WorldWideScience

Sample records for abbot prism chagas

  1. James Abbot McNeill Whistler: "At the Piano."

    Science.gov (United States)

    Hallenberg, Heather

    1987-01-01

    "At the Piano," an oil-on-canvas painting completed in 1859 by James Abbot McNeill Whistler, is used as the basis of a lesson designed to help junior high school students analyze the painting's mood, subject matter, and composition. (JDH)

  2. Chagas Disease

    Science.gov (United States)

    Chagas disease is caused by a parasite. It is common in Latin America but not in the United States. ... nose, the bite wound or a cut. The disease can also spread through contaminated food, a blood ...

  3. Australopithecine enamel prism patterns.

    Science.gov (United States)

    Vrba, E S; Grine, F E

    1978-11-24

    Following a recent suggestion that tooth enamel prism shape differs within Hominoidea, the teeth of a number of extinct and extant hominoid species were analyzed by scanning electron microscopy. The enamel prism patterns of some gracile and robust australopithecine specimens from Sterkfontein, Swartkrans, and Kromdraai are recorded. The characteristic arrangements of enamel prisms in all modern and extinct hominoid species were found to be essentially similar. The implications of enamel prisms for phylogenetic deduction in Hominoidea are discussed. PMID:102032

  4. Treatment of Chagas Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Fernando A. Botoni

    2013-01-01

    Full Text Available Chagas' disease (ChD, caused by the protozoa Trypanosoma cruzi (T. cruzi, was discovered and described by the Brazilian physician Carlos Chagas in 1909. After a century of original description, trypanosomiasis still brings much misery to humanity and is classified as a neglected tropical disease prevalent in underdeveloped countries, particularly in South America. It is an increasing worldwide problem due to the number of cases in endemic areas and the migration of infected subjects to more developed regions, mainly North America and Europe. Despite its importance, chronic chagas cardiomyopathy (CCC pathophysiology is yet poorly understood, and independently of its social, clinical, and epidemiological importance, the therapeutic approach of CCC is still transposed from the knowledge acquired from other cardiomyopathies. Therefore, the objective of this review is to describe the treatment of Chagas cardiomyopathy with emphasis on its peculiarities.

  5. Viterbi training in PRISM

    OpenAIRE

    Sato, Taisuke; Kubota, Keiichi

    2013-01-01

    VT (Viterbi training), or hard EM, is an efficient way of parameter learning for probabilistic models with hidden variables. Given an observation $y$, it searches for a state of hidden variables $x$ that maximizes $p(x,y \\mid \\theta)$ by coordinate ascent on parameters $\\theta$ and $x$. In this paper we introduce VT to PRISM, a logic-based probabilistic modeling system for generative models. VT improves PRISM in three ways. First VT in PRISM converges faster than EM in PRISM due to the VT's t...

  6. The PRISM Benchmark Suite

    OpenAIRE

    Kwiatkowsa, Marta; Norman, Gethin; Parker, David

    2012-01-01

    We present the PRISM benchmark suite: a collection of probabilistic models and property specifications, designed to facilitate testing, benchmarking and comparisons of probabilistic verification tools and implementations.

  7. Chagas disease in prehistory

    Directory of Open Access Journals (Sweden)

    Luiz F. Ferreira

    2011-09-01

    Full Text Available The classical hypothesis proposes that Chagas disease has been originated in the Andean region among prehistoric people when they started domesticating animals, changing to sedentary habits, and adopting agriculture. These changes in their way of life happened nearly 6,000 years ago. However, paleoparasitological data based on molecular tools showed that Trypanosoma cruzi infection and Chagas disease were commonly found both in South and North American prehistoric populations long before that time, suggesting that Chagas disease may be as old as the human presence in the American continent. The study of the origin and dispersion of Trypanosoma cruzi infection among prehistoric human populations may help in the comprehension of the clinical and epidemiological questions on Chagas disease that still remain unanswered.A hipótese clássica sobre a origem da doença de Chagas propõe que tenha surgido entre as populações pré-históricas dos Andes quando começaram a domesticar animais, mudaram para hábitos sedentários e adotaram a agricultura. Estas mudanças em seus hábitos de vida aconteceram há aproximadamente 6.000 anos. Entretanto, os dados da paleoparasitologia, baseados na biologia molecular, mostraram que a infecção por Trypanosoma cruzi e a doença de Chagas eram comuns tanto em populações pré-históricas da América do Sul e América do Norte muito antes deste período. De acordo com os dados paleoparasitológicos, a doença de Chagas pode ser tão antiga quanto a presença humana no continente americano. O estudo sobre a origem e dispersão da infecção por Trypanosoma cruzi entre populações humanas pré-históricas pode auxiliar na compreensão de questões clínicas e epidemiológicas sobre a doença de Chagas que ainda permanecem sem resposta.

  8. PRISM Spectrograph Optical Design

    Science.gov (United States)

    Chipman, Russell A.

    1995-01-01

    The objective of this contract is to explore optical design concepts for the PRISM spectrograph and produce a preliminary optical design. An exciting optical configuration has been developed which will allow both wavelength bands to be imaged onto the same detector array. At present the optical design is only partially complete because PRISM will require a fairly elaborate optical system to meet its specification for throughput (area*solid angle). The most complex part of the design, the spectrograph camera, is complete, providing proof of principle that a feasible design is attainable. This camera requires 3 aspheric mirrors to fit inside the 20x60 cm cross-section package. A complete design with reduced throughput (1/9th) has been prepared. The design documents the optical configuration concept. A suitable dispersing prism material, CdTe, has been identified for the prism spectrograph, after a comparison of many materials.

  9. Acoustic dispersive prism

    OpenAIRE

    Hussein Esfahlani; Sami Karkar; Herve Lissek; Mosig, Juan R.

    2016-01-01

    The optical dispersive prism is a well-studied element, which allows separating white light into its constituent spectral colors, and stands in nature as water droplets. In analogy to this definition, the acoustic dispersive prism should be an acoustic device with capability of splitting a broadband acoustic wave into its constituent Fourier components. However, due to the acoustical nature of materials as well as the design and fabrication difficulties, there is neither any natural acoustic ...

  10. Chagas Disease, France

    OpenAIRE

    Lescure, François-Xavier; Canestri, Ana; Melliez, Hugues; Jauréguiberry, Stéphane; Develoux, Michel; Dorent, Richard; Guiard-Schmid, Jean-Baptiste; Bonnard, Philippe; Ajana, Faïza; Rolla, Valeria; Carlier, Yves; Gay, Frederick; Elghouzzi, Marie-Hélène; Danis, Martin; Pialoux, Gilles

    2008-01-01

    Chagas disease (CD) is endemic to Latin America; its prevalence is highest in Bolivia. CD is sometimes seen in the United States and Canada among migrants from Latin America, whereas it is rare in Europe. We report 9 cases of imported CD in France from 2004 to 2006.

  11. Geometric formula for prism deflection

    Indian Academy of Sciences (India)

    Apoorva G Wagh; Veer Chand Rakhecha

    2004-08-01

    While studying neutron deflections produced by a magnetic prism, we have stumbled upon a simple `geometric' formula. For a prism of refractive index close to unity, the deflection simply equals the product of the refractive power − 1 and the base-to-height ratio of the prism, regardless of the apex angle. The base and height of the prism are measured respectively along and perpendicular to the direction of beam propagation within the prism. The geometric formula greatly simplifies the optimisation of prism parameters to suit any specific experiment.

  12. PRISM project optical instrument

    Science.gov (United States)

    Taylor, Charles R.

    1994-01-01

    The scientific goal of the Passively-cooled Reconnaissance of the InterStellar Medium (PRISM) project is to map the emission of molecular hydrogen at 17.035 micrometers and 28.221 micrometers. Since the atmosphere is opaque at these infrared wavelengths, an orbiting telescope is being studied. The availability of infrared focal plane arrays enables infrared imaging spectroscopy at the molecular hydrogen wavelengths. The array proposed for PRISM is 128 pixels square, with a pixel size of 75 micrometers. In order to map the sky in a period of six months, and to resolve the nearer molecular clouds, each pixel must cover 0.5 arcminutes. This sets the focal length at 51.6 cm. In order for the pixel size to be half the diameter of the central diffraction peak at 28 micrometers would require a telescope aperture of 24 cm; an aperture of 60 cm has been selected for the PRISM study for greater light gathering power.

  13. Chagas' disease and AIDS

    OpenAIRE

    Vaidian, Anil K; Louis M Weiss; Tanowitz, Herbert B.

    2004-01-01

    Chagas' disease caused by Trypanosoma cruzi is an opportunistic infection in the setting of HIV/AIDS. Some individuals with HIV and chronic T. cruzi infection may experience a reactivation, which is most commonly manifested by meningoencephalitis. A reactivation myocarditis is the second most common manifestation. These presentations may be difficult to distinguish from toxoplasmosis in individuals with HIV/AIDS. The overlap of HIV and Trypanosoma cruzi infection occurs not only in endemic ar...

  14. Prism vergence measurements following adaptation to a base out prism

    OpenAIRE

    Tuff, L.C.; Firth, A Y; Griffiths, H.J.

    2000-01-01

    This study examines the effect of adaptation on the prism vergence range following an induced deviation. Five young adult subjects, with normal binocular functions, underwent fusional verfence testing to base in prisms before and after wearing a 10(Δ) base out Fresnel prism. The Fresnel prism was worn for a period of 2, 5, or 10 min on each of three separate occasions. The base in fusional vergence showed no statistical difference before or after adaptation, for any of the time periods. Also ...

  15. Ultra-dispersive adaptive prism

    OpenAIRE

    Sautenkov, Vladimir A.; Li, Hebin; Rostovtsev, Yuri V.; Scully, Marlan O.

    2007-01-01

    We have experimentally demonstrated an ultra-dispersive optical prism made from coherently driven Rb atomic vapor. The prism possesses spectral angular dispersion that is six orders of magnitude higher than that of a prism made of optical glass; it is the highest spectral angular dispersion that has ever been shown (such angular dispersion allows one to spatially resolve light beams with different frequencies separated by a few kHz). The prism operates near the resonant frequency of atomic va...

  16. Prism Adaptation in Schizophrenia

    Science.gov (United States)

    Bigelow, Nirav O.; Turner, Beth M.; Andreasen, Nancy C.; Paulsen, Jane S.; O'Leary, Daniel S.; Ho, Beng-Choon

    2006-01-01

    The prism adaptation test examines procedural learning (PL) in which performance facilitation occurs with practice on tasks without the need for conscious awareness. Dynamic interactions between frontostriatal cortices, basal ganglia, and the cerebellum have been shown to play key roles in PL. Disruptions within these neural networks have also…

  17. Generalization of Prism Adaptation

    Science.gov (United States)

    Redding, Gordon M.; Wallace, Benjamin

    2006-01-01

    Prism exposure produces 2 kinds of adaptive response. Recalibration is ordinary strategic remapping of spatially coded movement commands to rapidly reduce performance error. Realignment is the extraordinary process of transforming spatial maps to bring the origins of coordinate systems into correspondence. Realignment occurs when spatial…

  18. Reflection by Porro Prisms

    Science.gov (United States)

    Greenslade, Thomas B.

    2010-04-01

    Students all know that reflection from a plane mirror produces an image that is reversed right to left and so cannot be read by anyone but Leonardo da Vinci, who kept his notes in mirror writing. A useful counter-example is the Porro prism, which produces an image that is not reversed.

  19. A displacement-doubling prism

    International Nuclear Information System (INIS)

    A novel prism has been devised which can be used in place of the ‘flag’ in an optical shadow-sensing type of displacement sensor, for example. In this way, theoretically the displacement sensitivity of the sensor can be doubled. Such a prism has been manufactured, and its displacement-doubling property has been verified. - Highlights: • A new type of glass prism doubles linear displacement of optical beams. • Optical operation has been verified. • Light beams enter and exit at normal incidence to prism's windows. • Optical path length through prism remains constant, as prism is moved. • Designed to double the displacement sensitivity of knife-edge shadow sensors

  20. Control of Chagas disease vectors

    OpenAIRE

    JM Ramsey; CJ Schofield

    2003-01-01

    Most Latin American countries are making dramatic progress in controlling Chagas disease, through a series of national and international initiatives focusing on elimination of domestic populations of Triatominae, improved screening of blood donors, and clinical support and treatment of persons infected with Trypanosoma cruzi. Some countries, particularly Uruguay, Chile and Brazil, are sufficiently advanced in their programmes to initiate detailed planning of the subsequent phases of Chagas di...

  1. Ventricular arrhythmias in Chagas disease

    Directory of Open Access Journals (Sweden)

    Marco Paulo Tomaz Barbosa

    2015-02-01

    Full Text Available Sudden death is one of the most characteristic phenomena of Chagas disease, and approximately one-third of infected patients develop life-threatening heart disease, including malignant ventricular arrhythmias. Fibrotic lesions secondary to chronic cardiomyopathy produce arrhythmogenic substrates that lead to the appearance and maintenance of ventricular arrhythmias. The objective of this study is to discuss the main clinical and epidemiological aspects of ventricular arrhythmias in Chagas disease, the specific workups and treatments for these abnormalities, and the breakthroughs needed to determine a more effective approach to these arrhythmias. A literature review was performed via a search of the PubMed database from 1965 to May 31, 2014 for studies of patients with Chagas disease. Clinical management of patients with chronic Chagas disease begins with proper clinical stratification and the identification of individuals at a higher risk of sudden cardiac death. Once a patient develops malignant ventricular arrhythmia, the therapeutic approach aims to prevent the recurrence of arrhythmias and sudden cardiac death by the use of implantable cardioverter defibrillators, antiarrhythmic drugs, or both. In select cases, invasive ablation of the reentrant circuit causing tachycardia may be useful. Ventricular arrhythmias are important manifestations of Chagas cardiomyopathy. This review highlights the absence of high-quality evidence regarding the treatment of ventricular arrhythmias in Chagas disease. Recognizing high-risk patients who require specific therapies, especially invasive procedures such as the implantation of cardioverter defibrillators and ablative approaches, is a major challenge in clinical practice.

  2. Multibeam collimator uses prism stack

    Science.gov (United States)

    Minott, P. O.

    1981-01-01

    Optical instrument creates many divergent light beams for surveying and machine element alignment applications. Angles and refractive indices of stack of prisms are selected to divert incoming laser beam by small increments, different for each prism. Angles of emerging beams thus differ by small, precisely-controlled amounts. Instrument is nearly immune to vibration, changes in gravitational force, temperature variations, and mechanical distortion.

  3. Control of Chagas disease vectors

    Directory of Open Access Journals (Sweden)

    Ramsey JM

    2003-01-01

    Full Text Available Most Latin American countries are making dramatic progress in controlling Chagas disease, through a series of national and international initiatives focusing on elimination of domestic populations of Triatominae, improved screening of blood donors, and clinical support and treatment of persons infected with Trypanosoma cruzi. Some countries, particularly Uruguay, Chile and Brazil, are sufficiently advanced in their programmes to initiate detailed planning of the subsequent phases of Chagas disease control, while others such as Peru, Ecuador, and Mexico, are currently applying only the initial phases of the control campaigns. In this review, we seek to provide a brief history of the campaigns as a basis for discussion of future interventions. Our aim is to relate operational needs to the underlying biological aspects that have made Chagas disease so serious in Latin America but have also revealed the epidemiological vulnerability of this disease.

  4. 21 CFR 886.1660 - Gonioscopic prism.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gonioscopic prism. 886.1660 Section 886.1660 Food... DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1660 Gonioscopic prism. (a) Identification. A gonioscopic prism is a device that is a prism intended to be placed on the eye to study the anterior...

  5. Prism Window for Optical Alignment

    Science.gov (United States)

    Tang, Hong

    2008-01-01

    A prism window has been devised for use, with an autocollimator, in aligning optical components that are (1) required to be oriented parallel to each other and/or at a specified angle of incidence with respect to a common optical path and (2) mounted at different positions along the common optical path. The prism window can also be used to align a single optical component at a specified angle of incidence. Prism windows could be generally useful for orienting optical components in manufacture of optical instruments. "Prism window" denotes an application-specific unit comprising two beam-splitter windows that are bonded together at an angle chosen to obtain the specified angle of incidence.

  6. Chagas Disease: No Longer Exotic

    Centers for Disease Control (CDC) Podcasts

    2008-04-03

    This podcast is designed to inform health care providers about Chagas disease, diagnosis, and treatment and to assist in identifying infected patients.  Created: 4/3/2008 by National Center for Zoonotic, Vector-Borne, and Enteric Diseases (NCZVED).   Date Released: 4/8/2008.

  7. A neutron prism

    International Nuclear Information System (INIS)

    A neutron detector with an energy and time resolution makes it possible to realize a new type of a scattering instrument. Such kind of detector can be developed by combining the neutron refractive device (neutron prism) and position-sensitive-detector (PSD) with a time resolution. As the neutron refractive device, two candidates are considered; a compound refractive device and magnetic field gradient. In former case, suitable choice of material and design of the refractive device overcomes a problem of neutron absorption and weak refraction due to material. On the other hand, the magnetic field gradient has an advantage that it has a large refraction and zero neutron absorption comparing with the compound refractive device. A refractive device has been developed with suitable material and design for neutron optics and a quadrupole magnet with permanent magnets in which a constant field gradient is realized. In this paper, the construction and performance of the energy and time resoluble detectors using the neutron refractive devices are described and their application to a neutron scattering experiment is discussed. (author)

  8. Experimental Chagas' disease in dogs

    Directory of Open Access Journals (Sweden)

    Marta de Lana

    1992-03-01

    Full Text Available This paper describes the development of experimental Chagas' disease in 64 out-bred young dogs. Twenty-nine animals were inoculated with the Be-62 and 35 with Be-78 Trypanosoma cruzi strains. Twenty-six were infected with blood trypomastigotes by different inoculation routes and 38 with metacyclic trypomastigotes from the vector via the conjunctival route. Twenty of the 26 dogs infected with blood trypomastigotes were autopsied during the acute phase. Eleven died spontaneously and nine were sacrificed. Six remained alive until they died suddenly (two or were autopsied (four. Twelve of the 38 dogs infected with metacyclic trypomastigotes evolved naturally to the chronic phase and remained alive for 24-48 months. The parasitemia, clinical aspects and serology (IgM and IgG as well as electrocardiogram, hemogram and heart anatomo-histopathologic patterns of acute and chronic cardiac forms of Chagas' disease as seen in human infections, were reproduced. The most important finding is the reproductibility of diffuse fibrosing chronic chagasic cardiopathy in all dogs infected with Be-78 T. cruzi strain autopsied between the 90th and 864th days of infection. Thus, the dog can be considered as a suitable experimental model to study Chagas' disease according to the requisites of the World Health Organization (1984. Futhermore the animal is easily obtained and easy to handle and maintain in experimental laboratory conditions.

  9. Rotatable prism for pan and tilt

    Science.gov (United States)

    Ball, W. B.

    1980-01-01

    Compact, inexpensive, motor-driven prisms change field of view of TV camera. Camera and prism rotate about lens axis to produce pan effect. Rotating prism around axis parallel to lens produces tilt. Size of drive unit and required clearance are little more than size of camera.

  10. Preserving with Prisms: Producing Nets

    Science.gov (United States)

    Prummer, Kathy E.; Amador, Julie M.; Wallin, Abraham J.

    2016-01-01

    Two mathematics teachers in a small rural school decided to create a task that would engage seventh graders. The goal of the real-world activity was to help students develop geometric and spatial reasoning and to support their understanding of volume of rectangular prisms. The impetus for the task came from the teachers' desire to engage students…

  11. The chronic gastrointestinal manifestations of Chagas disease

    Directory of Open Access Journals (Sweden)

    Nilce Mitiko Matsuda

    2009-01-01

    Full Text Available Chagas disease is an infectious disease caused by the protozoan Trypanosoma cruzi. The disease mainly affects the nervous system, digestive system and heart. The objective of this review is to revise the literature and summarize the main chronic gastrointestinal manifestations of Chagas disease. The chronic gastrointestinal manifestations of Chagas disease are mainly a result of enteric nervous system impairment caused by T. cruzi infection. The anatomical locations most commonly described to be affected by Chagas disease are salivary glands, esophagus, lower esophageal sphincter, stomach, small intestine, colon, gallbladder and biliary tree. Chagas disease has also been studied in association with Helicobacter pylori infection, interstitial cells of Cajal and the incidence of gastrointestinal cancer.

  12. A Liquid Prism for Refractive Index Studies

    Science.gov (United States)

    Edmiston, Michael D.

    2001-11-01

    A hollow glass prism filled with liquid becomes a "liquid prism". A simple method for constructing hollow glass prisms is presented. A method is given for a demonstration that uses the liquid prism with a laser or laser pointer so the audience can observe differences in refractive index for various liquids. The demonstration provides a quick and easy determination of the sugar content of soft drinks and juices. The prism makes it easy to determine a numerical value for the refractive index of a liquid.

  13. Dispersion Compensation using a Prism-pair

    OpenAIRE

    Shaked, Yaakov; Yefet, Shai; Pe'er, Avi

    2014-01-01

    A simple and intuitive formulation is reviewed for the Brewster prism-pair - A most common component in spectroscopy-oriented experiments using ultrashort pulses. This review aims to provide students and beginners in the field of spectroscopy with a unified description of a major experimental component. The total spectral phase experienced by a broadband light field is calculated after passing through a pair of Brewster-cut prisms, demonstrating the flexibility of the prism pair to provide tu...

  14. Neutron forward diffraction by single crystal prisms

    Indian Academy of Sciences (India)

    Sohrab Abbas; Apoorva G Wagh; Markus Strobl; Wolfgang Treimer

    2008-11-01

    We have derived analytic expressions for the deflection as well as transmitted fraction of monochromatic neutrons forward diffracted by a single crystal prism. In the vicinity of a Bragg reflection, the neutron deflection deviates sharply from that for an amorphous prism, exhibiting three orders of magnitude greater sensitivity to the incidence angle. We have measured the variation of neutron deflection and transmission across a Bragg reflection, for several single crystal prisms. The results agree well with theory.

  15. Preoperative prism adaptation test in normosensoric strabismus

    OpenAIRE

    Schildwächter-von Langenthal, Annette; Kommerell, Guntram; Klein, Ulrike; Simonsz, Huib

    1989-01-01

    textabstractIn 19 patients with normosensoric esotropia, the squint angles measured with the alternate cover test were compared with those after prolonged prismatic correction of the squint angle and with those after prolonged occlusion of one eye. All patients showed an increase of the squint angle after prism adaptation. The angle was generally smaller after diagnostic occlusion of one eye than after prism adaptation. We assume that the increase in the squint angle after prism adaptation is...

  16. Chagas Disease Cardiomyopathy: Immunopathology and Genetics

    Directory of Open Access Journals (Sweden)

    Edecio Cunha-Neto

    2014-01-01

    Full Text Available Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Latin America and affects ca. 10 million people worldwide. About 30% of Chagas disease patients develop chronic Chagas disease cardiomyopathy (CCC, a particularly lethal inflammatory cardiomyopathy that occurs decades after the initial infection, while most patients remain asymptomatic. Mortality rate is higher than that of noninflammatory cardiomyopathy. CCC heart lesions present a Th1 T-cell-rich myocarditis, with cardiomyocyte hypertrophy and prominent fibrosis. Data suggest that the myocarditis plays a major pathogenetic role in disease progression. Major unmet goals include the thorough understanding of disease pathogenesis and therapeutic targets and identification of prognostic genetic factors. Chagas disease thus remains a neglected disease, with no vaccines or antiparasitic drugs proven efficient in chronically infected adults, when most patients are diagnosed. Both familial aggregation of CCC cases and the fact that only 30% of infected patients develop CCC suggest there might be a genetic component to disease susceptibility. Moreover, previous case-control studies have identified some genes associated to human susceptibility to CCC. In this paper, we will review the immunopathogenesis and genetics of Chagas disease, highlighting studies that shed light on the differential progression of Chagas disease patients to CCC.

  17. Cell Therapy in Chagas Disease

    Directory of Open Access Journals (Sweden)

    Antonio C. Campos de Carvalho

    2009-01-01

    Full Text Available Chagas disease which is caused by the parasite Trypanosoma cruzi is an important cause of cardiomyopathy in Latin America. In later stages chagasic cardiomyopathy is associated with congestive heart failure which is often refractory to medical therapy. In these individuals heart transplantation has been attempted. However, this procedure is fraught with many problems attributable to the surgery and the postsurgical administration of immunosuppressive drugs. Studies in mice suggest that the transplantation of bone-marrow-derived cells ameliorates the inflammation and fibrosis in the heart associated with this infection. Cardiac magnetic resonance imaging reveals that bone marrow transplantation ameliorates the infection induced right ventricular enlargement. On the basis of these animal studies the safety of autologous bone marrow transplantation has been assessed in patients with chagasic end-stage heart disease. The initial results are encouraging and more studies need to be performed.

  18. Carlos Chagas Discoveries as a Drop Back to Scientific Construction of Chronic Chagas Heart Disease

    Directory of Open Access Journals (Sweden)

    Reinaldo B. Bestetti

    2016-01-01

    Full Text Available Abstract The scientific construction of chronic Chagas heart disease (CCHD started in 1910 when Carlos Chagas highlighted the presence of cardiac arrhythmia during physical examination of patients with chronic Chagas disease, and described a case of heart failure associated with myocardial inflammation and nests of parasites at autopsy. He described sudden cardiac death associated with arrhythmias in 1911, and its association with complete AV block detected by Jacquet's polygraph as Chagas reported in 1912. Chagas showed the presence of myocardial fibrosis underlying the clinical picture of CCHD in 1916, he presented a full characterization of the clinical aspects of CCHD in 1922. In 1928, Chagas detected fibrosis of the conductive system, and pointed out the presence of marked cardiomegaly at the chest X-Ray associated with minimal symptomatology. The use of serological reaction to diagnose CCHD was put into clinical practice in 1936, after Chagas' death, which along with the 12-lead ECG, revealed the epidemiological importance of CCHD in 1945. In 1953, the long period between initial infection and appearance of CCHD was established, whereas the annual incidence of CCHD from patients with the indeterminate form of the disease was established in 1956. The use of heart catheterization in 1965, exercise stress testing in 1973, Holter monitoring in 1975, Electrophysiologic testing in 1973, echocardiography in 1975, endomyocardial biopsy in 1981, and Magnetic Resonance Imaging in 1995, added to the fundamental clinical aspects of CCHD as described by Carlos Chagas.

  19. Carlos Chagas Discoveries as a Drop Back to Scientific Construction of Chronic Chagas Heart Disease

    Science.gov (United States)

    Bestetti, Reinaldo B.; Restini, Carolina Baraldi A.; Couto, Lucélio B.

    2016-01-01

    The scientific construction of chronic Chagas heart disease (CCHD) started in 1910 when Carlos Chagas highlighted the presence of cardiac arrhythmia during physical examination of patients with chronic Chagas disease, and described a case of heart failure associated with myocardial inflammation and nests of parasites at autopsy. He described sudden cardiac death associated with arrhythmias in 1911, and its association with complete AV block detected by Jacquet's polygraph as Chagas reported in 1912. Chagas showed the presence of myocardial fibrosis underlying the clinical picture of CCHD in 1916, he presented a full characterization of the clinical aspects of CCHD in 1922. In 1928, Chagas detected fibrosis of the conductive system, and pointed out the presence of marked cardiomegaly at the chest X-Ray associated with minimal symptomatology. The use of serological reaction to diagnose CCHD was put into clinical practice in 1936, after Chagas' death, which along with the 12-lead ECG, revealed the epidemiological importance of CCHD in 1945. In 1953, the long period between initial infection and appearance of CCHD was established, whereas the annual incidence of CCHD from patients with the indeterminate form of the disease was established in 1956. The use of heart catheterization in 1965, exercise stress testing in 1973, Holter monitoring in 1975, Electrophysiologic testing in 1973, echocardiography in 1975, endomyocardial biopsy in 1981, and Magnetic Resonance Imaging in 1995, added to the fundamental clinical aspects of CCHD as described by Carlos Chagas. PMID:27223644

  20. Carlos Chagas Discoveries as a Drop Back to Scientific Construction of Chronic Chagas Heart Disease.

    Science.gov (United States)

    Bestetti, Reinaldo B; Restini, Carolina Baraldi A; Couto, Lucélio B

    2016-07-01

    The scientific construction of chronic Chagas heart disease (CCHD) started in 1910 when Carlos Chagas highlighted the presence of cardiac arrhythmia during physical examination of patients with chronic Chagas disease, and described a case of heart failure associated with myocardial inflammation and nests of parasites at autopsy. He described sudden cardiac death associated with arrhythmias in 1911, and its association with complete AV block detected by Jacquet's polygraph as Chagas reported in 1912. Chagas showed the presence of myocardial fibrosis underlying the clinical picture of CCHD in 1916, he presented a full characterization of the clinical aspects of CCHD in 1922. In 1928, Chagas detected fibrosis of the conductive system, and pointed out the presence of marked cardiomegaly at the chest X-Ray associated with minimal symptomatology. The use of serological reaction to diagnose CCHD was put into clinical practice in 1936, after Chagas' death, which along with the 12-lead ECG, revealed the epidemiological importance of CCHD in 1945. In 1953, the long period between initial infection and appearance of CCHD was established, whereas the annual incidence of CCHD from patients with the indeterminate form of the disease was established in 1956. The use of heart catheterization in 1965, exercise stress testing in 1973, Holter monitoring in 1975, Electrophysiologic testing in 1973, echocardiography in 1975, endomyocardial biopsy in 1981, and Magnetic Resonance Imaging in 1995, added to the fundamental clinical aspects of CCHD as described by Carlos Chagas. PMID:27223644

  1. The PRISM/PRIME Project

    International Nuclear Information System (INIS)

    Lepton Flavour violation is predicted by many theories beyond the standard model. In the muon sector such a violation entails not only direct μ→eγ decay but also the conversion process μ→e. To measure this to high precision requires a large number of muons of very similar energy, and this is difficult to achieve from a muon target with conventional beam optics. PRISM is an FFAG system designed to accept large numbers of muons (1012/sec) with a wide range of energies, and render them monochromatic by accelerating the less energetic muons and decelerating the more energetic ones. To preserve Liouville's theorem, this is accompanied by a broadening in the timing of the muons, hence the name 'Phase Rotated Intense Slow Muon source.' The principles of this device have been demonstrated and components prototyped. PRIME is a detector (PRISM Muon Electron Conversion) which has been designed to stop 20 MeV bunches of muons in a thin foil, giving a very clean signal and reaching a background sensitivity of 10-18, four orders of magnitude better than today's limits and probing the interesting region for BSM theories.

  2. Immunosuppression and Chagas disease: a management challenge.

    Directory of Open Access Journals (Sweden)

    María-Jesús Pinazo

    Full Text Available Immunosuppression, which has become an increasingly relevant clinical condition in the last 50 years, modifies the natural history of Trypanosoma cruzi infection in most patients with Chagas disease. The main goal in this setting is to prevent the consequences of reactivation of T. cruzi infection by close monitoring. We analyze the relationship between Chagas disease and three immunosuppressant conditions, including a description of clinical cases seen at our center, a brief review of the literature, and recommendations for the management of these patients based on our experience and on the data in the literature. T. cruzi infection is considered an opportunistic parasitic infection indicative of AIDS, and clinical manifestations of reactivation are more severe than in acute Chagas disease. Parasitemia is the most important defining feature of reactivation. Treatment with benznidazole and/or nifurtimox is strongly recommended in such cases. It seems reasonable to administer trypanocidal treatment only to asymptomatic immunosuppressed patients with detectable parasitemia, and/or patients with clinically defined reactivation. Specific treatment for Chagas disease does not appear to be related to a higher incidence of neoplasms, and a direct role of T. cruzi in the etiology of neoplastic disease has not been confirmed. Systemic immunosuppressive diseases or immunosuppressants can modify the natural course of T. cruzi infection. Immunosuppressive doses of corticosteroids have not been associated with higher rates of reactivation of Chagas disease. Despite a lack of evidence-based data, treatment with benznidazole or nifurtimox should be initiated before immunosuppression where possible to reduce the risk of reactivation. Timely antiparasitic treatment with benznidazole and nifurtimox (or with posaconazole in cases of therapeutic failure has proven to be highly effective in preventing Chagas disease reactivation, even if such treatment has not been

  3. Waveguide Prism Based on Porous Silicon

    Institute of Scientific and Technical Information of China (English)

    JIA Zhen-hong

    2004-01-01

    The fabrication of the oxidized porous silicon waveguide prism is reported by selectively electrochemical anodisation process. The direction changes of light beams in TE and TM polarization out of this waveguide prism were respectively measured,and the experimental results were analyzed.

  4. PRISM: FFAG as a phase rotator

    International Nuclear Information System (INIS)

    PRISM is a project in Japan to make a high-intensity low-energy muon source with a narrow energy-spread and high purity. In this report, we present an overview of the PRISM project and its physics applications, especially to a search for muon lepton flavor violation. Its future extension towards a neutrino factory is also mentioned. (author)

  5. The Prism Plastic Calorimeter (PPC)

    CERN Multimedia

    2002-01-01

    This proposal supports two goals: \\\\ \\\\ First goal:~~Demonstrate that current, widely used plastic technologies allow to design Prism Plastic Calorimeter~(PPC) towers with a new ``liquid crystal'' type plastic called Vectra. It will be shown that this technique meets the requirements for a LHC calorimeter with warm liquids: safety, hermeticity, hadronic compensation, resolution and time response. \\\\ \\\\ Second goal:~~Describe how one can design a warm liquid calorimeter integrated into a LHC detector and to list the advantages of the PPC: low price, minimum of mechanical structures, minimum of dead space, easiness of mechanical assembly, accessibility to the electronics, possibility to recirculate the liquid. The absorber and the electronic being outside of the liquid and easily accessible, one has maximum flexibility to define them. \\\\ \\\\ The R&D program, we define here aims at showing the feasibility of these new ideas by building nine towers of twenty gaps and exposing them to electron and hadron beams.

  6. Demagnetizing effects in stacked rectangular prisms

    DEFF Research Database (Denmark)

    Christensen, Dennis; Nielsen, Kaspar Kirstein; Bahl, Christian Robert Haffenden;

    2011-01-01

    configuration, temperature distribution and applied magnetic field. In this paper the model is applied to the case of a stack of parallel, ferromagnetic rectangular prisms and the resulting internal field is found as a function of the orientation of the applied field, the number of prisms in the stack, the...... spacing between the prisms and the packing density of the stack. The results show that the resulting internal field is far from being equal to the applied field and that the various stack configurations investigated affect the resulting internal field significantly and non-linearly. The results have a...

  7. Highly dispersive photonic band-gap prism

    International Nuclear Information System (INIS)

    We propose the concept of a photonic band-gap (PBG) prism based on two-dimensional PBG structures and realize it in the millimeter-wave spectral regime. We recognize the highly nonlinear dispersion of PBG materials near Brillouin zone edges and utilize the dispersion to achieve strong prism action. Such a PBG prism is very compact if operated in the optical regime, ∼20μm in size for λ∼700nm, and can serve as a dispersive element for building ultracompact miniature spectrometers. copyright 1996 Optical Society of America

  8. Highly dispersive photonic band-gap prism.

    Science.gov (United States)

    Lin, S Y; Hietala, V M; Wang, L; Jones, E D

    1996-11-01

    We propose the concept of a photonic band-gap (PBG) prism based on two-dimensional PBG structures and realize it in the millimeter-wave spectral regime. We recognize the highly nonlinear dispersion of PBG materials near Brillouin zone edges and utilize the dispersion to achieve strong prism action. Such a PBG prism is very compact if operated in the optical regime, ~20 mm in size for lambda ~ 700 nm, and can serve as a dispersive element for building ultracompact miniature spectrometers. PMID:19881796

  9. CHR(PRISM)-based probabilistic logic learning

    OpenAIRE

    Sneyers, Jon; Meert, Wannes; Vennekens, Joost; Kameya, Yoshitaka; Sato, Taisuke

    2010-01-01

    PRISM is an extension of Prolog with probabilistic predicates and built-in support for expectation-maximization learning. Constraint Handling Rules (CHR) is a high-level programming language based on multi-headed multiset rewrite rules. In this paper, we introduce a new probabilistic logic formalism, called CHRiSM, based on a combination of CHR and PRISM. It can be used for high-level rapid prototyping of complex statistical models by means of "chance rules". The underlying PRISM system can t...

  10. A prism carbon molecule C$_20$

    OpenAIRE

    OHNO, Koichi; Satoh, Hiroko; Iwamoto, Takeaki

    2015-01-01

    A new carbon family with a prism structure has been found by quantum chemical calculations. The prism-$C_20$ has a $D_10h$ structure with double-layered decagonal rings connected each other by ten vertical CC bonds. The CC bond lengths are 0.144 nm on the decagonal rings and 0.148 nm on the side faces. The diameter of the ring is 0.465 nm. The $prism-C_20$ is expected to be stable, since the lowest energy barrier from it was estimated to be 158.0 kJ mol$^−1$.

  11. 21 CFR 886.1650 - Ophthalmic bar prism.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ophthalmic bar prism. 886.1650 Section 886.1650...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1650 Ophthalmic bar prism. (a) Identification. An ophthalmic bar prism is a device that is a bar composed of fused prisms of gradually...

  12. Portable Remote Imaging Spectrometer (PRISM) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop an UV-NIR (350nm to 1050 nm) portable remote imaging spectrometer (PRISM) for flight on a variety of airborne platforms with high SNR and response...

  13. Random prism: an alternative to random forests

    OpenAIRE

    Stahl, F.; Bramer, Max

    2012-01-01

    Ensemble learning techniques generate multiple classifiers, so called base classifiers, whose combined classification results are used in order to increase the overall classification accuracy. In most ensemble classifiers the base classifiers are based on the Top Down Induction of Decision Trees (TDIDT) approach. However, an alternative approach for the induction of rule based classifiers is the Prism family of algorithms. Prism algorithms produce modular classification rules that do not nece...

  14. Pillars and pinning centers in superconducting prisms

    International Nuclear Information System (INIS)

    We solve the Ginzburg-Landau equations for to study the vortex configurations in a superconducting prism with a square array of pillars or holes in the presence of a uniform applied magnetic field. The presence of the pillars (holes) changes the vortex structures in the superconducting prism considerably. We calculate magnetization, free energy and vorticity curves, which shows the transition between different vortex configurations as a function of magnetic fields

  15. Recent studies on the PRISM FFAG ring

    International Nuclear Information System (INIS)

    Next generation lepton flavour violation experiments require high intensity and high quality muon beams. The PRISM Task Force focuses on accelerator R and D for realizing such beams using an FFAG ring. The scaling and non-scaling designs for the PRISM FFAG ring are discussed. The recent studies on injection/extraction systems and matching to the solenoid channel are outlined. The future plans for the study are presented.

  16. Neutron energy analysis by silicon prisms

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, J., E-mail: jennifer.schulz@helmholtz-berlin.de [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Ott, F. [Laboratoire Leon Brillouin, Bât 563 CEA Saclay, 91191 Gif sur Yvette Cedex (France); Hülsen, Ch.; Krist, Th. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany)

    2013-11-21

    Neutron energy analysing by refraction with prisms allows to measure different wavelengths at the same time thus avoiding losses due to monochromatization. We built and tested a refractive energy analysing device made from small prisms, where losses only occur due to the attenuation in the material. We measured the refraction and the transmission of MgF{sub 2} and Si prisms at the V14 reflectometer in Berlin at 4.9 Å to check their applicability. The experimentally determined linear attenuation coefficients are 0.055 cm{sup −1} for the MgF{sub 2} and 0.03 cm{sup −1} for the Si prisms. An energy analyser consisting of silicon prism layers was measured at the EROS reflectometer at the LLB in a white neutron beam. The useful wavelength band was 2.4–7.6 Å. At 6.7 Å a wavelength resolution of 5% and a transmission of 53% were achieved. The surface roughness of the prisms could be determined to be (0.011±0.006)deg.

  17. Demagnetizing effects in stacked rectangular prisms

    International Nuclear Information System (INIS)

    A numerical, magnetostatic model of the internal magnetic field of a rectangular prism is extended to the case of a stack of rectangular prisms. The model enables the calculation of the spatially resolved, three-dimensional internal field in such a stack given any magnetic state function, stack configuration, temperature distribution and applied magnetic field. In this paper the model is applied to the case of a stack of parallel, ferromagnetic rectangular prisms and the resulting internal field is found as a function of the orientation of the applied field, the number of prisms in the stack, the spacing between the prisms and the packing density of the stack. The results show that the resulting internal field is far from being equal to the applied field and that the various stack configurations investigated affect the resulting internal field significantly and non-linearly. The results have a direct impact on the design of, e.g., active magnetic regenerators made of stacked rectangular prisms in terms of optimizing the internal field.

  18. Neutron energy analysis by silicon prisms

    International Nuclear Information System (INIS)

    Neutron energy analysing by refraction with prisms allows to measure different wavelengths at the same time thus avoiding losses due to monochromatization. We built and tested a refractive energy analysing device made from small prisms, where losses only occur due to the attenuation in the material. We measured the refraction and the transmission of MgF2 and Si prisms at the V14 reflectometer in Berlin at 4.9 Å to check their applicability. The experimentally determined linear attenuation coefficients are 0.055 cm−1 for the MgF2 and 0.03 cm−1 for the Si prisms. An energy analyser consisting of silicon prism layers was measured at the EROS reflectometer at the LLB in a white neutron beam. The useful wavelength band was 2.4–7.6 Å. At 6.7 Å a wavelength resolution of 5% and a transmission of 53% were achieved. The surface roughness of the prisms could be determined to be (0.011±0.006)deg

  19. Chagas disease in the Amazon Region

    Directory of Open Access Journals (Sweden)

    Hugo Marcelo Aguilar

    2007-10-01

    Full Text Available The risk that Chagas disease becomes established as a major endemic threat in Amazonia (the world's largest tropical biome, today inhabited by over 30 million people relates to a complex set of interacting biological and social determinants. These include intense immigration from endemic areas (possibly introducing parasites and vectors, extensive landscape transformation with uncontrolled deforestation, and the great diversity of wild Trypanosoma cruzi reservoir hosts and vectors (25 species in nine genera, which maintain intense sylvatic transmission cycles. Invasion of houses by adventitious vectors (with infection rates > 60% is common, and focal adaptation of native triatomines to artificial structures has been reported. Both acute (~ 500 and chronic cases of autochthonous human Chagas disease have been documented beyond doubt in the region. Continuous, low-intensity transmission seems to occur throughout the Amazon, and generates a hypoendemic pattern with seropositivity rates of ~ 1-3%. Discrete foci also exist in which transmission is more intense (e.g., in localized outbreaks probably linked to oral transmission and prevalence rates higher. Early detection-treatment of acute cases is crucial for avoiding further dispersion of endemic transmission of Chagas disease in Amazonia, and will require the involvement of malaria control and primary health care systems. Comprehensive eco-epidemiological research, including prevalence surveys or the characterization of transmission dynamics in different ecological settings, is still needed. The International Initiative for Chagas Disesae Surveillance and Prevention in the Amazon provides the framework for building up the political and scientific cooperation networks required to confront the challenge of preventing Chagas disease in Amazonia.

  20. Serodiagnosis of chronic Chagas infection by using EIE-Recombinant-Chagas-Biomanguinhos kit

    Directory of Open Access Journals (Sweden)

    Gomes Yara M

    2001-01-01

    Full Text Available A kit based on an enzyme immunoassay, EIE-Recombinant-Chagas-Biomanguinhos, developed by the Oswaldo Cruz Foundation, was evaluated for the serodiagnosis of chronic Chagas disease. Evaluation was performed with 368 serum samples collected from individuals living in an endemic area for Chagas disease: 131 patients in the chronic phase with confirmed clinical, epidemiological, and serological diagnosis (indirect immunofluorescence, indirect hemagglutination or enzyme-linked immunosorbent assay and 237 nonchagasic seronegative individuals were considered negative control. The EIE-Recombinant-Chagas-Biomanguinhos kit showed high sensitivity, 100% (CI 95%: 96.4-100% and high specificity, 100% (CI 95%: 98-100%. The data obtained were in full agreement with clinical and conventional serology data. In addition, no cross-reaction was observed with sera from patients with cutaneous (n=14 and visceral (n=3 leishmaniasis. However, when these sera were tested by conventional serological assays for Chagas disease, cross-reactions were detected in 14.3% and 33.3% of the patients with cutaneous and visceral leishmaniasis, respectively. No cross-reactions were observed when sera from nonchagasic seronegative patients bearing other infectious disease (syphilis, n=8; HTLV, n=8; HCV, n=7 and HBV, n=12 were tested. In addition, sera of patients with inconclusive results for Chagas disease by conventional serology showed results in agreement with clinical evaluation, when tested by the kit. These results are relevant and indicate that the refered kit provides a safe immunodiagnosis of Chagas disease and could be used in blood bank screening.

  1. An improved prism energy analyzer for neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, J., E-mail: jennifer.schulz@helmholtz-berlin.de [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Ott, F. [Laboratoire Leon Brillouin, Bât 563 CEA Saclay, 91191 Gif sur Yvette Cedex (France); Krist, Th. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany)

    2014-04-21

    The effects of two improvements of an existing neutron energy analyzer consisting of stacked silicon prism rows are presented. First we tested the effect of coating the back of the prism rows with an absorbing layer to suppress neutron scattering by total reflection and by refraction at small angles. Experiments at HZB showed that this works perfectly. Second the prism rows were bent to shift the transmitted wavelength band to larger wavelengths. At HZB we showed that bending increased the transmission of neutrons with a wavelength of 4.9 Å. Experiments with a white beam at the EROS reflectometer at LLB showed that bending of the energy analyzing device to a radius of 7.9 m allows to shift the transmitted wavelength band from 0 to 9 Å to 2 to 16 Å.

  2. An improved prism energy analyzer for neutrons

    International Nuclear Information System (INIS)

    The effects of two improvements of an existing neutron energy analyzer consisting of stacked silicon prism rows are presented. First we tested the effect of coating the back of the prism rows with an absorbing layer to suppress neutron scattering by total reflection and by refraction at small angles. Experiments at HZB showed that this works perfectly. Second the prism rows were bent to shift the transmitted wavelength band to larger wavelengths. At HZB we showed that bending increased the transmission of neutrons with a wavelength of 4.9 Å. Experiments with a white beam at the EROS reflectometer at LLB showed that bending of the energy analyzing device to a radius of 7.9 m allows to shift the transmitted wavelength band from 0 to 9 Å to 2 to 16 Å

  3. Fresnel Prism on Hess Screen Test

    OpenAIRE

    Kyung Min Koh; Ungsoo Samuel Kim

    2013-01-01

    A 65-year-old male patient complained of diplopia after a cataract surgery. He had esotropia of 18 prism diopters (PDs) at distant and near deviation, and therefore, we performed the Hess screen test to identify any abnormal eye movement. However, the indicator was found to be out of bounds, and therefore, the test could not be completed. Therefore, the test was subsequently performed with a 20 PD base-out Fresnel prism, and an abduction deficit was observed in the right eye, but not in the l...

  4. Symmetry Breaking Analysis of Prism Adaptation's Latent Aftereffect

    Science.gov (United States)

    Frank, Till D.; Blau, Julia J. C.; Turvey, Michael T.

    2012-01-01

    The effect of prism adaptation on movement is typically reduced when the movement at test (prisms off) differs on some dimension from the movement at training (prisms on). Some adaptation is latent, however, and only revealed through further testing in which the movement at training is fully reinstated. Applying a nonlinear attractor dynamic model…

  5. 21 CFR 886.1655 - Ophthalmic Fresnel prism.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ophthalmic Fresnel prism. 886.1655 Section 886...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1655 Ophthalmic Fresnel prism. (a) Identification. An ophthalmic Fresnel prism is a device that is a thin plastic sheet with embossed rulings...

  6. 21 CFR 886.1665 - Ophthalmic rotary prism.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ophthalmic rotary prism. 886.1665 Section 886.1665...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1665 Ophthalmic rotary prism. (a) Identification. An ophthalmic rotary prism is a device with various prismatic powers intended to be handheld...

  7. 21 CFR 886.5810 - Ophthalmic prism reader.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ophthalmic prism reader. 886.5810 Section 886.5810...) MEDICAL DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5810 Ophthalmic prism reader. (a) Identification. An ophthalmic prism reader is a device intended for use by a patient who is in a supine...

  8. Comparing Volumes of Prisms and Pyramids

    Science.gov (United States)

    Vinogradova, Natalya

    2012-01-01

    Students' experience in using formulas for volumes is often limited to substituting numbers into given formulas. An activity presented in this article may help students make connections between the formulas for volumes of prisms and volumes of pyramids. In addition, some interesting facts from number theory arise, demonstrating strong connections…

  9. CHR(PRISM)-based Probabilistic Logic Learning

    CERN Document Server

    Sneyers, Jon; Vennekens, Joost; Kameya, Yoshitaka; Sato, Taisuke; 10.1017/S1471068410000207

    2010-01-01

    PRISM is an extension of Prolog with probabilistic predicates and built-in support for expectation-maximization learning. Constraint Handling Rules (CHR) is a high-level programming language based on multi-headed multiset rewrite rules. In this paper, we introduce a new probabilistic logic formalism, called CHRiSM, based on a combination of CHR and PRISM. It can be used for high-level rapid prototyping of complex statistical models by means of "chance rules". The underlying PRISM system can then be used for several probabilistic inference tasks, including probability computation and parameter learning. We define the CHRiSM language in terms of syntax and operational semantics, and illustrate it with examples. We define the notion of ambiguous programs and define a distribution semantics for unambiguous programs. Next, we describe an implementation of CHRiSM, based on CHR(PRISM). We discuss the relation between CHRiSM and other probabilistic logic programming languages, in particular PCHR. Finally we identify ...

  10. Comparing the Volumes of Rectangular Prisms

    Science.gov (United States)

    Assuah, Charles K.; Wiest, Lynda R.

    2010-01-01

    Can middle-grades students determine which of two rectangular prisms has a larger volume? Can they do so without using a formula? Geometry, and particularly the concept of volume, is important in many subjects, such as physics and chemistry. Students greatly enhance their mathematics knowledge when they make generalizations and construct arguments…

  11. Prisms Throw Light on Developmental Disorders

    Science.gov (United States)

    Brookes, Rebecca L.; Nicolson, Roderick I.; Fawcett, Angela J.

    2007-01-01

    Prism adaptation, in which the participant adapts to prismatic glasses that deflect vision laterally, is a specific test of cerebellar function. Fourteen dyslexic children (mean age 13.5 years); 14 children with developmental coordination disorder (DCD): 6 of whom had comorbid dyslexia; and 12 control children matched for age and IQ underwent…

  12. Self-referenced prism deflection measurement schemes with microradian precision

    CERN Document Server

    Olson, R; Bergeson, S; Durfee, D S; Olson, Rebecca; Paul, Justin; Bergeson, Scott; Durfee, Dallin S.

    2005-01-01

    We have demonstrated several inexpensive methods which can be used to measure the deflection angles of prisms with microradian precision. The methods are self-referenced, using various reversals to achieve absolute measurements without the need of a reference prism or any expensive precision components other than the prisms under test. These techniques are based on laser interferometry and have been used in our lab to characterize parallel-plate beamsplitters, penta prisms, right angle prisms, and corner cube reflectors using only components typically available in an optics lab.

  13. Multivariable control for the PRISM ALMR

    International Nuclear Information System (INIS)

    This paper describes the application of state variable control design methods in the conceptual design of two key system level controllers in the PRISM ALMR. The PRISM plant concept consists of three power blocks, each made up of three identical reactors and steam generator modules connected to one turbine. Operation of these physically distributed systems is directed by a hierarchy of controllers at the system, power block, and plant levels. The system level controllers in this paper are the reactivity controllers for movement of the six control rods in each of the nine reactor modules, and the feedwater control of the three parallel steam generators in each of the three power blocks. 4 refs., 6 figs., 1 tab

  14. Update on Chagas' disease in Mexico

    Directory of Open Access Journals (Sweden)

    Dumonteil Eric

    1999-01-01

    Full Text Available Chagas' disease, caused by the protozoan parasite Trypanosoma cruzi, represents a major public health problem in most of the American continent. As transmission of the parasite is being interrupted in most of South America, the disease remains endemic in various areas of Mexico. We review here some of the information gathered in recent years. Seroprevalence of T. cruzi infection in humans remains relatively high in some areas, and there has been a general increase in the number of chronic cases reported to health authorities in recent years. In fact, chronic chagasic cardiomyopathy appears to be affecting a large number of patients with heart disease, but many cases may be misreported because of the unspecific nature of the clinical symptoms. Epidemiological monitoring of vector and reservoir populations, as well as of human cases is helping focus on endemic areas, but a better coordination and development of these efforts is still needed. Recent studies of parasite biology are in agreement with previous work showing the great diversity of parasite characteristics, and support the need for a regional approach to this zoonosis. Strong and continuing support from health and academic authorities is thus still needed to further improve our understanding of Chagas' disease in Mexico and implement efficient control programs.

  15. Chagas disease and globalization of the Amazon.

    Science.gov (United States)

    Briceño-León, Roberto

    2007-01-01

    The increasing number of autochthonous cases of Chagas disease in the Amazon since the 1970s has led to fear that the disease may become a new public health problem in the region. This transformation in the disease's epidemiological pattern in the Amazon can be explained by environmental and social changes in the last 30 years. The current article draws on the sociological theory of perverse effects to explain these changes as the unwanted result of the shift from the "inward" development model prevailing until the 1970s to the "outward" model that we know as globalization, oriented by industrial forces and international trade. The current article highlights the implementation of five new patterns in agriculture, cattle-raising, mining, lumbering, and urban occupation that have generated changes in the environment and the traditional indigenous habitat and have led to migratory flows, deforestation, sedentary living, the presence of domestic animals, and changes in the habitat that facilitate colonization of human dwellings by vectors and the domestic and work-related transmission of the disease. The expansion of Chagas disease is thus a perverse effect of the globalization process in the Amazon. PMID:17308715

  16. Prisms to Shift Pain Away: Pathophysiological and Therapeutic Exploration of CRPS with Prism Adaptation

    Science.gov (United States)

    Volckmann, Pierre; Jacquin-Courtois, Sophie

    2016-01-01

    Complex Regional Pain Syndrome (CRPS) is an invalidating chronic condition subsequent to peripheral lesions. There is growing consensus for a central contribution to CRPS. However, the nature of this central body representation disorder is increasingly debated. Although it has been repeatedly argued that CRPS results in motor neglect of the affected side, visual egocentric reference frame was found to be deviated toward the pain, that is, neglect of the healthy side. Accordingly, prism adaptation has been successfully used to normalize this deviation. This study aimed at clarifying whether 7 CRPS patients exhibited neglect as well as exploring the pathophysiological mechanisms of this manifestation and of the therapeutic effects of prism adaptation. Pain and quality of life, egocentric reference frames (visual and proprioceptive straight-ahead), and neglect tests (line bisection, kinematic analyses of motor neglect and motor extinction) were repeatedly assessed prior to, during, and following a one-week intense prism adaptation intervention. First, our results provide no support for visual and motor neglect in CRPS. Second, reference frames for body representations were not systematically deviated. Third, intensive prism adaptation intervention durably ameliorated pain and quality of life. As for spatial neglect, understanding the therapeutic effects of prism adaptation deserves further investigations. PMID:27668094

  17. Evaluations of 1990 PRISM design revisions

    Energy Technology Data Exchange (ETDEWEB)

    Van Tuyle, G.J.; Slovik, G.C.; Chan, B.C.; Aronson, A.L.; Kennett, R.J. [Brookhaven National Lab., Upton, NY (United States)

    1992-03-01

    Analyses of the 1990 version of the PRISM Advanced Liquid Metal Reactor (ALMR) design are presented and discussed. Most of the calculations were performed using BNL computer codes, particularly SSC and MINET. In many cases, independent BNL calculations were compared against analyses presented by General Electric when they submitted the PRISM design revisions for evaluation by the Nuclear Regulatory Commission (NRC). The current PRISM design utilizes the metallic fuel developed by Argonne National Laboratory (ANL) which facilitates the passive/``inherent`` shutdown mechanism that acts to shut down reactor power production whenever the system overheats. There are a few vulnerabilities in the passive shutdown, with the most worrisome being the positive feedback from sodium density decreases or sodium voiding. Various postulated unscrammed events were examined by GE and/or BNL, and much of the analysis discussed in this report is focused on this category of events. For the most part, the BNL evaluations confirm the information submitted by General Electric. The principal areas of concern are related to the performance of the ternary metal fuel, and may be resolved as ANL continues with its fuel development and testing program.

  18. The noble enigma: Chagas' nominations for the Nobel Prize

    Directory of Open Access Journals (Sweden)

    Coutinho Marilia

    1999-01-01

    Full Text Available Carlos Chagas, a Brazilian physician, discovered the American trypanosomiasis in 1909. Like other remarkable discoveries of those days, his work helped to articulate the insect-vector theory and other theoretical guidelines in tropical medicine. Unlike all other discoveries, all the stages of this work were accomplished in a few months and by a single man. Chagas' discovery was widely recognized at home and abroad. He was twice nominated for the Nobel Prize - in 1913 and in 1921-, but never received the award. Evidence suggests that the reasons for this failure are related to the violent opposition that Chagas faced in Brazil. The contentions towards Chagas were related to a rejection of the meritocratic procedures that gave him prominence, as well as to local petty politics.

  19. PRogram In Support of Moms (PRISM): Development and Beta Testing.

    Science.gov (United States)

    Byatt, Nancy; Pbert, Lori; Hosein, Safiyah; Swartz, Holly A; Weinreb, Linda; Allison, Jeroan; Ziedonis, Douglas

    2016-08-01

    Most women with perinatal depression do not receive depression treatment. The authors describe the development and beta testing of a new program, PRogram In Support of Moms (PRISM), to improve treatment of perinatal depression in obstetric practices. A multidisciplinary work group of seven perinatal and behavioral health professionals was convened to design, refine, and beta-test PRISM in an obstetric practice. Iterative feedback and problem solving facilitated development of PRISM components, which include provider training and a toolkit, screening procedures, implementation assistance, and access to immediate psychiatric consultation. Beta testing with 50 patients over two months demonstrated feasibility and suggested that PRISM may improve provider screening rates and self-efficacy to address depression. On the basis of lessons learned, PRISM will be enhanced to integrate proactive patient engagement and monitoring into obstetric practices. PRISM may help overcome patient-, provider-, and system-level barriers to managing perinatal depression in obstetric settings. PMID:27079994

  20. The noble enigma: Chagas' nominations for the Nobel Prize

    OpenAIRE

    Marilia Coutinho; Olival Freire Jr.; João Carlos Pinto Dias

    1999-01-01

    Carlos Chagas, a Brazilian physician, discovered the American trypanosomiasis in 1909. Like other remarkable discoveries of those days, his work helped to articulate the insect-vector theory and other theoretical guidelines in tropical medicine. Unlike all other discoveries, all the stages of this work were accomplished in a few months and by a single man. Chagas' discovery was widely recognized at home and abroad. He was twice nominated for the Nobel Prize - in 1913 and in 1921-, but never r...

  1. Prophylactic and therapeutic DNA vaccines against Chagas disease

    OpenAIRE

    Arce-Fonseca, Minerva; Rios-Castro, Martha; Carrillo-Sánchez, Silvia del Carmen; Martínez-Cruz, Mariana; Rodríguez-Morales, Olivia

    2015-01-01

    Chagas disease is a zoonosis caused by Trypanosoma cruzi in which the most affected organ is the heart. Conventional chemotherapy has a very low effectiveness; despite recent efforts, there is currently no better or more effective treatment available. DNA vaccines provide a new alternative for both prevention and treatment of a variety of infectious disorders, including Chagas disease. Recombinant DNA technology has allowed some vaccines to be developed using recombinant proteins or virus-lik...

  2. A Multi-disciplinary Overview of Chagas in Periurban Peru

    Directory of Open Access Journals (Sweden)

    Sarah McCune

    2010-04-01

    Full Text Available There are between 8 and 11 million cases of America Human Trypanosomiasis, commonly known as Chagas disease, in Latin America. Chagas is endemic in southern Peru, especially the Arequipa region, where it has expanded from poor, rural areas to periurban communities. This paper summarizes the findings of four studies in periurban Arequipa: on determinants of disease-vector infestation; on prevalence, spatial patterns, and risk factors of Chagas; on links between migration, settlement patterns, and disease-vector infestation; and on the relationship between discordant test results and spatially clustered transmission hotspots. These studies identified two risk factors associated with the disease: population dynamics and the urbanization of poverty. Understanding the disease within this new urban context will allow for improved public health prevention efforts and policy initiatives. Discovered in 1909 by Brazilian physician Carlos Chagas, American Human Trypanosomiasis is a chronic and potentially life-threatening illness found throughout Latin America (Moncayo, 2003. Indeed, it is estimated that there are between 8 and 11 million cases in Mexico and Central and South America (Centers for Disease Control [CDC], 2009. Chagas disease, as it is most commonly known, is endemic in southern Peru, especially in the region of Arequipa. Once thought to be limited to poor, rural areas, the disease is now appearing in the periurban communities that surround Arequipa City, the capital of the region (Cornejo del Carpio, 2003. Understanding the urbanization of Chagas disease will allow public health and medical professionals to better combat the further transmission of the disease. After providing an overview of Chagas and introducing the scope of the disease in Latin America, this paper will summarize the findings of four recent studies conducted in periurban districts in Arequipa. Ultimately, this paper seeks to identify the risk factors associated with Chagas

  3. Biologic and Genetics Aspects of Chagas Disease at Endemic Areas

    OpenAIRE

    Marilanda Ferreira Bellini; Rosana Silistino-Souza; Marileila Varella-Garcia; Maria Tercília Vilela Azeredo-Oliveira; Ana Elizabete Silva

    2012-01-01

    The etiologic agent of Chagas Disease is the Trypanosoma cruzi, transmitted through blood-sucking insect vectors of the Triatominae subfamily, representing one of the most serious public health concerns in Latin America. There are geographic variations in the prevalence of clinical forms and morbidity of Chagas disease, likely due to genetic variation of the T. cruzi and the host genetic and environmental features. Increasing evidence has supported that inflammatory cytokines and chemokines a...

  4. Optimized design of parallel beam-splitting prism

    Institute of Scientific and Technical Information of China (English)

    Peitao Zhao(赵培涛); Guohua Li(李国华)

    2004-01-01

    A large lateral shearing distance of parallel beam-splitting prism is often needed in laser modulation and polarization interference. In this letter, we present an optimized design of parallel beam-splitting prism and list some different cases in detail. The optimized design widens the use range of parallel beam-splitting prism. At the wavelength of 632.8 nm, the law that the enlargement ratio changes with the refractive index and the apex angle is verified.

  5. Pure rotation of a prism on a ramp

    OpenAIRE

    Zhao, Zhen; Liu, Caishan; Ma, Daolin

    2014-01-01

    In this work, we study a prism with a cross section in polygon rolling on a ramp inclined at a small angle. The prism under gravity rolls purely around each individual edge, intermittently interrupted by a sequence of face collisions between the side face of the prism and the ramp. By limiting the prism in a planar motion, we propose a mathematical model to deal with the events of the impacts. With a pair of laser-Doppler vibrometers, experiments are also conducted to measure the motions of v...

  6. Wollaston prism phase-stepping point diffraction interferometer and method

    Science.gov (United States)

    Rushford, Michael C.

    2004-10-12

    A Wollaston prism phase-stepping point diffraction interferometer for testing a test optic. The Wollaston prism shears light into reference and signal beams, and provides phase stepping at increased accuracy by translating the Wollaston prism in a lateral direction with respect to the optical path. The reference beam produced by the Wollaston prism is directed through a pinhole of a diaphragm to produce a perfect spherical reference wave. The spherical reference wave is recombined with the signal beam to produce an interference fringe pattern of greater accuracy.

  7. The Variprism: A Large-Range Variable Prism for Measurement of the Angle of Squint

    OpenAIRE

    Simonsz, Huib

    1988-01-01

    textabstractPrism bars and variable Herschel prisms are most commonly used today to measure the angle of squint. Both have drawbacks, however. Prism bars are too large to carry around all day and are usually limited to 40 prism diopters (PD), while variable Herschel prisms have even smaller ranges. Hans Meester and I have therefore developed, at the Netherlands Ophthalmic Research Institute, Amsterdam, a hand-held prism that is continuously variable over a large range, horizontally as well as...

  8. Identifying Codes in the Complementary Prism of Cycles

    OpenAIRE

    Cappelle, Marcia R.; Coelho, Erika M. M.; Coelho, Hebert; Penso, Lucia D.; Rautenbach, Dieter

    2015-01-01

    We show that an identifying code of minimum order in the complementary prism of a cycle of order $n$ has order $7n/9+\\Theta(1)$. Furthermore, we observe that the clique-width of the complementary prism of a graph of clique-width $k$ is at most $4k$, and discuss some algorithmic consequences.

  9. A Study of the PDGF Signaling Pathway with PRISM

    OpenAIRE

    Qixia Yuan; Jun Pang; Sjouke Mauw; Panuwat Trairatphisan; Monique Wiesinger; Thomas Sauter

    2011-01-01

    In this paper, we apply the probabilistic model checker PRISM to the analysis of a biological system -- the Platelet-Derived Growth Factor (PDGF) signaling pathway, demonstrating in detail how this pathway can be analyzed in PRISM. We show that quantitative verification can yield a better understanding of the PDGF signaling pathway.

  10. New Light on a Prism: The Concert for All Reasons

    Science.gov (United States)

    Linaberry, Robin

    2004-01-01

    The prism concert concept was introduced in this country at the Eastman School of Music in 1975. The development of Eastman's inaugural prism concert is commonly attributed to Donald Hunsberger and Gustav Meier, conductors of the wind ensemble and orchestra, respectively. The basic idea is that different styles of music performed by different…

  11. Electric Field Enhancement of Nano Gap of Silver Prisms

    Institute of Scientific and Technical Information of China (English)

    KENZO Yamaguchi; TOMOHIRO Inoue; MASAMITSU Fujii; MASANOBU Haraguchi; TOSHIHIRO Okamoto; MASUO Fukui; SHU Seki; SEIICHI Tagawa

    2007-01-01

    Using numerical calculation, we examine the effects of gap distance of a pair of nano gap silver prisms with rounded corners on the local light intensity enhancement. Two peaks due to localized surface plasmon (LSP) excitation are observed in a wavelength range from 900nm to 300nm. The results demonstrate that peaks at a longer and a shorter wavelength corresponded to dipole-like and quadrupole-like LSP resonances, respectively. It is found that a gap distance up to 20nm provides larger light intensity enhancement than that of a single silver nano prism with rounded corners. Furthermore, nano gap silver prisms are fabricated by direct focused ion beam processing, and we measure the scattering light spectrum of a pair of nano prisms by a confocal optical system.However, the two LSP peaks are not observed in visible range because the sizes of the nano gap and prisms are too large.

  12. Chronic Chagas disease: from basics to laboratory medicine.

    Science.gov (United States)

    Haberland, Annekathrin; Saravia, Silvia Gilka Munoz; Wallukat, Gerd; Ziebig, Reinhard; Schimke, Ingolf

    2013-02-01

    Chagas disease, caused by Trypanosoma cruzi infection, is ranked as the most serious parasitic disease in Latin America and has huge potential to become a worldwide problem, due to increasing migration, and international tourism, as well as infectant transfer by blood contact and transfusion, intrauterine transfer, and organ transplantation. Nearly 30% of chronically-infected patients become symptomatic, often with a latency of 10-30 years, developing life-threatening complications. Of those, nearly 90% develop Chagas heart disease, while the others manifest gastrointestinal disease and neuronal disorders. Besides interrupting the infection cycle and chemo therapeutic infectant elimination, starting therapy early in symptomatic patients is important for counteracting the disease. This would be essentially supported by optimized patient management, involving risk assessment, early diagnosis and monitoring of the disease and its treatment. From economic and logistic viewpoints, the tools of laboratory medicine should be especially able to guarantee this. After summarizing the basics of chronic Chagas disease, such as the epidemiological data, the pathogenetic mechanisms thought to drive symptomatic Chagas disease and also treatment options, we present tools of laboratory medicine that address patient diagnosis, risk assessment for becoming symptomatic and guidance, focusing on autoantibody estimation for risk assessment and heart marker measurement for patient guidance. In addition, increases in levels of inflammation and oxidative stress markers in chronic Chagas disease are discussed.

  13. Active stereo vision routines using PRISM-3

    Science.gov (United States)

    Antonisse, Hendrick J.

    1992-11-01

    This paper describes work in progress on a set of visual routines and supporting capabilities implemented on the PRISM-3 real-time vision system. The routines are used in an outdoor robot retrieval task. The task requires the robot to locate a donor agent -- a Hero2000 -- which holds the object to be retrieved, to navigate to the donor, to accept the object from the donor, and return to its original location. The routines described here will form an integral part of the navigation and wide-area search tasks. Active perception is exploited to locate the donor using real-time stereo ranging directed by a pan/tilt/verge mechanism. A framework for orchestrating visual search has been implemented and is briefly described.

  14. Differential regional immune response in Chagas disease.

    Directory of Open Access Journals (Sweden)

    Juliana de Meis

    Full Text Available Following infection, lymphocytes expand exponentially and differentiate into effector cells to control infection and coordinate the multiple effector arms of the immune response. Soon after this expansion, the majority of antigen-specific lymphocytes die, thus keeping homeostasis, and a small pool of memory cells develops, providing long-term immunity to subsequent reinfection. The extent of infection and rate of pathogen clearance are thought to determine both the magnitude of cell expansion and the homeostatic contraction to a stable number of memory cells. This straight correlation between the kinetics of T cell response and the dynamics of lymphoid tissue cell numbers is a constant feature in acute infections yielded by pathogens that are cleared during the course of response. However, the regional dynamics of the immune response mounted against pathogens that are able to establish a persistent infection remain poorly understood. Herein we discuss the differential lymphocyte dynamics in distinct central and peripheral lymphoid organs following acute infection by Trypanosoma cruzi, the causative agent of Chagas disease. While the thymus and mesenteric lymph nodes undergo a severe atrophy with massive lymphocyte depletion, the spleen and subcutaneous lymph nodes expand due to T and B cell activation/proliferation. These events are regulated by cytokines, as well as parasite-derived moieties. In this regard, identifying the molecular mechanisms underlying regional lymphocyte dynamics secondary to T. cruzi infection may hopefully contribute to the design of novel immune intervention strategies to control pathology in this infection.

  15. A new era for chagas disease drug discovery?

    Science.gov (United States)

    Keenan, Martine; Chaplin, Jason H

    2015-01-01

    Recent clinical trials investigating treatment of chronic indeterminate Chagas disease with two re-purposed azole anti-fungal drugs, posaconazole and ravuconazole, revealed their inferiority to the current standard-of-care benznidazole and highlighted the inadequacy of the existing pre-clinical testing paradigm for this disease. A very limited number of controlled clinical trials for Chagas disease have been conducted to date. The selection of these compounds for clinical evaluation relied heavily on pre-clinical data obtained from in vitro screens and animal studies. This chapter reviews the evolution of CYP51 as a target for Trypanosoma cruzi growth inhibition and also explores the impact of clinical trial data on contemporary Chagas disease drug discovery. Advances in pre-clinical profiling assays, the current compound landscape and progress towards the identification of new drug targets to re-invigorate research are reviewed. PMID:25727705

  16. [Thermal spectral property of prism in hyper spectral imager].

    Science.gov (United States)

    Liang, Jiu-Sheng; Wu, Qing-Wen; Li, Ze-Xue; Chen, Li-Heng; Guo, Liang

    2010-06-01

    Prism is one of the most key parts in the hyper spectral imager (HSI). Consequently, to set thermal control target and make thermal control design, the thermal spectral property of prism in the HSI was studied. The working principle of the HSI and the definition of its thermal spectral property were introduced. The working environment of prism and its thermal effect were analyzed; also the study contents and technical route of the prism's thermal spectral property were discussed. The effects of different uniform temperature field on deflexion angle and angular dispersion of the prism in the HSI were deduced, and the changes in displacement of the spectra and the spectral bandwidth under different uniform temperature were obtained. For one instance, the thermal spectral property of the K9 prism and the fused silica prism were compared based on FEM and combined experiments, furthermore, its thermal control target was ascertained and a thermal spectral property test was carried out to validate the rationality of the thermal spectral property analysis. The results of analysis indicated that the changes in spectral bandwidth and spectrum resolution brought by thermal distortions can be ignored according to current fixing mode, and the displacement of the spectra is mainly determined by thermal coefficient of material refractive index; because of it's the lower thermal coefficient of material refractive index, the displacement of the spectra of the K9 prism is smaller under the same temperature changes; the material deflexion changes (dn/dlambda) of prism are not sensitive to the temperature, so the changes in spectral bandwidth caused by them are not obvious. And the results of test proved that the studied method of thermal spectral property is reasonable and essential, and the results are authentic and credible. So it can provide some guidance for setting thermal control target and optimizing thermal control design. PMID:20707180

  17. Aspectos neurológicos da moléstia de chagas Neurological aspects of Chagas disease

    Directory of Open Access Journals (Sweden)

    Fritz Köberle

    1967-09-01

    Full Text Available Carlos Chagas related in more than two 200 cases, what he called "nervous forms" of trypanosomiasis, that is neurological manifestations from central origin (idiotism, infantilism, pseudo-bulbar paralysis, aphasia, cerebellar ataxia, atetosis, espostic or paralytic diplegia, disbasia. At that time Chagas expressed his concepts as follows: "In relation to the frequency of trypanosomiasis nervous forms we have performed many observations which allow us to state that this disease is the one which causes the largest number of organic affections of the central nervous system, in human pathology". We are plenty convinced by Chagas's statement. By experiments on animals of laboratory we have very often noticed a rather varied neurological symptomatology, being worth point out identical syndromes to those observed by Chagas. Our autopsy material non-rarely include chronic Chagas cases presenting a most varied symtomatology. Among them we have named only three cases of discerebral nanism, a rather rare affection in other parts of the world and relatively frequent in our material. The fact which we have demonstrated, i.e., a relatively great decreasing of number of nervous cells in the peripheral system could happen in the central nervous system as well. Provided that there are only two quantitative works on neuron number diminishing in the central nervous system in mice and rats we decline to go into further details about central neuropathies in man. We emphasized the necessity to perform researches on this field by means of intimate collaboration between clinicians and pathologists, as the only way to confirm on scientific basis all that was observed by the panoramic and genial vision of Carlos Chagas.

  18. Recognizing Variable Environments The Theory of Cognitive Prism

    CERN Document Server

    Dong, Tiansi

    2012-01-01

    Normal adults do not have any difficulty in recognizing their homes. But can artificial systems do in the same way as humans? This book collects interdisciplinary evidences and presents an answer from the perspective of computing, namely, the theory of cognitive prism. To recognize an environment, an intelligent system only needs to classify objects, structures them based on the connection relation (not through measuring!), subjectively orders the objects, and compares with the target environment, whose knowledge is similarly structured. The intelligent system works, therefore, like a prism: when a beam of light (a scene) reaches (is perceived) to an optical prism (by an intelligent system), some light (objects) is reflected (are neglected), those passed through (the recognized objects) are distorted (are ordered differently). So comes the term 'cognitive prism'! Two fundamental propositions used in the theory can be informally stated as follow: an orientation relation is a kind of distance comparison relatio...

  19. Dynamics of a microliquid prism actuated by electrowetting.

    Science.gov (United States)

    Lee, Duck-Gyu; Park, Jaebum; Bae, Jungmok; Kim, Ho-Young

    2013-01-21

    A microliquid prism is a microchannel filled with two immiscible liquids, whose interface acts as a refractive surface. To steer a light beam that constructs optical images, the interface profile or the contact angle is modulated through electrowetting on a dielectric. Accurate, yet agile actuation of the liquid prism critically depends on the understanding of dynamics of the fluid interface. Here we fabricate liquid prisms, visualize the shape evolution of the interface, and theoretically model its dynamics. By comparing the magnitude of capillary forces to those of viscous, inertial and hydrostatic forces, we find that the meniscus motion within submillimetric channels is dominated by the capillary effect. The theoretical predictions for microscale meniscus dynamics are shown to agree well with the experimental measurements. We then discuss the formation of waves in millimetric liquid prisms, which may significantly limit fast and reliable operation of the optofluidic device. PMID:23165931

  20. Mining the Digital Hamburg/ESO Objective Prism Survey

    OpenAIRE

    Christlieb, N.; Wisotzki, L.; Reimers, D.

    2000-01-01

    We report on the exploitation of the stellar content of the Hamburg/ESO objective prism survey by quantitative selection methods, such as automatic spectral classification, and first results obtained.

  1. Doença de Chagas no Brasil Chagas disease in Brazil

    Directory of Open Access Journals (Sweden)

    Márcio C. Vinhaes

    2000-01-01

    Full Text Available Sumariam-se os dados da Fundação Nacional de Saúde (FNS sobre o estado atual dos vetores da doença de Chagas no Brasil, verificando-se que após vinte anos de controle químico continuado houve franca redução dos índices triatomínico-tripanosômicos, particularmente para esp��cies como Triatoma infestans e Panstrongylus megistus. Em paralelo, dados de sorologia escolar, de internações e de mortalidade pela doença indicam descenso nas taxas de incidência e impacto médico social da protozoose, restando áreas mais preocupantes, como o Nordeste e resíduos de T. infestans. Impõe-se urgente uma vigilância epidemiológica efetiva, a ser realizada por estados e municípios ante o processo de descentralização da FNS.This article presents the current situation for Chagas disease vectors in Brazil, based on data from the Brazilian National Health Foundation (FNS. Over the course of the last 20 years, continuous chemical control has resulted in a clear reduction of triatomine densities and Trypanosoma cruzi in Brazilian dwellings. Results have been particularly promising in relation to Triatoma infestans and Panstrongylus megistus, considered the most important species in the past. In parallel, data from school serological surveys, hospitalized patients, and mortality records show an important decrease in the disease. Nevertheless, some areas of the Brazilian Northeast and some residual foci of Triatoma infestans and Panstrongylus megistus remain as major challenges for public health authorities, requiring effective epidemiological surveillance. States and municipalities are required to assume this task at present, as the traditional Brazilian National Health Foundation is undergoing decentralization.

  2. Tricapped trigonal prism in crystal chemistry of oxygen lanthanide compounds

    International Nuclear Information System (INIS)

    It is shown that in the course of fragmentation of extreme coordination (CP)-icosahedron- 1 9-atom fragment (broken piece) appears to be one of the stages. Minimal transformations turn this 9-atom fragment into a tricapped trigonal prism. The latter represents the only extreme CP, which is built by monodentate acidoanions for the elements of the whole rare earth series. Statistic analysis of Ln-O interatomic distances in tricapped trigonal prisms is performed

  3. Spatial compression impairs prism-adaptation in healthy individuals

    OpenAIRE

    Roger Newport

    2013-01-01

    Neglect patients typically present with gross inattention to one side of space following damage to the contralateral hemisphere. While prism-adaptation is effective in ameliorating some neglect behaviours, the mechanisms involved and their relationship to neglect remain unclear. Recent studies have shown that conscious strategic control processes in prism-adaptation may be impaired in neglect patients, who are also reported to show extraordinarily long aftereffects compared to healthy partici...

  4. Random Prism: a noise-tolerant alternative to Random Forests

    OpenAIRE

    Stahl, Frederic; Bramer, Max

    2014-01-01

    Ensemble learning can be used to increase the overall classification accuracy of a classifier by generating multiple base classifiers and combining their classification results. A frequently used family of base classifiers for ensemble learning are decision trees. However, alternative approaches can potentially be used, such as the Prism family of algorithms that also induces classification rules. Compared with decision trees, Prism algorithms generate modular classification rules that cannot...

  5. Wedge Prism for Direction Resolved Speckle Correlation Interferometry

    International Nuclear Information System (INIS)

    The role of a wedge prism for strain sign determination and enhancing the sensitivity for sub-fringe changes is emphasized. The design and incorporation aspects for in-plane sensitive interferometers have been described in detail. Some experimental results dealing with stress determination by laser annealing and speckle correlation interferometry are presented. The prism can also be applied to produce standardized carrier fringes in spatial phase shifting interferometry

  6. Actinide recycle utilizing oxide and metallic fuel in prism

    International Nuclear Information System (INIS)

    PRISM is a modular, pool-type sodium-cooled fast reactor employing innovative, passive features to provide an extremely high level of public safety. The PRISM reactor design can accommodate both oxide and metallic fuel forms. A comparison of core design and performance of these forms is made for various options. These options include low fuel cycle cost options, maximum transuranic burning options, and the addition of rare earth elements to the fuel mix. (authors)

  7. Enfermedad de Chagas congenita en la Ciudad de Salta, Argentina Congenital Chagas' disease in Salta, Argentina

    Directory of Open Access Journals (Sweden)

    Mario Zaidenberg

    1993-02-01

    Full Text Available Se estudió la respuesta clínica y serológica a la infección chagásica de 937 embarazadas y sus 929 recién nacidos (RN vivos, grupo I; 4 RN de origen diverso, grupo II y 35 RN derivados de otros centros, grupo III. Las embarazadas se estudiaron con 3 reacciones serológicas; se definió infección cuando 2 o más reacciones eran positivas. En los RN el diagnóstico se confirmó por observación directa del T. cruzi en una muestra de sangre. Los RN con Chagas congénita (RN-ChC fueron tratados y seguidos con estudios clínicos y de laboratorio. Se detectaron 149 embarazadas chagásicas (15.9%, de las cuales se diagnosticaron 6 RN-ChC (4%. En el total de 968 RN estudiados se detectaron 12 RN infectados. El micro-hematócrito fue el método parasitológico de lectura rápida más efectivo para el diagnóstico de infección en nuestra serie. El par de reacciones serológicas específicas constituyó un criterio de mayor seguridad para el control y seguimiento de la infección congénita. Las expresiones clínicas más comunes de infección fueron hepatomegalia, esplenomegalia, ictericia, anemia y prematurez, con distintos grados de asociación. Se concluye que dadas las características clínicas de la enfermedad de Chagas congénita en nuestro medio, se impone como estrategia el diagnóstico serológico para la enfermedad de Chagas en todas las embarazadas y el control y seguimiento de sus RN hasta descartar o confirmar infección congénita.The immune response to Trypanosoma cruzi was studied in our hospital in 937 pregnant women (PW and their 929 newborns (NB, group I; 4 NB from this center not included in the first group, group II and 35 NB derived from other centers, group III. Two positive results among indirect hemagglutination (IHA, complement fixation (CF and indirect hemagglutination (IHA, complement fixation (CF and indirect immunofluorescence (IIF tests were considered as the criterion of previous infection with T. cruzi in PW. The

  8. Experimental Vaccines against Chagas Disease: A Journey through History.

    Science.gov (United States)

    Rodríguez-Morales, Olivia; Monteón-Padilla, Víctor; Carrillo-Sánchez, Silvia C; Rios-Castro, Martha; Martínez-Cruz, Mariana; Carabarin-Lima, Alejandro; Arce-Fonseca, Minerva

    2015-01-01

    Chagas disease, or American trypanosomiasis, which is caused by the protozoan parasite Trypanosoma cruzi, is primarily a vector disease endemic in 21 Latin American countries, including Mexico. Although many vector control programs have been implemented, T. cruzi has not been eradicated. The development of an anti-T. cruzi vaccine for prophylactic and therapeutic purposes may significantly contribute to the transmission control of Chagas disease. Immune protection against experimental infection with T. cruzi has been studied since the second decade of the last century, and many types of immunogens have been used subsequently, such as killed or attenuated parasites and new DNA vaccines. This primary prevention strategy appears feasible, effective, safe, and inexpensive, although problems remain. The objective of this review is to summarize the research efforts about the development of vaccines against Chagas disease worldwide. A thorough literature review was conducted by searching PubMed with the terms "Chagas disease" and "American trypanosomiasis" together with "vaccines" or "immunization". In addition, reports and journals not cited in PubMed were identified. Publications in English, Spanish, and Portuguese were reviewed.

  9. Experimental Vaccines against Chagas Disease: A Journey through History

    Directory of Open Access Journals (Sweden)

    Olivia Rodríguez-Morales

    2015-01-01

    Full Text Available Chagas disease, or American trypanosomiasis, which is caused by the protozoan parasite Trypanosoma cruzi, is primarily a vector disease endemic in 21 Latin American countries, including Mexico. Although many vector control programs have been implemented, T. cruzi has not been eradicated. The development of an anti-T. cruzi vaccine for prophylactic and therapeutic purposes may significantly contribute to the transmission control of Chagas disease. Immune protection against experimental infection with T. cruzi has been studied since the second decade of the last century, and many types of immunogens have been used subsequently, such as killed or attenuated parasites and new DNA vaccines. This primary prevention strategy appears feasible, effective, safe, and inexpensive, although problems remain. The objective of this review is to summarize the research efforts about the development of vaccines against Chagas disease worldwide. A thorough literature review was conducted by searching PubMed with the terms “Chagas disease” and “American trypanosomiasis” together with “vaccines” or “immunization”. In addition, reports and journals not cited in PubMed were identified. Publications in English, Spanish, and Portuguese were reviewed.

  10. Chagas cardiomyopathy in the context of the chronic disease transition.

    Directory of Open Access Journals (Sweden)

    Alicia I Hidron

    Full Text Available BACKGROUND: Patients with Chagas disease have migrated to cities, where obesity, hypertension and other cardiac risk factors are common. METHODOLOGY/PRINCIPAL FINDINGS: The study included adult patients evaluated by the cardiology service in a public hospital in Santa Cruz, Bolivia. Data included risk factors for T. cruzi infection, medical history, physical examination, electrocardiogram, echocardiogram, and contact 9 months after initial data collection to ascertain mortality. Serology and PCR for Trypanosoma cruzi were performed. Of 394 participants, 251 (64% had confirmed T. cruzi infection by serology. Among seropositive participants, 109 (43% had positive results by conventional PCR; of these, 89 (82% also had positive results by real time PCR. There was a high prevalence of hypertension (64% and overweight (body mass index [BMI] >25; 67%, with no difference by T. cruzi infection status. Nearly 60% of symptomatic congestive heart failure was attributed to Chagas cardiomyopathy; mortality was also higher for seropositive than seronegative patients (p = 0.05. In multivariable models, longer residence in an endemic province, residence in a rural area and poor housing conditions were associated with T. cruzi infection. Male sex, increasing age and poor housing were independent predictors of Chagas cardiomyopathy severity. Males and participants with BMI Chagas cardiomyopathy remains an important cause of congestive heart failure in this hospital population, and should be evaluated in the context of the epidemiological transition that has increased risk of obesity, hypertension and chronic cardiovascular disease.

  11. Experimental Vaccines against Chagas Disease: A Journey through History

    Science.gov (United States)

    Rodríguez-Morales, Olivia; Monteón-Padilla, Víctor; Carrillo-Sánchez, Silvia C.; Rios-Castro, Martha; Martínez-Cruz, Mariana; Carabarin-Lima, Alejandro; Arce-Fonseca, Minerva

    2015-01-01

    Chagas disease, or American trypanosomiasis, which is caused by the protozoan parasite Trypanosoma cruzi, is primarily a vector disease endemic in 21 Latin American countries, including Mexico. Although many vector control programs have been implemented, T. cruzi has not been eradicated. The development of an anti-T. cruzi vaccine for prophylactic and therapeutic purposes may significantly contribute to the transmission control of Chagas disease. Immune protection against experimental infection with T. cruzi has been studied since the second decade of the last century, and many types of immunogens have been used subsequently, such as killed or attenuated parasites and new DNA vaccines. This primary prevention strategy appears feasible, effective, safe, and inexpensive, although problems remain. The objective of this review is to summarize the research efforts about the development of vaccines against Chagas disease worldwide. A thorough literature review was conducted by searching PubMed with the terms “Chagas disease” and “American trypanosomiasis” together with “vaccines” or “immunization”. In addition, reports and journals not cited in PubMed were identified. Publications in English, Spanish, and Portuguese were reviewed. PMID:26090490

  12. PRISM: a planned risk information seeking model.

    Science.gov (United States)

    Kahlor, LeeAnn

    2010-06-01

    Recent attention on health-related information seeking has focused primarily on information seeking within specific health and health risk contexts. This study attempts to shift some of that focus to individual-level variables that may impact health risk information seeking across contexts. To locate these variables, the researcher posits an integrated model, the Planned Risk Information Seeking Model (PRISM). The model, which treats risk information seeking as a deliberate (planned) behavior, maps variables found in the Theory of Planned Behavior (TPB; Ajzen, 1991) and the Risk Information Seeking and Processing Model (RISP; Griffin, Dunwoody, & Neuwirth, 1999), and posits linkages among those variables. This effort is further informed by Kahlor's (2007) Augmented RISP, the Theory of Motivated Information Management (Afifi & Weiner, 2004), the Comprehensive Model of Information Seeking (Johnson & Meischke, 1993), the Health Information Acquisition Model (Freimuth, Stein, & Kean, 1989), and the Extended Parallel Processing Model (Witte, 1998). The resulting integrated model accounted for 59% of the variance in health risk information-seeking intent and performed better than the TPB or the RISP alone. PMID:20512716

  13. k-Odd mean labeling of prism

    Directory of Open Access Journals (Sweden)

    B. Gayathri

    2015-03-01

    Full Text Available ‎A $(p‎,‎q$ graph $G$ is said to have a $k$-odd mean‎ ‎labeling $(k ge 1$ if there exists an injection $f‎ : ‎V‎ ‎to {0‎, ‎1‎, ‎2‎, ‎ldots‎, ‎2k‎ + ‎2q‎ - ‎3}$ such that the‎ ‎induced map $f^*$ defined on $E$ by $f^*(uv =‎ ‎leftlceil frac{f(u+f(v}{2}rightrceil$ is a‎ ‎bijection from $E$ to ${2k - ‎‎‎1‎, ‎2k‎ + ‎1‎, ‎2k‎ + ‎3‎, ‎ldots‎, ‎2‎ ‎k‎ + ‎2q‎ - ‎3}$‎. ‎A graph that admits $k$-odd mean‎ ‎labeling is called $k$-odd mean graph‎. ‎In this paper‎, ‎we investigate $k$-odd mean labeling of prism $C_m times‎ ‎P_n$‎.

  14. Negative Refraction experiments in Photonic Crystal prisms

    Science.gov (United States)

    Vodo, Plarenta; Parimi, Patanjali. V.; Lu, Wentao. T.; di Gennaro, Emiliano; Sridhar, Srinivas

    2004-03-01

    We have experimentally demonstrated negative refraction in metallic photonic crystal (PC) prisms [1]. The refracted fields in the parallel plate waveguide (PPW) are measured by an automated dipole antenna, which scans the desired area, while the free space (FS) measurements, performed in a anechoic chamber, are measured by a rectangular X-band horn that swings in an arc in far field area. Both TE and TM excitation modes are used in FS experiments. Numerical calculations of the band structure and equi-frequency surface simulations are used to determine frequency regions of negative refraction of the triangular lattice PC. Angle of refraction determined by theoretical simulations and experimental results, are in exceptional good agreement, yielding the negative refraction index. FS and PPW refraction experimental results agree remarkably with simulations. 1. "Negative Refraction and Left-handed electromagnetism in Microwave Photonic Crystals", P.V Parimi, W.T Lu, P.Vodo J. Sokoloff and S.Sridhar, cond-mat/0306109 (2003)

  15. APEX - the Hyperspectral ESA Airborne Prism Experiment

    Directory of Open Access Journals (Sweden)

    Koen Meuleman

    2008-10-01

    Full Text Available The airborne ESA-APEX (Airborne Prism Experiment hyperspectral mission simulator is described with its distinct specifications to provide high quality remote sensing data. The concept of an automatic calibration, performed in the Calibration Home Base (CHB by using the Control Test Master (CTM, the In-Flight Calibration facility (IFC, quality flagging (QF and specific processing in a dedicated Processing and Archiving Facility (PAF, and vicarious calibration experiments are presented. A preview on major applications and the corresponding development efforts to provide scientific data products up to level 2/3 to the user is presented for limnology, vegetation, aerosols, general classification routines and rapid mapping tasks. BRDF (Bidirectional Reflectance Distribution Function issues are discussed and the spectral database SPECCHIO (Spectral Input/Output introduced. The optical performance as well as the dedicated software utilities make APEX a state-of-the-art hyperspectral sensor, capable of (a satisfying the needs of several research communities and (b helping the understanding of the Earth’s complex mechanisms.

  16. Chagas disease: control, elimination and eradication. Is it possible?

    Directory of Open Access Journals (Sweden)

    Jose Rodrigues Coura

    2013-12-01

    Full Text Available From an epidemiological point of view, Chagas disease and its reservoirs and vectors can present the following characteristics: (i enzooty, maintained by wild animals and vectors, with broad occurrence from southern United States of America (USA to southern Argentina and Chile (42ºN 49ºS, (ii anthropozoonosis, when man invades the wild ecotope and becomes infected with Trypanosoma cruzi from wild animals or vectors or when the vectors and wild animals, especially marsupials, invade the human domicile and infect man, (iii zoonosis-amphixenosis and exchanged infection between animals and humans by domestic vectors in endemic areas and (iv zooanthroponosis, infection that is transmitted from man to animals, by means of domestic vectors, which is the rarest situation in areas endemic for Chagas disease. The characteristics of Chagas disease as an enzooty of wild animals and as an anthropozoonosis are seen most frequently in the Brazilian Amazon and in the Pan-Amazon region as a whole, where there are 33 species of six genera of wild animals: Marsupialia, Chiroptera, Rodentia, Edentata (Xenarthra, Carnivora and Primata and 27 species of triatomines, most of which infected with T. cruzi . These conditions place the resident populations of this area or its visitors - tourists, hunters, fishermen and especially the people whose livelihood involves plant extraction - at risk of being affected by Chagas disease. On the other hand, there has been an exponential increase in the acute cases of Chagas disease in that region through oral transmission of T. cruzi , causing outbreaks of the disease. In four seroepidemiological surveys that were carried out in areas of the microregion of the Negro River, state of Amazonas, in 1991, 1993, 1997 and 2010, we found large numbers of people who were serologically positive for T. cruzi infection. The majority of them and/or their relatives worked in piassava extraction and had come into contact with and were stung by

  17. Current drug therapy and pharmaceutical challenges for Chagas disease.

    Science.gov (United States)

    Bermudez, José; Davies, Carolina; Simonazzi, Analía; Real, Juan Pablo; Palma, Santiago

    2016-04-01

    One of the most significant health problems in the American continent in terms of human health, and socioeconomic impact is Chagas disease, caused by the protozoan parasite Trypanosoma cruzi. Infection was originally transmitted by reduviid insects, congenitally from mother to fetus, and by oral ingestion in sylvatic/rural environments, but blood transfusions, organ transplants, laboratory accidents, and sharing of contaminated syringes also contribute to modern day transmission. Likewise, Chagas disease used to be endemic from Northern Mexico to Argentina, but migrations have earned it global. The parasite has a complex life cycle, infecting different species, and invading a variety of cells - including muscle and nerve cells of the heart and gastrointestinal tract - in the mammalian host. Human infection outcome is a potentially fatal cardiomyopathy, and gastrointestinal tract lesions. In absence of a vaccine, vector control and treatment of patients are the only tools to control the disease. Unfortunately, the only drugs now available for Chagas' disease, Nifurtimox and Benznidazole, are relatively toxic for adult patients, and require prolonged administration. Benznidazole is the first choice for Chagas disease treatment due to its lower side effects than Nifurtimox. However, different strategies are being sought to overcome Benznidazole's toxicity including shorter or intermittent administration schedules-either alone or in combination with other drugs. In addition, a long list of compounds has shown trypanocidal activity, ranging from natural products to specially designed molecules, re-purposing drugs commercialized to treat other maladies, and homeopathy. In the present review, we will briefly summarize the upturns of current treatment of Chagas disease, discuss the increment on research and scientific publications about this topic, and give an overview of the state-of-the-art research aiming to produce an alternative medication to treat T. cruzi infection

  18. Chagas disease in a Texan horse with neurologic deficits.

    Science.gov (United States)

    Bryan, Laura K; Hamer, Sarah A; Shaw, Sarah; Curtis-Robles, Rachel; Auckland, Lisa D; Hodo, Carolyn L; Chaffin, Keith; Rech, Raquel R

    2016-01-30

    A 10-year-old Quarter Horse gelding presented to the Texas A&M University Veterinary Teaching Hospital with a six month-history of ataxia and lameness in the hind limbs. The horse was treated presumptively for equine protozoal myeloencephalitis (EPM) based on clinical signs but was ultimately euthanized after its condition worsened. Gross lesions were limited to a small area of reddening in the gray matter of the thoracic spinal cord. Histologically, trypanosome amastigotes morphologically similar to Trypanosoma cruzi, the agent of Chagas disease in humans and dogs, were sporadically detected within segments of the thoracic spinal cord surrounded by mild lymphoplasmacytic inflammation. Ancillary testing for Sarcocystis neurona, Neospora spp., Toxoplasma gondii and Leishmania spp. was negative. Conventional and real time polymerase chain reaction (PCR) of affected paraffin embedded spinal cord were positive for T. cruzi, and sequencing of the amplified T. cruzi satellite DNA PCR fragment from the horse was homologous with various clones of T. cruzi in GenBank. While canine Chagas disease cases have been widely reported in southern Texas, this is the first report of clinical T. cruzi infection in an equid with demonstrable amastigotes in the spinal cord. In contrast to previous instances of Chagas disease in the central nervous system (CNS) of dogs and humans, no inflammation or T. cruzi amastigotes were detected in the heart of the horse. Based on clinical signs, there is a potential for misdiagnosis of Chagas disease with other infectious diseases that affect the equine CNS. T. cruzi should be considered as a differential diagnosis in horses with neurologic clinical signs and histologic evidence of meningomyelitis that originate in areas where Chagas disease is present. The prevalence of T. cruzi in horses and the role of equids in the parasite life cycle require further study. PMID:26801589

  19. Does my patient have chronic Chagas disease? Development and temporal validation of a diagnostic risk score

    OpenAIRE

    Pedro Emmanuel Alvarenga Americano do Brasil; Sergio Salles Xavier; Marcelo Teixeira Holanda; Alejandro Marcel Hasslocher-Moreno; José Ueleres Braga

    2016-01-01

    Abstract: INTRODUCTION With the globalization of Chagas disease, unexperienced health care providers may have difficulties in identifying which patients should be examined for this condition. This study aimed to develop and validate a diagnostic clinical prediction model for chronic Chagas disease. METHODS This diagnostic cohort study included consecutive volunteers suspected to have chronic Chagas disease. The clinical information was blindly compared to serological tests results, and a ...

  20. Prism adaptation changes the subjective proprioceptive localization of the hands.

    Science.gov (United States)

    Scarpina, Federica; Van der Stigchel, Stefan; Nijboer, Tanja Cornelia Wilhelmina; Dijkerman, Hendrik Christiaan

    2015-03-01

    Prism adaptation involves a proprioceptive, a visual and a motor component. As the existing paradigms are not able to distinguish between these three components, the contribution of the proprioceptive component remains unclear. In the current study, a proprioceptive judgement task, in the absence of motor responses, was used to investigate how prism adaptation would specifically influences the felt position of the hands in healthy participants. The task was administered before and after adaptation to left and right displacing prisms using either the left or the right hand during the adaptation procedure. The results appeared to suggest that the prisms induced a drift in the felt position of the hands, although the after-effect depended on the combination of the pointing hand and the visual deviation induced by prisms. The results are interpreted as in line with the hypothesis of an asymmetrical neural architecture of somatosensory processing. Moreover, the passive proprioception of the hand position revealed different effects of proprioceptive re-alignment compared to active pointing straight ahead: different mechanisms about how visuo-proprioceptive discrepancy is resolved were hypothesized.

  1. Research on beam splitting prism in laser heterodyne interferometer

    Science.gov (United States)

    Fu, Xiu-hua; Xiong, Shi-fu; Kou, Yang; Pan, Yong-gang; Chen, Heng; Li, Zeng-yu; Zhang, Chuan-xin

    2014-08-01

    With the rapid development of optical testing technology, laser heterodyne interferometer has been used more and more widely. As the testing precision requirements continue to increase, the technical prism is an important component of heterodyne interference. The research utilizing thin film technology to improve optical performance of interferometer has been a new focus. In the article, based on the use requirements of interferometer beam splitting prism, select Ta2O5 and SiO2 as high and low refractive index materials respectively, deposit on substrate K9. With the help of TFCalc design software and Needle method, adopting electron gun evaporation and ion assisted deposition, the beam splitting prism is prepared successfully and the ratio of transmittance and reflectance for this beam splitting prism in 500~850 nm band, incident angle 45 degree is 8:2. After repeated tests, solved the difference problem of film deposition process parameters ,controlled thickness monitoring precision effectively and finally prepared the ideal beam splitting prism which is high adhesion and stable optics properties. The film the laser induced damage threshold and it meet the requirements of heterodyne interferometer for use.

  2. Study of dose calculation on breast brachytherapy using prism TPS

    Science.gov (United States)

    Fendriani, Yoza; Haryanto, Freddy

    2015-09-01

    PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm3. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm3. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy.

  3. Prism-based single-camera system for stereo display

    Science.gov (United States)

    Zhao, Yue; Cui, Xiaoyu; Wang, Zhiguo; Chen, Hongsheng; Fan, Heyu; Wu, Teresa

    2016-06-01

    This paper combines the prism and single camera and puts forward a method of stereo imaging with low cost. First of all, according to the principle of geometrical optics, we can deduce the relationship between the prism single-camera system and dual-camera system, and according to the principle of binocular vision we can deduce the relationship between binoculars and dual camera. Thus we can establish the relationship between the prism single-camera system and binoculars and get the positional relation of prism, camera, and object with the best effect of stereo display. Finally, using the active shutter stereo glasses of NVIDIA Company, we can realize the three-dimensional (3-D) display of the object. The experimental results show that the proposed approach can make use of the prism single-camera system to simulate the various observation manners of eyes. The stereo imaging system, which is designed by the method proposed by this paper, can restore the 3-D shape of the object being photographed factually.

  4. Reverse time migration of prism waves for salt flank delineation

    KAUST Repository

    Dai, Wei

    2013-09-22

    In this paper, we present a new reverse time migration method for imaging salt flanks with prism wave reflections. It consists of four steps: (1) migrating the seismic data with conventional RTM to give the RTM image; (2) using the RTM image as a reflectivity model to simulate source-side reflections with the Born approximation; (3) zero-lag correlation of the source-side reflection wavefields and receiver-side wavefields to produce the prism wave migration image; and (4) repeating steps 2 and 3 for the receiver-side reflections. An advantage of this method is that there is no need to pick the horizontal reflectors prior to migration of the prism waves. It also separately images the vertical structures at a different step to reduce crosstalk interference. The disadvantage of prism wave migration algorithm is that its computational cost is twice that of conventional RTM. The empirical results with a salt model suggest that prism wave migration can be an effective method for salt flank delineation in the absence of diving waves.

  5. Study of dose calculation on breast brachytherapy using prism TPS

    International Nuclear Information System (INIS)

    PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm3. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm3. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy

  6. Dissecting slander and crying for justice: Carlos Chagas and the Nobel Prize of 1921.

    Science.gov (United States)

    Bestetti, Reinaldo B; Cardinalli-Neto, Augusto

    2013-10-01

    Chagas disease was discovered by Carlos Chagas in 1909. Chagas worked at Oswaldo Cruz Institute, where the bases of experimental medicine were settled in Brazil, and that had no connection with the Faculty of Medicine of Rio de Janeiro. Chagas had several enemies at Oswaldo Cruz Institute mainly because of his election to Head of Service in 1910, and for the position of Oswaldo Cruz Directorship in 1917. Furthermore, Chagas gained enemies at Faculty of Medicine of Rio de Janeiro, which did not like to see the economical political autonomy of Oswaldo Cruz Institute. This allowed the Institute not only to perform top experimental research, but also to take the leadership of research in the country. Chagas was nominated to the Nobel Prize of 1921 in December, 1920. None was awarded the Nobel Prize in that year. He seems to have been evaluated by the Noble Committee of Karolinska Institute from March to May of 1921. At that time, his enemies were denying his discovery of Trypanosoma cruzi, a key point in Chagas' nomination by Karolinska Institute, and giving no epidemiological importance for the disease. By the same way, the obligation of small pox vaccination was tarnishing his public image. Having taken into account the epidemiologic importance of Chagas disease, the strong historical mistake in the process of Chagas evaluation, and the inequity behind all these facts, we insist on a posthumous Nobel Prize for the man who made the most complete medical-scientist discovery of all time. PMID:23410487

  7. Dissecting slander and crying for justice: Carlos Chagas and the Nobel Prize of 1921.

    Science.gov (United States)

    Bestetti, Reinaldo B; Cardinalli-Neto, Augusto

    2013-10-01

    Chagas disease was discovered by Carlos Chagas in 1909. Chagas worked at Oswaldo Cruz Institute, where the bases of experimental medicine were settled in Brazil, and that had no connection with the Faculty of Medicine of Rio de Janeiro. Chagas had several enemies at Oswaldo Cruz Institute mainly because of his election to Head of Service in 1910, and for the position of Oswaldo Cruz Directorship in 1917. Furthermore, Chagas gained enemies at Faculty of Medicine of Rio de Janeiro, which did not like to see the economical political autonomy of Oswaldo Cruz Institute. This allowed the Institute not only to perform top experimental research, but also to take the leadership of research in the country. Chagas was nominated to the Nobel Prize of 1921 in December, 1920. None was awarded the Nobel Prize in that year. He seems to have been evaluated by the Noble Committee of Karolinska Institute from March to May of 1921. At that time, his enemies were denying his discovery of Trypanosoma cruzi, a key point in Chagas' nomination by Karolinska Institute, and giving no epidemiological importance for the disease. By the same way, the obligation of small pox vaccination was tarnishing his public image. Having taken into account the epidemiologic importance of Chagas disease, the strong historical mistake in the process of Chagas evaluation, and the inequity behind all these facts, we insist on a posthumous Nobel Prize for the man who made the most complete medical-scientist discovery of all time.

  8. Interactive Media on Chagas Disease: Development and Content

    Directory of Open Access Journals (Sweden)

    Claudinei Caetano de Souza

    2013-10-01

    Full Text Available An interactive media on Chagas disease was developed as an educational tool, on the context of the scientific research and dissemination actions of the National Institute of Structural Biotechnology and Medicinal Chemistry in Infectious Diseases (INBEQMeDI. Different computational resources were used either in terms of hardware and software. The media contains 13 videos that range from 30 seconds to 4 minutes, all with information about Chagas disease, showing the social and economic aspects; the research made by the INBEQMeDI group; different aspects of the disease illustrated by slides arranged in a mobile carousel, and radio programs, with funny skits. The target audience for use of this feature is students aged 10 to 17 years. Teachers of areas of science and biology, through a partnership with the Agency of Education of the State of São Paulo, will be invited to plan a strategy for media use with their students.

  9. Distribution and characterization of canine Chagas disease in Texas.

    Science.gov (United States)

    Kjos, S A; Snowden, K F; Craig, T M; Lewis, B; Ronald, N; Olson, J K

    2008-04-15

    Although acute and chronic cases of canine Chagas disease have been reported from multiple areas in the southern region of the United States, little data are available on current disease occurrence patterns in endemic areas. Therefore, a study to assess frequency, geographic distribution, signalment, and clinical spectrum of Chagas disease in domestic dogs from Texas was conducted. Serology, histopathology, and clinical case records from multiple institutions for the time period 1993-2007 were analyzed. A total of 537 serologically and/or histopathologically confirmed cases were documented. Cases were reported from 48 of 254 counties within Texas, covering all major geographic regions. Forty-eight dog breeds were represented among the cases, primarily in the sporting and working groups. In histopathologically confirmed cases, acute death occurred in 42%, approximately half of which were ecoregions of Texas, affecting a broad range of dog breeds and age groups. PMID:18255233

  10. Advanced hyperspectral video imaging system using Amici prism.

    Science.gov (United States)

    Feng, Jiao; Fang, Xiaojing; Cao, Xun; Ma, Chenguang; Dai, Qionghai; Zhu, Hongbo; Wang, Yongjin

    2014-08-11

    In this paper, we propose an advanced hyperspectral video imaging system (AHVIS), which consists of an objective lens, an occlusion mask, a relay lens, an Amici prism and two cameras. An RGB camera is used for spatial reading and a gray scale camera is used for measuring the scene with spectral information. The objective lens collects more light energy from the observed scene and images the scene on an occlusion mask, which subsamples the image of the observed scene. Then, the subsampled image is sent to the gray scale camera through the relay lens and the Amici prism. The Amici prism that is used to realize spectral dispersion along the optical path reduces optical distortions and offers direct view of the scene. The main advantages of the proposed system are improved light throughput and less optical distortion. Furthermore, the presented configuration is more compact, robust and practicable. PMID:25321019

  11. The PRISM4 (mid-Piacenzian) paleoenvironmental reconstruction

    Science.gov (United States)

    Dowsett, Harry J.; Dolan, Aisling M.; Rowley, David; Moucha, Robert; Forte, Alessandro; Mitrovica, Jerry X.; Pound, Matthew; Salzmann, Ulrich; Robinson, Marci M.; Chandler, Mark; Foley, Kevin M.; Haywood, Alan M.

    2016-01-01

    The mid-Piacenzian is known as a period of relative warmth when compared to the present day. A comprehensive understanding of conditions during the Piacenzian serves as both a conceptual model and a source for boundary conditions as well as means of verification of global climate model experiments. In this paper we present the PRISM4 reconstruction, a paleoenvironmental reconstruction of the mid-Piacenzian ( ∼ 3 Ma) containing data for paleogeography, land and sea ice, sea-surface temperature, vegetation, soils, and lakes. Our retrodicted paleogeography takes into account glacial isostatic adjustments and changes in dynamic topography. Soils and lakes, both significant as land surface features, are introduced to the PRISM reconstruction for the first time. Sea-surface temperature and vegetation reconstructions are unchanged but now have confidence assessments. The PRISM4 reconstruction is being used as boundary condition data for the Pliocene Model Intercomparison Project Phase 2 (PlioMIP2) experiments.

  12. Interpretation of the Faust equation for a conventional refracting prism

    Science.gov (United States)

    Tewari, R. D.; Ghodgaonkar, A. M.; Gokhale, V. D.

    1995-10-01

    The Faust formula for a conventional refracting prism is interpreted in terms of the angle of incidence ( i1) and the angle of deviation (δ). Three new possibilities emerge, namely: (a) keeping the angle of incidence ( i1) constant and varying the angle of deviation (δ); (b) keeping the angle of deviation constant and varying the angle of incidence ( i1); (c) modification of the closed forms of Murty's expression and its equivalence to (b). Using paraxial approximation and keeping the angle of incidence ( i1) and angle of deviation (δ) constant we obtain a relation between the refractive index and the base length ( b) of a prism and, in principle, this is equivalent to the Marcuse variation for optical fibres. The condition for a Littrow prism, as well as for polarized radiation is derived. An expression to estimate the spectral bandwidth (SBW) of the instrument is also derived. Experimental values of refractive index at different wavelengths are within confidence limits.

  13. Nuclear medicine gamma camera system PRISM-XP series

    International Nuclear Information System (INIS)

    Recently, SPECT gamma camera systems have become important in RI imaging of the brain and torso. The PRISM-XP series is a new SPECT system which employs multiple detectors, a fan beam collimator and a non-circular orbit for improved acquisition speed and sensitivity. For improved data processing, this machine uses a 64-bit CPU and a 3D graphics subsystem specially designed for image processing. The PRISM-XP series also includes 3-detector, 2-detector and 1-detector systems. The dual and single detector systems also have functions for whole-body imaging. In this article, the PRISM-XP series, which is commercialized by PICKER International Inc, Ohio, U.S.A., is presented. (author)

  14. Prophylactic and therapeutic DNA vaccines against Chagas disease.

    Science.gov (United States)

    Arce-Fonseca, Minerva; Rios-Castro, Martha; Carrillo-Sánchez, Silvia del Carmen; Martínez-Cruz, Mariana; Rodríguez-Morales, Olivia

    2015-01-01

    Chagas disease is a zoonosis caused by Trypanosoma cruzi in which the most affected organ is the heart. Conventional chemotherapy has a very low effectiveness; despite recent efforts, there is currently no better or more effective treatment available. DNA vaccines provide a new alternative for both prevention and treatment of a variety of infectious disorders, including Chagas disease. Recombinant DNA technology has allowed some vaccines to be developed using recombinant proteins or virus-like particles capable of inducing both a humoral and cellular specific immune response. This type of immunization has been successfully used in preclinical studies and there are diverse models for viral, bacterial and/or parasitic diseases, allergies, tumors and other diseases. Therefore, several research groups have been given the task of designing a DNA vaccine against experimental infection with T. cruzi. In this review we explain what DNA vaccines are and the most recent studies that have been done to develop them with prophylactic or therapeutic purposes against Chagas disease.

  15. Chagas heart disease: pathophysiologic mechanisms, prognostic factors and risk stratification

    Directory of Open Access Journals (Sweden)

    Anis Rassi Jr

    2009-07-01

    Full Text Available Chagas heart disease (CHD results from infection with the protozoan parasite Trypanosoma cruzi and is the leading cause of infectious myocarditis worldwide. It poses a substantial public health burden due to high morbidity and mortality. CHD is also the most serious and frequent manifestation of chronic Chagas disease and appears in 20-40% of infected individuals between 10-30 years after the original acute infection. In recent decades, numerous clinical and experimental investigations have shown that a low-grade but incessant parasitism, along with an accompanying immunological response [either parasite-driven (most likely or autoimmune-mediated], plays an important role in producing myocardial damage in CHD. At the same time, primary neuronal damage and microvascular dysfunction have been described as ancillary pathogenic mechanisms. Conduction system disturbances, atrial and ventricular arrhythmias, congestive heart failure, systemic and pulmonary thromboembolism and sudden cardiac death are the most common clinical manifestations of chronic Chagas cardiomyopathy. Management of CHD aims to relieve symptoms, identify markers of unfavourable prognosis and treat those individuals at increased risk of disease progression or death. This article reviews the pathophysiology of myocardial damage, discusses the value of current risk stratification models and proposes an algorithm to guide mortality risk assessment and therapeutic decision-making in patients with CHD.

  16. Opportunity cost for early treatment of Chagas disease in Mexico.

    Directory of Open Access Journals (Sweden)

    Janine M Ramsey

    2014-04-01

    Full Text Available BACKGROUND: Given current neglect for Chagas disease in public health programs in Mexico, future healthcare and economic development policies will need a more robust model to analyze costs and impacts of timely clinical attention of infected populations. METHODOLOGY/PRINCIPAL FINDINGS: A Markov decision model was constructed to simulate the natural history of a Chagas disease cohort in Mexico and to project the associated short and long-term clinical outcomes and corresponding costs. The lifetime cost for a timely diagnosed and treated Chagas disease patient is US$ 10,160, while the cost for an undiagnosed individual is US$ 11,877. The cost of a diagnosed and treated case increases 24-fold from early acute to indeterminate stage. The major cost component for lifetime cost was working days lost, between 44% and 75%, depending on the program scenario for timely diagnosis and treatment. CONCLUSIONS/SIGNIFICANCE: In the long term, it is cheaper to diagnose and treat chagasic patients early, instead of doing nothing. This finding by itself argues for the need to shift current policy, in order to prioritize and attend this neglected disease for the benefit of social and economic development, which implies including treatment drugs in the national formularies. Present results are even more relevant, if one considers that timely diagnosis and treatment can arrest clinical progression and enhance a chronic patient's quality of life.

  17. Methodological advances in drug discovery for Chagas disease

    Science.gov (United States)

    Bustamante, Juan M.; Tarleton, Rick L.

    2011-01-01

    Introduction Chagas disease is the highest impact human infectious disease in Latin America, and the leading worldwide cause of myocarditis. Despite the availability of several compounds that have demonstrated efficacy in limiting the effects of T. cruzi, these compounds are rarely used due to their variable efficacy, substantial side effects and the lack of methodologies for confirming their effectiveness. Furthermore, the development of more efficacious compounds is challenged by limitations of systems for assessing drug efficacy in vitro and in vivo. Areas covered Herein, the authors review the development of Chagas disease drug discovery methodology, focusing on recent developments in high throughput screening, in vivo testing methods and assessments of efficacy in humans. Particularly, this review documents the significant progress that has taken place over the last 5 years that have paved the way for both target-focused and high-throughput screens of compound libraries. Expert opinion The tools for in vitro and in vivo screening of anti-T. cruzi compounds have improved dramatically in the last few years and there are now a number of excellent in vivo testing models available; this somewhat alleviates the bottleneck issue of quickly and definitively demonstrating in vivo efficacy in a relevant host animal system. These advances emphasize the potential for additional progress resulting in new treatments for Chagas disease in the coming years. That being said, national and international agencies must improve the coordination of research and development efforts in addition to cultivating the funding sources for the development of these new treatments. PMID:21712965

  18. Scrutinizing the Biomarkers for the Neglected Chagas Disease: How Remarkable!

    Science.gov (United States)

    Pinho, Rosa T.; Waghabi, Mariana C.; Cardillo, Fabíola; Mengel, José; Antas, Paulo R. Z.

    2016-01-01

    Biomarkers or biosignature profiles have become accessible over time in population-based studies for Chagas disease. Thus, the identification of consistent and reliable indicators of the diagnosis and prognosis of patients with heart failure might facilitate the prioritization of therapeutic management to those with the highest chance of contracting this disease. The purpose of this paper is to review the recent state and the upcoming trends in biomarkers for human Chagas disease. As an emerging concept, we propose a classification of biomarkers based on plasmatic-, phenotype-, antigenic-, genetic-, and management-related candidates. The available data revisited here reveal the lessons learned thus far and the existing challenges that still lie ahead to enable biomarkers to be employed consistently in risk evaluation for this disease. There is a strong need for biomarker validation, particularly for biomarkers that are specific to the clinical forms of Chagas disease. The current failure to achieve the eradication of the transmission of this disease has produced determination to solve this validation issue. Finally, it would be strategic to develop a wide variety of biomarkers and to test them in both preclinical and clinical trials. PMID:27563302

  19. The Role of Haptoglobin Genotypes in Chagas Disease

    Science.gov (United States)

    Mundaray Fernández, Ninomar; Fernández-Mestre, Mercedes

    2014-01-01

    Although the number of people infected with T. cruzi is on the rise, host genetic and immune components that are crucial in the development of the Chagas disease have been discovered. We investigated the frequency of polymorphisms in the gene encoding haptoglobin of patients with chronic Chagas disease. The results suggest that while the HP1-1 genotype may confer protection against infection and the development of chronic Chagas disease due to the rapid metabolism of the Hp1-1-Hb complex and its anti-inflammatory activity, the presence of HP2-2 genotype may increase susceptibility towards a chronic condition of the disease due to a slow metabolism of the Hp2-2-Hb complex, lower antioxidant activity, and increased inflammatory reactivity, which lead to cell damage and a deterioration of the cardiac function. Finally, correlations between HP genotypes in different age groups and cardiac manifestations suggest that HP polymorphism could influence the prognosis of this infectious disease. This study shows some of the relevant aspects of the haptoglobin gene polymorphism and its implications in the T. cruzi infection. PMID:25147423

  20. The Role of Haptoglobin Genotypes in Chagas Disease

    Directory of Open Access Journals (Sweden)

    Ninomar Mundaray Fernández

    2014-01-01

    Full Text Available Although the number of people infected with T. cruzi is on the rise, host genetic and immune components that are crucial in the development of the Chagas disease have been discovered. We investigated the frequency of polymorphisms in the gene encoding haptoglobin of patients with chronic Chagas disease. The results suggest that while the HP1-1 genotype may confer protection against infection and the development of chronic Chagas disease due to the rapid metabolism of the Hp1-1-Hb complex and its anti-inflammatory activity, the presence of HP2-2 genotype may increase susceptibility towards a chronic condition of the disease due to a slow metabolism of the Hp2-2-Hb complex, lower antioxidant activity, and increased inflammatory reactivity, which lead to cell damage and a deterioration of the cardiac function. Finally, correlations between HP genotypes in different age groups and cardiac manifestations suggest that HP polymorphism could influence the prognosis of this infectious disease. This study shows some of the relevant aspects of the haptoglobin gene polymorphism and its implications in the T. cruzi infection.

  1. A Paratransgenic Strategy for the Control of Chagas Disease

    Directory of Open Access Journals (Sweden)

    Ivy Hurwitz

    2012-01-01

    Full Text Available Chagas disease results from infection with the parasite Trypanosoma cruzi. This disease remains a significant cause of morbidity and mortality in central and south America. Chagas disease now exists and is detected worldwide because of human migration. Control of Chagas disease has relied mainly on vector eradication however, the development of insect resistance to pesticides, coupled with cost and adverse health effects of insecticide treatments, has prompted our group to investigate novel methods of transmission control. Our laboratory has been instrumental in the development of the paratransgenic strategy to control vectorial transmission of T. cruzi. In this paper, we discuss various components of the paratransgenic approach. Specifically, we describe classes of molecules that can serve as effectors, including antimicrobial peptides, endoglucanases, and highly specific single chain antibodies that target surface glycoprotein tags on the surface of T. cruzi. Furthermore, we address evolving concepts related to field dispersal of engineered bacteria as part of the paratransgenic control strategy and attendant risk assessment evaluation.

  2. Transmission and Distribution of Optical Field in Prism Coupler

    International Nuclear Information System (INIS)

    Transmission and distribution characteristics of optical field in prism coupler are studies, and the phase matching function of prism coupler is deduced based on coupled wave theory. It is shown that the stable light field distribution and mode pattern are determined by its own geometric and dielectric parameters, but have nothing to do with the categories of incident light sources. It is also found that the coupling effect would generate between waveguides through evanescent field. Our numerical simulation is based on the finite difference time domain method with perfectly matched layer absorbing boundary condition. The simulation program is compiled in MATLAB. The simulation results are analyzed carefully.

  3. Temperature Influence on Divergence Angles of Quartz Crystal Wollaston Prism

    International Nuclear Information System (INIS)

    We propose a structural angle and main refractive indices as two key factors to understand the temperature influence on the divergence angles of the Wollaston prism. The temperature influence on the divergence angles of quartz crystal Wollaston prism is studied theoretically The results show that divergence angles decrease with increasing temperature, while the divergence angle of e-light decrease more quickly than that of o-light. The testing system is established to verify the above results, and the experimental results are in agreement well with the theoretical analysis. (fundamental areas of phenomenology (including applications))

  4. Assessment of PRISM responses to loss of flow events

    International Nuclear Information System (INIS)

    The Nuclear Regulatory Commission (NRC), with Brookhaven National Laboratory providing technical support, is continuing a preapplication review of the 471 MWt, Advanced Liquid Metal Reactor (ALMR), PRISM by General Electric. The revised design has been evaluated using the SSC code, for a series of loss of flow events (LOF) with and without Gas Expansion Modules (GEMs). These devices have a net worth of 69 cents and have reduced the seriousness of the LOF in PRISM. However, it was found that the extremely low probability case of an instantaneous loss of 4 EM pumps without scram could lead to sodium boiling even with the GEMs. (author)

  5. Prism refractive index measurement at INRiM

    International Nuclear Information System (INIS)

    A simple method to measure the refractive index of a glass prism with very low uncertainty was developed at INRiM. The method is a modification of the classical minimum deviation method. A brief description of the methods used to measure the vertex angles of the prism and the angle of minimum deviation is reported together with the uncertainty evaluation. The technique is going to be validated by a comparison between INRiM and two other laboratories. A relative standard uncertainty better than 1 ppm has been obtained

  6. Quartz-Enhanced Photoacoustic Spectroscopy with Right-Angle Prism

    OpenAIRE

    Yongning Liu; Jun Chang; Jie Lian; Zhaojun Liu; Qiang Wang; Zengguang Qin

    2016-01-01

    A right-angle prism was used to enhance the acoustic signal of a quartz-enhanced photoacoustic spectroscopy (QEPAS) system. The incident laser beam was parallelly inverted by the right-angle prism and passed through the gap between two tuning fork prongs again to produce another acoustic excitation. Correspondingly, two pairs of rigid metal tubes were used as acoustic resonators with resonance enhancement factors of 16 and 12, respectively. The QEPAS signal was enhanced by a factor of 22.4 co...

  7. Beam distortion of rotation double prisms with an arbitrary incident angle.

    Science.gov (United States)

    Li, Anhu; Zuo, Qiyou; Sun, Wansong; Yi, Wanli

    2016-07-01

    The distortion of beam shape in rotation Risley prisms is discussed in this paper. Using the ray-tracing method based on vector refraction theorem, a rigorous theoretical model of beam distortion with an arbitrary incident angle is established to explore the influencing factors. For a specified double-prism pair, the emergent beam is squeezed in one direction while stretched in the mutual perpendicular direction, the distortion of which is determined by the relative rotation angle. Moreover, the distortion of beam shape is greatly influenced by the wedge angles and the refractive indices of the prisms, as well as different double-prism configurations, while uncorrelated to the prism thickness and the distance between two prisms. This paper demonstrates the regular change of the beam shape with multiparameter variations in rotation double prisms, which can be applied to the design of rotation double-prism systems. PMID:27409205

  8. Chagas disease and globalization of the Amazon La enfermedad de Chagas y la globalización de la Amazonia

    OpenAIRE

    Roberto Briceño-León

    2007-01-01

    The increasing number of autochthonous cases of Chagas disease in the Amazon since the 1970s has led to fear that the disease may become a new public health problem in the region. This transformation in the disease's epidemiological pattern in the Amazon can be explained by environmental and social changes in the last 30 years. The current article draws on the sociological theory of perverse effects to explain these changes as the unwanted result of the shift from the "inward" development mod...

  9. Cerebellar inactivation impairs memory of learned prism gaze-reach calibrations

    OpenAIRE

    Norris, Scott A.; Hathaway, Emily N.; Taylor, Jordan A.; Thach, W. Thomas

    2011-01-01

    Three monkeys performed a visually guided reach-touch task with and without laterally displacing prisms. The prisms offset the normally aligned gaze/reach and subsequent touch. Naive monkeys showed adaptation, such that on repeated prism trials the gaze-reach angle widened and touches hit nearer the target. On the first subsequent no-prism trial the monkeys exhibited an aftereffect, such that the widened gaze-reach angle persisted and touches missed the target in the direction opposite that o...

  10. A high throughput (>90%), large compensation range, single-prism femtosecond pulse compressor

    OpenAIRE

    Kong, Lingjie; Cui, Meng

    2013-01-01

    We demonstrate a high throughput, large compensation range, single-prism femtosecond pulse compressor, using a single prism and two roof mirrors. The compressor has zero angular dispersion, zero spatial dispersion, zero pulse-front tilt, and unity magnification. The high efficiency is achieved by adopting two roof mirrors as the retroreflectors. We experimentally achieved ~ -14500 fs2 group delay dispersion (GDD) with 30 cm of prism tip-roof mirror prism separation, and ~90.7% system throughp...

  11. Benznidazole Shortage Makes Chagas Disease a Neglected Tropical Disease in Developed Countries: Data from Spain

    Science.gov (United States)

    Navarro, Miriam; Norman, Francesca F.; Pérez-Molina, José Antonio; López-Vélez, Rogelio

    2012-01-01

    Chagas disease is a neglected tropical disease endemic in Latin America. The first-line treatment option is benznidazole, but stocks are expected to run out in the coming months. Spain would need around 5 million benznidazole tablets. This drug shortage could make Chagas disease a neglected tropical disease also in developed countries. PMID:22826485

  12. Simple Method For Testing Of The 90° Angle Of A Reflecting Prism

    Science.gov (United States)

    Ghodgaonkar, A. M.; Tiwari, R. D.; Ramani, K.

    1982-12-01

    A simple method for testing the 90° angle of a reflecting prism by placing two prisms in contact with one another on a standard test plate and counting the number of fringes is outlined. An angle accuracy of less than a second for the angle of a 90° reflecting prism has been obtained.

  13. Simulation of electrically controlled nematic liquid crystal Rochon prism

    Science.gov (United States)

    Buczkowska, M.; Derfel, G.

    2016-09-01

    Operation of an electrically controlled beam steering device based on Rochon prism made by use of nematic liquid crystal is modelled numerically. Deflection angles and angular distribution of light intensity in the deflected beam are calculated. Dynamics of the device is studied. Advantage of application of dual frequency nematic liquid crystal is demonstrated. Role of flexoelectric properties of the nematic is analyzed.

  14. THz Photonic Band-Gap Prisms Fabricated by Fiber Drawing

    DEFF Research Database (Denmark)

    Busch, Stefan F.; Xu, Lipeng; Stecher, Matthias;

    2012-01-01

    We suggest a novel form of polymeric based 3D photonic crystal prisms for THz frequencies which could be fabricated using a standard fiber drawing technique. The structures are modeled and designed using a finite element analyzing technique. Using this simulation software we theoretically study...

  15. Electrowetting-Controlled Dual Liquid Prism for Adaptive Beam Steering

    Science.gov (United States)

    Cheng, Jiangtao

    2015-03-01

    The use of concentrating photovoltaic (CPV) technology has been the most promising method of harvesting solar radiation. These CPV systems often require motor-driven tracking devices to steer the sun's beams onto solar cells. The cost of maintaining these tracking systems is the primary inhibitor for widespread application. We aim to overcome the need for mechanical trackers through the use of an electrowetting-driven solar tracking (EWST) system. The electrowetting-driven solar tracking system consists of an array of novel electrowetting-controlled dual liquid prisms, which are filled with immiscible fluids that have large differences in refractive indices. The naturally formed meniscus between the fluids can function as a dynamic optical prism. Via the full-range modulation of the liquid prisms, incident sunlight can be adaptively tracked, steered, and focused onto CPV cells through a fixed optical condenser. Furthermore, unlike the conventional and cumbersome motor-driven tracking systems used today, the liquid prism system would be suitable for rooftop applications. The results of this project reveal that the EWST system has the potential to generate ~ 70% more green energy at 50% of the conventional capital cost.

  16. The Pacific Oaks College's Prism Principles Professional Development Approach

    Science.gov (United States)

    Beyer, Kalani

    2012-01-01

    In a struggling atmosphere for education, one college is optimistic about the future by offering school districts its PRISM Principles professional development as a means to ensure that "no child is left behind." Pacific Oaks College & Children's School is known for its premiere programs in early childhood education, human…

  17. Portable Remote Imaging Spectrometer (PRISM): Laboratory and Field Calibration

    Science.gov (United States)

    Mouroulis, Pantazis; Van Gorp, Byron; Green, Robert O.; Eastwood, Michael; Boardman, Joseph; Richardson, Brandon S.; Rodriguez, Jose I.; Urquiza, Eugenio; Franklin, Brian D.; Gao, Bo-Cai

    2012-01-01

    We report the characteristics of the Portable Remote Imaging Spectrometer, an airborne sensor specifically designed for the challenges of coastal ocean research. PRISM has high signal to noise ratio and uniformity, as well as low polarization sensitivity. Acquisition of high quality data has been demonstrated with the first engineering flight.

  18. Programmable agile beam steering based on a liquid crystal prism

    International Nuclear Information System (INIS)

    To meet the application need for agile precision beam steering, a novel liquid crystal prism device with a simple structure, convenient control, low cost and applicable performance is presented, and analysed theoretically and experimentally. The relationships between the optical path and the thickness of the liquid crystal cell under different voltages are investigated quantitatively by using a theoretical model. Analysis results show that the optical path profile of the liquid crystal prism has a quasi-linear slope and the standard deviation of the linear slope is less than 16 nm. The slope ratio can be changed by a voltage, which achieves the programmable beam steering and control. Practical liquid crystal prism devices are fabricated. Their deflection angles and wavefront profiles with different voltages are experimentally tested. The results are in good agreement with the simulated results. The results imply that the agile beam steering in a scope of 100 μrad with a micro-rad resolution is substantiated in the device. The two-dimensional beam steering is also achieved by cascading two liquid crystal prism devices. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  19. First Observation of Neutron Deflections by Single Crystal Prisms

    International Nuclear Information System (INIS)

    For a monochromatic neutron beam incident on a single crystal prism, we derived analytic expressions for variations of the deflection δcr and transmitted fraction IO of forward diffracted neutrons, with the incidence angle θ. In the vicinity of a Bragg reflection, δcr deviates sharply from the deflection δam for an equivalent amorphous prism, reaching opposite extrema at either end of the total reflectivity domain and exhibits a 3 orders of magnitude greater sensitivity to θ than δam. We have experimentally observed the variation of δcr and IO across a Bragg reflection for single crystal silicon prisms of various apex angles in several asymmetric Bragg configurations. The observed δcr deviates from δam by upto 27% with sensitivities |dδcr/dθ| upto 0.43 arcsec/arcsec. The results are in harmony with theory. This observation has led to the design of a super-collimator Bragg prism producing neutron beams with sub-arcsecond angular widths.

  20. The demagnetizing field of a non-uniform rectangular prism

    DEFF Research Database (Denmark)

    Smith, Anders; Nielsen, Kaspar Kirstein; Christensen, Dennis;

    2010-01-01

    The effect of demagnetization on the magnetic properties of a rectangular ferromagnetic prism under non-uniform conditions is investigated. A numerical model for solving the spatially varying internal magnetic field is developed, validated and applied to relevant cases. The demagnetizing field......-uniformity of the internal field, especially for non-constant temperature distributions and composite magnetic materials....

  1. A Precision Variable, Double Prism Attenuator for CO(2) Lasers.

    Science.gov (United States)

    Oseki, T; Saito, S

    1971-01-01

    A precision, double prism attenuator for CO(2) lasers, calibrated by its gap capacitance, was constructed to evaluate its possible use as a standard for attenuation measurements. It was found that the accuracy was about 0.1 dB with a dynamic range of about 40 dB.

  2. Study of dose calculation on breast brachytherapy using prism TPS

    Energy Technology Data Exchange (ETDEWEB)

    Fendriani, Yoza; Haryanto, Freddy [Nuclear Physics and Biophysics Research Division, FMIPA Institut Teknologi Bandung, Physics Buildings, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2015-09-30

    PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm{sup 3}. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm{sup 3}. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy.

  3. Sediment compaction and fluid migration in the Makran Accretionary Prism

    Science.gov (United States)

    Minshull, Tim; White, Robert

    1989-06-01

    The Makran continental margin in the Gulf of Oman forms the seaward extremity of an accretionary sediment prism which extends several hundred kilometers inland. A recently acquired multichannel seismic reflection profile shot across the margin imaged the structure of the prism in greater detail than was previously possible and allowed us to investigate the relationship between deformation and pore fluid motion in the region. Velocity analyses of the common midpoint gathers reveal a marked change in velocity structure at the toe of the accretionary wedge, as seen in previous sonobuoy wide-angle data. Accreted sediments show significantly higher vertical velocity gradients than those of sediments entering the prism; this change is interpreted as due to porosity reduction as pore fluids are squeezed out of the compacting sediment. A prominent "bottom simulating reflector" appears 500-800 m beneath the sea bed. Several lines of evidence suggest that this reflector represents the base of a gas hydrate zone underlain by widespread free gas, which may be exsolved from pore water migrating from deep within the sediment pile up permeable fault planes imaged in the profile. The hydrate reflector appears to shallow in the region of some faults, suggesting a temperature anomaly due to the presence of warm pore fluids. A heat flow profile derived from the depth of the hydrate reflector does not show the expected landward decrease as the sediment pile thickens. Simple thermal modeling suggests that advective heat flow within the prism may explain this anomaly. The inferred presence of overpressured pore fluids in the Makran suggests that accreted sediments have a low permeability. The seismic evidence suggests a two-stage compaction process, with rapid initial dewatering through intergranular permeability as sediment enters the prism followed by a buildup of pore pressure as the permeability decreases and fluid migration is restricted to fault zones.

  4. Superconducting magnetic Wollaston prism for neutron spin encoding

    International Nuclear Information System (INIS)

    A magnetic Wollaston prism can spatially split a polarized neutron beam into two beams with different neutron spin states, in a manner analogous to an optical Wollaston prism. Such a Wollaston prism can be used to encode the trajectory of neutrons into the Larmor phase associated with their spin degree of freedom. This encoding can be used for neutron phase-contrast radiography and in spin echo scattering angle measurement (SESAME). In this paper, we show that magnetic Wollaston prisms with highly uniform magnetic fields and low Larmor phase aberration can be constructed to preserve neutron polarization using high temperature superconducting (HTS) materials. The Meissner effect of HTS films is used to confine magnetic fields produced electromagnetically by current-carrying HTS tape wound on suitably shaped soft iron pole pieces. The device is cooled to ∼30 K by a closed cycle refrigerator, eliminating the need to replenish liquid cryogens and greatly simplifying operation and maintenance. A HTS film ensures that the magnetic field transition within the prism is sharp, well-defined, and planar due to the Meissner effect. The spin transport efficiency across the device was measured to be ∼98.5% independent of neutron wavelength and energizing current. The position-dependent Larmor phase of neutron spins was measured at the NIST Center for Neutron Research facility and found to agree well with detailed simulations. The phase varies linearly with horizontal position, as required, and the neutron beam shows little depolarization. Consequently, the device has advantages over existing devices with similar functionality and provides the capability for a large neutron beam (20 mm × 30 mm) and an increase in length scales accessible to SESAME to beyond 10 μm. With further improvements of the external coupling guide field in the prototype device, a larger neutron beam could be employed

  5. Study on the conditions for stabilizing trigonal-prism coordination compounds

    International Nuclear Information System (INIS)

    A new calculating method has been proposed for the elongation and twist of trigonal-prism. The calculations show that the calculated and determined values of the bite for bidentate trigonal prism complexes are similar and that rigidity of the bite favors the stabilization of the trigonal prism configuration. The structural characteristics of the bidentate ligands and central atoms are further discussed based on the structural data of trigonal-prism compounds. The discussion provides a guide for the preparation of new trigonal-prism labelled compounds

  6. Postural Stability Changes during Large Vertical Diplopia Induced by Prism Wear in Normal Subjects

    OpenAIRE

    Matsuo,Toshihiko; Yamasaki,Hanako; Yasuhara,Hirotaka; Hasebe, Kayoko

    2013-01-01

    To test the effect of double vision on postural stability, we measured postural stability by electric stabilometry before prism-wearing and immediately, 15, 30, and 60min after continuous prism-wearing with 6 prism diopters in total (a 3-prism-diopter prism placed with the base up in front of one eye and with the base down in front of the other eye) in 20 normal adult individuals with their eyes open or closed. Changes in stabilometric parameters in the time course of 60min were analyzed stat...

  7. PREDICTION OF OUTCOME OF PAEDIATRIC PATIENTS BY VALIDATING PRISM III SCORING WITHIN 12 HOURS AND PRISM III AT 72-84 HOURS AFTER INITIATION OF THE TREATMENT

    OpenAIRE

    Sonica

    2014-01-01

    `BACKGROUND: One of the scoring systems in Pediatric Intensive Care is the PRISM III (PAEDITRIC RISK OF MORTALITY III) which is an updated version of PRISM. Study was done at time point 72 hrs of initiation of therapy as well in a view that it will better prognosticate the outcome. AIMS: 1. To find out PRISM III within 1st 12 hours of admission and at 72-84 hours of admission, 2. To evaluate any correlation between PRISM III and mortality, 4.To find out correlation between...

  8. Resveratrol Reverses Functional Chagas Heart Disease in Mice

    Science.gov (United States)

    Mata-Santos, Hilton; Vicentino, Amanda R. R.; Feijó, Daniel F.; Meyer-Fernandes, José R.; Paula-Neto, Heitor A.; Medei, Emiliano; Bozza, Marcelo T.; Lannes-Vieira, Joseli; Paiva, Claudia N.

    2016-01-01

    Chronic chagasic cardiomyopathy (CCC) develops years after acute infection by Trypanosoma cruzi and does not improve after trypanocidal therapy, despite reduction of parasite burden. During disease, the heart undergoes oxidative stress, a potential causative factor for arrhythmias and contractile dysfunction. Here we tested whether antioxidants/ cardioprotective drugs could improve cardiac function in established Chagas heart disease. We chose a model that resembles B1-B2 stage of human CCC, treated mice with resveratrol and performed electrocardiography and echocardiography studies. Resveratrol reduced the prolonged PR and QTc intervals, increased heart rates and reversed sinus arrhythmia, atrial and atrioventricular conduction disorders; restored a normal left ventricular ejection fraction, improved stroke volume and cardiac output. Resveratrol activated the AMPK-pathway and reduced both ROS production and heart parasite burden, without interfering with vascularization or myocarditis intensity. Resveratrol was even capable of improving heart function of infected mice when treatment was started late after infection, while trypanocidal drug benznidazole failed. We attempted to mimic resveratrol’s actions using metformin (AMPK-activator) or tempol (SOD-mimetic). Metformin and tempol mimicked the beneficial effects of resveratrol on heart function and decreased lipid peroxidation, but did not alter parasite burden. These results indicate that AMPK activation and ROS neutralization are key strategies to induce tolerance to Chagas heart disease. Despite all tissue damage observed in established Chagas heart disease, we found that a physiological dysfunction can still be reversed by treatment with resveratrol, metformin and tempol, resulting in improved heart function and representing a starting point to develop innovative therapies in CCC. PMID:27788262

  9. Enfermedad de Chagas-Mazza congenita en Salta

    OpenAIRE

    Contreras Silvia; Fernandez María Rosa; Agüero Fernando; Desse Desse Javier; Orduna Tomás; Martino Olindo

    1999-01-01

    Se estudió la infección por T. cruzi en mujeres embarazadas en la localidad de General Güemes, provincia de Salta. La misma fue del 12,3 %. El 8,8% de los recién nacidos estudiados tuvieron diagnóstico de Enfermedad de Chagas utilizando la técnica directa (microhematocrito). Todos fueron tratados con benznidazol a razón de 5mg/kg/día durante 30 dias. Todos presentaron anemia, que fue interpretada como reacción adversa medicamentosa. Se estima que la técnica directa representa la mejor opción ...

  10. Risks of endemicity, morbidity and perspectives regarding the control of Chagas disease in the Amazon Region

    Directory of Open Access Journals (Sweden)

    José Rodrigues Coura

    2012-03-01

    Full Text Available Chagas disease, in the Amazon Region as elsewhere, can be considered an enzootic disease of wild animals or an anthropozoonosis, an accidental disease of humans that is acquired when humans penetrate a wild ecosystem or when wild triatomines invade human dwellings attracted by light or searching for human blood. The risk of endemic Chagas disease in the Amazon Region is associated with the following phenomena: (i extensive deforestation associated with the displacement of wild mammals, which are the normal sources of blood for triatomines, (ii adaptation of wild triatomines to human dwellings due to the need for a new source of blood for feeding and (iii uncontrolled migration of human populations and domestic animals that are already infected with Trypanosoma cruzi from areas endemic for Chagas disease to the Amazon Region. Several outbreaks of severe acute cases of Chagas disease, as well as chronic cases, have been described in the Amazon Region. Control measures targeted to avoiding endemic Chagas disease in the Amazon Region should be the following: improving health education in communities, training public health officials and communities for vector and Chagas disease surveillance and training local physicians to recognise and treat acute and chronic cases of Chagas diseases as soon as possible.

  11. Risks of endemicity, morbidity and perspectives regarding the control of Chagas disease in the Amazon Region.

    Science.gov (United States)

    Coura, José Rodrigues; Junqueira, Angela Cv

    2012-03-01

    Chagas disease, in the Amazon Region as elsewhere, can be considered an enzootic disease of wild animals or an anthropozoonosis, an accidental disease of humans that is acquired when humans penetrate a wild ecosystem or when wild triatomines invade human dwellings attracted by light or searching for human blood. The risk of endemic Chagas disease in the Amazon Region is associated with the following phenomena: (i) extensive deforestation associated with the displacement of wild mammals, which are the normal sources of blood for triatomines, (ii) adaptation of wild triatomines to human dwellings due to the need for a new source of blood for feeding and (iii) uncontrolled migration of human populations and domestic animals that are already infected with Trypanosoma cruzi from areas endemic for Chagas disease to the Amazon Region. Several outbreaks of severe acute cases of Chagas disease, as well as chronic cases, have been described in the Amazon Region. Control measures targeted to avoiding endemic Chagas disease in the Amazon Region should be the following: improving health education in communities, training public health officials and communities for vector and Chagas disease surveillance and training local physicians to recognise and treat acute and chronic cases of Chagas diseases as soon as possible.

  12. When a misperception favors a tragedy: Carlos Chagas and the Nobel Prize of 1921.

    Science.gov (United States)

    Bestetti, Reinaldo B; Couto, Lucélio B; Cardinalli-Neto, Augusto

    2013-11-20

    Carlos Chagas, the discoverer of Chagas' disease was nominated to the Nobel Prize in 1921, but none did win the prize in that year. As a leader of a young scientist team, he discovered all aspects of the new disease from 1909 to 1920. It is still obscure why he did not win the Nobel Prize in 1921. Chagas was discarded by Gunnar Hedrèn on April 16, 1921. Hedrèn should have made a written report about the details of his evaluation to the Nobel Committee. However, such a document has not been found in the Nobel Committee Archives. No evidence of detractions made by Brazilian scientists on Chagas was found. Since Chagas nomination was consistent with the Nobel Committee requirements, as seen in the presentation letter by until now unknown Cypriano de Freitas, it become clear that Chagas did not win the Nobel Prize exclusively because the Nobel Committee did not perceive the importance of his discovery. Thus, it would be fair a posthumous Nobel Prize of 1921 to Carlos Chagas. A diploma of the Nobel Prize, as precedent with Dogmack in 1947, would recognize the merit of the scientist who made the most complete medical discovery of all times.

  13. Intricacies of Feedback in Computer-based Prism Adaptation Therapy

    DEFF Research Database (Denmark)

    Wilms, Inge Linda; Rytter, Hana Malá

    whether the PAT method can be executed with similar effect using a computer with a touch screen.   62 healthy subjects were subjected to two experimental conditions: 1) pointing out at targets using the original box, 2) pointing out at targets on a computer attached touch screen. In both conditions...... on the touch screen (indirect feedback), 2) the feedback was provided by seeing one's own pointing finger, with no graphical feedback on the computer screen (direct feedback).   The results show that it is possible to obtain similar aftereffects from PAT by using a computer method but only when providing......Prism Adaptation Therapy (PAT) is an intervention method for treatment of attentional disorders, such as neglect e.g. 1,2. The method involves repeated pointing at specified targets with or without prism glasses using a specifically designed wooden box. The aim of this study was to ascertain...

  14. Hyperbolic prisms and foams in Hele-Shaw cells

    International Nuclear Information System (INIS)

    The propagation of light in foams creates patterns which are generated due to the reflection and refraction of light. One of these patterns is observed by the formation of multiple mirror images inside liquid bridges in a layer of bubbles in a Hele-Shaw cell. We are presenting the existence of these patterns in foams and their relation with hyperbolic geometry and Sierpinski gaskets using the Poincare disk model. The images obtained from the experiment in foams are compared to the case of hyperbolic optical elements. -- Highlights: → The chaotic scattering of light in foams generating deltoid patterns is based on hyperbolic geometry. → The deltoid patterns are obtained through the Plateau borders in a Hele-Shaw cell. → The Plateau borders act like hyperbolic prism. → Some effects of the refraction and reflection of the light rays were studied using a hyperbolic prism.

  15. Standard Practice for Inspection of Transparent Parts by Prism

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 Aerospace transparencies undergo high stresses induced by flight, environmental, or other factors. The transparency attachment points are especially subject to fatigue. These areas of fatigue are often obstructed or hidden from normal inspection. An inspector, following the techniques described in this practice, shall use a prism to view damage located near transparency bolt holes, voids, and delamination that are hidden by edge strips or frames. 1.2 The purpose of this practice is to provide acceptable methods for performing prism inspections of transparent materials with specific emphasis on aircraft windscreens and canopies. Caveats and lessons learned from experience are included to assist authors in writing tailored inspection instructions for specific applications. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicab...

  16. Stereovision Imaging in Smart Mobile Phone Using Add on Prisms

    Science.gov (United States)

    Bar-Magen Numhauser, Jonathan; Zalevsky, Zeev

    2014-03-01

    In this work we present the use of a prism-based add on component installed on top of a smart phone to achieve stereovision capabilities using iPhone mobile operating system. Through these components and the combination of the appropriate application programming interface and mathematical algorithms the obtained results will permit the analysis of possible enhancements for new uses to such system, in a variety of areas including medicine and communications.

  17. Prism-coupled light emission from tunnel junctions

    Science.gov (United States)

    Ushioda, S.; Rutledge, J. E.; Pierce, R. M.

    1985-01-01

    Completely p-polarized light emission has been observed from smooth Al-AlO(x)-Au tunnel junctions placed on a prism coupler. The angle and polarization dependence demonstrate unambiguously that the emitted light is radiated by the fast-mode surface plasmon polariton. The emission spectra suggest that the dominant process for the excitation of the fast mode is through conversion of the slow mode to the fast mode mediated by residual roughness on the junction surface.

  18. Advanced SFR Concept Based on PRISM and KALIMER

    International Nuclear Information System (INIS)

    The Sodium-cooled Fast Reactor has been recognized as one of the promising nuclear options for generating electricity with efficient uranium resource utilization and reduction of radioactive wastes from nuclear power plants. This paper compares design features, identifies differences between KALIMER-600 and S-PRISM sodium-cooled reactors, and derives R and D requirements in order to explore the possibility of developing a novel SFR concept. (author)

  19. Prism adaptation does not alter configural processing of faces

    OpenAIRE

    Bultitude, Janet H.; Downing, Paul E.; Robert D. Rafal

    2013-01-01

    Patients with hemispatial neglect (‘neglect’) following a brain lesion show difficulty responding or orienting to objects and events on the left side of space. Substantial evidence supports the use of a sensorimotor training technique called prism adaptation as a treatment for neglect. Reaching for visual targets viewed through prismatic lenses that induce a rightward shift in the visual image results in a leftward recalibration of reaching movements that is accompanied by a reduction of symp...

  20. Prism therapy and visual rehabilitation in homonymous visual field loss.

    LENUS (Irish Health Repository)

    O'Neill, Evelyn C

    2011-02-01

    Homonymous visual field defects (HVFD) are common and frequently occur after cerebrovascular accidents. They significantly impair visual function and cause disability particularly with regard to visual exploration. The purpose of this study was to assess a novel interventional treatment of monocular prism therapy on visual functioning in patients with HVFD of varied etiology using vision targeted, health-related quality of life (QOL) questionnaires. Our secondary aim was to confirm monocular and binocular visual field expansion pre- and posttreatment.

  1. Prism therapy and visual rehabilitation in homonymous visual field loss.

    LENUS (Irish Health Repository)

    O'Neill, Evelyn C

    2012-02-01

    PURPOSE: Homonymous visual field defects (HVFD) are common and frequently occur after cerebrovascular accidents. They significantly impair visual function and cause disability particularly with regard to visual exploration. The purpose of this study was to assess a novel interventional treatment of monocular prism therapy on visual functioning in patients with HVFD of varied etiology using vision targeted, health-related quality of life (QOL) questionnaires. Our secondary aim was to confirm monocular and binocular visual field expansion pre- and posttreatment. METHODS: Twelve patients with acquired, documented HVFD were eligible to be included. All patients underwent specific vision-targeted, health-related QOL questionnaire and monocular and binocular Goldmann perimetry before commencing prism therapy. Patients were fitted with monocular prisms on the side of the HVFD with the base-in the direction of the field defect creating a peripheral optical exotropia and field expansion. After the treatment period, QOL questionnaires and perimetry were repeated. RESULTS: Twelve patients were included in the treatment group, 10 of whom were included in data analysis. Overall, there was significant improvement within multiple vision-related, QOL functioning parameters, specifically within the domains of general health (p < 0.01), general vision (p < 0.05), distance vision (p < 0.01), peripheral vision (p < 0.05), role difficulties (p < 0.05), dependency (p < 0.05), and social functioning (p < 0.05). Visual field expansion was shown when measured monocularly and binocularly during the study period in comparison with pretreatment baselines. CONCLUSIONS: Patients with HVFD demonstrate decreased QOL. Monocular sector prisms can improve the QOL and expand the visual field in these patients.

  2. A multi-species bait for Chagas disease vectors.

    Directory of Open Access Journals (Sweden)

    Theo Mota

    2014-02-01

    Full Text Available BACKGROUND: Triatomine bugs are the insect vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. These insects are known to aggregate inside shelters during daylight hours and it has been demonstrated that within shelters, the aggregation is induced by volatiles emitted from bug feces. These signals promote inter-species aggregation among most species studied, but the chemical composition is unknown. METHODOLOGY/PRINCIPAL FINDINGS: In the present work, feces from larvae of the three species were obtained and volatile compounds were identified by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS. We identified five compounds, all present in feces of all of the three species: Triatoma infestans, Panstrongylus megistus and Triatoma brasiliensis. These substances were tested for attractivity and ability to recruit insects into shelters. Behaviorally active doses of the five substances were obtained for all three triatomine species. The bugs were significantly attracted to shelters baited with blends of 160 ng or 1.6 µg of each substance. CONCLUSIONS/SIGNIFICANCE: Common compounds were found in the feces of vectors of Chagas disease that actively recruited insects into shelters, which suggests that this blend of compounds could be used for the development of baits for early detection of reinfestation with triatomine bugs.

  3. Melatonin in Chagas´ disease: Possible therapeutic value

    Directory of Open Access Journals (Sweden)

    Daniel P. Cardinali

    2011-10-01

    Full Text Available Chagas' disease is a severe health problem in Latin America, causing approximately 50 000 deaths a year, with approximately 18 million infected people. About 25-30% of the patients infected with Trypanosoma cruzi develop the chronic form of the disease. The protective response against T. cruzi depends on both innate and acquired immunity involving macrophages, natural killer cells, T and B lymphocytes, and the production of proinflammatory Th-1 cytokines. In addition, an increased nitric oxide (NO production in macrophages leading to effective microbicidal action is needed to control parasitemia. Melatonin is detectable in T. cruzi and may play a role in promoting infection whereas, when administered in high doses during the acute phase of T. cruzi infection, it can decrease parasitemia while reducing NO production. During chronic disease progression, the sustained oxidative stress concomitant to myocardial damage could be reduced by administering melatonin. It is hypothesized that the coordinated administration of a melatonin agonist like the MT1/MT2 agonist ramelteon, that lacks antioxidant activity and may not affect NO production during the acute phase, and of melatonin in doses high enough to decrease oxidative damage, to preserve mitochondrial and to prevent cardiomyopathy during the chronic phase, could be a novel add-on treatment of Chagas´ disease.

  4. Chagas Disease in Dogs from Endemic Areas of Costa Rica

    Directory of Open Access Journals (Sweden)

    Montenegro Victor M

    2002-01-01

    Full Text Available Dogs with the presumptive diagnosis of Chagas disease are commonly sent to our School of Veterinary Medicine by independent veterinarians. This prompted us to evaluate the prevalence of canine trypanosomiasis in some villages of the Central Valley of Costa Rica. A total of 54 dogs (21 males and 33 females from five rural villages, with ages between 3 months and 10 years old, were bled and submitted to three serological tests: indirect immunofluorescence, indirect hemagglutination and ELISA. Among all animals, 15 (27.7% revealed antibodies (6 pure bred and 9 mongrels and in 3 of them the parasite was also demonstrated by xenodiagnosis. All positive animals except 1, and 9 negative animals (control group were examined by X-rays and electrocardiography, revealing different degrees of cardiomegaly and ECG alteration, consistent with Chagas disease pathology in one dog (SA-11 of the infected ones. Examination of 50 inhabitants living in the houses where dogs and Triatoma dimidiata were found, yielded negative serological reactions. This was assumed to support the hypothesis that dogs are commonly infected by the oral route, a more effective means of infection compared with the vector transmission mechanism that occurs in humans.

  5. Urban transmission of Chagas disease in Cochabamba, Bolivia

    Directory of Open Access Journals (Sweden)

    N Medrano-Mercado

    2008-08-01

    Full Text Available Chagas disease is a major public health problem in Bolivia. In the city of Cochabamba, 58% of the population lives in peripheral urban districts ("popular zones" where the infection prevalence is extremely high. From 1995 to 1999, we studied the demographics of Chagas infections in children from five to 13 years old (n = 2218 from the South zone (SZ and North zone (NZ districts, which differ in social, environmental, and agricultural conditions. Information gathered from these districts demonstrates qualitative and quantitative evidence for the active transmission of Trypanosoma cruzi in urban Cochabamba. Seropositivity was high in both zones (25% in SZ and 19% in NZ. We observed a high risk of infection in children from five to nine years old in SZ, but in NZ, a higher risk occurred in children aged 10-13, with odds ratio for infection three times higher in NZ than in SZ. This difference was not due to triatomine density, since more than 1,000 Triatoma infestans were captured in both zones, but was possibly secondary to the vector infection rate (79% in SZ and 37% in NZ. Electrocardiogram abnormalities were found to be prevalent in children and pre-adolescents (SZ = 40%, NZ = 17%, indicating that under continuous exposure to infection and re-infection, a severe form of the disease may develop early in life. This work demonstrates that T. cruzi infection should also be considered an urban health problem and is not restricted to the rural areas and small villages of Bolivia.

  6. Chagas y SIDA, la importancia del diagnóstico precoz

    OpenAIRE

    Sergio R. Auger; Rubén Storino; Miguel De Rosa; Oscar Caravello; González, María I.; Edgardo Botaro; Liliana Bonelli; Oscar Rossini

    2005-01-01

    Objetivos: Evaluar las vías de contagio, la reactivación y la evolución de la enfermedad de Chagas en pacientes con HIV. Material y métodos Se incorporaron pacientes internados con SIDA y Chagas reactivo. Se evaluaron la epidemiología, la adicción a drogas, la reactivación de la enfermedad de Chagas y el órgano blanco más afectado, la demora del inicio de tratamiento antiparasitario y la evolución posterior. Se realizaron serologías, estudios parasitológicos en sangre y líquido cefalorraq...

  7. Stabilization of a self-referenced, prism-based, Cr:forsterite laser frequency comb using an intracavity prism

    International Nuclear Information System (INIS)

    The frequency comb from a prism-based Cr:forsterite laser has been frequency stabilized using intracavity prism insertion and pump power modulation. Absolute frequency measurements of a CW fiber laser stabilized to the P(13) transition of acetylene demonstrate a fractional instability of ∼2x10-11 at a 1 s gate time, limited by a commercial Global Positioning System (GPS)-disciplined rubidium oscillator. Additionally, absolute frequency measurements made simultaneously using a second frequency comb indicate relative instabilities of 3x10-12 for both combs for a 1 s gate time. Estimations of the carrier-envelope offset frequency linewidth based on relative intensity noise and the response dynamics of the carrier-envelope offset to pump power changes confirm the observed linewidths.

  8. Local Seismicity Recorded by ChilePEPPER: Implications for Dynamic Accretionary Prism Response and Long-term Prism Evolution

    Science.gov (United States)

    de Moor, A.; Trehu, A. M.; Tryon, M. D.

    2015-12-01

    To investigate the dynamic response of the outer accretionary wedge updip from the patch of greatest slip during the Mw8.8 2010 Maule earthquake, 10 Ocean Bottom Seismometers (OBS) were deployed from May 2012 to March 2013 in a small array with an inter-instrument spacing of ~12 km . Nine instruments were recovered, with 4 recording data on 3 intermediate-band 3-component seismometers and a differential pressure gauge and 5 recording data from absolute pressure gauges. [note: All instruments were also equipped with a fluid flow meter sensitive to flow rates as low as 0.0001 cm/yr in or out of the sediments. However, no flow signal was detected.] Here we present hypocenters for 569 local events that have S-P times less than 17 seconds (i.e. within ~125 km of the array) using hand-picked arrival times and a 1D velocity model derived from a 2D seismic refraction profile through the region (Moscoso et al 2011, EPSL). We analyze the distribution of seismicity in the context of published slip models, ChilePEPPER high-resolution seismic reflection data, critical taper analysis done by Cubas et al 2013 (EPSL), and offshore gravity data. The data show distinct segmentation within the outer prism. The northern section of the study area is characterized by a lack of seismicity, accretion of nearly all incoming sediment and a prism at critical taper. In contrast, abundant seismicity, significant sediment underthrusting at the deformation front and a prism below critical taper angle characterize the southern part of the study area. Both coseismic slip and post-rupture local seismicity can be related to density anomalies within the upper plate as revealed by free air gravity data corrected for the effects of bathymetry and the subducting plate. [ChilePEPPER - Project Evaluating Prism Post-Earthquake Response

  9. Prism: a new approach to radiotherapy planning software

    International Nuclear Information System (INIS)

    Purpose: We describe the capabilities and performance of Prism, an innovative new radiotherapy planning system with unusual features and design. The design and implementation strategies are intended to assure high quality and clinical acceptability. The features include Artificial Intelligence tools and special support for multileaf collimator (MLC) systems. The design provides unusual flexibility of operation and ease of expansion. Methods and Materials: We have implemented Prism, a three-dimensional (3D) radiotherapy treatment-planning system on standard commercial workstations with the widely available X window system. The design and implementation use ideas taken from recent software engineering research, for example, the use of behavioral entity-relationship modeling and the 'Mediator Method' instead of ad-hoc programming. The Prism system includes the usual features of a 3D planning system, including Beam's Eye View and the ability to simulate any treatment geometry possible with any standard radiotherapy accelerator. It includes a rule-based expert system for automated generation of the planning target volume as defined in ICRU Report 50. In addition, it provides special support for planning treatments with a multileaf collimator (MLC). We also implemented a Radiotherapy Treatment Planning Tools Foundation for Prism, so that we are able to use software tools from other institutions without any source code modification. Results: The Prism system has been in clinical operation at the University of Washington since July 1994 and has been installed at several other clinics. The system is run simultaneously by several users, each with their own workstation operating from a common networked database and software. In addition to the dosimetrists, the system is used by radiation oncologists to define tumor and target volumes and by radiation therapists to select treatment setups to load into a computer controlled accelerator. Conclusions: Experience with the

  10. IL18 Gene Variants Influence the Susceptibility to Chagas Disease.

    Science.gov (United States)

    Leon Rodriguez, Daniel A; Carmona, F David; Echeverría, Luis Eduardo; González, Clara Isabel; Martin, Javier

    2016-03-01

    Chagas disease is a parasitic disorder caused by the infection with the flagellated protozoan Trypanosoma cruzi. According to the World Health Organization, more than six million people are currently infected in endemic regions. Genetic factors have been proposed to influence predisposition to infection and development of severe clinical phenotypes like chronic Chagas cardiomyopathy (CCC). Interleukin 18 (IL18) encodes a proinflammatory cytokine that has been proposed to be involved in controlling T. cruzi infection. In this study, we analyzed the possible role of six IL18 gene variants (rs5744258, rs360722, rs2043055, rs187238, rs1946518 and rs360719), which cover most of the variation within the locus, in the susceptibility to infection by T. cruzi and/or CCC. In total, 1,171 individuals from a Colombian region endemic for Chagas disease, classified as seronegative (n = 595), seropositive asymptomatic (n = 175) and CCC (n = 401), were genotyped using TaqMan probes. Significant associations with T. cruzi infection were observed when comparing seronegative and seropositive individuals for rs187238 (P = 2.18E-03, OR = 0.77), rs360719 (P = 1.49E-03, OR = 0.76), rs2043055 (P = 2.52E-03, OR = 1.29), and rs1946518 (P = 0.0162, OR = 1.22). However, dependence analyses suggested that the association was mainly driven by the polymorphism rs360719. This variant is located within the promoter region of the IL18 gene, and it has been described that it creates a binding site for the transcription factor OCT-1 affecting IL-18 expression levels. In addition, no evidence of association was observed between any of the analyzed IL18 gene polymorphisms and the development of CCC. In summary, our data suggest that genetic variation within the promoter region of IL18 is directly involved in the susceptibility to infection by T. cruzi, which provides novel insight into disease pathophysiology and adds new perspectives to achieve a more effective disease control. PMID:27027876

  11. On palms, bugs, and Chagas disease in the Americas.

    Science.gov (United States)

    Abad-Franch, Fernando; Lima, Marli M; Sarquis, Otília; Gurgel-Gonçalves, Rodrigo; Sánchez-Martín, María; Calzada, José; Saldaña, Azael; Monteiro, Fernando A; Palomeque, Francisco S; Santos, Walter S; Angulo, Victor M; Esteban, Lyda; Dias, Fernando B S; Diotaiuti, Liléia; Bar, María Esther; Gottdenker, Nicole L

    2015-11-01

    Palms are ubiquitous across Neotropical landscapes, from pristine forests or savannahs to large cities. Although palms provide useful ecosystem services, they also offer suitable habitat for triatomines and for Trypanosoma cruzi mammalian hosts. Wild triatomines often invade houses by flying from nearby palms, potentially leading to new cases of human Chagas disease. Understanding and predicting triatomine-palm associations and palm infestation probabilities is important for enhancing Chagas disease prevention in areas where palm-associated vectors transmit T. cruzi. We present a comprehensive overview of palm infestation by triatomines in the Americas, combining a thorough reanalysis of our published and unpublished records with an in-depth review of the literature. We use site-occupancy modeling (SOM) to examine infestation in 3590 palms sampled with non-destructive methods, and standard statistics to describe and compare infestation in 2940 palms sampled by felling-and-dissection. Thirty-eight palm species (18 genera) have been reported to be infested by ∼39 triatomine species (10 genera) from the USA to Argentina. Overall infestation varied from 49.1-55.3% (SOM) to 62.6-66.1% (dissection), with important heterogeneities among sub-regions and particularly among palm species. Large palms with complex crowns (e.g., Attalea butyracea, Acrocomia aculeata) and some medium-crowned palms (e.g., Copernicia, Butia) are often infested; in slender, small-crowned palms (e.g., Euterpe) triatomines associate with vertebrate nests. Palm infestation tends to be higher in rural settings, but urban palms can also be infested. Most Rhodnius species are probably true palm specialists, whereas Psammolestes, Eratyrus, Cavernicola, Panstrongylus, Triatoma, Alberprosenia, and some Bolboderini seem to use palms opportunistically. Palms provide extensive habitat for enzootic T. cruzi cycles and a critical link between wild cycles and transmission to humans. Unless effective means to

  12. Quinoxaline 1,4-di-N-oxide Derivatives: Interest in the Treatment of Chagas Disease [ Derivados 1,4- i-N-óxido Quinoxalinas: O Interesse no Tratamento da Doença de Chagas

    OpenAIRE

    Elsa Moreno - Viguri; Silvia Pérez-Silanes

    2013-01-01

    More than 100 million people are at risk of contracting Chagas disease. It is estimated that in 2008, Chagas disease was responsible for the death of more than 10,000 people. Despite the fact that there are more than 100 years since the disease was discove red, safe and effective treatments still have to be found. Therefore, new drugs active against Chagas disease are urgently required. Quinoxaline derivatives show very interesting biological properties (anti-infective, cytotoxic, anticandida...

  13. Mapping of Chagas disease research: analysis of publications in the period between 1940 and 2009

    Directory of Open Access Journals (Sweden)

    José Manuel Ramos

    2011-12-01

    Full Text Available INTRODUCTION: Publications are often used as a measure of success in research work. Chagas disease occurs in Central and Southern America. However, during the past years, the disease has been occurring outside Latin America due to migration from endemic zones. This article describes a bibliometric review of the literature on Chagas disease research indexed in PubMed during a 70-year period. METHODS: Medline was used via the PubMed online service of the U.S. National Library of Medicine from 1940 to 2009. The search strategy was: Chagas disease [MeSH] OR Trypanosoma cruzi [MeSH]. RESULTS: A total of 13,989 references were retrieved. The number of publications increased steadily over time from 1,361 (1940-1969 to 5,430 (2000-2009 (coefficient of determination for linear fit, R²=0.910. Eight journals contained 25% of the Chagas disease literature. Of the publications, 64.2% came from endemic countries. Brazil was the predominant country (37%, followed by the United States (17.6% and Argentina (14%. The ranking in production changed when the number of publications was normalized by estimated cases of Chagas disease (Panama and Uruguay, population (Argentina and Uruguay, and gross domestic product (Bolivia and Brazil. CONCLUSIONS: Several Latin American countries, where the prevalence of T. cruzi infection was not very high, were the main producers of the Chagas disease literature, after adjusting for economic and population indexes. The countries with more estimated cases of Chagas disease produced less research on Chagas disease than some developed countries.

  14. Aortic distensibility measured by pulse-wave velocity is not modified in patients with Chagas' disease

    Directory of Open Access Journals (Sweden)

    Arteaga Edmundo

    2006-06-01

    Full Text Available Abstract Background Experimental studies demonstrate that infection with trypanosoma cruzi causes vasculitis. The inflammatory lesion process could hypothetically lead to decreased distensibility of large and small arteries in advanced Chagas' disease. We tested this hypothesis. Methods and results We evaluated carotid-femoral pulse-wave velocity (PWV in 53 Chagas' disease patients compared with 31 healthy volunteers (control group. The 53 patients were classified into 3 groups: 1 16 with indeterminate form of Chagas' disease; 2 18 with Chagas' disease, electrocardiographic abnormalities, and normal systolic function; 3 19 with Chagas' disease, systolic dysfunction, and mild-to-moderate congestive heart failure. No difference was noted between the 4 groups regarding carotid-femoral PWV (8.4 ± 1.1 vs 8.2 ± 1.5 vs 8.2 ± 1.4 vs 8.7 ± 1.6 m/s, P = 0.6 or pulse pressure (39.5 ± 7.6 vs 39.3 ± 8.1 vs 39.5 ± 7.4 vs 39.7 ± 6.9 mm Hg, P = 0.9. A positive, significant, similar correlation occurred between PWV and age in patients with Chagas' disease (r = 0.42, P = 0.002, in controls (r = 0.48, P = 0.006, and also between PWV and systolic blood pressure in both groups (patients with Chagas' disease, r = 0.38, P = 0.005; healthy subjects, r = 0.36, P = 0.043. Conclusion Carotid femoral pulse-wave velocity is not modified in patients with Chagas' disease, suggesting that elastic properties of large arteries are not affected in this disorder.

  15. Inflammation Enhances the Risks of Stroke and Death in Chronic Chagas Disease Patients

    OpenAIRE

    Guedes, Paulo Marcos Matta; de Andrade, Cléber Mesquita; Nunes, Daniela Ferreira; de Sena Pereira, Nathalie; Queiroga, Tamyres Bernadete Dantas; Machado-Coelho, George Luiz Lins; Nascimento, Manuela Sales Lima; Do-Valle-Matta, Maria Adelaide; da Câmara, Antônia Cláudia Jácome; Chiari, Egler; Galvão, Lúcia Maria da Cunha

    2016-01-01

    Ischemic strokes have been implicated as a cause of death in Chagas disease patients. Inflammation has been recognized as a key component in all ischemic processes, including the intravascular events triggered by vessel interruption, brain damage and repair. In this study, we evaluated the association between inflammatory markers and the death risk (DR) and stroke risk (SR) of patients with different clinical forms of chronic Chagas disease. The mRNA expression levels of cytokines, transcript...

  16. The potential for emergence of Chagas disease in the United States

    Directory of Open Access Journals (Sweden)

    Rebecca Click Lambert

    2008-05-01

    Full Text Available To determine the risk for Chagas disease (American trypanosomiasis in the United States, the characteristics that make the triatomine vector effective and the areas most at risk for transmission were delineated. In addition, the status of Chagas disease awareness among physicians in areas with a potential risk for the disease was determined. A geographical information system (GIS was used to analyze three triatomine species within the United States known to harbor Trypanosoma cruzi and that exhibit qualities of domesticity. An analysis of the minimum temperature threshold for increased triatomine activity delineates the current population at increased risk, and by incorporating temperature predictions for 2030, the population at risk under a future climate scenario was also delineated. Considering both environmental and social factors, a vignette-based physician survey, based on the results of the GIS analysis, was used to gauge the level of awareness of Chagas disease within the delineated higher risk range. The current area at increased risk for Chagas disease includes much of the southern United States, and the higher risk range is expected to expand into the central United States based upon the 1°C (1.8°F increase in temperature predicted by the Intergovernmental Panel on Climate Change (IPCC by the year 2030. Survey results indicate a limited consideration of Chagas disease during differential diagnosis, illustrating that the low number of Chagas disease cases discovered in the United States may be attributable to a lack of disease awareness as opposed to a lack of disease threat. This study combines GIS and survey analyses to evaluate the role that temperature variability and disease awareness among physicians play in the potential emergence of Chagas disease in the United States. This approach indicates that there is a potential for Chagas disease to emerge in the United States.

  17. Prism adaptation magnitude has differential influences on perceptual versus manual responses.

    Science.gov (United States)

    Striemer, Christopher L; Russell, Karyn; Nath, Priya

    2016-10-01

    Previous research has indicated that rightward prism adaptation can reduce symptoms of spatial neglect following right brain damage. In addition, leftward prism adaptation can create "neglect-like" patterns of performance in healthy adults on tasks that measure attention and spatial biases. Although a great deal of research has focused on which behaviors are influenced by prism adaptation, very few studies have focused directly on how the magnitude of visual shift induced by prisms might be related to the observed aftereffects, or the effects of prisms on measures of attentional and spatial biases. In the current study, we examined these questions by having groups of healthy adult participants complete manual line bisection and landmark tasks prior to and following adaptation to either 8.5° (15 diopter; n = 22) or 17° (30 diopter; n = 25) leftward shifting prisms. Our results demonstrated a significantly larger rightward shift in straight-ahead pointing (a measure of prism aftereffect) following adaptation to 17°, compared to 8.5° leftward shifting prisms. In addition, only 17° leftward shifting prisms resulted in a significant rightward shift in line bisection following adaptation. However, there was a significant change in performance on the landmark task pre- versus post-adaptation in both the 8.5° and 17° leftward shifting prism groups. Interestingly, correlation analyses indicated that changes in straight-ahead pointing pre- versus post-adaptation were positively correlated with changes in performance on the manual line bisection task, but not the landmark task. These data suggest that larger magnitudes of prism adaptation seem to have a greater influence on tasks that require a response with the adapted hand (i.e., line bisection), compared to tasks that only require a perceptual judgment (i.e., the landmark task). In addition, these data provide further evidence that the effects of prisms on manual and perceptual responses are not related to one

  18. DYNAMIQUE DES PRISMES OROGÉNIQUES, LE RÔLE DES FLUIDES

    OpenAIRE

    Deville, Eric

    2011-01-01

    The work presented is a dossier presented to anobyainaccreditation to supervise research (HDR). It concerns the role of fluids in orogenic prisms. The presentation is organized around three approaches: (1) an integrated approach to iconic sites: a mature accretionary prism (the prism of Barbados) and a chain collision (Western Alps), (2) a methodological approach, and (3) a thematic approach to study processes poorly understood and to discuss problems of structure and dynamics of convergent o...

  19. Experimental study on the flow regimes past a confined prism undergoing self-sustained oscillations

    International Nuclear Information System (INIS)

    Highlights: • A experimental study is presented on the flow regimes past a confined prism. • Flow is 3D and involves the self-sustained motion of the prism. • Different regimes are indentified as a function of two control parameters. • Control parameters are the Reynolds number and the density ratio. • The concept has potential industrial applications. - Abstract: An experimental study based on Particle Image Velocimetry (PIV) is presented with the objective of studying the flow regimes that appear in the flow past a confined prism undergoing self-sustained oscillations at low Reynolds numbers (Re). The square-section prism, placed inside a 3D square cross-section vertical channel with a confinement ratio of 1/2.5, was tethered to the channel walls and, therefore, it was allowed to move freely transverse to the incoming flow. Re (based on the prism cross-section height) was varied in the range from 100 to 700. Three different prism to fluid density ratios (m∗) were considered: 0.56, 0.70, and 0.91. These two parameters, Re and m∗, were used to map the results obtained. In particular, it was found that five different regimes appear: (1) steady prism with steady recirculation bubble, (2) steady prism with unsteady vortex shedding wake, (3) large amplitude low frequency oscillating prism with unsteady vortex shedding wake, (4) small amplitude high frequency oscillating prism with unsteady vortex shedding wake, and (5) irregular/chaotic motion of both the prism and the wake. The PIV results and associated numerical simulations were used to analyze the different prism and wake states

  20. Redshift estimation from low-resolution prism SEDs with an NGST MOS

    OpenAIRE

    Teplitz, Harry I.; Malumuth, Eliot; Woodgate, Bruce E.; Moseley, S. Harvey; Gardner, Jonathan P.; Kimble, Randy A.; Bowers, Charles W.; Kutyrev, Alexander S.; Fettig, Rainer K.; Wesenberg, Richard P.; Mentzell, John E.

    2000-01-01

    We discuss the utility of a low resolution prism as a component of a Multi-Object Spectrometer for NASA's proposed Next Generation Space Telescope (NGST). Low resolution prism spectroscopy permits simultaneous observation of the 0.6-5micron wavelength regime at R~50. To such data we can apply the modern techniques in spectral energy distribution (SED) fitting to determine source redshifts, sometimes called ``photometric redshifts''. Low resolution prism observations of galaxy SED's provide a ...

  1. Synthesis and Photocatalytic Activity of Ag3PO4 Triangular Prism

    OpenAIRE

    Pengyu Dong; Yan Hao; Peiyang Gao; Entian Cui; Qinfang Zhang

    2015-01-01

    Ag3PO4 triangular prism was synthesized by a facile chemical precipitation approach by simply adjusting external ultrasonic condition. The as-synthesized Ag3PO4 triangular prism was characterized by X-ray diffraction pattern (XRD), field emission scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectra, and ultraviolet-visible diffuse reflectance (UV-vis DRS) absorption spectra. The photocatalytic activity of Ag3PO4 triangular prism was evaluated by photodegradation of or...

  2. PriSM: a primer selection and matching tool for amplification and sequencing of viral genomes

    OpenAIRE

    Yu, Qing; Ryan, Elizabeth M; Allen, Todd M.; Birren, Bruce W.; Henn, Matthew R.; Lennon, Niall J.

    2010-01-01

    Summary: PriSM is a set of algorithms designed to select and match degenerate primer pairs for the amplification of viral genomes. The design of panels of hundreds of primer pairs takes just hours using this program, compared with days using a manual approach. PriSM allows for rapid in silico optimization of primers for downstream applications such as sequencing. As a validation, PriSM was used to create an amplification primer panel for human immunodeficiency virus (HIV) Clade B.

  3. Left-Deviating Prism Adaptation in Left Neglect Patient: Reflexions on a Negative Result

    OpenAIRE

    Jacques Luauté; Sophie Jacquin-Courtois; Jacinta O'Shea; Laure Christophe; Gilles Rode; Dominique Boisson; Yves Rossetti

    2012-01-01

    Adaptation to right-deviating prisms is a promising intervention for the rehabilitation of patients with left spatial neglect. In order to test the lateral specificity of prism adaptation on left neglect, the present study evaluated the effect of left-deviating prism on straight-ahead pointing movements and on several classical neuropsychological tests in a group of five right brain-damaged patients with left spatial neglect. A group of healthy subjects was also included for comparison purpos...

  4. Mortality Risk Prediction by Application of PRISM Scoring System in Pediatric Intensive Care Unit

    OpenAIRE

    Mahdi Mohammadi; Afshin Fayyazi; Mohsen Raeisi; Noor Mohammad Noori; Ali Khajeh; Ghasem Miri-Aliabad

    2013-01-01

    Objective: The Pediatric Risk of Mortality (PRISM) score is one of the scores used by many pediatricians for prediction of the mortality risk in the pediatric intensive care unit (PICU). Herein, evaluate the efficacy of PRISM score in prediction of mortality rate in PICU.Methods: In this cohort study, 221 children admitted during an 18-month period to PICU, were enrolled. PRISM score and mortality risk were calculated. Follow up was noted as death or discharge. Results were analyzed by Kaplan...

  5. Urban Chagas disease in children and women in primary care centres in Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Guillermo Moscatelli

    2015-08-01

    Full Text Available The primary objective of this study was to estimate the prevalence of this disease in women of childbearing age and children treated at health centres in underserviced areas of the city of Buenos Aires. Demographic and Chagas disease status data were collected. Samples for Chagas disease serology were obtained on filter paper and the reactive results were confirmed with conventional samples. A total of 1,786 subjects were screened and 73 positive screening results were obtained: 17 were from children and 56 were from women. The Trypanosoma cruziinfection risk was greater in those individuals who had relatives with Chagas disease, who remember seeing kissing bugs, who were of Bolivian nationality or were born in the Argentine province of Santiago del Estero. The overall prevalence of Chagas disease was 4.08%. Due to migration, Chagas disease is currently predominantly urban. The observed prevalence requires health programme activities that are aimed at urban children and their mothers. Most children were infected congenitally, which reinforces the need for Chagas disease screening of all pregnant women and their babies in Argentina. The active search for new cases is important because the appropriate treatment in children has a high cure rate.

  6. Chagas disease: What is known and what should be improved: a systemic review

    Directory of Open Access Journals (Sweden)

    José Rodrigues Coura

    2012-06-01

    Full Text Available This study consists of a broad review on what is known and what should be improved regarding knowledge of Chagas disease, not only through analysis on the main studies published on the topics discussed, but to a large extent based on experience of this subject, acquired over the past 50 years (1961-2011. Among the subjects covered, we highlight the pathogenesis and evolution of infection by Trypanosoma cruzi, drugs in use and new strategies for treating Chagas disease; the serological tests for the diagnosis and the controls of cure the infection; the regional variations in prevalence, morbidity and response to treatment of the disease; the importance of metacyclogenesis of T. cruzi in different species of triatomines and its capacity to transmit Chagas infection; the risks of adaptation of wild triatomines to human dwellings; the morbidity and need for a surveillance and control program for Chagas disease in the Amazon region and the need to prioritize initiatives for controlling Chagas disease in Latin America and Mexico and in non-endemic countries, which is today a major international dilemma. Finally, we raise the need for to create a new initiative for controlling Chagas disease in the Gran Chaco, which involves parts of Argentina, Bolivia and Paraguay.

  7. Does my patient have chronic Chagas disease? Development and temporal validation of a diagnostic risk score

    Directory of Open Access Journals (Sweden)

    Pedro Emmanuel Alvarenga Americano do Brasil

    2016-06-01

    Full Text Available Abstract: INTRODUCTION With the globalization of Chagas disease, unexperienced health care providers may have difficulties in identifying which patients should be examined for this condition. This study aimed to develop and validate a diagnostic clinical prediction model for chronic Chagas disease. METHODS This diagnostic cohort study included consecutive volunteers suspected to have chronic Chagas disease. The clinical information was blindly compared to serological tests results, and a logistic regression model was fit and validated. RESULTS The development cohort included 602 patients, and the validation cohort included 138 patients. The Chagas disease prevalence was 19.9%. Sex, age, referral from blood bank, history of living in a rural area, recognizing the kissing bug, systemic hypertension, number of siblings with Chagas disease, number of relatives with a history of stroke, ECG with low voltage, anterosuperior divisional block, pathologic Q wave, right bundle branch block, and any kind of extrasystole were included in the final model. Calibration and discrimination in the development and validation cohorts (ROC AUC 0.904 and 0.912, respectively were good. Sensitivity and specificity analyses showed that specificity reaches at least 95% above the predicted 43% risk, while sensitivity is at least 95% below the predicted 7% risk. Net benefit decision curves favor the model across all thresholds. CONCLUSIONS: A nomogram and an online calculator (available at http://shiny.ipec.fiocruz.br:3838/pedrobrasil/chronic_chagas_disease_prediction/ were developed to aid in individual risk estimation.

  8. Group-delay Dispersion in Double-prism Pair and Limitation in Broadband Laser Pulses

    Institute of Scientific and Technical Information of China (English)

    程昭; 赵卫

    2002-01-01

    A general expression of group-delay dispersion is obtained without any approximation for a pair of double prisms with an arbitrary apex angle. This expression also includes the change of dispersion resulting from change in insertion of the prism material into the beam by translating prism-pairs. The high-order dispersion can be calculated by means of this expression. The limitation for generation of negative group-delay dispersion by use of prism-pairs is presented for ultrashort laser pulses with broadband spectrum.

  9. Ray-optical negative refraction and pseudoscopic imaging with Dove-prism arrays

    OpenAIRE

    Courtial, J.; Nelson, J

    2008-01-01

    A sheet consisting of an array of small, aligned Dove prisms can locally (on the scale of the width of the prisms) invert one component of the ray direction. A sandwich of two such Dove-prism sheets that inverts both transverse components of the ray direction is a ray-optical approximation to the interface between two media with refractive indices +n and –n. We demonstrate the simulated imaging properties of such a Dove-prism-sheet sandwich, including a demonstration of pseudoscopic imaging.

  10. PRISM -- A tool for modelling proton energy deposition in semiconductor materials

    International Nuclear Information System (INIS)

    This paper presents a description of, and test results from, a new PC based software simulation tool PRISM (Protons in Semiconductor Materials). The model describes proton energy deposition in complex 3D sensitive volumes of semiconductor materials. PRISM is suitable for simulating energy deposition in surface-barrier detectors and semiconductor memory devices, the latter being susceptible to Single-Event Upset (SEU) and Multiple-Bit Upset (MBU). The design methodology on which PRISM is based, together with the techniques used to simulate ion transport and energy deposition, are described. Preliminary test results used to analyze the PRISM model are presented

  11. The spectral characteristics of the splitting angle for double Wollaston prism

    Institute of Scientific and Technical Information of China (English)

    WU Wen-di; WANG Zhao-bing; WANG Hai-long; ZHANG Shan

    2009-01-01

    The spectral characteristics of the splitting angle and its asymmetry for double-Wollaston prism are analyzed theoretically. With the increase of the prism structure angle, the splitting angle of the double Wollaston prism and its asymmetry increase. However, the splitting angle decreases with the increase of the wavelength of incident light. The influence of the incident light wavelength on the splitting angle in the ultraviolet wave band is much greater than that in visible and near-infrared wave band. To verify the theoretical analysis, the characteristics of the double Wollaston prism are also studied experimentally.

  12. Membranous nephropathy PLA2R+ associated with Chagas disease.

    Science.gov (United States)

    Xavier-Júnior, José Cândido Caldeira; Silva, Vanessa Dos Santos; Viero, Rosa Marlene

    2015-01-01

    Chagas disease (CD) - a tropical parasitic disease caused by the protozoan Trypanosoma cruzi - is a major health problem in Latin America. The immune response against the parasite is responsible for chronic CD lesions. Currently, there are no reports of an association between CD and membranous nephropathy (MN). The detection of the phospholipase A2 receptor (PLA2R) as a target antigen in idiopathic MN can improve the differential diagnosis of primary and secondary forms of MN. The authors report the case of a male patient with positive serology for CD who presented sudden death and underwent autopsy. Histological sections of the heart showed multifocal inflammatory infiltrate composed mainly of mononuclear cells, leading to myocardiocytes necrosis and interstitial fibrosis. The kidneys showed a MN with positive expression for PLA2R. As far as we know, this is the first report of a case of primary MN in a patient with CD, with severe chronic cardiomyopathy and heart failure.

  13. Enfermedad de Chagas-Mazza congenita en Salta

    Directory of Open Access Journals (Sweden)

    Contreras Silvia

    1999-01-01

    Full Text Available Se estudió la infección por T. cruzi en mujeres embarazadas en la localidad de General Güemes, provincia de Salta. La misma fue del 12,3 %. El 8,8% de los recién nacidos estudiados tuvieron diagnóstico de Enfermedad de Chagas utilizando la técnica directa (microhematocrito. Todos fueron tratados con benznidazol a razón de 5mg/kg/día durante 30 dias. Todos presentaron anemia, que fue interpretada como reacción adversa medicamentosa. Se estima que la técnica directa representa la mejor opción para llevar a cabo el diagnóstico de esta enfermedad en el recién nacido. Se ha propuesto un flujograma para el seguimiento de la infección por T. cruzi en el recién nacido.

  14. [Association of encephalic vascular accidents and Chagas disease].

    Science.gov (United States)

    Lopes, E R; Marquez, J O; da Costa Neto, B; Menezes, A A; Chapadeiro, M E

    1991-01-01

    The frequency of strokes was studied in chronic chagasic and years of age, non-chagasic patients, older than 15 coming to necropsy in Uberaba, from 1979 than 1988. The study consisted of paired sex and age matched controls. Two hundred and eight pairs were analysed. Either ischemic or hemorrhagic strokes were found in 41 (19.7%) of the chagasics and in 55 (26.4%) of the non-chagasic, a difference not significant at the level of 5%. Twelve (75%) of the former had infarcts and 4 (25%) had brain hemorrhage; five (31.3%) of the non-chagasics had ischemic strokes and 11 (68.7%) had hemorrhagic strokes. The differences were significant to the level of 5%. The results indicate a high frequency of ischemic strokes in human Chagas' disease and demonstrate a lesser frequency of hemorrhagic stroke in chagasics when compared with non-chagasics. PMID:1841424

  15. Agrochemicals against malaria, sleeping sickness, leishmaniasis and Chagas disease.

    Directory of Open Access Journals (Sweden)

    Matthias Witschel

    Full Text Available In tropical regions, protozoan parasites can cause severe diseases with malaria, leishmaniasis, sleeping sickness, and Chagas disease standing in the forefront. Many of the drugs currently being used to treat these diseases have been developed more than 50 years ago and can cause severe adverse effects. Above all, resistance to existing drugs is widespread and has become a serious problem threatening the success of control measures. In order to identify new antiprotozoal agents, more than 600 commercial agrochemicals have been tested on the pathogens causing the above mentioned diseases. For all of the pathogens, compounds were identified with similar or even higher activities than the currently used drugs in applied in vitro assays. Furthermore, in vivo activity was observed for the fungicide/oomyceticide azoxystrobin, and the insecticide hydramethylnon in the Plasmodium berghei mouse model, and for the oomyceticide zoxamide in the Trypanosoma brucei rhodesiense STIB900 mouse model, respectively.

  16. Cerebral evoked potentials in human chronic Chagas' disease

    Directory of Open Access Journals (Sweden)

    O. M. Genovese

    1989-09-01

    Full Text Available Seventy five patients with the diagnosis of chronic Chagas' disease were studied by employing EPs techniques. Two of them had delayed arrival of the signal to the Erb's point and one to the spinal cord when looking at SEPs. TWo patients had increment of the time interval between waves 1st and IIIrd, when studying PEATs. These findings were interpreted as due to peripheral nerve fibers damage, a feature described in previous papers. The, most striking finding was the prolonged time interval between waves N13 and N20 (SEPs found in two patients and between waves IIIrd and Vth (PEAT seen in 7 affected subjects. These observations suggested the development of some sort of CNS involvement, perhaps related to myelin damage, in patients who reached the chronic state of the infection.

  17. Cost-effectiveness analysis in Chagas' disease vectors control interventions

    Directory of Open Access Journals (Sweden)

    A. M. Oliveira Filho

    1989-01-01

    Full Text Available After a large scale field trial performed in central Brazil envisaging the control of Chagas' disease vectors in an endemic area colonized by Triatoma infestans and T. sordida the cost-effectiveness analysis for each insecticide/formulation was performed. It considered the operational costs and the prices of insecticides and formulations, related to the activity and persistence of each one. The end point was considered to be less than 90% of domicilliary unitis (house + annexes free of infestation. The results showed good cost-effectiveness for a slow-release emulsifiable suspension (SRES based on PVA and containing malathion as active ingredient, as well as for the pyrethroids tested in this assay-cyfluthrin, cypermethrin, deltamethrin and permethrin.

  18. Radioisotopic exploration of patients suffering from chronic Chagas' disease

    International Nuclear Information System (INIS)

    The importance of Chagas' disease - a histic and haematic parasitosis endemic in extensive areas of Latin America, with 60 million people exposed to it and 20 million infected - stems from the high sickness and mortality rates affecting mainly rural and fringe populations. Nevertheless, progressive urbanization of the disease due to population migration and blood transfusion is being observed. The authors studied 56 cases of patients with Chagas' disease, 45 of whom were detected asymptomatically when donating blood by immunoserological reactions involving complement fixation and haemagglutination. Radiotracers were used to explore ventricular function in 56 cases; oesophageal transit in 29 cases; the upper urinary tract in 25 cases; and bladder function in 22 cases. All four procedures were applied to 19 patients. In 40 patients a study was made of the left and right ventricular function, the left being found altered in 17% of the cases, the right ventricular function in 22% and both in 25%. In 26 cases (65%) anomalies were encountered in at least one of the two ventricles. Oesophageal transit was altered in 20 patients, 16 of them asymptomatically. In 6 of them it was prolonged, in 4 it was adynamic and in 10 cases uncoordinated. The upper urinary tract showed abnormalities (pyelic dilation, pyelo-ureteral dyskinesia, ureteral dyskinesia, ureteral dilation and/or vesico-ureteral reflux) in 22 patients, in all cases asymptomatically. Bladder function was abnormal in 18 asymptomatic patients, basically represented by a residual decompensated cystopathy with a hypotonicity of different degrees. Of the 45 patients without symptoms detected when donating blood, there was alteration of ventricular function in 49%, of oesophageal transit in 68%, of the upper urinary tract in 90%, and of bladder function in 78%, with an overall figure of 66% abnormal examinations from 106 radioisotopic studies

  19. Asymmetrical prism for beam shaping of laser diode stacks.

    Science.gov (United States)

    Zeng, Xiaodong; Cao, Changqing; An, Yuying

    2005-09-10

    A beam-shaping scheme for a laser diode stack to obtain a flattop output intensity profile is proposed. The shaping element consists of an asymmetrical glass prism. The large divergence-angle compression in the direction perpendicular to the junction plane and the small divergence-angle expansion in the parallel direction are performed simultaneously by a single shaping element. The transformation characteristics are presented, and the optimization performance is investigated based on the ray-tracing method. Analysis shows that a flattop intensity profile can be obtained. This beam-shaping system can be fabricated easily and has a large alignment tolerance.

  20. Ultrafine Metal-Organic Right Square Prism Shaped Nanowires.

    Science.gov (United States)

    Otake, Ken-Ichi; Otsubo, Kazuya; Sugimoto, Kunihisa; Fujiwara, Akihiko; Kitagawa, Hiroshi

    2016-05-23

    We report the structural design and control of electronic states of a new series of ultrafine metal-organic right square prism-shaped nanowires. These nanowires have a very small inner diameter of about 2.0 Å, which is larger than hydrogen and similar to xenon atomic diameters. The electronic states of nanowires can be widely controlled by substitution of structural components. Moreover, the platinum homometallic nanowire shows a 100 times higher proton conductivity than a palladium/platinum heterometallic one depending on the electronic states. PMID:27080935

  1. Polarization manipulation holographic lithography by single refracting prism

    CERN Document Server

    Xu, Yi; Lan, Xiuming; Lu, Xiaoxu; Lan, Sheng; Wu, Lijun

    2011-01-01

    We propose a simple but effective strategy for polarization manipulation holographic lithography by single refractive prism. By tuning the polarization of single laser beam, we simply obtain a pill shape interference pattern where multiple modulated beams are needed in conventional holography lithography. Fabrication of large area pill shape two-dimensional polymer photonic crystals template using one beam and one shoot holography lithography is shown as an example. This integrated fabrication technique, for example, can release the crucial stability restrictions imposed on the multiple beams holography lithography.

  2. Inference with constrained hidden Markov models in PRISM

    DEFF Research Database (Denmark)

    Christiansen, Henning; Have, Christian Theil; Lassen, Ole Torp;

    2010-01-01

    A Hidden Markov Model (HMM) is a common statistical model which is widely used for analysis of biological sequence data and other sequential phenomena. In the present paper we show how HMMs can be extended with side-constraints and present constraint solving techniques for efficient inference....... Defining HMMs with side-constraints in Constraint Logic Programming has advantages in terms of more compact expression and pruning opportunities during inference. We present a PRISM-based framework for extending HMMs with side-constraints and show how well-known constraints such as cardinality and all...

  3. Chagas disease and globalization of the Amazon La enfermedad de Chagas y la globalización de la Amazonia

    Directory of Open Access Journals (Sweden)

    Roberto Briceño-León

    2007-01-01

    Full Text Available The increasing number of autochthonous cases of Chagas disease in the Amazon since the 1970s has led to fear that the disease may become a new public health problem in the region. This transformation in the disease's epidemiological pattern in the Amazon can be explained by environmental and social changes in the last 30 years. The current article draws on the sociological theory of perverse effects to explain these changes as the unwanted result of the shift from the "inward" development model prevailing until the 1970s to the "outward" model that we know as globalization, oriented by industrial forces and international trade. The current article highlights the implementation of five new patterns in agriculture, cattle-raising, mining, lumbering, and urban occupation that have generated changes in the environment and the traditional indigenous habitat and have led to migratory flows, deforestation, sedentary living, the presence of domestic animals, and changes in the habitat that facilitate colonization of human dwellings by vectors and the domestic and work-related transmission of the disease. The expansion of Chagas disease is thus a perverse effect of the globalization process in the Amazon.El incremento de casos autóctonos de la enfermedad de Chagas en la Amazonia a partir de los años setenta hace temer que pueda convertirse en un novedoso problema de salud pública en la región. Este cambio del patrón epidemiológico de la enfermedad en la región amazónica debe ser explicado por las transformaciones ambientales y sociales que han ocurrido en los pasados treinta años. Este artículo utiliza la teoría sociológica de los efectos perversos para explicar esos cambios como el resultado indeseado del cambio de modelo de desarrollo "hacia adentro", que había existido hasta los años setenta, por otro "hacia fuera" que está orientado por las fuerzas de la producción y el comercio internacional que conocemos como globalización. El art

  4. Update on Chagas' disease in Mexico Actualización sobre la enfermedad de Chagas en México

    Directory of Open Access Journals (Sweden)

    Eric Dumonteil

    1999-07-01

    Full Text Available Chagas' disease, caused by the protozoan parasite Trypanosoma cruzi, represents a major public health problem in most of the American continent. As transmission of the parasite is being interrupted in most of South America, the disease remains endemic in various areas of Mexico. We review here some of the information gathered in recent years. Seroprevalence of T. cruzi infection in humans remains relatively high in some areas, and there has been a general increase in the number of chronic cases reported to health authorities in recent years. In fact, chronic chagasic cardiomyopathy appears to be affecting a large number of patients with heart disease, but many cases may be misreported because of the unspecific nature of the clinical symptoms. Epidemiological monitoring of vector and reservoir populations, as well as of human cases is helping focus on endemic areas, but a better coordination and development of these efforts is still needed. Recent studies of parasite biology are in agreement with previous work showing the great diversity of parasite characteristics, and support the need for a regional approach to this zoonosis. Strong and continuing support from health and academic authorities is thus still needed to further improve our understanding of Chagas' disease in Mexico and implement efficient control programs.La enfermedad de Chagas, causada por el parásito protozoario Trypanosoma cruzi, constituye un importante problema de salud pública en el continente americano. La transmisión del parásito se ha ido interrumpiendo en la mayor parte de América del Sur, pero la enfermedad sigue siendo endémica en varias regiones de México. En este artículo se revisa la información más reciente sobre dicha enfermedad. La seroprevalencia de la infección por T. cruzi se ha mantenido a niveles relativamente altos en algunas regiones, y se observa un aumento general en el número de casos reportados a las autoridades de salud en los últimos a

  5. Chagas y SIDA, la importancia del diagnóstico precoz

    Directory of Open Access Journals (Sweden)

    Sergio R. Auger

    2005-01-01

    Full Text Available Objetivos: Evaluar las vías de contagio, la reactivación y la evolución de la enfermedad de Chagas en pacientes con HIV. Material y métodos Se incorporaron pacientes internados con SIDA y Chagas reactivo. Se evaluaron la epidemiología, la adicción a drogas, la reactivación de la enfermedad de Chagas y el órgano blanco más afectado, la demora del inicio de tratamiento antiparasitario y la evolución posterior. Se realizaron serologías, estudios parasitológicos en sangre y líquido cefalorraquídeo y exámenes complementarios cardiológicos y neurológicos. El estudio fue retrospectivo observacional y como método estadístico se emplearon las pruebas de chi cuadrado y exacta de Fischer. Resultados Se incluyeron en el estudio 8 pacientes con Chagas y SIDA. La vía de contagio de Chagas fue la vectorial en 5 pacientes (62,5% y la drogadicción endovenosa como hipótesis de alta probabilidad en 3 pacientes (37,5%. De estos últimos, 2 presentaron serología negativa para Chagas con parasitemias positivas. El motivo de internación fue reactivación de la enfermedad de Chagas en 5 pacientes (62,5% y de éstos, 4 sufrieron afección del sistema nervioso central y 1, miocarditis. De los 5 pacientes con agudización de la enfermedad de Chagas, 4 fallecieron a pesar del tratamiento con benznidazol. La iniciación de tratamiento demoró entre 7 y 15 días. Conclusiones La drogadicción endovenosa como nueva vía de contagio de la enfermedad de Chagas se transforma en una hipótesis de alta probabilidad, donde la serología no es relevante para el diagnóstico en pacientes con HIV+ y compromiso neurológico. La reactivación de la enfermedad de Chagas fue frecuente y la mortalidad elevada se relacionó con la falta de diagnóstico y el tratamiento tardío.

  6. The PRISM (Pliocene Palaeoclimate) reconstruction: Time for a paradigm shift

    Science.gov (United States)

    Dowsett, Harry J.; Robinson, Marci M.; Stoll, Danielle K.; Foley, Kevin M.; Johnson, Andrew L. A.; Williams, Mark; Riesselman, Christina

    2013-01-01

    Global palaeoclimate reconstructions have been invaluable to our understanding of the causes and effects of climate change, but single-temperature representations of the oceanic mixed layer for data–model comparisons are outdated, and the time for a paradigm shift in marine palaeoclimate reconstruction is overdue. The new paradigm in marine palaeoclimate reconstruction stems the loss of valuable climate information and instead presents a holistic and nuanced interpretation of multi-dimensional oceanographic processes and responses. A wealth of environmental information is hidden within the US Geological Survey's Pliocene Research,Interpretation and Synoptic Mapping (PRISM) marine palaeoclimate reconstruction, and we introduce here a plan to incorporate all valuable climate data into the next generation of PRISM products. Beyond the global approach and focus, we plan to incorporate regional climate dynamics with emphasis on processes, integrating multiple environmental proxies wherever available in order to better characterize the mixed layer, and developing a finer time slice within the Mid-Piacenzian Age of the Pliocene, complemented by underused proxies that offer snapshots into environmental conditions. The result will be a proxy-rich, temporally nested, process-oriented approach in a digital format—a relational database with geographic information system capabilities comprising a three-dimensional grid representing the surface layer, with a plethora of data in each cell.

  7. The PRISM (Pliocene palaeoclimate) reconstruction: time for a paradigm shift.

    Science.gov (United States)

    Dowsett, Harry J; Robinson, Marci M; Stoll, Danielle K; Foley, Kevin M; Johnson, Andrew L A; Williams, Mark; Riesselman, Christina R

    2013-10-28

    Global palaeoclimate reconstructions have been invaluable to our understanding of the causes and effects of climate change, but single-temperature representations of the oceanic mixed layer for data-model comparisons are outdated, and the time for a paradigm shift in marine palaeoclimate reconstruction is overdue. The new paradigm in marine palaeoclimate reconstruction stems the loss of valuable climate information and instead presents a holistic and nuanced interpretation of multi-dimensional oceanographic processes and responses. A wealth of environmental information is hidden within the US Geological Survey's Pliocene Research, Interpretation and Synoptic Mapping (PRISM) marine palaeoclimate reconstruction, and we introduce here a plan to incorporate all valuable climate data into the next generation of PRISM products. Beyond the global approach and focus, we plan to incorporate regional climate dynamics with emphasis on processes, integrating multiple environmental proxies wherever available in order to better characterize the mixed layer, and developing a finer time slice within the Mid-Piacenzian Age of the Pliocene, complemented by underused proxies that offer snapshots into environmental conditions. The result will be a proxy-rich, temporally nested, process-oriented approach in a digital format-a relational database with geographic information system capabilities comprising a three-dimensional grid representing the surface layer, with a plethora of data in each cell.

  8. Prism Foil from an LCD Monitor as a Tool for Teaching Introductory Optics

    Science.gov (United States)

    Planinsic, Gorazd; Gojkosek, Mihael

    2011-01-01

    Transparent prism foil is part of a backlight system in LCD monitors that are widely used today. This paper describes the optical properties of the prism foil and several pedagogical applications suitable for undergraduate introductory physics level. Examples include experiments that employ refraction, total internal reflection, diffraction and…

  9. Electron sharing and anion-π recognition in molecular triangular prisms.

    Science.gov (United States)

    Schneebeli, Severin T; Frasconi, Marco; Liu, Zhichang; Wu, Yilei; Gardner, Daniel M; Strutt, Nathan L; Cheng, Chuyang; Carmieli, Raanan; Wasielewski, Michael R; Stoddart, J Fraser

    2013-12-01

    Stacking on a full belly: Triangular molecular prisms display electron sharing among their triangularly arranged naphthalenediimide (NDI) redox centers. Their electron-deficient cavities encapsulate linear triiodide anions, leading to the formation of supramolecular helices in the solid state. Chirality transfer is observed from the six chiral centers of the filled prisms to the single-handed helices. PMID:24227594

  10. Diffraction theory applied to X-ray imaging with clessidra prism array lenses.

    Science.gov (United States)

    De Caro, Liberato; Jark, Werner

    2008-03-01

    Clessidra (hourglass) lenses, i.e. two large prisms each composed of smaller identical prisms or prism-like objects, can focus X-rays. As these lenses have a periodic structure perpendicular to the incident radiation, they will diffract the beam like a diffraction grating. Refraction in the prisms is responsible for blazing, i.e. for the concentration of the diffracted intensity into only a few diffraction peaks. It is found that the diffraction of coherent radiation in clessidra lenses needs to be treated in the Fresnel, or near-field, regime. Here, diffraction theory is applied appropriately to the clessidra structure in order to show that blazing in a perfect structure with partly curved prisms can indeed concentrate the diffracted intensity into only one peak. When the lens is entirely composed of identical perfect prisms, small secondary peaks are found. Nevertheless, the loss in intensity in the central peak will not lead to any significant widening of this peak. Clessidras with perfect prisms illuminated by full coherent X-ray radiation can then provide spatial resolutions, which are consistent with the increased aperture, and which are far below the height of the single small prisms.

  11. Investigating First Year Elementary Mathematics Teacher Education Students' Knowledge of Prism

    Science.gov (United States)

    Bozkurt, Ali; Koc, Yusuf

    2012-01-01

    The purpose of this study was to investigate first year elementary mathematics teacher education students' knowledge of prism. For this goal, the participants were asked to define the geometric concept of prism. The participants were 158 first year elementary mathematics teacher education students from a public university in Southern Turkey. The…

  12. Prism foil from an LCD monitor as a tool for teaching introductory optics

    International Nuclear Information System (INIS)

    Transparent prism foil is part of a backlight system in LCD monitors that are widely used today. This paper describes the optical properties of the prism foil and several pedagogical applications suitable for undergraduate introductory physics level. Examples include experiments that employ refraction, total internal reflection, diffraction and image formation in a nontrivial way and are therefore particularly useful for active learning strategies.

  13. Hierarchically triangular prism structured Co3O4: Self-supported fabrication and photocatalytic property

    Science.gov (United States)

    The formation of ammonium cobalt (II) phosphate was utilized to synthesize unprecedented 3D structures of Co3O4, triangular prisms and trunk-like structures, via a self-supported and organics-free method. The length of a triangular side of the prepared 3D triangular prisms is ~1...

  14. DEVELOPMENT OF A NEW OREGON PRECIPITATION MAP USING THE PRISM MODEL

    Science.gov (United States)

    Significant progress in our ability to distribute point monthly and annual precipitation data to a regular grid in complex terrain has recently been achieved through the development of PRISM (Precipitation-elevation Regressions on Independent Slopes Model) . PRISM is well suited ...

  15. Simultaneous adaptation of the thumb and index finger of the same hand to opposite prism displacements

    NARCIS (Netherlands)

    Schot, Willemijn D; Brenner, Eli; Smeets, Jeroen B J

    2014-01-01

    It only takes a few goal-directed hand movements to adapt one's movements to a prism-induced displacement of the visual scene. Adaptation to the displacement leads to errors in the opposite direction from the initial displacement when the prisms are removed. Such aftereffects are thought to arise fr

  16. Chagas' disease in the Amazon Basin: V. Periurban palms as habitats of Rhodnius robustus and Rhodnius pictipes - triatomine vectors of Chagas' disease

    Directory of Open Access Journals (Sweden)

    M. A. Miles

    1983-12-01

    Full Text Available Trypanosoma cruzi infected Rhodnius robustus and/or Rhodnius pictipes were commonly found, in large numbers, in the Brazilian Amazonian palms Maximiliana regia ("inajá", Acrocomia sclerocarpa ("mucajá" and Orbignya speciosa ("babaçu". The common opossum, Didelphis marsupialis, was the animal most frequently associated with triatomine infested palms. R. pictipes, frequently light-attracted into houses from palm trees, was the probable source of an acute case of Chagas' disease in the vicinity of Belém. It is considered that triatomine infested palms are likely to cause some cases of acute Chagas' disease in the States of Amazonas and Rondônia. Possible control methods are suggested.Rhodnius robustus e/ou Rhodnius pictipes, infectados com Trypanosoma cruzi foram comumente encontrados, em grande numero, nas palmeiras Maximiliana regia (inaja, Acrocomia sclerocarpa (mucaja e Orbignya speciosa (babacu na Amazonia brasileira. O marsupial Didelphis marsupialis foi o animal encontrado mais frequentemente nas palmeiras associadas a alta prevalencia de triatomineos. R. pictipes que e atraido pela luz nas residencias de palmeiras vizinhas, provavelmente e a fonte de um caso agudo de doenca de Chagas nas vizinhancas de Belem. Sugere-se que as palmeiras albergando triatomineos poderiam ser relacionadas com infeccoes humanas de doenca de Chagas nos Estados de Amazonas e Rondonia. Sugere-se, tambem, possiveis metodos de controle.

  17. Precision dispersion compensation for ultra-broadband bi-photons using a prism-pair with negative separation

    CERN Document Server

    Shaked, Yaakov; Pe'er, Avi

    2014-01-01

    The Brewster prism-pair is a major tool for dispersion control that produces tuned negative dispersion even when the prisms material has positive dispersion. We present a complementary technique for obtaining overall positive dispersion even when the material dispersion is negative, which is most useful for applications in the infrared, where the majority of the optical materials have negative dispersion. By adding a telescope between the prisms that images the first prism beyond the location of the second one, an effectively negative separation between the prisms can be obtained. This ability to flip the sign of the angular dispersion between the prisms provides a powerful new knob to the prism-pair system and allows higher degree of dispersion compensation. We demonstrate a prism-pair configuration, where both the 2nd and 4th order dispersion are compensated in the 1400-2400nm range, designed for a quantum optics experiment with ultra-broadband bi-photons.

  18. ePRISM: A case study in multiple proxy and mixed temporal resolution integration

    Science.gov (United States)

    Robinson, Marci M.; Dowsett, Harry J.

    2010-01-01

    As part of the Pliocene Research, Interpretation and Synoptic Mapping (PRISM) Project, we present the ePRISM experiment designed I) to provide climate modelers with a reconstruction of an early Pliocene warm period that was warmer than the PRISM interval (similar to 3.3 to 3.0 Ma), yet still similar in many ways to modern conditions and 2) to provide an example of how best to integrate multiple-proxy sea surface temperature (SST) data from time series with varying degrees of temporal resolution and age control as we begin to build the next generation of PRISM, the PRISM4 reconstruction, spanning a constricted time interval. While it is possible to tie individual SST estimates to a single light (warm) oxygen isotope event, we find that the warm peak average of SST estimates over a narrowed time interval is preferential for paleoclimate reconstruction as it allows for the inclusion of more records of multiple paleotemperature proxies.

  19. Relationship between Timing Jitter and Prism Separation in Mode-locked Solid State Lasers

    Institute of Scientific and Technical Information of China (English)

    LU Hong

    2001-01-01

    The function expression of the group delay dispersion (GDD) depending on the prism separation and the normal displacement is derived, and that the GDD is proportional to the prism separation and near to a linear function of the normal displacement in the case of small normal displacement are found. Then we discuss the timing jitter caused by the amplified spontaneous emission (ASE) which depends on the prism separation and the normal displacement. We find that the timing jitter is near to a linear function of the prism separation and can be regrded as a linear function of the normal displacement in the case of small normal displacement. Based on the theoretic work, we suggest an experimental setup to measure the relationship between the timing jitter and the prism separation or the normal displacement.

  20. Epilepsia e doença de chagas cronica

    Directory of Open Access Journals (Sweden)

    Edymar Jardim

    1981-03-01

    Full Text Available A síndrome epiléptica em chagásicos crônicos, foi referida raramente na literatura especializazda, não tendo sido feito até o momento, um estudo detalhado das suas manifestações. Partindo-se da premissa de que a moléstia de Chagas tem por substrato anatômico uma destruição neuronal, procurou-se comparar dois grupos de epilépticos, um dos quais com moléstia de Chagas crônica. Foram estudados 167 pacientes epilépticos, dos quais 44 eram comprovadamente chagásicos. O estudo permitiu coletar dados referentes à procedência dos pacientes, resultado soro-lógico, sexo, idade, época de incidência das manifestações epilépticas, elementos dos exames neurológicos, do líquido cefalorraqueano, eletrencefalográfico e os resultados da terapêutica anticonvulsivante. Como resultados principais destacamos o início tardio da epilepsia nos chagásicos, e o predomínio acentuado das crises parciais com sintomatologia elementar de tipo autonômico. O exame neurológico e o do líquido cefalorraqueano, apesar de apresentarem percentualmente nos seus resultados, taxas moderadamente mais elevadas na incidência de alterações, não caracterizaram síndromes neurológicas bem definidas. O exame eletrencefalográfico, revelou alterações sugestivas de comprometimento orgânico cerebral difuso. A terapêutica anticonvulsivante, baseada na utilização de hidantoinatos, barbitúricos, primidona e benzodiazepínicos, mostrou que o controle das crises foi mais difícil nos chagásicos, exigindo maiores quantidades de medicação, com resultados menos satisfatórios.

  1. Scintigraphy for the detection of myocardial damage in the indeterminate form of Chagas disease

    Energy Technology Data Exchange (ETDEWEB)

    Pedroso, Enio Roberto Pietra; Rezende, Nilton Alves de, E-mail: narezende@terra.com.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina; Abuhid, Ivana Moura [Instituto de Medicina Nuclear e Diagnostico Molecular, Belo Horizonte, MG (Brazil)

    2010-07-15

    Background: non-invasive cardiological methods have been used for the identification of myocardial damage in Chagas disease. Objective: to verify whether the rest/stress myocardial perfusion scintigraphy is able to identify early myocardial damage in the indeterminate form of Chagas disease. Methods: eighteen patients with the indeterminate form of Chagas Disease and the same number of normal controls, paired by sex and age, underwent rest/stress myocardial scintigraphy using sestamibi-99mTc, aiming at detecting early cardiac damage. Results: the results did not show perfusion or ventricular function defects in patients at the indeterminate phase of Chagas disease and in the normal controls, except for a patient who presented signs of ventricular dysfunction in the myocardial perfusion scintigraphy with electrocardiographic gating. Conclusion: the results of this study, considering the small sample size, showed that the rest/stress myocardial scintigraphy using sestamibi-99mTc is not an effective method to detect early myocardial alterations in the indeterminate form of Chagas disease (author)

  2. Socio-cultural aspects of Chagas disease: a systematic review of qualitative research.

    Directory of Open Access Journals (Sweden)

    Laia Ventura-Garcia

    Full Text Available BACKGROUND: Globally, more than 10 million people are infected with Trypanosoma cruzi, which causes about 20 000 annual deaths. Although Chagas disease is endemic to certain regions of Latin America, migratory flows have enabled its expansion into areas where it was previously unknown. Economic, social and cultural factors play a significant role in its presence and perpetuation. This systematic review aims to provide a comprehensive overview of qualitative research on Chagas disease, both in endemic and non-endemic countries. METHODOLOGY/PRINCIPAL FINDINGS: Searches were carried out in ten databases, and the bibliographies of retrieved studies were examined. Data from thirty-three identified studies were extracted, and findings were analyzed and synthesized along key themes. Themes identified for endemic countries included: socio-structural determinants of Chagas disease; health practices; biomedical conceptions of Chagas disease; patient's experience; and institutional strategies adopted. Concerning non-endemic countries, identified issues related to access to health services and health seeking. CONCLUSIONS: The emergence and perpetuation of Chagas disease depends largely on socio-cultural aspects influencing health. As most interventions do not address the clinical, environmental, social and cultural aspects jointly, an explicitly multidimensional approach, incorporating the experiences of those affected is a potential tool for the development of long-term successful programs. Further research is needed to evaluate this approach.

  3. Insights into the clinical and functional significance of cardiac autonomic dysfunction in Chagas disease

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Junqueira Junior

    2012-04-01

    Full Text Available INTRODUCTION: Exclusive or associated lesions in various structures of the autonomic nervous system occur in the chronic forms of Chagas disease. In the indeterminate form, the lesions are absent or mild, whereas in the exclusive or combined heart and digestive disease forms, they are often more pronounced. Depending on their severity these lesions can result mainly in cardiac parasympathetic dysfunction but also in sympathetic dysfunction of variable degrees. Despite the key autonomic effect on cardiovascular functioning, the pathophysiological and clinical significance of the cardiac autonomic dysfunction in Chagas disease remains unknown. METHODS: Review of data on the cardiac autonomic dysfunction in Chagas disease and their potential consequences, and considerations supporting the possible relationship between this disturbance and general or cardiovascular clinical and functional adverse outcomes. RESULTS: We hypothesise that possible consequences that cardiac dysautonomia might variably occasion or predispose in Chagas disease include: transient or sustained arrhythmias, sudden cardiac death, adverse overall and cardiovascular prognosis with enhanced morbidity and mortality, an inability of the cardiovascular system to adjust to functional demands and/or respond to internal or external stimuli by adjusting heart rate and other hemodynamic variables, and immunomodulatory and cognitive disturbances. CONCLUSIONS: Impaired cardiac autonomic modulation in Chagas disease might not be a mere epiphenomenon without significance. Indirect evidences point for a likely important role of this alteration as a primary predisposing or triggering cause or mediator favouring the development of subtle or evident secondary cardiovascular functional disturbances and clinical consequences, and influencing adverse outcomes.

  4. Triatominae Biochemistry Goes to School: Evaluation of a Novel Tool for Teaching Basic Biochemical Concepts of Chagas Disease Vectors

    Science.gov (United States)

    Cunha, Leonardo Rodrigues; de Oliveria Cudischevitch, Cecília; Carneiro, Alan Brito; Macedo, Gustavo Bartholomeu; Lannes, Denise; da Silva-Neto, Mário Alberto Cardoso

    2014-01-01

    We evaluate a new approach to teaching the basic biochemistry mechanisms that regulate the biology of Triatominae, major vectors of "Trypanosoma cruzi," the causative agent of Chagas disease. We have designed and used a comic book, "Carlos Chagas: 100 years after a hero's discovery" containing scientific information…

  5. The geological perspective of Italy and Chile by Abbot Juan Ignacio Molina between the 18th and 19th centuries La perspectiva geolgica del Abate Juan Ignacio Molina sobre Italia y Chile entre los siglos XVIII y XIX

    Directory of Open Access Journals (Sweden)

    Marco Menichetti

    2011-09-01

    , vegetables and animals within the framework of the then accepted philosophy of the Great Chain of Being. Because of his ideas and statements, apparently endowing animals and plants with human characteristics, Molina was denounced for and then cleared of heterodoxy. Abbot Molina made an important contribution to the study of Chile's Natural History, and to the South American natural sciences in general. Although Molina lived most of his life outside of Chile, he nurtured a deep love and pride for his country. The picture that emerges from his writings contributed to a large degree in acquainting the world with his native land and its native peoples.Las primeras observaciones geolgicas en Chile pueden ser trazadas a travs de Juan Ignacio Molina, un sacerdote jesuita quien haba nacido en Chile en 1740 y muri en Bolonia en 1829. l recibi una formacin acadmica con un fuerte aprendizaje hacia la filosofa, las humanidades y las ciencias en el Colegio Jesutico de Concepcin. En 1767, cuando todos los jesuitas fueron expulsados de Chile y de las colonias espaolas, se refugi en Italia, primero en Imola y posteriormente en Bolonia, donde ense griego en la Universidad y posteriormente ciencias naturales en el Archigimnasio. Durante su estada en Bolonia al final del siglo XVIII, la comunidad jesutica continu teniendo un rol en la enseanza de las ciencias a pesar de la ocupacin napolenica. En Bolonia, tan temprano como en el siglo XVI, Ulisse Adrovani desarroll nuevos conceptos en geologa con su estudio y coleccin sistemtica de fsiles. A comienzos del siglo XVIII, el naturalista y oceangrafo L. F. Marsili, y uno de los padres de la paleontologa, G. Monti, avanzaron sobre el trabajo de Aldrovandi y contribuyeron al crecimiento del Instituto de Ciencias y Museo de Historia Natural en la ciudad. Fue en este contexto natural que Molina public en 1782, en italiano, Saggio sulla storia naturale del Chile. El libro fue dividido en cuatro captulos, los primeros dos dedicados a las ciencias de la

  6. A VUV prism spectrometer for RICH radiator refractometry

    CERN Document Server

    Moyssides, P G; Fokitis, E

    2000-01-01

    A prism spectrometer has been developed to operate in the VUV wavelength range from 120 to 200 nm. It can be used as a pre- disperser in conjunction with a Fabry-Perot based gas refractometer. This instrument has also been used to measure the refractive index of the liquid radiator C/sub 6/F/sub 14/ in various spectral lines. This radiator is used in the RICH detectors of the DELPHI experiment and has been proposed for ALICE, and LHCb experiments. The spectral resolution of the system is improved as the wavelength decreases and the data are consistent with a wavelength accuracy about 0.4 nm at 140 nm. The results for the dispersion curve of the above liquid are presented. (17 refs).

  7. R&D proposal the prism plastic calorimeter:PPC

    CERN Document Server

    Dobrzynski, Ludwik; Marchand, P; Nédélec, P; Salin, P; CERN. Geneva. Detector Research and Development Committee

    1990-01-01

    This proposal supports two goals: First Goal_Demonstrate that current, widely used plastic technologies allow to design Prism Plastic Calorimeter (PPC) towers with a new "liquid crystal" type plastic called Vectra. It will be shown that this technique meets the requirements for a LHC calorimeter with warm liquids: safety, hermeticity, hadronic compensation, resolution and time response. Second Goal_ Describe how one can design a warm liquid calorimeter integrated into a LHC detector,and list the advantages of the PPC: low price, minimum of mechanical structures, minimum amount of dead space, easiness of mechanical assembly, accessibility to the electronics, possibility to recirculate the liquid. The absorber and the electronics being outside the liquid and easily accessible, one has maximum flexibility to define them. The R&D program we define here aims at showing the feasibility of these new ideas by building nine towers of twenty gaps and exposing them to electron and hadron beams.

  8. Optical device with conical input and output prism faces

    Science.gov (United States)

    Brunsden, Barry S.

    1981-01-01

    A device for radially translating radiation in which a right circular cylinder is provided at each end thereof with conical prism faces. The faces are oppositely extending and the device may be severed in the middle and separated to allow access to the central part of the beam. Radiation entering the input end of the device is radially translated such that radiation entering the input end at the perimeter is concentrated toward the output central axis and radiation at the input central axis is dispersed toward the output perimeter. Devices are disclosed for compressing beam energy to enhance drilling techniques, for beam manipulation of optical spatial frequencies in the Fourier plane and for simplification of dark field and color contrast microscopy. Both refracting and reflecting devices are disclosed.

  9. Cosmic topology of prism double-action manifolds

    International Nuclear Information System (INIS)

    The cosmic microwave background (CMB) anisotropies in spherical 3-spaces with a non-trivial topology are studied. This paper discusses the special class of the so-called double-action manifolds, which are for the first time analysed with respect to their CMB anisotropies. The CMB anisotropies are computed for all prism double-action manifolds generated by a binary dihedral and a cyclic group with a group order of up to 180 leading to 33 different topologies. Several spaces are found which show a suppression of the CMB anisotropies on large angular distances as it is found on the real CMB sky. It turns out that two of these spaces possess Dirichlet domains which are not very far from highly symmetric polyhedra like Platonic or Archimedean ones. (paper)

  10. Mass spectrometers based on a cone-shaped acromatic prism

    International Nuclear Information System (INIS)

    We have elaborated a mass spectrometer without lenses consisting of one conic achromatic prism. It has a specific mass dispersion which is equal to 67.5 mm/m per 1% change of mass. (By specific dispersion we mean linear dispersion related to the main path.) The pass of charged particles with different emittance is investigated with the help of integrating precise equations for tracks of charged particles in natural curvilinear coordinates. We have calculated the resolving power and aberration of a mass spectrometer for different beams of particles. It is evident that the mass spectrometer is particularly effective in use when we deal with rather wide ion beams having an insignificant angular divergence in the mean plane. (orig.)

  11. Acoustic Prism for Continuous Beam Steering Based on Piezoelectric Metamaterial

    CERN Document Server

    Xu, Jiawen

    2016-01-01

    This paper investigates an acoustic prism for continuous acoustic beam steering by a simple frequency sweep. This idea takes advantages of acoustic wave velocity shifting in metamaterials in the vicinity of local resonance. We apply this concept into the piezoelectric metamaterial consisting of host medium and piezoelectric LC shunt. Theoretical modeling and FEM simulations are carried out. It is shown that the phase velocity of acoustic wave changes dramatically in the vicinity of local resonance. The directions of acoustic wave can be adjusted continuously between 2 to 16 degrees by a simple sweep of the excitation frequency. Such an electro-mechanical coupling system has a feature of adjusting local resonance without altering the mechanical part of the system.

  12. Larmor labeling of neutron spin using superconducting Wollaston prisms

    Science.gov (United States)

    Li, Fankang

    Neutron spin Larmor labeling using magnetic Wollaston prisms (WP) provides a way to overcome some of the limitations arising from the nature of neutron beams: low flux and divergence. Using superconducting films and tapes, a series of strong, well-defined shaped magnetic fields can be produced due to both the zero-resistance and Meissner effect in superconductors. Using finite element simulations, the criterion to build a superconducting magnetic Wollaston prism with high encoding efficiency and low Larmor phase aberrations are presented. To achieve a high magnetic field and simplify the maintenance, we optimize the design using careful thermal analysis. The measured neutron spin flipping efficiency is measured to be independent of both the neutron wavelength and energizing current, which is a significant improvement over other devices with similar functions. A highly linear variation of the Larmor phase is measured across the device, which ensures a highly uniform encoding of scattering angles into the neutron spin Larmor phase. Using two WPs, the correlation function for a colloidal silica sample was measured by spin echo modulated small angle neutron scattering (SEMSANS) and agrees well with other techniques. Using Monte Carlo code (McStas), we further investigated the SEMSANS setup and showed the requirements to improve its performance. We have proposed a new technique to implement neutron spin echo on a triple axis neutron spectrometer to achieve high resolution measurements of the lifetime of dispersive phonon excitations. The spin echo is tuned by appropriate choice of magnetic fields instead of physically tilting the coils used in traditional methods. This new approach allows a higher energy resolution and a larger effective tilting angle and hence larger group velocity to be measured.

  13. Viability study of a multiplex diagnostic platform for Chagas disease

    Directory of Open Access Journals (Sweden)

    Leonardo Foti

    2009-07-01

    Full Text Available A new multiplex assay platform was evaluated to detect Trypanosoma cruzi infection using the recombinant antigens CRA, FRA, CRAFRA fusion and parasite lysate. The antigens presented different sensitivity and specificity in a singleplex test when compared to a serial dilution of two pools comprising 10 positive serum samples and one pool of 10 negative samples. The recombinant protein CRA presented lower sensitivity (55% in contrast to the 100% specificity and sensitivity of FRA, CRAFRA and T. cruzi lysate. These antigens also showed good results in a duplex test and the duplex test with CRAFRA/T. cruzi lysate showed better performance with 100% specificity and sensitivity, as well as a lower cut-off value in comparison to the other duplex test, FRA/T. cruzi lysate. Hence, when the antigens were used in duplex format, both tests showed decreased cut-off values and no interference between different bead sets, resulting in increasing sensitivity and specificity. The results of these multiplex tests show that they could be an alternative to singleplex detection for Chagas disease, and also indicate the necessity of using multiplex diagnostic tools to increase the sensitivity and specificity for diagnostic tests. Emerging data from the T. cruzi genome and from its ORFeome project will also allow the identification of new antigens for this disease detection application.

  14. Urbanization, land tenure security and vector-borne Chagas disease

    Science.gov (United States)

    Levy, Michael Z.; Barbu, Corentin M.; Castillo-Neyra, Ricardo; Quispe-Machaca, Victor R.; Ancca-Juarez, Jenny; Escalante-Mejia, Patricia; Borrini-Mayori, Katty; Niemierko, Malwina; Mabud, Tarub S.; Behrman, Jere R.; Naquira-Velarde, Cesar

    2014-01-01

    Modern cities represent one of the fastest growing ecosystems on the planet. Urbanization occurs in stages; each stage characterized by a distinct habitat that may be more or less susceptible to the establishment of disease vector populations and the transmission of vector-borne pathogens. We performed longitudinal entomological and epidemiological surveys in households along a 1900 × 125 m transect of Arequipa, Peru, a major city of nearly one million inhabitants, in which the transmission of Trypanosoma cruzi, the aetiological agent of Chagas disease, by the insect vector Triatoma infestans, is an ongoing problem. The transect spans a cline of urban development from established communities to land invasions. We find that the vector is tracking the development of the city, and the parasite, in turn, is tracking the dispersal of the vector. New urbanizations are free of vector infestation for decades. T. cruzi transmission is very recent and concentrated in more established communities. The increase in land tenure security during the course of urbanization, if not accompanied by reasonable and enforceable zoning codes, initiates an influx of construction materials, people and animals that creates fertile conditions for epidemics of some vector-borne diseases. PMID:24990681

  15. Chagas Disease Vector Control in Tupiza, Southern Bolivia

    Directory of Open Access Journals (Sweden)

    G Guillen

    1997-01-01

    Full Text Available Heavy domestic and peridomestic infestations of Triatoma infestans were controlled in two villages in southern Bolivia by the application of deltamethrin SC25 (2.5% suspension concentrate at a target dose of 25 mg a.i./m². Actual applied dose was monitored by HPLC analysis of filter papers placed at various heights on the house walls, and was shown to range from 0 to 59.6 about a mean of 28.5 mg a.i./m². Wall bioassays showed high mortality of T. infestans during the first month after the application of deltamethrin. Mortality declined to zero as summer temperatures increased, but reappeared with the onset of the following winter. In contrast, knockdown was apparent throughout the trial, showing no discernible temperature dependence. House infestation rates, measured by manual sampling and use of paper sheets to collect bug faeces, declined from 79% at the beginning of the trial to zero at the 6 month evaluation. All but one of the houses were still free of T. infestans at the final evaluation 12 months after spraying, although a small number of bugs were found at this time in 5 of 355 peridomestic dependencies. Comparative cost studies endorse the recommendation of large-scale application of deltamethrin, or pyrethroid of similar cost-effectiveness, as a means to eliminate domestic T. infestans populations in order to interrupt transmission of Chagas disease

  16. Viability study of a multiplex diagnostic platform for Chagas disease.

    Science.gov (United States)

    Foti, Leonardo; Fonseca, Bruna de Paula Fonseca e; Nascimento, Lilian Dias; Marques, Christiane de Fatima Silva; da Silva, Edmilson Domingos; Duarte, Cesar Augusto Barros; Probst, Christian M; Goldenberg, Samuel; Pinto, Antônio Gomes; Krieger, Marco Aurélio

    2009-07-01

    A new multiplex assay platform was evaluated to detect Trypanosoma cruzi infection using the recombinant antigens CRA, FRA, CRAFRA fusion and parasite lysate. The antigens presented different sensitivity and specificity in a singleplex test when compared to a serial dilution of two pools comprising 10 positive serum samples and one pool of 10 negative samples. The recombinant protein CRA presented lower sensitivity (55%) in contrast to the 100% specificity and sensitivity of FRA, CRAFRA and T. cruzi lysate. These antigens also showed good results in a duplex test and the duplex test with CRAFRA/T. cruzi lysate showed better performance with 100% specificity and sensitivity, as well as a lower cut-off value in comparison to the other duplex test, FRA/T. cruzi lysate. Hence, when the antigens were used in duplex format, both tests showed decreased cut-off values and no interference between different bead sets, resulting in increasing sensitivity and specificity. The results of these multiplex tests show that they could be an alternative to singleplex detection for Chagas disease, and also indicate the necessity of using multiplex diagnostic tools to increase the sensitivity and specificity for diagnostic tests. Emerging data from the T. cruzi genome and from its ORFeome project will also allow the identification of new antigens for this disease detection application. PMID:19753468

  17. Study of the hypothalamic - hypophyseal - thyroid axis by the administration of TRH to Chagas' disease patients

    International Nuclear Information System (INIS)

    The TSH and T3 response to synthetic TRH was evaluated in two groups of patients: normal and with Chagas' disease, from the urban area of Sao Paulo (Brazil). Plasma T4, PBI and TSH values were within the normal range, when compared with those found in the controls: So were the thyroid uptakes of 2 and 24 hours; the basal levels of T3 where within the normal range except in three subjects whose values were higher than normal. After TRH administration the amount of TSH secretion in patients with Chagas' disease was increased when compared to normal ones, while T3 secretion was unaltered. It is suggested that in the Chagas' disease there is an increase in the pituitary TSH, while the thyroid reserve is preserved. This increase could be due to a difference in the regulation rate of TRH, which is determined by the neuronal degeneration caused by the disease itself. (author)

  18. Congenital Chagas disease of second generation in Santiago, Chile. Report of two cases

    Directory of Open Access Journals (Sweden)

    SCHENONE Hugo

    2001-01-01

    Full Text Available Congenital Chagas disease (CChD has been reported in different countries, mostly in Latin America. In 1987 a fatal case of CChD of second generation (CChDSG was published. Within a period of six months - 1989-1990 - two cases of CChDSG were diagnosed and studied in the city of Santiago. Two premature newborns, sons of two sisters, with moderate liver and spleen enlargement, were found to have positive serology for Chagas disease and xenodiagnoses. The mothers, urban residents all their lives, without antecedents of triatomine bugs contact or blood transfusions, showed positive serology and xenodiagnoses. Their mother (grandmother of the infants, lived 20 years in a Northern rural Chagas disease endemic locality, in a triatomine infested house. Afterwards, she moved to Santiago, where she married and has resided up to now. Serology and xenodiagnoses were also positive. All the Trypanosoma cruzi infected individuals were successfully treated with nifurtimox.

  19. [José Lima Pedreira de Freitas and the redefinition and control of Chagas disease].

    Science.gov (United States)

    Rocha, Juan Stuardo Yazlle

    2016-08-01

    A brief overview of the evolution of knowledge about Chagas disease since its discovery by Carlos Chagas in 1909 until the mid-1940s is presented. The trajectory of physician Pedreira de Freitas and his growing involvement in research in the area led to his contributions to laboratory diagnosis - which lent consistency and security to epidemiological surveys of Chagas disease - and the redefinition of the scale of the disease in Brazil and the Americas with its terrible social and economic impact. His proposal for the disease prevention model - based on selective purging in the application of insecticide - was adopted nationally and internationally and made it possible to bring the disease under control in Brazil and other countries. He devoted himself with equal intensity to enhancing the teaching of medical practices in the community and was a pioneer in the implementation of preventive medicine in medical education in Brazil. PMID:27557035

  20. Multi-energy CT based on a prior rank, intensity and sparsity model (PRISM).

    Science.gov (United States)

    Gao, Hao; Yu, Hengyong; Osher, Stanley; Wang, Ge

    2011-11-01

    We propose a compressive sensing approach for multi-energy computed tomography (CT), namely the prior rank, intensity and sparsity model (PRISM). To further compress the multi-energy image for allowing the reconstruction with fewer CT data and less radiation dose, the PRISM models a multi-energy image as the superposition of a low-rank matrix and a sparse matrix (with row dimension in space and column dimension in energy), where the low-rank matrix corresponds to the stationary background over energy that has a low matrix rank, and the sparse matrix represents the rest of distinct spectral features that are often sparse. Distinct from previous methods, the PRISM utilizes the generalized rank, e.g., the matrix rank of tight-frame transform of a multi-energy image, which offers a way to characterize the multi-level and multi-filtered image coherence across the energy spectrum. Besides, the energy-dependent intensity information can be incorporated into the PRISM in terms of the spectral curves for base materials, with which the restoration of the multi-energy image becomes the reconstruction of the energy-independent material composition matrix. In other words, the PRISM utilizes prior knowledge on the generalized rank and sparsity of a multi-energy image, and intensity/spectral characteristics of base materials. Furthermore, we develop an accurate and fast split Bregman method for the PRISM and demonstrate the superior performance of the PRISM relative to several competing methods in simulations. PMID:22223929

  1. Left-Deviating Prism Adaptation in Left Neglect Patient: Reflexions on a Negative Result

    Directory of Open Access Journals (Sweden)

    Jacques Luauté

    2012-01-01

    Full Text Available Adaptation to right-deviating prisms is a promising intervention for the rehabilitation of patients with left spatial neglect. In order to test the lateral specificity of prism adaptation on left neglect, the present study evaluated the effect of left-deviating prism on straight-ahead pointing movements and on several classical neuropsychological tests in a group of five right brain-damaged patients with left spatial neglect. A group of healthy subjects was also included for comparison purposes. After a single session of exposing simple manual pointing to left-deviating prisms, contrary to healthy controls, none of the patients showed a reliable change of the straight-ahead pointing movement in the dark. No significant modification of attentional paper-and-pencil tasks was either observed immediately or 2 hours after prism adaptation. These results suggest that the therapeutic effect of prism adaptation on left spatial neglect relies on a specific lateralized mechanism. Evidence for a directional effect for prism adaptation both in terms of the side of the visuomanual adaptation and therefore possibly in terms of the side of brain affected by the stimulation is discussed.

  2. Multi-energy CT based on a prior rank, intensity and sparsity model (PRISM)

    International Nuclear Information System (INIS)

    We propose a compressive sensing approach for multi-energy computed tomography (CT), namely the prior rank, intensity and sparsity model (PRISM). To further compress the multi-energy image for allowing the reconstruction with fewer CT data and less radiation dose, the PRISM models a multi-energy image as the superposition of a low-rank matrix and a sparse matrix (with row dimension in space and column dimension in energy), where the low-rank matrix corresponds to the stationary background over energy that has a low matrix rank, and the sparse matrix represents the rest of distinct spectral features that are often sparse. Distinct from previous methods, the PRISM utilizes the generalized rank, e.g., the matrix rank of tight-frame transform of a multi-energy image, which offers a way to characterize the multi-level and multi-filtered image coherence across the energy spectrum. Besides, the energy-dependent intensity information can be incorporated into the PRISM in terms of the spectral curves for base materials, with which the restoration of the multi-energy image becomes the reconstruction of the energy-independent material composition matrix. In other words, the PRISM utilizes prior knowledge on the generalized rank and sparsity of a multi-energy image, and intensity/spectral characteristics of base materials. Furthermore, we develop an accurate and fast split Bregman method for the PRISM and demonstrate the superior performance of the PRISM relative to several competing methods in simulations. (papers)

  3. Estado actual de nuestros conocimientos sobre la enfermedad de chagas en la Republica Mexicana

    Directory of Open Access Journals (Sweden)

    Jorge Tay

    1981-06-01

    Full Text Available Se presentan los datos obtenidos de la revisión minuciosa en relación a enfermedad de Chagas de la literatura médica de la República Mexicana y extranjera desde el afio de 1939 en que por primeira vez se reporta a Trypanosoma cruzi en México, hasta el ano de 1976. Mediante mapas, tablas y cuadros se senalan las localidades en donde se han encontrado casos humanos, reservorios no humanos y transmisores. Se hacen comentários acerca de los resultados obtenidos y se seffala la importancia de incrementar los estúdios sobre enfermedades de Chagas en nuestro país.É a apresentação dos dados obtidos a partir de uma minuciosa revisão feita na literatura médica mexicana e estrangeira com relação à doença de Chagas no México. O estudo refere-se ao período de 1939 quando, pela primeira vez, menciona-se Trypanosoma cruzi no México, até 1976. Através de mapas, tabelas e quadros são mostrados os lugares onde foram encontrados casos humanos, reservatórios e transmissores. São feitos comentários sobre os resultados obtidos e é ressaltada a necessidade de ampliação dos estudos sobre a doença de Chagas no México.A thorough review of the literature is made regarding Chagas disease in Mexico and else- where since 1939, when Trypanosoma cruzi was first reported in this country until 1976. The location where human cases, non human reservoirs and transmitters have been found is pointed out by means of maps, tables and charts comments are made regarding the results reported. The importance of increasing the studies of Chagas' disease in our country is stressed.

  4. Aspectos neurológicos da moléstia de chagas

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    Fritz Köberle

    1967-09-01

    Full Text Available Carlos Chagas related in more than two 200 cases, what he called "nervous forms" of trypanosomiasis, that is neurological manifestations from central origin (idiotism, infantilism, pseudo-bulbar paralysis, aphasia, cerebellar ataxia, atetosis, espostic or paralytic diplegia, disbasia. At that time Chagas expressed his concepts as follows: "In relation to the frequency of trypanosomiasis nervous forms we have performed many observations which allow us to state that this disease is the one which causes the largest number of organic affections of the central nervous system, in human pathology". We are plenty convinced by Chagas's statement. By experiments on animals of laboratory we have very often noticed a rather varied neurological symptomatology, being worth point out identical syndromes to those observed by Chagas. Our autopsy material non-rarely include chronic Chagas cases presenting a most varied symtomatology. Among them we have named only three cases of discerebral nanism, a rather rare affection in other parts of the world and relatively frequent in our material. The fact which we have demonstrated, i.e., a relatively great decreasing of number of nervous cells in the peripheral system could happen in the central nervous system as well. Provided that there are only two quantitative works on neuron number diminishing in the central nervous system in mice and rats we decline to go into further details about central neuropathies in man. We emphasized the necessity to perform researches on this field by means of intimate collaboration between clinicians and pathologists, as the only way to confirm on scientific basis all that was observed by the panoramic and genial vision of Carlos Chagas.

  5. Evolution of the clinical and epidemiological knowledge about Chagas disease 90 years after its discovery

    Directory of Open Access Journals (Sweden)

    Prata Aluízio

    1999-01-01

    Full Text Available Three different periods may be considered in the evolution of knowledge about the clinical and epidemiological aspects of Chagas disease since its discovery: (a early period concerning the studies carried out by Carlos Chagas in Lassance with the collaboration of other investigators of the Manguinhos School. At that time the disease was described and the parasite, transmitters and reservoirs were studied. The coexistence of endemic goiter in the same region generated some confusion about the clinical forms of the disease; (b second period involving uncertainty and the description of isolated cases, which lasted until the 1940 decade. Many acute cases were described during this period and the disease was recognized in many Latin American countries. Particularly important were the studies of the Argentine Mission of Regional Pathology Studies, which culminated with the description of the Romaña sign in the 1930 decade, facilitating the diagnosis of the early phase of the disease. However, the chronic phase, which was the most important, continued to be difficult to recognize; (c period of consolidation of knowledge and recognition of the importance of Chagas disease. Studies conducted by Laranja, Dias and Nóbrega in Bambuí updated the description of Chagas heart disease made by Carlos Chagas and Eurico Villela. From then on, the disease was more easily recognized, especially with the emphasis on the use of a serologic diagnosis; (d period of enlargement of knowledges on the disease. The studies on denervation conducted in Ribeirão Preto by Fritz Köberle starting in the 1950 decade led to a better understanding of the relations between Chagas disease and megaesophagus and other visceral megas detected in endemic areas.

  6. The penta-prism LTP: A long-trace-profiler with stationary optical head and moving penta prism (abstract)

    International Nuclear Information System (INIS)

    Metrology requirements for optical components for third generation synchrotron sources are taxing the state-of-the-art in manufacturing technology. We have investigated a number of effect sources in a commercial figure measurement instrument, the Long Trace Profiler II (LTP II), and have demonstrated that, with some simple modifications, we can significantly reduce the effect of error sources and improve the accuracy and reliability of the measurement. By keeping the optical head stationary and moving a penta prism along the translation stage, the stability of the optical system is greatly improved, and the remaining error signals can be corrected by a simple reference beam subtraction. We illustrate the performance of the modified system by investigating the distortion produced by gravity on a typical synchrotron mirror and demonstrate the repeatability of the instrument despite relaxed tolerances on the translation stage

  7. Trypanosoma cruzi, causal agent of Chagas disease: The borderline between wild and domestic cycles in Venezuela.

    Directory of Open Access Journals (Sweden)

    Leidi eHerrera

    2014-11-01

    Full Text Available American trypanosomiasis or Chagas disease, caused by Trypanosoma cruzi, occurs between triatomine vectors and mammals, including man. T. cruzi has 150 Ma in America with almost 10 million of infected people today. The overlapping of its wild and domestic ecotopes is increasing. The host-parasite imbrications has been discerned by the study of infection patterns, transmissibility and transmission cycles in natural and laboratory models, through to parasitological and molecular tests. This article describes specific parasite niches, as plant biocenosis or biological corridors between domestic and wild ecotopes and helps distinguish Chagas disease risks and the borderline between wild and domestic transmission cycles, with emphasis on Venezuelan studies.

  8. Distantiae transmission of Trypanosoma cruzi: a new epidemiological feature of acute Chagas disease in Brazil.

    OpenAIRE

    Samanta Cristina das Chagas Xavier; André Luiz Rodrigues Roque; Daniele Bilac; Vitor Antônio Louzada de Araújo; Sócrates Fraga da Costa da Costa Neto; Elias Seixas Lorosa; Luiz Felipe Coutinho Ferreira da Silva; Ana Maria Jansen

    2014-01-01

    BACKGROUND: The new epidemiological scenario of orally transmitted Chagas disease that has emerged in Brazil, and mainly in the Amazon region, needs to be addressed with a new and systematic focus. Belém, the capital of Pará state, reports the highest number of acute Chagas disease (ACD) cases associated with the consumption of açaí juice. METHODOLOGY/PRINCIPAL FINDINGS: The wild and domestic enzootic transmission cycles of Trypanosoma cruzi were evaluated in the two locations (Jurunas and Va...

  9. Antigenicity and Diagnostic Potential of Vaccine Candidates in Human Chagas Disease

    OpenAIRE

    Shivali Gupta; Xianxiu Wan; Zago, Maria P.; Martinez Sellers, Valena C.; Silva, Trevor S.; Dadjah Assiah; Monisha Dhiman; Sonia Nuñez; Petersen, John R; Vázquez-Chagoyán, Juan C.; Jose G Estrada-Franco; Nisha Jain Garg

    2013-01-01

    BACKGROUND: Chagas disease, caused by Trypanosoma cruzi, is endemic in Latin America and an emerging infectious disease in the US and Europe. We have shown TcG1, TcG2, and TcG4 antigens elicit protective immunity to T. cruzi in mice and dogs. Herein, we investigated antigenicity of the recombinant proteins in humans to determine their potential utility for the development of next generation diagnostics for screening of T. cruzi infection and Chagas disease. METHODS AND RESULTS: Sera samples f...

  10. Surface Plasmon Excitation and Localization by Metal-Coated Axicon Prism

    Directory of Open Access Journals (Sweden)

    Atsushi Ono

    2012-02-01

    Full Text Available Collimated Gaussian beams are efficiently localized at the apex of a metal-coated axicon prism by surface plasmon excitations. We observed the light scattered at the apex and the light reflected by the prism. Intense scattered light was observed with the radial polarization incidence. Further, each incidence of the radial, azimuthal, and linear polarizations provided field distributions of bright and dark intensities in the reflected images according to the surface plasmon excitation. We have demonstrated that surface plasmon waves are excited at the sides of the prism in the Kretschmann configuration and that they converge to its apex.

  11. Does prism width from the shell prismatic layer have a random distribution?

    OpenAIRE

    Verrecchia, Eric P.; Vancolen, Séverine

    2009-01-01

    A study of the distribution of the prism width inside the prismatic layer of Unio tumidus (Philipsson 1788, Diss Hist-Nat, Berling, Lundæ) from Lake Neuchâtel, Switzerland, has been conducted in order to determine whether or not this distribution is random. Measurements of 954 to 1,343 prism widths (depending on shell sample) have been made using a scanning electron microscope in backscattered electron mode. A white noise test has been applied to the distribution of prism sizes (i.e. width). ...

  12. Doença de Chagas em Lassance, MG: Reavaliação clínico-epidemiológica 90 anos após a descoberta de Carlos Chagas Chagas' disease in Lassance, Minas Gerais State: Clinical-epidemiological re-evaluation ninety years after the discovery by Carlos Chagas

    Directory of Open Access Journals (Sweden)

    João Carlos Pinto Dias

    2002-04-01

    Full Text Available Analisa-se a trajetória da doença de Chagas em Lassance (município da descoberta de Carlos Chagas entre 1.908 a 2.001, através de registros históricos e pesquisas atuais. O município foi importante foco da tripanossomíase entre Chagas e os anos 1.980, mercê de infestação significativa das casas por Panstrongylus megistus e, mais tarde, Triatoma infestans, espécies que foram eficazmente controladas, nos últimos 20 anos. Importante no passado, a infecção chagásica é hoje residual, com uma prevalência geral de 5,03% e afetando basicamente os grupos etários elevados, não se encontrando soropositivos abaixo dos 20 anos de idade. O perfil clínico-epidemiológico dos chagásicos detectados é o habitual de áreas com transmissão interrompida, com a maioria dos casos em formas cardíacas benignas ou na forma crônica indeterminada, havendo ainda indicativos de formas digestivas, sendo a mortalidade ainda significativa, em grupos etários elevados. O município apresenta-se infestado por T. sordida, em baixas densidades e grande dispersão, não infectado por T. cruzi e restrito ao peridomicílio. Conclui-se que Lassance está hoje livre da transmissão da doença, devendo manter-se sob vigilância epidemiológica frente aos triatomíneos nativos no município e garantir-se a atenção médica às pessoas infectadas no passado.The history and present situation of Chagas' disease in Lassance (the county where Carlos Chagas discovered American trypanosomiasis were studied through a historical analysis and clinical and epidemiological research performed from 1999 to 2001. Lassance was an important focus of Chagas' disease from Carlos Chagas up until the 1980's, because of intensive infestation in dwellings by Panstrongylus megistus and Triatoma infestans, two important species which were efficiently controlled in the last twenty years. Human Chagas' disease was important in the past but today is only residual, affecting basically the

  13. Técnica do xenodiagnostico na molestia de Chagas

    Directory of Open Access Journals (Sweden)

    Emmanuel Dias

    1940-01-01

    Full Text Available O xenodiagnostico é um processo muito valioso para o diagnostico etiologico da moléstia de Chagas. Consiste em alimentar-se barbeiros normais em supótos portadores da infecção e determinar-se, depois, si eles adquirem ou não o parasitismo. Em cada região deve ser empregada, de preferência, o transmissor local mais importante. Três a seis ninfas famintas são geralmente empregadas em cada prova, devendo ficar em contacto com o doador até encherem-se completamente (15-30 minutos. Si o exame de fezes – espontaneamente eliminadas ou obtidas por punção anal – não revelar a presença de flagelados, os insetos devem ser dissecados 40 a 60 dias depois da sucção, para exame do conteúdo duodenal.Xenodiagnosis is a very valuable method for the etiological diagnosis of Chagas’s disease. It consists in allowing the clean insect transmitter to feed upon the suspected carrier, and in ascertaining whether the bugs become infected. The principal local vector is the most suitable species to be used in a given region. Three to six hungry nymphs are usually employed in each test and must feed until repletion (15-30 minutes. It flagellates are not detected in the faeces or in the rectal contents, obtained by anal puncture, insects are dissected 40-60 days after the and the duodenal contents is examined.

  14. Insecticide resistance in vector Chagas disease: evolution, mechanisms and management.

    Science.gov (United States)

    Mougabure-Cueto, Gastón; Picollo, María Inés

    2015-09-01

    Chagas disease is a chronic parasitic infection restricted to America. The disease is caused by the protozoa Trypanosoma cruzi, which is transmitted to human through the feces of infected triatomine insects. Because no treatment is available for the chronic forms of the disease, vector chemical control represents the best way to reduce the incidence of the disease. Chemical control has been based principally on spraying dwellings with insecticide formulations and led to the reduction of triatomine distribution and consequent interruption of disease transmission in several areas from endemic region. However, in the last decade it has been repeatedly reported the presence triatomnes, mainly Triatoma infestans, after spraying with pyrethroid insecticides, which was associated to evolution to insecticide resistance. In this paper the evolution of insecticide resistance in triatomines is reviewed. The insecticide resistance was detected in 1970s in Rhodnius prolixus and 1990s in R. prolixus and T. infestans, but not until the 2000s resistance to pyrthroids in T. infestans associated to control failures was described in Argentina and Bolivia. The main resistance mechanisms (i.e. enhanced metabolism, altered site of action and reduced penetration) were described in the T. infestans resistant to pyrethrods. Different resistant profiles were demonstrated suggesting independent origin of the different resistant foci of Argentina and Bolivia. The deltamethrin resistance in T. infestans was showed to be controlled by semi-dominant, autosomally inherited factors. Reproductive and developmental costs were also demonstrated for the resistant T. infestans. A discussion about resistance and tolerance concepts and the persistence of T. infestans in Gran Chaco region are presented. In addition, theoretical concepts related to toxicological, evolutionary and ecological aspects of insecticide resistance are discussed in order to understand the particular scenario of pyrethroid

  15. Barriers to treatment access for Chagas disease in Mexico.

    Directory of Open Access Journals (Sweden)

    Jennifer M Manne

    Full Text Available BACKGROUND: According to World Health Organization (WHO prevalence estimates, 1.1 million people in Mexico are infected with Trypanosoma cruzi, the etiologic agent of Chagas disease (CD. However, limited information is available about access to antitrypanosomal treatment. This study assesses the extent of access in Mexico, analyzes the barriers to access, and suggests strategies to overcome them. METHODS AND FINDINGS: Semi-structured in-depth interviews were conducted with 18 key informants and policymakers at the national level in Mexico. Data on CD cases, relevant policy documents and interview data were analyzed using the Flagship Framework for Pharmaceutical Policy Reform policy interventions: regulation, financing, payment, organization, and persuasion. Data showed that 3,013 cases were registered nationally from 2007-2011, representing 0.41% of total expected cases based on Mexico's national prevalence estimate. In four of five years, new registered cases were below national targets by 11-36%. Of 1,329 cases registered nationally in 2010-2011, 834 received treatment, 120 were pending treatment as of January 2012, and the treatment status of 375 was unknown. The analysis revealed that the national program mainly coordinated donation of nifurtimox and that important obstacles to access include the exclusion of antitrypanosomal medicines from the national formulary (regulation, historical exclusion of CD from the social insurance package (organization, absence of national clinical guidelines (organization, and limited provider awareness (persuasion. CONCLUSIONS: Efforts to treat CD in Mexico indicate an increased commitment to addressing this disease. Access to treatment could be advanced by improving the importation process for antitrypanosomal medicines and adding them to the national formulary, increasing education for healthcare providers, and strengthening clinical guidelines. These recommendations have important implications for other

  16. Molecular epidemiology of human oral Chagas disease outbreaks in Colombia.

    Directory of Open Access Journals (Sweden)

    Juan David Ramírez

    Full Text Available BACKGROUND: Trypanosoma cruzi, the causative agent of Chagas disease, displays significant genetic variability revealed by six Discrete Typing Units (TcI-TcVI. In this pathology, oral transmission represents an emerging epidemiological scenario where different outbreaks associated to food/beverages consumption have been reported in Argentina, Bolivia, Brazil, Ecuador and Venezuela. In Colombia, six human oral outbreaks have been reported corroborating the importance of this transmission route. Molecular epidemiology of oral outbreaks is barely known observing the incrimination of TcI, TcII, TcIV and TcV genotypes. METHODOLOGY AND PRINCIPAL FINDINGS: High-throughput molecular characterization was conducted performing MLMT (Multilocus Microsatellite Typing and mtMLST (mitochondrial Multilocus Sequence Typing strategies on 50 clones from ten isolates. Results allowed observing the occurrence of TcI, TcIV and mixed infection of distinct TcI genotypes. Thus, a majority of specific mitochondrial haplotypes and allelic multilocus genotypes associated to the sylvatic cycle of transmission were detected in the dataset with the foreseen presence of mitochondrial haplotypes and allelic multilocus genotypes associated to the domestic cycle of transmission. CONCLUSIONS: These findings suggest the incrimination of sylvatic genotypes in the oral outbreaks occurred in Colombia. We observed patterns of super-infection and/or co-infection with a tailored association with the severe forms of myocarditis in the acute phase of the disease. The transmission dynamics of this infection route based on molecular epidemiology evidence was unraveled and the clinical and biological implications are discussed.

  17. Chagas Disease: Challenges in Developing New Trypanocidal Lead Compounds [Doença de Chagas: Desafios no Desenvolvimento de Novas Substâncias Líderes Tripanomicidas

    Directory of Open Access Journals (Sweden)

    Fernando de C. da Silva

    2012-03-01

    Full Text Available Chagas disease cycle was fully elucidated by Carlos Chagas in 1909, when he reported his discovery to the scientific community in two seminal papers. Today remains innumerous factors that limit its therapeutic treatment. One of them is the lack of new drugs in the market since is well known that the existing drugs are poorly active with low efficacy and considerable side effects. Nowadays, many efforts have been done in combinatorial chemistry and synthesis of new compounds searching for new lead compounds. The present review intends to show that a wide variety of synthetic strategies are being used for the preparation of pharmaceutically active compounds against several strains of T. cruzi with a range of potential clinical applications.

  18. Effects of aspirin-triggered resolvin D1 on peripheral blood mononuclear cells from patients with Chagas' heart disease.

    Science.gov (United States)

    Ogata, Haline; Teixeira, Maxelle Martins; Sousa, Rodrigo Cunha de; Silva, Marcos Vinícius da; Correia, Dalmo; Rodrigues Junior, Virmondes; Levy, Bruce David; Rogério, Alexandre de Paula

    2016-04-15

    Chagas disease is caused by Trypanosoma cruzi (T. cruzi). In some patients with Chagas disease, symptoms progress to chronic chagasic cardiomyopathy. Endogenously, inflammation is resolved in the presence of lipid mediators such as aspirin-triggered RvD1 (AT-RvD1) which has anti-inflammatory and pro-resolution effects. Here, we demonstrated, for the first time, the effects of AT-RvD1 on T. cruzi antigen-stimulated peripheral blood mononuclear cells (PBMCs) from patients with Chagas heart disease. The levels of IFN-γ, TNF-α, IL-10, and IL-13 increased in PBMCs from cardiac-form Chagas patients in stage B1 (patients with fewer heart abnormalities) stimulated with T. cruzi antigen compared to those in non-stimulated PBMCs. AT-RvD1 reduced the IFN-γ concentrations in PBMCs from patients with Chagas disease stimulated with T. cruzi antigen compared to stimulated with T. cruzi antigen cells. AT-RvD1 treatment resulted in no observable changes in TNF-α, IL-10, and IL-13 levels. AT-RvD1 significantly decreased the percentage of necrotic cells and caused a significant reduction in the proliferation rate of T. cruzi antigen-stimulated PBMCs from patients with Chagas disease. These findings demonstrate that AT-RvD1 modulates the immune response in Chagas disease patients and might have potential to be used as an alternative approach for slowing the development of further heart damage.

  19. Comparação entre o reagente Chagas-latex e a imunofluorescência no diagnóstico sorológico da doença de Chagas na zona sul do Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Giovanni Baruffa

    1973-10-01

    Full Text Available Os Autores submeteram 142 amostras de soros de casos agudos e crônicos de Doença de Chagas, já examinados com o Reagente Chagas-Latex, ao exame de Imunofluorescência, obtendo correspondência de resultados em 139 (97,9%. O alto índice de fidelidade, provavelmente devido à ausência na zona de doenças que possam proporcionar resultados falsamente positivos, fez do Reagente Chagas-Latex um método simples e fácil para a triagem sorológica nos casos suspeitos em zona endêmica.

  20. FC-TRIPLEX Chagas/Leish IgG1: a multiplexed flow cytometry method for differential serological diagnosis of chagas disease and leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Andréa Teixeira-Carvalho

    Full Text Available Differential serological diagnosis of Chagas disease and leishmaniasis is difficult owing to cross-reactivity resulting from the fact that the parasites that cause these pathologies share antigenic epitopes. Even with optimized serological assays that use parasite-specific recombinant antigens, inconclusive test results continue to be a problem. Therefore, new serological tests with high sensitivity and specificity are needed. In the present work, we developed and evaluated the performance of a new flow cytometric serological method, referred to as FC-TRIPLEX Chagas/Leish IgG1, for the all-in-one classification of inconclusive tests. The method uses antigens for the detection of visceral leishmaniasis, localized cutaneous leishmaniasis, and Chagas disease and is based on an inverted detuned algorithm for analysis of anti-Trypanosomatidae IgG1 reactivity. First, parasites were label with fluorescein isothiocyanate or Alexa Fluor 647 at various concentrations. Then serum samples were serially diluted, the dilutions were incubated with suspensions of mixed labeled parasites, and flow cytometric measurements were performed to determine percentages of positive fluorescent parasites. Using the new method, we obtained correct results for 76 of 80 analyzed serum samples (95% overall performance, underscoring the outstanding performance of the method. Moreover, we found that the fluorescently labeled parasite suspensions were stable during storage at room temperature, 4 °C, and -20 °C for 1 year. In addition, two different lots of parasite suspensions showed equivalent antigen recognition; that is, the two lots showed equivalent categorical segregation of anti-Trypanosomatidae IgG1 reactivity at selected serum dilutions. In conclusion, we have developed a sensitive and selective method for differential diagnosis of Chagas disease, visceral leishmaniasis, and localized cutaneous leishmaniasis.

  1. Novo procedimento de xenodiagnóstico na forma crônica da doença de Chagas New xenodiagnostic procedure in chronic Chagas' disease

    Directory of Open Access Journals (Sweden)

    Saulo P. Almeida

    1976-01-01

    Full Text Available Xenodiagnósticos feitos com Triatoma infestans durante 24 horas consecutivas, a intervalos de duas horas, demonstraram o Trypanosoma cruzi em 9 de 10 pacientes suspeitos de infecção chagástica crônica.Positive xenodiagnostic was obtained in 9 out of 10 chronic Chagas' disease patients on which triatoma infestans were allowed to feed at 2hr intervals along a period of 24hr.

  2. Chagas' disease in the Brazilian Amazon: I - a short review Doença de Chagas na Amazônia Brasileira: I. revisão

    OpenAIRE

    José Rodrigues Coura; Angela Cristina Verissimo Junqueira; Cristina Maria Giordano; Ilra Renata Komoda Funatsu

    1994-01-01

    At least eighteen species of triatominae have been found in the Brazilian Amazon, nine of them naturally infected with Trypanosoma cruzi or "cruzi-like" trypanosomes and associated with numerous wild reservoirs. Despite the small number of human cases of Chagas' disease described to date in the Brazilian Amazon the risk that the disease will become endemic in this area is increasing for the following reasons: a) uncontrolled deforestation and colonization altering the ecological balance betwe...

  3. TEST METHOD FOR SINGLE INTERIOR RIGHT ANGLE IN A CORNER CUBE PRISM

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new test method for single interior right angle in a corner cube prism is presented. Some key points and parameters are analyzed and derived. The advantage of this method is concluded by comparing with some current conventional methods.

  4. A study on transmitted intensity's perturbance for air-spaced Glan-type polarizing prisms

    CERN Document Server

    Fan, J Y; Wu, F Q; Fan, Ji-Yang; Li, Hong-Xia; Wu, Fu-Quan

    2003-01-01

    The explanation for the perturbance of the transmitted intensity for air-spaced Glan-type polarizing prisms with varying rotation angle newly observed in the experiment is given. It is found that the transmitted intensity depends sensitively on the angle of incidence at the cut of the Glan-type prism. The minute fluctuation for values of the angle of incidence during the rotation of the stepmotor gives rise to the perturbance. The relation between the perturbance and the wavelength and the thickness of the air-gap is carefully investigated. Study shows that the disturbance for the Glan-Foucault prism is much stronger than that for the Glan-Taylor prism, as the experimental results have indicated. Theoretical results are perfectly in accordance with the experimental results. Effective measures for reducing the disturbance are presented.

  5. Finite layer and triangular prism element method to subsidence prediction and stress analysis in underground mining

    Institute of Scientific and Technical Information of China (English)

    LIU Li-min(刘立民); LIU Han-long(刘汉龙); LIAN Chuan-jie(连传杰)

    2003-01-01

    The application of the finite layer & triangular prism element method to the 3D ground subsidence and stress analysis caused by mining is presented. The layer elements and the triangular prism elements have been alternatively used in the numerical simulation system, the displacement pattern, strain matrix, elastic matrix, stiffness matrix, load matrix and the stress matrix of the layer element and triangular prism element have been presented. By means of the Fortran90 programming language, a numerical simulation system based on finite layer & triangular prism element have been built up, and this system is suitable for subsidence prediction and stress analysis of all mining condition and mining methods. Comparing with the infinite element method, this approach dramatically reduces the size of the set of equations that need to be solved, and greatly reduces the amount of data preparation required. It not only saves the internal storage, and the computation time, but also decreases the cost.

  6. Prism-assisted inclined UV lithography for 3D microstructure fabrication

    International Nuclear Information System (INIS)

    A prism-assisted inclined ultraviolet (UV) lithography technique is introduced for the fabrication of three-dimensional (3D) microstructures. Slanted structures with exposure angles ranging from 0° to 60° in SU-8 photoresist have been easily achieved without immersion in the index matching liquid. The fabrication process of multidirectional slanted structures can be simplified by one-step UV exposure using a prism with multidirectional side surfaces. A corner prism and a cone prism have been used in our experiment to demonstrate this concept. Upside-down tripod structures and horn structures have been fabricated in one-step exposures. The effective exposure area as one key parameter of the one-step exposure is analyzed for practical applications. Examples of various 3D microstructures fabricated by this method are presented. (paper)

  7. Improvement of Mental Imagery after Prism Exposure in Neglect: A Case Study

    Directory of Open Access Journals (Sweden)

    Gilles Rode

    1999-01-01

    Full Text Available Previous work has shown that various symptoms of unilateral neglect, including the pathological shift of the subjective midline to the right, may be improved by a short adaptation period to a prismatic shift of the visual field to the right. We report here the improvement of imagined neglect after prism exposure in a patient with a left unilateral neglect. Despite a strong neglect observed for mental images as well as for conventional tests, the mental evocation of left-sided information from an internal image of the map of France map was fully recovered following prism adaptation to the right. This improvement could not be explained by the alteration of visuomotor responses induced by the prism adaptation. Prism adaptation may therefore act not only on sensory-motor levels but also on a higher cognitive level of mental space representation and/or exploration.

  8. PERANCANGAN DAN IMPLEMENTASI SISTEM PENGUKURAN KINERJA DENGAN METODE PERFORMANCE PRISM (Studi Kasus pada Hotel X)

    OpenAIRE

    Iwan Vanany; Dian Tanukhidah

    2004-01-01

    This article described a result of research design of performance measurement system in hotel business with Performance Prism Model. As long as, performance measurement system at hotel X not yet representatived organization performance according to comprehensif and integrated. Because of needed redesign performance measurement system with new model. From the objective condition of hotel X, Performance Prism model more representative than others. The result of design described that stakeholder...

  9. Fusional Vergence Detected by Prism Bar and Synoptophore in Chinese Childhood Intermittent Exotropia

    OpenAIRE

    2015-01-01

    Purpose. To measure the changes in fusional vergence in Chinese children with intermittent exotropia (IXT) and the association with the control of IXT. Methods. Ninety-two patients with IXT (8–15 years old) were compared with 86 controls. Exodeviation control was evaluated using the Revised Newcastle Control Score. Angle of deviation was measured using prism and alternate cover testing at distance and near. Fusional vergence was measured using prism bar and synoptophore. This study was regist...

  10. PRISM (Polarized Radiation Imaging and Spectroscopy Mission): an extended white paper

    OpenAIRE

    PRISM Collaboration

    2014-01-01

    PRISM (Polarized Radiation Imaging and Spectroscopy Mission) was proposed to ESA in May 2013 as a large-class mission for investigating within the framework of the ESA Cosmic Vision program a set of important scientific questions that require high resolution, high sensitivity, full-sky observations of the sky emission at wavelengths ranging from millimeter-wave to the far-infrared. PRISM's main objective is to explore the distant universe, probing cosmic history from very early times until no...

  11. The dual Jacobian of a generalised tetrahedron, and volumes of prisms

    OpenAIRE

    Kolpakov, Alexander; Murakami, Jun

    2014-01-01

    We derive an analytic formula for the dual Jacobian matrix of a generalised hyperbolic tetrahedron. Two cases are considered: a mildly truncated and a prism truncated tetrahedron. The Jacobian for the latter arises as an analytic continuation of the former, that falls in line with a similar behaviour of the corresponding volume formulae. Also, we obtain a volume formula for a hyperbolic $n$-gonal prism: the proof requires the above mentioned Jacobian, employed in the analysis of the edge leng...

  12. Nitridation aspects of a basal and a prism plane textured Ti film

    International Nuclear Information System (INIS)

    High dose nitrogen implantation into a basal and a prism plane textured Ti film show differences in their end products. While the basal plane textured Ti film undergoes complete transformation to δ-TiN for a dose of 3 x 1017 ions/cm2, the prism plane textured film has a mixture of Ti and TiN for the same dose. The results indicate that the texture of the starting material has synergistic effects on the phase transformation. (author)

  13. Effects of prism adaptation on motor-intentional spatial bias in neglect

    OpenAIRE

    Fortis, Paola; Chen, Peii; Goedert, Kelly M.; Barrett, Anna M.

    2011-01-01

    Prism adaptation may alleviate some symptoms of spatial neglect. However, the mechanism through which this technique works is still unclear. The current study investigated whether prism adaptation differentially affects dysfunction in perceptual-attentional “where” versus motor-intentional “aiming” bias. Five neglect patients performed a line bisection task in which lines were viewed under both normal and right-left reversed viewing conditions, allowing for the fractionation of “where” and “a...

  14. Mode of death on Chagas heart disease: comparison with other etiologies. a subanalysis of the REMADHE prospective trial.

    Directory of Open Access Journals (Sweden)

    Silvia M Ayub-Ferreira

    Full Text Available Sudden death has been considered the main cause of death in patients with Chagas heart disease. Nevertheless, this information comes from a period before the introduction of drugs that changed the natural history of heart failure. We sought to study the mode of death of patients with heart failure caused by Chagas heart disease, comparing with non-Chagas cardiomyopathy.We examined the REMADHE trial and grouped patients according to etiology (Chagas vs non-Chagas and mode of death. The primary end-point was all-cause, heart failure and sudden death mortality; 342 patients were analyzed and 185 (54.1% died. Death occurred in 56.4% Chagas patients and 53.7% non-Chagas patients. The cumulative incidence of all-cause mortality and heart failure mortality was significantly higher in Chagas patients compared to non-Chagas. There was no difference in the cumulative incidence of sudden death mortality between the two groups. In the Cox regression model, Chagas etiology (HR 2.76; CI 1.34-5.69; p = 0.006, LVEDD (left ventricular end diastolic diameter (HR 1.07; CI 1.04-1.10; p<0.001, creatinine clearance (HR 0.98; CI 0.97-0.99; p = 0.006 and use of amiodarone (HR 3.05; CI 1.47-6.34; p = 0.003 were independently associated with heart failure mortality. LVEDD (HR 1.04; CI 1.01-1.07; p = 0.005 and use of beta-blocker (HR 0.52; CI 0.34-0.94; p = 0.014 were independently associated with sudden death mortality.In severe Chagas heart disease, progressive heart failure is the most important mode of death. These data challenge the current understanding of Chagas heart disease and may have implications in the selection of treatment choices, considering the mode of death.ClinicalTrials.gov NCT00505050 (REMADHE.

  15. Association of the Functional MICA-129 Polymorphism With the Severity of Chronic Chagas Heart Disease.

    Science.gov (United States)

    Ayo, Christiane Maria; Oliveira, Amanda Priscila de; Camargo, Ana Vitória da Silveira; Mattos, Cinara Cássia Brandão de; Bestetti, Reinaldo Bulgarelli; Mattos, Luiz Carlos de

    2015-10-15

    MICA-129 polymorphism affects the binding affinity of MICA molecules with the NKG2D receptor and influences effector cell function. The genotype met/met was associated with the severity of left ventricular systolic dysfunction (LVSD) in patients with chronic Chagas heart disease, while the val/val genotype was associated with the absence of LVSD.

  16. Chagas' Disease and HIV Co-infection: Genotypic Characterization of the Trypanosoma cruzi Strain

    Directory of Open Access Journals (Sweden)

    Pacheco Raquel S

    1998-01-01

    Full Text Available In the past few years, new aspects of the immunopathology of Chagas' disease have been described in immunosuppressed patients, such as fatal central nervous system lesions related to the reactivation of the parasite. This article is the first description of the genotypic characterization, at the strain level, of Trypanosoma cruzi isolated from a patient with Chagas` disease/AIDS co-infection. The presence of four hypodense lesions was observed in the cranial compute tomographic scan. The diagnosis of AIDS was assessed by the detection of anti-HIV antibodies using enzyme-linked immunosorbent assay (ELISA and Western blot techniques. The CD4+ lymphocyte counts were maintained under 200 cells/mm3 during one year demonstrating the severity of the state of immunosuppression. Chagas' disease was confirmed by serological and parasitological methods. Trypomastigote forms were visualized in a thick blood smear. The parasite isolated is genotypically similar to the CL strain. The paper reinforces that cerebral Chagas' disease can be considered as another potential opportunistic infection in AIDS resulting from the reactivation of a dormant T. cruzi infection acquired years earlier.

  17. Update on oral Chagas disease outbreaks in Venezuela: epidemiological, clinical and diagnostic approaches

    Science.gov (United States)

    de Noya, Belkisyolé Alarcón; Díaz-Bello, Zoraida; Colmenares, Cecilia; Ruiz-Guevara, Raiza; Mauriello, Luciano; Muñoz-Calderón, Arturo; Noya, Oscar

    2015-01-01

    Orally transmitted Chagas disease has become a matter of concern due to outbreaks reported in four Latin American countries. Although several mechanisms for orally transmitted Chagas disease transmission have been proposed, food and beverages contaminated with whole infected triatomines or their faeces, which contain metacyclic trypomastigotes of Trypanosoma cruzi, seems to be the primary vehicle. In 2007, the first recognised outbreak of orally transmitted Chagas disease occurred in Venezuela and largest recorded outbreak at that time. Since then, 10 outbreaks (four in Caracas) with 249 cases (73.5% children) and 4% mortality have occurred. The absence of contact with the vector and of traditional cutaneous and Romana’s signs, together with a florid spectrum of clinical manifestations during the acute phase, confuse the diagnosis of orally transmitted Chagas disease with other infectious diseases. The simultaneous detection of IgG and IgM by ELISA and the search for parasites in all individuals at risk have been valuable diagnostic tools for detecting acute cases. Follow-up studies regarding the microepidemics primarily affecting children has resulted in 70% infection persistence six years after anti-parasitic treatment. Panstrongylus geniculatus has been the incriminating vector in most cases. As a food-borne disease, this entity requires epidemiological, clinical, diagnostic and therapeutic approaches that differ from those approaches used for traditional direct or cutaneous vector transmission. PMID:25946155

  18. Integrated control of Chagas disease for its elimination as public health problem - A Review

    Science.gov (United States)

    Sosa-Estani, Sergio; Segura, Elsa Leonor

    2015-01-01

    Chagas disease or American trypanosomiasis is, together with geohelminths, the neglected disease that causes more loss of years of healthy life due to disability in Latin America. Chagas disease, as determined by the factors and determinants, shows that different contexts require different actions, preventing new cases or reducing the burden of disease. Control strategies must combine two general courses of action including prevention of transmission to prevent the occurrence of new cases (these measures are cost effective), as well as opportune diagnosis and treatment of infected individuals in order to prevent the clinical evolution of the disease and to allow them to recuperate their health. All actions should be implemented as fully as possible and with an integrated way, to maximise the impact. Chagas disease cannot be eradicated due because of the demonstrated existence of infected wild triatomines in permanent contact with domestic cycles and it contributes to the occurrence of at least few new cases. However, it is possible to interrupt the transmission of Trypanosoma cruzi in a large territory and to eliminate Chagas disease as a public health problem with a dramatic reduction of burden of the disease. PMID:25993503

  19. Chagas' disease: study of congenital transmission in cases of acute maternal infection

    Directory of Open Access Journals (Sweden)

    Moretti Edgardo

    2005-01-01

    Full Text Available We studied three pregnant women with acute chagasic infection. Two patients, infected in the third trimester of pregnancy, had uninfected children. The third patient, infected earlier, had an infected newborn. These results encourage research on risk factors of transmission and on medical decisions concerning pregnant women with acute Chagas' disease.

  20. Science, health and development: Chagas disease in Brazil, 1943-1962.

    Science.gov (United States)

    Kropf, S Petraglia

    2005-12-01

    The present paper discusses the historical construction and legitimacy of Chagas disease as a distinct nosological entity and as a public health issue in Brazil. It focuses on the activities of a group of researchers from Oswaldo Cruz Institute who worked at the Centre for the Study and Prevention of Chagas disease, located in Bambuí, Minas Gerais. Led in the 1940s and 50s by Emmanuel Dias, disciple of Carlos Chagas, the group made important contributions to the clinical characterization of Chagas disease as a cardiac illness, established the fact that it was technically possible to control the disease by using residual insecticides, and engaged in intense political mobilization to have the disease included as part of the Health Ministry sanitation campaigns. My hypothesis is that the group's work was a determining factor in the overcoming of certain unresolved controversies that had surrounded the medical and social identity of the disease since the 1920s. I examine to what extent this process was directly linked both to post-war optimism over new possibilities of combating infectious diseases and to the national and international debate on the relation between health and economic and social development.

  1. Situação atual da doença de Chagas na Guiana Francesa

    Directory of Open Access Journals (Sweden)

    Philippe Esterre

    1987-09-01

    Full Text Available Localizada entre dois focos endêmicos da doença de Chagas, a Venezuela e o Brasil, a Guiana Francesa conheceu poucos casos dessa afecção de 1940 até 1956. Um inquérito sorológico, utilizando-se uma pesquisa ativa sobre pacientes cardiopáticos e uma pesquisa passiva, permitiu evidenciar a existência de dois casos autóctones. Apesar da presença de vetores domésticos, o risco da doença de Chagas na Guiana Francesa parece limitado à aparição episódica de escassos casos humanos.Although located between two endemic areas of Chagas' disease (Venezuela and Brazil, French Guiana recorded only few cases of this infection between 1940 and 1956. A serological survey, using either active detection in cardiopathic patients or a passive one resulted in the finding of two autochthonous cases. In spite ofthe presence of a peridomiciliary cycle the risk of Chagas' disease in French Guiana seems to be limited to the episodic occurrence of rare sporadic human cases.

  2. Socio-Cultural Aspects of Chagas Disease: a Systematic Review of Qualitative Research

    NARCIS (Netherlands)

    L. Ventura-Garcia; M. Roura; C. Pell; E. Posada; J. Gascón; E. Aldasoro; J. Muñoz; R. Pool

    2013-01-01

    Background: Globally, more than 10 million people are infected with Trypanosoma cruzi, which causes about 20 000 annual deaths. Although Chagas disease is endemic to certain regions of Latin America, migratory flows have enabled its expansion into areas where it was previously unknown. Economic, soc

  3. The endless race between Trypanosoma cruzi and host immunity: lessons for and beyond Chagas disease.

    Science.gov (United States)

    Junqueira, Caroline; Caetano, Braulia; Bartholomeu, Daniella C; Melo, Mariane B; Ropert, Catherine; Rodrigues, Maurício M; Gazzinelli, Ricardo T

    2010-09-15

    Infection with the protozoan parasite Trypanosoma cruzi, the agent of Chagas disease, is characterised by a variable clinical course - from symptomless cases to severe chronic disease with cardiac and/or gastrointestinal involvement. The variability in disease outcome has been attributed to host responses as well as parasite heterogeneity. In this article, we review studies indicating the importance of immune responses as key determinants of host resistance to T. cruzi infection and the pathogenesis of Chagas disease. Particular attention is given to recent studies defining the role of cognate innate immune receptors and immunodominant CD8+ T cells that recognise parasite components - both crucial for host-parasite interaction and disease outcome. In light of these studies we speculate about parasite strategies that induce a strong and long-lasting T-cell-mediated immunity but at the same time allow persistence of the parasite in the vertebrate host. We also discuss what we have learned from these studies for increasing our understanding of Chagas pathogenesis and for the design of new strategies to prevent the development of Chagas disease. Finally, we highlight recent studies employing a genetically engineered attenuated T. cruzi strain as a vaccine shuttle that elicits potent T cell responses specific to a tumour antigen and protective immunity against a syngeneic melanoma cell line.

  4. Oral Transmission of Chagas Disease by Consumption of Açaí Palm Fruit, Brazil

    OpenAIRE

    Nóbrega, Aglaêr A.; Garcia, Marcio H.; Tatto, Erica; Marcos T Obara; Costa, Elenild; Sobel, Jeremy; Araujo, Wildo N.

    2009-01-01

    In 2006, a total of 178 cases of acute Chagas disease were reported from the Amazonian state of Pará, Brazil. Eleven occurred in Barcarena and were confirmed by visualization of parasites on blood smears. Using cohort and case–control studies, we implicated oral transmission by consumption of açaí palm fruit.

  5. ADENOSINE DEAMINASE ACTIVITY AND SERUM C-REACTIVE PROTEIN AS PROGNOSTIC MARKERS OF CHAGAS DISEASE SEVERITY

    Directory of Open Access Journals (Sweden)

    Iván Darío BRAVO-TOBAR

    2015-10-01

    Full Text Available SUMMARY Chagas disease is a public health problem worldwide. The availability of diagnostic tools to predict the development of chronic Chagas cardiomyopathy is crucial to reduce morbidity and mortality. Here we analyze the prognostic value of adenosine deaminase serum activity (ADA and C-reactive protein serum levels (CRP in chagasic individuals. One hundred and ten individuals, 28 healthy and 82 chagasic patients were divided according to disease severity in phase I (n = 35, II (n = 29, and III (n = 18. A complete medical history, 12-lead electrocardiogram, chest X-ray, and M-mode echocardiogram were performed on each individual. Diagnosis of Chagas disease was confirmed by ELISA and MABA using recombinant antigens; ADA was determined spectrophotometrically and CRP by ELISA. The results have shown that CRP and ADA increased linearly in relation to disease phase, CRP being significantly higher in phase III and ADA at all phases. Also, CRP and ADA were positively correlated with echocardiographic parameters of cardiac remodeling and with electrocardiographic abnormalities, and negatively with ejection fraction. CRP and ADA were higher in patients with cardiothoracic index ≥ 50%, while ADA was higher in patients with ventricular repolarization disturbances. Finally, CRP was positively correlated with ADA. In conclusion, ADA and CRP are prognostic markers of cardiac dysfunction and remodeling in Chagas disease.

  6. Chronic phase of Chagas disease: why should it be treated? A comprehensive review

    Directory of Open Access Journals (Sweden)

    José Rodrigues Coura

    2011-09-01

    Full Text Available The pathogenesis and evolutive pattern of Chagas disease suggests that the chronic phase should be more widely treated in order to (i eliminate Trypanosoma cruzi and prevent new inflammatory foci and the extension of tissue lesions, (ii promote tissue regeneration to prevent fibrosis, (iii reverse existing fibrosis, (iv prevent cardiomyopathy, megaoesophagus and megacolon and (v reduce or eliminate cardiac block and arrhythmia. All cases of the indeterminate chronic form of Chagas disease without contraindications due to other concomitant diseases or pregnancy should be treated and not only cases involving children or recently infected cases. Patients with chronic Chagas cardiomyopathy grade II of the New York Heart Association classification should be treated with specific chemotherapy and grade III can be treated according to medical-patient decisions. We are proposing the following new strategies for chemotherapeutic treatment of the chronic phase of Chagas disease: (i repeated short-term treatments for 30 consecutive days and interval of 30-60 days for six months to one year and (ii combinations of drugs with different mechanisms of action, such as benznidazole + nifurtimox, benznidazole or nifurtimox + allopurinol or triazole antifungal agents, inhibition of sterol synthesis.

  7. PRISM: A DATA-DRIVEN PLATFORM FOR MONITORING MENTAL HEALTH.

    Science.gov (United States)

    Kamdar, Maulik R; Wu, Michelle J

    2016-01-01

    Neuropsychiatric disorders are the leading cause of disability worldwide and there is no gold standard currently available for the measurement of mental health. This issue is exacerbated by the fact that the information physicians use to diagnose these disorders is episodic and often subjective. Current methods to monitor mental health involve the use of subjective DSM-5 guidelines, and advances in EEG and video monitoring technologies have not been widely adopted due to invasiveness and inconvenience. Wearable technologies have surfaced as a ubiquitous and unobtrusive method for providing continuous, quantitative data about a patient. Here, we introduce PRISM-Passive, Real-time Information for Sensing Mental Health. This platform integrates motion, light and heart rate data from a smart watch application with user interactions and text entries from a web application. We have demonstrated a proof of concept by collecting preliminary data through a pilot study of 13 subjects. We have engineered appropriate features and applied both unsupervised and supervised learning to develop models that are predictive of user-reported ratings of their emotional state, demonstrating that the data has the potential to be useful for evaluating mental health. This platform could allow patients and clinicians to leverage continuous streams of passive data for early and accurate diagnosis as well as constant monitoring of patients suffering from mental disorders.

  8. PrismTech Data Distribution Service Java API Evaluation

    Science.gov (United States)

    Riggs, Cortney

    2008-01-01

    My internship duties with Launch Control Systems required me to start performance testing of an Object Management Group's (OMG) Data Distribution Service (DDS) specification implementation by PrismTech Limited through the Java programming language application programming interface (API). DDS is a networking middleware for Real-Time Data Distribution. The performance testing involves latency, redundant publishers, extended duration, redundant failover, and read performance. Time constraints allowed only for a data throughput test. I have designed the testing applications to perform all performance tests when time is allowed. Performance evaluation data such as megabits per second and central processing unit (CPU) time consumption were not easily attainable through the Java programming language; they required new methods and classes created in the test applications. Evaluation of this product showed the rate that data can be sent across the network. Performance rates are better on Linux platforms than AIX and Sun platforms. Compared to previous C++ programming language API, the performance evaluation also shows the language differences for the implementation. The Java API of the DDS has a lower throughput performance than the C++ API.

  9. Optical system design of the Dyson imaging spectrometer based on the Fery prism

    Science.gov (United States)

    Pei, Linlin; Xiangli, Bin; Lv, Qunbo; Shao, Xiaopeng

    2016-07-01

    Imaging spectrometer has obtained wide development since rich feature information can be obtained by it; now, we focus on its high spectral resolution and miniaturization. In this paper, we design the Dyson imaging spectrometer system based on Fery prism. The average spectral resolution is 4.3 nm and the structure of the total length is 229 mm. It is a small, high-spectrometer imaging system. The front and rear surface of the traditional prism are plane, but the surfaces of the Fery prism are spherical, which can provide some optical power to realize imaging function and produce the dispersion effect. The Fery prism does not need to be placed in the parallel optical path, which simplifies the collimator lens and the imaging lens and are necessary in the prism spectrometer, making it possible to obtain a compact spectrometer. Full-spectrum transmittance of the prism is up to 94 %. Compared to the convex grating, the energy efficiency is greatly improved, and the free spectral range is wider, and its dispersion will not bring higher-order spectral aliasing problem. The small high spectrometer only includes two components. Its spectral range is from 400 to 1000 nm, covering the near-ultraviolet to near-infrared. The various aberrations of the typical spectrum are corrected. The spectrometer is excellent in performance.

  10. Optical system design of the Dyson imaging spectrometer based on the Fery prism

    Science.gov (United States)

    Pei, Linlin; Xiangli, Bin; Lv, Qunbo; Shao, Xiaopeng

    2016-08-01

    Imaging spectrometer has obtained wide development since rich feature information can be obtained by it; now, we focus on its high spectral resolution and miniaturization. In this paper, we design the Dyson imaging spectrometer system based on Fery prism. The average spectral resolution is 4.3 nm and the structure of the total length is 229 mm. It is a small, high-spectrometer imaging system. The front and rear surface of the traditional prism are plane, but the surfaces of the Fery prism are spherical, which can provide some optical power to realize imaging function and produce the dispersion effect. The Fery prism does not need to be placed in the parallel optical path, which simplifies the collimator lens and the imaging lens and are necessary in the prism spectrometer, making it possible to obtain a compact spectrometer. Full-spectrum transmittance of the prism is up to 94 %. Compared to the convex grating, the energy efficiency is greatly improved, and the free spectral range is wider, and its dispersion will not bring higher-order spectral aliasing problem. The small high spectrometer only includes two components. Its spectral range is from 400 to 1000 nm, covering the near-ultraviolet to near-infrared. The various aberrations of the typical spectrum are corrected. The spectrometer is excellent in performance.

  11. Multiplicity of carbohydrate-binding sites in -prism fold lectins: occurrence and possible evolutionary implications

    Indian Academy of Sciences (India)

    Alok Sharma; Divya Chandran; Desh D Singh; M Vijayan

    2007-09-01

    The -prism II fold lectins of known structure, all from monocots, invariably have three carbohydrate-binding sites in each subunit/domain. Until recently, -prism I fold lectins of known structure were all from dicots and they exhibited one carbohydrate-binding site per subunit/domain. However, the recently determined structure of the -prism fold I lectin from banana, a monocot, has two very similar carbohydrate-binding sites. This prompted a detailed analysis of all the sequences appropriate for two-lectin folds and which carry one or more relevant carbohydrate-binding motifs. The very recent observation of a -prism I fold lectin, griffithsin, with three binding sites in each domain further confirmed the need for such an analysis. The analysis demonstrates substantial diversity in the number of binding sites unrelated to the taxonomical position of the plant source. However, the number of binding sites and the symmetry within the sequence exhibit reasonable correlation. The distribution of the two families of -prism fold lectins among plants and the number of binding sites in them, appear to suggest that both of them arose through successive gene duplication, fusion and divergent evolution of the same primitive carbohydrate-binding motif involving a Greek key. Analysis with sequences in individual Greek keys as independent units lends further support to this conclusion. It would seem that the preponderance of three carbohydrate-binding sites per domain in monocot lectins, particularly those with the -prism II fold, is related to the role of plant lectins in defence.

  12. Rhomboid prism pair for rotating the plane of parallel light beams

    Science.gov (United States)

    Orloff, K. L. (Inventor); Yanagita, H.

    1982-01-01

    An optical system is described for rotating the plane defined by a pair of parallel light beams. In one embodiment a single pair of rhomboid prisms have their respective input faces disposed to receive the respective input beams. Each prism is rotated about an axis of revolution coaxial with each of the respective input beams by means of a suitable motor and gear arrangement to cause the plane of the parallel output beams to be rotated relative to the plane of the input beams. In a second embodiment, two pairs of rhomboid prisms are provided. In a first angular orientation of the output beams, the prisms merely decrease the lateral displacement of the output beams in order to keep in the same plane as the input beams. In a second angular orientation of the prisms, the input faces of the second pair of prisms are brought into coincidence with the input beams for rotating the plane of the output beams by a substantial angle such as 90 deg.

  13. Application of derivative matrices of skew rays to design of compound dispersion prisms.

    Science.gov (United States)

    Lin, Psang Dain

    2016-09-01

    Numerous optimization methods have been developed in recent decades for optical system design. However, these methods rely heavily on ray tracing and finite difference techniques to estimate the derivative matrices of the rays. Consequently, the accuracy of the results obtained from these methods is critically dependent on the incremental step size used in the tuning stage. To overcome this limitation, the present study proposes a comprehensive methodology for the design of compound dispersion prisms based on the first- and second-order derivative matrices of skew rays. The proposed method facilitates the analysis and design of prisms with respect to arbitrary system variables and provides an ideal basis for automatic prism design applications. Four illustrative examples are given. It is shown that the optical quantities required to evaluate the prism performance can be extracted directly from the proposed derivative matrices. In addition, it is shown in this study that the single-element 3D prism can have the same deviation angle and spectral dispersion as the 2D compound prism. PMID:27607509

  14. Assessment of Galectin-3 Polymorphism in Subjects with Chronic Chagas Disease

    Directory of Open Access Journals (Sweden)

    Gabriela da Silva Cruz

    2015-11-01

    Full Text Available AbstractBackground:Galectin-3, a β-galactoside binding lectin, has been described as a mediator of cardiac fibrosis in experimental studies and as a risk factor associated with cardiovascular events in subjects with heart failure. Previous studies have evaluated the genetic susceptibility to Chagas disease in humans, including the polymorphisms of cytokine genes, demonstrating correlations between the genetic polymorphism and cardiomyopathy development in the chronic phase. However, the relationship between the galectin-3 single nucleotide polymorphism (SNP and phenotypic variations in Chagas disease has not been evaluated.Objective:The present study aimed to determine whether genetic polymorphisms of galectin-3 may predispose to the development of cardiac forms of Chagas disease.Methods:Fifty-five subjects with Chagas disease were enrolled in this observational study. Real-time polymerase chain reaction (PCR was used for genotyping the variants rs4644 and rs4652 of the galectin-3 gene.Results:For the SNP rs4644, the relative risk for the cardiac form was not associated with the genotypes AA (OR = 0.79, p = 0.759, AC (OR = 4.38, p = 0.058, or CC (OR = 0.39, p = 0.127. Similarly, for the SNP rs4652, no association was found between the genotypes AA (OR = 0.64, p = 0.571, AC (OR = 2.85, p = 0.105, or CC (OR = 0.49, p = 0.227 and the cardiac form of the disease.Conclusion:Our results showed no association between the different genotypes for both SNPs of the galectin-3 gene and the cardiac form of Chagas disease. (Arq Bras Cardiol. 2015; [online].ahead print, PP.0-0

  15. In vitro and in vivo experimental models for drug screening and development for Chagas disease

    Directory of Open Access Journals (Sweden)

    Alvaro José Romanha

    2010-03-01

    Full Text Available Chagas disease, a neglected illness, affects nearly 12-14 million people in endemic areas of Latin America. Although the occurrence of acute cases sharply has declined due to Southern Cone Initiative efforts to control vector transmission, there still remain serious challenges, including the maintenance of sustainable public policies for Chagas disease control and the urgent need for better drugs to treat chagasic patients. Since the introduction of benznidazole and nifurtimox approximately 40 years ago, many natural and synthetic compounds have been assayed against Trypanosoma cruzi, yet only a few compounds have advanced to clinical trials. This reflects, at least in part, the lack of consensus regarding appropriate in vitro and in vivo screening protocols as well as the lack of biomarkers for treating parasitaemia. The development of more effective drugs requires (i the identification and validation of parasite targets, (ii compounds to be screened against the targets or the whole parasite and (iii a panel of minimum standardised procedures to advance leading compounds to clinical trials. This third aim was the topic of the workshop entitled Experimental Models in Drug Screening and Development for Chagas Disease, held in Rio de Janeiro, Brazil, on the 25th and 26th of November 2008 by the Fiocruz Program for Research and Technological Development on Chagas Disease and Drugs for Neglected Diseases Initiative. During the meeting, the minimum steps, requirements and decision gates for the determination of the efficacy of novel drugs for T. cruzi control were evaluated by interdisciplinary experts and an in vitro and in vivo flowchart was designed to serve as a general and standardised protocol for screening potential drugs for the treatment of Chagas disease.

  16. Prevalência da doença de Chagas em gestantes da região sul do Rio Grande do Sul Prevalence of Chagas disease among pregnant women in the southern region of Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Anelise Bergmann Araújo

    2009-12-01

    Full Text Available Anticorpos antiTrypanosoma cruzi no cordão umbilical de 351 parturientes da Cidade de Pelotas, RS foram pesquisados a fim de investigar a prevalência da doença de Chagas em gestantes. Um (0,3% caso foi identificado, não sendo detectada transmissão congênita. Salienta-se a importância da investigação da doença de Chagas em gestantes de zonas endêmicas ou provenientes destas.Anti-Trypanosoma cruzi antibodies in the umbilical cord of 351 parturients in the city of Pelotas, Rio Grande do Sul were investigated to determine the prevalence of Chagas disease among pregnant women. One case was identified (0.3%, without detection of congenital transmission. This highlights the importance of investigating Chagas disease among pregnant women living in or originating from endemic areas.

  17. Aspectos neurológicos da doença de chagas: sistema nervoso central Neurological aspects of Chagas' disease: central nervous system

    Directory of Open Access Journals (Sweden)

    Sylvio de Vergueiro Forjaz

    1967-09-01

    Full Text Available The lesions of the nervous system in the Trypanosomiasis Cruzi are quite frequent and are not only limited to the encephalo-spinal-axis. Actually, they are much more common in the peripheral representations of the autonomic nervous system, resulting in the so-called enteromegalies (mega-esophagus, megacolon, etc. so frequent in Brazil. However, only the clinical manifestations due to the encephalic and spinal lesions have been included in the neurological aspects of Chagas' disease (as formerly contended for by Carlos Chagas. In the acute phase of the central nervous system infestation, the Trypanosoma cruzi,as leishmanias, is found in cellular elements of the neuroglia (microglia, astroglia and may be isolated from the peripheral blood and cerebrospinal fluid (inoculation in sensitive animals. The corresponding clinical manifestations are the severe difuse meningo-encephalo-myelitis with a high degree of lethality and also signs of infection, hepatomegaly and splenomegaly. The infants from endemic areas are much more compromised. The clinical-pathologic as well as experimental confirmations on that acute phase of the disease are numerous and irrefutable. In the chronic phase of the disease, the neurological manifestations are not very clear. Early in 1909, Chagas, impressed with the great number of cases of infantile encephalopathy found in infested regions, imputed to the T. cruzithe etiology of such cases of encephalopathy and considered them as pertaining to a chronic phase of the disease. This has not been confirmed by other investigations, and even if the etiologic agent were the T. cruzithe clinical manifestations have no evolutive character and seem more sequelae than symptoms of a real chronic nervous phase. Even experimentally it has not been possible to demonstrate the presence of parasites in the nervous system of infested animals after clearing of the signs of the acute phase. In patients with chronic Chagas' disease with lesions in

  18. [Investigation of vectors and reservoirs in an acute Chagas outbreak due to possible oral transmission in Aguachica, Cesar, Colombia].

    Science.gov (United States)

    Soto, Hugo; Tibaduiza, Tania; Montilla, Marleny; Triana, Omar; Suárez, Diana Carolina; Torres Torres, Mariela; Arias, María Teresa; Lugo, Ligia

    2014-04-01

    Colombia recorded 11 cases of acute Chagas disease and 80 cases of oral contamination with Trypanosoma cruzi. The current study analyzes the entomological and parasitological characteristics of the outbreak in Aguachica, Cesar Department, in 2010. An interdisciplinary group of health professionals and regional university personnel conducted the laboratory tests in the patients and the investigation of the transmission focus. Eleven cases of acute Chagas diseases were detected in a single family in a dwelling with domiciliated triatomines and Rhodnius pallescens, Pantrongylus geniculatus, Eratyrus cuspidatus, and two Didelphis marsupialis opossums infected with T. cruzi in Attalea butyracea and Elaeis oleifera palm trees in the urban area of Aguachica. The study analyzes the role of R. pallescens and palm trees in the wild cycle of T. cruzi and in oral transmission of Chagas disease. Sporadic incursions by wild R. pallescens, P. geniculatus, and E. cuspidatus from the nearby palm trees into human dwellings may cause increasingly frequent outbreaks of oral Chagas disease. PMID:24896050

  19. [Investigation of vectors and reservoirs in an acute Chagas outbreak due to possible oral transmission in Aguachica, Cesar, Colombia].

    Science.gov (United States)

    Soto, Hugo; Tibaduiza, Tania; Montilla, Marleny; Triana, Omar; Suárez, Diana Carolina; Torres Torres, Mariela; Arias, María Teresa; Lugo, Ligia

    2014-04-01

    Colombia recorded 11 cases of acute Chagas disease and 80 cases of oral contamination with Trypanosoma cruzi. The current study analyzes the entomological and parasitological characteristics of the outbreak in Aguachica, Cesar Department, in 2010. An interdisciplinary group of health professionals and regional university personnel conducted the laboratory tests in the patients and the investigation of the transmission focus. Eleven cases of acute Chagas diseases were detected in a single family in a dwelling with domiciliated triatomines and Rhodnius pallescens, Pantrongylus geniculatus, Eratyrus cuspidatus, and two Didelphis marsupialis opossums infected with T. cruzi in Attalea butyracea and Elaeis oleifera palm trees in the urban area of Aguachica. The study analyzes the role of R. pallescens and palm trees in the wild cycle of T. cruzi and in oral transmission of Chagas disease. Sporadic incursions by wild R. pallescens, P. geniculatus, and E. cuspidatus from the nearby palm trees into human dwellings may cause increasingly frequent outbreaks of oral Chagas disease.

  20. Geochemistry of mud volcano fluids in the Taiwan accretionary prism

    Energy Technology Data Exchange (ETDEWEB)

    You Chenfeng; Gieskes, Joris M.; Lee, Typhoon; Yui Tzenfu; Chen Hsinwen

    2004-05-01

    Taiwan is located at the collision boundary between the Philippine Sea Plate and the Asian Continental Plate and is one of the most active orogenic belts in the world. Fluids sampled from 9 sub-aerial mud volcanoes distributed along two major geological structures in southwestern Taiwan, the Chishan fault and the Gutingkeng anticline, were analyzed to evaluate possible sources of water and the degree of fluid-sediment interaction at depth in an accretionary prism. Overall, the Taiwanese mud volcano fluids are characterized by high Cl contents, up to 347 mM, suggesting a marine origin from actively de-watering sedimentary pore waters along major structures on land. The fluids obtained from the Gutingkeng anticline, as well as from the Coastal Plain area, show high Cl, Na, K, Ca, Mg and NH{sub 4}, but low SO{sub 4} and B concentrations. In contrast, the Chishan fault fluids are much less saline (1/4 seawater value), but show much heavier O isotope compositions ({delta}{sup 18}O=5.1-6.5 %o). A simplified scenario of mixing between sedimentary pore fluids and waters affected by clay dehydration released at depth can explain several crucial observations including heavy O isotopes, radiogenic Sr contents ({sup 87}Sr/{sup 86}Sr=0.71136-0.71283), and relatively low salinities in the Chishan fluids. Gases isolated from the mud volcanoes are predominantly CH{sub 4} and CO{sub 2}, where the CH{sub 4}-C isotopic compositions show a thermogenic component of {delta}{sup 13}C=-38 %o. These results demonstrate that active mud volcano de-watering in Taiwan is a direct product of intense sediment accretion and plate collision in the region.

  1. Extended-Range Ultrarefractive 1D Photonic Crystal Prisms

    Science.gov (United States)

    Ting, David Z.

    2007-01-01

    by use of conventional prisms and diffraction gratings and is highly nonlinear.

  2. MORTALITY RISK ASSESSMENT IN PICU USING PRISM-III-24 SCORE

    Directory of Open Access Journals (Sweden)

    Harilal Naik

    2014-11-01

    Full Text Available OBJECTIVE: Assessment of risk of mortality using PRISM III-24 score in children admitted to PICU of Basaweshwara Teaching and General Hospital, attached to Mahadevappa Rampure Medical College, Gulbarga. DESIGN: Prospective cohort study. Setting: PICU of BTGH, Gulbarga. METHODS: 404 patients who had been admitted consecutively to the PICU during a period of 12 months (July 2011 to June 2012 were studied. PRISM III-24 score was calculated. Hospital outcome was recorded as survived/expired. Calibration and discrimination of the model was calculated by Hosmer-Lemeshow goodness-of-fit test and Area under the ROC Curve. The association between r (empirical function and PRISM III-24 score was assessed by Binary Logistic Regression method. RESULTS: Out of 404 patients, 363 (89.85% survived and 41 (10.15% expired. Males formed the majority (227/404. CNS cases (n=118, 29.2% constituted the majority. Mean age, length of hospitalization, and mean PRISM III-24 score were 59.22±51.12 months, 99.84±91.61 hours, and 4.92±7.74 (range 0-36. The test was well designed for the study (goodness-of-fit value P-value 0.186. ROC analysis indicated a strong predictive power for the PRISM III-24 (AUC 0.936. The observed (O mortality rate was 10.15% and the expected (E mortality rate was 10.12% with an O/E ratio of 1.003. CONCLUSION: PRISM III-24 score is a good predictor of mortality in PICU patients under Indian circumstances. The PRISM III-24 scoring system was highly calibrated in our institute.

  3. XeCl excimer laser with new prism resonator configurations and its performance characteristics

    International Nuclear Information System (INIS)

    New resonator cavity configurations, namely, the prism resonator and unstable prism resonator, are demonstrated for the first time in an excimer (XeCl) laser with interesting and novel results. High misalignment tolerance ∼50 mrad is achieved with considerably reduced beam divergence of less than ∼1 mrad without reduction in output power capabilities of the laser. The misalignment tolerance of ∼50 mrad is a dramatic improvement of ∼25 times compared to ∼2 mrad normally observed in standard excimer laser with plane-plane cavity. Increase in depth of focus from 3 mm to 5.5 mm was also achieved in case of prism resonator configuration with an improvement of about 60%. Unstable prism resonator configuration is demonstrated here in this paper with further reduction in beam divergence to about 0.5 mrad using plano-convex lens as output coupler. The misalignment tolerance in case of unstable prism resonator was retained at about 30 mrad which is a high value compared to standard unstable resonators. The output beam spot was completely filled with flat-top profile with prism resonator configurations, which is desired for various material processing applications. Focusing properties and beam divergence in case of prism resonator have been investigated using SEM (scanning electron microscope) images. SEM images of the focused spot size (∼20 μm holes) on metal sheet indicate beam divergence of about 0.05 mrad which is about 1.5 times diffraction limit. Energy contained in this angle is thus sufficient for micro-machining applications. Clean and sharp edges of the micro-holes show high pointing stability with multiple shot exposures. Such characteristics of the excimer laser system will be extremely useful in micro-machining and other field applications

  4. Formas encefalopaticas de enfermedad de Chagas cronica observadas en Argentina Encephalopathic form of chronic Chagas' disease observed in Argentine

    Directory of Open Access Journals (Sweden)

    Miguel Eduardo Jorg

    1981-12-01

    Full Text Available Se describen las características clínicas y las manifestaciones dominantes en 22 enfermos observados entre 1963 y 1978 sobre un total de 420 con neuropatías diversas examinados en el area central Norte de la Argentina; afectados por una encefalopatía crónica, que, por hallazgos de laboratorio (demostración del parasito en sangre o en su defecto confirmacion por mas de una prueba serológica positiva y por las correlaciones anatomoclínicas, puede ser imputada a la infección por el Trypanosoma cruzi. En la mitad o mas de los enfermos, son salientes las siguientes manifestaciones: disprosexia y confusión en 81,8%; cefalea y confusión en 72,7%; debilitamiento de reflejos músculo-tendinosos y trastornos del lenguaje en 63,6%; dispraxias en 59%; trastornos de la marcha y crisis mioclónicas en 54,5%; bradicinesias en 50%. En menor escala se encontraron: parestesias, ideas delirantes, perturbaciones cerebelares, crisis de vertigo, diplopia, lipotimias,humor fluctuante. Las menos frecuentes: disautonomia y excitacion. En 8 se hallaron evidencias semiologicas de cardiopatias y en 2 de compromiso digestivo grosero. Se analiza el alcance de esta casuistica en relación a los hallazgos anatomopatológicos en casos mortales y con referencia a lo ya conocido sobre la forma neuropatologica de la enfermedad de Chagas cronica.Among 420 patientes found with diverse subacute and chronic neuropathies, 22 were diagnosed as cases of true trypanosomic encephalopathy by means of the demonstration of parasites in blood (by xenodiagnosis or hemoculture or through serologic tests. In 50% or more of those patientes, following semiologic elements were prevalente: dysprosexia and depression in 81.8%; cephalea and confusion in 72.7%; weakness of muscular-tendineous reflexes and speech disturbance in 63.6% dispraxies in 59.0%; disturbances of gait and myoclonic crises in 54.5%; bradikinesias in 59.0%. Other symptoms were verified in a mirror scale: paresias

  5. Synthesis of hexagonal wurtzite Cu2ZnSnS4 prisms by an ultrasound-assisted microwave solvothermal method

    Science.gov (United States)

    Long, Fei; Chi, Shangsen; He, Jinyun; Wang, Jilin; Wu, Xiaoli; Mo, Shuyi; Zou, Zhengguang

    2015-09-01

    Wurtzite Cu2ZnSnS4 (CZTS) hexagonal prisms were synthesized by a simple ultrasound-microwave solvothermal method. The product was characterized by XRD, FESEM, EDS, TEM, Raman and UV-vis spectrometer. The hexagonal prisms were 0.5-2 μm wide and 5-12 μm long. The PVP played an important role in the formation of the CZTS hexagonal prisms. In addition, the ultrasound-assisted microwave process was helpful for synthesis of wurtzite rather than kesterite phase CZTS. A nucleation-dissolution-recrystallization mechanism was also proposed to explain the growth of the CZTS hexagonal prisms.

  6. Assessment and epidemiology of Chagas' disease in patients treated in Araguaina - Tocantins

    International Nuclear Information System (INIS)

    Chagas disease (AD) was described by Carlos Chagas in 1909. It is caused by a parasite T. cruzi, transmitted by bugs, by blood transfusion, vertical and orally. The DC has two phases: acute and chronic. The evolution to the cardiac form occurs in about 30% of chronic cases and is the largest cause of mortality in chronic Chagas disease. The aim of this study was to Chagas' disease in patients of Tocantins, compared with other heart patients and asymptomatic from the standpoint of non-invasive exams using radiant energies such as echocardiography and ECG and RX. The descriptive study included 80 patients, 20 chronic form of Chagas disease, 20 indeterminate, 20 with other heart diseases, and 20 controls. There was a prevalence of 9.5% of chagasic patients treated in outpatient cardiology at Araguaina Tocantins, and 7.3% in chronic and 2.21% in the indeterminate. Of the chronic patients in the study 50% had mega esophagus and megacolon 4 (20%). Most patients had no family history of AD, nor was a smoker or drinker. Major electrocardiographic abnormalities found refer to driving. The evaluation of ICT, the chronic chagasic showed that increased by 40% of patients, 40% had esophageal changes and 20% of patients had megacolon s. The echocardiogram was abnormal in 42%). 27% of patients had EF below 55% changed. Changes in segmental contractility and Asynchrony septum were found in 80% of chronic Chagas disease. In 80% of the patients was observed diastolic dysfunction. The valvular changes occurred in 75%. Electrocardiographic abnormalities occurred in 80% of patients with CCC, while the other heart had ECG changes. Arterial hypertension had an incidence of 45% in patients with CCC and 40% in FCI. The systolic and diastolic ventricular dysfunction was more prevalent in groups that had an abnormal ECG and arrhythmia. Observed that the group of chagasic decreased ejection fraction is correlated to a higher incidence of arrhythmias besides diastolic dysfunction and related

  7. Investigation of beam steering performances in rotation Risley-prism scanner.

    Science.gov (United States)

    Li, Anhu; Sun, Wansong; Yi, Wanli; Zuo, Qiyou

    2016-06-13

    Rotation Risley-prism scanner appears to be the most promising solution to high-accuracy beam scanning and target tracking. In the paper, some important issues crucial to the function implementation are thoroughly investigated. First the forming law of scan blind zone relative to double-prism structural parameters is explored by a quantitative analysis method. Then the nonlinear relationship between the rotation speeds of double prisms and the change rate of beam deviation angle is presented, and the beam scan singularity is indicated as an essential factor that confines the beam scan region. Finally, the high-accuracy radial scan theory is verified to illustrate the important application owing to the high reduction ratio from the rotation angles of double prisms to the deviation angles of the emergent beam. The research not only reveals the inner mechanisms of the Risley-prism beam scanning in principle, but also provide a foundation for the nonlinear control of various beam scan modes. PMID:27410303

  8. Accelerator system for the PRISM based muon to electron conversion experiment

    CERN Document Server

    Alekou, A; Aslaninejad, M; Barlow, R J; Hock, R Chudzinski K M; Garland, J; Jenner, L J; Kelliher, D J; Kuno, Y; Kurup, A; Lagrange, J-B; Lancaster, M; Machida, S; Mori, Y; Muratori, B; Ohmori, C; Owen, H; Pasternak, J; Planche, T; Prior, C; Sato, A; Shi, Y; Smith, S; Uchida, Y; Witte, H; Yokoi, T; C13-07-29.2

    2013-01-01

    The next generation of lepton flavor violation experiments need high intensity and high quality muon beams. Production of such beams requires sending a short, high intensity proton pulse to the pion production target, capturing pions and collecting the resulting muons in the large acceptance transport system. The substantial increase of beam quality can be obtained by applying the RF phase rotation on the muon beam in the dedicated FFAG ring, which was proposed for the PRISM project.This allows to reduce the momentum spread of the beam and to purify from the unwanted components like pions or secondary protons. A PRISM Task Force is addressing the accelerator and detector issues that need to be solved in order to realize the PRISM experiment. The parameters of the required proton beam, the principles of the PRISM experiment and the baseline FFAG design are introduced. The spectrum of alternative designs for the PRISM FFAG ring are shown. Progress on ring main systems like injection and RF are presented. The cu...

  9. All-prism achromatic phase matching for tunable second-harmonic generation.

    Science.gov (United States)

    Richman, B A; Bisson, S E; Trebino, R; Sidick, E; Jacobson, A

    1999-05-20

    Achromatic phase matching (APM) involves dispersing the light entering a nonlinear optical crystal so that a wide range of wavelengths is simultaneously phase matched. We constructed an APM apparatus consisting of six prisms, the final dispersion angle of which was optimized to match to second order in wavelength the type I phase-matching angle of beta barium borate (BBO). With this apparatus, we doubled tunable fundamental light from 620 to 700 nm in wavelength using a 4-mm-long BBO crystal. An analogous set of six prisms after the BBO crystal, optimized to second order in second-harmonic wavelength, realigned the output second-harmonic beams. Computer simulations predict that adjustment of a single prism can compensate angular misalignment of any or all the prisms before the crystal, and similarly for the prisms after the crystal. We demonstrated such compensation with the experimental device. The simulations also indicate that the phase-matching wavelength band can be shifted and optimized for different crystal lengths.

  10. Fusional Vergence Detected by Prism Bar and Synoptophore in Chinese Childhood Intermittent Exotropia

    Directory of Open Access Journals (Sweden)

    Tao Fu

    2015-01-01

    Full Text Available Purpose. To measure the changes in fusional vergence in Chinese children with intermittent exotropia (IXT and the association with the control of IXT. Methods. Ninety-two patients with IXT (8–15 years old were compared with 86 controls. Exodeviation control was evaluated using the Revised Newcastle Control Score. Angle of deviation was measured using prism and alternate cover testing at distance and near. Fusional vergence was measured using prism bar and synoptophore. This study was registered with ChiCTR-RCC-13003920. Results. Using prism bar, convergence break points were lower whereas divergence break points were higher in children with IXT at distance (P<0.001 and near (P<0.001 compared with controls. There was no significant difference in mean divergence amplitudes between the two groups when testing using a synoptophore (P=0.53. In children with IXT, the distance between recovery point and break point in both convergence (distance: P=0.02; near: P=0.02 and divergence (distance: P<0.001; near: P<0.001 was larger than controls when detected by prism bar and synoptophore (convergence: P=0.005; divergence: P=0.006. Conclusions. Children with IXT have reduced convergence amplitudes as detected by both prism bar and synoptophore.

  11. DSM Generation from ALSO/PRISM Images Using SAT-PP

    Science.gov (United States)

    Wolff, Kirsten; Gruen, Armin

    2008-11-01

    One of the most important products of ALOS/PRISM image data are accurate DSMs. To exploit the full potential of the full resolution of PRISM for DSM generation, a highly developed image matcher is needed. As a member of the validation and calibration team for PRISM we published earlier results of DSM generation using PRISM image triplets in combination with our software package SAT-PP. The overall accuracy across all object and image features for all tests lies between 1-5 pixels in matching, depending primarily on surface roughness, vegetation, image texture and image quality. Here we will discuss some new results. We focus on four different topics: the use of two different evaluation methods, the difference between a 5m and a 10m GSD for the final PRISM DSM, the influence of the level of initial information and the comparison of the quality of different combinations of the three different views forward, nadir and backward. All tests have been conducted with our testfield Bern/Thun, Switzerland.

  12. THREE-DIMENSIONAL IGNITION AND GROWTH REACTIVE FLOW MODELING OF PRISM FAILURE TESTS ON PBX 9502

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M L; Tarver, C M

    2006-06-20

    The Ignition and Growth reactive flow model for shock initiation and detonation of solid explosives based on triaminotirnitrobenzene (TATB) is applied to three-dimensional detonation wave propagation. The most comprehensive set of three-dimensional detonation wave propagation data is that measured using the trapezoidal prism test. In this test, a PBX 9501 (95% HMX, 2.5% Estane, and 2.5% BDNPA/F) line detonator initiates a detonation wave along the trapezoidal face of a PBX 9502 (95% TATB and 5% Kel-F binder) prism. The failure thickness, which has been shown experimentally to be roughly half of the failure diameter of a long cylindrical charge, is measured after 50 mm of detonation wave propagation by impact with an aluminum witness plate. The effects of confinement impedance on the PBX 9502 failure thickness have been measured using air (unconfined), water, PMMA, magnesium, aluminum, lead, and copper placed in contact with the rectangular faces of the prism parallel to the direction of detonation propagation. These prism test results are modeled using the two-dimensional PBX 9502 Ignition and Growth model parameters determined by calculating failure diameter and tested on recent corner turning experiments. Good agreement between experimentally measured and calculated prism failure thicknesses for unconfined and confined PBX 9502 is reported.

  13. Prism-patterned Nafion membrane for enhanced water transport in polymer electrolyte membrane fuel cell

    Science.gov (United States)

    Kim, Sang Moon; Kang, Yun Sik; Ahn, Chiyeong; Jang, Segeun; Kim, Minhyoung; Sung, Yung-Eun; Yoo, Sung Jong; Choi, Mansoo

    2016-06-01

    Here, we report a simple and effective strategy to enhance the performance of the polymer electrolyte membrane fuel cell by imprinting prism-patterned arrays onto the Nafion membrane, which provides three combined effects directly related to the device performance. First, a locally thinned membrane via imprinted micro prism-structures lead to reduced membrane resistance, which is confirmed by electrochemical impedance spectroscopy. Second, increments of the geometrical surface area of the prism-patterned Nafion membrane compared to a flat membrane result in the increase in the electrochemical active surface area. Third, the vertically asymmetric geometry of prism structures in the cathode catalyst layer lead to enhanced water transport, which is confirmed by oxygen gain calculation. To explain the enhanced water transport, we propose a simple theoretical model on removal of water droplets existing in the asymmetric catalyst layer. These three combined effects achieved via incorporating prism patterned arrays into the Nafion membrane effectively enhance the performance of the polymer electrolyte membrane fuel cell.

  14. All-prism achromatic phase matching for tunable second-harmonic generation.

    Science.gov (United States)

    Richman, B A; Bisson, S E; Trebino, R; Sidick, E; Jacobson, A

    1999-05-20

    Achromatic phase matching (APM) involves dispersing the light entering a nonlinear optical crystal so that a wide range of wavelengths is simultaneously phase matched. We constructed an APM apparatus consisting of six prisms, the final dispersion angle of which was optimized to match to second order in wavelength the type I phase-matching angle of beta barium borate (BBO). With this apparatus, we doubled tunable fundamental light from 620 to 700 nm in wavelength using a 4-mm-long BBO crystal. An analogous set of six prisms after the BBO crystal, optimized to second order in second-harmonic wavelength, realigned the output second-harmonic beams. Computer simulations predict that adjustment of a single prism can compensate angular misalignment of any or all the prisms before the crystal, and similarly for the prisms after the crystal. We demonstrated such compensation with the experimental device. The simulations also indicate that the phase-matching wavelength band can be shifted and optimized for different crystal lengths. PMID:18319927

  15. Beyond the sensorimotor plasticity: cognitive expansion of prism adaptation in healthy individuals.

    Directory of Open Access Journals (Sweden)

    Carine eMICHEL

    2016-01-01

    Full Text Available Sensorimotor plasticity allows us to maintain an efficient motor behavior in reaction to environmental changes. One of the classical models for the study of sensorimotor plasticity is prism adaptation. It consists of pointing to visual targets while wearing prismatic lenses that shift the visual field laterally. The conditions of the development of the plasticity and the sensorimotor after-effects have been extensively studied for more than a century. However, the interest taken in this phenomenon was considerably increased since the demonstration of neglect rehabilitation following prism adaptation by Rossetti and his colleagues in 1998. Mirror effects, i.e. simulation of neglect in healthy individuals, were observed for the first time by Colent and collaborators in 2000. The present review focuses on the expansion of prism adaptation to cognitive functions in healthy individuals during the last 15 years. Cognitive after-effects have been shown in numerous tasks even in those that are not intrinsically spatial in nature. Altogether, these results suggest the existence of a strong link between low-level sensorimotor plasticity and high-level cognitive functions and raise important questions about the mechanisms involved in producing unexpected cognitive effects following prism adaptation. Implications for the functional mechanisms and neuroanatomical network of prism adaptation are discussed to explain how sensorimotor plasticity may affect cognitive processes.

  16. Seroepidemiological and clinical study of Chagas' disease in Nicaragua Estudio seroepidemiológico y clínico de la enfermedad de Chagas en Nicaragua

    Directory of Open Access Journals (Sweden)

    Teresa Rivera B

    1995-06-01

    Full Text Available With the aim of determining the prevalence, immunological profile, and knowing the electrocardiographic alterations, a clinical and Seroepidemiological study of Chagas' disease was performed in three rural settlements located at the North, East and West of Nicaragua. Anti T. cruzi antibodies were searched by indirect immunofluorescence (IFI and hemagglutination (IHA in a total of 803 subjects. Seropositives and the same number of seronegatives, matched by age and sex, were included in a case-control design for the electrocardiographic assessment. Antibody prevalence was 13.1, 4.3 and 3.2% in the respective settlements. In the first two the immunological profile corresponds to that of an endemic zone of long standing, were transmission has decreased, and in the third the pattern is of a zone under control. Electrocardiographic changes compatible with Chagas' disease were found in seropositive individuals, but difference with control group was not statistically significant. It is concluded that the disease is endemic in the three settlements and the clinical aspect requires further evaluation, including additional cardiologic techniques.Con el objetivo de determinar la prevalencia, perfil inmunológico de la población y conocer las alteraciones electrocardiográficas; se realizó un estudio seroepidemiológico y clínico de la enfermedad de Chagas en tres localidades ubicadas al Norte, Oriente y Occidente de Nicaragua. Como muestra se tomó suero a 803 personas, a las que se les realizó busqueda de anticuerpos anti T. cruzi por Inmunofluorescencia (IFI y Hemaglutinación Indirecta (HAI. Al total de los pacientes de dos de éstas localidades que resultaron con serología positiva, se les evaluó por electrocardiografía, estableciendo un grupo control con seronegativos con las mismas características de edad y sexo. La prevalencia de anticuerpos fué de 13.1, 4.3, y 3.2% en las tres localidades respectivamente. En las dos primeras el perfil

  17. Chagas' disease in the Brazilian Amazon: I - a short review Doença de Chagas na Amazônia Brasileira: I. revisão

    Directory of Open Access Journals (Sweden)

    José Rodrigues Coura

    1994-08-01

    Full Text Available At least eighteen species of triatominae have been found in the Brazilian Amazon, nine of them naturally infected with Trypanosoma cruzi or "cruzi-like" trypanosomes and associated with numerous wild reservoirs. Despite the small number of human cases of Chagas' disease described to date in the Brazilian Amazon the risk that the disease will become endemic in this area is increasing for the following reasons: a uncontrolled deforestation and colonization altering the ecological balance between reservoir hosts and wild vectors; b the adaptation of reservoir hosts of T.cruzi and wild vectors to peripheral and intradomiciliary areas, as the sole feeding alternative; c migration of infected human population from endemic areas, accompanied by domestic reservoir hosts (dogs and cats or accidentally carrying in their baggage vectors already adapted to the domestic habitat. In short, risks that Chagas' disease will become endemic to the Amazon appear to be linked to the transposition of the wild cycle to the domestic cycle in that area or to transfer of the domestic cycle from endemic areas to the Amazon.Pelo menos dezoito espécies de triatomíneos foram encontradas na Amazônia brasileira, nove das quais infectadas com Trypanosoma cruzi ou semelhante ("cruzi-like", associadas com numerosos reservatórios silvestres. A despeito do pequeno número de casos humanos da doença de Chagas descritos até agora na Amazônia brasileira, o risco que essa doença se torne endêmica é cada vez maior, pelas seguintes razões: a desmatamentos e colonização descontrolados, alterando o balanço entre reservatórios e vetores; b adaptação de reservatórios e vetores silvestres com T.cruzi ao peridomicílio, como única alternativa alimentar; c migração de populações humanas infectadas com T.cruzi acompanhadas de reservatórios domésticos (cães e gatos ou de vetores de suas regiões de origem na bagagem, já adaptados ao domicílio. Em resumo, o risco de que

  18. Outbreak of acute Chagas disease associated with oral transmission in the Rio Negro region, Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Rita de Cássia de Souza-Lima

    2013-10-01

    Full Text Available Introduction Chagas disease is considered as emerging in the Brazilian Amazon, usually occurring in acute outbreaks. Methods We describe 17 cases of acute Chagas disease in Rio Negro, Amazonas. Results There were 15 males (average age, 31.3 years, all positive for Trypanosoma cruzi in fresh blood smear examination, and 14 positive by xenodiagnosis and PCR. The top clinical manifestations were fever, asthenia, abdominal pain, and palpitations. Electrocardiograms featured low-voltage QRS, anterosuperior divisional block, and right bundle branch block associated with anterosuperior divisional block. Conclusions All patients had consumed açaí products from Monte Alegre in the rural area around Santa Izabel do Rio Negro, Brazil.

  19. Outbreak of acute Chagas disease associated with oral transmission in the Rio Negro region, Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Rita de Cassia de Souza-Lima

    2013-07-01

    Full Text Available Introduction Chagas disease is considered as emerging in the Brazilian Amazon, usually occurring in acute outbreaks. Methods We describe 17 cases of acute Chagas disease in Rio Negro, Amazonas. Results There were 15 males (average age, 31.3 years, all positive for Trypanosoma cruzi in fresh blood smear examination, and 14 positive by xenodiagnosis and PCR. The top clinical manifestations were fever, asthenia, abdominal pain, and palpitations. Electrocardiograms featured low-voltage QRS, anterosuperior divisional block, and right bundle branch block associated with anterosuperior divisional block. Conclusions All patients had consumed açaí products from Monte Alegre in the rural area around Santa Izabel do Rio Negro, Brazil.

  20. Estado actual de nuestros conocimientos sobre la enfermedad de chagas en la Republica Mexicana

    Directory of Open Access Journals (Sweden)

    Jorge Tay

    1981-06-01

    Full Text Available Se presentan los datos obtenidos de la revisión minuciosa en relación a enfermedad de Chagas de la literatura médica de la República Mexicana y extranjera desde el afio de 1939 en que por primeira vez se reporta a Trypanosoma cruzi en México, hasta el ano de 1976. Mediante mapas, tablas y cuadros se senalan las localidades en donde se han encontrado casos humanos, reservorios no humanos y transmisores. Se hacen comentários acerca de los resultados obtenidos y se seffala la importancia de incrementar los estúdios sobre enfermedades de Chagas en nuestro país.

  1. Chagas disease: from bush to huts and houses. Is it the case of the Brazilian amazon?

    Directory of Open Access Journals (Sweden)

    José Rodrigues Coura

    1999-09-01

    Full Text Available Two of the major problems facing the Amazon - human migration from the other areas and uncontrolled deforestation - constitute the greatest risk for the establishment of endemic Chagas disease in this part of Brazil. At least 18 species of triatomines had been found in the Brazilian Amazon, 10 of them infected with Trypanosoma cruzi, associated with numerous wild reservoirs. With wide-range deforestation, wild animals will perforce be driven into other areas, with tendency for triatomines to become adapted to alternative food sources in peri and intradomicilies. Serological surveys and cross-sectional studies for Chagas disease, carried out in rural areas of the Rio Negro, in the Brazilian Amazon, showed a high level of seropositivity for T. cruzi antibodies. A strong correlation of seroreactivity with the contact of gatherers of piaçava fibers with wild triatomines could be evidenced.

  2. A Case of Vertical Transmission of Chagas Disease Contracted via Blood Transfusion in Canada

    Directory of Open Access Journals (Sweden)

    Margaret A Fearon

    2013-01-01

    Full Text Available Chagas disease is caused by the protozoan parasite Trypanosoma cruzi and is endemic in many countries in Latin America, where infected bugs of the Triatominea subfamily carry the parasite in the gut and transmit it to humans through fecal contamination of a bite. However, vertical transmission and transmission through blood transfusion and organ transplantation is well documented. Increasing immigration from endemic countries to North America has prompted blood operators, including Canadian Blood Services and Hema Quebec, to initiate blood donor testing for Chagas antibody. In the present report, an unusual case of vertical transmission from a mother, most likely infected through blood transfusion, and detected as part of a concurrent seroprevalence study in blood donors is described.

  3. [Carlos Chagas Filho: an articulator of the history of sciences in Brazil].

    Science.gov (United States)

    Domingues, Heloisa Maria Bertol

    2012-06-01

    A letter sent in 1982 by a group of scientists to the president of Conselho Nacional de Desenvolvimento Científico e Tecnológico appealed for a policy of preservation of Brazilian scientific culture. The name of Carlos Chagas Filho topped the list of signatures thereby proving his commitment to that proposal, the ideological structure of which was part of his experience in scientific policy in Brazil and abroad. This document harks back to the practice of the history of the sciences in Brazil and the creation of places for the safeguard and organization of scientific memory, such as the Museu de Astronomia e Ciências Afins, Casa de Oswaldo Cruz and the Sociedade Brasileira de História da Ciência, of which Carlos Chagas Filho was an inaugural member of the board of directors.

  4. Interferon-γ and other inflammatory mediators in cardiomyocyte signaling during Chagas disease cardiomyopathy

    Institute of Scientific and Technical Information of China (English)

    Ludmila; Rodrigues; Pinto; Ferreira; Amanda; Farage; Frade; Monique; Andrade; Baron; Isabela; Cunha; Navarro; Jorge; Kalil; Christophe; Chevillard; Edecio; Cunha-Neto

    2014-01-01

    Chagas disease cardiomyopathy(CCC), the main consequence of Trypanosoma cruzi(T.cruzi) infection, is an inflammatory cardiomyopathy that develops in up to 30% of infected individuals. The heart inflammation in CCC patients is characterized by a Th1 T cell-rich myocarditis with increased production of interferon(IFN)-γ, produced by the CCC myocardial infiltrate and detected at high levels in the periphery. IFN-γ has a central role in the cardiomyocyte signaling during both acute and chronic phases of T.cruzi infection. In this review, we have chosen to focus in its pleiotropic mode of action during CCC, which may ultimately be the strongest driver towards pathological remodeling and heart failure. We describe here the antiparasitic protective and pathogenic dual role of IFN-γ in Chagas disease.

  5. Interferon-γ and other inflammatory mediators in cardiomyocyte signaling during Chagas disease cardiomyopathy.

    Science.gov (United States)

    Ferreira, Ludmila Rodrigues Pinto; Frade, Amanda Farage; Baron, Monique Andrade; Navarro, Isabela Cunha; Kalil, Jorge; Chevillard, Christophe; Cunha-Neto, Edecio

    2014-08-26

    Chagas disease cardiomyopathy (CCC), the main consequence of Trypanosoma cruzi (T.cruzi) infection, is an inflammatory cardiomyopathy that develops in up to 30% of infected individuals. The heart inflammation in CCC patients is characterized by a Th1 T cell-rich myocarditis with increased production of interferon (IFN)-γ, produced by the CCC myocardial infiltrate and detected at high levels in the periphery. IFN-γ has a central role in the cardiomyocyte signaling during both acute and chronic phases of T.cruzi infection. In this review, we have chosen to focus in its pleiotropic mode of action during CCC, which may ultimately be the strongest driver towards pathological remodeling and heart failure. We describe here the antiparasitic protective and pathogenic dual role of IFN-γ in Chagas disease. PMID:25228957

  6. Population differentiation of the Chagas disease vector Triatoma maculata (Erichson, 1848) from Colombia and Venezuela.

    Science.gov (United States)

    Monsalve, Yoman; Panzera, Francisco; Herrera, Leidi; Triana-Chávez, Omar; Gómez-Palacio, Andrés

    2016-06-01

    The emerging vector of Chagas disease, Triatoma maculata (Hemiptera, Reduviidae), is one of the most widely distributed Triatoma species in northern South America. Despite its increasing relevance as a vector, no consistent picture of the magnitude of genetic and phenetic diversity has yet been developed. Here, several populations of T. maculata from eleven Colombia and Venezuela localities were analyzed based on the morphometry of wings and the mitochondrial NADH dehydrogenase subunit 4 (ND4) gene sequences. Our results showed clear morphometric and genetic differences among Colombian and Venezuelan populations, indicating high intraspecific diversity. Inter-population divergence is suggested related to East Cordillera in Colombia. Analyses of other populations from Colombia, Venezuela, and Brazil from distinct eco-geographic regions are still needed to understand its systematics and phylogeography as well as its actual role as a vector of Chagas disease. PMID:27232127

  7. New approach towards the synthesis of selenosemicarbazones, useful compounds for Chagas' disease.

    Science.gov (United States)

    Pizzo, Chiara; Faral-Tello, Paula; Yaluff, Gloria; Serna, Elva; Torres, Susana; Vera, Ninfa; Saiz, Cecilia; Robello, Carlos; Mahler, Graciela

    2016-02-15

    Herein, we describe a new approach towards the synthesis of selenosemicarbazones. The reaction involves an O-Se exchange of semicarbazones using Ishihara reagent. Eleven selenosemicarbazones were prepared using this methodology, with low to moderate yields. Among the prepared compounds the m-bromo phenyl methyl derivative 1b was selected to be evaluated in vivo, in a murine model of acute Chagas' disease. Compound 1b 10 mg/kg bw/day reduced 50% of parasitaemia profile compared with the control group, but was less effective than Benznidazole (50 mg/kg bw/day reduced 90%) and toxic. These studies are important to guide future Chagas drug design. PMID:26774036

  8. Bragg prism monochromator and analyser for super ultra-small angle neutron scattering studies

    Indian Academy of Sciences (India)

    Apoorva G Wagh; Sohrab Abbas; Markus Strobl; Wolfgang Treimer

    2008-11-01

    We have designed, fabricated and operated a novel Bragg prism monochromator–analyser combination. With a judicious choice of the Bragg reflection, its asymmetry and the apex angle of the silicon single crystal prism, the monochromator has produced a neutron beam with sub-arcsec collimation. A Bragg prism analyser with the opposite asymmetry has been tailored to accept a still sharper angular profile. With this optimized monochromator–analyser pair, we have attained the narrowest and sharpest neutron angular profile to date. At this facility, we have recorded the first SUSANS spectra spanning wave vector transfers ∼ 10−6 Å-1 to characterize samples containing agglomerates up to tens of micrometres in size.

  9. Molten-salt Synthesis and Properties of ZnS with Hexagonal Prism Morphology

    Institute of Scientific and Technical Information of China (English)

    LIU, Jin-Song; JI, Guang-Bin; LI, Zi-Quan; CAO, Jie-Ming; ZHENG, Ming-Bo; KE, Xing-Fei

    2007-01-01

    ZnS with hexagonal prism morphology has been synthesized successfully by molten-salt method with ZnS nanoparticles as precursors, and the ZnS nanoparticles were prepared by one-step solid-state reaction of Zn(CH3COO)2·2H2O with Na2S·9H2O at ambient temperature. Crystal structure and morphology of the product were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and HRTEM. Ultraviolet-visible optical absorption spectrum of the ZnS hexagonal prism shows a distinct red shift from that of bulk ZnS crystals and photoluminescence spectrum exhibits strong emissions at 380 and 500 nm, respectively. Further experiments were designed and the formation mechanism of the ZnS hexagonal prism has been also discussed in brief.

  10. Os experimentos prismáticos de Goethe Goethe's prismatic experiments

    Directory of Open Access Journals (Sweden)

    Fred Jordan

    1993-12-01

    Full Text Available O ensaio pretende estimular a realização de experimentos prismáticos com recursos muito simples e, com isso, facilitar o acesso aos fundamentais estudos de Goethe sobre cor, a "Farbenlehre". O encarte anexo contém fotos de um processo prismático complementar, produzido por Imagens-Modelo em Claro-Escuro neutro. Contém ainda fotos de imagens prismáticas produzidas por Imagens-Modelo em cores.The essay intends to stimulate the carrying out of prismatic experiments with very simple resources and, therewith, ease the access to Goethe's fundamental color studies, the "Farbenlehre". The included folder contains photographs of a complementary prismatic process produced by neutral bright-dark Model-Images. It also contains photographs of prismatic images produced by colored Model-Images.

  11. Laser Oscillator Incorporating a Wedged Polarization Rotator and a Porro Prism as Cavity Mirror

    Science.gov (United States)

    Li, Steven

    2011-01-01

    A laser cavity was designed and implemented by using a wedged polarization rotator and a Porro prism in order to reduce the parts count, and to improve the laser reliability. In this invention, a z-cut quartz polarization rotator is used to compensate the wavelength retardance introduced by the Porro prism. The polarization rotator rotates the polarization of the linear polarized beam with a designed angle that is independent of the orientation of the rotator. This unique property was used to combine the retardance compensation and a Risley prism to a single optical component: a wedged polarization rotator. This greatly simplifies the laser alignment procedure and reduces the number of the laser optical components.

  12. Lower richness of small wild mammal species and chagas disease risk.

    Directory of Open Access Journals (Sweden)

    Samanta Cristina das Chagas Xavier

    Full Text Available A new epidemiological scenario involving the oral transmission of Chagas disease, mainly in the Amazon basin, requires innovative control measures. Geospatial analyses of the Trypanosoma cruzi transmission cycle in the wild mammals have been scarce. We applied interpolation and map algebra methods to evaluate mammalian fauna variables related to small wild mammals and the T. cruzi infection pattern in dogs to identify hotspot areas of transmission. We also evaluated the use of dogs as sentinels of epidemiological risk of Chagas disease. Dogs (n = 649 were examined by two parasitological and three distinct serological assays. kDNA amplification was performed in patent infections, although the infection was mainly sub-patent in dogs. The distribution of T. cruzi infection in dogs was not homogeneous, ranging from 11-89% in different localities. The interpolation method and map algebra were employed to test the associations between the lower richness in mammal species and the risk of exposure of dogs to T. cruzi infection. Geospatial analysis indicated that the reduction of the mammal fauna (richness and abundance was associated with higher parasitemia in small wild mammals and higher exposure of dogs to infection. A Generalized Linear Model (GLM demonstrated that species richness and positive hemocultures in wild mammals were associated with T. cruzi infection in dogs. Domestic canine infection rates differed significantly between areas with and without Chagas disease outbreaks (Chi-squared test. Geospatial analysis by interpolation and map algebra methods proved to be a powerful tool in the evaluation of areas of T. cruzi transmission. Dog infection was shown to not only be an efficient indicator of reduction of wild mammalian fauna richness but to also act as a signal for the presence of small wild mammals with high parasitemia. The lower richness of small mammal species is discussed as a risk factor for the re-emergence of Chagas disease.

  13. La enfermedad de Chagas ya no es tan exótica

    Centers for Disease Control (CDC) Podcasts

    2008-04-03

    Este podcast tiene el propósito de informar a los profesionales de la salud sobre la enfermedad de Chagas, su diagnóstico y tratamiento, así como orientar en la identificación de pacientes infectados.  Created: 4/3/2008 by National Center for Zoonotic, Vector-Borne, and Enteric Diseases (NCZVED).   Date Released: 4/9/2008.

  14. Accurate real-time PCR strategy for monitoring bloodstream parasitic loads in chagas disease patients.

    Directory of Open Access Journals (Sweden)

    Tomas Duffy

    Full Text Available BACKGROUND: This report describes a real-time PCR (Q-PCR strategy to quantify Trypanosoma cruzi (T. cruzi DNA in peripheral blood samples from Chagas disease patients targeted to conserved motifs within the repetitive satellite sequence. METHODOLOGY/PRINCIPAL FINDINGS: The Q-PCR has a detection limit of 0.1 and 0.01 parasites/mL, with a dynamic range of 10(6 and 10(7 for Silvio X10 cl1 (T. cruzi I and Cl Brener stocks (T. cruzi IIe, respectively, an efficiency of 99%, and a coefficient of determination (R(2 of 0.998. In order to express accurately the parasitic loads: (1 we adapted a commercial kit based on silica-membrane technology to enable efficient processing of Guanidine Hydrochloride-EDTA treated blood samples and minimize PCR inhibition; (2 results were normalized incorporating a linearized plasmid as an internal standard of the whole procedure; and (3 a correction factor according to the representativity of satellite sequences in each parasite lineage group was determined using a modified real-time PCR protocol (Lg-PCR. The Q-PCR strategy was applied (1 to estimate basal parasite loads in 43 pediatric Chagas disease patients, (2 to follow-up 38 of them receiving treatment with benznidazole, and (3 to monitor three chronic Chagas heart disease patients who underwent heart-transplantation and displayed events of clinical reactivation due to immunosupression. CONCLUSION/SIGNIFICANCE: All together, the high analytical sensitivity of the Q-PCR strategy, the low levels of intra- and inter-assay variations, as well as the accuracy provided by the Lg-PCR based correction factor support this methodology as a key laboratory tool for monitoring clinical reactivation and etiological treatment outcome in Chagas disease patients.

  15. A scientometric evaluation of the Chagas disease implementation research programme of the PAHO and TDR.

    Directory of Open Access Journals (Sweden)

    Ana Laura Carbajal-de-la-Fuente

    2013-11-01

    Full Text Available The Special Programme for Research and Training in Tropical Diseases (TDR is an independent global programme of scientific collaboration cosponsored by the United Nations Children's Fund, the United Nations Development Program, the World Bank, and the World Health Organization. TDR's strategy is based on stewardship for research on infectious diseases of poverty, empowerment of endemic countries, research on neglected priority needs, and the promotion of scientific collaboration influencing global efforts to combat major tropical diseases. In 2001, in view of the achievements obtained in the reduction of transmission of Chagas disease through the Southern Cone Initiative and the improvement in Chagas disease control activities in some countries of the Andean and the Central American Initiatives, TDR transferred the Chagas Disease Implementation Research Programme (CIRP to the Communicable Diseases Unit of the Pan American Health Organization (CD/PAHO. This paper presents a scientometric evaluation of the 73 projects from 18 Latin American and European countries that were granted by CIRP/PAHO/TDR between 1997 and 2007. We analyzed all final reports of the funded projects and scientific publications, technical reports, and human resource training activities derived from them. Results about the number of projects funded, countries and institutions involved, gender analysis, number of published papers in indexed scientific journals, main topics funded, patents inscribed, and triatomine species studied are presented and discussed. The results indicate that CIRP/PAHO/TDR initiative has contributed significantly, over the 1997-2007 period, to Chagas disease knowledge as well as to the individual and institutional-building capacity.

  16. A scientometric evaluation of the Chagas disease implementation research programme of the PAHO and TDR.

    Science.gov (United States)

    Carbajal-de-la-Fuente, Ana Laura; Yadón, Zaida E

    2013-11-01

    The Special Programme for Research and Training in Tropical Diseases (TDR) is an independent global programme of scientific collaboration cosponsored by the United Nations Children's Fund, the United Nations Development Program, the World Bank, and the World Health Organization. TDR's strategy is based on stewardship for research on infectious diseases of poverty, empowerment of endemic countries, research on neglected priority needs, and the promotion of scientific collaboration influencing global efforts to combat major tropical diseases. In 2001, in view of the achievements obtained in the reduction of transmission of Chagas disease through the Southern Cone Initiative and the improvement in Chagas disease control activities in some countries of the Andean and the Central American Initiatives, TDR transferred the Chagas Disease Implementation Research Programme (CIRP) to the Communicable Diseases Unit of the Pan American Health Organization (CD/PAHO). This paper presents a scientometric evaluation of the 73 projects from 18 Latin American and European countries that were granted by CIRP/PAHO/TDR between 1997 and 2007. We analyzed all final reports of the funded projects and scientific publications, technical reports, and human resource training activities derived from them. Results about the number of projects funded, countries and institutions involved, gender analysis, number of published papers in indexed scientific journals, main topics funded, patents inscribed, and triatomine species studied are presented and discussed. The results indicate that CIRP/PAHO/TDR initiative has contributed significantly, over the 1997-2007 period, to Chagas disease knowledge as well as to the individual and institutional-building capacity. PMID:24244761

  17. [Chagas' disease in patients in chronic hemodialysis. Prevalence and risk of transmission by blood transfusion].

    Science.gov (United States)

    Lorca, M; Lorca, E; Atías, A; Plubins, L

    1989-06-01

    A serologic study of Chagas disease was performed in 110 patients submitted to chronic hemodialisis and blood transfusions. Immunofluorescence antibody testing (IgG and IgM) was positive in 6 out of 62 patients receiving multiple blood transfusions (9.7%), but negative in all 48 subjects without transfusions. Thus, repeated blood transfusion is a significant risk for T cruzi infection in chronic hemodialized patients. PMID:2501847

  18. Evaluation of oral mucosal transudate for immunodiagnosis of Chagas´ disease

    Directory of Open Access Journals (Sweden)

    BARROS Maria das Neves D. S.

    1999-01-01

    Full Text Available Anticorpos anti-Trypanosoma cruzi (isotipo IgG foram detectados no transudato da mucosa oral (TMO através de um ensaio imunoenzimático. Foram estudados 21 indivíduos com doença de Chagas crônica comprovada através de diagnóstico clínico, eletrocardiográfico, epidemiológico e sorológico: 10 com forma cardíaca, 2 com forma digestiva, 6 com forma mista e 3 com forma assintomática. Sete indivíduos de área endêmica, com sorologia negativa, constituiram o grupo controle. O soro destes grupos foi armazenado a -20 oC. A coleta de TMO de ambos os grupos foi realizada com o dispositivo OraSureâ seguindo orientação do fabricante (OraSureâ , Epitope Inc., Beaverton, OR, USA. As amostras de TMO foram diluídas (1:2 e testadas em duplicata através de um ensaio imunoenzimático da Abbott Laboratories para detectar anticorpos IgG contra doença de Chagas. Vinte dos vinte e um pacientes chagásicos apresentaram densidade óptica acima do limiar de reatividade e foram considerados positivos para doença de Chagas. Nenhuma das amostras provenientes de indivíduos soronegativos foi positiva. A sensibilidade e especificidade foram de 95% e 100%, respectivamente. Estes resultados indicam que TMO poderá ser utilizado como um fluido biológico alternativo para o diagnóstico da doença de Chagas. Nós estamos aumentando o número de indivíduos para validar estes resultados incluindo a análise comparativa entre amostras de TMO e soro.

  19. Exposure to Citral, Cinnamon and Ruda Disrupts the Life Cycle of a Vector of Chagas Disease

    OpenAIRE

    C. I. Abramson; E. Aldana; E. Sulbaran

    2007-01-01

    The main vector of Chagas disease in Venezuela was exposed to the odors of citral, cinnamon and ruda. Cinnamon was found to stop the life cycle of Rhodnius prolixus relative to untreated animals. Citral and ruda also influenced the life cycle but not to the extent of animals exposed to cinnamon. We suggest that future research be directed toward using cinnamon in field and toxicity tests.

  20. Development of a Novel Multiplex Immunoassay Multi-cruzi for the Serological Confirmation of Chagas Disease

    OpenAIRE

    Granjon, Elodie; Dichtel-Danjoy, Marie-Laure; Saba, Esber; Sabino, Ester; Campos de Oliveira, Lea; Zrein, Maan

    2016-01-01

    Background Chagas disease is due to the parasite Trypanosoma cruzi, a protist disseminated by a Triatome vector. This disease is endemic to Latin America and considered by WHO as one of the 17 world’s neglected diseases. In Europe and in North America, imported cases are also detected, due to migration of population outside of the endemic region. Diagnosis of T. cruzi infection is usually made indirectly by the detection of specific antibodies to T. cruzi antigens. Following initial diagnosti...

  1. Instantaneous flow field above the free end of finite-height cylinders and prisms

    International Nuclear Information System (INIS)

    Highlights: • PIV measurements of the flow above the free end of finite-height bodies. • Effect of cross-sectional shape of the models on the instantaneous flow. • Small-scale structures generated by the separated shear layer were revealed. • Effect of aspect ratio on the reattachment of the separated flow on the free end. -- Abstract: The flow above the free ends of surface-mounted finite-height circular cylinders and square prisms was studied experimentally using particle image velocimetry (PIV). Cylinders and prisms with aspect ratios of AR = 9, 7, 5, and 3 were tested at a Reynolds number of Re = 4.2 × 104. The bodies were mounted normal to a ground plane and were partially immersed in a turbulent zero-pressure-gradient boundary layer, where the boundary layer thickness relative to the body width was δ/D = 1.6. PIV measurements were made above the free ends of the bodies in a vertical plane aligned with the flow centreline. The present PIV results provide insight into the effects of aspect ratio and body shape on the instantaneous flow field. The recirculation zone under the separated shear layer is larger for the square prism of AR = 3 compared to the more slender prism of AR = 9. Also, for a square prism with low aspect ratio (AR = 3), the influence of the reverse flow over the free end surface becomes more significant compared to that for a higher aspect ratio (AR = 9). For the circular cylinder, a cross-stream vortex forms within the recirculation zone. As the aspect ratio of the cylinder decreases, the reattachment point of the separated flow on the free end surface moves closer to the trailing edge. For both the square prism and circular cylinder cases, the instantaneous velocity vector field and associated in-plane vorticity field revealed small-scale structures mostly generated by the separated shear layer

  2. Polymorphisms of toll-like receptor 2 and 4 genes in Chagas disease

    Directory of Open Access Journals (Sweden)

    German Zafra

    2008-02-01

    Full Text Available The aim of this study was to test the possible implication of toll-like receptor 2 (TLR2 and TLR4 gene polymorphisms in determining the susceptibility to Chagas' disease. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism in 475 individuals from Colombia, 143 seropositive with chagasic cardiomyopathy, 132 seropositive asymptomatic and 200 seronegative. The TLR2 arginine to glutamine substitution at residue 753(Arg753Gln polymorphism was absent in the groups analyzed. The TLR4 Asp299Gly and Thr399Ile polymorphisms are in linkage disequilibrium and we observed a very low frequency of these polymorphisms in our study population (2.6% and 1.8% respectively. The overall TLR2 and TLR4 alleles and genotype distribution in seronegative and seropositive were not significantly different. We compared the frequencies between asymptomatic patients and those with chagasic cardiomyopathy and we did not observe any significant differences in the distribution of alleles or genotypes. In summary, this study corroborates the low frequency of TLR2 and TLR4 polymorphisms observed in other populations and suggest that these do not play an important role in Chagas' disease. The validation of these findings in independent cohorts is needed to firmly establish a role for TLR2 and TLR4 variants in Chagas' disease.

  3. Working conditions of Chagas' disease patients in a large Brazilian city

    Directory of Open Access Journals (Sweden)

    Maria Elena Guariento

    1999-04-01

    Full Text Available This study evaluated the working conditions of Chagas' disease patients in the city of Campinas, São Paulo, focusing on two-hundred-fifty patients with steady employment and treated at the University Hospital (HC-FCM/Unicamp: 98% were working-age and 77.6% were men. The origin of the patients reflected the migratory process occurring among this population. Most of the patients had limited professional skills, while 63.6% had not finished primary school and 21.6% were illiterate. However, 63.6% were regularly employed under duly processed work contracts. Their jobs were mainly in general services (21.6% and heavy industry (21.2%. Some 55% of the patients reported a monthly income less than or equal to U$100.00, and 40.4% reported having been fired at least once during the last ten years, in 8.9% of the cases because of a diagnosis of Chagas' disease. Of the patients undergoing pre-hiring physical examinations (57.2%, 9.1% were refused, 92.3% of whom due to positive serology for T. cruzi. Finally, 78.4% reported not belonging to a labor union. The study demonstrated the precarious working conditions and discrimination experienced by workers with Chagas' disease.

  4. Positive deviance study to inform a Chagas disease control program in southern Ecuador

    Directory of Open Access Journals (Sweden)

    Claudia Nieto-Sanchez

    2015-05-01

    Full Text Available Chagas disease is caused by Trypanosoma cruzi, which is mainly transmitted by the faeces of triatomine insects that find favourable environments in poorly constructed houses. Previous studies have documented persistent triatomine infestation in houses in the province of Loja in southern Ecuador despite repeated insecticide and educational interventions. We aim to develop a sustainable strategy for the interruption of Chagas disease transmission by promoting living environments that are designed to prevent colonisation of rural houses by triatomines. This study used positive deviance to inform the design of an anti-triatomine prototype house by identifying knowledge, attitudes and practices used by families that have remained triatomine-free (2010-2012. Positive deviants reported practices that included maintenance of structural elements of the house, fumigation of dwellings and animal shelters, sweeping with "insect repellent" plants and relocation of domestic animals away from the house, among others. Participants favoured construction materials that do not drastically differ from those currently used (adobe walls and tile roofs. They also expressed their belief in a clear connection between a clean house and health. The family's economic dynamics affect space use and must be considered in the prototype's design. Overall, the results indicate a positive climate for the introduction of housing improvements as a protective measure against Chagas disease in this region.

  5. Multi-epitope proteins for improved serological detection of Trypanosoma cruzi infection and Chagas Disease.

    Science.gov (United States)

    Duthie, Malcolm S; Guderian, Jeffery A; Vallur, Aarthy C; Misquith, Ayesha; Liang, Hong; Mohamath, Raodoh; Luquetti, Alejandro O; Carter, Darrick; Tavares, Suelene N B; Reed, Steven G

    2016-03-01

    We previously reported that tandem repeat (TR) proteins from Trypanosoma cruzi could serve as targets of the antibody response and be useful as diagnostic indicators. To optimize reagents for detecting T. cruzi infection we evaluated individual TR proteins and identified several that were recognized by the majority of Chagas patient's sera collected from individuals form Brazil. We then produced novel, recombinant fusion proteins to combine the reactive TR proteins into a single diagnostic product. Direct comparison of the antibody response of serum samples that were readily detected by the established fusion antigen used in commercial detection of Chagas disease, TcF, revealed strong responses to TcF43 and TcF26 proteins. While the TcF43 and TcF26 antigens enhanced detection and strength of signal, they did not compromise the specificity of detection compared to that obtained with TcF. Finally, it was apparent by testing against a panel of 84 serum samples assembled on the basis of moderate or weak reactivity against TcF (mostly signal:noise detected by many of the sera that had low TcF antibody levels. Taken together, these data indicate that TcF43 and TcF26 could be used to enhance the detection of T. cruzi infection as well as supporting a diagnosis of Chagas disease.

  6. The building and simulation of color analytical model based on prism dispersion

    Science.gov (United States)

    Yu, Xun; Li, Xiaoming; Wang, Yawei

    2015-02-01

    The color based on prism dispersion was analyzed and the mathematical model was established in this paper. Firstly, based on Dan Bruton's research, the mapping relationship between visible wavelength and data in color map matrix was created, the geometric data of color after dispersion of the prism was processed with least squares curve fitting, then the mapping relationship between wavelength and the refractive index was built. Secondly, on the basis of the work before, the mapping relationship between wavelength and projection geometry was built. Finally, through the building of color management system, the characterization of spectral lines and colors in LAB color space would be got.

  7. Evaluation of the Performance of Routine Information System Management (PRISM framework: evidence from Uganda

    Directory of Open Access Journals (Sweden)

    Aqil Anwer

    2010-07-01

    Full Text Available Abstract Background Sound policy, resource allocation and day-to-day management decisions in the health sector require timely information from routine health information systems (RHIS. In most low- and middle-income countries, the RHIS is viewed as being inadequate in providing quality data and continuous information that can be used to help improve health system performance. In addition, there is limited evidence on the effectiveness of RHIS strengthening interventions in improving data quality and use. The purpose of this study is to evaluate the usefulness of the newly developed Performance of Routine Information System Management (PRISM framework, which consists of a conceptual framework and associated data collection and analysis tools to assess, design, strengthen and evaluate RHIS. The specific objectives of the study are: a to assess the reliability and validity of the PRISM instruments and b to assess the validity of the PRISM conceptual framework. Methods Facility- and worker-level data were collected from 110 health care facilities in twelve districts in Uganda in 2004 and 2007 using records reviews, structured interviews and self-administered questionnaires. The analysis procedures include Cronbach's alpha to assess internal consistency of selected instruments, test-retest analysis to assess the reliability and sensitivity of the instruments, and bivariate and multivariate statistical techniques to assess validity of the PRISM instruments and conceptual framework. Results Cronbach's alpha analysis suggests high reliability (0.7 or greater for the indices measuring a promotion of a culture of information, RHIS tasks self-efficacy and motivation. The study results also suggest that a promotion of a culture of information influences RHIS tasks self-efficacy, RHIS tasks competence and motivation, and that self-efficacy and the presence of RHIS staff have a direct influence on the use of RHIS information, a key aspect of RHIS performance

  8. Design of an Airborne Portable Remote Imaging Spectrometer (PRISM) for the Coastal Ocean

    Science.gov (United States)

    Mouroulis, P.; vanGorp, B.; Green, R. O.; Cohen, D.; Wilson, D.; Randall, D.; Rodriguez, J.; Polanco, O.; Dierssen, H.; Balasubramanian, K.; Vargas, R.; Hein, R.; Sobel, H.; Eastwood, M.

    2010-01-01

    PRISM is a pushbroom imaging spectrometer currently under development at the Jet Propulsion Laboratory, intended to address the needs of airborne coastal ocean science research. We describe here the instrument design and the technologies that enable it to achieve its distinguishing characteristics. PRISM covers the 350-1050 nm range with a 3.1 nm sampling and a 33(deg) field of view. The design provides for high signal to noise ratio, high uniformity of response, and low polarization sensitivity. The complete instrument also incorporates two additional wavelength bands at 1240 and 1610 nm in a spot radiometer configuration to aid with atmospheric correction.

  9. Efficient broadband second-harmonic generation by dispersive achromatic nonlinear conversion using only prisms

    Energy Technology Data Exchange (ETDEWEB)

    Richman, B.A.; Bisson, S.E.; Trebino, R.

    1997-12-01

    Using a lossless dispersive apparatus consisting of six prisms, optimized to match a second-harmonic crystal phase-matching angle vs. wavelength to second order, we efficiently doubled tunable fundamental light near 660 nm over a range of 80 nm using a 4-mm-long type-I {beta}-Barium Borate (BBO) crystal. Another lossless set of six prisms after the crystal realigned the propagation directions of the various second-harmonic frequencies to be collinear to within 1/4 spot diameter in position and 200 {mu}rad in angle. The measured conversion efficiency of a 40-mJ, 5-ns fundamental pulse was 10%.

  10. Optimization studies for the prism alternative oxide core, and its response to the actinide burning strategy

    International Nuclear Information System (INIS)

    The PRISM advanced liquid metal reactor is designed by General Electric in a reference solution equipped by a metal fuelled core. An alternative oxide core is studied by General Electric and ENEA in the frame of a collaboration existing since 1989. This paper deals with the ENEA contribution on the oxide solution, aimed at the core optimization both from safety parameters and fuel cycle economy points of view. Moreover, synthetic information about ENEA evaluations about the minor actinide burning capability of the PRISM oxide core are given. (author)

  11. A Novel Method for Heightening Sensitivity of Prism Coupler-Based SPR Sensor

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-Wei; WEN Ting-Dun; WU Zhi-Fang

    2011-01-01

    We present a novel method for heightening the sensitivity of a prism coupler-based surface plasmon resonance (SPR) sensor. The method is based on the total reflection prism made of BK7 glass combined with the Kretschmann geometry of theattenuated total reflection (ATR) method. Compared to the conventional methods of prism coupler-based SPR the novel method provides higher semsitivity to the measurement system.Theoretical simulations show that the detetion sensitivity to the refractive index (RI) of the sensor based on the novel approach has a strong dependence on the thickness of the metal layer. The RI resolution of the sensor is predicted to be 8 × 107 refractive indox units (RIU) under the condition of optimum metal film thickness.This novel method can leave out a precision angle rotation device in the angle modulation and it is unnecessary to adjust the acceptance angle of the light detector. The principal advantage of this method over other methods of light intensity modulation based on prism coupler-based SPR is high sensitivity, expediency to measure and aplication of long distances.%@@ We present a novel method for heightening the sensitivity of a prism coupler-based surface plasmon resonance(SPR) sensor.The method is based on the total reflection prism made of BK7 glass combined with the Kretschmann geometry of theattenuated total reflection(ATR) method.Compared to the conventional methods of prism coupler-based SPR,the novel method provides higher sensitivity to the measurement system.Theoretical simulations show that the detection sensitivity to the refractive index(RI) of the sensor based on the novel approach has a strong dependence on the thickness of the metal layer.The RI resolution of the sensor is predicted to be 8 × 10-7 refractive index units(RIU) under the condition of optimum metal film thickness.This novel method can leave out a precision angle rotation device in the angle modulation and it is unnecessary to adjust the acceptance angle of

  12. Prevalence of Chagas disease in Latin-American migrants living in Europe: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Ana Requena-Méndez

    2015-02-01

    Full Text Available Few studies have assessed the burden of Chagas disease in non-endemic countries and most of them are based on prevalence estimates from Latin American (LA countries that likely differ from the prevalence in migrants living in Europe. The aim of this study was to systematically review the existing data informing current understanding of the prevalence of Chagas disease in LA migrants living in European countries.We conducted a systematic review and meta-analysis of studies reporting prevalence of Chagas disease in European countries belonging to the European Union (EU before 2004 in accordance with the MOOSE guidelines and based on the database sources MEDLINE and Global Health. No restrictions were placed on study date, study design or language of publication. The pooled prevalence was estimated using random effect models based on DerSimonian & Laird method.We identified 18 studies conducted in five European countries. The random effect pooled prevalence was 4.2% (95%CI:2.2-6.7%; and the heterogeneity of Chagas disease prevalence among studies was high (I2 = 97%,p<0.001. Migrants from Bolivia had the highest prevalence of Chagas disease (18.1%, 95%CI:13.9-22.7%.Prevalence of Chagas in LA migrants living in Europe is high, particularly in migrants from Bolivia and Paraguay. Data are highly heterogeneous dependent upon country of origin and within studies of migrants from the same country of origin. Country-specific prevalence differs from the estimates available from LA countries. Our meta-analysis provides prevalence estimates of Chagas disease that should be used to estimate the burden of disease in European countries.

  13. 3D Geostatistical interpolation and geological interpretation of paleo-groundwater rise in the Holocene coastal prism in the Netherlands

    NARCIS (Netherlands)

    Cohen, K.M.

    2005-01-01

    Coastal-prism sediments record rising local water levels, forced by sea-level rise. Sea-level rise is the primary driving factor, but the anatomy of the coastal prism is a result of a complex interplay of sea level, subsidence, and upstream controls (essentially sediment load). The sedimentary archi

  14. Melatonin in Chagas´ disease: Possible therapeutic value La melatonina en la enfermedad de Chagas: Su posible valor terapéutico

    Directory of Open Access Journals (Sweden)

    Daniel P. Cardinali

    2011-10-01

    Full Text Available Chagas' disease is a severe health problem in Latin America, causing approximately 50 000 deaths a year, with approximately 18 million infected people. About 25-30% of the patients infected with Trypanosoma cruzi develop the chronic form of the disease. The protective response against T. cruzi depends on both innate and acquired immunity involving macrophages, natural killer cells, T and B lymphocytes, and the production of proinflammatory Th-1 cytokines. In addition, an increased nitric oxide (NO production in macrophages leading to effective microbicidal action is needed to control parasitemia. Melatonin is detectable in T. cruzi and may play a role in promoting infection whereas, when administered in high doses during the acute phase of T. cruzi infection, it can decrease parasitemia while reducing NO production. During chronic disease progression, the sustained oxidative stress concomitant to myocardial damage could be reduced by administering melatonin. It is hypothesized that the coordinated administration of a melatonin agonist like the MT1/MT2 agonist ramelteon, that lacks antioxidant activity and may not affect NO production during the acute phase, and of melatonin in doses high enough to decrease oxidative damage, to preserve mitochondrial and to prevent cardiomyopathy during the chronic phase, could be a novel add-on treatment of Chagas´ disease.La enfermedad de Chagas es un problema grave de salud en América Latina, causando cerca de 50 000 muertes al año y unos 18 millones de infectados. Alrededor del 25-30% de los pacientes infectados con Trypanosoma cruzi desarrollan la forma crónica de la enfermedad. La respuesta de defensa ante el T. cruzi depende de la inmunidad innata y adquirida con la participación de macrófagos, células “natural killer”, linfocitos T y B, y la producción de citoquinas proinflamatorias de tipo Th-1. Además, el aumento en la producción de óxido nítrico (NO en los macrófagos lleva a una acci

  15. Enfermedad de Chagas en poblaciones prehistóricas del norte de Chile Chagas disease in prehistoric populations of northern Chile

    Directory of Open Access Journals (Sweden)

    NANCY ORELLANA-HALKYER

    2010-12-01

    Full Text Available La enfermedad de Chagas es producida por el parásito Trypanosoma cruzi, el cual afecta tanto a seres humanos como a animales, en particular mamíferos marsupiales y placentarios. Las vías de transmisión son diversas, siendo una de las más importantes la vía vectorial, en la que participan insectos infectados con este parásito, animales y humanos. En este artículo de revisión discutimos los postulados sobre la vía de transmisión oral, los hallazgos de T. cruzi en momias de América y especialmente en las del norte de Chile. Presentamos además información que apunta a que la enfermedad de Chagas estuvo presente mucho antes de la conquista europea y de la construcción de viviendas de adobe. Comentamos las hipótesis sobre el vector domiciliado más importante de Sudamérica, Triatoma infestans, su antigüedad en la costa de Arica y los reportes más recientes de otros vectores silvestres. También se discute la información relacionada a la participación en el ciclo de T. cruzi de distintos mamíferos silvestres de Chile y asimismo proponemos el estudio paleoparasitológico en restos zooarqueológicos para conocer las especies de mamíferos reservónos de T. cruzi en la antigüedad.Chagas diseases is produced by a parasite named Trypanosoma cruzi, that affects humans and other marsupial and placental mammals. Transmission routes are diverse, but the most important transmission is the vector route, which involves the triatomine insects, wild and domestic infected animáis, and humans. Here we review the data about oral transmission route and the evidences of the etiological agent (Trypanosoma cruzi of Chagas disease in pre-Columbian American mummies, making a critical review of the infection in northern Chile. Moreover, we comment on the hypotheses suggested in relation to the most important vector of the infection in South América Triatoma infestans, its antiquity in the Arica coast, and the recent reports about other wild infected

  16. Chagas disease: what is known and what is needed - A background article

    Directory of Open Access Journals (Sweden)

    José Rodrigues Coura

    2007-10-01

    Full Text Available Chagas disease began millions of years ago as an enzootic disease of wild animals and started to be transmitted to man accidentally in the form of an anthropozoonosis when man invaded wild ecotopes. Endemic Chagas disease became established as a zoonosis over the last 200-300 years through forest clearance for agriculture and livestock rearing and adaptation of triatomines to domestic environments and to man and domestic animals as a food source. It is estimated that 15 to 16 million people are infected with Trypanosoma cruzi in Latin America and 75 to 90 million people are exposed to infection. When T. cruzi is transmitted to man through the feces of triatomines, at bite sites or in mucosa, through blood transfusion or orally through contaminated food, it invades the bloodstream and lymphatic system and becomes established in the muscle and cardiac tissue, the digestive system and phagocytic cells. This causes inflammatory lesions and immune responses, particularly mediated by CD4+, CD8+, interleukin-2 (IL and IL-4, with cell and neuron destruction and fibrosis, and leads to blockage of the cardiac conduction system, arrhythmia, cardiac insufficiency, aperistalsis, and dilatation of hollow viscera, particularly the esophagus and colon. T. cruzi may also be transmitted from mother to child across the placenta and through the birth canal, thus causing abortion, prematurity, and organic lesions in the fetus. In immunosuppressed individuals, T. cruzi infection may become reactivated such that it spreads as a severe disease causing diffuse myocarditis and lesions of the central nervous system. Chagas disease is characterized by an acute phase with or without symptoms, and with entry point signs (inoculation chagoma or Romaña's sign, fever, adenomegaly, hepatosplenomegaly, and evident parasitemia, and an indeterminate chronic phase (asymptomatic, with normal results from electrocardiogram and x-ray of the heart, esophagus, and colon or with a

  17. PRISM, a Novel Visual Metaphor Measuring Personally Salient Appraisals, Attitudes and Decision-Making: Qualitative Evidence Synthesis.

    Directory of Open Access Journals (Sweden)

    Tom Sensky

    Full Text Available PRISM (the Pictorial Representation of Illness and Self Measure is a novel, simple visual instrument. Its utility was initially discovered serendipitously, but has been validated as a quantitative measure of suffering. Recently, new applications for different purposes, even in non-health settings, have encouraged further exploration of how PRISM works, and how it might be applied. This review will summarise the results to date from applications of PRISM and propose a generic conceptualisation of how PRISM works which is consistent with all these applications.A systematic review, in the form of a qualitative evidence synthesis, was carried out of all available published data on PRISM.Fifty-two publications were identified, with a total of 8254 participants. Facilitated by simple instructions, PRISM has been used with patient groups in a variety of settings and cultures. As a measure of suffering, PRISM has, with few exceptions, behaved as expected according to Eric Cassell's seminal conceptualisation of suffering. PRISM has also been used to assess beliefs about or attitudes to stressful working conditions, interpersonal relations, alcohol consumption, and suicide, amongst others.This review supports PRISM behaving as a visual metaphor of the relationship of objects (eg 'my illness' to a subject (eg 'myself' in a defined context (eg 'my life at the moment'. As a visual metaphor, it is quick to complete and yields personally salient information. PRISM is likely to have wide applications in assessing beliefs, attitudes, and decision-making, because of its properties, and because it yields both quantitative and qualitative data. In medicine, it can serve as a generic patient-reported outcome measure. It can serve as a tool for representational guidance, can be applied to developing strategies visually, and is likely to have applications in coaching, psychological assessment and therapeutic interventions.

  18. PRISM, a Novel Visual Metaphor Measuring Personally Salient Appraisals, Attitudes and Decision-Making: Qualitative Evidence Synthesis

    Science.gov (United States)

    Sensky, Tom; Büchi, Stefan

    2016-01-01

    Background PRISM (the Pictorial Representation of Illness and Self Measure) is a novel, simple visual instrument. Its utility was initially discovered serendipitously, but has been validated as a quantitative measure of suffering. Recently, new applications for different purposes, even in non-health settings, have encouraged further exploration of how PRISM works, and how it might be applied. This review will summarise the results to date from applications of PRISM and propose a generic conceptualisation of how PRISM works which is consistent with all these applications. Methods A systematic review, in the form of a qualitative evidence synthesis, was carried out of all available published data on PRISM. Results Fifty-two publications were identified, with a total of 8254 participants. Facilitated by simple instructions, PRISM has been used with patient groups in a variety of settings and cultures. As a measure of suffering, PRISM has, with few exceptions, behaved as expected according to Eric Cassell’s seminal conceptualisation of suffering. PRISM has also been used to assess beliefs about or attitudes to stressful working conditions, interpersonal relations, alcohol consumption, and suicide, amongst others. Discussion This review supports PRISM behaving as a visual metaphor of the relationship of objects (eg ‘my illness’) to a subject (eg ‘myself’) in a defined context (eg ‘my life at the moment’). As a visual metaphor, it is quick to complete and yields personally salient information. PRISM is likely to have wide applications in assessing beliefs, attitudes, and decision-making, because of its properties, and because it yields both quantitative and qualitative data. In medicine, it can serve as a generic patient-reported outcome measure. It can serve as a tool for representational guidance, can be applied to developing strategies visually, and is likely to have applications in coaching, psychological assessment and therapeutic interventions. PMID

  19. Aspectos neurológicos da doença de chagas: sistema nervoso central

    Directory of Open Access Journals (Sweden)

    Sylvio de Vergueiro Forjaz

    1967-09-01

    Full Text Available The lesions of the nervous system in the Trypanosomiasis Cruzi are quite frequent and are not only limited to the encephalo-spinal-axis. Actually, they are much more common in the peripheral representations of the autonomic nervous system, resulting in the so-called enteromegalies (mega-esophagus, megacolon, etc. so frequent in Brazil. However, only the clinical manifestations due to the encephalic and spinal lesions have been included in the neurological aspects of Chagas' disease (as formerly contended for by Carlos Chagas. In the acute phase of the central nervous system infestation, the Trypanosoma cruzi,as leishmanias, is found in cellular elements of the neuroglia (microglia, astroglia and may be isolated from the peripheral blood and cerebrospinal fluid (inoculation in sensitive animals. The corresponding clinical manifestations are the severe difuse meningo-encephalo-myelitis with a high degree of lethality and also signs of infection, hepatomegaly and splenomegaly. The infants from endemic areas are much more compromised. The clinical-pathologic as well as experimental confirmations on that acute phase of the disease are numerous and irrefutable. In the chronic phase of the disease, the neurological manifestations are not very clear. Early in 1909, Chagas, impressed with the great number of cases of infantile encephalopathy found in infested regions, imputed to the T. cruzithe etiology of such cases of encephalopathy and considered them as pertaining to a chronic phase of the disease. This has not been confirmed by other investigations, and even if the etiologic agent were the T. cruzithe clinical manifestations have no evolutive character and seem more sequelae than symptoms of a real chronic nervous phase. Even experimentally it has not been possible to demonstrate the presence of parasites in the nervous system of infested animals after clearing of the signs of the acute phase. In patients with chronic Chagas' disease with lesions in

  20. [The assessment process within science and the nomination of Carlos Chagas for the Nobel prize for Physiology or Medicine].

    Science.gov (United States)

    Pittella, José Eymard Homem

    2009-01-01

    One of the greatest achievements in the history of medicine was the description of Chagas disease by the physician and scientist Carlos Chagas. A hundred years after the discovery of the disease, speculation still remains regarding the two official nominations of Carlos Chagas for the Nobel Prize, the biggest worldwide scientific award, in 1913 and in 1921. It has been accepted that the reason why the prize was not awarded to this brilliant scientist may have been the strong opposition that he faced in Brazil, from some physicians and researchers of that time. They went as far as questioning the existence of Chagas disease, thereby possibly influencing the decision of the Nobel Committee not to award the prize to him. Analysis of the database of the Nobel prize archives, with the revelation of the names of nominators, nominees and prizewinners spanning the years 1901-1951, brought information not only about what was considered to be a scientific achievement at that time, but also about who the important scientists were and what the relationships between them were. The non-recognition of Carlos Chagas' discoveries by the Nobel Committee appears to be more correctly explained by these factors than by the negative impact of the local opposition. PMID:19287939

  1. Clinical forms of Trypanosoma cruzi infected individuals in the chronic phase of Chagas disease in Puebla, Mexico

    Directory of Open Access Journals (Sweden)

    María del Carmen Sánchez-Guillén

    2006-11-01

    Full Text Available In Mexico, despite the relatively high seroprevalence of Trypanosoma cruzi infection in humans in some areas, reported morbidity of Chagas disease is not clear. We determined clinical stage in 71 individuals seropositive to T. cruzi in the state of Puebla, Mexico, an area endemic for Chagas disease with a reported seroprevalence of 7.7%. Diagnosis of Chagas disease was made by two standardized serological tests (ELISA, IHA. Individuals were stratified according to clinical studies. All patients were submitted to EKG, barium swallow, and barium enema. Groups were identified as indeterminate form (IF asymptomatic individuals without evidence of abnormalities (n = 34 cases; those with gastrointestinal alterations (12 patients including symptoms of abnormal relaxation of the lower esophageal sphincter and absent peristalsis in the esophageal body, grade I megaesophagus, and/or megacolon; patients with clinical manifestations and documented changes of chronic Chagas heart disease who were subdivided as follows: mild (8 patients - mild electrocardiographic changes of ventricular repolarization, sinus bradychardia; moderate (6 patients - left bundle branch block, right bundle branch block associated with left anterior fascicular block; severe (8 patients - signs of cardiomegaly, dilated cardiomyopathy; and the associated form (3 cases that included presence of both cardiomyopathy and megaesophagus. These data highlight the importance of accurate evaluation of the prevalence and clinical course of Chagas disease in endemic and non-endemic areas of Mexico.

  2. Understanding University Reform in Japan through the Prism of the Social Sciences

    Science.gov (United States)

    Goodman, Roger

    2008-01-01

    This article looks at current university reforms in Japan through two slightly different social science prisms: how social science methodologies and theories can help us understand those reforms better and how social science teaching in universities will be affected by the current reform processes. (Contains 3 tables and 7 notes.)

  3. Indirect versus direct feedback in computer-based Prism Adaptation Therapy

    DEFF Research Database (Denmark)

    Wilms, Inge Linda; Rytter, Hana Malá

    2010-01-01

    Prism Adaptation Therapy (PAT) is an intervention method in the treatment of the attention disorder neglect (Frassinetti, Angeli, Meneghello, Avanzi, & Ladavas, 2002; Rossetti, et al., 1998). The aim of this study was to investigate whether one session of PAT using a computer-attached touchscreen...

  4.   Indirect versus direct feedback in computer-based Prism Adaptation Therapy

    DEFF Research Database (Denmark)

    Wilms, Inge Linda; Rytter, Hana Malá

    2010-01-01

      Prism Adaptation Therapy (PAT) is an intervention method in the treatment of the attention disorder neglect (Frassinetti, Angeli, Meneghello, Avanzi, & Ladavas, 2002; Rossetti, et al., 1998). The aim of this study was to investigate whether one session of PAT using a computer-attached touchscreen...

  5. Nonlinear attractor dynamics in the fundamental and extended prism adaptation paradigm

    International Nuclear Information System (INIS)

    Adaptation and re-adaptation processes are studied in terms of dynamic attractors that evolve and devolve. In doing so, a theoretical account is given for the fundamental observation that adaptation and re-adaptation processes do not exhibit one-trial learning. Moreover, the emergence of the latent aftereffect in the extended prism paradigm is addressed

  6. Development and application of GIS-based PRISM integration through a plugin approach

    Science.gov (United States)

    Lee, Woo-Seop; Chun, Jong Ahn; Kang, Kwangmin

    2014-05-01

    A PRISM (Parameter-elevation Regressions on Independent Slopes Model) QGIS-plugin was developed on Quantum GIS platform in this study. This Quantum GIS plugin system provides user-friendly graphic user interfaces (GUIs) so that users can obtain gridded meteorological data of high resolutions (1 km × 1 km). Also, this software is designed to run on a personal computer so that it does not require an internet access or a sophisticated computer system. This module is a user-friendly system that a user can generate PRISM data with ease. The proposed PRISM QGIS-plugin is a hybrid statistical-geographic model system that uses coarse resolution datasets (APHRODITE datasets in this study) with digital elevation data to generate the fine-resolution gridded precipitation. To validate the performance of the software, Prek Thnot River Basin in Kandal, Cambodia is selected for application. Overall statistical analysis shows promising outputs generated by the proposed plugin. Error measures such as RMSE (Root Mean Square Error) and MAPE (Mean Absolute Percentage Error) were used to evaluate the performance of the developed PRISM QGIS-plugin. Evaluation results using RMSE and MAPE were 2.76 mm and 4.2%, respectively. This study suggested that the plugin can be used to generate high resolution precipitation datasets for hydrological and climatological studies at a watershed where observed weather datasets are limited.

  7. Empirical relationship between inlet cross-sectional area and tidal prism: A re-evaluation

    NARCIS (Netherlands)

    Stive, M.J.F.; Ji, L.; Brouwer, R.L.; Van de Kreeke, J.; Ranasinghe, R.W.M.R.J.B.

    2010-01-01

    The well-known empirical relationship between the equilibrium cross-sectional area of tidal inlet entrances (A) and the tidal prism (P), first developed by O’Brien (1931), has been extensively reviewed. Our theoretical investigations indicate that a unique A-P relationship should only be expected fo

  8. Family Perspectives: Using a Cultural Prism to Understand Families from Asian Cultural Backgrounds

    Science.gov (United States)

    Lee, Suk-Hyang; Turnbull, Ann P.; Zan, Fei

    2009-01-01

    Educators can better serve students who come from diverse cultural backgrounds by understanding the differing cultural values of these students and their families. This article explores different cultural perspectives using a cultural prism approach, focused most specifically on the Korean and Chinese cultures. (Contains 2 tables.)

  9. Two-pass-internal second-harmonic generation using a prism coupler.

    Science.gov (United States)

    Gonzalez, D. G.; Nieh, S. T. K.; Steier, W. H.

    1973-01-01

    A dispersive quartz prism is used to couple the total second harmonic generated in both directions by an internal cavity frequency doubler. The study shows that the dispersion of air and mirror reflection phase shifts can be compensated for by a slight nonphase match condition in the doubler.

  10. Tidal Prism Modeling of Phytoplankton and Nitrogen Concentrations in Narragansett Bay and its Sub-Embayments

    Science.gov (United States)

    A tidal prism model was developed to calculate temporal changes in the spatially averaged concentration of three state variables: phytoplankton, dissolved inorganic nitrogen, and detritus. Our main objective was to develop a model to help us understand the causes of phytoplankton...

  11. Novel laterally pumped by prism laser configuration for compact solid-state lasers

    International Nuclear Information System (INIS)

    We propose a new laser configuration in which the pump radiation is coupled into the laser crystal through a prism. The laser medium is square shaped and the prism is attached on one of its lateral sides, near one of the crystal extremities. The diode-laser fiber end is placed close to the prism hypotenuse, the pump radiation is coupled into the laser crystal through the opposite surface of the prism and propagates into the crystal through total internal reflections. This laser geometry is simple to align and permits the realization of compact diode-pumped laser systems, as well as power scaling. A diode-pumped Nd:YAG laser yielding pulses of 2.1 mJ energy under a pump with pulses of 9.9 mJ is demonstrated. The laser slope efficiency is 0.22. Furthermore, this geometry enables one to obtain passively Q-switched lasers with the saturable absorber crystal placed between the resonator high-reflectivity mirror and the laser crystal. A Nd:YAG laser, passively Q-switched by a Cr4+:YAG crystal with initial transmission T0 = 0.90, delivering laser output with a pulsed energy of 93 μJ, a duration of 26 ns and a pump threshold of 1.9 mJ, is realized in order to prove the concept. (letter)

  12. COMET and PRISM - Search for Charged Lepton Flavor Violation with Muons

    International Nuclear Information System (INIS)

    The experiment (COMET) at J-PARC to search for a charged-lepton-flavor-violating process of muon to electron conversion in a muonic atom is described. Future prospects of an experiment (PRISM) with even higher sensitivity is mentioned. On-going R and D on a highly intense muon source (MuSIC) at Osaka University is presented.

  13. Measurement of separator contact forces in ball bearings using a derotation prism

    Science.gov (United States)

    Nypan, L. J.

    1978-01-01

    A derotation prism was used to produce a stationary image of balls deflecting a portion of the separator. Ball to cage contact forces in a 110 mm bearing at speeds to 12,000 rpm were found to be 25 N (five lb) maximum. Inner race land contact force was found to vary up to 20 N (four lb).

  14. A Novel Method for Heightening Sensitivity of Prism Coupler-Based SPR Sensor

    International Nuclear Information System (INIS)

    We present a novel method for heightening the sensitivity of a prism coupler-based surface plasmon resonance (SPR) sensor. The method is based on the total reflection prism made of BK7 glass combined with the Kretschmann geometry of theattenuated total reflection (ATR) method. Compared to the conventional methods of prism coupler-based SPR, the novel method provides higher sensitivity to the measurement system. Theoretical simulations show that the detection sensitivity to the refractive index (RI) of the sensor based on the novel approach has a strong dependence on the thickness of the metal layer. The RI resolution of the sensor is predicted to be 8 × 10−7 refractive index units (RIU) under the condition of optimum metal film thickness. This novel method can leave out a precision angle rotation device in the angle modulation and it is unnecessary to adjust the acceptance angle of the light detector. The principal advantage of this method over other methods of light intensity modulation based on prism coupler-based SPR is high sensitivity, expediency to measure and application of long distances. (fundamental areas of phenomenology(including applications))

  15. PRISM (Polarized Radiation Imaging and Spectroscopy Mission): an extended white paper

    NARCIS (Netherlands)

    André, Philippe; Baccigalupi, Carlo; Banday, Anthony; Barbosa, Domingos; Barreiro, Belen; Bartlett, James; Bartolo, Nicola; Battistelli, Elia; Battye, Richard; Bendo, George; Benoît, Alain; Bernard, Jean-Philippe; Bersanelli, Marco; Béthermin, Matthieu; Bielewicz, Pawel; Bonaldi, Anna; Bouchet, François; Boulanger, François; Brand, Jan; Bucher, Martin; Burigana, Carlo; Cai, Zhen-Yi; Camus, Philippe; Casas, Francisco; Casasola, Viviana; Castex, Guillaume; Challinor, Anthony; Chluba, Jens; Chon, Gayoung; Colafrancesco, Sergio; Comis, Barbara; Cuttaia, Francesco; D'Alessandro, Giuseppe; Da Silva, Antonio; Davis, Richard; de Avillez, Miguel; de Bernardis, Paolo; de Petris, Marco; de Rosa, Adriano; de Zotti, Gianfranco; Delabrouille, Jacques; Désert, François-Xavier; Dickinson, Clive; Diego, Jose Maria; Dunkley, Joanna; Enßlin, Torsten; Errard, Josquin; Falgarone, Edith; Ferreira, Pedro; Ferrière, Katia; Finelli, Fabio; Fletcher, Andrew; Fosalba, Pablo; Fuller, Gary; Galli, Silvia; Ganga, Ken; García-Bellido, Juan; Ghribi, Adnan; Giard, Martin; Giraud-Héraud, Yannick; Gonzalez-Nuevo, Joaquin; Grainge, Keith; Gruppuso, Alessandro; Hall, Alex; Hamilton, Jean-Christophe; Haverkorn, Marijke; Hernandez-Monteagudo, Carlos; Herranz, Diego; Jackson, Mark; Jaffe, Andrew; Khatri, Rishi; Kunz, Martin; Lamagna, Luca; Lattanzi, Massimiliano; Leahy, Paddy; Lesgourgues, Julien; Liguori, Michele; Liuzzo, Elisabetta; Lopez-Caniego, Marcos; Macias-Perez, Juan; Maffei, Bruno; Maino, Davide; Mangilli, Anna; Martinez-Gonzalez, Enrique; Martins, Carlos J. A. P.; Masi, Silvia; Massardi, Marcella; Matarrese, Sabino; Melchiorri, Alessandro; Melin, Jean-Baptiste; Mennella, Aniello; Mignano, Arturo; Miville-Deschênes, Marc-Antoine; Monfardini, Alessandro; Murphy, Anthony; Naselsky, Pavel; Nati, Federico; Natoli, Paolo; Negrello, Mattia; Noviello, Fabio; O'Sullivan, Créidhe; Paci, Francesco; Pagano, Luca; Paladino, Rosita; Palanque-Delabrouille, Nathalie; Paoletti, Daniela; Peiris, Hiranya; Perrotta, Francesca; Piacentini, Francesco; Piat, Michel; Piccirillo, Lucio; Pisano, Giampaolo; Polenta, Gianluca; Pollo, Agnieszka; Ponthieu, Nicolas; Remazeilles, Mathieu; Ricciardi, Sara; Roman, Matthieu; Rosset, Cyrille; Rubino-Martin, Jose-Alberto; Salatino, Maria; Schillaci, Alessandro; Shellard, Paul; Silk, Joseph; Starobinsky, Alexei; Stompor, Radek; Sunyaev, Rashid; Tartari, Andrea; Terenzi, Luca; Toffolatti, Luigi; Tomasi, Maurizio; Trappe, Neil; Tristram, Matthieu; Trombetti, Tiziana; Tucci, Marco; Van de Weijgaert, Rien; Van Tent, Bartjan; Verde, Licia; Vielva, Patricio; Wandelt, Ben; Watson, Robert; Withington, Stafford

    2014-01-01

    PRISM (Polarized Radiation Imaging and Spectroscopy Mission) was proposed to ESA in May 2013 as a large-class mission for investigating within the framework of the ESA Cosmic Vision program a set of important scientific questions that require high resolution, high sensitivity, full-sky observations

  16. COMET and PRISM - Search for Charged Lepton Flavor Violation with Muons

    Energy Technology Data Exchange (ETDEWEB)

    Kuno, Yoshitaka [Department of Physics, Osaka University, Osaka, 560-0043 (Japan)

    2012-04-15

    The experiment (COMET) at J-PARC to search for a charged-lepton-flavor-violating process of muon to electron conversion in a muonic atom is described. Future prospects of an experiment (PRISM) with even higher sensitivity is mentioned. On-going R and D on a highly intense muon source (MuSIC) at Osaka University is presented.

  17. Active control of flow around a square prism by slot jet injection

    Directory of Open Access Journals (Sweden)

    Hacıalioğulları M.

    2013-04-01

    Full Text Available The main aim of the experimental study is to determine both the most effective injection surface and rate in order to ensure minimum drag and fluctuating forces on a square prism subjected to crossflow. All predetermined jet injection surfaces i.e. front, side, and rear, tested separately for injection ratios of IR = 0, 1, 1.5, 2 at Reynolds number of Re = 16,000. Surface pressures were measured by differential pressure transducer whereas instantaneous velocity measurements were performed by using multichannel Constant Temperature Anemometer (CTA. It was concluded that jet injection, especially from the rear surface, brought noticeable improvements to the flow characteristics of a square prism. For rear jet configuration with IR = 1.5, the mean drag coefficient (CDT¯$overline {{C_{{m{DT}}}}} $ was reduced to 79.4% and CP RMS level on side surfaces was reduced to 20% of that of the single square prism. In addition, instantaneous flow visualization photographs and Strouhal number (St distribution across the injection ratio were also presented to identify the flow patterns and underlying mechanism of drag and fluctuating force reduction of square prism with rear jet configuration.

  18. Epidemiological characteristics of patients with Chagas Disease Características epidemiológicas dos pacientes com Doença de Chagas

    Directory of Open Access Journals (Sweden)

    Fabíola Adriane Souza Oliveira

    2010-11-01

    Full Text Available

    The Chagas Disease is an infection caused by Trypanosoma cruzy, transmitted to a hematophague insect, transfused blood or birth, with evolution divided in acute and chronic phases. Object: Analyses variables from patients with Chagas Disease (CD: age, gender, education, prevalence, and presence of co morbid and work. Methodology: The study region is constituted by many peripheral neighborhoods from Montes Claros City- Minas Gerais- Brazil. The study was made with 7150 registered people in the local health unit (Programa Saúde da Família, Tancredo Neves. The information about Chagas Disease was obtaining from ‘A’ files, this present in virtual information program. Take a part in the study only patients with the confirmed diagnostic of Chagas Disease in two diagnostic methods different. Results: The prevalence of Chagas Disease were 1% (86 patients, 60% of cases belong of female gender. The middle age at the men was 47,5 years and the woman was 48,6 years. The main occupation were: retired 9,3%, general services 51,1%, house-wife 17,4%, unemployment 18,5%, students 1,1% and autonomous 1,1%. The analysis of schooling demonstrates: 27,9% was illiterate, 68,6% does not have completely the primary school and 2,3% has completely the second school. The co morbid more seen were the Systemic Hypertension Arterial (SHA. Conclusion: The epidemiological profile in the study site is of the an adult patient with the age between 40-50 years, female gender, with schooling low, working in general services and with SHA were the co morbid.

    A Doença de Chagas (DC é uma infecção causada pelo Trypanosoma cruzi, transmitida por um inseto hematófago, adquirida por transfusão sanguínea ou congenitamente, com evolução dividida em fase aguda e crônica. Objetivo: Analisar as seguintes variáveis dos pacientes portadores da Doença de Chagas (DC: idade, sexo, escolaridade, prevalência, comorbidades associadas e ocupação. Metodologia: A região do

  19. [A study of the antiherpetic activity of the chaga mushroom (Inonotus obliquus) extracts in the Vero cells infected with the herpes simplex virus].

    Science.gov (United States)

    Polkovnikova, M V; Nosik, N N; Garaev, T M; Kondrashina, N G; Finogenova, M P; Shibnev, V A

    2014-01-01

    The chaga mushroom (Inonotus obliquus) contains a wide range of excellent bioactive compounds. However, limited information exists on the antiviral activity of the compounds extracted from chaga. A number of subfractions of chaga were obtained using different solvents and different procedures. The subfractions of chaga extracted with water, alcohol, alkali were tested for their toxicity for the Vero cell culture and antiviral effect in the Vero cells infected with the Herpes simplex virus (HSV), Type 1. It was shown that most of the subfractions were not toxic for the Vero cells and had protective effect on the Vero cells infected with HSV. The subfraction IV in the concentration 5 microg/ml protected the Vero cells from cytodestructive action of HSV and no viral DNA was detected in infected cells treated with chaga extracts. Best protective effect was observed when compound was added before or within one hour after the Vero cells were infected with HSV. PMID:25069286

  20. Prioritization Risk Integration Simulation Model (PRISM) For Environmental Remediation and Waste Management - 12097

    International Nuclear Information System (INIS)

    The PRISM (Prioritization Risk Integration Simulation Model), a computer model was developed to support the Department of Energy's Office of Environmental Management (DOE-EM) in its mission to clean up the environmental legacy from the Nation's nuclear weapons materials production complex. PRISM provides a comprehensive, fully integrated planning tool that can tie together DOE-EM's projects. It is designed to help DOE managers develop sound, risk-informed business practices and defend program decisions. It provides a better ability to understand and manage programmatic risks. The underlying concept for PRISM is that DOE-EM 'owns' a portfolio of environmental legacy obligations (ELOs), and that its mission is to transform the ELOs from their current conditions to acceptable conditions, in the most effective way possible. There are many types of ELOs - - contaminated soils and groundwater plumes, disused facilities awaiting D and D, and various types of wastes waiting for processing or disposal. For a given suite of planned activities, PRISM simulates the outcomes as they play out over time, allowing for all key identified uncertainties and risk factors. Each contaminated building, land area and waste stream is tracked from cradle to grave, and all of the linkages affecting different waste streams are captured. The progression of the activities is fully dynamic, reflecting DOE-EM's prioritization approaches, precedence requirements, available funding, and the consequences of risks and uncertainties. The top level of PRISM is the end-user interface that allows rapid evaluation of alternative scenarios and viewing the results in a variety of useful ways. PRISM is a fully probabilistic model, allowing the user to specify uncertainties in input data (such as the magnitude of an existing groundwater plume, or the total cost to complete a planned activity) as well as specific risk events that might occur. PRISM is based on the GoldSim software that is widely used for risk

  1. Illusory reversal of causality between touch and vision has no effect on prism adaptation rate

    Directory of Open Access Journals (Sweden)

    Hirokazu eTanaka

    2012-12-01

    Full Text Available Learning, according to Oxford Dictionary, is to gain knowledge or skill by studying, from experience, from being taught, etc. In order to learn from experience, the central nervous system has to decide what action leads to what consequence, and temporal perception plays a critical role in determining the causality between actions and consequences. In motor adaptation, causality between action and consequence is implicitly assumed so that a subject adapts to a new environment based on the consequence caused by her action. Adaptation to visual displacement induced by prisms is a prime example; the visual error signal associated with the motor output contributes to the recovery of accurate reaching, and a delayed feedback of visual error can decrease the adaptation rate. Subjective feeling of temporal order of action and consequence, however, can be modified or even reversed when her sense of simultaneity is manipulated with an artificially delayed feedback. Our previous study (Tanaka, Homma & Imamizu (2011 Exp Brain Res demonstrated that the rate of prism adaptation was unaffected when the subjective delay of visual feedback was shortened. This study asked whether subjects could adapt to prism adaptation and whether the rate of prism adaptation was affected when the subjective temporal order was illusory reversed. Adapting to additional 100 ms delay and its sudden removal caused a positive shift of point of simultaneity in a temporal-order judgment experiment, indicating an illusory reversal of action and consequence. We found that, even in this case, the subjects were able to adapt to prism displacement with the learning rate that was statistically indistinguishable to that without temporal adaptation. This result provides further evidence to the dissociation between conscious temporal perception and motor adaptation.

  2. Preapplication safety evaluation report for the Power Reactor Innovative Small Module (PRISM) liquid-metal reactor

    International Nuclear Information System (INIS)

    This preapplication safety evaluation report (PSER) presents the results of the preapplication desip review for die Power Reactor Innovative Small Module (PRISM) liquid-mew (sodium)-cooled reactor, Nuclear Regulatory Commission (NRC) Project No. 674. The PRISM conceptual desip was submitted by the US Department of Energy in accordance with the NRC's ''Statement of Policy for the Regulation of Advanced Nuclear Power Plants'' (51 Federal Register 24643). This policy provides for the early Commission review and interaction with designers and licensees. The PRISM reactor desip is a small, modular, pool-type, liquid-mew (sodium)-cooled reactor. The standard plant design consists of dim identical power blocks with a total electrical output rating of 1395 MWe- Each power block comprises three reactor modules, each with a thermal rating of 471 MWt. Each module is located in its own below-grade silo and is co to its own intermediate heat transport system and steam generator system. The reactors utilize a metallic-type fuel, a ternary alloy of U-Pu-Zr. The design includes passive reactor shutdown and passive decay heat removal features. The PSER is the NRC's preliminary evaluation of the safety features in the PRISM design, including the projected research and development programs required to support the design and the proposed testing needs. Because the NRC review was based on a conceptual design, the PSER did not result in an approval of the design. Instead it identified certain key safety issues, provided some guidance on applicable licensing criteria, assessed the adequacy of the preapplicant's research and development programs, and concluded that no obvious impediments to licensing the PRISM design had been identified

  3. Design considerations for an unconventional infrared prism with a 90-degree ray deviation

    Science.gov (United States)

    Akarca, Beyza; Artan, Göktuǧ G.

    2015-09-01

    In this study, the optical performance of a 90 degree prism working in the mid-wave infrared region with the purpose of carrying a beam of light from one optical system to another in an unconventional way is discussed. First, a group of mirrors is considered as a design alternative to lower the overall cost of the system. However, using mirrors greatly increases the diameter of the beam due to the rays coming from wide field of view angles. Another drawback of mirrors is that having separate mirrors requires precise alignment for the system to work at full performance which is difficult for the given application. However, these alignment issues are not valid for a single piece prism. Therefore, a single piece prism is the preferred option and has been taken into account in this study. Material selection is important, especially in the mid-wave infrared region where the index of refraction differs greatly from material to material. Silicon and Germanium are the materials preferred because of their high index of refraction and transmission characteristics. Aside from optical properties, these materials are also considered in terms of manufacturability. Also, options for the coatings to be applied to reflecting surfaces of the prism are discussed with regard to the transmission loss within the system. In order to have total internal reflection within a prism, coatings must be chosen carefully to handle transmission loss at the reflecting surfaces. All of the system parameters are examined using sequential and non-sequential modes of ZEMAX OpticStudio software.

  4. The Personalized Reminder Information and Social Management System (PRISM) Trial: Rationale, Methods and Baseline Characteristics

    Science.gov (United States)

    Czaja, Sara J.; Boot, Walter R.; Charness, Neil; Rogers, Wendy; Sharit, Joseph; Fisk, Arthur D.; Lee, Chin Chin; Nair, Sankaran N.

    2014-01-01

    Technology holds promise in terms of providing support to older adults. To date there have been limited robust systematic efforts to evaluate the psychosocial benefits of technology for older people and identify factors that influence both the usability and uptake of technology systems. In response to these issues we developed the Personal Reminder Information and Social Management System (PRISM), a software application designed for older adults to support social connectivity, memory, knowledge about topics, leisure activities and access to resources. This trail is evaluating the impact of access to the PRISM system on outcomes such as social isolation, social support and connectivity. This paper reports on the approach used to design the PRISM system, study design, methodology and baseline data for the trial. The trial is multi-site randomized field trial. PRISM is being compared to a Binder condition where participants received a binder that contained content similar to that found on PRISM. The sample includes 300 older adults, aged 65 – 98 years, who lived alone and at risk for being isolated. The primary outcome measures for the trial include indices of social isolation and support and well-being. Secondary outcomes measures include indices of computer proficiency, technology uptake and attitudes towards technology. Follow-up assessments occurred at 6 and 12 months post-randomization. The results of this study will yield important information about the potential value of technology for older adults. The study also demonstrates how a user-centered iterative design approach can be incorporated into the design and evaluation of an intervention protocol. PMID:25460342

  5. Testing the PRISM Temperature Model in Complex Terrain: Implications for Mountain Ecohydrology

    Science.gov (United States)

    Strachan, S.; Daly, C.; Millar, C.

    2015-12-01

    Studies in mountainous terrain related to ecology and hydrology often use interpolated climate products because of a lack of local observations. One dataset frequently used to develop plot-to-watershed scale climatologies is the PRISM (Parameter-elevation Regression on Independent Slopes Model) temperature model. Benefits of this approach include geographically-weighted station observations and topographic positioning modifiers, which become important factors for predicting temperature in complex topography. Because of the paucity of long-term climate records in mountain environments, validation of PRISM algorithms across diverse regions remains challenging, with end users instead relying on atmospheric relationships derived in sometimes distant geographic settings. Recent developments of the PRISM model have increased temporal resolution capability from monthly to daily, which in turn has allowed a reasonable test of PRISM performance during a single season at distributed points across a large watershed. Presented are results from testing instrumental observations of daily max/min temperature on 16 sites in the Walker Basin, CA-NV, located on open woodland slopes ranging from 1967 to 3111 m in elevation. Individual site MAE varies from 1.34 to 4.22 C with better performance observed during summertime as opposed to winter. We observe a consistent bias in minimum temperatures for all seasons across all sites, with bias in maximum temperatures varying with season. Model error for minimum is associated strongly with elevation, whereas model error for maximum is associated with topographic radiative indices (solar exposure and heat loading). These results indicate that actual temperature conditions across open mountain woodland slopes are more heterogeneous than interpolated models (such as PRISM) indicate, which in turn impacts prediction/modeling of landscape processes such as ecological niches, bioclimatic refugia, and snow hydrology.

  6. Seroprevalence and sociocultural conditionants of Chagas disease in school aged children of marginal zones of Asunción

    Directory of Open Access Journals (Sweden)

    Vera Ninfa I.

    1998-01-01

    Full Text Available Chagas disease is becoming a public health problem in Latin America due to the wide distribution, the high prevalence, the magnitude of the damage caused and the difficulties to control it. In Paraguay, the disease is mainly distributed in the departments of Paraguari, Cordillera and Central. Prevalence in marginal zones, where migrations from rural populations and endemic areas make possible the urbanization of the disease, has no been studied yet. This is a descriptive study with a cross-sectional sampling and a probabilistic system recruitment carried out in school aged children from marginal zones of Asuncion to determine the prevalence of Chagas' disease. Serological methods, parasite isolation and questionnaires were used to achieve the goals. Nine hundred and fifty three children were studied to determine the prevalence of Chagas' disease in marginal zones which was 1.4%.

  7. Synthesis of hexagonal wurtzite Cu2ZnSnS4 prisms by an ultrasound-assisted microwave solvothermal method

    International Nuclear Information System (INIS)

    Wurtzite Cu2ZnSnS4 (CZTS) hexagonal prisms were synthesized by a simple ultrasound-microwave solvothermal method. The product was characterized by XRD, FESEM, EDS, TEM, Raman and UV–vis spectrometer. The hexagonal prisms were 0.5–2 μm wide and 5–12 μm long. The PVP played an important role in the formation of the CZTS hexagonal prisms. In addition, the ultrasound-assisted microwave process was helpful for synthesis of wurtzite rather than kesterite phase CZTS. A nucleation–dissolution–recrystallization mechanism was also proposed to explain the growth of the CZTS hexagonal prisms. - Graphical abstract: Wurtzite Cu2ZnSnS4 hexagonal prisms were synthesized by ultrasound-microwave solvothermal method. The ultrasound-assisted microwave process and PVP were useful to the growth of CZTS. A nucleation–dissolution–recrystallization growth mechanism was also proposed. - Highlights: • Wurtzite Cu2ZnSnS4 was prepared by ultrasound-assisted microwave solvothermal method. • The wurtzite CZTS hexagonal prisms are demonstrated a band gap of 1.49 eV. • Synergistic effect of ultrasound and microwave is helpful to prepare Wurtzite CZTS. • PVP plays an important role in the formation of the CZTS hexagonal prisms. • Nucleation–dissolution–recrystallization growth mechanism of the CZTS was proposed

  8. Protective human leucocyte antigen haplotype, HLA-DRB1*01-B*14, against chronic Chagas disease in Bolivia.

    Directory of Open Access Journals (Sweden)

    Florencia del Puerto

    Full Text Available BACKGROUND: Chagas disease, caused by the flagellate parasite Trypanosoma cruzi affects 8-10 million people in Latin America. The mechanisms that underlie the development of complications of chronic Chagas disease, characterized primarily by pathology of the heart and digestive system, are not currently understood. To identify possible host genetic factors that may influence the clinical course of Chagas disease, Human Leucocyte Antigen (HLA regional gene polymorphism was analyzed in patients presenting with differing clinical symptoms. METHODOLOGY: Two hundred and twenty nine chronic Chagas disease patients in Santa Cruz, Bolivia, were examined by serological tests, electrocardiogram (ECG, and Barium enema colon X-ray. 31.4% of the examinees showed ECG alterations, 15.7% megacolon and 58.1% showed neither of them. A further 62 seropositive megacolon patients who had undergone colonectomy due to acute abdomen were recruited. We analyzed their HLA genetic polymorphisms (HLA-A, HLA-B, MICA, MICB, DRB1 and TNF-alpha promoter region mainly through Sequence based and LABType SSO typing test using LUMINEX Technology. PRINCIPAL FINDINGS: The frequencies of HLA-DRB1*01 and HLA-B*14:02 were significantly lower in patients suffering from megacolon as well as in those with ECG alteration and/or megacolon compared with a group of patients with indeterminate symptoms. The DRB1*0102, B*1402 and MICA*011 alleles were in strong Linkage Disequilibrium (LD, and the HLA-DRB1*01-B*14-MICA*011 haplotype was associated with resistance against chronic Chagas disease. CONCLUSIONS: This is the first report of HLA haplotype association with resistance to chronic Chagas disease.

  9. Evaluation of the Chagas Disease Control Program in Açucena Municipality, Rio Doce Valley, State of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Adriana dos Santos

    2014-04-01

    Full Text Available Introduction Açucena Municipality, Rio Doce Valley, State of Minas Gerais, Brazil temporarily (2001-2005 interrupted epidemiological surveillance for Chagas disease. The objective of this work was to evaluate the Chagas Disease Control Program (CDCP in Açucena and to offer suggestions for improving local epidemiological surveillance. Methods This study was conducted in three phases: I a serological investigation of schoolchildren aged 5 to 15 years using an enzyme-linked immunosorbent assay (ELISA test performed on blood collected on filter paper followed by ELISA, indirect immunofluorescence (IIF and indirect hemaglutination (IHA on venous blood for borderline cases and those in the gray zone of reactivity; II vector evaluation using the data obtained by local health agents during 2006-2010; and III examination by ELISA, IIF and IHA of serum samples from the inhabitants of houses where infected Triatoma vitticeps was found and evaluation of their knowledge about Chagas disease. Results Five individuals had inconclusive results in the ELISA screening but were seronegative for Chagas disease. The triatomine evaluation revealed the presence of three species: Triatoma vitticeps, Panstrongylus megistus and Panstrongylus diasi. Triatoma vitticeps was the most prevalent and widespread, with a higher (67% index of Trypanosoma cruzi flagellates and evidence of colonization. Most of the inhabitants of the infested houses recognized triatomines and had basic knowledge about Chagas disease. Conclusions Although T. vitticeps is not clearly associated with Chagas disease transmission, these results highlight the importance of maintaining CDCP in endemic areas and the need for greater emphasis on epidemiological surveillance, especially in areas with important vectorial changes or that have been modified by human intervention.

  10. Prevalence, clinical staging and risk for blood-borne transmission of Chagas disease among Latin American migrants in Geneva, Switzerland.

    Directory of Open Access Journals (Sweden)

    Yves Jackson

    Full Text Available BACKGROUND: Migration of Latin Americans to the USA, Canada and Europe has modified Chagas disease distribution, but data on imported cases and on risks of local transmission remain scarce. We assessed the prevalence and risk factors for Chagas disease, staged the disease and evaluated attitudes towards blood transfusion and organ transplant among Latin American migrants in Geneva, Switzerland. METHODOLOGY/PRINCIPAL FINDINGS: This cross-sectional study included all consecutive Latin American migrants seeking medical care at a primary care facility or attending two Latino churches. After completing a questionnaire, they were screened for Chagas disease with two serological tests (Biomérieux ELISA cruzi; Biokit Bioelisa Chagas. Infected subjects underwent a complete medical work-up. Predictive factors for infection were assessed by univariate and multivariate logistic regression analysis.1012 persons (females: 83%; mean age: 37.2 [SD 11.3] years, Bolivians: 48% [n = 485] were recruited. 96% had no residency permit. Chagas disease was diagnosed with two positive serological tests in 130 patients (12.8%; 95%CI 10.8%-14.9%, including 127 Bolivians (26.2%; 95%CI 22.3%-30.1%. All patients were in the chronic phase, including 11.3% with cardiac and 0.8% with digestive complications. Predictive factors for infection were Bolivian origin (OR 33.2; 95%CI 7.5-147.5, reported maternal infection with T. cruzi (OR 6.9; 95%CI 1.9-24.3, and age older than 35 years (OR 6.7; 95%CI 2.4-18.8. While 22 (16.9% infected subjects had already donated blood, 24 (18.5% and 34 (26.2% considered donating blood and organs outside Latin America, respectively. CONCLUSIONS: Chagas disease is highly prevalent among Bolivian migrants in Switzerland. Chronic cardiac and digestive complications were substantial. Screening of individuals at risk should be implemented in nonendemic countries and must include undocumented migrants.

  11. Carlos Chagas Filho: um articulador da história das ciências do Brasil Carlos Chagas Filho: an articulator of the history of sciences in Brazil

    OpenAIRE

    Heloisa Maria Bertol Domingues

    2012-01-01

    Uma carta enviada em 1982 por um grupo de cientistas ao presidente do Conselho Nacional de Desenvolvimento Científico e Tecnológico reivindicava uma política de preservação da cultura científica brasileira. O nome Carlos Chagas Filho encabeçava a lista de assinaturas, a mostrar seu engajamento naquela proposta, cuja estrutura ideológica fez parte da sua vivência na política científica, no Brasil e no exterior. Esse documento remete à prática da história das ciências no Brasil e à criação de l...

  12. Pneumonia lipoídica associada à forma digestiva da doença de Chagas Digestive Chagas disease with concomitant lipoid pneumonia

    OpenAIRE

    Marcelo Fernando Ranzani; Nilson Sebastião Miranda; Ulisses Frederigue Junior; Sérgio Marrone Ribeiro; Jussara Marcondes Machado

    2004-01-01

    Mulher de 50 anos com megaesôfago e megacólon chagásico apresentou quadro clínico de tosse seca, dor torácica e dispnéia leves. O raio X de tórax mostrou opacidade do tipo alveolar bilateral sugestivo de pneumonia. Após biópsia a céu aberto chegou-se ao diagnóstico de pneumonia lipoídica. A doença foi causada pelo uso crônico de laxantes à base de óleo mineral, utilizados nos últimos três anos. Os autores discutem a associação da forma digestiva da doença de Chagas com pneumonia lipoídica, e ...

  13. Serological survey for Chagas' disease in school children in the Rio de Janeiro State, Brazil

    Directory of Open Access Journals (Sweden)

    Walter B. Petana

    1976-04-01

    Full Text Available A serological survey for Chagas' disease was carried out in school children in the Rio de Janeiro State, a zone considered as non-endemic for the infection. A total of 168 schools in 20 municipalities have been visited and 13,254 blood samples were obtained. The blood eluates were screened by the indirect fluorescence test (IFT, and all positive samples were checked and confirmed in sera by the complement fixation test (CFT. AH serologically positive children were subject to a clinical scrutiny, and the houses where the children lived have been searched for triatomine bugs. Only in two municipalities, Magé and Araruama, there was a significant number of children found positive. The total number of reactive samples by IFT and CFT from 13,004 blood samples screened was 143 (1.00 per cent. No serious clinicai symptoms suggestive of Chagas' disease have been found in any of the positive children, and no triatomine bugs were discovered in the dwellings where the children lived. The overall small percentage of children with positive serology postulates that the infection is not a serious health problem in the area investigated. It is recommended, however, to carry out a more detailed study in Magé and Araruama to find the reason for the relatively high percentage of serologically positive children encountered in these two municipalities.Um inquérito sorológico pela reação de imunofluorescência indireta para doença de Chagas, foi realizado, incluindo 13.254 crianças de 168 escolas primárias sorteadas em 20 municípios do Estado do Rio de Janeiro. Os casos positivos pela imunofluorescência eram confirmados pela reação de fixação do complemento e submetidos a exame clínico, investigando-se em seguida suas residências quanto à existência ou não de triatomíneos. Somente nos municípios de Magé e Araruama houve um número significativo de crianças com sorologia positiva. Do total de amostras estudadas somente 143 (1% foram positivas

  14. When a Diplomat goes into politics because of war. The case of João Chagas (1910-1914

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    Luís Alves de Fraga

    2012-01-01

    Full Text Available Analysis of the case of a Portuguese diplomat, João Chagas, who, during the First Republic, and by resorting to the conditions available to him as representative of his country, surpassed the mere negotiating role attributed to diplomacy to conduct national politics, succeeding in changing the international statute of Portugal in the Great War. The article describes the internal and external situation of Portugal in political, geopolitical and geostrategic terms, the conflict between Portuguese and British interests, the activity of Portuguese diplomats in London, Berlin and Paris, and, finally, the work of João Chagas.

  15. Los domingos del mes del Chagas en el Museo de La Plata 2012 : Conociendo a nuestros visitantes

    OpenAIRE

    Scazzola, María Soledad; Ceccarelli, Soledad; Reche, Vanina Anadina; Sanmartino, Mariana; Mordeglia, Cecilia; Amieva, Carolina

    2013-01-01

    En este trabajo compartimos el análisis de algunos de los resultados obtenidos a partir de las actividades desarrolladas durante los fines de semana de agosto en el Museo de La Plata (Buenos Aires). Éstas se enmarcaron en el “Mes del Chagas 2012”, organizado por el Proyecto de Extensión Universitaria “¿De qué hablamos cuando hablamos de Chagas? Estrategias y recursos didácticos para abordar el tema en diferentes contextos educativos” (Universidad Nacional de La Plata). Más de 6000 personas co...

  16. Current epidemiological trends for Chagas disease in Latin America and future challenges in epidemiology, surveillance and health policy

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    Álvaro Moncayo

    2009-07-01

    Full Text Available Chagas disease, named after Carlos Chagas, who first described it in 1909, exists only on the American Continent. It is caused by a parasite, Trypanosoma cruzi, which is transmitted to humans by blood-sucking triatomine bugs and via blood transfusion. Chagas disease has two successive phases: acute and chronic. The acute phase lasts six-eight weeks. Several years after entering the chronic phase, 20-35% of infected individuals, depending on the geographical area, will develop irreversible lesions of the autonomous nervous system in the heart, oesophagus and colon, and of the peripheral nervous system. Data on the prevalence and distribution of Chagas disease improved in quality during the 1980s as a result of the demographically representative cross-sectional studies in countries where accurate information was not previously available. A group of experts met in Brasilia in 1979 and devised standard protocols to carry out countrywide prevalence studies on human T. cruzi infection and triatomine house infestation. Thanks to a coordinated multi-country programme in the Southern Cone countries, the transmission of Chagas disease by vectors and via blood transfusion was interrupted in Uruguay in 1997, in Chile in 1999 and in Brazil in 2006; thus, the incidence of new infections by T. cruzi across the South American continent has decreased by 70%. Similar multi-country initiatives have been launched in the Andean countries and in Central America and rapid progress has been reported towards the goal of interrupting the transmission of Chagas disease, as requested by a 1998 Resolution of the World Health Assembly. The cost-benefit analysis of investment in the vector control programme in Brazil indicates that there are savings of US$17 in medical care and disabilities for each dollar spent on prevention, showing that the programme is a health investment with very high return. Many well-known research institutions in Latin America were key elements of a

  17. Eu3+-doped Y2O3 hexagonal prisms: Shape-controlled synthesis and tailored luminescence properties

    International Nuclear Information System (INIS)

    In this work, Eu3+ doped Y2O3 hexagonal prisms were synthesized by a novel two-phase approach, which involves water at the bottom as aqueous phase and oleylamine in the above as oil phase. With this unique reaction system, precursors of hexagonal prisms Y4O(OH)9(NO3) were first obtained by simply varying the volume ratio of water to oleylamine. Time-dependent experiments were systematically performed to reveal the growth mechanism of the precursor. After subsequent heat treatment, these precursors transformed to Y2O3 hexagonal prisms with controlled diameters and aspect ratios varying from 4 to 19. Such a transformation is preceded via a topotactic process, as indicated by TG-DTA and mass spectra. Eventually, all Eu3+ doped Y2O3 hexagonal prisms were found to exhibit an intensive red emission at 611 nm, which corresponds to 5D0→7F2 transition of Eu3+. With varying the aspect ratio of hexagonal prisms and increasing Eu3+ concentration in Y2O3, an optimum external quantum efficiency was achieved. - Graphical abstract: In this work, Eu3+ doped Y2O3 hexagonal prisms with controlled aspect ratio from 4.4 to 19.3 were synthesized by transformation of the precursor Y4O(OH)9(NO3) hexagonal prisms from a novel two-phase reaction system. The growth mechanism of the precursor has been systematically investigated, and a topotactic phase transformation from precursors to cubic Y2O3 is for the first time put forward. By the size controlling and aspect ratio adjusting, the luminescence emission intensity as well as external quantum efficiency of Eu3+ doped Y2O3 hexagonal prisms is further tailored to show an optimum. - Highlights: • Eu3+ doped Y2O3 hexagonal prisms were synthesized by a novel two-phase approach. • Inheriting mechanism of prisms morphology from Y4O(OH)9(NO3) to Y2O3 was discussed. • Aspect ratio of prisms was tailored by the volume ratio of water to oleylamine. • Luminescence properties were optimized by adjusting aspect ratio of prisms

  18. Prism stacking faults observed contiguous to a {10-12} twin in a Mg–Y alloy

    International Nuclear Information System (INIS)

    Using transmission electron microscopy, we document, for the first time, the presence of stacking faults on the (10-10) prism planes in a fine-grained Mg–Y alloy. These prism stacking faults were found to be exclusively contiguous to a {10-12} deformation twin. In addition, the {10-12} twin contained a high density of basal plane stacking faults. Arguments are developed for the interrelationship between the stacking faults on the prism planes in the matrix and those on the basal planes in the twin

  19. A poly(dimethylsiloxane) based prism for surface plasmon resonance imaging system and its application for gas detection

    Science.gov (United States)

    Zhang, L. L.; Chen, X.; Sun, J. H.; Cai, H. Y.; Li, H.; Chao, Y. P.; Cui, D. F.

    2013-03-01

    This paper presents a surface plasmon resonance (SPR) imaging system based on a low-cost, convenient poly(dimethylsiloxane) (PDMS) prism featured with a close contact with the gold film. Compared to conventional glass prism, both numerical simulations and experimental studies indicated a deeper but wider absorption peak with a higher coupling angle for the PDMS based prism. System repeatability was quantified by the cycled detection of helium and air, with the effect of the flow rate investigated. Furthermore, five types of gases (nitrogen, air, oxygen, hydrogen, and helium) were detected and differentiated by the SPR system, with a calculated sensitivity of 5 × 10-6 RIU.

  20. Treatment with Benznidazole during the Chronic Phase of Experimental Chagas' Disease Decreases Cardiac Alterations

    Science.gov (United States)

    Garcia, Simone; Ramos, Carolina O.; Senra, Juliana F. V.; Vilas-Boas, Fabio; Rodrigues, Maurício M.; Campos-de-Carvalho, Antonio C.; Ribeiro-dos-Santos, Ricardo; Soares, Milena B. P.

    2005-01-01

    Chagas' disease, caused by Trypanosoma cruzi infection, is one of the main causes of death due to heart failure in Latin American countries. Benznidazole, the chemotherapeutic agent most often used for the treatment of chagasic patients, is highly toxic and has limited efficacy, especially in the chronic phase of the disease. In the present study we used a mouse model of chronic Chagas' disease to investigate the effects of benznidazole treatment during the chronic phase on disease progression. The hearts of benznidazole-treated mice had decreased parasitism and myocarditis compared to the hearts of untreated chagasic mice. Both groups of Trypanosoma cruzi-infected mice had significant alterations in their electrocardiograms compared to those of the healthy mice. However, untreated mice had significantly higher cardiac conduction disturbances than benznidazole-treated mice, including intraventricular conduction disturbances, atrioventricular blocks, and extrasystoles. The levels of antibodies against T. cruzi antigens (epimastigote extract, P2β, and trans-sialidase) as well as antibodies against peptides of the second extracellular loops of β1-adrenergic and M2-muscarinic cardiac receptors were also lower in the sera from benznidazole-treated mice than in the sera from untreated mice. These results demonstrate that treatment with benznidazole in the chronic phase of infection prevents the development of severe chronic cardiomyopathy, despite the lack of complete parasite eradication. In addition, our data highlight the role of parasite persistence in the development of chronic Chagas' disease and reinforce the importance of T. cruzi elimination in order to decrease or prevent the development of severe chagasic cardiomyopathy. PMID:15793134

  1. Relationship between Fibrosis and Ventricular Arrhythmias in Chagas Heart Disease Without Ventricular Dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Tassi, Eduardo Marinho, E-mail: etassi@ibest.com.br [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Continentino, Marcelo Abramoff [Hospital Frei Galvão, Guaratinguetá, SP (Brazil); Nascimento, Emília Matos do; Pereira, Basílio de Bragança [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Coppe - Instituto Alberto Luiz Coimbra de Pós-Graduação e Pesquisa de Engenharia - UFRJ, Rio de Janeiro, RJ (Brazil); Pedrosa, Roberto Coury [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

    2014-05-15

    Patients with Chagas disease and segmental wall motion abnormality (SWMA) have worse prognosis independent of left ventricular ejection fraction (LVEF). Cardiac magnetic resonance (CMR) is currently the best method to detect SWMA and to assess fibrosis. To quantify fibrosis by using late gadolinium enhancement CMR in patients with Chagas disease and preserved or minimally impaired ventricular function (> 45%), and to detect patterns of dependence between fibrosis, SWMA and LVEF in the presence of ventricular arrhythmia. Electrocardiogram, treadmill exercise test, Holter and CMR were carried out in 61 patients, who were divided into three groups as follows: (1) normal electrocardiogram and CMR without SWMA; (2) abnormal electrocardiogram and CMR without SWMA; (3) CMR with SWMA independently of electrocardiogram. The number of patients with ventricular arrhythmia in relation to the total of patients, the percentage of fibrosis, and the LVEF were, respectively: Group 1, 4/26, 0.74% and 74.34%; Group 2, 4/16, 3.96% and 68.5%; and Group 3, 11/19, 14.07% and 55.59%. Ventricular arrhythmia was found in 31.1% of the patients. Those with and without ventricular arrhythmia had mean LVEF of 59.87% and 70.18%, respectively, and fibrosis percentage of 11.03% and 3.01%, respectively. Of the variables SWMA, groups, age, LVEF and fibrosis, only the latter was significant for the presence of ventricular arrhythmia, with a cutoff point of 11.78% for fibrosis mass (p < 0.001). Even in patients with Chagas disease and preserved or minimally impaired ventricular function, electrical instability can be present. Regarding the presence of ventricular arrhythmia, fibrosis is the most important variable, its amount being proportional to the complexity of the groups.

  2. Stairway to Heaven or Hell? Perspectives and Limitations of Chagas Disease Chemotherapy.

    Science.gov (United States)

    Salomao, Kelly; Menna-Barreto, Rubem Figueiredo Sadok; de Castro, Solange Lisboa

    2016-01-01

    In this review, we intend to provide a general view of the evolution of experimental studies in the area of chemotherapy for Chagas disease. We can follow the process of drug development through three phases. The first phase began almost at the same time as the discovery made by Carlos Chagas and proceeds to 1970, during which time an extensive list of compounds was subjected to preclinical and clinical trials. The second phase began with the introduction of nifurtimox and benznidazole into the clinical setting, followed with the search for alternative drugs. In this phase, a dichotomy existed between rational and empirical approaches in preclinical studies. The third phase began with the unravelling of the T. cruzi genome. The development of transgenic parasites has allowed the development of solid HTS protocols, and the establishment of bioluminescent T. cruzi has allowed in vivo drug evaluations using a reduced number of animals. Among the wide variety of compounds subjected to preclinical studies, we have discovered azolic and non-azolic inhibitors of sterol C14α-demethylase (CYP51) and nitro compounds. Two compounds evaluated during the second phase, namely, MK-436 and allopurinol, could be revisited. Clinical studies of posaconazole and E1224 yielded disappointing results, and it is critical to understand the reason for their failure as a monotherapy. Currently, the combination and repositioning of drugs with different mechanisms of action are complementary approaches. The use of drug combinations, particularly those of nitro compounds with CYP51 inhibitors, is considered a real alternative for the treatment of Chagas disease.

  3. Integrate Study of a Bolivian Population Infected by Trypanosoma cruzi, the Agent of Chagas Disease

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    Simone Frédérique Brenière

    2002-04-01

    Full Text Available A cross section of a human population (501 individuals selected at random, and living in a Bolivian community, highly endemic for Chagas disease, was investigated combining together clinical, parasitological and molecular approaches. Conventional serology and polymerase chain reaction (PCR indicated an active transmission of the infection, a high seroprevalence (43.3% ranging from around 12% in 45 years, and a high sensitivity (83.8% and specificity of PCR. Abnormal ECG tracing was predominant in chagasic patients and was already present among individuals younger than 13 years. SAPA (shed acute phase antigen recombinant protein and the synthetic peptide R-13 were used as antigens in ELISA tests. The reactivity of SAPA was strongly associated to Trypanosoma cruzi infection and independent of the age of the patients but was not suitable neither for universal serodiagnosis nor for discrimination of specific phases of Chagas infection. Anti-R-13 response was observed in 27.5% only in chagasic patients. Moreover, anti-R13 reactivity was associated with early infection and not to cardiac pathology. This result questioned previous studies, which considered the anti-R-13 response as a marker of chronic Chagas heart disease. The major clonets 20 and 39 (belonging to Trypanosoma cruzi I and T. cruzi II respectively which circulate in equal proportions in vectors of the studied area, were identified in patients' blood by PCR. Clonet 39 was selected over clonet 20 in the circulation whatever the age of the patient. The only factor related to strain detected in patients' blood, was the anti-R-13 reactivity: 37% of the patients infected by clonet 39 (94 cases had anti-R13 antibodies contrasting with only 6% of the patients without clonet 39 (16 cases.

  4. Design or screening of drugs for the treatment of Chagas disease: what shows the most promise?

    Science.gov (United States)

    Lepesheva, Galina I.

    2013-01-01

    Introduction Endemic in Latin America, Chagas disease is now becoming a serious global health problem, and yet has no financial viability for the pharmaceutical industry and remains incurable. In 2012, two antimycotic drugs inhibitors of fungal sterol 14α-demethylase (CYP51) – posaconazole and ravuconazole – entered clinical trials. Availability of the X-ray structure of the orthologous enzyme from the causative agent of the disease, protozoan parasite Trypanosoma cruzi, determined in complexes with posaconazole as well as with several experimental protozoa-specific CYP51 inhibitors opens an excellent opportunity to improve the situation. Areas covered This article summarizes the information available in PubMed and Google on the outcomes of treatment of the chronic Chagas disease. It also outlines the major features of the T. cruzi CYP51 structure and the possible structure-based strategies for rational design of novel T. cruzi specific drugs. Expert opinion There is no doubt that screenings for alternative drug-like molecules as well as mining the T. cruzi genome for novel drug targets are of great value and might eventually lead to groundbreaking discoveries. However, all newly identified molecules must proceed through the long, expensive and low-yielding drug optimization process, and all novel potential drug targets must be validated in terms of their essentiality and druggability. CYP51 is already a well-validated and highly successful target for clinical and agricultural antifungals. With minimal investments into the final stages of their development/trials, T. cruzi-specific CYP51 inhibitors can provide an immediate treatment for Chagas disease, either on their own or in combination with the currently available drugs. PMID:24079515

  5. Cultivation-independent methods reveal differences among bacterial gut microbiota in triatomine vectors of Chagas disease.

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    Fabio Faria da Mota

    Full Text Available BACKGROUND: Chagas disease is a trypanosomiasis whose agent is the protozoan parasite Trypanosoma cruzi, which is transmitted to humans by hematophagous bugs known as triatomines. Even though insecticide treatments allow effective control of these bugs in most Latin American countries where Chagas disease is endemic, the disease still affects a large proportion of the population of South America. The features of the disease in humans have been extensively studied, and the genome of the parasite has been sequenced, but no effective drug is yet available to treat Chagas disease. The digestive tract of the insect vectors in which T. cruzi develops has been much less well investigated than blood from its human hosts and constitutes a dynamic environment with very different conditions. Thus, we investigated the composition of the predominant bacterial species of the microbiota in insect vectors from Rhodnius, Triatoma, Panstrongylus and Dipetalogaster genera. METHODOLOGY/PRINCIPAL FINDINGS: Microbiota of triatomine guts were investigated using cultivation-independent methods, i.e., phylogenetic analysis of 16s rDNA using denaturing gradient gel electrophoresis (DGGE and cloned-based sequencing. The Chao index showed that the diversity of bacterial species in triatomine guts is low, comprising fewer than 20 predominant species, and that these species vary between insect species. The analyses showed that Serratia predominates in Rhodnius, Arsenophonus predominates in Triatoma and Panstrongylus, while Candidatus Rohrkolberia predominates in Dipetalogaster. CONCLUSIONS/SIGNIFICANCE: The microbiota of triatomine guts represents one of the factors that may interfere with T. cruzi transmission and virulence in humans. The knowledge of its composition according to insect species is important for designing measures of biological control for T. cruzi. We found that the predominant species of the bacterial microbiota in triatomines form a group of low

  6. Amazonian Triatomine Biodiversity and the Transmission of Chagas Disease in French Guiana: In Medio Stat Sanitas.

    Science.gov (United States)

    Péneau, Julie; Nguyen, Anne; Flores-Ferrer, Alheli; Blanchet, Denis; Gourbière, Sébastien

    2016-02-01

    The effects of biodiversity on the transmission of infectious diseases now stand as a cornerstone of many public health policies. The upper Amazonia and Guyana shield are hot-spots of biodiversity that offer genuine opportunities to explore the relationship between the risk of transmission of Chagas disease and the diversity of its triatomine vectors. Over 730 triatomines were light-trapped in four geomorphological landscapes shaping French-Guiana, and we determined their taxonomic status and infection by Trypanosoma cruzi. We used a model selection approach to unravel the spatial and temporal variations in species abundance, diversity and infection. The vector community in French-Guiana is typically made of one key species (Panstrongylus geniculatus) that is more abundant than three secondary species combined (Rhodnius pictipes, Panstrongylus lignarius and Eratyrus mucronatus), and four other species that complete the assemblage. Although the overall abundance of adult triatomines does not vary across French-Guiana, their diversity increases along a coastal-inland gradient. These variations unravelled a non-monotonic relationship between vector biodiversity and the risk of transmission of Chagas disease, so that intermediate biodiversity levels are associated with the lowest risks. We also observed biannual variations in triatomine abundance, representing the first report of a biannual pattern in the risk of Chagas disease transmission. Those variations were highly and negatively correlated with the average monthly rainfall. We discuss the implications of these patterns for the transmission of T. cruzi by assemblages of triatomine species, and for the dual challenge of controlling Amazonian vector communities that are made of both highly diverse and mostly intrusive species.

  7. Stairway to Heaven or Hell? Perspectives and Limitations of Chagas Disease Chemotherapy.

    Science.gov (United States)

    Salomao, Kelly; Menna-Barreto, Rubem Figueiredo Sadok; de Castro, Solange Lisboa

    2016-01-01

    In this review, we intend to provide a general view of the evolution of experimental studies in the area of chemotherapy for Chagas disease. We can follow the process of drug development through three phases. The first phase began almost at the same time as the discovery made by Carlos Chagas and proceeds to 1970, during which time an extensive list of compounds was subjected to preclinical and clinical trials. The second phase began with the introduction of nifurtimox and benznidazole into the clinical setting, followed with the search for alternative drugs. In this phase, a dichotomy existed between rational and empirical approaches in preclinical studies. The third phase began with the unravelling of the T. cruzi genome. The development of transgenic parasites has allowed the development of solid HTS protocols, and the establishment of bioluminescent T. cruzi has allowed in vivo drug evaluations using a reduced number of animals. Among the wide variety of compounds subjected to preclinical studies, we have discovered azolic and non-azolic inhibitors of sterol C14α-demethylase (CYP51) and nitro compounds. Two compounds evaluated during the second phase, namely, MK-436 and allopurinol, could be revisited. Clinical studies of posaconazole and E1224 yielded disappointing results, and it is critical to understand the reason for their failure as a monotherapy. Currently, the combination and repositioning of drugs with different mechanisms of action are complementary approaches. The use of drug combinations, particularly those of nitro compounds with CYP51 inhibitors, is considered a real alternative for the treatment of Chagas disease. PMID:27072716

  8. Antitrypanosomal Treatment with Benznidazole Is Superior to Posaconazole Regimens in Mouse Models of Chagas Disease.

    Science.gov (United States)

    Khare, Shilpi; Liu, Xianzhong; Stinson, Monique; Rivera, Ianne; Groessl, Todd; Tuntland, Tove; Yeh, Vince; Wen, Ben; Molteni, Valentina; Glynne, Richard; Supek, Frantisek

    2015-10-01

    Two CYP51 inhibitors, posaconazole and the ravuconazole prodrug E1224, were recently tested in clinical trials for efficacy in indeterminate Chagas disease. The results from these studies show that both drugs cleared parasites from the blood of infected patients at the end of the treatment but that parasitemia rebounded over the following months. In the current study, we sought to identify a dosing regimen of posaconazole that could permanently clear Trypanosoma cruzi from mice with experimental Chagas disease. Infected mice were treated with posaconazole or benznidazole, an established Chagas disease drug, and parasitological cure was defined as an absence of parasitemia recrudescence after immunosuppression. Twenty-day therapy with benznidazole (10 to 100 mg/kg of body weight/day) resulted in a dose-dependent increase in antiparasitic activity, and the 100-mg/kg regimen effected parasitological cure in all treated mice. In contrast, all mice remained infected after a 25-day treatment with posaconazole at all tested doses (10 to 100 mg/kg/day). Further extension of posaconazole therapy to 40 days resulted in only a marginal improvement of treatment outcome. We also observed similar differences in antiparasitic activity between benznidazole and posaconazole in acute T. cruzi heart infections. While benznidazole induced rapid, dose-dependent reductions in heart parasite burdens, the antiparasitic activity of posaconazole plateaued at low doses (3 to 10 mg/kg/day) despite increasing drug exposure in plasma. These observations are in good agreement with the outcomes of recent phase 2 trials with posaconazole and suggest that the efficacy models combined with the pharmacokinetic analysis employed here will be useful in predicting clinical outcomes of new drug candidates. PMID:26239982

  9. Suicide risk and alcohol and drug abuse in outpatients with HIV infection and Chagas disease

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    Patrícia M. Guimarães

    2014-05-01

    Full Text Available Objective: To evaluate psychiatric comorbidities in outpatients receiving care for HIV and Chagas disease at Instituto de Pesquisa Clínica Evandro Chagas (IPEC, Fundação Oswaldo Cruz (Fiocruz, Rio de Janeiro, Brazil. Methods: Cross-sectional study with a consecutive sample of 125 patients referred to an outpatient psychiatric clinic from February to December 2010. The Mini International Neuropsychiatric Interview (MINI was used. Factors associated with more frequent mental disorders were estimated by odds ratios (OR with 95% confidence intervals (95%CI by multiple logistic regression. Results: Seventy-six (60.8% patients with HIV, 40 (32% patients with Chagas disease, and nine (7.2% patients with human T-lymphotropic virus were interviewed. The majority were women (64%, with up to 8 years of formal education (56%, and unemployed (81.6%. The median age was 49 years. Suicide risk (n=71 (56%, agoraphobia (n=65 (52%, major depressive episode (n=56 (44.8%, and alcohol/drug abuse (n=43 (34.4% predominated, the latter being directly associated with lower family income (OR = 2.64; 95%CI 1.03-6.75 and HIV infection (OR = 5.24; 95%CI 1.56-17.61. Suicide risk was associated with non-white skin color (OR = 2.21; 95%CI 1.03-4.75, unemployment (OR = 2.72; 95%CI 1.01-7.34, and diagnosis of major depression (OR = 3.34; 95%CI 1.54-7.44. Conclusion: Measures targeting adverse socioeconomic conditions and psychiatric and psychological monitoring and care should be encouraged in this population, considering the association with abuse of alcohol/other psychoactive drugs and suicide risk.

  10. Pharmacophore modeling for anti-Chagas drug design using the fragment molecular orbital method.

    Directory of Open Access Journals (Sweden)

    Ryunosuke Yoshino

    Full Text Available Chagas disease, caused by the parasite Trypanosoma cruzi, is a neglected tropical disease that causes severe human health problems. To develop a new chemotherapeutic agent for the treatment of Chagas disease, we predicted a pharmacophore model for T. cruzi dihydroorotate dehydrogenase (TcDHODH by fragment molecular orbital (FMO calculation for orotate, oxonate, and 43 orotate derivatives.Intermolecular interactions in the complexes of TcDHODH with orotate, oxonate, and 43 orotate derivatives were analyzed by FMO calculation at the MP2/6-31G level. The results indicated that the orotate moiety, which is the base fragment of these compounds, interacts with the Lys43, Asn67, and Asn194 residues of TcDHODH and the cofactor flavin mononucleotide (FMN, whereas functional groups introduced at the orotate 5-position strongly interact with the Lys214 residue.FMO-based interaction energy analyses revealed a pharmacophore model for TcDHODH inhibitor. Hydrogen bond acceptor pharmacophores correspond to Lys43 and Lys214, hydrogen bond donor and acceptor pharmacophores correspond to Asn67 and Asn194, and the aromatic ring pharmacophore corresponds to FMN, which shows important characteristics of compounds that inhibit TcDHODH. In addition, the Lys214 residue is not conserved between TcDHODH and human DHODH. Our analysis suggests that these orotate derivatives should preferentially bind to TcDHODH, increasing their selectivity. Our results obtained by pharmacophore modeling provides insight into the structural requirements for the design of TcDHODH inhibitors and their development as new anti-Chagas drugs.

  11. Utilizing Chemical Genomics to Identify Cytochrome b as a Novel Drug Target for Chagas Disease.

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    Shilpi Khare

    2015-07-01

    Full Text Available Unbiased phenotypic screens enable identification of small molecules that inhibit pathogen growth by unanticipated mechanisms. These small molecules can be used as starting points for drug discovery programs that target such mechanisms. A major challenge of the approach is the identification of the cellular targets. Here we report GNF7686, a small molecule inhibitor of Trypanosoma cruzi, the causative agent of Chagas disease, and identification of cytochrome b as its target. Following discovery of GNF7686 in a parasite growth inhibition high throughput screen, we were able to evolve a GNF7686-resistant culture of T. cruzi epimastigotes. Clones from this culture bore a mutation coding for a substitution of leucine by phenylalanine at amino acid position 197 in cytochrome b. Cytochrome b is a component of complex III (cytochrome bc1 in the mitochondrial electron transport chain and catalyzes the transfer of electrons from ubiquinol to cytochrome c by a mechanism that utilizes two distinct catalytic sites, QN and QP. The L197F mutation is located in the QN site and confers resistance to GNF7686 in both parasite cell growth and biochemical cytochrome b assays. Additionally, the mutant cytochrome b confers resistance to antimycin A, another QN site inhibitor, but not to strobilurin or myxothiazol, which target the QP site. GNF7686 represents a promising starting point for Chagas disease drug discovery as it potently inhibits growth of intracellular T. cruzi amastigotes with a half maximal effective concentration (EC50 of 0.15 µM, and is highly specific for T. cruzi cytochrome b. No effect on the mammalian respiratory chain or mammalian cell proliferation was observed with up to 25 µM of GNF7686. Our approach, which combines T. cruzi chemical genetics with biochemical target validation, can be broadly applied to the discovery of additional novel drug targets and drug leads for Chagas disease.

  12. ELISA versus PCR for diagnosis of chronic Chagas disease: systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Hasslocher-Moreno Alejandro M

    2010-11-01

    Full Text Available Abstract Background Most current guidelines recommend two serological tests to diagnose chronic Chagas disease. When serological tests are persistently inconclusive, some guidelines recommend molecular tests. The aim of this investigation was to review chronic Chagas disease diagnosis literature and to summarize results of ELISA and PCR performance. Methods A systematic review was conducted searching remote databases (MEDLINE, LILACS, EMBASE, SCOPUS and ISIWeb and full texts bibliography for relevant abstracts. In addition, manufacturers of commercial tests were contacted. Original investigations were eligible if they estimated sensitivity and specificity, or reliability -or if their calculation was possible - of ELISA or PCR tests, for chronic Chagas disease. Results Heterogeneity was high within each test (ELISA and PCR and threshold effect was detected only in a particular subgroup. Reference standard blinding partially explained heterogeneity in ELISA studies, and pooled sensitivity and specificity were 97.7% [96.7%-98.5%] and 96.3% [94.6%-97.6%] respectively. Commercial ELISA with recombinant antigens studied in phase three investigations partially explained heterogeneity, and pooled sensitivity and specificity were 99.3% [97.9%-99.9%] and 97.5% [88.5%-99.5%] respectively. ELISA's reliability was seldom studied but was considered acceptable. PCR heterogeneity was not explained, but a threshold effect was detected in three groups created by using guanidine and boiling the sample before DNA extraction. PCR sensitivity is likely to be between 50% and 90%, while its specificity is close to 100%. PCR reliability was never studied. Conclusions Both conventional and recombinant based ELISA give useful information, however there are commercial tests without technical reports and therefore were not included in this review. Physicians need to have access to technical reports to understand if these serological tests are similar to those included in

  13. Inositol metabolism in Trypanosoma cruzi: potential target for chemotherapy against Chagas' disease

    Directory of Open Access Journals (Sweden)

    MECIA M. OLIVEIRA

    2000-09-01

    Full Text Available Chagas' disease is a debilitating and often fatal disease caused by the protozoan parasite Trypanosoma cruzi. The great majority of surface molecules in trypanosomes are either inositol-containing phospholipids or glycoproteins that are anchored into the plasma membrane by glycosylphosphatidylinositol anchors. The polyalcohol myo-inositol is the precursor for the biosynthesis of these molecules. In this brief review, recent findings on some aspects of the molecular and cellular fate of inositol in T. cruzi life cycle are discussed and identified some points that could be targets for the development of parasite-specific therapeutic agents.

  14. Training Systems Modelers through the Development of a Multi-scale Chagas Disease Risk Model

    Science.gov (United States)

    Hanley, J.; Stevens-Goodnight, S.; Kulkarni, S.; Bustamante, D.; Fytilis, N.; Goff, P.; Monroy, C.; Morrissey, L. A.; Orantes, L.; Stevens, L.; Dorn, P.; Lucero, D.; Rios, J.; Rizzo, D. M.

    2012-12-01

    The goal of our NSF-sponsored Division of Behavioral and Cognitive Sciences grant is to create a multidisciplinary approach to develop spatially explicit models of vector-borne disease risk using Chagas disease as our model. Chagas disease is a parasitic disease endemic to Latin America that afflicts an estimated 10 million people. The causative agent (Trypanosoma cruzi) is most commonly transmitted to humans by blood feeding triatomine insect vectors. Our objectives are: (1) advance knowledge on the multiple interacting factors affecting the transmission of Chagas disease, and (2) provide next generation genomic and spatial analysis tools applicable to the study of other vector-borne diseases worldwide. This funding is a collaborative effort between the RSENR (UVM), the School of Engineering (UVM), the Department of Biology (UVM), the Department of Biological Sciences (Loyola (New Orleans)) and the Laboratory of Applied Entomology and Parasitology (Universidad de San Carlos). Throughout this five-year study, multi-educational groups (i.e., high school, undergraduate, graduate, and postdoctoral) will be trained in systems modeling. This systems approach challenges students to incorporate environmental, social, and economic as well as technical aspects and enables modelers to simulate and visualize topics that would either be too expensive, complex or difficult to study directly (Yasar and Landau 2003). We launch this research by developing a set of multi-scale, epidemiological models of Chagas disease risk using STELLA® software v.9.1.3 (isee systems, inc., Lebanon, NH). We use this particular system dynamics software as a starting point because of its simple graphical user interface (e.g., behavior-over-time graphs, stock/flow diagrams, and causal loops). To date, high school and undergraduate students have created a set of multi-scale (i.e., homestead, village, and regional) disease models. Modeling the system at multiple spatial scales forces recognition that

  15. A inserção institucional do controle da doença de Chagas

    Directory of Open Access Journals (Sweden)

    Antônio Carlos Silveira

    2011-01-01

    Full Text Available Em 1943, a partir da criação do "Centro de Estudos e Profilaxia da Moléstia de Chagas" da Fundação Oswaldo Cruz de Bambuí em Minas Gerais, são concebidas as bases tecnológicas e metodológicas para o controle extensivo da enfermidade. Para isso foi decisivo o advento de um novo inseticida (o gammexane, P 530 e a demonstração de sua eficácia no controle dos vetores da doença de Chagas. Como resultado prático desses acontecimentos em "maio de 1950 foi oficialmente inaugurada, em Uberaba, a primeira campanha de profilaxia da doença de Chagas, no Brasil". Mesmo que se dispusesse desde então de meios para fazer o controle da transmissão vetorial da endemia chagásica, não se dispunha dos recursos financeiros exigidos para fazê-lo de forma abrangente e regular. O baixo nível de prioridade conferida a essa atividade se expressava em sua inserção institucional. Em 1941, foram criados os Serviços Nacionais, de malária, peste, varíola, entre outros, enquanto a doença de Chagas fazia parte da Divisão de Organização Sanitária (DOS, que reunia enfermidades consideradas de menor importância. Em 1956 o Departamento Nacional de Endemias Rurais (DNERu incorporou todas as chamadas grandes endemias em uma única instituição, mas na prática isso não significou a implementação das ações de controle da doença de Chagas. Com a reestruturação do Ministério da Saúde em 1970, a Superintendência de Campanhas de Saúde Pública (SUCAM abarcou todas as endemias rurais, e a doença de Chagas passou a ter o status de Divisão Nacional, na mesma posição hierárquica daquelas outras doenças transmitidas por vetores antes consideradas prioritárias. Essa condição determinou a possibilidade de uma repartição de recursos mais equilibrada, o que efetivamente ocorreu, com a realocação de pessoal e insumos do programa de malária para o controle vetorial da doença de Chagas. Em 1991, a Fundação Nacional de Saúde sucedeu a SUCAM

  16. Training the Next Generation of Scientists: System Dynamics Modeling of Chagas Disease (American Trypanosomiasis) transmission.

    Science.gov (United States)

    Goff, P.; Hulse, A.; Harder, H. R.; Pierce, L. A.; Rizzo, D.; Hanley, J.; Orantes, L.; Stevens, L.; Justi, S.; Monroy, C.

    2015-12-01

    A computational simulation has been designed as an investigative case study by high school students to introduce system dynamics modeling into high school curriculum. This case study approach leads users through the forensics necessary to diagnose an unknown disease in a Central American village. This disease, Chagas, is endemic to 21 Latin American countries. The CDC estimates that of the 110 million people living in areas with the disease, 8 million are infected, with as many as 300,000 US cases. Chagas is caused by the protozoan parasite, Trypanosoma cruzi, and is spread via blood feeding insect (vectors), that feed on vertebrates and live in crevasses in the walls and roofs of adobe homes. One-third of the infected people will develop chronic Chagas who are asymptomatic for years before their heart or GI tract become enlarged resulting in death. The case study has three parts. Students play the role of WHO field investigators and work collaboratively to: 1) use genetics to identify the host(s) and vector of the disease 2) use a STELLA™ SIR (Susceptible, Infected, Recovered) system dynamics model to study Chagas at the village scale and 3) develop management strategies. The simulations identify mitigation strategies known as Ecohealth Interventions (e.g., home improvements using local materials) to help stakeholders test and compare multiple optima. High school students collaborated with researchers from the University of Vermont, Loyola University and Universidad de San Carlos, Guatemala, working in labs, interviewing researchers, and incorporating mulitple field data as part of a NSF-funded multiyear grant. The model displays stable equilibria of hosts, vectors, and disease-states. Sensitivity analyses show measures of household condition and presence of vertebrates were significant leverage points, supporting other findings by the University research team. The village-scale model explores multiple solutions to disease mitigation for the purpose of producing

  17. Carvedilol Enhances the Antioxidant Effect of Vitamins E and C in Chronic Chagas Heart Disease

    Energy Technology Data Exchange (ETDEWEB)

    Budni, Patrícia, E-mail: budnip@gmail.com [Universidade Federal de Santa Catarina, Florianópolis, SC (Brazil); Pedrosa, Roberto Coury [Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, RJ (Brazil); Dalmarco, Eduardo Monguilhott; Dalmarco, Juliana Bastos; Frode, Tânia Sílvia; Wilhelm, Danilo Filho [Universidade Federal de Santa Catarina, Florianópolis, SC (Brazil)

    2013-10-15

    Chagas disease is still an important endemic disease in Brazil, and the cardiac involvement is its more severe manifestation. To verify whether the concomitant use of carvedilol will enhance the antioxidant effect of vitamins E and C in reducing the systemic oxidative stress in chronic Chagas heart disease. A total of 42 patients with Chagas heart disease were studied. They were divided into four groups according to the modified Los Andes classification: 10 patients in group IA (normal electrocardiogram and echocardiogram; no cardiac involvement); 20 patients in group IB (normal electrocardiogram and abnormal echocardiogram; mild cardiac involvement); eight patients in group II (abnormal electrocardiogram and echocardiogram; no heart failure; moderate cardiac involvement); and four patients in group III (abnormal electrocardiogram and echocardiogram with heart failure; severe cardiac involvement). Blood levels of markers of oxidative stress were determined before and after a six-month period of treatment with carvedilol, and six months after combined therapy of carvedilol with vitamins E and C. The markers analyzed were as follows: activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase and reductase, myeloperoxidade and adenosine deaminase; and the levels of reduced glutathione, thiobarbituric-acid reactive substances, protein carbonyls, vitamin E, and nitric oxide. After treatment with carvedilol, all groups showed significant decrease in protein carbonyls and reduced glutathione levels, whereas nitric oxide levels and adenosine activity increased significantly only in the less severely affected group (IA). In addition, the activity of most of the antioxidant enzymes was decreased in the less severely affected groups (IA and IB). By combining the vitamins with carvedilol, a reduction in protein damage, in glutathione levels, and in the activity of most of the antioxidant enzymes were observed. The decrease in oxidative

  18. ESTUDIO SEROLOGICO POR INMUNOFLUORESCENCIA DE LA ENFERMEDAD DE CHAGAS EN COSTA RICA

    OpenAIRE

    LILIANA REYES; Bonilla, A.; T. MOYA; MISAEL CHINCHILLA

    1998-01-01

    RESUMEN Se estudiaron 1.043 sueros de pacientes provenientes de todo el territorio nacional por anticuerpos anti-Trypanosoma cruzi utilizando la técnica de inmunofluorescencia. Se demostró un porcentaje de positividad general de 2,14%. La mayor positividad se encontró en la provincia de San José (2,4%) y la menor en Heredia (0,8%).SEROLOGICAL STUDY OF CHAGAS DISEASE IN COSTA RICA BY IMMUNOFLUORESCENCE One thousand and fourty three patients were studied for anti-Trypanosoma cruzi antibodies by...

  19. Health-related quality of life in patients with Chagas disease

    OpenAIRE

    Bruna Guimarães Oliveira; Mery Natali Silva Abreu; Claudia Drummond Guimarães Abreu; Manoel Otavio da Costa Rocha; Antonio Luiz Ribeiro

    2011-01-01

    INTRODUCTION: Chagas disease (ChD) is a chronic illness related to significant morbidity and mortality that can affect the quality of life (QoL) of infected patients. However, there are few studies regarding QoL in ChD. The objectives of this study are to construct a health-related QoL (HRQoL) profile of ChD patients and compare this with a non-ChD (NChD) group to identify factors associated with the worst HRQoL scores in ChD patients. METHODS: HRQoL was investigated in 125 patients with ChD ...

  20. Carvedilol Enhances the Antioxidant Effect of Vitamins E and C in Chronic Chagas Heart Disease

    International Nuclear Information System (INIS)

    Chagas disease is still an important endemic disease in Brazil, and the cardiac involvement is its more severe manifestation. To verify whether the concomitant use of carvedilol will enhance the antioxidant effect of vitamins E and C in reducing the systemic oxidative stress in chronic Chagas heart disease. A total of 42 patients with Chagas heart disease were studied. They were divided into four groups according to the modified Los Andes classification: 10 patients in group IA (normal electrocardiogram and echocardiogram; no cardiac involvement); 20 patients in group IB (normal electrocardiogram and abnormal echocardiogram; mild cardiac involvement); eight patients in group II (abnormal electrocardiogram and echocardiogram; no heart failure; moderate cardiac involvement); and four patients in group III (abnormal electrocardiogram and echocardiogram with heart failure; severe cardiac involvement). Blood levels of markers of oxidative stress were determined before and after a six-month period of treatment with carvedilol, and six months after combined therapy of carvedilol with vitamins E and C. The markers analyzed were as follows: activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase and reductase, myeloperoxidade and adenosine deaminase; and the levels of reduced glutathione, thiobarbituric-acid reactive substances, protein carbonyls, vitamin E, and nitric oxide. After treatment with carvedilol, all groups showed significant decrease in protein carbonyls and reduced glutathione levels, whereas nitric oxide levels and adenosine activity increased significantly only in the less severely affected group (IA). In addition, the activity of most of the antioxidant enzymes was decreased in the less severely affected groups (IA and IB). By combining the vitamins with carvedilol, a reduction in protein damage, in glutathione levels, and in the activity of most of the antioxidant enzymes were observed. The decrease in oxidative

  1. Serum-Mediated Activation of Macrophages Reflects TcVac2 Vaccine Efficacy against Chagas Disease

    OpenAIRE

    Gupta, Shivali; Silva, Trevor S.; Osizugbo, Jessica E.; Tucker, Laura; Spratt, Heidi M.; Garg, Nisha J.

    2014-01-01

    Chagas disease is endemic in Latin America and an emerging infectious disease in the United States. No effective treatments are available. The TcG1, TcG2, and TcG4 antigens are highly conserved in clinically relevant Trypanosoma cruzi isolates and are recognized by B and T cells in infected hosts. Delivery of these antigens as a DNA prime/protein boost vaccine (TcVac2) elicited lytic antibodies and type 1 CD8+ T cells that expanded upon challenge infection and provided >90% control of parasit...

  2. Cardiac Repolarization Abnormalities and Potential Evidence for Loss of Cardiac Sodium Currents on ECGs of Patients with Chagas' Heart Disease

    Science.gov (United States)

    Schlegel, T. T.; Medina, R.; Jugo, D.; Nunez, T. J.; Borrego, A.; Arellano, E.; Arenare, B.; DePalma, J. L.; Greco, E. C.; Starc, V.

    2007-01-01

    Some individuals with Chagas disease develop right precordial lead ST segment elevation in response to an ajmaline challenge test, and the prevalence of right bundle branch block (RBBB) is also high in Chagas disease. Because these same electrocardiographic abnormalities occur in the Brugada syndrome, which involves genetically defective cardiac sodium channels, acquired damage to cardiac sodium channels may also occur in Chagas disease. We studied several conventional and advanced resting 12-lead/derived Frank-lead ECG parameters in 34 patients with Chagas -related heart disease (mean age 39 14 years) and in 34 age-/gender-matched healthy controls. All ECG recordings were of 5-10 min duration, obtained in the supine position using high fidelity hardware/software (CardioSoft, Houston, TX). Even after excluding those Chagas patients who had resting BBBs, tachycardia and/or pathologic arrhythmia (n=8), significant differences remained in multiple conventional and advanced ECG parameters between the Chagas and control groups (n=26/group), especially in their respective QT interval variability indices, maximal spatial QRS-T angles and low frequency HRV powers (p=0.0006, p=0.0015 and p=0.0314 respectively). In relation to the issue of potential damage to cardiac sodium channels, the Chagas patients had: 1) greater than or equal to twice the incidence of resting ST segment elevation in leads V1-V3 (n=10/26 vs. n=5/26) and of both leftward (n=5/26 versus n=0/26) and rightward (n=7/26 versus n=3/26) QRS axis deviation than controls; 2) significantly increased filtered (40-250 Hz) QRS interval durations (92.1 8.5 versus 85.3 plus or minus 9.0 ms, p=0.022) versus controls; and 3) significantly decreased QT and especially JT interval durations versus controls (QT interval: 387.5 plus or minus 26.4 versus 408.9 plus or minus 34.6 ms, p=0.013; JT interval: 290.5 plus or minus 26.3 versus 314.8 plus or minus 31.3 ms; p=0.0029). Heart rates and Bazett-corrected QTc/JTc intervals

  3. Thermo-optic Imbert-Fedorov effect in a prism-waveguide coupling system with silicon-on-insulator

    Science.gov (United States)

    Tang, Tingting; Li, Chaoyang; Luo, Li; Zhang, Yanfen; Yuan, Quan

    2016-07-01

    In this paper, a prism-waveguide coupling system based on silicon-on-insulator (SOI) is revisited. We find that thermo-optic Imbert-Fedorov (TOIF) effect displays in this four-layer optical system which has not been proposed before. Furthermore, we discuss the TOIF shifts in prism/SiO2/Si/SiO2 and prism/Au/Si/SiO2 waveguides with different parameters and study the observed phenomena from physical point of view. It is shown that the maximum IF shift can achieve 140 μm in a prism/Au/Si/SiO2 waveguide which is large enough to be directly measured by the calculation results. Accordingly, TOIF shift provides a temperature control method for the enhancement and modulation of IF shift.

  4. Tomographic particle image velocimetry over a triangular prism in unidirectional flows

    Science.gov (United States)

    Sou, In Mei; Calantoni, Joseph

    2011-11-01

    Using tomographic particle image velocimetry (Tomo-PIV), the full three-dimensional-three-component (3D-3C) flow structure and turbulence characteristics over a triangular prism in a recirculating water tunnel were investigated. Here we present preliminary results from a new Tomo-PIV system for subcritical Froude number flows. Large-scale vortex shedding from the tip of the triangular prism is observed. Results of coherent structure organization analyzed by 3D vorticity calculation will be presented. Using the full 3D-3C instantaneous velocity field, turbulent kinetic energy is directly evaluated without any of the assumptions often needed for 2D PIV measurements. Details of the experimental setup including a unique device designed to perform our Tomo-PIV volume calibration will be discussed. We perform an in-depth turbulent kinetic energy budget and explore the feasibility of extending the measurement technique to other complex flows.

  5. Experimental Evaluation of Lightweight AAC Masonry Wall Prisms with Ferrocement Layers in Compression and Flexure

    KAUST Repository

    Abdel Mooty, Mohamed

    2012-05-01

    An experimental program is designed to evaluate the performance of lightweight autoclaved aerated concrete masonry wall strengthened using ferrocement layers, in a sandwich structure, under in-plane compression and out-of-plane bending. The 25 mm thick ferrocement mortar is reinforced with steel welded wire mesh of 1 mm diameters at 15 mm spacing. Different types of shear connectors are used to evaluate their effect on failure loads. The effect of different design parameters on the wall strength are considered including wall thickness, mortar strength, and type and distribution of shear connectors. A total of 20 prisms are tested in compression and 5 prisms are tested under bending. The proposed ferrocement strengthening technique is easy to apply on existing wall system and results in significant strength and stiffness enhancement of the tested wall specimens. © (2012) Trans Tech Publications.

  6. Efficient broadband second-harmonic generation by dispersive achromatic nonlinear conversion using only prisms

    International Nuclear Information System (INIS)

    Using a lossless dispersive apparatus consisting of six prisms, optimized to match a second-harmonic crystal phase-matching angle versus wavelength to second order, we efficiently doubled tunable fundamental light near 660nm over a range of 80nm, using a 4-mm-long type I β-barium borate crystal without tuning the crystal angle. Another set of six prisms after the crystal realigned the propagation directions of the various second-harmonic frequencies to be collinear to within 1/4 spot diameter in position and 200 μrad in angle. The measured conversion efficiency of a 40-mJ, 5-ns fundamental pulse was 10%. copyright 1998 Optical Society of America

  7. A beam separator of a close packed prism array for low energy electron microscopy

    International Nuclear Information System (INIS)

    The electron optical properties of a beam separator made of a ''Chicane'' type close packed prism array proposed by Kolarik et al. [Optik 87 (1991) 1] have been analyzed. The total deflection angle of the illumination beam is 90 and that of the image forming beam is 0 . The second order aberrations are estimated using the eikonal method developed by Rose [Optik 51 (1978) 15] under the SCOFF approximation. It has a limitation in the analysis of the close packed prism array, because of the overlapped fringing field distributions. The magnetic field distributions of the separator are numerically calculated using the three dimensional finite difference method followed by direct ray tracing. The angles of the edge were readjusted by trial and error to get the stigmatic focus of the beam. (orig.)

  8. The Refractive Index Measurement Of Silicon Dioxide Thin Film by the Coupling Prism Method

    International Nuclear Information System (INIS)

    Refractive index of silicon dioxide thin film that doped with phosphor (SiO2:P) above the pure silicon dioxide substrate has been measured by light coupling prism method. The method principle is focusing the light on coupling prism base so that the light propagates into the waveguide layer while the reflected one forms a mode in the observation plane. The SiO2 thin film as waveguide layer has a refractive index that give the thick and refractive index relation. The He-Ne laser as light source has the wavelength λ 0,6328 μm. The refractive index measurement of the thin film with the substrate refractive index nsb = 1,47 and the thin film thick d = 2μm gives ng = 1,5534 ± 0,01136. This method can distinguish the refractive index of thin film about 6% to the refractive index of substrate

  9. Prism dispersion effects in near-guided-wave surface plasmon resonance sensors

    International Nuclear Information System (INIS)

    Refractive index dispersion causes the light line to curve. As a result it is shown that when the prism is dispersive, an additional dip in the spectral response of Surface Plasmon Resonance (SPR) sensors is observed in the Kretschmann-Raether (KR) configuration. Since the new dip evolves in the infrared (IR) region, it exhibits a high sensitivity to the analyte refractive index (RI) changes and the mode penetrates deeper into the analyte. Adding a thin dielectric layer with high refractive index on top of the metallic layer enables to control the dip location and strength. The two dips shift in opposite directions as the analyte RI changes and therefore when the spectral difference is considered as the measurand, higher RI sensitivity is obtained. The dispersion relation of two thin films bounded by two semi-infinite media is derived when the prism dispersion is considered. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Dispersive radio frequency electrometry using Rydberg atoms in a prism-shaped atomic vapor cell

    Science.gov (United States)

    Fan, H. Q.; Kumar, S.; Kübler, H.; Shaffer, J. P.

    2016-05-01

    We introduce a method to measure radio frequency (RF) electric fields (E-fields) using atoms contained in a prism-shaped vapor cell. The method utilizes the concept of electromagnetically induced transparency with Rydberg atoms. The RF E-field induces changes in the index of refraction of the vapor resulting in deflection of the probe laser beam as it passes through the prism-shaped vapor cell. We measured a minimum RF E-field of 8.25 μ {{Vcm}}-1 with a sensitivity of ∼ 46.5 μ {{Vcm}}-1 {{Hz}}-1/2. The experimental results agree with a numerical model that includes dephasing effects. We discuss possible improvements to obtain higher sensitivity for RF E-field measurements.

  11. Moving forward with prisms: Sensory-motor adaptation improves gait initiation in Parkinson’s disease.

    Directory of Open Access Journals (Sweden)

    Janet Helen Bultitude

    2012-09-01

    Full Text Available It is postulated that the decreased walking speed; small, shuffling steps; and ‘freezing’ shown by patients with Parkinson’s disease could stem from an inability to tilt the body forward enough to provide sufficient forward propulsion. In two repeated-measures studies we examined whether adaptation to upward-shifting prisms, resulting in a downward after-effect, could improve gait initiation in healthy participants and patients with Parkinson’s disease. Faster forward stepping followed a brief (5 min exposure period for patients, and a longer (20 min exposure period for age-matched controls. Backward stepping was unchanged, and adaptation to downward-shifting prisms with control participants showed no effect on forward or backward stepping. These results suggest that adaptation of arm proprioception in the vertical plane may generalise to anterior-posterior postural control, presenting new possibilities for the treatment of gait disturbance in basal ganglia disorders.

  12. HEATING OF BLANK IN FORM OF PRISM IN ACCORDANCE WITH TECHNOLOGICAL LIMITATIONS

    Directory of Open Access Journals (Sweden)

    V. B. Kovalevsky

    2009-01-01

    Full Text Available The paper considers a problem on optimum heating control of a blank in the form of prism under complicated conditions of heat-transfer in accordance with criteria of gas consumption minimization, decarburized layer and scaling. Numerical algorithm of the problem solution and examples are given in the paper. A new technology of the flame furnace operation has been developed in the paper. 

  13. ANALISIS PENGUKURAN KINERJA PERUSAHAAN DENGAN METODE PERFORMANCE PRISM DAN SCORING OBJECTIVE MATRIX (OMAX) PADA PT. BPAS

    OpenAIRE

    Adianto .; M. Agung Saryatmo; Ardi S. Gunawan

    2014-01-01

    Kinerja merupakan suatu tampilan keadaan secara utuh atas perusahaan selama periode waktu tertentu. PT. BPAS adalah sebuah perusahaan yang bergerak dalam bidang industri papan semen. Selama ini sistem pengukuran kinerja di PT. BPAS belum merepresentasikan kinerja organisasi secara komprehensif dan integratif. Oleh sebab itu pengukuran kinerja perlu dilakukan pada PT. BPAS dengan menggunakan metode Performance Prism dan Scoring OMAX agar dapat meningkatkan kinerja perusahaan secara maksimal. P...

  14. PRISM [Power Reactor Inherently Safe Module] design concept enhances waste management

    International Nuclear Information System (INIS)

    PRISM, a modular advanced liquid metal reactor (ALMR), has been designed conceptually by GE under the US Department of Energy sponsorship. The concept design and analyses have been primarily focused on passive safety and improved construction and operating costs. Significantly, the unique design of multiple modules and features of PRISM enhance waste management over conventional reactor systems. This paper provides an overview of PRISM of these enhancements. Inherent to the ALMR's, the sodium coolant precludes crud buildup on reactor surfaces and in components and waste for disposal. Preliminary evaluations indicate this fundamental feature results in factors of 2-4 less waste volume and 2-3 orders of magnitude less curies per megawatt-electric for ultimate disposal. For example, the tap designed for sodium cleanup is expected to be exchanged only once every thirty years. Also, inherent to ALMR's, burning waste actinides and selected fission products to preclude their accumulation and burial is very attractive. The hard neutron spectrum of ALMR burns the actinides efficiently and is not poisoned by the actinides and fission products. The modular design of PRISM components (and the fuel cycle equipment) permit replacement without expensive and potentially hazardous volume reduction. For example, the functional components of the reference electromagnetic pump and IHK can be removed intact for waste disposal. Although development of the reference metal fuel is not completed, it is estimated that (low-level) waste from recycle of the fuel will result in significantly less volume than would be generated by aqueous recycle of oxide fuel. 6 refs., 10 figs

  15. Improvement of Mental Imagery after Prism Exposure in Neglect: A Case Study

    OpenAIRE

    Gilles Rode; Yves Rossetti; Ling Li; Dominique Boisson

    1999-01-01

    Previous work has shown that various symptoms of unilateral neglect, including the pathological shift of the subjective midline to the right, may be improved by a short adaptation period to a prismatic shift of the visual field to the right. We report here the improvement of imagined neglect after prism exposure in a patient with a left unilateral neglect. Despite a strong neglect observed for mental images as well as for conventional tests, the mental evocation of left-sided information from...

  16. Prism adaptation reverses the local processing bias in patients with right temporo-parietal junction lesions

    OpenAIRE

    Bultitude, Janet H.; Rafal, Robert D.; List, Alexandra

    2009-01-01

    Lesions to the right temporo-parietal cortex commonly result in hemispatial neglect. Lesions to the same area are also associated with hyperattention to local details of a scene and difficulty perceiving the global structure. This local processing bias is an important factor contributing to neglect and may contribute to the higher prevalence of the disorder following right compared with left hemisphere strokes. In recent years, visuomotor adaptation to rightward-shifting prisms has been intro...

  17. A scalable expressive ensemble learning using Random Prism: a MapReduce approach

    OpenAIRE

    Stahl, Frederic; May, David; Mills, Hugo; Bramer, Max; Gaber, Mohamed Medhat

    2015-01-01

    The induction of classification rules from previously unseen examples is one of the most important data mining tasks in science as well as commercial applications. In order to reduce the influence of noise in the data, ensemble learners are often applied. However, most ensemble learners are based on decision tree classifiers which are affected by noise. The Random Prism classifier has recently been proposed as an alternative to the popular Random Forests classifier, which is based on decision...

  18. High-resolution NO₂ remote sensing from the Airborne Prism EXperiment (APEX) imaging spectrometer

    OpenAIRE

    Popp, C; Brunner, D.; Damm, A.; Van Roozendael, M.; Fayt, C.; Buchmann, B

    2012-01-01

    We present and evaluate the retrieval of high spatial resolution maps of NO2 vertical column densities (VCD) from the Airborne Prism EXperiment (APEX) imaging spectrometer. APEX is a novel instrument providing airborne measurements of unique spectral and spatial resolution and coverage as well as high signal stability. In this study, we use spectrometer data acquired over Zurich, Switzerland, in the morning and late afternoon during a flight campaign on a cloud-free summer d...

  19. A study on transmitted intensity of disturbance for air-spaced Glan-type polarizing prisms

    OpenAIRE

    Fan, Ji-Yang; Li, Hong-Xia; Wu, Fu-Quan

    2002-01-01

    We study theoretically and experimentally the transmission intensity of polarized light through the air-spaced Glan-type polarizing prsims. It is found that the variation of the transmitted intensity with the rotation angle deviates from Malus Law, exhibiting a cyclic fluctuation with the rotation angle. The occurrence of the disturbance is explained by the use of an argument based on the interference effect produced from the air-gap in the prisms. The theoretcal results are well agreed with ...

  20. Existence of a Diffusion Length in a Finite Prism of Pure Moderator

    International Nuclear Information System (INIS)

    An exact integral transport equation is derived for the neutron flux in a finite prism of pure moderator. Assuming that the prism is infinite in the z-direction, a trial solution expi(-vz) is inserted, and an eigenvalue problem for v, the spatial relaxation constant, results. The eigenvalue v is studied as a function of the absorption and dimensions of the prism. It is shown that the discrete eigenvalues are bounded by Σmin, and that a minimum dimension exists below which a diffusion length can no longer be found. This result is much more restrictive than the maximum absorption theorem of Comgold, and the minimum dimension of the prism is shown to correspond to transverse bucklings of 10-3 cm2 for beryllium, and 1.5 x 10-3cm2 for graphite, at 300°K. For poisoned and low-temperature moderators these values will be even smaller. The angular distribution of the neutrons in the moderator has been calculated perpendicular and parallel to the axis, and it is found that a marked anisotropy of the spectrum exists, particularly in the neighbourhood of the Bragg cut-off. On the basis of degenerate kernel approximation to the scattering process, it is shown that when the system is such that no diffusion length exists, then the asymptotic transverse flux shape is no longer of the cosine type, but becomes progressively flatter as the distance from the source increases. This is due to an increase in the proportion of cold neutrons which have longer mean free paths than the average. The well-known cold neutron filtering effect can be explained in terms of this phenomenon. The results obtained from the present analysis are in quantitative agreement with recent experiments performed by De Juren and Swanson. (author)

  1. [Effectivity of different methods for disinfection of applanation tonometer prisms (author's transl)].

    Science.gov (United States)

    Wizemann, A

    1980-01-01

    In 13,440 bacteriological investigations the effectivity of different methods for desinfection of Goldmann tonometer prisms (merfen, pantasept, sekusept steril, UV sterilizer Sklar) is tested. Sekusept steril and UV sterilizer show the quickest and most sufficient results. They cause no damage to corneal epithelium or to plastic objects. We can recommend them for desinfection of applanation tonometer prims, Goldmann's gonioscopy and fundus contact lenses as routine methods.

  2. Optimization of the laser beam propagation conditions in the prism stretcher of THL-100 multiterawatt laser system

    OpenAIRE

    Ivanov, Mikhail Vladimirovich; Alekseev, Sergey Vladimirovich; Ivanov, Nikolay Georgievich; Losev, Valery Fedorovich

    2015-01-01

    The influence of the optical inhomogeneities effect of the prism stretcher elements on the spatial, angular and spectral parameters of the transmitted radiation and the degree of change in the phase aberrations of the laser beam during its propagation in the stretcher are studied. It is shown that the prism material does not allow transmitting of a required diameter of 75 mm without linear distortions of the beam. The maximum intensity and beam diameter allowing to amplify the picosecond puls...

  3. PRISM: a web server and repository for prediction of protein–protein interactions and modeling their 3D complexes

    OpenAIRE

    Baspinar, Alper; Cukuroglu, Engin; Nussinov, Ruth; Keskin, Ozlem; Gursoy, Attila

    2014-01-01

    The PRISM web server enables fast and accurate prediction of protein–protein interactions (PPIs). The prediction algorithm is knowledge-based. It combines structural similarity and accounts for evolutionary conservation in the template interfaces. The predicted models are stored in its repository. Given two protein structures, PRISM will provide a structural model of their complex if a matching template interface is available. Users can download the complex structure, retrieve the interface r...

  4. Impact of Chagas Disease in Bolivian Immigrants Living in Europe and the Risk of Stigmatization

    Directory of Open Access Journals (Sweden)

    Rafael M. Ortí-Lucas

    2014-01-01

    Full Text Available Background. The prevalence of Chagas disease in endemic countries varies with the kind of vector involved and the socioeconomic conditions of the population of origin. Due to recent immigration it is an emerging public health problem in Europe, especially in those countries which receive immigrant populations with a high prevalence of carriers. The study reviews the impact of the disease on Bolivian immigrants living in Europe, the preventive measures and regulations applied in European countries, and their repercussion on possible stigmatization of certain population groups. Methods. The Bolivian immigrant population resident in 2012 was estimated and the affected population in different European countries was calculated with data on carrier prevalence that were recently published. The preventive measures and regulations available in Europe were also reviewed. MEDLINE-PubMed, GoPubMed, and Embase were consulted for the literature review. Results. The Bolivian immigrant population has the highest prevalence of Chagas carriers (6.7%–25% compared to the overall Latin American population (1.3%–2.4%. Only in Spain, France, Belgium, UK, Portugal, Italy, Switzerland, The Netherlands, and Germany, preventive measures are applied to this population. The established regulations are insufficient and completely different criteria are applied in the different countries and this could reflect a certain degree of stigmatization.

  5. Bibliometric assessment of the contributions of literature on Chagas disease in Latin America and the Caribbean.

    Science.gov (United States)

    Delgado-Osorio, Nathalia; Vera-Polania, Felipe; Lopez-Isaza, Andres F; Martinez-Pulgarin, Dayron F; Murillo-Abadia, Jonathan; Munoz-Urbano, Marcela; Cardona-Ospina, Jaime A; Bello, Ricardo; Lagos-Grisales, Guillermo J; Villegas-Rojas, Soraya; Rodriguez-Morales, Alfonso J

    2014-01-01

    Chagas disease, considered a parasitic neglected disease, is endemic in Latin America. Although, its mortality rate has decreased over time, it still represents a public health problem in the region. A bibliometric evaluation of the Latin American contributions on this disease was done. This study used SCI (1980-2013), MEDLINE/GOPUBMED (1802-2013), Scopus (1959-2013), SCIELO (2004-2013), and LILACS (1980-2013). Different study types have been characterized by years, origin city/country, journals and most productive authors, by country, cites and H-index. 2988 articles were retrieved from SCI (30.85% of total). Brazil was found to be the highest producer (31.22%), followed by Argentina (18.14%) and México (9.57%); the region received 47241 citations, 28.60% for Brazil (H-index=52), 18.26% of Argentina (Hindex= 43), 11.40% Bolivia (H-index=37). 4484 were retrieved from Scopus (30.20% of the total), 38.58% of which were from Brazil, 12.40% from Argentina and 8.90% from Mexico. From Medline, 6647 records were retrieved (45.58% Brazil). From SciELO, 917 articles (47.66% Brazil). From LILACS, 2165 articles (60.05% Brazil). Brazil has the highest output in the region. Despite advances in controlling Chagas disease, scientific production is low, particularly for regional bibliographic databases, which calls for more research on this disease.

  6. Geographic Distribution of Chagas Disease Vectors in Brazil Based on Ecological Niche Modeling

    Directory of Open Access Journals (Sweden)

    Rodrigo Gurgel-Gonçalves

    2012-01-01

    Full Text Available Although Brazil was declared free from Chagas disease transmission by the domestic vector Triatoma infestans, human acute cases are still being registered based on transmission by native triatomine species. For a better understanding of transmission risk, the geographic distribution of Brazilian triatomines was analyzed. Sixteen out of 62 Brazilian species that both occur in >20 municipalities and present synanthropic tendencies were modeled based on their ecological niches. Panstrongylus geniculatus and P. megistus showed broad ecological ranges, but most of the species sort out by the biome in which they are distributed: Rhodnius pictipes and R. robustus in the Amazon; R. neglectus, Triatoma sordida, and T. costalimai in the Cerrado; R. nasutus, P. lutzi, T. brasiliensis, T. pseudomaculata, T. melanocephala, and T. petrocchiae in the Caatinga; T. rubrovaria in the southern pampas; T. tibiamaculata and T. vitticeps in the Atlantic Forest. Although most occurrences were recorded in open areas (Cerrado and Caatinga, our results show that all environmental conditions in the country are favorable to one or more of the species analyzed, such that almost nowhere is Chagas transmission risk negligible.

  7. The effect of Ageratum fastigiatum extract on Rhodnius nasutus, vector of Chagas disease

    Directory of Open Access Journals (Sweden)

    Bethânia A. Avelar-Freitas

    2013-04-01

    Full Text Available Control of Chagas disease is based on insecticide spraying in domiciles in order to exterminate triatomine populations. However, since the vectors differ in susceptibility to currently used insecticides, the screening of the toxic potential of Brazilian flora may identify new molecules lethal to triatomines. This study evaluated the toxicity of ethanolic extract of Ageratum fastigiatum (Gardner R.M. King & H. Rob., Asteraceae, on Rhodnius nasutus, a known vector of Chagas disease. Ethanolic extracts of the aerial parts of A. fastigiatum were prepared at 25 and 50 mg/mL concentrations, and 5 µL was applied to fifth-instar nymphs of R. nasutus (n=30. Controls included nymphs that were treated with 5 µL ethanol (n=30 or left untreated (n=30. The percentage of dead insects in each group was observed at 24, 48, 72, 96 and 120 h after application. The extracts of A. fastigiatum showed a mortality rate of about 37% and 77% after 120 h, at concentrations of 25 and 50 mg/mL, respectively. In control groups, the mortality rate remained under 7%. The extract of A. fastigiatum contains a coumarin, a molecule with recognized toxicity in insects, and which may be responsible for killing the triatomines.

  8. Entomological factors affecting the low endemicity of Chagas disease in Nazca, Southwestern Peru.

    Science.gov (United States)

    Paredes-Esquivel, Claudia; Lecaros, Emilio; Aguliar-Rosales, Mauro; Acosta, Hilda Solis; Castellanos, Pedro

    2010-05-01

    Chagas disease is prevalent in Peru. The province of Nazca, in the southwestern region of the country, shows a high intradomiciliary infestation rate of Triatoma infestans bugs. Although the vector is present, the number of Chagas disease cases appears to be much lower than those reported in the neighboring region of Arequipa. We examined 624 T. infestans from Nazca to determine the current Trypanosoma cruzi infection rates, and found that no bugs were infected with this parasite. These results contrast with those found in Arequipa, where 19-30% triatomines have been reported infected. To compare their vectorial capacity, we infected 30 T. infestans specimens, selected both from Nazca and Arequipa, by feeding bugs on T. cruzi-infected mice. The parasites developed all stages expected in the vector; furthermore, the infective stage, metacyclic trypomastigote, was found in both insect populations from the second week after infection. In addition, those insects that accepted to be fed with mice blood defecated immediately after finishing blood meal, indicating that they might be efficient vectors. We maintain that differences observed in infection rates between vectors from Nazca and Arequipa may be explained by differences in host availability. In Arequipa hosts are mainly small animals, whereas in Nazca the main blood source comes from birds, which are refractory to the infection.

  9. [Epidemiological status of Chagas disease in the endemic area from Region II of Antofagasta].

    Science.gov (United States)

    Cáceres, J; Burchard, L; Bahamonde, M I; Contreras, M C; García, A; Rojas, A; Schenone, H; Lorca, M

    1999-01-01

    During 1997 a seroepidemiological study on Chagas' disease was carried out in 18 localities of three provinces (Tocopilla, El Loa and Antofagasta) of Region II (20 degrees 56'-26 degrees South Lat.; 70 degrees 38'-67 degrees West Long.), in order to assess the impact of the control program against Triatoma infestans launched in 1988, based on insecticide spraying of dwellings. By means of ELISA and an indirect hemagglutination test for Chagas' disease blood samples from 1,034 children under 10 years of age were examined, arising a 0.5% (3 cases) positivity. Test resulted positive in 2 (0.9%) children from the locality of San Pedro de Atacama and 1 (0.4%) from Calama city, all in the age group 6-10 year-old. However, none of their dwellings were found infested with T. infestants. These results indicate that the control program has a good possibility to prevent new human infections. It is advisable to continue the seroepidemiological and entomological vigilance and remark the necessity of increasing the effort in the study of transmission through other routes, to adopt or reinforce the pertinent preventive measures.

  10. [Epidemiological status of Chagas disease in the endemic area from Region II of Antofagasta].

    Science.gov (United States)

    Cáceres, J; Burchard, L; Bahamonde, M I; Contreras, M C; García, A; Rojas, A; Schenone, H; Lorca, M

    1999-01-01

    During 1997 a seroepidemiological study on Chagas' disease was carried out in 18 localities of three provinces (Tocopilla, El Loa and Antofagasta) of Region II (20 degrees 56'-26 degrees South Lat.; 70 degrees 38'-67 degrees West Long.), in order to assess the impact of the control program against Triatoma infestans launched in 1988, based on insecticide spraying of dwellings. By means of ELISA and an indirect hemagglutination test for Chagas' disease blood samples from 1,034 children under 10 years of age were examined, arising a 0.5% (3 cases) positivity. Test resulted positive in 2 (0.9%) children from the locality of San Pedro de Atacama and 1 (0.4%) from Calama city, all in the age group 6-10 year-old. However, none of their dwellings were found infested with T. infestants. These results indicate that the control program has a good possibility to prevent new human infections. It is advisable to continue the seroepidemiological and entomological vigilance and remark the necessity of increasing the effort in the study of transmission through other routes, to adopt or reinforce the pertinent preventive measures. PMID:10488587

  11. Chagas' disease and Duffy antigen/receptor for chemokine (DARC: a mini-review

    Directory of Open Access Journals (Sweden)

    AP Oliveira

    2011-01-01

    Full Text Available Duffy gene (FY codifies the transmembrane glycoprotein Duffy (gp-Fy of 35 to 43 kDa which is moderately immunogenic. This glycoprotein is polymorphic, and constitutes the antigens of the Duffy histo-blood system which were designated receptors for chemokines and denominated DARC (Duffy antigen/receptor for chemokine. This receptor has an important role in the regulation of chemokine levels in the circulation, as it binds and adsorbs them on the surface of red cells as a reservoir. It plays a "sink" role, which can contribute to homeostasis by removing inflammatory chemokines from circulation as well as maintaining them in plasmatic levels. Chronic Chagas' cardiopathy (CCC is the most frequent form of the disease. It is an inflammatory disease, in which infiltrated inflammatory cells play an important role in the development and progress of the infection. High chemokine levels in the plasma have been associated with the disease severity in patients with heart failure. In this context, the profile of DARC expression could play an important function as a receptor for chemokines in Chagas' disease, in patients with CCC, as it can modulate damage from this inflammatory disease.

  12. Gas exchange during exercise in different evolutional stages of chronic Chagas' heart disease

    Directory of Open Access Journals (Sweden)

    Fátima Palha de Oliveira

    2000-12-01

    Full Text Available OBJECTIVE: To compare gas exchange at rest and during exercise in patients with chronic Chagas' heart disease grouped according to the Los Andes clinical/hemodynamic classification. METHODS: We studied 15 healthy volunteers and 52 patients grouped according to the Los Andes clinical/hemodynamic classification as follows: 17 patients in group IA (normal electrocardiogram/echocardiogram, 9 patients in group IB (normal electrocardiogram and abnormal echocardiogram, 14 patients in group II (abnormal electrocardiogram/echocardiogram, without congestive heart failure, and 12 patients in group III (abnormal electrocardiogram/echocardiogram with congestive heart failure. The following variables were analyzed: oxygen consumption (V O2, carbon dioxide production (V CO2, gas exchange rate (R, inspiratory current volume (V IC, expiratory current volume (V EC, respiratory frequency, minute volume (V E, heart rate (HR, maximum load, O2 pulse, and ventilatory anaerobic threshold (AT. RESULTS: When compared with the healthy group, patients in groups II and III showed significant changes in the following variables: V O2peak, V CO2peak, V ICpeak, V ECpeak, E, HR, and maximum load. Group IA showed significantly better results for these same variables as compared with group III. CONCLUSION: The functional capacity of patients in the initial phase of chronic Chagas' heart disease is higher than that of patients in an advanced phase and shows a decrease that follows the loss in cardiac-hemodynamic performance.

  13. Diagnostic electrocardiography in epidemiological studies of Chagas' disease: multicenter evaluation of a standardized method.

    Science.gov (United States)

    Lázzari, J O; Pereira, M; Antunes, C M; Guimarães, A; Moncayo, A; Chávez Domínguez, R; Hernández Pieretti, O; Macedo, V; Rassi, A; Maguire, J; Romero, A

    1998-11-01

    An electrocardiographic recording method with an associated reading guide, designed for epidemiological studies on Chagas' disease, was tested to assess its diagnostic reproducibility. Six cardiologists from five countries each read 100 electrocardiographic (ECG) tracings, including 30 from chronic chagasic patients, then reread them after an interval of 6 months. The readings were blind, with the tracings numbered randomly for the first reading and renumbered randomly for the second reading. The physicians, all experienced in interpreting ECGs from chagasic patients, followed printed instructions for reading the tracings. Reproducibility of the readings was evaluated using the kappa (kappa) index for concordance. The results showed a high degree of interobserver concordance with respect to the diagnosis of normal vs. abnormal tracings (kappa = 0.66; SE 0.02). While the interpretations of some categories of ECG abnormalities were highly reproducible, others, especially those having a low prevalence, showed lower levels of concordance. Intraobserver concordance was uniformly higher than interobserver concordance. The findings of this study justify the use by specialists of the recording of readings method proposed for epidemiological studies on Chagas' disease, but warrant caution in the interpretation of some categories of electrocardiographic alterations.

  14. Chagas disease in Mexico: an analysis of geographical distribution during the past 76 years - A review

    Directory of Open Access Journals (Sweden)

    Alejandro Cruz-Reyes

    2006-06-01

    Full Text Available Literature from 1928 through 2004 was compiled from different document sources published in Mexico or elsewhere. From these 907 publications, we found 19 different topics of Chagas disease study in Mexico. The publications were arranged by decade and also by state. This information was used to construct maps describing the distribution of Chagas disease according to different criteria: the disease, vectors, reservoirs, and strains. One of the major problems confronting study of this zoonotic disease is the great biodiversity of the vector species; there are 30 different species, with at least 10 playing a major role in human infection. The high variability of climates and biogeographic regions further complicate study and understanding of the dynamics of this disease in each region of the country. We used a desktop Genetic Algorithm for Rule-Set Prediction procedure to provide ecological models of organism niches, offering improved flexibility for choosing predictive environmental and ecological data. This approach may help to identify regions at risk of disease, plan vector-control programs, and explore parasitic reservoir association. With this collected information, we have constructed a data base: CHAGMEX, available online in html format.

  15. Genetic variants in the chemokines and chemokine receptors in Chagas disease.

    Science.gov (United States)

    Flórez, Oscar; Martín, Javier; González, Clara Isabel

    2012-08-01

    Clinical symptoms of Chagas' disease occur in 30% of the individuals infected with Trypanosoma cruzi and are characterised by heart inflammation and dysfunction. Chemokines and chemokine receptors control the migration of leukocytes during the inflammatory process and are involved in the modulation of Th1 or Th2 responses. To determine their influence, we investigated the possible role of CCL5/RANTES and CXCL8/IL8 chemokines, and CCR2 and CCR5 chemokines receptors cluster gene polymorphisms with the development of chagasic cardiomyopathy. Our study included 260 Chagas seropositive individuals (asymptomatic, n=130; cardiomyopathic, n=130) from an endemic area of Colombia. Genotyping was performed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and TaqMan SNP genotyping assay. We found statistically significant differences in the distribution of the CCR5 human haplogroup (HH)-A (p=0.027; OR=3.78, 95% CI=1.04-13.72). Moreover, we found that the CCR5-2733 G and CCR5-2554 T alleles are associated, respectively, with a reduced risk of susceptibility and severity to develop chagasic cardiomyopathy. No other associations were found to be significant for the other polymorphisms analysed in the CCR5, CCR2, CCL5/RANTES and CXCL8/IL8 genes. Our data suggest that the analysed chemokines and chemokine receptor genetic variants have a weak but important association with the development of chagasic cardiomyopathy in the population under study.

  16. Serological survey for Chagas' disease in school children in the Rio de Janeiro State, Brazil

    Directory of Open Access Journals (Sweden)

    Walter B. Petana

    1976-04-01

    Full Text Available A serological survey for Chagas' disease was carried out in school children in the Rio de Janeiro State, a zone considered as non-endemic for the infection. A total of 168 schools in 20 municipalities have been visited and 13,254 blood samples were obtained. The blood eluates were screened by the indirect fluorescence test (IFT, and all positive samples were checked and confirmed in sera by the complement fixation test (CFT. AH serologically positive children were subject to a clinical scrutiny, and the houses where the children lived have been searched for triatomine bugs. Only in two municipalities, Magé and Araruama, there was a significant number of children found positive. The total number of reactive samples by IFT and CFT from 13,004 blood samples screened was 143 (1.00 per cent. No serious clinicai symptoms suggestive of Chagas' disease have been found in any of the positive children, and no triatomine bugs were discovered in the dwellings where the children lived. The overall small percentage of children with positive serology postulates that the infection is not a serious health problem in the area investigated. It is recommended, however, to carry out a more detailed study in Magé and Araruama to find the reason for the relatively high percentage of serologically positive children encountered in these two municipalities.

  17. Conventional serological performance in diagnosis of Chagas' disease in southern Brazil

    Directory of Open Access Journals (Sweden)

    Anelise Bergmann Araújo

    2013-04-01

    Full Text Available Results of Chagas' disease diagnosis show disagreement. The aim of this study was to compare commercial tests for Chagas' disease serodiagnosis in southern Brazil. A total of 161 samples were evaluated. Three enzyme-linked immunosorbent assays, one indirect hemagglutination and one indirect immunofluorescence were assessed. Trypomastigote excreted-secreted antigen-blot was a confirmatory method. From 161 samples, 65.84% were positive in all tests, while 34.16% presents mismatch result in at least one of the tests. All techniques tested presented false-positive and/or false-negative results as follows: Enzyme-linked immunosorbent assay 1 had more false-positive results (lower specificity, indirect immunofluorescence had the highest rate of false-negative results (lower sen sitivity, enzyme-linked immunosorbent assays had fewer false-negative results (higher sensitivity, while indirect hemagglutination showed no false-positive result (higher specificity. Knowing the characteristics of techniques make it possible to combine them and obtain more reliable diagnosis. Therefore, it seems useful to combine techniques for diagnosing this infection.

  18. An angular fluidic channel for prism-free surface-plasmon-assisted fluorescence capturing

    Science.gov (United States)

    Nomura, Ken-Ichi; Gopinath, Subash C. B.; Lakshmipriya, Thangavel; Fukuda, Nobuko; Wang, Xiaomin; Fujimaki, Makoto

    2013-12-01

    Surface plasmon excitation provides stronger enhancement of the fluorescence intensity and better sensitivity than other sensing approaches but requires optimal positioning of a prism to ensure optimum output of the incident light. Here we describe a simple, highly sensitive optical sensing system combining surface plasmon excitation and fluorescence to address this limitation. V-shaped fluidic channels are employed to mimic the functions of a prism, sensing plate, and flow channel in a single setup. Superior performance is demonstrated for different biomolecular recognition reactions on a self-assembled monolayer, and the sensitivity reaches 100 fM for biotin-streptavidin interactions. Using an antibody as a probe, we demonstrate the detection of intact influenza viruses at 0.2 HA units ml-1 levels. The convenient sensing system developed here has the advantages of being prism-free and requiring less sample (1-2 μl), making this platform suitable for use in situations requiring low sample volumes.

  19. Structural analysis of β-prism lectin from Colocasia esculenta (L.) S chott.

    Science.gov (United States)

    Vajravijayan, S; Pletnev, S; Pletnev, V Z; Nandhagopal, N; Gunasekaran, K

    2016-10-01

    The Mannose-binding β-Prism Colocasia esculenta lectin (β-PCL) was purified from tubers using ion exchange chromatography. The purified β-PCL appeared as a single band of ∼12kDa on SDS-PAGE. β-PCL crystallizes in trigonal space group P3121 and diffracted to a resolution of 2.1Å. The structure was solved using Molecular replacement using Crocus vernus lectin (PDB: 3MEZ) as a model. From the final refined model to an R-factor of 16.5% and an Rfree of 20.4%, it has been observed that the biological unit consists of two β-Prism domains augmented through C-terminals swap over to form one of faces for each domain. Cα superposition of individual domains of β-PCL with individual domains of other related structures and superposition of whole protein structures were carried out. The higher RMS deviation for the superposition of whole structures suggest that β-prism domains assume different orientation in each structure.

  20. Deformation-induced diagenesis and microbial activity in the Nankai accretionary prism

    Science.gov (United States)

    Famin, V.; Andreani, M.; Boullier, A. M.; Raimbourg, H.; Magnin, V.

    2014-12-01

    We performed a microscopic and chemical study of diagenetic reactions in deformation microstructures within deep mud sediments from the Nankai accretionary prism (SW Japan) collected during IODP Expedition 315. Our study reveals that deformation microstructures localize the crystallization of pyrite, a diagenetic reaction also found in large megasplay faults of the prism. Textural observation shows that pyrite crystallization is synchronous of the sediment deformation. The framboidal shape of pyrite crystals, the barium depletion and the strong arsenic enrichment observed in deformation microstructures compared with the sediment matrix, suggest that pyrite crystallization is mediated by the proliferation of anoxic archae. During scientific drilling expeditions IODP 315, 316 and 319, microbial life has been evidenced at depths of up to 800 m below the sea floor by the presence of biogenic methane and sulfate reducers in sediments. We suggest that deformation structures localize microbial proliferation because the fracturing of silicate minerals produces hydrogen, a necessary compound for bacteria under anoxic conditions. Bacteria proliferate as long as active deformation supplies hydrogen, and vanish when the deformation stops. The development of bacteria in deformation structures impacts our mechanical understanding of fault zones in accretionary prisms: Firstly, bacterial activity converts carbon from organic matter and hydrogen into methane and/or water, which may alter the fluid budget of fault zones and the recurrence of dynamic ruptures in megathrusts. Secondly, the abundance of bacteria could be used to recognize active fault zones from inactive ones in drilling cores.

  1. Polarization properties in a prism laser gyro with mechanical dither bias

    Institute of Scientific and Technical Information of China (English)

    Yao Cheng-Kang; Zeng Xiao-Dong; Cao Chang-Qing

    2012-01-01

    Theoretical analysis and experimental research on the polarization properties of output light in gyro are carried out to investigate the phenomenon that the amplitude of an output voltage signal is modulated by dither bias in laser gyros consisting of totally reflecting prisms.Taking the effect of prism stress birefringence into account,an analytical formula of the output light intensity in the gyro and the relationship between the polarization parameter and the amplitude modulation of the output signal are obtained and discussed.For the first time,the polarized power value of the output light is adopted as a basis to estimate the output signal amplitude fading extent of laser gyros.Experimental results demonstrate that when the value of polarized power of output light is below 25.5% of that in ideal static case,the standard error is over 0.0337 dBm,and the displacement extent of the prism is higher than 53% of the radius of the beam waist in the gyro cavity,the amplitude modulation extent of gyro output signal can reach up to 16%,which badly influences the measurement accuracy of the laser gyro.Using this polarized power detecting measurement method can repair the gyro immediately during its fabrication process,improve the testing and production efficiency and shorten the product development cycle.

  2. Research on refractive index of optical cement used in Glan-Thompson prisms

    Institute of Scientific and Technical Information of China (English)

    Haifeng Wang; Fuquan Wu; Hailong Wang; Jing Wang; Shan Zhang

    2007-01-01

    The influence of the refractive index n2 of optical cement on the structure angle, field angle, and transmission of Glan-Thompson prism has been studied in detail. The results show that the structure angle will increase with the decrease of n2 under the condition of the largest field angle. Thus, the ratio of length to width (L/A) of the prism will decrease, which means more materials can be saved. When the value of L/A is 3.0 or 2.5 in the routine design, the field angle will firstly increase and then decrease with the increment of n2. Two routine designs with the n2 values of 1.47 and 1.45 have the optimal field angle. In addition, n2 also has great influence on light intensity transmittance of the prism. Considering all these factors, it will be the best choice with L/A=2.5 and n2 = 1.45 - 1.46.

  3. Structural analysis of β-prism lectin from Colocasia esculenta (L.) S chott.

    Science.gov (United States)

    Vajravijayan, S; Pletnev, S; Pletnev, V Z; Nandhagopal, N; Gunasekaran, K

    2016-10-01

    The Mannose-binding β-Prism Colocasia esculenta lectin (β-PCL) was purified from tubers using ion exchange chromatography. The purified β-PCL appeared as a single band of ∼12kDa on SDS-PAGE. β-PCL crystallizes in trigonal space group P3121 and diffracted to a resolution of 2.1Å. The structure was solved using Molecular replacement using Crocus vernus lectin (PDB: 3MEZ) as a model. From the final refined model to an R-factor of 16.5% and an Rfree of 20.4%, it has been observed that the biological unit consists of two β-Prism domains augmented through C-terminals swap over to form one of faces for each domain. Cα superposition of individual domains of β-PCL with individual domains of other related structures and superposition of whole protein structures were carried out. The higher RMS deviation for the superposition of whole structures suggest that β-prism domains assume different orientation in each structure. PMID:27262515

  4. Diamond-coated ATR prism for infrared absorption spectroscopy of surface-modified diamond nanoparticles

    International Nuclear Information System (INIS)

    Linear antenna microwave chemical vapor deposition process was used to homogeneously coat a 7 cm long silicon prism by 85 nm thin nanocrystalline diamond (NCD) layer. To show the advantages of the NCD-coated prism for attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) of nanoparticles, we apply diamond nanoparticles (DNPs) of 5 nm nominal size with various surface modifications by a drop-casting of their methanol dispersions. ATR-FTIR spectra of as-received, air-annealed, plasma-oxidized, and plasma-hydrogenated DNPs were measured in the 4000–1500 cm−1 spectral range. The spectra show high spectral resolution, high sensitivity to specific DNP surface moieties, and repeatability. The NCD coating provides mechanical protection against scratching and chemical stability of the surface. Moreover, unlike on bare Si surface, NCD hydrophilic properties enable optically homogeneous coverage by DNPs with some aggregation on submicron scale as evidenced by scanning electron microscopy and atomic force microscopy. Compared to transmission FTIR regime with KBr pellets, direct and uniform deposition of DNPs on NCD-ATR prism significantly simplifies and speeds up the analysis (from days to minutes). We discuss prospects for in situ monitoring of surface modifications and molecular grafting.

  5. Possibilities of magnet prism β-spectrometer application in on-line experiments

    International Nuclear Information System (INIS)

    The main attention is paid to works with particle beam in up-to-date nuclear investigations. The application of magnet prism β-spectrometer for works in 'on-line' experiments is considered in this article. The source chamber and detector chamber are distanted from each other on great distance (4 m) and are out of operation field of spectrometer. There is a reliable defence of operating field of device from external parasitic fields by the magnetic screens system. The additional advantage is a factor that source (target) and detector could replacing in specific directions about few centimetres during the device operating. The main β-spectroscopic performances of device are compared with Grenoble spectroscopic complex. The liner depression of prism spectrometer account for from 3,6 up to 6 m; light force - from 2·10-4 up to 6·10-4 up to 4π; operating resolving power - 0,02-0,05% by impulse. Investigation range is from several keV up to 3 MeV. There are all opportunities for installing of the on-line magnetic prism spectrometer on the U-150 accelerator and the WWR-K reactor. Spectrometer application in 'on-line' experiments gives possibility to obtain more wide information. 4 refs

  6. Standard neutron fields in graphite prism with Ra-α-Be source

    International Nuclear Information System (INIS)

    Neutron slowing-down and space-energy distribution of neutron flux in graphite prism with Ra-α-Be source were investigated experimentally, numerically and theoretically. Recent measurement and numerical experiment based on Monte Carlo calculations were carried out for the purpose of determining detailed space and energy distribution of neutron flux in the prism. Measurement of two-group neutron flux distribution along the central vertical axis of graphite prism was performed by irradiation of golden foils with cadmium covers and without them. Gamma and beta activities of foils were measured absolutely by using coaxial semiconductor germanium gamma detector and dual gas proportional alpha/beta detector, respectively. Starting from the results of numerical Monte Carlo experiment, neutron ages that enable analytical representation of neutron flux in broad energy intervals were determined. For the six chosen broad energy intervals the very good agreement between numerical experiment and Fermi age theory results was achieved with three age groups, corresponded source fractions and neutron ages. (author)

  7. Polarization properties in a prism laser gyro with mechanical dither bias

    International Nuclear Information System (INIS)

    Theoretical analysis and experimental research on the polarization properties of output light in gyro are carried out to investigate the phenomenon that the amplitude of an output voltage signal is modulated by dither bias in laser gyros consisting of totally reflecting prisms. Taking the effect of prism stress birefringence into account, an analytical formula of the output light intensity in the gyro and the relationship between the polarization parameter and the amplitude modulation of the output signal are obtained and discussed. For the first time, the polarized power value of the output light is adopted as a basis to estimate the output signal amplitude fading extent of laser gyros. Experimental results demonstrate that when the value of polarized power of output light is below 25.5% of that in ideal static case, the standard error is over 0.0337 dBm, and the displacement extent of the prism is higher than 53% of the radius of the beam waist in the gyro cavity, the amplitude modulation extent of gyro output signal can reach up to 16%, which badly influences the measurement accuracy of the laser gyro. Using this polarized power detecting measurement method can repair the gyro immediately during its fabrication process, improve the testing and production efficiency and shorten the product development cycle. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  8. Case-control study of factors associated with chronic Chagas heart disease in patients over 50 years of age

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    Silvana de Araújo Silva

    2007-11-01

    Full Text Available A case-control study on chronic Chagas heart disease (CCHD was carried out between 1997 and 2005. Ninety patients over 50 years of age were examined for factors related to (CCHD. Fourty-six patients (51.1% with Chagas heart disease (anomalous ECG were assigned to the case group and 44 (48.9% were included in the control group as carriers of undetermined forms of chronic disease. Social, demographic (age, gender, skin color, area of origin, epidemiological (permanence within an endemic zone, family history of Chagas heart disease or sudden death, physical strain, alcoholism, and smoking, and clinical (systemic hypertension variables were analyzed. The data set was assessed through single-variable and multivariate analysis. The two factors independently associated with heart disease were age - presence of heart disease being three times higher in patients over 60 years of age (odds ratio, OR: 2.89; confidence interval of 95%: 1.09-7.61 - and family history of Chagas heart disease (OR: 2.833, CI 95%: 1.11-7.23. Systemic hypertension and gender did not prove to hold any association with heart disease, as neither did skin color, but this variable showed low statistical power due to reduced sample size.

  9. Correlation between infection rate of triatominies and Chagas Disease in Southwest of Bahia, Brazil: a warning sign?

    Science.gov (United States)

    Silveira, Eliezer A DA; Ribeiro, Israel S; Amorim, Miguel S; Rocha, Dalva V; Coutinho, Helder S; Freitas, Leandro M DE; Tomazi, Laize; Silva, Robson A A DA

    2016-07-11

    Chagas disease, caused by the Trypanosoma cruzi, has a wide distribution in South America, and its main method of control is the elimination of triatomines. It is presented here the geographic distribution and the rate of natural infection by T. cruzi of triatomines collected and evaluated from 2008 to 2013 in southwest of Bahia. Triatomines were captured in the intradomiciliary and peridomiciliary areas of five cities located in the southwest of Bahia state, identified, and analyzed for the presence of trypanosomatids in their feces. During the study period the number of patients suspected for acute Chagas disease was recovered from the Notifiable Diseases Information System (SINAN). 8966 triatomines were captured and identified as belonging to eight species. Twenty-six presented themselves infected, being Triatoma sordida the most abundant and with the highest percentage of infection by T. cruzi. Tremedal was the city with the highest number of cases of acute Chagas' disease reported to SINAN. All cities showed triatomines infected with T. cruzi, so there is considerable risk of vectorial transmission of Chagas disease in the southwestern Bahia state, evidencing the need for vector transmission control programs and preventive surveillance measures. PMID:27411071

  10. Opportunities for improved chagas disease vector control based on knowledge, attitudes and practices of communities in the yucatan peninsula, Mexico.

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    Kathryn Rosecrans

    2014-03-01

    Full Text Available BACKGROUND: Chagas disease is a vector-borne parasitic disease of major public health importance. Current prevention efforts are based on triatomine vector control to reduce transmission to humans. Success of vector control interventions depends on their acceptability and value to affected communities. We aimed to identify opportunities for and barriers to improved vector control strategies in the Yucatan peninsula, Mexico. METHODOLOGY/PRINCIPAL FINDINGS: We employed a sequence of qualitative and quantitative research methods to investigate knowledge, attitudes and practices surrounding Chagas disease, triatomines and vector control in three rural communities. Our combined data show that community members are well aware of triatomines and are knowledgeable about their habits. However, most have a limited understanding of the transmission dynamics and clinical manifestations of Chagas disease. While triatomine control is not a priority for community members, they frequently use domestic insecticide products including insecticide spray, mosquito coils and plug-in repellents. Families spend about $32 US per year on these products. Alternative methods such as yard cleaning and window screens are perceived as desirable and potentially more effective. Screens are nonetheless described as unaffordable, in spite of a cost comparable to the average annual spending on insecticide products. CONCLUSION/SIGNIFICANCE: Further education campaigns and possibly financing schemes may lead families to redirect their current vector control spending from insecticide products to window screens. Also, synergism with mosquito control efforts should be further explored to motivate community involvement and ensure sustainability of Chagas disease vector control.

  11. Comparison of seven diagnostic tests to detect Trypanosoma cruzi infection in patients in chronic phase of Chagas disease

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    Luisa Fernanda Duarte

    2014-07-01

    Full Text Available Objective: To compare the diagnostic performance of seven methods to determine Trypanosoma cruzi infection in patients with chronic Chagas disease.Methods: Analytical study, using the case-control design, which included 205 people (patients with Chagasic cardiomyopathy, n= 100; control group, n= 105. Three enzyme linked immunosorbent assays, one indirect hemagglutination assay and one immunochromatographic test were assessed. Additionally, DNA amplification was performed via the PCR method using kinetoplast and nuclear DNA as target sequences. For the comparative analysis of diagnostic tests, the parameters used were sensitivity, specificity, positive and negative predictive values, Receiver Operator Characteristic (ROC, positive and negative likelihood ratio, as well as κ quality analysis.Results: The commercial Bioelisa Chagas test showed the highest sensitivity (98%, specificity (100%, and positive and negative predictive values; additionally it had the highest discriminatory power. Otherwise, the amplification of T. cruzi DNA in blood samples showed low values of sensitivity (kinetoplast DNA= 51%, nuclear DNA= 22%, but high values of specificity (100%, and moderate to low discriminatory ability.Conclusion: The comparative analysis among the different methods suggests that the diagnostic strategy of T. cruzi infection in patients with chronic Chagas disease can be performed using ELISA assays based on recombinant proteins and/or synthetic peptides, which show higher diagnosis performance and can confirm and exclude the diagnosis of T. cruzi infection. The molecular methods show poor performance when used in the diagnosis of patients with chronic Chagas disease.

  12. ONE-DIMENSIONAL LIGHT BEAM WIDENING USING PRISMS FOR INCREASE OF SPECTROMETER SPECTRAL RESOLUTION AND ANGULAR DISPERSION

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    I. M. Gulis

    2016-01-01

    Full Text Available The increase of angular dispersion and slit resolution limit of grating spectrometers by means of variation of grating parameters is limited by its period and allowable order of diffraction. The special solutions (echelle, holographic, immersion gratings are acceptable in a limited parameter range and are technologically complex in fabrication, thus hardly applicable to instruments of mass production. We propose to decrease slit resolution limit by one-dimensional beam widening in dispersion plane by means of passing it through oblique prism before incidence onto diffraction grating. The increase of angular dispersion can be achieved by narrowing of dispersed beams after grating while passing through other oblique prism. We prove that slit resolution limit in such a system changes approximately as multiplied by angular magnification of the first prism (that is less than 1 times. Also angular dispersion changed approximately as multiplied by angular magnification of the second prism. The Fresnel reflection from the faces of prisms is analyzed. Accounting for that factor gives the increase of resolution about 1,4–1,6 times without loss of light (and can be 2 and more times while using anti-reflective coating. The proposed method is different from the similar ones first of all by its simplicity because it uses simple optical elements – plane reflective grating and thin prisms. It can be applied to amend the analytical characteristics of dispersive spectrometers, first of all the small-sized ones. 

  13. A single blinded randomised controlled pilot trial of prism adaptation for improving self-care in stroke patients with neglect.

    Science.gov (United States)

    Turton, Ailie J; O'Leary, Kelly; Gabb, Judith; Woodward, Rebecca; Gilchrist, Iain D

    2010-04-01

    Prism adaptation has been shown to alleviate the symptoms of unilateral spatial neglect following stroke in single case and small group studies. The purposes of this single blinded pilot randomised controlled trial were to determine the feasibility of delivering prism adaptation treatment in a clinically valid sample and to assess its impact on self-care. Thirty seven right hemisphere stroke patients with unilateral spatial neglect were randomised into either prism adaptation (using 10 dioptre, 6 degree prisms) or sham treatment (using plain glasses) groups. Treatment was delivered each weekday for two weeks. Pointing accuracy, without vision of the finger, was recorded each day before treatment. Outcome was measured, by blinded assessors, four days and eight weeks after the end of treatment using the Catherine Bergego Scale (CBS) and the conventional neuropsychological tests from the Behavioural Inattention Test (BIT). Thirty four patients received treatment: 16 with prisms, 18 sham. Mean compliance was 99% and 97%, respectively. Over the treatment days only the prism treated group showed increased leftward bias in open loop pointing to targets on a touch screen. However, despite the group level changes in pointing behaviour no overall effect of the treatment on self-care or BIT were found.

  14. Chagas disease: current epidemiological trends after the interruption of vectorial and transfusional transmission in the Southern Cone countries.

    Science.gov (United States)

    Moncayo, Alvaro

    2003-07-01

    Chagas disease, named after Carlos Chagas who first described it in 1909, exists only on the American Continent. It is caused by a parasite, Trypanosoma cruzi, transmitted to humans by blood-sucking triatomine bugs and by blood transfusion. Chagas disease has two successive phases, acute and chronic. The acute phase lasts 6 to 8 weeks. After several years of starting the chronic phase, 20% to 35% of the infected individuals, depending on the geographical area will develop irreversible lesions of the autonomous nervous system in the heart, esophagus, colon and the peripheral nervous system. Data on the prevalence and distribution of Chagas disease improved in quality during the 1980's as a result of the demographically representative cross-sectional studies carried out in countries where accurate information was not available. A group of experts met in Bras lia in 1979 and devised standard protocols to carry out countrywide prevalence studies on human T. cruzi infection and triatomine house infestation. Thanks to a coordinated multi-country program in the Southern Cone countries the transmission of Chagas disease by vectors and by blood transfusion has been interrupted in Uruguay in1997, in Chile in 1999, and in 8 of the 12 endemic states of Brazil in 2000 and so the incidence of new infections by T. cruzi in the whole continent has decreased by 70%. Similar control multi-country initiatives have been launched in the Andean countries and in Central America and rapid progress has been recorded to ensure the interruption of the transmission of Chagas disease by 2005 as requested by a Resolution of the World Health Assembly approved in 1998. The cost-benefit analysis of the investments of the vector control program in Brazil indicate that there are savings of US$17 in medical care and disabilities for each dollar spent on prevention, showing that the program is a health investment with good return. Since the inception in 1979 of the Steering Committee on Chagas Disease

  15. Longitudinal study of patients with chronic Chagas cardiomyopathy in Brazil (SaMi-Trop project): a cohort profile

    Science.gov (United States)

    Cardoso, Clareci Silva; Sabino, Ester Cerdeira; Oliveira, Claudia Di Lorenzo; de Oliveira, Lea Campos; Ferreira, Ariela Mota; Cunha-Neto, Edécio; Bierrenbach, Ana Luiza; Ferreira, João Eduardo; Haikal, Desirée Sant'Ana; Reingold, Arthur L; Ribeiro, Antonio Luiz P

    2016-01-01

    Purpose We have established a prospective cohort of 1959 patients with chronic Chagas cardiomyopathy to evaluate if a clinical prediction rule based on ECG, brain natriuretic peptide (BNP) levels, and other biomarkers can be useful in clinical practice. This paper outlines the study and baseline characteristics of the participants. Participants The study is being conducted in 21 municipalities of the northern part of Minas Gerais State in Brazil, and includes a follow-up of 2 years. The baseline evaluation included collection of sociodemographic information, social determinants of health, health-related behaviours, comorbidities, medicines in use, history of previous treatment for Chagas disease, functional class, quality of life, blood sample collection, and ECG. Patients were mostly female, aged 50–74 years, with low family income and educational level, with known Chagas disease for >10 years; 46% presented with functional class >II. Previous use of benznidazole was reported by 25.2% and permanent use of pacemaker by 6.2%. Almost half of the patients presented with high blood cholesterol and hypertension, and one-third of them had diabetes mellitus. N-terminal of the prohormone BNP (NT-ProBNP) level was >300 pg/mL in 30% of the sample. Findings to date Clinical and laboratory markers predictive of severe and progressive Chagas disease were identified as high NT-ProBNP levels, as well as symptoms of advanced heart failure. These results confirm the important residual morbidity of Chagas disease in the remote areas, thus supporting political decisions that should prioritise in addition to epidemiological surveillance the medical treatment of chronic Chagas cardiomyopathy in the coming years. The São Paulo-Minas Gerais Tropical Medicine Research Center (SaMi-Trop) represents a major challenge for focused research in neglected diseases, with knowledge that can be applied in primary healthcare. Future plans We will continue following this patients’ cohort

  16. Epidemiología de la enfermedad de Chagas en el estado de Veracruz Epidemiology of Chagas disease in the state of Veracruz

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    Elsa L Segura

    2005-06-01

    Full Text Available OBJETIVO: Identificar la seroprevalencia de enfermedad de Chagas, los factores de riesgo de la vivienda e índices entomológicos, para proponer medidas de control en 11 jurisdicciones sanitarias del estado de Veracruz. MATERIAL Y MÉTODOS: Entre 1997 y 2001 se hizo un estudio transversal cuya muestra quedó integrada por 281 localidades, 2 526 viviendas y 9 782 individuos. Se aplicó un cuestionario sobre factores de riesgo, se tomó sangre en papel filtro y se buscaron triatominos en el intra y peridomicilio. Se obtuvo la prevalencia de exposición a factores de riesgo y de seropositividad para la enfermedad. Se hizo análisis bivariado mediante la razón de momios, ji de Mantel y Haenszel e intervalo de confianza a 95% como prueba de significancia estadística. El análisis multivariado se hizo mediante la regresión logística no condicional y se incluyeron las variables que durante el análisis bivariado mostraron un valor de p hasta de 0.20. El impacto potencial se estimó con base en la fracción etiológica en expuestos. RESULTADOS: La prevalencia de enfermedad de Chagas fluctuó entre 0 y 2.8%. Las jurisdicciones con mayor riesgo fueron Tuxpan, Pánuco y Córdoba, y sin riesgo, Orizaba. Los principales factores de riesgo de la vivienda fueron el techo y muro de palma/zacate y piso de tierra, así como la presencia del vector y la ventilación. CONCLUSIONES: Es necesario realizar vigilancia epidemiológica basada en educación para la salud, mejoramiento de la vivienda y uso de insecticidas.OBJECTIVE: To assess the seroprevalence, household risk factors, and entomological indicators, in order to frame control measures in 11 Sanitary Jurisdictions of the state. MATERIAL AND METHODS: This study included 281 towns, 2 526 households, and 9782 individuals. Data were collected using a questionnaire. Blood was obtained in filter paper and a search for triatomines was conducted inside of and around dwellings. Prevalence rates were used to

  17. Globalização, iniqüidade e doença de Chagas Globalization, inequity and Chagas disease

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    João Carlos Pinto Dias

    2007-01-01

    Full Text Available A doença de Chagas (tripanossomíase americana, apresenta múltiplos aspectos sócio-culturais e político-econômicos que envolvem questões de iniqüidade e globalização. São relações presentes tanto nos processos de produção da doença como nas possibilidades de sua prevenção e manejo. Apesar da pobreza da região, envolvendo questões de iniqüidade e globalização, a doença tem sido controlada em várias áreas, o que reforça a auto-estima dos países. Para o futuro, problemas e desafios podem ser esperados, principalmente em termos da assistência médica para os indivíduos já infectados e da sustentação de uma vigilância epidemiológica permanente. Ambos estes pontos dependem de um melhor desempenho dos sistemas nacionais de saúde, principalmente em termos de sua competência e da superação de situações de iniqüidade. Particularmente, tem cabido à comunidade científica e acadêmica latino-americana um papel de grande destaque na implementação e sustentação de políticas de controle da doença, que hoje evoluíram para estratégias de ação compartida entre países, o que pode significar importante avanço no contexto político da região.Chagas disease (American trypanosomiasis bears a close relationship to multiple social and political aspects involving issues of globalization and inequity. Such relations concern the process of disease production and control in parallel with medical management. Despite the poverty in Latin America and various problems related to inequities and globalization, Chagas disease has been controlled in several areas, a fact that reinforces the countries' self-reliance. Several problems and challenges related to the disease can be expected in the future, mainly concerning medical care for already infected individuals and the sustainability of effective epidemiological surveillance. Both points depend heavily on improved performance by the national health systems, principally in

  18. Histological and endoscopic features of the stomachs of patients with Chagas disease in the era of Helicobacter pylori

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    Fernanda Machado Fonseca

    2014-12-01

    Full Text Available Introduction Most studies that have evaluated the stomachs of patients with Chagas disease were performed before the discovery of Helicobacter pylori and used no control groups. This study compared the gastric features of chagasic and non-chagasic patients and assessed whether gastritis could be associated with Chagas disease. Methods Gastric biopsy samples were taken from patients who underwent endoscopy for histological analysis according to the Updated Sydney System. H. pylori infection was assessed by histology, 16S ribosomal ribonucleic acid (rRNA polymerase chain reaction (PCR, serology and the 13C-urea breath test. Patients were considered H. pylori-negative when all of these diagnostic tests were negative. Clinical and socio-demographic data were obtained by reviewing medical records and using a questionnaire. Results The prevalence of H. pylori infection (70.3% versus 71.7% and chronic gastritis (92.2% versus 85% was similar in the chagasic and non-chagasic groups, respectively; such as peptic ulcer, atrophy and intestinal metaplasia. Gastritis was associated with H. pylori infection independent of Chagas disease in a log-binomial regression model. However, the chagasic H. pylori-negative patients showed a significantly higher grade of mononuclear (in the corpus and polymorphonuclear (PMN (in the antrum cell infiltration. Additionally, the patients with the digestive form of Chagas disease showed a significantly lower prevalence of corpus atrophy than those with other clinical forms. Conclusions The prevalence of H. pylori infection and of gastric histological and endoscopic features was similar among the chagasic and non-chagasic patients. Additionally, this is the first controlled study to demonstrate that H. pylori is the major cause of gastritis in patients with Chagas disease.

  19. Lineage analysis of circulating Trypanosoma cruzi parasites and their association with clinical forms of Chagas disease in Bolivia.

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    Ramona del Puerto

    Full Text Available BACKGROUND: The causative agent of Chagas disease, Trypanosoma cruzi, is divided into 6 Discrete Typing Units (DTU: Tc I, IIa, IIb, IIc, IId and IIe. In order to assess the relative pathogenicities of different DTUs, blood samples from three different clinical groups of chronic Chagas disease patients (indeterminate, cardiac, megacolon from Bolivia were analyzed for their circulating parasites lineages using minicircle kinetoplast DNA polymorphism. METHODS AND FINDINGS: Between 2000 and 2007, patients sent to the Centro Nacional de Enfermedades Tropicales for diagnosis of Chagas from clinics and hospitals in Santa Cruz, Bolivia, were assessed by serology, cardiology and gastro-intestinal examinations. Additionally, patients who underwent colonectomies due to Chagasic magacolon at the Hospital Universitario Japonés were also included. A total of 306 chronic Chagas patients were defined by their clinical types (81 with cardiopathy, 150 without cardiopathy, 100 with megacolon, 144 without megacolon, 164 with cardiopathy or megacolon, 73 indeterminate and 17 cases with both cardiopathy and megacolon. DNA was extracted from 10 ml of peripheral venous blood for PCR analysis. The kinetoplast minicircle DNA (kDNA was amplified from 196 out of 306 samples (64.1%, of which 104 (53.3% were Tc IId, 4 (2.0% Tc I, 7 (3.6% Tc IIb, 1 (0.5% Tc IIe, 26 (13.3% Tc I/IId, 1 (0.5% Tc I/IIb/IId, 2 (1.0% Tc IIb/d and 51 (25.9% were unidentified. Of the 133 Tc IId samples, three different kDNA hypervariable region patterns were detected; Mn (49.6%, TPK like (48.9% and Bug-like (1.5%. There was no significant association between Tc types and clinical manifestations of disease. CONCLUSIONS: None of the identified lineages or sublineages was significantly associated with any particular clinical manifestations in the chronic Chagas patients in Bolivia.

  20. Polymorphic sites at the immunoregulatory CTLA-4 gene are associated with chronic chagas disease and its clinical manifestations.

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    Fabrício C Dias

    Full Text Available BACKGROUND: Chagas disease affects approximately 10 million people mainly in Latin America. The immune regulation by the host seems to be an essential factor for disease evolution, and immune system inhibitory molecules such as CTLA-4 and PD-1 favor the maintenance of peripheral tolerance. Considering that polymorphisms at the immunoregulatory CTLA-4 and PDCD1 genes may alter their inhibitory function, we investigated the association of alleles, genotypes and haplotypes of polymorphic sites observed at the CTLA-4 and PDCD1 genes with different clinical manifestations of chronic Chagas disease (indeterminate, cardiac, digestive and mixed. METHODS: The polymorphisms at the CTLA-4 (-1722T/C, -318C/T and +49A/G and PDCD1 (PD-1.3G/A genes were typed using TaqMan methodology in 277 chronic Chagas disease patients classified into four groups, according to clinical characteristics, and 326 non-infected controls. RESULTS: Our results showed that CTLA-4 -1722CC genotype (22%, -1722C allele (27% and CTLA-4 TCG (8.6%, TCA (26% and CCA (15% haplotypes were strongly associated with the indeterminate form, while the CTLA-4-318CT genotype (82% and CTLA-4-318T allele (47% were found mainly in patients with the mixed form of the disease. The CTLA-4 TCG haplotype (10.2% was associated with the digestive form. On the other hand, the PD-1.3G/A polymorphism was not associated with chronic Chagas disease and its clinical manifestations. CONCLUSIONS: Here, we showed that alleles, genotypes and haplotypes reported to increase the expression of the regulatory molecule CTLA-4 were associated with the indeterminate form of the disease. Taken together, our data support the idea that polymorphic sites at immunoregulatory genes may influence the development of Chagas disease variants.