractured by a periodical distribution of fissures filled with a Stokes fluid. These two flows are coupled by a Beavers-Joseph type interface condition. As the small period of the distribution shrinks to zero, the resulting asymptotic behaviour is implicitely described by two underlying macroscopic quantities: the limit of the Stokes velocity and the limit of the Darcy pressure, soluti...
Stokes and anti-stokes stimulated Mie scattering on nanoparticle suspensions of latex
Burkhanov, I. S.; Krivokhizha, S. V.; Chaikov, L. L.
2016-12-01
Stokes and anti-Stokes shifts of stimulated concentration light scattering (SCLS, stimulated Mie scattering) in suspensions of various-sized latex nanoparticles in water were measured by the light guide scheme, under conditions of backscattering in the presence of convection.
On the Coupling of Incompressible Stokes or Navier–Stokes and Darcy Flows Through Porous Media
Girault, V.
2012-11-03
In this chapter, we present the theoretical analysis of coupled incompressible Navier-Stokes (or Stokes) flows and Darcy flows with the Beavers-Joseph-Saffman interface condition. We discuss alternative interface and porous media models. We review some finite element methods used by several authors in this coupling and present numerical experiments.
Stokes efficiency and its stochastic properties
Sahoo, Mamata; Jayannavar, A. M.
2017-01-01
We study the Stokes efficiency and its fluctuating properties in the case of a spatial asymmetric ratchet potential with a temporal asymmetric driving force from adiabatic to nonadiabatic regime. Our numerical investigations show that the average Stokes efficiency and the average current decrease with increase in the frequency of driving. For low frequency of driving, i.e., in the case of an adiabatic regime, we reproduced the analytical results supporting our numerical simulations. By evaluating the probability distribution p(ηs) for Stokes efficiency ηs, we focus on the stochastic properties of Stokes efficiency. We find that in most of the parameter space, fluctuations in ηs are comparable to or larger than the mean values. In such a situation, one has to study the nature of the full probability distribution of ηs. We observe that with increase in frequency of driving, the distribution becomes multipeaked. At the same time, the average Stokes efficiency monotonically decreases with increase in frequency of the drive. For high frequency of driving, the distribution develops a peak at zero. With further increase in frequency of the drive this peak gets sharper. And finally at sufficiently high frequency, we get a strong peak at zero indicating that there is no effective transport in this regime.
Louis Aragon: (Re writing the Nazi-Soviet Pact
Directory of Open Access Journals (Sweden)
Angela KIMYONGÜR
2006-10-01
Full Text Available At the time of the Nazi-Soviet non-aggression pact of 1939, Louis Aragon was a member of the French Communist Party (PCF, a well known novelist and poet and a journalist. Whilst his writing career had undergone several notable transformations, not least that from surrealist to socialist realist, his political commitment to the left and, from 1927 to the PCF, remained steadfast for much of his life. Indeed, unlike the PCF’s interpretation of the Second World War, which underwent a number of s...
Did Robert Louis Stevenson have hereditary hemorrhagic telangiectasia?
Guttmacher, A E; Callahan, J R
2000-03-06
Chronic illness played a major role in the life and literary success of Robert Louis Stevenson. However, the exact nature of his chronic illness remains unclear. It is possible that Stevenson had hereditary hemorrhagic telangiectasia (Osler-Rendu-Weber Syndrome). This would explain his chronic respiratory complaints, recurrent episodes of pulmonary hemorrhage, and his death, at age 44 years, of probable cerebral hemorrhage. It would also explain his mother's hitherto unreported but apparent stroke, at age 38 years. Further support for this hypothesis might come from new details about the health of Stevenson and his relatives or from molecular analysis of tissue specimens remaining from him.
The Classical Version of Stokes' Theorem Revisited
DEFF Research Database (Denmark)
Markvorsen, Steen
2005-01-01
Using only fairly simple and elementary considerations - essentially from first year undergraduate mathematics - we prove that the classical Stokes' theorem for any given surface and vector field in $\\mathbb{R}^{3}$ follows from an application of Gauss' divergence theorem to a suitable modification...... of the vector field in a tubular shell around the given surface. The intuitive appeal of the divergence theorem is thus applied to bootstrap a corresponding intuition for Stokes' theorem. The two stated classical theorems are (like the fundamental theorem of calculus) nothing but shadows of the general version...... to above. Our proof that Stokes' theorem follows from Gauss' divergence theorem goes via a well known and often used exercise, which simply relates the concepts of divergence and curl on the local differential level. The rest of the paper uses only integration in $1$, $2$, and $3$ variables together...
2013-08-29
... Paperwork Reduction Act (44 U.S.C. 3501 et seq.); is certified as not having a significant economic impact... include amendments to sections (1) through (4) of rule 10 CSR 10-5.480 St. Louis Area Transportation... approving the State's request to amend 10 CSR 10-5.480 St. Louis Area Transportation Conformity Requirements...
Geeniuste tagasitulek : Louis Kahni päevad Kuressaares / Toivo Tammik
Tammik, Toivo
2006-01-01
6. X avatakse Louis Kahni portree Kuressaare raekojas ja näitus Kuressaare linnuses, Kuressaare Linnateatris linastub arhitekti poja Nathaniel Kahni film "My architect. Son's journey" (2003). 7. X toimuva rahvusvahelise arhitektuurikonverentsi kava. 1956. a. Philadelphias kohtunud Saaremaal sündinud Louis Isadore Kahnist ja Järvamaal sündinud August Eduard Komendandist
Geeniuste tagasitulek : Louis Kahni päevad Kuressaares / Toivo Tammik
Tammik, Toivo
2006-01-01
6. X avatakse Louis Kahni portree Kuressaare raekojas ja näitus Kuressaare linnuses, Kuressaare Linnateatris linastub arhitekti poja Nathaniel Kahni film "My architect. Son's journey" (2003). 7. X toimuva rahvusvahelise arhitektuurikonverentsi kava. 1956. a. Philadelphias kohtunud Saaremaal sündinud Louis Isadore Kahnist ja Järvamaal sündinud August Eduard Komendandist
33 CFR 165.T09-0124 - Safety Zone; St. Louis River, Tallas Island, Duluth, MN.
2010-07-01
... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone; St. Louis River, Tallas Island, Duluth, MN. 165.T09-0124 Section 165.T09-0124 Navigation and Navigable Waters COAST GUARD... § 165.T09-0124 Safety Zone; St. Louis River, Tallas Island, Duluth, MN. (a) Location. The following area...
75 FR 24402 - Safety Zone; St. Louis River, Tallas Island, Duluth, MN
2010-05-05
... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; St. Louis River, Tallas Island, Duluth, MN....T09-0124 Safety Zone; St. Louis River, Tallas Island, Duluth, MN (a) Location. The following area is a...
Resources for Economic Educators from the Federal Reserve Bank of St. Louis
Suiter, Mary C.; Taylor, Keith G.
2016-01-01
The Federal Reserve Bank of St. Louis has a long history of providing economic and financial information to the public that continues today, although the format, delivery, and amount of information have changed over the years. Today, the St. Louis Fed provides Web-based data and information services, including FRED® and FRASER®, and publications,…
First Olin - Fudan EMBA＇s Scheduled for St. Louis Residency
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
The first 18-month EMBA program offered by Washington University in St. Louis (Olin) and Fudan University in Shanghai is quickly nearing an end. Students in the joint EMBA program, which began in April 2002, will complete their studies this fall during their residency on campus at Washington University in St. Louis.
A predictive model for floating leaf vegetation in the St. Louis River Estuary
In July 2014, USEPA staff was asked by MPCA to develop a predictive model for floating leaf vegetation (FLV) in the St. Louis River Estuary (SLRE). The existing model (Host et al. 2012) greatly overpredicts FLV in St. Louis Bay probably because it was based on a limited number of...
Muusikale meeldib olla kõikjal / Louis Andriessen ; interv. Harry Liivrand
Andriessen, Louis
2000-01-01
Hollandi heliloojast Louis Andriessenist ja tema loomingust. 19. ja 20. sajandi ooperi erinevusest. Ka 1999. a. Amsterdamis esietendunud Louis Andriesseni ja Peter Greenaway ooperist "Writing to Vermeer", mis on pühendatud Jan Vermeer van Delfti ühele elulõigule 1672. a. Kommenteerinud Harry Liivrand, Olari Elts
Seeds of Knowledge: The Evolution of the Louis Bromfield Sustainable Agriculture Library.
Miraglia, Laurie L.
The Louis Bromfield Sustainable Agriculture Library is located in Lucas, Ohio, at Malabar Farm State Park. Established in 1992, the library is jointly maintained by the Ohio State University Sustainable Agriculture Program and the Ohio Department of Agriculture. The library's namesake, Louis Bromfield, was a Pulitzer Prize-winning author and noted…
Muusikale meeldib olla kõikjal / Louis Andriessen ; interv. Harry Liivrand
Andriessen, Louis
2000-01-01
Hollandi heliloojast Louis Andriessenist ja tema loomingust. 19. ja 20. sajandi ooperi erinevusest. Ka 1999. a. Amsterdamis esietendunud Louis Andriesseni ja Peter Greenaway ooperist "Writing to Vermeer", mis on pühendatud Jan Vermeer van Delfti ühele elulõigule 1672. a. Kommenteerinud Harry Liivrand, Olari Elts
Preconditioners for Incompressible Navier-Stokes Solvers
Institute of Scientific and Technical Information of China (English)
A.Segal; M.ur Rehman; C.Vuik
2010-01-01
In this paper we give an overview of the present state of fast solvers for the solution of the incompressible Navier-Stokes equations discretized by the finite element method and linearized by Newton or Picard's method. It is shown that block precon- ditioners form an excellent approach for the solution, however if the grids are not to fine preconditioning with a Saddle point ILU matrix (SILU) may be an attractive al- ternative. The applicability of all methods to stabilized elements is investigated. In case of the stand-alone Stokes equations special preconditioners increase the efficiency considerably.
The Catholicity of the University of Saint Louis
Directory of Open Access Journals (Sweden)
Darin Jan C. Tindowen
2015-12-01
Full Text Available As it celebrates its 50th year of life of mission and excellence, the University of Saint Louis, Tuguegarao City, Northern Philippines is facing challenges posed in the education apostolate, and one of which is to uphold a good institutional image of being a truly Catholic institution. This study aimed to assess the level of Catholicity of the university along the five key area standards which are communicated vision and mission, religious curriculum, prayer and liturgy integration, service and social justice, and ecumenical initiatives as perceived by the respondents. Two thousand six hundred twenty respondents across the Louisian community were considered in the study through a descriptive survey and Focus Group Discussion. Results show that the respondent school manifests a Very High level of Catholicity along the five key area standards. Moreover, results of the independent sample T-test and Analysis of Variance test reveal that gender, religious affiliations, and student’s educational level affect the level of Catholicity of the respondent school. The study concluded that the University of Saint Louis is a Catholic institution forming and training Jesus’ disciples of today. As an offshoot of the results of the study, a three-year sustainability program for the Catholicity of the institution was developed.
GASP-Galway astronomical Stokes polarimeter
Directory of Open Access Journals (Sweden)
Shearer A.
2010-06-01
Full Text Available The Galway Astronomical Stokes Polarimeter (GASP is an ultra-high-speed, full Stokes, astronomical imaging polarimeter based upon a Division of Amplitude Polarimeter. It has been developed to resolve extremely rapid stochastic (~ms variations in objects such as optical pulsars, magnetars and magnetic cataclysmic variables. The polarimeter has no moving parts or modulated components so the complete Stokes vector can be measured from just one exposure - making it unique to astronomy. The time required for the determination of the full Stokes vector is limited only by detector efficiency and photon fluxes. The polarimeter utilizes a modified Fresnel rhomb that acts as a highly achromatic quarter wave plate and a beamsplitter (referred to as an RBS. We present a description of how the DOAP works, some of the optical design for the polarimeter. Calibration is an important and difficult issue with all polarimeters, but particularly in astronomical polarimeters. We give a description of calibration techniques appropriate to this type of polarimeter.
Stochastic nonhomogeneous incompressible Navier-Stokes equations
Cutland, Nigel J.; Enright, Brendan
We construct solutions for 2- and 3-D stochastic nonhomogeneous incompressible Navier-Stokes equations with general multiplicative noise. These equations model the velocity of a mixture of incompressible fluids of varying density, influenced by random external forces that involve feedback; that is, multiplicative noise. Weak solutions for the corresponding deterministic equations were first found by Kazhikhov [A.V. Kazhikhov, Solvability of the initial and boundary-value problem for the equations of motion of an inhomogeneous viscous incompressible fluid, Soviet Phys. Dokl. 19 (6) (1974) 331-332; English translation of the paper in: Dokl. Akad. Nauk SSSR 216 (6) (1974) 1240-1243]. A stochastic version with additive noise was solved by Yashima [H.F. Yashima, Equations de Navier-Stokes stochastiques non homogènes et applications, Thesis, Scuola Normale Superiore, Pisa, 1992]. The methods here extend the Loeb space techniques used to obtain the first general solutions of the stochastic Navier-Stokes equations with multiplicative noise in the homogeneous case [M. Capiński, N.J. Cutland, Stochastic Navier-Stokes equations, Applicandae Math. 25 (1991) 59-85]. The solutions display more regularity in the 2D case. The methods also give a simpler proof of the basic existence result of Kazhikhov.
Stokely Carmichael: The Story of Black Power.
Johnson, Jacqueline
This biography for younger readers presents the life of Stokely Carmichael, who made famous the phrase "Black Power" as he fought for the rights of black people in the United States and who later settled in Africa, where he organizes young Africans to work for their rights. The book is introduced by an overview of the civil rights…
Is Navier-Stokes turbulence chaotic?
Deissler, R. G.
1986-01-01
Whether turbulent solutions of the Navier-Stokes equations are chaotic is considered. Initially neighboring solutions for a low-Reynolds-number fully developed turbulence are compared. The turbulence is sustained by a nonrandom time-independent external force. The solutions separate exponentially with time, having a positive Liapunov characteristic exponent. Thus the turbulence is characterized as chaotic.
Stokes' theorem, volume growth and parabolicity
Valtorta, Daniele
2010-01-01
We present some new Stokes'type theorems on complete non-compact manifolds that extend, in different directions, previous work by Gaffney and Karp and also the so called Kelvin-Nevanlinna-Royden criterion for (p-)parabolicity. Applications to comparison and uniqueness results involving the p-Laplacian are deduced.
Stokes Equation in a Toy CD Hovercraft
de Izarra, Charles; de Izarra, Gregoire
2011-01-01
This paper deals with the study of a toy CD hovercraft used in the fluid mechanics course for undergraduate students to illustrate the lubrication theory described by the Stokes equation. An experimental characterization of the toy hovercraft (measurements of the air flow value, of the pressure in the balloon and of the thickness of the air film…
Stokes Equation in a Toy CD Hovercraft
de Izarra, Charles; de Izarra, Gregoire
2011-01-01
This paper deals with the study of a toy CD hovercraft used in the fluid mechanics course for undergraduate students to illustrate the lubrication theory described by the Stokes equation. An experimental characterization of the toy hovercraft (measurements of the air flow value, of the pressure in the balloon and of the thickness of the air film…
Full Stokes Spectropolarimetry of Hα in Prominences
López Ariste, A.; Casini, R.; Paletou, F.; Tomczyk, S.; Lites, B. W.; Semel, M.; Landi Degl'Innocenti, E.; Trujillo Bueno, J.; Balasubramaniam, K. S.
2005-03-01
We report on spectropolarimetric observations of Hα in prominences made with the Télescope Héliographique pour l'Etude du Magnétisme et des Instabilités Solaires and the High Altitude Observatory/Advanced Stokes Polarimeter. Stokes Q and U show the expected profile shape from resonance scattering polarization and the Hanle effect. In contrast, most of the time, Stokes V does not show the antisymmetric profile shape typical of the Zeeman effect but a profile that indicates the presence of strong atomic orientation in the hydrogen levels, to an extent that cannot be explained by invoking the alignment-to-orientation transfer mechanism induced by the prominence magnetic field. We found that the largest signal amplitudes of Stokes V (comparable to that of Stokes Q and U) could be produced by a process of selective absorption of circularly polarized radiation from the photosphere, which requires that the prominence be in the vicinity of an active region. Although recent observations of active region filaments indicate such a selective absorption mechanism as a plausible explanation of the anomalous signals observed, the particular set of conditions that must be met suggest that a different explanation may be required to explain the almost ubiquitous symmetric V signal observed in Hα prominences. Therefore, we speculate that an alternative mechanism inducing strong atomic orientation at the observed level could be due to the presence of electric fields inducing an electric Hanle effect on Hα. Although we are still working toward a careful modeling of this effect, including both electric and magnetic fields, we present some preliminary considerations that seem to support this possibility.
Observation of anomalous Stokes versus anti-Stokes ratio in MoTe2 atomic layers
Goldstein, Thomas; Chen, Shao-Yu; Xiao, Di; Ramasubramaniam, Ashwin; Yan, Jun
We grow hexagonal molybdenum ditelluride (MoTe2), a prototypical transition metal dichalcogenide (TMDC) semiconductor, with chemical vapor transport methods and investigate its atomic layers with Stokes and anti-Stokes Raman scattering. We report observation of all six types of zone center optical phonons. Quite remarkably, the anti-Stokes Raman intensity of the low energy layer-breathing mode becomes more intense than the Stokes peak under certain experimental conditions, creating an illusion of 'negative temperature'. This effect is tunable, and can be switched from anti-Stokes enhancement to suppression by varying the excitation wavelength. We interpret this observation to be a result of resonance effects arising from the C excitons in the vicinity of the Brillouin zone center, which are robust even for multiple layers of MoTe2. The intense anti-Stokes Raman scattering provides a cooling channel for the crystal and opens up opportunities for laser cooling of atomically thin TMDC semiconductor devices. Supported by the University of Massachusetts Amherst, the National Science Foundation Center for Hierarchical Manufacturing (CMMI-1025020) and Office of Emerging Frontiers in Research and Innovation (EFRI-1433496).
Stokes identification in an atomic ensemble using a filtering system
Institute of Scientific and Technical Information of China (English)
Luo Xiao-Ming; Ning Bo; Chen Li-Qing; Zhou Yue; Zhong Zhi-Ping; Jiang Shuo
2009-01-01
Polarization filtering and atomic cell filtering are applied in the identification of Stokes signals in an atomic ensemble, and reduce the noise to a level of 10~(-5) and 10~(-4) respectively. Good Stokes signals are then obtained. In this article the two filtering systems and the final Stokes output are presented, and the optimization of the polarization filtering system is highlighted.
Clustering algorithms for Stokes space modulation format recognition
DEFF Research Database (Denmark)
Boada, Ricard; Borkowski, Robert; Tafur Monroy, Idelfonso
2015-01-01
Stokes space modulation format recognition (Stokes MFR) is a blind method enabling digital coherent receivers to infer modulation format information directly from a received polarization-division-multiplexed signal. A crucial part of the Stokes MFR is a clustering algorithm, which largely...
Louis Pasteur, from crystals of life to vaccination.
Berche, P
2012-10-01
Louis Pasteur (1822-1895) is an exceptional scientist who opened a new era in medicine and biology. Starting from studies on crystals of by-products of wine fermentation, he first defined a distinct chemistry between dead and living matters. He then showed the role of living microbes in the fermentation and putrefaction processes. This brought him to challenge the two-millennium-old theory of spontaneous generation, using remarkably well-designed experiments. His observations on epidemics in silkworms allowed him to demonstrate the role of specific germs in infectious diseases. His discovery of the vaccine against fowl cholera can be considered as the birth of immunology. Finally, he became universally recognized through his famous vaccinations against anthrax and rabies.
[Louis Braille (1809-1852)--inventor of raised dots system].
Maciejewicz, Piotr; Kopacz, Dorota
2005-01-01
Louis Braille was born on January 4th 1809 in Coupvray, France. An injury to his eye at the age of three, resulted in total loss of vision. In 1819 he entered the Institute for Blind Youth in Paris. There he would live, study, and later teach. When he was fifteen, he developed system of reading and writing by means of raised dots, which is known today as Braille. The basis of the Braille system is known as a Braille cell. The cell is comprised of six dots numbered in a specific order. Each dot or combination of dots represents a letter of the alphabet. This Braille system has established itself internationally and formed the basic Braille for all languages.
Introduction to Louis Michel's lattice geometry through group action
Zhilinskii, Boris
2015-01-01
Group action analysis developed and applied mainly by Louis Michel to the study of N-dimensional periodic lattices is the central subject of the book. Different basic mathematical tools currently used for the description of lattice geometry are introduced and illustrated through applications to crystal structures in two- and three-dimensional space, to abstract multi-dimensional lattices and to lattices associated with integrable dynamical systems. Starting from general Delone sets the authors turn to different symmetry and topological classifications including explicit construction of orbifolds for two- and three-dimensional point and space groups. Voronoï and Delone cells together with positive quadratic forms and lattice description by root systems are introduced to demonstrate alternative approaches to lattice geometry study. Zonotopes and zonohedral families of 2-, 3-, 4-, 5-dimensional lattices are explicitly visualized using graph theory approach. Along with crystallographic applications, qualitative ...
Louis Vuitton与村上隆（Takashi Murakami）
Institute of Scientific and Technical Information of China (English)
婷婷
2009-01-01
高级时装与艺术的结合总是叫人欣喜兴奋，这样的跨界合作，不是炒红了艺术家就是抬高了品牌的知名度，这样相得益彰的事似乎已经不是设计师的心血来潮，而是成为了品牌每年固定“玩”的项目，甚至能够为一整季的服装配饰提供灵感。村上隆与Louis Vuictton的合作，简直成为了日后crossover合作的标本。高高在上的著名品牌LV皮包虽然一直以经典高贵著称，
Louis XVI et Marie-Antoinette. Un couple en politique
Wolikow, Claudine
2008-01-01
« Louis XVI. Toujours dire : cet infortuné monarque », avait noté Flaubert dans son Dictionnaire des idées reçues. Dans son ample biographie critique jumelée, Joël Félix s’en réclame comme d’une devise programmatique étayant son travail de décapage de l’image du couple formé par « le roi bienfaisant » et « la reine scélérate », formée tant par les protagonistes eux-mêmes que par leurs panégyristes ou détracteurs contemporains, sans oublier l’apport de « l’archéologie mystique » des nostalgiqu...
André-Louis Cholesky mathematician, topographer and army officer
Brezinski, Claude
2014-01-01
Outside the professional circles of topography and applied mathematics, the life and work of André-Louis Cholesky (1875–1918) are still relatively unknown to the scientific community. This new book appreciably widens the exposure of his remarkable personal achievements in topography and mathematics to a much larger international audience. Cholesky is also interesting to historians because he is a perfect representative of the "scientists engineers" that, since the early 19th century, had issued from the French scientific high schools. Because they had received a high level of mathematical education, they were able to innovate in their practice of engineering. In the case of Cholesky, this resulted in original contributions in artillery, topography, numerical analysis and graphical calculation. In addition, the book places his education and works within the history of several European countries through the 17th to 19th centuries. The book begins with Cholesky's biography, followed by his family’s hi...
Symmetries in nature the scientific heritage of Louis Michel
Todorov, Ivan; Zhilinskii, Boris
2014-01-01
Reflecting the oeuvre of “a man of two cultures: the culture of pure mathematics and the culture of theoretical physics” (in the words of his long time friend and co-author, Kameshwar Wali), this volume is centred around the notion of symmetry and its breaking. Starting with particle physics, the content proceeds to symmetries of matter, defects, and crystals. The mathematics of group extensions, non-linear group action, critical orbits and phase transitions is developed along the way. The symmetry principles and general mathematical tools provide unity in the treatment of different topics. The papers and lecture notes are preceded by a lively biography of Louis Michel and a commentary that relates his selected works both to the physics of his time and to contemporary trends. This book should be of interest to theoretical physicists, chemists, applied mathematicians and historians of science, and is accessible to graduate (and advanced undergraduate) students.
Louis H. Bauer and the origins of civil aviation medicine.
Kraus, Theresa L
2012-12-01
With the passage of the Air Commerce Act in May 1926, civil aviation safety became a federal responsibility under the Department of Commerce (DoC). In November of that year, Louis Hopewell Bauer (1888-1964) became the DoC's first Aviation Medical Director. After earning his medical degree at the Harvard School of Medicine in 1912, Bauer joined the U.S. Army Medical Corps, where he helped develop the role of the military flight surgeon and then served as director of the Army's School of Aviation Medicine. Upon taking the federal position, he undertook to define medical standards and examination frequencies for civilian pilots and identifiy disqualifying conditions that could compromise a pilot's ability to operate an aircraft safely. Bauer also personally selected 57 private physicians (soon to be known as Aviation Medical Examiners) distributed across the country to give medical examinations for pilot licenses. Bauer subsequently played a leading role in organizing the Aviation Medical Association in 1929.
Institute of Scientific and Technical Information of China (English)
凌嘉
2006-01-01
在Mr.Louis Vuitton这个称号下面,出身于知识分子家庭的Kanye West掀开的是一场艰巨而伟大的革命:改良与净化Hip-Hop,不让它继续以街头、毒品、暴力、攻击、色情、辱骂为音乐的主题,而是令其格调高雅、正义与健康起来。甚至连编曲也要革新,至少你不会在Kanye West的唱片里听到诸如女人呻吟、警车呼啸、街头群殴等等这些Hip-Hop里司空见惯的音乐采样。
Stokes-polarimetry imaging of tissue
Wu, Paul J.
A novel Stokes-polarimetry imaging system and technique was developed to quantify fully the polarization properties of light remitted from tissue. The uniqueness of the system and technique is established in the incident polarization. Here, the diffuse illumination is varied and controlled with the intention to improve the visibility of tissue structures. Since light retains some polarization even after multiple-scattering events, the polarization of remitted light depends upon the interactions within the material. Differentiation between tissue structures is accomplished by two-dimensional mapping of the imaged area using metrics such as the degree of linear polarization, degree of circular polarization, ellipticity, and Stokes parameters. While Stokes-polarimetry imaging can be applied to a variety of tissues and conditions, this thesis focuses on tissue types associated with the disease endometriosis. The current standard in diagnosing endometriosis is visual laparoscopy with tissue biopsy. The documented correlation between laparoscopy inspection and histological confirmation of suspected lesions was at best 67%. Endometrial lesions vary greatly in their appearance and depth of infiltration. Although laparoscopy permits tissue to be assessed by color and texture, to advance beyond the state-of-the-art, a new imaging modality involving polarized light was investigated; in particular, Stokes-polarimetry imaging was used to determine the polarization signature of light that interacted with tissue. Basic science studies were conducted on rat tails embedded within turbid gelatin. The purpose of these experiments was to determine how identification of sub-surface structures could be improved. Experimental results indicate image contrast among various structures such as tendon, soft tissue and intervertebral discs. Stokes-polarimetry imaging experiments were performed on various tissues associated with endometriosis to obtain a baseline characterization for each
Centro Federal de Comunidad Saint Louis - EE.UU.
Directory of Open Access Journals (Sweden)
Hellmuth, George
1980-04-01
Full Text Available The Community Federal Center lies in the outskirts of the town of Saint Louis. It was conceived and designed by the project authors — in a style characteristic of them — as a suburban architectonic complex for office use.
The work, standing out over an open stretch of land, has an ample base, with a volume that is neither the actual tower of the city centre nor the classic low rural construction.
The building's architectonic language permits an integration, by sympathy, in the context of the neighbouring uni-family housing zone, without naturally being assimilated in them, due to the disparity of functions. It is achieved through a fracture of scaled volumes, breaking the classic coldness of the big office building, whilst at the same time thanks to its robustness, it indicates the activity housed inside.
El Community Federal Center está emplazado en las afueras de la ciudad de Saint Louis. Fue concebido y diseñado por los autores del proyecto —en un estilo que les es característico—, como un complejo arquitectónico suburbano destinado a oficinas.
La obra, que se eleva sobre un terreno despejado, es amplía de base, presentando un volumen que no es ni la torre propia del centro urbano ni la clásica construcción rural de baja altura.
El lenguaje arquitectónico del edificio permite una integración, por simpatía, en el contexto de la zona de viviendas unifamiliares cercana, sin llegar, naturalmente, a asimilarse a ellas dada la disparidad de funciones. Se lleva a cabo por medio de una fractura de volúmenes, escalonados, que rompen la frialdad clásica del gran edificio de oficinas, sin dejar de indicar, por su robustez, la actividad que alberga en su interior.
Stokes analysis of an optical system
Georgiev, Georgi; Slavkovsky, Thomas
2009-03-01
As a transfer from research to teaching we are using stokes analysis to represent changes in the vectors for polarization of light as acted upon by the matrices of optical elements in undergraduate physics lab. The goal is to integrate students' knowledge for matrix analysis with an experimental determination of the changes in the polarization of light. This method allows students to learn how to design an optical system by using mathematical analysis, a skill necessary for future scientists or engineers in the fields of optics. We have tested and implemented the lab. The results are that it is well accepted by the students, but is very involved computationally, and needs to be shortened. The Stokes analysis needs to be introduces earlier in the curriculum in order to make the students comfortable with the formalism.
The classical version of Stokes' Theorem revisited
DEFF Research Database (Denmark)
Markvorsen, Steen
2008-01-01
Using only fairly simple and elementary considerations - essentially from first year undergraduate mathematics - we show how the classical Stokes' theorem for any given surface and vector field in $\\mathbb{R}^{3}$ follows from an application of Gauss' divergence theorem to a suitable modification...... of the vector field in a tubular shell around the given surface. The two stated classical theorems are (like the fundamental theorem of calculus) nothing but shadows of the general version of Stokes' theorem for differential forms on manifolds. The main points in the present paper, however, is firstly...... exercise, which simply relates the concepts of divergence and curl on the local differential level. The rest of the paper uses only integration in $1$, $2$, and $3$ variables together with a 'fattening' technique for surfaces and the inverse function theorem....
Complete Solutions to Extended Stokes' Problems
Directory of Open Access Journals (Sweden)
Chi-Min Liu
2008-01-01
Full Text Available The main object of the present study is to theoretically solve the viscous flow of either a finite or infinite depth, which is driven by moving plane(s. Such a viscous flow is usually named as Stokes' first or second problems, which indicates the fluid motion driven by the impulsive or oscillating motion of the boundary, respectively. Traditional Stokes' problems are firstly revisited, and three extended problems are subsequently examined. Using some mathematical techniques and integral transforms, complete solutions which can exactly capture the flow characteristics at any time are derived. The corresponding steady-state and transient solutions are readily determined on the basis of complete solutions. Current results have wide applications in academic researches and are of significance for future studies taking more boundary conditions and non-Newtonian fluids into account.
Infrared Stokes imaging polarimeter using microbolometers
Kudenov, Michael W.; Pezzaniti, J. Larry; Dereniak, Eustace L.; Gerhart, Grant R.
2009-08-01
A long wave infrared (LWIR) division of amplitude imaging Stokes polarimeter is presented. For the first time, to our knowledge, application of microbolometer focal plane array (FPA) technology to polarimetry is demonstrated. The sensor utilizes a wire-grid beamsplitter with imaging systems positioned at each output to analyze two orthogonal linear polarization states simultaneously. Combined with a form birefringent wave plate, the system is capable of snapshot imaging polarimetry in any one Stokes parameter (S1, S2 or S3). Radiometric and polarimetric calibration procedures for the instrument are provided and data from the instrument are presented, demonstrating the ability to measure intensity variations corresponding to polarized emission in natural environments. As such, emission polarimetry can be exploited at significantly reduced cost, sensor size and power consumption over instruments based on more costly Mercury-Cadmium Telluride (MCT) FPA's.
Stokes's cradle: Newton's cradle with liquid coating.
Donahue, C M; Hrenya, C M; Davis, R H
2010-07-16
Granular flows involving liquid-coated solids are ubiquitous in nature (pollen capture, avalanches) and industry (filtration, pharmaceutical mixing). In this Letter, three-body collisions between liquid-coated spheres are investigated experimentally using a "Stokes's cradle," which resembles the popular desktop toy Newton's cradle (NC). Surprisingly, previous work shows that every possible outcome was observed in the Stokes's cradle except the traditional NC outcome. Here, we experimentally achieve NC via guidance from a theory, which revealed that controlling the liquid-bridge volume connecting two target particles is the key in attaining the NC outcome. These three-body experiments also provide direct evidence that the fluid resistance upon rebound cannot be completely neglected due to presumed cavitation; this resistance also influences two-body systems yet cannot be isolated experimentally in such systems.
Three-Photon Stokes Mueller Polarimetry
Samim, Masood; Barzda, Virginijus
2015-01-01
The generalized theory of Stokes Mueller polarimetry is employed to develop the third-order optical polarimetry framework for third-harmonic generation (THG). The outgoing and incoming radiations are represented by 4-element and 16-element column vectors, respectively, and the intervening medium is represented by a $4\\times 16$ triple Mueller matrix. Expressions for the THG Stokes vector and the Mueller matrix are provided in terms of coherency and correlation matrices, and expanded by four-dimensional $\\gamma$ matrices that are analogues of Pauli matrices. Useful expressions of triple Mueller matrices are presented for cylindrically symmetric and isotropic structures. In addition, the relation between third-order susceptibilities and the measured triple Mueller matrix is provided. This theoretical framework can be applied for structural investigations of crystalline materials, including biological structures.
Effect of Stokes drift on upper ocean mixing
Institute of Scientific and Technical Information of China (English)
LI Shuang; SONG Jinbao; SUN Qun
2008-01-01
Stokes drift is the main source of vertical vorticity in the ocean mixed layer.In the ways of Coriolis - Stokes forcing and Langmuir circulations,Stokes drift can substantially affect the whole mixed layer.A modified Mellor-Yamada 2.5 level turbulence closure model is used to parameterize its effect on upper ocean mixing conventionally.Results show that comparing surface heating with wave breaking,Stokes drift plays the most important role in the entire ocean mixed layer,especially in the subsurface layer.As expected,Stokes drift elevates both the dissipation rate and the turbulence energy in the upper ocean mixing.Also,influence of the surface heating,wave breaking and wind speed on Stokes drift is investigated respectively.Research shows that it is significant and important to assessing the Stokes drift into ocean mixed layer studying.The laboratory observations are supporting numerical experiments quantitatively.
Data completion for the Stokes system
Ben Abda, Amel; Ben Saad, Imen; Hassine, Maatoug
2009-09-01
This Note is concerned with the severely ill-posed Cauchy-Stokes problem. This inverse problem is rephrased into an optimization one: An energy-like error functional is introduced. We prove that the optimality condition of the first order is equivalent to solving an interfacial equation which turns out to be a Cauchy-Steklov-Poincaré operator. Numerical trials highlight the efficiency of the present method. To cite this article: A. Ben Abda et al., C. R. Mecanique 337 (2009).
Vorticity, Stokes' Theorem and the Gauss's Theorem
Narayanan, M.
2004-12-01
Vorticity is a property of the flow of any fluid and moving fluids acquire properties that allow an engineer to describe that particular flow in greater detail. It is important to recognize that mere motion alone does not guarantee that the air or any fluid has vorticity. Vorticity is one of four important quantities that define the kinematic properties of any fluid flow. The Navier-Stokes equations are the foundation of fluid mechanics, and Stokes' theorem is used in nearly every branch of mechanics as well as electromagnetics. Stokes' Theorem also plays a vital role in many secondary theorems such as those pertaining to vorticity and circulation. However, the divergence theorem is a mathematical statement of the physical fact that, in the absence of the creation or destruction of matter, the density within a region of space can change only by having it flow into, or away from the region through its boundary. This is also known as Gauss's Theorem. It should also be noted that there are many useful extensions of Gauss's Theorem, including the extension to include surfaces of discontinuity in V. Mathematically expressed, Stokes' theorem can be expressed by considering a surface S having a bounding curve C. Here, V is any sufficiently smooth vector field defined on the surface and its bounding curve C. Integral (Surface) [(DEL X V)] . dS = Integral (Contour) [V . dx] In this paper, the author outlines and stresses the importance of studying and teaching these mathematical techniques while developing a course in Hydrology and Fluid Mechanics. References Arfken, G. "Gauss's Theorem." 1.11 in Mathematical Methods for Physicists, 3rd ed. Orlando, FL: Academic Press, pp. 57-61, 1985. Morse, P. M. and Feshbach, H. "Gauss's Theorem." In Methods of Theoretical Physics, Part I. New York: McGraw-Hill, pp. 37-38, 1953. Eric W. Weisstein. "Divergence Theorem." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/DivergenceTheorem.html
Exploring the Urban Heat Island (UHI) Effect in Port Louis, Mauritius
African Journals Online (AJOL)
2012r
2014-10-13
Oct 13, 2014 ... temperature due to artificial land cover and anthropogenic heat (Y. ... Exploring the Urban Heat Island (UHI) Effect in Port Louis, Mauritius. 140 ..... and intelligence in both design and technology in order to create sustainable.
Dr. Louis Sullivan: Treating America's Most Critical Health and Human Services Ills.
Cox, William E,; Matthews, Frank L.
1989-01-01
Interview with Dr. Louis Sullivan, Secretary of Health and Human Services. Discusses his views on health education, budget, access to health care, minority health, abortion, infant mortality, drugs, the Head Start Program, federal planning effects, and family influences. (JS)
Sources of Heavy Metal Pollution into the St. Louis River, Lake Superior Watershed
Sternberg, S. P.; Palokangas, C.
2013-12-01
The St. Louis River begins in Hoyt Lakes, Minnesota and enters Lake Superior between Duluth, Minnesota and Superior, Wisconsin. The Partridge River and the Embarrass River are two of its main tributaries. National Pollutant Discharge Elimination System (NPDES) permits are issued for surface water dischargers under the Clean Water Act. The Permit Compliance System (PCS) and the Integrated Compliance Information System (ICIS) is a tool allowing public access to information contained in NPDES permits. Along the way to Lake Superior, 19 facilities list the St. Louis River, St. Louis Bay, part of the St. Louis River estuary, or one of its tributaries as a receiving water. Of these 19 locations, four report discharging heavy metals into the receiving water. Copper and Lead are the metals most frequently discharged.
Genome Sequence of Enterovirus D68 from St. Louis, Missouri, USA, 2016
Wylie, Todd N.; Storch, Gregory A.
2017-01-01
ABSTRACT Enterovirus D68 (EV-D68) was rarely observed prior to a widespread outbreak in 2014. We observed its reemergence in St. Louis in 2016 and sequenced the EV-D68 genomes from two patient samples. The 2016 viruses in St. Louis differed from those we had sequenced from the 2014 outbreak but were similar to other viruses circulating nationally in 2016. PMID:28254971
Understanding Stokes forces in the wave-averaged equations
Suzuki, Nobuhiro; Fox-Kemper, Baylor
2016-05-01
The wave-averaged, or Craik-Leibovich, equations describe the dynamics of upper ocean flow interacting with nonbreaking, not steep, surface gravity waves. This paper formulates the wave effects in these equations in terms of three contributions to momentum: Stokes advection, Stokes Coriolis force, and Stokes shear force. Each contribution scales with a distinctive parameter. Moreover, these contributions affect the turbulence energetics differently from each other such that the classification of instabilities is possible accordingly. Stokes advection transfers energy between turbulence and Eulerian mean-flow kinetic energy, and its form also parallels the advection of tracers such as salinity, buoyancy, and potential vorticity. Stokes shear force transfers energy between turbulence and surface waves. The Stokes Coriolis force can also transfer energy between turbulence and waves, but this occurs only if the Stokes drift fluctuates. Furthermore, this formulation elucidates the unique nature of Stokes shear force and also allows direct comparison of Stokes shear force with buoyancy. As a result, the classic Langmuir instabilities of Craik and Leibovich, wave-balanced fronts and filaments, Stokes perturbations of symmetric and geostrophic instabilities, the wavy Ekman layer, and the wavy hydrostatic balance are framed in terms of intuitive physical balances.
El legado de Louis Pasteur The legacy of Lous Pasteur
Directory of Open Access Journals (Sweden)
Carlos Aguirre Muñoz
1996-01-01
Full Text Available
En este artículo se destacan cualidades de Louis Pasteur como la precocidad de su aptitud artística, la capacidad de concentración y reflexión y la perseverancia en sus empeños para lograr lo deseado; luego se hace una síntesis de su vida a través de sus logros científicos: sentar las bases de la estereoquímica, demostrar que las fermentaciones se deben a la acción de organismos vivos, probar que no existe la generación espontánea, aclarar la etiología de varias enfermedades humanas y animales y proponer soluciones para ellas, incluyendo la producción de vacunas, que culminó con el éxito de la vacunación antirrábica. Pasteur había nacido en una época en que predominaba la insalubridad y se corría grave riesgo de fallecer de enfermedades infectocontagiosas; a su muerte había contribuido inmensamente a mejorar esa situación.
Several qualities of Louis Pasteur are emphasized in this paper, namely: his artistic gift, his capacity for concentration and reflection and his perseverance in working to achieve his goals; a sinthesis of his life is presented through his scientific achievements: to establish the bases of stereochemistry, to prove that fermentations are due to the action of living organisms and that no spontaneous generation exists, to elucidate the etiology of several human and animal diseases and to propose solutions for them including the production of vaccines that culminated with the success of rabies vaccination. Pasteur had been born at a time of great unhealthiness and high risk of death due to infectious diseases; through his life-Iong research he considerably improved such situation.
Provenance and geographic spread of St. Louis encephalitis virus.
Kopp, Anne; Gillespie, Thomas R; Hobelsberger, Daniel; Estrada, Alejandro; Harper, James M; Miller, Richard A; Eckerle, Isabella; Müller, Marcel A; Podsiadlowski, Lars; Leendertz, Fabian H; Drosten, Christian; Junglen, Sandra
2013-06-11
St. Louis encephalitis virus (SLEV) is the prototypic mosquito-borne flavivirus in the Americas. Birds are its primary vertebrate hosts, but amplification in certain mammals has also been suggested. The place and time of SLEV emergence remain unknown. In an ecological investigation in a tropical rainforest in Palenque National Park, Mexico, we discovered an ancestral variant of SLEV in Culex nigripalpus mosquitoes. Those SLEV-Palenque strains form a highly distinct phylogenetic clade within the SLEV species. Cell culture studies of SLEV-Palenque versus epidemic SLEV (MSI-7) revealed no growth differences in insect cells but a clear inability of SLEV-Palenque to replicate in cells from birds, cotton rats, and free-tailed bats permissive for MSI-7 replication. Only cells from nonhuman primates and neotropical fruit bats were moderately permissive. Phylogeographic reconstruction identified the common ancestor of all epidemic SLEV strains to have existed in an area between southern Mexico and Panama ca. 330 years ago. Expansion of the epidemic lineage occurred in two waves, the first representing emergence near the area of origin and the second involving almost parallel appearances of the virus in the lower Mississippi and Amazon delta regions. Early diversification events overlapped human habitat invasion during the post-Columbian era. Several documented SLEV outbreaks, such as the 1964 Houston epidemic or the 1990 Tampa epidemic, were predated by the arrival of novel strains between 1 and 4 years before the outbreaks. Collectively, our data provide insight into the putative origins of SLEV, suggesting that virus emergence was driven by human invasion of primary rainforests. IMPORTANCE St. Louis encephalitis virus (SLEV) is the prototypic mosquito-transmitted flavivirus of the Americas. Unlike the West Nile virus, which we know was recently introduced into North America from the Old World, the provenience of SLEV is obscure. In an ecological investigation in a primary
Algumas reflexões sobre a autobiografia de Louis Althusser
Directory of Open Access Journals (Sweden)
Marta Rezende Cardoso
Full Text Available L’avenir dure longtemps (O futuro dura muito tempo, relato autobiográfico de Louis Althusser, é um texto de grande riqueza, e que se presta à investigação psicanalítica. Neste artigo, nossa leitura foi orientada por uma reflexão sobre o tema do superego. Explorando a história de Althusser, observamos um conflito interminável: ser subjugado, internamente, pela sexualidade inconsciente do outro. Analisamos o aspecto traumático e violento desta “relação de poder” – poder sexual – mostrando como esta se exerce na economia psíquica, aí delineando, a nível das instâncias psíquicas, uma configuração particular. Mediante este material, desenvolvemos a idéia de que a instância do superego é ancorada no pulsional, e que impõe no psiquismo um modo de “legalidade interna” implacável e contraditória na qual o indivíduo pode, de certa forma, permanecer prisioneiro.
CERN Bulletin
2010-01-01
François Louis, who was a CERN mathematician from 1957 to 1988, passed away on 23 March 2010. Everyone who was at CERN in the early years will remember the important role he played before the advent of computers, as well as his skills as a teacher when it became imperative for us all to make use of them. His lessons, at all levels, were remarkable for their precision and clarity. François loved to share his gifts of intelligence and culture with his friends and colleagues. Never turning down a request for help, he imparted his wisdom to the many who sought it with unfailing modesty and wit. We recall with affection his wonderful conversation, where mathematics merged with literature, cinema and his other great passion, music. Indeed he will also be remembered as a gifted pianist. His critical spirit and impeccable manners, born of a bygone era, left an indelible mark on us all. We are deeply saddened by his death. His friends
Experimental St. Louis encephalitis virus infection of sloths and cormorants.
Seymour, C; Kramer, L D; Peralta, P H
1983-07-01
Experimental infection of 11 Bradypus variegatus and Choloepus hoffmanni sloths with St. Louis encephalitis (SLE) virus produced detectable viremias of seven to 27 (median 13) days duration and maximum titers of 2.7 to 6.5 (median 5.1) log10 median suckling mouse intracranial lethal doses (SMicLD50) per ml. Experimental SLE viremia onset was delayed and maximum titer depressed in two sloths concurrently infected with naturally acquired viruses. SLE viremias in four experimentally inoculated cormorants Phalacrocorax olivaceus were shorter, and of equal or lower titer, than in sloths. Colonized Culex pipiens quinquefasciatus mosquitoes were infected by feeding on sloths circulating at least 4.8 log10 SMicLD50 of SLE virus per ml, and subsequently transmitted the infection to mice and chicks. An uninoculated baby Bradypus became infected by contact transmission from its mother. The antibody response of sloths to SLE virus was slow, being undetectable until several weeks post-inoculation. However, both sloth species developed high and long-lasting neutralizing and hemagglutination-inhibition antibody titers. The complement-fixation antibody response in Bradypus was lower and slower to develop than in Choloepus. Sloths with naturally acquired SLE virus antibody did not become detectably viremic after experimental inoculation. Neither sloths nor cormorants become overly ill from SLE virus infection.
On Kato's Method for Navier Stokes Equations
Haak, Bernhard H.; Kunstmann, Peer Chr.
2009-10-01
We investigate Kato’s method for parabolic equations with a quadratic non-linearity in an abstract form. We extract several properties known from linear systems theory which turn out to be the essential ingredients for the method. We give necessary and sufficient conditions for these conditions and provide new and more general proofs, based on real interpolation. In application to the Navier Stokes equations, our approach unifies several results known in the literature, partly with different proofs. Moreover, we establish new existence and uniqueness results for rough initial data on arbitrary domains in {mathbb{R}}3 and irregular domains in {mathbb{R}}n.
Some topics of Navier-Stokes solvers
Honma, H.; Nishikawa, N.
1990-03-01
The process of numerical simulation consists of selection of some items: a mathematical model, a numerical scheme, the level of the computer, and post processing. From this point of view, recent numerical studies of viscous flows are described especially for the fluid engineering laboratories in the Chiba University. The examples of simulations are Mach reflection on a wedge using a kinetic model equation and a cylinder-plate juncture flow using incompressible Navier Stokes equation. Some attempts at graphic monitoring of fluid mechanical calculations are also shown for some combinations of computers with Computational Fluid Dynamics (CFD) solvers.
Existence and properties of the Navier-Stokes equations
Zhirkin, Alexey V.
2016-01-01
A proof of existence, uniqueness and smoothness of the Navier-Stokes equations is an actual problem, which solution is important for different branches of science. The subject of this study is obtaining the smooth and unique solutions of the three-dimension Stokes-Navier equations for the initial and boundary value problem. The analysis shows that there exist no viscous solutions of the Navier-Stokes equations in three dimensions. The reason is the insufficient capability of the divergence-fr...
Adrian Stokes and the portrait of Melanie Klein.
Sayers, Janet
2015-08-01
This paper focuses on the offer by the art writer Adrian Stokes to commission and pay for a portrait of the psychoanalyst Melanie Klein by the artist William Coldstream. It details some of the precursors of this offer in Stokes's preceding involvement first with Klein and then with Coldstream; her response to this offer; and its outcome and aftermath in Stokes's subsequent writing about Klein and Coldstream. Copyright © 2015 Institute of Psychoanalysis.
Gravitational Stokes parameters. [for electromagnetic and gravitational radiation in relativity
Anile, A. M.; Breuer, R. A.
1974-01-01
The electromagnetic and gravitational Stokes parameters are defined in the general theory of relativity. The general-relativistic equation of radiative transfer for polarized radiation is then derived in terms of the Stokes parameters for both high-frequency electromagnetic and gravitational waves. The concept of Stokes parameters is generalized for the most general class of metric theories of gravity, where six (instead of two) independent states of polarization are present.
Historical revision of the differential Stokes-Mueller formalism: discussion.
Arteaga, Oriol
2017-03-01
The differential Stokes-Mueller matrix formalism expresses the local evolution of the Mueller matrix or the Stokes parameters for light propagating through a homogeneous optical medium. This paper presents a historical revision of the development of the differential Stokes-Mueller matrix formalism and highlights several important early contributions that have been overlooked. Particularly relevant is that this formalism was pioneered as early as 1929 by Paul Soleillet, almost 50 years earlier than it has been usually assumed. This historical revision demonstrates that several different authors independently formulated the differential Stokes-Mueller formalism during the 20th century and they found equivalent results studying the propagation problem from different approaches.
Stokes Space in Direct-Detection Data Transmission Systems
DEFF Research Database (Denmark)
Estaran Tolosa, Jose Manuel; Lu, Xiaofeng; Zibar, Darko;
2015-01-01
Stokes-based processing permits complete and phase-insensitive characterization of the field’s SOP, readily unlocking polarization diversity in transmission systems where DD is desired. We present an overview on Stokes notions and most recent achievements in this context.......Stokes-based processing permits complete and phase-insensitive characterization of the field’s SOP, readily unlocking polarization diversity in transmission systems where DD is desired. We present an overview on Stokes notions and most recent achievements in this context....
Christensen, Victoria G.; Lee, Kathy E.; Kieta, Kristen A.; Elliott, Sarah M.
2012-01-01
The St. Louis Bay of Lake Superior receives substantial urban runoff, wastewater treatment plant effluent, and industrial effluent. In 1987, the International Joint Commission designated the St. Louis Bay portion of the lower St. Louis River as one of the Great Lakes Areas of Concern. Concerns exist about the potential effects of chemicals of emerging concern on aquatic biota because many of these chemicals, including endocrine active chemicals, have been shown to affect the endocrine systems of fish. To determine the occurrence of chemicals of emerging concern in the St. Louis River, the St. Louis Bay, and Superior Bay, the U.S. Geological Survey in cooperation with the Minnesota Pollution Control Agency and the Wisconsin Department of Natural Resources collected water and bottom-sediment samples from 40 sites from August through October 2010. The objectives of this study were to (1) identify the extent to which chemicals of emerging concern, including pharmaceuticals, hormones, and other organic chemicals, occur in the St. Louis River, St. Louis Bay, and Superior Bay, and (2) identify the extent to which the chemicals may have accumulated in bottom sediment of the study area. Samples were analyzed for selected wastewater indicators, hormones, sterols, bisphenol A, and human-health pharmaceuticals. During this study, 33 of 89 chemicals of emerging concern were detected among all water samples collected and 56 of 104 chemicals of emerging concern were detected in bottom-sediment samples. The chemical N,N-diethyl-meta-toluamide (DEET) was the most commonly detected chemical in water samples and 2,6-dimethylnaphthalene was the most commonly detected chemical in bottom-sediment samples. In general, chemicals of emerging concern were detected at a higher frequency in bottom-sediment samples than in water samples. Estrone (a steroid hormone) and hexahydrohexamethyl cyclopentabensopyran (a synthetic fragrance) were the most commonly detected endocrine active chemicals in
Obituary: John Louis Africano III, 1951-2006
Barker, Edwin, S.
2007-12-01
The orbital debris, space surveillance, and astronomical communities lost a valued and beloved friend when John L. Africano passed away on July 27, 2006, at the young age of 55. John passed away in Honolulu, Hawaii, from complications following a heart attack suffered while playing racquetball, which was his avocation in life. Born on February 8, 1951, in Saint Louis, Missouri, John graduated with a B.S. in Physics from the University of Missouri at Saint Louis in 1973, and received a Master's degree in Astronomy from Vanderbilt University in 1974. John had a real love for astronomical observing and for conveying his many years of experience to others. He encouraged many young astronomers and mentored them in the basics of photometry and astronomical instrumentation. John was author or co-author on nearly one-hundred refereed publications ranging from analyses of cool stars to the timing of occultations to space surveillance. He was honored for his contributions to minor planet research when the Jet Propulsion Laboratory named Minor Planet 6391 (Africano) after him. John held operational staff positions at several major observatories including McDonald Observatory in Texas, Kitt Peak National Observatory in Arizona, and the Cloudcroft Telescope Facility in New Mexico. He observed at numerous observatories worldwide, including Cerro Tololo Inter-American Observatory (CTIO) in Chile, developing a world-wide network of friends and colleagues. John's ability to build diverse teams through his managerial and technical skills, not to mention his smiling personality, resulted in numerous successes in the observational astronomy and space surveillance arenas. As an astronomer for Boeing LTS Inc., he worked for many years at the Advanced Maui Optical and Space Surveillance site (AMOS) on Maui, Hawaii, where he contributed his operational and instrumental expertise to both the astronomy and space surveillance communities. He was also the co-organizer of the annual AMOS
Louis Pasteur, language, and molecular chirality. I. Background and dissymmetry.
Gal, Joseph
2011-01-01
Louis Pasteur resolved sodium ammonium (±)-tartrate in 1848, thereby discovering molecular chirality. Although hindered by the primitive state of organic chemistry, he introduced new terminology and nomenclature for his new science of molecular and crystal chirality. He was well prepared for this task by his rigorous education and innate abilities, and his linguistic achievements eventually earned him membership in the supreme institution for the French language, the Académie française. Dissymmetry had been in use in French from the early 1820s for disruption or absence of symmetry or for dissimilarity or difference in appearance between two objects, and Pasteur initially used it in the latter connotation, without any reference to handedness or enantiomorphism. Soon, however, he adopted it in the meaning of chirality. Asymmetry had been in use in French since 1691 but Pasteur ignored it in favor of dissymmetry. The two terms are not synonymous but it is not clear whether Pasteur recognized this difference in choosing the former over the latter. However, much of the literature mistranslates his dissymmetry as asymmetry. Twenty years before Pasteur the British polymath John Herschel proposed that optical rotation in the noncrystalline state is due to the "unsymmetrical" [his term] nature of the molecules and later used dissymmetrical for handed. Chirality, coined by Lord Kelvin in 1894 and introduced into chemistry by Mislow in 1962, has nearly completely replaced dissymmetry in the meaning of handedness, but the use of dissymmetry continues today in other contexts for lack of symmetry, reduction of symmetry, or dissimilarity.
Skewed Riskscapes and Environmental Injustice: A Case Study of Metropolitan St. Louis
Abel, Troy D.
2008-08-01
This article presents a case study of Toxics Release Inventory (TRI) air pollution exposure risks across metropolitan St. Louis. The first section critically reviews environmental justice research and related barriers to environmental risk management. Second, the paper offers a conventional analysis of the spatial patterns of TRI facilities and their surrounding census block group demographics for metropolitan St. Louis. Third, the article describes the use of an exposure risk characterization for 319 manufacturers and their air releases of more than 126 toxic pollutants. This information could lead to more practical resolutions of urban environmental injustices. The analysis of TRIs across metropolitan St. Louis shows that minority and low-income residents were disproportionately closer to industrial pollution sources at nonrandom significance levels. Spatial concentrations of minority residents averaged nearly 40% within one kilometer of St. Louis TRI sites compared to 25% elsewhere. However, one-fifth of the region’s air pollution exposure risk over a decade was spatially concentrated among only six facilities on the southwestern border of East St. Louis. This disproportionate concentration of some of the greatest pollution risk would never be considered in most conventional environmental justice analyses. Not all pollution exposure risk is average, and the worst risks deserve more attention from environmental managers assessing and mitigating environmental injustices.
Possibility of turbulence from a post-Navier-Stokes equation
Energy Technology Data Exchange (ETDEWEB)
Getreuer, Pascal [Mathematics Department, University of California, Los Angeles, Los Angeles, CA 90095 (United States); Albano, A.M. [Department of Physics, Bryn Mawr College, Bryn Mawr, PA 19010 (United States)]. E-mail: aalbano@brynmawr.edu; Muriel, A. [Data Transport Systems, 347 East 62nd street, New York, NY 10021 (United States)
2007-06-18
We introduce corrections to the Navier-Stokes equation arising from the transitions between molecular states and the injection of external energy. In the simplest application of the proposed post-Navier-Stokes equation, we find a multi-valued velocity field and the immediate possibility of velocity reversal, both features of turbulence.
Possibility of Turbulence from a Post-Navier-Stokes Equation
Getreuer, P; Muriel, A; Getreuer, Pascal
2006-01-01
We introduce corrections to the Navier-Stokes equation arising from the transitions between molecular states and the injection of external energy. In the simplest application of the proposed post Navier-Stokes equation, we find a multi-valued velocity field and the immediate possibility of velocity reversal, both features of turbulence.
COMPARISON OF STABILITY BETWEEN NAVIER-STOKES AND EULER EQUATIONS
Institute of Scientific and Technical Information of China (English)
SHI Wei-hui; WANG Yue-peng; SHEN Chun
2006-01-01
The stability about Navier-Stokes equation and Euler equation was brought into comparison. And by taking their typical initial value problem for example, the reason of leading to the difference in stability between Navier-Stokes equation and Euler equation was also analyzed.
A note on the Stokes operator and its powers
Guermond, Jean-Luc
2010-04-28
The so-called Stokes operator is an important tool in the analysis of the solutions of the Navier-Stokes equations and their numerical approximation. The aim of this note is to clarify certain properties of the fractional powers of this operator which are sometimes misused. © 2010 Korean Society for Computational and Applied Mathematics.
Tip loss correction for actuator / Navier Stokes computations
DEFF Research Database (Denmark)
Shen, Wen Zhong; Sørensen, Jens Nørkær; Mikkelsen, Robert Flemming
2004-01-01
The new tip loss correction, initially developed for ID BEM computations [1], is now extended to 2D Actuator Disc / Navier-Stokes (AD/NS) computations and 3D Actuator Line / Navier-Stokes (AL/NS) computations. As shown in the paper, the tip loss correction is an important and necessary step...
Stokes Polarimetry at the Kodaikanal Tower Tunnel Telescope
Indian Academy of Sciences (India)
Κ. Sankarasubramanian; G. Srinivasulu; A. V. Ananth; P. Venkatakrishnan
2000-09-01
A Stokes Polarimeter has been developed using a masked CCD arrangement for the measurement of the vector magnetic field of sunspots. Charge shifting within the CCD is used to record near simultaneous orthogonal polarisation. The testing of the Stokes Polarimeter and the behavior of the integrated system combined with the Kodaikanal tower tunnel telescope will be discussed.
High Stokes shift perylene dyes for luminescent solar concentrators.
Sanguineti, Alessandro; Sassi, Mauro; Turrisi, Riccardo; Ruffo, Riccardo; Vaccaro, Gianfranco; Meinardi, Francesco; Beverina, Luca
2013-02-25
Highly efficient plastic based single layer Luminescent Solar Concentrators (LSCs) require the design of luminophores having complete spectral separation between absorption and emission spectra (large Stokes shift). We describe the design, synthesis and characterization of a new perylene dye possessing Stokes shift as high as 300 meV, fluorescent quantum yield in the LSC slab of 70% and high chemical and photochemical stability.
Two-Scale Convergence of Unsteady Stokes Type Equations
Signing, Lazarus
2011-01-01
In this paper we study the homogenization of unsteady Stokes type equations in the periodic setting. The usual Laplace operator involved in the classical Stokes equations is here replaced by a linear elliptic differential operator of divergence form with periodically oscillating coefficients. Our mean tool is the well known two-scale convergence method.
Equivalence of dynamical ensembles and Navier-Stokes equations
Gallavotti, G
1996-01-01
A reversible version of the Navier Stokes equation is studied. A conjecture emerges stating the equivalence between the reversible equation and the usual Navier Stokes equation. The latter appears as a statement of ensembles equivalence in the limit of infinite Reynolds number, which plays the role of the thermodynamic limit.
The Absence of Stokes Drift in Waves
Chafin, Clifford
2015-01-01
Stokes drift has been as central to the history of wave theory as it has been distressingly absent from experiment. Neither wave tanks nor experiments in open bodies detect this without nearly canceling "eulerian flows." Acoustic waves have an analogous problem that is particularly problematic in the vorticity production at the edges of beams. Here we demonstrate that the explanation for this arises from subtle end-of-packet and wavetrain gradient effects such as microbreaking events and wave-flow decomposition subtleties required to conserve mass and momentum and avoid fictitious external forces. These losses occur at both ends of packets and can produce a significant nonviscous energy loss for translating and spreading surface wave packets and wavetrains. In contrast, monochromatic sound wave packets will be shown to asymmetrically distort to conserve momentum. This provides an interesting analogy to how such internal forces arise for gradients of electromagnetic wavetrains in media. Such examples show that...
The other optimal Stokes drag profile
Montenegro-Johnson, Thomas D
2014-01-01
The lowest drag shape of fixed volume in Stokes flow has been known for some 40 years. It is front-back symmetric and similar to an American football with ends tangent to a cone of 60 degrees. The analogous convex axisymmetric shape of fixed surface area, which may be of interest for particle design in chemistry and colloidal science, is characterized in this paper. This "other" optimal shape has a surface vorticity proportional to the mean surface curvature, which is used with a local analysis of the flow near the tip to show that the front and rear ends are tangent to a cone of angle 30.8 degrees. Using the boundary element method, we numerically represent the shape by expanding its tangent angle in terms decaying odd Legendre modes, and show that it has 11.3% lower drag than a sphere of equal surface area, significantly more pronounced than for the fixed-volume optimal.
Generalized extended Navier-Stokes theory
DEFF Research Database (Denmark)
Hansen, J. S.; Daivis, Peter J.; Dyre, Jeppe C.
2013-01-01
in molecular fluids. To discuss these phenomena in detail, molecular dynamics simulations of molecular chlorine are performed for three different state points. In general, the theory captures the behavior for small wavevector and frequencies as expected. For example, in the hydrodynamic regime......The extended Navier-Stokes theory accounts for the coupling between the translational and rotational molecular degrees of freedom. In this paper, we generalize this theory to non-zero frequencies and wavevectors, which enables a new study of spatio-temporal correlation phenomena present...... and for molecular fluids with small moment of inertia like chlorine, the theory predicts that the longitudinal and transverse intrinsic angular velocity correlation functions are almost identical, which is also seen in the molecular dynamics simulations. However, the theory fails at large wavevector and frequencies...
Stokes shift spectroscopy for breast cancer diagnosis
Jeyasingh, Ebenezar; Prakashrao, Aruna; Singaravelu, Ganesan
2010-02-01
The objective of this study is to assess the diagnostic potential of stokes shift (SS) spectroscopy (SSS) for normal and different pathological breast tissues such as fibroadenoma and infiltrating ductal carcinoma. The SS spectra is measured by simultaneously scanning both the excitation and emission wavelengths while keeping a fixed wavelength interval Δλ=20 nm between them. Characteristic, highly resolved peaks and significant spectral differences between normal and different pathological breast tissues were observed. The SS spectra of normal and different pathological breast tissues shows the distinct peaks around 300, 350, 450, 500 and 600 nm may be attributed to tryptophan, collagen, NADH, flavin and porphyrin respectively. Using SSS technique one can obtain all the key fluorophores in a single scan and hence they can be targeted as a tumor markers in this study. In order to quantify the altered spectral differences between normal and different pathological breast tissues are verified by different ratio parameters.
2-Cam LWIR imaging Stokes polarimeter
Kudenov, Michael W.; Dereniak, Eustace L.; Pezzaniti, Larry; Gerhart, Grant R.
2008-04-01
A 2-Cam micro-bolometer imaging polarimeter operating in the LWIR is presented. The system is capable of snapshot imaging Stokes polarimetry in any one channel (S I, S II, or S 3) by taking two simultaneous measurements of a scene. For measurements of S I or S II, the instrument relies on a specially optimized wire-grid beam-splitter. For measurements of S 3, a form birefringent quarter-wave retarder is inserted into the optical path. Specifics associated with the design of the wire-grid beam-splitter and the form birefringent quarter-wave retarder will be overviewed, with inclusion of RCWA simulations. Calibration and simulation procedures, as well as calibration targets, will be highlighted, and initial data from the instrument are presented.
Frictionless dispersive hydrodynamics of Stokes flows
Maiden, Michelle D; Anderson, Dalton V; Schubert, Marika E; Hoefer, Mark A
2016-01-01
Effectively frictionless, dispersive flow characterizes superfluids, nonlinear optical diffraction, and geophysical fluid interfaces. Dispersive shock waves (DSWs) and solitons are fundamental nonlinear excitations in these media, but DSW studies to date have been severely constrained by a loss of coherence. Here we report on a novel dispersive hydrodynamics testbed: the effectively frictionless flow of interfacial waves between two high contrast, low Reynolds' number Stokes fluids. This system enables high fidelity observations of large amplitude DSWs, found to agree quantitatively with a nonlinear wave averaging theory. We then report on observations of highly coherent phenomena including DSW backflow, the refraction or absorption of solitons by DSWs, and multi-phase DSW-DSW merger. The complex, coherent, nonlinear mixing of DSWs and solitons observed here are universal features of dissipationless, dispersive hydrodynamic flows.
[Louis Ombrédanne (1871-1956) pediatric and plastic surgeon].
Glicenstein, J
2015-04-01
One of the fathers of pediatric surgery in France, Louis Ombrédanne (1871-1956) was a great plastic surgeon. During his residency he was initiated to plastic surgery by Charles Nélaton (1851-1911). Both wrote two books: "La rhinoplastie" and "Les autoplasties", taking stock of these techniques in the early 20th century. In 1906, he was the first to describe the pectoral muscle flap for immediate breast reconstruction after mastectomy. He used this flap in conjunction with an axillo thoracic flap. From 1908 to 1941, Louis Ombrédanne practised pediatric surgery, most of which was devoted in reconstruction of congenital and acquire anomalies. From 1924 to 1941, he was Professor of pediatric surgery at the hospital Enfants-Malades in Paris. In 1907, Louis Ombrédanne created a prototype of an ether inhaler as a safe anesthetic device. The device was successfully used for fifty years in Europe.
Saint-Louis, Senegal: from heritage to tourism. Compromised local development?
Directory of Open Access Journals (Sweden)
Abdoul Sow
2017-05-01
Full Text Available Former trading post, colonial city, and French imperial capital turned provincial city in the wake of Africa’s independence movements, Saint-Louis in Senegal stands out among the cities of Sub-Saharan Africa. Inscribed on UNESCO’s World Heritage List in December of 2000, the city should be a cultural reference point on the nation’s tourist circuit. Over fifteen years after its inscription, the greater “Saintlouisian” (from Saint-Louis area is, however, faced with numerous difficulties and its tourism sector has been unable to lift the city out of its economic stagnation. This article analyzes Saint-Louis and the region in which is located as a tourist destination in the context of the Sahelian crisis by focusing on the heritage/tourism binary and its socioeconomic, spatial, and political consequences.
Leslie, Thomas
2006-01-01
Artikkel põhineb Thomas Leslie Kuressaares Louis Kahni päevadel peetud ettekandel. Louis Kahni koostöös August Komendandiga projekteeritud hoonetest pikemalt Richardsi Meditsiiniliste Uuringute laboratooriumist, Salki bioloogianistituudist (1959-1965, La Jolla, Kalifornia) ja Kimbelli kunstimuuseumist (1966-1972, Texas, Fort Worth). Bibl. lk. 75
Suiter, Mary C.; Stierholz, Katrina L.
2011-01-01
Data and primary source documents are important for understanding past and current events. The Federal Reserve Bank of St. Louis has committed itself to the collection and illumination of economic data and historical information for classroom teachers and researchers. The Federal Reserve Bank of St. Louis provides a number of services--including…
Grooms, Ain A.
2016-01-01
A dual transfer program was created in 1983 in the St. Louis metropolitan area following a 1972 lawsuit brought upon the city, charging it with withholding an equal educational opportunity for Black students. Through this program, Black students from St. Louis City are provided with free transportation to one of 15 suburban school districts, and…
Leslie, Thomas
2006-01-01
Artikkel põhineb Thomas Leslie Kuressaares Louis Kahni päevadel peetud ettekandel. Louis Kahni koostöös August Komendandiga projekteeritud hoonetest pikemalt Richardsi Meditsiiniliste Uuringute laboratooriumist, Salki bioloogianistituudist (1959-1965, La Jolla, Kalifornia) ja Kimbelli kunstimuuseumist (1966-1972, Texas, Fort Worth). Bibl. lk. 75
Tyng, Anne Griswold
2007-01-01
Louis Kahni betoonarhitektuurist (Weissi maja, 1947-1949), Yale'i kunstigaleriist (1951-1953), City Toweri projektist (1952-1958), Trentoni supelmajast (1954-1956), Salki instituudist (1959-1965, La Jolla, California), Kimbelli kunstimuuseumist (1968-1974), pealinnakompleksist Dhakas (1965-1974). Anne Griswold Tyng hakkas L. Kahni juures tööle 1945. a., tema algkooli projektist (1949-50), oma Philadelphia maja juurdeehitusest (1965-1968)
Tyng, Anne Griswold
2007-01-01
Louis Kahni betoonarhitektuurist (Weissi maja, 1947-1949), Yale'i kunstigaleriist (1951-1953), City Toweri projektist (1952-1958), Trentoni supelmajast (1954-1956), Salki instituudist (1959-1965, La Jolla, California), Kimbelli kunstimuuseumist (1968-1974), pealinnakompleksist Dhakas (1965-1974). Anne Griswold Tyng hakkas L. Kahni juures tööle 1945. a., tema algkooli projektist (1949-50), oma Philadelphia maja juurdeehitusest (1965-1968)
Approximate Stokes Drift Profiles and their use in Ocean Modelling
Breivik, Oyvind; Bidlot, Jea-Raymond; Janssen, Peter A. E. M.; Mogensen, Kristian
2016-04-01
Deep-water approximations to the Stokes drift velocity profile are explored as alternatives to the monochromatic profile. The alternative profiles investigated rely on the same two quantities required for the monochromatic profile, viz the Stokes transport and the surface Stokes drift velocity. Comparisons against parametric spectra and profiles under wave spectra from the ERA-Interim reanalysis and buoy observations reveal much better agreement than the monochromatic profile even for complex sea states. That the profiles give a closer match and a more correct shear has implications for ocean circulation models since the Coriolis-Stokes force depends on the magnitude and direction of the Stokes drift profile and Langmuir turbulence parameterizations depend sensitively on the shear of the profile. Of the two Stokes drift profiles explored here, the profile based on the Phillips spectrum is by far the best. In particular, the shear near the surface is almost identical to that influenced by the f-5 tail of spectral wave models. The NEMO general circulation ocean model was recently extended to incorporate the Stokes-Coriolis force along with two other wave-related effects. The ECWMF coupled atmosphere-wave-ocean ensemble forecast system now includes these wave effects in the ocean model component (NEMO).
STOKES FLOW DUE TO FUNDAMENTAL SINGULARITIES BEFORE A PLANE BOUNDARY
Institute of Scientific and Technical Information of China (English)
N.Aktar; F. Rahman; S.K. Sen
2004-01-01
A representation for the velocity and pressure fields in three-dimensional Stokes flow was presented in terms of a biharmonic function A and a harmonic function B. This representation was used to establish a general theorem for the calculation of Stokes flow due to fundamental singularities in a region bounded by a stationary no-slip plane boundary.Collins' s theorem for axisymmetric Stokes flow before a rigid plane follows as a special case of the theorem. A few illustrative examples are given to show its usefulness.
3D Topology optimization of Stokes flow problems
DEFF Research Database (Denmark)
Gersborg-Hansen, Allan; Dammann, Bernd
of energy efficient devices for 2D Stokes flow. Creeping flow problems are described by the Stokes equations which model very viscous fluids at macro scales or ordinary fluids at very small scales. The latter gives the motivation for topology optimization problems based on the Stokes equations being a model...... the designs are 3D. Moreover, preliminary results show that a formulation of an optimization problem that maximizes mixing with a constraint on the pressure drop across the device gives promising results. To measure the mixing a step temperature profile is convected through the design and the resulting...
Stokes vector formalism based second harmonic generation microscopy
Qiu, Jianjun; Mazumder, Nirmal; Tsai, Han-Ruei; Hu, Chih-Wei; Kao, Fu-Jen
2012-02-01
In this study, we have developed a four-channel Stokes vector formalism based second harmonic generation (SHG) microscopy to map and analyze SHG signal. A four-channel Stokesmeter setup is calibrated and integrated into a laser scanning microscope to measure and characterize the SH's corresponding Stokes parameters. We are demonstrating the use of SH and its Stokes parameters to visualize the birefringence and crystalline orientation of KDP and collagen. We believe the developed method can reveal unprecedented information for biomedical and biomaterial studies.
Preconditioning the pressure operator for the time dependent Stokes problem
Energy Technology Data Exchange (ETDEWEB)
Bramble, J.H.; Pasciak, J.E.
1994-12-31
In implicit time stepping procedures for the linearized Navier Stokes equations, a linear perturbed Stokes problem must be solved at each time step. Many methods for doing this require a good preconditioner for the resulting pressure operator (Schur complement). In contrast to the time independent Stokes equations where the pressure operator is well conditioned, the pressure operator for the perturbed system becomes more illconditioned as the time step is reduced (and/or the Reynolds number is increased). The authors describe the method for solving the coupled velocity/pressure systems and, in particular, show how to construct good preconditioners for the poorly conditioned pressure operator.
Stokes polarimetry imaging of dog prostate tissue
Kim, Jihoon; Johnston, William K., III; Walsh, Joseph T., Jr.
2010-02-01
Prostate cancer is the second leading cause of death in the United States in 2009. Radical prostatectomy (complete removal of the prostate) is the most common treatment for prostate cancer, however, differentiating prostate tissue from adjacent bladder, nerves, and muscle is difficult. Improved visualization could improve oncologic outcomes and decrease damage to adjacent nerves and muscle important for preservation of potency and continence. A novel Stokes polarimetry imaging (SPI) system was developed and evaluated using a dog prostate specimen in order to examine the feasibility of the system to differentiate prostate from bladder. The degree of linear polarization (DOLP) image maps from linearly polarized light illumination at different visible wavelengths (475, 510, and 650 nm) were constructed. The SPI system used the polarization property of the prostate tissue. The DOLP images allowed advanced differentiation by distinguishing glandular tissue of prostate from the muscular-stromal tissue in the bladder. The DOLP image at 650 nm effectively differentiated prostate and bladder by strong DOLP in bladder. SPI system has the potential to improve surgical outcomes in open or robotic-assisted laparoscopic removal of the prostate. Further in vivo testing is warranted.
Obtaining Stokes Parameters from the SUMI Experiment
Fayock, Brian; Winebarger, Amy; Cirtain, Jonathan; Kobayashi, Ken; West, Ed
2014-01-01
A sounding rocket experiment designed at the Marshall Space Flight Center, named the Solar Ultraviolet Magnetograph Investigation, had its second launch in July of 2012 to test the feasibility of measuring polarization signals of the ionized magnesium resonance doublet near 280 nm, originating from the transition region. The rocket housed a telescope at the front end and an imaging system at the rear end. Placed at the focal point of the self-filtering telescope, a wave plate rotated through 12 predefined angular orientations to restrict the measurements to specific combinations of circular and linear polarization. Coupled with a double Wollaston analyzer, the linearly polarized ordinary and extraordinary beams were measured for the 12 combinations, each containing different fractions of the Stokes parameters (I, Q, U, V). A thorough analysis of the data has allowed us to come to several conclusions regarding the design of the experiment. 1) We are confident that polarization can be measured. A sunspot region was determined to exhibit similar results over multiple pixels. 2) Measurements are limited by resolution, i.e. regions smaller than the angular resolution per pixel cannot be resolved with any certainty. 3) Temporal evolution of magnetic features must be considered in future experimental designs. Measurements need to be taken in repeated cycles as opposed to a single cycle over the duration of the experiment. In our presentation, we will provide a summary of the observations along with the methods of our analysis, including the limitations that we've encountered.
Multispectral Stokes polarimetry for dermatoscopic imaging
Castillejos, Y.; Martínez-Ponce, Geminiano; Mora-Nuñez, Azael; Castro-Sanchez, R.
2015-12-01
Most of skin pathologies, including melanoma and basal/squamous cell carcinoma, are related to alterations in external and internal order. Usually, physicians rely on their empirical expertise to diagnose these ills normally assisted with dermatoscopes. When there exists skin cancer suspicion, a cytology or biopsy is made, but both laboratory tests imply an invasive procedure. In this regard, a number of non-invasive optical techniques have been proposed recently to improve the diagnostic certainty and assist in the early detection of cutaneous cancer. Herein, skin optical properties are derived with a multispectral polarimetric dermatoscope using three different illumination wavelength intervals centered at 470, 530 and 635nm. The optical device consist of two polarizing elements, a quarter-wave plate and a linear polarizer, rotating at a different angular velocity and a CCD array as the photoreceiver. The modulated signal provided by a single pixel in the acquired image sequence is analyzed with the aim of computing the Stokes parameters. Changes in polarization state of selected wavelengths provide information about the presence of skin pigments such as melanin and hemoglobin species as well as collagen structure, among other components. These skin attributes determine the local physiology or pathology. From the results, it is concluded that optical polarimetry will provide additional elements to dermatologists in their diagnostic task.
Chaos Synchronization in Navier-Stokes Turbulence
Lalescu, Cristian; Meneveau, Charles; Eyink, Gregory
2013-03-01
Chaos synchronization (CS) has been studied for some time now (Pecora & Carroll 1990), for systems with only a few degrees of freedom as well as for systems described by partial differential equations (Boccaletti et al 2002). CS in general is said to be present in coupled dynamical systems when a specific property of each system has the same time evolution for all, even though the evolution itself is chaotic. The Navier-Stokes (NS) equations describe the velocity for a wide range of fluids, and their solutions are usually called turbulent if fluctuation amplitudes decrease as a power of their wavenumber. There have been some studies of CS for continuous systems (Kocarev et al 1997), but CS for NS turbulence seems not to have been investigated so far. We focus on the synchronization of the small scales of a turbulent flow for which the time history of large scales is prescribed. Our DNS results show that high-wavenumbers in turbulence are fully slaved to modes with wavenumbers up to a critical fraction of the Kolmogorov dissipation wavenumber. The motivation for our work is to study deeply sub-Kolmogorov scales in fully developed turbulence (Schumacher 2007), which we found to be recoverable even at very high Reynolds number from simulations with moderate resolutions. This work is supported by the National Science Foundation's CDI-II program, project CMMI-0941530
Scaling Navier-Stokes Equation in Nanotubes
Garajeu, Mihail; Saccomandi, Giuseppe
2013-01-01
On one hand, classical Monte Carlo and molecular dynamics (MD) simulations have been very useful in the study of liquids in nanotubes, enabling a wide variety of properties to be calculated in intuitive agreement with experiments. On the other hand, recent studies indicate that the theory of continuum breaks down only at the nanometer level; consequently flows through nanotubes still can be investigated with Navier-Stokes equations if we take suitable boundary conditions into account. The aim of this paper is to study the statics and dynamics of liquids in nanotubes by using methods of non-linear continuum mechanics. We assume that the nanotube is filled with only a liquid phase; by using a second gradient theory the static profile of the liquid density in the tube is analytically obtained and compared with the profile issued from molecular dynamics simulation. Inside the tube there are two domains: a thin layer near the solid wall where the liquid density is non-uniform and a central core where the liquid de...
Scaling properties of Navier-Stokes turbulence
Institute of Scientific and Technical Information of China (English)
Zhao-cun LIU
2009-01-01
The property of the velocity field and the cascade process of the fluid flow are key problems in turbulence research. This study presents the scaling property of the turbulent velocity field and a mathematical description of the cascade process, using the following methods: (1) a discussion of the general self-similarity and scaling invariance of fluid flow from the viewpoint of the physical mechanism of turbulent flow; (2) the development of the relationship between the scaling indices and the key parameters of the She and Leveque (SL) model in the inertial range; (3) an investigation of the basis of the fractal model and the multi-fractal model of turbulence; (4) a demonstration of the physical meaning of the flowing field scaling that is related to the real flowing vortex. The results illustrate that the SL model could be regarded as an approximate mathematical solution of Navier-Stokes (N-S) equations, and that the phenomena of normal scaling and anomalous scaling is the result of the mutual interactions among the physical factors of nonlinearity, dissipation, and dispersion. Finally, a simple turbulent movement conceptional description model is developed to show the local properties and the instantaneous properties of turbulence.
Optimal propulsive flapping in Stokes flows
Was, Loic
2014-01-01
Swimming fish and flying insects use the flapping of fins and wings to generate thrust. In contrast, microscopic organisms typically deform their appendages in a wavelike fashion. Since a flapping motion with two degrees of freedom is able, in theory, to produce net forces from a time-periodic actuation at all Reynolds number, we compute in this paper the optimal flapping kinematics of a rigid spheroid in a Stokes flow. The hydrodynamics for the force generation and energetics of the flapping motion is solved exactly. We then compute analytically the gradient of a flapping efficiency in the space of all flapping gaits and employ it to derive numerically the optimal flapping kinematics as a function of the shape of the flapper and the amplitude of the motion. The kinematics of optimal flapping are observed to depend weakly on the flapper shape and are very similar to the figure-eight motion observed in the motion of insect wings. Our results suggest that flapping could be a exploited experimentally as a propul...
Biology, History and Louis Pasteur: A New Approach to Teaching Science.
Hendrick, Robert
1991-01-01
Presents a rationale for using the history of science in science education. Uses the life and work of Louis Pasteur to illustrate how the history of science can illustrate the nature of science. Describes how Pasteur's bourgeois ideology and ambition influenced his selection of problems to investigate. (over 35 references) (PR)
The faucet snail (Bithynia tentaculata) invades the St. Louis River Estuary
The European-origin faucet snail (Bithynia tentaculata) now numbers among the aquatic invasive species present in the St. Louis River Estuary. This snail has been in the lower Great Lakes since the early 20th century but is new to the Lake Superior basin. We found faucet snails...
Sulfuric acid-ammonium sulfate aerosol: optical detection in the St. Louis region.
Charlson, R J; Vanderpol, A H; Covert, D S; Waggnoner, A P; Ahlquist, N C
1974-04-12
Nephelometric sensing of the deliquescence of ammonium sulfate produced by the reaction of sulfuric acid or ammonium bisulfate aerosol with ammonia provides a means for detecting these substances in air. Field experiments show them to be the dominant substances in the submicrometer, light-scattering aerosol in the St. Louis region.
The presence of fish consumption advisories has a negative impact on fishing. In the St. Louis River, an important natural resource management goal is to reduce or eliminate fish consumption advisories by remediating contaminant sediments and improving aquatic habitat. However, w...
Biology, History and Louis Pasteur: A New Approach to Teaching Science.
Hendrick, Robert
1991-01-01
Presents a rationale for using the history of science in science education. Uses the life and work of Louis Pasteur to illustrate how the history of science can illustrate the nature of science. Describes how Pasteur's bourgeois ideology and ambition influenced his selection of problems to investigate. (over 35 references) (PR)
American Press Coverage of the Execution of Louis XVI: A Lesson Strategy for Gauging Opinion.
Lankiewicz, Donald
1985-01-01
In this unit of study high school students read and discuss U.S. newspaper articles reporting the trial and execution of the French king Louis XVI. Students look for key words and phrases that might indicate a subtle favorable or unfavorable opinion. (RM)
Very Low Birth Weight and Perinatal Periods of Risk: Disparities in St. Louis
Directory of Open Access Journals (Sweden)
Pamela Xaverius
2014-01-01
Full Text Available Objective. Very low birth weight (VLBW is a significant issue in St. Louis, Missouri. Our study evaluated risk factors associated with VLBW in this predominantly urban community. Methods. From 2000 to 2009, birth and fetal death certificates were evaluated (n=160, 189, and mortality rates were calculated for perinatal periods of risk. The Kitagawa method was used to explore fetoinfant mortality rates (FIMR in terms of birth weight distribution and birthweight specific mortality. Multivariable logistic regression was used to assess the magnitude of association of selected risk factors with VLBW. Results. VLBW contributes to 50% of the excess FIMR in St. Louis City and County. The highest proportion of VLBW can be attributed to black maternal race (40.6% in St. Louis City, inadequate prenatal care (19.8%, and gestational hypertension (12.0% among black women. Medicaid was found to have a protective effect for VLBW among black women (population attributable risk (PAR = −14.5. Discussion. Interventions targeting the health of women before and during conception may be most successful at reducing the disparities in VLBW in this population. Interventions geared towards smoking cessation and improvements in Medicaid and prenatal care access for black mothers and St. Louis City residents can greatly reduce VLBW rates.
Current Status of the St. Louis Plan: The Magnet School Component.
Libros, Tracy
1987-01-01
The results and prospects of the magnet school component of desegregation efforts in St. Louis are presented. Demand for magnet seats is outstripping the supply, and thus, the pace of desegregation is limited. But these schools offer an improved educational program and provide more educational choices for families. (VM)
Louis L'Amour's American West. A Sound Filmstrip Program. Study Guide.
Peters, John; Peters, Frances
Adapted from the motion picture based on two of Louis L'Amour's novels of the American West, "The Daybreakers" and "Sackett," this filmstrip program will help secondary students interpret the meaning of the frontier experience in American history. In the first three filmstrips--"Heading West,""Staking…
Ice Events in the St. Louis District. Ice Engineering, Number 20, February 1999
1999-02-01
primarily breakup ice events, no events within the District are specifically identified as breakup events, while 29 are classified freezeup jams. The...75 ice events listed as being “closure” events (when the ice cover freezes at St. Louis) are thought to be primarily due to freezeup pro- cesses. The
2011-05-23
... determination, in accordance with 40 CFR 51.1004(c), suspends the requirements for this area to submit an...; Saint Louis Nonattainment Area; Determination of Attainment of the 1997 Annual Fine Particle Standard... ) nonattainment area in Illinois and Missouri has attained the 1997 annual PM 2.5 National Ambient Air...
Current Status of the St. Louis Plan: The Magnet School Component.
Libros, Tracy
1987-01-01
The results and prospects of the magnet school component of desegregation efforts in St. Louis are presented. Demand for magnet seats is outstripping the supply, and thus, the pace of desegregation is limited. But these schools offer an improved educational program and provide more educational choices for families. (VM)
School Haze: A Response to Louis Menand's View on Multicultural Education.
Franklin, Godfrey; Heath, Inez A.
This essay discusses multicultural education in the context of responding to an article in a national magazine, which critiqued multicultural education. This essay argues that the article, "School Daze" (Louis Menand) in "Harper's Bazaar" magazine in September, 1992, oversimplifies and misrepresents key issues of multicultural education and its…
Mounting a Curricular Revolution: An Interview with Henry Louis Gates, Jr.
von Zastrow, Claus
2009-01-01
This article presents an interview with Henry Louis Gates, Jr., Harvard professor and cultural critic who has captured 25 million viewers with his PBS documentary series, African American Lives (WNET). Using genealogical research and DNA science, Gates traces the family history of 19 famous African Americans. What results is a rich and moving…
Status of Aquatic Non-indigenous Species in the St. Louis River System
As part of a study to develop recommendations for aquatic non-indigenous species (NIS) monitoring in Great Lakes areas at risk of invasion, we conducted comprehensive, multi-gear sampling in the lower St. Louis River in 2005-2007. This effort represents the most spatially and ta...
Compassionate Mind: Implications of a Text Written by Elder Louis Sunchild.
Lightning, Walter C.
1992-01-01
Cree elder Louis Sunchild wrote on the nature of the mind and how to preserve mental health and balance, emphasizing that our minds were created for the exercise of compassion toward each other. Presented in English, Cree syllabics, and Cree roman orthography, with explanations on discourse style and meaning. (SV)
The Reversed Role of Magnets in St. Louis: Implications for Black Student Outcomes
Grooms, Ain A.; Williams, Sheneka M.
2015-01-01
Magnet schools were originally created to attract a diverse student population. Using data from the 23 magnet schools in St. Louis, this longitudinal study is twofold: first, to review the performance outcomes of the magnet schools across a 5-year period, between 2005-2006 and 2009-2010, and second, to examine whether the magnet schools are…
Louis Leprince-Ringuet 1901-2000 A Scientist in the service of Europe
2001-01-01
The renowned French physicist, Louis Leprince-Ringuet, writer, painter and sportsman, who would have been 100 in the spring, died in Paris on 23 December 2000. A convinced European, Louis Leprince-Ringuet supported the creation of CERN. From 1956, he was Vice-Chairman of the Scientific Policy Committee, later becoming its Chairman from 1964 to 1966. After graduating from the Ecole Polytechnique, Louis Leprince-Ringuet began his career in telecommunications as an engineer working on submarine cables. His vocation as a physicist emerged in 1929 when he met Maurice de Broglie, director of a laboratory studying X-rays. For ten years Louis Leprince-Ringuet worked as de Broglie's assistant before moving into the field of cosmic ray research. As director of a research centre devoted to nuclear physics and cosmic rays at the Ecole Polytechnique, he took part in the 1930s in elucidating the nature of these rays, which had previously been unknown. His team pioneered the use of bubble chambers and the observation of hea...
Investigating phenology of larval fishes in St. Louis River estuary shallow water habitats
As part of the development of an early detection monitoring strategy for non-native fishes, larval fish surveys have been conducted since 2012 in the St. Louis River estuary. Survey data demonstrates there is considerable variability in fish abundance and species assemblages acro...
The objective of our study was to determine the relationship between fish tissue stable isotope composition and total mercury or polychlorinated biphenyl (PCB) concentrations in the St. Louis River estuary food web. We sampled two resident fishes, Yellow Perch (Perca flavescens) ...
76 FR 20819 - Manufacturers Railway Company-Discontinuance Exemption-in St. Louis County, MO
2011-04-13
.... Interstate 55 on the west, in St. Louis, Mo. The lines traverse U.S. Postal Service Zip Code 63118. MRS... practice regarding labor conditions in entire system discontinuances. The United Transportation Union, the...). Because this is a discontinuance proceeding and not an abandonment, a trail use/rail banking condition...
Robert Louis Stevenson and Children's Play: The Contexts of "A Child's Garden of Verses."
Rosen, Michael
1995-01-01
Examines a classic text, Robert Louis Stevenson's "A Child's Garden of Verses," within the context of several of Stevenson's own essays. Suggests that unlike many children's books, it was an experiment and one that Stevenson, for various reasons, including his premature death, was never able to adapt for future use. (RS)
Saint-Louis du Sénégal, un enjeu pour le patrimoine mondial
Directory of Open Access Journals (Sweden)
Bernard Toulier
2012-04-01
Full Text Available A l’origine, la ville de Saint–Louis est un comptoir européen installé au XVIIe siècle à l’embouchure du fleuve Sénégal sur l’île de N’dar. Cette île longue et étroite constitue le noyau de la ville coloniale. Les grandes étapes de son urbanisation sont encore lisibles. Elles ont justifié l’inscription du centre historique sur la liste du patrimoine mondial de l’humanité en décembre 2000. L’âge d’or de la ville s’étend durant le dernier quart du XIXe siècle. En 1895, Saint–Louis devient la capitale de l’Afrique Occidentale Française. L’île de Saint–Louis conserve un ensemble urbain sur plan en damiers parmi les plus remarquables de l’Afrique de l’ouest. La sauvegarde de Saint–Louis est un enjeu pour le Ministère de la culture du Sénégal, elle passe par un inventaire systématique du bâti en vue de réaliser une base de données et par des mesures de protection sans pour autant transformer le centre historique en ville musée.First of all, the town of Saint–Louis is a European trading post established in the XVIIth at the mouth of the river Senegal, on N’dar island. This long and narrow island constitutes the historical heart of the old colonial town. Different phases of its expansion are still visible. They explained the inscription of the historical center on the list of mondial heritage, in December 2000. The golden age of the town goes all along the last quarter of the XIXth. In 1895, Saint–Louis became the capital of West French Africa. The town has a very famous chequered urban plan, one of the most remarkable in West Africa. Saint–Louis town’s safeguard is an important stake for the ministry of cultural affairs. It needs an inventory work of architectural heritage in order to set up a database and to take action of preservation, without however changing the historical heart into a museaum–town.
Existence and properties of the Navier-Stokes equations
Zhirkin, Alexey V
2016-01-01
A proof of existence, uniqueness and smoothness of the Navier-Stokes equations is an actual problem, which solution is important for different branches of science. The subject of this study is obtaining the smooth and unique solutions of the three-dimension Stokes-Navier equations for the initial and boundary value problem. The analysis shows that there exist no viscous solutions of the Navier-Stokes equations in three dimensions. The reason is the insufficient capability of the divergence-free velocity field. It is necessary to modify the Navier-Stokes equations for obtaining the desirable solutions. The modified equations describe a three-dimension flow of incompressible fluid which sticks to a body surface. The equation solutions show the resonant blowup of the laminar flow, laminar-turbulent transition, the fluid detachment that opens the way to solve the magnetic dynamo problem.
Polarization speckles and generalized Stokes vector wave: a review [invited
DEFF Research Database (Denmark)
Takeda, Mitsuo; Wang, Wei; Hanson, Steen Grüner
2010-01-01
We review some of the statistical properties of polarization-related speckle phenomena, with an introduction of a less known concept of polarization speckles and their spatial degree of polarization. As a useful means to characterize twopoint vector field correlations, we review the generalized...... Stokes parameters proposed by Korotkova and Wolf, and introduce its time-domain representation to describe the space-time evolution of the correlation between random electric vector fields at two different space-time points. This time-domain generalized Stokes vector, with components similar to those...... of the beam coherence polarization matrix proposed by Gori, is shown to obey the wave equation in exact analogy to a coherence function of scalar fields. Because of this wave nature, the time-domain generalized Stokes vector is referred to as generalized Stokes vector wave in this paper....
Analysis of Stokes flow through periodic permeable tubules
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A.M. Siddiqui
2017-03-01
Full Text Available This article reports the detailed analysis of the Stokes flow through permeable tubes. The objective of this investigation was to search for exact solutions to the Stokes flow and thereby observe the effects on radial flow component, provided the permeability on the tubular surface is an elementary trigonometric function. Mathematical expressions for the pressure distribution, velocity components, volume flux, average wall shear stress and leakage flux are presented explicitly. Graphical analysis of the fluid flow is presented for a set of parametric values. Important conclusions are drawn for Stokes flow through tubes with low as well as high permeability. The classical Poiseuille flow is presented as a limiting case of this immense study of Stokes flow.
Product Integral Formalism and Non-Abelian Stokes Theorem
Karp, R L; Rno, J S; Karp, Robert L.; Mansouri, Freydoon; Rno, Jung S.
1999-01-01
We make use of the properties of product integrals to obtain a surface product integral representation for the Wilson loop operator. The result can be interpreted as the non-abelian version of Stokes' theorem.
Navier-Stokes equations an introduction with applications
Łukaszewicz, Grzegorz
2016-01-01
This volume is devoted to the study of the Navier–Stokes equations, providing a comprehensive reference for a range of applications: from students to engineers and mathematicians involved in research on fluid mechanics, dynamical systems, and mathematical modeling. Equipped with only a basic knowledge of calculus, functional analysis, and partial differential equations, the reader is introduced to the concept and applications of the Navier–Stokes equations through a series of fully self-contained chapters. Including lively illustrations that complement and elucidate the text, and a collection of exercises at the end of each chapter, this book is an indispensable, accessible, classroom-tested tool for teaching and understanding the Navier–Stokes equations. Incompressible Navier–Stokes equations describe the dynamic motion (flow) of incompressible fluid, the unknowns being the velocity and pressure as functions of location (space) and time variables. A solution to these equations predicts the behavior o...
A GPU-Computing Approach to Solar Stokes Profile Inversion
Harker, Brian J
2012-01-01
We present a new computational approach to the inversion of solar photospheric Stokes polarization profiles, under the Milne-Eddington model, for vector magnetography. Our code, named GENESIS (GENEtic Stokes Inversion Strategy), employs multi-threaded parallel-processing techniques to harness the computing power of graphics processing units GPUs, along with algorithms designed to exploit the inherent parallelism of the Stokes inversion problem. Using a genetic algorithm (GA) engineered specifically for use with a GPU, we produce full-disc maps of the photospheric vector magnetic field from polarized spectral line observations recorded by the Synoptic Optical Long-term Investigations of the Sun (SOLIS) Vector Spectromagnetograph (VSM) instrument. We show the advantages of pairing a population-parallel genetic algorithm with data-parallel GPU-computing techniques, and present an overview of the Stokes inversion problem, including a description of our adaptation to the GPU-computing paradigm. Full-disc vector ma...
Coherent anti-Stokes Raman spectroscopy: Understanding the essentials
Ariunbold, Gombojav O.; Altangerel, Narangerel
2016-12-01
This paper is a brief overview to coherent anti- Stokes Raman spectroscopic technique and introduces the strengths and barriers to its use all based on the interpretation of simple theoretical formulae. The use of the Gaussian ultrashort pulses is highlighted as a practical elucidatory reconstruction tool of coherent Raman spectra. The paper presents the integral formulae for coherent anti-Stokes and Stokes Raman scattering, and discusses the closed-form solutions, its complex error function, and the delay time formula for enhancement of the inferred pure coherent Raman spectra. As an example, the timeresolved coherent Stokes Raman scattering experimental observations are quantitatively elucidated.Understanding the essentials of coherent Raman spectroscopy, therefore, promotes the importance of a number of experiments including the ones utilizing a broadband excitation with a narrowband delayed probing for successful background suppression.
Analysis of Subgrid Stabilization Method for Stokes-Darcy Problems
Directory of Open Access Journals (Sweden)
Kamel Nafa
2016-01-01
Full Text Available A number of techniques, used as remedy to the instability of the Galerkin finite element formulation for Stokes like problems, are found in the literature. In this work we consider a coupled Stokes-Darcy problem, where in one part of the domain the fluid motion is described by Stokes equations and for the other part the fluid is in a porous medium and described by Darcy law and the conservation of mass. Such systems can be discretized by heterogeneous mixed finite elements in the two parts. A better method, from a computational point of view, consists in using a unified approach on both subdomains. Here, the coupled Stokes-Darcy problem is analyzed using equal-order velocity and pressure approximation combined with subgrid stabilization. We prove that the obtained finite element solution is stable and converges to the classical solution with optimal rates for both velocity and pressure.
[Louis Maurice Champagne and the "Ecole dentaire française"].
Rousseau, Claude
2002-01-01
The Royal Edict of Louis XIV had created a new category of practitioners, "The Teeth Experts", and at the dawn of the second half of the 19th century, France had no dental school nor specific legislation. The situation worsened when many American dentists settled in France. Thus the creating of the "Ecole dentaire de Paris" in 1880 constituted a significant event which was followed by the opening of the "Ecole Dentaire de France" in 1884 and of the "Ecole Dentaire Française" in 1896. Louis Maurice Champagne will be its director from 1926. At the St Ouen Jules Vallés Market, we fortuitously discovered a framed document containing three photographs of Louis Maurice Champagne's surgery located, 3 Place de la Madeleine in Paris. Thanks to his son and through various documents, we could trace the exceptional professional carrier of this practitioner who eventually bought the "Ecole Dentaire Française" from Dr Louis-Jules Rousseau. Then, we discuss the legal frame work of the 1892 law created the "Chirurgien-dentiste" diploma and we describe the scientific and practical teaching for the "Ecole dentaire française". The operating layout of the clinical rooms is presented by opposing the ergonomic aspect of the demonstration surgery of the director and the two large operative dentistry rooms used for students. We conclude by emphasizing Louis Maurice Champagne's determination to overcome adversity which was peculiar to him as a young orphan immigrant without resources. To solve the problem of the "Chirurgien Dentiste" statute considered by its promoters as a stage of transition towards fuller reforms, we present various projects like from Dr Hulin's. This practitioner presided the Dental Section of the Medical Council Order before being voted in the first President of the "Chirurgien Dentiste" National Council Order in 1945. In 1942 he was the first to advocate a legislation based on the independence of the dental profession, still in force nowadays.
DIVERGENCE - FREE WAVELET SOLUTION TO THE STOKES PROBLEM
Institute of Scientific and Technical Information of China (English)
Yingchun Jiang
2007-01-01
In this paper, we use divergence-free wavelets to give an adaptive solution to the velocity field of the Stokes problem. We first use divergence-free wavelets to discretize the divergence-free weak formulation of the Stokes problem and obtain a discrete positive definite linear system of equations whose coefficient matrix is quasi-sparse; Secondly, an adaptive scheme is used to solve the discrete linear system of equations and the error estimation and complexity analysis are given.
Compressible Navier-Stokes Equations with Revised Maxwell's Law
Hu, Yuxi; Racke, Reinhard
2017-03-01
We investigate the compressible Navier-Stokes equations where the constitutive law for the stress tensor given by Maxwell's law is revised to a system of relaxation equations for two parts of the tensor. The global well-posedness is proved as well as the compatibility with the classical compressible Navier-Stokes system in the sense that, for vanishing relaxation parameters, the solutions to the Maxwell system are shown to converge to solutions of the classical system.
Stokes-Mueller matrix polarimetry system for glucose sensing
Phan, Quoc-Hung; Lo, Yu-Lung
2017-05-01
A Stokes-Mueller matrix polarimetry system consisting of a polarization scanning generator (PSG) and a high-accuracy Stokes polarimeter is used to sense the glucose concentration in aqueous solutions with and without scattering effects, respectively. In the proposed system, an electro-optic (EO) modulator driven by a saw-tooth waveform voltage is used to perform full state of polarization (linear/circular) scanning, while a self-built Stokes polarimeter is used to obtain dynamic measurements of the output polarized light intensity. It is shown that the measured output Stokes vectors have an accuracy of 10-4, i.e., one order higher than that of existing commercial Stokes polarimeters. The experimental results show that the optical rotation angle varies linearly with the glucose concentration over the range of 0-0.5 g/dl. Moreover, glucose sensing is successfully achieved at concentrations as low as 0.02 g/dl with a resolution of 10-6 deg/mm and an average deviation of 10-4 deg. In general, the polarimetry system proposed in this study provides a fast and reliable method for measuring the Stokes vectors, and thus has significant potential for biological sensing applications.
Singularity of Navier-Stokes Equations Leading to Turbulent Transition
Dou, Hua-Shu; Fluid Mechanics Research Team
2014-11-01
As is well known, there is discontinuity during the transition from laminar flow to turbulence in the time-averaged Navier-Stokes equations. In other words, singularity may implicitly exist in the Navier-Stokes equations. Transition of a laminar flow to turbulence must be implemented via the singularity. However, how the singularity of Navier-Stokes equations is related to the turbulent transition is not understood. In this study, the singularity possibly hidden in the Navier-Stokes equation is exactly derived by mathematical treatment. Then, it is found that for pressure driven flows, the singularity of Navier-Stokes equations corresponds to the inflection point on the velocity profile. Since the rate of amplification to a disturbance at the inflection point is infinite, the laminar flow is able to involve into turbulence at this point firstly at a sufficient high Reynolds number. This is the reason why turbulent spot is formed at the location of inflection point. It is further demonstrated that the existence of the singularity in the time-averaged Navier-Stokes equations is the necessary and sufficient condition for the turbulent transition in pressure driven flows. These results agrees well with the findings from the recent proposed energy gradient method. Professor in Fluid Mechanics; AIAA Associate Fellow.
Stokes coupling method for the exterior flowPart III: regularity
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Based on the Stokes coupling method for solving the two-dimensional exterior unsteady Navier-Stokes equations, the existence of the strong solution of the Stokes coupling equations is proven. And the regularity of the solution for the reduced Stokes coupling equations is discussed.
Androutsos, Georges
2002-02-01
The great majority of historians agree that the marriage of Louis XVI and Marie-Antoinette was only consumated seven years after the official ceremony. This delay could have been due to a genital malformation (phimosis) of Louis XVI, a strict religious education, a traumatic childhood and the young age of the two spouses, factors that may have inhibited their sexuality. In this article, the authors try to determine whether Louis XVI was able to overcome his sexual difficulties following an operation (circumcision) or as a result of spontaneous cure.
Picosecond anti-Stokes generation in a photonic-crystal fiber for interferometric CARS microscopy.
Andresen, Esben Ravn; Keiding, Søren Rud; Potma, Eric Olaf
2006-08-07
We generate tunable picosecond anti-Stokes pulses by four-wave mixing of two picosecond pump and Stokes pulse trains in a photonic-crystal fiber. The visible, spectrally narrow anti-Stokes pulses with shifts over 150 nm are generated without generating other spectral features. As a demonstration, we employ the generated anti-Stokes pulses as reference pulses in an interferometric coherent anti-Stokes Raman scattering imaging experiment showing that interpulse coherence among the pump, Stokes and anti-Stokes beams is retained.
Directory of Open Access Journals (Sweden)
Henriette Litta
2009-04-01
Full Text Available Review of the edited volume: Louis Lebel, John Dore, Rajesh Daniel, and Yang Saing Koma (eds.: Democratizing Water Governance in the Mekong Region Chiang Mai, Thailand: Mekong Press, 2007, ISBN 978-974-9511-25-1, 304 pages Besprechung des Sammelbandes: Louis Lebel, John Dore, Rajesh Daniel, and Yang Saing Koma (Hrsg.: Democratizing Water Governance in the Mekong Region Chiang Mai, Thailand: Mekong Press, 2007, ISBN 978-974-9511-25-1, 304 Seiten.
Castelluccio, Stéphane
2015-01-01
Cher Monsieur, Il est toujours flatteur et enrichissant d’être lu et critiqué avec tant de pertinence par un si grand historien de l’art, spécialiste reconnu de l’ameublement de Marly, dont la seule publication un peu consistante à ce sujet est restée dans toutes les mémoires pour sa rigueur scientifique et sa précision (Bentz (Bruno), « Le château de Marly sous Louis XVI », Gazette des Beaux-Arts, mars 1991, p. 113-122). La profondeur de ses critiques et remarques (index, bibliographie, comm...
解读Louis Vuitton打造顶级品牌形象之谜%Unscramble the Top Brand Image of Louis Vuitton
Institute of Scientific and Technical Information of China (English)
杨静蕊
2015-01-01
Brand image is core of competitive power of an enterprise. In this paper, the top luxury bag brand was analyzed from brand image, the most important part for establishing brand, in or-der to give some enlightenment to our national enterprises.%品牌形象是企业竞争力的核心。本文从树立品牌最为重要的部分--品牌形象入手，对国际顶级箱包品牌Louis Vuitton进行剖析，企图找到对民族企业有所启迪的东西。
Jehaes, E; Decorte, R; Peneau, A; Petrie, J H; Boiry, P A; Gilissen, A; Moisan, J P; Van den Berghe, H; Pascal, O; Cassiman, J J
1998-01-01
Carl Wilhelm Naundorff was buried in 1845 in Delft as Louis Charles, Duc de Normandie, 'Louis XVII'. However, the son of Louis XVI and Marie-Antoinette-Louis XVII--officially died in the Temple of Paris in 1795. In order to resolve the identity of Naundorff, mitochondrial DNA (mtDNA) D-loop sequences of his remains were compared with the sequences obtained from the hairs of two sisters of Marie-Antoinette, Marie-Antoinette herself, and with the sequences obtained from DNA samples of two living maternal relatives. The mtDNA sequence of a bone sample from Naundorff showed two nucleotide differences from the sequences of the three sisters and four differences from the sequences of living maternal relatives. Based on this evidence it becomes very unlikely that Naundroff is the son of Marie-Antoinette.
Chery, Aurore
2016-01-01
International audience; Book review : Fashion Victims. Dress at the Court of Louis XVI and Marie-Antoinette. By Kimberly Chrisman-Campbell. New Haven: Yale University Press, 2015. ISBN 978-0-300-15438-2. 352 pp. £35.
Godoy, Gerardo A; Tarradath, Ewart
2010-02-01
Louis Daniel Beauperthuy was a pioneer of microbiology in Venezuela where he developed microscopic and clinical research together with academic and scientific observation related to leprosy and the role of insects in the transmission of febrile illnesses.
Louis Vivet, un cas paradigmatique des personnalités multiples et de la méthode cathartique
Directory of Open Access Journals (Sweden)
Stéphane Laurens
2006-01-01
Full Text Available A clinical case of Louis Vivet, described by Bourru and Burot (1888, contributed to elaborate the concepts of multiple personality and cathartic method. The authors present this clinical case, the cultural context of this mental illness, and the relevant theories. The genetic analysis of Louis Vivet's iatrogenic disorder or transient mental illness (Hacking, 2002 shows how the dominant theories on identity and memory contributed to construct the symptoms observed by Bourru and Burot (1888 and validated the therapeutic methods.
Moreland-Russell, Sarah; Cyr, Julianne; Benson, Peter; Colditz, Graham; Pulley, Deren; Barnoya, Joaquin
2014-01-01
This cross- sectional study provides information about secondhand smoke exposure across the St. Louis metro area and perceptions and attitudes about tobacco and health within the local hospitality industry. Results from this study support the need for passage and implementation of comprehensive smoke-free laws throughout Missouri, particularly in St. Louis City and County where efforts to pass comprehensive smoke-free laws have been unsuccessful . PMID:23362653
Louis Vivet, un cas paradigmatique des personnalités multiples et de la méthode cathartique
Stéphane Laurens; Toshiaki Kozakaï
2006-01-01
A clinical case of Louis Vivet, described by Bourru and Burot (1888), contributed to elaborate the concepts of multiple personality and cathartic method. The authors present this clinical case, the cultural context of this mental illness, and the relevant theories. The genetic analysis of Louis Vivet's iatrogenic disorder or transient mental illness (Hacking, 2002) shows how the dominant theories on identity and memory contributed to construct the symptoms observed by Bourru and Burot (1888) ...
A new MHD-assisted Stokes inversion technique
Riethmüller, T L; Barthol, P; Gandorfer, A; Gizon, L; Hirzberger, J; van Noort, M; Rodríguez, J Blanco; Iniesta, J C Del Toro; Suárez, D Orozco; Schmidt, W; Pillet, V Martínez; Knölker, M
2016-01-01
We present a new method of Stokes inversion of spectropolarimetric data and evaluate it by taking the example of a SUNRISE/IMaX observation. An archive of synthetic Stokes profiles is obtained by the spectral synthesis of state-of-the-art magnetohydrodynamics (MHD) simulations and a realistic degradation to the level of the observed data. The definition of a merit function allows the archive to be searched for the synthetic Stokes profiles that match the observed profiles best. In contrast to traditional Stokes inversion codes, which solve the Unno-Rachkovsky equations for the polarized radiative transfer numerically and fit the Stokes profiles iteratively, the new technique provides the full set of atmospheric parameters. This gives us the ability to start an MHD simulation that takes the inversion result as initial condition. After a relaxation process of half an hour solar time we obtain physically consistent MHD data sets with a target similar to the observation. The new MHD simulation is used to repeat t...
A New MHD-assisted Stokes Inversion Technique
Riethmüller, T. L.; Solanki, S. K.; Barthol, P.; Gandorfer, A.; Gizon, L.; Hirzberger, J.; van Noort, M.; Blanco Rodríguez, J.; Del Toro Iniesta, J. C.; Orozco Suárez, D.; Schmidt, W.; Martínez Pillet, V.; Knölker, M.
2017-03-01
We present a new method of Stokes inversion of spectropolarimetric data and evaluate it by taking the example of a Sunrise/IMaX observation. An archive of synthetic Stokes profiles is obtained by the spectral synthesis of state-of-the-art magnetohydrodynamics (MHD) simulations and a realistic degradation to the level of the observed data. The definition of a merit function allows the archive to be searched for the synthetic Stokes profiles that best match the observed profiles. In contrast to traditional Stokes inversion codes, which solve the Unno-Rachkovsky equations for the polarized radiative transfer numerically and fit the Stokes profiles iteratively, the new technique provides the full set of atmospheric parameters. This gives us the ability to start an MHD simulation that takes the inversion result as an initial condition. After a relaxation process of half an hour solar time we obtain physically consistent MHD data sets with a target similar to the observation. The new MHD simulation is used to repeat the method in a second iteration, which further improves the match between observation and simulation, resulting in a factor of 2.2 lower mean {χ }2 value. One advantage of the new technique is that it provides the physical parameters on a geometrical height scale. It constitutes a first step toward inversions that give results consistent with the MHD equations.
Stokes tomography of radio pulsar magnetospheres. II. Millisecond pulsars
Chung, C T Y
2011-01-01
The radio polarization characteristics of millisecond pulsars (MSPs) differ significantly from those of non-recycled pulsars. In particular, the position angle (PA) swings of many MSPs deviate from the S-shape predicted by the rotating vector model, even after relativistic aberration is accounted for, indicating that they have non-dipolar magnetic geometries, likely due to a history of accretion. Stokes tomography uses phase portraits of the Stokes parameters as a diagnostic tool to infer a pulsar's magnetic geometry and orientation. This paper applies Stokes tomography to MSPs, generalizing the technique to handle interpulse emission. We present an atlas of look-up tables for the Stokes phase portraits and PA swings of MSPs with current-modified dipole fields, filled core and hollow cone beams, and two empirical linear polarization models. We compare our look-up tables to data from 15 MSPs and find that the Stokes phase portraits for a current-modified dipole approximately match several MSPs whose PA swings ...
Ambrogio A. Caiani, Louis XVI and the French Revolution 1789-1792
Becquet , Hélène
2014-01-01
Dressant le constat d’un vide historiographique sur le règne constitutionnel de Louis XVI et son système de représentation, Ambrogio A. Caiani se propose de prendre comme objet d’étude la cour de Louis XVI de 1789 à 1792 et de montrer comment celle-ci contribue à la radicalisation révolutionnaire et, finalement, à la chute de la monarchie. Compte tenu de l’état lacunaire des sources, l’auteur a préféré présenter une série d’études de cas plutôt qu’une étude systématique de son objet. Bien que...
[About two unpublished autographs of Louis Pasteur belonging to the Academie national de pharmacie].
Storck, J
1997-01-01
Two unpublished autographs of Louis Pasteur, dated respectively november 26th 1853 and december 22nd 1853 in Strasbourg, were found in unclassified archives of the Academie nationale de pharmacie - Paris. They are described in the paper. They are related to the prize of F 1500 given to him by the Societe de pharmacie, the previous name of the Academy. This award concerned his famous studies on the racemic or paratartric acid.
St. Louis Metro Biodiesel (B20) Transit Bus Evaluation: 12-Month Final Report
Energy Technology Data Exchange (ETDEWEB)
Barnitt, R.; McCormick, R. L.; Lammert, M.
2008-07-01
The St. Louis Metro Bodiesel Transit Bus Evaluation project is being conducted under a Cooperative Research and Development Agreement between NREL and the National Biodiesel Board to evaluate the extended in-use performance of buses operating on B20 fuel. The objective of this research project is to compare B20 and ultra-low sulfur diesel buses in terms of fuel economy, veicles maintenance, engine performance, component wear, and lube oil performance.
Target Population Involvement in Urban Ciclovias: A Preliminary Evaluation of St. Louis Open Streets
Hipp, J. Aaron; Eyler, Amy A.; Kuhlberg, Jill A.
2012-01-01
Ciclovias are active street events when roads are open to walkers, cyclists, and families and closed to automobiles. Over 70 cities in the USA have implemented ciclovias to promote physical activity. The authors evaluated four events during 2010 to determine what activities participants perform and who is attending. For two ciclovia events in St. Louis, Missouri, observation reports of activities, gender, and age of 1,452 participants were collected, and 82 adults were interviewed via direct ...
Directory of Open Access Journals (Sweden)
Matías Abeijón
2013-06-01
Full Text Available Este trabajo tiene como objetivo reconstruir el itinerario intelectual de la obra de Louis Althusser respecto a sus relaciones con el psicoanálisis y la psicología. De acuerdo con nuestra hipótesis, Althusser recurrió al psicoanálisis con el objetivo de darle un uso particular: impugnar las ciencias psicológicas y la noción burguesa de sujeto. Así, el psicoanálisis habría servido al desarrollo de sus conocidas críticas a la categoría de sujeto, en tanto este se presentaría como una alternativa a las lecturas que consideran al “yo” como dominio de instancia psíquica // The objective of this paper is to reconstruct the intellectual itinerary of Louis Althusser’s work regarding its relationship to psychoanalysis and psychology. According to our more general hypothesis, Althusser resorted to psychoanalysis in order to use it in a particular way: to disprove both the psychological sciences and the bourgeois notion of subject. Hence, psychoanalysis would have been useful to the development of his well-known criticism of the category of subject. This would be presented as an alternative to the readings of the "ego" as domain of psychic instance.
Genetic analysis of the presumptive blood from Louis XVI, King of France.
Lalueza-Fox, Carles; Gigli, Elena; Bini, Carla; Calafell, Francesc; Luiselli, Donata; Pelotti, Susi; Pettener, Davide
2011-11-01
A text on a pyrographically decorated gourd dated to 1793 explains that it contains a handkerchief dipped with the blood of Louis XVI, king of France, after his execution. Biochemical analyses confirmed that the material contained within the gourd was blood. The mitochondrial DNA (mtDNA) hypervariable region 1 (HVR1) and 2 (HVR2), the Y-chromosome STR profile, some autosomal STR markers and a SNP in HERC2 gene associated to blue eyes, were retrieved, and some results independently replicated in two different laboratories. The uncommon mtDNA sequence retrieved can be attributed to a N1b haplotype, while the novel Y-chromosome haplotype belongs to haplogroup G2a. The HERC2 gene showed that the subject analyzed was a heterozygote, which is compatible with a blue-eyed person, as king Louis XVI was. To confirm the identity of the subject, an analysis of the dried heart of his son, Louis XVII, could be undertaken.
Genomic analysis of the blood attributed to Louis XVI (1754-1793), king of France.
Olalde, Iñigo; Sánchez-Quinto, Federico; Datta, Debayan; Marigorta, Urko M; Chiang, Charleston W K; Rodríguez, Juan Antonio; Fernández-Callejo, Marcos; González, Irene; Montfort, Magda; Matas-Lalueza, Laura; Civit, Sergi; Luiselli, Donata; Charlier, Philippe; Pettener, Davide; Ramírez, Oscar; Navarro, Arcadi; Himmelbauer, Heinz; Marquès-Bonet, Tomàs; Lalueza-Fox, Carles
2014-04-24
A pyrographically decorated gourd, dated to the French Revolution period, has been alleged to contain a handkerchief dipped into the blood of the French king Louis XVI (1754-1793) after his beheading but recent analyses of living males from two Bourbon branches cast doubts on its authenticity. We sequenced the complete genome of the DNA contained in the gourd at low coverage (~2.5×) with coding sequences enriched at a higher ~7.3× coverage. We found that the ancestry of the gourd's genome does not seem compatible with Louis XVI's known ancestry. From a functional perspective, we did not find an excess of alleles contributing to height despite being described as the tallest person in Court. In addition, the eye colour prediction supported brown eyes, while Louis XVI had blue eyes. This is the first draft genome generated from a person who lived in a recent historical period; however, our results suggest that this sample may not correspond to the alleged king.
The mysterious fate of la Bibliothèque de Louis Pasteur (1822-1895).
Oertling, Sarita B; Marlin, Robert O; Goldman, Armond S
2014-11-01
In addition to the holdings at Bibliothèque Nationale de France and Musée du Pasteur Institut à Paris, major parts of la Bibliothèque de Louis Pasteur are in four institutions in the United States - Reynolds Historical Library at the University of Alabama at Birmingham, Alabama; Burndy Library on the History of Science and Technology at Huntington Library in San Marino, California; Harry Ransom Humanities Research Center at University of Texas in Austin, Texas; and Truman G Blocker History of Medicine Collections, The Moody Medical Library, University of Texas Medical Branch, Galveston, Texas. The circuitous paths that led each part of la Bibliothèque de Louis Pasteur to their present locations were traced and the lives of key individuals in medicine, science and the humanities who obtained these valuable documents were recounted. The documents in each institution were discussed and a plan was considered to make them accessible to scholars who wish to further explore the life of Louis Pasteur.
Monoclonal antibody against Saint Louis encephalitis prM viral protein.
Pupo-Antúnez, M; Vázquez, S; Sosa, A L; Caballero, Y; Vásquez, Y; Morier, L; Álvarez, M; Guzmán, M G
2015-06-15
Saint Louis encephalitis virus belongs to Flavivirus genus; Flaviviridae family jointly with other medically important flaviviruses including dengue virus and West Nile virus. The biological properties and functions of prM flavivirus protein are under investigation due to its importance in the generation of infectious virion and host interactions. Monoclonal antibodies have become powerful tools in this approach. Also the use of monoclonal antibodies has been successfully applied for antigenic analysis, clinical diagnosis and treatments. Here, using an immunofluorescence assay we describe a monoclonal antibody (mAb 3D2) that uniquely recognizes native prM Saint Louis encephalitis virus protein expressed in either C6/36-HT or Vero cells. In conclusion, mAb3D2 has significant potential for use in (a) the diagnosis of infections caused by this virus and (b) therapeutic use to treat patients infected by this virus and fundamental research to understand the role of the prM in the Saint Louis encephalitis virus infectious process.
Long Term Stewardship Challenges at the St. Louis District FUSRAP Sites
Energy Technology Data Exchange (ETDEWEB)
Dell' Orco, L.; Chambers, D.
2002-02-27
Non-Federally owned radioactively contaminated sites in St. Louis, Missouri are currently being remediated by the St. Louis District Corps of Engineers under the Formerly Utilized Sites Remedial Action Program (FUSRAP). When FUSRAP remediation is complete, inaccessible soils which have levels of contamination greater than unrestricted use standards, will remain. The purpose of this paper is to document the initial challenges facing the project team during its development of the Long Term Stewardship plan for the management of these soils. These soils are located under buildings, roads, railroads and bridges. The Long Term Stewardship plan for the majority of the sites is being developed simultaneously with the remedy selection process. A living document, it will ultimately document the remedial action end state and location of inaccessible soils and implement the plan for ensuring these soils are not a threat to human health and the environment. Although these soils are protective in their current configuration, at some point in time, when activities such as maintenance, utility or property improvement occur, the soils will become accessible and need to be addressed by the federal government. Up until that point in time they will need to be effectively managed to ensure they remain protective. The St. Louis District is in the process of collaboratively developing this plan with its regulators, affected stakeholders and interested parties.
Combined Stokes vector and Mueller matrix polarimetry for materials characterization.
Hall, Shaun A; Hoyle, Marc-André; Post, Joshua S; Hore, Dennis K
2013-08-06
A robust way of measuring the optical properties of any material is to interrogate it with light of different polarizations. The 16-element Mueller matrix provides the most complete description of the optical properties of a sample based on its ability to alter the polarization state of transmitted or reflected light. This is valuable for ordered and isotropic materials alike. Similarly, the 4-element Stokes vector is the most complete description of the polarization of a light beam, including any depolarization effects. While the Mueller matrix offers the most chemical and physical insight, the Stokes vectors are easier to obtain, and there are more schemes for measuring them quickly in situations where time resolution is important. We describe a method where any Stokes polarimeter may be adapted to obtain Mueller matrices and discuss various approaches for achieving better time resolution.
Normalized Stokes operators for polarization correlations of entangled optical fields
Żukowski, Marek; Laskowski, Wiesław; Wieśniak, Marcin
2017-04-01
Stokes parameters are a standard tool in quantum optics. They involve averaged intensities at exits of polarizers. If the overall measured intensity fluctuates, as, e.g., for states with undefined photon numbers, the instances of its increased value contribute more to the parameters. One can introduce normalized quantum Stokes operators. Operationally, for a given single run of the experiment, their values are differences of measured intensities (or photon numbers) at the two exits of a polarizer divided by their sum. Effects of intensity fluctuations are removed. Switching to normalized Stokes operators results in more sensitive entanglement conditions. We also show a general method of deriving an entanglement indicator for optical fields which use polarization correlations, which starts with any two-qubit entanglement witness. This allows one to vastly expand the family of such indicators.
Singularity and Breaking of the Third Order Stokes Waves
Institute of Scientific and Technical Information of China (English)
孙孚; 高山; 王伟; 钱成春
2003-01-01
In this paper, the fact is revealed that the surface elevation of the third order Stokes waves in implicit form could have no solution or have simultaneously a trivial one and a singular one on certain conditions. Based on this fact, the relative breaking width, a more reasonable quantity in agreement with the definition of whitecapping coverage rate, is obtained directly from the assumption that no solution means breaking. The implications of the singular solution existing in the third order stokes waves are also discussed briefly.
Medidas de viscosidad: viscosímetro. Ley de Stokes
Pérez Rodríguez, Jorge; Miret Marí, Juan José; Espinosa Tomás, Julián; Caballero Caballero, María Teresa
2010-01-01
Guión de la pŕactica de Física de primero del grado de Óptica y Optometría "Medidas de viscosidad: Viscosímetro. Ley de Stokes" Objetivos - Medir la viscosidad de un líquido problema con el viscosímetro. - Señalar la ventaja de la determinación de magnitudes relativas. - Medir la viscosidad de un líquido problema aplicando la ley de Stokes.
On the Stokes matrices of the $tt^*$-Toda equation
Horocholyn, Stefan
2016-01-01
We derive a formula for the signature of the symmetrized Stokes matrix $\\cal{S}+\\cal{S}^\\mathrm{T}$ for the $tt^*$-Toda equation. As a corollary, we verify a conjecture of Cecotti and Vafa regarding when $\\cal{S}+\\cal{S}^\\mathrm{T}$ is positive definite, reminiscent of a formula of Beukers and Heckmann for the generalized hypergeometric equation. The condition that $\\cal{S}+\\cal{S}^\\mathrm{T}$ is positive definite is prominent in the work of Cecotti and Vafa on the $tt^*$ equation; we show that the Stokes matrices $\\cal{S}$ satisfying this condition are parameterized by the points of an open convex polytope.
Error estimation and adaptivity in Navier-Stokes incompressible flows
Wu, J.; Zhu, J. Z.; Szmelter, J.; Zienkiewicz, O. C.
1990-07-01
An adaptive remeshing procedure for solving Navier-Stokes incompressible fluid flow problems is presented in this paper. This procedure has been implemented using the error estimator developed by Zienkiewicz and Zhu (1987, 1989) and a semi-implicit time-marching scheme for Navier-Stokes flow problems (Zienkiewicz et al. 1990). Numerical examples are presented, showing that the error estimation and adaptive procedure are capable of monitoring the flow field, updating the mesh when necessary, and providing nearly optimal meshes throughout the calculation, thus making the solution reliable and the computation economical and efficient.
Topology Optimization of Large Scale Stokes Flow Problems
DEFF Research Database (Denmark)
Aage, Niels; Poulsen, Thomas Harpsøe; Gersborg-Hansen, Allan
2008-01-01
This note considers topology optimization of large scale 2D and 3D Stokes flow problems using parallel computations. We solve problems with up to 1.125.000 elements in 2D and 128.000 elements in 3D on a shared memory computer consisting of Sun UltraSparc IV CPUs.......This note considers topology optimization of large scale 2D and 3D Stokes flow problems using parallel computations. We solve problems with up to 1.125.000 elements in 2D and 128.000 elements in 3D on a shared memory computer consisting of Sun UltraSparc IV CPUs....
Geometric Origin of Stokes Phenomenon for de Sitter Radiation
Kim, Sang Pyo
2013-01-01
We propose a geometric interpretation for the Stokes phenomenon in de Sitter spacetime that particles are produced in even dimensions but not in odd dimensions. The scattering amplitude for a quantum field between the in-vacuum and the transported one along a closed path in the complex-time plane gives the particle-production rate that explains not only the Boltzmann factor from the simple pole at infinity, corresponding to the cosmological horizon, but also the sinusoidal behavior from simple poles at the north and south poles of the Euclidean geometry. The Stokes phenomenon is a consequence of interference among four independent closed paths in the complex plane.
Discretizations in isogeometric analysis of Navier-Stokes flow
DEFF Research Database (Denmark)
Nielsen, Peter Nørtoft; Gersborg, Allan Roulund; Gravesen, Jens;
2011-01-01
for the simplified Stokes problem confirm the existence of many stable discretizations of the velocity and pressure spaces, and in particular show that stability may be achieved by means of knot refinement of the velocity space. Error convergence studies for the full Navier-Stokes problem show optimal convergence...... rates for this type of discretizations. Finally, a comparison of the results of the method to data from the literature for the lid-driven square cavity for Reynolds numbers up to 10,000 serves as benchmarking of the discretizations and confirms the robustness of the method. © 2011 Elsevier B.V....
Localized thermal mapping using coherent anti-Stokes Raman spectroscopy.
Beier, Hope T; Noojin, Gary D; Rockwell, Benjamin A
2012-08-01
Coherent anti-Stokes Raman scattering (CARS) spectroscopy is explored as a tool for obtaining micro-scale thermal measurements. A single femtosecond oscillator is used to pump a photonic crystal fiber to provide the broadband Stokes pulse. The CARS signals from the broad OH-stretching modes between 3000 and 3600 cm(-1) are shown to correlate with temperature with an accuracy of ± 1°C for water and ± 1.5°C for phosphate-buffered saline. Local variation of temperature is mapped on a microscopic level, using black-dyed microspheres as thermal sources.
Institute of Scientific and Technical Information of China (English)
2007-01-01
In this paper, the Dirichlet problem of Stokes approximate of non-homogeneous incompressible Navier-Stokes equations is studied. It is shown that there exist global weak solutions as well as global and unique strong solution for this problem, under the assumption that initial density ρ0(x) is bounded away from 0 and other appropriate assumptions (see Theorem 1 and Theorem 2). The semi-Galerkin method is applied to construct the approximate solutions and a prior estimates are made to elaborate upon the compactness of the approximate solutions.
Instability theory of the Navier-Stokes-Poisson equations
Jang, Juhi
2011-01-01
The stability question of the Lane-Emden stationary gaseous star configurations is an interesting problem arising in astrophysics. We establish both linear and nonlinear dynamical instability results for the Lane-Emden solutions in the framework of the Navier-Stokes-Poisson system with adiabatic exponent $6/5 < \\gamma < 4/3$.
ANALYSIS OF SOME ASSUMPTIONS OF NAVIER-STOKES EQUATION
Directory of Open Access Journals (Sweden)
Budarin V.
2010-08-01
Full Text Available Several stages of the derivation of Navier-Stokes equations in coordinate form are analyzed. The purpose of the analysis is the determination of long-term problems of system closure, of reasons for differences of exact solutions for low Reynolds numbers and the appearance of unstable solutions using computer programs.
Assessing the Polarization of a Quantum Field from Stokes Fluctuations
DEFF Research Database (Denmark)
Klimov, A. B.; Björk, G.; Söderholm, J.
2010-01-01
We propose an operational degree of polarization in terms of the variance of the Stokes vector minimized over all the directions of the Poincaré sphere. We examine the properties of this second-order definition and carry out its experimental determination. Quantum states with the same standard...
On iterative methods for the incompressible Stokes problem
Rehman, M. ur; Geenen, T.; Vuik, C.; Segal, G.; MacLachlan, S.P.
2011-01-01
In this paper, we discuss various techniques for solving the system of linear equations that arise from the discretization of the incompressible Stokes equations by the finite-element method. The proposed solution methods, based on a suitable approximation of the Schur-complement matrix, are shown t
Inversions of High-Cadence SOLIS-VSM Stokes Observations
Fischer, C.E.; Keller, C.U.; Snik, F.
2008-01-01
We have processed full-Stokes observations made with the SOLIS-VSM using Fe I 630.15 and Fe I 630.25 nm. The data have high spectral and temporal resolution, moderate spatial resolution, and large polarimetric sensitivity and accuracy. We use the code LILIA, an LTE inversion code written by Socas-Na
Stokes tomography of radio pulsar magnetospheres. I. Linear polarization
Chung, C T Y
2010-01-01
Polarimetric studies of pulsar radio emission traditionally concentrate on how the Stokes vector (I, Q, U, V) varies with pulse longitude, with special emphasis on the position angle (PA) swing of the linearly polarized component. The interpretation of the PA swing in terms of the rotating vector model is limited by the assumption of an axisymmetric magnetic field and the degeneracy of the output with respect to the orientation and magnetic geometry of the pulsar; different combinations of the latter two properties can produce similar PA swings. This paper introduces Stokes phase portraits as a supplementary diagnostic tool with which the orientation and magnetic geometry can be inferred more accurately. The Stokes phase portraits feature unique patterns in the I-Q, I-U, and Q-U planes, whose shapes depend sensitively on the magnetic geometry, inclination angle, beam and polarization patterns, and emission altitude. We construct look-up tables of Stokes phase portraits and PA swings for pure and current-modif...
Sharp Interface Limit for a Stokes/Allen-Cahn System
Abels, Helmut
2016-01-01
We consider the sharp interface limit of a coupled Stokes/Allen-Cahn system, when a parameter $\\varepsilon>0$ that is proportional to the thickness of the diffuse interface tends to zero, in a two dimensional bounded domain. For sufficiently small times we prove convergence of the solutions of the Stokes/Allen-Cahn system to solutions of a sharp interface model, where the interface evolution is given by the mean curvature equation with an additional convection term coupled to a two-phase Stokes system with an additional contribution to the stress tensor, which describes the capillary stress. To this end we construct a suitable approximation of the solution of the Stokes/Allen-Cahn system, using three levels of the terms in the formally matched asymptotic calculations, and estimate the difference with the aid of a suitable refinement of a spectral estimate due to Chen for the linearized Allen-Cahn operator. Moreover, a careful treatment of the coupling terms is needed.
Product integral formalism and non-Abelian Stokes theorem
Energy Technology Data Exchange (ETDEWEB)
Karp, R.L.; Mansouri, F. [Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221 (United States); Rno, J.S. [Department of Physics, University of Cincinnati-RWC, Cincinnati, Ohio 45236 (United States)
1999-11-01
We make use of the properties of product integrals to obtain a surface product integral representation for the Wilson loop operator. The result can be interpreted as the non-Abelian version of Stokes{close_quote} theorem. {copyright} {ital 1999 American Institute of Physics.}
Supersymmetric Wilson Loops and Super Non-Abelian Stokes Theorem
Karp, R L; Karp, Robert L.; Mansouri, Freydoon
2000-01-01
We generalize the standard product integral formalism to incorporateGrassmann valued matrices and show that the resulting supersymmetric productintegrals provide a natural framework for describing supersymmetric Wilsonlines and Wilson loops. We use this formalism to establish the supersymmetricversion of the non-Abelian Stokes Theorem.
Algorithmic Enhancements for the VULCAN Navier-Stokes Solver
Edwards, Jack R.
2004-01-01
Work performed over the last three years has resulted in the addition of several new algorithms to the VULCAN code, NASA's standard for Navier-Stokes calculations in high-speed aeropropulsion devices. This final report describes the new techniques in brief and presents sample results from their use.
Fluxtube model atmospheres and Stokes V zero-crossing wavelengths
Rubio, L R B; Collados, M
1997-01-01
First results of the inversion of Stokes I and V profiles from plage regions near disk center are presented. Both low and high spatial resolution spectra of FeI 6301.5 and FeI 6302.5 A obtained with the Advanced Stokes Polarimeter (ASP) have been considered for analysis. The thin flux tube approximation, implemented in an LTE inversion code based on response functions, is used to describe unresolved magnetic elements. The code allows the simultaneous and consistent inference of all atmospheric quantities determining the radiative transfer with the sole assumption of hydrostatic equilibrium. By considering velocity gradients within the tubes we are able to match the full ASP Stokes profiles. The magnetic atmospheres derived from the inversion are characterized by the absence of significant motions in high layers and strong velocity gradients in deeper layers. These are essential to reproduce the asymmetries of the observed profiles. Our scenario predicts a shift of the Stokes V zero-crossing wavelengths which ...
The Navier-Stokes Equations Theory and Numerical Methods
Masuda, Kyûya; Rautmann, Reimund; Solonnikov, Vsevolod
1990-01-01
These proceedings contain original (refereed) research articles by specialists from many countries, on a wide variety of aspects of Navier-Stokes equations. Additionally, 2 survey articles intended for a general readership are included: one surveys the present state of the subject via open problems, and the other deals with the interplay between theory and numerical analysis.
The Stokes-Einstein relation at moderate Schmidt number.
Balboa Usabiaga, Florencio; Xie, Xiaoyi; Delgado-Buscalioni, Rafael; Donev, Aleksandar
2013-12-07
The Stokes-Einstein relation for the self-diffusion coefficient of a spherical particle suspended in an incompressible fluid is an asymptotic result in the limit of large Schmidt number, that is, when momentum diffuses much faster than the particle. When the Schmidt number is moderate, which happens in most particle methods for hydrodynamics, deviations from the Stokes-Einstein prediction are expected. We study these corrections computationally using a recently developed minimally resolved method for coupling particles to an incompressible fluctuating fluid in both two and three dimensions. We find that for moderate Schmidt numbers the diffusion coefficient is reduced relative to the Stokes-Einstein prediction by an amount inversely proportional to the Schmidt number in both two and three dimensions. We find, however, that the Einstein formula is obeyed at all Schmidt numbers, consistent with linear response theory. The mismatch arises because thermal fluctuations affect the drag coefficient for a particle due to the nonlinear nature of the fluid-particle coupling. The numerical data are in good agreement with an approximate self-consistent theory, which can be used to estimate finite-Schmidt number corrections in a variety of methods. Our results indicate that the corrections to the Stokes-Einstein formula come primarily from the fact that the particle itself diffuses together with the momentum. Our study separates effects coming from corrections to no-slip hydrodynamics from those of finite separation of time scales, allowing for a better understanding of widely observed deviations from the Stokes-Einstein prediction in particle methods such as molecular dynamics.
Well-Posed Stokes/Brinkman and Stokes/Darcy Problems for Coupled Fluid-Porous Viscous Flows
Angot, Philippe
2010-09-01
We present a well-posed model for the Stokes/Brinkman problem with a family of jump embedded boundary conditions (J.E.B.C.) on an immersed interface with weak regularity assumptions. It is issued from a general framework recently proposed for fictitious domain problems. Our model is based on algebraic transmission conditions combining the stress and velocity jumps on the interface Σ separating the fluid and porous domains. These conditions, well chosen to get the coercivity of the operator, are sufficiently general to get the usual immersed boundary conditions on Σ when fictitious domain methods are concerned: Stefan-like, Robin (Fourier), Neumann or Dirichlet… Moreover, the general framework allows to prove the global solvability of some models with physically relevant stress or velocity jump boundary conditions for the momentum transport at a fluid-porous interface. The Stokes/Brinkman problem with Ochoa-Tapia & Whitaker (1995) interface conditions and the Stokes/Darcy problem with Beavers & Joseph (1967) conditions are both proved to be well-posed by an asymptotic analysis. Up to our knowledge, only the Stokes/Darcy problem with Saffman (1971) approximate interface conditions was known to be well-posed.
Institute of Scientific and Technical Information of China (English)
DUAN Huoyuan; LIANG Guoping
2001-01-01
Following Part I., we study the stabilized finite element method for the incom pressible Navier-Stokes equations. It is shown that this new methodology is stable and has an optimal error estimates for all mesh Peclet number, allowing any combination of velocity and pressure interpolation.
Picosecond anti-Stokes generation in a photonic-crystal fiber for interferometric CARS microscopy
DEFF Research Database (Denmark)
Andresen, Esben Ravn
2006-01-01
We generate tunable picosecond anti-Stokes pulses by four-wave mixing of two picosecond pump and Stokes pulse trains in a photonic-crystal fiber. The visible, spectrally narrow anti-Stokes pulses with shifts over 150 nm are generated without generating other spectral features. As a demonstration...
IL “LUMBARD” A SAINT LOUIS. STORIA DI UN’EMIGRAZIONE LINGUISTICA
Directory of Open Access Journals (Sweden)
Chris Stephens
2017-03-01
Full Text Available Nel presente contributo si illustrano i primi dati di un’indagine, tuttora in corso, sullo stato del dialetto dell’Alto Milanese, il Lumbard, nella comunità italoamericana di Saint Louis (Missouri. Avvalendosi degli strumenti tipici dell’indagine sociolinguistica, quali questionari e conversazioni semi-strutturate, e avendo sempre come riferimento la letteratura specialistica e la storia particolare della suddetta comunità, i ricercatori mostrano e spiegano le cause del processo di language shift iniziato tra seconda e terza generazione. Focalizzano quindi la loro attenzione su quale e quanto Lumbard si sia conservato fino ad oggi, dando vita a una raccolta di lemmi e modi di dire riconducibili a cinque grandi aree tematiche: casa, comandi, tempo atmosferico, espressioni colorite e volgari, espressioni familiari. Tale raccolta dimostra come il Lumbard sia una scelta quasi obbligata in determinati domini e contesti e soprattutto come questo dialetto veicoli una chiara e precisa identità, che non è né italiana né americana ma autenticamente lombarda. “Lumbard” in Saint Louis: a story of linguistic emigration This article describes the first results of an investigation, still in progress, into the status of the Alto Milanese dialect, the Lumbard, in the Italian-American community of Saint Louis (Missouri. Utilizing questionnaires and semi-structured conversations typical to sociolinguistics surveys, sociolinguistics literature and reference to the particular history of this community, the researchers demonstrate and explain the causes of the process of language shift that begins between the second and third generations. They then focus attention on which and how much Lumbard remains preserved to this day, identifying a collection of terms and sayings grouped into five broad areas: home, commands, weather, colorful/vulgar expressions and colloquial expressions. This collection reveals how Lumbard is a nearly necessary linguistic
Louis Pasteur: a controversial figure in a debate on scientific ethics.
Ligon, B Lee
2002-04-01
Louis Pasteur long has been heralded as the "father of modern hygiene, public health and much of modern medicine," despite early controversies regarding his findings and methodology. A recently published biography, however, has shed new light on both Pasteur's scientific acumen and integrity. Reactions to this portrayal have been mixed. This article provides an overview of Pasteur's life and the debate regarding his scientific discoveries and honesty that has ensued for more than 100 years, with insights gained from both supporters and critics of the new biography by Gerald L. Geison.
Jaques-Louis Reverdin (1842-1929): the surgeon and the needle.
Fariña-Pérez, Luis A
2010-05-01
With the development and rise of abdominal laparoscopic techniques, the old Reverdin needle has had a revival, because it proved to be useful for the endoscopic closure of laparoscopic access ports, in order to lower the incidence of incisional hernias. Several new modifications of the Reverdin needle, with different names, are in the market now. This new use of an old instrument, prompted a review of the life and work of Jaques-Louis Reverdin, the Swiss surgeon trained in Paris and founder of the modern Swiss surgery. Biographical and bibliographical review of Jaques-MLouis Reverdin and his contributions to surgery Jaques-Louis Reverdin (1842-1929), born in Geneva, completed his medical studies in Paris, where he practised in several well-known hospitals such as La Pitié (with Goselin), Saint Louis (with Guérin), Lariboisiére, and Necker (with Guyon). In 1869 he published and presented in several meetings, a pioneering experience of successful free skin graft procedure, that is still performed in some cases and constitutes the first organ transplantation. In 1870 he presented his doctoral thesis "Etude sur l'uréthrotomie interne" with the expeience of his master Guyon (63 operations), gaining the Civiale prize and the bronze medal of the Paris Faculty of Medicine. He returned back to Geneva in 1872 to begin a long surgical practice and Faculty teaching, and he made seminal contributions to the knowledge of thyroid diseases, in particular on the clinical presentation of function deficiency following exeresis of the thyroid gland ( postoperative myxoedema). His contributions paralleled that made by Theodor Kocher in Bern, the surgeon that received in solitary the Nobel prize for these studies in 1909. With Jean6hyphen;Louis Prevost and Constant Picot, they founded the "Revue medicale de la Suisse romande", the most important Swiss medical journal of the 20th century. He is remembered in the field of Urology for a special needle designed to pass through a suture
Institute of Scientific and Technical Information of China (English)
张龙; 阎晨
2008-01-01
以精致、品质、舒适形成"旅行哲学"并以此作为设计出发点,路易·威登(Louis Vuitton)这个名字现已传遍世界,成为旅行用品最精致的象征。而日本最新艺术偶像村上隆(Takashi Murakami)的加入,为路易·威登注入了新的时尚元素,点燃了又一把流行旺火。
Boundary Layer Structure and Its Relation to Precipitation Over the St. Louis Area.
1980-10-01
rainfall information. - ---------------------- 12 B3 Correlation coefficients between rainfall and divergence. -- 20 C1 Cell and convergence strengths...isotachs and streamlines, temperature, divergence, and rainfall for 0045-0130 CST. St. Louis Arch identified by black dot. -123- AA Bi L~ C1 ST E qLINES AN... nIF S 5 a 1 II B Figure I10. Vertical velocity maps (cm sec-1 ) for 1300 CST. 250 A, 1400 CST 350 1 400CSiT - ~ ~~~ ----- -- -;-- -- II A, Figure
Assessment of ground-water contamination by coal-tar derivatives, St. Louis Park area, Minnesota
Hult, M.F.
1984-01-01
Operation of a coal-tar distillation and wood-preserving facility in St. Louis Park, Minnesota, during 1918-72 contaminated ground water with coal-tar derivatives and inorganic chemicals. Coal-tar derivatives entered the groundwater system through three major paths: (1) Spills and drippings that percolated to the water table, (2) surface runoff and plant process water that was discharged to wetlands south of the former plant site, and (3) movement of coal tar directly into bedrock aquifers through a multiaquifer well on the site.
In Spring 2011, 200 adult white sucker were collected in four areas of the St. Louis River Area of Concern (AOC), located in Minnesota and Wisconsin, USA. The areas included the upper AOC as a reference area, the upper estuary, St. Louis Bay and Superior Bay. Grossly visible abno...
Raman amplification of Stokes pulse in ultra-small silicon on-insulator optical waveguide
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
The stimulated Raman amplification of picosecond Stokes pulse is numerically investigated in ultra-small silicon-oninsulator optical waveguide. Numerical results show that we obtain the gain of up to 30-dB for weak Stokes pulse in the copropagation configuration for 10 mm Jength waveguide using high intensity pump optical pulse. The peak gain, pulse width, rise time, and fall time of Stokes pulse will experience the variation course of decaying then increasing with increasing waveguide length. The time delay of output Stokes pulse is controlled by adjusting the initial time delay of both pump and Stokes pulses.
On Approximation and Computation of Navier-Stokes Flow
Institute of Scientific and Technical Information of China (English)
VARNHORN Werner; ZANGER Florian
2013-01-01
We present an approximation method for the non-stationary nonlinear incompressible Navier-Stokes equations in a cylindrical domain (0,T)×G,where G （C） IR3is a smoothly bounded domain.Our method is applicable to general three-dimensional flow without any symmetry restrictions and relies on existence,uniqueness and representation results from mathematical fluid dynamics.After a suitable time delay in the nonlinear convective term v·▽v we obtain globally (in time) uniquely solvable equations,which-by using semi-implicit time differences-can be transformed into a finite number of Stokes-type boundary value problems.For the latter a boundary element method based on a corresponding hydrodynamical potential theory is carried out.The method is reported in short outlines ranging from approximation theory up to numerical test calculations.
Analysis of one assumption of the Navier-Stokes equations
Budarin, V A
2013-01-01
This article analyses the assumptions regarding the influence of pressure forces during the calculation of the motion of a Newtonian fluid. The purpose of the analysis is to determine the reasonableness of the assumptions and their impact on the results of the analytical calculation. The connections between equations, causes of discrepancies in exact solutions of the Navier-Stokes equations at low Reynolds numbers and the emergence of unstable solutions using computer programs are also addressed. The necessity to complement the well-known equations of motion in mechanical stress requires other equations are substantive. It is shown that there are three methods of solving such a problem and the requirements for the unknown equations are described. Keywords: Navier-Stokes, approximate equation, closing equations, holonomic system.
A fast Stokes inversion technique based on quadratic regression
Teng, Fei; Deng, Yuan-Yong
2016-05-01
Stokes inversion calculation is a key process in resolving polarization information on radiation from the Sun and obtaining the associated vector magnetic fields. Even in the cases of simple local thermodynamic equilibrium (LTE) and where the Milne-Eddington approximation is valid, the inversion problem may not be easy to solve. The initial values for the iterations are important in handling the case with multiple minima. In this paper, we develop a fast inversion technique without iterations. The time taken for computation is only 1/100 the time that the iterative algorithm takes. In addition, it can provide available initial values even in cases with lower spectral resolutions. This strategy is useful for a filter-type Stokes spectrograph, such as SDO/HMI and the developed two-dimensional real-time spectrograph (2DS).
Boussinesq approximation of the Cahn-Hilliard-Navier-Stokes equations
Vorobev, Anatoliy
2010-01-01
We study the interactions between the thermodynamic transition and hydrodynamic flows which would characterise a thermo- and hydro-dynamic evolution of a binary mixture in a dissolution/nucleation process. The primary attention is given to the slow dissolution dynamics. The Cahn-Hilliard approach is used to model the behaviour of evolving and diffusing interfaces. An important peculiarity of the full Cahn-Hilliard-Navier-Stokes equations is the use of the full continuity equation required even for a binary mixture of incompressible liquids, firstly, due to dependence of mixture density on concentration and, secondly, due to strong concentration gradients at liquids' interfaces. Using the multiple-scale method we separate the physical processes occurring on different time scales and, ultimately, provide a strict derivation of the Boussinesq approximation for the Cahn-Hilliard-Navier-Stokes equations. This approximation forms a universal theoretical model that can be further employed for a thermo/hydro-dynamic ...
A Stokes drift approximation based on the Phillips spectrum
Breivik, Øyvind; Janssen, Peter A E M
2016-01-01
A new approximation to the Stokes drift velocity pro?le based on the exact solution for the Phillips spectrum is explored. The pro?file is compared with the monochromatic pro?file and the recently proposed exponential integral profi?le. ERA-Interim spectra and spectra from a wave buoy in the central North Sea are used to investigate the behaviour of the profi?le. It is found that the new profi?le has a much stronger gradient near the surface and lower normalized deviation from the pro?le computed from the spectra. Based on estimates from two open-ocean locations, an average value has been estimated for a key parameter of the profi?le. Given this parameter, the profi?le can be computed from the same two parameters as the monochromatic profi?le, namely the transport and the surface Stokes drift velocity.
Plasmonic metagratings for simultaneous determination of Stokes parameters
Pors, Anders; Bozhevolnyi, Sergey I
2016-01-01
Measuring light's state of polarization is an inherently difficult problem, since the phase information between orthogonal polarization states is typically lost in the detection process. In this work, we bring to the fore the equivalence between normalized Stokes parameters and diffraction contrasts in appropriately designed phase-gradient birefringent metasurfaces and introduce a concept of all-polarization birefringent metagratings. The metagrating, which consists of three interweaved metasurfaces, allows one to easily analyze an arbitrary state of light polarization by conducting simultaneous (i.e., parallel) measurements of the correspondent diffraction intensities that reveal immediately the Stokes parameters of the polarization state under examination. Based on plasmonic metasurfaces operating in reflection at the wavelength of 800 nm, we design and realize phase-gradient birefringent metasurfaces and the correspondent metagrating, while experimental characterization of the fabricated components convinc...
Stokes-vector and Mueller-matrix polarimetry [Invited].
Azzam, R M A
2016-07-01
This paper reviews the current status of instruments for measuring the full 4×1 Stokes vector S, which describes the state of polarization (SOP) of totally or partially polarized light, and the 4×4 Mueller matrix M, which determines how the SOP is transformed as light interacts with a material sample or an optical element or system. The principle of operation of each instrument is briefly explained by using the Stokes-Mueller calculus. The development of fast, automated, imaging, and spectroscopic instruments over the last 50 years has greatly expanded the range of applications of optical polarimetry and ellipsometry in almost every branch of science and technology. Current challenges and future directions of this important branch of optics are also discussed.
Wavelength-Diverse Polarization Modulators for Stokes Polarimetry
Tomczyk, Steven; de Wijn, Alfred G; Nelson, Peter G
2010-01-01
Information about the three-dimensional structure of solar magnetic fields is encoded in the polarized spectra of solar radiation by a host of physical processes. To extract this information, solar spectra must be obtained in a variety of magnetically sensitive spectral lines at high spatial, spectral, and temporal resolution with high precision. The need to observe many different spectral lines drives the development of Stokes polarimeters with a high degree of wavelength diversity. We present a new paradigm for the design of polarization modulators that operate over a wide wavelength range with near optimal polarimetric efficiency and are directly applicable to the next generation of multi-line Stokes polarimeters. These modulators are not achromatic in the usual sense because their polarimetric properties vary with wavelength, but they do so in an optimal way. Thus we refer to these modulators as polychromatic. We present here the theory behind polychromatic modulators, illustrate the concept with design e...
An elastic two-sphere swimmer in Stokes flow
Nasouri, Babak; Elfring, Gwynn J
2016-01-01
Swimming at low Reynolds number in Newtonian fluids is only possible through non-reciprocal body deformations due to the kinematic reversibility of the Stokes equations. We consider here a model swimmer consisting of two linked spheres, wherein one sphere is rigid and the other an incompressible neo-Hookean solid. The two spheres are connected by a rod which changes its length periodically. We show that the deformations of the body are non-reciprocal despite the reversible actuation and hence, the elastic two-sphere swimmer propels forward. Our results indicate that even weak elastic deformations of a body can qualitatively alter swimming dynamics and should not be neglected in analyzing swimming in Stokes flows.
An elastic two-sphere swimmer in Stokes flow
Nasouri, Babak; Elfring, Gwynn
2016-11-01
Swimming at low Reynolds number in Newtonian fluids is only possible through non-reciprocal body deformations due to the kinematic reversibility of the Stokes equations. We consider here a model swimmer consisting of two linked spheres, wherein one sphere is rigid and the other an incompressible neo-Hookean solid. The two spheres are connected by a rod which changes its length periodically. We show that the deformations of the body are non-reciprocal despite the reversible actuation and hence, the elastic two-sphere swimmer propels forward. Our results indicate that even weak elastic deformations of a body can qualitatively alter swimming dynamics and should not be neglected in analyzing swimming in Stokes flows.
Quantum statistics of Raman scattering model with Stokes mode generation
Tanatar, Bilal; Shumovsky, Alexander S.
1994-01-01
The model describing three coupled quantum oscillators with decay of Rayleigh mode into the Stokes and vibration (phonon) modes is examined. Due to the Manley-Rowe relations the problem of exact eigenvalues and eigenstates is reduced to the calculation of new orthogonal polynomials defined both by the difference and differential equations. The quantum statistical properties are examined in the case when initially: the Stokes mode is in the vacuum state; the Rayleigh mode is in the number state; and the vibration mode is in the number of or squeezed states. The collapses and revivals are obtained for different initial conditions as well as the change in time the sub-Poisson distribution by the super-Poisson distribution and vice versa.
Understanding Instrumental Stokes Leakage in Murchison Widefield Array Polarimetry
Sutinjo, Adrian; Lenc, Emil; Wayth, Randall B; Padhi, Shantanu; Hall, Peter; Tingay, Steven J
2014-01-01
This paper offers an electromagnetic, more specifically array theory, perspective on understanding strong instrumental polarization effects for planar low-frequency "aperture arrays" with the Murchison Widefield Array (MWA) as an example. A long-standing issue that has been seen here is significant instrumental Stokes leakage after calibration, particularly in Stokes Q at high frequencies. A simple model that accounts for inter-element mutual coupling is presented which explains the prominence of Q leakage seen when the array is scanned away from zenith in the principal planes. On these planes, the model predicts current imbalance in the X (E-W) and Y (N-S) dipoles and hence the Q leakage. Although helpful in concept, we find that this model is inadequate to explain the full details of the observation data. This finding motivates further experimentation with more rigorous models that account for both mutual coupling and embedded element patterns. Two more rigorous models are discussed: the "full" and "average...
Cascaded forward Brillouin scattering to all Stokes orders
Wolff, Christian; Eggleton, Benjamin J; Steel, Michael J; Poulton, Christopher G
2016-01-01
Inelastic scattering processes such as Brillouin scattering can often function in cascaded regimes and this is likely to occur in certain integrated opto-acoustic devices. We develop a Hamiltonian formalism for cascaded Brillouin scattering valid for both quantum and classical regimes. By regarding Brillouin scattering as the interaction of a single acoustic envelope and a single optical envelope that covers all Stokes and anti-Stokes orders, we obtain a compact model that is well suited for numerical implementation, extension to include other optical nonlinearities or short pulses, and application in the quantum-optics domain. We then theoretically analyze intra-mode forward Brillouin scattering (FBS) for arbitrary waveguides with and without optical dispersion. In the absence of optical dispersion, we find an exact analytical solution. With a perturbative approach, we furthermore solve the case of weak optical dispersion. Our work leads to several key results on intra-mode FBS. For negligible dispersion, we...
Topology optimization of 3D Stokes flow problems
DEFF Research Database (Denmark)
Gersborg-Hansen, Allan
to different flow problems. However, this research has focused on 2D fluid modelling, which limits the practical impact of the computed designs. The explanation of the limitation is that the finite size domain used in topology optimization problems ensures that the velocity components couples, even for Stokes...... flow [3]. Furthermore, it is questionable if such a coupling can be captured by a 2D model especially in non-trivial geometries as typically seen in topology design. This statement is widely accepted in the fluid mechanics community, i.e. that planar fluid models are useful for academic test problems...... fundamental aspects of the topology optimization method applied to the Stokes equations as described below. This work consists of two parts. The main part elaborates on effects caused by 3D fluid modelling on the design. Numerical examples are shown where the design is planar - relevant to micro fluidic...
Benzothiadiazole oligoene fatty acids: fluorescent dyes with large Stokes shifts
Directory of Open Access Journals (Sweden)
Lukas J. Patalag
2016-12-01
Full Text Available Herein, we report on the synthesis and characterization of novel fluorescent fatty acids with large Stokes shifts. Three examples consisting of the same number of carbon atoms and thus of similar chain length are presented differing in their degree of unsaturation. As major fluorogenic contributor at the terminus benzo[c][1,2,5]thiadiazole was used. Respective syntheses based on Wittig reactions followed by iodine-mediated isomerization are presented. The absorption properties are modulated by the number of conjugated C=C double bonds of the oligoene chain ranging from one to three. Large Stokes shifts of about 4900–5700 cm−1 and fluorescence quantum yields of up to 0.44 were observed.
Navier-Stokes predictions of multifunction nozzle flows
Wilmoth, Richard G.; Leavitt, Laurence D.
1987-10-01
A two-dimensional, Navier-Stokes code developed by Imlay based on the implicit, finite-volume method of MacCormack has been applied to the prediction of the flow fields and performance of several nonaxisymmetric, convergent-divergent nozzles with and without thrust vectoring. Comparisons of predictions with experiment show that the Navier-Stokes code can accurately predict both the flow fields and performance for nonaxisymmetric nozzles where the flow is predominantly two-dimensional and at nozzle pressure ratios at or above the design values. Discrepancies between predictions and experiment are noted at lower nozzle pressure ratios where separation typically occurs in portions of the nozzle. The overall trends versus parameters such as nozzle pressure ratio, flap angle, and vector angle were generally predicted correctly.
Polarization ellipse and Stokes parameters in geometric algebra.
Santos, Adler G; Sugon, Quirino M; McNamara, Daniel J
2012-01-01
In this paper, we use geometric algebra to describe the polarization ellipse and Stokes parameters. We show that a solution to Maxwell's equation is a product of a complex basis vector in Jackson and a linear combination of plane wave functions. We convert both the amplitudes and the wave function arguments from complex scalars to complex vectors. This conversion allows us to separate the electric field vector and the imaginary magnetic field vector, because exponentials of imaginary scalars convert vectors to imaginary vectors and vice versa, while exponentials of imaginary vectors only rotate the vector or imaginary vector they are multiplied to. We convert this expression for polarized light into two other representations: the Cartesian representation and the rotated ellipse representation. We compute the conversion relations among the representation parameters and their corresponding Stokes parameters. And finally, we propose a set of geometric relations between the electric and magnetic fields that satisfy an equation similar to the Poincaré sphere equation.
Topology optimization of 3D Stokes flow problems
DEFF Research Database (Denmark)
Gersborg-Hansen, Allan
to different flow problems. However, this research has focused on 2D fluid modelling, which limits the practical impact of the computed designs. The explanation of the limitation is that the finite size domain used in topology optimization problems ensures that the velocity components couples, even for Stokes......Topology optimization has been applied to a multitude of physical systems and is now a mature technology used in industrial practice, see [1] for an overview. Borrvall and Petersson [2] introduced topology optimization of Stokes flow problems which initiated works on extending topology optimization...... flow [3]. Furthermore, it is questionable if such a coupling can be captured by a 2D model especially in non-trivial geometries as typically seen in topology design. This statement is widely accepted in the fluid mechanics community, i.e. that planar fluid models are useful for academic test problems...
Topology optimization of 3D Stokes flow problems
DEFF Research Database (Denmark)
Gersborg-Hansen, Allan; Sigmund, Ole; Bendsøe, Martin P.
is caused by the finite size domain used in topology optimization problems which ensures that the velocity components couples, even for Stokes flow [3]. Physically Stokes flow is an exotic inertia free flow, which in practice complicates mixing by passive devices. Passive mixing devices are relevant......The design of MEMS devices have benefitted from the topology optimization tool and complicated layout problems have been solved, see [1] for an overview. This research is aimed at micro fluidic devices known as micro-Total-Analysis-Systems (muTAS) where the main physical phenomena originate from...... fluid mechanics. In future practice a muTAS could be used by doctors, engineers etc. as a hand held device with short reaction time that provides on-site analysis of a flowing substance such as blood, polluted water or similar. Borrvall and Petersson [2] paved the road for using the topology...
Stokes flow near the contact line of an evaporating drop
Gelderblom, Hanneke; Bloemen, Oscar; Snoeijer, Jacco H.
2011-01-01
The evaporation of sessile drops in quiescent air is usually governed by vapour diffusion. For contact angles below $90^\\circ$, the evaporative flux from the droplet tends to diverge in the vicinity of the contact line. Therefore, the description of the flow inside an evaporating drop has remained a challenge. Here, we focus on the asymptotic behaviour near the pinned contact line, by analytically solving the Stokes equations in a wedge geometry of arbitrary contact angle. The flow field is d...
Time dependent electromagnetic fields and 4-dimensional Stokes' theorem
Andosca, Ryan
2016-01-01
Stokes' theorem is central to many aspects of physics -- electromagnetism, the Aharonov-Bohm effect, and Wilson loops to name a few. However, the pedagogical examples and research work almost exclusively focus on situations where the fields are time-independent so that one need only deal with purely spatial line integrals ({\\it e.g.} $\\oint {\\bf A} \\cdot d{\\bf x}$) and purely spatial area integrals ({\\it e.g.} $\\int (\
Probability density functions of instantaneous Stokes parameters on weak scattering
Chen, Xi; Korotkova, Olga
2017-10-01
The single-point probability density functions (PDF) of the instantaneous Stokes parameters of a polarized plane-wave light field scattered from a three-dimensional, statistically stationary, weak medium with Gaussian statistics and Gaussian correlation function have been studied for the first time. Apart from the scattering geometry the PDF distributions of the scattered light have been related to the illumination's polarization state and the correlation properties of the medium.
ARTICLES: Time-Dependent Stokes Shift from Solvent Dielectric Relaxation
Xu, Jing; Wang, Quan-de; Zhu, Quan; Fu, Ke-xiang; He, Fu-cheng; Li, Xiang-yuan
2010-06-01
The Stokes shift response function, which is related to the time dependent solvation energy, is calculated with the dielectric response function and a novel expression of nonequilibrium solvation energy. In the derivation, relationship between the polarization and the dielectric response function is used. With the dipole-in-a-sphere model applied to the system coumarin 343 and water as the solvent, encouraging agreement with the experimental data from Jimenez et al. is obtained [Nature 369, 471 (1994)].
The Mortar Element Method with Lagrange Multipliers for Stokes Problem
Institute of Scientific and Technical Information of China (English)
Yaqin Jiang
2007-01-01
In this paper, we propose a mortar element method with Lagrange multiplier for incompressible Stokes problem, i.e., the matching constraints of velocity on mortar edges are expressed in terms of Lagrange multipliers. We also present P1 nonconforming element attached to the subdomains. By proving inf-sup condition, we derive optimal error estimates for velocity and pressure. Moreover, we obtain satisfactory approximation for normal derivatives of the velocity across the interfaces.
A New Conserved Energy for Incompressible Navier-Stokes Equations
García-Casado, Manuel
2010-01-01
Pressure conditions in incompressible Navier-Stokes equations give rise to conservation of total energy. The energy rate getting into a volume is the same energy rate that gets out from it. Suitable choice of pressure counteracts energy disipation of viscosity term in such a way that total energy is preserved. As consequence, this prevents kinetic energy blow-up in a given volume of the fluid.
High-order topological asymptotic expansion for Stokes equations
Directory of Open Access Journals (Sweden)
Mohamed Abdelwahed
2016-06-01
Full Text Available We use the topological sensitivity analysis method to solve various optimization problems. It consists of studying the asymptotic expansion of the objective function relative to a perturbation of the domain topology. This expansion becomes insufficient in some applications when it is limited to the first order topological derivative. We present a new topological sensitivity analysis for the Stokes equations based on a high order asymptotic expansion. The derived result is valid for different class of shape functions.
A PARALLEL NONOVERLAPPING DOMAIN DECOMPOSITION METHOD FOR STOKES PROBLEMS
Institute of Scientific and Technical Information of China (English)
Mei-qun Jiang; Pei-liang Dai
2006-01-01
A nonoverlapping domain decomposition iterative procedure is developed and analyzed for generalized Stokes problems and their finite element approximate problems in RN(N=2,3). The method is based on a mixed-type consistency condition with two parameters as a transmission condition together with a derivative-free transmission data updating technique on the artificial interfaces. The method can be applied to a general multi-subdomain decomposition and implemented on parallel machines with local simple communications naturally.
Stabilization of weak solutions to compressible Navier-Stokes equations
Novotný, Anton’ın; Straškraba, Ivan
2000-01-01
In [17] the present authors investigated the stabilization of the weak solutions to space periodic problem for barotropic compressible Navier-Stokes equations. The main goal of this paper is to show the power of the method introduced in [17] by treating other boundary conditions. In fact, the only limitation of the method is potential external force and the validity of the Poincaré inequality for the velocity.
Refinement of Fourier Coefficients from the Stokes Deconvoluted Profile
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
Computer-aided experimental technique was used to study the Stokes deconvolution of X-ray diffraction profile.Considerable difference can be found between the Fourier coefficients obtained from the deconvolutions of singlet and doublet experimental profiles. Nevertheless, the resultant physical profiles corresponding to singlet and doublet profiles are identical. An approach is proposed to refine the Fourier coefficients, and the refined Fourier coefficients coincide well with that obtained from the deconvolution of singlet experimental profile.
Barnoya, Joaquin; Jin, Linda; Hudmon, Karen Suchanek; Schootman, Mario
2015-01-01
To compare availability of nicotine replacement therapy (NRT), tobacco products, and electronic cigarettes (e-cigarettes) in pharmacies in St. Louis, MO. Cross-sectional study, on-site store audits of 322 pharmacies. St. Louis, MO. 242 eligible community pharmacies located in the study area. Pharmacies were visited by trained research assistants who conducted a 5- to 10-minute store audit using a paper-based data collection tool. Availability, accessibility, and pricing of NRT as a function of neighborhood poverty rate and proportion of black residents as well as availability of tobacco products and e-cigarettes. NRT availability decreased as neighborhood poverty rate increased (P = 0.02). Availability without pharmacy personnel assistance also decreased with increasing poverty rate (r = -0.19; 95% CI = -0.06, -0.31) and higher percentage of black residents (r = -0.18; 95% CI = -0.06, -0.31). Prices were lower in neighborhoods with higher poverty rates (P = 0.02) and a higher percentage of black residents (P = 0.03). E-cigarettes were available in 43% of pharmacies, and their availability and price did not differ by poverty rate or percentage of black residents. Low access to NRT might perpetuate smoking disparities in disadvantaged and racially diverse neighborhoods. Study data support policies to ensure equal NRT access to reduce disparities.
Assessing the Bicycle Network in St. Louis: A PlaceBased User-Centered Approach
Directory of Open Access Journals (Sweden)
Bram Boettge
2017-02-01
Full Text Available To transition towards sustainability and increase low-impact transportation, city planners are integrating bicycle infrastructure in urban landscapes. Yet, this infrastructure only promotes cycling according to how well it is sited within a specific city. How to best site bicycle facilities is essential for sustainability planning. We review approaches to assessing and siting new bicycle facilities. Following sustainability science, we argue that active cyclists should be consulted to incorporate users’ site-specific knowledge into bicycle infrastructure assessments. We then pilot an approach that surveys cyclists concerning level of stress along routes ridden in St. Louis, MO, USA. Among the active cyclists surveyed (n = 89, we found stress correlates with speed limit, roadway classification, and number of lanes. Although cyclists surveyed in St. Louis prefer roads with bike lanes over roads with sharrows or no infrastructure, the presence of bicycle infrastructure had no correlation with reported levels of stress. The piloted survey and spatial analytic tool are transferable to other localities. For planners, the maps generated by this participant data approach identify high-stress routes as targets of new infrastructure or information to direct cyclists to safer routes. For bicyclists, the maps generated identify low-stress routes for recreation and commuting.
Heavy metals in urban soils of East St. Louis, IL. Part II: Leaching characteristics and modeling.
Kaminski, M D; Landsberger, S
2000-09-01
The city of East St. Louis, IL, has a history of abundant industrial activities including smelters of ferrous and non-ferrous metals, a coal-fired power plant, companies that produced organic and inorganic chemicals, and petroleum refineries. Following a gross assessment of heavy metals in the community soils (see Part I of this two-part series), leaching tests were performed on specific soils to elucidate heavy metal-associated mineral fractions and general leachability. Leaching experiments, including the Toxicity Characteristic Leaching Procedure (TLCP) and column tests, and sequential extractions, illustrated the low leachability of metals in East St. Louis soils. The column leachate results were modeled using a formulation developed for fly ash leaching. The importance of instantaneous dissolution was evident from the model. By incorporating desorption/adsorption terms into the source term, the model was adapted very well to the time-dependent heavy metal leachate concentrations. The results demonstrate the utility of a simple model to describe heavy metal leaching from contaminated soils.
Campbell, Nancy D
2014-08-01
This article takes up the history of North American psychiatric epidemiology with reference to production of knowledge concerning sociopathic or antisocial personality disorder and drug dependence, abuse, and/or addiction. These overlapping arenas provide a microcosm within which to explore the larger shift of postwar psychiatric epidemiology from community studies based on psychological scales to studies based on specific diagnostic criteria. This paper places the figure of sociologist Lee Nelken Robins within the context of the Department of Psychiatry in the School of Medicine at Washington University in St Louis, Missouri. The St Louis research group--to which Robins was both marginal and central--developed the basis for specific diagnostic criteria and was joined by Robert Spitzer, Jean Endicott and other architects of DSM-III in reorienting American psychiatry towards medical, biological and epidemiological models. Robins was a key linchpin working at the nexus of the psychiatric epidemiological and sociological drug addiction research networks. This article situates her work within the broader set of societal and governmental transformations leading to the technologically sophisticated turn in American psychiatric epidemiology and research on the aetiology of drug abuse and mental health and illness.
An evaluation of public school district tobacco policies in St. Louis County, Missouri.
Barbero, Colleen; Moreland-Russell, Sarah; Bach, Laura E; Cyr, Julianne
2013-08-01
One way to address tobacco use by youth is for primary and secondary schools to adopt and implement comprehensive tobacco policies. The purpose of this study was to evaluate the comprehensiveness of tobacco policies in St. Louis County, Missouri public school districts. We evaluated the strength of tobacco policies from all 23 public school districts located in the county using the Center for Tobacco Policy Research's School Tobacco Policy Index, a standardized tool for rating school tobacco policies. The districts averaged a score of 24.4 of 40 possible points on the Index. Policies scored highest on the Tobacco-Free Environment domain and lowest on the Enforcement domain. Policies averaged about half of the total possible points for the Prevention and Treatment Services and Policy Organization domains. Despite more than a decade of efforts by the Centers for Disease Control and Prevention to improve school tobacco policies, this study shows that policies in St. Louis County districts have yet to meet the standard of comprehensiveness. It is recommended that schools adopt policies that are comprehensive and that address all domains of the School Tobacco Policy Index. © 2013, American School Health Association.
Coupling nonlinear Stokes and Darcy flow using mortar finite elements
Ervin, Vincent J.
2011-11-01
We study a system composed of a nonlinear Stokes flow in one subdomain coupled with a nonlinear porous medium flow in another subdomain. Special attention is paid to the mathematical consequence of the shear-dependent fluid viscosity for the Stokes flow and the velocity-dependent effective viscosity for the Darcy flow. Motivated by the physical setting, we consider the case where only flow rates are specified on the inflow and outflow boundaries in both subdomains. We recast the coupled Stokes-Darcy system as a reduced matching problem on the interface using a mortar space approach. We prove a number of properties of the nonlinear interface operator associated with the reduced problem, which directly yield the existence, uniqueness and regularity of a variational solution to the system. We further propose and analyze a numerical algorithm based on mortar finite elements for the interface problem and conforming finite elements for the subdomain problems. Optimal a priori error estimates are established for the interface and subdomain problems, and a number of compatibility conditions for the finite element spaces used are discussed. Numerical simulations are presented to illustrate the algorithm and to compare two treatments of the defective boundary conditions. © 2010 Published by Elsevier B.V. on behalf of IMACS.
Stellar magnetic fields from four Stokes parameter observations
Rusomarov, N; Piskunov, N
2014-01-01
Magnetic Doppler imaging from four Stokes parameter observations has uncovered a new level of complexity of stellar magnetic fields previously not known. This new information is of interest to the evolution and structure of magnetic fields of intermediate and high-mass stars. Recently, we performed magnetic Doppler imaging study of the chemically peculiar star HD 24712 using phase-resolved spectropolarimetric observations of line-profiles in all four Stokes parameters. The observations were obtained with the HARPSpol instrument on the 3.6-m ESO telescope. Our analysis shows that the magnetic field of HD 24712 has very strong dipolar component with weak small-scale contributions. The finding of dipole-like field for HD 24712 gives evidence for the hypothesis that old Ap stars have predominantly dipolar magnetic fields. We plan on performing magnetic Doppler imaging from four Stokes parameter observations for other Ap/Bp stars as well, which will help us understand the nature of magnetic fields in these stars.
Directory of Open Access Journals (Sweden)
Alexandre Maral
2007-12-01
Full Text Available D’une manière peut‑être plus sensible que partout ailleurs, les objets et les insignes du pouvoir prennent une importance particulière dans le contexte du cérémonial liturgique de la religion catholique. À la chapelle royale de Versailles, la présence régulière du monarque et de sa cour complique encore la situation, d’autant que la desserte est assurée par deux corps distincts d’ecclésiastiques. Dépassant le simple cadre des préséances, Louis XIV a défini autour de sa personne royale un système rituel susceptible d’en manifester le caractère épiscopal dérivé du sacre. De même, l’enjeu juridictionnel représenté par la Chapelle royale se traduit par un jeu subtil d’attitudes, de gestes et de rites, chorégraphie sacrée qui accompagne et exprime les revendications des partisans et des adversaires de l’exemption du lieu de culte royal au regard du diocèse de Paris. Ce discours trouve un écho partiel dans le programme décoratif de la chapelle définitive du palais, achevée en 1710.Objects and symbols of power take on a particular importance in the liturgical ceremony of the Catholic Church, perhaps more so than in any other context. At the royal chapel of Versailles, the regular presence of the king and his court complicated the situation further, all the more so in that religious ceremony was administered by two distinct ecclesiastic bodies. Beyond the rules of precedence, Louis XIV had introduced around his royal persona a system of ritual that would manifest the episcopal identity conferred upon him by his coronation. Similarly, the jurisdictional authority represented by the royal chapel was conveyed in a subtle play of attitudes, gestures and rites, a symbolic choreography that accompanied and expressed the claims of the partisans and adversaries of the exemption of the royal place of worship with regard to the diocese of Paris. This stance was reflected in the decorative scheme of the palace
Second (1178 nm) and third (1242 nm) Stokes Raman fiber lasers without intermediate Stokes cavities
Mejía, E. B.; Juárez-Hernández, M.; De la Cruz-May, L.
2017-07-01
We report and propose a simple Raman fiber laser scheme that generates two or three order Raman Stokes components by using a single strong (unidirectional) cavity formed by a high-reflecting fiber Bragg grating and air-glass interface (fiber output); the intermediate cavities are non-grating, weak and bi-directional cavities that serve as ‘virtual links’ or energy reservoirs. Once the strong cavity reaches operation, it practically consumes (converts) all the energy from pump and intermediate components into a single and clamped (unidirectional) signal. For example, the use of second-Stokes fiber Bragg grating together with glass-air output operated and harvested practically all the energy. Analogously, third Stokes emission was obtained by changing the grating and hence relying on first and second non-grating formed intermediate cavities. The system uses commercial silica fiber and minimizes the use of lossy and costly fiber Bragg gratings. This proposal broadens the possibilities for covering the entire 1000-2000 nm window for applications that use silica fibers.
Saint Louis Regional Library Network, MO.
Included in this set of manuals are: (1) guidelines for document delivery to member libraries within the St. Louis Regional Library Network (SLRLN) in which eligible materials are described, addressing and packing are outlined, routing and deliveries are discussed, and a list of delivery system participants is provided; (2) a descriptive guide to…
Characterizing underwater habitat and other features is difficult and costly, especially in the large St. Louis River Estuary. We are using side-scan sonar (SSS), first developed in the 1960s to remotely sense underwater habitat features from reflected acoustic signals (backscatt...
Saint Louis Regional Library Network, MO.
Included in this set of manuals are: (1) guidelines for document delivery to member libraries within the St. Louis Regional Library Network (SLRLN) in which eligible materials are described, addressing and packing are outlined, routing and deliveries are discussed, and a list of delivery system participants is provided; (2) a descriptive guide to…
Mason, Ted
2011-01-01
The NASA Applied Science & Technology Project Office at Stennis Space Center(SSC) used satellites, in-situ measurements and computational modeling to study relationships between water quality in St. Louis Bay, Mississippi and the watershed characteristics of the Jourdan and Wolf rivers from 2000-2010.
REISEN, WILLIAM K.; Lothrop, Hugh D.; Wheeler, Sarah S.; KENNSINGTON, MARC; Gutierrez, Arturo; Fang, Ying; Garcia, Sandra; LOTHROP, BRANKA
2008-01-01
West Nile virus (family Flaviviridae, genus Flavivirus, WNV) invaded the Colorado Desert biome of southern California during summer 2003 and seemed to displace previously endemic St. Louis encephalitis virus (family Flaviviridae, genus Flavivirus, SLEV, an antigenically similar Flavivirus in the Japanese encephalitis virus serocomplex). Western equine encephalomyelitis virus (family Togaviridae, genus Alphavirus, WEEV), an antigenically distinct Alphavirus, was detected during 2005 and 2006, ...
The St. Louis River Estuary (SLRE) shoreline is ~300 km in length and borders MN and WI from the MN highway 23 downstream to Lake Superior. The shoreline is a complex and diverse mixture of many features from industrial docks and slips in the lower SLRE to complex wetlands and na...
As an invasion prone location, the St. Louis River Estuary (SLRE) has been a case study for ongoing research to develop the framework for a practical Great Lakes monitoring network for early detection of aquatic invasive species (AIS). Early detection, however, necessitates findi...
2011-02-14
... mph project concept, including ] development of an investment-grade business plan and the preparation... Joliet and St. Louis to support additional passenger trains while accommodating the anticipated growth in... Impacts (64 FR 28545; May 26, 1999). The FRA and IDOT will ] use a tiered process, as provided for in...
The Development of the Preverbal Markers in St-Louis-Creole: The Formation of a TMA-System?
Ehrhart, Sabine
1992-01-01
Presents phrases and structures quoted from Melanesian families of the St-Louis tribe in New Caledonia. The system of preverbal markers in Tayo is not well developed and is subject to fluctuation. The use of preverbal markers does not follow the Tempus-Modus-Aspekt rules. (five references) (Author/JP)
Past in vivo and in vitro studies have found estrogenic and aryl hydrocarbon receptor (AhR)-mediated bioactivities associated with final treated effluent from a wastewater treatment plant (WWTP) discharging to the St. Louis River Area of Concern near Duluth, MN, USA. A long-stand...
Solar heating and hot water system installed at Saint Louis, Missouri
1980-01-01
The solar heating and hot water system installed at the William Tao & Associates, Inc., office building in St. Louis, Missouri is described, including maintenance and construction problems, final drawings, system requirements, and manufacturer's component data. The solar system was designed to provide 50 percent of the hot water requirements and 45 percent of the space heating needs for a 900 sq ft office space and drafting room. The solar facility has 252 sq ft of glass tube concentrator collectors and a 1000 gallon steel storage tank buried below a concrete slab floor. Freeze protection is provided by a propylene glycol/water mixture in the collector loop. The collectors are roof mounted on a variable tilt array which is adjusted seasonally and is connected to the solar thermal storage tank by a tube-in-shell heat exchanger. Incoming city water is preheated through the solar energy thermal storage tank.
[A brief philatelic evocation of Louis Pasteur and of his disciples].
Jouzier, E
1997-01-01
Philately is an important source of knowledge on numerous items. Evocation of Louis Pasteur's as well as his disciples life and works throughout stamp collection is a perfect example of this. Born in Dôle in 1822, he spent his youth in Arbois. It is at the Ecole normale supérieure that he performed his work on cristals which led him to establish molecular dissymetry principles. Later, he studied of the fermentation process, he searched the reason of wines' disease and the means to prevent it (i.e. pasteurisation), he solved the problem of the silkworm disease and discovered agents of numerous infectious diseases. He demonstrated scientifically the vaccination principle. In 1885 he tried with success the first human antirabic vaccination. Three years later, the Pasteur Institute was inaugurated. After his death, his works survived in numerous institutes all over the world. Many pasteurians received the Nobel Prize.
Louis Figuier translated in Brazil: science popularizers in the last quarter of 19th century
Directory of Open Access Journals (Sweden)
Kaori Kodama
2017-06-01
Full Text Available This article aims to address aspects of the history of the divulgation of sciences in Brazil in the nineteenth century, through the analysis of the circulation of some translations into Portuguese of the works of French popularizer of science, Louis Figuier. His works, which were translated to different languages, received editions in Brazil and Portugal since late 1860. During this period, a model of popularization of science for non-specialists - working class, women and youth - with emphasis on applied science was gaining terrain. However, this model was also marked by limitations and discontinuities that reflect social issues in the passage to the twentieth century. This paper attempts to highlight the role of translators and editors, understood as mediators of science, whose projects of social reform was primarily focused in popular instruction.
Directory of Open Access Journals (Sweden)
Analía Burgueño
2013-01-01
Full Text Available St. Louis encephalitis virus (SLEV and West Nile virus (WNV belong to the Japanese encephalitis antigenic complex (Flavivirus genus, Flaviviridae family. They show antigenic close relationships and share many similarities in their ecology. Both are responsible for serious human diseases. The aim of this study was to investigate the presence of neutralizing antibodies to these viruses in horses from Uruguay. To do this, 425 horse sera were collected in 2007 and analyzed by plaque reduction neutralization tests. As a result, 205 sera (48.2% were found positive for SLEV, with titers ranging between 10 and 80. Two sera remained inconclusive, since they showed low titers to WNV and SLEV (10 and 20, not allowing us to demonstrate activity of WNV in our territory. This is the first report of circulation of SLEV in horses in Uruguay.
Burgueño, Analía; Spinsanti, Lorena; Díaz, Luis Adrián; Rivarola, María Elisa; Arbiza, Juan; Contigiani, Marta; Delfraro, Adriana
2013-01-01
St. Louis encephalitis virus (SLEV) and West Nile virus (WNV) belong to the Japanese encephalitis antigenic complex (Flavivirus genus, Flaviviridae family). They show antigenic close relationships and share many similarities in their ecology. Both are responsible for serious human diseases. The aim of this study was to investigate the presence of neutralizing antibodies to these viruses in horses from Uruguay. To do this, 425 horse sera were collected in 2007 and analyzed by plaque reduction neutralization tests. As a result, 205 sera (48.2%) were found positive for SLEV, with titers ranging between 10 and 80. Two sera remained inconclusive, since they showed low titers to WNV and SLEV (10 and 20), not allowing us to demonstrate activity of WNV in our territory. This is the first report of circulation of SLEV in horses in Uruguay.
Isolation of saint louis encephalitis virus from a horse with neurological disease in Brazil.
Directory of Open Access Journals (Sweden)
Roberta Rosa
2013-11-01
Full Text Available St. Louis encephalitis virus (SLEV is a causative agent of encephalitis in humans in the Western hemisphere. SLEV is a positive-sense RNA virus that belongs to the Flavivirus genus, which includes West Nile encephalitis virus, Japanese encephalitis virus, Dengue virus and other medically important viruses. Recently, we isolated a SLEV strain from the brain of a horse with neurological signs in the countryside of Minas Gerais, Brazil. The SLEV isolation was confirmed by reverse-transcription RT-PCR and sequencing of the E protein gene. Virus identity was also confirmed by indirect immunofluorescence using commercial antibodies against SLEV. To characterize this newly isolated strain in vivo, serial passages in newborn mice were performed and led to hemorrhagic manifestations associated with recruitment of inflammatory cells into the central nervous system of newborns. In summary this is the first isolation of SLEV from a horse with neurological signs in Brazil.
Huizinga, Richard J.
2011-01-01
Bathymetric surveys were conducted by the U.S. Geological Survey, in cooperation with the Missouri Department of Transportation, on the Missouri and Mississippi Rivers in the vicinity of 12 bridges at 7 highway crossings near St. Louis, Missouri, in October 2010. A multibeam echo sounder mapping system was used to obtain channel-bed elevations for river reaches ranging from 3,280 to 4,590 feet long and extending across the active channel of the Missouri and Mississippi Rivers. These bathymetric scans provide a snapshot of the channel conditions at the time of the surveys and provide characteristics of scour holes that may be useful in the development of predictive guidelines or equations for scour holes. These data also may be used by the Missouri Department of Transportation to assess the bridges for stability and integrity issues with respect to bridge scour.
Pintura y Terror : Jacques-Louis David en 1793-1794
García Hernández, Miguel Ángel
2016-01-01
Entre 1793 y 1794, durante el llamado «Gran Terror», los retratos de los «mártires revolucionarios» de Jacques-Louis David han desarticulado las bases de la pintura de historia al eliminar la narración y el espacio de la perspectiva tal y como habían sido concebidos desde el Renacimiento. Este artículo indaga en este proceso a través del entramado político, social y religioso que se puso en marcha durante la República jacobina. Entre 1793 i 1794, durant l’anomenat «Gran Terror», els retrat...
Louis Gill, George Orwell, de la guerre civile espagnole à 1984
David, Eric
2012-01-01
Publié en 2005, le livre de l’économiste canadien Louis Gill, George Orwell, de la guerre civile espagnole à 1984, a été réédité en 2012. L’auteur a souhaité mettre en lumière, à partir d’une période marquante de la vie d’Eric Arthur Blair (le vrai patronyme d’Orwell), les causes (intellectuelles) qui l’ont conduit à produire des œuvres retentissantes mais pas toujours décryptées à leur juste mesure, notamment quant à leur nature ou leur portée : La Ferme des animaux et 1984. Découpé en cinq ...
Richard Wagner, Louis de Fourcaud, and a Path for French Opera in the 1880s
Directory of Open Access Journals (Sweden)
Marie-Hélène Benoit-Otis
2012-05-01
Full Text Available In a much-quoted interview with Richard Wagner conducted by the French critic Louis de Fourcaud in 1879, and published in different versions in 1880, 1884, and 1886, the composer allegedly advised the French to write operas drawing on their own legendary sources. Contemporary works such as d’Indy’s Fervaal, Chausson’s Le Roi Arthus, and Massenet’s Esclarmonde suggest that Fourcaud’s interview did indeed have a profound impact on the Wagnerian movement in France. However, a close examination of the sources reveals that his text owes much less to Wagner than scholars have previously assumed: in fact, evidence suggests that the most important part of the interview (that is, the advice to French composers was added by Fourcaud himself after Wagner’s death.
Louis-Eugène Varlin e a Comuna de Paris (1871
Directory of Open Access Journals (Sweden)
João Alberto da Costa Pinto
2011-03-01
Full Text Available O artigo propõe uma breve notícia sobre a trajetória política de Louis-Eugène Varlin (1839 - 1871, operário francês (encadernador de livros radicado em Paris (1852 - 1871, intelectual autodidata, um dos principais organizadores da seção francesa da AIT (Associação Internacional dos Trabalhadores a partir de 1865. Personagem emblemático nas lutas sociais acontecidas no período de setembro de 1870 a maio de 1871, quando do cerco à cidade pelas tropas prussianas e depois pelas tropas do governo Thiers, motivos que o levaram à participação no Comitê Central da Guarda Nacional, assim como à organização dos comitês distritais da Comuna (março a maio de 1871.
Solar heating and hot water system installed at St. Louis, Missouri. Final report
Energy Technology Data Exchange (ETDEWEB)
1980-04-01
Information is provided on the solar heating and hot water system installed at the William Tao and Associates, Inc., office building in St. Louis, Missouri. The information consists of description, photos, maintenance and construction problems, final drawing, system requirements and manufacturer's component data. The solar system was designed to provide 50% of the hot water requirements and 45% of the space heating needs for a 900 square foot office space and drafting room. The solar facility has 252 square foot of glass tube concentrator collectors and a 1000 gallon steel storage tank buried below a concrete slab floor. Freeze protection is provided by a propylene glycol/water mixture in the collector loop. The collectors are roof mounted on a variable tilt array which is adjusted seasonally and is connected to the solar thermal storage tank by a tube-in-shell heat exchanger. Incoming city water is preheated through the solar energy thermal storage tank.
Histoire d’un non-objet historiographique : le cas Louis xvi
Directory of Open Access Journals (Sweden)
Aurore Chery
2011-03-01
Full Text Available Bien que la Révolution française ait suscité l’intérêt des chercheurs du monde entier, Louis xvi fait figure de parent pauvre des études universitaires. Même si c’est à son corps défendant, il en est tout de même l’un des principaux protagonistes et la Révolution s’est aussi construite en interrogeant le rôle et la place du roi. Cette situation a eu pour conséquence de conserver vivace la légende dorée que le roi s’est construite en exerçant un contrôle sur son image dès le début de son règne. Elle l’assimile à un nouvel Henri iv, profondément concerné par les maux de ses sujets. Malgré les attaques de la Révolution, cette image continue à exercer une influence considérable sur les biographes de Louis xvi et les historiens de la Révolution.Si la Restauration en a fait un usage sans surprise, elle a, de manière plus étonnante, séduit jusqu’à Jaurès avant de souffrir du discrédit dans lequel sombre le royalisme en choisissant l’antisémitisme au xxe siècle. Néanmoins, c’est aujourd’hui par le détour de l’historiographie anglo-saxonne qu’elle fait sa réapparition et commence seulement à être questionnée.Although the French Revolution has aroused interest of international researchers, Louis xvi is widely neglected by the academic studies. Even if reluctantly, he is yet one of the main protagonists and it is also by questioning the role and the place of the king that the Revolution took its shape.This led to the consequence that the golden legend the king constructed by controlling his image from the beginning of his reign is still very lively today. In it, he is presented as a new Henri iv, deeply concerned by the misfortunes of his subjects. In spite of the attacks of the Revolution, this image still considerably influences Louis xvi’s biographers and the historians of the Revolution.If the Restoration made a not surprising good use of it, it more astonishingly seduced Jaur
Louis Gill, George Orwell, de la guerre civile espagnole à 1984
David, Eric
2012-01-01
Publié en 2005, le livre de l’économiste canadien Louis Gill, George Orwell, de la guerre civile espagnole à 1984, a été réédité en 2012. L’auteur a souhaité mettre en lumière, à partir d’une période marquante de la vie d’Eric Arthur Blair (le vrai patronyme d’Orwell), les causes (intellectuelles) qui l’ont conduit à produire des œuvres retentissantes mais pas toujours décryptées à leur juste mesure, notamment quant à leur nature ou leur portée : La Ferme des animaux et 1984. Découpé en cinq ...
[The "Health system delay" in tuberculosis patients in Saint-Louis Senegal].
Massenet, D; Diop, M; Fall, D; Kante, S; Ndoye, B
2015-08-01
Sixty patients with positive acid fast bacilli sputum smears between were enrolled consecutively between March and August 2012 in the Saint-Louis (Senegal) health district to determine the Health System Delay in response to tuberculosis. The length of time between the first consultation of a TB patient and the start of treatment was, on average, 8.1 days and is among the shortest in the literature. This promptness reduces the risk of infection related to delayed care. This is one of the focuses of the National Programme of Fight against nosocomial infections in Senegal (PRONALIN), as well as the implementation of environmental procedures and the use of masks and respiratory protection equipment.
Louis Jacques Thenard's chemistry courses at the College de France, 1804-1835.
García Belmar, Antonio; Bertomeu-Sánchez, José Ramón
2010-03-01
This article is concerned with the public courses and lecture demonstrations given by Louis Jacques Thenard at the College de France during the first decades of the nineteenth century. The expectations and needs of Thenard's auditors will be studied in order to understand the role played by chemistry courses at the College in the context of the growing and changing Parisian teaching market during the first third of the nineteenth century. The preparation and performance of lecture demonstrations was the main driving force of several major changes in the premises and the personnel associated with the chair of chemistry. Our analysis of the parallel process of expansion and functional differentiation of spaces and personnel will show the multiple interactions taking place between the research and teaching activities developed by Thenard and his team of assistants and students.
Dr Louis T. Wright and the NAACP: pioneers in hospital racial integration.
Reynolds, P P
2000-06-01
Louis Tompkins Wright, the son of a man born into slavery, was an outstanding African American surgeon who devoted his life to the racial integration of health care in the United States. Despite the fact that both his father and stepfather were physicians, despite his innate intellectual gifts and disciplined character, Wright experienced discrimination throughout his life and career. This experience led him to fight for the rights of African Americans, both health care professionals and patients. In addition to making numerous contributions in the fields of surgery and infectious disease, Wright held leadership positions in the National Association for the Advancement of Colored People for more than 20 years, leaving a legacy of equity for African Americans in medical education and in health care.
XVI 'Jacques-Louis Lions' Spanish-French School on Numerical Simulation in Physics and Engineering
Roldán, Teo; Torrens, Juan
2016-01-01
This book presents lecture notes from the XVI ‘Jacques-Louis Lions’ Spanish-French School on Numerical Simulation in Physics and Engineering, held in Pamplona (Navarra, Spain) in September 2014. The subjects covered include: numerical analysis of isogeometric methods, convolution quadrature for wave simulations, mathematical methods in image processing and computer vision, modeling and optimization techniques in food processes, bio-processes and bio-systems, and GPU computing for numerical simulation. The book is highly recommended to graduate students in Engineering or Science who want to focus on numerical simulation, either as a research topic or in the field of industrial applications. It can also benefit senior researchers and technicians working in industry who are interested in the use of state-of-the-art numerical techniques in the fields addressed here. Moreover, the book can be used as a textbook for master courses in Mathematics, Physics, or Engineering.
Louis de brogue: conferencia presentada en el seminario grandes pensadores del fin de milenio
Wolff Isaza, Luis Fernando
1998-01-01
Para comprender mejor el aporte fundamental de Louis De Broglie a la Física Moderna, es necesario repasar sintéticamente el contexto de la Física de finales del siglo XIX y principios del Siglo XX. De manera paradójica, mientras fracasaba la teoría clásica de la Termodinámica para explicar fenómenos como el “Efecto Fotoeléctrico” y la “Radiación del cuerpo negro”, se reconfirmaba la Electrodinámica clásica con la verificación experimental de la velocidad de la luz como invariante, tal como...
Directory of Open Access Journals (Sweden)
Kathleen James-Chakraborty
2014-06-01
Full Text Available Louis Kahn is often credited with having in his National Assembly in Dhaka (1962–1983 introduced modern architecture to Bangladesh. In fact at least as technologically advanced construction as any he employed was already in use there. Nor was he the first to use a sophisticated abstract esthetic in what was from 1947 to 1971 East Pakistan. The importance and originality of the National Assembly instead resides in the care with which he built in reinforced concrete and the forms into which he required that it be cast. These were esthetic decisions rooted in a particular theoretical position; they were located outside established modernist practice of the time in both South Asia and the United States. Indeed operating at such a great remove from home may have heightened Kahn’s authority to implement these forms even as it substantially complicated their execution.
Development of the St. Louis audit of fall risks at residential construction sites.
Kaskutas, Vicki K; Dale, Ann M; Lipscomb, Hester J; Evanoff, Bradley A
2008-01-01
We describe the development and pilot testing of the St. Louis Assessment of Fall Risks, a worksite audit to assess fall prevention safety practices on residential construction sites. Surveillance data and feedback from carpenters and safety instructors regarding work tasks associated with falls from heights were used to develop the audit instrument. The audit focuses on the framing process, including general safety climate/housekeeping, floor joist/sub-floor installation, walking surfaces/edges, wall openings, truss setting, roof sheathing, ladders, scaffolds, and personal fall arrest equipment. The audit was tested at sixteen residential construction sites, documenting excellent inter-rater reliability (kappa = 0.93). Results suggest that the audit has good face and content validity and is a reliable instrument for measuring fall safety risks at residential construction sites. It is practical, easy, and safe to administer, making it a potentially useful instrument for field research as well as regular safety monitoring by foremen and crew.
Isolation of Saint Louis Encephalitis Virus from a Horse with Neurological Disease in Brazil
Rosa, Roberta; Costa, Erica Azevedo; Marques, Rafael Elias; Oliveira, Taismara Simas; Furtini, Ronaldo; Bomfim, Maria Rosa Quaresma; Teixeira, Mauro Martins; Paixão, Tatiane Alves; Santos, Renato Lima
2013-01-01
St. Louis encephalitis virus (SLEV) is a causative agent of encephalitis in humans in the Western hemisphere. SLEV is a positive-sense RNA virus that belongs to the Flavivirus genus, which includes West Nile encephalitis virus, Japanese encephalitis virus, Dengue virus and other medically important viruses. Recently, we isolated a SLEV strain from the brain of a horse with neurological signs in the countryside of Minas Gerais, Brazil. The SLEV isolation was confirmed by reverse-transcription RT-PCR and sequencing of the E protein gene. Virus identity was also confirmed by indirect immunofluorescence using commercial antibodies against SLEV. To characterize this newly isolated strain in vivo, serial passages in newborn mice were performed and led to hemorrhagic manifestations associated with recruitment of inflammatory cells into the central nervous system of newborns. In summary this is the first isolation of SLEV from a horse with neurological signs in Brazil. PMID:24278489
Evaluating the Relative Impact of Monetary and Fiscal Policy in Nigeria using the St. Louis Equation
Directory of Open Access Journals (Sweden)
Michael Adebayo Ajayi
2017-02-01
Full Text Available The controversy existing on the efficacy of monetary and fiscal policy to influence the economy is unending. This study evaluates the relative impact of monetary and fiscal policy in Nigeria from 1986 to 2014 using a modified St. Louis equation. Employing the Ordinary Least Squares estimation method, this study reveals that growth in money supply and export have a positive and significant effect on growth in output of the economy while growth in government expenditure has a negative and insignificant effect. This study provides evidence that monetary policy has a greater growth-stimulating effect on the economy than fiscal policy. It recommends that monetary policy rather than fiscal policy should be relied upon by the Nigerian government as an economic stabilisation tool.
Steady State Stokes Flow Interpolation for Fluid Control
DEFF Research Database (Denmark)
Bhatacharya, Haimasree; Nielsen, Michael Bang; Bridson, Robert
2012-01-01
Fluid control methods often require surface velocities interpolated throughout the interior of a shape to use the velocity as a feedback force or as a boundary condition. Prior methods for interpolation in computer graphics — velocity extrapolation in the normal direction and potential flow...... — suffer from a common problem. They fail to capture the rotational components of the velocity field, although extrapolation in the normal direction does consider the tangential component. We address this problem by casting the interpolation as a steady state Stokes flow. This type of flow captures...... the rotational components and is suitable for controlling liquid animations where tangential motion is pronounced, such as in a breaking wave...
Isogeometric analysis of the isothermal Navier-Stokes-Korteweg equations
Gomez, Hector
2010-05-01
This paper is devoted to the numerical simulation of the Navier-Stokes-Korteweg equations, a phase-field model for water/water-vapor two-phase flows. We develop a numerical formulation based on isogeometric analysis that permits straightforward treatment of the higher-order partial-differential operator that represents capillarity. We introduce a new refinement methodology that desensitizes the numerical solution to the computational mesh and achieves mesh invariant solutions. Finally, we present several numerical examples in two and three dimensions that illustrate the effectiveness and robustness of our approach. © 2010 Elsevier B.V.
INERTIAL ALGORITHMS FOR THE STATIONARY NAVIER-STOKES EQUATIONS
Institute of Scientific and Technical Information of China (English)
Hou Yanren(侯延仁); R.M.M. Mattheij
2003-01-01
Several kind of new numerical schemes for the stationary Navier-Stokes equa-tions based on the virtue of Inertial Manifold and Approximate Inertial Manifold, whichwe call them inertial algorithms in this paper, together with their error estimations are pre-sented. All these algorithms are constructed under an uniform frame, that is to constructsome kind of new projections for the Sobolev space in which the true solution is sought.It is shown that the proposed inertial algorithms can greatly improve the convergence rateof the standard Galerkin approximate solution with lower computing effort. And somenumerical examples are also given to verify results of this paper.
Coherent Anti-Stokes Raman Scattering Heterodyne Interferometry
Bredfeldt, J S; Vinegoni, C; Hambir, S; Boppart, S A
2003-01-01
A new interferometric technique is demonstrated for measuring Coherent Anti-Stokes Raman Scattering (CARS) signals. Two forward-directed CARS signals are generated, one in each arm of an interferometer. The deterministic nature of the CARS process allows for these two signals, when spatially and temporally overlapped, to interfere with one another. Heterodyne detection can therefore be employed to increase the sensitivity in CARS signal detection. In addition, nonlinear CARS interferometry will facilitate the use of this spectroscopic technique for molecular contrast in Optical Coherence Tomography (OCT).
Stokes Flow with Slip and Kuwabara Boundary Conditions
Indian Academy of Sciences (India)
Sunil Datta; Satya Deo
2002-08-01
The forces experienced by randomly and homogeneously distributed parallel circular cylinder or spheres in uniform viscous flow are investigated with slip boundary condition under Stokes approximation using particle-in-cell model technique and the result compared with the no-slip case. The corresponding problem of streaming flow past spheroidal particles departing but little in shape from a sphere is also investigated. The explicit expression for the stream function is obtained to the first order in the small parameter characterizing the deformation. As a particular case of this we considered an oblate spheroid and evaluate the drag on it.
Abelian Chern-Simons theory, Stokes' Theorem, and generalized connections
Sahlmannn, Hanno
2010-01-01
Generalized connections and their calculus have been developed in the context of quantum gravity. Here we apply them to abelian Chern-Simons theory. We derive the expectation values of holonomies in U(1) Chern-Simons theory using Stokes' Theorem, flux operators and generalized connections. A framing of the holonomy loops arises in our construction, and we show how, by choosing natural framings, the resulting expectation values nevertheless define a functional over gauge invariant cylindrical functions. The abelian theory considered in the present article is test case for our method. It can also be applied to the non-abelian theory. Results for that case will be reported elsewhere.
Visualization of synthetic jets at higher Stokes numbers
Directory of Open Access Journals (Sweden)
Trávníček Zdeněk
2012-04-01
Full Text Available Visualization of synthetic jets at higher Stokes numbers (S = 90 and 127 by the phase-locked smoke-wire technique is presented and discussed. The working fluid is air. The Reynolds numbers are quantified using hot-wire anemometry. Although our method of visualization essentially provides only qualitative results, the present study also demonstrates some quantitative results, namely the behavior of the zero-net-mass-flux jet near its critical stage. Visualization of the sub-critical stage is also shown.
3D Topology optimization of Stokes flow problems
DEFF Research Database (Denmark)
Gersborg-Hansen, Allan; Dammann, Bernd
for the fluid behavior in a micro fluidic device. Such a device has finite size and a large degree of freedom for the design of geometry. Physically Stokes flow is an exotic inertia free flow. This, however, complicates mixing by passive devices. Passive devices, that is, devices without moving parts, are often......, the optimizer suggests a design that stretches the hot-cold interface, which is encouraging since "stretching and folding" is known to be key ingredients in efficient mixing. The modelling is performed using a finite element based solver, with analytically derived sensitivities that drives a gradient based...... Program Interface, http://www.openmp.org/...
Topology optimization of mass distribution problems in Stokes flow
DEFF Research Database (Denmark)
Gersborg-Hansen, Allan; Berggren, Martin; Dammann, Bernd
We consider topology optimization of mass distribution problems in 2D and 3D Stokes flow with the aim of designing devices that meet target outflow rates. For the purpose of validation, the designs have been post processed using the image processing tools available in FEMLAB. In turn, this has...... enabled an evaluation of the design with a body fitted mesh in a standard analysis software relevant in engineering practice prior to design manufacturing. This work investigates the proper choice of a maximum penalization value during the optimization process that ensures that the target outflow rates...
Dual Variational Principles for 3-D Navier-Stokes Equations
Liu, G. L.
Just recently the exact variational principles (VP) of the full 3-D Navier-Stokes equations of viscous flow have been successfully established for the first time by the present author by means of a systematic reversed deduction method via the undetermined function. As a continuation and further development of that - a pair of new dual (reciprocal)VP is generated herein by means of the Friedrichs involutory transformation. These VP have the advantage over the previous ones that they possess apparent physical meaning of energy, providing a new rigorous theoretical basis for the finite element analysis of 3-D viscous flow.
A TYPE OF NEW POSTERIORI ERROR ESTIMATORS FOR STOKES PROBLEMS
Institute of Scientific and Technical Information of China (English)
罗振东; 王烈衡; 李雅如
2001-01-01
In this paper, a new discrete formulation and a type of new posteriori error estimators for the second-order element discretization for Stokes problems are presented, where pressure is approximated with piecewise first-degree polynomials and velocity vector field with piecewise seconddegree polynomials with a cubic bubble function to be added. The estimators are the globally upper and locally lower bounds for the error of the finite element discretization. It is shown that the bubble part for this second-order element approximation is substituted for the other parts of the approximate solution.
Discrete Exterior Calculus Discretization of Incompressible Navier-Stokes Equations
Mohamed, Mamdouh S.
2017-05-23
A conservative discretization of incompressible Navier-Stokes equations over surface simplicial meshes is developed using discrete exterior calculus (DEC). Numerical experiments for flows over surfaces reveal a second order accuracy for the developed scheme when using structured-triangular meshes, and first order accuracy otherwise. The mimetic character of many of the DEC operators provides exact conservation of both mass and vorticity, in addition to superior kinetic energy conservation. The employment of barycentric Hodge star allows the discretization to admit arbitrary simplicial meshes. The discretization scheme is presented along with various numerical test cases demonstrating its main characteristics.
Towards an ideal preconditioner for linearized Navier-Stokes problems
Energy Technology Data Exchange (ETDEWEB)
Murphy, M.F. [Univ. of Bristol (United Kingdom)
1996-12-31
Discretizing certain linearizations of the steady-state Navier-Stokes equations gives rise to nonsymmetric linear systems with indefinite symmetric part. We show that for such systems there exists a block diagonal preconditioner which gives convergence in three GMRES steps, independent of the mesh size and viscosity parameter (Reynolds number). While this {open_quotes}ideal{close_quotes} preconditioner is too expensive to be used in practice, it provides a useful insight into the problem. We then consider various approximations to the ideal preconditioner, and describe the eigenvalues of the preconditioned systems. Finally, we compare these preconditioners numerically, and present our conclusions.
Louis Wirth y el individuo promedio: Un salto cualitativo al individuo metropolitano de G. Simmel
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Gino Bailey
2013-07-01
Full Text Available Louis Wirth nunca tuvo el reconocimiento científico e institucional dentro de la sociología, diferenciándolo de sus pares: Park, Burgess, Mckenzie y Small. Su cambio de perspectiva y enfoque al interior de la escuela de Chicago, lo distingu e respecto de sus colegas y lo conecta directamente con la visión de la ciudad que G. Simmel promulgó, abriendo de esta forma una perspectiva crítica que pretendía cuestionar el modo de vida urbano entendido como un modelo de desarrollo de las ciudades. Así, Wirth, identifica las fuerzas que forman la ciudad contemporánea como propias del saber sociológico, dando un paso cualitativo respecto Simmel, al asociar el aislamiento del individuo metropolitano a un modelo de desarrollo urbano particular, basado en la organización económica de las sociedades de masas, que aumenta aún más la coexistencia molecular de individuos que han perdido sus lazos más íntimos de amistad. Abstract Louis Wirth was never awarded in sociology, differentiating it from its peers: Park, Burgess, McKenzie and Small. The change of perspective and focus within the Chicago school, what distinguishes respect of his colleagues and the city approximates G. Simmel thought, placing a critical perspective that sought to understand the urban lifestyle as a model of development of cities. So Wirth, identifies the forces that shape the contemporary city as typical of sociological knowledge, qualitative stepping on Simmel, the isolation of the individual associate a metropolitan urban development model particular, based on the economic organization of mass society , which further increases the molecular coexistence of individuals who have lost their closest ties of friendship.
The proper orthogonal decomposition method for the Navier-Stokes equations
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
The proper orthogonal decomposition (POD) method for the instationary Navier-Stokes equations is considered. Several numerical approaches to evaluating the POD eigenfunctions are presented. The POD eigenfunctions are applied as a basis for a Galerkin projection of the instationary Navier-Stokes equations. And a low-dimensional ordinary differential models for fluid flows governed by the instationary Navier-Stokes equations are constructed. The numerical examples show that the method is feasible and efficien...
A FINITE ELEMENT SOLVER FOR NAVIER-STOKES EQUATIONS VIA VORTICITY AND VELOCITY
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
The incompressible Navier-Stokes equations are solved via variables of vorticity and velocity. Firstly, a rigorous variational framework with the equivalence between the velocity-pressure and the vorticity-velocity formulations is presented in a Lipschitz domain. Next, a class of Galerkin finite element approximations of the corresponding variational form is introduced, and a convergence analysis is given for the Stokes problem. Finally,an iterative finite element solver for the Navier-Stokes problem is proposed.``
On the emergence of the Navier-Stokes-α model for turbulent channel flows
Foias, Ciprian; Tian, Jing; Zhang, Bingsheng
2016-08-01
In a series of papers (see Foias et al. [J. Dyn. Differ. Equations 14(1), 1-35 (2002)] and the pertinent references therein), the 3D Navier-Stokes-α model was shown to be a useful complement to the 3D Navier-Stokes equations, and in particular, to be a good Reynolds version of the latter equations. In this work, we introduce a simple Reynolds averaging which, due to the wall roughness, transforms the Navier-Stokes equations into the Navier-Stokes-α model.
QUASI-NEUTRALLIMIT OF THE BIPOLAR NAVIER-STOKES-POISSON SYSTEM
Institute of Scientific and Technical Information of China (English)
Yang Xiuhui
2011-01-01
This paper is concerned with the quasi-neutral limit of the bipolar NavierStokes-Poisson system.It is rigorously proved,by introducing the new modulated energy functional and using the refined energy analysis,that the strong solutions of the bipolar Navier-Stokes-Poisson system converge to the strong solution of the compressible NavierStokes equations as the Debye length goes to zero.Moreover,if we let the viscous coefficients and the Debye length go to zero simultaneously,then we obtain the convergence of the strong solutions of bipolar Navier-Stokes-Poisson system to the strong solution of the compressible Euler equations.
Stokes Efficiency of Molecular Motor-Cargo Systems
Directory of Open Access Journals (Sweden)
Hongyun Wang
2008-01-01
Full Text Available A molecular motor utilizes chemical free energy to generate a unidirectional motion through the viscous fluid. In many experimental settings and biological settings, a molecular motor is elastically linked to a cargo. The stochastic motion of a molecular motor-cargo system is governed by a set of Langevin equations, each corresponding to an individual chemical occupancy state. The change of chemical occupancy state is modeled by a continuous time discrete space Markov process. The probability density of a motor-cargo system is governed by a two-dimensional Fokker-Planck equation. The operation of a molecular motor is dominated by high viscous friction and large thermal fluctuations from surrounding fluid. The instantaneous velocity of a molecular motor is highly stochastic: the past velocity is quickly damped by the viscous friction and the new velocity is quickly excited by bombardments of surrounding fluid molecules. Thus, the theory for macroscopic motors should not be applied directly to molecular motors without close examination. In particular, a molecular motor behaves differently working against a viscous drag than working against a conservative force. The Stokes efficiency was introduced to measure how efficiently a motor uses chemical free energy to drive against viscous drag. For a motor without cargo, it was proved that the Stokes efficiency is bounded by 100% [H. Wang and G. Oster, (2002]. Here, we present a proof for the general motor-cargo system.
Full-Stokes polychromatic polarimeter design for Arago
Pertenais, Martin; Neiner, Coralie; Petit, Pascal
2016-07-01
The UVMag consortium will propose the Arago space mission to the ESA call Cosmic Vision M5. This mission aims at characterizing all kind of stars and their environment simultaneously, to better understand the cycle of matter in our galaxy. It carries a single instrument, a spectropolarimeter, acquiring data from 119 to 888 nm and enabling the determination of the magnetic field of stars thanks to the Zeeman effect. One of the key instrumental point of this project is the development of an efficient polarimeter over the large spectral range and in space. We chose to use a polychromatic temporal modulation to achieve a measurement of all four Stokes parameters: I the intensity, Q and U the linear polarization states, and V the circular polarization. The modulator is composed by several birefringent Magnesium Fluoride plates, optimized to achromatize the extraction efficiency of the Stokes parameters from the FUV to the NIR. This polarization modulator is followed by a polarization beam-splitter to analyze the state of the light. After the polarization analysis, the light goes through a high-resolution spectrograph. We present the theoretical optimization and design of the polarimeter and of the whole instrument, as well as the first laboratory results on this concept.
Dumbbell formation for elastic capsules in nonlinear extensional Stokes flows
Dimitrakopoulos, P.
2017-06-01
Cross-slot and four-roll-mill microdevices are commonly used for particle manipulation and characterization owing to the stagnation-point flow at the device center. Because of the solid boundaries, these devices may generate extensional Stokes flows where the velocity is a nonlinear function of position associated with a decreased pressure at the particle edges and an increased pressure at the particle middle. Our computational investigation shows that in this class of Stokes flows, an elastic capsule made of a strain-hardening membrane develops two distinct steady-state conformations at strong flows, i.e., an elongated weak dumbbell shape with rounded edges at low flow nonlinearity and a laterally extended dumbbell shape at high flow nonlinearity. These effects are more pronounced for the less strain-hardening capsules which develop a flat extended middle where the two sides of the membrane approach each other. The strong stability properties of the strain-hardening capsules (owing to the development of strong membrane tensions) contrast significantly with the behavior of droplets in these nonlinear flows which are unable to achieve highly deformed steady-state dumbbell shapes owing to their constant surface tension.
Navier–Stokes flow in converging–diverging distensible tubes
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Taha Sochi
2015-09-01
Full Text Available We use a method based on the lubrication approximation in conjunction with a residual-based mass-continuity iterative solution scheme to compute the flow rate and pressure field in distensible converging–diverging tubes for Navier–Stokes fluids. We employ an analytical formula derived from a one-dimensional version of the Navier–Stokes equations to describe the underlying flow model that provides the residual function. This formula correlates the flow rate to the boundary pressures in straight cylindrical elastic tubes with constant-radius. We validate our findings by the convergence toward a final solution with fine discretization as well as by comparison to the Poiseuille-type flow in its convergence toward analytic solutions found earlier in rigid converging–diverging tubes. We also tested the method on limiting special cases of cylindrical elastic tubes with constant-radius where the numerical solutions converged to the expected analytical solutions. The distensible model has also been endorsed by its convergence toward the rigid Poiseuille-type model with increasing the tube wall stiffness. Lubrication-based one-dimensional finite element method was also used for verification. In this investigation five converging–diverging geometries are used for demonstration, validation and as prototypes for modeling converging–diverging geometries in general.
Microscopic statistical description of incompressible Navier-Stokes granular fluids
Tessarotto, Massimo; Mond, Michael; Asci, Claudio
2017-05-01
Based on the recently established Master kinetic equation and related Master constant H-theorem which describe the statistical behavior of the Boltzmann-Sinai classical dynamical system for smooth and hard spherical particles, the problem is posed of determining a microscopic statistical description holding for an incompressible Navier-Stokes fluid. The goal is reached by introducing a suitable mean-field interaction in the Master kinetic equation. The resulting Modified Master Kinetic Equation (MMKE) is proved to warrant at the same time the condition of mass-density incompressibility and the validity of the Navier-Stokes fluid equation. In addition, it is shown that the conservation of the Boltzmann-Shannon entropy can similarly be warranted. Applications to the plane Couette and Poiseuille flows are considered showing that they can be regarded as final decaying states for suitable non-stationary flows. As a result, it is shown that an arbitrary initial stochastic 1-body PDF evolving in time by means of MMKE necessarily exhibits the phenomenon of Decay to Kinetic Equilibrium (DKE), whereby the same 1-body PDF asymptotically relaxes to a stationary and spatially uniform Maxwellian PDF.
Nonstationary Stokes System in Cylindrical Domains Under Boundary Slip Conditions
Zaja¸czkowski, Wojciech M.
2017-03-01
Existence and uniqueness of solutions to the nonstationary Stokes system in a cylindrical domain {Ωsubset{R}^3} and under boundary slip conditions are proved in anisotropic Sobolev spaces. Assuming that the external force belong to {L_r(Ω×(0,T))} and initial velocity to {W_r^{2-2/r}(Ω)} there exists a solution such that velocity belongs to {W_r^{2,1}(Ω×(0,T))} and gradient of pressure to {L_r(Ω×(0,T))}, {rin(1,∞)}, {T > 0}. Thanks to the slip boundary conditions and a partition of unity the Stokes system is transformed to the Poisson equation for pressure and the heat equation for velocity. The existence of solutions to these equations is proved by applying local considerations. In this case we have to consider neighborhoods near the edges which by local mapping can be transformed to dihedral angle {π/2}. Hence solvability of the problem bases on construction local Green functions (near an interior point, near a point of a smooth part of the boundary, near a point of the edge) and their appropriate estimates. The technique presented in this paper can also work in other functional spaces: Sobolev-Slobodetskii, Besov, Nikolskii, Hölder and so on.
Microscopic statistical description of incompressible Navier-Stokes granular fluids
Tessarotto, Massimo; Asci, Claudio
2016-01-01
Based on the recently-established Master kinetic equation and related Master constant H-theorem which describe the statistical behavior of the Boltzmann-Sinai classical dynamical system for smooth and hard spherical particles, the problem is posed of determining a microscopic statistical description holding for an incompressible Navier-Stokes fluid. The goal is reached by introducing a suitable mean-field interaction in the Master kinetic equation. The resulting Modified Master Kinetic Equation (MMKE) is proved to warrant at the same time the condition of mass-density incompressibility and the validity of the Navier-Stokes fluid equation. In addition, it is shown that the conservation of the Boltzmann-Shannon entropy can similarly be warranted. Applications to the plane Couette and Poiseuille flows are considered showing that they can be regarded as final decaying states for suitable non-stationary flows. As a result, it is shown that an arbitrary initial stochastic $1-$body PDF evolving in time by means of M...
Boussinesq approximation of the Cahn-Hilliard-Navier-Stokes equations.
Vorobev, Anatoliy
2010-11-01
We use the Cahn-Hilliard approach to model the slow dissolution dynamics of binary mixtures. An important peculiarity of the Cahn-Hilliard-Navier-Stokes equations is the necessity to use the full continuity equation even for a binary mixture of two incompressible liquids due to dependence of mixture density on concentration. The quasicompressibility of the governing equations brings a short time-scale (quasiacoustic) process that may not affect the slow dynamics but may significantly complicate the numerical treatment. Using the multiple-scale method we separate the physical processes occurring on different time scales and, ultimately, derive the equations with the filtered-out quasiacoustics. The derived equations represent the Boussinesq approximation of the Cahn-Hilliard-Navier-Stokes equations. This approximation can be further employed as a universal theoretical model for an analysis of slow thermodynamic and hydrodynamic evolution of the multiphase systems with strongly evolving and diffusing interfacial boundaries, i.e., for the processes involving dissolution/nucleation, evaporation/condensation, solidification/melting, polymerization, etc.
An optimal iterative solver for the Stokes problem
Energy Technology Data Exchange (ETDEWEB)
Wathen, A. [Univ. of Bristol (United Kingdom); Silvester, D.
1994-12-31
Discretisations of the classical Stokes Problem for slow viscous incompressible flow gives rise to systems of equations in matrix form for the velocity u and the pressure p, where the coefficient matrix is symmetric but necessarily indefinite. The square submatrix A is symmetric and positive definite and represents a discrete (vector) Laplacian and the submatrix C may be the zero matrix or more generally will be symmetric positive semi-definite. For `stabilised` discretisations (C {ne} 0) and descretisations which are inherently `stable` (C = 0) and so do not admit spurious pressure components even as the mesh size, h approaches zero, the Schur compliment of the matrix has spectral condition number independent of h (given also that B is bounded). Here the authors will show how this property together with a multigrid preconditioner only for the Laplacian block A yields an optimal solver for the Stokes problem through use of the Minimum Residual iteration. That is, combining Minimum Residual iteration for the matrix equation with a block preconditioner which comprises a small number of multigrid V-cycles for the Laplacian block A together with a simple diagonal scaling block provides an iterative solution procedure for which the computational work grows only linearly with the problem size.
Modeling Vortex Generators in a Navier-Stokes Code
Dudek, Julianne C.
2011-01-01
A source-term model that simulates the effects of vortex generators was implemented into the Wind-US Navier-Stokes code. The source term added to the Navier-Stokes equations simulates the lift force that would result from a vane-type vortex generator in the flowfield. The implementation is user-friendly, requiring the user to specify only three quantities for each desired vortex generator: the range of grid points over which the force is to be applied and the planform area and angle of incidence of the physical vane. The model behavior was evaluated for subsonic flow in a rectangular duct with a single vane vortex generator, subsonic flow in an S-duct with 22 corotating vortex generators, and supersonic flow in a rectangular duct with a counter-rotating vortex-generator pair. The model was also used to successfully simulate microramps in supersonic flow by treating each microramp as a pair of vanes with opposite angles of incidence. The validation results indicate that the source-term vortex-generator model provides a useful tool for screening vortex-generator configurations and gives comparable results to solutions computed using gridded vanes.
Pressure moderation and effective pressure in Navier-Stokes flows
Tran, Chuong V.; Yu, Xinwei
2016-10-01
We study the Cauchy problem of the Navier-Stokes equations by both semi-analytic and classical energy methods. The former approach provides a physical picture of how viscous effects may or may not be able to suppress singularity development. In the latter approach, we examine the pressure term that drives the dynamics of the velocity norms \\parallel u{{\\parallel}{{Lq}}} , for q≥slant 3 . A key idea behind this investigation is due to the fact that the pressure p in this term is determined up to a function of both space and |u| , say P(x,|u|) , which may assume relatively broad forms. This allows us to use P as a pressure moderator in the evolution equation for \\parallel u{{\\parallel}{{Lq}}} , whereby optimal regularity criteria can be sought by varying P within its admissible classes. New regularity criteria are derived with and without making use of the moderator. The results obtained in the absence of the moderator feature some improvement over existing criteria in the literature. Several criteria are derived in terms of the moderated (effective) pressure p+P . A simple moderation scheme and the plausibility of the present approach to the problem of Navier-Stokes regularity are discussed.
The effect of collision, Stokes and Reynolds numbers on turbophoresis
Esmaily-Moghadam, Mahdi; Mani, Ali
2016-11-01
Migration of inertial particles toward solid boundaries in turbulent flows is known as turbophoresis. In this study, we investigate the effect of various parameters on turbophoresis through direct numerical simulations of turbulent flow laden with Lagrangian point-particles. We consider a flow of air in a square duct at a bulk Reynolds number of 5,000 to 20,000 dispersed with nickel particles ranging in size from 4 to 16 micron in diameter. We examine the effect of the Stokes and Reynolds numbers on the near-wall particle concentration and its relationship to the turbophoretic velocity. Our results are consistent with the previously published results pertaining to the saturation of the turbophoretic velocity for Stokes numbers larger than 10. Adopting a hard sphere collision model, we examine the role of collisions on the near wall concentration and demonstrate the sensitivity of the results to the restitution coefficient. Our findings show that while reducing the restitution coefficient leads to a higher degree of turbophoresis; collision can decrease the near wall concentration by orders of magnitude for a global particle volume fraction of O (10-5) . This work was supported by the United States Department of Energy under the Predictive Science Academic Alliance Program 2 (PSAAP2) at Stanford University.
Algorithmic Enhancements to the VULCAN Navier-Stokes Solver
Litton, D. K.; Edwards, J. R.; White, J. A.
2003-01-01
VULCAN (Viscous Upwind aLgorithm for Complex flow ANalysis) is a cell centered, finite volume code used to solve high speed flows related to hypersonic vehicles. Two algorithms are presented for expanding the range of applications of the current Navier-Stokes solver implemented in VULCAN. The first addition is a highly implicit approach that uses subiterations to enhance block to block connectivity between adjacent subdomains. The addition of this scheme allows more efficient solution of viscous flows on highly-stretched meshes. The second algorithm addresses the shortcomings associated with density-based schemes by the addition of a time-derivative preconditioning strategy. High speed, compressible flows are typically solved with density based schemes, which show a high level of degradation in accuracy and convergence at low Mach numbers (M less than or equal to 0.1). With the addition of preconditioning and associated modifications to the numerical discretization scheme, the eigenvalues will scale with the local velocity, and the above problems will be eliminated. With these additions, VULCAN now has improved convergence behavior for multi-block, highly-stretched meshes and also can solve the Navier-Stokes equations for very low Mach numbers.
Stokes drift for inertial particles transported by water waves
Boffetta, G; Mazzino, A; Onorato, M; Santamaria, F
2012-01-01
We study the effect of surface gravity waves on the motion of inertial particles in an incompressible fluid. Using the multiple-scale technique, we perform an analytical calculation which allows us to predict the dynamics of such particles; results are shown for both the infinite- and finite-depth regimes. Numerical simulations based on the velocity field resulting from the second-order Stokes theory for the surface elevation have been performed, and an excellent agreement with the analytical predictions is observed. Such an agreement seems to hold even beyond the formal applicability of the theory. We find that the presence of inertia leads to a non-negligible correction to the well-known horizontal Stokes drift; moreover, we find that the vertical velocity is also affected by a drift. The latter result may have some relevant consequences on the rate of sedimentation of particles of finite size. We underline that such a drift would also be observed in the (hypothetical) absence of the gravitational force.
Brain cancer probed by native fluorescence and stokes shift spectroscopy
Zhou, Yan; Liu, Cheng-hui; He, Yong; Pu, Yang; Li, Qingbo; Wang, Wei; Alfano, Robert R.
2012-12-01
Optical biopsy spectroscopy was applied to diagnosis human brain cancer in vitro. The spectra of native fluorescence, Stokes shift and excitation spectra were obtained from malignant meningioma, benign, normal meningeal tissues and acoustic neuroma benign tissues. The wide excitation wavelength ranges were used to establish the criterion for distinguishing brain diseases. The alteration of fluorescence spectra between normal and abnormal brain tissues were identified by the characteristic fluorophores under the excitation with UV to visible wavelength range. It was found that the ratios of the peak intensities and peak position in both spectra of fluorescence and Stokes shift may be used to diagnose human brain meninges diseases. The preliminary analysis of fluorescence spectral data from cancer and normal meningeal tissues by basic biochemical component analysis model (BBCA) and Bayes classification model based on statistical methods revealed the changes of components, and classified the difference between cancer and normal human brain meningeal tissues in a predictions accuracy rate is 0.93 in comparison with histopathology and immunohistochemistry reports (gold standard).
An efficient iterative method for the generalized Stokes problem
Energy Technology Data Exchange (ETDEWEB)
Sameh, A. [Univ. of Minnesota, Twin Cities, MN (United States); Sarin, V. [Univ. of Illinois, Urbana, IL (United States)
1996-12-31
This paper presents an efficient iterative scheme for the generalized Stokes problem, which arises frequently in the simulation of time-dependent Navier-Stokes equations for incompressible fluid flow. The general form of the linear system is where A = {alpha}M + vT is an n x n symmetric positive definite matrix, in which M is the mass matrix, T is the discrete Laplace operator, {alpha} and {nu} are positive constants proportional to the inverses of the time-step {Delta}t and the Reynolds number Re respectively, and B is the discrete gradient operator of size n x k (k < n). Even though the matrix A is symmetric and positive definite, the system is indefinite due to the incompressibility constraint (B{sup T}u = 0). This causes difficulties both for iterative methods and commonly used preconditioners. Moreover, depending on the ratio {alpha}/{nu}, A behaves like the mass matrix M at one extreme and the Laplace operator T at the other, thus complicating the issue of preconditioning.
Cascaded forward Brillouin scattering to all Stokes orders
Wolff, C.; Stiller, B.; Eggleton, B. J.; Steel, M. J.; Poulton, C. G.
2017-02-01
Inelastic scattering processes such as Brillouin scattering can often function in cascaded regimes and this is likely to occur in certain integrated opto-acoustic devices. We develop a Hamiltonian formalism for cascaded Brillouin scattering valid for both quantum and classical regimes. By regarding Brillouin scattering as the interaction of a single acoustic envelope and a single optical envelope that covers all Stokes and anti-Stokes orders, we obtain a compact model that is well suited for numerical implementation, extension to include other optical nonlinearities or short pulses, and application in the quantum-optics domain. We then theoretically analyze intra-mode forward Brillouin scattering (FBS) for arbitrary waveguides with and without optical dispersion. In the absence of optical dispersion, we find an exact analytical solution. With a perturbative approach, we furthermore solve the case of weak optical dispersion. Our work leads to several key results on intra-mode FBS. For negligible dispersion, we show that cascaded intra-mode FBS results in a pure phase modulation and discuss how this necessitates specific experimental methods for the observation of fiber-based and integrated FBS. Further, we discuss how the descriptions that have been established in these two classes of waveguides connect to each other and to the broader context of cavity opto-mechanics and Raman scattering. Finally, we draw an unexpected striking similarity between FBS and discrete diffraction phenomena in waveguide arrays, which makes FBS an interesting candidate for future research in quantum-optics.
High-order Stokes and anti-Stokes Raman generation in monoisotopic CVD {sup 12}C-diamond
Energy Technology Data Exchange (ETDEWEB)
Kaminskii, Alexander A. [Institute of Crystallography, Russian Academy of Sciences, Moscow (Russian Federation); Lux, Oliver; Rhee, Hanjo; Eichler, Hans J. [Institute of Optics and Atomic Physics, Technische Universitaet Berlin (Germany); Ralchenko, Victor G.; Bolshakov, Andrey P. [General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Shirakawa, Akira; Yoneda, Hitoki [Institute for Laser Science, University of Electro-Communications, Tokyo (Japan)
2016-06-15
We determined, for the first time, the room temperature phonon energy related to the F{sub 2g} vibration mode (ω{sub SRS(12C)} ∝ 1333.2 cm{sup -1}) in a mono-crystalline single-isotope CVD {sup 12}C-diamond crystal by means of stimulated Raman scattering (SRS) spectroscopy. Picosecond one-micron excitation using a Nd{sup 3+}:Y{sub 3}Al{sub 5}O{sub 12}-laser generates a nearly two-octave spanning SRS frequency comb (∝12000 cm{sup -1}) consisting of higher-order Stokes and anti-Stokes components. The spacing of the spectral lines was found to differ by Δω{sub SRS} ∝ 0.9 cm{sup -1} from the comb spacing (ω{sub SRS(natC)} ∝ 1332.3 cm{sup -1}) when pumping a conventional CVD diamond crystal with a natural composition of the two stable carbon isotopes {sup 12}C (98.93%) and {sup 13}C (1.07%). (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Directory of Open Access Journals (Sweden)
Miryam Lucía Guerra-Mazo
2016-05-01
Full Text Available Presenta los resultados de la comparación entre las ecuaciones de Stokes y de Navier-Stokes para la simulación del flujo de agua líquida, a condiciones atmosféricas, a través de una placa orificio concéntrica. A partir de los datos experimentales que fueron tomados en el banco de fluidos, se evaluaron las simulaciones de ambas ecuaciones, usando el software libre Freefem++cs, que se basa en el método de los elementos finitos; las variables evaluadas son velocidad y presión en un intervalo de tiempo. Al analizar los resultados obtenidos con las simulaciones y comparar con los datos experimentales se encontró que las ecuaciones de Navier-Stokes representan mejor el sistema que la ecuación de Stokes.
1979-09-01
KASKASKIA. ST. LOUIS BAS WOODRIDGE LAKE DAM WARREN COUNTY, MISSOURI MO 11005 (9) Final rept., DACW43-79-C.-#A)75 J (i) Sep 79 (10) Walter G. /Shifrin...Dam Inspection Report National Dam Safety Program Final Report Woodridge Lake Dam (MO 11005) 6. PERFORMING ORG. REPORT NUMBER Warren County, Missouri 7...Norvell Construction of 3320 Hermoso St., St. Louis, MO. After the structure was completed, a 2 inch water- line with a water faucet was installed on the
Moreland-Russell, Sarah; Cyr, Julianne; Benson, Peter; Colditz, Graham; Pulley, Deren; Barnoya, Joaquin
2012-01-01
This cross-sectional study provides information about secondhand smoke exposure across the St. Louis metro area and perceptions and attitudes about tobacco and health within the local hospitality industry. Results from this study support the need for passage and implementation of comprehensive smoke-free laws throughout Missouri, particularly in St. Louis City and County where efforts to pass comprehensive smoke-free laws have been unsuccessful.
Investigation of Navier-Stokes Code Verification and Design Optimization
Vaidyanathan, Rajkumar
2004-01-01
With rapid progress made in employing computational techniques for various complex Navier-Stokes fluid flow problems, design optimization problems traditionally based on empirical formulations and experiments are now being addressed with the aid of computational fluid dynamics (CFD). To be able to carry out an effective CFD-based optimization study, it is essential that the uncertainty and appropriate confidence limits of the CFD solutions be quantified over the chosen design space. The present dissertation investigates the issues related to code verification, surrogate model-based optimization and sensitivity evaluation. For Navier-Stokes (NS) CFD code verification a least square extrapolation (LSE) method is assessed. This method projects numerically computed NS solutions from multiple, coarser base grids onto a freer grid and improves solution accuracy by minimizing the residual of the discretized NS equations over the projected grid. In this dissertation, the finite volume (FV) formulation is focused on. The interplay between the xi concepts and the outcome of LSE, and the effects of solution gradients and singularities, nonlinear physics, and coupling of flow variables on the effectiveness of LSE are investigated. A CFD-based design optimization of a single element liquid rocket injector is conducted with surrogate models developed using response surface methodology (RSM) based on CFD solutions. The computational model consists of the NS equations, finite rate chemistry, and the k-6 turbulence closure. With the aid of these surrogate models, sensitivity and trade-off analyses are carried out for the injector design whose geometry (hydrogen flow angle, hydrogen and oxygen flow areas and oxygen post tip thickness) is optimized to attain desirable goals in performance (combustion length) and life/survivability (the maximum temperatures on the oxidizer post tip and injector face and a combustion chamber wall temperature). A preliminary multi-objective optimization
Jenkins Morales, Meghan; King, M Denise; Hiler, Hattie; Coopwood, Martin S; Wayland, Sherrill
2014-01-01
This study sought to understand differences and similarities between lesbian, gay, bisexual, and transgender (LGBT) Baby Boomers and members of the Silent generation in the greater St. Louis region in relation to perceived barriers to service use, LGBT identity disclosure, experiences of violence and victimization, and mental health. An online survey was completed by 118 Baby Boomers and 33 Silents. Baby Boomers were found to perceive more barriers to health care and legal services, have fewer legal documents in place, feel less safe in their communities, and have experienced an increased rate of verbal harassment compared to their predecessors. Differences may be attributed to higher levels of LGBT identity disclosure among Baby Boomers across their lifetime. These findings support the current work of Services and Advocacy for GLBT Elders Metro St. Louis, with implications for other communities, and shed light on the need for continued advancement in the development and implementation of programs as LGBT Baby Boomers age.
Approximate theory of Stokes amplification and conversion valid at large gain
Energy Technology Data Exchange (ETDEWEB)
Druehl, K.J.; Shakir, S.; Yousaf, M.
1986-07-01
We predict Stokes-beam divergence, origin, and gain for large-gain Raman amplifiers as functions of pump-beam divergence and pump power in terms of simple analytical expressions. Stokes divergence is found to peak at a pump power twice above threshold. Results are in excellent agreement with exact computer solutions and explain recent experimental observations.
UNIFORMLY-STABLE FINITE ELEMENT METHODS FOR DARCY-STOKES-BRINKMAN MODELS
Institute of Scientific and Technical Information of China (English)
Xiaoping Xie; Jinchao Xu; Guangri Xue
2008-01-01
In this paper, we consider 2D and 3D Darcy-Stokes interface problems. These equations are related to Brinkman model that treats both Darcy's law and Stokes equations in a single form of PDE but with strongly discontinuous viscosity coefficient and zerothorder term coefficient. We present three different methods to construct uniformly stable finite element approximations. The first two methods are based on the original weak formulations of Darcy-Stokes-Brinkman equations. In the first method we consider the existing Stokes elements. We show that a stable Stokes element is also uniformly stable with respect to the coefficients and the jumps of Darcy-Stokes-Brinkman equations if and only if the discretely divergence-free velocity implies almost everywhere divergence-free one. In the second method we construct uniformly stable elements by modifying some well-known H(div)-conforming elements. We give some new 2D and 3D elements in a unified way. In the last method we modify the original weak formulation of Darcy-Stokes-Brinkman equations with a stabilization term. We show that all traditional stable Stokes elements are uniformly stable with respect to the coefficients and their jumps under this new formulation.
DEFF Research Database (Denmark)
Andresen, Esben Ravn; Paulsen, Henrik Nørgaard; Birkedal, Victoria;
2006-01-01
We demonstrate spectral multiplex coherent anti-Stokes Raman scattering (CARS) spectroscopy and microscopy based on a single Ti:sapphire oscillator and a nonlinear photonic-crystal fiber (PCF). The Stokes pulse is generated by spectral conversion of the laser pulse in a PCF. The pump pulse...
Feireisl, Eduard; Novotny, Antonin
2011-01-01
We introduce the notion of relative entropy for the weak solutions of the compressible Navier-Stokes system. We show that any finite energy weak solution satisfies a relative entropy inequality for any pair of sufficiently smooth test functions. As a corollary we establish weak-strong uniqueness principle for the compressible Navier-Stokes system.
SOLUTION OF 3-D TURBULENCE NAVIER-STOKES EQUATIONS USING HYBRID GRIDS
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Hybrid grids are used for the solution of 3D turbulence Navier-Stokes equations. The prismatic grids are generated near the wall, and the tetrahedron grids are generated in the other field. A Navier-Stokes solver using ic Baldwin-Lomax turbulence model is adopted. The numerical tests show that the above method is very efficient.``
1980-09-01
the extension of Chippewa Street) against a 52-foot Mississippi River flood stage ( Market Street gage). Details regarding the overall city of St. Louis...significantly contribute to outdoor recreation objective by increasing the opportunity for such activities as nature hiking and birdwatching . wildlife...resources related to any proposed project. The changes may be of a market or non- market character, but generally the latter. Such effects are inextricably
Directory of Open Access Journals (Sweden)
Deepti eAdlakha
2014-05-01
Full Text Available IntroductionAbundant evidence shows that regular physical activity (PA is an effective strategy for preventing obesity in people of diverse socioeconomic status (SES and race groups. The proportion of PA performed in parks and how this differs by proximate neighborhood SES has not been thoroughly investigated. The present project analyzes online public web data feeds to assess differences in outdoor PA by neighborhood SES in St. Louis, Missouri, US.MethodsFirst, running and walking routes submitted by users of the website MapMyRun.com were downloaded. The website enables participants to plan, map, record, and share their exercise routes and outdoor activities like runs, walks, and hikes in an online database. Next, the routes were visually illustrated using Geographic Information Systems (GIS. Thereafter, using park data and 2010 Missouri census poverty data, the odds of running and walking routes traversing a low-SES neighborhood, and traversing a park in a low-SES neighborhood were examined in comparison to routes in high-SES neighborhoods and high-SES parks.Results Results show that a majority of running and walking routes occur in, or at least traverse through a park. However, this finding does not hold when comparing low-SES neighborhoods to higher-SES neighborhoods in St. Louis. The odds of running in a park in a low-SES neighborhood were 54 percent lower than running in a park in a higher-SES neighborhood (OR=0.46, CI=0.17-1.23. The odds of walking in a park in a low-SES neighborhood were 17 percent lower than walking in a park in a higher-SES neighborhood (OR = 0.83, CI = 0.26-2.61.ConclusionsThe novel methods of this study include the use of inexpensive, unobtrusive, and publicly available web data feeds to evaluate PA in parks and differences by neighborhood SES. Emerging technologies like MapMyRun.com present significant advantages to enhance tracking of user-defined PA across large geographic and temporal settings.
Computerized Stokes analysis of optically active polymer films
Georgiev, Georgi
2010-01-01
Optics labs are an integral part of the advanced curriculum for physics majors. Students majoring in other disciplines, like chemistry, biology or engineering rarely have the opportunity to learn about the most recent optical techniques and mathematical representation used in todayâs science and industry optics. Stokes analysis of polarization of light is one of those methods that are increasingly necessary but are seldom taught outside advanced physics or optics classes that are limited to physics majors. On the other hand biology and chemistry majors already use matrix and polarization techniques in the labs for their specialty, which makes the transition to matrix calculations seamless. Since most of the students in those majors postpone their enrollment in physics, most of the registered in those classes are juniors and seniors, enabling them to handle those techniques. We chose to study polymer samples to aid students majoring in other disciplines, especially chemistry and engineering, with understa...
Relationship between central sleep apnea and Cheyne-Stokes Respiration.
Flinta, Irena; Ponikowski, Piotr
2016-03-01
Central sleep apnea (CSA) in patients with heart failure (HF) occurs frequently and shows a serious influence on prognosis in this population. The key elements in the pathophysiology of CSA are respiratory instability with chronic hyperventilation, changes of arterial carbon dioxide pressure (pCO2) and elongated circulation time. The main manifestation of CSA in patients with HF is Cheyne-Stokes Respiration (CSR). The initial treatment is the optimization of HF therapy. However, many other options of the therapeutic management have been studied, particularly those based on positive airway pressure methods. In patients with heart failure we often can observe the overlap of CSA and CSR; we will discuss the differences between these forms of breathing disorders during sleep. We will also discuss when CSA and CSR occur independently of each other and the importance of CSR occurring during the daytime in context of CSA during the nighttime.
Navier-Stokes Dynamics by a Discrete Boltzmann Model
Rubinstein, Robet
2010-01-01
This work investigates the possibility of particle-based algorithms for the Navier-Stokes equations and higher order continuum approximations of the Boltzmann equation; such algorithms would generalize the well-known Pullin scheme for the Euler equations. One such method is proposed in the context of a discrete velocity model of the Boltzmann equation. Preliminary results on shock structure are consistent with the expectation that the shock should be much broader than the near discontinuity predicted by the Pullin scheme, yet narrower than the prediction of the Boltzmann equation. We discuss the extension of this essentially deterministic method to a stochastic particle method that, like DSMC, samples the distribution function rather than resolving it completely.
Models of Cheyne-Stokes respiration with cardiovascular pathologies.
Dong, Fang; Langford, William F
2008-10-01
Cheyne-Stokes respiration (CSR) is a periodic breathing pattern, characterized by short intervals of very little or no breathing (apnea), each followed by an interval of very heavy breathing (hyperpnea). This work presents a new compartmental model of the human cardio-respiratory system, simulating the factors that determine the concentrations of carbon dioxide in the compartments of the cardiovascular system and the lungs. The parameter set on which a Hopf bifurcation gives birth to stable CSR oscillations has been determined. The model predicts that the onset of CSR oscillations may result from an increase in any of: ventilation-perfusion ratio, feedback control gain, transport delay, left heart volume, lung congestion, or cardiovascular efficiency. The model is employed to investigate the relationship between CSR and serious cardiovascular pathologies, such as congestive heart failure and encephalitis, as well as the effects of acclimatization to higher altitudes. In all cases, the model is consistent with medical observations.
Quantitative coherent anti-Stokes Raman scattering (CARS) microscopy.
Day, James P R; Domke, Katrin F; Rago, Gianluca; Kano, Hideaki; Hamaguchi, Hiro-o; Vartiainen, Erik M; Bonn, Mischa
2011-06-23
The ability to observe samples qualitatively at the microscopic scale has greatly enhanced our understanding of the physical and biological world throughout the 400 year history of microscopic imaging, but there are relatively few techniques that can truly claim the ability to quantify the local concentration and composition of a sample. We review coherent anti-Stokes Raman scattering (CARS) as a quantitative, chemically specific, and label-free microscopy. We discuss the complicating influence of the nonresonant response on the CARS signal and the various experimental and mathematical approaches that can be adopted to extract quantitative information from CARS. We also review the uses to which CARS has been employed as a quantitative microscopy to solve challenges in material and biological science.
Coherent anti-Stokes Raman scattering microscopy of single nanodiamonds.
Pope, Iestyn; Payne, Lukas; Zoriniants, George; Thomas, Evan; Williams, Oliver; Watson, Peter; Langbein, Wolfgang; Borri, Paola
2014-11-01
Nanoparticles have attracted enormous attention for biomedical applications as optical labels, drug-delivery vehicles and contrast agents in vivo. In the quest for superior photostability and biocompatibility, nanodiamonds are considered one of the best choices due to their unique structural, chemical, mechanical and optical properties. So far, mainly fluorescent nanodiamonds have been utilized for cell imaging. However, their use is limited by the efficiency and costs in reliably producing fluorescent defect centres with stable optical properties. Here, we show that single non-fluorescing nanodiamonds exhibit strong coherent anti-Stokes Raman scattering (CARS) at the sp(3) vibrational resonance of diamond. Using correlative light and electron microscopy, the relationship between CARS signal strength and nanodiamond size is quantified. The calibrated CARS signal in turn enables the analysis of the number and size of nanodiamonds internalized in living cells in situ, which opens the exciting prospect of following complex cellular trafficking pathways quantitatively.
Coherent anti-Stokes Raman scattering microscopy of single nanodiamonds
Pope, Iestyn; Payne, Lukas; Zoriniants, George; Thomas, Evan; Williams, Oliver; Watson, Peter; Langbein, Wolfgang; Borri, Paola
2014-11-01
Nanoparticles have attracted enormous attention for biomedical applications as optical labels, drug-delivery vehicles and contrast agents in vivo. In the quest for superior photostability and biocompatibility, nanodiamonds are considered one of the best choices due to their unique structural, chemical, mechanical and optical properties. So far, mainly fluorescent nanodiamonds have been utilized for cell imaging. However, their use is limited by the efficiency and costs in reliably producing fluorescent defect centres with stable optical properties. Here, we show that single non-fluorescing nanodiamonds exhibit strong coherent anti-Stokes Raman scattering (CARS) at the sp3 vibrational resonance of diamond. Using correlative light and electron microscopy, the relationship between CARS signal strength and nanodiamond size is quantified. The calibrated CARS signal in turn enables the analysis of the number and size of nanodiamonds internalized in living cells in situ, which opens the exciting prospect of following complex cellular trafficking pathways quantitatively.
Navier-Stokes equations on R3 × [0, T
Stenger, Frank; Baumann, Gerd
2016-01-01
In this monograph, leading researchers in the world of numerical analysis, partial differential equations, and hard computational problems study the properties of solutions of the Navier–Stokes partial differential equations on (x, y, z, t) ∈ ℝ3 × [0, T]. Initially converting the PDE to a system of integral equations, the authors then describe spaces A of analytic functions that house solutions of this equation, and show that these spaces of analytic functions are dense in the spaces S of rapidly decreasing and infinitely differentiable functions. This method benefits from the following advantages: The functions of S are nearly always conceptual rather than explicit Initial and boundary conditions of solutions of PDE are usually drawn from the applied sciences, and as such, they are nearly always piece-wise analytic, and in this case, the solutions have the same properties When methods of approximation are applied to functions of A they converge at an exponential rate, whereas methods of approximation ...
Navier-Stokes analysis of turbomachinery blade external heat transfer
Ameri, A. A.; Sockol, P. M.; Gorla, R. S. R.
1992-01-01
The two-dimensional, compressible, thin-layer Navier-Stokes and energy equations were solved numerically to obtain heat transfer rates on turbomachinery blades. The Baldwin-Lomax algebraic model and the q - omega low Reynolds number, two-equation model were used for modeling of turbulence. For the numerical solution of the governing equations a four-stage Runge-Kutta solver was employed. The turbulence model equations were solved using an implicit scheme. Numerical solutions are presented for two-dimensional flow within two vane cascades. The heat transfer results and the pressure distributions were compared with published experimental data. The agreement between the numerical calculations and the experimental values were found to be generally favorable. The position of transition from laminar to turbulent flow was also predicted accurately.
Aerodynamics of thrust vectoring by Navier-Stokes solutions
Tseng, Jing-Biau; Lan, C. Edward
1991-01-01
Induced aerodynamics from thrust vectoring are investigated by a computational fluid dynamic method. A thin-layer Reynolds-averaged Navier-Stokes code with multiblock capability is used. Jet properties are specified on the nozzle exit plane to simulate the jet momentum. Results for a rectangular jet in a cross flow are compared with data to verify the code. Further verification of the calculation is made by comparing the numerical results with transonic data for a wing-body combination. Additional calculations were performed to elucidate the following thrust vectoring effects: the thrust vectoring effect on shock and expansion waves, induced effects on nearby surfaces, and the thrust vectoring effect on the leading edge vortex.
Beyond the Navier-Stokes equations: Burnett hydrodynamics
Energy Technology Data Exchange (ETDEWEB)
Garcia-Colin, L.S. [Department of Physics, Universidad Autonoma Metropolitana - Iztapalapa, Mexico D. F. 09340 (Mexico); El Colegio Nacional, Centro Historico, Mexico, 06020 (Mexico)], E-mail: lgcs@xanum.uam.mx; Velasco, R.M. [Department of Physics, Universidad Autonoma Metropolitana - Iztapalapa, Mexico D. F. 09340 (Mexico)], E-mail: rmvb@xanum.uam.mx; Uribe, F.J. [Department of Physics, Universidad Autonoma Metropolitana - Iztapalapa, Mexico D. F. 09340 (Mexico)], E-mail: paco@xanum.uam.mx
2008-08-15
This work is mainly concerned with the extension of hydrodynamics beyond the Navier-Stokes equations, a regime known as Burnett hydrodynamics. The derivation of the Burnett equations is considered from several theoretical approaches. In particular we discuss the Chapman-Enskog, Grad's method, and Truesdell's approach for solving the Boltzmann equation. Also, their derivation using the macroscopic approach given by extended thermodynamics is mentioned. The problems and successes of these equations are discussed and some alternatives proposed to improve them are mentioned. Comparisons of the predictions coming from the Burnett equations with experiments and/or simulations are given in order to have the necessary elements to give a critical assessment of their validity and usefulness.
Solving the Stokes problem on a massively parallel computer
DEFF Research Database (Denmark)
Axelsson, Owe; Barker, Vincent A.; Neytcheva, Maya
2001-01-01
We describe a numerical procedure for solving the stationary two‐dimensional Stokes problem based on piecewise linear finite element approximations for both velocity and pressure, a regularization technique for stability, and a defect‐correction technique for improving accuracy. Eliminating...... boundary value problem for each velocity component, are solved by the conjugate gradient method with a preconditioning based on the algebraic multi‐level iteration (AMLI) technique. The velocity is found from the computed pressure. The method is optimal in the sense that the computational work...... is proportional to the number of unknowns. Further, it is designed to exploit a massively parallel computer with distributed memory architecture. Numerical experiments on a Cray T3E computer illustrate the parallel performance of the method....
General inverse of Stokes, Vening-Meinesz and Molodensky formulae
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
The operator operations between the disturbing potential and the geoidal undulation, the gravity anomaly, the deflection of the vertical are defined based on the relations among the gravity potential, the normal gravity potential and the disturbing potential. With the sphere as the boundary surface, based on the solution of the external boundary value problem for the disturbing potential by the spherical harmonics in the physical geodesy, the general inverse Stokes' formula, the general inverse Vening-Meinesz formula and the general Molodensky's formula are derived from the operator operations defined. The general formulae can get rid of the restriction of the classical formulae only used on the geoid. If the boundary surface is defined as the geoid, the general formulas are degenerated into the classic ones.
Chern-Simons theory, Stokes' Theorem, and the Duflo map
Sahlmann, Hanno
2011-01-01
We consider a novel derivation of the expectation values of holonomies in Chern-Simons theory, based on Stokes' Theorem and the functional properties of the Chern-Simons action. It involves replacing the connection by certain functional derivatives under the path integral integral. It turns out that ordering choices have to be made in the process, and we demonstrate that, quite surprisingly, the Duflo isomorphism gives the right ordering, at least in the simple cases that we consider. In this way, we determine the expectation values of unknotted, but possibly linked, holonomy loops for SU(2) and SU(3), and sketch how the method may be applied to more complicated cases. Our manipulations of the path integral are formal but well motivated by a rigorous calculus of integration on spaces of generalized connections which has been developed in the context of loop quantum gravity.
Effects of Stokes production on summer ocean shelf dynamics
Institute of Scientific and Technical Information of China (English)
ZHANG Xuefeng; HANGuijun; WANG Xidong; ZHANG Lianxin
2014-01-01
A two-dimensional numerical model, which is configured on the basis of Princeton ocean model (POM), is used to study the effect of Stokes production (SP) of the turbulent kinetic energy on a density profile and Ekman transport in an idealized shelf region in summer. The energy input from SP is parameterized and included into the Mellor-Yamada turbulence closure submodel. Results reveal that the intensity of wind-driven upwelling fronts near the sea surface is weakened by the SP-associated turbulent kinetic energy input. The vertical eddy viscosity coefficient in the surface boundary layer is enhanced greatly owing to the impact of SP, which decreases the alongshore velocity and changes the distribution of upwelling. In addition, the SP-induced mixing easily suppresses the strong stratification and significantly increases the depth of the upper mixed layer (ML) under strong winds.
Stokes integral of economic growth. Calculus and the Solow model
Mimkes, Jürgen
2010-04-01
Economic growth depends on capital and labor and two-dimensional calculus has been applied to economic theory. This leads to Riemann and Stokes integrals and to the first and second laws of production and growth. The mathematical structure is the same as in thermodynamics, economic properties may be related to physical terms: capital to energy, production to physical work, GDP per capita to temperature, production function to entropy. This is called econophysics. Production, trade and banking may be compared to motors, heat pumps or refrigerators. The Carnot process of the first law creates two levels in each system: cold and hot in physics; buyer and seller, investor and saver, rich and poor in economics. The efficiency rises with the income difference of rich and poor. The results of econophysics are compared to neoclassical theory.
Fast and spectrally accurate summation of 2-periodic Stokes potentials
Lindbo, Dag
2011-01-01
We derive a Ewald decomposition for the Stokeslet in planar periodicity and a novel PME-type O(N log N) method for the fast evaluation of the resulting sums. The decomposition is the natural 2P counterpart to the classical 3P decomposition by Hasimoto, and is given in an explicit form not found in the literature. Truncation error estimates are provided to aid in selecting parameters. The fast, PME-type, method appears to be the first fast method for computing Stokeslet Ewald sums in planar periodicity, and has three attractive properties: it is spectrally accurate; it uses the minimal amount of memory that a gridded Ewald method can use; and provides clarity regarding numerical errors and how to choose parameters. Analytical and numerical results are give to support this. We explore the practicalities of the proposed method, and survey the computational issues involved in applying it to 2-periodic boundary integral Stokes problems.
Stokes Waves Revisited: Exact Solutions in the Asymptotic Limit
Davies, Megan
2016-01-01
Stokes perturbative solution of the nonlinear (boundary value dependent) surface gravity wave problem is known to provide results of reasonable accuracy to engineers in estimating the phase speed and amplitudes of such nonlinear waves. The weakling in this structure though is the presence of aperiodic secular variation in the solution that does not agree with the known periodic propagation of surface waves. This has historically necessitated increasingly higher ordered (perturbative) approximations in the representation of the velocity profile. The present article ameliorates this long standing theoretical insufficiency by invoking a compact exact $n$-ordered solution in the asymptotic infinite depth limit, primarily based on a representation structured around the third ordered perturbative solution, that leads to a seamless extension to higher order (e.g. fifth order) forms existing in the literature. The result from this study is expected to improve phenomenological engineering estimates, now that any desir...
Noninvasive diagnosis of oral cancer by Stokes shift spectroscopy
Ebenezar, Jeyasingh; Ganesan, Singaravelu; Aruna, Prakasrao; Muralinaidu, Radhakrishnan
2014-03-01
The objective of this study is to evaluate the diagnostic potential of stokes shift (SS) spectroscopy (S3) for normal, precancer and cancerous oral lesions in vivo. The SS spectra were recorded in the 250 - 650 nm spectral range by simultaneously scanning both the excitation and emission wavelengths while keeping a fixed wavelength interval Δλ=20 nm between them. Characteristic, highly resolved peaks and significant spectral differences between normal and different pathological oral lesions observed around 300, 355, 395, and 420 nm which are attributed to tryptophan, collagen, and NADH respectively. Using S3 technique one can obtain the key fluorophores in a single scan and hence they can be targeted as a tumor markers in this study. In order to quantify the altered spectral differences between normal and different pathological oral lesions are verified by different ratio parameters.
Imaging properties of coherent anti-Stokes Raman scattering microscope
Institute of Scientific and Technical Information of China (English)
Yuan Jing-He; Xiao Fan-Rong; Wang Gui-Ying; Xu Zhi-Zhan
2005-01-01
The coherent anti-Stokes Raman scattering (CARS) microscope with the combination of confocal and CARS techniques is a remarkable alternative for imaging chemical or biological specimens that neither fluoresce nor tolerate labelling. CARS is a nonlinear optical process, the imaging properties of CARS microscopy will be very different from the conventional confocal microscope. In this paper, the intensity distribution and the polarization property of the optical field near the focus was calculated. By using the Green function, the precise analytic solution to the wave equation of a Hertzian dipole source was obtained. We found that the intensity distributions vary considerably with the different experimental configurations and the different specimen shapes. So the conventional description of microscope (e.g. the point spread function) will fail to describe the imaging properties of the CARS microscope.
Perturbation of eigenvalues of preconditioned Navier-Stokes operators
Energy Technology Data Exchange (ETDEWEB)
Elman, H.C. [Univ. of Maryland, College Park, MD (United States)
1996-12-31
We study the sensitivity of algebraic eigenvalue problems associated with matrices arising from linearization and discretization of the steady-state Navier-Stokes equations. In particular, for several choices of preconditioners applied to the system of discrete equations, we derive upper bounds on perturbations of eigenvalues as functions of the viscosity and discretization mesh size. The bounds suggest that the sensitivity of the eigenvalues is at worst linear in the inverse of the viscosity and quadratic in the inverse of the mesh size, and that scaling can be used to decrease the sensitivity in some cases. Experimental results supplement these results and confirm the relatively mild dependence on viscosity. They also indicate a dependence on the mesh size of magnitude smaller than the analysis suggests.
Iterative methods for compressible Navier-Stokes and Euler equations
Energy Technology Data Exchange (ETDEWEB)
Tang, W.P.; Forsyth, P.A.
1996-12-31
This workshop will focus on methods for solution of compressible Navier-Stokes and Euler equations. In particular, attention will be focused on the interaction between the methods used to solve the non-linear algebraic equations (e.g. full Newton or first order Jacobian) and the resulting large sparse systems. Various types of block and incomplete LU factorization will be discussed, as well as stability issues, and the use of Newton-Krylov methods. These techniques will be demonstrated on a variety of model transonic and supersonic airfoil problems. Applications to industrial CFD problems will also be presented. Experience with the use of C++ for solution of large scale problems will also be discussed. The format for this workshop will be four fifteen minute talks, followed by a roundtable discussion.
Thermoelectric DC conductivities and Stokes flows on black hole horizons
Banks, Elliot; Gauntlett, Jerome P
2015-01-01
We consider a general class of electrically charged black holes of Einstein-Maxwell-scalar theory that are holographically dual to conformal field theories at finite charge density which break translation invariance explicitly. We examine the linearised perturbations about the solutions that are associated with the thermoelectric DC conductivity. We show that there is a decoupled sector at the black hole horizon which must solve generalised Stokes equations for a charged fluid. By solving these equations we can obtain the DC conductivity of the dual field theory. For one-dimensional lattices we solve the fluid equations to obtain closed form expressions for the DC conductivity in terms of the solution at the black hole horizon. We also determine the leading order DC conductivity for lattices that can be expanded as a perturbative series about translationally invariant solutions.
The Navier-Stokes equations an elementary functional analytic approach
Sohr, Hermann
2001-01-01
The primary objective of this monograph is to develop an elementary and self-contained approach to the mathematical theory of a viscous, incompressible fluid in a domain of the Euclidean space, described by the equations of Navier-Stokes. Moreover, the theory is presented for completely general domains, in particular, for arbitrary unbounded, nonsmooth domains. Therefore, restriction was necessary to space dimensions two and three, which are also the most significant from a physical point of view. For mathematical generality, however, the linearized theory is expounded for general dimensions higher than one. Although the functional analytic approach developed here is, in principle, known to specialists, the present book fills a gap in the literature providing a systematic treatment of a subject that has been documented until now only in fragments. The book is mainly directed to students familiar with basic tools in Hilbert and Banach spaces. However, for the readers’ convenience, some fundamental properties...
Analyzing the Data from X-ray Polarimeters with Stokes Parameters
Kislat, F; Beilicke, M; Krawczynski, H
2014-01-01
X-ray polarimetry promises to deliver unique information about the geometry of the inner accretion flow of astrophysical black holes and the nature of matter and electromagnetism in and around neutron stars. In this paper, we discuss the possibility to use Stokes parameters - a commonly used tool in radio, infrared, and optical polarimetry - to analyze the data from X-ray polarimeters such as scattering polarimeters and photoelectric effect polarimeters, which measure the linear polarization of the detected X-rays. Based on the azimuthal scattering angle (in the case of a scattering polarimeter) or the azimuthal component of the angle of the electron ejection (in the case of a photoelectric effect polarimeter), the Stokes parameters can be calculated for each event recorded in the detector. Owing to the additive nature of Stokes parameters, the analysis reduces to adding the Stokes parameters of the individual events and subtracting the Stokes parameters characterizing the background (if present). The main st...
Optimal distribution of integration time for intensity measurements in Stokes polarimetry.
Li, Xiaobo; Liu, Tiegen; Huang, Bingjing; Song, Zhanjie; Hu, Haofeng
2015-10-19
We consider the typical Stokes polarimetry system, which performs four intensity measurements to estimate a Stokes vector. We show that if the total integration time of intensity measurements is fixed, the variance of the Stokes vector estimator depends on the distribution of the integration time at four intensity measurements. Therefore, by optimizing the distribution of integration time, the variance of the Stokes vector estimator can be decreased. In this paper, we obtain the closed-form solution of the optimal distribution of integration time by employing Lagrange multiplier method. According to the theoretical analysis and real-world experiment, it is shown that the total variance of the Stokes vector estimator can be significantly decreased about 40% in the case discussed in this paper. The method proposed in this paper can effectively decrease the measurement variance and thus statistically improves the measurement accuracy of the polarimetric system.
High Precision Stokes Polarimetry for Scattering Light using Wide Dynamic Range Intensity Detector
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Shibata Shuhei
2015-01-01
Full Text Available This paper proposes a Stokes polarimetry for scattering light from a sample surface. To achieve a high accuracy measurement two approaches of an intensity detector and analysis algorism of a Stokes parameter were proposed. The dynamic range of this detector can achieve up to 1010 by combination of change of neutral-density (ND filters having different density and photon counting units. Stokes parameters can be measured by dual rotating of a retarder and an analyzer. The algorism of dual rotating polarimeter can be calibrated small linear diattenuation and linear retardance error of the retarder. This system can measured Stokes parameters from −20° to 70° of its scattering angle. It is possible to measure Stokes parameters of scattering of dust and scratch of optical device with high precision. This paper shows accuracy of this system, checking the polarization change of scattering angle and influence of beam size.
Methods for the coupled Stokes-Darcy problem
Feuillebois, F.; Khabthani, S.; Elasmi, L.; Sellier, A.
2010-11-01
The motion of particles in a viscous fluid close to a porous membrane is modelled for the case when particles are large compared with the size of pores of the membrane. The hydrodynamic interactions of one particle with the membrane are detailed here. The model involves Stokes equations for the fluid motion around the particle together with Darcy equations for the flow in the porous membrane and Stokes equations for the flow on the other side of the membrane. Boundary conditions at the fluid-membrane interface are the continuity of pressure and velocity in the normal direction and the Beavers and Joseph slip condition on the fluid side in the tangential directions. The no-slip condition applies on the particle. This problem is solved here by two different methods. The first one is an extended boundary integral method (EBIM). A Green function is derived for the flow close to a porous membrane. This function is non-symmetric, leading to difficulties hindering the application of the classical boundary integral method (BIM). Thus, an extended method is proposed, in which the unknown distribution of singularities on the particle surface is not the stress, like in the classical boundary integral method. Yet, the hydrodynamic force and torque on the particle are obtained by integrals of this distribution on the particle surface. The second method consists in searching the solution as an asymptotic expansion in term of a small parameter that is the ratio of the typical pore size to the particle size. The various boundary conditions are taken into account at successive orders: order (0) simply represents an impermeable wall without slip and order (1) an impermeable wall with a peculiar slip prescribed by order (0); at least the 3rd order is necessary to enforce all boundary conditions. The methods are applied numerically to a spherical particle and comparisons are made with earlier works in particular cases.
Charlier, Philippe; Olalde, Iñigo; Solé, Neus; Ramírez, Oscar; Babelon, Jean-Pierre; Galland, Bruno; Calafell, Francesc; Lalueza-Fox, Carles
2013-03-10
A mummified head was identified in 2010 as belonging to Henri IV, King of France. A putative blood sample from the King Louis XVI preserved into a pyrographically decorated gourd was analyzed in 2011. Both kings are in a direct male-line descent, separated by seven generations. We have retrieved the hypervariable region 1 of the mitochondrial DNA as well as a partial Y-chromosome profile from Henri IV. Five STR loci match the alleles found in Louis XVI, while another locus shows an allele that is just one mutation step apart. Taking into consideration that the partial Y-chromosome profile is extremely rare in modern human databases, we concluded that both males could be paternally related. The likelihood ratio of the two samples belonging to males separated by seven generations (as opposed to unrelated males) was estimated as 246.3, with a 95% confidence interval between 44.2 and 9729. Historically speaking, this forensic DNA data would confirm the identity of the previous Louis XVI sample, and give another positive argument for the authenticity of the head of Henri IV.
Ehrlich, G.G.; Goerlitz, D.F.; Godsy, E.M.; Hult, M.F.
1982-01-01
Coal-tar derivatives from a coal-tar distillation and wood-treating plant that operated from 1918 to 1972 at St. Louis Park, Minnesota contaminated the near-surface ground water. Solutions of phenolic compounds and a water-immiscible mixture of polynuclear aromatic compounds accumulated in wetlands near the plant site and entered the aquifer. The concentration of phenolic compounds in the aqueous phase under the wetlands is about 30 mg/1 but decreases to less than 0.2 mg/1 at a distance of 430 m immediately downgradient from the source. Concentrations of naphthalene (the predominant polynuclear compound in the ground water) and sodium (selected as a conservative tracer) range from about 20 mg/1 and 430 mg/1 in the aqueous phase at the source to about 2 mg/1 and 120 mg/1 at 430 m downgradient, respectively. Phenolic compounds and naphthalene are disappearing faster than expected if only dilution were occurring. Sorption of phenolic compounds on aquifer sediments is negligible but naphthalene is slightly sorbed. Anaerobic biodegradation of phenolic compounds is primarily responsible for the observed attenuation. Methane was found only in water samples from the contaminated zone (2-20 mg/1). Methane-producing bacteria were found only in water from the contaminated zone. Methane was produced in laboratory cultures of contaminated water inoculated with bacteria from the contaminated zone. Evidence for anaerobic biodegradation of naphthalene under either field or laboratory conditions was not obtained.
A Saint Louis encephalitis and Rocio virus serosurvey in Brazilian horses
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Jaqueline Raymondi Silva
2014-07-01
Full Text Available Introduction Arboviruses are an important public health problem in Brazil, in especially flaviviruses, including the Saint Louis encephalitis virus (SLEV and the Rocio virus (ROCV, are especially problematic. These viruses are transmitted to humans or other vertebrates through arthropod bites and may cause diseases with clinical manifestations that range from asymptomatic infection, viral hemorrhagic fever to encephalitis. Methods A serological survey of horses from various regions of Brazil using an enzyme-linked immunosorbent assay (ELISA with recombinant SLEV domain III peptides and ROCV E protein as antigens. Results Overall, 415 (55.1% of the 753 horses that were screened were seropositive for flavivirus and, among them, monotypic reactions were observed to SLEV in 93 (12.3% and to ROCV in 46 (6.1%. These results suggested that these viruses, or other closely related viruses, are infecting horses in Brazil. However, none of the studied horses presented central nervous system infection symptoms. Conclusions Our results suggest that SLEV and ROCV previously circulated among horses in northeast, west-central and southeast Brazil.
The renaissance of Peiresc: Aubin-Louis Millin and the postrevolutionary republic of letters.
Adkins, G Matthew
2008-12-01
This essay argues for the emergence of a cultural and epistemological divide between amateur savants and members of the Royal Academy of the Sciences in late Old Regime and revolutionary France and suggests that the amateur ideal rose in significance even as intellectual activity came to be increasingly centralized in the postrevolutionary era. At the crux of the tensions between the amateur ideal and the professionalizing reality in the immediate postrevolutionary period stood Aubin-Louis Millin and his journal, the Magasin Encyclopédique. The essay examines, in particular, the revival in the pages of the Magasin Encyclopédique of interest in Nicolas-Claude Fabri de Peiresc, the seventeenth-century icon of an amateur ideal in which investigations in the natural sciences and scholarship were private, decentralized, often provincial activities. Although the sciences in the revolutionary and Napoleonic eras were often perceived as forward looking and dismissive of the past, this essay finds that a sentimental and nostalgic attachment to the past-to a myth of Peiresc-continued to play an important role in the identity of postrevolutionary men of letters.
Making another world possible: the Torah, Louis Kelso, and the problem of poverty.
Greenfield, Sidney M
2007-01-01
Why is it that after centuries of concerted efforts to eliminate it, and decades of unprecedented economic growth that should have accomplished it, poverty not only is still with us but actually is increasing? Starting with a passage in the Old Testament, the source of moral behavior for believers of Judaism, Christianity, and Islam, this author argues that the postulation of the labor theory of value and scarcity by Adam Smith, and accepted as part of the basic framework of the discipline of economics, has prevented us from formulating public policies that would enable us to implement the way the God of the Abrahamic faiths intended the poor to be cared for. Substituting modifications in economic theory proposed originally by Louis Kelso, a model acknowledging the independent contribution of capital in the productive process is proposed that would enable us to formulate policies for the production and distribution of wealth and that would make the scourge of human poverty a bad dream of the past.
Molecular identification of Saint Louis encephalitis virus genotype IV in Colombia
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Richard Hoyos-López
2015-09-01
Full Text Available Saint Louis encephalitis virus (SLEV is a member of the Japanese-encephalitis virus serocomplex of the genus Flavivirus. SLEV is broadly distributed in the Americas and the Caribbean Islands, where it is usually transmitted by mosquitoes of the genus Culex and primarily to birds and mammalian-hosts. Humans are occasionally infected by the virus and are dead-end hosts. SLEV causes encephalitis in temperate regions, while in tropical regions of the Americas, several human cases and a wide biological diversity of SLEV-strains have been reported. The phylogenetic analysis of the envelope (E protein genes indicated eight-genotypes of SLEV with geographic overlap. The present paper describes the genotyping of two SLEV viruses detected in mosquito-pools collected in northern Colombia (department of Cordoba. We used reverse transcription-polymerase chain reaction to amplify a fragment of theE-gene to confirm the virus identity and completeE-gene sequencing for phylogenetic analysis and genotyping of the two-SLEV viruses found circulating in Córdoba. This is the first report of SLEV genotype IV in Colombia (Córdoba in mosquitoes from a region of human inhabitation, implicating the risk of human disease due to SLEV infection. Physicians should consider SLEV as a possible aetiology for undiagnosed febrile and neurologic syndromes among their patients who report exposure to mosquito-bites.
Microbiology of diabetic foot infections: from Louis Pasteur to 'crime scene investigation'.
Spichler, Anne; Hurwitz, Bonnie L; Armstrong, David G; Lipsky, Benjamin A
2015-01-07
Were he alive today, would Louis Pasteur still champion culture methods he pioneered over 150 years ago for identifying bacterial pathogens? Or, might he suggest that new molecular techniques may prove a better way forward for quickly detecting the true microbial diversity of wounds? As modern clinicians faced with treating complex patients with diabetic foot infections (DFI), should we still request venerated and familiar culture and sensitivity methods, or is it time to ask for newer molecular tests, such as 16S rRNA gene sequencing? Or, are molecular techniques as yet too experimental, non-specific and expensive for current clinical use? While molecular techniques help us to identify more microorganisms from a DFI, can they tell us 'who done it?', that is, which are the causative pathogens and which are merely colonizers? Furthermore, can molecular techniques provide clinically relevant, rapid information on the virulence of wound isolates and their antibiotic sensitivities? We herein review current knowledge on the microbiology of DFI, from standard culture methods to the current era of rapid and comprehensive 'crime scene investigation' (CSI) techniques.
Detection of Saint Louis encephalitis virus in dengue-suspected cases during a dengue 3 outbreak.
Terzian, Ana Carolina Bernardes; Mondini, Adriano; Bronzoni, Roberta Vieira de Moraes; Drumond, Betânia Paiva; Ferro, Bianca Piovezan; Cabrera, Eliana Márcia Sotello; Figueiredo, Luis Tadeu Moraes; Chiaravalloti-Neto, Francisco; Nogueira, Maurício Lacerda
2011-03-01
Arboviruses are frequently associated with outbreaks in humans and represent a serious public health problem. Among the Brazilian arboviruses, Mayaro virus, Dengue virus (DENV), Yellow Fever virus, Rocio virus, Saint Louis Encephalitis virus (SLEV), and Oropouche virus are responsible for most of human cases. All these arboviruses usually produce undistinguishable acute febrile illness, especially in the acute phase of infection. In this study we investigated the presence of arboviruses in sera of 519 patients presenting acute febrile illness, during a dengue outbreak in São José do Rio Preto City (São Paulo, Brazil). A multiplex-nested RT-polymerase chain reaction assay was applied to detect and identify the main Brazilian arboviruses (Flavivirus, Alphavirus, and Orthobunyavirus genera). The molecular analysis showed that 365 samples were positive to DENV-3, 5 to DENV-2, and 8 to SLEV. Among the positive samples, one coinfection was detected between DENV-2 and DENV-3. The phylogenetic analysis of the SLEV envelope gene indicated that the virus circulating in city is related to lineage V strains. These results indicated that during that large DENV-3 outbreak in 2006, different arboviruses cocirculated causing human disease. Thus, it is necessary to have an efficient surveillance system to control the dissemination of these arboviruses in the population.
[The life of doctor Louis-Désiré Véron (1798-1867)].
Planchon, Claude A
2004-06-01
The life of doctor Louis-Désiré Véron (1798-1867) was an incredible odyssey. Starting his professional life as an 'Interne des Hôpitaux de Paris', he found himself unable to enter the medical establishment at a time it was practically impossible to succeed in Parisian society without having being born into a wealthy family. He was eventually able to take his revenge on Paris when he had made a fortune from pharmacy. He became the head of the Le Pelletier Paris Opera (1831-1835), in one of the most brilliant periods of opera history, with productions of Robert le Diable by Meyerbeer and La Sylphide, a ballet choreographed by Filippo Taglioni. This latter was first interpreted by Marie, the prima ballerina daughter of Taglioni. Doctor Véron became her protector. He compensated for his ugly physical appearance by a combination of smart intelligence and a keen spirit, which enabled him to seduce Mademoiselle Rachel, one of the most famous tragic actresses of the era at La Comédie-Française.
Predictors of Size for Gestational Age in St. Louis City and County
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Pamela K. Xaverius
2014-01-01
Full Text Available Objective. To identify social, behavioral, and physiological risk factors associated with small for gestational age (SGA by gestational age category in St. Louis City and County. Methods. A retrospective cohort study was conducted using birth certificate and fetal death records from 2000 to 2009 (n = 142,017. Adjusted associations of risk factors with SGA were explored using bivariate logistic regression. Four separate multivariable logistic regression analyses, stratified by gestational age, were conducted to estimate adjusted odds ratios. Results. Preeclampsia and inadequate weight gain contributed significantly to increased odds for SGA across all gestational age categories. The point estimates ranged from a 3.41 increased odds among women with preeclampsia and 1.76 for women with inadequate weight gain at 24–28 weeks’ gestational age to 2.19 and 2.11 for full-term infants, respectively. Among full-term infants, smoking (aOR = 2.08, chronic hypertension (aOR = 1.46, and inadequate prenatal care (aOR = 1.25 had the next most robust and significant impact on SGA. Conclusion. Preeclampsia and inadequate weight gain are significant risk factors for SGA, regardless of gestational age. Education on the importance of nutrition and adequate weight gain during pregnancy is vital. In this community, disparities in SGA and smoking rates are important considerations for interventions designed to improve birth outcomes.
Science and the applications of science from Louis Pasteur to Jacques Monod.
Schwartz, Maxime
2015-06-01
Jacques Monod's ideas on the applications of science came within the scope of a long tradition at the Institut Pasteur. Louis Pasteur, whose scientific career was characterized by a permanent come and go between science and its applications, long opposed the idea of getting any income from his research, until the financial needs of the Institut Pasteur made him change his mind. As for Jacques Monod, he remained a fervent supporter of basic science during his whole scientific career. However, once he became director of the Institut Pasteur, he realized that the applications of research had to be developed to support the institute from a financial point of view. Thus, he reorganized the valorization of research in the institute, through an incitation of scientists to develop projects with possible applications, and by creating a company, Institut Pasteur Production, for which he had a factory built, and which was in charge of producing and commercializing the vaccines and reagents stemming from the research at the Institut Pasteur.
[Alain Georges: in the footsteps of Louis Pasteur and Eugène Jamot].
Bélec, L; Milleliri, J M
2014-01-01
The biography of the physician general Alain Jean Georges (1946-2012) shows the exceptional career of a military physician-clinical pathologist specialized in tropical medicine and educated at the Navy Health School in Bordeaux and the Pharo School in Marseille. He completed his education at the Institut Pasteur de Paris in courses still conducted in the spirit of those taught by Louis Pasteur. In 1979, he became director of the Pasteur Institute of Bangui, following in the steps of Eugène Jamot, in the long tradition of military doctors from the Institut Pasteur overseas network committed to a career in Africa. For more than 12 years, Alain Georges directed the Pasteur Institute of Bangui, one of the last citadels of French postcolonial military medicine, in a very personal and charismatic style. He was thus a pioneer in research about both AIDS in Africa and hemorrhagic fevers. His methods were widely misunderstood later as the traditional networks of French biomedical research in its former African colonies modernized and opened internationally, including to national elites. Alain Georges was probably one of the last important figures of the golden age of French colonial medicine.
Ciota, Alexander T; Koch, Evan M; Willsey, Graham G; Davis, Lauren J; Jerzak, Greta V S; Ehrbar, Dylan J; Wilke, Claus O; Kramer, Laura D
2011-03-01
St. Louis encephalitis virus (SLEV; Flaviviridae; Flavivirus) is a member of the Japanese encephalitis serocomplex and a close relative of West Nile virus (WNV). Although SLEV remains endemic to the US, both levels of activity and geographical dispersal are relatively constrained when compared to the widespread distribution of WNV. In recent years, WNV appears to have displaced SLEV in California, yet both viruses currently coexist in Texas and several other states. It has become clear that viral swarm characterization is required if we are to fully evaluate the relationship between viral genomes, viral evolution, and epidemiology. Mutant swarm size and composition may be particularly important for arboviruses, which require replication not only in diverse tissues but also divergent hosts. In order to evaluate temporal, spatial, and host-specific patterns in the SLEV mutant swarm, we determined the size, composition, and phylogeny of the intrahost swarm within primary mosquito isolates from both Texas and California. Results indicate a general trend of decreasing intrahost diversity over time in both locations, with recent isolates being highly genetically homogeneous. Additionally, phylogenic analyses provide detailed information on the relatedness of minority variants both within and among strains and demonstrate how both geographic isolation and seasonal maintenance have shaped the viral swarm. Overall, these data generally provide insight into how time, space, and unique transmission cycles influence the SLEV mutant swarm and how understanding these processes can ultimately lead to a better understanding of arbovirus evolution and epidemiology.
Seroconversion for West Nile and St. Louis encephalitis viruses among sentinel horses in Colombia.
Mattar, Salim; Komar, Nicholas; Young, Ginger; Alvarez, Jaime; Gonzalez, Marco
2011-12-01
We prospectively sampled flavivirus-naïve horses in northern Colombia to detect West Nile virus (WNV) and St. Louis encephalitis virus (SLEV) seroconversion events, which would indicate the current circulation of these viruses. Overall, 331 (34.1%) of the 971 horses screened were positive for past infection with flaviviruses upon initial sampling in July 2006. During the 12-month study from July 2006-June 2007, 33 WNV seroconversions and 14 SLEV seroconversions were detected, most of which occurred in the department of Bolivar. The seroconversion rates of horses in Bolivar for the period of March-June 2007 reached 12.4% for WNV and 6.7% for SLEV. These results comprise the first serologic evidence of SLEV circulation in Colombia. None of the horses sampled developed symptoms of encephalitis within three years of initial sampling. Using seroconversions in sentinel horses, we demonstrated an active circulation of WNV and SLEV in northern Colombia, particularly in the department of Bolivar. The absence of WNV-attributed equine or human disease in Colombia and elsewhere in the Caribbean Basin remains a topic of debate and speculation.
Molecular identification of Saint Louis encephalitis virus genotype IV in Colombia.
Hoyos-López, Richard; Soto, Sandra Uribe; Rúa-Uribe, Guillermo; Gallego-Gómez, Juan Carlos
2015-09-01
Saint Louis encephalitis virus (SLEV) is a member of the Japanese-encephalitis virus serocomplex of the genus Flavivirus. SLEV is broadly distributed in the Americas and the Caribbean Islands, where it is usually transmitted by mosquitoes of the genus Culex and primarily to birds and mammalian-hosts. Humans are occasionally infected by the virus and are dead-end hosts. SLEV causes encephalitis in temperate regions, while in tropical regions of the Americas, several human cases and a wide biological diversity of SLEV-strains have been reported. The phylogenetic analysis of the envelope (E) protein genes indicated eight-genotypes of SLEV with geographic overlap. The present paper describes the genotyping of two SLEV viruses detected in mosquito-pools collected in northern Colombia (department of Cordoba). We used reverse transcription-polymerase chain reaction to amplify a fragment of the E-gene to confirm the virus identity and complete E-gene sequencing for phylogenetic analysis and genotyping of the two-SLEV viruses found circulating in Córdoba. This is the first report of SLEV genotype IV in Colombia (Córdoba) in mosquitoes from a region of human inhabitation, implicating the risk of human disease due to SLEV infection. Physicians should consider SLEV as a possible aetiology for undiagnosed febrile and neurologic syndromes among their patients who report exposure to mosquito-bites.
Politica e censura nella Francia di Louis XIV: Chavigny de La Bretonnière
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Chiara Mainardi
2012-04-01
Full Text Available During the reign of Louis XIV French libertines were expressing their intellectual dissent by opposing absolutism and criticising historical and religious conflicts. While in France, before abrogating the Edict of Nantes, any opposition was suppressed, Chavigny de La Bretonnière supported a revolt against the Church and political power. The prominent role of clandestine literature in Old Regime France will be analysed in this paper by considering critical studies about libertinage. In particular, the political and antireligious discourse carried on by this author will be highlighted by taking into account his ‘lardons’, satirical articles against French government, his erotic novel La Religieuse en chemise and his ecclesiastic pamphlet Le Cochon mitré. In a true editorial campaign, Chavigny de La Bretonnière attaches French royal power, through the use of satire he depicts corrupted prelates as obscene creatures and he reforms libertine dialogue by enhancing broad political purposes. As a response to his critics and claims, Chavigny was kidnapped, tortured and imprisoned for life. His name disappeared from history.
Louis Massignon l'amour mystique ou l'extase dans l'abandon
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Jacques Keryell
2008-09-01
Full Text Available Parler de Massignon et de son Amour de Dieu n'est pas chose aisée. En effet, si les mystiques musulmans des premiers siècles de l'hégire ont été les hérauts de cet Amour : Al-Hallâj, Râbia al-Adawiyya, Al-Niffâri, Ibn Arabi, Ansâri, Al-Ghazâli, l'Amour de Dieu comme tel, n'est pas au cœur du "ilm al kalâm", de la théologie musulmane traditionnelle. Pour Massignon, langue et spiritualité étaient intimement liées. Si je devais me placer dans une perspective musulmane, je dirais que Louis Massignon se situe dans la ligne de la "wahdat al shuhûd", celle de "l'unicité du témoignage" ou Dieu se témoigne Lui-même en son mystère dans le cœur du soufi.
Genetic characterization of St. Louis encephalitis virus isolated from human in São Paulo, Brazil
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Cecília Luiza Simões dos Santos
2006-02-01
Full Text Available The molecular characterization of SPH253157, a new strain of St. Louis encephalitis virus (SLEV, isolated in 2004 from the first case of human infection recognized in the state of São Paulo, Brazil, is reported. The patient, presenting a febrile illness without neurological involvement, was hospitalized as a probable case of dengue fever. Genomic RNA was isolated from the supernatant of C6/36 cells infected with acute phase-serum specimen of the patient and the envelope gene was amplified by reverse-transcription-polymerase chain reaction. The complete nucleotide sequence of the envelope gene of this isolate was directly sequenced from the amplified products and compared with other Brazilian and American SLEV strains. Phylogenetic analyses were carried out under maximum likelihood criterion with outgroups both included and excluded. Outgroups comprised four flavivirus of the Japanese encephalitis group. Phylogeny also included Bayesian analysis. The results indicated that the new SLEV isolate belongs to lineage III, being closely related to an Argentinean strain recovered from Culex sp. in 1979. It is concluded that there are at least 3 lineages of SLEV in Brazil.
The Effects of NSTP on the Lives of Saint Louis University Students
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Marilyn L. Balmeo
2015-01-01
Full Text Available The National Service Training Program (NSTP of the Philippines is a form of service learning which is defined as the integration of community services to instruction in order to strengthen the civic and community responsibilities of the students. The purpose of this study is to determine the effectiveness of the NSTP for the students, its influences along self-improvement, performance, community involvement, and demonstration of abilities and skills, and the difficulties encountered by the students while enrolled in their respective NSTP courses. The 1421 respondents of the study were the undergraduate students of Saint Louis University who finished the NSTP courses last school year 2012-2013. The study utilized an adapted survey-type questionnaire to gather the data needed in the study. The findings of the study suggest that NSTP courses are effective and they influenced the self-improvement, performance, community involvement, and demonstration of abilities and skills of the students to an extent. The students are also able to continue to demonstrate the different competencies they learned or acquired from NSTP courses. Moreover, this study reveals that the students often encountered many difficulties while they were enrolled in the NSTP courses.
Hipp, J Aaron; Eyler, Amy A; Kuhlberg, Jill A
2013-12-01
Ciclovias are active street events when roads are open to walkers, cyclists, and families and closed to automobiles. Over 70 cities in the USA have implemented ciclovias to promote physical activity. The authors evaluated four events during 2010 to determine what activities participants perform and who is attending. For two ciclovia events in St. Louis, Missouri, observation reports of activities, gender, and age of 1,452 participants were collected, and 82 adults were interviewed via direct approach. The survey covered six domains: physical activity, travel to event, sense of community, marketing, economic impact, and demographics. Each event occurred within the city, along multiple streets. Domains were selected from Ciclovia Recreativa developed by Ciclovia Bogota, Pan American Health Organization, and CDC. Additional questions addressed city-specific goals and matched similar evaluations in other cities. Over 50 % of participants met CDC-defined weekly minute thresholds for physical activity. Participants, primarily (>80 %) middle class, college educated, and white, were not representative of the majority minority city population, which has high rates of poverty, and low percentage of college graduates. Cities must work with residents to increase low-income minority population participation in ciclovia-based physical activity.
Morphology of ruffe (Gymnocephalus cernuus) protolarvae from the St. Louis River, Lake Superior
French, John R. P.; Edsall, Thomas A.
1992-01-01
We describe hatching and the morphological and meristic characteristics of 2.5-5.6 mm long ruffe protolarvae (Gymnocephalus cernuus). Eggs and sperm from St. Louis River ruffe were mixed, producing fertilized eggs that were 0.9-1.2 mm in diameter. Newly hatched protolarvae were 2.5-3.2 mm long. They had 14-15 preanal and 23-24 postanal myomeres, a continuous finfold of even width, unpigmented eyes, and a large anterior oil globule in the yolk sac, and the head deflected over the yolk sac. Pectoral fin buds appeared on the dorsal side of the yolk sac 5 hours after hatching. Two-day-old protolarvae had fully pigmented eyes, and the head was free from the yolk sac. Three-day-old protolarvae were 3.9-4.3 mm long and possessed opercula, gills, pectoral fins, and a functional jaw. Feeding and swimming began about one week after hatching when the yolk sac was almost completely absorbed. Protolarvae grew rapidly at 20-22 degrees C and were 4.9-5.6 mm long after 13 days. Newly hatched ruffe protolarvae are distinguished from other Lake Superior percids by having the fewest preanal myomeres (14-15), the head deflected over the yolk sac, continuous finfold of even width, and a total length of less than 4.0 mm.
Seroconversion for west Nile and St. Louis encephalitis viruses among sentinel horses in Colombia
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Salim Mattar
2011-12-01
Full Text Available We prospectively sampled flavivirus-naïve horses in northern Colombia to detect West Nile virus (WNV and St. Louis encephalitis virus (SLEV seroconversion events, which would indicate the current circulation of these viruses. Overall, 331 (34.1% of the 971 horses screened were positive for past infection with flaviviruses upon initial sampling in July 2006. During the 12-month study from July 2006-June 2007, 33 WNV seroconversions and 14 SLEV seroconversions were detected, most of which occurred in the department of Bolivar. The seroconversion rates of horses in Bolivar for the period of March-June 2007 reached 12.4% for WNV and 6.7% for SLEV. These results comprise the first serologic evidence of SLEV circulation in Colombia. None of the horses sampled developed symptoms of encephalitis within three years of initial sampling. Using seroconversions in sentinel horses, we demonstrated an active circulation of WNV and SLEV in northern Colombia, particularly in the department of Bolivar. The absence of WNV-attributed equine or human disease in Colombia and elsewhere in the Caribbean Basin remains a topic of debate and speculation.
[Malaria and the work of two writer-physicians: Louis Ferdinand Celine and Carlo Levi].
Theodorides, J
1999-01-01
Malaria rarely mentioned in literary works has been dealt with by the two writers, both physicians, studied here. Louis-Ferdinand Destouches (1894-1961) alias Celine, studied medicine in Rennes and Paris from 1921 to 1924. He had been previously engaged by the Rockefeller Foundation to lecture on tuberculosis in Brittany. He later worked for the Commission of Hygiene of the League of Nations in Geneva and took part in 1925 to a long voyage in America (Cuba, United States) and Italy where malaria was still occurring. In 1926 he published a book: La quinine en therapeutique and participated to another voyage in West Africa where he contracted malaria. Numerous hints to this disease inspired to Celine by his first trip to Africa (Cameroun) in 1916-17 are found in Voyage au bout de la nuit (1932). Carlo Levi (1902-1975) studied medicine in Torino from 1919 to 1924. Painter and writer he wrote there his masterpiece: Christ has stopped in Eboli (1945). Malaria which then decimated a very poor population of peasants abandoned to themselves represents the background of the book and it is as a competent and human physician that C. Levi gained the friendship of the inhabitants of this remote and inhospitable province.
Herold, Elisabeth; Strauch, Matthias; Michalik, Dirk; Appelhagen, Andreas; Ludwig, Ralf
2014-10-06
The validity of Stokes-Einstein (SE) and Stokes-Einstein-Debye (SED) relations for methanol in the physical environment of the ionic liquid (IL) 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide is studied by means of nuclear magnetic resonance (NMR) relaxation time experiments, viscosity measurements and molecular dynamics (MD) simulations. The reorientational correlation times of the hydroxyl groups of pure methanol and of methanol in the IL/methanol mixtures were determined. For that purpose an approach for estimating NMR deuteron quadrupole coupling constants, presented by Wendt and Farrar (Mol. Phys. 1998, 95, 1077-1081), was confirmed. The self-diffusion coefficients of methanol were taken from the MD simulations. The viscosities of all systems were then measured and the SE and SED relations validated. For pure methanol both relations are valid, whereas they become increasingly invalid with increasing IL concentration, as indicated by effective volumes and radii that are too low. The deviation from the SE and SED relations could be related to dynamical heterogeneities described by the non-Gaussian parameter α(t) obtained from MD simulations. For pure methanol, α(t) is close to zero in accord with the validity of both relations. With increasing IL concentration the dynamical heterogeneities of methanol increase strongly. The times t* at the maximum of α(t) increase linearly with the relative number of methanol monomers in the mixtures. Thus, the dynamical heterogeneities are largest for single methanol molecules fully embedded in the IL environment. In their own environment methanol molecules are highly mobile, whereas in the IL-rich region the mobility is strongly reduced leading to the non-validity of SE and SED relations.
Mathematical analysis of the Navier-Stokes equations with non standard boundary conditions
Tidriri, M. D.
1995-01-01
One of the major applications of the domain decomposition time marching algorithm is the coupling of the Navier-Stokes systems with Boltzmann equations in order to compute transitional flows. Another important application is the coupling of a global Navier-Stokes problem with a local one in order to use different modelizations and/or discretizations. Both of these applications involve a global Navier-Stokes system with nonstandard boundary conditions. The purpose of this work is to prove, using the classical Leray-Schauder theory, that these boundary conditions are admissible and lead to a well posed problem.
Resurgence, Stokes phenomenon and alien derivatives for level-one linear differential systems
Loday-Richaud, Michèle; Remy, Pascal
A precise description of the singularities of the Borel transform of solutions of a level-one linear differential system is deduced from a proof of the summable-resurgence of the solutions by the perturbative method of J. Écalle. Then we compare the meromorphic classification (Stokes phenomenon) from the viewpoint of the Stokes cocycle and the viewpoint of alien derivatives. We make explicit the Stokes-Ramis matrices as functions of the connection constants in the Borel plane and we develop two examples. No assumption of genericity is made.
Resurgence, Stokes phenomenon and alien derivatives for level-one linear differential systems
Loday-Richaud, Michèle
2010-01-01
A precise description of the singularities of the Borel transform of solutions of a level-one linear differential system is deduced from a proof of the summable-resurgence of the solutions by the perturbative method of J. \\'Ecalle. Then we compare the meromorphic classification (Stokes phenomenon) from the viewpoint of the Stokes cocycle and the viewpoint of alien derivatives. We make explicit the Stokes-Ramis matrices as functions of the connection constants in the Borel plane and we develop two examples. No assumption of genericity is made.
Competition between two types of anti-Stokes emission in Ho(3+)-activated ZBLAN glass.
Koepke, Cz; Wisniewski, K; Piatkowski, D; Malinowski, M
2009-01-21
A competition between two anti-Stokes emissions has been observed and interpreted in ZBLAN glass activated by Ho(3+) ions. The first anti-Stokes emission intensity was seen to increase with temperature, whereas another, upconverted emission, was seen to decrease under the same conditions. Both observed tendencies are believed to be caused by the same effect: the multiphonon anti-Stokes excitation of the state responsible for the first emission. Analysis of the kinetics and fits of the theoretical model to experimental data are presented.
Competition between two types of anti-Stokes emission in Ho3+-activated ZBLAN glass
Koepke, Cz; Wisniewski, K.; Piatkowski, D.; Malinowski, M.
2009-01-01
A competition between two anti-Stokes emissions has been observed and interpreted in ZBLAN glass activated by Ho3+ ions. The first anti-Stokes emission intensity was seen to increase with temperature, whereas another, upconverted emission, was seen to decrease under the same conditions. Both observed tendencies are believed to be caused by the same effect: the multiphonon anti-Stokes excitation of the state responsible for the first emission. Analysis of the kinetics and fits of the theoretical model to experimental data are presented.
A rigorous justification of the Euler and Navier-Stokes equations with geometric effects
Bella, Peter; Lewicka, Marta; Novotny, Antonin
2015-01-01
We derive the 1D isentropic Euler and Navier-Stokes equations describing the motion of a gas through a nozzle of variable cross section as the asymptotic limit of the 3D isentropic Navier-Stokes system in a cylinder, the diameter of which tends to zero. Our method is based on the relative energy inequality satisfied by any weak solution of the 3D Navier-Stokes system and a variant of Korn-Poincare's inequality on thin channels that may be of independent interest.
NAJAFİ, Ghader
2012-01-01
Araştırma Iran’ın Miandoab ilçesi bünyesinde olan “Ghezel ırkı koyun ıslah ve yetiştirme merkezi’nde” bulunan 257 baş Ghezel ırkı koyununda ve normal aşım mevsiminde yürütülmüştür. Çalışmada, normal aşım döneminde CIDR (Kontrollü Progesteron Salıcı Alet) ile senkronize edilen Ghezel ırkı koyunlarda döl verimi üzerine PMSG’nin farklı dozları ve suni tohumlama tekniklerinin etkilerinin tesbit edilmesi amaçlanmıştır. Çalışmada yer alan koyunlara 14 gün sür...
Tricontinental Routes of Solidarity: Stokely Carmichael in Cuba
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Sarah Seidman
2012-12-01
Full Text Available Stokely Carmichael’s visit to Cuba for three weeks in the summer of 1967 illustrates a convergence in the transnational routes of the African American freedom struggle and the Cuban Revolution. African American activists saw Cuba as a model for resisting US power, eradicating racism, and enacting societal change, while the Cuban government considered African Americans allies against US imperialism and advocates of Cuba’s antiracist stance. Amidst racial violence in the United States and Cuba’s efforts to inspire revolution, Carmichael’s presence at the Organization of Latin American Solidarity conference in Havana—and in particular his interactions with Fidel Castro—caused ripples worldwide. A shared “tricontinental” vision that promoted unity in the Global South against imperialism, capitalism, and racism facilitated Carmichael’s solidarity with Castro. Yet divergent views on the role of race in fighting oppression limited their solidarity. Carmichael and Castro’s spectacular alliance demonstrated their personal affinity and ideological commonalities but did not result in an institutional alliance between the black liberation movement and the Cuban state. Instead Carmichael’s connection with the Cuban Revolution left an underexplored legacy. Examining Carmichael’s visit to Cuba illustrates the possibilities and pitfalls of transnational solidarity and furthers our understanding of postwar struggles for change.
Medical image of the week: Cheyne Stokes breathing on polysomnography
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Le T
2016-04-01
Full Text Available No abstract available. Article truncated at 150 words. A 79-year-old man presented to the sleep lab for a split-night polysomnography (PSG after a positive Berlin Questionnaire. He was screened and directly referred to our sleep lab through his PCP. Patient has a chart documented medical history of atrial fibrillation, idiopathic pulmonary fibrosis, obesity, and CHF. He did not have an echocardiogram available therefore the etiology of his CHF was unclear. He was found to have severe obstructive sleep apnea and was split early in the night. Prior to positive airway pressure, his apnea-hypopnea index (AHI was 77 and were predominantly obstructive hypopneas. Soon after initiation of positive airway pressure, his PSG revealed the breathing pattern seen in Figure 1. His respirations exhibited a crescendo-decrescendo pattern (arrow followed by a period of central apnea consistent with Cheyne Stokes breathing (CSB. In this patient, CSB was likely due to heart failure, although systolic or diastolic remained unclear. Of note, he ...
Hydrodynamics beyond Navier-Stokes: the slip flow model.
Yudistiawan, Wahyu P; Ansumali, Santosh; Karlin, Iliya V
2008-07-01
Recently, analytical solutions for the nonlinear Couette flow demonstrated the relevance of the lattice Boltzmann (LB) models to hydrodynamics beyond the continuum limit [S. Ansumali, Phys. Rev. Lett. 98, 124502 (2007)]. In this paper, we present a systematic study of the simplest LB kinetic equation-the nine-bit model in two dimensions--in order to quantify it as a slip flow approximation. Details of the aforementioned analytical solution are presented, and results are extended to include a general shear- and force-driven unidirectional flow in confined geometry. Exact solutions for the velocity, as well as for pertinent higher-order moments of the distribution functions, are obtained in both Couette and Poiseuille steady-state flows for all values of rarefaction parameter (Knudsen number). Results are compared with the slip flow solution by Cercignani, and a good quantitative agreement is found for both flow situations. Thus, the standard nine-bit LB model is characterized as a valid and self-consistent slip flow model for simulations beyond the Navier-Stokes approximation.
Coherent anti-Stokes Raman scattering under electric field stimulation
Capitaine, Erwan; Ould Moussa, Nawel; Louot, Christophe; Lefort, Claire; Pagnoux, Dominique; Duclère, Jean-René; Kaneyasu, Junya F.; Kano, Hideaki; Duponchel, Ludovic; Couderc, Vincent; Leproux, Philippe
2016-12-01
We introduce an experiment using electro-CARS, an electro-optical method based on the combination of ultrabroadband multiplex coherent anti-Stokes Raman scattering (M-CARS) spectroscopy and electric field stimulation. We demonstrate that this method can effectively discriminate the resonant CARS signal from the nonresonant background owing to a phenomenon of molecular orientation in the sample medium. Such molecular orientation is intrinsically related to the induction of an electric dipole moment by the applied static electric field. Evidence of the electro-CARS effect is obtained with a solution of n -alkanes (CnH2 n +2 , 15 ≤n ≤40 ), for which an enhancement of the CARS signal-to-noise ratio is achieved in the case of CH2 and CH3 symmetric/asymmetric stretching vibrations. Additionally, an electric-field-induced second-harmonic generation experiment is performed in order to corroborate the orientational organization of molecules due to the electric field excitation. Finally, we use a simple mathematical approach to compare the vibrational information extracted from electro-CARS measurements with spontaneous Raman data and to highlight the impact of electric stimulation on the vibrational signal.
The Stokes boundary layer for a thixotropic or antithixotropic fluid
McArdle, Catriona R.
2012-10-01
We present a mathematical investigation of the oscillatory boundary layer in a semi-infinite fluid bounded by an oscillating wall (the so-called \\'Stokes problem\\'), when the fluid has a thixotropic or antithixotropic rheology. We obtain asymptotic solutions in the limit of small-amplitude oscillations, and we use numerical integration to validate the asymptotic solutions and to explore the behaviour of the system for larger-amplitude oscillations. The solutions that we obtain differ significantly from the classical solution for a Newtonian fluid. In particular, for antithixotropic fluids the velocity reaches zero at a finite distance from the wall, in contrast to the exponential decay for a thixotropic or a Newtonian fluid.For small amplitudes of oscillation, three regimes of behaviour are possible: the structure parameter may take values defined instantaneously by the shear rate, or by a long-term average; or it may behave hysteretically. The regime boundaries depend on the precise specification of structure build-up and breakdown rates in the rheological model, illustrating the subtleties of complex fluid models in non-rheometric settings. For larger amplitudes of oscillation the dominant behaviour is hysteretic. We discuss in particular the relationship between the shear stress and the shear rate at the oscillating wall. © 2012 Elsevier B.V.
Stokes-vector direct detection for optical communications
Shieh, William; Li, An; Che, Di; Yuan, Feng; Khodakarami, Hamid
2017-01-01
To cope with the exponential growth of the Internet traffic, optical communications has advanced by leaps and bounds. For several decades, Intensity modulation with direct detection (IM-DD) dominates the commercial short-reach optical communications. However, when upgrading the data-rate distance product to 1000 Gb/s·km per wavelength and beyond, IM-DD faces severe performance barrier. Aiming to improve the electrical SE and extend the transmission distance, advanced DD modulation formats have been proposed through a so-called self-coherent (SCOH) approach, where a carrier is transmitted together with the signal to achieve a linear mapping between the electrical baseband signal and the optical field. In that way, the impact of the CD can be removed from the received signal, greatly extending the transmission distance of the DD system. Particularly, Stokes-vector direct detection (SV-DD) has been proposed to realize linear complex optical channels as well as enhance the electrical spectral efficiency and transmission reach. In this talk, we present the principle and discuss the performance of SV-DD systems.
ANALYTICAL CALCULATION OF STOKES PROFILES OF ROTATING STELLAR MAGNETIC DIPOLE
Energy Technology Data Exchange (ETDEWEB)
Martinez Gonzalez, M. J. [Instituto de Astrofisica de Canarias, Via Lactea s/n, 38200 La Laguna, Tenerife (Spain); Asensio Ramos, A. [Departamento de Astrofisica, Universidad de La Laguna, E-38205 La Laguna, Tenerife (Spain)
2012-08-20
The observation of the polarization emerging from a rotating star at different phases opens up the possibility to map the magnetic field in the stellar surface thanks to the well-known Zeeman-Doppler imaging. When the magnetic field is sufficiently weak, the circular and linear polarization profiles locally in each point of the star are proportional to the first and second derivatives of the unperturbed intensity profile, respectively. We show that the weak-field approximation (for weak lines in the case of linear polarization) can be generalized to the case of a rotating star including the Doppler effect and taking into account the integration on the stellar surface. The Stokes profiles are written as a linear combination of wavelength-dependent terms expressed as series expansions in terms of Hermite polynomials. These terms contain the surface-integrated magnetic field and velocity components. The direct numerical evaluation of these quantities is limited to rotation velocities not larger than eight times the Doppler width of the local absorption profiles. Additionally, we demonstrate that in a rotating star, the circular polarization flux depends on the derivative of the intensity flux with respect to the wavelength and also on the profile itself. Likewise, the linear polarization depends on the profile and on its first and second derivatives with respect to the wavelength. We particularize the general expressions to a rotating dipole.
Stability of Filters for the Navier-Stokes Equation
Brett, C E A; Law, K J H; McCormick, D S; Scott, M R; Stuart, A M
2011-01-01
Data assimilation methodologies are designed to incorporate noisy observations of a physical system into an underlying model in order to infer the properties of the state of the system. Filters refer to a class of data assimilation algorithms designed to update the estimation of the state in a on-line fashion, as data is acquired sequentially. For linear problems subject to Gaussian noise filtering can be performed exactly using the Kalman filter. For nonlinear systems it can be approximated in a systematic way by particle filters. However in high dimensions these particle filtering methods can break down. Hence, for the large nonlinear systems arising in applications such as weather forecasting, various ad hoc filters are used, mostly based on making Gaussian approximations. The purpose of this work is to study the properties of these ad hoc filters, working in the context of the 2D incompressible Navier-Stokes equation. By working in this infinite dimensional setting we provide an analysis which is useful f...
The mixed finite element multigrid method for stokes equations.
Muzhinji, K; Shateyi, S; Motsa, S S
2015-01-01
The stable finite element discretization of the Stokes problem produces a symmetric indefinite system of linear algebraic equations. A variety of iterative solvers have been proposed for such systems in an attempt to construct efficient, fast, and robust solution techniques. This paper investigates one of such iterative solvers, the geometric multigrid solver, to find the approximate solution of the indefinite systems. The main ingredient of the multigrid method is the choice of an appropriate smoothing strategy. This study considers the application of different smoothers and compares their effects in the overall performance of the multigrid solver. We study the multigrid method with the following smoothers: distributed Gauss Seidel, inexact Uzawa, preconditioned MINRES, and Braess-Sarazin type smoothers. A comparative study of the smoothers shows that the Braess-Sarazin smoothers enhance good performance of the multigrid method. We study the problem in a two-dimensional domain using stable Hood-Taylor Q2-Q1 pair of finite rectangular elements. We also give the main theoretical convergence results. We present the numerical results to demonstrate the efficiency and robustness of the multigrid method and confirm the theoretical results.
Disentangling the triadic interactions in Navier-Stokes equations
Sahoo, Ganapati
2015-01-01
We study the role of helicity in the dynamics of energy transfer in a modified version of the Navier-Stokes equations with explicit breaking of the mirror symmetry. We select different set of triads participating in the dynamics on the basis of their helicity content. In particular, we remove the negative helically polarized Fourier modes at all wavenumbers except for those falling on a localized shell of wavenumber, $|{\\bf k}| \\sim k_m$. Changing $k_m$ to be above or below the forcing scale, $k_f$, we are able to assess the energy transfer of triads belonging to different interaction classes. We observe that when the negative helical modes are present only at wavenumber smaller than the forced wavenumbers, an inverse energy cascade develops with an accumulation of energy on a stationary helical condensate. Vice versa, when negative helical modes are present only at wavenumber larger than the forced wavenumbers, a transition from backward to forward energy transfer is observed in the regime when the minority ...
Propulsion of micro-structures in Oscillatory Stokes Flow
Jo, Ikhee; Huang, Yangyang; Zimmerman, Walter; Kanso, Eva
2015-11-01
Drug delivery often necessitates specific site-targeting within the human body. The use of micro and/or nano devices swimming through the bloodstream provides an attractive mechanism for targeted drug targeting, however the design and practical implementation of such devices remain very challenging. Inspired by flapping wings, we construct a two-dimensional wedge-like device, consisting of two links connected by a linear torsional spring and released in an oscillatory Stokes flow. We vary the stiffness and rest angle of the linear spring and the oscillation amplitude and frequency of the background flow to explore the behavior of the device. We find that the device achieves a net displacement, or propulsion, in oscillatory flows even when no elastic energy is stored initially, thus breaking Purcell's scallop's theorem. More importantly, the vehicle tends to align with the background flow under perturbations. We conclude by commenting on how to control the parameters of the device and the fluid to achieve desired behavior of the device. These findings may have significant implications on the design of micro devices in viscous fluids.
The Navier-Stokes equations an elementary functional analytic approach
Sohr, Hermann
2001-01-01
The primary objective of this monograph is to develop an elementary and self contained approach to the mathematical theory of a viscous incompressible fluid in a domain 0 of the Euclidean space ]Rn, described by the equations of Navier Stokes. The book is mainly directed to students familiar with basic functional analytic tools in Hilbert and Banach spaces. However, for readers' convenience, in the first two chapters we collect without proof some fundamental properties of Sobolev spaces, distributions, operators, etc. Another important objective is to formulate the theory for a completely general domain O. In particular, the theory applies to arbitrary unbounded, non-smooth domains. For this reason, in the nonlinear case, we have to restrict ourselves to space dimensions n = 2,3 that are also most significant from the physical point of view. For mathematical generality, we will develop the lin earized theory for all n 2 2. Although the functional-analytic approach developed here is, in principle, known ...
SAINT LOUIS ENCEPHALITIS VIRUS IN MATO GROSSO, CENTRAL-WESTERN BRAZIL
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Letícia Borges da Silva HEINEN
2015-06-01
Full Text Available The dengue virus (DENV, which is frequently involved in large epidemics, and the yellow fever virus (YFV, which is responsible for sporadic sylvatic outbreaks, are considered the most important flaviviruses circulating in Brazil. Because of that, laboratorial diagnosis of acute undifferentiated febrile illness during epidemic periods is frequently directed towards these viruses, which may eventually hinder the detection of other circulating flaviviruses, including the Saint Louis encephalitis virus (SLEV, which is widely dispersed across the Americas. The aim of this study was to conduct a molecular investigation of 11 flaviviruses using 604 serum samples obtained from patients during a large dengue fever outbreak in the state of Mato Grosso (MT between 2011 and 2012. Simultaneously, 3,433 female Culex spp. collected with Nasci aspirators in the city of Cuiabá, MT, in 2013, and allocated to 409 pools containing 1-10 mosquitoes, were also tested by multiplex semi-nested reverse transcription PCR for the same flaviviruses. SLEV was detected in three patients co-infected with DENV-4 from the cities of Cuiabá and Várzea Grande. One of them was a triple co-infection with DENV-1. None of them mentioned recent travel or access to sylvatic/rural regions, indicating that transmission might have occurred within the metropolitan area. Regarding mosquito samples, one pool containing one Culex quinquefasciatus female was positive for SLEV, with a minimum infection rate (MIR of 0.29 per 1000 specimens of this species. Phylogenetic analysis indicates both human and mosquito SLEV cluster, with isolates from genotype V-A obtained from animals in the Amazon region, in the state of Pará. This is the first report of SLEV molecular identification in MT.
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Luis Adrian Díaz
2012-01-01
Full Text Available St. Louis encephalitis virus is a complex zoonoses. In 2005, 47 laboratory-confirmed and probable clinical cases of SLEV infection were reported in Córdoba, Argentina. Although the causes of 2005 outbreak remain unknown, they might be related not only to virological factors, but also to ecological and environmental conditions. We hypothesized that one of the factors for SLE reemergence in Córdoba, Argentina, was the introduction of a new SLEV genotype (SLEV genotype III, with no previous activity in the area. In order to evaluate this hypothesis we carried out a molecular characterization of SLEV detections from mosquitoes collected between 2001 and 2004 in Córdoba city. A total of 315 mosquito pools (11,002 individuals including 12 mosquitoes species were analyzed. Overall, 20 pools (8 mosquitoes species were positive for SLEV. During this study, genotypes II, V and VII were detected. No mosquito pool infected with genotype III was detected before the 2005 outbreak. Genotype V was found every year and in the 8 sampled sites. Genotypes II and VII showed limited temporal and spatial activities. We cannot dismiss the association of genotype II and V as etiological agents during the outbreak. However, the silent circulation of other SLEV strains in Córdoba city before the 2005 outbreak suggests that the introduction of genotype III was an important factor associated to this event. Not mutually exclusive, other factors such as changes in avian hosts and mosquitoes vectors communities, driven by climatic and environmental modifications, should also be taken into consideration in further studies.
Geostatistical three-dimensional modeling of oolite shoals, St. Louis Limestone, southwest Kansas
Qi, L.; Carr, T.R.; Goldstein, R.H.
2007-01-01
In the Hugoton embayment of southwestern Kansas, reservoirs composed of relatively thin (oil. The geometry and distribution of oolitic deposits control the heterogeneity of the reservoirs, resulting in exploration challenges and relatively low recovery. Geostatistical three-dimensional (3-D) models were constructed to quantify the geometry and spatial distribution of oolitic reservoirs, and the continuity of flow units within Big Bow and Sand Arroyo Creek fields. Lithofacies in uncored wells were predicted from digital logs using a neural network. The tilting effect from the Laramide orogeny was removed to construct restored structural surfaces at the time of deposition. Well data and structural maps were integrated to build 3-D models of oolitic reservoirs using stochastic simulations with geometry data. Three-dimensional models provide insights into the distribution, the external and internal geometry of oolitic deposits, and the sedimentologic processes that generated reservoir intervals. The structural highs and general structural trend had a significant impact on the distribution and orientation of the oolitic complexes. The depositional pattern and connectivity analysis suggest an overall aggradation of shallow-marine deposits during pulses of relative sea level rise followed by deepening near the top of the St. Louis Limestone. Cemented oolitic deposits were modeled as barriers and baffles and tend to concentrate at the edge of oolitic complexes. Spatial distribution of porous oolitic deposits controls the internal geometry of rock properties. Integrated geostatistical modeling methods can be applicable to other complex carbonate or siliciclastic reservoirs in shallow-marine settings. Copyright ?? 2007. The American Association of Petroleum Geologists. All rights reserved.
Blazer, V.S.; Hoffman, J.; Walsh, H.L.; Braham, R.P.; Hahn, C.; Collins, P.; Jorgenson, Z.; Ledder, T.
2014-01-01
In Spring 2011, 200 adult white sucker were collected in four areas of the St. Louis River area of concern (AOC), located in Minnesota and Wisconsin, USA. The areas included the upper AOC as a reference area, the upper estuary, St. Louis Bay and Superior Bay. Grossly visible abnormalities were documented and preserved for microscopic analyses, as were five to eight representative pieces of liver tissue. A piece of dorsal muscle was preserved for stable isotope analyses and otoliths removed for age determination. The incidence of raised skin lesions (mucoid plaques) was high (31 %), however, microscopically only 4.5 % of the white suckers had neoplasia (papillomas). The remaining lesions were epidermal hyperplasia. Superior Bay had the lowest percentage of skin/lip lesions (10 %), while St. Louis Bay had the highest (44 %). St. Louis Bay also had the highest incidence of skin neoplasms (12 %). No hepatocellular neoplasms were documented, however bile duct tumors were observed in 4.5 % of the suckers. Foci of cellular alteration were observed in fish from all sites except the upper AOC. Stable isotope data indicated that most of the suckers relied on the St. Louis River AOC for the majority (>75 %) of their diet, indicating they were resident within the AOC and not in Lake Superior. The amount of diet obtained from the upper estuary was a significant predictor of skin lesion incidence. Hence, habitat use within the AOC appears to be an important risk factor for skin and possibly, liver lesions.
Bito, Kotatsu; Okuno, Masanari; Kano, Hideaki; Leproux, Philippe; Couderc, Vincent; Hamaguchi, Hiro-o.
2013-06-01
We have developed a three-pulse non-degenerate multiplex coherent Raman microspectroscopic system using a white-light laser source. The fundamental output (1064 nm) of a Nd:YAG laser is used for the pump radiation with the white-light laser output (1100-1700 nm) for the Stokes radiation to achieve broadband multiplex excitations of vibrational coherences. The second harmonic (532 nm) of the same Nd:YAG laser is used for the probe radiation. Thanks to the large wavelength difference between the pump and probe radiations, coherent anti-Stokes Raman scattering (CARS) and coherent Stokes Raman scattering (CSRS) can be detected simultaneously. Simultaneous detection of CARS and CSRS enables us to obtain information on the electronic resonance effect that affects differently the CARS and CSRS signals. Simultaneous analysis of the CARS and CSRS signals provides us the imaginary part of χ(3) without introducing any arbitrary parameter in the maximum entropy method (MEM).
Semi-Group Theory for the Stokes Operator with Navier-Type Boundary Conditions on L p -Spaces
Al Baba, Hind; Amrouche, Chérif; Escobedo, Miguel
2017-02-01
In this article we consider the Stokes problem with Navier-type boundary conditions on a domain {Ω}, not necessarily simply connected. Since, under these conditions, the Stokes problem has a non trivial kernel, we also study the solutions lying in the orthogonal of that kernel. We prove the analyticity of several semigroups generated by the Stokes operator considered in different functional spaces. We obtain strong, weak and very weak solutions for the time dependent Stokes problem with the Navier-type boundary condition under different hypotheses on the initial data u 0 and external force f. Then, we study the fractional and pure imaginary powers of several operators related with our Stokes operators. Using the fractional powers, we prove maximal regularity results for the homogeneous Stokes problem. On the other hand, using the boundedness of the pure imaginary powers, we deduce maximal {Lp-Lq} regularity for the inhomogeneous Stokes problem.
Institute of Scientific and Technical Information of China (English)
罗振东; 朱江
2002-01-01
Two simplified and stabilized mixed element formats for the Stokes problem are derived by bubble function, and their convergence,i.e,error analysis, are proved.These formats can save more freedom degrees than other usual formats.
Generation of Anti-Stokes Line in Fundamental Mode of Photonic Crystal Fibre
Institute of Scientific and Technical Information of China (English)
WANG Wei; HOU Lan-Tian; LIU Zhao-Lun; ZHOU Gui-Yao
2008-01-01
A photonic crystal fibre (PCF) with zero-dispersion wavelength around 800 nm is designed and fabricated. Simulated results show that the zero-dispersion wavelength of fundamental mode for this PCF is at 826 nm, and phase-matched four-wave mixing can be achieved in fundamental mode. Using 20Ofs Ti:sapphire laser with central wavelength at 810nm as pump, the anti-Stokes line around 610nm is generated efficiently. The output signal has a Gaussian-like profile, which indicates that the anti-Stokes signal is in the fundamental mode of the PCF. The energy of anti-Stokes signal is higher than that of residual pump laser and the maximum ratio of the anti-Stokes signal to the pump component in the output spectrum is estimated to be 1.2.
PARTIAL REGULARITY FOR WEAK SOLUTIONS OF STATIONARY NAVIER-STOKES SYSTEMS
Institute of Scientific and Technical Information of China (English)
Chen Shuhong; Tan Zhong
2008-01-01
This article is concerned with the partial regularity for the weak solutions of stationary Navier-Stokes system under the controllable growth condition. By A-harmonic approximation technique, the optimal regularity is obtained.
Symplectic Exact Solution for Stokes Flow in the Thin Film Coating Applications
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Yan Wang
2014-01-01
Full Text Available The symplectic analytical method is introduced to solve the problem of the stokes flow in the thin film coating applications. Based on the variational principle, the Lagrangian function of the stokes flow is established. By using the Legendre transformation, the dual variables of velocities and the Hamiltonian function are derived. Considering velocities and stresses as the basic variables, the equations of stokes flow problems are transformed into Hamiltonian system. The method of separation of variables and expansion of eigenfunctions are developed to solve the governing equations in Hamiltonian system, and the analytical solutions of the stokes flow are obtained. Several numerical simulations are carried out to verify the analytical solutions in the present study and discuss the effects of the driven lids of the square cavity on the dynamic behavior of the flow structure.