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Sample records for praziquantel em uma

  1. Praziquantel

    MedlinePlus

    Praziquantel is used to treat schistosoma (infection with a type of worm that lives in the bloodstream) ... worm that lives in or near the liver). Praziquantel is in a class of medications called anthelmintics. ...

  2. 21 CFR 520.1870 - Praziquantel tablets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Praziquantel tablets. 520.1870 Section 520.1870... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1870 Praziquantel tablets. (a) Specifications. Each tablet contains: (1) 34 milligrams (mg) praziquantel. (2) 11.5 or 23 mg praziquantel....

  3. 21 CFR 520.1870 - Praziquantel tablets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Praziquantel tablets. 520.1870 Section 520.1870... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1870 Praziquantel tablets. (a) Specifications. Each tablet contains: (1) 34 milligrams (mg) praziquantel. (2) 11.5 or 23 mg praziquantel....

  4. 21 CFR 520.1870 - Praziquantel tablets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Praziquantel tablets. 520.1870 Section 520.1870... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1870 Praziquantel tablets. (a) Specifications. Each tablet contains: (1) 34 milligrams (mg) praziquantel. (2) 11.5 or 23 mg praziquantel....

  5. 21 CFR 520.1870 - Praziquantel tablets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Praziquantel tablets. 520.1870 Section 520.1870... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1870 Praziquantel tablets. (a) Specifications. Each tablet contains: (1) 34 milligrams (mg) praziquantel. (2) 11.5 or 23 mg praziquantel....

  6. Praziquantel, Mefloquine-Praziquantel, and Mefloquine-Artesunate-Praziquantel against Schistosoma haematobium: A Randomized, Exploratory, Open-Label Trial

    PubMed Central

    Keiser, Jennifer; Silué, Kigbafori D.; Adiossan, Lukas K.; N'Guessan, Nicaise A.; Monsan, N'Chou; Utzinger, Jürg; N'Goran, Eliézer K.

    2014-01-01

    Background Treatment and morbidity control of schistosomiasis relies on a single drug, praziquantel. Hence, there is a pressing need to develop additional therapeutics against schistosomiasis. The antimalarial drug mefloquine shows antischistosomal activity in animal models and clinical trials, which calls for further investigations. Methodology We comparatively assessed the efficacy and tolerability of the following treatments against Schistosoma haematobium in school-aged children in Côte d'Ivoire: (i) praziquantel (40 mg/kg; standard treatment); (ii) mefloquine (25 mg/kg) combined with praziquantel (40 mg/kg); and (iii) mefloquine-artesunate (3× (100 mg artesunate +250 mg mefloquine)) combined with praziquantel (40 mg/kg) (treatments administered on subsequent days). Two urine samples were collected before, and on days 21–22 and 78–79 after the first dosing. Principal Findings Sixty-one children were present on all examination time points and had complete datasets. No difference in efficacy was observed between the three treatment groups on either follow-up. On the 21–22 day posttreatment follow-up, based on available case analysis, cure rates of 33% (95% confidence interval (CI) 11–55%), 29% (95% CI 8–50%), and 26% (95% CI 5–48%) were observed for praziquantel, mefloquine-artesunate-praziquantel, and mefloquine-praziquantel, respectively. The corresponding egg reduction rates were 94% and above. On the second follow-up, observed cure rates ranged from 19% (praziquantel) to 33% (mefloquine-artesunate-praziquantel), and egg reduction rates were above 90%. Praziquantel monotherapy was the best tolerated treatment. In the mefloquine-artesunate-praziquantel group, adverse events were reported by 91% of the participants, and in the mefloquine-praziquantel group, 95% experienced adverse events. With the exception of abdominal pain at moderate severity, adverse events were mild. Conclusions/Significance The addition of mefloquine or mefloquine

  7. Praziquantel inhibits Schistosoma mansoni attachment in vitro.

    PubMed

    da-Silva, S P; Noel, F

    1990-01-01

    Male adult Schistosoma mansoni worms were placed in a glass dish containing Tyrode solution and observed for 15 min after addition of praziquantel (0.01 to 1 microM). Praziquantel promoted a concentration- and time-dependent inhibition of sucker-mediated attachment of the worm. Attachment inhibition was correlated with shortening of the parasite. We propose that the rapid and total inhibition of worm attachment observed in vitro with 1 microM praziquantel indicates that therapeutic concentrations of this drug should promote a rapid hepatic shift, in vivo, which may facilitate host tissue reaction. PMID:2101049

  8. Uma grade de perfis teóricos para estrelas massivas em transição

    NASA Astrophysics Data System (ADS)

    Nascimento, C. M. P.; Machado, M. A.

    2003-08-01

    Na XXVIII Reunião Anual da Sociedade Astronômica Brasileira (2002) apresentamos uma grade de perfis calculados de acordo com os pontos da trajetória evolutiva de metalicidade solar, Z = 0.02 e taxa de perda de massa () padrão, para estrelas com massa inicial de 25, 40, 60, 85 e 120 massas solares. Estes perfis foram calculados com o auxílio de um código numérico adequado para descrever os ventos de objetos massivos, supondo simetria esférica, estacionaridade e homogeneidade. No presente trabalho, apresentamos a complementação da grade com os perfis teóricos relativos às trajetórias de Z = 0.02 com taxa de perda de massa dobrada em relação a padrão (2´), e de metalicidade Z = 0.008. Para cada ponto das três trajetórias obtemos os perfis teóricos de Ha, Hb, Hg e Hd, e como esperado eles se apresentam em pura emissão, pura absorção ou em P-Cygni. Para valores de taxa de perda de massa muito baixos (~10-7) não há formação de linhas, o que é visto nos primeiros pontos em todas as trajetórias. Em geral, para um mesmo ponto a componente de emissão diminui e a absorção aumenta de Ha para Hd. É verificado que as trajetórias com Z = 0.02 e padrão possuem menos circuitos (loops) do que as com metalicidade Z = 0.02 e 2´ padrão, e seus perfis são, em geral, menos intensos. Em relação a trajetória de Z = 0.008, verifica-se menos circuitos e maior variação em luminosidade, e seus perfis mostram-se em, algumas trajetórias, mais intensos. Verificamos também que, pontos distintos em uma mesma trajetória, apresentam perfis diferentes para valores similares de luminosidade e temperatura efetiva. Sendo assim, uma grade de perfis teóricos parece ser útil para fornecer uma informação preliminar sobre o estágio evolutivo de uma estrela massiva.

  9. Praziquantel

    MedlinePlus

    ... used to treat certain other worm infestations, including tapeworm (a type of worm that may attach to ... have ocular cysticercosis (infestation with a type of tapeworm that forms cysts in the eyes)Your doctor ...

  10. 21 CFR 520.903d - Febantel-praziquantel paste.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...-praziquantel paste. (a) Specifications. Each gram of paste contains 34 milligrams of febantel and 3.4... praziquantel per kilogram of body weight (1 gram of paste per 7.5 pounds body weight) administered by mouth or... milligrams of febantel and 1.5 milligrams of praziquantel per kilogram of body weight (1 gram of paste per...

  11. 21 CFR 522.1870 - Praziquantel injectable solution.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Praziquantel injectable solution. 522.1870 Section 522.1870 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... § 522.1870 Praziquantel injectable solution. (a) Specification. Each milliliter contains 56.8...

  12. 21 CFR 522.1870 - Praziquantel injectable solution.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Praziquantel injectable solution. 522.1870 Section 522.1870 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... § 522.1870 Praziquantel injectable solution. (a) Specification. Each milliliter contains 56.8...

  13. 21 CFR 520.1453 - Moxidectin and praziquantel gel.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Moxidectin and praziquantel gel. 520.1453 Section 520.1453 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... and praziquantel gel. (a) Specifications. Each milliliter of gel contains 20 milligrams (mg)...

  14. 21 CFR 520.1199 - Ivermectin, pyrantel, and praziquantel tablets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ivermectin, pyrantel, and praziquantel tablets... Ivermectin, pyrantel, and praziquantel tablets. (a) Specifications. Each chewable tablet contains: (1) 34...) Amount. Administer monthly according to body weight as follows: (i) 6 to 12 lb: one tablet as...

  15. 21 CFR 520.1199 - Ivermectin, pyrantel, and praziquantel tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ivermectin, pyrantel, and praziquantel tablets... Ivermectin, pyrantel, and praziquantel tablets. (a) Specifications. Each chewable tablet contains: (1) 34...) Amount. Administer monthly according to body weight as follows: (i) 6 to 12 lb: one tablet as...

  16. 21 CFR 520.1200 - Ivermectin, fenbendazole, and praziquantel tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ivermectin, fenbendazole, and praziquantel tablets... Ivermectin, fenbendazole, and praziquantel tablets. (a) Specifications. Each chewable tablet contains either... § 510.600(c) of this chapter. (c) Conditions of use in dogs—(1) Amount. Administer tablets to provide...

  17. 21 CFR 520.1200 - Ivermectin, fenbendazole, and praziquantel tablets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ivermectin, fenbendazole, and praziquantel tablets... Ivermectin, fenbendazole, and praziquantel tablets. (a) Specifications. Each chewable tablet contains either... § 510.600(c) of this chapter. (c) Conditions of use in dogs—(1) Amount. Administer tablets to provide...

  18. 21 CFR 520.1199 - Ivermectin, pyrantel, and praziquantel tablets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ivermectin, pyrantel, and praziquantel tablets... Ivermectin, pyrantel, and praziquantel tablets. (a) Specifications. Each chewable tablet contains: (1) 34...) Amount. Administer monthly according to body weight as follows: (i) 6 to 12 lb: one tablet as...

  19. 21 CFR 520.1199 - Ivermectin, pyrantel, and praziquantel tablets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ivermectin, pyrantel, and praziquantel tablets... Ivermectin, pyrantel, and praziquantel tablets. (a) Specifications. Each chewable tablet contains: (1) 34...) Amount. Administer monthly according to body weight as follows: (i) 6 to 12 lb: one tablet as...

  20. 21 CFR 520.1199 - Ivermectin, pyrantel, and praziquantel tablets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ivermectin, pyrantel, and praziquantel tablets... Ivermectin, pyrantel, and praziquantel tablets. (a) Specifications. Each chewable tablet contains: (1) 34...) Amount. Administer monthly according to body weight as follows: (i) 6 to 12 lb: one tablet as...

  1. 21 CFR 520.1200 - Ivermectin, fenbendazole, and praziquantel tablets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ivermectin, fenbendazole, and praziquantel tablets... Ivermectin, fenbendazole, and praziquantel tablets. (a) Specifications. Each chewable tablet contains either... § 510.600(c) of this chapter. (c) Conditions of use in dogs—(1) Amount. Administer tablets to provide...

  2. 21 CFR 520.1200 - Ivermectin, fenbendazole, and praziquantel tablets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ivermectin, fenbendazole, and praziquantel tablets... Ivermectin, fenbendazole, and praziquantel tablets. (a) Specifications. Each chewable tablet contains either... § 510.600(c) of this chapter. (c) Conditions of use in dogs—(1) Amount. Administer tablets to provide...

  3. 21 CFR 520.1200 - Ivermectin, fenbendazole, and praziquantel tablets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ivermectin, fenbendazole, and praziquantel tablets... Ivermectin, fenbendazole, and praziquantel tablets. (a) Specifications. Each chewable tablet contains either... § 510.600(c) of this chapter. (c) Conditions of use in dogs—(1) Amount. Administer tablets to provide...

  4. 21 CFR 522.1870 - Praziquantel injectable solution.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Praziquantel injectable solution. 522.1870 Section 522.1870 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1870 Praziquantel injectable...

  5. In vitro uptake of /sup 14/C-praziquantel by cestodes, trematodes, and a nematode

    SciTech Connect

    Andrews, P.; Thomas, H.; Weber, H.

    1980-12-01

    /sup 14/C-praziquantel was rapidly taken up by Schistosoma mansoni, Fasciola hepatica, Hymenolepis nana, and isolated strobilocerci of Taenia taeniaeformis. Schistosoma mansoni lost praziquantel rapidly to drug-free medium. Chromatography of extracts prepared after incubation of S. mansoni and H. nana yielded no indication that praziquantel was metabolized. Autoradiography revealed a uniform distribution of praziquantel throughout the tissues of S. mansoni and H. nana. Uptake was considerably slower in the nematode Heterakis spumosa and apparently via the oral route.

  6. Acute toxicity of praziquantel (an anthelmintic) to grass carp and golden shiners

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Praziquantel is an anthelmintic that can be applied to the water to kill tapeworm and trematode parasites in fish. Effective praziquantel treatment rates have been determined but there is little information on the toxicity of this chemical to fish hosts of the parasites. Acute praziquantel toxicit...

  7. The cytotoxicity study of praziquantel enantiomers

    PubMed Central

    Sun, Qian; Mao, Ruifeng; Wang, Dongling; Hu, Changyan; Zheng, Yang; Sun, Dequn

    2016-01-01

    Praziquantel (PZQ) is prescribed as a racemic mixture (racemic-PZQ, rac-PZQ), which is composed of (R)-PZQ and (S)-PZQ. In this work, the cytotoxicity of rac-PZQ and its two enantiomers (R)-PZQ and (S)-PZQ on eight cell lines (L-02, HepG2, prf-plc-5, SH-SY5Y, HUVEC, A549, HCT-15, Raw264.7) was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphe-nyltetrazolium bromide and lactate dehydrogenase assays. The morphology of apoptotic cells was studied by fluorescence microscope using Hoechst 33342 staining, and the cytotoxicity of the compounds was also tested by lactate dehydrogenase assay. Results revealed that (R)-PZQ had negligible cytotoxicity against L-02, SH-SY5Y, HUVEC, A549, HCT-15, and Raw264.7 cells but selectively inhibited tumor cell lines (prf-plc-5 and HepG2). However, in contrast to (R)-PZQ, the (S)-isomer showed higher cytotoxicity against L-02 cells and lower inhibition on prf-plc-5 and HepG2 cells. Besides, (R)-PZQ showed lower cytotoxicity on SH-SY5Y cells than (S)-PZQ. Meanwhile, (R)-PZQ at <80 μM concentration could promote proliferation of macrophage cells (Raw264.7). Our research revealed that (R)-PZQ has lower cytotoxicity than (S)-PZQ and has similar cytotoxicity with rac-PZQ. (S)-PZQ is the principal enantiomer to cause side effects on human definitive hosts. These findings gave the reasonable reasons for World Health Organization to produce (R)-PZQ as a replacement for rac-PZQ for the treatment of schistosomiasis. PMID:27445457

  8. The cytotoxicity study of praziquantel enantiomers.

    PubMed

    Sun, Qian; Mao, Ruifeng; Wang, Dongling; Hu, Changyan; Zheng, Yang; Sun, Dequn

    2016-01-01

    Praziquantel (PZQ) is prescribed as a racemic mixture (racemic-PZQ, rac-PZQ), which is composed of (R)-PZQ and (S)-PZQ. In this work, the cytotoxicity of rac-PZQ and its two enantiomers (R)-PZQ and (S)-PZQ on eight cell lines (L-02, HepG2, prf-plc-5, SH-SY5Y, HUVEC, A549, HCT-15, Raw264.7) was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphe-nyltetrazolium bromide and lactate dehydrogenase assays. The morphology of apoptotic cells was studied by fluorescence microscope using Hoechst 33342 staining, and the cytotoxicity of the compounds was also tested by lactate dehydrogenase assay. Results revealed that (R)-PZQ had negligible cytotoxicity against L-02, SH-SY5Y, HUVEC, A549, HCT-15, and Raw264.7 cells but selectively inhibited tumor cell lines (prf-plc-5 and HepG2). However, in contrast to (R)-PZQ, the (S)-isomer showed higher cytotoxicity against L-02 cells and lower inhibition on prf-plc-5 and HepG2 cells. Besides, (R)-PZQ showed lower cytotoxicity on SH-SY5Y cells than (S)-PZQ. Meanwhile, (R)-PZQ at <80 μM concentration could promote proliferation of macrophage cells (Raw264.7). Our research revealed that (R)-PZQ has lower cytotoxicity than (S)-PZQ and has similar cytotoxicity with rac-PZQ. (S)-PZQ is the principal enantiomer to cause side effects on human definitive hosts. These findings gave the reasonable reasons for World Health Organization to produce (R)-PZQ as a replacement for rac-PZQ for the treatment of schistosomiasis. PMID:27445457

  9. In vitro characterization of some biopharmaceutical properties of praziquantel.

    PubMed

    González-Esquivel, Dinora; Rivera, Julio; Castro, Nelly; Yepez-Mulia, Lilian; Jung Cook, Helgi

    2005-05-13

    In several studies of patients with neurocysticercosis under treatment with praziquantel (PZQ), the pharmacokinetic data were difficult to interpret probably because of the low solubility as well as its variable oral bioavailability. Because there is limited information available regarding the biopharmaceutical properties of PZQ, the aim of this work was to evaluate the absorption characteristics of the drug and its dissolution behaviour in simulated media. Additionally, its in vitro protein binding and displacement by highly bound drugs was evaluated. Permeability evaluation was carried out by using Caco-2 cells. Dissolution release profiles were evaluated using the USP apparatus and the following dissolution media: HCl containing 2mg of sodium laurylsulfate per milliliter, milk, FeSSIF and FaSSIF. Protein binding of PZQ was carried out by equilibrium dialysis. Results showed that praziquantel was absorbed by passive diffusion. The apparent permeability constant value was 4.4x10(-5) cm/s. Binding was not influenced by the addition of highly bound drugs. Dissolution from a tablet formulation showed that the rate of praziquantel was dependent on the components of the media. Although the simulated media could explain the influence of the lipids on praziquantel absorption, they were not able to forecast the influence of carbohydrates. Further refinements are required to explain the in vivo data. PMID:15847994

  10. 21 CFR 524.775 - Emodepside and praziquantel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Emodepside and praziquantel. 524.775 Section 524.775 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS §...

  11. Praziquantel degradation in marine aquarium water

    PubMed Central

    Dawson, Matthew R.; Ellis, Helen; Stamper, M. Andrew

    2016-01-01

    Praziquantel (PZQ) is a drug commonly utilized to treat both human schistosomiasis and some parasitic infections and infestations in animals. In the aquarium industry, PZQ can be administered in a “bath” to treat the presence of ectoparasites on both the gills and skin of fish and elasmobranchs. In order to fully treat an infestation, the bath treatment has to maintain therapeutic levels of PZQ over a period of days or weeks. It has long been assumed that, once administered, PZQ is stable in a marine environment throughout the treatment interval and must be mechanically removed, but no controlled experiments have been conducted to validate that claim. This study aimed to determine if PZQ would break down naturally within a marine aquarium below its 2 ppm therapeutic level during a typical 30-day treatment: and if so, does the presence of fish or the elimination of all living biological material impact the degradation of PZQ? Three 650 L marine aquarium systems, each containing 12 fish (French grunts: Haemulon flavolineatum), and three 650 L marine aquariums each containing no fish were treated with PZQ (2 ppm) and concentrations were measured daily for 30 days. After one round of treatment, the PZQ was no longer detectable in any system after 8 (±1) days. The subsequent two PZQ treatments yielded even faster PZQ breakdown (non-detectable after 2 days and 2 ± 1 day, respectively) with slight variations between systems. Linear mixed effects models of the data indicate that day and trial most impact PZQ degradation, while the presence of fish was not a factor in the best-fit models. In a completely sterilized marine system (0.5 L) PZQ concentration remained unchanged over 15 days, suggesting that PZQ may be stable in a marine system during this time period. The degradation observed in non-sterile marine systems in this study may be microbial in nature. This work should be taken into consideration when providing PZQ bath treatments to marine animals to ensure

  12. Praziquantel degradation in marine aquarium water.

    PubMed

    Thomas, Amber; Dawson, Matthew R; Ellis, Helen; Stamper, M Andrew

    2016-01-01

    Praziquantel (PZQ) is a drug commonly utilized to treat both human schistosomiasis and some parasitic infections and infestations in animals. In the aquarium industry, PZQ can be administered in a "bath" to treat the presence of ectoparasites on both the gills and skin of fish and elasmobranchs. In order to fully treat an infestation, the bath treatment has to maintain therapeutic levels of PZQ over a period of days or weeks. It has long been assumed that, once administered, PZQ is stable in a marine environment throughout the treatment interval and must be mechanically removed, but no controlled experiments have been conducted to validate that claim. This study aimed to determine if PZQ would break down naturally within a marine aquarium below its 2 ppm therapeutic level during a typical 30-day treatment: and if so, does the presence of fish or the elimination of all living biological material impact the degradation of PZQ? Three 650 L marine aquarium systems, each containing 12 fish (French grunts: Haemulon flavolineatum), and three 650 L marine aquariums each containing no fish were treated with PZQ (2 ppm) and concentrations were measured daily for 30 days. After one round of treatment, the PZQ was no longer detectable in any system after 8 (±1) days. The subsequent two PZQ treatments yielded even faster PZQ breakdown (non-detectable after 2 days and 2 ± 1 day, respectively) with slight variations between systems. Linear mixed effects models of the data indicate that day and trial most impact PZQ degradation, while the presence of fish was not a factor in the best-fit models. In a completely sterilized marine system (0.5 L) PZQ concentration remained unchanged over 15 days, suggesting that PZQ may be stable in a marine system during this time period. The degradation observed in non-sterile marine systems in this study may be microbial in nature. This work should be taken into consideration when providing PZQ bath treatments to marine animals to ensure maximum

  13. Uma comparação entre técnicas de propagação de erros em astrofísica: Monte Carlo x Bootstrap

    NASA Astrophysics Data System (ADS)

    Waelkens, A. H.; Janot Pacheco, E.

    2003-08-01

    Recentemente Dhillon & Watson (2001) criticaram o procedimento de determinação de erros via simulações de Monte Carlo no caso do imageamento indireto de estrelas, por introduzir ruído nos dados e resultar em erros superestimados. Estes autores propuseram a utilização alternativa do método de Bootstrap como uma técnica superior para a estimativa de erros. Neste trabalho apresentamos os resultados de um estudo comparativo da performance das técnicas de simulação por Monte Carlo e por Bootstrap para a determinação de erros em duas situações de interesse: (i) ajuste de modelos a espectros observados e (ii) imageamento indireto de discos de acréscimo com técnicas de mapeamento por eclipse. No caso (i), os dados de entrada são espectros de emissão simples de hidrogênio aos quais é adicionado ruído gaussiano de amplitude selecionada. No caso (ii), são produzidas curvas de luz do eclipse de uma distribuição de brilho seguindo a lei TµR-3/4 para discos estacionários cuja taxa de acréscimo varia ao longo do eclipse segundo uma distribuição gaussiana de amplitude selecionada, simulando o ruído. A avaliação da performance é feita com o auxílio de um diagrama do erro relativo na grandeza ajustada, conforme obtido por cada método, versus o erro relativo (ruído/sinal) dos dados de entrada. O estudo mostra que as duas técnicas produzem resultados semelhantes nos dois casos, e que a suposta superioridade do método de Bootstrap não se confirma.

  14. Praziquantel failure in the treatment of Fasciola hepatica

    PubMed Central

    Patrick, David Michael; Isaac-Renton, Judith

    1992-01-01

    A case of human fascioliasis is presented in which the patient remained symptomatic after treatment with praziquantel and other agents but eventually responded to bithionol. The difficulties in finding an efficacious and tolerable drug therapy for this condition are reviewed with reference to the life cycle and pathogenesis of the parasite. It is concluded that while bithionol remains the current drug of choice, triclabendazole may play a dominant role in the near future. PMID:22451761

  15. 21 CFR 520.1447 - Milbemycin oxime, lufenuron, and praziquantel tablets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Milbemycin oxime, lufenuron, and praziquantel tablets. 520.1447 Section 520.1447 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1447 Milbemycin oxime, lufenuron, and praziquantel tablets. (a) Specifications. Each...

  16. 21 CFR 520.1447 - Milbemycin oxime, lufenuron, and praziquantel tablets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Milbemycin oxime, lufenuron, and praziquantel tablets. 520.1447 Section 520.1447 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1447 Milbemycin oxime, lufenuron, and praziquantel tablets. (a) Specifications. Each...

  17. 21 CFR 520.1447 - Milbemycin oxime, lufenuron, and praziquantel tablets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Milbemycin oxime, lufenuron, and praziquantel tablets. 520.1447 Section 520.1447 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1447 Milbemycin oxime, lufenuron, and praziquantel tablets. (a) Specifications. Each...

  18. THE ACUTE TOXICITY OF PRAZIQUANTEL TO GRASS CARP AND GOLDEN SHINERS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Acute praziquantel toxicity and no observable effect concentrations (NOEC), were determined in the laboratory for grass carp and golden shiners, two commercially raised cyprinids known to harbor Asian tapeworm Bothriocephalus acheilognathi. Praziquantel is an anthelmintic used to treat fish with ta...

  19. Queda dos homicídios em São Paulo, Brasil: uma análise descritiva

    PubMed Central

    Peres, Maria Fernanda Tourinho; Vicentin, Diego; Nery, Marcelo Batista; de Lima, Renato Sérgio; de Souza, Edinilsa Ramos; Cerda, Magdalena; Cardia, Nancy; Adorno, e Sérgio

    2012-01-01

    Objetivo Descrever a evolução da mortalidade por homicídios no Município de São Paulo segundo tipo de arma, sexo, raça ou cor, idade e áreas de exclusão/inclusão social entre 1996 e 2008. Métodos Estudo ecológico de série temporal. Os dados sobre óbitos ocorridos no Município foram coletados da base de dados do Programa de Aprimoramento das Informações sobre Mortalidade, seguindo a Classificação Internacional de Doenças, Décima Revisão (CID-10). Foram calculadas as taxas de mortalidade por homicídio (TMH) para a população total, por sexo, raça ou cor, faixa etária, tipo de arma e área de exclusão/inclusão social. As TMH foram padronizadas por idade pelo método direto. Foram calculados os percentuais de variação no período estudado. Para as áreas de exclusão/inclusão social foram calculados os riscos relativos de morte por homicídio. Resultados As TMH apresentaram queda de 73,7% entre 2001 e 2008. Foi observada redução da TMH em todos os grupos analisados, mais pronunciada em homens (−74,5%), jovens de 15 a 24 anos (−78,0%) e moradores de áreas de exclusão social extrema (−79,3%). A redução ocorreu, sobretudo, nos homicídios cometidos com armas de fogo (−74,1%). O risco relativo de morte por homicídio nas áreas de exclusão extrema (tendo como referência áreas com algum grau de exclusão social) foi de 2,77 em 1996, 3,9 em 2001 e 2,13 em 2008. Nas áreas de alta exclusão social, o risco relativo foi de 2,07 em 1996 e 1,96 em 2008. Conclusões Para compreender a redução dos homicídios no Município, é importante considerar macrodeterminantes que atingem todo o Município e todos os subgrupos populacionais e microdeterminantes que atuam localmente, influenciando de forma diferenciada os homicídios com armas de fogo e os homicídios na população jovem, no sexo masculino e em residentes em áreas de alta exclusão social. PMID:21390415

  20. Uso de modelos mecânicos em curso informal de astronomia para deficientes visuais. Resgate de uma experiência

    NASA Astrophysics Data System (ADS)

    Tavares, E. T., Jr.; Klafke, J. C.

    2003-08-01

    O presente trabalho propõe-se a resgatar uma experiência que teve lugar no Planetário de São Paulo nos anos 60. Em 1962, o Sr. Acácio, então com 37 anos, deficiente visual desde os 27, passou a assistir às aulas ministradas pelo Prof. Aristóteles Orsini aos integrantes do corpo de servidores do Planetário. O Sr. Acácio era o único deficiente da turma e, embora possuísse conhecimentos básicos e relativamente avançados de matemática, enfrentava dificuldades na compreensão e acompanhamento da exposição, como também em estudos posteriores. Com o intuito de auxiliá-lo na superação desses problemas, o Prof. Orsini solicitou a construção de modelos mecânicos que, através do sentido do tato, permitissem o acompanhamento das aulas e a transposição do modelo para o "constructo" mental. Essa prática mostrou-se tão eficaz que facilitou sobejamente o aprendizado da matéria pelo sujeito. O Sr. Acácio passou a integrar o corpo de professores do Planetário/Escola Municipal de Astrofísica, tendo ficado responsável pelo curso de "Introdução à Astronomia" por vários anos. Além disso, a experiência foi tão bem sucedida que alguns dos modelos tiveram seus elementos constitutivos pintados diferencialmente para serem utilizados em cursos regulares do Planetário, tornando-se parte integrante do conjunto de recursos didáticos da instituição. É pensando nessa eficácia, tanto em seu objetivo original permitir o aprendizado de um deficiente visual quanto no subsidiário recurso didático sistemático da instituição que decidimos resgatar essa experiência. Estribados nela, acreditamos ser extremamente produtivo, em termos educacionais, o aperfeiçoamento dos modelos originais, agora resgatados e restaurados, e a criação de outros que pudessem ser utilizados no ensino dessa ciência a deficientes visuais.

  1. Human fascioliasis in Cajamarca/Peru. I. Diagnostic methods and treatment with praziquantel.

    PubMed

    Knobloch, J; Delgado, E; Alvarez, A; Reymann, U; Bialek, R

    1985-06-01

    In a prospective study 34 Peruvian fascioliasis patients were followed up for three months after treatment with praziquantel. The rapid sedimentation of faeces was demonstrated to be the most appropriate parasitological technique for the diagnosis of Fasciola hepatica infections in man compared to the MIF concentration or the examination of duodenal fluid by Enterotest. After therapy with different doses of praziquantel only 21% of the patients stopped to excrete worm eggs although 17 patients had been treated repeatedly. During the period of observation all patients presented a decreasing number of symptoms. It is concluded that praziquantel is not very active against F. hepatica in man. PMID:4023557

  2. Depletion of praziquantel in plasma and muscle tissue of cultured rockfish Sebastes schlegeli after oral and bath treatment.

    PubMed

    Kim, K H; Kim, C S; Kim, J W

    2001-08-01

    Depletion of praziquantel in plasma and muscle tissue after oral and bath treatments was studied in cultured rockfish Sebastes schlegeli. In the oral treatment, a single dose of 400 mg praziquantel kg(-1) body weight was administered by intubation of the stomach. A bath treatment at 100 ppm of praziquantel for 4 min was also carried out. Plasma and muscle tissue samples were collected at 3, 6, 12, 24, 48, 72, 96, 120, 144 and 168 h post-treatment, and analyzed for praziquantel by reversed-phase HPLC using diazepam as the internal standard. Following oral treatment, praziquantel was detected in plasma and muscle tissue until 96 h after treatment. In plasma the praziquantel concentration was highest at the 9 h sampling time and declined sharply at the 48 h sampling point. The concentrations of praziquantel in the muscle tissue were lower than those in the plasma, and the highest value was found at the 9 h sampling time. Following bath treatment, praziquantel was found in plasma and muscle tissue until 72 and 24 h after treatment, respectively. In plasma the praziquantel concentration was highest at the 12 h sampling time and declined sharply thereafter. The concentrations of praziquantel in the muscle tissue were significantly lower than those in the plasma, and the concentrations declined consistently with time. PMID:11558729

  3. 75 FR 54018 - Oral Dosage Form New Animal Drugs; Praziquantel and Pyrantel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... sizes of praziquantel and pyrantel pamoate tablets used in cats and kittens for the removal of various... pyrantel pamoate) Tablets used in cats and kittens for the removal of various internal parasites....

  4. Selective indications for the use of praziquantel in the treatment of brain cysticercosis.

    PubMed Central

    Vasconcelos, D; Cruz-Segura, H; Mateos-Gomez, H; Zenteno Alanis, G

    1987-01-01

    The selective use of praziquantel for the treatment of brain cysticercosis in human beings is described, based upon the results of clinical tests conducted during a 2 year period. Forty patients with clinical diagnosis of cysticercosis, confirmed and documented by CT, were treated. They are divided into four groups, representative of the various forms of the disease. The results assessed by clinical evaluation and sequential CT, give a ten point criterion of the indications for praziquantel. Images PMID:3495636

  5. Efficacy of 6-, 12-, and 24-h praziquantel bath treatments against Asian tapeworm Bothriocephalus acheilognathi in grass carp

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Praziquantel is an effective antihelmintic that has been used in dogs and cats as a de-wormer. It has also been used successfully against tapeworms and trematodes in fish. The current study tested the efficacy of praziquantel bath treatments at various concentrations (0.187, 0.375, 0.75, 1.5, 3.0,...

  6. Learning Astronomy by Playing in a Park. (Spanish Title: Aprender AstronoMía Jugando en Una Plaza.) Aprender Astronomia Brincando em Uma Praça

    NASA Astrophysics Data System (ADS)

    Camino, Néstor

    2012-12-01

    trabalho alguns jogos de praça, considerados como módulos didáticos para imaginar processos astronômicos, a partir da concepção de que a aprendizagem em Astronomia deve-se desenvolver fortalecendo a relação do próprio corpo com o espaço tridimensional e com o tempo, tal como se vive ao observar o céu, construindo um "diálogo" entre o mundo real e as aprendizagens a construir. Os jogos apresentados (carrosséis e tobogãs) foram desenhados para trabalhar sobre a translação da Terra em torno do Sol, as fases da Lua e a gravidade, e sobre o que um observador percebe dos mesmos. Dá-se a descrição de cada jogo, discutem-se seus fundamentos físicos e astronômicos, e desenvolve-se uma crítica didática dos mesmos. Finalmente, comenta-se o papel que deveriam ter os docentes no apoio aos aprendizes no processo de interação com os jogos apresentados.

  7. Solubility properties of racemic praziquantel and its enantiomers.

    PubMed

    el-Arini, S K; Giron, D; Leuenberger, H

    1998-11-01

    The purpose of this study was to characterize the solubility and thermodynamic properties of the optical isomers of the anti-schistosomal drug, praziquantel (PZQ) and to compare these properties to those of the racemic product used in commercial preparations (Biltricide, generic drugs). The crystalline enantiomers of PZQ exhibited different thermal properties than the racemic drug. The melting points and the enthalpies of fusion obtained from the differential scanning calorimetry (DSC) scans were nearly identical between the isomers and were substantially lower than those of racemic PZQ [(+/-)-PZQ]. The DSC results indicate that (+/-)-PZQ is a racemic compound and not a racemic mixture. This was confirmed by powder x-ray diffraction analysis and the IR spectra. The 30 degrees decrease in the melting point was reflected in increased solubility of the enantiomers, which amounted to twice that of the racemic PZQ. The behavior of the isomers in the presence of beta-cyclodextrin (beta-CD) was studied in water at 37 degrees C. The solubility data (phase solubility diagrams) were linear for up to the highest concentration of added beta-CD investigated. The apparent stability constants determined from the phase solubility diagrams showed that both the (+) and (-) enantiomers as well as (+/-)-PZQ exhibited moderate affinity to form a 1:1 complex in solution with beta-CD. The findings of this study may be of importance when efforts are considered to improve pharmaceutical formulation of this anti-schistosomal drug. PMID:9834959

  8. Pathways involved in trifluoperazine-, dibucaine- and praziquantel-induced hemolysis.

    PubMed

    Malheiros, S V; Meirelles, N C; de Paula, E

    2000-01-17

    This work elucidates differences in the hemolytic pathway developed by the antipsychotic trifluoperazine (TFP), the local anesthetic dibucaine (DBC) and the antihelminthic praziquantel (PZQ). Their partition coefficients (P) were measured at pH 7.4 between n-octanol, microsomes, liposomes, erythrocyte ghosts and n-octanol/water. The effective drug:lipid molar ratios for the onset of membrane solubilization (ReSAT) and complete hemolysis (ReSOL) were calculated from the experimental P values and compared with a classical surface-active compound treatment Lichtenberg, D. Biochim. Biophys. Acta 821 (1985) 470-478[. The contribution of charged/uncharged forms of TFP and DBC for the hemolytic activity was also analyzed. In all cases the hemolytic phenomena could be related to the monomeric drug insertion into the membrane. Only for TFP at isosmotic condition lysis occurs at concentrations beyond the CMC of the drug, indicating that micellization facilitates TFP hemolytic effect, while DBC and PZQ reach a real membrane saturation at their monomeric form. PMID:10672415

  9. THE SUSCEPTIBILITY OF RECENT ISOLATES OF Schistosoma mansoni TO PRAZIQUANTEL

    PubMed Central

    MENDONÇA, Adriana Maria B.; FEITOSA, Ana Paula S.; VERAS, Dyana L.; MATOS-ROCHA, Thiago J.; CAVALCANTI, Marília G. dos Santos; BARBOSA, Constança Clara G. S.; BRAYNER, Fábio A.; ALVES, Luiz C.

    2016-01-01

    Introduction: Schistosomiasis is a chronic disease caused by trematode flatworms of the genus Schistosoma and its control is dependent on a single drug, praziquantel (PZQ), but concerns over PZQ resistance have renewed interest in evaluating the in vitro susceptibility of recent isolates of Schistosoma mansoni to PZQ in comparison with well-established strains in the laboratory. Material and methods: The in vitro activity of PZQ (6.5-0.003 µg/mL) was evaluated in terms of mortality, reduced motor activity and ultrastructural alterations against S. mansoni. Results: After 3 h of incubation, PZQ, at 6.5 µg/mL, caused 100% mortality of all adult worms in the three types of recent isolates, while PZQ was inactive at concentrations of 0.08-0.003 µg/mL after 3 h of incubation. The results show that the SLM and Sotave isolates basically presented the same pattern of susceptibility, differing only in the concentration of 6.5 µg/mL, where deaths occurred from the range of 1.5 h in Sotave and just in the 3 h range of SLM. Additionally, this article presents ultrastructural evidence of rapid severe PZQ-induced surface membrane damage in S. mansoni after treatment with the drug, such as disintegration, sloughing, and erosion of the surface. Conclusion: According to these results, PZQ is very effective to induce tegument destruction of recent isolates of S. mansoni. PMID:26910445

  10. Praziquantel: physiological evidence for its site(s) of action in magnesium-paralysed Schistosoma mansoni.

    PubMed

    Blair, K L; Bennett, J L; Pax, R A

    1992-02-01

    The mechanism whereby praziquantel produces a contraction and subsequent flaccid paralysis (a loss of sensitivity to subsequent stimuli) of Schistosoma mansoni in a medium containing an elevated Mg2+:Ca2+ ratio was investigated. In RPMI, praziquantel produced a concentration-dependent tonic contraction of the parasite with an EC50 of 200 nM. Magnesium inhibited the contraction in such a manner as to convert the tonic contraction to a phasic one without altering the peak force generated. The Mg(2+)-dependent block was non-competitive with praziquantel but was competitive with extracellular Ca2+, ratios of 7.5:1;Mg2+:Ca2+ being needed to inhibit the tonic contraction and to induce flaccid paralysis. Flaccid paralysis was associated with a reduced ability of the parasite to take up 45Ca2+ from the bath compared to parasites that had not entered into flaccid paralysis and flaccid paralysis was reversible. Recovery from flaccid paralysis was accelerated by treatments that are expected to increase Ca2+ uptake by the parasite. At a concentration of 500 nM, praziquantel produced 2 distinct phasic contractions in intact parasites incubated in an elevated [Mg2+] medium but only 1 phasic contraction in parasites lacking their surface tegumental membranes. In zero Ca2+ I-RPMI, 10 microM praziquantel produced a phasic contraction of intact parasites but did not stimulate contraction of detegumented parasites until Ca2+ was reintroduced into the bath. These results indicate that praziquantel interacts with specific Ca(2+)-permeable sites in the tegumental and sarcoplasmic membranes of the parasite and that under these conditions of elevated Mg2+:Ca2+ ratios, these sites become blocked by Mg2+, leading to flaccid paralysis of the parasite. PMID:1614741

  11. Activity of Praziquantel Enantiomers and Main Metabolites against Schistosoma mansoni

    PubMed Central

    Meister, Isabel; Ingram-Sieber, Katrin; Cowan, Noemi; Todd, Matthew; Robertson, Murray N.; Meli, Claudia; Patra, Malay; Gasser, Gilles

    2014-01-01

    A racemic mixture of R and S enantiomers of praziquantel (PZQ) is currently the treatment of choice for schistosomiasis. Though the S enantiomer and the metabolites are presumed to contribute only a little to the activity of the drug, in-depth side-by-side studies are lacking. The aim of this study was to investigate the in vitro activities of PZQ and its main metabolites, namely, R- and S-cis- and R- and S-trans-4′-hydroxypraziquantel, against adult worms and newly transformed schistosomula (NTS). Additionally, we explored the in vivo activity and hepatic shift (i.e., the migration of the worms to the liver) produced by each PZQ enantiomer in mice. Fifty percent inhibitory concentrations of R-PZQ, S-PZQ, and R-trans- and R-cis-4′-hydroxypraziquantel of 0.02, 5.85, 4.08, and 2.42 μg/ml, respectively, for adult S. mansoni were determined in vitro. S-trans- and S-cis-4′-hydroxypraziquantel were not active at 100 μg/ml. These results are consistent with microcalorimetry data and studies with NTS. In vivo, single 400-mg/kg oral doses of R-PZQ and S-PZQ achieved worm burden reductions of 100 and 19%, respectively. Moreover, worms treated in vivo with S-PZQ displayed an only transient hepatic shift and returned to the mesenteric veins within 24 h. Our data confirm that R-PZQ is the main effector molecule, while S-PZQ and the metabolites do not play a significant role in the antischistosomal properties of PZQ. PMID:24982093

  12. Reduction in hookworm infection after praziquantel treatment among children and young adults in Leyte, the Philippines.

    PubMed

    Shaw, Julia G; Aggarwal, Nitin; Acosta, Luz P; Jiz, Mario A; Wu, Hai-Wei; Leenstra, Tjalling; Coutinho, Hannah M; Olveda, Remigio M; Kurtis, Jonathan D; McGarvey, Stephen T; Friedman, Jennifer F

    2010-08-01

    One small previous study found that praziquantel reduced hookworm infection. In this study, 607 subjects were enrolled in a longitudinal study. At enrollment and every 3 months for 18 months, three stool samples were collected, and the intensity of infection with Schistosoma japonicum and soil-transmitted helminths (STHs) was quantified. All subjects were treated with 60 mg/kg praziquantel at baseline. Three months post-treatment, the percent of subjects who were hookworm-infected decreased to 46.5% from 61% at baseline. The putative cure rate was 23.7%. The 95% confidence interval around the change in hookworm egg counts from baseline to 6 and 12 months post-treatment was negative and did not include zero. The percent reduction in hookworm egg counts from baseline to 3 months post-treatment was 40.8%. Praziquantel treatment did not decrease the infection intensity of STHs. Control programs using praziquantel may have the added benefit of reducing hookworm infection and anemia in areas of coendemnicity. PMID:20682892

  13. Combination of Praziquantel and Aspirin Minimizes Liver Pathology of Hamster Opisthorchis viverrini Infection Associated Cholangiocarcinoma.

    PubMed

    Sudsarn, Pakkayanee; Boonmars, Thidarut; Ruangjirachuporn, Wipaporn; Namwat, Nisana; Loilome, Watcharin; Sriraj, Pranee; Aukkanimart, Ratchadawan; Nadchanan, Wonkchalee; Jiraporn, Songsri

    2016-01-01

    Opisthorchiasis is one of the major risk factors for cholangiocarcinoma (CCA) in northeastern Thailand. An effective drug for killing this parasite is praziquantel. Recently, several reports have shown that with frequent use, praziquantel may itself be a CCA risk and can cause liver cell damage from an immunopathological response after parasite death. Aspirin has many properties including anti-inflammation and anti-cancer. Therefore, we use of aspirin (As) and praziquantel (Pz) to improve hepatobiliary system function in hamsters infected with Opisthorchis viverrini (OV) and or administered N-nitrosodimethylamine (ND). Livers of OVNDAsPz, appeared healthy macroscopically, suggesting slow progression of cholangiocarcinoma evident by extent of fibrosis and bile duct cell proliferation was less than OVND although aggregations of inflammatory cells remained. Proliferating cell nuclear antigen (PCNA), cytokeratin 19 (CK19), and cancer antigen (CA19-9) staining were strongly positive in OVND, but were only slight in OVNDAs. Moreover, OVNDAsPz, appeared a few inflammatory infiltrations, bile duct proliferation, fibrosis and CCA area than the OVNDAs group. Thirty seven point five percent of hamster in this group could not develop CCA. These findings suggest that using aspirin combination with praziquantel treatment can improve the hepatobiliary system after O. viverrini infection and reduce the risk of CCA. PMID:26277607

  14. New Insight into the Antifibrotic Effects of Praziquantel on Mice in Infection with Schistosoma japonicum

    PubMed Central

    Liang, Yue-Jin; Luo, Jie; Yuan, Quan; Zheng, Dan; Liu, Ya-Ping; Shi, Lei; Zhou, Ying; Chen, Ai-Ling; Ren, Yong-Ya; Sun, Ke-Yi; Sun, Yan; Wang, Yong; Zhang, Zhao-Song

    2011-01-01

    Background Schistosomiasis is a parasitic disease infecting more than 200 million people in the world. Although chemotherapy targeting on killing schistosomes is one of the main strategies in the disease control, there are few effective ways of dealing with liver fibrosis caused by the parasite infection in the chronic and advanced stages of schistosomiasis. For this reason, new strategies and prospective drugs, which exert antifibrotic effects, are urgently required. Methods and Findings The antifibrotic effects of praziquantel were assessed in the murine models of schistosomiasis japonica. Murine fibrosis models were established by cutaneous infection with 14±2 Schistosoma japonicum cercariae. Then, the mice of both chronic (8 weeks post-infection) and advanced (15 weeks post-infection) schistosomiasis were treated by gavage of praziquantel (250 mg/kg, once daily for 3 days) to eliminate worms, and followed by praziquantel anti-fibrosis treatment (300 mg/kg, twice daily for 30 days). The fibrosis-related parameters assessed were areas of collagen deposition, content of hydroxyproline and mRNA expressions of Col1α1, Col3α1, α-SMA, TGF-β, MMP9, TIMP1, IL-4, IL-10, IL-13 and IFN-γ of liver. Spleen weight index, alanine aminotransferase activity and liver portal venous pressure were also measured. The results showed that anti-fibrosis treatment improved liver fibrosis, splenomegaly, hepatic function, as well as liver portal hypertension. In order to confirm the anti-fibrotic properties of praziquantel, we established a CCL4-induced model and revealed that CCL4-induced liver fibrosis was inhibited by PZQ treatment for 30 days. Furthermore, we analyzed the effects of praziquantel on mouse primary hepatic stellate cells (HSCs). It is indicated that mRNA expressions of Col1α1, Col3α1, α-SMA, TGF-β, MMP9 and TIMP1 of HSCs were all inhibited after praziquantel anti-parasite treatments. Conclusions The significant amelioration of hepatic fibrosis by praziquantel

  15. Efficacy of oxamniquine and praziquantel in the treatment of Schistosoma mansoni infection: a controlled trial.

    PubMed Central

    Ferrari, M. L. A.; Coelho, P. M. Z.; Antunes, C. M. F.; Tavares, C. A. P.; da Cunha, A. S.

    2003-01-01

    OBJECTIVE: To evaluate the therapeutic efficacy of oxamniquine and praziquantel, the two most clinically important schistosomicide drugs, and to compare the accuracy of faecal examination with the accuracy of oogram in testing for Schistosoma mansoni infection. METHODS: In a triple-masked and randomized controlled trial, 106 patients infected with S. mansoni were randomly allocated to one of three statistically homogeneous groups. One group was given 60 mg/kg praziquantel per day for three consecutive days, another was given two daily doses of 10 mg/kg oxamniquine, and the placebo group received starch. Faecal examinations (days 15, 30, 60, 90, 120, 150, and 180 after treatment) and biopsy of rectal mucosa by quantitative oogram (days 30, 60, 120, and 180) were used for the initial diagnosis and for evaluating the degree of cure. The chi2 test and the Kruskal-Wallis test were used to compare variables in the three groups. Survival analysis (Kaplan-Meier) and the log-rank test were used to evaluate the efficacy of the treatments. FINDINGS: The sensitivity of stool examinations ranged from 88.9% to 94.4% when patients presented with >5000 S. mansoni eggs per gram of tissue (oogram); when the number of eggs dropped to <1000 eggs per gram, sensitivity was reduced (range, 22.7-34.0%). When cure was evaluated by stool examination, oxamniquine and praziquantel had cure rates of 90.3% and 100%, respectively. However, when the oogram was used as an indicator of sensitivity, the oxamniquine cure rate dropped dramatically (to 42.4%), whereas the rate for praziquantel remained high, at 96.1%. CONCLUSIONS: Praziquantel was significantly more effective than oxamniquine in treating S. mansoni infection. The oogram was markedly more sensitive than stool examinations in detecting S. mansoni eggs and should be recommended for use in clinical trials with schistosomicides. PMID:12764515

  16. Safety of the Combined Use of Praziquantel and Albendazole in the Treatment of Human Hydatid Disease

    PubMed Central

    Alvela-Suárez, Lucía; Velasco-Tirado, Virginia; Belhassen-Garcia, Moncef; Novo-Veleiro, Ignacio; Pardo-Lledías, Javier; Romero-Alegría, Angela; Pérez del Villar, Luis; Valverde-Merino, María Paz; Cordero-Sánchez, Miguel

    2014-01-01

    There is still no well-established consensus about the clinical management of hydatidosis. Currently, surgery continues to be the first therapeutic option, although treatment with anti-parasitic drugs is indicated as an adjuvant to surgery to decrease the number of relapses and hydatid cyst size. When surgery is not possible, medical treatment is indicated. Traditionally, albendazole was used in monotherapy as the standard treatment. However, combined therapy with albendazole plus praziquantel appears to improve anti-parasitic effectiveness. To date, no safety studies focusing on such combined therapy have been published for the treatment of hydatidosis. In this work, we analyze the adverse effects seen in 57 patients diagnosed with hydatidosis who were treated with praziquantel plus albendazole combined therapy between 2006 and 2010. PMID:24615131

  17. Aspects of decontamination of ivermectin and praziquantel from environmental waters using advanced oxidation technology.

    PubMed

    Havlíková, Lucie; Šatínský, Dalibor; Solich, Petr

    2016-02-01

    Recently performed environmental risk assessments of ivermectin demonstrated the need to complete the information regarding the fate of ivermectin in environment. There is also a lack of information concerning the fate and stability of praziquantel. The forced degradation study and photocatalytic degradation pathways in aqueous TiO2 suspensions of the two anthelmintics ivermectin and praziquantel were investigated and compared. The degradation efficiency increased for both compounds with the increase in the TiO2 concentration from 0.25 to 2.00 g L(-1), and then remained constant. The estimated k-values were from 0.36 h(-1) to 0.64 h(-1) for IVE and from 0.29 h(-1) to 0.47 h(-1) for PZQ, respectively. The degradation rate was not significantly impacted by the change of the pH value (pH 3, 5, 7, and 9) at 2.0 g L(-1) of TiO2. The photo degradation was about 90% for both compounds after 5 h of irradiation and it was significantly inhibited in the presence of iodide anion and isopropyl alcohol, which indicated, that hydroxyl radicals as well as holes contributed to the degradation of both anthelmintics. The contribution of hydroxyl radicals and holes was 92.1% for IVE and 93.2% for PZQ, respectively. Photocatalytic process of ivermectin resulted in three degradation intermediates; another two were formed during acidic and basic hydrolysis. Praziquantel underwent degradation to six degradation intermediates; four of them were formed under photocatalytic irradiation. The intermediates were identified using UHPLC-MS/MS. UV/TiO2 photolysis has been found as an effective advanced oxidation technology for the decontamination of ivermectin and praziquantel. PMID:26344145

  18. Acute visceral cysticercosis by Taenia hydatigena in lambs and treatment with praziquantel.

    PubMed

    Scala, A; Urrai, G; Varcasia, A; Nicolussi, P; Mulas, M; Goddi, L; Pipia, A P; Sanna, G; Genchi, M; Bandino, E

    2016-01-01

    An acute outbreak of Taenia hydatigena cysticercosis, causing mortality in 5 of 21 (23.8%) female lambs, is reported. Gross post-mortem examinations and histology showed Cysticercus tenuicollis as the cause of death. Biochemical parameters in infected lambs confirmed severe hepatitis. Praziquantel, given once at 15 mg/kg body weight (bw), was administered and a dramatic improvement in the clinical condition and biochemical parameters was observed up to 30 days following treatment. PMID:25120032

  19. Preliminary trials with praziquantel in human infections due to Schistosoma mansoni

    PubMed Central

    Katz, N.; Rocha, R.S.; Chaves, A.

    1979-01-01

    As part of a programme of multicentre trials of the tolerance and therapeutic effect of praziquantel, clinical trials were carried out in Brazil in patients with active Schistosoma mansoni infections, each of whom had a minimum geometric mean egg output of 100 eggs per gram of faeces calculated from multiple pretreatment stool examinations. The first stage was a double-blind assessment of tolerance and efficacy of oral doses of 1 × 20, 2 × 20, or 3 × 20 mg of praziquantel per kg of body weight. Subsequently, single-blind trials explored the effects of 3 × 20 mg/kg at 4-hourly intervals, and a single dose of 50 mg/kg. Side effects increased in frequency as dosage increased. Nausea, epigastric pain, headache, dizziness, and drowsiness were all noted but their severity was mild or moderate and they disappeared in 48 hours. In general, monitoring laboratory tests showed little change. Following a stringent parasitological follow-up, 96% of 28 patients followed at 1 year after treatment with either 3 × 20 mg/kg or 1 × 50 mg/kg were cured. Praziquantel seems to be a very promising drug against S. mansoni and further clinical trials should be strongly encouraged. PMID:396054

  20. Efficacy and Safety of Praziquantel, Tribendimidine and Mebendazole in Patients with Co-infection of Clonorchis sinensis and Other Helminths

    PubMed Central

    Xu, Li-Li; Jiang, Bin; Duan, Ji-Hui; Zhuang, Shi-Feng; Liu, Yong-Chun; Zhu, Shi-Qiao; Zhang, Li-Ping; Zhang, Hao-Bing; Xiao, Shu-Hua; Zhou, Xiao-Nong

    2014-01-01

    Background Both tribendimidine and mebendazole are broad-spectrum drugs for anti-intestinal nematodes. We aim to assess the efficacy and safety of tribendimidine and mebendazole in patients with co-infection of Clonorchis sinensis and other helminths. Method We performed a randomized open-label trial in Qiyang, People's Republic of China. Eligible participants were randomly assigned to one of four groups: (i) a single dose of 400 mg tribendimidine, (ii) 200 mg tribendimidine twice daily, (iii) 75 mg/kg praziquantel divided in four doses within 2 days, and (iv) a single dose of 400 mg mebendazole. Cure rates and egg reduction rates were assessed, and adverse events were monitored after treatments. Uncured patients accepted the second treatment with the same drugs after the first treatment. Results 156 patients were eligible for the study. Results from the first treatment showed that the cure rates of single-dose tribendimidine and praziquantel against C. sinensis were 50% and 56.8%, respectively; the single-dose tribendimidine achieved the cure rate of 77.8% in the treatment for hookworm, which was significantly higher than that of praziquantel; Low cure rates were obtained in the treatment of single-dose tribendimidine against Ascaris lumbricoides and Trichuris trichiura (28.6% and 23.1%). Results of the second treatment illustrated the cure rates of tribendimidine and praziquantel against C. sinensis were 78.1% and 75%, respectively. Most adverse events were mild and transient. Adverse events caused by tribendimidine were significantly less than praziquantel. Conclusion Single-dose tribendimidine showed similar efficacy against C. sinensis as praziquantel with less adverse events, and achieved significantly higher cure rate in the treatment for hookworm than those of praziquantel and mebendazole. Low cure rates, which were still higher than other drugs, were obtained in the treatment of single-dose tribendimidine against Ascaris lumbricoides and Trichuris

  1. Novel praziquantel treatment regime for controlling Asian tapeworm infections in pond-reared fish

    USGS Publications Warehouse

    Iles, Alison C.; Archdeacon, Thomas P.; Bonar, Scott A.

    2012-01-01

    The Asian tapeworm Bothriocephalus achelognathii is an intestinal fish parasite that is nonnative to but widespread throughout the southwestern United States. Praziquantel is an anthelminthic drug commonly used to treat fish for Asian tapeworm; however, it does not kill tapeworm eggs, so the water in ponds used for fish rearing must be exchanged after treatment. Our objective was to determine whether a system containing both an intermediate copepod host and a definitive fish host for Asian tapeworm could be treated without exchanging the water by using a follow-up treatment for any tapeworms that developed from eggs released before or during the first treatment. Here, we have described a new praziquantel treatment regimen to control Asian tapeworm infections in freshwater-reared fish. To evaluate the efficacy of this regimen, we stocked 50 red shiners Cyprinella lutrensis and an intermediate copepod host, Cyclops vernalis, into each of six pond mesocosms containing artificial macrophytes, sand, and gravel to simulate natural pools and provide suitable substrate for the copepod's life history. The test fish population had been naturally infected with B. achelognathii and had an initial infection prevalence of 14% and an infection intensity of 2.14 ± 2.19 (mean ± SD) worms per fish. Three mesocosms were treated twice, each with 2.5 mg/L praziquantel; 19 d passed between treatments to allow for possible reinfection to occur. After a 2.5-month posttreatment period to allow any remaining tapeworms to reestablish themselves, we killed and dissected all of the remaining fish. No worms were found in treated fish; however, the control group had an infection prevalence of 18 ± 6% and an infection intensity of 3.45 ± 2.1 worms per fish. Based on these results, we concluded that the praziquantel treatment regime administered was efficacious and suggest testing it on a larger scale. We caution that praziquantel has not been approved by the U.S. Food and Drug Administration

  2. The toxicity of praziquantel against Mesocestoides vogae (syn. corti) tetrathyridia can be assessed using a novel in vitro system.

    PubMed

    Saldaña, Jenny; Casaravilla, Cecilia; Marín, Mónica; Fernández, Cecilia; Domínguez, Laura

    2003-04-01

    We recently standardised Mesocestoides vogae (syn. corti) tetrathyridia cultures in the presence of sodium taurocholate. Parasite clustering and segmentation were observed as taurocholate-dependent effects in biphasic and monophasic media, respectively, and both were inhibited by a specific minimum inhibitory concentration (m.i.c.) of the cestocidal drugs albendazol and praziquantel. In the present study, we analysed the relationship between clustering inhibition and drug toxicity using praziquantel and a mouse experimental infection. In an "in vitro-in vivo" trial, a significant (ANOVA, P<0.05) reduction was observed in the infectivity of tetrathyridia previously cultured with praziquantel m.i.c. (0.06 micro g/ml) for 10 days. In an "in vivo-in vitro" trial, the clustering of tetrathyridia recovered from mice treated with praziquantel was found to be markedly reduced: 22%, compared with 83% cluster-containing wells of parasites from control mice. These results show that the outcome of infection and the suppression of taurocholate-induced clustering provide consistent indications of praziquantel toxicity against M. vogae, an observation confirmed by histological studies. The easily recorded clustering inhibition of M. vogae tetrathyridia in biphasic medium is a potentially useful system for the assessment of drug toxicity against cestode larvae. PMID:12658458

  3. Uma Comparação entre Técnicas de Propagação de Erros em Astrofísica: Monte Carlo x Bootstrap

    NASA Astrophysics Data System (ADS)

    Zabot, Alexandre; Baptista, Raymundo

    2005-07-01

    Neste trabalho é feito um estudo comparativo entre dois algoritmos numéricos usados para propagação de erros em dados experimentais. Um deles é conhecido por Método de Monte carlo e o outro por Método de Bootstrap. Recentemente, Dhullon & Watson argüiram que a aplicação do método de Monte Carlo introduz ruído nos dados, e propuseram então a utilização do Bootstrap como alternativa capaz de produzir resultados superiores. O objetivo deste trabalho é testar a validade dessa afirmação. As duas técnicas foram aplicadas a três problemas diferentes: o ajsute de modelos de emissão LTE simples e atmosfera estelar a espectros estelares observados e o ajuste de curvas de luz de eclipses de Variáveis Cataclísmicas para a detemrinação da distribuição radial de brilho dos seus discos de acréscimo. Os métodos foram testados quanto à sua robusteza, ou seja, a capacidade de prover resultados coerentes enre si. Além disso, as soluções dos métodos foram comparadas. Os resultados indicam que não existe evidência de superioridade de um métodos em relação ao outro.

  4. Time course of the effect of praziquantel on Schistosoma mansoni attachment in vitro: comparison with its effects on worm length and motility.

    PubMed

    da Silva, S P; Noël, F

    1995-01-01

    We report herein that praziquantel inhibits the capacity of adult male Schistosoma mansoni to attach to the bottom of a glass dish and produces a diminution of worm length and motility, acting under a similar concentration and time dependency. After removal of 1 microM praziquantel from the medium, the worms progressively recuperated their initial length and motility without recovering their attachment capability. The absence of calcium or presence of 1 microM verapamil did not change the praziquantel-induced effect on worm attachment, causing only a transient decrease in worm length and motility. The present data indicate that the diminution of motility induced by praziquantel results from the progressive contraction of the longitudinal musculature of the worm. In contrast, the loss of attachment should not be causally related to the contraction of the worm since these two praziquantel-induced effects have distinct patterns of response under some experimental conditions. PMID:7479644

  5. Bimodal X-ray and Infrared Imaging of an Organometallic Derivative of Praziquantel in Schistosoma mansoni.

    PubMed

    Clède, Sylvain; Cowan, Noemi; Lambert, François; Bertrand, Hélène C; Rubbiani, Riccardo; Patra, Malay; Hess, Jeannine; Sandt, Christophe; Trcera, Nicolas; Gasser, Gilles; Keiser, Jennifer; Policar, Clotilde

    2016-06-01

    An organometallic derivative of praziquantel was studied directly in worms by using inductively coupled plasma-mass spectrometry (ICP-MS) for quantification and synchrotron-based imaging. X-ray fluorescence (XRF) and IR absorption spectromicroscopy were used for the first time in combination to directly locate this organometallic drug candidate in schistosomes. The detection of both CO (IR) and Cr (XRF) signatures proved that the Cr(CO)3 core remained intact in the worms. Images showed a preferential accumulation at the worm's tegument, consistent with a possible targeting of the calcium channel but not excluding other biological targets inside the worm. PMID:26991635

  6. Praziquantel induced oxidative stress and apoptosis-like cell death in Raillietina echinobothrida.

    PubMed

    Giri, Bikash Ranjan; Roy, Bishnupada

    2016-07-01

    Praziquantel (PZQ) is an anthelmintic drug used against trematode and cestode parasites of humans and veterinary animals. Since praziquantel was introduced as a broadspectrum anthelmintic, numerous studies described its successful use against helminth parasites, but its exact mechanism of action is feebly understood. Therefore, the present study was carried out to evaluate the possible role of PZQ induced oxidative stress in apoptosis-like cell death in the poultry tapeworm Raillietina echinobothrida. Parasite viability assay revealed a time-dependent reduction in the worm viability compared to the control. Transmission electron microscopy showed typical apoptotic features like condensed nucleus, damaged nuclear envelope and altered mitochondrial membrane in PZQ exposed parasites. Results revealed chromatin condensation and DNA fragmentation in PZQ exposed parasites. There was a notable decline in the level of glutathione and glutathione-s-transferase activity leading to the augmented generation of reactive oxygen species. This led to the alterations in the mitochondrial membrane potential with increased active caspase-3/7, confirms the involvement of mitochondria in the event. The present study suggests that PZQ exerts oxidative stress leading to apoptosis-like events in the parasites resulting their death. PMID:27005397

  7. Cytokine Pattern of T Lymphocytes in Acute Schistosomiasis mansoni Patients following Treated Praziquantel Therapy.

    PubMed

    Silveira-Lemos, Denise; Fernandes Costa-Silva, Matheus; Cardoso de Oliveira Silveira, Amanda; Azevedo Batista, Mauricio; Alves Oliveira-Fraga, Lúcia; Soares Silveira, Alda Maria; Barbosa Alvarez, Maria Carolina; Martins-Filho, Olindo Assis; Gazzinelli, Giovanni; Corrêa-Oliveira, Rodrigo; Teixeira-Carvalho, Andréa

    2013-01-01

    Acute schistosomiasis is associated with a primary exposure and is more commonly seen in nonimmune individuals traveling through endemic regions. In this study, we have focused on the cytokine profile of T lymphocytes evaluated in circulating leukocytes of acute Schistosomiasis mansoni-infected patients (ACT group) before and after praziquantel treatment (ACT-TR group). Our data demonstrated increased values of total leukocytes, eosinophils, and monocytes in both groups. Interestingly, we have observed that patients treated with praziquantel showed increased values of lymphocytes as compared with noninfected group (NI) or ACT groups. Furthermore, a decrease of neutrophils in ACT-TR was observed when compared to ACT group. Analyses of short-term in vitro whole blood stimulation demonstrated that, regardless of the presence of soluble Schistosoma mansoni eggs antigen (SEA), increased synthesis of IFN-γ and IL-4 by T-cells was observed in the ACT group. Analyses of cytokine profile in CD8 T cells demonstrated higher percentage of IFN-γ and IL-4 cells in both ACT and ACT-TR groups apart from increased percentage of IL-10 cells only in the ACT group. This study is the first one to point out the relevance of CD8 T lymphocytes in the immune response induced during the acute phase of schistosomiasis. PMID:23401741

  8. Cytokine Pattern of T Lymphocytes in Acute Schistosomiasis mansoni Patients following Treated Praziquantel Therapy

    PubMed Central

    Silveira-Lemos, Denise; Fernandes Costa-Silva, Matheus; Cardoso de Oliveira Silveira, Amanda; Azevedo Batista, Mauricio; Alves Oliveira-Fraga, Lúcia; Soares Silveira, Alda Maria; Barbosa Alvarez, Maria Carolina; Martins-Filho, Olindo Assis; Gazzinelli, Giovanni; Corrêa-Oliveira, Rodrigo; Teixeira-Carvalho, Andréa

    2013-01-01

    Acute schistosomiasis is associated with a primary exposure and is more commonly seen in nonimmune individuals traveling through endemic regions. In this study, we have focused on the cytokine profile of T lymphocytes evaluated in circulating leukocytes of acute Schistosomiasis mansoni-infected patients (ACT group) before and after praziquantel treatment (ACT-TR group). Our data demonstrated increased values of total leukocytes, eosinophils, and monocytes in both groups. Interestingly, we have observed that patients treated with praziquantel showed increased values of lymphocytes as compared with noninfected group (NI) or ACT groups. Furthermore, a decrease of neutrophils in ACT-TR was observed when compared to ACT group. Analyses of short-term in vitro whole blood stimulation demonstrated that, regardless of the presence of soluble Schistosoma mansoni eggs antigen (SEA), increased synthesis of IFN-γ and IL-4 by T-cells was observed in the ACT group. Analyses of cytokine profile in CD8 T cells demonstrated higher percentage of IFN-γ and IL-4 cells in both ACT and ACT-TR groups apart from increased percentage of IL-10 cells only in the ACT group. This study is the first one to point out the relevance of CD8 T lymphocytes in the immune response induced during the acute phase of schistosomiasis. PMID:23401741

  9. Efficacy of emodepside plus praziquantel tablets (Profender tablets for dogs) against mature and immature adult Trichuris vulpis infections in dogs.

    PubMed

    Schimmel, Annette; Altreuther, Gertraut; Schroeder, Iris; Charles, Samuel; Cruthers, Larry; Kok, Dawid J; Kraemer, Friederike; Krieger, Klemens J

    2009-08-01

    This paper reports on the efficacy of a novel flavoured tablet formulation of emodepside plus praziquantel (Profender tablets for dogs) against mature and immature adult whipworms (Trichuris vulpis) at the proposed minimum dose of 1 mg emodepside and 5 mg praziquantel per kg body weight in dogs. Three randomised, blinded and controlled laboratory studies with naturally or experimentally infected dogs were performed. The first study was conducted as a dose determination study in experimentally infected dogs using three different dose levels, i.e., 0.5x, 1x and 2x the minimum therapeutic dose. Two further studies confirmed the efficacy of emodepside plus praziquantel tablets against mature and immature adult T. vulpis at the recommended minimum dose. In all three studies, the efficacy against mature and immature adult T. vulpis was >99%. No side effects of the treatment were observed. It is concluded that the emodepside plus praziquantel tablet is an effective and safe treatment against mature and immature adult stages of T. vulpis in dogs. PMID:19575221

  10. Elimination of Asian fish tapeworms from grass carp with praziquantel bath treatments: The need for 24 hour exposures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several states require that imported fish be free of the Asian fish tapeworm Bothriocephalus acheilognathi. Praziquantel has been used for several years to treat fish with Asian fish tapeworms but rates and exposure periods necessary to eliminate these tapeworms from infected fish have not been ade...

  11. Sex- and stage-related sensitivity of Schistosoma mansoni to in vivo and in vitro praziquantel treatment.

    PubMed

    Pica-Mattoccia, Livia; Cioli, Donato

    2004-03-29

    The efficacy of praziquantel against a Puerto Rican strain of Schistosoma mansoni was assessed using both in vivo and in vitro approach. The drug effective dose (50%) in the infected mouse model was about 30 times higher when determined against 28-day-old infections than against 7-week-old parasites. Single-sex female infections were also largely refractory to treatment and single-sex male infections moderately refractory, in comparison with bisexual infections. The in vitro approach consisted of overnight exposure of parasite cultures to various drug concentrations, followed by several days of culture in drug-free medium. In vitro results confirmed in vivo data and allowed for the observation of schistosome morphological phenomena after praziquantel exposure. Early worm contraction was observed in all cases, even after exposure to sub-lethal concentrations of praziquantel or upon exposure of the largely refractory 28-day-old schistosomes. In these instances, however, worms resumed movements and normal shape upon drug removal and were able to survive. The inference of these observations on the clinical use of praziquantel and on its mechanism of action is discussed. PMID:15013742

  12. Effect of artemether, artesunate, OZ78, praziquantel, and tribendimidine alone or in combination chemotherapy on the tegument of Clonorchis sinensis.

    PubMed

    Keiser, Jennifer; Vargas, Mireille

    2010-09-01

    We investigated the morphological effects of half-strength treatments with praziquantel, artemether, artesunate, OZ78 and tribendimidine as well as combinations of praziquantel with artemether, artesunate, OZ78 and tribendimidine and an artesunate-tribendimidine combination in rats harboring adult Clonorchis sinensis. Rats were infected with C. sinensis, dosed orally with single agents or combination treatments and flukes recovered at 3 or 5 days post-treatment. The number of flukes was counted, the viability recorded and surface changes monitored by scanning electron microscopy. Drug effects induced by the individual drugs at sub-curative doses 3 days post-treatment were minor with the exception of flukes recovered from rats treated with artemether and tribendimidine. Treatment with the praziquantel combinations of artesunate, OZ78 and tribendimidine did not produce a greater disruption of the tegument than the individual drugs 3 days post-treatment. On the other hand, at this time point many worms treated with artemether-praziquantel had died and eruptions, roughening or blebbing were observed on all worms examined. Five days post-treatment flukes exposed to any of the praziquantel combinations in rats had died. Rats treated with an artesunate-tribendimidine combination resulted in a rapid death of flukes, 3 days post-treatment all worms had been expelled. In conclusion, we have confirmed the promising clonorchicidal properties of different drug combinations in rats. Differences in the extent and time-scale of tegumental disruption have been observed. The effect of drug combinations against C. sinensis requires further scientific inquiry, e.g. in transmission electron microscopy studies and in the C. sinensis-rabbit model. PMID:20416396

  13. Efficacy of Milbemax (milbemycin oxime + praziquantel) in the treatment of dogs experimentally infected with Crenosoma vulpis.

    PubMed

    Conboy, G; Bourque, A; Miller, L; Seewald, W; Schenker, R

    2013-12-01

    Crenosoma vulpis, the fox lungworm, infects wild and domestic canids and is a cause of chronic respiratory disease in dogs in North America and Europe. The objective of this study was to determine the efficacy of milbemycin oxime (0.5mg/kg)/praziquantel (5mg/kg) (Milbemax; Novartis Animal Health, Inc.) against C. vulpis infection in a randomized, blinded, placebo-controlled study using experimentally infected dogs. Sixteen beagles (8 males, 8 females) were each given 100 infective third-stage larvae of C. vulpis. Fecal samples were examined for first-stage larvae by quantitative Baermann examination pre-exposure and at days 21, 28, 35, 42 and 49 post-infection (PI). All of the dogs were shedding larvae in the feces at 21 days PI. The dogs were randomly assigned to one of two groups. At 28 days PI, Group 1 (4 males, 4 females) received placebo only while Group 2 (4 males, 4 females) received a single treatment of milbemycin oxime (0.5mg/kg) and praziquantel (5mg/kg). The 16 dogs were euthanized and necropsied at 49 days PI. Lungs were removed, assessed for gross lesions (graded on a subjective scale 0-3 with 0 being normal) and C. vulpis were collected by lung-flush and counted. Samples of lung tissue were preserved for evaluation of histopathology and the lesions graded on a subjective scale (0-3 with 0 being normal). Gross and histopathology lesions were detected in all 8 untreated Group 1 dogs with mean subjective lesion scores of 1.8 ± 0.7 (range 1-3) and 3.0 ± 0.0 (range 3), respectively. Gross lesions were observed in 3/8 and histopathology lesions in all 8 of the treated Group 2 dogs with mean subjective lesion scores of 0.4 ± 0.5 (range 0-1) and 1.3 ± 0.4 (range 1-2), respectively. The mean (geometric) number for adult C. vulpis recovered in untreated dogs was 48.3 (range 25-70) compared with 0.65 (range 0-2) in animals treated with Milbemax. The resulting efficacy against C. vulpis was 98.7%. The number of C. vulpis was significantly lower for treated

  14. Toward Measuring Schistosoma Response to Praziquantel Treatment with Appropriate Descriptors of Egg Excretion

    PubMed Central

    Olliaro, Piero L.; Vaillant, Michel; Diawara, Aïssatou; Coulibaly, Jean T.; Garba, Amadou; Keiser, Jennifer; King, Charles H.; Knopp, Stefanie; Landouré, Aly; N’Goran, Eliézer K.; Raso, Giovanna; Scherrer, Alexandra U.; Sousa-Figueiredo, José Carlos; Stete, Katarina; Zhou, Xiao-Nong; Utzinger, Jürg

    2015-01-01

    Background The control of schistosomiasis emphasizes preventive chemotherapy with praziquantel, which aims at decreasing infection intensity and thus morbidity in individuals, as well as transmission in communities. Standardizing methods to assess treatment efficacy is important to compare trial outcomes across settings, and to monitor program effectiveness consistently. We compared customary methods and looked at possible complementary approaches in order to derive suggestions for standardizing outcome measures. Methodology/Principal Findings We analyzed data from 24 studies conducted at African, Asian, and Latin American sites, enrolling overall 4,740 individuals infected with Schistosoma mansoni, S. haematobium, or S. japonicum, and treated with praziquantel at doses of 40–80 mg/kg. We found that group-based arithmetic and geometric means can be used interchangeably to express egg reduction rates (ERR) only if treatment efficacy is high (>95%). For lower levels of efficacy, ERR estimates are higher with geometric than arithmetic means. Using the distribution of individual responses in egg excretion, 6.3%, 1.7% and 4.3% of the subjects treated for S. haematobium, S. japonicum and S. mansoni infection, respectively, had no reduction in their egg counts (ERR = 0). The 5th, 10th, and 25th centiles of the subjects treated for S. haematobium had individual ERRs of 0%, 49.3%, and 96.5%; the corresponding values for S. japonicum were 75%, 99%, and 99%; and for S. mansoni 18.2%, 65.3%, and 99.8%. Using a single rather than quadruplicate Kato-Katz thick smear excluded 19% of S. mansoni-infected individuals. Whilst the effect on estimating ERR was negligible by individual studies, ERR estimates by arithmetic means were 8% lower with a single measurement. Conclusions/Significance Arithmetic mean calculations of Schistosoma ERR are more sensitive and therefore more appropriate to monitor drug performance than geometric means. However, neither are satisfactory to identify

  15. Epidemiologic study and control of Taenia solium infections with praziquantel in a rural village of Mexico.

    PubMed

    Diaz Camacho, S P; Candil Ruiz, A; Suate Peraza, V; Zazueta Ramos, M L; Felix Medina, M; Lozano, R; Willms, K

    1991-10-01

    This study reports the results of an epidemiologic survey for the detection of Taenia solium in a rural village of 559 inhabitants in Sinaloa, Mexico, as well as a large scale treatment of the population with praziquantel. The study was carried out in two stages. In stage 1, serial stool analysis of 392 persons detected a cluster of three T. solium tapeworms. A fourth T. solium tapeworm was detected through a household census, giving a 1.32% prevalence rate for this helminth. Over 70% of the population over five years of age was treated with a 10 mg/kg dose of praziquantel, and no additional tapeworms were found. Environmental studies for the detection of Taenia sp. eggs in soil, water, and and objects from the houses of tapeworm-infected individuals showed only one soil sample containing eggs compatible with Taenia sp. A total of 72 domestic pigs were examined for the presence of cysticerci under the tongue. One animal had cysts, and belonged to a household that had two T. solium tapeworm infections. Stage 2 of the study was carried out one year after large scale antihelminthic treatment (LSAT), and no infections with Taenia sp. eggs were found. No cysticercus-infected pigs were detected. Intestinal parasitosis decreased from 69.2% to 37.5%. It is concluded that LSAT with praziquantel is efficient in decreasing endemic foci of T. solium. Seropositivity to T. solium bladder fluid antigens was tested by enzyme-linked immunosorbent assay and found to be 11% before LSAT and 7% one year later. In family members living with T. solium tapeworm carriers, the number of seropositive individuals was 28%. The relative risk ratio of seropositivity for persons living in the same household with a T. solium tapeworm carrier was 2.95. Positive response was significantly higher in the 30-39-year-old age group, in which 30% were seropositive in stage 1, compared with 7% one year after LSAT. High seropositivity rates were significantly associated with tapeworm clusters as well as

  16. Field evaluation of the efficacy and safety of emodepside plus praziquantel tablets (Profender tablets for dogs) against naturally acquired nematode and cestode infections in dogs.

    PubMed

    Altreuther, Gertraut; Radeloff, Isabelle; LeSueur, Christophe; Schimmel, Annette; Krieger, Klemens J

    2009-08-01

    A controlled, blinded and randomised multicentre field study evaluated the efficacy and safety of a new anthelmintic tablet formulation containing emodepside plus praziquantel (Profender tablets for dogs) in the treatment of gastrointestinal nematode and cestode infections in dogs in France, Germany, Portugal and Slovakia. Dogs positive for nematodes and/or cestodes (demonstrated by faecal egg counts and/or the presence of proglottids) were treated with emodepside plus praziquantel tablets (n = 239) or the reference product containing milbemycin oxime and praziquantel (Milbemax [n = 115]) at the recommended dose rate. Two faecal samples collected between 7 and 13 days after treatment were evaluated for proglottids, nematode and cestode eggs. No suspected adverse drug reactions were observed in the study. The following parasite species were identified: Trichuris vulpis, Toxocara canis, Toxascaris leonina, Uncinaria stenocephala, Ancylostoma caninum, Dipylidium caninum, Taeniidae and Mesocestoides spp. Geometric mean nematode egg counts in dogs treated with emodepside plus praziquantel tablets were reduced by 99.9 % compared with a reduction of 99.6 % for the reference product. Statistical analysis demonstrated noninferiority of investigational versus reference product (p = 0.0342). None of the dogs treated with emodepside plus praziquantel or reference product remained positive for cestodes after treatment. The study demonstrated that emodepside plus praziquantel tablets are safe and highly efficacious against a broad spectrum of nematodes and cestodes under field conditions. PMID:19575222

  17. Praziquantel treatment for yellowtail kingfish (Seriola lalandi): dose and duration safety study.

    PubMed

    Forwood, James M; Bubner, Erin J; Landos, Matt; D'Antignana, Trent; Deveney, Marty R

    2016-02-01

    Regulatory approval is being sought to use praziquantel (PZQ) to treat flukes infecting yellowtail kingfish (YTK), but accurate safety data were not available. We investigated the effect of increased doses or prolonged exposure of orally administered PZQ on YTK by assessing changes in haematological and biochemical characteristics, and mortality. Fish were intubated daily for 3 days with 0, 100, 300 and 500 mg PZQ kg(-1) BW day(-1) or once daily for 9 days at 0 and 100 mg PZQ kg(-1) BW day(-1). Blood was taken 24 h after the cessation of treatment. There was no significant difference between any of the haematological or biochemical indices in YTK treated with PZQ and controls, indicating that PZQ is safe for use at 100 mg PZQ kg(-1) BW day(-1) in YTK and that exposure to high doses or prolonged duration does not have negative effects on the YTK haematological or biochemical parameters we measured. PMID:26314575

  18. The Role of Efflux Pumps in Schistosoma mansoni Praziquantel Resistant Phenotype

    PubMed Central

    Armada, Ana; Belo, Silvana; Carrilho, Emanuel; Viveiros, Miguel; Afonso, Ana

    2015-01-01

    Background Schistosomiasis is a neglected disease caused by a trematode of the genus Schistosoma that is second only to malaria in public health significance in Africa, South America, and Asia. Praziquantel (PZQ) is the drug of choice to treat this disease due to its high cure rates and no significant side effects. However, in the last years increasingly cases of tolerance to PZQ have been reported, which has caused growing concerns regarding the emergency of resistance to this drug. Methodology/Principal Findings Here we describe the selection of a parasitic strain that has a stable resistance phenotype to PZQ. It has been reported that drug resistance in helminths might involve efflux pumps such as members of ATP-binding cassette transport proteins, including P-glycoprotein and multidrug resistance-associated protein families. Here we evaluate the role of efflux pumps in Schistosoma mansoni resistance to PZQ, by comparing the efflux pumps activity in susceptible and resistant strains. The evaluation of the efflux activity was performed by an ethidium bromide accumulation assay in presence and absence of Verapamil. The role of efflux pumps in resistance to PZQ was further investigated comparing the response of susceptible and resistant parasites in the absence and presence of different doses of Verapamil, in an ex vivo assay, and these results were further reinforced through the comparison of the expression levels of SmMDR2 RNA by RT-PCR. Conclusions/Significance This work strongly suggests the involvement of Pgp-like transporters SMDR2 in Praziquantel drug resistance in S. mansoni. Low doses of Verapamil successfully reverted drug resistance. Our results might give an indication that a combination therapy with PZQ and natural or synthetic Pgp modulators can be an effective strategy for the treatment of confirmed cases of resistance to PZQ in S. mansoni. PMID:26445012

  19. Effect of Chemotherapy with Praziquantel on the Production of Cytokines and Morbidity Associated with Schistosomiasis Mansoni▿

    PubMed Central

    Martins-Leite, P.; Gazzinelli, G.; Alves-Oliveira, L. F.; Gazzinelli, A.; Malaquias, L. C. C.; Correa-Oliveira, R.; Teixeira-Carvalho, A.; Silveira, A. M. S.

    2008-01-01

    The objective of the present study was to test the hypothesis that treatment of schistosomiasis mansoni with praziquantel can alter significantly the immune response of patients and generate a reversal of the level of fibrosis. Peripheral blood mononuclear cell (PBMC) samples were collected from, and abdominal ultrasound examinations conducted on, volunteers infected with Schistosoma mansoni and living in an area where the disease is endemic, both prior to and one year after treatment with praziquantel. Subjects were classified into groups according to the level of pathology (i.e., absent, incipient, moderate, or severe fibrosis). PBMCs were stimulated with schistosome soluble egg antigens (SEA), and the levels of production of the cytokines gamma interferon (IFN-γ), tumor necrosis factor alpha, transforming growth factor β, and interleukin-4 (IL-4), IL-10, and IL-13 were determined. The chemotherapy was effective in reducing morbidity, particularly for individuals presenting with severe fibrosis. When levels of cytokine production in posttreatment PBMC cultures stimulated by SEA were categorized as low or high, significant differences in the distribution of IL-13 levels between groups presenting with or not presenting with fibrosis were established. Comparison of pre- and posttreatment SEA-induced cytokine levels in individuals who had experienced no change in the grade of fibrosis following chemotherapy revealed that the level of IFN-γ decreased in subjects with fibrosis whereas that of IL-10 decreased in individuals with and without fibrosis. The data suggest that chemotherapy is effective in reducing the morbidity of the disease and that the level of IL-13 may be a useful indicator of the persistence of fibrosis following treatment. PMID:18519730

  20. New Praziquantel Derivatives Containing NO-donor Furoxans and Related Furazans as Active Agents against Schistosoma mansoni

    PubMed Central

    Guglielmo, Stefano; Cortese, Daniela; Vottero, Francesca; Rolando, Barbara; Kommer, Valerie P.; Williams, David L.; Fruttero, Roberta; Gasco, Alberto

    2014-01-01

    A series of NO-donor praziquantel hybrid compounds was obtained by combining praziquantel (PZQ) and furoxan moieties in a single entity. NO-donor properties of the furoxan derivatives were evaluated by detecting nitrite after incubation of the products in 7.4 pH buffered solution in the presence of L-cysteine. Structurally-related furazans, devoid of NO release capacity, were also synthesized for control purposes. All products were studied for their ability to inhibit recombinant Schistosoma mansoni thioredoxin glutathione reductase (TGR). Mobility and death of adult Schistosoma mansoni worms cultured in the presence of the products were evaluated versus PZQ. Analysis of the results showed that some products were endowed with both PZQ and NO-dependent antiparasitic properties. Compounds 6, 7, 18, and 24 emerged as the most interesting balanced hybrids, worthy of additional study on PZQ-resistant parasites. PMID:25016371

  1. Nanoencapsulated curcumin and praziquantel treatment reduces periductal fibrosis and attenuates bile canalicular abnormalities in Opisthorchis viverrini-infected hamsters.

    PubMed

    Charoensuk, Lakhanawan; Pinlaor, Porntip; Wanichwecharungruang, Supason; Intuyod, Kitti; Vaeteewoottacharn, Kulthida; Chaidee, Apisit; Yongvanit, Puangrat; Pairojkul, Chawalit; Suwannateep, Natthakitta; Pinlaor, Somchai

    2016-01-01

    This study investigated the effects of nanoencapsulated curcumin (NEC) and praziquantel (PZQ) treatment on the resolution of periductal fibrosis (PDF) and bile canalicular (BC) abnormalities in Opisthorchis viverrini infected hamsters. Chronic O. viverrini infection (OV) was initially treated with either PZQ (OP) and subsequently treated with NEC (OP+NEC), curcumin (OP+Cur) or unloaded carriers (OP+carrier) daily for one month. OP+NEC treatment reduced the PDF by suppression of fibrotic markers (hydroxyproline content, α-SMA, CTGF, fibronectin, collagen I and III), cytokines (TGF-β and TNF-α) and TIMP-1, 2, 3 expression and upregulation of MMP-7, 13 genes. Higher activity of NEC in reducing fibrosis compared to curcumin was also demonstrated in in vitro studies. Moreover, OP+NEC also prevented BC abnormalities and upregulated several genes involved in bile acid metabolism. These results demonstrate that NEC and PZQ treatment reduces PDF and attenuates BC defect in experimental opisthorchiasis. From the Clinical Editor: Infection by Opisthorchis viverrini leads to liver fibrosis and affects population in SE Asia. Currently, praziquantel (PZQ) is the drug of choice but this drug has significant side effects. In this study, the authors combined curcumin (NEC) and praziquantel in a nanocarrier to test the anti-oxidative effect of curcumin in an animal model. The encouraging results may pave a way for better treatment in the future. PMID:26542278

  2. Comparative Assessment of Health Benefits of Praziquantel Treatment of Urogenital Schistosomiasis in Preschool and Primary School-Aged Children

    PubMed Central

    Gwisai, Reggis; Mduluza, Takafira; Woolhouse, Mark E. J.; Mutapi, Francisca

    2016-01-01

    Schistosomiasis is a major public health problem in Africa. However, it is only recently that its burden has become recognised as a significant component impacting on the health and development of preschool-aged children. A longitudinal study was conducted in Zimbabwean children to determine the effect of single praziquantel treatment on Schistosoma haematobium-related morbidity markers: microhaematuria, proteinuria, and albuminuria. Changes in these indicators were compared in 1–5 years versus 6–10 years age groups to determine if treatment outcomes differed by age. Praziquantel was efficacious at reducing infection 12 weeks after treatment: cure rate = 94.6% (95% CI: 87.9–97.7%). Infection rates remained lower at 12 months after treatment compared to baseline in both age groups. Among treated children, the odds of morbidity at 12 weeks were significantly lower compared to baseline for proteinuria: odds ratio (OR) = 0.54 (95% CI: 0.31–0.95) and albuminuria: OR = 0.05 (95% CI: 0.02–0.14). Microhaematuria significantly reduced 12 months after treatment, and the effect of treatment did not differ by age group: OR = 0.97 (95% CI: 0.50–1.87). In conclusion, praziquantel treatment has health benefits in preschool-aged children exposed to S. haematobium and its efficacy on infection and morbidity is not age-dependent.

  3. Schistosoma japonicum-infected hamsters (Mesocricetus auratus) used as a model in experimental chemotherapy with praziquantel, artemether, and OZ compounds.

    PubMed

    Xiao, Shu-hua; Mei, Jing-yan; Jiao, Pei-ying

    2011-02-01

    The purpose of the study is to better understand the antischistosomal properties of artemether, praziquantel, and ozonide (OZ) compounds (synthetic trioxolanes, secondary ozonides) in hamster (Mesocricetus auratus) model. A total of 230 male hamsters infected each with 100 Schistosoma japonicum cercariae were used in the study. Groups of five to ten hamsters were treated orally with artemether, praziquantel, and OZ78 or OZ277 7-35 days post-infection at single doses of 50, 100, 150, or 200 mg/kg. Untreated but infected hamsters in each batch of test served as the control. All treated hamsters were sacrificed 4 weeks post-treatment for collection of residual worms using perfusion technique. Nonparametric method (Mann-Whitney test) was used to analyze the data. In groups of five hamsters treated with artemether 7, 14, 21, 28, and 35 days post-infection at single doses of 150 and 200 mg/kg, the difference of mean worm burden between each treated group and control group was statistically significant (P<0.01). Apart from individual group, no difference in mean worm burden between each two groups of them was seen (P>0.05). Further test with various single doses of 50-200 mg/kg confirmed the similar susceptibility of 7-day-old juvenile and 35-day-old adult schistosomes to artemether. After administration of praziquantel 100 mg/kg to groups of five hamsters 7, 21, and 35 days post-infection, higher worm burden reduction of 95.5% was seen in the group with 35-day-old adult schistosomes while in the groups with 7- and 21-day-old juvenile schistosomes, poor efficacy was seen with mean worm burden reductions of 36.6% and 35.6%. In the same batch of hamster treated with praziquantel 200 mg/kg, the moderate effect of the drug against 7- and 21-day-old worms was seen, but their mean worm burden was significantly higher than that of the group with adult schistosomes. In comparison of artemether and praziquantel against various stages of schistosomes, the results further

  4. Analysis of the Presence of Content about Astronomy in a Decade of the National High School Examination (1998-2008). (Spanish Title: Análisis de la Presencia de Contenidos de Astronomía em Uma Década del Examen Nacional de Enseñaza Secundária (1998-2008).) Análise da Presença de Conteúdos de Astronomia em Uma DÉcada do Exame Nacional do Ensino Médio (1998-2008)

    NASA Astrophysics Data System (ADS)

    Gomide, Hanny Angeles; Longhini, Marcos Daniel

    2011-07-01

    In this paper we analyzed the presence of contents of Astronomy in the National High School Examination (ENEM) in its first decade (1998-2008). We verified the number of questions addressing this topic that were present over the years, as well as the most recurrent subjects. We discussed the results from what is proposed by the official documents regarding the teaching of Astronomy in the Elementary and Secondary Education and we entertain future expectations about the presence of contents of this science in future official examinations. En este trabajo realizamos un análisis de la presencia de contenidos de Astronomía em las pruebas del Examen Nacional de Enseñanza Secundaria (ENEM) em su primera década de existência (1998-2008). Contabilizamos la cantidad de preguntas incluyendo este tema que estuvieron presentes en el transcurso de los años, así como los temas más recurrentes. Discutimos los resultados a partir de lo propuesto por los documentos oficiales en relación a la enseñanza de Astronomía en la Educación Básica y elaboramos algunos apuntes sobre futuras expectativas em relación a la presencia de contenidos de esta ciencia en examenes oficiales. No presente trabalho fizemos uma análise da presença de conteúdos de Astronomia nas provas do Exame Nacional do Ensino Médio (ENEM), em sua primeira década de existência (1998-2008). Verificamos a quantidade de questões envolvendo essa temática que estiveram presentes no decorrer dos anos, assim como os temas mais recorrentes. Discutimos os resultados a partir do que é proposto pelos documentos oficiais em relação ao ensino de Astronomia na Educação Básica e tecemos alguns apontamentos sobre a expectativa futura quanto à presença de conteúdos dessa ciência nesse exame oficial.

  5. Drug efficacy of praziquantel and albendazole in school children in Mwea Division, Central Province, Kenya.

    PubMed

    Kihara, J H; Muhoho, N; Njomo, D; Mwobobia, I K; Josyline, K; Mitsui, Y; Awazawa, T; Amano, T; Mwandawiro, C

    2007-06-01

    The objective of this research was to assess drug efficacy in school children after mass chemotherapy with praziquantel and albendazole conducted in Mwea Division, Kirinyaga District, Central Kenya in 2004. In total 2300 children aged between 4 and 18 years in five primary schools were selected for the study. Before mass chemotherapy, prevalence of infection was 47.4% for Schistosoma mansoni, 16.7% for Necator americanus, 1.6% for Ascaris lumbricoides, and 0.8% for Trichuris trichiura. Post-treatment stool examination was carried out 8 weeks later, and a total of 1942 stool samples were collected. Prevalence decreased to 8.6% for S. mansoni, 0.2% for N. americunus, 0 for A. lumbricoides, and 0.6% for T. trichiura. Efficacy was good for S. mansoni and N. americanus (92.6% and 95.0%, respectively). Results of the first round of treatment of school-age children in Mwea indicate a good reduction in parasite burden. PMID:17572368

  6. An Artemisinin Derivative of Praziquantel as an Orally Active Antischistosomal Agent

    PubMed Central

    Chen, Jinglei; Sun, Huan; Qiao, Chunhua; Xia, Chao-ming

    2014-01-01

    Background Schistosomiasis is a major health problem in tropical and sub-tropical areas caused by species of trematode belonging to the genus Schistosoma. The treatment and control of this disease has been relying on the use of a single drug praziquantel. However, the drug resistance concern urged the development of new drugs against schistosoma. Here, we report our systematic biological evaluation of DW-3-15, a new lead compound developed based on our conjugation design rationale as an effective anti-schistosomal agent. Methodology/Principal Findings The antischistosomal activity of DW-3-15 was systematically evaluated in S. japonicum infected mouse model for its stage-sensitivity and dose response. The results revealed that DW-3-15 exhibited 60–85% worm reduction rate against different development stage of worm. Scanning electron microscopy (SEM) observation indicated that DW-3-15 may damage to the tegument of male schistosomes. Conclusions/Significance Our results demonstrated that DW-3-15 showed potent anti-schistosomal activities in vivo. The results strongly support our conjugation design strategy of artemisinin analogs and further development of DW-3-15 as a new lead compound as anti-schistosomal agent. PMID:25386745

  7. Repeated praziquantel treatments remodel the genetic and spatial landscape of schistosomiasis risk and transmission.

    PubMed

    Barbosa, Lúcio M; Reis, Eliana A; Dos Santos, Cláudio R A; Costa, Jackson M; Carmo, Theomira M; Aminu, Peace T; Pitanga, Thassila N; Ponce-Terashima, Rafael; Blank, Walter A; Silva, Luciano K; Reis, Mitermayer G; Blanton, Ronald E

    2016-05-01

    Repeated treatments with praziquantel reduce schistosomiasis prevalence and morbidity, but transmission persists and populations often recover within a few years. To identify factors associated with persistence, we surveyed and treated all identified Schistosoma mansoni infections in two rural Brazilian communities (Jenipapo and Volta do Rio) in 2009, 2012 and 2013. Eggs were collected from all infected individuals and genotyped with 11 microsatellite markers to evaluate parasite differentiation and diversity. After successive rounds of community-wide treatment, prevalence decreased from 45% to 24% then 16%. Intensity of infection decreased by 57% over this period, and the number of eggs transmitted to the environment decreased by 92%. During all time periods the majority of eggs were excreted by those >15years of age. The incidence was 23% in 2012 and 15% in 2013, consistent with a decrease in transmission. There was little immigration or gene flow over a distance of 6km. On reinfection, infrapopulations were moderately differentiated indicating that pretreatment multilocus genotypes were not fully reacquired. The effective population size responded to census population decline more rapidly than differentiation. Reinfection was concentrated in the downstream portion of Jenipapo, consistent with the observed increased human fecal contamination. At this scale and in this area S. mansoni infections exist on a fragmented landscape with a highly focal pattern of transmission that may facilitate future elimination. PMID:26953255

  8. Pharmacokinetics of a new ivermectin/praziquantel suspension after intramuscular administration in sheep.

    PubMed

    Tang, Shusheng; Chen, Linlin; Qian, Minyi; Hao, Lihua; Xiao, Xilong

    2016-05-15

    A new oil suspension containing 0.10% ivermectin (IVM) and 15% praziquantel (PZQ) (Tivm+pzq) for intramuscular injection was developed for sheep, and its pharmacokinetics was investigated in sheep. The quality of the new product met the technical standards set by the Ministry of Agriculture of the People's Republic of China. In pharmacokinetics, the commercially available single-component products approved by the Chinese Ministry of Agriculture and widely used in the livestock industry in China were selected as reference products (Rivm and Rpzq). The results showed that all of the IVM pharmacokinetic parameters of Tivm+pzq were similar to those of the reference. However, after adminstraion of Tivm+pzq, mean residence time (MRT) and plasma elimination half-life (t1/2z) were 20.36h and 11.65h, which were 2.61 and 3.22 times longer than those of Rpzq (7.81h and 3.62h). In summary, the MRT and t1/2z of PZQ in Tivm+pzq were prolonged and IVM pharmacokinetic parameters were similar to commerical product, therefore the new injection may be an alternative choice for sheep to control parasites sensitive to IVM and PZQ. PMID:27084471

  9. Elucidating the influence of praziquantel nanosuspensions on the in vivo metabolism of Taenia crassiceps cysticerci.

    PubMed

    Silva, Luciana Damacena; Arrúa, Eva Carolina; Pereira, Dayanne Amaral; Fraga, Carolina Miguel; Costa, Tatiane Luiza da; Hemphill, Andrew; Salomon, Claudio Javier; Vinaud, Marina Clare

    2016-09-01

    The aim of this work was to develop nanosuspensions of praziquantel (PZQ) and to evaluate their influence on the energetic metabolism of cysticerci inoculated in BALB/c mice. We analyzed metabolic alterations of glycolytic pathways and the tricarboxylic acid cycle in the parasite. The nanosuspensions were prepared by precipitation and polyvinyl alcohol (PVA), poloxamer 188 (P188) and poloxamer 407 (P407) were used as stabilizers. Nanosuspension prepared with PVA had a particle size of 100nm, while P188- and P407-based nanosuspensions had particle sizes of 74nm and 285nm, respectively. The zeta potential was -8.1, -8.6, and -13.2 for the formulations stabilized with PVA, P188 and P407, respectively. Treatments of T. crassiceps cysticerci-infected mice resulted in an increase in glycolysis organic acids, and enhanced the partial reversion of the tricarboxylic acid cycle, the urea cycle and the production of ketonic bodies in the parasites when compared to the groups treated with conventional PZQ. These data suggest that PZQ nanosuspensions greatly modified the energetic metabolism of cysticerci in vivo. Moreover, the remarkable metabolic alterations produced by the stabilizers indicate that further studies on nanoformulations are required to find potentially suitable nanomedicines. PMID:27269203

  10. Ca2+ channels and Praziquantel: a view from the free world

    PubMed Central

    Chan, John D.; Zarowiecki, Magdalena; Marchant, Jonathan S.

    2012-01-01

    Targeting the cellular Ca2+ channels and pumps that underpin parasite Ca2+ homeostasis may realize novel antihelmintic agents. Indeed, the antischistosomal drug praziquantel (PZQ) is a key clinical agent that has been proposed to work in this manner. Heterologous expression data has implicated an action of PZQ on voltage-operated Ca2+ channels, although the relevant in vivo target of this drug has remained undefined over three decades of clinical use. The purpose of this review is to bring new perspective to this issue by discussing the potential utility of free-living planarian flatworms for providing new insight into the mechanism of PZQ action. First, we discuss in vivo functional genetic data from the planarian system that broadly supports the molecular data collected in heterologous systems and the ‘Ca2+ hypothesis’ of PZQ action. On the basis of these similarities we highlight our current knowledge of platyhelminth voltage operated Ca2+ channels, their unique molecular pharmacology and the downstream functional PZQ interactome engaged by dysregulation of Ca2+ influx that has potential to yield novel antischistosomal targets. Overall the broad dataset underscore a common theme of PZQ-evoked disruptions of Ca2+ homeostasis in trematodes, cestodes and turbellarians, and showcase the utility of the planarian model for deriving insight into drug action and targets in parasitic flatworms. PMID:23246536

  11. [Differences in the dynamics of the eosinophilia, blood immunoglobulin E and the level of circulating immune complexes in patients with chronic opisthorchiasis treated with different doses of praziquantel].

    PubMed

    Legon'kov, Iu A; Ozeretskovskaia, N N; Gervazieva, V B; Ovsiannikova, I G; Bronshteĭn, A M

    1992-01-01

    Sixty patients with a chronic Opisthorchis felineus infection were administered one-day therapy with praziquantel in doses 25, 40, or 60-75 mg/kg b. m. The former two doses of the drug did not much improve the levels of the examined immunologic parameters. In patients treated with the highest dose of praziquantel a significant decrease of the total and specific IgE and CIC levels, reaching that in the reference groups, was observed in 6-8 months after the treatment, this indicating a 92% efficacy of the drug in this group of patients. PMID:1299753

  12. Infection with Opisthorchis viverrini and use of praziquantel among a working-age population in northeast Thailand.

    PubMed

    Saengsawang, Phubet; Promthet, Supannee; Bradshaw, Peter

    2013-01-01

    Infection with Opisthorchis viverrini (OV) due to eating certain traditional freshwater fish dishes is the principal risk factor for cholangiocarcinoma in Northeast Thailand where the infection is endemic and the incidence of this form of primary liver cancer has been the highest in the world. This paper is the second report of a prospective research project to monitor the impacts of a national liver fluke control programme in a rural community of Northeast Thailand. A sample of 684 villagers aged 20-65 years completed an interview questionnaire and were tested for infection using the Kato thick smear technique. The questionnaire was designed for the exploration of associations between OV infection, previous treatment with praziquantel, and knowledge and beliefs about the drug. The data were analysed using descriptive statistics and multiple logistic regression. The overall prevalence of OV infection was 37.2% and was highest in the 20-35 year age group, in those with a university degree and in those employed in the government sector. As many as 91.8% reported eating fish dishes known to place them at risk of infection. In the multiple regression analysis, previous use of praziquantel and lack of knowledge about whether or not the drug has a protective effect against re-infection were the only factors related to OV infection (ORadj= 2.31, 95%CI =1.40-3.79 and ORadj= 1.95, 95%CI= 1.24-3.05). The findings were discussed in terms of the possibly unwise dependency on praziquantel as a primary element in a control programme. PMID:23803062

  13. Efficacy of combined antiparasitic therapy with praziquantel and albendazole for neurocysticercosis: a double-blind, randomised controlled trial

    PubMed Central

    Garcia, Hector H; Gonzales, Isidro; Lescano, Andres G; Bustos, Javier A; Zimic, Mirko; Escalante, Diego; Saavedra, Herbert; Gavidia, Martin; Rodriguez, Lourdes; Najar, Enrique; Umeres, Hugo; Pretell, E Javier

    2014-01-01

    Summary Background Neurocysticercosis causes a substantial burden of seizure disorders worldwide. Treatment with either praziquantel or albendazole has suboptimum efficacy. We aimed to establish whether combination of these drugs would increase cysticidal efficacy and whether complete cyst resolution results in fewer seizures. We added an increased dose albendazole group to establish a potential effect of increased albendazole concentrations. Methods In this double-blind, placebo-controlled, phase 3 trial, patients with viable intraparenchymal neurocysticercosis were randomly assigned to receive 10 days of combined albendazole (15 mg/kg per day) plus praziquantel (50 mg/kg per day), standard albendazole (15 mg/kg per day), or increased dose albendazole (22·5 mg/kg per day). Randomisation was done with a computer generated schedule balanced within four strata based on number of cysts and concomitant antiepileptic drug. Patients and investigators were masked to group assignment. The primary outcome was complete cyst resolution on 6-month MRI. Enrolment was stopped after interim analysis because of parasiticidal superiority of one treatment group. Analysis excluded patients lost to follow-up before the 6-month MRI. This trial is registered with ClinicalTrials.gov, number NCT00441285. Findings Between March 3, 2010 and Nov 14, 2011, 124 patients were randomly assigned to study groups (41 to receive combined albendazole plus praziquantel [39 analysed], 43 standard albendazole [41 analysed], and 40 increased albendazole [38 analysed]). 25 (64%) of 39 patients in the combined treatment group had complete resolution of brain cysts compared with 15 (37%) of 41 patients in the standard albendazole group (rate ratio [RR] 1·75, 95% CI 1·10–2·79, p=0·014). 20 (53%) of 38 patients in the increased albendazole group had complete cyst resolution at 6-month MRI compared with 15 (37%) of 41 patients in the standard albendazole group (RR 1·44, 95% CI 0·87–2·38, p=0·151

  14. Evaluation of Oxfendazole, Praziquantel and Albendazole against Cystic Echinococcosis: A Randomized Clinical Trial in Naturally Infected Sheep

    PubMed Central

    Gavidia, Cesar M.; Gonzalez, Armando E.; Barron, Eduardo A.; Ninaquispe, Berenice; Llamosas, Monica; Verastegui, Manuela R.; Robinson, Colin; Gilman, Robert H.

    2010-01-01

    Background Cystic Echinococosis (CE) is a zoonotic disease caused by larval stage Echinococcus granulosus. We determined the effects of high dose of Oxfendazole (OXF), combination Oxfendazole/Praziquantel (PZQ), and combination Albendazole (ABZ)/Praziquantel against CE in sheep. Methodology/Principal Findings A randomized placebo-controlled trial was carried out on 118 randomly selected ewes. They were randomly assigned to one of the following groups: 1) placebo; 2) OXF 60 mg/Kg of body weight (BW) weekly for four weeks; 3) ABZ 30 mg/Kg BW + PZQ 40 mg/Kg BW weekly for 6 weeks, and 4) OXF 30 mg/Kg BW+ PZQ 40 mg/Kg BW biweekly for 3 administrations (6 weeks). Percent protoscolex (PSC) viability was evaluated using a 0.1% aqueous eosin vital stain for each cyst. “Noninfective” sheep were those that had no viable PSCs; “low-medium infective” were those that had 1% to 60% PSC viability; and “high infective” were those with more than 60% PSC viability. We evaluated 92 of the 118 sheep. ABZ/PZQ led the lowest PSC viability for lung cysts (12.7%), while OXF/PZQ did so for liver cysts (13.5%). The percentage of either “noninfective” or “low-medium infective” sheep was 90%, 93.8% and 88.9% for OXF, ABZ/PZQ and OXF/PZQ group as compared to 50% “noninfective” or “low-medium infective” for placebo. After performing all necropsies, CE prevalence in the flock of sheep was 95.7% (88/92) with a total number of 1094 cysts (12.4 cysts/animal). On average, the two-drug-combination groups resulted pulmonary cysts that were 6 mm smaller and hepatic cysts that were 4.2 mm smaller than placebo (p<0.05). Conclusions/Significance We demonstrate that Oxfendazole at 60 mg, combination Oxfendazole/Praziquantel and combination Albendazole/Praziquantel are successful schemas that can be added to control measures in animals and merits further study for the treatment of animal CE. Further investigations on different schedules of monotherapy or combined chemotherapy are

  15. Additional evidence that rosacea pathogenesis may involve demodex: new information from the topical efficacy of ivermectin and praziquantel.

    PubMed

    Abokwidir, Manal; Fleischer, Alan B

    2015-09-01

    Additional evidence that Demodex folliculorum may contribute to the pathogenesis of papulopustular rosacea are new studies of two topical antiparasitic agents. Ivermectin and praziquantel have recently been shown to be effective in decreasing the severity of papulopustular rosacea. These two agents significantly differ in molecular structure, but yield similar antiparasitic mechanisms of action. Higher numbers of Demodex mites are found in the skin of patients with rosacea than in people with normal skin. If Demodex play a role in pathogenesis, then hypersensitivity to the mites, their flora, or their products could explain the observed efficacy of antidemodectic therapy. PMID:26437294

  16. Initial experiences with praziquantel in the treatment of human infections due to Schistosoma haematobium

    PubMed Central

    Davis, A.; Biles, J. E.; Ulrich, A.-M.

    1979-01-01

    Initial studies of the tolerance and efficacy of praziquantel in the treatment of human infections due to Schistosoma haematobium were conducted at the WHO Tropical Diseases Research Centre, Ndola, Zambia. The first stage of the trial was a double-blind assessment against placebo of the tolerance and efficacy of oral doses of 1×20, 2×20, or 3×20 mg/kg in patients with a minimum schistosome egg excretion of 50 per random 10-ml sample of urine. Later a single-blind trial was carried out of the efficacy of three oral doses, each of 20 mg/kg, given at 4-hour intervals, or of a single oral dose of 50 mg/kg. In 79 young Zambians with S. haematobium infections (and often other parasitic infections), patient tolerance to the drug was very good, only minor post-treatment symptoms of intermittent epigastric pain, anorexia, and headache being noted, all of short duration. No changes of clinical relevance were detected in the results of a battery of haematological and biochemical tests. Post-treatment eosinophilia occurred in 42% of drug-treated patients but also in 30% of those given placebo. Serial electrocardiograms revealed no changes of significance. At six months after treatment, of 73 patients followed up, only 1 case of parasitological failure was detected. At one year, 66 (83.5%) of 79 patients with S. haematobium infection were followed up and 2 (2.5%) parasitological failures were detected. Two years after treatment, 45 (57%) of 79 patients with S. haematobium showed negative urines, 7 (9%) had positive hatching tests, and 27 (34%) were absent. PMID:396053

  17. Pharmacokinetics and residue depletion of praziquantel in rice field eels Monopterus albus.

    PubMed

    Xu, Ning; Dong, Jing; Yang, Yibin; Ai, Xiaohui

    2016-04-12

    We investigated the pharmacokinetic characteristics of praziquantel (PZQ) in rice field eels Monopterus albus. Pharmacokinetic parameters were determined following a single intravenous administration (5 mg kg(-1) body weight [bw]) and a single oral administration (10 mg kg(-1) bw) at 22.0 ± 0.7°C. We also evaluated residue depletion in tissues following daily administration of PZQ (10 mg kg(-1) bw) that was given orally for 3 consecutive days at 22.0 ± 0.7°C. Following intravenous treatment, the plasma concentration-time curve was best described by a 3-compartment open model, with distribution half-life (t(1/2α)), elimination half-life (t(1/2β)), and area under the concentration-time curve (AUC) of 0.54 h, 17.10 h, and 14505.12 h µg l(-1), respectively. After oral administration, the plasma concentration-time curve was best described by a 1-compartment open model with first-order absorption, with absorption half-life (t(1/2Ka)), elimination half-life (t(1/2Ke)), peak concentration (C(max)), time-to-peak concentration (T(max)), and AUC estimated to be 2.28 h, 6.66 h, 361.29 µg l(-1), 5.36 h, and 6065.46 h µg l(-1), respectively. The oral bioavailability (F) was 20.9%. With respect to residue depletion of PZQ, the t(1/2β) values of muscle, skin, liver, and kidney were 20.2, 28.4, 14.9, and 54.1 h, respectively. Our results indicated rapid absorption, rapid elimination, and low bioavailability of PZQ in rice field eels at the tested dosing conditions. PMID:27068504

  18. Efficacy of Praziquantel against Schistosoma haematobium in Dulshatalo village, western Ethiopia

    PubMed Central

    2013-01-01

    Background Praziquantel (PZQ) is the drug of choice for treatment of all human schistosomes. It is used in population based targeted or mass deworming strategies in several countries. The effect of PZQ on S. hematobium has not been studied in Ethiopia. The objective of this study was to determine the efficacy of PZQ against S. haematobium in Dulshatalo village, western Ethiopia. Methods A prospective study was conducted from October to December, 2007. Urine samples from 341 residents were collected and screened for haematuria and proteinuria using urinalysis dipstick. S. haematobium eggs were detected and quantified using filtration techniques. The participants who were positive for haematuria were treated with a standard dose of PZQ (40 mg/kg). Data on pre and 24 hours post treatment symptoms were collected via questionnaire. Urine samples were also collected 7 weeks after treatment and examined to assess the cure and the egg reduction rates. Results The prevalence of S. haematobium among the study participants was 57.8% (197/341). Haematuria was detected in 234 (68.6%) of the study participants. For PZQ efficacy asessment, 152 of the treated participants were considered. The presence of S. haemetaobium eggs showed statistically significant association (p < 0.05) with haematuria and proteinuria. Seven weeks post treatment, the extent of haematuria and proteinuria decreased from 100% to 40.8% and 94.07% to 48.7%, respectively. The cure and the parasitological egg reduction rates seven weeks post treatment were 86% and 85%, respectively. Post treatment symptoms revealed a wide range of side effects including straining, abdominal pain, nausea and headache. Conclusions There were marked cure and egg reduction rates, together with mild and short lived side effects of PZQ for treatment of S. haematobium, in this study. PMID:24073761

  19. Synergy of Omeprazole and Praziquantel In Vitro Treatment against Schistosoma mansoni Adult Worms

    PubMed Central

    Anderson, Leticia; Venancio, Thiago M.; Nakaya, Helder I.; Miyasato, Patrícia A.; Rofatto, Henrique K.; Zerlotini, Adhemar; Nakano, Eliana; Oliveira, Guilherme; Verjovski-Almeida, Sergio

    2015-01-01

    Background Treatment and morbidity control of schistosomiasis relies on a single drug, praziquantel (PZQ), and the selection of resistant worms under repeated treatment is a concern. Therefore, there is a pressing need to understand the molecular effects of PZQ on schistosomes and to investigate alternative or synergistic drugs against schistosomiasis. Methodology We used a custom-designed Schistosoma mansoni expression microarray to explore the effects of sublethal doses of PZQ on large-scale gene expression of adult paired males and females and unpaired mature females. We also assessed the efficacy of PZQ, omeprazole (OMP) or their combination against S. mansoni adult worms with a survival in vitro assay. Principal Findings We identified sets of genes that were affected by PZQ in paired and unpaired mature females, however with opposite gene expression patterns (up-regulated in paired and down-regulated in unpaired mature females), indicating that PZQ effects are heavily influenced by the mating status. We also identified genes that were similarly affected by PZQ in males and females. Functional analyses of gene interaction networks were performed with parasite genes that were differentially expressed upon PZQ treatment, searching for proteins encoded by these genes whose human homologs are targets of different drugs used for other diseases. Based on these results, OMP, a widely prescribed proton pump inhibitor known to target the ATP1A2 gene product, was chosen and tested. Sublethal doses of PZQ combined with OMP significantly increased worm mortality in vitro when compared with PZQ or OMP alone, thus evidencing a synergistic effect. Conclusions Functional analysis of gene interaction networks is an important approach that can point to possible novel synergistic drug candidates. We demonstrated the potential of this strategy by showing that PZQ in combination with OMP displayed increased efficiency against S. mansoni adult worms in vitro when compared with

  20. Comparative clinical studies of nitazoxanide, albendazole and praziquantel in the treatment of ascariasis, trichuriasis and hymenolepiasis in children from Peru.

    PubMed

    Juan, Jave Ortiz; Lopez Chegne, Nicholas; Gargala, Gilles; Favennec, Loic

    2002-01-01

    Three randomized clinical studies were conducted in 2000 to evaluate the efficacy of nitazoxanide paediatric suspension compared to albendazole in the treatment of ascariasis and trichuriasis and praziquantel in the treatment of hymenolepiasis in children from Cajamarca, Peru. Nitazoxanide was administered at a dose of 100 mg (age 1-3 years) or 200 mg (age 4-11 years) twice daily for 3 days, albendazole as a 400-mg single dose and praziquantel as a 25-mg/kg single dose. Post-treatment parasitological examinations were carried out on 3 faecal samples, each collected on a different day between 21 and 30 days following initiation of treatment. Nitazoxanide cured 89% (25/28), 89% (16/18) and 82% (32/39) of the cases of ascariasis, trichuriasis and hymenolepiasis respectively compared with 91% (32/35), 58% (11/19) and 96% (47/49) for the comparator drugs. Each of the drugs produced egg reduction rates in excess of 98%. There were no significant adverse events or abnormalities in haematology or clinical chemistry values or urinalysis. PMID:12055813

  1. Polymeric Nanostructured Systems for Liquid Formulation of Praziquan-tel: Development and in vitro Assessment.

    PubMed

    de Campos, Vania E B; Silva, Julia A; Ricci-Júnior, Eduardo; Mansur, Claudia R E; Conti, Denise S; da Rocha, Sandro R P

    2016-01-01

    Praziquantel (PZQ) is widely used in the treatment of several parasitic infections in both humans and animals, and is the first choice in the treatment of Schistosomiasis in humans. However, PZQ is a hydrophobic drug, and its low aqueous solubility has been a significant barrier to the development of oral liquid formulations that may provide improved bioavailability, pharmacokinetic profile, and compliance. The aim of this study was thus (i) to develop an oil-in-water (O/W) nanoemulsion(NE)-based platform for the delivery of PZQ in liquid form; (ii) to study the transport of PZQ formulated in NEs across an in vitro model of the intestinal epithelium; and (iii) to determine the toxicity profile of the NEs and their individual components on the model epithelium. We also sought to compare the toxicity and transport profiles of the proposed formulations, with those of PZQ in a solid nanostructured particle system - PZQ encapsulated within poly(lactic acid-co-glycolic acid) (PLGA) nanoparticles (NPs). Two essential oils were selected as the oil phase in the NEs, namely clove and orange. The NEs were prepared with selected non-ionic surfactants and had high solubilization capacity towards PZQ, and average diameters well below 100nm. The NEs also showed long term physical stability at both simulated physiological and gastric conditions. NEs with clove oil (NEC-PZQ) were observed to have a lower cytotoxic profile when compared to the orange oil NEs (NEO-PZQ). The results also showed that the transport of PZQ formulated within such nanostructured systems was much greater and larger rates across confluent and polarized Caco-2 monolayers when compared to free PZQ. Interestingly, little difference in PZQ transport between the NEs and NPs was observed. These results point to NEs as potentially viable strategies for the liquid formulation of PZQ in particular, and more broadly to the formulation of other hydrophobic therapeutics that may be employed in the fight against

  2. Praziquantel in a Clay Nanoformulation Shows More Bioavailability and Higher Efficacy against Murine Schistosoma mansoni Infection

    PubMed Central

    Mohamed, Wael S.; Nasr, Hanaa E.; El-Lakkany, Naglaa M.; Seif el-Din, Sayed H.; Botros, Sanaa S.

    2015-01-01

    Consideration of existing compounds always simplifies and shortens the long and difficult process of discovering new drugs specifically for diseases of developing countries, an approach that may add to the significant potential cost savings. This study focused on improving the biological characteristics of the already-existing antischistosomal praziquantel (PZQ) by incorporating it into montmorillonite (MMT) clay as a delivery carrier to overcome its known bioavailability drawbacks. The oral bioavailability of a PZQ-MMT clay nanoformulation and its in vivo efficacy against Schistosoma mansoni were investigated. The PZQ-MMT clay nanoformulation provided a preparation with a controlled release rate, a decrease in crystallinity, and an appreciable reduction in particle size. Uninfected and infected mice treated with PZQ-MMT clay showed 3.61- and 1.96-fold and 2.16- and 1.94-fold increases, respectively, in area under the concentration-time curve from 0 to 8 h (AUC0–8) and maximum concentration of drug in serum (Cmax), with a decrease in elimination rate constant (kel) by 2.84- and 1.35-fold and increases in the absorption rate constant (ka) and half-life (t1/2e) by 2.11- and 1.51-fold and 2.86- and 1.34-fold, respectively, versus the corresponding conventional PZQ-treated groups. This improved bioavailability has been expressed in higher efficacy of the drug, where the dose necessary to kill 50% of the worms was reduced by >3-fold (PZQ 50% effective dose [ED50] was 20.25 mg/kg of body weight for PZQ-MMT clay compared to 74.07 mg/kg for conventional PZQ), with significant reduction in total tissue egg load and increase in total immature, mature, and dead eggs in most of the drug-treated groups. This formulation showed better bioavailability, enhanced antischistosomal efficacy, and a safer profile despite the longer period of residence in the systemic circulation. Although the conventional drug's toxicity was not examined, animal mortality rates were not different

  3. Solid lipid nanoparticle suspension enhanced the therapeutic efficacy of praziquantel against tapeworm

    PubMed Central

    Xie, Shuyu; Pan, Baoliang; Shi, Baoxin; Zhang, Zhuangzhi; Zhang, Xu; Wang, Ming; Zhou, Wenzhong

    2011-01-01

    Hydatid disease caused by tapeworm is an increasing public health and socioeconomic concern. In order to enhance the therapeutic efficacy of praziquantel (PZQ) against tapeworm, PZQ-loaded hydrogenated castor oil solid lipid nanoparticle (PZQ-HCO-SLN) suspension was prepared by a hot homogenization and ultrasonication method. The stability of the suspension at 4°C and room temperature was evaluated by the physicochemical characteristics of the nanoparticles and in-vitro release pattern of the suspension. Pharmacokinetics was studied after subcutaneous administration of the suspension in dogs. The therapeutic effect of the novel formulation was evaluated in dogs naturally infected with Echinococcus granulosus. The results showed that the drug recovery of the suspension was 97.59% ± 7.56%. Nanoparticle diameter, polydispersivity index, and zeta potential were 263.00 ± 11.15 nm, 0.34 ± 0.06, and −11.57 ± 1.12 mV, respectively and showed no significant changes after 4 months of storage at both 4°C and room temperature. The stored suspensions displayed similar in-vitro release patterns as that of the newly prepared one. SLNs increased the bioavailability of PZQ 5.67-fold and extended the mean residence time of the drug from 56.71 to 280.38 hours. Single subcutaneous administration of PZQ-HCO-SLN suspension obtained enhanced therapeutic efficacy against tapeworm in infected dogs. At the dose of 5 mg/kg, the stool-ova reduction and negative conversion rates and tapeworm removal rate of the suspension were 100%, while the native PZQ were 91.55%, 87.5%, and 66.7%. When the dose reduced to 0.5 mg/kg, the native drug showed no effect, but the suspension still got the same therapeutic efficacy as that of the 5 mg/kg native PZQ. These results demonstrate that the PZQ-HCO-SLN suspension is a promising formulation to enhance the therapeutic efficacy of PZQ. PMID:22072873

  4. Performance and Safety of Praziquantel for Treatment of Intestinal Schistosomiasis in Infants and Preschool Children

    PubMed Central

    Sousa-Figueiredo, José C.; Betson, Martha; Atuhaire, Aaron; Arinaitwe, Moses; Navaratnam, Annalan M. D.; Kabatereine, Narcis B.; Bickle, Quentin; Stothard, J. Russell

    2012-01-01

    Background In 2012 the WHO formally recognised that infants and preschool children are at significant risk of schistosomiasis and qualify for treatment with praziquantel (PZQ). Targeted surveys determining both the performance and safety of this drug are now needed in endemic areas. We have formally assessed parasitological cure and putative side-effects in a prospective cohort of Schistosoma mansoni-infected children (aged 5 months–7 years old) in lakeshore settings of Uganda. Methodology/Principal Findings From a total of 369 children found to be egg-patent for intestinal schistosomiasis, 305 were followed-up three to four weeks after PZQ treatment and infection status re-assessed. Separately, a previously tested side-effect questionnaire was employed before and 24 hours after PZQ treatment to assess incidence and amelioration of symptoms in young children and their mothers. While the overall observed parasitological cure was 56.4%, a significant difference was found between a sub-set of children who had a history of multiple PZQ treatments (between one and four in an 18 month period), where cure rate was 41.7%, and those who had never received treatment (cure rate was 77·6%). PZQ proved to be safe, with only mild reported side effects which cleared within a month after treatment. Prevalence of reported symptoms was significantly lower in children than in mothers, and fewer side-effects were reported upon subsequent rounds of PZQ treatment. Conclusion/Significance Our findings show that PZQ treatment of young children resulted in satisfactory cure rates, and marked reduction in egg-output, with only mild and transient reported side-effects. However, the cure rate is clearly lower in younger children and those with history of previous treatment. Cure rate, but not egg reduction rate, was also lower in children with heavier pre-intervention infection intensity. With chemotherapy now recommended as a long-term strategy for disease control in young children

  5. Sensitivity and Specificity of Multiple Kato-Katz Thick Smears and a Circulating Cathodic Antigen Test for Schistosoma mansoni Diagnosis Pre- and Post-repeated-Praziquantel Treatment

    PubMed Central

    Lamberton, Poppy H. L.; Kabatereine, Narcis B.; Oguttu, David W.; Fenwick, Alan; Webster, Joanne P.

    2014-01-01

    Background Two Kato-Katz thick smears (Kato-Katzs) from a single stool are currently recommended for diagnosing Schistosoma mansoni infections to map areas for intervention. This ‘gold standard’ has low sensitivity at low infection intensities. The urine point-of-care circulating cathodic antigen test (POC-CCA) is potentially more sensitive but how accurately they detect S. mansoni after repeated praziquantel treatments, their suitability for measuring drug efficacy and their correlation with egg counts remain to be fully understood. We compared the accuracies of one to six Kato-Katzs and one POC-CCA for the diagnosis of S. mansoni in primary-school children who have received zero to ten praziquantel treatments. We determined the impact each diagnostic approach may have on monitoring and evaluation (M&E) and drug-efficacy findings. Method/Principle Findings In a high S. mansoni endemic area of Uganda, three days of consecutive stool samples were collected from primary school-aged children (six - 12 years) at five time-points in year one: baseline, one-week-post-, four-weeks-post-, six-months-post-, and six-months-one-week-post-praziquantel and three time-points in years two and three: pre-, one-week-post- and four-weeks-post-praziquantel-treatment/retreatment (n = 1065). Two Kato-Katzs were performed on each stool. In parallel, one urine sample was collected and a single POC-CCA evaluated per child at each time-point in year one (n = 367). At baseline, diagnosis by two Kato-Katzs (sensitivity = 98.6%) or one POC-CCA (sensitivity = 91.7%, specificity = 75.0%) accurately predicted S. mansoni infections. However, one year later, a minimum of three Kato-Katzs, and two years later, five Kato-Katzs were required for accurate diagnosis (sensitivity >90%) and drug-efficacy evaluation. The POC-CCA was as sensitive as six Kato-Katzs four-weeks-post and six-months-post-treatment, if trace readings were classified as positive. Conclusions

  6. Efficacy of Emodepside/Praziquantel Spot-on (Profender®) against adult Aelurostrongylus abstrusus Nematodes in Experimentally Infected Cats.

    PubMed

    Böhm, Claudia; Wolken, Sonja; Schnyder, Manuela; Basso, Walter; Deplazes, Peter; Di Cesare, Angela; Deuster, Katrin; Schaper, Roland

    2015-08-01

    The adulticidal efficacy of a topical combination of emodepside 2.1 % (w/v) plus praziquantel 8.6 % (w/v) (Profender® spot-on for cats, Bayer) against adult Aelurostrongylus abstrusus nematodes was evaluated in two randomised, placebo-controlled laboratory efficacy studies. Each study involved 16 cats experimentally inoculated with L3 (800 and 600 each in studies no. 1 and 2, respectively) and randomised into two study groups of 8 cats each after onset of patency. While cats in the treatment group in study no. 1 received a single spot-on application at the minimum therapeutic dose (3 mg/kg emodepside and 12 mg/kg praziquantel), cats in study no. 2 were treated twice with an interval of 14 days. The faecal output of first stage larvae was monitored throughout the study. Necropsy was conducted 4 or 5 weeks after the (first) treatment and the worm counts were used for efficacy calculations. The control groups showed a geometric mean of the total worm count (live and dead worms) of 28.8 (study no. 1) and 17.6 (study no. 2), respectively. All control animals were infected. While the single treatment in study no. 1 resulted in a reduction of the total worm burden by 73.0 % (p = 0.0070), the treatment protocol in study no. 2 was 99.2 % effective (p = 0.0035). Based on live worm counts, the efficacy in study no. 2 was 100 % (p = 0.0030). It is concluded that two applications of Profender® spot-on given two weeks apart represent a safe and highly efficacious treatment regime against feline aelurostrongylosis. PMID:26152416

  7. The Accuracy of Praziquantel Dose Poles for Mass Treatment of Schistosomiasis in School Girls in KwaZulu-Natal, South Africa

    PubMed Central

    Baan, Marije; Galappaththi-Arachchige, Hashini Nilushika; Gagai, Silindile; Aurlund, Christine G.; Vennervald, Birgitte J.; Taylor, Myra; van Lieshout, Lisette; Kjetland, Eyrun F.

    2016-01-01

    Background More than 260 million people live with schistosomiasis and regular mass-treatment should be implemented to prevent morbidity. Praziquantel, dosed at 40 milligrams per kilogram bodyweight, is the drug of choice. During the last decades the WHO Tablet Pole–which estimates tablet need by height as representing weight–has been used as a practical and cheap tool in mass treatment. In South Africa this method could be inaccurate given the prevalence of overweight and obesity. In this study in female pupils in KwaZulu-Natal, South Africa, we explored the accuracy of the WHO Tablet Pole and the recently developed Modified Dose Pole for adults with two additional intervals and correction for body mass index (BMI). Methodology In randomly selected primary and secondary schools of schistosomiasis-endemic areas, height and weight of female pupils were measured. The WHO Tablet Pole and Modified Dose Pole were used to indicate the amount of praziquantel according to height and the dose in milligrams per kilogram bodyweight was calculated. The BMI correction was performed by adding 600 milligrams (1 tablet) to the indicated dose if a person was overweight/obese. Principal Findings 3157 female students were investigated and 35% were found to be overweight/obese. Using the WHO Tablet Pole, 73% would have received an adequate dose (range 30–60 mg/kg). When correcting for BMI, this would have been 94%. Using the Modified Dose Pole with BMI correction, 97% would have been adequately treated. Conclusions This study shows that the WHO Tablet Pole will be inaccurate in estimating the dose of praziquantel in South African girls due to high prevalence of overweight/obesity. Under-dosing of individuals who appear overweight/obese could be largely prevented by adding an extra praziquantel tablet to the recommended dose. Further research must be done to explore if subjective weight estimates are reliable. PMID:27139497

  8. Uma Krishnaswami and International Imaginings

    ERIC Educational Resources Information Center

    Aldama, Frederick Luis

    2006-01-01

    This article presents an interview with South Asian children's book and young adult fiction writer, Uma Krishnaswami. The interviewer states that "in all her creative endeavors Uma's keen sense of detail, narrative voice, and characterization complicate and humanize portrayals of multicultural peoples worldwide." In this interview, Krishnaswami…

  9. Effect of repeated targeted mass treatment with praziquantel on the prevalence, intensity of infection and morbidity due to Schistosoma intercalatum in an urban community in equatorial Guinea.

    PubMed

    Simarro, P P; Sima, F O; Mir, M; Ndong, P

    1991-09-01

    A longitudinal community-based study was carried out in order to evaluate the impact of repeated selective population chemotherapy with praziquantel on the epidemiology of an urban focus of Schistosoma intercalatum in the city of Bata, capital of the Continental Region of Equatorial Guinea. Three surveys were undertaken in January of 1988, 1989 and 1990, determining parasitological prevalence, intensity of infection and morbidity and applying repeated targeted mass treatment. One dose of praziquantel (40 mg/kg body weight) was given one week after treatment with mebendazole (100 mg every 12 hours for 3 days). A reduction of the overall prevalence by S. intercalatum of 69.9% and 79.3% in the first and second year respectively was found. Persons showing high parasite burden suffered a reduction of 95.7%. The cure rate (no more eggs in stool) was between 90% and 98.9%. A significant decrease of signs and symptoms was observed. No important side effects were detected. This study shows the positive action of praziquantel in reducing prevalence, intensity of infection and morbidity due to S. intercalatum, above all in the case of a high human population participation response. Cure rates obtained being similar to the ones observed using the same drug in Schistosoma mansoni and Schistosoma haematobium. PMID:1801138

  10. Effect of Maternal Schistosoma mansoni Infection and Praziquantel Treatment During Pregnancy on Schistosoma mansoni Infection and Immune Responsiveness among Offspring at Age Five Years

    PubMed Central

    Tweyongyere, Robert; Naniima, Peter; Mawa, Patrice A.; Jones, Frances M.; Webb, Emily L.; Cose, Stephen; Dunne, David W.; Elliott, Alison M.

    2013-01-01

    Introduction Offspring of Schistosoma mansoni-infected women in schistosomiasis-endemic areas may be sensitised in-utero. This may influence their immune responsiveness to schistosome infection and schistosomiasis-associated morbidity. Effects of praziquantel treatment of S. mansoni during pregnancy on risk of S. mansoni infection among offspring, and on their immune responsiveness when they become exposed to S. mansoni, are unknown. Here we examined effects of praziquantel treatment of S. mansoni during pregnancy on prevalence of S. mansoni and immune responsiveness among offspring at age five years. Methods In a trial in Uganda (ISRCTN32849447, http://www.controlled-trials.com/ISRCTN32849447/elliott), offspring of women treated with praziquantel or placebo during pregnancy were examined for S. mansoni infection and for cytokine and antibody responses to SWA and SEA, as well as for T cell expression of FoxP3, at age five years. Results Of the 1343 children examined, 32 (2.4%) had S. mansoni infection at age five years based on a single stool sample. Infection prevalence did not differ between children of treated or untreated mothers. Cytokine (IFNγ, IL-5, IL-10 and IL-13) and antibody (IgG1, Ig4 and IgE) responses to SWA and SEA, and FoxP3 expression, were higher among infected than uninfected children. Praziquantel treatment of S. mansoni during pregnancy had no effect on immune responses, with the exception of IL-10 responses to SWA, which was higher in offspring of women that received praziquantel during pregnancy than those who did not. Conclusion We found no evidence that maternal S. mansoni infection and its treatment during pregnancy influence prevalence and intensity of S. mansoni infection or effector immune response to S. mansoni infection among offspring at age five years, but the observed effects on IL-10 responses to SWA suggest that maternal S. mansoni and its treatment during pregnancy may affect immunoregulatory responsiveness in childhood

  11. Safety and efficacy of praziquantel syrup (Epiquantel®) against Schistosoma haematobium and Schistosoma mansoni in preschool-aged children in Niger.

    PubMed

    Garba, Amadou; Lamine, Mariama S; Djibo, Ali; Tahirou, Almoustapha; Aouami, Mahamadou Aboubacar; Alfari, Aichatou; Phillips, Anna E; Fenwick, Alan; Utzinger, Jürg

    2013-11-01

    Given the characteristic age-prevalence curve of Schistosoma infection, preventive chemotherapy with praziquantel is primarily targeted at school-aged children, whilst, in highly endemic areas, other high-risk groups might be included for regular treatment. Nevertheless, schistosomiasis can affect children well before they reach school-age, but this population group is usually excluded from preventive chemotherapy. We assessed the safety and efficacy of praziquantel syrup (Epiquantel®) in preschool-aged children in three villages of Niger. Children aged ≤72 months provided multiple urine and stool samples that were microscopically examined using standard protocols. Schistosoma-positive children were treated with praziquantel syrup at a dose of 40 mg/kg after a meal of millet porridge. Children remained under medical supervision for 4h and adverse events were recorded. Additionally, a questionnaire was administrated to the mothers/guardians 24h post-treatment for further probing of adverse events. Treatment efficacy was evaluated 3 and 6 weeks post-treatment using multiple stool and urine samples. A third of the 243 treated children reported adverse events within 4h, whilst a further 6.2% reported adverse events upon probing 24h post-treatment. Abdominal pain, bloody diarrhoea and sleepiness were the most common adverse events, but these were transient and self-limiting. Praziquantel syrup showed moderate-to-high efficacy against Schistosoma haematobium with egg reduction rates of 69.4% and 71.2% 3 and 6 weeks post-treatment and cure rates of 85.7% (95% confidence interval (CI) 79.7-90.5%) and 94.9% (95% CI 90.5-97.6%), respectively. Considerably lower cure and egg reduction rates were observed against Schistosoma mansoni (e.g. cure rate at 6-week post-treatment follow-up was only 50.6% (95% CI 39.9-61.2%). Concluding, praziquantel syrup is well tolerated in preschool-aged children with moderate-to-high efficacy against S. haematobium, but considerably lower

  12. The Universe in a Box: Introduction to the Study of Astronomy in the Initial Formation of Physics Teachers. (Spanish Title: El Universo Representado en Una Caja: Introducción al Estudio de la Astronomía en la Formación Inicial de Profesores de Física.) O Universo Representado em Uma Caixa: Introdução ao Estudo da Astronomia NA Formação Inicial de Professores de Física

    NASA Astrophysics Data System (ADS)

    Longhini, Marcos Daniel

    2009-07-01

    This is a report of an activity of introduction to the study of Astronomy developed with a group of future Physics teachers at a Brazilian public university. Such activity had the goal of giving privileged emphasis to notions of spatiality, alternative conceptions of the participants and the process of interaction among peers, and consisted of the representation, in a three dimensional space, of the models of the universe that the participants had. The results, which were categorized as miscellaneous, geocentric, heliocentric and acentric models of the universe, were qualitatively analyzed. Analyses of the activity in the perspective of the participants are indicated and additional considerations are made regarding its use as a resource for teaching Astronomy and for teacher training. Este es el informe de una actividad para presentar un estudio introductorio de la Astronomía, desarrollado con una clase de futuros profesores de física en una universidad pública brasileña. Esta actividad tuvo como objetivo centrar las nociones de espacialidad, las concepciones alternativas de los participantes y el proceso de interacción entre pares, y consistió en la representación en un espacio tridimensional, de los modelos del universo que los participantes habían. Los resultados, que se clasificaron en universo miscelania, geocéntrico, heliocéntrico y acentrico, se analizaron cualitativamente. Son identificadas análisis de la actividad por los participantes, e hizo observaciones sobre su uso como recurso para la enseñanza de la astronomía y la formación de docentes. Trata-se do relato de uma atividade de introdução ao estudo da Astronomia, desenvolvida com uma turma de futuros professores de Física, em uma universidade pública brasileira. Tal atividade teve como meta privilegiar noções de espacialidade, as concepções alternativas dos participantes e o processo de interação entre pares e constou da representação, em um espaço tridimensional, dos

  13. Improvement of the in vitro dissolution of praziquantel by complexation with alpha-, beta- and gamma-cyclodextrins.

    PubMed

    Becket, G; Schep, L J; Tan, M Y

    1999-03-01

    Although praziquantel (PZQ) is the primary drug of choice in the treatment of schistosomiasis, its poor solubility has restricted its delivery via the oral route. In spite of its poor solubility, PZQ is well absorbed across the gastrointestinal tract, but large doses are required to achieve adequate concentrations at the target sites. Improving the solubility would enable the parenteral route to be used, thereby avoiding significant first pass metabolism. The aqueous solubility of PZQ was improved by forming inclusion complexes with alpha-, beta- and gamma-cyclodextrins (CDs). These complexes were assessed and confirmed by solubility analysis, Fourier transform infrared analysis, elemental analysis, differential scanning calorimetry and mass spectrometry. Dissolution of PZQ from the alpha-, beta- and gamma-CD complexes was 2.6-, 5- and 8-fold greater, respectively, than that of the pure drug. However, only the beta-complex had a stability constant in the optimum range for pharmaceutical use, suggesting that the preferred complex for further development would be a water-soluble beta-CD derivative. PMID:10053203

  14. Preclinical pharmacokinetic evaluation of praziquantel loaded in poly (methyl methacrylate) nanoparticle using a HPLC-MS/MS.

    PubMed

    Malhado, Mayara; Pinto, Douglas P; Silva, Aline C A; Silveira, Gabriel P E; Pereira, Heliana M; Santos, Jorge G F; Guilarducci-Ferraz, Carla V V; Viçosa, Alessandra L; Nele, Márcio; Fonseca, Laís B; Pinto, José Carlos C S; Calil-Elias, Sabrina

    2016-01-01

    Praziquantel (PZQ) is the drug recommended by the World Health Organization for treatment of schistosomiasis. However, the treatment of children with PZQ tablets is complicated due to difficulties to adapt the dose and the extremely bitter taste of PZQ. For this reason, poly (methyl methacrylate) nanoparticles loaded with Praziquantel (PZQ-NP) were developed for preparation of a new formulation to be used in the suspension form. For this reason, the main aim of the present study was to evaluate the pharmacokinetic (PK) profile of PZQ-NP, through HPLC-MS/MS assays. Analyses were performed with an Omnisphere C18 column (5.0 μm×4.6 mm×150.0 mm), using a mixture of an aqueous solution containing 0.1 wt% of formic acid and methanol (15:85-v/v) as the mobile phase at a flow rate of 0.800mL/min. Detection was performed with a hybrid linear ion-trap triple quadrupole mass spectrometer with multiple reactions monitoring in positive ion mode via electrospray ionization. The monitored transitions were m/z 313.18>203.10 for PZQ and m/z 285.31>193.00 for the Internal Standard. The method was validated with the quantification limit of 1.00 ng/mL, requiring samples of 25 μL for analyses. Analytic responses were calibrated with known concentration data, leading to correlation coefficients (r) higher than 0.99. Validation performed with rat plasma showed that PZQ was stable for at least 10 months when stored below -70 °C (long-term stability), for at least 17 h when stored at room temperature (RT, 22 °C) (short-term stability), for at least 47 h when stored at room temperature in auto-sampler vials (post-preparative stability) and for at least 8 successive freeze/thaw cycles at -70 °C. For PK assays, Wistar rats, weighing between 200 and 300 g were used. Blood samples were collected from 0 to 24 h after oral administration of single doses of 60 mg/kg of PZQ-NP or raw PZQ (for the control group). PZQ was extracted from plasma by liquid-liquid extraction with terc-butyl methyl

  15. Development of flexible and dispersible oral formulations containing praziquantel for potential schistosomiasis treatment of pre-school age children.

    PubMed

    Trastullo, Ramona; Dolci, Luisa Stella; Passerini, Nadia; Albertini, Beatrice

    2015-11-10

    Praziquantel (PZQ), an anthelmintic drug used in developing countries for the treatment of schistosome infections, was processed using the fluid bed wet granulation technology to prepare fast dispersible granules, as an appropriate and flexible dosage form for pre-school-aged children. Granulation experiments were performed incorporating PZQ either in the powder mixture, according to the traditional way, or in the liquid phase containing wetting agents. In the powder mixture several excipients were tested: Flowlac 100 as filler, Galeniq 721 (isomalt) and Neosorb P 100 T (D-sorbitol) as sweeteners and PVP K30 as binder; while in the liquid phase Lutrol F68, Cremophor RH 40 or Tween 80 as surfactants were investigated. Different formulations loaded with 10% w/w (batches 1-8) and 20% w/w of PZQ (batches 9-13) were produced The majority of granules displayed good flow properties and uniform drug content. X-ray powder diffraction showed that PZQ remained in its original crystalline state, while differential scanning calorimetry and Fourier transform-infrared analysis evidenced the formation of chemical interactions among the ingredients. The solubilisation test performed in non-sink condition to reproduce the actual condition in which a child of 4 years takes the medicine revealed that granules quickly formed a very fine suspension in water (dV90=39.9 μm). Although after the granulation process the solubility of raw PZQ was not increased, adding the aqueous suspension to 500 ml of buffer solution of pH 1.5, simulating the fasted state of a child, 50% of the drug was dissolved after 30 min. After granule manipulation with milk and fruit juices, no PZQ degradation was observed during time. Finally, the selected granule formulation provided evidence to be stable even at hot and very humid climate (30°C/75% RH), at least for the examined time. PMID:26386139

  16. Morphological Characteristics of Schistosoma mansoni PZQ-Resistant and -Susceptible Strains Are Different in Presence of Praziquantel

    PubMed Central

    Pinto-Almeida, António; Mendes, Tiago; de Oliveira, Rosimeire Nunes; Corrêa, Sheila de Andrade Penteado; Allegretti, Silmara Marques; Belo, Silvana; Tomás, Ana; Anibal, Fernanda de Freitas; Carrilho, Emanuel; Afonso, Ana

    2016-01-01

    Schistosomiasis is one of the most common human parasitic diseases whose socioeconomic impact is only surpassed by malaria. Praziquantel (PZQ) is the only drug commercially available for the treatment of all schistosome species causing disease in humans. However, there has been stronger evidences of PZQ-resistance on Schistosoma mansoni and thus it is very important to study the phenotypic characteristics associated with it. The aim of this study was to evaluate morphological alterations in S. mansoni PZQ-resistant adult worms and eggs, by comparing a PZQ- resistant strain obtained under PZQ drug pressure with a PZQ-susceptible strain. For this, scanning electronic microscopy was used to assess tegumental responsiveness of both strains under PZQ exposure, and optical microscopy allowed the monitoring of worms and eggs in the presence of the drug. Those assays showed that PZQ-susceptible worms exposed to the drug had more severe tegumental damages than the resistant one, which had only minor alterations. Moreover, contrary to what occurred in the susceptible strain, resistant worms were viable after PZQ exposure and gradually regaining full motility after removal of the drug. Eggs from resistant strain parasites are considerably smaller than those from susceptible strain. Our results suggest that there might be a difference in the tegument composition of the resistant strain and that worms are less responsive to PZQ. Changes observed in egg morphology might imply alterations in the biology of schistosomes associated to PZQ-resistance, which could impact on transmission and pathology of the disease. Moreover, we propose a hypothetical scenario where there is a different egg tropism of the S. mansoni resistant strain. This study is the first comparing two strains that only differ in their resistance characteristics, which makes it a relevant step in the search for resistance determinants. PMID:27199925

  17. Anthelmintic efficacies of a tablet formula of ivermectin-praziquantel on horses experimentally infected with three Strongylus species.

    PubMed

    Bonneau, Stephane; Maynard, Laurence; Tomczuk, Krzysztof; Kok, Dawid; Eun, Hyone-Myong

    2009-09-01

    In this blinded randomized and controlled study, the anthelmintic efficacy of a tablet formula of ivermectin-praziquantel was evaluated in horses experimentally infected with three species of Strongylus larvae. Eighteen previously dewormed horses were inoculated on study day 0 with third-stage larvae of Strongylus vulgaris, Strongylus equinus, and Strongylus edentatus. The horses were randomly allocated to three groups (n = 6): test-drug (tablet formula), positive-control (reference gel), and negative-control (placebo tablet). On day 56, the horses were treated once with the respective drugs. On day 95, the horses were sacrificed, and necropsy examinations were performed to assess the status of the parasite burden (L4 and immature L5) and pathological lesions on selected organs and tissues. By the criteria of worm counts, the test-drug and positive-control showed, respectively, 100% and 97.3% anthelmintic efficacies on S. vulgaris, 100% and 81.4% on S. equinus, and equally 100% on S. edentatus. However, the efficacies on S. equinus and S. edentatus should be taken only as face values considering their respective low worm counts in the placebo group. The S. vulgaris-induced arterial lesions were also reduced in the test-drug and positive-control groups with efficacies of 73.9% and 62.9%, respectively. No adverse reactions were observed with either of the drugs. Our data demonstrate that the Equimax tablet formula was as safe and efficacious as the gel formula anthelmintic on large strongyles in horses. PMID:19488785

  18. Chemometric quality inspection control of pyrantel pamoate, febantel and praziquantel in veterinary tablets by mid infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Piantavini, Mário S.; Pontes, Flávia L. D.; Uber, Caroline P.; Stremel, Dile P.; Sena, Marcelo M.; Pontarolo, Roberto

    This paper describes the development and validation of a new multivariate calibration method based on diffuse reflectance mid infrared spectroscopy for direct and simultaneous determination of three veterinary pharmaceutical drugs, pyrantel pamoate, praziquantel and febantel, in commercial tablets. The best synergy interval partial least squares (siPLS) model was obtained by selecting three spectral regions, 3715-3150, 2865-2583, and 2298-1733 cm-1, preprocessed by first derivative and Savitzky-Golay smoothing followed by mean centering. This model was built with five latent variables and provided root mean square errors of prediction (RMSEP) equal or lower than 0.69 mg per 100 mg of powder for the three analytes. The method was validated according the appropriate regulations through the estimate of figures of merit, such as trueness, precision, linearity, analytical sensitivity, bias and residual prediction deviation (RPD). Then, it was applied to three different veterinary pharmaceutical formulations found in the Brazilian market, in a situation of multi-product calibration, since the excipient composition of these commercial products, which was not known a priori, was modeled by an experimental design that scanned the likely content range of the possible constituents. The results were verified with high performance liquid chromatography with diode array detection (HPLC-DAD) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and were in agreement with the predicted values at 95% confidence level. The developed method presented the advantages of being simple, rapid, solvent free, and about ten times faster than the HPLC ones.

  19. Chemometric quality inspection control of pyrantel pamoate, febantel and praziquantel in veterinary tablets by mid infrared spectroscopy.

    PubMed

    Piantavini, Mário S; Pontes, Flávia L D; Uber, Caroline P; Stremel, Dile P; Sena, Marcelo M; Pontarolo, Roberto

    2014-05-01

    This paper describes the development and validation of a new multivariate calibration method based on diffuse reflectance mid infrared spectroscopy for direct and simultaneous determination of three veterinary pharmaceutical drugs, pyrantel pamoate, praziquantel and febantel, in commercial tablets. The best synergy interval partial least squares (siPLS) model was obtained by selecting three spectral regions, 3715-3150, 2865-2583, and 2298-1733 cm(-1), preprocessed by first derivative and Savitzky-Golay smoothing followed by mean centering. This model was built with five latent variables and provided root mean square errors of prediction (RMSEP) equal or lower than 0.69 mg per 100 mg of powder for the three analytes. The method was validated according the appropriate regulations through the estimate of figures of merit, such as trueness, precision, linearity, analytical sensitivity, bias and residual prediction deviation (RPD). Then, it was applied to three different veterinary pharmaceutical formulations found in the Brazilian market, in a situation of multi-product calibration, since the excipient composition of these commercial products, which was not known a priori, was modeled by an experimental design that scanned the likely content range of the possible constituents. The results were verified with high performance liquid chromatography with diode array detection (HPLC-DAD) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and were in agreement with the predicted values at 95% confidence level. The developed method presented the advantages of being simple, rapid, solvent free, and about ten times faster than the HPLC ones. PMID:24566119

  20. Morphological Characteristics of Schistosoma mansoni PZQ-Resistant and -Susceptible Strains Are Different in Presence of Praziquantel.

    PubMed

    Pinto-Almeida, António; Mendes, Tiago; de Oliveira, Rosimeire Nunes; Corrêa, Sheila de Andrade Penteado; Allegretti, Silmara Marques; Belo, Silvana; Tomás, Ana; Anibal, Fernanda de Freitas; Carrilho, Emanuel; Afonso, Ana

    2016-01-01

    Schistosomiasis is one of the most common human parasitic diseases whose socioeconomic impact is only surpassed by malaria. Praziquantel (PZQ) is the only drug commercially available for the treatment of all schistosome species causing disease in humans. However, there has been stronger evidences of PZQ-resistance on Schistosoma mansoni and thus it is very important to study the phenotypic characteristics associated with it. The aim of this study was to evaluate morphological alterations in S. mansoni PZQ-resistant adult worms and eggs, by comparing a PZQ- resistant strain obtained under PZQ drug pressure with a PZQ-susceptible strain. For this, scanning electronic microscopy was used to assess tegumental responsiveness of both strains under PZQ exposure, and optical microscopy allowed the monitoring of worms and eggs in the presence of the drug. Those assays showed that PZQ-susceptible worms exposed to the drug had more severe tegumental damages than the resistant one, which had only minor alterations. Moreover, contrary to what occurred in the susceptible strain, resistant worms were viable after PZQ exposure and gradually regaining full motility after removal of the drug. Eggs from resistant strain parasites are considerably smaller than those from susceptible strain. Our results suggest that there might be a difference in the tegument composition of the resistant strain and that worms are less responsive to PZQ. Changes observed in egg morphology might imply alterations in the biology of schistosomes associated to PZQ-resistance, which could impact on transmission and pathology of the disease. Moreover, we propose a hypothetical scenario where there is a different egg tropism of the S. mansoni resistant strain. This study is the first comparing two strains that only differ in their resistance characteristics, which makes it a relevant step in the search for resistance determinants. PMID:27199925

  1. Inflammation Caused by Praziquantel Treatment Depends on the Location of the Taenia solium Cysticercus in Porcine Neurocysticercosis

    PubMed Central

    Cangalaya, Carla; Zimic, Mirko; Marzal, Miguel; González, Armando E.; Guerra-Giraldez, Cristina; Mahanty, Siddhartha; Nash, Theodore E.; García, Hector H.

    2015-01-01

    Background Neurocysticercosis (NCC), infection of the central nervous system by Taenia solium cysticerci, is a pleomorphic disease. Inflammation around cysticerci is the major cause of disease but is variably present. One factor modulating the inflammatory responses may be the location and characteristics of the brain tissue adjacent to cysticerci. We analyzed and compared the inflammatory responses to cysticerci located in the parenchyma to those in the meninges or cysticerci partially in contact with both the parenchyma and the meninges (corticomeningeal). Methodology/Principal Findings Histological specimens of brain cysticerci (n = 196) from 11 pigs naturally infected with Taenia solium cysticerci were used. Four pigs were sacrificed after 2 days and four after 5 days of a single dose of praziquantel; 3 pigs did not receive treatment. All pigs were intravenously injected with Evans Blue to assess disruption of the blood-brain barrier. The degree of inflammation was estimated by use of a histological score (ISC) based on the extent of the inflammation in the pericystic areas as assessed in an image composed of several photomicrographs taken at 40X amplification. Parenchymal cysticerci provoked a significantly greater level of pericystic inflammation (higher ISC) after antiparasitic treatment compared to meningeal and corticomeningeal cysticerci. ISC of meningeal cysticerci was not significantly affected by treatment. In corticomeningeal cysticerci, the increase in ISC score was correlated to the extent of the cysticercus adjacent to the brain parenchyma. Disruption of the blood-brain barrier was associated with treatment only in parenchymal tissue. Significance Inflammatory response to cysticerci located in the meninges was significantly decreased compared to parenchymal cysticerci. The suboptimal inflammatory response to cysticidal drugs may be the reason subarachnoid NCC is generally refractory to treatment compared to parenchymal NCC. PMID:26658257

  2. Regular treatments of praziquantel do not impact on the genetic make-up of Schistosoma mansoni in Northern Senegal.

    PubMed

    Huyse, T; Van den Broeck, F; Jombart, T; Webster, B L; Diaw, O; Volckaert, F A M; Balloux, F; Rollinson, D; Polman, K

    2013-08-01

    The Senegal River Basin (SRB) experienced a major epidemic of intestinal schistosomiasis in the early nineties, after the construction of a dam for irrigation purposes. Exceptionally low cure rates following praziquantel (PZQ) treatment at the onset of the epidemic raised concerns about PZQ resistant strains of Schistosoma mansoni, although they could also be attributed to the intense transmission at that time. A field study in the same region more than 15 years later found cure rates for S. mansoni still to be low, whereas Schistosomahaematobium responded well to treatment. We collected S. mansoni miracidia from children at base-line prior to treatment, six months after two PZQ treatments and two years after the start of the study when they had received a total of five PZQ treatments. In total, 434 miracidia from 12 children were successfully genotyped with at least six out of nine DNA microsatellite loci. We found no significant differences in the genetic diversity of, and genetic differentiation between parasite populations before and after repeated treatment, suggesting that PZQ treatment does not have an impact on the neutral evolution of the parasite. This is in stark contrast with a similar study in Tanzania where a significant decrease in genetic diversity was observed in S. mansoni miracidia after a single round of PZQ treatment. We argue that PZQ resistance might play a role in our study area, although rapid re-infection cannot be excluded. It is important to monitor this situation carefully and conduct larger field studies with short-term follow-up after treatment. Since PZQ is the only general schistosomicide available, the possibility of PZQ resistance is of great concern both for disease control and for curative use in clinical practice. PMID:23684792

  3. Population Pharmacokinetics and Pharmacodynamics of Praziquantel in Ugandan Children with Intestinal Schistosomiasis: Higher Dosages Are Required for Maximal Efficacy

    PubMed Central

    Waterhouse, David; de Sousa-Figueiredo, Jose C.; Roberts, Stephen A.; Atuhaire, Aaron; Van Dam, Govert J.; Corstjens, Paul L. A. M.; Scott, Janet T.; Stanton, Michelle C.; Kabatereine, Narcis B.; Ward, Stephen; Hope, William W.; Stothard, J. Russell

    2016-01-01

    ABSTRACT Each year, millions of African children receive praziquantel (PZQ) by mass drug administration (MDA) to treat schistosomiasis at a standard single dose of 40 mg/kg of body weight, a direct extrapolation from studies of adults. A higher dose of 60 mg/kg is also acceptable for refractory cases. We conducted the first PZQ pharmacokinetic (PK) and pharmacodynamic (PD) study in young children comparing dosing. Sixty Ugandan children aged 3 to 8 years old with egg patent Schistosoma mansoni received PZQ at either 40 mg/kg or 60 mg/kg. PK parameters of PZQ racemate and enantiomers (R and S) were quantified. PD outcomes were assessed by standard fecal egg counts and novel schistosome-specific serum (circulating anodic antigen [CAA]) and urine (circulating cathodic antigen [CCA]) antigen assays. Population PK and PD analyses were performed to estimate drug exposure in individual children, and the relationship between drug exposure and parasitological cure was estimated using logistic regression. Monte Carlo simulations were performed to identify better, future dosing regimens. There was marked PK variability between children, but the area under the concentration-time curve (AUC) of PZQ was strongly predictive of the parasitological cure rate (CR). Although no child achieved antigenic cure, which is suggestive of an important residual adult worm burden, higher AUC was associated with greater CAA antigenic decline at 24 days. To optimize the performance of PZQ, analysis of our simulations suggest that higher doses (>60 mg/kg) are needed, particularly in smaller children. PMID:27507822

  4. Effectiveness of hyperbaric oxygen for experimental treatment of schistosomiasis mansoni using praziquantel-free and encapsulated into liposomes: assay in adult worms and oviposition.

    PubMed

    Frezza, Tarsila Ferraz; de Souza, Ana Luiza Ribeiro; Prado, César Corat Ribeiro; de Oliveira, Claudineide Nascimento Fernandes; Gremião, Maria Palmira Daflon; Giorgio, Selma; Dolder, Mary Anne Heidi; Joazeiro, Paulo Pinto; Allegretti, Silmara Marques

    2015-10-01

    The treatment of schistosomiasis depends on a single drug: praziquantel (PZQ). However, this treatment presents limitations such as low and/or erratic bioavailability that can contribute to cases of tolerance. Improvements to the available drug are urgently needed and studies with a controlled system of drug release, like liposomes, have been gaining prominence. The present study evaluated the activity and synergy between liposomal-praziquantel (lip.PZQ) and hyperbaric oxygen therapy (HBO). Mice received doses of 60 or 100mg/kg PZQ or lip.PZQ, 50 days post-infection, and after the treatment, were exposed to HBO (3 atmosphere absolute - ATA) for 1h. The viability of adult worms and oviposition were analyzed, by necropsy and Kato-Katz examination performed after 15 days of treatment. A concentration of 100mg/kg of lip.PZQ+HBO was more effective (48.0% reduction of worms, 83.3% reduction of eggs/gram of feces) and 100% of the mice had altered of oograms (indicating interruption of oviposition) compared to other treatments and to the Control group (infected and untreated). It is known that PZQ requires participation of the host immune system to complete its antischistosomal activity and that HBO is able to stimulate the immune system. The drug became more available in the body when incorporated into liposomes and, used with HBO, the HBO worked as an adjuvant. This explains the decreases of oviposition and worms recovered form hepatic portal system. PMID:26215128

  5. Human IgG1 Responses to Surface Localised Schistosoma mansoni Ly6 Family Members Drop following Praziquantel Treatment

    PubMed Central

    Chalmers, Iain W.; Fitzsimmons, Colin M.; Brown, Martha; Pierrot, Christine; Jones, Frances M.; Wawrzyniak, Jakub M.; Fernandez-Fuentes, Narcis; Tukahebwa, Edridah M.; Dunne, David W.; Khalife, Jamal; Hoffmann, Karl F.

    2015-01-01

    Background The heptalaminate-covered, syncytial tegument is an important anatomical adaptation that enables schistosome parasites to maintain long-term, intravascular residence in definitive hosts. Investigation of the proteins present in this surface layer and the immune responses elicited by them during infection is crucial to our understanding of host/parasite interactions. Recent studies have revealed a number of novel tegumental surface proteins including three (SmCD59a, SmCD59b and Sm29) containing uPAR/Ly6 domains (renamed SmLy6A SmLy6B and SmLy6D in this study). While vaccination with SmLy6A (SmCD59a) and SmLy6D (Sm29) induces protective immunity in experimental models, human immunoglobulin responses to representative SmLy6 family members have yet to be thoroughly explored. Methodology/Principal Findings Using a PSI-BLAST-based search, we present a comprehensive reanalysis of the Schistosoma mansoni Ly6 family (SmLy6A-K). Our examination extends the number of members to eleven (including three novel proteins) and provides strong evidence that the previously identified vaccine candidate Sm29 (renamed SmLy6D) is a unique double uPAR/Ly6 domain-containing representative. Presence of canonical cysteine residues, signal peptides and GPI-anchor sites strongly suggest that all SmLy6 proteins are cell surface-bound. To provide evidence that SmLy6 members are immunogenic in human populations, we report IgG1 (as well as IgG4 and IgE) responses against two surface-bound representatives (SmLy6A and SmLy6B) within a cohort of S. mansoni-infected Ugandan males before and after praziquantel treatment. While pre-treatment IgG1 prevalence for SmLy6A and SmLy6B differs amongst the studied population (7.4% and 25.3% of the cohort, respectively), these values are both higher than IgG1 prevalence (2.7%) for a sub-surface tegumental antigen, SmTAL1. Further, post-treatment IgG1 levels against surface-associated SmLy6A and SmLy6B significantly drop (p = 0.020 and p < 0

  6. Cosmoeducação: uma proposta para o ensino de astronomia

    NASA Astrophysics Data System (ADS)

    Medeiros, L. A. L.; Jafelice, L. C.

    2003-08-01

    Entende-se por cosmoeducação o desenvolvimento vivencial da unidade homem-cosmo. Este conceito é norteado pela psicologia transpessoal, que estuda o ser humano em sua totalidade, onde suas relações ecológicas e cósmicas são de grande importância. Constata-se uma necessidade latente no ser humano moderno em resgatar uma relação holística com o Universo. Neste trabalho exploramos meios de cultivar a consciência de que o ser humano constitui parte integrante do cosmo e se relaciona com este com o objetivo de promover em si uma percepção ambiental mais ampla. Nossa hipótese de trabalho inicial foi que o ensino de conteúdos básicos em astronomia realizado através de uma abordagem holística, que incorpore práticas vivenciais correlacionadas àqueles conteúdos, pode despertar no indivíduo sua identidade cósmica. O método que utilizamos é o fenomenológico e o universo desta pesquisa é um grupo de estudantes da disciplina de Astronomia (Curso de Licenciatura em Geografia/UFRN), onde realizamos observação participante, entrevistas, depoimentos e as práticas vivenciais mencionadas. Neste caso estamos desenvolvendo e adaptando exercícios de algumas técnicas terapêuticas de psicologia transpessoal, que um de nós (LALM) tem aplicado no contexto clínico, para trabalhar aspectos cognitivos envolvidos naquele processo de conscientização cósmica. Resultados parciais claramente referendam a hipótese inicial. Um resultado a destacar é fruto de uma dinâmica de representação corporal interiorizada do eclipse lunar, envolvendo um pequeno grupo daqueles estudantes, na qual conteúdos míticos afloraram de maneira espontânea e contundente para todos, sugerindo ressonância, ou pelo menos isomorfismo, entre o macro e o microcosmo. Este e outros resultados são discutidos em detalhe neste trabalho. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP).

  7. A DFT study of infrared spectra and Monte Carlo predictions of the solvation shell of Praziquantel and β-cyclodextrin inclusion complex in liquid water.

    PubMed

    de Oliveira, C X; Ferreira, N S; Mota, G V S

    2016-01-15

    In this paper, we report a theoretical study of the inclusion complexes of Praziquantel (PZQ) and β-cyclodextrin (β-CD) in liquid water. The starting geometry has been carried out by molecular mechanics simulations, and afterwards optimized in B3LYP level with a 6-311G(d) basis set. Monte Carlo simulations have been used to calculate the solvation shell of the PZQ/β-CD inclusion complexes. Moreover, the vibrational frequencies and the infrared intensities for the PZQ/β-CD complex were computed using the B3LYP method. It is demonstrated that this combined model can yield well-converged thermodynamic data even for a modest number of sample configurations, which makes the methodology particularly adequate for understanding the solute-solvent interaction used for generating the liquid structures of one solute surrounded by solvent molecules. The complex solvation shell showed an increase of the water molecule level in relation to the isolated PZQ molecule because of the hydrophilic effect of the CD molecule. The infrared spectra showed that the contribution that originated in the PZQ molecule was not predominant in the upper-wave number region in the drug/β-CD. The movement that purely originated in the PZQ molecule was localized in the absorption band, ranging from 1328 to 1688cm(-1). PMID:26296254

  8. Wharton’s jelly-derived mesenchymal stem cells combined with praziquantel as a potential therapy for Schistosoma mansoni-induced liver fibrosis

    PubMed Central

    Hammam, Olfat A.; Elkhafif, Nagwa; Attia, Yasmeen M.; Mansour, Mohamed T.; Elmazar, Mohamed M.; Abdelsalam, Rania M.; Kenawy, Sanaa A.; El-Khatib, Aiman S.

    2016-01-01

    Liver fibrosis is one of the most serious consequences of S. mansoni infection. The aim of the present study was to investigate the potential anti-fibrotic effect of human Wharton’s jelly-derived mesenchymal stem cells (WJMSCs) combined with praziquantel (PZQ) in S. mansoni-infected mice. S. mansoni-infected mice received early (8th week post infection) and late (16th week post infection) treatment with WJMSCs, alone and combined with oral PZQ. At the 10th month post infection, livers were collected for subsequent flow cytometric, histopathological, morphometric, immunohistochemical, gene expression, and gelatin zymographic studies. After transplantation, WJMSCs differentiated into functioning liver-like cells as evidenced by their ability to express human hepatocyte-specific markers. Regression of S. mansoni-induced liver fibrosis was also observed in transplanted groups, as evidenced by histopathological, morphometric, and gelatin zymographic results besides decreased expression of three essential contributors to liver fibrosis in this particular model; alpha smooth muscle actin, collagen-I, and interleukin-13. PZQ additionally enhanced the beneficial effects observed in WJMSCs-treated groups. Our results suggest that combining WJMSCs to PZQ caused better enhancement in S. mansoni-induced liver fibrosis, compared to using each alone. PMID:26876222

  9. Efficacy of a topical combination of fipronil, (S)-methoprene, eprinomectin and praziquantel (Broadline(®)) against naturally acquired infections with cestodes of the genus Joyeuxiella in cats.

    PubMed

    Schuster, Rolf K; Mustafa, Murad Basheer; Baskar, Jagadeesan Vijay; Rosentel, Joseph; Chester, S Theodore; Knaus, Martin

    2016-07-01

    Cats are host to dipylidiid cestodes of the genera Diplopylidium, Dipylidium and Joyeuxiella. Broadline(®), a topical broad-spectrum combination parasiticide containing fipronil (8.3 % w/v), (S)-methoprene (10 % w/v), eprinomectin (0.4 % w/v) and the cestocide praziquantel (8.3 % w/v), has previously been shown to be efficacious against Dipylidium caninum and Diplopylidium spp. in cats. To evaluate its efficacy against Joyeuxiella species, a blinded clinical efficacy study was conducted according to GCP. All cats had evidence for naturally acquired dipylidiid cestode infection as confirmed by pre-treatment examination. Cats were allocated randomly to two groups of 13 cats each based on bodyweight: Control (untreated) and Broadline(®) at 0.12 mL/kg bodyweight administered once topically. Based on the comparison of helminth counts in the treated and untreated cats seven days post treatment, Broadline(®) demonstrated >99 % efficacy (p < 0.01) against mature J. fuhrmanni and J. pasqualei, with 11 and 13 of the untreated cats harbouring 1 to 102 or 2 to 95 cestodes, respectively. In addition, parasite counts indicated 95.9 % efficacy (p = 0.006) against the rictularoid nematode Pterygodermatites cahirensis. PMID:27026504

  10. Simultaneous determination of praziquantel, pyrantel embonate, febantel and its active metabolites, oxfendazole and fenbendazole, in dog plasma by liquid chromatography/mass spectrometry.

    PubMed

    Klausz, Gabriella; Keller, Éva; Sára, Zoltán; Székely-Körmöczy, Péter; Laczay, Péter; Ary, Kornélia; Sótonyi, Péter; Róna, Kálmán

    2015-12-01

    A liquid chromatography-electrospray-mass spectrometry method (LC/MS) has been developed and validated for determination of praziquantel (PZQ), pyrantel (PYR), febantel (FBT), and the active metabolites fenbendazole (FEN) and oxfendazole (OXF), in dog plasma, using mebendazole as internal standard (IS). The method consists of solid-phase extractions on Strata-X polymeric cartridges. Chromatographic separation was carried out on a Phenomenex Gemini C6 -Phenyl column using binary gradient elution containing methanol and 50 mm ammonium-formate (pH 3). The method was linear (r(2)  ≥ 0.990) over concentration ranges of 3-250 ng/mL for PYR andFEB, 5-250 ng/mL for OXF and FEN, and 24-1000 ng/mL for PZQ. The mean precisions were 1.3-10.6% (within-run) and 2.5-9.1% (between-run), and mean accuracies were 90.7-109.4% (within-run) and 91.6-108.2% (between-run). The relative standard deviations (RSD) were <9.1%. The mean recoveries of five targeted compounds from dog plasma ranged from 77 to 94%.The new LC/MS method described herein was fully validated and successfully applied to the bioequivalence studies of different anthelmintic formulations such as tablets containing PZQ, PYR embonate and FBT in dogs after oral administration. PMID:26104502

  11. A DFT study of infrared spectra and Monte Carlo predictions of the solvation shell of Praziquantel and β-cyclodextrin inclusion complex in liquid water

    NASA Astrophysics Data System (ADS)

    de Oliveira, C. X.; Ferreira, N. S.; Mota, G. V. S.

    2016-01-01

    In this paper, we report a theoretical study of the inclusion complexes of Praziquantel (PZQ) and β-cyclodextrin (β-CD) in liquid water. The starting geometry has been carried out by molecular mechanics simulations, and afterwards optimized in B3LYP level with a 6-311G(d) basis set. Monte Carlo simulations have been used to calculate the solvation shell of the PZQ/β-CD inclusion complexes. Moreover, the vibrational frequencies and the infrared intensities for the PZQ/β-CD complex were computed using the B3LYP method. It is demonstrated that this combined model can yield well-converged thermodynamic data even for a modest number of sample configurations, which makes the methodology particularly adequate for understanding the solute-solvent interaction used for generating the liquid structures of one solute surrounded by solvent molecules. The complex solvation shell showed an increase of the water molecule level in relation to the isolated PZQ molecule because of the hydrophilic effect of the CD molecule. The infrared spectra showed that the contribution that originated in the PZQ molecule was not predominant in the upper-wave number region in the drug/β-CD. The movement that purely originated in the PZQ molecule was localized in the absorption band, ranging from 1328 to 1688 cm- 1.

  12. Wharton's jelly-derived mesenchymal stem cells combined with praziquantel as a potential therapy for Schistosoma mansoni-induced liver fibrosis.

    PubMed

    Hammam, Olfat A; Elkhafif, Nagwa; Attia, Yasmeen M; Mansour, Mohamed T; Elmazar, Mohamed M; Abdelsalam, Rania M; Kenawy, Sanaa A; El-Khatib, Aiman S

    2016-01-01

    Liver fibrosis is one of the most serious consequences of S. mansoni infection. The aim of the present study was to investigate the potential anti-fibrotic effect of human Wharton's jelly-derived mesenchymal stem cells (WJMSCs) combined with praziquantel (PZQ) in S. mansoni-infected mice. S. mansoni-infected mice received early (8(th) week post infection) and late (16(th) week post infection) treatment with WJMSCs, alone and combined with oral PZQ. At the 10(th) month post infection, livers were collected for subsequent flow cytometric, histopathological, morphometric, immunohistochemical, gene expression, and gelatin zymographic studies. After transplantation, WJMSCs differentiated into functioning liver-like cells as evidenced by their ability to express human hepatocyte-specific markers. Regression of S. mansoni-induced liver fibrosis was also observed in transplanted groups, as evidenced by histopathological, morphometric, and gelatin zymographic results besides decreased expression of three essential contributors to liver fibrosis in this particular model; alpha smooth muscle actin, collagen-I, and interleukin-13. PZQ additionally enhanced the beneficial effects observed in WJMSCs-treated groups. Our results suggest that combining WJMSCs to PZQ caused better enhancement in S. mansoni-induced liver fibrosis, compared to using each alone. PMID:26876222

  13. Efficacy of bath and orally administered praziquantel and fenbendazole against Lepidotrema bidyana Murray, a monogenean parasite of silver perch, Bidyanus bidyanus (Mitchell).

    PubMed

    Forwood, J M; Harris, J O; Deveney, M R

    2013-11-01

    We investigated the efficacy of praziquantel (PZQ) and fenbendazole (FBZ), each administered by bath and orally, against the monogenean Lepidotrema bidyana Murray, a gill parasite of the freshwater fish silver perch, Bidyanus bidyanus (Mitchell). PZQ and FBZ were each administered by bath at 10 mg L⁻¹ for 48 h and on surface-coated feed pellets at 75 mg kg⁻¹ per body weight (BW) per day for 6 days. Bath treatments of PZQ and FBZ had an efficacy of 99% and 91%, respectively, against adult L. bidyana. Oral treatments of PZQ and FBZ had an efficacy of 79% and 95%, respectively, against adult L. bidyana. Fish rejected feed pellets surface-coated with PZQ, suggesting that palatability of surface-coated PZQ-medicated feed is poor, which undermined efficacy. In all trials, some juvenile parasites were present on fish after treatment during efficacy assessment, indicating that efficacy may be lower against juvenile parasites or that recruitment occurred post-treatment, demonstrating that repeat treatments are necessary to effectively control L. bidyana in aquaculture. PMID:23488766

  14. Efficacy of Drontal Flavour Plus (50 mg praziquantel, 144 mg pyrantel embonate, 150 mg febantel per tablet) against Giardia sp in naturally infected dogs.

    PubMed

    Montoya, Ana; Dado, Diana; Mateo, Marta; Espinosa, Carmen; Miró, Guadalupe

    2008-10-01

    The therapeutic efficacy of praziquantel, pyrantel embonate and febantel (Drontal Flavour Plus) for three and five consecutive days was evaluated for treating naturally acquired giardiasis in dogs. In the study, 24 dogs naturally infected with Giardia were divided into three groups of eight dogs each. Dogs were treated at the recommended dosage for three or five consecutive days, and a control group remained untreated. Faecal samples from each dog were submitted to coprological examination from day-4 to -2 and at days 5, 7, 9 and 11. Faecal consistency was also assessed daily to study end. All dogs in the control group remained positive until study end. Giardia cysts were not detected in faeces of six of the eight dogs in the group treated on three consecutive days, and in faeces of five of the dogs in the group treated on five consecutive days. Unformed to diarrhoeic faeces were more often reported in dogs in the untreated control group than in dogs in both treatment groups. Efficacy of treatment for five consecutive days was not statistically better than treatment for three consecutive days. PMID:18661153

  15. [Clinico-immunologic indices of various patient contingents in a focus of chronic opisthorchiasis. 3. Dynamics of the indices following praziquantel treatment].

    PubMed

    Parfenov, S B; Ozeretskovskaia, N N; Pomigalov, A Iu; Chistiakova, I V

    1989-01-01

    Studies of the time course of the immune status characteristics after praziquantel treatment and of the nature of its side-effects on various groups of opisthorchiasis patients in the focus established significant differences in their immune response to specific treatment. The lack of alterations in the T- and B-immunity systems in aboriginal population of the focus may suggest its tolerance to helminthic antigens. The trend towards cellular immunity stimulation and a significant increase in the levels of circulating immune complexes and specific antibodies in the serum were observed in aboriginal population of the focus. The comers showed significant initial alterations of the immunity status before treatment, pointing to their sensitization to parasitic antigens. Suppression of the infection normalizes several cellular and humoral immunity characteristics--the number of T-helpers, T-lymphocytes, B-lymphocytes, Th/Tc indices, T-lymphocyte functional activity, thus eliminating immune depression. The increased IgG, CIC and specific antibody levels significantly exceeding the normal level, occurrence or enhancement of allergic reactions point to the necessity of performing a desensitizing therapy and using effective cholagogic drugs in the multimodality treatment to rapidly eliminate the parasitic antigen. PMID:2811752

  16. A Latent Markov Modelling Approach to the Evaluation of Circulating Cathodic Antigen Strips for Schistosomiasis Diagnosis Pre- and Post-Praziquantel Treatment in Uganda

    PubMed Central

    Koukounari, Artemis; Donnelly, Christl A.; Moustaki, Irini; Tukahebwa, Edridah M.; Kabatereine, Narcis B.; Wilson, Shona; Webster, Joanne P.; Deelder, André M.; Vennervald, Birgitte J.; van Dam, Govert J.

    2013-01-01

    Regular treatment with praziquantel (PZQ) is the strategy for human schistosomiasis control aiming to prevent morbidity in later life. With the recent resolution on schistosomiasis elimination by the 65th World Health Assembly, appropriate diagnostic tools to inform interventions are keys to their success. We present a discrete Markov chains modelling framework that deals with the longitudinal study design and the measurement error in the diagnostic methods under study. A longitudinal detailed dataset from Uganda, in which one or two doses of PZQ treatment were provided, was analyzed through Latent Markov Models (LMMs). The aim was to evaluate the diagnostic accuracy of Circulating Cathodic Antigen (CCA) and of double Kato-Katz (KK) faecal slides over three consecutive days for Schistosoma mansoni infection simultaneously by age group at baseline and at two follow-up times post treatment. Diagnostic test sensitivities and specificities and the true underlying infection prevalence over time as well as the probabilities of transitions between infected and uninfected states are provided. The estimated transition probability matrices provide parsimonious yet important insights into the re-infection and cure rates in the two age groups. We show that the CCA diagnostic performance remained constant after PZQ treatment and that this test was overall more sensitive but less specific than single-day double KK for the diagnosis of S. mansoni infection. The probability of clearing infection from baseline to 9 weeks was higher among those who received two PZQ doses compared to one PZQ dose for both age groups, with much higher re-infection rates among children compared to adolescents and adults. We recommend LMMs as a useful methodology for monitoring and evaluation and treatment decision research as well as CCA for mapping surveys of S. mansoni infection, although additional diagnostic tools should be incorporated in schistosomiasis elimination programs. PMID:24367250

  17. Profiling Nonrecipients of Mass Drug Administration for Schistosomiasis and Hookworm Infections: A Comprehensive Analysis of Praziquantel and Albendazole Coverage in Community-Directed Treatment in Uganda

    PubMed Central

    Chami, Goylette F.; Kontoleon, Andreas A.; Bulte, Erwin; Fenwick, Alan; Kabatereine, Narcis B.; Tukahebwa, Edridah M.; Dunne, David W.

    2016-01-01

    Background. Repeated mass drug administration (MDA) with preventive chemotherapies is the mainstay of morbidity control for schistosomiasis and soil-transmitted helminths, yet the World Health Organization recently reported that less than one-third of individuals who required preventive chemotherapies received treatment. Methods. Coverage of community-directed treatment with praziquantel (PZQ) and albendazole (ALB) was analyzed in 17 villages of Mayuge District, Uganda. National drug registers, household questionnaires, and parasitological surveys were collected to track 935 individuals before and after MDA. Multilevel logistic regressions, including household and village effects, were specified with a comprehensive set of socioeconomic and parasitological variables. The factors predicting who did not receive PZQ and ALB from community medicine distributors were identified. Results. Drug receipt was correlated among members within a household, and nonrecipients of PZQ or ALB were profiled by household-level socioeconomic factors. Individuals were less likely to receive either PZQ or ALB if they had a Muslim household head or low home quality, belonged to the minority tribe, or had settled for more years in their village. Untreated individuals were also more likely to belong to households that did not purify drinking water, had no home latrine, and had no members who were part of the village government. Conclusions. The findings demonstrate how to locate and target individuals who are not treated in MDA. Infection risk factors were not informative. In particular, age, gender, and occupation were unable to identify non-recipients, although World Health Organization guidelines rely on these factors. Individuals of low socioeconomic status, minority religions, and minority tribes can be targeted to expand MDA coverage. PMID:26409064

  18. Efficacy of a novel topical combination of fipronil, (S)-methoprene, eprinomectin and praziquantel against adult and immature stages of the cat flea (Ctenocephalides felis) on cats.

    PubMed

    Baker, Christine; Tielemans, Eric; Prullage, Joseph B; Chester, S Theodore; Knaus, Martin; Rehbein, Steffen; Fourie, Josephus J; Young, David R; Everett, William R; Rosentel, Joseph K

    2014-04-28

    The efficacy of a novel topical combination of fipronil 8.3% (w/v), (S)-methoprene 10% (w/v), eprinomectin 0.4% (w/v) and praziquantel 8.3% (w/v) (BROADLINE(®)) was tested against adult and immature stages of Ctenocephalides felis fleas in six studies. For that purpose, fleas from different colonies from North America, Germany and South Africa were used to induce infestations in cats under laboratory conditions. In each study, between 12 and 16 cats were allocated randomly to 2 groups. Cats in Group 1 were not treated and served as controls. Cats in Group 2 were treated once on Day 0 with BROADLINE(®) at the minimum recommended dosage of 0.12 mg/kg body weight. In 4 studies, all animals were infested experimentally with unfed C. felis (100 ± 5) on Days 2 (or 1), 7, 14, 21, 28 and 35. Live fleas were counted 24h post-treatment or infestation. In 2 additional studies, animals were infested at the same frequency with gravid C. felis fleas (100 ± 5) that were fed previously on an untreated host. Forty-eight hours post-infestation, flea eggs were collected, counted and incubated for the evaluation of the reduction of emergence of adults. The combined curative efficacy against adult fleas at 24h after treatment was 94.3% and the combined preventive efficacy values remained greater than 95.9% at 24h after 5 subsequent weekly infestations. In addition, the product reduced dramatically the emergence of new adult fleas for at least 5 weeks (>98.1% for one month and 93.2% at 5 weeks after infestation), demonstrating its efficiency in preventing environmental contamination by immature stages. PMID:24703078

  19. CD4+CD25hiFOXP3+ Regulatory T Cells and Cytokine Responses in Human Schistosomiasis before and after Treatment with Praziquantel

    PubMed Central

    Janse, Jacqueline J.; de Gier, Brechje; Adegnika, Ayôla A.; Issifou, Saadou; Kremsner, Peter G.; Smits, Hermelijn H.; Yazdanbakhsh, Maria

    2015-01-01

    Background Chronic schistosomiasis is associated with T cell hypo-responsiveness and immunoregulatory mechanisms, including induction of regulatory T cells (Tregs). However, little is known about Treg functional capacity during human Schistosoma haematobium infection. Methodology CD4+CD25hiFOXP3+ cells were characterized by flow cytometry and their function assessed by analysing total and Treg-depleted PBMC responses to schistosomal adult worm antigen (AWA), soluable egg antigen (SEA) and Bacillus Calmette-Guérin (BCG) in S. haematobium-infected Gabonese children before and 6 weeks after anthelmintic treatment. Cytokines responses (IFN-γ, IL-5, IL-10, IL-13, IL-17 and TNF) were integrated using Principal Component Analysis (PCA). Proliferation was measured by CFSE. Principal Findings S. haematobium infection was associated with increased Treg frequencies, which decreased post-treatment. Cytokine responses clustered into two principal components reflecting regulatory and Th2-polarized (PC1) and pro-inflammatory and Th1-polarized (PC2) cytokine responses; both components increased post-treatment. Treg depletion resulted in increased PC1 and PC2 at both time-points. Proliferation on the other hand, showed no significant difference from pre- to post-treatment. Treg depletion resulted mostly in increased proliferative responses at the pre-treatment time-point only. Conclusions Schistosoma-associated CD4+CD25hiFOXP3+Tregs exert a suppressive effect on both proliferation and cytokine production. Although Treg frequency decreases after praziquantel treatment, their suppressive capacity remains unaltered when considering cytokine production whereas their influence on proliferation weakens with treatment. PMID:26291831

  20. Factors associated with coverage of praziquantel for schistosomiasis control in the community-direct intervention (CDI) approach in Mali (West Africa)

    PubMed Central

    2013-01-01

    Background Despite the progress made in the control of Neglected Tropical Diseases (NTD), schistosome and soil-transmitted helminth infections are far from being effectively managed in many parts of the world. Chemotherapy, the key element of all control strategies, is faced with some difficulties in terms of access to treatment. Our study aims to describe the factors involved in the success or failure of the community-directed intervention (CDI) approach through control programmes, which aims to achieve consistent high coverage at affordable and sustainable costs in endemic areas. Methods The CDI approach was carried out from December 2007 to October 2008 in ten villages of the district of Diéma, Mali. At inclusion, each child part of the study’s sample was interviewed and submitted for a physical examination. The study focused on: data collection, treatment of the eligible population, evaluation of the treatment coverage, performance of community drug distributors (CDDs), and the involvement and perception of populations. Results A total of 8,022 eligible people were studied with a mean coverage rate of 76.7%. Using multiple regression, it was determined that receiving praziquantel as treatment was associated with five factors: belonging to the Fulani or Moorish ethnic minority versus the Bambara/Soninke, use of the central versus the house-to-house drug distribution mode, the ratio of the population to the number of CDDs, the lack of supervision and belonging to the age group of 15 years or above (p<0.05). As well as that, it was found that the presence of parallel community-based programmes (HIV, tuberculosis) that provide financial incentives for community members discouraged many CDDs (who in most cases are volunteers) to participate in the CDI approach due to a lack of incentives. Conclusions The findings indicate that the success of the CDI approach depends on, amongst other things, the personal characteristics of the respondents, as well as on community

  1. Lipid peroxidation and etheno DNA adducts in white blood cells of liver fluke-infected patients: protection by plasma alpha-tocopherol and praziquantel.

    PubMed

    Dechakhamphu, Somkid; Pinlaor, Somchai; Sitthithaworn, Paiboon; Nair, Jagadeesan; Bartsch, Helmut; Yongvanit, Puangrat

    2010-01-01

    Chronic infection by the liver fluke Opisthorchis viverrini is a strong risk factor for cholangiocarcinoma. To clarify the involvement of oxidative stress and lipid peroxidation-derived DNA damage, etheno (epsilon)-DNA adducts (epsilondA, epsilondC) in WBC and plasma alpha-tocopherol were measured in samples collected from O. viverrini-infected Thai patients (n = 50) and healthy noninfected volunteers (n = 20). epsilondA and epsilondC levels were three to five times higher (P < 0.001) in infected patients than in controls; O. viverrini infection also increased two to three times in the plasma inflammatory indicators, 8-isoprostane, malondialdehyde, and nitrate/nitrite. Mean plasma alpha-tocopherol levels were two times lower in patients than in healthy controls (P < 0.001). Two months after a single dose to infected patients of the antiparasitic drug praziquantel, epsilondA and epsilondC levels in WBC were decreased to control level (P < 0.03); plasma 8-isoprostane, malondialdehyde, nitrate/nitrite, and alkaline phosphatase (ALP) were concomitantly lowered. epsilondA and epsilondC levels in WBC were positively correlated with plasma 8-isoprostane, malondialdehyde, and nitrate/nitrite levels and ALP activity, whereas plasma alpha-tocopherol levels showed inverse correlations. We conclude that chronic O.viverrini infection induces an accumulation of lipid peroxidation-derived DNA damage through oxidative/nitrative stress, which is lowered by the plasma alpha-tocopherol and by antiparasitic drug therapy. Etheno adducts in WBC and urine should be explored as a risk marker for opisthorchiasis-related cholangiocarcinoma, and to assess the efficacy of preventive and therapeutic interventions. PMID:20056652

  2. DK UMa: A Star on the Ascent

    NASA Technical Reports Server (NTRS)

    Simon, Theodore

    1999-01-01

    DK UMa (= 24 UMa = HD 82210) is a G4 IV-III star. According to its M(sub v) and B - V color, it is located at the base of the red giant branch, having recently exited from the Hertzsprung Gap. Now poised to start its first ascent along the giant branch, DK UMa is at a significant juncture in its post-main-sequence evolution, offering an important evolutionary comparison for magnetic activity with stars like 31 Comae, which is just entering the Hertzsprung Gap, and older stars like the Hyades giants or P Ceti, which have passed the tip of the giant branch and lie in the so-called 'clump'. As part of a major survey of the ultraviolet and X ray properties of a well-defined sample of evolved giant stars, DK UMa was observed with the Extreme Ultraviolet Explorer (EUVE) spacecraft in March 1997, for a total exposure time of 230 kiloseconds. A plot of the extracted short-wavelength (SW) spectrum of this star is shown, where it is compared with similar EUVE exposures for other yellow and red giant stars in the activity survey. In terms of the spectral lines of different ionization stages present in these spectra, the transition region and coronal temperature of DK UMa appears to be intermediate between those of 31 Com and P Ceti. Combining the relative strengths of the EUVE lines with Hubble Space Telescope (HST) data at near UV wavelengths and with ROSAT X-ray fluxes, the differential emission measure (DEM) distributions of these stars form a sequence in coronal temperature, which peaks at 10(exp 7.2) K for 31 Com, at 10(exp 6.8) K for B Ceti, and at intermediate temperatures for DK UMa - consistent with the evolutionary stages represented by the three stars. The integrated fluxes of the strongest emission lines found in the EUVE spectrum of DK UMa are listed, again compared with similar measurements for other giant stars that were observed in the course of other EUVE Guest Observer programs.

  3. Astronomia cultural e meio ambiente segundo uma abordagem holística

    NASA Astrophysics Data System (ADS)

    Jafelice, L. C.

    2003-08-01

    Neste trabalho ampliamos a discussão da abordagem holística para o ensino de astronomia que temos desenvolvido nos últimos anos, analisamos novos resultados e apresentamos exemplos práticos para interessados em experimentá-la. A constatação básica a orientar este enfoque é que cursos introdutórios em astronomia costumam ser excessiva e prematuramente técnicos, além de assumirem uma visão tradicional, muito estreita, do que seja educação científica, herdada da era cartesiana e positivista da ciência. Fundamentamos porque é importante que elementos de astronomia cultural ofereçam o mote e constituam o eixo norteador daqueles cursos e porque é urgente revermos a visão que temos da relação entre astronomia e meio ambiente. Um ponto central nesta abordagem é explorar formas de reativar e atualizar uma relação orgânica com o meio e excitar a consciência de nossa inevitável e profunda interdependência com ele em nível cósmico. Neste trabalho exemplificamos a possibilidade de concretização desta proposta em três diferentes situações: disciplinas de cursos de licenciatura em geografia e em física; escolas de nível fundamental; e, neste caso ainda a ser implementada, comunidades carentes. Estes casos envolvem públicos e espaços diferenciados para educação formal e não-formal. Dos casos já implementados, destacamos os resultados alcançados pelos alunos: enriquecimento cultural, aprendizagem significativa de conteúdos astronômicos tradicionais; mudanças de comportamento, incorporando contato diário com o céu; e freqüentes vivências de sentimentos empáticos que redirecionam a relação com a natureza e a consciência ecológica global. Além disto, para interessados em aplicar esta proposta, também socializamos procedimentos e cuidados para a implementação de ações alternativas consonantes com a mesma. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP)

  4. Establishing the Empirical Relationship Between Non-Science Majoring Undergraduate Learners' Spatial Thinking Skills and Their Conceptual Astronomy Knowledge. (Spanish Title: Estableciendo Una Relación Empírica Entre el Razonamiento Espacial de los Estudiantes de Graduación de Carreras no Científicas y su Conocimento Conceptual de la Astronomía.) Estabelecendo Uma Relação Empírica Entre o RacioCínio Espacial dos Estudantes de Graduação EM Carreiras Não Científicas e Seu Conhecimento Conceitual da Astronomia

    NASA Astrophysics Data System (ADS)

    Heyer, Inge; Slater, Stephanie J.; Slater, Timothy F.

    2013-12-01

    normalizadas, en el desempeño de los estudiantes en estos dos asuntos foram pequenas, 0.26 e 0.13 respectivamente. El razonamiento espacial de los estudiantes fue medido utilizando un instrumento específico desarrollado para este trabaljo. Las correlaciones entre los resultados de los tests astronómicos y este instrumento específico, antes y después del curso mostraron una relación entre moderada y fuerte, sugiriendo que la relación entre el razonamiento espacial y el conocimiento astronómico puede explicar hasta un 25% de la variación em el desempeño de los estudiantes. A comunidade da educação em astronomia tem suposto de forma implícita que o aprendizado da astronomia consiste em um domínio conceitual fundamentado no raciocínio espacial. Como um primeiro passo para identificar formalmente uma relação empírica entre estas duas coisas, utilizamos como amostra os estudantes de graduação de carreiras não científicas de um curso exploratório em uma universidade norte-americana do meio-oeste de médio porte com programa de Doutorado em andamento, onde estes estudantes foram submetidos a um diagnóstico de raciocino espacial e conceitos astronômicos antes e depois do mesmo. As ferramentas utilizadas foram o Test Of Astronomy Standards (TOAST) e o questionário What do you know? Utilizando somente dados completamente consistentes para esta análise, nossa amostra consistiu de 86 estudantes de graduação. As melhoras, depois de normalizadas, do desempenho dos estudantes nos dois quesitos foram pequenas, 0.26 e 0.13 respectivamente. O raciocínio espacial dos estudantes foi medido utilizando um instrumento específico desenhado para este trabalho. As correlações entre os resultados dos testes astronômicos e este instrumento específico antes e depois do curso mostraram uma relação entre moderada e forte, sugerindo que a relação entre o raciocínio espacial e o conhecimento astronômico pode explicar até um 25% na variação no desempenho dos

  5. Sustaining Control of Schistosomiasis Mansoni in Western Côte d’Ivoire: Results from a SCORE Study, One Year after Initial Praziquantel Administration

    PubMed Central

    Assaré, Rufin K.; Tian-Bi, Yves-Nathan T.; Yao, Patrick K.; N’Guessan, Nicaise A.; Ouattara, Mamadou; Yapi, Ahoua; Coulibaly, Jean T.; Meïté, Aboulaye; Hürlimann, Eveline; Knopp, Stefanie; Utzinger, Jürg; N’Goran, Eliézer K.

    2016-01-01

    Background The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) has launched several large-scale trials to determine the best strategies for gaining and sustaining control of schistosomiasis and transitioning toward elimination. In Côte d’Ivoire, a 5-year cluster-randomized trial is being implemented in 75 schools to sustain the control of schistosomiasis mansoni. We report Schistosoma mansoni infection levels in children one year after the initial school-based treatment (SBT) with praziquantel and compare with baseline results to determine the effect of the intervention. Methodology The baseline cross-sectional survey was conducted in late 2011/early 2012 and the first follow-up in May 2013. Three consecutive stool samples were collected from 9- to 12-year-old children in 75 schools at baseline and 50 schools at follow-up. Stool samples were subjected to duplicate Kato-Katz thick smears. Directly observed treatment (DOT) coverage of the SBT was assessed and the prevalence and intensity of S. mansoni infection compared between baseline and follow-up. Principal Findings The S. mansoni prevalence in the 75 schools surveyed at baseline was 22.1% (95% confidence interval (CI): 19.5–24.4%). The DOT coverage was 84.2%. In the 50 schools surveyed at baseline and one year after treatment, the overall prevalence of S. mansoni infection decreased significantly from 19.7% (95% CI: 18.5–20.8%) to 12.8% (95% CI: 11.9–13.8%), while the arithmetic mean S. mansoni eggs per gram of stool (EPG) among infected children slightly increased from 92.2 EPG (95% CI: 79.2–105.3 EPG) to 109.3 EPG (95% CI: 82.7–135.9 EPG). In two of the 50 schools, the prevalence increased significantly, despite a DOT coverage of >75%. Conclusions/Significance One year after the initial SBT, the S. mansoni prevalence had decreased. Despite this positive trend, an increase was observed in some schools. Moreover, the infection intensity among S. mansoni-infected children

  6. Flip-flop Activity on the W UMa-type Binary System HH UMa

    NASA Astrophysics Data System (ADS)

    Wang, Kun; Zhang, Xiaobin; Deng, Licai; Luo, Changqing; Luo, Yangping; Zhang, Jun

    2015-05-01

    We report the discovery of flip-flop activity in a W UMa-type binary. A long-term multi-color photometric surveillance of HH UMa was carried out with three sets of light curves obtained over six weeks. The light curves of the eclipsing binary presented marked asymmetry and rapid interchange between the two light maxima. During the observations from 2014 February to 2014 April, the spot distortion phase jumped between phases 0.25 and 0.75 twice, a typical indication of flip-flop activity. We applied the Wilson-Devinney method to analyze the three light curves. The results indicate that HH UMa is a partially eclipsing contact system of A subtype with an obviously asymmetric light curve. The observed light curves can be modeled by assuming that there are two dark spots on the massive primary component that are almost persistently located around phases 0.25 and 0.75, but can interchange their intensities. We further suggest that a plausible scenario for explaining the properties of those dark spots is strong surface magnetic activity with a sudden reversal of the more active longitude. We therefore conclude that HH UMa is very likely a W UMa-type system displaying flip-flop activity.

  7. Imagens do céu ontem e hoje - um multimídia interativo de astronomia e uma nova exposição no MAST

    NASA Astrophysics Data System (ADS)

    Caretta, C. A.; Lima, F. P.; Requeijo, F.; Vieira, G. G.; Alves, F.; Valente, M. E. A.; de Almeida, R.; de Garcia, G. C.; Quixadá, A. C.

    2003-08-01

    "Imagens do Céu Ontem e Hoje" é o título de uma nova exposição que está sendo inaugurada no Museu de Astronomia e Ciências Afins (MCT), que inclui experimentos interativos, maquetes, réplicas e 8 terminais de computador com um multimídia interativo sobre Astronomia para consulta dos visitantes. O multimídia apresenta um conteúdo bastante extenso, que engloba quase todos os temas em Astronomia, consistindo numa fonte de divulgação e pesquisa para um público que vai das crianças até estudantes universitários. O conteúdo está distribuído em mais de 500 páginas de texto divididas em 4 módulos: "O Universo", "Espectroscopia", "Telescópios" e "Observando o Céu". Cada módulo é subdividido em 5 seções, em média, cada uma iniciada por uma animação que ilustra os temas a serem abordados na seção. Ao final da animação, uma lista de temas é apresentada sob o título "Saiba Mais". Para exemplificar, o módulo "O Universo" contém as seguintes seções: "O Universo visto pelo homem", "Conhecendo o Sistema Solar", "Indo além do Sistema Solar", "Nossa Galáxia, a Via-Láctea" e "Indo mais além, a imensidão do Universo". A seção "Conhecendo o Sistema Solar", por sua vez, tem os seguintes temas: "A origem do Sistema Solar", "O Sol", "Os planetas", "Satélites, asteróides, cometas e outros bichos..." e "O Sistema Solar em números". Cada texto é repleto de imagens, quadros, desenhos, esquemas, etc, além de passatempos ao final de cada seção, incluindo jogos interativos, quadrinhos e curiosidades, que auxiliam o aprendizado de forma divertida. Apresentamos neste trabalho as idéias gerais que permearam a produção da exposição, e uma viagem pelo multimídia para exemplificar sua estrutura e conteúdo. O multimídia será posteriormente disponibilizado para o público externo pela página eletrônica do MAst e/ou por intermédio de uma publicação comercial.

  8. Efficacy of a single dose of milbemycin oxime/praziquantel combination tablets, Milpro(®), against adult Echinococcus multilocularis in dogs and both adult and immature E. multilocularis in young cats.

    PubMed

    Cvejic, Dejan; Schneider, Claudia; Fourie, Josephus; de Vos, Christa; Bonneau, Stephane; Bernachon, Natalia; Hellmann, Klaus

    2016-03-01

    Two single-site, laboratory, negatively controlled, masked, randomised dose confirmation studies were performed: one in dogs, the other in cats. After a period of acclimatisation, both the dogs and cats were orally infected with Echinococcus multilocularis protoscoleces. In the dog study, 10 dogs received a single dose of Milpro® tablets at a minimum dose of 0.5 mg/kg milbemycin oxime and 5 mg/kg praziquantel 18 days post-infection and 10 dogs received no treatment. In the cat study, 10 cats received a single dose of Milpro® tablets at a minimum dose of 2 mg/kg milbemycin oxime and 5 mg/kg praziquantel 7 days post-infection, 10 cats received a single dose of the treatment 18 days post-infection and 10 cats remained untreated. In both studies, intestinal worm counts were performed 23 days post-infection at necropsy. No worms were retrieved from any of the 30 treated animals. Nine of 10 control dogs had multiple worms (geometric mean 91, arithmetic mean 304) and all 10 control cats had multiple worms (geometric mean 216, arithmetic mean 481). The difference in worm counts between all three treated groups and their controls was highly significant (ANOVA p values of log transformed data <0.0001). Efficacy of 100 % was demonstrated for the elimination of adult E. multilocularis in dogs and cats as well as for elimination of immature E. multilocularis in cats as evidenced by the effectiveness of treatment 7 days post-infection. The treatments were well accepted and tolerated, and there were no adverse drug reactions observed. PMID:26660919

  9. High speed photometry of AN UMa

    SciTech Connect

    Imamura, J.N.; Steiman-Cameron, T.Y.; Durisen, R.H.

    1985-01-01

    As a class, the AM Her objects exhibit temporal variability on time scales ranging from seconds to years. Most of the variations can be adequately described by ''shot noise'' models (Cordova and Mason 1982). Exceptions to this are the strictly periodic features modulated on the orbital periods of the systems (typically several hours) and the one to two second features which show up as ''excesses'' of power in the time averaged power spectra of AN UMa (Middleditch 1982) and E1405-451 (Mason et al. 1983; Larsson 1985). It has been suggested that the short time scale features are due to an oscillatory ''instability'' of radiative accretion shocks discovered by Langer, Chanmugam, and Shaviv (1981, 1982). This is an interesting suggestion because, if true, it would allow the masses of the accreting white dwarfs to be inferred and would provide other significant constraints on the physics of the accretion flows (see Langer et al. 1981, 1982; Chevalier and Imamura 1982; Imamura, Wolff, and Durisen 1984; Imamura 1985). Unfortunately, a direct physical relationship between the one to two second optical variations and shock oscillations has not yet been demonstrated. Because of the potential importance of such a result further study of these systems is clearly warranted. In this work, we examine the short time scale behavior of AN UMa in more detail and improve on the work of Middleditch (1982) by resolving the feature in time.

  10. EM International. Volume 1

    SciTech Connect

    Not Available

    1993-07-01

    It is the intent of EM International to describe the Office of Environmental Restoration and Waste Management`s (EM`s) various roles and responsibilities within the international community. Cooperative agreements and programs, descriptions of projects and technologies, and synopses of visits to international sites are all highlighted in this semiannual journal. Focus on EM programs in this issue is on international collaboration in vitrification projects. Technology highlights covers: in situ sealing for contaminated sites; and remote sensors for toxic pollutants. Section on profiles of countries includes: Arctic contamination by the former Soviet Union, and EM activities with Germany--cooperative arrangements.

  11. Propriedades de estruturas temporais rápidas submilimétricas durante uma grande explosão solar

    NASA Astrophysics Data System (ADS)

    Raulin, J.-P.; Kaufmann, P.; Gimenez de Castro, C. G.; Pacini, A. A.; Makhmutov, V.; Levato, H.; Rovira, M.

    2003-08-01

    Apresentamos novas propriedades de variações rápidas da emissão submilimétrica durante uma das maiores explosões solares do ciclo solar 23. Os dados analisados neste estudo foram obtidos com o Telescópio Solar Submilimétrico (SST), que observa o Sol em 212 GHz e 405 GHz, e comparados com emissões em Raios-X duros e Raios-gama (fótons de energia > 10 MeV), que foram obtidas pelo experimento GRS do Yohkoh. Aplicamos diferentes metodologias para detectar e caracterizar, ao longo do evento, os pulsos submilimétricos (duração de 50-300 ms) detectados acima de uma componente mais lenta (alguns minutos). Os resultados mostram que durante a fase impulsiva, num instante próximo ao tempo do máximo do evento, houve um aumento da ocorrência de maiores e de mais rápidas estruturas temporais. Também identificamos uma boa correlação com as emissões em raios-X e raios-gama (até a faixa de energia 10-100 MeV), indicando que os pulsos rápidos submilimétricos refletiram injeções primárias de energia durante o evento.O espectro do fluxo desses pulsos é crescente com a freqüência entre 212 and 405 GHz, na maioria dos casos, ao contrário do observado para a componente gradual. As posições calculadas para as estruturas rápidas são discretas, compactas e localizadas em toda a área da região ativa, o que é previsto nos modelos de explosões solares decorrentes de instabilidades múltiplas em diferentes pequenas regiões. Por outro lado, a posição calculada para a componente lenta é estável durante a fase impulsiva. Assim, a comparação entre as características do espectro de fluxo e da localização da emissão, para os pulsos rápidos e para a componente gradual, sugere que as respectivas emissões são de natureza diferente.

  12. Ondas de choque em jatos de quasares e objetos BL Lacertae

    NASA Astrophysics Data System (ADS)

    Melo, F. E.; Botti, L. C. L.

    2003-08-01

    Este trabalho é parte de um projeto que vem sendo realizado há dois anos no CRAAM, cujos objetivos principais são analisar e aplicar um modelo generalizado de ondas de choque em jatos relativísticos de plasma, presentes em quasares e objetos BL Lacertae, para explicar a variabilidade observada nestes objetos. O método consiste em uma decomposição de curvas de luz em séries de explosões similares, em várias freqüências, baseando-se em uma evolução espectro-temporal média das explosões. A partir da evolução média, um ajuste de cada explosão é feito com base em equações empíricas, modificando-se apenas parâmetros específicos de cada explosão. Inicialmente o modelo foi aplicado ajustando-se as curvas de luz a explosões delineadas por uma evolução do choque em três estágios, segundo a predominância do processo de emissão: síncrotron, Compton e adiabático. Entretanto, nesta nova fase de projeto, visando uma parametrização mais concisa, uma otimização do algoritmo de ajuste e uma convergência mais rápida, a formulação para cada evento foi assumida com uma evolução em apenas dois estágios: subida e descida. Isto possibilitou uma ótima delineação das curvas de luz das fontes OV236, OJ287, 3C273 e BL Lac, entre 1980 e 2000, nas freqüências 4.8, 8.0, 14.5 e 22 GHz, utilizando-se dados do Observatório da Universidade de Michigan, do Observatório do Itapetinga (Atibaia SP) e do Observatório Metsähovi. Como conclusões importantes, verificou-se que: os parâmetros ajustados descrevem o comportamento do jato; os valores do índice que descreve a expansão do jato sugerem que o mesmo se expande de uma forma não-cônica; o campo magnético é turbulento atrás da frente de choque; e as peculiaridades das explosões são devidas à influência de grandezas tais como o coeficiente da distribuição espectral de energia dos elétrons, a intensidade de campo magnético e o fator de feixe Doppler, no início do choque.

  13. Estudo em microondas do aprisionamento e precipitação de elétrons em explosões solares

    NASA Astrophysics Data System (ADS)

    Rosal, A. C.; Costa, J. E. R.

    2003-08-01

    Uma explosão solar é uma variação rápida e intensa do brilho que ocorre nas chamadas regiões ativas da atmosfera, constituídas por um plasma magnetizado com intensa indução magnética. Os modelos de explosões solares atuais, discutidos na literatura, apresentam características de aprisionamento e precipitação de elétrons em ambientes magnéticos simplificados. Neste trabalho, nos propusemos a separar a emissão dos elétrons aprisionados da emissão dos elétrons em precipitação apenas a partir da emissão em microondas, melhorando portanto o controle sobre o conjunto de parâmetros inferidos. A emissão em microondas da população em precipitação é bastante fraca e portanto da nossa base de dados de 130 explosões observadas pelo Rádio Polarímetro de Nobeyama, em sete freqüências, apenas para 32 foi possível separar as duas componentes de emissão com uma boa razão sinal/ruído. A partir de estudos das escalas de tempo das emissões devidas à variação gradual da emissão no aprisionamento e da variação rápida da emissão dos elétrons em precipitação foi possível obter a separação utilizando um filtro temporal nas emissões resultantes. Em nossa análise destas explosões estudamos os espectros girossincrotrônicos da emissão gradual, a qual associamos provir do topo dos arcos magnéticos e da emissão de variação rápida associada aos elétrons em precipitação. Estes espectros foram calculados e dos quais inferimos que a indução magnética efetiva do topo e dos pés foi em média, Btopo = 236 G e Bpés = 577 G, inferidas das freqüências de pico dos espectros em ntopo = 11,8 GHz e npés = 14,6 GHz com leve anisotropia (pequeno alargamento espectral). O índice espectral da distribuição não-térmica de elétrons d, inferido do índice espectral de fótons da emissão em regime opticamente fino, foi de dtopo = 3,3 e dpés = 3,9. Estes parâmetros são típicos da maioria das análises realizadas em ambiente único de

  14. Discovery of a New Deeply Eclipsing SU UMa-Type Dwarf Nova, IY UMa (= TmzV 85)

    NASA Astrophysics Data System (ADS)

    Uemura, Makoto; Kato, Taichi; Matsumoto, Katsura; Takamizawa, Kesao; Schmeer, Patrick; Jensen, Lasse Teist; Vanmunster, Tonny; Novák, Rudolf; Martin, Brian; Pietz, Jochen; Buczynski, Denis; Kinnunen, Timo; Moilanen, Marko; Oksanen, Arto; Cook, Lewis M.; Watanabe, Tsutomu; Maehara, Hiroyuki; Itoh, Hiroshi

    2000-04-01

    We discovered a new deeply eclipsing SU UMa-type dwarf nova, IY UMa, which experienced a superoutburst in 2000 January. Our monitoring revealed two distinct outbursts, which suggest a superoutburst interval of ~ 800 d, or its half, and an outburst amplitude of 5.4 mag. From time-series photometry during the superoutburst, we determined a superhump and orbital period of 0.07588 d and 0.0739132 d, respectively.

  15. Estudo comparativo entre estrelas centrais de nebulosas planetárias deficientes em hidrogênio

    NASA Astrophysics Data System (ADS)

    Marcolino, W. L. F.; de Araújo, F. X.

    2003-08-01

    Apresentamos neste trabalho o resultado de um estudo das principais características espectrais das estrelas centrais de nebulosas planetárias (ECNP) deficientes em hidrogênio. A origem e a evolução dessas estrelas ainda constitui um problema em aberto na evolução estelar. Geralmente esses objetos são divididos em [WCE], [WCL] e [WELS]. Os tipos [WCE] e [WCL] apresentam um espectro típico de uma estrela Wolf-Rayet carbonada de população I e as [WELS] apresentam linhas fracas de carbono e oxigênio em emissão. Existem evidências que apontam a seguinte sequência evolutiva : [WCL] = > [WCE] = > [WELS] = > PG 1159 (pré anã-branca). No entanto, tal cenário apresenta falhas como por exemplo a falta de ECNP entre os tipos [WCL] e [WCE]. Baseados em uma amostra de 24 objetos obtida no telescópio de 1.52m em La Silla, Chile (acordo ESO/ON), ao longo do ano 2000, apresentamos os resultados da comparação das larguras equivalentes de diversas linhas relevantes entre os tipos [WCL], [WCE] e [WELS]. Verificamos que nossos dados estão de acordo com a sequência evolutiva. Baseado nas linhas de C IV, conseguimos dividir pela primeira vez as [WELS] em dois grupos principais. Além disso, os dados reforçam a afirmação de que as [WCE] são as estrelas que possuem a maior temperatura entre as ECNP deficientes em hidrogênio. Discutimos ainda, a escassez de dados disponíveis na literatura e a necessidade da obtenção de parametros físicos para estes objetos.

  16. Detecção inesperada de efeitos de lentes fracas em grupos de galáxias pouco luminosos em raios-X

    NASA Astrophysics Data System (ADS)

    Carrasco, R.; Mendes de Oliveira, C.; Sodrã©, L., Jr.; Lima Neto, G. B.; Cypriano, E. S.; Lengruber, L. L.; Cuevas, H.; Ramirez, A.

    2003-08-01

    Obtivemos, como parte do programa de verificação científica do GMOS Sul, imagens profundas de três grupos de galáxias: G97 e G102 (z~0,4) e G124 (z = 0,17). Esses alvos foram selecionados a partir do catálogo de fontes extensas de Vikhlinin (1998), por terem luminosidades em raios X menores que 3´1043 ergs s-1, valor cerca de uma ou duas ordens de grandeza inferior ao de aglomerados de galáxias. O objetivo primário dessas observações é o estudo da evolução de galáxias em grupos. Grupos são ambientes menos densos que aglomerados, contêm a grande maioria das galáxias do Universo mas que, até o momento, foram estudados detalhadamente apenas no Universo local (z~0). Com esses dados efetuamos uma análise estatística da distorção na forma das galáxias de fundo (lentes gravitacionais fracas) como forma de inferir o conteúdo e a distribuição de massa nesses grupos apesar de que, em princípio, esse efeito não deveria ser detectado uma vez que os critérios de seleção adotados previlegiam sistemas de baixa massa. De fato, para G124 obtivemos apenas um limite superior para sua massa que é compatível com sua luminosidade em raios X. De modo contrário e surpreendente, os objetos G102 e G097, aparentam ter massas que resultariam em dispersões de velocidade maiores que 1000 km s-1, muito maiores do que se espera para grupos de galáxias. Com efeito, para G097 obtivemos, a partir de dados do satélite XMM, uma estimativa para a temperatura do gás intragrupo de kT = 2,6 keV, que é tipica de sistemas com dispersões de velocidade de ~ 600 km s-1, bem característica de grupos. Essas contradições aparentes entre lentes fracas e raios X podem ser explicadas de dois modos: i) a massa obtida por lentes estaria sobreestimada devido à superposição de estruturas massivas ao longo da linha de visada ou ii) a temperatura do gás do meio intra-grupo reflete o potencial gravitacional de estruturas menores que estariam se fundindo para formar uma

  17. Development and validation of an enantioselective LC-MS/MS method for the analysis of the anthelmintic drug praziquantel and its main metabolite in human plasma, blood and dried blood spots.

    PubMed

    Meister, Isabel; Leonidova, Anna; Kovač, Jana; Duthaler, Urs; Keiser, Jennifer; Huwyler, Jörg

    2016-01-25

    Praziquantel (PZQ) is the treatment of choice against various trematode and cestode infections. To study the pharmacokinetics of PZQ in patients infected with the liver fluke Opisthorchis viverrini, we developed and validated an enantioselective liquid chromatography coupled to tandem mass spectrometry method for the analysis of R - and S -PZQ and its R -trans-4-OH-PZQ metabolite in human plasma, blood and dried blood spots (DBS). The analytes were detected in the positive mode using selected reaction monitoring (R- and S-PZQ: m/z 312.2 → 202.2; R-trans -4-OH-PZQ: m/z 328.0 → 202.0). Prior to the chiral separation with a cellulose tris(3-chloro-4-methylphenylcarbamate) column, the analytes were purified from matrix contaminants and concentrated on a C-18 trapping column. The analytical range for each PZQ enantiomer was 0.01-2.5 μg/mL, and 0.1-25 μg/mL for the metabolite. The method met the requirements regarding precision (± 15%, ± 20% at the lower limit of quantification-LLOQ), intra- and inter-assay accuracy (85-115%, 80-120% at LLOQ), and linearity (R(2) ≥ 0.998). The analytes were stable in stock solutions as well as in plasma, blood and DBS. For DBS, the influences of hematocrit and blood spot size were considered as minor. Our validation results show that the method presented here is precise, accurate and selective, and can be used for pharmacokinetic studies. Moreover, the enantioselective separation was achieved with a run time of 11.5 min and a simple sample processing method. PMID:26517852

  18. Field evaluation of the efficacy and the safety of a combination of oxantel/pyrantel/praziquantel in the treatment of naturally acquired gastrointestinal nematode and/or cestode infestations in dogs in Europe.

    PubMed

    Grandemange, E; Claerebout, E; Genchi, C; Franc, M

    2007-04-10

    In five multicentre field trials, the efficacy and safety of a combination of oxantel/pyrantel/praziquantel (Dolpac), Vetoquinol SA) in the treatment of naturally acquired gastrointestinal nematode and/or cestode infestation in dogs was evaluated in northern and southern Europe. Forty-eight investigators from France, Belgium, Germany, Italy and Spain enrolled 329 dogs to be treated with the tested combination; 235 of these dogs complied with the inclusion criteria of the protocol and had a tested helminth identified on Day 0. A pooled analysis was performed on each of the following helminth species: Toxocara canis, Ancylostoma caninum, Toxascaris leonina, Trichuris vulpis, Uncinaria stenocephala, Taenia spp. and Dipylidium caninum, which were isolated on Day 0. The main efficacy criterion was the egg per gram (epg) percent reduction of the nematodes and the absence of proglottids and or eggs for the cestodes. After treatment, dogs were examined on Day 7, Day 14 and Day 21. The efficacy of the combination against Toxocara canis was 99.1%, 98.8% and 98.9% on Day 7, Day 14 and Day 21, respectively. At the same occasions the efficacy was, respectively, 99.2%, 99.2% and 99.3% against Ancylostoma caninum, 97.3%, 97.2% and 98.4% against Trichuris vulpis, 98.4%, 98.8% and 98.8% against Uncinaria stenocephala, 98.9%, 99.5% and 99.9% against Toxascaris leonina, 97.1%, 100% and 100% against Dipylidium caninum and 100% against Taenia spp. PMID:17184919

  19. Detecção da fase impulsiva de uma explosão solar gigante até 405 GHz

    NASA Astrophysics Data System (ADS)

    Raulin, J.-P.; Makhmutov, V.; Kaufmann, P.; Pacini, A. A.; Luethi, T.; Hudson, H. S.; Gary, D. E.; Yoshimori, M.

    2003-08-01

    A explosão ocorrida no dia 25/08/2001 foi uma das mais intensas do presente ciclo solar em ondas de rádio de altas frequências. Foram medidas em ondas milimétricas e submilimétricas, aproximadamente, 105 e vários milhares de unidades de fluxo solar, respectivamente. Apresentamos um estudo deste evento em múltiplas frequências, desde microondas (1GHz), até ondas submilimétricas (405 GHz) detectadas pelo Telescópio Solar para ondas Submilimétricas (SST). Esta base de dados foi complementada utilizando-se o experimento Yohkoh, incluindo a emissão em raios-X duros e raios-g (até 100 MeV), e imagens em raios-X moles da região ativa envolvida. Enfocamos e discutimos principalmente os seguintes aspectos da fase impulsiva do evento: (i) as implicações deduzidas do espectro eletromagnético, obtido pela primeira vez até 405 GHz; (ii) a dinâmica da região ativa. Os resultados mostram que para explicar o espectro rádio observado, são necessários entre 3.5×1037 e 1.5×1039 elétrons acelerados acima de 20 keV em uma região de campo magnético entre 300 e 800 Gauss. A estimativa do fluxo de fótons que seria produzido por estes elétrons, mostra que grande parte deles não precipitou na baixa atmosfera. A evolução temporal da emissão em raios-X moles revela que a configuração magnética da região ativa foi muito dinâmica durante a fase impulsiva da explosão. Em particular, mostramos que a produção dos elétrons altamente energéticos foi iniciada junto com a aparição, na baixa coroa solar, de um novo sistema compacto de estruturas magnéticas. Este fato sugere que os locais de aceleração estão localizados na baixa atmosfera do Sol, como resultado da interação entre o novo sistema compacto e o campo magnético ambiente da região ativa.

  20. BZ UMa and Var Her 04: Orphan TOADS

    NASA Astrophysics Data System (ADS)

    Price, A.; Howell, S.

    2005-05-01

    Both BZ UMa and Var Her 04 are cataclysmic variable stars without a home. Neither fit easily into current classification systems so may extend the population distribution of two unique CV types: UGWZ dwarf novae and intermediate polars. New outburst photometry and archival X-Ray data shed some new light on BZ UMa's high energy state and new spectral and IR observations from Spitzer of dust around the newly discovered cataclysmic variable Var Her 04 may help find it a home as well.

  1. emGain: Determination of EM gain of CCD

    NASA Astrophysics Data System (ADS)

    Daigle, Olivier; Carignan, Claude; Blais-Ouellette, Sebastien

    2012-01-01

    The determination of the EM gain of the CCD is best done by fitting the histogram of many low-light frames. Typically, the dark+CIC noise of a 30ms frame itself is a sufficient amount of signal to determine accurately the EM gain with about 200 512x512 frames. The IDL code emGain takes as an input a cube of frames and fit the histogram of all the pixels with the EM stage output probability function. The function returns the EM gain of the frames as well as the read-out noise and the mean signal level of the frames.

  2. Pharmacokinetic Study of Praziquantel Enantiomers and Its Main Metabolite R-trans-4-OH-PZQ in Plasma, Blood and Dried Blood Spots in Opisthorchis viverrini-Infected Patients

    PubMed Central

    Meister, Isabel; Kovac, Jana; Duthaler, Urs; Odermatt, Peter; Huwyler, Jörg; Vanobberghen, Fiona; Sayasone, Somphou; Keiser, Jennifer

    2016-01-01

    Background Praziquantel (PZQ) is the treatment of choice for infections with the liver fluke Opisthorchis viverrini, a major health problem in Southeast Asia. However, pharmacokinetic (PK) studies investigating the disposition of PZQ enantiomers (R- and S-PZQ) and its main metabolite, R-trans-4-OH-PZQ, in diseased patients are lacking. The implementation of a dried blood spot (DBS) sampling technique would ease the performance of PK studies in remote areas without clinical facilities. The aim of the present study is to provide data on the disposition of PZQ enantiomers and R-trans-4-OH-PZQ in opisthorchiasis patients and to validate the use of DBS compared to plasma and blood sampling. Methodology/Principal Findings PZQ was administered to nine O. viverrini-infected patients at 3 oral doses of 25 mg/kg in 4 h intervals. Plasma, blood and DBS were simultaneously collected at selected time points from 0 to 24 h post-treatment. PK parameters were determined using non-compartmental analysis. Drug concentrations and areas under the curve (AUC0–24h) measured in the 3 matrices were compared using Bland-Altman analysis. We observed plasma AUC0–24hs of 1.1, 9.0 and 188.7 μg/ml*h and half-lives of 1.1, 3.3 and 6.4 h for R-PZQ, S-PZQ and R-trans-4-OH, respectively. Maximal plasma concentrations (Cmax) of 0.2, 0.9 and 13.9 μg/ml for R-PZQ, S-PQZ and R-trans-4-OH peaked at 7 h for PZQ enantiomers and at 8.7 h for the metabolite. Individual drug concentration measurements and patient AUC0–24hs displayed ratios of blood or DBS versus plasma between 79–94% for R- and S-PZQ, and between 108–122% for R-trans-4-OH. Conclusions/Significance Pharmacodynamic (PD) in vitro studies on PZQ enantiomers and R-trans-4-OH-PZQ are necessary to be able to correlate PK parameters with efficacy. DBS appears to be a valid alternative to conventional venous sampling for PK studies in PZQ-treated patients. PMID:27152952

  3. Chemical Compatibility and Safety of Imidacloprid/Flumethrin Collar (Seresto®) Concomitantly Used with Imidacloprid/Moxidectin (Advocate®, Advantage® Multi) and Emodepside/Praziquantel (Profender®) Spot-on Formulations.

    PubMed

    Krüdewagen, Eva Maria; Remer, Carolin; Deuster, Katrin; Schunack, Bettina; Wolken, Sonja; Crafford, Dionne; Fourie, Josephus; Stanneck, Dorothee

    2015-08-01

    Safety of concomitant use of veterinary products is of clinical interest. A series of studies was performed to evaluate the chemical compatibility and short term dermal and systemic safety of an imidacloprid/flumethrin collar (Seresto(®)/ Foresto(®), Bayer) used concomitantly with spot-on or tablet formulations.Chemical compatibility was evaluated in-vitro (study reference A) on collar pieces, followed by two small, non-controlled clinical studies (study reference B) in both, cats and dogs. The studies showed, that certain solvents affected the collar in-vitro, but not in their marketed formulations.Dermal and systemic safety of different spot-on or tablet formulations was first evaluated in a small, non-controlled clinical study (study reference C) in cats and dogs, via clinical observations only, followed by controlled clinical safety studies of concomitant use with imidacloprid/ moxidectin (Advocate(®)/ Advantage(®) Multi, Bayer) in dogs and cats (study reference D) and emodepside/ praziquantel (Profender(®), Bayer) in cats (study reference E), assessing safety aspects by clinical observations and statistical analyses of hematology and clinical chemistry parameters compared to baseline values and between treated and control groups.Dermal safety findings over all clinical studies (study references B to E) matched those already described for the respective products and included transient cosmetic changes (oily hair and crystal formation) at the site of spot-on application and broken hair, transient alopecia and skin alterations at the site of collar application. There were no indications of these findings aggravating under the conditions of concurrent use. There were no systemic safety findings of clinical significance in any of the clinical safety studies (study reference C to E). Assessment of blood parameters revealed some deviations from baseline levels and from the reference range in dogs as well as in cats, but no clinical relevance could be deduced

  4. Neural network analysis of W UMa eclipsing binaries

    NASA Astrophysics Data System (ADS)

    Zeraatgari, F. Z.; Abedi, A.; Farshad, M.; Ebadian, M.; Riazi, N.

    2015-04-01

    We try five different artificial neural models, four models based on PNN (Perceptron Neural Network), and one using GRNN (Generalized Regression Neural Network) as tools for the automated light curve analysis of W UMa-type eclipsing binary systems. These algorithms, which are inspired by the Rucinski method, are designed and trained using MATLAB 7.6. A total of 17,820 generated contact binary light curves are first analyzed using a truncated cosine series with 11 coefficients and the most significant coefficients are applied as inputs of the neural models. The required sample light curves are systematically generated, using the WD2007 program (Wilson and Devinney 2007). The trained neural models are then applied to estimate the geometrical parameters of seven W UMa-type systems. The efficiency of different neural network models are then evaluated and compared to find the most efficient one.

  5. Evolução temporal de discos circunstelares em estrelas Be

    NASA Astrophysics Data System (ADS)

    Fernandes, M. V. M.; Leister, N. V.; Levenhagen, R. S.

    2003-08-01

    A pesquisa do mecanismo que leva uma estrela do tipo Be a perder massa e formar um envelope circunstelar, nomeado como fenômeno Be, é uma questão em aberto, intrigante, e que adquire contornos interessantes em face às informações espectroscópicas de alta resolução. Nesta última década, consolida-se a idéia de que a forma destes envelopes é de tipo discóide, obedecendo a uma lei Kepleriana de velocidades, e mais ainda, recentemente há evidências de que a distribuição de matéria nestes discos pode assumir um caráter de anel. Medidas de algumas dimensões de discos circunstelares puderam ser obtidas pela análise de espectros de alta resolução e alta relação sinal-ruído para as estrelas Be: alpha Eri (HD 10144, B3Vpe), omicron And (HD 217675, B6IIIpe), e eta Cen (HD el972, B1.5Vne), no período dos anos de 1991 a 2001. Alguns modelos clássicos de envelope predizem uma distribuição de massa que decresce suavemente a partir da superfície estelar. Entretanto, considerando que a separação de picos de emissão em perfis de linhas do HeI e H-alpha, alargados por efeitos cinemáticos, é função do raio estelar e da velocidade rotacional projetada (vsini); nossos resultados sugerem a presença de um anel de matéria circunstelar, que aparece logo após a ejeção do material fotosférico, imediatamente acima da superfície estelar, e que se expande para raios maiores ao longo do tempo, eventualmente desconectando-se da superfície por uma região de densidade de matéria mínima. Tais interpretações revivem a idéia de que anéis de matéria circunstelar podem ser os responsáveis por algumas variabilidades em perfis de linhas de emissão, como as variações V/R.

  6. Astronomia para/com crianças carentes em Limeira

    NASA Astrophysics Data System (ADS)

    Bretones, P. S.; Oliveira, V. C.

    2003-08-01

    Em 2001, o Instituto Superior de Ciências Aplicadas (ISCA Faculdades de Limeira) iniciou um projeto pelo qual o Observatório do Morro Azul empreendeu uma parceria com o Centro de Promoção Social Municipal (CEPROSOM), instituição mantida pela Prefeitura Municipal de Limeira para atender crianças e adolescentes carentes. O CEPROSOM contava com dois projetos: Projeto Centro de Convivência Infantil (CCI) e Programa Criança e Adolescente (PCA), que atendiam crianças e adolescentes em Centros Comunitários de diversas áreas da cidade. Esses projetos têm como prioridades estabelecer atividades prazerosas para as crianças no sentido de retirá-las das ruas. Assim sendo, as crianças passaram a ter mais um tipo de atividade - as visitas ao observatório. Este painel descreve as várias fases do projeto, que envolveu: reuniões de planejamento, curso de Astronomia para as orientadoras dos CCIs e PCAs, atividades relacionadas a visitas das crianças ao Observatório, proposta de construção de gnômons e relógios de Sol nos diversos Centros Comunitários de Limeira e divulgação do projeto na imprensa. O painel inclui discussões sobre a aprendizagem de crianças carentes, relatos que mostram a postura das orientadoras sobre a pertinência do ensino de Astronomia, relatos do monitor que fez o atendimento no Observatório e o que o número de crianças atendidas representou para as atividades da instituição desde o início de suas atividades e, em particular, em 2001. Os resultados são baseados na análise de relatos das orientadoras e do monitor do Observatório, registros de visitas e matérias da imprensa local. Conclui com uma avaliação do que tal projeto representou para as Instituições participantes. Para o Observatório, em particular, foi feita uma análise com relação às outras modalidades de atendimentos que envolvem alunos de escolas e público em geral. Também é abordada a questão do compromisso social do Observatório na educação do

  7. The EM Earthquake Precursor

    NASA Astrophysics Data System (ADS)

    Jones, K. B., II; Saxton, P. T.

    2013-12-01

    Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After the 1989 Loma Prieta Earthquake, American earthquake investigators predetermined magnetometer use and a minimum earthquake magnitude necessary for EM detection. This action was set in motion, due to the extensive damage incurred and public outrage concerning earthquake forecasting; however, the magnetometers employed, grounded or buried, are completely subject to static and electric fields and have yet to correlate to an identifiable precursor. Secondly, there is neither a networked array for finding any epicentral locations, nor have there been any attempts to find even one. This methodology needs dismissal, because it is overly complicated, subject to continuous change, and provides no response time. As for the minimum magnitude threshold, which was set at M5, this is simply higher than what modern technological advances have gained. Detection can now be achieved at approximately M1, which greatly improves forecasting chances. A propagating precursor has now been detected in both the field and laboratory. Field antenna testing conducted outside the NE Texas town of Timpson in February, 2013, detected three strong EM sources along with numerous weaker signals. The antenna had mobility, and observations were noted for recurrence, duration, and frequency response. Next, two

  8. Bioterrorism awareness for EMS.

    PubMed

    Patrick, Richard W

    2004-04-01

    It is important to understand that the issues surrounding bioterrorism and all weapons of mass destruction are complex. In an effort to enhance response to such events, EMS should handle all incidents from the perspective of an all-hazards approach. Prevention, preparation, response and recovery are essential to the safe mitigation of all incidents. Organizations must be prepared. Plan now for a safer tomorrow. Your personnel and communities depend on you. PMID:15131906

  9. 21 CFR 520.1870 - Praziquantel tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...). Administer directly by mouth or crumbled and in feed. (ii) Indications for use—(A) For removal of canine... feed. Not intended for use in kittens less than 6 weeks of age. For OTC use: Consult your...

  10. Uma análise do fenômeno “alternância de línguas” na fala de bilíngues intermodais (Libras e Português)

    PubMed Central

    de Sousa, Aline Nunes; de Quadros, Ronice Müller

    2013-01-01

    Um interessante fenômeno lingüístico presente nas interações das pessoas bilíngues é a alternância de línguas. Neste trabalho, estamos investigando a alternância entre a língua portuguesa oral e a língua de sinais brasileira – Libras, numa mesma cadeia enunciativa, com o objetivo de identificar e analisar o uso dessa alternância na fala de uma criança e de um adulto (ambos ouvintes, filhos de pais surdos), interagindo em uma situação de bilinguismo intermodal, com interlocutores surdos e ouvintes. A alternância de línguas, nesse caso, ocorre quando se para de falar em português e se alterna para sinalizar. O presente trabalho se caracteriza como um estudo inicial, com análise qualitativa de dados. Fazem parte do nosso corpus nove sessões de interações em Libras e em português oral, gravadas em vídeo, que fazem parte do Projeto Desenvolvimento Bilíngue Bimodal da UFSC. Os dados revelam que as características da alternância de línguas pelo adulto e pela criança parecem ter semelhanças e diferenças. O sujeito adulto parece ter feito um uso da alternância mais preocupado com o curso da interação. A criança, por sua vez, não parece tê-la usado com propósitos pragmáticos específicos. Quanto à extensão das alternâncias, pode-se perceber que tanto a criança quanto o adulto utilizaram enunciados maiores do que uma única palavra isolada. O papel dos interlocutores parece ter sido decisivo nas interações aqui investigadas – especialmente nas do adulto, já que a criança ainda está em processo de tomada de consciência do papel do interlocutor na interação. PMID:24379831

  11. Percepção astronómica de um grupo de alunos do ensino médio de uma escola da rede estadual de São Paulo

    NASA Astrophysics Data System (ADS)

    de Oliveria, E. F.; Voelzke, M. R.

    2009-03-01

    Sendo a Astronomia uma das cièncias mais antigas da humanidade, e considerando sua importáncia histórica e cultural, é de extrema releváncia que tópicos relacionados a ela sejam tratados nas escolas. Embora os Parámetros Curriculares Nacionais do Ensino Médio (PCN-EM) e as Orientaçiacute;es Complementares aos Parámetros (PCN+) apontem a importáncia de uma abordagem significativa de conceitos relacionados à Astronomia nas aulas de Física, muitos estudantes terminam o Ensino Médio (EM) sem compreender a razão de certos acontecimentos de origem celeste, ainda que estes façam parte de seu cotidiano e sejam alvos da curiosidade natural dos jovens. Da observação dessa curiosidade em alunos de uma escola pública paulista, na cidade de Suzano, surgiu o interesse em investigar os conhecimentos básicos em Astronomia dos alunos do Ensino Médio desta escola, constituindo-se este como principal objetivo desta pesquisa. Para tanto foi elaborado um questionário de múltipla escolha aplicado inicialmente a 34 alunos do primeiro ano e, posteriormente, a mais 310, distribuídos entre as très séries do Ensino Médio dos períodos matutino e noturno. Dessa forma, observou-se que 73,9% dos estudantes identificaram o Sol como sendo uma estrela, 67,1% mostraram compreender a sucessão entre dia e noite e 52,3% relacionaram o Big Bang à origem do Universo. Em contrapartida, apenas 34,5% relacionaram as estaçíes do ano à inclinação do eixo de rotação da Terra, 21,3% indicaram a influència gravitacional simultánea da Lua e do Sol como responsável pelo fenòmeno das marés, 24,5% indicaram corretamente quais são os objetos celestes mais próximos da Terra, 36,1% identificaram ano-luz como uma medida de distáncia e 34,2% reconheceram as estrelas cadentes como meteoros, evidenciando-se assim o pequeno discernimento dos estudantes quanto aos fenòmenos e termos astronòmicos do cotidiano. Além disso, foram comparadas as respostas de alun! os de diferentes s

  12. Abundâncias em estrelas de Bário

    NASA Astrophysics Data System (ADS)

    Allen, D. M.

    2003-08-01

    Estrelas de Bário apresentam linhas intensas de elementos produzidos pelo processos (ex: Ba, Y, Sr, Zr) e bandas intensas de CN, C2 e CH. A hipótese mais aceita sobre a origem deste grupo peculiar é a de que essas estrelas façam parte de sistemas binários, tendo recebido material enriquecido em elementos pesados da companheira mais evoluída. Apresentamos neste trabalho uma análise detalhada de uma amostra de estrelas desta classe, incluindo determinação de parâmetros atmosféricos e cálculo de abundâncias. As temperaturas efetivas foram determinadas a partir de dados fotométricos obtidos com o Fotrap instalado no telescópio Zeiss do LNA (Laboratório Nacional de Astrofísica) (B-V, V-I, R-I, V-R), e coletados na literatura nos catálogos Hipparcos (B-V), 2MASS (Two Micron All Sky Survey) (V-K) e The General Catalogue Photometric Data (sistema Geneva). Obtivemos uma faixa de temperaturas de 4400 £ Tef £ 6500. As metalicidades foram determinadas a partir de linhas de Fe I e Fe II, estando os resultados no intervalo -1 £ [Fe/H] £ +0.1. O log g foi determinado pelo equilíbrio de ionização e pela relação com a magnitude bolométrica, a temperatura e a massa, sendo os resultados na faixa 1.5 £ log g £ 4.5. As distâncias utilizadas foram determinadas com o auxílio das paralaxes Hipparcos, e as massas determinadas por modelos de isócronas. Os espectros utilizados foram obtidos com o espectrógrafo FEROS no Telescópio de 1,5m do ESO (European Southern Observatory). As abundâncias foram calculadas por meio de síntese espectral de linhas individuais incluindo elementos alfa, pico do Fe, s e r. Encontramos um excesso de elementos pesados em relação ao Fe, como esperado para estrelas de Bário.

  13. Identified EM Earthquake Precursors

    NASA Astrophysics Data System (ADS)

    Jones, Kenneth, II; Saxton, Patrick

    2014-05-01

    Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After a number of custom rock experiments, two hypotheses were formed which could answer the EM wave model. The first hypothesis concerned a sufficient and continuous electron movement either by surface or penetrative flow, and the second regarded a novel approach to radio transmission. Electron flow along fracture surfaces was determined to be inadequate in creating strong EM fields, because rock has a very high electrical resistance making it a high quality insulator. Penetrative flow could not be corroborated as well, because it was discovered that rock was absorbing and confining electrons to a very thin skin depth. Radio wave transmission and detection worked with every single test administered. This hypothesis was reviewed for propagating, long-wave generation with sufficient amplitude, and the capability of penetrating solid rock. Additionally, fracture spaces, either air or ion-filled, can facilitate this concept from great depths and allow for surficial detection. A few propagating precursor signals have been detected in the field occurring with associated phases using custom-built loop antennae. Field testing was conducted in Southern California from 2006-2011, and outside the NE Texas town of Timpson in February, 2013. The antennae have mobility and observations were noted for

  14. Recent developments on SU UMa stars - theory vs. observation

    NASA Astrophysics Data System (ADS)

    Cannizzo, John K.

    2015-01-01

    Kepler light curves of short period dwarf novae have resparked interest in the nature of superoutbursts and led to the question: Is the thermal-tidal instability needed, or can the plain vanilla version of the accretion disk limit cycle do the job all by itself? A detailed time-resolved study of an eclipsing SU UMa system during superoutburst onset should settle the question - if there is a dramatic contraction of the disk at superoutburst onset, Osaki's thermal-tidal model would be preferred; if not, the plain disk instability model would be sufficient. I will present recent results that support the contention by Osaki & Kato that the time varying negative superhump frequencies can be taken as a surrogate for the outer disk radius variations. Finally, it may be necessaryto look beyond the short period dwarf novae to gain perspective on the nature of embedded precursors in long outbursts.

  15. Learner Responses to the Use of Television in UMA Courses. Working Paper No. 8.

    ERIC Educational Resources Information Center

    Brown, Laurence A.

    The purpose of this paper is to present and discuss learner responses to the television component of the various courses developed or offered by the University of Mid-America (UMA). Implications for courseware development are outlined, and research questions to be addressed are suggested. Four courses were offered by UMA: (1) Accounting I, (2)…

  16. Estudo de soluções locais e cosmológicas em teorias do tipo tensor-escalar

    NASA Astrophysics Data System (ADS)

    Silva E Costa, S.

    2003-08-01

    Teorias do tipo tensor-escalar são a mais simples extensão possí vel da Relatividade Geral. Nessas teorias, cujo modelo padrão é a teoria de Brans-Dicke, a curvatura do espaço-tempo, descrita por componentes tensoriais, aparece acoplada a um campo escalar que, de certo modo, representa uma variação na constante de acoplamento da gravitação. Tais teorias apresentam soluções locais e cosmológicas que, em determinados limites, recaem nas apresentadas pela Relatividade Geral, mas que em outros limites trazem novidades, tais como conseqüências observacionais da evolução de flutuações primordiais distintas daquelas previstas pela Relatividade Geral (ver, por ex., Nagata et al., PRD 66, p. 103510 (2002)). Graças a esta possibilidade de trazer à luz novidades em relação à gravitação, teorias do tipo tensor-escalar podem ser vistas como um interessante campo alternativo de pesquisas para soluções dos problemas de massa faltante (ou escura) e/ou energia escura. Seguindo tal linha, este trabalho, ainda em sua fase inicial, apresenta soluções gerais de teorias do tipo tensor-escalar para diversas situações, verificando-se em que consiste a divergência dessas soluções dos casos tradicionais possí veis na Relatividade Geral. Como exemplos das soluções aqui apresentadas pode-se destacar uma expressão geral para diferentes soluções cosmológicas englobando diferentes tipos de matéria (representados por diferentes equações de estado), e a expressão para uma solução local representando um buraco negro com rotação, similar à solução de Kerr da Relatividade Geral. Por fim, é importante ressaltar que, embora aqui apresentem-se poucos resultados novos, na literatura sobre o assunto a maior parte das soluções apresentadas limita-se a uns poucos casos especí ficos, tal como soluções cosmológicas apenas com curvatura nula, e que mesmo as soluções disponí veis são, em geral, pouco divulgadas e, portanto, pouco conhecidas, e

  17. Evolução química em galáxias compactas azuis (BCGs)

    NASA Astrophysics Data System (ADS)

    Lanfranchi, G. A.; Matteucci, F.

    2003-08-01

    Neste trabalho, a formação estelar e evolução quí mica em galáxias Compactas Azuis (Blue Compact Galaxies - BCGs) foram estudadas através da comparação de previsões de modelos de evolução quí mica a várias razões de abundância quí mica observadas nestas galáxias. Modelos detalhados com recentes dados de nucleossí ntese e que levam em consideração o papel desempenahdo por supernovas de ambos os tipos (II e Ia) na evolução galáctica foram desenvolvidos para as BCGs permitindo seguir a evolução de vários elementos quí micos (H, D, He, C, N, O, Mg, Si, S, Ca, e Fe). O modelo é caracterizado pelas prescrições adotadas para a formação estelar, a qual ocorre em vários surtos de atividade separados por longos perí odos quiescentes. Após ajustar os melhores modelos aos dados observacionais, as previsões destes modelos foram comparadas também a razões de abundância observadas em sistemas Damped Lyman alpha (DLAs) e a origem do N (primária ou secundária) foi discutida. Alguns dos resultados obtidos são: i) as razões de abundância observadas nas BCGs são reproduzidas por modelos com 2 a 7 surtos de formação estelar com eficiência entre n = 0.2-0.9 Gano-1; ii) os baixos valores de N/O observados nestas galáxias são um resultado natural de uma formação estelar em surtos; iii) os modelos para BCGs podem reproduzir os dados dos DLAs, iv) uma quantidade "baixa" de N primário produzido em estrelas de alta massa pode ser uma explicação para os baixos valores de [N/a] observados em DLAs.

  18. Perda de massa em ventos empoeirados de estrelas supergigantes

    NASA Astrophysics Data System (ADS)

    Vidotto, A. A.; Jatenco-Pereira, V.

    2003-08-01

    Em praticamente todas as regiões do diagrama HR, as estrelas apresentam evidências observacionais de perda de massa. Na literatura, pode-se encontrar trabalhos que tratam tanto do diagnóstico da perda de massa como da construção de modelos que visam explicá-la. O amortecimento de ondas Alfvén tem sido utilizado como mecanismo de aceleração de ventos homogêneos. Entretanto, sabe-se que os envelopes de estrelas frias contêm grãos sólidos e moléculas. Com o intuito de estudar a interação entre as ondas Alfvén e a poeira e a sua conseqüência na aceleração do vento estelar, Falceta-Gonçalves & Jatenco-Pereira (2002) desenvolveram um modelo de perda de massa para estrelas supergigantes. Neste trabalho, apresentamos um estudo do modelo acima proposto para avaliar a dependência da taxa de perda de massa com alguns parâmetros iniciais como, por exemplo, a densidade r0, o campo magnético B0, o comprimento de amortecimento da onda L0, seu fluxo f0, entre outros. Sendo assim, aumentando f0 de 10% a partir de valores de referência, vimos que aumenta consideravelmente, enquanto que um aumento de mesmo valor em r0, B0 e L0 acarreta uma diminuição em .

  19. Rotação do jato em DG tau próximo à região de sua formação: análise comparativa das velocidades radiais simuladas e observadas

    NASA Astrophysics Data System (ADS)

    Cerqueira, A. H.; de Gouveia dal Pino, E. M.

    2003-08-01

    Os modelos magneto-centrífugos utilizados para explicar a formação dos jatos Herbig-Haro assumem a presença de um disco de acresção em rotação kepleriana na base de lançamento do jato. Neste cenário, o jato transmite a informação da rotação do disco para regiões distantes da fonte central, além da superfície de Alfvén, na região de colimação inicial do jato. Recentemente, Bacciotti et al. (2002, ApJ, 537, L49) obtiveram pela primeira vez uma evidência observacional de rotação em um jato HH, o jato em DG Tau, em regiões próximas da fonte central, compatível (qualitativa e quantitativamente) com o esperado a partir dos modelos magneto-centrífugos para a produção e colimação inicial de jatos HH. No presente trabalho, apresentamos mapas de velocidade radial, obtidos através de simulações numéricas tri-dimensionais SPH, para um jato com características semelhantes ao jato em DG Tau, objetivando uma comparação com os mapas de velocidade radiais obtidos por Bacciotti et al.. Nossos resultados, embora preliminares, indicam que a inclusão de efeitos como a precessão, evidenciada em DG Tau (Dougados et al. 2000, A&A, 357, L61) devem ser levadas em consideração na análise da presença de rotação não só em DG Tau mas em qualquer sistema, com o uso das velocidades radias observadas. A ausência de um grau elevado de simetria axial (quebrada, por exemplo, pela precessão do eixo do jato; ou pela presença de uma superfície interna de trabalho, ou seja, um bow shock interno), implica também em uma maior complexidade nos mapas, com conseqüências relevantes para suas interpretações.

  20. EPA LABORATORIES IMPLEMENT EMS PROGRAM

    EPA Science Inventory

    This paper highlights the breadth and magnitude of carrying out an effective Environmental Management System (EMS) program at the U.S. EPA's research and development laboratories. Federal research laboratories have unique operating challenges compared to more centralized industr...

  1. Análise da medição do raio solar em ultravioleta

    NASA Astrophysics Data System (ADS)

    Saraiva, A. C. V.; Giménez de Castro, C. G.; Costa, J. E. R.; Selhorst, C. L.; Simões, P. J. A.

    2003-08-01

    A medição acurada do raio solar em qualquer banda do espectro eletromagnético é de relevância na formulação e calibração de modelos da estrutura e atmosfera solar. Esses modelos atribuem emissão do contínuo do Sol calmo em microondas à mesma região da linha Ha do Hell. Apresentamos a medição do raio solar em UV com imagens do EIT (Extreme Ultraviolet Image Telescope) entre 1996 e 2002, no comprimento de onda 30,9 nm (Ha do Hell), que se forma na região de transição/cromosfera solar. A técnica utilizada para o cálculo do raio UV foi baseada na transformada Wavelet B3spline. Fizemos um banco de dados com 1 imagem por dia durante o período citado. Obtivemos como resultado o raio médio da ordem de 975.61" e uma diminuição do mesmo para o período citado variando em média -0,45" /ano. Comparamos estes dados com os valores obtidos pelo ROI (Radio Observatório de Itapetinga) em 22/48 GHz e Nobeyama Radio Heliograph em 17 GHz mostrando que os raios médios são muito próximos o que indica que a região de formação nessas freqüências é a mesma conforme os modelos. Comparamos os resultados também com outros índices de atividade solar.

  2. VizieR Online Data Catalog: Galaxies in the UMa cluster complex (Karachentsev+, 2013)

    NASA Astrophysics Data System (ADS)

    Karachentsev, I. D.; Nasonova, O. G.; Courtois, H. M.

    2015-04-01

    A nearby friable cloud in Ursa Majoris contains 270 galaxies with radial velocities 500UMa complex. According to Makarov & Karachentsev (2011MNRAS.412.2498M, Cat. J/MNRAS/412/2498), most of the UMa galaxies belong to seven bound groups, which have the following median parameters: velocity dispersion of 58k/s, harmonic projected radius of 300kpc, virial mass of 2x1012M⊙ and virial mass-to-K-band luminosity ratio of 27M⊙/L⊙. Almost a half of the UMa cloud population are gas-rich dwarfs (Ir, Im, BCD) with active star formation seen in the GALEX UV-survey. The UMa groups reside within 15-19Mpc from us, being just at the same distance as the Virgo cluster. The total virial mass of the UMa groups is 4x1013M⊙, yielding the average density of dark matter in the UMa cloud to be Ωm=0.08, i.e. a factor of 3 lower than the cosmic average. This is despite the fact that the UMa cloud resides in a region of the Universe that is an apparent overdensity. A possible explanation for this is that most mass in the Universe lies in the empty space between clusters. Herewith, the mean distances and velocities of the UMa groups follow nearly undisturbed Hubble flow without a sign of the 'Z-wave' effect caused by infall towards a massive attractor. This constrains the total amount of dark matter between the UMa groups within the cloud volume. (1 data file).

  3. Uma Visão do Universo Segundo um Grupo de Alunos do Ensino Médio de São Paulo

    NASA Astrophysics Data System (ADS)

    Elias, D. S.; Araújo, M.; Amaral, L. H.; Voelzke, M. R.; Araújo, M.

    2005-08-01

    A astronomia, embora seja uma ciência popular, com inúmeras descobertas de interesse público, ainda é apresentada desconsiderando-se os aspectos históricos e científicos relacionados ao seu desenvolvimento, sendo geralmente veiculada nos meios de comunicação de maneira pouco esclarecedora e não raro com imprecisões. Neste trabalho analisou-se a concepção de um grupo de estudantes de Ensino Médio sobre conceitos de astronomia, visando identificar sua visão de mundo a respeito do Universo, envolvendo idéias sobre espaço e tempo. Para issso, foi aplicado um questionário em três escolas da grande São Paulo em um espaço amostral de 270 alunos. Constatou-se que, embora o ensino de astronomia esteja previsto nos PCNEM, os resultados obtidos na pesquisa mostram que há grande deficiência no conhecimento dos temas investigados. Nesse sentido, verificou-se que apenas 20% dos alunos eram capazes de relacionar a sucessão das semanas com as fases da lua, enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra. Por outro lado, somente 23% dos alunos tinham noções das distâncias entre os objetos celestes próximos da Terra e 56% conseguiram relacionar o Big Bang com a origem do Universo. Finalmente, constatou-se que 37% reconheciam o ano-luz como uma unidade de distância e 60% reconheciam o Sol como sendo uma estrela. Apesar de 60% dos alunos indicarem que a escola é a principal fonte para aquisição dos conhecimentos de astronomia, conclui-se que seus conceitos nessa área ainda são inadequados, havendo necessidade de ampliação e aprimoramento da abordagem desses conteúdos nos ambientes escolares.

  4. Observações no infravermelho médio de objetos estelares jovens em NGC 3576

    NASA Astrophysics Data System (ADS)

    Barbosa, C.; Damineli, A.; Blum, R.; Conti, P.

    2003-08-01

    Apresentamos os resultados de observações no infravermelho médio de candidatos a objetos estelares jovens e massivos em NGC 3576. As imagens de alta resolução foram obtidas no observatório Gemini Sul com o uso dos filtros em 10,8, 7,9, 9,8, 12,5 e 18,2 mm. Nossas imagens mostram a fonte IRS 1 resolvida em 4 objetos pela primeira vez em 10 mm. Para cada objeto obtivemos a distribuição espectral de energia de 1.2 até 18 mm, bem como a temperatura de cor, a distribuição espacial e a profundidade óptica em 9,8 mm da poeira circunstelar. Apresentamos uma estimativa das massas dos objetos estudados, baseados na luminosidade emitida no infravermelho médio, bem como um modelo para explicar as diferentes características observadas de cada objeto. Finalmente discutimos a possível localização da(s) fonte(s) de ionização de NGC 3576.

  5. New Light Curves and Period Studies of V502 OPH W UMA System

    NASA Astrophysics Data System (ADS)

    Awadalla, Nabil S.

    NEW LIGHT CURVES AND PERIOD STUDIES OF V502 OPH W UMa SYSTEM N.S.Awadalla National Research Institute of Astronomy and Geophysics( NRIAG ) Helwan Cairo EGYPT New BVR photoelectric observations of the W UMa eclipsing binary system V502 Oph have been presented and analyzed. The geometric and physical elements of the system have been obtained and compared to the previous results. The classification of the system concerning the sub-type of the W UMa binary has been studied as well as its evolution stage. Its period variation in a view of the light time effect has been examin

  6. Fundamental data for contact binaries: RZ Comae, RZ Tauri, and AW UMa

    NASA Technical Reports Server (NTRS)

    Wilson, R. E.; Devinney, E. J.

    1972-01-01

    Differential corrections analyses of three W UMa type binaries show that RZ Tau and AW UMa have common envelopes and the relatively small gravity darkening predicted by Lucy, while RZ Comae seems to have a larger gravity effect and is only marginally in contact. Some details of the method for computing contact binary light curves are given. It is suggested that W UMa binaries which have occultation primary eclipses may, in general, have large amplitudes for gravity darkening or a photometric surface brightness effect which simulates large gravity darkening.

  7. Código para imageamento indireto de estrelas em sistemas binarios: simulação de variações elipsoidais e do perfil das linhas

    NASA Astrophysics Data System (ADS)

    Souza, T. R.; Baptista, R.

    2003-08-01

    As estrelas secundárias em variáveis cataclí smicas (VCs) e binárias-x de baixa massa (BXBMs) são cruciais para o entendimento da origem, evolução e comportamento destas binárias interagentes. Elas são estrelas magneticamente ativas submetidas a condições ambientais extremas [e.g., estão muito próximas de uma fonte quente e irradiante; têm rotação extremamente rápida e forma distorcida; estão perdendo massa a taxas de 10-8-10-10 M¤/ano] que contribuem para que suas propriedades sejam distintas das de estrelas de mesma massa na seqüência principal. Por outro lado, o padrão de irradiação na face da secundária fornece informação sobre a geometria das estruturas de acréscimo em torno da estrela primária. Assim, a obtenção de imagens da superfície destas estrelas é de grande interesse astrofísico. A Tomografia Roche usa as variações no perfil das linhas de emissão/absorção da estrela secundária em função da fase orbital para mapear a distribuição de brilho em sua superfície. Neste trabalho apresentamos os resultados iniciais do desenvolvimento de um programa para o mapeamento da distribuição de brilho na superfí cie das estrelas secundárias em VCs e BXBMs com técnicas de astro-tomografia. Presentemente temos em operação um código que simula as variações no perfil das linhas em conseqüência de efeito Doppler resultante da combinação de rotação e translação de uma estrela em forma de lobo de Roche em torno do centro de massa da binária, em função da distribuição de brilho na superfície desta estrela. O código igualmente produz a curva de luz resultante das variações de aspecto da estrela em função da fase orbital (variações elipsoidais).

  8. SPECTROSCOPIC METALLICITY DETERMINATIONS FOR W UMa-TYPE BINARY STARS

    SciTech Connect

    Rucinski, Slavek M.; Pribulla, Theodor; Budaj, Jan E-mail: pribulla@ta3.sk

    2013-09-15

    This study is the first attempt to determine the metallicities of W UMa-type binary stars using spectroscopy. We analyzed about 4500 spectra collected at the David Dunlap Observatory. To circumvent problems caused by the extreme spectral line broadening and blending and by the relatively low quality of the data, all spectra were subject to the same broadening function (BF) processing to determine the combined line strength in the spectral window centered on the Mg I triplet between 5080 A and 5285 A. All individual integrated BFs were subsequently orbital-phase averaged to derive a single line-strength indicator for each star. The star sample was limited to 90 W UMa-type (EW) binaries with the strict phase-constancy of colors and without spectral contamination by spectroscopic companions. The best defined results were obtained for an F-type sub-sample (0.32 < (B - V){sub 0} < 0.62) of 52 binaries for which integrated BF strengths could be interpolated in the model atmosphere predictions. The logarithmic relative metallicities, [M/H], for the F-type sub-sample indicate metal abundances roughly similar to the solar metallicity, but with a large scatter which is partly due to combined random and systematic errors. Because of the occurrence of a systematic color trend resulting from inherent limitations in our approach, we were forced to set the absolute scale of metallicities to correspond to that derived from the m{sub 1} index of the Stroemgren uvby photometry for 24 binaries of the F-type sub-sample. The trend-adjusted metallicities [M/H]{sub 1} are distributed within -0.65 < [M/H]{sub 1} < +0.50, with the spread reflecting genuine metallicity differences between stars. One half of the F-sub-sample binaries have [M/H]{sub 1} within -0.37 < [M/H]{sub 1} < +0.10, a median of -0.04 and a mean of -0.10, with a tail toward low metallicities, and a possible bias against very high metallicities. A parallel study of kinematic data, utilizing the most reliable and recently

  9. Spectroscopic Metallicity Determinations for W UMa-type Binary Stars

    NASA Astrophysics Data System (ADS)

    Rucinski, Slavek M.; Pribulla, Theodor; Budaj, Ján

    2013-09-01

    This study is the first attempt to determine the metallicities of W UMa-type binary stars using spectroscopy. We analyzed about 4500 spectra collected at the David Dunlap Observatory. To circumvent problems caused by the extreme spectral line broadening and blending and by the relatively low quality of the data, all spectra were subject to the same broadening function (BF) processing to determine the combined line strength in the spectral window centered on the Mg I triplet between 5080 Å and 5285 Å. All individual integrated BFs were subsequently orbital-phase averaged to derive a single line-strength indicator for each star. The star sample was limited to 90 W UMa-type (EW) binaries with the strict phase-constancy of colors and without spectral contamination by spectroscopic companions. The best defined results were obtained for an F-type sub-sample (0.32 < (B - V)0 < 0.62) of 52 binaries for which integrated BF strengths could be interpolated in the model atmosphere predictions. The logarithmic relative metallicities, [M/H], for the F-type sub-sample indicate metal abundances roughly similar to the solar metallicity, but with a large scatter which is partly due to combined random and systematic errors. Because of the occurrence of a systematic color trend resulting from inherent limitations in our approach, we were forced to set the absolute scale of metallicities to correspond to that derived from the m 1 index of the Strömgren uvby photometry for 24 binaries of the F-type sub-sample. The trend-adjusted metallicities [M/H]1 are distributed within -0.65 < [M/H]1 < +0.50, with the spread reflecting genuine metallicity differences between stars. One half of the F-sub-sample binaries have [M/H]1 within -0.37 < [M/H]1 < +0.10, a median of -0.04 and a mean of -0.10, with a tail toward low metallicities, and a possible bias against very high metallicities. A parallel study of kinematic data, utilizing the most reliable and recently obtained proper motion and radial

  10. Is EMS communicating with the FCC?

    PubMed

    Johnson, M S; VanCott, C; Glass, C; Anderson, P B

    1989-07-01

    Radio communication problems in EMS run the spectrum from annoying to deadly. Dedicated radio frequencies for EMS, much like those exclusive to police and fire departments, are long overdue. PMID:10293680

  11. Alveolar Echinococcosis: Characterization of Diagnostic Antigen Em18 and Serological Evaluation of Recombinant Em18

    PubMed Central

    Sako, Yasuhito; Nakao, Minoru; Nakaya, Kazuhiro; Yamasaki, Hiroshi; Gottstein, Bruno; Lightowers, Marshall W.; Schantz, Peter M.; Ito, Akira

    2002-01-01

    The Echinococcus multilocularis protein Em18 is one of the most promising antigens for use in serodiagnosis of alveolar echinococcosis in human patients. Here we identify an antigenic relationship between Em18 and a 65-kDa immunodominant E. multilocularis surface protein previously identified as either EM10 or EmII/3. The NH2-terminal sequence of native Em18 was determined, revealing it to be a fragment of EM10. Experiments were undertaken to investigate the effect of proteinase inhibitors on the degradation of EM10 in crude extracts of E. multilocularis protoscoleces. Em18 was found to be the product of degradation of EM10 by cysteine proteinase. A recombinant Em18 (RecEm18, derived from 349K to 508K of EM10) was successfully expressed by using Escherichia coli expression system and then evaluated for use in serodiagnosis of alveolar echinococcosis. RecEm18 was recognized by 27 (87.1%) and 28 (90.3%) of 31 serum samples from clinically and/or pathologically confirmed alveolar echinococcosis patients by enzyme-linked immunosorbent assay and immunoblotting, respectively. Of 33 serum samples from cystic echinococcosis patients, 1 was recorded as having a weak positive reaction to RecEm18; however, none of the serum samples which were tested from neurocysticercosis patients (n = 10) or healthy people (n = 15) showed positive reactions. RecEm18 has the potential for use in the differential serodiagnosis of alveolar echinococcosis. PMID:12149326

  12. The European Mobile System (EMS)

    NASA Technical Reports Server (NTRS)

    Jongejans, A.; Rogard, R.; Mistretta, I.; Ananasso, F.

    1993-01-01

    The European Space Agency is presently procuring an L band payload in order to promote a regional European L band system coping with the specific needs of the European market. The payload, and the two communications systems to be supported, are described below. The potential market for EMS in Europe is discussed.

  13. Influência da presença de endossimbionte em Brevipalpus phoenicis na aquisição e transmissão do vírus da leprose dos citros.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A leprose dos citros destaca-se como uma fitovirose de grande impacto econômico e ambiental à citricultura, elevando o custo de produção para o controle do vetor B. phoenicis. É conhecido que a presença de endossimbiontes do gênero Cardinium em ácaros Brevipalpus spp. causa a feminilização dos ácaro...

  14. Radial velocity mapping of Paczyński's star AW UMa: not a contact binary

    NASA Astrophysics Data System (ADS)

    Pribulla, T.; Rucinski, S. M.

    2008-05-01

    We present 2D (radial velocity, orbital phase) spectroscopic results for the very low mass-ratio close binary AW UMa which strongly indicate that the spectroscopic mass ratio (qsp = 0.10) does not agree with the photometrically derived one and that the widely adopted contact binary model appears to experience serious inconsistencies and limitations for this object. AW UMa is compared with V566 Oph (qsp = 0.26) which we found to behave according to the contact model. Observed broadening functions of AW UMa can be interpreted by a very strong limb darkening and/or non-solid-body rotation of the dominant primary component; the former assumption is unphysical while the differential rotation is not supported by an apparent stability of localized, dark features on the outer side of the primary. There are indications of the existence of an equatorial belt encompassing the whole system. All deficiencies in the interpretation and the discrepancy between the photometric and spectroscopic mass ratio of AW UMa can be solved within a new model of AW UMa where both components are detached and the system is submerged in a stream of hot, optically thick matter which mimics the stellar contact. While the masses and their ratio are correctly given by spectroscopy, the photometric picture is heavily modified by the matter engulfing both stars in the equatorial plane. Based on the data obtained at the David Dunlap Observatory, University of Toronto. E-mail: pribulla@ta3.sk (TP); rucinski@astro.utoronto.ca (SMR)

  15. Elemental Abundance Analyses with DAO Spectrograms. XXXIX. The Am Stars 2 UMa and 15 Vul

    NASA Astrophysics Data System (ADS)

    Çay, İpek H.; Teker Yelkenci, Aysegul; Adelman, Saul J.

    2016-05-01

    We derived the elemental abundances of the metallic-line stars 2 UMa (=HR 3354; spectral type A2m) and 15 Vul (=HR 7653; spectral type A4 III), using high-dispersion, high signal-to-noise ratio (≥200) optical region spectrograms obtained with CCD detectors at the long Coudé camera of the 1.22 m telescope of the Dominion Astrophysical Observatory (DAO) and Kurucz's ATLAS9 and WIDTH9 programs. The star 2 UMa has not been the subject of a modern detailed elemental abundances analysis. It is relatively sharp-lined and sufficiently hot (T eff = 8050 K) that the continuum placement is not a major problem in the optical region. Comparison of the results of this new study of 15 Vul with the last complete study shows a 0.15 dex mean increase in the derived abundances and a reduction in the standard deviations of the mean values. The abundance anomalies of 2 UMa are usually larger than those of 15 Vul. The greater spectral coverage of 15 Vul compared with 2 UMa results in a larger number of abundances being derived. The abundances of 2 UMa are typical for those of classical Am stars that have similar effective temperatures and surface gravities. 15 Vul, characterized by a similar effective temperature and smaller surface gravity, is a more evolved star.

  16. Transmission electron microscopic observations on ultrastructural alterations in Schistosoma mansoni adult worms recovered from C57BL/6 mice treated with radiation-attenuated vaccine and/or praziquantel in addition to passive immunization with normal and vaccinated rabbit sera against infection.

    PubMed

    El-Shabasy, Eman A; Reda, Enayat S; Abdeen, Sherif H; Said, Ashraf E; Ouhtit, Allal

    2015-04-01

    Although the current treatment of schistosomiasis relies largely on praziquantel (PZQ), it has not been successful in significantly reducing the overall rate of disease cases, one of the suggested reasons being the inevitable resistance to PZQ. Previous studies showed that radiation-attenuated vaccine provides protection against Schistosoma mansoni in a host of various species. In the present study, we evaluated the effect of various vaccination strategies in C57BL/6 mice, including single or multiple vaccination strategy, subcurative dose (20 mg/kg) of PZQ, and a combination of single vaccination with subcurative dose of PZQ. Treatment either with subcurative dose of PZQ or with a single vaccination of attenuated cercariae (500 per mouse), caused significant reduction in total worm burden, hepatic, and intestinal ova counts of 43.03, 73.2, and 59.5 and 37.97, 52.02, and 26.3%, respectively. Furthermore, tegumental changes were observed. In multiple vaccinated group, there was an extensive lysis in tegumental layers. High deformations in gastrodermis, testis cells, vitelline cells, and oocytes were recorded. Also, this study is to explore the role of humoral immunity using highly resistant rabbits that had been exposed to three immunizations with ultraviolet (UV)-irradiated cercariae (8000 per rabbit in each immunization), and their sera were tested for their ability to transfer protection. The reduction in challenge worm burden had reached 32.76-43.64% when compared with recipients of normal serum or no serum. The reduction in hepatic and intestinal ova counts reached to 74.4 and 71.08% in group immunized with vaccinated rabbit sera. Swelling and extensive lysis of tegumental layers, gastrodermis lumen, spermatocytes, and deformation of oocytes were recorded with more severity than that recorded in normal rabbit sera group. Our findings recorded that multiple vaccination strategy is the most effective strategy then passive transfer of vaccinated rabbit. This gives

  17. População nuclear e extranuclear em rádio-galáxias

    NASA Astrophysics Data System (ADS)

    Raimann, D. I.; Storchi-Bergmann, T.; Quintana, H.; Alloin, D.; Hunstead, R.; Wisotzki, L.

    2003-08-01

    A natureza do contínuo UV/ótico em rádio-galáxias é muito importante para o seu entendimento. Em baixos redshifts existem evidências de que muitas delas são dominadas no ótico por luz de estrelas velhas, características de galáxias early-type e em altos redshifts a característica dominante é um excesso de luz no UV, freqüentemente associado com estruturas que estão alinhadas aos eixos das estruturas rádio em grande escala. Inicialmente esse excesso foi interpretado como devido a episódios intensos de formação estelar nas galáxias hospedeiras. Entretanto, as descobertas dos alinhamentos entre as estruturas UV e rádio modificaram essa idéia. Foi proposto que a formação estelar é iniciada pela passagem do jato rádio através do meio interestelar das galáxias hospedeiras. A natureza do excesso UV começou a ser compreendida em um estudo detalhado do continuo ótico da 3C321, onde se concluiu que o contínuo desta galáxia tem origem multicomponente, com contribuições de populações velhas e intermediárias, de luz espalhada oriunda de um quasar obscurecido e do contínuo nebular. No presente trabalho estudamos a população nuclear e extranuclear de uma amostra de 24 rádio-galáxias, utilizando espectros óticos de fenda longa, com alta razão sinal/ruído. Através do método de síntese espectral de populações estelares, foram estimadas as contribuições de populações estelares de diferentes idades (e de um contínuo tipo lei de potência devido a um AGN, FC) para a luz integrada das galáxias, em 4020Å. As principais conclusões deste trabalho são: apenas quatro dos objetos estudados têm contribuições significativas (maiores do que 10%) das populações de 100 milhões de anos ou mais jovens (ou de FC) ao longo da região espacial estudada (6 kpc centrais); nenhuma das rádio-galáxias de tipo FRI estudadas tem contribuição significativa destas populações ao longo desta região; duas (de oito) de tipo FRII tem contribui

  18. High-frequency variations of hydrogen spectral lines in the B3V star η UMa

    NASA Astrophysics Data System (ADS)

    Pokhvala, S. M.

    2015-09-01

    We reported the detection of high-frequency variations in the hydrogen Balmer lines in the hot star η UMa of spectral class B3V. Spectral observations of η UMa were carried out with slitless spectrograph (R˜100) installed on the 60 cm Carl Zeiss telescope in the Andrushivka Observatory. Spectra were obtained with a time resolution in the sub-second range. It has been found that the η UMa shows rapid variations in the hydrogen lines Hα, Hβ, Hγ, as well as variations in the atmospheric oxygen lines. The intensity variations in the hydrogen lines varies from 0.2% to 0.5% , and that of the oxygen lines is approximately 2%.

  19. Ensino de gravitação clássica no nível médio: uma proposta de abordagem e resultados preliminares

    NASA Astrophysics Data System (ADS)

    Medeiros, G. C. M.; Jafelice, L. C.

    2003-08-01

    O ensino de gravitação clássica é comumente realizado de maneira formal e descontextualizado da experiência com a força-peso e da história do tema. Fustigados por anos de experiência de ensino no assunto, nem sempre com bons resultados, propomos uma abordagem ancorada nos eixos: a) contextualização histórica; e b) reconhecimento do peso como a força de atração gravitacional. O primeiro eixo integra o tema no desenvolvimento cultural do ser humano, praticando a interdisciplinaridade. O segundo eixo embasa construtivamente a abordagem, levando o aluno a realizar experiências e a vivenciar o reconhecimento de uma força universal. A abordagem foi construída através das etapas: 1) análise crítica do tema em livros didáticos; 2) elaboração de um curso para professores das várias disciplinas do ensino médio, identificando conexões para a prática da interdisciplinaridade; 3) elaboração de material didático; e 4) avaliação da eficácia da abordagem. No trabalho discutimos em detalhe as quatro etapas. Como resultados, adiantamos que: tabulamos a abordagem de gravitação nos livros didáticos, ainda muito tradicional e carecedora de atividades criativas que poderiam melhor explorar esse assunto; mapeamos, junto aos professores, padrões de conceitos espontâneos e erros associados ao tema; e, no curso, adaptamos e testamos a eficiência de materiais instrucionais existentes e criamos outros novos (e.g., para trabalhar excentricidades das órbitas planetárias), além disto elaboramos roteiros e figuras para tratamentos qualitativo e quantitativo da lei da gravitação universal. As avaliações feitas pelos professores foram muito animadoras. O espaço da presente reunião será aproveitado para socializar a proposta e os resultados obtidos e para submeter o projeto à análise crítica. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP)

  20. FUSE Observations of the Bright, Eclipsing Nova-like Cataclysmic Variable, UX UMa (FUSE 2000)

    NASA Technical Reports Server (NTRS)

    Long, Knox; Froning, Cynthia

    2004-01-01

    This was a project to study the disk and wind of the eclipsing nova-like variable UX UMa, in order to better define the wind geometry of the system, including the nature of the transition region between the disk photosphere and the supersonic wind. We proposed to use phase resolved spectroscopy of the system, taking advantage of the fact that UX UMa is an eclipsing system, to isolate different regions of the wind and to use a Monte Carlo radiative transfer code to simulate the spectra through the eclipse.

  1. DOE/EM Criticality Safety Needs Assessment

    SciTech Connect

    Westfall, Robert Michael; Hopper, Calvin Mitchell

    2011-02-01

    The issue of nuclear criticality safety (NCS) in Department of Energy Environmental Management (DOE/EM) fissionable material operations presents challenges because of the large quantities of material present in the facilities and equipment that are committed to storage and/or material conditioning and dispositioning processes. Given the uncertainty associated with the material and conditions for many DOE/EM fissionable material operations, ensuring safety while maintaining operational efficiency requires the application of the most-effective criticality safety practices. In turn, more-efficient implementation of these practices can be achieved if the best NCS technologies are utilized. In 2002, DOE/EM-1 commissioned a survey of criticality safety technical needs at the major EM sites. These needs were documented in the report Analysis of Nuclear Criticality Safety Technology Supporting the Environmental Management Program, issued May 2002. Subsequent to this study, EM safety management personnel made a commitment to applying the best and latest criticality safety technology, as described by the DOE Nuclear Criticality Safety Program (NCSP). Over the past 7 years, this commitment has enabled the transfer of several new technologies to EM operations. In 2008, it was decided to broaden the basis of the EM NCS needs assessment to include not only current needs for technologies but also NCS operational areas with potential for improvements in controls, analysis, and regulations. A series of NCS workshops has been conducted over the past years, and needs have been identified and addressed by EM staff and contractor personnel. These workshops were organized and conducted by the EM Criticality Safety Program Manager with administrative and technical support by staff at Oak Ridge National Laboratory (ORNL). This report records the progress made in identifying the needs, determining the approaches for addressing these needs, and assimilating new NCS technologies into EM

  2. Genome Sequences of Gordonia Bacteriophages Obliviate, UmaThurman, and Guacamole.

    PubMed

    Pope, Welkin H; Akbar, Armaan F; Ayers, Taylor N; Belohoubek, Selena G; Chung, Connie F; Hartman, Allison C; Kayiti, Tejus; Kessler, Cecilia M; Koman, Philipp I; Kotovskiy, Grigoriy A; Morgan, Taylor M; Rohac, Rebecca M; Silva, Gabriela M; Willis, Charles E; Milliken, Katherine A; Shedlock, Kathleen A; Stanton, Ann-Catherine J; Toner, Chelsea L; Furbee, Emily C; Grubb, Sarah R; Warner, Marcie H; Montgomery, Matthew T; Garlena, Rebecca A; Russell, Daniel A; Jacobs-Sera, Deborah; Hatfull, Graham F

    2016-01-01

    We describe three newly isolated phages-Obliviate, UmaThurman, and Guacamole-that infect Gordonia terrae 3612. The three genomes are related to one another but are not closely related to other previously sequenced phages or prophages. The three phages are predicted to use integration-dependent immunity systems as described in several mycobacteriophages. PMID:27365348

  3. Discovery of a New SU UMa-Type Dwarf Nova, V 1028 Cygni

    NASA Astrophysics Data System (ADS)

    Baba, Hajime; Kato, Taichi; Nogami, Daisaku; Hirata, Ryuko; Matsumoto, Katsura; Sadakane, Kozo

    2000-06-01

    V-band high-speed CCD photometry of V 1028 Cyg revealed that hump structures existed in the early stage of its 1995 July outburst. We obtained 0.06154 (+/- 0.00002) d as the best estimated period of superhumps. We confirmed that this dwarf nova belongs to the SU UMa stars. A re-brightening occurred after the superoutburst, and may be associated with a normal outburst. An analysis of the timings of superhump maxima showed clear evidence for an increase of the superhump period (P_dot = .P/P) with 7.54 x 10-6. Only a few stars (AL Com, T Leo, SW UMa, etc.) are reported to have such an increase of the superhump period. At the end of the superoutburst, we detected that the amplitude of the superhumps increased considerably. Both of these properties are not typical features of ordinary SU UMa stars. The connection between the WZ Sge-type and the SU UMa-type dwarf novae is briefly discussed.

  4. Genome Sequences of Gordonia Bacteriophages Obliviate, UmaThurman, and Guacamole

    PubMed Central

    Akbar, Armaan F.; Ayers, Taylor N.; Belohoubek, Selena G.; Chung, Connie F.; Hartman, Allison C.; Kayiti, Tejus; Kessler, Cecilia M.; Koman, Philipp I.; Kotovskiy, Grigoriy A.; Morgan, Taylor M.; Rohac, Rebecca M.; Silva, Gabriela M.; Willis, Charles E.; Milliken, Katherine A.; Shedlock, Kathleen A.; Stanton, Ann-Catherine J.; Toner, Chelsea L.; Furbee, Emily C.; Grubb, Sarah R.; Warner, Marcie H.; Montgomery, Matthew T.; Garlena, Rebecca A.; Russell, Daniel A.; Jacobs-Sera, Deborah; Hatfull, Graham F.

    2016-01-01

    We describe three newly isolated phages—Obliviate, UmaThurman, and Guacamole—that infect Gordonia terrae 3612. The three genomes are related to one another but are not closely related to other previously sequenced phages or prophages. The three phages are predicted to use integration-dependent immunity systems as described in several mycobacteriophages. PMID:27365348

  5. School Budget Hold'em Facilitator's Guide

    ERIC Educational Resources Information Center

    Education Resource Strategies, 2012

    2012-01-01

    "School Budget Hold'em" is a game designed to help school districts rethink their budgeting process. It evolved out of Education Resource Strategies' (ERS) experience working with large urban districts around the country. "School Budget Hold'em" offers a completely new approach--one that can turn the budgeting process into a long-term visioning…

  6. View of Spacelab engineering Model (EM)

    NASA Technical Reports Server (NTRS)

    1981-01-01

    View of Spacelab engineering Model (EM) as it is being brought in the O and C bldg at Kenndey Space Center (27464); view of the EM as it is being offloaded from the C-54 aircraft. Kennedy Space Center alternative photo number is 108-KSC-80-OC-666 (27465); model taken out to launch pad (27466).

  7. EM international activities. February 1997 highlights

    SciTech Connect

    1997-02-01

    EM International Highlights is a brief summary of on-going international projects within the Department of Energy`s Office of Environmental Management (EM). This document contains sections on: Global Issues, activities in Western Europe, activities in central and Eastern Europe, activities in Russia, activities in Asia and the Pacific Rim, activities in South America, activities in North America, and International Organizations.

  8. Vínculos observacionais para o processo-S em estrelas gigantes de Bário

    NASA Astrophysics Data System (ADS)

    Smiljanic, R. H. S.; Porto de Mello, G. F.; da Silva, L.

    2003-08-01

    Estrelas de bário são gigantes vermelhas de tipo GK que apresentam excessos atmosféricos dos elementos do processo-s. Tais excessos são esperados em estrelas na fase de pulsos térmicos do AGB (TP-AGB). As estrelas de bário são, no entanto, menos massivas e menos luminosas que as estrelas do AGB, assim, não poderiam ter se auto-enriquecido. Seu enriquecimento teria origem em uma estrela companheira, inicialmente mais massiva, que evolui pelo TP-AGB, se auto-enriquece com os elementos do processo-s e transfere material contaminado para a atmosfera da atual estrela de bário. A companheira evolui então para anã branca deixando de ser observada diretamente. As estrelas de bário são, portanto, úteis como testes observacionais para teorias de nucleossíntese pelo processo-s, convecção e perda de massa. Análises detalhadas de abundância com dados de alta qualidade para estes objetos são ainda escassas na literatura. Neste trabalho construímos modelos de atmosferas e, procedendo a uma análise diferencial, determinamos parâmetros atmosféricos e evolutivos de uma amostra de dez gigantes de bário e quatro normais. Determinamos seus padrões de abundância para Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, La, Ce, Nd, Sm, Eu e Gd, concluindo que algumas estrelas classificadas na literatura como gigantes de bário são na verdade gigantes normais. Comparamos dois padrões médios de abundância, para estrelas com grandes excessos e estrelas com excessos moderados, com modelos teóricos de enriquecimento pelo processo-s. Os dois grupos de estrelas são ajustados pelos mesmos parâmetros de exposição de nêutrons. Tal resultado sugere que a ocorrência do fenômeno de bário com diferentes intensidades não se deve a diferentes exposições de nêutrons. Discutimos ainda efeitos nucleossintéticos, ligados ao processo-s, sugeridos na literatura para os elementos Cu, Mn, V e Sc.

  9. Vínculos sobre um modelo de quartessência de Chaplygin usando observações do satélite chandra da fração de massa de gás em aglomerados de galáxias

    NASA Astrophysics Data System (ADS)

    de Souza, R. S.

    2003-08-01

    Observações de Supernovas do tipo Ia mostram que a expansão do Universo está acelerando. Segundo as equações de Einstein uma componente com pressão negativa (energia escura) é necessária para explicar a aceleração cósmica. Além da energia escura é usualmente admitido que no Universo há também uma matéria exótica com pressão zero, que é chamada de matéria escura. Essa componente possui um papel fundamental na formação de estruturas no Universo. Recentemente tem se explorado a possibilidade de que matéria e energia escura poderiam ser unificadas através de uma única componente, que tem sido denominada de quartessência. Um exemplo de fluido com essas características é o Gás de Chaplygin Generalizado, que possui uma equação de estado da forma p = -A/ra. Inicialmente consideramos o caso especial a = 1 (gás de Chaplygin) e vinculamos parâmetros do modelo utilizando observações em raios-X do satélite Chandra da fração de massa de gás em aglomerados de galáxias. Uma comparação dos vínculos obtidos com esse teste com outros testes, tais como supernovas e idade do Universo, mostra que esse teste é bastante restritivo. Exibiremos ainda resultados para o caso em que a curvatura é nula e o parâmetro a está compreendido no intervalo -1 < a 1.

  10. EM International, July 1994, Volume 2

    SciTech Connect

    Not Available

    1994-10-01

    The Office of Environmental Management (EM) at the Department of Energy (DOE) is seeking out and leveraging foreign technology, data, and resources in keeping with EM`s mandate to protect public health and the environment through the safe and cost-effective remediation of the Department`s nuclear weapons sites. EM works closely with foreign governments, industry, and universities to obtain innovative environmental technologies, scientific and engineering expertise, and operations experience that will support EM`s objectives. Where appropriate, these international resources are used to manage the more urgent risks at our sites, secure a safe workplace, help build consensus on critical issues, and strengthen our technology development program. Through international agreements EM engages in cooperative exchange of information, technology, and individuals. Currently, we are managing agreements with a dozen countries in Europe, Latin America, and Asia. These agreements focus on environmental restoration, waste management, transportation of radioactive wastes, and decontamination and decommissioning. This publication contains the following articles: in situ remediation integrated program; in-situ characterization and inspection of tanks; multimedia environmental pollutant assessment system (MEPAS); LLNL wet oxidation -- AEA technology. Besides these articles, this publication covers: EU activities with Russia; technology transfer activities; and international organization activities.

  11. Compilação de dados atômicos e moleculares do UV ao IV próximo para uso em síntese espectral

    NASA Astrophysics Data System (ADS)

    Coelho, P.; Barbuy, B.; Melendez, J.; Allen, D. M.; Castilho, B.

    2003-08-01

    Espectros sintéticos são utéis em uma grande variedade de aplicações, desde análise de abundâncias em espectros estelares de alta resolução ao estudo de populações estelares em espectros integrados. A confiabilidade de um espectro sintético depende do modelo de atmosfera adotado, do código de formação de linhas e da qualidade dos dados atômicos e moleculares que são determinantes no cálculo das opacidades da fotosfera. O nosso grupo no departamento de Astronomia no IAG tem utilizado espectros sintéticos há mais de 15 anos, em aplicações voltadas principalmente para a análise de abundâncias de estrelas G, K e M e populações estelares velhas. Ao longo desse tempo, as listas de linhas vieram sendo construídas e atualizadas continuamente, e alguns acréscimos recentes podem ser citados: Castilho (1999, átomos e moléculas no UV), Schiavon (1998, bandas moleculares de TiO) e Melendez (2001, átomos e moléculas no IV próximo). Com o intuito de calcular uma grade de espectros do UV ao IV próximo para uso no estudo de populações estelares velhas, se fazia necessário compilar e homogeneizar as diversas listas em apenas uma lista atômica e uma molecular. Nesse processo, a nova lista compilada foi correlacionada com outras bases de dados (NIST, Kurucz Database, O' Brian et al. 1991) para atualização dos parâmetros que caracterizam a transição atômica (comprimento de onda, log gf e potencial de excitação). Adicionalmente as constantes de interação C6 foram calculadas segundo a teoria de Anstee & O'Mara (1995) e artigos posteriores. As bandas moleculares de CH e CN foram recalculadas com o programa LIFBASE (Luque & Crosley 1999). Nesse poster estão detalhados os procedimentos citados acima, as comparações entre espectros calculados com as novas listas e espectros observados em alta resolução do Sol e de Arcturus, e uma análise do impacto decorrente da utilização de diferentes modelos de atmosfera no espectro sintético. Ao

  12. Correlação de longo alcance em sistemas binários de raios-x usando remoção de flutuações

    NASA Astrophysics Data System (ADS)

    Pereira, M. G.; Moret, M. A.; Zebende, G. F.; Nogueira, E., Jr.

    2003-08-01

    Neste trabalho é proposta uma metodologia de analise de series temporais de fontes astrofísicas, baseada no método proposto por Peng et al. (1994) e Liu et al. (1999), o qual consiste na idéia de que uma série temporal correlacionada pode ser mapeada por um processo de busca de auto-similaridades em diversas escalas de tempo n. Removendo as eventuais tendências e integrando o sinal observado, é obtida uma medida do desvio médio quadrático das flutuações do sinal integrado F(n)~na, onde a representa o fator de escala associado com a auto-similaridade da correlação de longo alcance do sinal. Baseado nos valores obtidos de a, é possível distinguir entre os casos de sinais não-correlacionados, tipo ruído branco (a = 0,5), sinal anti-persistentes (a < 0,5) e sinal persistente (a > 0,5). Usando esta metodologia, foram analisadas 129 curvas de luz de sistemas binários de raios-X, provenientes do banco de dados públicos de observações feitas pelo instrumento All Sky Monitor, a bordo do satélite Rossi X-Ray Timing Explorer (ASM-RXTE). Foram identificadas a presença de a'0,5 em mais de 90% dos sistemas estudados, implicando em dizer que as flutuações de intensidade observadas apresentam correlação de auto-similaridade, sem entretanto, indícios de apresentarem uma escala de tempo característica das flutuações de intensidade. Sistemas onde são observadas erupções (flares), apresentam sistematicamente a > 0,5, característica esta, possivelmente associada com persistência das flutuações de densidade de disco ou taxa de acréscimo de massa. Os sistemas com curvas de luz onde nao são observadas as erupções apresentam uma distribuição normal centrada em a~0,62+/-0,10. Referências ¾ Peng, C.-K., Buldyrev, S.V., Havlin, S., Simons, M., Stanley, H.E., e Goldberg, A.L., Phys. Rev. E, (49), 1685 (1994). ¾ Liu, Y., Gopikrishnan, P., Cizeau, P., Meyer, M., Peng,C.-K., e Stanley, H.E., Phys. Rev. E, (60), 1390 (1999).

  13. Key parameters of W UMa-type contact binaries discovered by HIPPARCOS

    NASA Astrophysics Data System (ADS)

    Selam, S. O.

    2004-03-01

    A sample of W UMa-type binaries which were discovered by the HIPPARCOS satellite was constructed with the aid of well defined selection criteria described in this work. The selection process showed up that several systems of which the variability types have been assigned as EB in HIPPARCOS catalogue are genuine contact binaries of W UMa-type. The light curves of the 64 selected systems based on HIPPARCOS photometry were analyzed with the aid of light curve synthesis method by Rucinski and their geometric elements (namely mass ratio q, degree of contact f, and orbital inclination i) were determined. The solutions were obtained for the first time for many of the systems in the sample and would be a good source for their future light curve analyses based on more precise follow-up observations. Based on observations made with the ESA HIPPARCOS astrometry satellite.

  14. X-ray and optical measurements of the cataclysmic variable CH UMa

    NASA Technical Reports Server (NTRS)

    Becker, R. H.; Chanan, G. A.; Wilson, A. S.; Pravdo, S. H.

    1982-01-01

    A program to identify optical counterparts of X-ray sources discovered with the Einstein Observatory has resulted in an independent identification of CH UMa as a cataclysmic variable. Spectrophotometric observations made with the Intensified Image Dissector Scanner on the 2.1-m telescope at KPNO revealed an emission line spectrum from an approximately 15 mag object similar to the spectra of cataclysmic variables. A subsequent search of the Harvard photographic plate collection revealed outbursts of 4 mag in amplitude.

  15. Increasing Supercycle Lengths of Active SU UMa-type Dwarf Novae

    NASA Astrophysics Data System (ADS)

    Otulakowska-Hypka, M.; Olech, A.

    2014-12-01

    We present observational evidence that supercycle lengths of the most active SU UMa-type stars are increasing during the past decades. We analyzed a large number of photometric measurements from available archives and found that this effect is generic for this class of stars, independently of their evolutionary status. This finding is in agreement with previous predictions and the most recent work of Patterson et al. (2012) on BK Lyn.

  16. Thorough analysis and deep insight into the low amplitude W UMa type system FI Boo

    NASA Astrophysics Data System (ADS)

    Papageorgiou, A.; Christopoulou, P.-E.

    2013-02-01

    We present a thorough modeling of new multicolor light curves of the low amplitude W UMa type binary system FI Boo obtained at the University of Patras Observatory "Mythodea", in spring 2012, in view of the presence of a detected third body. The absolute properties of the components were derived with the phoebe software and were tested extensively by heuristic scanning with parameter kicking in order to check the solution uniqueness.

  17. The absolute parameters of two W UMa type binaries in Ursa Majoris

    NASA Astrophysics Data System (ADS)

    Yılmaz, M.; Baştürk, Ö.; Özavcı, İ.; Şenavcı, H. V.; Selam, S. O.

    2015-01-01

    We present the results of simultaneous Wilson-Devinney analyses of light and radial velocity curves of two contact binaries in the constellation Ursa Majoris. We found that HH UMa is an A-subtype W UMa binary, which conflicts with the classification of Han et al. (2014) as a W-subtype. Seasonal variations observed in the light curves of the system are well explained with two cool stellar spots in our solution as opposed to the hot-spot based solution by Han et al. (2014), the presence of which would not cause such rapid period variations. The evolutionary status of the system is in agreement with the findings of our study. We modeled II UMa, another A-subtype overcontact binary, without surface spots and found that its both components have rather low surface gravities indicating an advanced state of evolution pointing to evolved subgiants. The high contact degree (f=74%) supports this viewpoint. Our analysis shows that there is a significant third light contribution, contradicting some of the previous analyses, which lack the detection of the secondary minima as total eclipses because they were not as evident as they are in our light curves.

  18. A cool stellar companion to the δ Scuti variable star GW UMa

    NASA Astrophysics Data System (ADS)

    Wang, S.-M.; Qian, S.-B.; Li, L.-J.; Zhu, L.-Y.; Zhao, E.-G.; Zhou, X.

    2015-01-01

    GW UMa is a new high-amplitude δ Scuti variable star with a period of 0d.20319367. By using a few new determined times of light maximum together with those collected from the literature, the changes in Observed-Calculated (O-C) diagram were analyzed. It is discovered that the O-C curve of GW UMa shows a cyclic variation with a period of 13.2 years and a semi-amplitude of 0.0023 days. The periodic variation was analyzed for the light-travel time effect that may be due to the presence of a stellar companion. The mass of the stellar companion is determined to be M2 sin i=0.11(±0.01)M⊙ when a mass of 1.76 M⊙ for GW UMa is adopted. The two component stars in the binary system are orbiting each other at an orbital separation about 6.5(±0.8) AU. For orbital inclinations i⩾22.6°, the mass of the companion star would be M2<0.3M⊙ and it is a fully convective star. The detection suggests that hidden stellar companions to bright stars may be not unusual.

  19. UBVRI analysis of the totally eclipsing extreme mass ratio W UMa binary, GSC 3208 1986

    SciTech Connect

    Samec, R. G.; Kring, J. D.; Robb, Russell; Van Hamme, W.; Faulkner, D. R.

    2015-03-01

    GSC 3208 1986 is an NSVS and TYCHO binary, first observed from 1999 to 2000. It is a W UMa binary with a period of 0.405 days. The present observations were taken in 2012 September and are of high precision, averaging a standard deviation of better than 5 mmag. The amplitude of the light curve is very nearly 0.5 mag yet it undergoes total eclipses. Dominion Astrophysical Observatory spectra give an F3V type (T∼6900 K) for the system, the earliest of the extreme mass ratio W UMa binaries. The linear period determination of 0.4045672 days was calculated with the two sets of epochs available. An early NSVS light curve reveals that the period has been smoothly decreasing over its past 12,000 orbits. The binary may be undergoing sinusoidal oscillations due to the presence of a third body, possibly with a period of 23±3 years. The high inclination of 85° results in a long duration secondary total eclipse, lasting some 49.5 minutes. Findings indicate that GSC 3208 1986 is an immaculate extreme mass ratio, q(m{sub 2}/m{sub 1}) = 0.24, A-type W UMa binary.

  20. Many factors complicate EM susceptibility tests

    NASA Astrophysics Data System (ADS)

    Richards, R. J.

    1982-09-01

    Procedures and apparatus currently employed for assaying the EM susceptibility of communication, navigation, and EW equipment are described. Susceptibility is examined in either conducted susceptibility tests, where signals are introduced into the input port of the device under test, or in radiated modes, where the entire device is exposed to an EM field to test for component and system failure. Noting that military standards require up to 10 times the EM resistance as commercial standards, the use of shielded enclosures in both commercial and military testing facilities is explored. RF-tight enclosures are filled with a homogeneous EM field produced by, optimally, broadband generators which emit signals which are amplified to desired levels. Sweep functions permit testing under broadband conditions. Attention is given to radiator selection and antenna choice to produce satisfactory test conditions at all frequencies.

  1. Unified Data Resource for CryoEM

    PubMed Central

    Lawson, Catherine L.

    2010-01-01

    3D cryo-electron microscopy reconstruction methods are uniquely able to reveal structures of many important macromolecules and macromolecular complexes. EMDataBank.org, a joint effort of the Protein Data Bank in Europe (PDBe), the Research Collaboratory for Structural Bioinformatics (RCSB), and the National Center for Macromolecular Imaging (NCMI), is a “one-stop shop” resource for global deposition and retrieval of cryoEM map, model and associated metadata. The resource unifies public access to the two major EM Structural Data archives: EM Data Bank (EMDB) and Protein Data Bank (PDB), and facilitates use of EM structural data of macromolecules and macromolecular complexes by the wider scientific community. PMID:20888470

  2. EMS in Taiwan: past, present, and future.

    PubMed

    Chiang, Wen-Chu; Ko, Patrick Chow-In; Wang, Hui-Chih; Yang, Chi-Wei; Shih, Fuh-Yuan; Hsiung, Kuang-Hua; Ma, Matthew Huei-Ming

    2009-01-01

    Taiwan is a small island country located in East Asia. From around 1995 modern concepts of the EMS were imported and supported by legislation. Considerable progress has since been made towards the construction of an effective pre-hospital care system. This article introduces the current status of the EMS in Taiwan, including the systems, response configurations, funding, personnel, medical directorship, and outcome research. The features and problems of in-hospital emergency care are also discussed. Key areas for further development in the country vary depending on regional differences in available resource and population density. An analysis of the strength, weakness, opportunity, and threats of the evolving EMS in Taiwan could be an example for other countries where the EMS is undergoing a similar process of development and optimisation. PMID:19059690

  3. A estabilidade dos PAHS em função da energia da radiação interestelar nas faixas UV e raios-X

    NASA Astrophysics Data System (ADS)

    Pinotti, R.; Costa, R. K.; Boechat-Roberty, H. M.; Lago, A.; Souza, G. B.

    2003-08-01

    A nebulosa CRL 618, uma proto-nebulosa planetária cuja nuvem molecular espessa envolve uma estrela B0, contém uma grande quantidade de C2H2 e CH4. Estas moléculas são consideradas os tijolos da criação de grandes moléculas carbonadas como os Hidrocarbonetos Policíclicos Aromáticos (PAHs). Esta nebulosa, por estar exposta a intensos campos de UV e Raios-X, é uma região de fotodissociação molecular que propicia a formação de novas moléculas, confirmada pela presença de C4H2 e C6H6 (Benzeno), que é a unidade básica dos PAHs. Atribui-se a esta família de moléculas orgânicas duas propriedades fundamentais, a resistência para sobreviver ao campo de radiação UV interestelar e a geração das bandas de emissão não identificadas (UIR) observadas no infravermelho. No entanto, alguns autores questionam a resistência dos PAHs ao campo de radiação UV interestelar. Empregando a técnica de Espectrometria de Massas por Tempo de Vôo, no modo de coincidência fotoelétron-fotoíon, estudamos a ionização e fragmentação das seguintes moléculas: Benzeno, Benzeno deuterado, Naftaleno, Antraceno e Fenantreno. Utilizamos uma fonte de Hélio monocromática em 21,21 eV (584,5 Å) e a radiação Síncroton do Laboratório Nacional de Luz Síncroton (LNLS) em diferentes energias nas proximidades da borda do C 1s ( 290 eV). Comprovamos a estabilidade dos PAHs sob ação de UV (21,21 eV), onde eles apresentam um baixo nível de fotodissociação, produzindo fragmentos ionizados com rendimento total na ordem de 5 por cento em relação ao íon molecular pai. Entretanto, em altas energias, na faixa de Raios-X, a quebra destas moléculas torna-se mais intensa, com a produção de muitos fragmentos. Como uma das rotas de fragmentação do Naftaleno é [(C10H8) = > (C6H6+) + (C4H2) + (e-)], e como temos as evidências observacionais da existência do C4H2 e C6H6 na nebulosa CRL 618, sugerimos que este ambiente também possui o Naftaleno.

  4. A distribuição de velocidades na linha de visada em galáxias barradas vistas de face

    NASA Astrophysics Data System (ADS)

    Gadotti, D. A.; de Souza, R. E.

    2003-08-01

    Com o objetivo de realizar um estudo cinemático da componente vertical de barras em galáxias, obtivemos espectros de fenda longa de alta razão S/N ao longo dos eixos maior e menor de 14 galáxias barradas vistas de face, nos telescópios de 1.52m do ESO em La Silla, Chile, e de 2.3m do Steward Observatory em Kitt Peak, Arizona. Estes dados nos permitiram determinar a distribuição de velocidades das estrelas ao longo do eixo vertical das barras e discos destes sistemas, tanto no centro como em pontos que distam cerca de 5 e 20 segundos de arco do núcleo, correspondendo a distâncias de cerca de 0.7 e 2.8 kpc, respectivamente. Desta forma, a variação radial da distribuição de velocidades também pôde ser avaliada. Este tipo de análise tem raros exemplos na literatura por ser caro em termos de tempo de telescópio. Entretanto, é de fácil justificativa, considerando que traz novas informações que podem ser utilizadas para aperfeiçoar modelos teóricos acerca da formação e evolução de galáxias. Um algoritmo por nós desenvolvido foi utilizado para obter as distribuições de velocidades como Gaussianas generalizadas (polinômios de Gauss-Hermite), o que traz um ingrediente a mais neste tipo de estudo que, tradicionalmente, se utiliza de Gaussianas puras, uma hipótese nem sempre razoável. Apresentaremos os resultados deste trabalho, que incluem um diagnóstico para a identificação de barras recém formadas, e testes para o modelo isotérmico de discos. Mostraremos que: (i) a escolha das estrelas padrão em velocidade, e dos parâmetros da Gaussiana, deve ser muito bem justificada já que tem influência significativa nos resultados; (ii) muitas galáxias apresentam uma depressão na dispersão de velocidades na região central, que pode estar associada a um disco interno; e (iii) a dispersão de velocidades é constante ao longo da barra, nos eixos maior e menor, mas cai substancialmente quando se passa da barra para o disco.

  5. Variação temporal do gradiente radial de o/h a partir de uma amostra de nebulosas planetárias

    NASA Astrophysics Data System (ADS)

    Maciel, W. J.; Costa, R. D. D.; Uchida, M. M. M.

    2003-08-01

    Gradientes radiais de abundância são observados no disco de nossa Galáxia e também em outras galáxias espirais. No caso da Galáxia, o principal problema relativo aos gradientes é sua variação temporal, que constitui um dos principais vínculos aos modelos de evolução química da Galáxia. As nebulosas planetárias são particularmente interessantes no estudo dos gradientes e suas variações, tanto espaciais como temporais. São objetos brilhantes, podendo ser observadas a grandes distâncias, e têm abundâncias relativamente precisas de diversos elementos químicos. Além disso, sendo originadas de estrelas com massas entre 0.8 e 8 massas solares na sequência principal, incluem objetos com idades e populações diferentes, o que as torna especialmente interessantes ao estudo da variação temporal dos gradientes. Neste trabalho, apresentamos resultados recentes sobre a variação temporal do gradiente de O/H a partir de uma amostra contendo cerca de 200 nebulosas, para as quais obtivemos distâncias por métodos estatísticos. As abundâncias foram parcialmente obtidas a partir de observações em Itajubá e La Silla, sendo as restantes obtidas da literatura. Os resultados mostram, pela primeira vez, evidências de um achatamento do gradiente de O/H, de -0.11 dex/kpc para -0.06 dex/kpc nos últimos 9 giga-anos ou de -0.08 dex/kpc para -0.06 dex/kpc nos últimos 5 giga-anos. Esses valores apresentam um bom acordo com alguns modelos recentes para a evolução química da Galáxia. (FAPESP/CNPq)

  6. Infrared photometry of the RS CVn short-period systems - XY UMa and WY Cnc

    SciTech Connect

    Arevalo, M.J.; Lazaro, C. )

    1990-03-01

    Infrared J and K light curves of two RS CVn short-period systems, XY UMa and WY Cnc, are presented. Both systems show similar variability in the infrared to that observed in the visual. From the colors an infrared excess is inferred for the primary component of both systems. A new determination of their geometrical elements is presented and the resulting parameters are compared to those previously obtained from visible photometry. The light curves show peculiarities that may indicate the presence of gas streams in the systems. 27 refs.

  7. The photometric solution of W UMa-type star BW Draconis

    NASA Astrophysics Data System (ADS)

    Zhou, Hong-Nan; Leung, Kam-Ching

    1988-10-01

    The photometric solutions of W UMa-type binary BW Dra have been determined by applying the Wilson and Devinney Code to UBV observations of Rucinski and Kaluzny. It is shown that BW Dra is corresponding to a system with an overcontact configuration. A smaller mass ratio q = 0.392 and UBV light curves give converging solutions with non-zero third light. It is proved that the components of BW Dra are older stars (the spectral types are G0 and G3, respectively). According to the photometric solution and spectroscopic results of Batten and Lu, the absolute parameters are presented, too.

  8. Thorough analysis and deep insight into the low amplitude W UMa type system FI Boo

    NASA Astrophysics Data System (ADS)

    Papageorgiou, A.

    2013-09-01

    We present results of the modeling of new multicolor light curves of the low amplitude W UMa type binary system FI Boo obtained at the University of Patras Observatory "Mythodea", in spring 2012, in view of the presence of a detected third body that may play an important role in the formation and evolution. The absolute properties of the components have been derived from spectroscopic data with the PHOBE software and are tested extensively by heuristic scanning and parameter kicking in order to check the solution uniqueness. The classification as A or W subtype, the formation and the evolutionary status of the binary are also investigated in detail.

  9. A eficiência de formação estelar em Musca

    NASA Astrophysics Data System (ADS)

    Hickel, G. R.; Vilas-Boas, J. W. S.; Roberto, A. J.., Jr.; Khan, R. P.

    2003-08-01

    Apresentamos os resultados de um survey no infravermelho próximo (bandas J e H), executado no Laboratório Nacional de Astrofísica, na direção da nuvem escura em forma de filamento de Musca (observamos ao longo de todo o filamento, além de todas as fontes pontuais IRAS e/ou fontes ROSAT brilhantes a uma distância de 2o da nuvem). Nosso objetivo é determinar a eficiência de formação estelar para esta nuvem escura (massa de estrelas formadas/massa da nuvem), procurando por objetos estelares jovens de pequena massa no seu interior e/ou evoluídos o suficiente para estarem afastados do local de nascimento, mas ainda mostrando características de objetos pré-seqüência principal como emissão de raios-X e excesso de emissão no infravermelho próximo. Este survey não estabeleceu nenhum viés na seleção de fontes pontuais IRAS ou fontes ROSAT, uma vez que a imensa maioria das fontes pontuais IRAS nesta região têm qualidade de fluxo ruim. Os candidatos a objetos estelares jovens foram selecionados pelo excesso no índice de cor (J-H), descontados os efeitos da extinção interestelar na linha de visada, determinada através da emissão estendida no infravermelho distante (IRAS). Estimativas de massa foram feitas para estes candidatos, através da relação massa-luminosidade, para calcular a eficiência de formação estelar de Musca.

  10. EMS adaptation for climate change

    NASA Astrophysics Data System (ADS)

    Pan, C.; Chang, Y.; Wen, J.; Tsai, M.

    2010-12-01

    The purpose of this study was to find an appropriate scenario of pre-hospital transportation of an emergency medical service (EMS) system for burdensome casualties resulting from extreme climate events. A case of natural catastrophic events in Taiwan, 88 wind-caused disasters, was reviewed and analyzed. A sequential-conveyance method was designed to shorten the casualty transportation time and to promote the efficiency of ambulance services. A proposed mobile emergency medical center was first constructed in a safe area, but nearby the disaster area. The Center consists of professional medical personnel who process the triage of incoming patients and take care of casualties with minor injuries. Ambulances in the Center were ready to sequentially convey the casualties with severer conditions to an assigned hospital that is distant from the disaster area for further treatment. The study suggests that if we could construct a spacious and well-equipped mobile emergency medical center, only a small portion of casualties would need to be transferred to distant hospitals. This would reduce the over-crowding problem in hospital ERs. First-line ambulances only reciprocated between the mobile emergency medical center and the disaster area, saving time and shortening the working distances. Second-line ambulances were highly regulated between the mobile emergency medical center and requested hospitals. The ambulance service of the sequential-conveyance method was found to be more efficient than the conventional method and was concluded to be more profitable and reasonable on paper in adapting to climate change. Therefore, additional practical work should be launched to collect more precise quantitative data.

  11. 21 CFR 520.1453 - Moxidectin and praziquantel gel.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...; Gyalocephalus capitatus; and Petrovinema poculatus; small strongyles: undifferentiated lumenal larvae; encysted cyathostomes (late L3 and L4 mucosal cyathostome larvae); ascarids: Parascaris equorum (adults and L4...

  12. 21 CFR 524.775 - Emodepside and praziquantel.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., immature adults, and fourth stage larvae), roundworm infections caused by Toxocara cati (adults and fourth stage larvae), and tapeworm infections caused by Dipylidium caninum (adults) and Taenia...

  13. 21 CFR 524.775 - Emodepside and praziquantel.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., immature adults, and fourth stage larvae), roundworm infections caused by Toxocara cati (adults and fourth stage larvae), and tapeworm infections caused by Dipylidium caninum (adults) and Taenia...

  14. 21 CFR 524.775 - Emodepside and praziquantel.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., immature adults, and fourth stage larvae), roundworm infections caused by Toxocara cati (adults and fourth stage larvae), and tapeworm infections caused by Dipylidium caninum (adults) and Taenia...

  15. 21 CFR 524.775 - Emodepside and praziquantel.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., immature adults, and fourth stage larvae), roundworm infections caused by Toxocara cati (adults and fourth stage larvae), and tapeworm infections caused by Dipylidium caninum (adults) and Taenia...

  16. 21 CFR 520.1453 - Moxidectin and praziquantel gel.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...; Gyalocephalus capitatus; and Petrovinema poculatus; small strongyles: undifferentiated lumenal larvae; encysted cyathostomes (late L3 and L4 mucosal cyathostome larvae); ascarids: Parascaris equorum (adults and L4...

  17. 21 CFR 520.1198 - Ivermectin and praziquantel paste.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral and gastric stages)—Gasterophilus spp...; Hairworms (adults)—Trichostrongylus axei; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots...

  18. 21 CFR 520.1198 - Ivermectin and praziquantel paste.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral and gastric stages)—Gasterophilus spp...; Hairworms (adults)—Trichostrongylus axei; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots...

  19. 21 CFR 520.1198 - Ivermectin and praziquantel paste.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral and gastric stages)—Gasterophilus spp...; Hairworms (adults)—Trichostrongylus axei; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots...

  20. 21 CFR 520.1198 - Ivermectin and praziquantel paste.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral and gastric stages)—Gasterophilus spp...; Hairworms (adults)—Trichostrongylus axei; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots...

  1. 21 CFR 520.1198 - Ivermectin and praziquantel paste.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots (oral and gastric stages)—Gasterophilus spp...; Hairworms (adults)—Trichostrongylus axei; Large-mouth Stomach Worms (adults)—Habronema muscae; Bots...

  2. 21 CFR 520.1453 - Moxidectin and praziquantel gel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...; Gyalocephalus capitatus; and Petrovinema poculatus; small strongyles: undifferentiated lumenal larvae; encysted cyathostomes (late L3 and L4 mucosal cyathostome larvae); ascarids: Parascaris equorum (adults and L4 larval...); large-mouth stomach worms: Habronema muscae (adults); horse stomach bots: Gasterophilus...

  3. 21 CFR 520.1871 - Praziquantel and pyrantel.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... reinfection occurs, treatment may be repeated. (ii) Indications for use. For removal of tapeworms (Dipylidium... stenocephala), and tapeworms (Dipylidium caninum and Taenia pisiformis) in dogs and puppies....

  4. 21 CFR 520.903d - Febantel-praziquantel paste.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...), whipworms (Trichuris vulpis), ascarids (Toxocara canis and Toxascaris leonina), and tapeworms (Dipylidium...), ascarids (Toxocara cati) and tapeworms (Dipylidium caninum and Taenia taeniaeformis). (3) Limitations....

  5. 21 CFR 520.1871 - Praziquantel and pyrantel.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... reinfection occurs, treatment may be repeated. (ii) Indications for use. For removal of tapeworms (Dipylidium... stenocephala), and tapeworms (Dipylidium caninum and Taenia pisiformis) in dogs and puppies....

  6. 21 CFR 520.903d - Febantel-praziquantel paste.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...), whipworms (Trichuris vulpis), ascarids (Toxocara canis and Toxascaris leonina), and tapeworms (Dipylidium...), ascarids (Toxocara cati) and tapeworms (Dipylidium caninum and Taenia taeniaeformis). (3) Limitations....

  7. 21 CFR 520.903d - Febantel-praziquantel paste.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...), whipworms (Trichuris vulpis), ascarids (Toxocara canis and Toxascaris leonina), and tapeworms (Dipylidium...), ascarids (Toxocara cati) and tapeworms (Dipylidium caninum and Taenia taeniaeformis). (3) Limitations....

  8. 21 CFR 520.1871 - Praziquantel and pyrantel.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... reinfection occurs, treatment may be repeated. (ii) Indications for use. For removal of tapeworms (Dipylidium... stenocephala), and tapeworms (Dipylidium caninum and Taenia pisiformis) in dogs and puppies....

  9. 21 CFR 520.1871 - Praziquantel and pyrantel.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... reinfection occurs, treatment may be repeated. (ii) Indications for use. For removal of tapeworms (Dipylidium... stenocephala), and tapeworms (Dipylidium caninum and Taenia pisiformis) in dogs and puppies....

  10. 21 CFR 520.1871 - Praziquantel and pyrantel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... for use. For removal of tapeworms (Dipylidium caninum and Taenia taeniaeformis), hookworms... (Ancylostoma caninum, Ancylostoma braziliense, and Uncinaria stenocephala), and tapeworms (Dipylidium...

  11. 21 CFR 520.903d - Febantel-praziquantel paste.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...), whipworms (Trichuris vulpis), ascarids (Toxocara canis and Toxascaris leonina), and tapeworms (Dipylidium...), ascarids (Toxocara cati) and tapeworms (Dipylidium caninum and Taenia taeniaeformis). (3) Limitations....

  12. 21 CFR 520.1453 - Moxidectin and praziquantel gel.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... and ponies—(1) Amount. Administer by mouth as a single dose: 0.4 mg moxidectin per kilogram and 2.5 mg...); large-mouth stomach worms: Habronema muscae (adults); horse stomach bots: Gasterophilus...

  13. 10 CFR Appendixes E-M to Part 52 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false E Appendixes E-M to Part 52 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Appendixes E-M to Part 52...

  14. 10 CFR Appendixes E-M to Part 52 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false E Appendixes E-M to Part 52 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Appendixes E-M to Part 52...

  15. 10 CFR Appendixes E-M to Part 52 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false E Appendixes E-M to Part 52 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Appendixes E-M to Part 52...

  16. 10 CFR Appendixes E-M to Part 52 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false E Appendixes E-M to Part 52 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Appendixes E-M to Part 52...

  17. 10 CFR Appendixes E-M to Part 52 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false E Appendixes E-M to Part 52 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Appendixes E-M to Part 52...

  18. Processing of Cryo-EM Movie Data.

    PubMed

    Ripstein, Z A; Rubinstein, J L

    2016-01-01

    Direct detector device (DDD) cameras dramatically enhance the capabilities of electron cryomicroscopy (cryo-EM) due to their improved detective quantum efficiency (DQE) relative to other detectors. DDDs use semiconductor technology that allows micrographs to be recorded as movies rather than integrated individual exposures. Movies from DDDs improve cryo-EM in another, more surprising, way. DDD movies revealed beam-induced specimen movement as a major source of image degradation and provide a way to partially correct the problem by aligning frames or regions of frames to account for this specimen movement. In this chapter, we use a self-consistent mathematical notation to explain, compare, and contrast several of the most popular existing algorithms for computationally correcting specimen movement in DDD movies. We conclude by discussing future developments in algorithms for processing DDD movies that would extend the capabilities of cryo-EM even further. PMID:27572725

  19. The highest rate orbital period increasing contact binary LP UMa revisited

    NASA Astrophysics Data System (ADS)

    Guo, D.-F.; Li, K.; Hu, S.-M.; Jiang, Y.-G.; Gao, D.-Y.; Chen, X.

    2016-04-01

    Complete BV(RI)c photometry for the contact binary LP UMa was derived on 2015 February 23 using the 1.0 m telescope at Weihai Observatory of Shandong University. By compiling 66 newly determined times of light minimum with those published in the literature, we investigated the orbital period variation of this binary star. A possible cyclic variation, with a period of 14.84 years and an amplitude of 0.0031 days, was discovered to be superimposed on a long-term period increase (9.32 s century-1). The highest rate of orbital period increase was confirmed, which can be explained by the mass transfer from the less massive component to the more massive one. The cyclic period oscillation was possibly caused by the light travel time effect due to the presence of a third body. The multiple light curves were simultaneously analysed using the W-D program. It was found that LP UMa has a mass ratio of q = 0.331 , a contact degree of f = 7.9 % , and the temperature difference between the two components was only about 90 K, which are quite different with the previous results. A hot spot on the primary component was employed to explain the asymmetric light curve of this binary.

  20. LONG-TERM PHOTOMETRIC ANALYSIS OF THE ACTIVE W UMa-TYPE SYSTEM TU BOOTIS

    SciTech Connect

    Coughlin, Jeffrey L.; Dale, Horace A. III; Williamon, Richard M.

    2008-09-15

    We present multicolor light curves for the W UMa-type eclipsing binary TU Boo for two epochs separated by 22 years. An analysis of the O - C diagram indicates the earlier observations took place right in the middle of a major period change, thus allowing for a unique study on mass transfer and period changes in this W UMa-type system. We compute model fits to our light curves, along with the only other published set, using the Wilson-Devinney program, and find temporally correlated changes in the size of the secondary component with anomalies in the O - C diagram. We investigate the cause of these changes and find support for the existence of rapid, large-scale mass transfer between the components. We postulate that this interaction allows them to maintain nearly equal surface temperatures despite having achieved only marginal contact. We also find support for the evolutionary scenario in which TU Boo has undergone a mass ratio reversal in the past, due to large-scale mass transfer so that what is presently the secondary component of TU Boo is in an advanced evolutionary state, oversized due to a helium-enriched core, with a total system age of {>=}10 Gyr.

  1. Chromospheric activity on late-type star DM UMa using high-resolution spectroscopic observations

    NASA Astrophysics Data System (ADS)

    Zhang, LiYun; Pi, QingFeng; Han, Xianming L.; Chang, Liang; Wang, Daimei

    2016-06-01

    We present new 14 high-resolution echelle spectra to discuss the level of chromospheric activity of DM UMa in {He I} D3, {Na I} D1, D2, Hα, and {Ca II} infrared triplet lines (IRT). It is the first time to discover the emissions above the continuum in the {He I} D3 lines on 2015 February 9 and 10. The emission on February 9 is the strongest one ever detected for DM UMa. We analysed these chromospheric active indicators by employing the spectral subtraction technique. The subtracted spectra reveal weak emissions in the {Na I} D1, D2 lines, strong emission in the Hα line, and clear excess emissions in the {Ca II} IRT lines. Our values for the EW8542/EW8498 ratio are on the low side, in the range of 1.0-1.7. There are also clear phase variations of the level of chromospheric activity in equivalent width (EW) light curves in these chromospheric active lines (especially the Hα line). These phenomena might be explained by flare events or rotational modulations of the level of chromospheric activity.

  2. Risk Communication Within the EM Program

    SciTech Connect

    Edelson, M.

    2003-02-26

    The U.S. Department of Energy Environmental Management program (EM) conducts the most extensive environmental remediation effort in the world. The annual EM budgets have exceeded $6,000,000,000 for approximately ten years and EM has assumed responsibility for the cleanup of the largest DOE reservations (i.e., at Hanford, Washington, Aiken, South Carolina, and Idaho Falls, Idaho) as well as the facilities at Rocky Flats, Colorado and in Ohio. Each of these sites has areas of extensive radioactive and chemical contamination, numerous surplus facilities that require decontamination and removal, while some have special nuclear material that requires secure storage. The EM program has been criticized for being ineffective (1) and has been repeatedly reorganized to address perceived shortcomings. The most recent reorganization was announced in 2001 to become effective at the beginning of the 2003 Federal Fiscal Year (i.e., October 2002). It was preceded by a ''top to bottom'' review (TTBR) of the program (2) that identified several deficiencies that were to be corrected as a result of the reorganization. One prominent outcome of the TTBR was the identification of ''risk reduction'' as an organizing principle to prioritize the activities of the new EM program. The new program also sought to accelerate progress by identifying a set of critical activities at each site that could be accelerated and result in more rapid site closure, with attendant risk, cost, and schedule benefits. This paper investigates how the new emphasis on risk reduction in the EM program has been communicated to EM stakeholders and regulators. It focuses on the Rocky Flats Environmental Technology Site (RFETS) as a case study and finds that there is little evidence for a new emphasis on risk reduction in EM communications with RFETS stakeholders. Discussions between DOE and RFETS stakeholders often refer to ''risk,'' but the word serves as a placeholder for other concepts. Thus ''risk'' communication

  3. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. IV. The Fourth Year (2011-2012)

    NASA Astrophysics Data System (ADS)

    Kato, Taichi; Hambsch, Franz-Josef; Maehara, Hiroyuki; Masi, Gianluca; Miller, Ian; Noguchi, Ryo; Akasaka, Chihiro; Aoki, Tomoya; Kobayashi, Hiroshi; Matsumoto, Katsura; Nakagawa, Shinichi; Nakazato, Takuma; Nomoto, Takashi; Ogura, Kazuyuki; Ono, Rikako; Taniuchi, Keisuke; Stein, William; Henden, Arne; de Miguel, Enrique Kiyota, Seiichiro; Dubovsky, Pavol A.; Kudzej, Igor; Imamura, Kazuyoshi; Akazawa, Hidehiko; Takagi, Ryosuke; Wakabayashi, Yuya; Ogi, Minako; Tanabe, Kenji; Ulowetz, Joseph; Morelle, Etienne; Pickard, Roger D.; Ohshima, Tomohito; Kasai, Kiyoshi; Pavlenko, Elena P.; Antonyuk, Oksana I.; Baklanov, Aleksei V.; Antonyuk, Kirill; Samsonov, Denis; Pit, Nikolaj; Sosnovskij, Aleksei; Littlefield, Colin; Sabo, Richard; Ruiz, Javier; Krajci, Thomas; Dvorak, Shawn; Oksanen, Arto; Hirosawa, Kenji; Goff, William N.; Monard, Berto; Shears, Jeremy; Boyd, David; Voloshina, Irina B.; Shugarov, Sergey Yu.; Chochol, Drahomir; Miyashita, Atsushi; Pietz, Jochen; Katysheva, Natalia; Itoh, Hiroshi; Bolt, Greg; Andreev, Maksim V.; Parakhin, Nikolai; Malanushenko, Viktor; Martinelli, Fabio; Denisenko, Denis; Stockdale, Chris; Starr, Peter; Simonsen, Mike; Tristram, Paul J.; Fukui, Akihiko; Tordai, Tamas; Fidrich, Robert; Paxson, Kevin B.; Itagaki, Koh-ichi; Nakashima, Youichirou; Yoshida, Seiichi; Nishimura, Hideo; Kryachko, Timur V.; Samokhvalov, Andrey V.; Korotkiy, Stanislav A.; Satovski, Boris L.; Stubbings, Rod; Poyner, Gary; Muyllaert, Eddy; Gerke, Vladimir; MacDonald, Walter, II; Linnolt, Michael; Maeda, Yutaka; Hautecler, Hubert

    2013-02-01

    Continuing the project described by Kato et al. (2009, PASJ, 61, S395), we collected times of superhump maxima for 86 SU UMa-type dwarf novae, mainly observed during the 2011-2012 season. We confirmed general trends recorded in our previous studies, such as the relation between period derivatives and orbital periods. There are some systems showing positive period derivatives despite the long orbital period. We observed the 2011 outburst of the WZ Sge-type dwarf nova BW Scl, and recorded an O - C diagram similar to those of previously known WZ Sge-type dwarf novae. The WZ Sge-type dwarf nova OT J184228.1+483742 showed an unusual pattern of double outbursts composed of an outburst with early superhumps and one with ordinary superhumps. We propose an interpretation that a very small growth rate of the 3:1 resonance due to an extremely low mass-ratio led to quenching the superoutburst before the ordinary superhump appeared. We systematically studied ER UMa-type dwarf novae, and found that V1159 Ori showed positive superhumps similar to ER UMa in the 1990s. The recently recognized ER UMa-type object BK Lyn dominantly showed negative superhumps, and its behavior was very similar to the present-day state of ER UMa. The pattern of period variations in AM CVn-type objects was very similar to that of short-period hydrogen-rich SU UMa-type dwarf novae, making them a helium analogue of hydrogen-rich SU UMa-type dwarf novae. SBS 1108+574, a peculiar hydrogen-rich dwarf nova below the period minimum, showed a very similar pattern of period variations to those of short-period SU UMa-type dwarf novae. The mass-ratio derived from the detected orbital period suggests that this secondary is a somewhat evolved star whose hydrogen envelope was mostly stripped during the mass-exchange. CC Scl, MASTER OT J072948.66+593824.4, and OT J173516.9+154708 showed only low-amplitude superhumps with complex profiles. These superhumps are likely to be a combination of two closely separated periods.

  4. Evolução temporal da explosão solar de 06 de junho de 2000 apresentando estruturas finas em rádio freqüências

    NASA Astrophysics Data System (ADS)

    Fernandes, F. C. R.; Sawant, H. S.; Cecatto, J. R.; Caracini, A. G.; Vats, H. O.; Karlický, M.; Meszarosova, H.

    2003-08-01

    Em 06 de junho de 2000 (~15: 00-17: 00 UT), o Brazilian Solar Spectroscope (BSS) registrou uma explosão solar intensa no intervalo de freqüência de (1000-2000) MHz, com alta resolução temporal (100 ms) e espectral (5 MHz). A atividade solar relacionada a esta explosão associada à região ativa (AR) 9026 e classificada como X2.3 foi grande. O Ondrejov Observatory registrou rádio emissões até 4,5 GHz. O satélite SOHO registrou uma série de erupções solares, incluindo uma Ejeção de Massa Coronal (CME) tipo "full-halo" (~15: 54 UT). Explosões tipo II/IV também foram registradas. Na faixa de ondas decimétricas, este evento apresentou dois picos distintos (~15: 21 UT e ~16: 42 UT). O primeiro pico coincide com a explosão registrada em raios-X moles (GOES) e em raios-X duros (Yohkoh). Os espectros dinâmicos com alta resolução do BSS revelaram várias estruturas finas, principalmente emissões tipo "zebra" e "fibra", rádio pulsações, emissões tipo III e do único caso de emissões "zebra" harmônicas observado na faixa decimétrica. Neste trabalho, analisamos a evolução temporal e o comportamento global do evento de 06 de junho de 2000, com ênfase na identificação e associação da ocorrência de cada tipo de estrutura fina registrada em rádio com cada etapa da explosão. Resultados preliminares mostraram que, na fase pré-flare, as estruturas finas apresentaram taxa de deriva negativa (~ 70-190 MHz/s). As emissões tipo "zebra" concentram-se na fase de descida do primeiro pico impulsivo e na de subida do segundo pico. Enquanto que as emissões tipo "fibra" ocorrem em ambas fases, mas preferivelmente durante a fase de descida. Os resultados serão apresentados e discutidos.

  5. On ambiente de binárias de pequena massa em formação: o caso do glóbulo cometário CG30 e IRAS08076-3556

    NASA Astrophysics Data System (ADS)

    Hickel, G. R.; Vilas-Boas, J. W. S.

    2003-08-01

    Neste trabalho, combinamos observações de polarização linear no óptico (banda R), dados no infravermelho distante (IRAS) e observações de transições moleculares em radiofreqüências (CO e espécies isotópicas, HCN e HCO+) para analisar o glóbulo cometário (GC) CG30 (na região da IRAS Vela Shell), que apresenta objetos Herbig-Haro e ejeções de matéria, além de uma fonte pontual IRAS em seu interior. Os objetivos deste estudo são: determinar a eficiência de formação estelar nos glóbulos cometários, através da relação entre a massa total do GC e da massa das estrelas em formação; determinar como o campo magnético influencia na formação de estrelas no interior destes objetos; e analisar as modificações que ejeções de matéria de estrelas em formação causam no gás e no campo magnético dos GCs. Combinando nossos dados com trabalhos já publicados, mostramos que CG30 tem uma eficiência de formação estelar em torno de 3%; que o campo magnético é importante na manutenção da estrutura global do GC e demonstra sinais de torção e compressão; e que a ejeção bipolar de matéria das estrelas do par formam uma ejeção quadripolar, a qual influencia na densidade e temperatura do gás e no grau de polarização dos grãos de poeira associados ao gás do GC.

  6. Do earthquakes generate EM signals?

    NASA Astrophysics Data System (ADS)

    Walter, Christina; Onacha, Stephen; Malin, Peter; Shalev, Eylon; Lucas, Alan

    2010-05-01

    study areas, large swarms of earthquakes were located very close to the electromagnetic coils. This abstract focuses on the data from the Wairakei area. Preliminary data analysis has been carried out by band pass filtering and removing of the harmonics of the 50 Hz power line frequency. The initial results clearly show that electromagnetic signals accompany the seismic P and S waves (coseismic signal). Further data analysis involves the extraction of the seismoelectric signal generated at the onset of the earthquake and at interfaces from the coseismic signal and other ‘noise' sources. This processing step exhibits a major challenge in seismoelectric data processing. Unlike in other studies we measured the EM field and the seismic field at one location. Therefore the seismoelectric wave travelling at the speed of light cannot be determined as easily in the arrival times as when an array of coils is used. This makes the determination of the origin time much more difficult. Hence other processing techniques need to be explored.

  7. VizieR Online Data Catalog: Search for UMa group companions (Ammler-von Eiff+, 2016)

    NASA Astrophysics Data System (ADS)

    Ammler-von Eiff, M.; Bedalov, A.; Kranhold, C.; Mugrauer, M.; Schmidt, T. O. B.; Neuhaeuser, R.; Errmann, R.

    2016-03-01

    The astrometric and photometric data of companion candidates of members of the Ursa Major (UMa) group are presented. They were identified by coronagraphic observations obtained with the S27 camera of NACO at the ESO VLT, Chile, in 2003-2006. Most of the candidates were observed a second time to assess whether they share the proper motion of the star. For this purpose, the change in position with respect to the star was compared to the stellar parallactic and proper motion known from Hipparcos. This way, all candidates with two epochs of observations were rejected being distant background objects. The layout of the included table deviates from the article version to facilitate automatic reading, i.e. the epoch date and the primary name are added to each row, and the candidate identifier is added to the corresponding data set for each epoch. (2 data files).

  8. SU UMa dwarf novae in the period gap showing the negative superhumps

    NASA Astrophysics Data System (ADS)

    Pavlenko, Elena

    2016-07-01

    There are only two known up to date SU UMa dwarf novae in the period gap showing the negative superhumps, namely, MN Dra and 1RXS J003828.7+250920. We present the results of X-ray and spectral investigation for 1RXS J003828.7+250920, multicolor optical investigation for 1RXS J003828.7+250920 and MN Dra at different stages of their activity in 2011-2016 years. We discuss a finding of the accretion disc radius for both dwarf novae, its variation during separated intervals between outbursts for MN Dra as well as high and low temperature regions in quiescent accretion disk for 1RXS J003828.7+250920.

  9. Three X-ray flares near primary eclipse of the RS CVn binary XY UMa

    NASA Astrophysics Data System (ADS)

    Gong, Hang; Osten, Rachel; Maccarone, Thomas; Reale, Fabio; Liu, Ji-Feng; Heckert, Paul A.

    2016-08-01

    We report on an archival X-ray observation of the eclipsing RS CVn binary XY UMa (P orb ≈ 0.48 d). In two Chandra ACIS observations spanning 200 ks and almost five orbital periods, three flares occurred. We find no evidence for eclipses in the X-ray flux. The flares took place around times of primary eclipse, with one flare occurring shortly (< 0.125 P orb) after a primary eclipse, and the other two happening shortly (< 0.05 P orb) before a primary eclipse. Two flares occurred within roughly one orbital period (Δα ≈ 1.024 P orb) of each other. We analyze the light curve and spectra of the system, and investigate coronal length scales during both quiescence and flares, as well as the timing of the flares. We explore the possibility that the flares are orbit-induced by introducing a small orbital eccentricity, which is quite challenging for this close binary.

  10. Ultra-weak magnetic fields in Am stars: β UMa and θ Leo

    NASA Astrophysics Data System (ADS)

    Blazère, A.; Petit, P.; Lignières, F.; Aurière, M.; Böhm, T.; Wade, G.

    2014-12-01

    An extremely weak circularly-polarized signature was recently discovered in spectral lines of the chemically peculiar Am star Sirius A (Petit et al. 2011). This signal was interpreted as a Zeeman signature related to a sub-gauss longitudinal magnetic field, constituting the first detection of a surface magnetic field in an Am star. We present here ultra-deep spectropolarimetric observations of two other bright Am stars, β UMa and θ Leo, observed with the NARVAL spectropolarimeter. The line profiles of the two stars display circularly-polarized signatures similar in shape to the observations gathered for Sirius A. These new detections suggest that very weak magnetic fields may be present in the photospheres of a significant fraction of intermediate-mass stars, although the strongly asymmetric Zeeman signatures measured so far in Am stars (featuring a prominent positive lobe and no detected negative lobe) are not expected in the standard theory of the Zeeman effect.

  11. Mapping of surface activity on the W UMa-type system VW Cephei

    NASA Technical Reports Server (NTRS)

    Bradstreet, David H.; Guinan, Edward F.

    1988-01-01

    After multifilter photometry of the W UMa-type contact binary VW Cep (P = 6.67 hr; G5V + K0V) in 1986/87 revealed large asymmetries in the light curves believed to be caused by large, cool starspot regions on the surface of the larger stars, in Apr. 1987 it was observed with IUE to study the chromospheres and transition regions of the components. During one complete orbital cycle, three SWP and four LWP low dispersion spectra were obtained, including and then excluding the suspected active region. Phase dependent TR line emission strengths were found, most notably C IV, which is 50 percent stronger when the spot region is most visible. The results could be important because VW Cep represents an extreme case for studying stellar dynamo theory and observations can play a crucial role in the unterstanding of magnetic fields and activity cycles in rapidly rotating solar-like stars.

  12. Orbital Period Investigations of Two W UMa-type Binaries: AH Aur and V728 Her

    NASA Astrophysics Data System (ADS)

    Yu, Yun-Xia; Xiang, Fu-Yuan; Hu, Ke

    2016-04-01

    The orbital period changes of two W UMa-type binaries, AH Aur and V728 Her, are investigated based on all available times of the light minimum taken from the databases and literature. It is revealed that the orbital period of AH Aur shows a long-term decrease at a rate of {dP}/{dt}=-2.491× {10}-7 days yr-1. For V728 Her, we find that the orbital period exhibits a secular increase at a rate of {dP}/{dt}=3.793× {10}-7 days yr-1. The secular period changes suggest that AH Aur and V728 Her are undergoing rapid mass transfer between the primary star and the secondary companion.

  13. Sonification of Kepler Field SU UMa Cataclysmic Variable Stars V344 Lyr and V1504 Cyg

    NASA Technical Reports Server (NTRS)

    Tutchton, Roxanne M.; Wood, Matt A.; Still, Martin D.; Howell, Steve B.; Cannizzo, John K.; Smale, Alan P.

    2012-01-01

    Sonification is the conversion of quantitative data into sound. In this work we explain the methods used in the sonification of light curves provided by the Kepler instrument from Q2 through Q6 for the cataclysmic variable systems V344 Lyr and V1504 Cyg . Both systems are SU UMa stars showing dwarf nova outbursts and superoutbursts as well as positive and negative superhumps. Focused sonifications were done from average pulse shapes of each superhump, and separate sonifications of the full, residual light curves were done for both stars. The audio of these data reflected distinct patterns within the evolutions of supercycles and superhumps that matched pervious observations and proved to be effective aids in data analysis.

  14. Precise Orbital Solutions for KEPLER Eclipsing Binaries of W UMa Type Showing Total Eclipses

    NASA Astrophysics Data System (ADS)

    Şenavcı, H. V.; Doǧruel, M. B.; Nelson, R. H.; Yılmaz, M.; Selam, S. O.

    2016-09-01

    We aim to discover the accuracy of photometric mass ratios (q ph) determined for eclipsing binary stars, in the case of the system having at least one `flat bottom' as a minimum profile, as well as the accuracy of data used in that sense. Within this context, we present the results of two-dimensional grid search (q - i) for some W UMa-type eclipsing binaries showing total eclipses, based on the high precision photometric data provided by the KEPLER Mission. The radial velocity data obtained for KIC10618253 in this study, enables us to compare both q ph and the corresponding spectroscopic mass ratio (q sp) values. The results indicate that the high precision photometric data for overcontact eclipsing binaries showing total eclipses allow us to obtain the photometric mass ratios as accurate as the spectroscopic values.

  15. Light Curve Analysis for W UMa-Type Eclipsing Binary Star Systems

    NASA Astrophysics Data System (ADS)

    Henderson, Scott; Peach, N.; Olsen, T.

    2006-12-01

    We report results from summer 2006 in an ongoing study of eclipsing binary stars. Our investigations have focused on the measurement and interpretation of light curves for W UMa-type systems 44i Boötis and VW Cephei. These contact binaries have component stars of spectral type G, and revolve with periods of 6.43 and 6.67 hours. Dome automation and scripting capabilities introduced this summer have significantly reduced experimental uncertainties in our data. In support of previous findings we continue to observe an increase in the orbital period of 44i Boo at a rate of 10.4 µs/epoch or 14.2 ms/yr. Residuals computed after incorporating the increasing period suggest an underlying sinusoidal oscillation with a 61.5 year period and amplitude of 648 seconds. AAPT Member Thomas Olsen is sponsoring the lead presenter, SPS Member Scott Henderson, and the co-presenter, SPS Member Nick Peach.

  16. Photometric and Period Investigation of the Late F-type Overcontact Binary II UMa

    NASA Astrophysics Data System (ADS)

    Zhou, X.; Qian, S.-B.; Zhang, J.; Zhang, B.; Kreiner, J.

    2016-03-01

    II UMa is a late F-type (F5) contact binary with a close-in tertiary and a distant visual companion. According to the four-color (B V RcIc) light curves’ solutions of II UMa, it is a high fill-out (f = 86.6%) and low-mass ratio (q = 0.172) contact binary system, which indicates that it is at the late evolutionary stage of late-type tidal-locked binary stars. The masses of the primary star and secondary star are calculated to be {M}1=1.99{M}⊙ and {M}2=0.34{M}⊙ . The primary star has evolved from the zero-age main sequence, but it still appeared before the terminal-age main sequence, and the secondary star is even more evolved. Considering the mass ratio ({M}3/{M}1=0.67) obtained by spectroscopic observations, the mass of the close-in tertiary is estimated to be {M}3=1.34{M}⊙ . The period variations of the binary system are investigated for the first time. According to the observed-calculated (O-C) curve analysis, a continuous period increase at a rate of {dP}/{dt}=4.88× {10}-7 {day} {{yr}}-1 is determined. The parabolic variation in the O-C curve may be part of a cyclic period of change, or the combined period of change of a parabolic variation and a cyclic one. More instances of minimum light are needed to confirm this. The presence of the tertiary component may play an important role in the formation and evolution of this binary system by drawing angular momentum from the central system during the pre-contact stage.

  17. The E-MS Algorithm: Model Selection with Incomplete Data

    PubMed Central

    Jiang, Jiming; Nguyen, Thuan; Rao, J. Sunil

    2014-01-01

    We propose a procedure associated with the idea of the E-M algorithm for model selection in the presence of missing data. The idea extends the concept of parameters to include both the model and the parameters under the model, and thus allows the model to be part of the E-M iterations. We develop the procedure, known as the E-MS algorithm, under the assumption that the class of candidate models is finite. Some special cases of the procedure are considered, including E-MS with the generalized information criteria (GIC), and E-MS with the adaptive fence (AF; Jiang et al. 2008). We prove numerical convergence of the E-MS algorithm as well as consistency in model selection of the limiting model of the E-MS convergence, for E-MS with GIC and E-MS with AF. We study the impact on model selection of different missing data mechanisms. Furthermore, we carry out extensive simulation studies on the finite-sample performance of the E-MS with comparisons to other procedures. The methodology is also illustrated on a real data analysis involving QTL mapping for an agricultural study on barley grains. PMID:26783375

  18. ANÁLISE DA INSERÇÃO DOS TEMAS DE HUMANIDADES E ÉTICA, COM METODOLOGIA DE APRENDIZAGEM BASEADA EM PROBLEMAS, EM CURRICULO MÉDICO INTEGRADO EM ESCOLA PÚBLICA NO DISTRITO FEDERAL, BRASIL

    PubMed Central

    Novaes, Maria Rita Carvalho Garbi; Novaes, Luiz Carlos Garcez; Guilhem, Dirce; Lolas, Fernando; Silveira, Carla; Guiotti, Murilo

    2009-01-01

    Objetivo Realizar uma análise da inserção da ética e humanidades no currículo do Curso de Medicina da Escola Superior em Ciências da Saúde - ESCS, escola pública do Distrito Federal, Brasil, de forma a contribuir com o processo de gestão curricular. Metodologia O Estudo é de coorte e documental. Foram pesquisados 37 termos relacionados à ética e 36 referentes à humanização nos objetivos educacionais e conteúdo dos módulos temáticos, habilidades e atitudes e interação ensino-serviço-comunidade, de 1a a 4a série e no programa do internato no currículo (ano 2006) e no projeto pedagógico do Curso de Medicina (2001). Resultados Maior inserção da humanização, ética e bioética na 1a e 2a série, quando comparado à inserção na 3a e 4a série e no internato, (IC95%-α=0,034, pvalue=0,007). Unidade de habilidades e atitudes: freqüência das 3 temáticas no currículo da 1a a 4a séries (IC95%-α=0,026, pvalue=0,013). Quando comparada a inserção entre o internato e as quatro primeiras séries, observa-se que nestas a inserção da temática humanização é superior (IC95%-α=0,042, pvalue=0,029). Conclusão O currículo desenvolvido no ano de 2006 na ESCS apresentou correlação com o projeto pedagógico do curso e contemplou a temática de forma abrangente, em todas as séries e internato. PMID:20396594

  19. The LEECH Exoplanet Imaging Survey: Orbit and Component Masses of the Intermediate-age, Late-type Binary NO UMa

    NASA Astrophysics Data System (ADS)

    Schlieder, Joshua E.; Skemer, Andrew J.; Maire, Anne-Lise; Desidera, Silvano; Hinz, Philip; Skrutskie, Michael F.; Leisenring, Jarron; Bailey, Vanessa; Defrère, Denis; Esposito, Simone; Strassmeier, Klaus G.; Weber, Michael; Biller, Beth A.; Bonnefoy, Mickaël; Buenzli, Esther; Close, Laird M.; Crepp, Justin R.; Eisner, Josh A.; Hofmann, Karl-Heinz; Henning, Thomas; Morzinski, Katie M.; Schertl, Dieter; Weigelt, Gerd; Woodward, Charles E.

    2016-02-01

    We present high-resolution Large Binocular Telescope LBTI/LMIRcam images of the spectroscopic and astrometric binary NO UMa obtained as part of the LBT Interferometer Exozodi Exoplanet Common Hunt exoplanet imaging survey. Our H-, Ks-, and L‧-band observations resolve the system at angular separations <0.″09. The components exhibit significant orbital motion over a span of ∼7 months. We combine our imaging data with archival images, published speckle interferometry measurements, and existing spectroscopic velocity data to solve the full orbital solution and estimate component masses. The masses of the K2.0 ± 0.5 primary and K6.5 ± 0.5 secondary are 0.83 ± 0.02 M⊙ and 0.64 ± 0.02 M⊙, respectively. We also derive a system distance of d = 25.87 ± 0.02 pc and revise the Galactic kinematics of NO UMa. Our revised Galactic kinematics confirm NO UMa as a nuclear member of the ∼500 Myr old Ursa Major moving group, and it is thus a mass and age benchmark. We compare the masses of the NO UMa binary components to those predicted by five sets of stellar evolution models at the age of the Ursa Major group. We find excellent agreement between our measured masses and model predictions with little systematic scatter between the models. NO UMa joins the short list of nearby, bright, late-type binaries having known ages and fully characterized orbits. Based on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP and IAC.

  20. Percutaneous absorption and disposition of Tinopal EMS.

    PubMed

    Black, J G; Moule, R C; Philp, J

    1977-08-01

    A cotton-substantive, anionic, fluorescent whitening agent manufactured by several suppliers under various trade names e.g. Tinopal EMS, has been synthesized in radioactive form. Intubation of detergent or aqueous solution into rats resulted in little absorption from the intestinal tract as evidenced by low radioactivity in the urine and tissues. Most of the dose was excreted rapidly in the faeces. After parenteral administration to rats, the radioactivity was rapidly excreted in the faeces with small amounts remaining in tissues and organs. There was slight evidence of retention of radioactivity in the kidneys. Very small amounts of Tinopal EMS in detergent were absorbed through rat skin, but only when concentrations greater than those normally used by the consumer, together with occlusion of the skin were employed. Small amounts were absorbed throught skin when applied in ethanol. It is concluded that the possibility of systemic toxic effects in man as a result of percutaneous absorption is remote. PMID:929616

  1. Crosshole EM in steel-cased boreholes

    SciTech Connect

    Wilt, M.; Lee, K.H.; Becker, A.; Spies, B.; Wang, B.

    1996-07-01

    The application of crosshole EM methods through steel well-casing was investigated in theoretical, laboratory and field studies. A numerical code was developed that calculates the attenuation and phase delay of an EM dipole signal propagated through a steel well casing lodged in a homogeneous medium. The code was validated with a scale model and used for sensitivity studies of casing and formation properties. Finally, field measurements were made in an oil field undergoing waterflooding. Our most important findings are that (1) crosshole surveys are feasible using a well pair with one metallic and one non-metallic casing. (2) The casing effect seems be localized within the pipe section that includes the sensor. (3) The effects of the casing can be corrected using simple means and (4) crosshole field data that are sensitive to both formation and casing were acquired in a working environment.

  2. TandEM: Titan and Enceladus mission

    USGS Publications Warehouse

    Coustenis, A.; Atreya, S.K.; Balint, T.; Brown, R.H.; Dougherty, M.K.; Ferri, F.; Fulchignoni, M.; Gautier, D.; Gowen, R.A.; Griffith, C.A.; Gurvits, L.I.; Jaumann, R.; Langevin, Y.; Leese, M.R.; Lunine, J.I.; McKay, C.P.; Moussas, X.; Muller-Wodarg, I.; Neubauer, F.; Owen, T.C.; Raulin, F.; Sittler, E.C.; Sohl, F.; Sotin, C.; Tobie, G.; Tokano, T.; Turtle, E.P.; Wahlund, J.-E.; Waite, J.H.; Baines, K.H.; Blamont, J.; Coates, A.J.; Dandouras, I.; Krimigis, T.; Lellouch, E.; Lorenz, R.D.; Morse, A.; Porco, C.C.; Hirtzig, M.; Saur, J.; Spilker, T.; Zarnecki, J.C.; Choi, E.; Achilleos, N.; Amils, R.; Annan, P.; Atkinson, D.H.; Benilan, Y.; Bertucci, C.; Bezard, B.; Bjoraker, G.L.; Blanc, M.; Boireau, L.; Bouman, J.; Cabane, M.; Capria, M.T.; Chassefiere, E.; Coll, P.; Combes, M.; Cooper, J.F.; Coradini, A.; Crary, F.; Cravens, T.; Daglis, I.A.; de Angelis, E.; De Bergh, C.; de Pater, I.; Dunford, C.; Durry, G.; Dutuit, O.; Fairbrother, D.; Flasar, F.M.; Fortes, A.D.; Frampton, R.; Fujimoto, M.; Galand, M.; Grasset, O.; Grott, M.; Haltigin, T.; Herique, A.; Hersant, F.; Hussmann, H.; Ip, W.; Johnson, R.; Kallio, E.; Kempf, S.; Knapmeyer, M.; Kofman, W.; Koop, R.; Kostiuk, T.; Krupp, N.; Kuppers, M.; Lammer, H.; Lara, L.-M.; Lavvas, P.; Le, Mouelic S.; Lebonnois, S.; Ledvina, S.; Li, J.; Livengood, T.A.; Lopes, R.M.; Lopez-Moreno, J. -J.; Luz, D.; Mahaffy, P.R.; Mall, U.; Martinez-Frias, J.; Marty, B.; McCord, T.; Salvan, C.M.; Milillo, A.; Mitchell, D.G.; Modolo, R.; Mousis, O.; Nakamura, M.; Neish, C.D.; Nixon, C.A.; Mvondo, D.N.; Orton, G.; Paetzold, M.; Pitman, J.; Pogrebenko, S.; Pollard, W.; Prieto-Ballesteros, O.; Rannou, P.; Reh, K.; Richter, L.; Robb, F.T.; Rodrigo, R.; Rodriguez, S.; Romani, P.; Bermejo, M.R.; Sarris, E.T.; Schenk, P.; Schmitt, B.; Schmitz, N.; Schulze-Makuch, D.; Schwingenschuh, K.; Selig, A.; Sicardy, B.; Soderblom, L.; Spilker, L.J.; Stam, D.; Steele, A.; Stephan, K.; Strobel, D.F.; Szego, K.; Szopa

    2009-01-01

    TandEM was proposed as an L-class (large) mission in response to ESA's Cosmic Vision 2015-2025 Call, and accepted for further studies, with the goal of exploring Titan and Enceladus. The mission concept is to perform in situ investigations of two worlds tied together by location and properties, whose remarkable natures have been partly revealed by the ongoing Cassini-Huygens mission. These bodies still hold mysteries requiring a complete exploration using a variety of vehicles and instruments. TandEM is an ambitious mission because its targets are two of the most exciting and challenging bodies in the Solar System. It is designed to build on but exceed the scientific and technological accomplishments of the Cassini-Huygens mission, exploring Titan and Enceladus in ways that are not currently possible (full close-up and in situ coverage over long periods of time). In the current mission architecture, TandEM proposes to deliver two medium-sized spacecraft to the Saturnian system. One spacecraft would be an orbiter with a large host of instruments which would perform several Enceladus flybys and deliver penetrators to its surface before going into a dedicated orbit around Titan alone, while the other spacecraft would carry the Titan in situ investigation components, i.e. a hot-air balloon (Montgolfi??re) and possibly several landing probes to be delivered through the atmosphere. ?? Springer Science + Business Media B.V. 2008.

  3. Helicopter EMS: Research Endpoints and Potential Benefits

    PubMed Central

    Thomas, Stephen H.; Arthur, Annette O.

    2012-01-01

    Patients, EMS systems, and healthcare regions benefit from Helicopter EMS (HEMS) utilization. This article discusses these benefits in terms of specific endpoints utilized in research projects. The endpoint of interest, be it primary, secondary, or surrogate, is important to understand in the deployment of HEMS resources or in planning further HEMS outcomes research. The most important outcomes are those which show potential benefits to the patients, such as functional survival, pain relief, and earlier ALS care. Case reports are also important “outcomes” publications. The benefits of HEMS in the rural setting is the ability to provide timely access to Level I or Level II trauma centers and in nontrauma, interfacility transport of cardiac, stroke, and even sepsis patients. Many HEMS crews have pharmacologic and procedural capabilities that bring a different level of care to a trauma scene or small referring hospital, especially in the rural setting. Regional healthcare and EMS system's benefit from HEMS by their capability to extend the advanced level of care throughout a region, provide a “backup” for areas with limited ALS coverage, minimize transport times, make available direct transport to specialized centers, and offer flexibility of transport in overloaded hospital systems. PMID:22203905

  4. Test beam performance of CDF plug upgrade EM calorimeter

    SciTech Connect

    Fukui, Y.; CDF Upgrade Group

    1998-01-01

    CDF Plug Upgrade(tile-fiber) EM Calorimeter performed resolution of 15%/{radical}E{circle_plus}0.7% with non-linearity less than 1% in a energy range of 5-180 GeV at Fermilab Test Beam. Transverse uniformity of inside-tower-response of the EM Calorimeter was 2.2% with 56 GeV positron, which was reduced to 1.0% with response map correction. We observed 300 photo electron/GeV in the EM Calorimeter. Ratios of EM Calorimeter response to positron beam to that to {sup 137}Cs Source was stable within 1% in the period of 8 months.

  5. 2. HI PAR (ACQUISITION RADAR) TOWER AND ENLISTED MEN (EM) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. HI PAR (ACQUISITION RADAR) TOWER AND ENLISTED MEN (EM) BARRACKS WITH RADAR ATTACHED. - Nike Hercules Missile Battery Summit Site, Battery Control Administration & Barracks Building, Anchorage, Anchorage, AK

  6. A photometric study of the W UMa-type system U Pegasi

    NASA Astrophysics Data System (ADS)

    Djurašević, G.; Rovithis-Livaniou, H.; Rovithis, P.; Erkapić, S.; Milovanović, N.

    2001-03-01

    In the present study, the activity of the eclipsing binary of the W UMa-type system U Peg is examined by analysing the photoelectric observations covering the period from 1950 to 1989. During this period, the light curves show significant differences and asymmetries. The analysis of the corresponding light curves is made using Djurašević's inverse problem method. To explain the light-curve asymmetries and variations, we used a Roche model that involved regions containing spots on the components. The analysis shows that the system U Peg is in an overcontact configuration (fover ~ 14.9%). The Roche model with spotted areas on the cooler component yields a good fit of the observations for the whole set of the analysed light curves without any changes of the basic system parameters. This indicates that the complex nature of the light-curve variations during the examined period can be explained by the evolution and motion of spotted areas on the cooler component. According to the obtained results, the spotted areas cover a significant part of the stellar surface; the changes in their location and size with time are examined.

  7. Orbital Period Variation and Morphological Light Curve Studies for the W UMa Binary BB Pegasi

    NASA Astrophysics Data System (ADS)

    Hanna, Magdy A.; Awadalla, Nabil S.

    2011-06-01

    The photometric light curves of the W-type W UMa eclipsing contact binary system BB Pegasi have been found to be extremely asymmetric over all the observed 63 years in all wavelengths UBVR. The light curves have been characterized by occultation primary minima. So, the morphology of these light curves has been studied in view of these different asymmetric degrees. The system shows a distinct O'Connell effect as well as depth variation. A 22.96 years cycle, of dark spots group, has been determined for the system combined with about the same cycling for the depth variations (22.78 yr). Also, an analysis of the measurements of mid-eclipse times of BB Peg has been presented. The analysis indicates a period decrease of 5.62× 10-8 d/yr, which can be interpreted in terms of mass transfer of rate -4.38 × 10-8 M_⊙/yr, from the more to the less massive component. The O-C diagram shows a damping sine wave covering two different cycles of 17.0 yr and 12.87 yr with amplitudes equal to 0.0071 and 0.0013 day, respectively. These unequal durations show a non periodicity which may be explained as a result of magnetic activity cycling variations due to star spots. The obtained characteristics are consistent when applying Applegate's (1992) mechanism.

  8. Ultra-weak magnetic fields in Am stars: β UMa and θ Leo

    NASA Astrophysics Data System (ADS)

    Blazère, A.; Petit, P.; Lignières, F.; Aurière, M.; Ballot, J.; Böhm, T.; Folsom, C.; Ariste, A. López; Wade, G. A.

    2015-10-01

    An extremely weak circularly-polarized signature was recently detected in the spectral lines of the Am star Sirius A. With a prominent positive lobe, the shape of the phase-averaged Stokes V line profile is atypical of stellar Zeeman signatures, casting doubts on its magnetic origin. We report here on ultra-deep spectropolarimetric observations of two more bright Am stars: β Uma and θ Leo. Stokes V line signatures are detected in both objects, with a shape and amplitude similar to the one observed on Sirius A. We demonstrate that the amplitude of the Stokes V line profiles depend on various line parameters (Landé factor, wavelength, depth) as expected from a Zeeman signature, confirming that extremely weak magnetic fields are likely present in a large fraction of Am stars. We suggest that the strong asymmetry of the polarized signatures, systematically observed so far in Am stars and never reported in strongly magnetic Ap stars, bears unique information about the structure and dynamics of the thin surface convective shell of Am stars.

  9. THE MULTI-COLOR LIGHT CURVES OF THE W UMa TYPE CONTACT BINARY EP ANDROMEDAE

    SciTech Connect

    Liao, W.-P.; Qian, S.-B.; Li, K.; He, J.-J.; Zhao, E.-G.; Zhou, X.

    2013-10-01

    New multi-color CCD photometric light curves of the eclipsing binary EP And were obtained over six nights in 2006, 2011, and 2012. Using the Wilson-Devinney code, we computed the photometric elements of this system. It was discovered that EP And is a W-type W UMa contact binary system with a mass ratio of q = 2.685 and a degree of contact factor f = 24.9%, rather than an A-type system. Combining 28 newly determined times of minimum light derived from 1999 to 2012 with others collected from the literature, a long-term increase (dP/dt = +5.22 Multiplication-Sign 10{sup -8} days yr{sup -1}) with a sinusoidal variation (A = 0.0109 days; T = 40.89 yr) in the orbital period was found. The orbital period secular increases may be interpreted as conservative mass transfer from the less massive component to the more massive one, and cyclic variations of the orbital period may be caused by the light-travel time effect through the presence of a third body. The evolutionary status and the age of the system are also discussed.

  10. Light curve modeling of the short-period W UMa star GSC 02049-01164

    NASA Astrophysics Data System (ADS)

    Fox-Machado, Lester; Echevarria, Juan; Gonzalez-Buitrago, Diego; Michel, Raul

    2015-08-01

    The preliminary results of an analysis of the time-series photometric data of the binary star GSC 02049-01164 (ROTSE1 J164341.65+251748.1) are presented.GSC 02049-01164 was observed for eight consecutive nights from 2013, May 31 to June 07 UT with the 0.84m telescope of the San Pedro Martir Observatory in Mexico. The data were acquired through a Johnson V filter. The propierties of the GSC 02040-01164 light curve are consistent with a short period contact binary of W UMa type. The light curve is characterized by a small difference between the two out-of-eclipse maxima by about 0.035 mag and a flat bottom at the secondary minimum due to a total eclipse. Moreover, the primary and secondary eclipses accur almost at 0.5 phase interval suggesting a circular orbit. The period of the binary is 0.3256 d. In an effort to gain a better understanding of the binary system and determine its physical properties we have analyzed the light curve with the software PHOEBE V.0 0.31a. We have found that GSC 02049-01164 binary system has a mass ratio of ~ 0.42, an inclination of ~ 85 degrees, a semi-major axis of ~ 2.23 Rsun. The degree of overcontact of the stellar components is about 13 %.

  11. FIRST MODERN PHOTOMETRIC INVESTIGATION OF THE PUZZLING W UMa TYPE CLOSE BINARY SYSTEM OF TZ BOOTIS

    SciTech Connect

    Christopoulou, P.-E.; Parageorgiou, A.; Chrysopoulos, I.

    2011-10-15

    New CCD photometric BVRI observations of the puzzling W UMa type binary star, TZ Bootis, are presented from our observations in 2010. By using the updated version of the Wilson-Devinney code, the first modern photometric solution is deduced from new photometric observations and published spectroscopic data. This low mass ratio binary turns out to be a deep overcontact system with f = 52% of A-subtype. A spot model has been applied to fit the particular features of light curves. Based on our seven new light minimum times and all others compiled from the literature over 70 yr, we studied the orbital period from the O-C curve. It is found that a 31.2 yr cyclic variation exists with an amplitude of 0.033 days, overlaying a secular decrease at a rate of dP/dt = -2.1 x 10{sup -8} days yr{sup -1}. The cyclic period change may indicate that TZ Boo is a triple or a quadruple system as confirmed from the published spectroscopic data. The long-term orbital period decrease is interpreted by mass transfer from the more to the less massive component and/or angular momentum loss by the magnetic breaking which would cause the overcontact degree to increase and finally the binary will evolve into a single rapidly rotating star.

  12. Photometric Study of AH Cancri, a W UMa-Type System in M67

    NASA Astrophysics Data System (ADS)

    Zhang, X. B.; Zhang, R. X.; Deng, L.

    2005-02-01

    We present time-series CCD photometry of AH Cnc, a W UMa-type binary system in the old open cluster M67. Over 3500 measurements in two filters were recorded on 15 nights from 2001 to 2004. From the data, 17 new times of minima for the eclipsing binary were obtained, from which a new ephemeris was derived. The orbital period of the system is refined as 0.36045754 days. A photometric analysis for the obtained light curves is performed based on the Wilson-Devinney code. The photometric solutions reveal a totally eclipsing contact configuration for AH Cnc. The photometric mass ratio is determined to be 0.149+/-0.002. The masses and radii of the components are estimated as 1.21+/-0.08 Msolar and 1.36+/-0.03 Rsolar for the primary and 0.18+/-0.02 Msolar and 0.62+/-0.02 Rsolar for the secondary, respectively. The evolutionary status of the contact system is briefly discussed.

  13. Aquecimento alfvênico viscoso-resistivo em discos de acresção ao redor de estrelas T Tauri clássicas

    NASA Astrophysics Data System (ADS)

    Santana, W. M.; Vasconcelos, M. J.

    2003-08-01

    Com a crescente disponibilidade de dados observacionais sobre estrelas T Tauri, a busca por modelos mais precisos vem se tornando cada vez maior. Estes modelos devem explicar, entre outras coisas, o mecanismo dissipativo responsável pelo transporte de momento angular no disco de acresção que acredita-se, circunda estas estrelas. O mecanismo mais viável, do ponto de vista teórico, é uma instabilidade MHD conhecida como "instabilidade magnetorotacional ou Balbus-Hawley" (IBH). Esta instabilidade veio mostrar que o campo magnético desempenha um papel importante na evolução destes objetos mas requer, no entanto, um acoplamento mínimo entre o gás e o campo magnético no disco que não é atingido para os valores de temperatura obtidos do modelo padrão. Contudo, alguns mecanismos de aquecimento para o disco precisam ser examinados. Neste trabalho, propomos a dissipação de ondas Alfvén como uma fonte de aquecimento para o disco. Se o gás apresentar uma condutividade elétrica finita e viscosidade, teremos um tipo de amortecimento para as ondas denominado amortecimento viscoso-resistivo que será aqui considerado. Este mecanismo é aplicado ao modelo de disco em camadas. Calculam-se as taxas de aquecimento Alfvênico, a temperatura efetiva do disco bem como as taxas de ionização decorrentes deste aquecimento e do aquecimento gerado pela absorção de raios cósmicos. Comparações com os dados observacionais de Kitamura et. al. (2001) são efetuadas, ressaltando-se os pontos comuns entre suas observações e nossos dados teóricos.

  14. Experiências internacionais da aplicação de sistemas de apoio à decisão clínica em gastroenterologia

    PubMed Central

    Tenório, Josceli Maria; Hummel, Anderson Diniz; Sdepanian, Vera Lucia; Pisa, Ivan Torres; de Fátima Marin, Heimar

    2015-01-01

    Objetivo Descrever as experiências recentes com a aplicação de sistemas de apoio à decisão clínica em gastroenterologia, de forma a estabelecer o nível de desenvolvimento, testes e vantagens conferidas à prática médica com a introdução desses softwares. Métodos Foi realizada busca nas bases de dados PubMed, LILACS e ISI Web of Knowledge, utilizando termos relacionados à sistemas de apoio à decisão e à gastroenterogia, incluindo artigos originais publicados no período entre 2005 e 2010. Foram recuperadas 104 publicações, na busca inicial e, após a aplicação dos critérios de inclusão e exclusão, foram eleitos nove estudos para leitura do texto completo. Resultados Os sistemas de apoio à decisão clínica apresentam grande multiplicidade de problemas clínicos e investigação de doenças. Em 89% dos casos, são descritos modelos experimentais para o desenvolvimento de sistemas de apoio à decisão clínica. A descrição dos resultados obtidos por técnicas de inteligência artificial em 78% das publicações. Em dois dos estudos foram realizadas comparações com o médico e em apenas uma publicação um estudo controlado foi descrito, mostrando evidências de melhorias na prática médica. Conclusão Os estudos mostram potenciais benefícios dos sistemas de apoio à decisão clínica à prática médica, porém, estudos controlados em ambiente real devem ser realizados para comprovar esta perspectiva. PMID:26491625

  15. Communication - An Effective Tool for Implementing ISO 14001/EMS

    SciTech Connect

    Rachel Damewood; Bowen Huntsman

    2004-04-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) received ISO 14001/EMS certification in June 2002. Communication played an effective role in implementing ISO 14001/EMS at the INEEL. This paper describes communication strategies used during the implementation and certification processes. The INEEL achieved Integrated Safety Management System (ISMS) and Voluntary Protection Program (VPP) Star status in 2001. ISMS implemented a formal process to plan and execute work. VPP facilitated worker involvement by establishing geographic units at various facilities with employee points of contact and management champions. The INEEL Environmental Management System (EMS) was developed to integrate the environmental functional area into its ISMS and VPP. Since the core functions of ISMS, VPP, and EMS are interchangeable, they were easy to integrate. Communication is essential to successfully implement an EMS. (According to ISO 14001 requirements, communication interacts with 12 other elements of the requirements.) We developed communication strategies that integrated ISMS, VPP, and EMS. For example, the ISMS, VPP, and EMS Web sites communicated messages to the work force, such as “VPP emphasizes the people side of doing business, ISMS emphasizes the system side of doing business, and EMS emphasizes the systems to protect the environment; but they all define work, identify and analyze hazards, and mitigate the hazards.” As a result of this integration, the work force supported and implemented the EMS. In addition, the INEEL established a cross-functional communication team to assist with implementing the EMS. The team included members from the Training and Communication organizations, VPP office, Pollution Prevention, Employee and Media Relations, a union representative, facility environmental support, and EMS staff. This crossfunctional team used various communication strategies to promote our EMS to all organization levels and successfully implemented EMS

  16. Gradiente radial de [Mg/Fe] em duas galáxias elípticas

    NASA Astrophysics Data System (ADS)

    Milone, A.; Capelato, H.

    2003-08-01

    Basicamente, são propostos dois cenários de evolução quí mio-dinâmico para os sistemas esferoidais: (i) o hierárquico através da fusão e/ou acresção de sub-sistemas com ou sem surtos de formação estelar, e (ii) o colapso monolí tico dissipativo com formação estelar interrompida por um vento galáctico. Ambos, dentro de certos limites, conseguem explicar os gradientes internos de metalicidade estelar presentes nas galáxias elí pticas bem como a relação observada entre a metalicidade central e a massa (Mg20 vs. log sv0). No entanto, nenhum prevê uma variação interna para a razão de abundâncias Mg/Fe que indiretamente define a escala temporal da formação estelar. Empregamos a espectroscopia óptica de fenda longa com a finalidade de recuperar as histórias de formação estelar, de enriquecimento quí mico e da dinâmica dentro de determinadas regiões das galáxias. Os espectros de média resolução (FWHM = 7,1 Å) e escala angular de 1,092 arcsec/pixel foram coletados com o telescópio 1,60m do OPD/LNA. Comparamos nossas medidas de linhas de absorção com resultados espectrofotométricos de modelos de populações estelares simples - mais especificamente os í ndices do Sistema Lick como Mg2, Mg b, < Fe > e Hb - a fim de se investigar as variações internas de [Fe/H], [Mg/Fe] e idade. Para duas galáxias elí pticas, NGC 1052 e NGC 7796, pertencentes a ambientes de baixa densidade, encontramos uma variação radial da razão Mg/Fe decrescente do centro para fora em regiões de 0,6 e 1 raio efetivo respectivamente. Discutimos alguns cenários de enriquecimento quí mico para estas duas galáxias.

  17. Determination of parameters of W UMa-type systems - V757 Cen, GW Cep, BX Peg, AH VIR

    NASA Astrophysics Data System (ADS)

    Kaluzny, J.

    Photoelectric light curves of four W UMa-type systems (V757 Cen, GW Cep, BX Peg, AH Vir) have been solved using the Ruciński code. The solutions were obtained for two assumed values of the gravity darkening exponent (β = 0.00 and β = 0.08). It is concluded that it is hard to distinguish between those two values basing on the wide band photometry in the visual wavelength domain.

  18. Survey of period variations of superhumps in SU UMa-type dwarf novae. V. The fifth year (2012-2013)

    NASA Astrophysics Data System (ADS)

    Kato, Taichi; Hambsch, Franz-Josef; Maehara, Hiroyuki; Masi, Gianluca; Nocentini, Francesca; Dubovsky, Pavol A.; Kudzej, Igor; Imamura, Kazuyoshi; Ogi, Minako; Tanabe, Kenji; Akazawa, Hidehiko; Krajci, Thomas; Miller, Ian; de Miguel, Enrique; Henden, Arne; Noguchi, Ryo; Ishibashi, Takehiro; Ono, Rikako; Kawabata, Miho; Kobayashi, Hiroshi; Sakai, Daisuke; Nishino, Hirochika; Furukawa, Hisami; Masumoto, Kazunari; Matsumoto, Katsura; Littlefield, Colin; Ohshima, Tomohito; Nakata, Chikako; Honda, Satoshi; Kinugasa, Kenzo; Hashimoto, Osamu; Stein, William; Pickard, Roger D.; Kiyota, Seiichiro; Pavlenko, Elena P.; Antonyuk, Oksana I.; Baklanov, Aleksei V.; Antonyuk, Kirill; Samsonov, Denis; Pit, Nikolaj; Sosnovskij, Aleksei; Oksanen, Arto; Harlingten, Caisey; Tyyskä, Jenni; Monard, Berto; Shugarov, Sergey Yu.; Chochol, Drahomir; Kasai, Kiyoshi; Maeda, Yutaka; Hirosawa, Kenji; Itoh, Hiroshi; Sabo, Richard; Ulowetz, Joseph; Morelle, Etienne; Michel, Raúl; Suárez, Genaro; James, Nick; Dvorak, Shawn; Voloshina, Irina B.; Richmond, Michael; Staels, Bart; Boyd, David; Andreev, Maksim V.; Parakhin, Nikolai; Katysheva, Natalia; Miyashita, Atsushi; Nakajima, Kazuhiro; Bolt, Greg; Padovan, Stefano; Nelson, Peter; Starkey, Donn R.; Buczynski, Denis; Starr, Peter; Goff, William N.; Denisenko, Denis; Kochanek, Christopher S.; Shappee, Benjamin; Stanek, Krzysztof Z.; Prieto, José L.; Itagaki, Koh-ichi; Kaneko, Shizuo; Stubbings, Rod; Muyllaert, Eddy; Shears, Jeremy; Schmeer, Patrick; Poyner, Gary; Rodríguez-Marco, Miguel

    2014-04-01

    Continuing the project described in Kato et al. (2009, PASJ, 61, S395), we collected times of superhump maxima for SU UMa-type dwarf novae mainly observed during the 2012-2013 season. We found three objects (V444 Peg, CSS J203937, and MASTER J212624) having strongly positive period derivatives despite the long orbital period (Porb). By using the period of growing stage (stage A) superhumps, we obtained mass ratios for six objects. We characterized nine new WZ Sge-type dwarf novae. We made a pilot survey of the decline rate in the slowly fading parts of SU UMa-type and WZ Sge-type outbursts. The decline time scale was found to generally follow an expected P_orb^{1/4} dependence, and WZ Sge-type outbursts also generally follow this trend. There are some objects which show slower decline rates, and we consider these objects good candidates for period bouncers. We also studied unusual behavior in some objects, including BK Lyn which made a transition from an ER UMa-type state to a novalike (standstill) state in 2013, and unusually frequent occurrences of superoutbursts in NY Ser and CR Boo. We applied the least absolute shrinkage and selection operator (Lasso) power spectral analysis, which has been proven to be very effective in analyzing the Kepler data, to the ground-based photometry of BK Lyn, and detected a dramatic disappearance of the signal of negative superhumps in 2013. We suggested that the mass-transfer rates did not strongly vary between the ER UMa-type state and novalike state in BK Lyn, and this transition was less likely caused by a systematic variation of the mass-transfer rate.

  19. EM threat analysis for wireless systems.

    SciTech Connect

    Burkholder, R. J. (Ohio State University Electroscience Laboratory); Mariano, Robert J.; Schniter, P. (Ohio State University Electroscience Laboratory); Gupta, I. J. (Ohio State University Electroscience Laboratory)

    2006-06-01

    Modern digital radio systems are complex and must be carefully designed, especially when expected to operate in harsh propagation environments. The ability to accurately predict the effects of propagation on wireless radio performance could lead to more efficient radio designs as well as the ability to perform vulnerability analyses before and after system deployment. In this report, the authors--experts in electromagnetic (EM) modeling and wireless communication theory--describe the construction of a simulation environment that is capable of quantifying the effects of wireless propagation on the performance of digital communication.

  20. Stochastic EM-based TFBS motif discovery with MITSU

    PubMed Central

    Kilpatrick, Alastair M.; Ward, Bruce; Aitken, Stuart

    2014-01-01

    Motivation: The Expectation–Maximization (EM) algorithm has been successfully applied to the problem of transcription factor binding site (TFBS) motif discovery and underlies the most widely used motif discovery algorithms. In the wider field of probabilistic modelling, the stochastic EM (sEM) algorithm has been used to overcome some of the limitations of the EM algorithm; however, the application of sEM to motif discovery has not been fully explored. Results: We present MITSU (Motif discovery by ITerative Sampling and Updating), a novel algorithm for motif discovery, which combines sEM with an improved approximation to the likelihood function, which is unconstrained with regard to the distribution of motif occurrences within the input dataset. The algorithm is evaluated quantitatively on realistic synthetic data and several collections of characterized prokaryotic TFBS motifs and shown to outperform EM and an alternative sEM-based algorithm, particularly in terms of site-level positive predictive value. Availability and implementation: Java executable available for download at http://www.sourceforge.net/p/mitsu-motif/, supported on Linux/OS X. Contact: a.m.kilpatrick@sms.ed.ac.uk PMID:24931999

  1. CryoEM at IUCrJ: a new era

    PubMed Central

    Subramaniam, Sriram; Kühlbrandt, Werner; Henderson, Richard

    2016-01-01

    In this overview, we briefly outline recent advances in electron cryomicroscopy (cryoEM) and explain why the journal IUCrJ, published by the International Union of Crystallography, could provide a natural home for publications covering many present and future developments in the cryoEM field. PMID:26870375

  2. 7 CFR 1945.20 - Making EM loans available.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Secretary in making a decision on the requested natural disaster determination. (4) The Secretary will... 7 Agriculture 13 2012-01-01 2012-01-01 false Making EM loans available. 1945.20 Section 1945.20...) PROGRAM REGULATIONS (CONTINUED) EMERGENCY Disaster Assistance-General § 1945.20 Making EM loans...

  3. 7 CFR 1945.20 - Making EM loans available.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Secretary in making a decision on the requested natural disaster determination. (4) The Secretary will... 7 Agriculture 13 2011-01-01 2009-01-01 true Making EM loans available. 1945.20 Section 1945.20...) PROGRAM REGULATIONS (CONTINUED) EMERGENCY Disaster Assistance-General § 1945.20 Making EM loans...

  4. Patterns of behavior in Kilauea's Halema`uma`u lava lake during 2011 and 1911

    NASA Astrophysics Data System (ADS)

    Patrick, M. R.; Orr, T. R.

    2011-12-01

    The past three and a half years of activity in the Halema`uma`u vent, at the summit of Kilauea Volcano, have provided a robust observational dataset and allowed us to generalize on many aspects of behavior in the lava lake. The current lava lake normally has been 100-150 m in diameter and contained deep (70-220 m) within a slowly enlarging, fume-filled crater. The lava level fluctuates over both long- and short-term intervals, over a total height range of about 150 m. Over the long term (days to weeks) the lava level correlates directly with summit tilt at a consistent rate, sympathetic with the frequent summit deflation-inflation (DI) events, indicating the lava level is related, in large part, to the pressure state of the summit magma reservoir. On a short term, the lava level experiences rise-fall cycles ("gas pistoning") of 10-20 m height changes, with time spans of minutes to hours, which are due to shallow accumulation and release of gas. The lava lake also abruptly dropped about 150 m during the March 2011 east-rift intrusion and Kamoamoa eruption, presumably due to the rapid evacuation of magma from the summit reservoir. The lava surface is composed of large (decameter-scale) crustal plates, whose size is inversely related to the surface migration velocity. The surface crust moves at a relatively slow velocity (often 0.2-1 m/s), similar to velocities at other lava lakes on Kilauea (Mauna Ulu, Kupaianaha) and elsewhere worldwide (Erebus, Erta Ale), and usually in a direction that is maintained for months. Spattering is generally continuous and directly linked to the circulation pattern; spattering normally occurs at the spot of lava downwelling. Spattering intensity correlates directly with seismic tremor levels, suggesting that the bulk of summit tremor is related to gas release from the lava surface. These characteristics of the modern lava lake have both important similarities and differences compared to the Halema`uma`u lava lake observed by

  5. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae

    NASA Astrophysics Data System (ADS)

    Kato, Taichi; Imada, Akira; Uemura, Makoto; Nogami, Daisaku; Maehara, Hiroyuki; Ishioka, Ryoko; Baba, Hajime; Matsumoto, Katsura; Iwamatsu, Hidetoshi; Kubota, Kaori; Sugiyasu, Kei; Soejima, Yuichi; Moritani, Yuuki; Ohshima, Tomohito; Ohashi, Hiroyuki; Tanaka, Junpei; Sasada, Mahito; Arai, Akira; Nakajima, Kazuhiro; Kiyota, Seiichiro; Tanabe, Kenji; Imamura, Kazuyoshi; Kunitomi, Nanae; Kunihiro, Kenji; Taguchi, Hiroki; Koizumi, Mitsuo; Yamada, Norimi; Nishi, Yuichi; Kida, Mayumi; Tanaka, Sawa; Ueoka, Rie; Yasui, Hideki; Maruoka, Koichi; Henden, Arne; Oksanen, Arto; Moilanen, Marko; Tikkanen, Petri; Aho, Mika; Monard, Berto; Itoh, Hiroshi; Dubovsky, Pavol A.; Kudzej, Igor; Dancikova, Radka; Vanmunster, Tonny; Pietz, Jochen; Bolt, Greg; Boyd, David; Nelson, Peter; Krajci, Thomas; Cook, Lewis M.; Torii, Ken'ichi; Starkey, Donn R.; Shears, Jeremy; Jensen, Lasse-Teist; Masi, Gianluca; Hynek, Tomáš; Nová; K, Rudolf; Kociá; N, Radek; Krá; L, Lukáš; Kučá; Ková, Hana; Kolasa, Marek; Štastný, Petr; Staels, Bart; Miller, Ian; Sano, Yasuo; de Ponthière, Pierre; Miyashita, Atsushi; Crawford, Tim; Brady, Steve; Santallo, Roland; Richards, Tom; Martin, Brian; Buczynski, Denis; Richmond, Michael; Kern, Jim; Davis, Stacey; Crabtree, Dustin; Beaulieu, Kevin; Davis, Tracy; Aggleton, Matt; Morelle, Etienne; Pavlenko, Elena P.; Andreev, Maksim; Baklanov, Alexander; Koppelman, Michael D.; Billings, Gary; Urbancok, L'ubomír; Ögmen, Yenal; Heathcote, Bernard; Gomez, Tomas L.; Voloshina, Irina; Retter, Alon; Mularczyk, Krzysztof; Zoczewski, Kamil; Olech, Arkadiasz; Kedzierski, Piotr; Pickard, Roger D.; Stockdale, Chris; Virtanen, Jani; Morikawa, Koichi; Hambsch, Franz-Josef; Garradd, Gordon; Gualdoni, Carlo; Geary, Keith; Omodaka, Toshihiro; Sakai, Nobuyuki; Michel, Raul; Cárdenas, A. A.; Gazeas, Kosmas D.; Niarchos, Panos G.; Yushchenko, Alexander V.; Mallia, Franco; Fiaschi, Marco; Good, Gerry A.; Walker, Stan; James, Nick; Douzu, Ken-Ichi; Julian, Wm Mack, II; Butterworth, Neil D.; Shugarov, Sergey Yu.; Volkov, Igor; Chochol, Drahomir; Katysheva, Natalia; Rosenbush, Alexander E.; Khramtsova, Maria; Kehusmaa, Petri; Reszelski, Maciej; Bedient, James; Liller, William; Pojmanski, Grzegorz; Simonsen, Mike; Stubbings, Rod; Schmeer, Patrick; Muyllaert, Eddy; Kinnunen, Timo; Poyner, Gary; Ripero, Jose; Kriebel, Wolfgang

    2009-12-01

    We systematically surveyed period variations of superhumps in SU UMa-type dwarf novae based on newly obtained data and past publications. In many systems, the evolution of the superhump period is found to be composed of three distinct stages: an early evolutionary stage with a longer superhump period, a middle stage with systematically varying periods, and a final stage with a shorter, stable superhump period. During the middle stage, many systems with superhump periods of less than 0.08 d show positive period derivatives. We present observational characteristics of these stages and give greatly improved statistics. Contrary to an earlier claim, we found no clear evidence for a variation of period derivatives among different superoutbursts of the same object. We present an interpretation that the lengthening of the superhump period is a result of the outward propagation of an eccentricity wave, which is limited by the radius near the tidal truncation. We interpret that late-stage superhumps are rejuvenated excitation of a 3:1 resonance when superhumps in the outer disk are effectively quenched. The general behavior of the period variation, particularly in systems with short orbital periods, appears to follow a scenario proposed in Kato, Maehara, and Monard (2008, PASJ, 60, L23). We also present an observational summary of WZ Sge-type dwarf novae. Many of them have shown long-enduring superhumps during a post-superoutburst stage having longer periods than those during the main superoutburst. The period derivatives in WZ Sge-type dwarf novae are found to be strongly correlated with the fractional superhump excess, or consequently with the mass ratio. WZ Sge-type dwarf novae with a long-lasting rebrightening or with multiple rebrightenings tend to have smaller period derivatives, and are excellent candidates for those systems around or after the period minimum of evolution of cataclysmic variables.

  6. First Photometric Investigation of the Newly Discovered W UMa-type Binary Star MR Com

    NASA Astrophysics Data System (ADS)

    Qian, S.-B.; Liu, N.-P.; Liao, W.-P.; He, J.-J.; Liu, L.; Zhu, L.-Y.; Wang, J.-J.; Zhao, E.-G.

    2013-08-01

    By analyzing multi-color light curves of the newly discovered W UMa-type binary, MR Com, we discovered that it is a shallow-contact binary with a degree of contact factor of f = 10.0% ± 2.1%. Photometric solutions reveal that MR Com is a W-type system with a mass ratio of q = 3.9 where the less massive component is about 90 K hotter than the more massive one. By investigating all of the available times of minimum light, we found that the general trend of the Observed-Calculated (O - C) curve shows a downward parabolic variation while it undergoes a cyclic variation with a small amplitude of 0.0031 days and a period of 10.1 yr. The downward parabolic change corresponds to a long-term decrease in the orbital period at a rate of \\dot{P}=-5.3\\times {10^{-7}} days yr-1 that may be caused by a combination of a mass transfer and an angular momentum loss (AML) via magnetic braking. Among the 16 shallow-contact systems with a decreasing orbital period, MR Com has the lowest mass ratio (e.g., 1/q = 0.26). The shallow-contact configuration, the low-mass ratio, and the long-term period decrease all suggest that systems similar to MR Com are on the AML-controlled stage of the evolutionary scheme proposed by Qian. They will oscillate around a critical mass ratio and evolve into a deep contact with a higher mass ratio. The small-amplitude cyclic change in the O - C curve was analyzed for the light-travel time effect via the presence of an extremely cool stellar companion.

  7. The First Photometric Investigation of the Neglected W-UMa-type Binary Star UZ CMi

    NASA Astrophysics Data System (ADS)

    Qian, S.-B.; Li, K.; Liao, W.-P.; Liu, L.; Zhu, L.-Y.; He, J.-J.; Wang, J.-J.; Zhao, E.-G.

    2013-04-01

    UZ CMi was a W-UMa-type binary star found more than 80 years ago. However, it has been neglected in photometric investigations. Here, the first complete light curves in the B, V, R, and I bands are presented and analyzed using the Wilson and Devinney method. It is discovered that UZ CMi is a contact binary (f = 38.4(± 2.3)%) with a mass ratio of 0.45. The derived orbital inclination (i = 87°) indicates that it is a total eclipsing binary, which suggests that the determined parameters are reliable. By using 17 new eclipse times together with those collected from the literature, we found that the general trend of the observed-calculated (O - C) curve shows an upward parabolic variation that corresponds to a long-term increase in the orbital period at a rate of \\dot{P}=+4.1× {10^{-8}} days yr-1. The continuous increase may be caused by a mass transfer from the less massive component to the more massive one. This suggests that UZ CMi is in the thermal relaxation oscillation controlled stage of the evolutionary scheme proposed by Qian. UZ CMi will oscillate around a critical mass ratio and the contact configuration cannot be broken. After the upward parabolic change was removed, the (O - C)2 curve of the photoelectric and charge-coupled device data revealed a cyclic variation with a small amplitude of 0.0026 days and a period of 21.1 yr. The cyclic change was analyzed for the light-travel time effect via the presence of an extremely cool stellar companion.

  8. A CCD photometric study of the W UMa contact binary Y Sextantis

    NASA Astrophysics Data System (ADS)

    Yang, Yulan; Liu, Qingyao

    2003-07-01

    A V light curve of the W UMa contact binary Y Sex is presented in this paper. From the observations, two times of minimum light was determined and from the present times of minimum light and those collected from the references, the change in the orbital period of the system was analyzed with the method of Kalimeris et al. [A&A 282 (1994) 775]. The result reveals that the orbital period of the system oscillates with a cycle of about 50 years and an amplitude of 1.1×10 -6 days. The light curve was analyzed by means of the latest version of the Wilson-Devinney code, which was also used to correct photometric effects on the radial-velocity curve obtained by McLean and Hilditch [MNRAS 203 (1983) 1]. The results suggest that Y Sex is an A-subtype contact binary with a mass ratio of q=0.180(2). In the new photometric solution, a positive value of the third light of the system suggests that the sinusoidal variation of the period could be caused by a third component in the system. The absolute dimensions of Y Sex are found to be: M1=1.21(18) M ⊙, M2=0.22(3) M ⊙, R1=1.50(2) R ⊙, R2=0.75(1) R ⊙, L1=3.00(44) L ⊙, L2=0.69(10) L ⊙, A=2.66(11) R ⊙.

  9. An extensive analysis of the triple W UMa type binary FI BOO

    SciTech Connect

    Christopoulou, P.-E.; Papageorgiou, A.

    2013-12-01

    We present a detailed analysis of the interesting W UMa binary FI Boo in view of the spectroscopic signature of a third body through photometry, period variation, and a thorough investigation of solution uniqueness. We obtained new BVR{sub c}I{sub c} photometric data that, when combined with spectroscopic data, enable us to analyze the system FI Boo and determine its basic orbital and physical properties through PHOEBE, as well as the period variation by studying the times of the minima. This combined approach allows us to study the long-term period changes in the system for the first time in order to investigate the presence of a third body and to check extensively the solution uniqueness and the uncertainties of derived parameters. Our modeling indicates that FI Boo is a W-type moderate (f = 50.15% ± 8.10%) overcontact binary with component masses of M {sub h} = 0.40 ± 0.05 M {sub ☉} and M {sub c} = 1.07 ± 0.05 M {sub ☉}, temperatures of T {sub h} = 5746 ± 33 K and T {sub c} = 5420 ± 56 K, and a third body, which may play an important role in the formation and evolution. The results were tested by heuristic scanning and parameter kicking to provide the consistent and reliable set of parameters that was used to obtain the initial masses of the progenitors (1.71 ± 0.10 M {sub ☉} and 0.63 ± 0.01 M {sub ☉}, respectively). We also investigated the evolutionary status of massive components with several sets of widely used isochrones.

  10. KIC 7524178 - an SU UMa-Type Dwarf Nova Predominantly Showing Negative Superhumps throughout Supercycle

    NASA Astrophysics Data System (ADS)

    Kato, Taichi; Osaki, Yoji

    2013-12-01

    We analyzed Kepler long-cadence data of KIC 7524178 (= KIS J192254.92+430905.4), and found that it is an SU UMa-type dwarf nova with frequent normal outbursts. The signal of the negative superhump has always been the dominant one, even during the superoutburst, in contrast to our common knowledge about superhumps in dwarf novae. The signal of the positive superhump was only transiently seen during the superoutburst, and it quickly decayed afterward. The frequency variation of the negative superhump was similar to the two previously studied dwarf novae in the Kepler field, V1504 Cyg and V344 Lyr. This is the first object in which the negative superhumps dominate throughout the supercycle. Nevertheless, the superoutburst was faithfully accompanied by the positive superhump, indicating that the tidal eccentric instability is essential for triggering a superoutburst. All the pieces of evidence strengthen the thermal-tidal instability as being the origin of the superoutburst and supercycle, which makes this object the third example in the Kepler field. This object had an unusually small (˜1.0 mag) outburst amplitude, and we considered that this object has a high mass-transfer rate close to the thermal-stability limit of the accretion disk. The average periods of the negative and positive superhumps, and the candidate period of the orbital motion were 0.07288 d (variable in the range 0.0723-0.0731 d), 0.0785 d (variable in the range 0.0772-0.0788 d), and 0.074606(1) d, respectively.

  11. UBVRI Observations, Analysis and Spectra of the Mature W UMa Contact Binary, V444 And

    NASA Astrophysics Data System (ADS)

    Shebs, Travis; Samec, R. G.; Monroe, S.; Faulkner, D. R.; Robb, R. M.; Van Hamme, W. V.; Chamberlain, H.

    2014-01-01

    We present the first precision UBVRI light curves, synthetic light curve solution, a period study and spectra for the V444 Andromedae, an FO V contact W UMa binary. Observations were taken at Lowell Observatory with the 0.81-m reflector from 28 through 30 September 2012 and the spectra at Dominion Astrophysical Observatory’s (DAO) with the 1.8m telescope on 22 July 2013 at a resolution of 60 Å/mm. We determined three times of minimum light from these observations, JD Hel Min I = 2456199.0239±0.0011, 2456199.9616± 0.0015 and JD Hel Min II = 2456198.7907±0.0005. From our period study we determined an improved linear ephemeris, J.D. Hel Min I = 2456199.9618±0.0003d + 0.46877942±0.00000005×E The period has been stable over the past 9.6 years 7500 orbits). After an extensive mass ratio-search, the lowest residual mass ratio was found to be 0.48. Our final Wilson-Devinney Program computation determined that the system is an A-type W U Ma contact binary with a fill-out of nearly 51%. Despite its temperature (7200-7300 K), two magnetic spots were found on the primary component, a 10 degree radius equatorial dark spot, T-factor=0.88 and a 23 degree radius near polar hot spot, T-factor=1.10. The component temperature difference is only ~80K. These parameters tell us that the V444 And is a mature solar type binary.

  12. Orbital Solutions and Absolute Elements of the W UMa Binary MW Pavonis

    NASA Astrophysics Data System (ADS)

    Alvarez, Gabriella E.; Sowell, James R.; Williamon, Richard M.; Lapasset, Emilio

    2015-08-01

    We present differential UBV photoelectric photometry obtained by Williamon of the short-period A-type W UMa binary MW Pav. With the Wilson-Devinney analysis program, we obtained a simultaneous solution of these observations with the UBV photometry of Lapasset, the V measurements by the ASAS program, and the double-lined radial velocity measurements of Rucinski and Duerbeck. Our solution indicates that MW Pav is in an overcontact state, where both components exceed their critical Roche lobes. We derive masses of M1 = 1.514 ± 0.063 Msolar and M2 = 0.327 ± 0.014 Msolar, and equal-volume radii of R1 = 2.412 ± 0.034 Rsolar and R2 = 1.277 ± 0.019 Rsolar for the primary and secondary, respectively. The system is assumed to have a circular orbit and is seen at an inclination of 86.39° ± 0.63°. The effective temperature of the primary was held fixed at 6900 K, whereas the secondary's temperature was found to be 6969 ± 10 K. The asymmetry of the light curves requires a large, single star spot on the smaller, less massive secondary component. A consistent base solution, with different spot characteristics for the Williamon, Lapasset, and ASAS data, was found. The modeled spot varied little during the 40-year range of photometric observations. The combined solution utilized a third light component and found that the period is changing at a rate of dP/dt = (6.50 ± 0.19) × 10-10.

  13. BVRI Photometric Analysis of the W UMa Binary, V428, in the field of NGC188

    NASA Astrophysics Data System (ADS)

    Samec, Ronald G.; Maloney, David Edward; Clark, Jeremy; Caton, Daniel B.; Faulkner, Danny R.

    2015-01-01

    V428 is a faint 15th magnitude binary observed in a study of the open cluster NGC188. However, its distance from the core of the cluster might exclude its membership. Its light curve was classified as a short period EB type eclipsing binary with a period of 0.3079 d and amplitude of ~0.7 mags in all curves. V428 was observed as a part of our student/professional collaborative studies of interacting binaries from data taken from Dark Sky Observatory of Appalachian State University, North Carolina. The difference in component temperatures is some DT =180 K and its fill-out is 35%. This undoubtedly has a semi-extreme mass ratio (q) otherwise its fill-out might dictate a smaller △T. A brief, 2.5 year period study gives, as expected, a constant period, P=0.3076789 d. Five times of minimum light were calculated, 3 primary and 2 secondary eclipses from our present observations:HJD I = 2456598.6746±0.0007, 2456599.5990±0.0014, 2456600.8292±0.0013HJD II = 2456598.8299±0.0026, 2456599.7548±0.0025.The improved linear ephemeris is:JD Hel MinI = 2456599.5990(±0.0010) + 0.30767885(±0.00000043)d X E (1)More monitoring is needed to determine its true orbital evolution. The inclination, 80º is not quite enough to produce total eclipses, so a q-search was performed. Our best solution gives a q=0.4. A cool spot was modeled on the primary component to take care of the light curve asymmetries. It is a K-type W UMa contact binary.

  14. THE FIRST PHOTOMETRIC INVESTIGATION OF THE NEGLECTED W-UMa-TYPE BINARY STAR UZ CMi

    SciTech Connect

    Qian, S.-B.; Li, K.; Liao, W.-P.; Liu, L.; Zhu, L.-Y.; He, J.-J.; Wang, J.-J.; Zhao, E.-G.

    2013-04-15

    UZ CMi was a W-UMa-type binary star found more than 80 years ago. However, it has been neglected in photometric investigations. Here, the first complete light curves in the B, V, R, and I bands are presented and analyzed using the Wilson and Devinney method. It is discovered that UZ CMi is a contact binary (f = 38.4({+-} 2.3)%) with a mass ratio of 0.45. The derived orbital inclination (i = 87 Degree-Sign ) indicates that it is a total eclipsing binary, which suggests that the determined parameters are reliable. By using 17 new eclipse times together with those collected from the literature, we found that the general trend of the observed-calculated (O - C) curve shows an upward parabolic variation that corresponds to a long-term increase in the orbital period at a rate of P-dot = +4.1 x 10{sup -8} days yr{sup -1}. The continuous increase may be caused by a mass transfer from the less massive component to the more massive one. This suggests that UZ CMi is in the thermal relaxation oscillation controlled stage of the evolutionary scheme proposed by Qian. UZ CMi will oscillate around a critical mass ratio and the contact configuration cannot be broken. After the upward parabolic change was removed, the (O - C){sub 2} curve of the photoelectric and charge-coupled device data revealed a cyclic variation with a small amplitude of 0.0026 days and a period of 21.1 yr. The cyclic change was analyzed for the light-travel time effect via the presence of an extremely cool stellar companion.

  15. FIRST PHOTOMETRIC INVESTIGATION OF THE NEWLY DISCOVERED W UMa-TYPE BINARY STAR MR Com

    SciTech Connect

    Qian, S.-B.; Liu, N.-P.; Liao, W.-P.; He, J.-J.; Liu, L.; Zhu, L.-Y.; Wang, J.-J.; Zhao, E.-G.

    2013-08-01

    By analyzing multi-color light curves of the newly discovered W UMa-type binary, MR Com, we discovered that it is a shallow-contact binary with a degree of contact factor of f = 10.0% {+-} 2.1%. Photometric solutions reveal that MR Com is a W-type system with a mass ratio of q = 3.9 where the less massive component is about 90 K hotter than the more massive one. By investigating all of the available times of minimum light, we found that the general trend of the Observed-Calculated (O - C) curve shows a downward parabolic variation while it undergoes a cyclic variation with a small amplitude of 0.0031 days and a period of 10.1 yr. The downward parabolic change corresponds to a long-term decrease in the orbital period at a rate of P-dot = -5.3 x 10{sup -7} days yr{sup -1} that may be caused by a combination of a mass transfer and an angular momentum loss (AML) via magnetic braking. Among the 16 shallow-contact systems with a decreasing orbital period, MR Com has the lowest mass ratio (e.g., 1/q = 0.26). The shallow-contact configuration, the low-mass ratio, and the long-term period decrease all suggest that systems similar to MR Com are on the AML-controlled stage of the evolutionary scheme proposed by Qian. They will oscillate around a critical mass ratio and evolve into a deep contact with a higher mass ratio. The small-amplitude cyclic change in the O - C curve was analyzed for the light-travel time effect via the presence of an extremely cool stellar companion.

  16. Infrasonic harmonic tremor and degassing bursts from Halema'uma'u Crater, Kilauea Volcano, Hawaii

    NASA Astrophysics Data System (ADS)

    Fee, David; GarcéS, Milton; Patrick, Matt; Chouet, Bernard; Dawson, Phil; Swanson, Don

    2010-11-01

    The formation, evolution, collapse, and subsequent resurrection of a vent within Halema'uma'u Crater, Kilauea Volcano, produced energetic and varied degassing signals recorded by a nearby infrasound array between 2008 and early 2009. After 25 years of quiescence, a vent-clearing explosive burst on 19 March 2008 produced a clear, complex acoustic signal. Near-continuous harmonic infrasonic tremor followed this burst until 4 December 2008, when a period of decreased degassing occurred. The tremor spectra suggest volume oscillation and reverberation of a shallow gas-filled cavity beneath the vent. The dominant tremor peak can be sustained through Helmholtz oscillations of the cavity, while the secondary tremor peak and overtones are interpreted assuming acoustic resonance. The dominant tremor frequency matches the oscillation frequency of the gas emanating from the vent observed by video. Tremor spectra and power are also correlated with cavity geometry and dynamics, with the cavity depth estimated at ˜219 m and volume ˜3 × 106 m3 in November 2008. Over 21 varied degassing bursts were observed with extended burst durations and frequency content consistent with a transient release of gas exciting the cavity into resonance. Correlation of infrasound with seismicity suggests an open system connecting the atmosphere to the seismic excitation process at depth. Numerous degassing bursts produced very long period (0.03-0.1 Hz) infrasound, the first recorded at Kilauea, indicative of long-duration atmospheric accelerations. Kilauea infrasound appears controlled by the exsolution of gas from the magma, and the interaction of this gas with the conduits and cavities confining it.

  17. Photometric Analysis of the Recently Discovered W UMa Star NR Camelopardalis: Period Change and Spot Migration

    NASA Astrophysics Data System (ADS)

    Shoup, Jenae; Reed, Phillip A.; Joner, Michael D.; Jensen, Eric L. N.; Collins, Karen A; Pepper, Joshua

    2014-06-01

    NR Cam is a short period (P=0.26 days) eclipsing binary of the W UMa type that was relatively recently discovered in the ROTSE1 data of the Northern Sky Variability Survey (NSVS) and was originally listed in the New Catalog of Suspected Variable Stars (NSV) with the identifier NSV 3754. Here we present the first known detailed study of NR Cam, which includes multi-band light curves, color curves, and a photometric orbital solution. NR Cam exhibits a strong O'Connell effect that can be attributed to magnetically induced spot activity on one of the components. Absolute photometry was performed in B and V at the Kutztown University Observatory in 2013 October and November and complementary high precision differential light curves were obtained in BVRI at the same time, as part of the KELT follow-up network, at Brigham Young University's West Mountain Observatory, Swarthmore College's Peter Van de Kamp Observatory, and the University of Louisville's Moore Observatory. After the B-V color curves were used to approximate the stellar surface temperatures and spot locations, the Wilson-Devinney code was employed with a differential corrections routine to determine the most likely stellar properties and orbital parameters. Our solution indicates that the two stars are in contact, sharing a common envelope, and their surface temperatures are approximately 4500 K and 4200 K. The inclination of the orbit was determined to be 68.0 (±0.6) degrees. When compared with the NSVS data, we find that the orbital period of NR Cam has changed over the past decade and that the strength of the O'Connell effect, and the associated spot activity, has also varied significantly.

  18. Infrasonic harmonic tremor and degassing bursts from Halema'uma'u Crater, Kilauea Volcano, Hawaii

    USGS Publications Warehouse

    Fee, David; Garcés, Milton; Patrick, Matt; Chouet, Bernard; Dawson, Phil; Swanson, Donald A.

    2010-01-01

    The formation, evolution, collapse, and subsequent resurrection of a vent within Halema'uma'u Crater, Kilauea Volcano, produced energetic and varied degassing signals recorded by a nearby infrasound array between 2008 and early 2009. After 25 years of quiescence, a vent-clearing explosive burst on 19 March 2008 produced a clear, complex acoustic signal. Near-continuous harmonic infrasonic tremor followed this burst until 4 December 2008, when a period of decreased degassing occurred. The tremor spectra suggest volume oscillation and reverberation of a shallow gas-filled cavity beneath the vent. The dominant tremor peak can be sustained through Helmholtz oscillations of the cavity, while the secondary tremor peak and overtones are interpreted assuming acoustic resonance. The dominant tremor frequency matches the oscillation frequency of the gas emanating from the vent observed by video. Tremor spectra and power are also correlated with cavity geometry and dynamics, with the cavity depth estimated at ~219 m and volume ~3 x 106 m3 in November 2008. Over 21 varied degassing bursts were observed with extended burst durations and frequency content consistent with a transient release of gas exciting the cavity into resonance. Correlation of infrasound with seismicity suggests an open system connecting the atmosphere to the seismic excitation process at depth. Numerous degassing bursts produced very long period (0.03-0.1 Hz) infrasound, the first recorded at Kilauea, indicative of long-duration atmospheric accelerations. Kilauea infrasound appears controlled by the exsolution of gas from the magma, and the interaction of this gas with the conduits and cavities confining it.

  19. V344 Lyrae: A Touchtone SU UMa Cataclysmic Variable in the Kepler Field

    NASA Technical Reports Server (NTRS)

    Smale, Alan P.; Wood, Matt A.; Still, Martin D.; Howell, Steve B.; Cannizzo, John K.

    2012-01-01

    We report on the analysis of the Kepler short-cadence (SC) light curve of V344 Lyr obtained during 2009 June 20 through 2010 Mar 19 (Q2-Q4). The system is an SU UMa star showing dwarf nova outbursts and superoutbursts, and promises to be a touchstone for CV studies for the foreseeable future. The system displays both positive and negative super humps with periods of 2.20 and 2.06-hr, respectively, and we identify an orbital period of 2.11-hr. The positive super humps have a maximum amplitude of approximately 0.025-mag, the negative super humps a maximum amplitude of approximately 0.8 mag, and the orbital period at quiescence has an amplitude of approximately 0.025 mag. The quality of the Kepler data is such that we can test vigorously the models for accretion disk dynamics that have been emerging in the past several years. The SC data for V344 Lyr are consistent with the model that two physical sources yield positive superhumps: early in the superoutburst. the superhump signal is generated by viscous dissipation within the periodically flexing disk. but late in the superoutburst, the signal is generated as the accretion stream bright spot sweeps around the rim of the non-axisymmetric disk. The disk super humps are roughly anti-phased with the stream/late superhumps. The V344 Lyr data also reveal negative super humps arising from accretion onto a tilted disk precessing in the retrograde direction, and suggest that negative superhumps may appear during the decline of DN outbursts. The period of negative superhumps has a positive P(raised dot) in between outbursts.

  20. Click-EM for imaging metabolically tagged nonprotein biomolecules.

    PubMed

    Ngo, John T; Adams, Stephen R; Deerinck, Thomas J; Boassa, Daniela; Rodriguez-Rivera, Frances; Palida, Sakina F; Bertozzi, Carolyn R; Ellisman, Mark H; Tsien, Roger Y

    2016-06-01

    EM has long been the main technique for imaging cell structures with nanometer resolution but has lagged behind light microscopy in the crucial ability to make specific molecules stand out. Here we introduce click-EM, a labeling technique for correlative light microscopy and EM imaging of nonprotein biomolecules. In this approach, metabolic labeling substrates containing bioorthogonal functional groups are provided to cells for incorporation into biopolymers by endogenous biosynthetic machinery. The unique chemical functionality of these analogs is exploited for selective attachment of singlet oxygen-generating fluorescent dyes via bioorthogonal 'click chemistry' ligations. Illumination of dye-labeled structures generates singlet oxygen to locally catalyze the polymerization of diaminobenzidine into an osmiophilic reaction product that is readily imaged by EM. We describe the application of click-EM in imaging metabolically tagged DNA, RNA and lipids in cultured cells and neurons and highlight its use in tracking peptidoglycan synthesis in the Gram-positive bacterium Listeria monocytogenes. PMID:27110681

  1. The Orthogonally Partitioned EM Algorithm: Extending the EM Algorithm for Algorithmic Stability and Bias Correction Due to Imperfect Data.

    PubMed

    Regier, Michael D; Moodie, Erica E M

    2016-05-01

    We propose an extension of the EM algorithm that exploits the common assumption of unique parameterization, corrects for biases due to missing data and measurement error, converges for the specified model when standard implementation of the EM algorithm has a low probability of convergence, and reduces a potentially complex algorithm into a sequence of smaller, simpler, self-contained EM algorithms. We use the theory surrounding the EM algorithm to derive the theoretical results of our proposal, showing that an optimal solution over the parameter space is obtained. A simulation study is used to explore the finite sample properties of the proposed extension when there is missing data and measurement error. We observe that partitioning the EM algorithm into simpler steps may provide better bias reduction in the estimation of model parameters. The ability to breakdown a complicated problem in to a series of simpler, more accessible problems will permit a broader implementation of the EM algorithm, permit the use of software packages that now implement and/or automate the EM algorithm, and make the EM algorithm more accessible to a wider and more general audience. PMID:27227718

  2. Modelo de atmosfera solar ajustado às observações do raio solar em 17GHz

    NASA Astrophysics Data System (ADS)

    Selhorst, C. L.; Silva, A. V. R.; Costa, J. E. R.

    2003-08-01

    O estudo das variações do raio solar durante o ciclo de atividades do Sol e das diferenças em relação à sua distribuição angular nos fornece informações importantes sobre as mudanças na estrutura da atmosfera solar. Neste trabalho foram analisados mais de 3600 mapas do Sol em 17 GHz obtidos pelo Rádio Heliógrafo de Nobeyama (NoRH), durante 1 ciclo de atividade solar (1992-2003). O raio solar foi definido no ponto onde a temperatura de brilho do mapa era equivalente à metade da temperatura do Sol calmo (temperatura mais comum no mapa).Em relação à sua variação ao longo do ciclo solar, o estudo foi dividido em duas partes: a) ajuste de uma circunferência a pontos distribuídos ao redor do Sol todo. Este estudo mostrou uma variação correlacionada com o ciclo de atividade do Sol. b) ajuste da circunferência a pontos situados somente nas regiões polares. Neste caso os resultados mostraram que o raio polar sofre pouca variação durante o ciclo, com tendência à anticorrelação com este. Além disto, a média do raio polar, durante o período analisado, foi 1" menor que o raio medido no Sol todo. Para estudar a distribuição angular do raio solar, comparamos a média da distribuição de 10 mapas no período de mínima atividade solar com a média de 10 mapas no período de máximo, este estudo mostrou um grande aumento do raio na região equatorial no período de máxima atividade solar. As medidas do raio foram usadas como um dos parâmetros para a criação de um modelo atmosférico (além da temperatura de brilho do Sol e do abrilhantamento do limbo observado), onde mostramos que um modelo atmosférico com a região de transição situada a 3500 km fornece um raio 5" menor que as medidas observacionais. Esta incompatibilidade do modelo com os dados observacionais foi contornada com a inclusão de espículas, estas fazem com que o raio solar aumente proporcionalmente à altura que estas atingem na atmosfera solar. A anticorrelação do raio

  3. A Proposed Activity for a Meaningful Learning about the Moon Phases. (Breton Title: Uma Proposta de Atividade Para a Aprendizagem Significativa sobre as Fases da Lua.) Una Actividad Propuesta Para EL Aprendizaje Significativo Acerca de Las Fases de la Luna

    NASA Astrophysics Data System (ADS)

    Martins, Bruno Andrade; Langhi, Rodolfo

    2012-12-01

    This paper presents one of the concepts of Astronomy and its consequent failure in teaching this topic in high school, even when the official documents point out the necessity of Astronomy teaching at this school level. Among the spontaneous conceptions in Astronomy that high school students carry with them, even after the end of the school, we emphasized in this research the Moon phases. The development of different strategies in relation to traditional methods, aimed to teaching-learning process on this topic was considered in this study. These strategies were devised based on the reference frame of the Meaningful Learning, as elaborated by Ausubel. The proposals presented here include the active participation of students in experimental activities and other didactic activities, for their continuous evaluation during the process. These activities finished with a Comics elaboration about the Moon phases. Therefore, the objective of this paper is to present a proposal for differentiated teaching activity about Moon phases supported by the theoretical principles of Meaningful Learning at Physics classes. Este texto foca um dos conteúdos de Astronomia e a consequente falha no ensino deste tema no ensino médio, apesar de os documentos oficiais apresentarem a necessidade de se trabalhar a Astronomia neste nível de ensino. Dentre as concepções alternativas em Astronomia que os alunos do ensino médio carregam consigo, mesmo após o término dos estudos, destacamos, nesta pesquisa, o fenômeno das fases da Lua. O desenvolvimento de estratégias diferenciadas em relação ao ensino tradicional, visando o processo de ensino-aprendizagem sobre este tema, foi contemplado neste trabalho como um dos resultados obtidos sob a luz dos referenciais da aprendizagem significativa, fundamentados em Ausubel. Segundo a proposta aqui apresentada, a participação ativa dos alunos na execução de uma atividade experimental e outras atividades didáticas, que visam sua cont

  4. Ventos em supergigantes B[e] das nuvens de Magalhães e da Galáxia

    NASA Astrophysics Data System (ADS)

    de Araújo, F. X.; Pilling, D. A.; Pereira, C. B.; Fernandes, M. B.

    2003-08-01

    As Supergigantes B[e] apresentam as seguintes características: (i) alta luminosidade; (ii) espectro típico de estrelas de tipo B; (iii) linhas permitidas e proibidas em emissão de metais de baixa ionização, especialmente FeII; (iv) linhas de Balmer, e por vêzes também dos ions HeI e FeII, com perfis tipo P Cygni indicativos de altas taxas de perda de massa. Atualmente estamos desenvolvendo um projeto que visa comparar as propriedades fisicas (principalmente e v¥) dos ventos destes objetos nas Nuvens de Magalhães e na Galaxia. O objetivo é estudar a influência da metalicidade. No presente painel apresentamos uma determinação das velocidades terminais de 11 estrelas, sendo 4 na GNM (Hen S111, 66, R126 e Hen S93), 4 na PNM (Hen S18, S23, S65 e R4) e 3 na Galaxia (CPD-529243, MWC 300 e GG Car). Nossos dados são espectros de alta resolução obtidos no telescópio 1.52m do ESO com o espectrógrafo FEROS. Para determinar as velocidades terminais usamos as linhas Hd e HeI 3888 Å cujas componentes em absorção costumam estar livres de "blends" e estruturas. Nossos resultados sugerem que as velocidades de expansão na GNM são maiores (ainda que apenas ligeiramente) do que aquelas da PNM, como esperado. No entanto, os objetos da Galaxia não parecem seguir a mesma tendência.

  5. WZ Cephei: A Dynamically Active W UMa-Type Binary Star

    NASA Astrophysics Data System (ADS)

    Jeong, Jang-Hae; Kim, Chun-Hwey

    2011-09-01

    An intensive analysis of 185 timings of WZ Cep, including our new three timings, was made to understand the dynamical picture of this active W UMa-type binary. It was found that the orbital period of the system has complexly varied in two cyclical components superposed on a secularly downward parabola over about 80y. The downward parabola, corresponding to a secular period decrease of -9.d97 × 10-8 y-1, is most probably produced by the action of both angular momentum loss (AML) due to magnetic braking and mass-transfer from the massive primary component to the secondary. The period decrease rate of -6.d72 × 10-8 y-1 due to AML contributes about 67% to the observed period decrease. The mass flow of about 5.16 × 10-8 M⊙ y-1 from the primary to the secondary results the remaining 33% period decrease. Two cyclical components have an 11.y8 period with amplitude of 0.d0054 and a 41.y3 period with amplitude of 0.d0178. It is very interesting that there seems to be exactly in a commensurable 7:2 relation between their mean motions. As the possible causes, two rival interpretations (i.e., light-time effects (LTE) by additional bodies and the Applegate model) were considered. In the LTE interpretation, the minimum masses of 0.30 M⊙ for the shorter period and 0.49 M⊙ for the longer one were calculated. Their contributions to the total light were at most within 2%, if they were assumed to be main-sequence stars. If the LTE explanation is true for the WZ Cep system, the 7:2 relation found between their mean motions would be interpreted as a stable 7:2 orbit resonance produced by a long-term gravitational interaction between two tertiary bodies. In the Applegate model interpretation, the deduced model parameters indicate that the mechanism could work only in the primary star for both of the two period modulations, but could not in the secondary. However, we couldn't find any meaningful relation between the light variation and the period variability from the historical

  6. Evaluation of Fracture Azimuth by EM Wave and Elastic Wave

    NASA Astrophysics Data System (ADS)

    Feng, X.; Wang, Q.; Liu, C.; Lu, Q.; Zeng, Z.; Liang, W.; Yu, Y.; Ren, Q.

    2013-12-01

    Fracture system plays an important role in the development of underground energy, for example enhanced geothermal system (EGS), oil shale and shale gas, etc. Therefore, it becomes more and more important to detect and evaluate the fracture system. Geophysical prospecting is an useful method to evaluate the characteristics of the subsurface fractures. Currently, micro-seismology, multi-wave seismic exploration, and electromagnetic (EM) survey are reported to be used for the purpose. We are studying a method using both elastic wave and EM wave to detect and evaluate the fracture azimuth in laboratory. First, we build a 3D horizontal transverse isotropy (HTI) model, shown in the figure 1, by dry parallel fractures system, which was constructed by plexiglass plates and papers. Then, we used the ultrasonic system to obtain reflected S-wave data. Depending on the shear wave splitting, we evaluated the fracture azimuth by the algorithm of Pearson correlation coefficient. In addition, we used the full Polarimetric ultra wide band electromagnetic (FP-UWB-EM) wave System, shown in the figure 2, to obtain full polarimetric reflected EM-wave data. Depending on the rotation of the EM wave polarimetry, we evaluated the fracture azimuth by the the ration between maximum amplitude of co-polarimetric EM wave and maximum amplitude of cross-polarimetric EM wave. Finally, we used both EM-wave data and S-wave data to evaluate the fracture azimuth by the method of cross plot and statistical mathematics. To sum up, we found that FP-UWB-EM wave can be used to evaluated the fracture azimuth and is more accurate than ultrasound wave. Also joint evaluation using both data could improve the precision.

  7. Refinement of atomic models in high resolution EM reconstructions using Flex-EM and local assessment

    PubMed Central

    Joseph, Agnel Praveen; Malhotra, Sony; Burnley, Tom; Wood, Chris; Clare, Daniel K.; Winn, Martyn; Topf, Maya

    2016-01-01

    As the resolutions of Three Dimensional Electron Microscopic reconstructions of biological macromolecules are being improved, there is a need for better fitting and refinement methods at high resolutions and robust approaches for model assessment. Flex-EM/MODELLER has been used for flexible fitting of atomic models in intermediate-to-low resolution density maps of different biological systems. Here, we demonstrate the suitability of the method to successfully refine structures at higher resolutions (2.5–4.5 Å) using both simulated and experimental data, including a newly processed map of Apo-GroEL. A hierarchical refinement protocol was adopted where the rigid body definitions are relaxed and atom displacement steps are reduced progressively at successive stages of refinement. For the assessment of local fit, we used the SMOC (segment-based Manders’ overlap coefficient) score, while the model quality was checked using the Qmean score. Comparison of SMOC profiles at different stages of refinement helped in detecting regions that are poorly fitted. We also show how initial model errors can have significant impact on the goodness-of-fit. Finally, we discuss the implementation of Flex-EM in the CCP-EM software suite. PMID:26988127

  8. Refinement of atomic models in high resolution EM reconstructions using Flex-EM and local assessment.

    PubMed

    Joseph, Agnel Praveen; Malhotra, Sony; Burnley, Tom; Wood, Chris; Clare, Daniel K; Winn, Martyn; Topf, Maya

    2016-05-01

    As the resolutions of Three Dimensional Electron Microscopic reconstructions of biological macromolecules are being improved, there is a need for better fitting and refinement methods at high resolutions and robust approaches for model assessment. Flex-EM/MODELLER has been used for flexible fitting of atomic models in intermediate-to-low resolution density maps of different biological systems. Here, we demonstrate the suitability of the method to successfully refine structures at higher resolutions (2.5-4.5Å) using both simulated and experimental data, including a newly processed map of Apo-GroEL. A hierarchical refinement protocol was adopted where the rigid body definitions are relaxed and atom displacement steps are reduced progressively at successive stages of refinement. For the assessment of local fit, we used the SMOC (segment-based Manders' overlap coefficient) score, while the model quality was checked using the Qmean score. Comparison of SMOC profiles at different stages of refinement helped in detecting regions that are poorly fitted. We also show how initial model errors can have significant impact on the goodness-of-fit. Finally, we discuss the implementation of Flex-EM in the CCP-EM software suite. PMID:26988127

  9. Environmental Education and Development Division (EM-522). Annual report, Fiscal year 1993

    SciTech Connect

    Not Available

    1993-12-31

    The Environmental Education and Development Division (EM-522) is one of three divisions within the Office of Technology Integration and Environmental Education and Development (EM-52) in Environmental Restoration and Waste Management`s (EM`s) Office of Technology Development (EM-50). The primary design criterion for EM-522 education activities is directly related to meeting EM`s goal of environmental compliance on an accelerated basis and cleanup of the 1989 inventory of inactive sites and facilities by the year 2019. Therefore, EM-522`s efforts are directed specifically toward stimulating knowledge and capabilities to achieve the goals of EM while contributing to DOE`s overall goal of increasing scientific, mathematical, and technical literacy and competency. This report discusses fiscal year 1993 activities.

  10. Electromagnetic optimization of EMS-MAGLEV systems

    SciTech Connect

    Andriollo, M.; Martinelli, G.; Morini, A.; Tortella, A.

    1998-07-01

    In EMS-MAGLEV high-speed transport systems, devices for propulsion, levitation and contactless on-board electric power transfer are combined in a single electromagnetic structure. The strong coupling among the windings affects the performance of each device and requires the utilization of numerical codes. The paper describes an overall optimization procedure, based on a suitable mathematical model of the system, which takes into account several items of the system performance. The parameters of the model are calculated by an automated sequence of FEM analyses of the configuration. Both the linear generator output characteristics and the propulsion force ripple are improved applying the procedure to a reference configuration. The results are compared with the results obtained by a sequence of partial optimizations operating separately on two different subsets of the geometric parameters.

  11. DOE EM industry programs robotics development

    SciTech Connect

    Staubly, R.; Kothari, V.

    1997-12-01

    The Office of Science and Technology (OST) manages an aggressive program for RD&D, as well as testing and evaluation for the U.S. Department of Energy`s (DOE) Environmental Management (EM) organization. The goal is to develop new and improved environmental restoration and waste management technologies to clean up the inventory of the DOE weapons complex faster, safer, and cheaper than is possible with currently available technologies. OST has organized technology management activities along focus teams for each major problem area. There are currently five focus areas: decontamination and decommissioning, tanks, subsurface contaminants, mixed waste, and plutonium. In addition, OST is pursuing research and development (R&D) that cuts across these focus areas by having applications in two or more focus areas. Currently, there are three cross-cutting programs: the robotics technology development; characterization, monitoring, and sensor technologies; and efficient separations and processing.

  12. Online EM with weight-based forgetting.

    PubMed

    Celaya, Enric; Agostini, Alejandro

    2015-05-01

    In the online version of the EM algorithm introduced by Sato and Ishii ( 2000 ), a time-dependent discount factor is introduced for forgetting the effect of the old estimated values obtained with an earlier, inaccurate estimator. In their approach, forgetting is uniformly applied to the estimators of each mixture component depending exclusively on time, irrespective of the weight attributed to each unit for the observed sample. This causes an excessive forgetting in the less frequently sampled regions. To address this problem, we propose a modification of the algorithm that involves a weight-dependent forgetting, different for each mixture component, in which old observations are forgotten according to the actual weight of the new samples used to replace older values. A comparison of the time-dependent versus the weight-dependent approach shows that the latter improves the accuracy of the approximation and exhibits much greater stability. PMID:25710091

  13. Processing of Structurally Heterogeneous Cryo-EM Data in RELION.

    PubMed

    Scheres, S H W

    2016-01-01

    This chapter describes algorithmic advances in the RELION software, and how these are used in high-resolution cryo-electron microscopy (cryo-EM) structure determination. Since the presence of projections of different three-dimensional structures in the dataset probably represents the biggest challenge in cryo-EM data processing, special emphasis is placed on how to deal with structurally heterogeneous datasets. As such, this chapter aims to be of practical help to those who wish to use RELION in their cryo-EM structure determination efforts. PMID:27572726

  14. Telescópio de pequeno porte como suporte ao ensino em cidades com intensa poluição luminosa II

    NASA Astrophysics Data System (ADS)

    Pereira, P. C. R.; Santos-Júnior, J. M.; Cruz, W. S.

    2003-08-01

    Para a maioria dos estudantes, sua passagem pelo ensino formal fundamental envolve a transmissão de fatos que devem ser guardados para um exame, a habilidade para lembrar fórmulas e, eventualmente, a repetição de experimentos que devem produzir resultados exigidos pelo professor. O resultado deste modelo de ensino, ao longo dos anos, é conhecido por todos: desconhecimento e descontentamento, por parte dos estudantes, de temas relativos ao papel e aos processos da ciência. Acreditamos que a Astronomia, pelo seu caráter observacional, é uma das áreas do conhecimento que pode contribuir neste cenário. A Fundação Planetário da Cidade do Rio de Janeiro possui um telescópio Meade LX-200 (25cm) que, juntamente com as câmeras CCD ST-7E e ST8E, tem sido utilizado em projetos voltados aos estudantes do ensino médio desde o ano 2000. Tais projetos envolvem a condução de um projeto de pesquisa observacional num nível apropriado, e possibilitam o contato com técnicas e novas tecnologias: computador, software para manipulação de dados e gráficos, programas de tratamento e redução de dados, uso de equipamentos óptico-eletrônicos (telescópio e CCD), bem como o processo de aquisição de conhecimento. Dentro da proposta dos anos anteriores, priorizamos projetos de uma noite, ou seja, procuramos trabalhar com fenômenos que apresentem variabilidade com intervalo de recorrência relativamente curto. Em todos os casos, optamos pela fotometria diferencial, que tem se mostrado bastante eficiente para o céu luminoso como o da cidade do Rio de Janeiro. Neste painel, apresentamos alguns dos projetos desenvolvidos no último ano, com 25 estudantes. Apresentamos os resultados da observação da variável pulsante AI Vel (V = 6,6) e da variável cataclísmica FO Aqr (V = 13,5), e do monitoramento do trânsito da lua de Júpiter, Europa, ocorrido em 30 de abril de 2003. As curvas de luz produzidas para as primeiras estão concordantes com as da literatura, assim

  15. Basic Concepts of Astronomy: a Methodological Proposal. (Spanish Title: Conceptos Básicos de Astronomía: Una Propuesta Metodológica.) Conceitos Básicos de Astronomia: Uma Proposta Metodológica

    NASA Astrophysics Data System (ADS)

    Darroz, Luiz Marcelo; Heineck, Renato; Samudio Pérez, Carlos Ariel

    2011-12-01

    obtenidos en diferentes momentos, por los comentarios efectuados por los participantes durante las actividades y por los altos índices de aprobación al final de la etapa, consideramos que la propuesta atingió los objetivos establecidos y puede ser repetida con certeza de éxito. Neste relato, descreve-se o desenvolvimento de uma proposta metodológica que aborda conceitos básicos de astronomia fundamentada pedagogicamente na Aprendizagem Significativa. A proposta, que compreende quatro encontros, foi desenvolvida por professores e acadêmicos do curso de Licenciatura em Física da Universidade de Passo Fundo (UPF), através de um curso de extensão, a um grupo de dez estudantes do ensino médio de uma escola pública da cidade de Passo Fundo, RS. O trabalho centrou-se em conceitos básicos de astronomia. Os indícios da aprendizagem significativa foram obtidos por instrumentos de pesquisa e avaliação aplicados ao término de cada encontro. A avaliação da proposta foi efetuada através de um questionário final respondido pelos participantes ao término do desenvolvimento das atividades. Pelos resultados obtidos nos diferentes instrumentos, pelos comentários efetuados pelos participantes durante as atividades e pelos altos índices de aprovação alcançados no questionário final, consideramos que a proposta atingiu os objetivos estabelecidos e pode ser repetida com convicção de sucesso.

  16. Tendências De Teses e Dissertações Sobre Educação em Astronomia No Brasil

    NASA Astrophysics Data System (ADS)

    Bretones, Paulo Sergio; Megid Neto, Jorge

    2005-07-01

    Apresentam-se os resultados de uma pesquisa do tipo estado da arte sobre teses e dissertações defendidas no Brasil e relativas ao ensino de Astronomia, com objetivo de identificar essa produção e conhecer as principais tendências da pesquisa nesse campo. Foram localizadas 13 dissertações de mestrado e 3 teses de doutorado, as quais foram estudadas em função dos seguintes aspectos: isntituição, ano de defesa, nível escolar abrangido no estudo, foco temático do estudo e gênero de trabalho acadêmico. Pretende-se assim colaborar com a divulgação ampla da produção acadêmica na área. Ao mesmo tempo o estudo possibilita, a partir de investigações decorrentes, apontar as contribuições dessa produção para o ensino e sinalizar com necessidades a serem supridas por futuras pesquisas.

  17. Time sequence spectroscopy of AW UMa. The 518 nm Mg I triplet region analyzed with broadening functions

    SciTech Connect

    Rucinski, Slavek M.

    2015-02-01

    High-resolution spectroscopic observations of AW UMa, obtained on three consecutive nights with a median time resolution of 2.1 minutes, have been analyzed using the broadening function method in the spectral window of 22.75 nm around the 518 nm Mg i triplet region. Doppler images of the system reveal the presence of vigorous mass motions within the binary system; their presence puts into question the solid-body rotation assumption of the contact binary model. AW UMa appears to be a very tight, semi-detached binary; the mass transfer takes place from the more massive to the less massive component. The primary, a fast-rotating star with Vsini=181.4±2.5 km s{sup −1}, is covered with inhomogeneities: very slowly drifting spots and a dense network of ripples more closely participating in its rotation. The spectral lines of the primary show an additional broadening component (called the “pedestal”) that originates either in the equatorial regions, which rotate faster than the rest of the star by about 50 km s{sup −1}, or in an external disk-like structure. The secondary component appears to be smaller than predicted by the contact model. The radial velocity field around the secondary is dominated by accretion of matter transferred from (and possibly partly returned to) the primary component. The parameters of the binary are Asini=2.73±0.11 R{sub ⊙} and M{sub 1}sin{sup 3}i=1.29±0.15 M{sub ⊙}, M{sub 2}sin{sup 3}i=0.128±0.016 M{sub ⊙}. The mass ratio, q{sub sp}=M{sub 2}/M{sub 1}=0.099±0.003, while still the most uncertain among the spectroscopic elements, is substantially different from the previous numerous and mutually consistent photometric investigations which were based on the contact model. It should be studied why photometry and spectroscopy give such discrepant results and whether AW UMa is an unusual object or if only very high-quality spectroscopy can reveal the true nature of W UMa-type binaries.

  18. Test beam performance of CDF plug upgrade EM calorimeter

    SciTech Connect

    Fukui, Y.

    1998-11-01

    CDF Plug Upgrade(tile-fiber) EM Calorimeter performed resolution of 15{percent}/{radical} (E) {circle_plus}0.7{percent} with non-linearity less than 1{percent} in a energy range of 5{endash}180 GeV at Fermilab Test Beam. Transverse uniformity of inside-tower-response of the EM Calorimeter was 2.2{percent} with 56 GeV positron, which was reduced to 1.0{percent} with response map correction. We observed 300 photo electron/GeV in the EM Calorimeter. Ratios of EM Calorimeter response to positron beam to that to {sup 137}C{sub s} Source was stable within 1{percent} in the period of 8 months. {copyright} {ital 1998 American Institute of Physics.}

  19. E.M. and Hadronic Shower Simulation with FLUKA

    SciTech Connect

    Battistoni, G.; Fasso, A.; Ferrari, A.; Ranft, J.; Rubbia, A.; Sala, P.R.; /INFN, Milan /SLAC /CERN /Siegen U. /Zurich, ETH

    2005-10-03

    A description of the main features of e.m. and hadronic shower simulation models used in the FLUKA code is summarized and some recent applications are discussed. The general status of the FLUKA project is also reported.

  20. 7 CFR 759.6 - EM to be made available.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Agriculture under the Plant Protection Act or the animal quarantine laws, as defined in section 2509 of the Food, Agriculture, Conservation, and Trade Act of 1990, automatically authorizes EM for production...

  1. 7 CFR 759.6 - EM to be made available.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Agriculture under the Plant Protection Act or the animal quarantine laws, as defined in section 2509 of the Food, Agriculture, Conservation, and Trade Act of 1990, automatically authorizes EM for production...

  2. NASA EM Followup of LIGO-Virgo Candidate Events

    NASA Technical Reports Server (NTRS)

    Blackburn, Lindy L.

    2011-01-01

    We present a strategy for a follow-up of LIGO-Virgo candidate events using offline survey data from several NASA high-energy photon instruments aboard RXTE, Swift, and Fermi. Time and sky-location information provided by the GW trigger allows for a targeted search for prompt and afterglow EM signals. In doing so, we expect to be sensitive to signals which are too weak to be publicly reported as astrophysical EM events.

  3. EM Telemetry Tool for Deep Well Drilling Applications

    SciTech Connect

    Jeffrey M. Gabelmann

    2005-11-15

    This final report discusses the successful development and testing of a deep operational electromagnetic (EM) telemetry system, produced under a cooperative agreement with the United States Department of Energy's National Energy Technology Laboratory. This new electromagnetic telemetry system provides a wireless communication link between sensors deployed deep within oil and gas wells and data acquisition equipment located on the earth's surface. EM based wireless telemetry is a highly appropriate technology for oil and gas exploration in that it avoids the need for thousands of feet of wired connections. In order to achieve the project performance objectives, significant improvements over existing EM telemetry systems were made. These improvements included the development of new technologies that have improved the reliability of the communications link while extending operational depth. A key element of the new design is the incorporation of a data-fusion methodology which enhances the communication receiver's ability to extract very weak signals from large amounts of ambient environmental noise. This innovative data-fusion receiver based system adapts advanced technologies, not normally associated with low-frequency communications, and makes them work within the harsh drilling environments associated with the energy exploration market. Every element of a traditional EM telemetry system design, from power efficiency to reliability, has been addressed. The data fusion based EM telemetry system developed during this project is anticipated to provide an EM tool capability that will impact both onshore and offshore oil and gas exploration operations, for conventional and underbalanced drilling applications.

  4. A New Look at the Eclipse Timing Variation Diagram Analysis of Selected 3-body W UMa Systems

    NASA Astrophysics Data System (ADS)

    Christopoulou, P.-E.; Papageorgiou, A.

    2015-07-01

    The light travel effect produced by the presence of tertiary components can reveal much about the origin and evolution of over-contact binaries. Monitoring of W UMa systems over the last decade and/or the use of publicly available photometric surveys (NSVS, ASAS, etc.) has uncovered or suggested the presence of many unseen companions, which calls for an in-depth investigation of the parameters derived from cyclic period variations in order to confirm or reject the assumption of hidden companion(s). Progress in the analysis of eclipse timing variations is summarized here both from the empirical and the theoretical points of view, and a more extensive investigation of the proposed orbital parameters of third bodies is proposed. The code we have developed for this, implemented in Python, is set up to handle heuristic scanning with parameter perturbation in parameter space, and to establish realistic uncertainties from the least squares fitting. A computational example is given for TZ Boo, a W UMa system with a spectroscopically detected third component. Future options to be implemented include MCMC and bootstrapping.

  5. Comparing the precision 2009 and 2012 light curves of the precontact W UMa binary V1001 Cassiopeia

    SciTech Connect

    Samec, R. G.; Koenke, S. S.; Faulkner, D. R.

    2015-01-01

    A 2012 follow up to the analysis of 2009 observations is presented for the very short period (∼0.43 days) precontact W UMa binary (PCWB) V1001 Cassiopeia. Its short period, similar to the majority of W UMa binaries, and its distinct EA light curve make it a very rare and interesting system for continuing photometric investigation. Previous photometric VRI standard magnitudes give a K4 spectral type. Our solutions of light curves separated by some three years give approximately the same physical parameters. However, the spots have radically changed in temperature, area, and position. While only one dark spot was used to model the first curves, two hot spots are now needed. This affects the overall shape of the light curve, especially in the secondary eclipses in B and V. Additional eclipse timings now show that the orbital period is changing. We conclude that spots are very active on this solar-type dwarf system and that it may mimic its larger cousins, the RS CVn binaries. The conclusion is that analysis now needs to be directed at the continuous time evolution of PCWBs.

  6. A HF EM installation allowing simultaneous whole body and deep local EM hyperthermia.

    PubMed

    Mazokhin, V N; Kolmakov, D N; Lucheyov, N A; Gelvich, E A; Troshin, I I

    1999-01-01

    The structure and main features of a HF EM installation based upon a new approach for creating electromagnetic fields destined for whole body (WBH) and deep local (DLH) hyperthermia are discussed. The HF EM field, at a frequency of 13.56 MHz, is created by a coplanar capacity type applicator positioned under a distilled water filled bolus that the patient is lying on. The EM energy being released directly in the deep tissues ensures effective whole body heating to required therapeutic temperatures of up to 43.5 degrees C, whereas the skin temperature can be maintained as low as 39-40.5 degrees C. For DLH, the installation is equipped with additional applicators and a generator operating at a frequency of 40.68 MHz. High efficiency of the WBH applicator makes it possible to carry out the WBH procedure without any air-conditioning cabin. Due to this, a free access to the patient's body during the WBH treatment is provided and a simultaneous WBH/DLH or WBH/LH procedure by means of additional applicators is possible. Controllable power output in the range of 100-800 W at a frequency of 13.56 MHz and 50-350 W at a frequency of 40.68 MHz allows accurate temperature control during WBH, DLH and WBH/DLH procedures. SAR patterns created by the WBH and DLH applicators in a liquid muscle phantom and measured by means of a non-perturbing E-dipole are investigated. The scattered EM field strength measured in the vicinity of the operating installation during the WBH, DLH and WBH/DLH procedures does not exceed security standards. Examples of temperature versus time graphs in the course of WBH, DLH and WBH/DLH procedures in clinics are presented. The installation is successfully used in leading oncological institutions of Russia and Belarus, though combined WBH/DLH procedures are evidently more complicated and demand thorough planning and temperature measurements to avoid overheating. PMID:10458570

  7. Analysis of EM dataset with several sensor configurations obtained by the loop-loop EM survey on magnetic anomalies

    NASA Astrophysics Data System (ADS)

    CHOI, J.; Yi, M. J.; Sasaki, Y.; Son, J.; Nam, M. J.

    2015-12-01

    Most of mineral mines in Korea are located in rugged mountain area embedding small-scale anomalies. Loop-loop EM survey system can be a better choice for exploring those mines because no ground contact is required and portable loops are freely positioned. Survey design is very important for detecting small amount of mineral deposits efficiently and spatial limits of survey lines should be considered. Along a same survey line, surveys with different separations between a transmitter and a receiver are applicable. EM responses are calculated in a layered-earth model embedding magnetic anomalies and analyses considering electric conductivity and magnetic permeability are made for the loop-loop EM survey data. Combining EM dataset with multi-frequency and multi-separation slightly enhanced a reconstructed image. Loop-loop EM survey using PROMOIS system was conducted on a small magnetite mine. Inversion with and without considering magnetic permeability was conducted for EM data with multi-frequency and multi-separation between a transmitter and a receiver.

  8. Observação do abrilhantamento de limbo solar e de estruturas filamentares em 48 ghz utilizando a técnica de regularização adaptativa

    NASA Astrophysics Data System (ADS)

    Machado, W. R. S.; Mascarenhas, N.; Costa, J. E. R.; Silva, A. V. R.

    2003-08-01

    O radiotelescópio do Itapetinga tem sido utilizado em campanhas de observações de explosões solares gerando um grande número de mapas diários em 48 GHz como sub-produto destas observações. A resolução espacial do telescópio de 14m do Itapetinga nesta freqüência é de aproximadamente dois minutos de arco. Estruturas de interesse para análise da atmosfera solar quiescente tais como os filamentos e o anel de abrilhantamento do limbo são de dimensão angular moderada da ordem ou ligeiramente menores que a resolução do telescópio. É conhecido que a convolução da função de espalhamento do telescópio, PSF (padrão de ganho do feixe) borra as estruturas de dimensão angular abaixo do HPBW (largura a meia potência do feixe) e portanto é comum a busca por técnicas de restauração que eliminem pelo menos em parte este borramento. Estudamos a restauração destas radioimagens usando a técnica de regularização adaptativa e os resultados ressaltam estas estruturas espaciais de pequeno contraste. O algoritmo da regularização adaptativa faz uso de k imagens, chamadas protótipos, obtidas através da variação de parâmetros de um filtro de regularização. Para controle da qualidade da restauração utilizamos uma imagem de alta resolução espacial obtida na linha H-a e a PSF do Itapetinga para borrá-la. Pequenos desvios, entre a PSF utilizada para o borramento e a PSF utilizada na restauração, produziram alguns desvios notáveis na imagem restaurada porém a adição de ruído nas simulações de restauração foram mais influentes no cálculo da rugosidade da imagem e portanto mais limitante para a restauração. Apresentamos como nosso primeiro resultado uma imagem em 48 GHz com a presença clara do abrilhantamento de limbo que não estava evidente na imagem original e traços de estruturas filamentares, porém ainda sem grande evidência.

  9. DOE EM industry programs robotics development

    SciTech Connect

    Staubly, R.; Kothari, V.

    1998-12-31

    The Office of Science and Technology (OST) manages an aggressive program for RD and D, as well as testing and evaluation for the Department of Energy`s (DOE`s) Environmental Management (EM) organization. The goal is to develop new and improved environmental restoration and waste management technologies to clean up the inventory of the DOE weapons complex faster, safer, and cheaper than is possible with currently available technologies. Robotic systems reduce worker exposure to the absolute minimum, while providing proven, cost-effective, and, for some applications, the only acceptable technique for addressing challenging problems. Development of robotic systems for remote operations occurs in three main categories: tank waste characterization and retrieval; decontamination and dismantlement; and characterization, mapping, and inspection systems. In addition, the Federal Energy Technology Center (FETC) has some other projects which fall under the heading of supporting R and D. The central objective of all FETC robotic projects is to make robotic systems more attractive by reducing costs and health risks associated with the deployment of robotic technologies in the cleanup of the nuclear weapons complex. This will be accomplished through development of robots that are cheaper, faster, safer, and more reliable, as well as more straightforward to modify/adapt and more intuitive to operate with autonomous capabilities and intelligent controls that prevent accidents and optimize task execution.

  10. Databases and Archiving for CryoEM.

    PubMed

    Patwardhan, A; Lawson, C L

    2016-01-01

    CryoEM in structural biology is currently served by three public archives-EMDB for 3DEM reconstructions, PDB for models built from 3DEM reconstructions, and EMPIAR for the raw 2D image data used to obtain the 3DEM reconstructions. These archives play a vital role for both the structural community and the wider biological community in making the data accessible so that results may be reused, reassessed, and integrated with other structural and bioinformatics resources. The important role of the archives is underpinned by the fact that many journals mandate the deposition of data to PDB and EMDB on publication. The field is currently undergoing transformative changes where on the one hand high-resolution structures are becoming a routine occurrence while on the other hand electron tomography is enabling the study of macromolecules in the cellular context. Concomitantly the archives are evolving to best serve their stakeholder communities. In this chapter, we describe the current state of the archives, resources available for depositing, accessing, searching, visualizing and validating data, on-going community-wide initiatives and opportunities, and challenges for the future. PMID:27572735

  11. Degradation of Benzodiazepines after 120 Days of EMS Deployment

    PubMed Central

    McMullan, Jason T.; Jones, Elizabeth; Barnhart, Bruce; Denninghoff, Kurt; Spaite, Daniel; Zaleski, Erin; Silbergleit, Robert

    2014-01-01

    Introduction EMS treatment of status epilepticus improves outcomes, but the benzodiazepine best suited for EMS use is unclear, given potential high environmental temperature exposures. Objective To describe the degradation of diazepam, lorazepam, and midazolam as a function of temperature exposure and time over 120 days of storage on active EMS units. Methods Study boxes containing vials of diazepam, lorazepam, and midazolam were distributed to 4 active EMS units in each of 2 EMS systems in the southwestern United States during May–August 2011. The boxes logged temperature every minute and were stored in EMS units per local agency policy. Two vials of each drug were removed from each box at 30-day intervals and underwent high-performance liquid chromatography to determine drug concentration. Concentration was analyzed as mean (and 95%CI) percent of initial labeled concentration as a function of time and mean kinetic temperature (MKT). Results 192 samples were collected (2 samples of each drug from each of 4 units per city at 4 time-points). After 120 days, the mean relative concentration (95%CI) of diazepam was 97.0% (95.7–98.2%) and of midazolam was 99.0% (97.7–100.2%). Lorazepam experienced modest degradation by 60 days (95.6% [91.6–99.5%]) and substantial degradation at 90 days (90.3% [85.2-95.4%]) and 120 days (86.5% [80.7–92.3%]). Mean MKT was 31.6°C (95%CI 27.1–36.1). Increasing MKT was associated with greater degradation of lorazepam, but not midazolam or diazepam. Conclusions Midazolam and diazepam experienced minimal degradation throughout 120 days of EMS deployment in high-heat environments. Lorazepam experienced significant degradation over 120 days and appeared especially sensitive to higher MKT exposure. PMID:24548058

  12. Emergency medical service (EMS): A unique flight environment

    NASA Technical Reports Server (NTRS)

    Shively, R. Jay

    1993-01-01

    The EMS flight environment is unique in today's aviation. The pilots must respond quickly to emergency events and often fly to landing zones where they have never been before . The time from initially receiving a call to being airborne can be as little as two to three minutes. Often the EMS pilot is the only aviation professional on site, they have no operations people or other pilots to aid them in making decisons. Further, since they are often flying to accident scenes, not airports, there is often complete weather and condition information. Therefore, the initial decision that the pilot must make, accepting or declining a flight, can become very difficult. The accident rate of EMS helicopters has been relatively high over the past years. NASA-Ames research center has taken several steps in an attempt to aid EMS pilots in their decision making and situational awareness. A preflight risk assessment system (SAFE) was developed to aid pilots in their decision making, and was tested at an EMS service. The resutls of the study were promising and a second version incorporating the lessons learned is under development. A second line of research was the development of a low cost electronic chart display (ECD). This is a digital map display to help pilots maintain geographical orientation. Another thrust was undertaken in conjunction with the Aviation Safety Reporting System (ASRS). This involved publicizing the ASRS to EMS pilots and personnel, and calling each of the reporters back to gather additional information. This paper will discuss these efforts and how they may positively impact the safety of EMS operations.

  13. Persistent topology for cryo-EM data analysis.

    PubMed

    Xia, Kelin; Wei, Guo-Wei

    2015-08-01

    In this work, we introduce persistent homology for the analysis of cryo-electron microscopy (cryo-EM) density maps. We identify the topological fingerprint or topological signature of noise, which is widespread in cryo-EM data. For low signal-to-noise ratio (SNR) volumetric data, intrinsic topological features of biomolecular structures are indistinguishable from noise. To remove noise, we employ geometric flows that are found to preserve the intrinsic topological fingerprints of cryo-EM structures and diminish the topological signature of noise. In particular, persistent homology enables us to visualize the gradual separation of the topological fingerprints of cryo-EM structures from those of noise during the denoising process, which gives rise to a practical procedure for prescribing a noise threshold to extract cryo-EM structure information from noise contaminated data after certain iterations of the geometric flow equation. To further demonstrate the utility of persistent homology for cryo-EM data analysis, we consider a microtubule intermediate structure Electron Microscopy Data (EMD 1129). Three helix models, an alpha-tubulin monomer model, an alpha-tubulin and beta-tubulin model, and an alpha-tubulin and beta-tubulin dimer model, are constructed to fit the cryo-EM data. The least square fitting leads to similarly high correlation coefficients, which indicates that structure determination via optimization is an ill-posed inverse problem. However, these models have dramatically different topological fingerprints. Especially, linkages or connectivities that discriminate one model from another, play little role in the traditional density fitting or optimization but are very sensitive and crucial to topological fingerprints. The intrinsic topological features of the microtubule data are identified after topological denoising. By a comparison of the topological fingerprints of the original data and those of three models, we found that the third model is

  14. Colloidal Oatmeal <em>(Avena Sativa)em> Improves Skin Barrier Through Multi-Therapy Activity.

    PubMed

    Ilnytska, Olha; Kaur, Simarna; Chon, Suhyoun; Reynertson, Kurt A; Nebus, Judith; Garay, Michelle; Mahmood, Khalid; Southall, Michael D

    2016-06-01

    Oats (Avena sativa) are a centuries-old topical treatment for a variety of skin barrier conditions, including dry skin, skin rashes, and eczema; however, few studies have investigated the actual mechanism of action for the skin barrier strengthening activity of colloidal oatmeal. Four extracts of colloidal oatmeal were prepared with various solvents and tested in vitro for skin barrier related gene expression and activity. Extracts of colloidal oatmeal were found to induce the expression of genes related to epidermal differentiation, tight junctions and lipid regulation in skin, and provide pH-buffering capacity. Colloidal oatmeal boosted the expression of multiple target genes related to skin barrier, and resulted in recovery of barrier damage in an in vitro model of atopic dermatitis. In addition, an investigator-blinded study was performed with 50 healthy female subjects who exhibited bilateral moderate to severe dry skin on their lower legs. Subjects were treated with a colloidal oatmeal skin protectant lotion. Clinically, the colloidal oatmeal lotion showed significant clinical improvements in skin dryness, moisturization, and barrier. Taken together, these results demonstrate that colloidal oatmeal can provide clinically effective benefits for dry and compromised skin by strengthening skin barrier.

    <em>J Drugs Dermatolem>. 2016;15(6):684-690. PMID:27272074

  15. Shallow Magma Accumulation at Halema'uma'u Crater, Kilauea Volcano, Revealed by Microgravity Measurements (1975-2008)

    NASA Astrophysics Data System (ADS)

    Battaglia, M.; Eggers, A.; Bagnardi, M.; Poland, M. P.; Miklius, A.

    2009-12-01

    We examined microgravity data collected during surveys of a dense network around the summit of Kilauea Volcano, Hawai'i, following the 1975 M7.2 earthquake and in 1981, 1998, 2003, and 2008. All gravity measurements are relative to a benchmark located 4 km northwest of the caldera. Gravity changes were adjusted for the free air effect by assuming a correction of -308.6 μGal/m and using leveling data (completed at approximately the same time as the gravity surveys) to determine elevation changes between successive gravity surveys. A several-year time series of water level measurements from a well within Kilauea’s caldera indicates that gravity variations due to groundwater fluctuations are negligible. Residual gravity data are characterized by a prominent positive residual gravity anomaly (an increase of 521 μGal during 1975-2008) along the east margin of Halema'uma'u Crater. The anomaly, which occurs in an area of relatively minor surface deformation, suggests subsurface magma accumulation in void space (probably a network of interconnected cracks) at shallow depths beneath Kilauea's caldera. The region beneath the southeast rim of Halema'uma'u Crater is a known volume of shallow magma storage on the basis of both geodetic and seismic data, and is near the site of several historical summit eruptive vents, including that of the 2008 explosion and subsequent eruption. Assuming a spherical source, we modeled the residual gravity changes measured at stations close to the Halema'uma'u source to estimate the source location, depth and mass change. The weighted least square inversion over the four time periods spanned by the daya gives a depth of 500-950 m (average is 725 m) with a total mass accumulation over 33 years of 6 x 1010 kg. Mass accumulation was variable over 1975-2008, with lower average rates during 1981-1998 and 1998-2003 and higher average rates during 1975-1981 and 2003-2008. The variable accumulation rates are consistent with changes in Kilauea

  16. Learning when to Hold'em and When to Fold'em: ERS's Budget Hold'em Game Facilitates the Budget Development Process in Memphis

    ERIC Educational Resources Information Center

    Education Resource Strategies, 2010

    2010-01-01

    If your school district is facing a budget issue, it might surprise you to learn that the solution might very well lie in a game of cards. That certainly was the case earlier this year for the city schools of Memphis, Tennessee. The game is called Budget Hold'em, and it was developed by Education Resource Strategies (ERS) of Watertown,…

  17. Topical Treatment With an Agent Disruptive to <em>P. acnesem> Biofilm Provides Positive Therapeutic Response: Results of a Randomized Clinical Trial.

    PubMed

    Bernhardt, Michael J; Myntti, Matthew F

    2016-06-01

    The traditional disease model of acne has been one of follicular plugging due to 'sticky epithelial cells' associated with increased sebum production with deep follicular anaerobic conditions favoring <em>P. acnesem>- generated inflammation. <em>P. acnesem> biofilms have been found more frequently in patients with acne than controls. Biofilms are genetically coded to create adhesion to the pilosebaceous unit followed by production of a mucopolysaccharide coating capable of binding to lipid surfaces. Traditional therapies for acne have involved mixtures of oral and topical antibiotics admixed with topical keratolytics and retinoids, which are aimed at traditional bacterial reduction as well as downregulating the inflammatory cascade. These approaches are limited by side effect and compliance/tolerability issues. As the <em>P. acnesem> biofilm may, in fact, be the instigator of this process, we studied the use of a topical agent designed to reduce the <em>P. acnesem> biofilm to see if reducing the biofilm would be therapeutically efficacious. We present data of a proprietary topical non-prescription agent with a novel pharmaco mechanism designed to attack the biofilm produced by <em>P. acnesem>. Our data shows a decrease of inflammatory lesions by 44% and non-inflammatory lesions by 32% after 12 weeks and also provided for a meaningful improvement in the quality of life of the patients in the study. These improvements were achieved with a product that was not associated with burning, chafing, irritation, or erythema, which can be seen with topical treatments. It is apparent from this study that by addressing the biofilm which protects the <em>P. acnesem> bacteria through the use of the Acne Gel, the incidence of acne symptoms can be greatly reduced, while having no negative impacts on the patients' skin (ClinicalTrials.gov registry number NCT02404285).

    <em>J Drugs Dermatol. em>2016;15(6):677-683. PMID:27272073

  18. Refinement of Atomic Structures Against cryo-EM Maps.

    PubMed

    Murshudov, G N

    2016-01-01

    This review describes some of the methods for atomic structure refinement (fitting) against medium/high-resolution single-particle cryo-EM reconstructed maps. Some of the tools developed for macromolecular X-ray crystal structure analysis, especially those encapsulating prior chemical and structural information can be transferred directly for fitting into cryo-EM maps. However, despite the similarities, there are significant differences between data produced by these two techniques; therefore, different likelihood functions linking the data and model must be used in cryo-EM and crystallographic refinement. Although tools described in this review are mostly designed for medium/high-resolution maps, if maps have sufficiently good quality, then these tools can also be used at moderately low resolution, as shown in one example. In addition, the use of several popular crystallographic methods is strongly discouraged in cryo-EM refinement, such as 2Fo-Fc maps, solvent flattening, and feature-enhanced maps (FEMs) for visualization and model (re)building. Two problems in the cryo-EM field are overclaiming resolution and severe map oversharpening. Both of these should be avoided; if data of higher resolution than the signal are used, then overfitting of model parameters into the noise is unavoidable, and if maps are oversharpened, then at least parts of the maps might become very noisy and ultimately uninterpretable. Both of these may result in suboptimal and even misleading atomic models. PMID:27572731

  19. Active geophysical monitoring of hydrocarbon reservoirs using EM methods

    NASA Astrophysics Data System (ADS)

    Gribenko, A.; Black, N.; Zhdanov, M. S.

    2008-12-01

    Marine controlled-source electromagnetic (MCSEM) technology has been successfully established as an effective tool for offshore hydrocarbon (HC) exploration. In this paper we consider another application of the MCSEM method for HC reservoir monitoring. We demonstrate that EM methods can be successfully used for the monitoring of producing wells in connection with the enhanced recovery of hydrocarbons. We have developed a new powerful EM modeling technique based on the integral equation method with an inhomogeneous background conductivity (IE IBC). This new method and the corresponding computer software make it possible to model the EM response over a realistic complex model of a sea-bottom HC reservoir. The numerical modeling results demonstrate that the MCSEM method has the ability to map changes in resistivity caused by the production of hydrocarbons over time. In addition, the EM data help to visualize the changes in the location of the oil-water contact within the reservoir. This result opens the possibility for practical application of the EM method in HC reservoir monitoring.

  20. Application of the EM algorithm to radiographic images.

    PubMed

    Brailean, J C; Little, D; Giger, M L; Chen, C T; Sullivan, B J

    1992-01-01

    The expectation maximization (EM) algorithm has received considerable attention in the area of positron emitted tomography (PET) as a restoration and reconstruction technique. In this paper, the restoration capabilities of the EM algorithm when applied to radiographic images is investigated. This application does not involve reconstruction. The performance of the EM algorithm is quantitatively evaluated using a "perceived" signal-to-noise ratio (SNR) as the image quality metric. This perceived SNR is based on statistical decision theory and includes both the observer's visual response function and a noise component internal to the eye-brain system. For a variety of processing parameters, the relative SNR (ratio of the processed SNR to the original SNR) is calculated and used as a metric to compare quantitatively the effects of the EM algorithm with two other image enhancement techniques: global contrast enhancement (windowing) and unsharp mask filtering. The results suggest that the EM algorithm's performance is superior when compared to unsharp mask filtering and global contrast enhancement for radiographic images which contain objects smaller than 4 mm. PMID:1435595

  1. Breaking Cryo-EM Resolution Barriers to Facilitate Drug Discovery.

    PubMed

    Merk, Alan; Bartesaghi, Alberto; Banerjee, Soojay; Falconieri, Veronica; Rao, Prashant; Davis, Mindy I; Pragani, Rajan; Boxer, Matthew B; Earl, Lesley A; Milne, Jacqueline L S; Subramaniam, Sriram

    2016-06-16

    Recent advances in single-particle cryoelecton microscopy (cryo-EM) are enabling generation of numerous near-atomic resolution structures for well-ordered protein complexes with sizes ≥ ∼200 kDa. Whether cryo-EM methods are equally useful for high-resolution structural analysis of smaller, dynamic protein complexes such as those involved in cellular metabolism remains an important question. Here, we present 3.8 Å resolution cryo-EM structures of the cancer target isocitrate dehydrogenase (93 kDa) and identify the nature of conformational changes induced by binding of the allosteric small-molecule inhibitor ML309. We also report 2.8-Å- and 1.8-Å-resolution structures of lactate dehydrogenase (145 kDa) and glutamate dehydrogenase (334 kDa), respectively. With these results, two perceived barriers in single-particle cryo-EM are overcome: (1) crossing 2 Å resolution and (2) obtaining structures of proteins with sizes < 100 kDa, demonstrating that cryo-EM can be used to investigate a broad spectrum of drug-target interactions and dynamic conformational states. PMID:27238019

  2. International Space Station (ISS) Emergency Mask (EM) Development

    NASA Technical Reports Server (NTRS)

    Toon, Katherine P.; Hahn, Jeffrey; Fowler, Michael; Young, Kevin

    2011-01-01

    The Emergency Mask (EM) is considered a secondary response emergency Personal Protective Equipment (PPE) designed to provide respiratory protection to the International Space Station (ISS) crewmembers in response to a post-fire event or ammonia leak. The EM is planned to be delivered to ISS in 2012 to replace the current air purifying respirator (APR) onboard ISS called the Ammonia Respirator (AR). The EM is a one ]size ]fits ]all model designed to fit any size crewmember, unlike the APR on ISS, and uses either two Fire Cartridges (FCs) or two Commercial Off-the-Shelf (COTS) 3M(Trademark). Ammonia Cartridges (ACs) to provide the crew with a minimum of 8 hours of respiratory protection with appropriate cartridge swap ]out. The EM is designed for a single exposure event, for either post ]fire or ammonia, and is a passive device that cannot help crewmembers who cannot breathe on their own. The EM fs primary and only seal is around the wearer fs neck to prevent a crewmember from inhaling contaminants. During the development of the ISS Emergency Mask, several design challenges were faced that focused around manufacturing a leak free mask. The description of those challenges are broadly discussed but focuses on one key design challenge area: bonding EPDM gasket material to Gore(Registered Trademark) fabric hood.

  3. The 2006/2007 photometric activity of three chromospherically active stars: V2075 Cyg, FG UMa and BM CVn

    NASA Astrophysics Data System (ADS)

    Erdem, A.; Budding, E.; Soydugan, E.; Bakış, H.; Doğru, D.; Doğru, S. S.; Tüysüz, M.; Kaçar, Y.; Dönmez, A.; Soydugan, F.

    2009-08-01

    We present new multiband CCD photometric observations of three chromospherically active stars with long periods (V2075 Cyg, FG UMa and BM CVn). The observations were made at the Çanakkale Onsekiz Mart University Observatory in 2006 and 2007. We analyzed BVRI (Bessell) CCD observations of these three RS CVn-type SB1 binaries with the following three steps: (i) Photometric rotation periods were obtained by analyzing their light variations with a differential corrections method and a Fourier transform technique. (ii) Light variations, observed over three or more consecutive orbital cycles, were investigated by using dark (cool) spot models with the program SPOT. (iii) Surface differential rotation coefficients for the primary components of these binaries were derived using our own photometric periods together with orbital periods taken from the literature.

  4. BVR{sub c}I{sub c} observations and analyses on V2421 Cygni, a precontact W UMa binary

    SciTech Connect

    Samec, R. G.; Shebs, Travis S.; Faulkner, D. R.; Van Hamme, W.; Mathis, R. F.

    2014-01-01

    We present the first precision BVRI light curves, synthetic light curve solutions, and a period study for the high amplitude solar type binary, V2421 Cygni. The light curves have the appearance of an Algol (EA) type; however, it is made up of dwarf solar type components in a detached mode with a period of only 0.6331 days with an amplitude of about a full magnitude, i.e., it is a precontact W UMa binary. Flare-like disruptions occur in the light curves following the primary and secondary eclipses possibly due to the line-of-sight track of a gas stream. An associated stream spot and splash spot cause bright equatorial spots on the stellar surface of the primary star. The more massive star is the gainer, making this system a classic, albeit dwarf, Algol.

  5. Survey of period variations of superhumps in SU UMa-type dwarf novae. VIII. The eighth year (2015-2016)

    NASA Astrophysics Data System (ADS)

    Kato, Taichi; Hambsch, Franz-Josef; Monard, Berto; Vanmunster, Tonny; Maeda, Yutaka; Miller, Ian; Itoh, Hiroshi; Kiyota, Seiichiro; Isogai, Keisuke; Kimura, Mariko; Imada, Akira; Tordai, Tamás; Akazawa, Hidehiko; Tanabe, Kenji; Otani, Noritoshi; Ogi, Minako; Ando, Kazuko; Takigawa, Naoki; Dubovsky, Pavol A.; Kudzej, Igor; Shugarov, Sergey Yu.; Katysheva, Natalia; Golysheva, Polina; Gladilina, Natalia; Chochol, Drahomir; Starr, Peter; Kasai, Kiyoshi; Pickard, Roger D.; Miguel, Enrique de; Kojiguchi, Naoto; Sugiura, Yuki; Fukushima, Daiki; Yamada, Eiji; Uto, Yusuke; Kamibetsunawa, Taku; Tatsumi, Taiki; Takeda, Nao; Matsumoto, Katsura; Cook, Lewis M.; Pavlenko, Elena P.; Babina, Julia V.; Pit, Nikolaj V.; Antonyuk, Oksana I.; Antonyuk, Kirill A.; Sosnovskij, Aleksei A.; Baklanov, Aleksei V.; Kafka, Stella; Stein, William; Voloshina, Irina B.; Ruiz, Javier; Sabo, Richard; Dvorak, Shawn; Stone, Geoff; Andreev, Maksim V.; Antipin, Sergey V.; Zubareva, Alexandra M.; Zaostrojnykh, Anna M.; Richmond, Michael; Shears, Jeremy; Dubois, Franky; Logie, Ludwig; Rau, Steve; Vanaverbeke, Siegfried; Simon, Andrei; Oksanen, Arto; Goff, William N.; Bolt, Greg; Dębski, Bartłomiej; Kochanek, Christopher S.; Shappee, Benjamin; Stanek, Krzysztof Z.; Prieto, José L.; Stubbings, Rod; Muyllaert, Eddy; Hiraga, Mitsutaka; Horie, Tsuneo; Schmeer, Patrick; Hirosawa, Kenji

    2016-07-01

    Continuing the project described by Kato et al. (2009, PASJ, 61, S395), we collected times of superhump maxima for 128 SU UMa-type dwarf novae observed mainly during the 2015-2016 season and characterized these objects. The data have improved the distribution of orbital periods, the relation between the orbital period and the variation of superhumps, and the relation between period variations and the rebrightening type in WZ Sge-type objects. Coupled with new measurements of mass ratios using growing stages of superhumps, we now have a clearer and statistically greatly improved evolutionary path near the terminal stage of evolution of cataclysmic variables. Three objects (V452 Cas, KK Tel, and ASASSN-15cl) appear to have slowly growing superhumps, which is proposed to reflect the slow growth of the 3 : 1 resonance near the stability border. ASASSN-15sl, ASASSN-15ux, SDSS J074859.55+312512.6, and CRTS J200331.3-284941 are newly identified eclipsing SU UMa-type (or WZ Sge-type) dwarf novae. ASASSN-15cy has a short (˜0.050 d) superhump period and appears to belong to EI Psc-type objects with compact secondaries having an evolved core. ASASSN-15gn, ASASSN-15hn, ASASSN-15kh, and ASASSN-16bu are candidate period bouncers with superhump periods longer than 0.06 d. We have newly obtained superhump periods for 79 objects and 13 orbital periods, including periods from early superhumps. In order that future observations will be more astrophysically beneficial and rewarding to observers, we propose guidelines on how to organize observations of various superoutbursts.

  6. Survey of period variations of superhumps in SU UMa-type dwarf novae. VIII. The eighth year (2015-2016)

    NASA Astrophysics Data System (ADS)

    Kato, Taichi; Hambsch, Franz-Josef; Monard, Berto; Vanmunster, Tonny; Maeda, Yutaka; Miller, Ian; Itoh, Hiroshi; Kiyota, Seiichiro; Isogai, Keisuke; Kimura, Mariko; Imada, Akira; Tordai, Tamás; Akazawa, Hidehiko; Tanabe, Kenji; Otani, Noritoshi; Ogi, Minako; Ando, Kazuko; Takigawa, Naoki; Dubovsky, Pavol A.; Kudzej, Igor; Shugarov, Sergey Yu.; Katysheva, Natalia; Golysheva, Polina; Gladilina, Natalia; Chochol, Drahomir; Starr, Peter; Kasai, Kiyoshi; Pickard, Roger D.; Miguel, Enrique de; Kojiguchi, Naoto; Sugiura, Yuki; Fukushima, Daiki; Yamada, Eiji; Uto, Yusuke; Kamibetsunawa, Taku; Tatsumi, Taiki; Takeda, Nao; Matsumoto, Katsura; Cook, Lewis M.; Pavlenko, Elena P.; Babina, Julia V.; Pit, Nikolaj V.; Antonyuk, Oksana I.; Antonyuk, Kirill A.; Sosnovskij, Aleksei A.; Baklanov, Aleksei V.; Kafka, Stella; Stein, William; Voloshina, Irina B.; Ruiz, Javier; Sabo, Richard; Dvorak, Shawn; Stone, Geoff; Andreev, Maksim V.; Antipin, Sergey V.; Zubareva, Alexandra M.; Zaostrojnykh, Anna M.; Richmond, Michael; Shears, Jeremy; Dubois, Franky; Logie, Ludwig; Rau, Steve; Vanaverbeke, Siegfried; Simon, Andrei; Oksanen, Arto; Goff, William N.; Bolt, Greg; Dębski, Bartłomiej; Kochanek, Christopher S.; Shappee, Benjamin; Stanek, Krzysztof Z.; Prieto, José L.; Stubbings, Rod; Muyllaert, Eddy; Hiraga, Mitsutaka; Horie, Tsuneo; Schmeer, Patrick; Hirosawa, Kenji

    2016-08-01

    Continuing the project described by Kato et al. (2009, PASJ, 61, S395), we collected times of superhump maxima for 128 SU UMa-type dwarf novae observed mainly during the 2015-2016 season and characterized these objects. The data have improved the distribution of orbital periods, the relation between the orbital period and the variation of superhumps, and the relation between period variations and the rebrightening type in WZ Sge-type objects. Coupled with new measurements of mass ratios using growing stages of superhumps, we now have a clearer and statistically greatly improved evolutionary path near the terminal stage of evolution of cataclysmic variables. Three objects (V452 Cas, KK Tel, and ASASSN-15cl) appear to have slowly growing superhumps, which is proposed to reflect the slow growth of the 3 : 1 resonance near the stability border. ASASSN-15sl, ASASSN-15ux, SDSS J074859.55+312512.6, and CRTS J200331.3-284941 are newly identified eclipsing SU UMa-type (or WZ Sge-type) dwarf novae. ASASSN-15cy has a short (˜0.050 d) superhump period and appears to belong to EI Psc-type objects with compact secondaries having an evolved core. ASASSN-15gn, ASASSN-15hn, ASASSN-15kh, and ASASSN-16bu are candidate period bouncers with superhump periods longer than 0.06 d. We have newly obtained superhump periods for 79 objects and 13 orbital periods, including periods from early superhumps. In order that future observations will be more astrophysically beneficial and rewarding to observers, we propose guidelines on how to organize observations of various superoutbursts.

  7. A Computerized Evaluation Methodology for Pre-Hospital EMS Cardiac Care

    PubMed Central

    Nagurney, Frank K.

    1980-01-01

    The computerized application of cardiac care protocols for pre-hospital EMS care is presented. The program logic is reviewed and an example of its application is provided. Uses of the results of the program in EMS management are suggested.

  8. EMS Stretcher “Misadventures” in a Large, Urban EMS System: A Descriptive Analysis of Contributing Factors and Resultant Injuries

    PubMed Central

    Goodloe, Jeffrey M.; Crowder, Christopher J.; Arthur, Annette O.; Thomas, Stephen H.

    2012-01-01

    Purpose. There is a paucity of data regarding EMS stretcher-operation-related injuries. This study describes and analyzes characteristics associated with undesirable stretcher operations, with or without resultant injury in a large, urban EMS agency. Methods. In the study agency, all stretcher-related “misadventures” are required to be documented, regardless of whether injury results. All stretcher-related reports between July 1, 2009 and June 30, 2010 were queried in retrospective analysis, avoiding Hawthorne effect in stretcher operations. Results. During the year studied, 129,110 patients were transported. 23 stretcher incidents were reported (0.16 per 1,000 transports). No patient injury occurred. Four EMS providers sustained minor injuries. Among contributing aspects, the most common involved operations surrounding the stretcher-ambulance safety latch, 14/23 (60.9%). From a personnel injury prevention perspective, there exists a significant relationship between combative patients and crew injury related to stretcher operation, Fisher's exact test 0.048. Conclusions. In this large, urban EMS system, the incidence of injury related to stretcher operations in the one-year study period is markedly low, with few personnel injuries and no patient injuries incurred. Safety for EMS personnel and patients could be advanced by educational initiatives that highlight specific events and conditions contributing to stretcher-related adverse events. PMID:22606379

  9. Recent technical advancements enabled atomic resolution CryoEM

    NASA Astrophysics Data System (ADS)

    Xueming, Li

    2016-01-01

    With recent breakthroughs in camera and image processing technologies single-particle electron cryo-microscopy (CryoEM) has suddenly gained the attention of structural biologists as a powerful tool able to solve the atomic structures of biological complexes and assemblies. Compared with x-ray crystallography, CryoEM can be applied to partially flexible structures in solution and without the necessity of crystallization, which is especially important for large complexes and assemblies. This review briefly explains several key bottlenecks for atomic resolution CryoEM, and describes the corresponding solutions for these bottlenecks based on the recent technical advancements. The review also aims to provide an overview about the technical differences between its applications in biology and those in material science. Project supported by Tsinghua-Peking Joint Center for Life Sciences, China.

  10. Virus particle dynamics derived from CryoEM studies.

    PubMed

    Doerschuk, Peter C; Gong, Yunye; Xu, Nan; Domitrovic, Tatiana; Johnson, John E

    2016-06-01

    The direct electron detector has revolutionized electron cryo-microscopy (CryoEM). Icosahedral virus structures are routinely produced at 4Å resolution or better and the approach has largely displaced virus crystallography, as it requires less material, less purity and often produces a structure more rapidly. Largely ignored in this new era of CryoEM is the dynamic information in the data sets that was not available in X-ray structures. Here we review an approach that captures the dynamic character of viruses displayed in the CryoEM ensemble of particles at the moment of freezing. We illustrate the approach with a simple model, briefly describe the details and provide a practical application to virus particle maturation. PMID:27085980

  11. Optimization of ultrasonic/microwave assisted extraction (UMAE) of polysaccharides from Inonotus obliquus and evaluation of its anti-tumor activities.

    PubMed

    Chen, Yiyong; Gu, Xiaohong; Huang, Sheng-quan; Li, Jinwei; Wang, Xin; Tang, Jian

    2010-05-01

    Recently, the use of ultrasonic and microwave has attracted considerable interest as an alternative approach to the traditional extraction methods. In this paper, in order to maximize the yield and purity of polysaccharides from Inonotus obliquus, response surface methodology (RSM) was employed to optimize the ultrasonic/microwave assisted extraction (UMAE) conditions. The results indicated that the optimal conditions for UMAE were 90W microwave power, 50W ultrasonic power together with 40kHz ultrasonic frequency, solid/water ratio was 1:20 (W/V) and the extracting time was 19min, respectively. Under the optimal conditions, the yield and purity of polysaccharides were 3.25% and 73.16%, respectively, which are above that of traditional hot water extraction and close to the predicted value (3.07% and 72.54%, respectively). These results confirmed that ultrasonic/microwave assisted extraction (UMAE) of polysaccharides had great potential and efficiency compared with traditional hot water extraction. At the same time, the anti-tumor activities of the polysaccharides from I. obliquus with UMAE were evaluated. The results suggested that polysaccharides from I. obliquus exhibited obvious anti-tumor activities. PMID:20149817

  12. Geospatial Analysis of Pediatric EMS Run Density and Endotracheal Intubation

    PubMed Central

    Hansen, Matthew; Loker, William; Warden, Craig

    2016-01-01

    Introduction The association between geographic factors, including transport distance, and pediatric emergency medical services (EMS) run clustering on out-of-hospital pediatric endotracheal intubation is unclear. The objective of this study was to determine if endotracheal intubation procedures are more likely to occur at greater distances from the hospital and near clusters of pediatric calls. Methods This was a retrospective observational study including all EMS runs for patients less than 18 years of age from 2008 to 2014 in a geographically large and diverse Oregon county that includes densely populated urban areas near Portland and remote rural areas. We geocoded scene addresses using the automated address locator created in the cloud-based mapping platform ArcGIS, supplemented with manual address geocoding for remaining cases. We then use the Getis-Ord Gi spatial statistic feature in ArcGIS to map statistically significant spatial clusters (hot spots) of pediatric EMS runs throughout the county. We then superimposed all intubation procedures performed during the study period on maps of pediatric EMS-run hot spots, pediatric population density, fire stations, and hospitals. We also performed multivariable logistic regression to determine if distance traveled to the hospital was associated with intubation after controlling for several confounding variables. Results We identified a total of 7,797 pediatric EMS runs during the study period and 38 endotracheal intubations. In univariate analysis we found that patients who were intubated were similar to those who were not in gender and whether or not they were transported to a children’s hospital. Intubated patients tended to be transported shorter distances and were older than non-intubated patients. Increased distance from the hospital was associated with reduced odds of intubation after controlling for age, sex, scene location, and trauma system entry status in a multivariate logistic regression. The

  13. Speaker verification using combined acoustic and EM sensor signal processing

    SciTech Connect

    Ng, L C; Gable, T J; Holzrichter, J F

    2000-11-10

    Low Power EM radar-like sensors have made it possible to measure properties of the human speech production system in real-time, without acoustic interference. This greatly enhances the quality and quantity of information for many speech related applications. See Holzrichter, Burnett, Ng, and Lea, J. Acoustic. SOC. Am . 103 ( 1) 622 (1998). By combining the Glottal-EM-Sensor (GEMS) with the Acoustic-signals, we've demonstrated an almost 10 fold reduction in error rates from a speaker verification system experiment under a moderate noisy environment (-10dB).

  14. Low Bandwidth Vocoding using EM Sensor and Acoustic Signal Processing

    SciTech Connect

    Ng, L C; Holzrichter, J F; Larson, P E

    2001-10-25

    Low-power EM radar-like sensors have made it possible to measure properties of the human speech production system in real-time, without acoustic interference [1]. By combining these data with the corresponding acoustic signal, we've demonstrated an almost 10-fold bandwidth reduction in speech compression, compared to a standard 2.4 kbps LPC10 protocol used in the STU-III (Secure Terminal Unit, third generation) telephone. This paper describes a potential EM sensor/acoustic based vocoder implementation.

  15. Developments in the EM-CCD camera for OGRE

    NASA Astrophysics Data System (ADS)

    Tutt, James H.; McEntaffer, Randall L.; DeRoo, Casey; Schultz, Ted; Miles, Drew M.; Zhang, William; Murray, Neil J.; Holland, Andrew D.; Cash, Webster; Rogers, Thomas; O'Dell, Steve; Gaskin, Jessica; Kolodziejczak, Jeff; Evagora, Anthony M.; Holland, Karen; Colebrook, David

    2014-07-01

    The Off-plane Grating Rocket Experiment (OGRE) is a sub-orbital rocket payload designed to advance the development of several emerging technologies for use on space missions. The payload consists of a high resolution soft X-ray spectrometer based around an optic made from precision cut and ground, single crystal silicon mirrors, a module of off-plane gratings and a camera array based around Electron Multiplying CCD (EM-CCD) technology. This paper gives an overview of OGRE with emphasis on the detector array; specifically this paper will address the reasons that EM-CCDs are the detector of choice and the advantages and disadvantages that this technology offers.

  16. Item Parameter Estimation via Marginal Maximum Likelihood and an EM Algorithm: A Didactic.

    ERIC Educational Resources Information Center

    Harwell, Michael R.; And Others

    1988-01-01

    The Bock and Aitkin Marginal Maximum Likelihood/EM (MML/EM) approach to item parameter estimation is an alternative to the classical joint maximum likelihood procedure of item response theory. This paper provides the essential mathematical details of a MML/EM solution and shows its use in obtaining consistent item parameter estimates. (TJH)

  17. 7 CFR 1945.35 - Special EM loan training.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS...) PROGRAM REGULATIONS (CONTINUED) EMERGENCY Disaster Assistance-General § 1945.35 Special EM loan training. (a) General. When it is evident that a large number of farmers were affected by a widespread...

  18. Reservoir characterization and steam flood monitoring with crosshole EM

    SciTech Connect

    Wilt, M.; Torres-Verdin, C.

    1995-06-01

    Crosshole electromagnetic (EM) imaging is applied to reservoir characterization and steam flood monitoring in a central California oil field. Steam was injected into three stacked eastward-dipping, unconsolidated oil sands within the upper 200 m. The steam plume is expected to develop as an ellipse aligned with the regional northwest-southeast strike. EM measurements were made from two fiberglass-cased observation wells straddling the steam injector on a northeast-southwest profile using the LLNL frequency domain crosshole EM system. Field data were collected before the initiation of a steam drive to map the distribution of the oil sands and then 6 and 12 months later to monitor the progress of the steam chest. Resistivity images derived from the EM data before steam injection clearly delineate the distribution and dipping structure on the target oil sands. Difference images, from data collected before and after steam flooding, show resistivity changes that indicate that the steam chest has developed only in the deeper oil sands although steam injection occurred in all three sand layers.

  19. 7 CFR 1945.20 - Making EM loans available.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 13 2010-01-01 2009-01-01 true Making EM loans available. 1945.20 Section 1945.20 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE SERVICE, RURAL UTILITIES SERVICE, AND FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE...

  20. Functionalized anatomical models for EM-neuron Interaction modeling.

    PubMed

    Neufeld, Esra; Cassará, Antonino Mario; Montanaro, Hazael; Kuster, Niels; Kainz, Wolfgang

    2016-06-21

    The understanding of interactions between electromagnetic (EM) fields and nerves are crucial in contexts ranging from therapeutic neurostimulation to low frequency EM exposure safety. To properly consider the impact of in vivo induced field inhomogeneity on non-linear neuronal dynamics, coupled EM-neuronal dynamics modeling is required. For that purpose, novel functionalized computable human phantoms have been developed. Their implementation and the systematic verification of the integrated anisotropic quasi-static EM solver and neuronal dynamics modeling functionality, based on the method of manufactured solutions and numerical reference data, is described. Electric and magnetic stimulation of the ulnar and sciatic nerve were modeled to help understanding a range of controversial issues related to the magnitude and optimal determination of strength-duration (SD) time constants. The results indicate the importance of considering the stimulation-specific inhomogeneous field distributions (especially at tissue interfaces), realistic models of non-linear neuronal dynamics, very short pulses, and suitable SD extrapolation models. These results and the functionalized computable phantom will influence and support the development of safe and effective neuroprosthetic devices and novel electroceuticals. Furthermore they will assist the evaluation of existing low frequency exposure standards for the entire population under all exposure conditions. PMID:27224508

  1. Functionalized anatomical models for EM-neuron Interaction modeling

    NASA Astrophysics Data System (ADS)

    Neufeld, Esra; Cassará, Antonino Mario; Montanaro, Hazael; Kuster, Niels; Kainz, Wolfgang

    2016-06-01

    The understanding of interactions between electromagnetic (EM) fields and nerves are crucial in contexts ranging from therapeutic neurostimulation to low frequency EM exposure safety. To properly consider the impact of in vivo induced field inhomogeneity on non-linear neuronal dynamics, coupled EM-neuronal dynamics modeling is required. For that purpose, novel functionalized computable human phantoms have been developed. Their implementation and the systematic verification of the integrated anisotropic quasi-static EM solver and neuronal dynamics modeling functionality, based on the method of manufactured solutions and numerical reference data, is described. Electric and magnetic stimulation of the ulnar and sciatic nerve were modeled to help understanding a range of controversial issues related to the magnitude and optimal determination of strength-duration (SD) time constants. The results indicate the importance of considering the stimulation-specific inhomogeneous field distributions (especially at tissue interfaces), realistic models of non-linear neuronal dynamics, very short pulses, and suitable SD extrapolation models. These results and the functionalized computable phantom will influence and support the development of safe and effective neuroprosthetic devices and novel electroceuticals. Furthermore they will assist the evaluation of existing low frequency exposure standards for the entire population under all exposure conditions.

  2. Texas Hold 'em Online Poker: A Further Examination

    ERIC Educational Resources Information Center

    Hopley, Anthony A. B.; Dempsey, Kevin; Nicki, Richard

    2012-01-01

    Playing Texas Hold 'em Online Poker (THOP) is on the rise. However, there is relatively little research examining factors that contribute to problem gambling in poker players. The aim of this study was to extend the research findings of Hopley and Nicki (2010). The negative mood states of depression, anxiety and stress were found to be linked to…

  3. VizieR Online Data Catalog: TU UMa light curves and maxima, CL Aur minima (Liska+, 2016)

    NASA Astrophysics Data System (ADS)

    Liska, J.; Skarka, M.; Mikulasek, Z.; Zejda, M.; Chrastina, M.

    2016-02-01

    Differential photometry for RR Lyrae star TU UMa in the 1st and 2nd file. The measurements were obtained using 24-inch and 1-inch telescopes, respectively. The observations were performed at the Masaryk University Observatory in Brno (3 nights, 24-inch), and at the private observatory in Brno (16 nights, 1-inch) in the Czech Republic from December 2013 to June 2014. Observing equipments consisted of 24-inch Newtonian telescope (600/2780mm, diameter/focal length) and a Moravian Instruments CCD camera G2-4000 with Stromgren photometric filters vby, and of 1-inch refractor (a photographic lens Sonnar 4/135mm, lens focal ratio/focal length) and ATIK 16IC CCD camera with green photometric filter with similar throughput as the Johnson V filter. Exposures were v - 60s, b - 30s, y - 30s, green - 30s. For the small aperture telescope, five frames were combined to a single image to achieve a better signal-to-noise ratio. The time resolution of a such combined frame is about 170s. CCD images were calibrated in a standard way (dark frame and flat field corrections). The C-Munipack software (Motl 2009) was used for this processing as well as for differential photometry. The comparison star BD+30 2165 was the same for both instruments, but the control stars were BD+30 2164 (for the 24-inch telescope) and HD 99593 (for the 1-inch telescope). The 3rd file contains maxima timings of TU UMa adopted from the GEOS RR Lyr database, from the latest publications, together with maxima timings determined in our study. Times of maxima were calculated from our observations, sky-surveys data (Hipparcos, NSVS, Pi of the Sky, SuperWASP), photographic measurements (project DASCH), and from several published datasets, in which the maxima were omitted or badly determined - Boenigk (1958AcA.....8...13B), Liakos, Niarchos (2011IBVS.6099....1L, 2011IBVS.5990....1L), Liu, Janes (1989ApJS...69..593L), Preston et al. (1961ApJ...133..484P). The 4th file contains minima timings of eclipsing binary CL Aur

  4. Detection of the white dwarf and the secondary star in the new SU UMa dwarf nova HS 2219+1824

    NASA Astrophysics Data System (ADS)

    Rodríguez-Gil, P.; Gänsicke, B. T.; Hagen, H.-J.; Marsh, T. R.; Harlaftis, E. T.; Kitsionas, S.; Engels, D.

    2005-02-01

    We report the discovery of a new, non-eclipsing SU UMa-type dwarf nova, HS 2219+1824. Photometry obtained in quiescence (V≈17.5) reveals a double-humped light curve from which we derive an orbital period of ≃86.2 min. Additional photometry obtained during a superoutburst reaching V≃12.0 clearly shows superhumps with a period of ≃89.05 min. The optical spectrum contains double-peaked Balmer and He I emission lines from the accretion disc as well as broad absorption troughs of Hβ, Hγ, and Hδ from the white dwarf primary star. Modelling of the optical spectrum implies a white dwarf temperature of 13 000 K⪉Teff⪉17 000 K, a distance of 180 pc⪉ d⪉230 pc, and suggests that the spectral type of the donor star is later than M 5. Phase-resolved spectroscopy obtained during quiescence reveals a narrow Hα emission line component which has a radial velocity amplitude and phase consistent with an origin on the secondary star, possibly on the irradiated hemisphere facing the white dwarf. This constitutes the first detection of line emission from the secondary star in a quiescent SU UMa star. Based in part on observations obtained at the German-Spanish Astronomical Center, Calar Alto, operated by the Max-Planck-Institut für Astronomie, Heidelberg, jointly with the Spanish National Commission for Astronomy; on observations made with the IAC80 and OGS telescopes, operated on the island of Tenerife by the Instituto de Astrofísica de Canarias (IAC) and the European Space Agency (ESA), respectively, in the Spanish Observatorio del Teide of the IAC; on observations made at the 1.2 m telescope, located at Kryoneri Korinthias, and owned by the National Observatory of Athens, Greece; and on observations made with the William Herschel Telescope, which is operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the IAC.

  5. Airborne EM for geothermal and hydrogeological mapping

    NASA Astrophysics Data System (ADS)

    Menghini, A.; Manzella, A.; Viezzoli, A.; Montanari, D.; Maggi, S.

    2012-12-01

    Within the "VIGOR" project, aimed at assessing the geothermal potential of four regions in southern Italy, Airborne EM data have been acquired, modeled and interpreted. The system deployed was SkyTEM, a time-domain helicopter electromagnetic system designed for hydrogeophysical, environmental and mineral investigations. The AEM data provide, after data acquisition, analysis, processing, and modeling, a distribution volume of electrical resistivity, spanning an investigation depth from ground surface of few hundred meters, depending on resistivity condition. Resistivity is an important physical parameter for geothermal investigation, since it proved to be very effective in mapping anomalies due to hydrothermal fluid circulation, which usually has high salt content and produces clayey alteration minerals. Since the project required, among other issues, to define geothermal resources at shallow level, it was decided to perform a test with an airborne electromagnetic geophysical survey, to verify the advantages offered by the system in covering large areas in a short time. The geophysical survey was carried out in Sicily, Italy, in late 2011, over two test sites named "Termini" and "Western Sicily". The two areas were chosen on different basis. "Termini" area is covered by extensive geological surveys, and was going to be investigated also by means of electrical tomography in its northern part. Since geological condition of Sicily, even at shallow depth, is very complex, this area provided a good place for defining the resistivity values of the main geological units outcropping in the region. "Termini" survey has been also an occasion to define relations between resistivity distribution, lithological units and thermal conductivity. The "Western Sicily" area cover the main thermal manifestations of western Sicily, and the research target was to establish whether they are characterized by common hydrogeological or tectonic features that could be mapped by resistivity

  6. Development of the Emergency Medical Services Role Identity Scale (EMS-RIS).

    PubMed

    Donnelly, Elizabeth A; Siebert, Darcy; Siebert, Carl

    2015-01-01

    This article describes the development and validation of the theoretically grounded Emergency Medical Services Role Identity Scale (EMS-RIS), which measures four domains of EMS role identity. The EMS-RIS was developed using a mixed methods approach. Key informants informed item development and the scale was validated using a representative probability sample of EMS personnel. Factor analyses revealed a conceptually consistent, four-factor solution with sound psychometric properties as well as evidence of convergent and discriminant validities. Social workers work with EMS professionals in crisis settings and as their counselors when they are distressed. The EMS-RIS provides useful information for the assessment of and intervention with distressed EMS professionals, as well as how role identity may influence occupational stress. PMID:25760489

  7. Nonlinear Smoothing and the EM Algorithm for Positive Integral Equations of the First Kind

    SciTech Connect

    Eggermont, P. P. B.

    1999-01-15

    We study a modification of the EMS algorithm in which each step of the EMS algorithm is preceded by a nonlinear smoothing step of the form Nf-exp(S*log f) , where S is the smoothing operator of the EMS algorithm. In the context of positive integral equations (a la positron emission tomography) the resulting algorithm is related to a convex minimization problem which always admits a unique smooth solution, in contrast to the unmodified maximum likelihood setup. The new algorithm has slightly stronger monotonicity properties than the original EM algorithm. This suggests that the modified EMS algorithm is actually an EM algorithm for the modified problem. The existence of a smooth solution to the modified maximum likelihood problem and the monotonicity together imply the strong convergence of the new algorithm. We also present some simulation results for the integral equation of stereology, which suggests that the new algorithm behaves roughly like the EMS algorithm.

  8. GPS computer navigators to shorten EMS response and transport times.

    PubMed

    Ota, F S; Muramatsu, R S; Yoshida, B H; Yamamoto, L G

    2001-05-01

    GPS (global positioning satellite system to determine one's position on earth) units have become inexpensive and compact. The purpose of this study is to assess the effectiveness of a GPS enhanced computer street map navigator to improve the ability of EMS drivers in an urban setting to locate their destination and shorten response times. For part I, residential addresses in the city were randomly selected from a telephone directory. Two driver/navigator teams were assigned to drive to the address adhering to speed limits. One team used a standard street map, whereas the other team used a GPS computer navigator. The travel time and distance of the runs were compared. For part II, the computer GPS navigator was placed on an ambulance to supplement their normal methods of navigation to find the address requesting EMS. After the run was completed, EMS providers were interviewed to determine their opinion of whether the GPS navigator was helpful. For part I the results showed that in the 29 initial test runs, comparing the GPS team versus the standard map team, the mean distances traveled were 8.7 versus 9.0 kilometers (not significant) and the mean travel times were 13.5 versus 14.6 minutes (P=.02), respectively. The GPS team arrived faster in 72% runs. For part II the results showed that most EMS providers surveyed noted that the GPS computer navigator enhanced their ability to find the destination and all EMS providers acknowledged that it would enhance their ability to find a destination in an area in which they were unfamiliar. These results suggest that a portable GPS computer navigator system is helpful and can enhance the ability of prehospital care providers to locate their destination. Because these units are accurate and inexpensive, GPS computer navigators may be a valuable tool in reducing pre-hospital transport times. PMID:11326345

  9. The B and Be States of the Star EM Cepheus

    NASA Astrophysics Data System (ADS)

    Kjurkchieva, Diana; Marchev, Dragomir; Sigut, T. A. A.; Dimitrov, Dinko

    2016-09-01

    We present 11 yr of high-resolution, spectroscopic observations for the star EM Cep. EM Cep switches between B and Be star states, as revealed by the level of Hα emission, but spends most of its time in the B star state. EM Cep has been considered to be an eclipsing, near-contact binary of nearly equal-mass B stars in order to reproduce regular photometric variations; however, this model is problematic due to the lack of any observed Doppler shift in the spectrum. Our observations confirm that there are no apparent Doppler shifts in the wide spectral lines Hα and He i λ6678 in either the B or Be star states. The profiles of He i λ6678 typically exhibited a filled-in absorption core, but we detected weak emission in this line during the highest Be state. Given the lack of observed Doppler shifts, we model EM Cep as an isolated Be star with a variable circumstellar disk. We can reproduce the observed Hα emission profiles over the 11 yr period reasonably well with disk masses on the order of 3{--}10× {10}-11 {M}* in the Be state with the circumstellar disk seen at an inclination of 78° to the line of sight. From a disk ejection episode in 2014, we estimate a mass-loss rate of ≈ 3× {10}-9 {M}ȯ {{yr}}-1. The derived disk density parameters are typical of those found for the classical Be stars. We therefore suggest that the EM Cep is a classical Be star and that its photometric variations are the result of β Cep or nonradial pulsations.

  10. Similarity-regulation of OS-EM for accelerated SPECT reconstruction.

    PubMed

    Vaissier, P E B; Beekman, F J; Goorden, M C

    2016-06-01

    Ordered subsets expectation maximization (OS-EM) is widely used to accelerate image reconstruction in single photon emission computed tomography (SPECT). Speedup of OS-EM over maximum likelihood expectation maximization (ML-EM) is close to the number of subsets used. Although a high number of subsets can shorten reconstruction times significantly, it can also cause severe image artifacts such as improper erasure of reconstructed activity if projections contain few counts. We recently showed that such artifacts can be prevented by using a count-regulated OS-EM (CR-OS-EM) algorithm which automatically adapts the number of subsets for each voxel based on the estimated number of counts that the voxel contributed to the projections. While CR-OS-EM reached high speed-up over ML-EM in high-activity regions of images, speed in low-activity regions could still be very slow. In this work we propose similarity-regulated OS-EM (SR-OS-EM) as a much faster alternative to CR-OS-EM. SR-OS-EM also automatically and locally adapts the number of subsets, but it uses a different criterion for subset regulation: the number of subsets that is used for updating an individual voxel depends on how similar the reconstruction algorithm would update the estimated activity in that voxel with different subsets. Reconstructions of an image quality phantom and in vivo scans show that SR-OS-EM retains all of the favorable properties of CR-OS-EM, while reconstruction speed can be up to an order of magnitude higher in low-activity regions. Moreover our results suggest that SR-OS-EM can be operated with identical reconstruction parameters (including the number of iterations) for a wide range of count levels, which can be an additional advantage from a user perspective since users would only have to post-filter an image to present it at an appropriate noise level. PMID:27206135

  11. Similarity-regulation of OS-EM for accelerated SPECT reconstruction

    NASA Astrophysics Data System (ADS)

    Vaissier, P. E. B.; Beekman, F. J.; Goorden, M. C.

    2016-06-01

    Ordered subsets expectation maximization (OS-EM) is widely used to accelerate image reconstruction in single photon emission computed tomography (SPECT). Speedup of OS-EM over maximum likelihood expectation maximization (ML-EM) is close to the number of subsets used. Although a high number of subsets can shorten reconstruction times significantly, it can also cause severe image artifacts such as improper erasure of reconstructed activity if projections contain few counts. We recently showed that such artifacts can be prevented by using a count-regulated OS-EM (CR-OS-EM) algorithm which automatically adapts the number of subsets for each voxel based on the estimated number of counts that the voxel contributed to the projections. While CR-OS-EM reached high speed-up over ML-EM in high-activity regions of images, speed in low-activity regions could still be very slow. In this work we propose similarity-regulated OS-EM (SR-OS-EM) as a much faster alternative to CR-OS-EM. SR-OS-EM also automatically and locally adapts the number of subsets, but it uses a different criterion for subset regulation: the number of subsets that is used for updating an individual voxel depends on how similar the reconstruction algorithm would update the estimated activity in that voxel with different subsets. Reconstructions of an image quality phantom and in vivo scans show that SR-OS-EM retains all of the favorable properties of CR-OS-EM, while reconstruction speed can be up to an order of magnitude higher in low-activity regions. Moreover our results suggest that SR-OS-EM can be operated with identical reconstruction parameters (including the number of iterations) for a wide range of count levels, which can be an additional advantage from a user perspective since users would only have to post-filter an image to present it at an appropriate noise level.

  12. Projeto educação em ciências com observatórios virtuais: a participação da Escola Moppe no período 2000-2003

    NASA Astrophysics Data System (ADS)

    Wuensche, C. A.; Gavioli, E.; Oliveira, A. L. P. R. S.; da Silva, C.; Cardoso, H. P.; Estácio, S.

    2003-08-01

    O projeto Educação em Ciências com Observatórios Virtuais foi concebido pelo Instituto Astronômico e Geofísico da USP, agregando diversas instituições de ensino e pesquisa no país para desenvolver competências diversas na educação fundamental, média e superior utilizando a astronomia como ferramenta multidisciplinar. Este trabalho descreve a participação da MOPPE, escola-piloto do INPE no projeto, no período de 2000-2003. Serão apresentadas 1) a criação de um clube de ciências (1999 a 2001) cujo tema foi a colonização de Marte e 2) a ementa de astronomia trabalhada com as 7a. e 8a. séries do ensino fundamental. A proposta do projeto Colonizando Marte foi estudar diversos aspectos de uma missão interplanetária e construir experiementos que permitissem quantificar esses aspectos. Os resultados obtidos incluiram apresentações nas SBPC Jovem em 2000 e 2001. Discutiremos também as ementas de astronomia trabalhadas desde 2001 e o envolvimento dos alunos com atividades ligadas a astronomia, fora da aula de ciências. A inclusão de astronomia no currículo das últimas séries motivou a participação de mais alunos culminando com a conquista de duas medalhas para alunos da 7a. série na Olimpiada Brasileira de Astronomia em 2002. Houve também um aumento no número de participantes na OBA 2003 e nos projetos de astronomia mais elaborados nas Feira de Ciências de 2001 e 2002. Destacamos em 2003 a inclusão da MOPPE no projeto TIE - Telescopes in Education - da NASA, que utiliza o telescópio do Observatório de Mount Wilson (EUA) para observações remotas em projetos pedagógicos para o ensino de astronomia.

  13. First BVR light curves and preliminary results of a recently discovered W UMa-type binary: V1848 Ori

    NASA Astrophysics Data System (ADS)

    Kriwattanawong, W.; Poojon, P.

    2014-04-01

    First complete photometric light curves of a recently discovered contact binary, V1848 Ori, are presented. BVR imaging data were used to derive photometric solutions, using Wilson-Devinney code. We discovered that this system is a weak-contact binary, with a fillout factor of f = 13.14%(±1.44%). Preliminary results showed that V1848 Ori is an A-type W UMa system, with a mass ratio of q = 0.7615. The more massive component was found about 400 K hotter than the other one. This system has varied from W-type to A-type during the last decade. According to the preliminary physical parameters, the weak-contact configuration of this system, with the mass ratio close to unity, and no sign of long-term orbital period change yet, is unlikely to be broken. The contact configuration is expected to be maintained and become deeper or not, depending on effect of the AML mechanism.

  14. The first photometric analysis and period investigation of the W UMa type binary system V1139 Cas

    NASA Astrophysics Data System (ADS)

    Li, K.; Hu, S.-M.; Guo, D.-F.; Jiang, Y.-G.; Gao, D.-Y.; Chen, X.

    2015-01-01

    V1139 Cas, which is a very short period W UMa type binary star, was a neglected object since its discovery. BVRI light curves of this system observed using the 1 m telescope at Weihai Observatory of Shandong University are presented and are analyzed using the Wilson-Devinney code. It is discovered that V1139 Cas is a shallow contact binary system (f=3.6%) with a mass ratio of q=1.583. By using all available times of minimum light, the orbital period variation is studied for the first time. We found that the orbital period has varied by a combination of an downward parabola and a sinusoid. The downward parabola means continuous period decrease at a rate of dP/dt=3.66×10-7 d yr-1 and may be caused by angular momentum loss via stellar wind. The sinusoidal variation with a period of 12.8 yr and a semi-amplitude of 0.0064 days can most likely be interpreted as the light travel time effect due to the existence of an unseen tertiary companion.

  15. Photometric studies of two W UMa type variables in the field of distant open cluster NGC 6866

    NASA Astrophysics Data System (ADS)

    Joshi, Yogesh Chandra; Jagirdar, Rukmini; Joshi, Santosh

    2016-04-01

    We present photometric analysis of the two W UMa type binaries identified in the field of distant open star cluster NGC 6866. Although these systems, namely ID487 and ID494, were reported by Joshi et al., a detailed study of these stars has not been carried out before. The orbital periods of these stars are found to be 0.415110±0.000001 day and 0.366709±0.000004 day, respectively. Based on the photometric and infrared colors, we find their respective spectral types to be K0 and K3. The photometric light variations of both stars show the O'Connell effect which can be explained by employing a dark spot on the secondary components. The V and I band light curves are analyzed using the Wilson-Devinney (WD) code and relations given by Gazeas which yield radii and masses for the binary components of star ID487 of R1 = 1.24 ± 0.01 R⊙, R2 = 1.11 ± 0.02 R⊙, and M1 = 1.24 ± 0.02 M⊙, M2 = 0.96 ± 0.05 M⊙ and for star ID494 of R1 = 1.22±0.02R⊙, R2 = 0.81±0.01 R⊙, and M1 = 1.20±0.06 M⊙, M2 = 0.47±0.01 M⊙.

  16. Speciation, population structure, and demographic history of the Mojave Fringe-toed Lizard (Uma scoparia), a species of conservation concern.

    PubMed

    Gottscho, Andrew D; Marks, Sharyn B; Jennings, W Bryan

    2014-06-01

    The North American deserts were impacted by both Neogene plate tectonics and Quaternary climatic fluctuations, yet it remains unclear how these events influenced speciation in this region. We tested published hypotheses regarding the timing and mode of speciation, population structure, and demographic history of the Mojave Fringe-toed Lizard (Uma scoparia), a sand dune specialist endemic to the Mojave Desert of California and Arizona. We sampled 109 individual lizards representing 22 insular dune localities, obtained DNA sequences for 14 nuclear loci, and found that U. scoparia has low genetic diversity relative to the U. notata species complex, comparable to that of chimpanzees and southern elephant seals. Analyses of genotypes using Bayesian clustering algorithms did not identify discrete populations within U. scoparia. Using isolation-with-migration (IM) models and a novel coalescent-based hypothesis testing approach, we estimated that U. scoparia diverged from U. notata in the Pleistocene epoch. The likelihood ratio test and the Akaike Information Criterion consistently rejected nested speciation models that included parameters for migration and population growth of U. scoparia. We reject the Neogene vicariance hypothesis for the speciation of U. scoparia and define this species as a single evolutionarily significant unit for conservation purposes. PMID:25360285

  17. Speciation, population structure, and demographic history of the Mojave Fringe-toed Lizard (Uma scoparia), a species of conservation concern

    PubMed Central

    Gottscho, Andrew D; Marks, Sharyn B; Jennings, W Bryan

    2014-01-01

    The North American deserts were impacted by both Neogene plate tectonics and Quaternary climatic fluctuations, yet it remains unclear how these events influenced speciation in this region. We tested published hypotheses regarding the timing and mode of speciation, population structure, and demographic history of the Mojave Fringe-toed Lizard (Uma scoparia), a sand dune specialist endemic to the Mojave Desert of California and Arizona. We sampled 109 individual lizards representing 22 insular dune localities, obtained DNA sequences for 14 nuclear loci, and found that U. scoparia has low genetic diversity relative to the U. notata species complex, comparable to that of chimpanzees and southern elephant seals. Analyses of genotypes using Bayesian clustering algorithms did not identify discrete populations within U. scoparia. Using isolation-with-migration (IM) models and a novel coalescent-based hypothesis testing approach, we estimated that U. scoparia diverged from U. notata in the Pleistocene epoch. The likelihood ratio test and the Akaike Information Criterion consistently rejected nested speciation models that included parameters for migration and population growth of U. scoparia. We reject the Neogene vicariance hypothesis for the speciation of U. scoparia and define this species as a single evolutionarily significant unit for conservation purposes. PMID:25360285

  18. Tephra deposits of impulsive explosive events during the 2008 eruption of Halema`uma`u Crater, Kilauea

    NASA Astrophysics Data System (ADS)

    Houghton, B. F.; Swanson, D.; Carey, R. J.; Rausch, J.

    2010-12-01

    Eight short-lived impulsive explosive eruptions of low intensity occurred at Halema`uma`u crater, Kilauea in March-October 2008. Estimated total erupted masses were 10E+5 to 10E+6 kg; using inferred durations of 20-50 s, these equate to eruption rates of c. 10E+3 to 10E+4 kg/s, an order of magnitude lower than typical sustained Hawaiian fountains of the 20th century. Deposits are predominantly lapilli-sized but generally contain two elements: near-circular aprons of ballistic blocks extending to 200-400 m from the vent and wind-attenuated convective fall lobes which extend several tens of kilometers downwind but barely reach single-clast thickness even along the dispersal axes. Thinning half-distances (bt) for the deposits are 10-90 m, consistent with the exceptionally low mass discharges and similar to those of mild Strombolian eruptions. This geometry is essentially cone-like (and consistent with the low discharge rates) but the short duration of the events means no permanent deposit has formed. The deposits are relatively well-sorted yet richer in wall rock than the products of typical Hawaiian or Strombolian explosions.

  19. DEZ ANOS DE EXPERIÊNCIA DO COMITÊ DE ÉTICA EM PESQUISA DA SECRETARIA DE SAÚDE DO DISTRITO FEDERAL, BRASIL

    PubMed Central

    Novaes, Maria Rita C. G.; Guilhem, Dirce; Lolas, Fernando

    2009-01-01

    O objetivo deste artigo é relatar a experiência do Comitê de Ética em Pesquisa da Secretaria de Estado de Saúde do Distrito Federal (CEP/SES/DF) Brasil, durante o período de 10 anos a partir de sua fundação. Trata-se de uma avaliação descritiva e documental, na modalidade estudo de caso, utilizando-se a totalidade de projetos protocolados no CEP/SES/DF (N° 052/08) nesse período. As pendências mais freqüentes dos projetos foram: termo de consentimento livre e esclarecido (30%), folha de rosto (25%), metodologia (20%), curriculum vitae (12%), planilha de orçamento (9%), outros (4%). O relato das atividades do CEP/SES/DF no período de 10 anos revelou, através de sua produtividade, a legitimidade do processo de análise ética dos protocolos visando à proteção dos participantes da pesquisa. PMID:19888441

  20. The orbital period of the dwarf nova HS Virginis, the revised Po-Ps relation and the ``superhump" mass ratio distribution of SU UMa stars

    NASA Astrophysics Data System (ADS)

    Mennickent, R. E.; Matsumoto, K.; Arenas, J.

    1999-08-01

    A spectroscopic study of the SU UMa star HS Vir is presented. From the analysis of the radial velocities of the Hα emission line the most likely orbital period is 0\\fd07692(3), although we cannot discard two aliases at 0\\fd07678 and 0\\fd07709. The Balmer lines follow the orbital period with a radial velocity semiamplitude K = 96 +/- 9 km s(-1) , but the He I lambda 5875 emission line shows a double wave during the orbital cycle. We found that the mean Balmer, He I and He II 4686 lines can be roughly modeled with a disk radial emissivity ~ r(-2) . A revised version of the Po-Ps relation for SU UMa stars is also given, which is relevant for discriminating between +/- 1 c/d aliases of the orbital period. We calculated the mass ratio, derived from the tidal resonance model, of HS Vir (qsh = 0.22 +/- 0.04) and 43 additional SU UMa stars. The qsh distribution has a roughly gaussian shape with a mean 0.14, in sharp contrast with the orbital period distribution. Finally, a discussion of the possible stellar masses and inclination of HS Vir is given. We observe that the mass ratio derived from the dynamic solution is in disagreement with that derived from the tidal resonance model. This fact probably indicates that K does not represent the white dwarf binary motion. Based on observations obtained at ESO La Silla Observatory (ESO Proposal 61.D-0395).

  1. Service Discovery Framework Supported by EM Algorithm and Bayesian Classifier

    NASA Astrophysics Data System (ADS)

    Peng, Yanbin

    Service oriented computing has become the main stream research field nowadays. Meanwhile, machine learning is a promising AI technology which can enhance the performance of traditional algorithm. Therefore, aiming at solving service discovery problem, this paper imports Bayesian classifier to web service discovery framework, which can improve service querying speed. In this framework, services in service library become training set of Bayesian classifier, service query becomes a testing sample. Service matchmaking process can be executed in related service class, which has fewer services, thus can save time. Due to don't know the class of service in training set, EM algorithm is used to estimate prior probability and likelihood functions. Experiment results show that the EM algorithm and Bayesian classifier supported method outperforms other methods in time complexity.

  2. Magen David Adom--the EMS in Israel.

    PubMed

    Ellis, Daniel Y; Sorene, Eliot

    2008-01-01

    Israel is a small country with a population of around 7 million. The sole EMS provider for Israel is Magen David Adom (MDA) (translated as 'Red Shield of David'). MDA also carries out the functions of a National Society (similar to the Red Cross) and provides all the blood and blood product services for the country. Nationwide, the organisation responds to over 1000 emergency calls a day and uses doctors, paramedics, emergency medical technicians and volunteers. Local geopolitics has meant that MDA has to be prepared for anything from everyday emergency calls to suicide bombings and regional wars. MDA also prides itself in being able to rapidly assemble and dispatch mobile aid teams to scenes of international disasters. Such a broad range of activities is unusual for a single EMS organisation. PMID:17767990

  3. Superconducting Electromagnetic Suspension (EMS) system for Grumman Maglev concept

    NASA Technical Reports Server (NTRS)

    Kalsi, Swarn S.

    1994-01-01

    The Grumman developed Electromagnetic Suspension (EMS) Maglev system has the following key characteristics: a large operating airgap--40 mm; levitation at all speeds; both high speed and low speed applications; no deleterious effects on SC coils at low vehicle speeds; low magnetic field at the SC coil--less than 0.35 T; no need to use non-magnetic/non-metallic rebar in the guideway structure; low magnetic field in passenger cabin--approximately 1 G; low forces on the SC coil; employs state-of-the-art NbTi wire; no need for an active magnet quench protection system; and lower weight than a magnet system with copper coils. The EMS Maglev described in this paper does not require development of any new technologies. The system could be built with the existing SC magnet technology.

  4. Environmental Restoration and Waste Management (EM) program: An introduction

    SciTech Connect

    Not Available

    1990-12-01

    This booklet introduces the reader to the mission and functions of a major new unit within the US Department of Energy (DOE): the Office of Environmental Restoration and Waste Management (EM). The Secretary of Energy established EM in November 1989, implementing a central purpose of DOE's first annual Environmental Restoration and Waste Management Five-Year Plan, which had appeared three months earlier. The contents of this booklet, and their arrangement, reflect the annual update of the Five-Year Plan. The Five-Year Plan supports DOE's strategy for meeting its 30-year compliance and cleanup goal. This strategy involves: focusing DOE's activities on eliminating or reducing known or recognized potential risks to worker and public health and the environment, containing or isolating, removing, or detoxifying onsite and offsite contamination, and developing technology to achieve DOE's environmental goals.

  5. Generalized single-particle cryo-EM--a historical perspective.

    PubMed

    Frank, Joachim

    2016-02-01

    This is a brief account of the earlier history of single-particle cryo-EM of biological molecules lacking internal symmetry, which goes back to the mid-seventies. The emphasis of this review is on the mathematical concepts and computational approaches. It is written as the field experiences a turning point in the wake of the introduction of digital cameras capable of single electron counting, and near-atomic resolution can be reached even for smaller molecules. PMID:26566976

  6. Environmental differences in substrate mechanics do not affect sprinting performance in sand lizards (Uma scoparia and Callisaurus draconoides).

    PubMed

    Korff, Wyatt L; McHenry, Matthew J

    2011-01-01

    Running performance depends on a mechanical interaction between the feet of an animal and the substrate. This interaction may differ between two species of sand lizard from the Mojave Desert that have different locomotor morphologies and habitat distributions. Uma scorparia possesses toe fringes and inhabits dunes, whereas the closely related Callisaurus draconoides lacks fringes and is found on dune and wash habitats. The present study evaluated whether these distribution patterns are related to differential locomotor performance on the fine sand of the dunes and the course sand of the wash habitat. We measured the kinematics of sprinting and characterized differences in grain size distribution and surface strength of the soil in both habitats. Although wash sand had a surface strength (15.4±6.2 kPa) that was more than three times that of dune sand (4.7±2.1 kPa), both species ran with similar sprinting performance on the two types of soil. The broadly distributed C. draconoides ran with a slightly (22%) faster maximum speed (2.2±0.2 m s(-1)) than the dune-dwelling U. scorparia (1.8±0.2 m s(-1)) on dune sand, but not on wash sand. Furthermore, there were no significant differences in maximum acceleration or the time to attain maximum speed between species or between substrates. These results suggest that differences in habitat distribution between these species are not related to locomotor performance and that sprinting ability is dominated neither by environmental differences in substrate nor the presence of toe fringes. PMID:21147976

  7. EMS-STARS: Emergency Medical Services "Superuser" Transport Associations: An Adult Retrospective Study.

    PubMed

    Hall, M Kennedy; Raven, Maria C; Hall, Jane; Yeh, Clement; Allen, Elaine; Rodriguez, Robert M; Tangherlini, Niels L; Sporer, Karl A; Brown, John F

    2015-01-01

    Abstract Objective. Emergency medical services (EMS) "superusers" -those who use EMS services at extremely high rates -have not been well characterized. Recent interest in the small group of individuals who account for a disproportionate share of health-care expenditures has led to research on frequent users of emergency departments and other health services, but little research has been done regarding those who use EMS services. To inform policy and intervention implementation, we undertook a descriptive analysis of EMS superusers in a large urban community. In this paper we compare EMS superusers to low, moderate, and high users to characterize factors contributing to EMS use. We also estimate the financial impact of EMS superusers. Methods. We conducted a retrospective cross-sectional study based on 1 year of data from an urban EMS system. Data for all EMS encounters with patients age ≥18 years were extracted from electronic records generated on scene by paramedics. We identified demographic and clinical variables associated with levels of EMS use. EMS users were characterized by the annual number of EMS encounters: low (1), moderate (2-4), high (5-14), and superusers (≥15). In addition, we performed a financial analysis using San Francisco Fire Department (SFFD) 2009 charge and reimbursement data. Results. A total of 31,462 adults generated 43,559 EMS ambulance encounters, which resulted in 39,107 transports (a 90% transport rate). Encounters for general medical reasons were common among moderate and high users and less frequent among superusers and low users, while alcohol use was exponentially correlated with encounter frequency. Superusers were significantly younger than moderate EMS users, and more likely to be male. The superuser group created a significantly higher financial burden/person than any other group, comprising 0.3% of the study population, but over 6% of annual EMS charges and reimbursements. Conclusions. In this retrospective study, adult

  8. Improving EM&V for Energy Efficiency Programs (Fact Sheet)

    SciTech Connect

    Not Available

    2012-07-01

    This fact sheet describes the objectives of the U.S. Department of Energy Uniform Methods Project to bring consistency to energy savings calculations in U.S. energy efficiency programs. The U.S. Department of Energy (DOE) is developing a framework and a set of protocols for determining gross energy savings from energy efficiency measures and programs. The protocols represent a refinement of the body of knowledge supporting energy efficiency evaluation, measurement, and verification (EM&V) activities. They have been written by technical experts within the field and reviewed by industry experts. Current EM&V practice allows for multiple methods for calculating energy savings. These methods were developed to meet the needs of energy efficiency program administrators and regulators. Although they served their original objectives well, they have resulted in inconsistent and incomparable savings results - even for identical measures. The goal of the Uniform Methods Project is to strengthen the credibility of energy savings determinations by improving EM&V, increasing the consistency and transparency of how energy savings are determined.

  9. The US DOE-EM International Program - 13004

    SciTech Connect

    Elmetti, Rosa R.; Han, Ana M.; Williams, Alice C.

    2013-07-01

    The U.S. Department of Energy (DOE) Office of Environmental Management (EM) conducts international collaboration activities in support of U.S. policies and objectives regarding the accelerated risk reduction and remediation of environmental legacy of the nations' nuclear weapons program and government sponsored nuclear energy research. The EM International Program supported out of the EM Office of the Associate Principal Deputy Assistant Secretary pursues collaborations with foreign government organizations, educational institutions and private industry to assist in identifying technologies and promote international collaborations that leverage resources and link international experience and expertise. In fiscal year (FY) 2012, the International Program awarded eight international collaborative projects for work scope spanning waste processing, groundwater and soil remediation, deactivation and decommissioning (D and D) and nuclear materials disposition initiatives to seven foreign organizations. Additionally, the International Program's scope and collaboration opportunities were expanded to include technical as well as non-technical areas. This paper will present an overview of the on-going tasks awarded in FY 2012 and an update of upcoming international activities and opportunities for expansion into FY 2013 and beyond. (authors)

  10. Volta phase plate cryo-EM of the small protein complex Prx3.

    PubMed

    Khoshouei, Maryam; Radjainia, Mazdak; Phillips, Amy J; Gerrard, Juliet A; Mitra, Alok K; Plitzko, Jürgen M; Baumeister, Wolfgang; Danev, Radostin

    2016-01-01

    Cryo-EM of large, macromolecular assemblies has seen a significant increase in the numbers of high-resolution structures since the arrival of direct electron detectors. However, sub-nanometre resolution cryo-EM structures are rare compared with crystal structure depositions, particularly for relatively small particles (<400 kDa). Here we demonstrate the benefits of Volta phase plates for single-particle analysis by time-efficient cryo-EM structure determination of 257 kDa human peroxiredoxin-3 dodecamers at 4.4 Å resolution. The Volta phase plate improves the applicability of cryo-EM for small molecules and accelerates structure determination. PMID:26817416

  11. Standard errors for EM estimates in generalized linear models with random effects.

    PubMed

    Friedl, H; Kauermann, G

    2000-09-01

    A procedure is derived for computing standard errors of EM estimates in generalized linear models with random effects. Quadrature formulas are used to approximate the integrals in the EM algorithm, where two different approaches are pursued, i.e., Gauss-Hermite quadrature in the case of Gaussian random effects and nonparametric maximum likelihood estimation for an unspecified random effect distribution. An approximation of the expected Fisher information matrix is derived from an expansion of the EM estimating equations. This allows for inferential arguments based on EM estimates, as demonstrated by an example and simulations. PMID:10985213

  12. Modeling of MHD edge containment in strip casting with ELEKTRA and CaPS-EM codes

    SciTech Connect

    Chang, F. C.

    2000-01-12

    This paper presents modeling studies of magnetohydrodynamics analysis in twin-roll casting. Argonne National Laboratory (ANL) and ISPAT Inland Inc. (Inland), formerly Inland Steel Co., have worked together to develop a three-dimensional (3-D) computer model that can predict eddy currents, fluid flows, and liquid metal containment of an electromagnetic (EM) edge containment device. The model was verified by comparing predictions with experimental results of liquid metal containment and fluid flow in EM edge dams (EMDs) that were designed at Inland for twin-roll casting. This mathematical model can significantly shorten casting research on the use of EM fields for liquid metal containment and control. The model can optimize the EMD design so it is suitable for application, and minimize expensive time-consuming full-scale testing. Numerical simulation was performed by coupling a 3-D finite-element EM code (ELEKTRA) and a 3-D finite-difference fluids code (CaPS-EM) to solve heat transfer, fluid flow, and turbulence transport in a casting process that involves EM fields. ELEKTRA can predict the eddy-current distribution and the EM forces in complex geometries. CaPS-EM can model fluid flows with free surfaces. The computed 3-D magnetic fields and induced eddy currents in ELEKTRA are used as input to temperature- and flow-field computations in CaPS-EM. Results of the numerical simulation compared well with measurements obtained from both static and dynamic tests.

  13. Volta phase plate cryo-EM of the small protein complex Prx3

    NASA Astrophysics Data System (ADS)

    Khoshouei, Maryam; Radjainia, Mazdak; Phillips, Amy J.; Gerrard, Juliet A.; Mitra, Alok K.; Plitzko, Jürgen M.; Baumeister, Wolfgang; Danev, Radostin

    2016-01-01

    Cryo-EM of large, macromolecular assemblies has seen a significant increase in the numbers of high-resolution structures since the arrival of direct electron detectors. However, sub-nanometre resolution cryo-EM structures are rare compared with crystal structure depositions, particularly for relatively small particles (<400 kDa). Here we demonstrate the benefits of Volta phase plates for single-particle analysis by time-efficient cryo-EM structure determination of 257 kDa human peroxiredoxin-3 dodecamers at 4.4 Å resolution. The Volta phase plate improves the applicability of cryo-EM for small molecules and accelerates structure determination.

  14. BVRI Photometric Study of the Short Period Solar Type Near-Contact W UMa Binary, FF Vulpeculae

    NASA Astrophysics Data System (ADS)

    Caton, Daniel B.; Samec, Ronald G.; Nyaude, Ropafadzo; Van Hamme, Walter V.

    2016-01-01

    High precision BVRcIc light curves of FF Vul were observed during the Fall, 2015 season at the Dark Sky Observatory 0.81-m reflector of Appalachian State University, and the SARA North 0.91-m reflector at KPNO. It is an eclipsing binary with a period of only 0.444983 (2) d. This is the shortest period of our recently studied Pre Contact W UMa Binary (PCWB's), V2421 Cyg, V1043 Cas, ZZ Eri, V500 Peg, and Mis V1287. Our Binary Maker fits and our Wilson-Devinney solution show that the binary is a near-contact, semidetached binary, i.e., a V1010 Oph type configuration (the more massive component has filled its critical lobe while the secondary component is under-filling). Five times of minimum light were calculated, 3 primary and 2 secondary eclipses from our present observations:HJD I = 2457285.7262 ±0.0002, 2457306.6425 ±0.0002, 2457310.6469 ±0.0002HJD II = 2457279.7222 ±0.0006, 2457280.6124 ±0.0017.The following quadratic ephemerides was determined from all available times of minimum light:JDHelMinI=2457310.6473±0.0007d + 0.4449758±0.0000002 X E -0.00000000006± 0.00000000001 X E2The continuous 20 year period study reveals a period decrease in the orbital period at about the 6 sigma level. Our modeling shows a near-equatorial hot spot on the following side of the secondary component. This is probably due to a matter transfer onto the secondary component. The light curve has a large difference in primary and secondary amplitudes and the light curve solution gives a component temperature difference of more than 1500 K. The solution shows a total secondary eclipse of 23 minutes duration. As expected in binaries of this type, it has a cool spot region on its primary component.

  15. Covariance Matrix Estimation for the Cryo-EM Heterogeneity Problem*

    PubMed Central

    Katsevich, E.; Katsevich, A.; Singer, A.

    2015-01-01

    In cryo-electron microscopy (cryo-EM), a microscope generates a top view of a sample of randomly oriented copies of a molecule. The problem of single particle reconstruction (SPR) from cryo-EM is to use the resulting set of noisy two-dimensional projection images taken at unknown directions to reconstruct the three-dimensional (3D) structure of the molecule. In some situations, the molecule under examination exhibits structural variability, which poses a fundamental challenge in SPR. The heterogeneity problem is the task of mapping the space of conformational states of a molecule. It has been previously suggested that the leading eigenvectors of the covariance matrix of the 3D molecules can be used to solve the heterogeneity problem. Estimating the covariance matrix is challenging, since only projections of the molecules are observed, but not the molecules themselves. In this paper, we formulate a general problem of covariance estimation from noisy projections of samples. This problem has intimate connections with matrix completion problems and high-dimensional principal component analysis. We propose an estimator and prove its consistency. When there are finitely many heterogeneity classes, the spectrum of the estimated covariance matrix reveals the number of classes. The estimator can be found as the solution to a certain linear system. In the cryo-EM case, the linear operator to be inverted, which we term the projection covariance transform, is an important object in covariance estimation for tomographic problems involving structural variation. Inverting it involves applying a filter akin to the ramp filter in tomography. We design a basis in which this linear operator is sparse and thus can be tractably inverted despite its large size. We demonstrate via numerical experiments on synthetic datasets the robustness of our algorithm to high levels of noise. PMID:25699132

  16. EM-21 Retrieval Knowledge Center: Waste Retrieval Challenges

    SciTech Connect

    Fellinger, Andrew P.; Rinker, Michael W.; Berglin, Eric J.; Minichan, Richard L.; Poirier, Micheal R.; Gauglitz, Phillip A.; Martin, Bruce A.; Hatchell, Brian K.; Saldivar, Eloy; Mullen, O Dennis; Chapman, Noel F.; Wells, Beric E.; Gibbons, Peter W.

    2009-04-10

    EM-21 is the Waste Processing Division of the Office of Engineering and Technology, within the U.S. Department of Energy’s (DOE) Office of Environmental Management (EM). In August of 2008, EM-21 began an initiative to develop a Retrieval Knowledge Center (RKC) to provide the DOE, high level waste retrieval operators, and technology developers with centralized and focused location to share knowledge and expertise that will be used to address retrieval challenges across the DOE complex. The RKC is also designed to facilitate information sharing across the DOE Waste Site Complex through workshops, and a searchable database of waste retrieval technology information. The database may be used to research effective technology approaches for specific retrieval tasks and to take advantage of the lessons learned from previous operations. It is also expected to be effective for remaining current with state-of-the-art of retrieval technologies and ongoing development within the DOE Complex. To encourage collaboration of DOE sites with waste retrieval issues, the RKC team is co-led by the Savannah River National Laboratory (SRNL) and the Pacific Northwest National Laboratory (PNNL). Two RKC workshops were held in the Fall of 2008. The purpose of these workshops was to define top level waste retrieval functional areas, exchange lessons learned, and develop a path forward to support a strategic business plan focused on technology needs for retrieval. The primary participants involved in these workshops included retrieval personnel and laboratory staff that are associated with Hanford and Savannah River Sites since the majority of remaining DOE waste tanks are located at these sites. This report summarizes and documents the results of the initial RKC workshops. Technology challenges identified from these workshops and presented here are expected to be a key component to defining future RKC-directed tasks designed to facilitate tank waste retrieval solutions.

  17. Size-resolved chemistry of aerosols produced by Halema'uma'u eruption 2008-2009, Kilauea Volcano, Hawai'i

    NASA Astrophysics Data System (ADS)

    Ilyinskaya, E.; Martin, R.; Edmonds, M.; Sutton, A. J.; Elias, T.; Werner, C. A.

    2009-12-01

    A dense quiescent plume has been emitted continuously from the 2008 eruptive vent in Halema'uma'u crater since March 2008. Aerosol particles were sampled near-source in the young plume (<30 s old) in May 2008 and April 2009, and at 10 km downwind (April 2009 only). We also sampled the plume from Pu'u O'o vent both near-source and 8-10 km downwind (2007 to 2009). Sampling was performed using filter packs and a cascade impactor that collects and segregates PM10 (particle matter <10 μm) into 14 size fractions. The collected PM was analysed for SO42-, F-, Cl-, Na+, K+, Ca2+ and Mg2+. Our results show a distinctive peak of sulphate abundance at ~0.3-0.5 μm in the 2008 and 2009 summit samples. The total SO42- mass concentration collected in each sampling run correlates well with that of metals but poorly with Cl- and F-. Downwind measurements of PM from Halema'uma'u and Pu'u O'o show SO42- in the same narrow size bin (0.3-0.5 μm) with concentrations similar to, or higher than at source. It is noteworthy that the particles appear not to have grown when the plume has drifted 5-10 km downwind. However, a 1 μm size mode of SO42- seen at Pu'u O'o crater rim (not seen at Halema'uma'u) is absent from the downwind plume. This result leads us to believe that the particles grow rapidly after emission but get scavenged efficiently once they reach a certain size (>0.5 μm). The formation of aerosol measured downwind is dominated by oxidation of SO2 to SO42- in the plume. The ratio of Cl-/SO42- is higher downwind than at the source in both Halema'uma'u and Pu'u O'o plumes, and increases further during rainfall; we propose that the Cl--bearing aerosol is formed by dissolution of HCl gas into water droplets in the plume.

  18. Single-particle cryo-EM at crystallographic resolution

    PubMed Central

    Cheng, Yifan

    2015-01-01

    Until only a few years ago, single-particle electron cryo-microscopy (cryo-EM) was usually not the first choice for many structural biologists due to its limited resolution in the range of nanometer to subnanometer. Now, this method rivals X-ray crystallography in terms of resolution and can be used to determine atomic structures of macromolecules that are either refractory to crystallization or difficult to crystallize in specific functional states. In this review, I discuss the recent breakthroughs in both hardware and software that transformed cryo-microscopy, enabling understanding of complex biomolecules and their functions at atomic level. PMID:25910205

  19. A compulsator driven rapid-fire EM-gun

    SciTech Connect

    Pratap, S.B.; Bird, W.L.

    1984-03-01

    A compulsator-driven railgun is an attractive alternative to the homopolar generator-inductor-switch configuration, especially for repetitive duty. A conceptual design of a rapid-fire EM-gun system is presented. The generator is sized to accelerate a 0.08-kg projectile to 2 to 3 km/s at a 60 pulse-per-second repetition rate. Initial design parameters are discussed, and example current and velocity waveforms are given. The generator is discharged at the proper phase angle to provide a current zero just as the projectile exits the muzzle of the railgun.

  20. EM Modelling of RF Propagation Through Plasma Plumes

    NASA Astrophysics Data System (ADS)

    Pandolfo, L.; Bandinelli, M.; Araque Quijano, J. L.; Vecchi, G.; Pawlak, H.; Marliani, F.

    2012-05-01

    Electric propulsion is a commercially attractive solution for attitude and position control of geostationary satellites. Hall-effect ion thrusters generate a localized plasma flow in the surrounding of the satellite, whose impact on the communication system needs to be qualitatively and quantitatively assessed. An electromagnetic modelling tool has been developed and integrated into the Antenna Design Framework- ElectroMagnetic Satellite (ADF-EMS). The system is able to guide the user from the plume definition phases through plume installation and simulation. A validation activity has been carried out and the system has been applied to the plume modulation analysis of SGEO/Hispasat mission.

  1. 77 FR 4225 - Oral Dosage Form New Animal Drugs; Milbemycin Oxime, Lufenuron, and Praziquantel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-27

    ... various internal parasites in dogs. DATES: This rule is effective January 27, 2012. FOR FURTHER... whipworm, and adult tapeworm infections in dogs and puppies 2 pounds of body weight or greater and 6 weeks.... 510.600(c) of this chapter. (c) (d) Conditions of use--(1) Dogs--(i) Amount. 0.5 mg milbemycin...

  2. 77 FR 47511 - New Animal Drugs; Cephalexin; Fentanyl; Milbemycin Oxime and Praziquantel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-09

    ... CE \\1\\ Meacham Blvd., Ft. Chewable Tablets for treatment of secondary 520.376 Worth, TX 76137. Dogs. superficial bacterial pyoderma in dogs caused by susceptible strains of Staphylococcus pseudintermedius. 141... procedures in Madison, WI 53703. dogs. 141-338 Novartis Animal INTERCEPTOR SPECTRUM Original approval for...

  3. Impact of Annual Praziquantel Treatment on Urogenital Schistosomiasis in a Seasonal Transmission Focus in Central Senegal.

    PubMed

    Senghor, Bruno; Diaw, Omar Talla; Doucoure, Souleymane; Seye, Mouhamadane; Diallo, Adiouma; Talla, Idrissa; Bâ, Cheikh T; Sokhna, Cheikh

    2016-03-01

    In Sub-Saharan Africa, urogenital schistosomiasis remains a significant public health problem, causing 150.000 deaths/year with approximately 112 million cases diagnosed. The Niakhar district is a disease hotspot in central Senegal where transmission occurs seasonally with high prevalences. The aim of this study was to determine the effect of annual treatment over 3 years on the seasonal transmission dynamics of S. haematobium in 9 villages in the Niakhar district. Adults and children aged between 5 and 60 years were surveyed from 2011 to 2014. Urine samples were collected door-to-door and examined for S. haematobium eggs at baseline in June 2011, and all participants were treated in August 2011 with PZQ (40 mg/kg). After this initial examination, evaluations were conducted at 3 successive time points from September 2011 to March 2014, to measure the efficacy of the annual treatments and the rates of reinfection. Each year, during the transmission period, from July to November-December, malacological surveys were also carried out in the fresh water bodies of each village to evaluate the infestation of the snail intermediate hosts. At baseline, the overall prevalence of S. haematobium infection was 57.7%, and the proportion of heavy infection was 45.3%, but one month after the first treatment high cure rates (92.9%) were obtained. The overall infection prevalence and proportion of heavy infection intensities were drastically reduced to 4.2% and 2.3%, respectively. The level of the first reinfection in February-March 2012 was 9.5%. At follow-up time points, prevalence levels varied slightly between reinfection and treatment from 9.5% in June 2012 to 0.3% in March 2013, 11.2 in June 2013, and 10.1% April 2014. At the end of the study, overall prevalence was significantly reduced from 57.7% to 10.1%. The overall rate of infested Bulinid snails was reduced after repeated treatment from 0.8% in 2012 to 0.5% in 2013. Repeated annual treatments are suggested to have a considerable impact on the transmission dynamics of S. haematobium in Niakhar, due to the nature of the epidemiological system with seasonal transmission. Thus, to maintain this benefit and continue to reduce the morbidity of urogenital schistosomiasis, other approaches should be integrated into the strategy plans of the National program to achieve the goal of urogenital schistosomiasis elimination in seasonal foci in Senegal. PMID:27015646

  4. Impact of Annual Praziquantel Treatment on Urogenital Schistosomiasis in a Seasonal Transmission Focus in Central Senegal

    PubMed Central

    Senghor, Bruno; Diaw, Omar Talla; Doucoure, Souleymane; Seye, Mouhamadane; Diallo, Adiouma; Talla, Idrissa; Bâ, Cheikh T.; Sokhna, Cheikh

    2016-01-01

    In Sub-Saharan Africa, urogenital schistosomiasis remains a significant public health problem, causing 150.000 deaths/year with approximately 112 million cases diagnosed. The Niakhar district is a disease hotspot in central Senegal where transmission occurs seasonally with high prevalences. The aim of this study was to determine the effect of annual treatment over 3 years on the seasonal transmission dynamics of S. haematobium in 9 villages in the Niakhar district. Adults and children aged between 5 and 60 years were surveyed from 2011 to 2014. Urine samples were collected door-to-door and examined for S. haematobium eggs at baseline in June 2011, and all participants were treated in August 2011 with PZQ (40 mg/kg). After this initial examination, evaluations were conducted at 3 successive time points from September 2011 to March 2014, to measure the efficacy of the annual treatments and the rates of reinfection. Each year, during the transmission period, from July to November-December, malacological surveys were also carried out in the fresh water bodies of each village to evaluate the infestation of the snail intermediate hosts. At baseline, the overall prevalence of S. haematobium infection was 57.7%, and the proportion of heavy infection was 45.3%, but one month after the first treatment high cure rates (92.9%) were obtained. The overall infection prevalence and proportion of heavy infection intensities were drastically reduced to 4.2% and 2.3%, respectively. The level of the first reinfection in February-March 2012 was 9.5%. At follow-up time points, prevalence levels varied slightly between reinfection and treatment from 9.5% in June 2012 to 0.3% in March 2013, 11.2 in June 2013, and 10.1% April 2014. At the end of the study, overall prevalence was significantly reduced from 57.7% to 10.1%. The overall rate of infested Bulinid snails was reduced after repeated treatment from 0.8% in 2012 to 0.5% in 2013. Repeated annual treatments are suggested to have a considerable impact on the transmission dynamics of S. haematobium in Niakhar, due to the nature of the epidemiological system with seasonal transmission. Thus, to maintain this benefit and continue to reduce the morbidity of urogenital schistosomiasis, other approaches should be integrated into the strategy plans of the National program to achieve the goal of urogenital schistosomiasis elimination in seasonal foci in Senegal. PMID:27015646

  5. 21 CFR 520.1872 - Praziquantel, pyrantel pamoate, and febantel tablets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... tapeworms (Dipylidium caninum, Taenia pisiformis, Echinococcus granulosus); hookworms (Ancylostoma caninum... for the removal and control of tapeworm Echinococcus multilocularis in dogs. (iii) Limitations. Do...

  6. 21 CFR 520.1872 - Praziquantel, pyrantel pamoate, and febantel tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... tapeworms (Dipylidium caninum, Taenia pisiformis, Echinococcus granulosus); hookworms (Ancylostoma caninum... for the removal and control of tapeworm Echinococcus multilocularis in dogs. (iii) Limitations. Do...

  7. 21 CFR 520.1872 - Praziquantel, pyrantel pamoate, and febantel tablets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... tapeworms (Dipylidium caninum, Taenia pisiformis, Echinococcus granulosus); hookworms (Ancylostoma caninum... for the removal and control of tapeworm Echinococcus multilocularis in dogs. (iii) Limitations. Do...

  8. 21 CFR 520.1872 - Praziquantel, pyrantel pamoate, and febantel tablets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... tapeworms (Dipylidium caninum, Taenia pisiformis, Echinococcus granulosus); hookworms (Ancylostoma caninum... for the removal and control of tapeworm Echinococcus multilocularis in dogs. (iii) Limitations. Do...

  9. 21 CFR 520.1872 - Praziquantel, pyrantel pamoate, and febantel tablets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... tapeworms (Dipylidium caninum, Taenia pisiformis, Echinococcus granulosus); hookworms (Ancylostoma caninum... for the removal and control of tapeworm Echinococcus multilocularis in dogs. (iii) Limitations. Do...

  10. Developing State and National Evaluation Infrastructures- Guidance for the Challenges and Opportunities of EM&V

    SciTech Connect

    Schiller, Steven R.; Goldman, Charles A.

    2011-06-24

    Evaluating the impacts and effectiveness of energy efficiency programs is likely to become increasingly important for state policymakers and program administrators given legislative mandates and regulatory goals and increasing reliance on energy efficiency as a resource. In this paper, we summarize three activities that the authors have conducted that highlight the expanded role of evaluation, measurement and verification (EM&V): a study that identified and analyzed challenges in improving and scaling up EM&V activities; a scoping study that identified issues involved in developing a national efficiency EM&V standard; and lessons learned from providing technical assistance on EM&V issues to states that are ramping up energy efficiency programs. The lessons learned are summarized in 13 EM&V issues that policy makers should address in each jurisdiction and which are listed and briefly described. The paper also discusses how improving the effectiveness and reliability of EM&V will require additional capacity building, better access to existing EM&V resources, new methods to address emerging issues and technologies, and perhaps foundational documents and approaches to improving the credibility and cross jurisdictional comparability of efficiency investments. Two of the potential foundational documents discussed are a national EM&V standard or resource guide and regional deemed savings and algorithm databases.

  11. EMS Instructor Training Program. National Standard Curriculum. Instructor Guide. Student Guide.

    ERIC Educational Resources Information Center

    National Highway Traffic Safety Administration (DOT), Washington, DC.

    This guide for teaching a course to prepare emergency medical service (EMS) trainers focuses on the skills necessary to present any of the Department of Transportation (DOT), National Highway Traffic Safety Administration (NHTSA) EMS courses. Course topics are as follows: (1) introduction; (2) instructor roles and responsibilities; (3) legal…

  12. Method for evaluating compatibility of commercial electromagnetic (EM) microsensor tracking systems with surgical and imaging tables

    NASA Astrophysics Data System (ADS)

    Nafis, Christopher; Jensen, Vern; von Jako, Ron

    2008-03-01

    Electromagnetic (EM) tracking systems have been successfully used for Surgical Navigation in ENT, cranial, and spine applications for several years. Catheter sized micro EM sensors have also been used in tightly controlled cardiac mapping and pulmonary applications. EM systems have the benefit over optical navigation systems of not requiring a line-of-sight between devices. Ferrous metals or conductive materials that are transient within the EM working volume may impact tracking performance. Effective methods for detecting and reporting EM field distortions are generally well known. Distortion compensation can be achieved for objects that have a static spatial relationship to a tracking sensor. New commercially available micro EM tracking systems offer opportunities for expanded image-guided navigation procedures. It is important to know and understand how well these systems perform with different surgical tables and ancillary equipment. By their design and intended use, micro EM sensors will be located at the distal tip of tracked devices and therefore be in closer proximity to the tables. Our goal was to define a simple and portable process that could be used to estimate the EM tracker accuracy, and to vet a large number of popular general surgery and imaging tables that are used in the United States and abroad.

  13. Covariance Structure Model Fit Testing under Missing Data: An Application of the Supplemented EM Algorithm

    ERIC Educational Resources Information Center

    Cai, Li; Lee, Taehun

    2009-01-01

    We apply the Supplemented EM algorithm (Meng & Rubin, 1991) to address a chronic problem with the "two-stage" fitting of covariance structure models in the presence of ignorable missing data: the lack of an asymptotically chi-square distributed goodness-of-fit statistic. We show that the Supplemented EM algorithm provides a convenient…

  14. The Relationship between the Bock-Aitkin Procedure and the EM Algorithm for IRT Model Estimation.

    ERIC Educational Resources Information Center

    Hsu, Yaowen; Ackerman, Terry A.; Fan, Meichu

    It has previously been shown that the Bock-Aitkin procedure (R. Bock and M. Aitkin, 1981) is an instance of the EM algorithm when trying to find the marginal maximum likelihood estimate for a discrete latent ability variable (latent trait). In this paper, it is shown that the Bock-Aitkin procedure is a numerical implementation of the EM algorithm…

  15. Global Convergence of the EM Algorithm for Unconstrained Latent Variable Models with Categorical Indicators

    ERIC Educational Resources Information Center

    Weissman, Alexander

    2013-01-01

    Convergence of the expectation-maximization (EM) algorithm to a global optimum of the marginal log likelihood function for unconstrained latent variable models with categorical indicators is presented. The sufficient conditions under which global convergence of the EM algorithm is attainable are provided in an information-theoretic context by…

  16. Signaling of cell fate determination by the TPD1 small protein and EMS1 receptor kinase

    PubMed Central

    Jia, Gengxiang; Liu, Xiaodong; Owen, Heather A.; Zhao, Dazhong

    2008-01-01

    Sexual reproduction requires the specification of cells with distinct fates in plants and animals. The EMS1 (also known as EXS) leucine-rich repeat receptor-like kinase (LRR-RLK) and TPD1 small protein play key roles in regulating somatic and reproductive cell fate determination in Arabidopsis anthers. Here, we show that ectopic expression of TPD1 causes abnormal differentiation of somatic and reproductive cells in anthers. In addition, ectopic TPD1 activity requires functional EMS1. Yeast two-hybrid, pull-down, and coimmunoprecipitation analyses further demonstrate that TPD1 interacts with EMS1 in vitro and in vivo. Moreover, TPD1 induces EMS1 phosphorylation in planta. Thus, our results suggest that TPD1 serves as a ligand for the EMS1 receptor kinase to signal cell fate determination during plant sexual reproduction. PMID:18250314

  17. A Generalized Fast Frequency Sweep Algorithm for Coupled Circuit-EM Simulations

    SciTech Connect

    Rockway, J D; Champagne, N J; Sharpe, R M; Fasenfest, B

    2004-01-14

    Frequency domain techniques are popular for analyzing electromagnetics (EM) and coupled circuit-EM problems. These techniques, such as the method of moments (MoM) and the finite element method (FEM), are used to determine the response of the EM portion of the problem at a single frequency. Since only one frequency is solved at a time, it may take a long time to calculate the parameters for wideband devices. In this paper, a fast frequency sweep based on the Asymptotic Wave Expansion (AWE) method is developed and applied to generalized mixed circuit-EM problems. The AWE method, which was originally developed for lumped-load circuit simulations, has recently been shown to be effective at quasi-static and low frequency full-wave simulations. Here it is applied to a full-wave MoM solver, capable of solving for metals, dielectrics, and coupled circuit-EM problems.

  18. AVALIAÇÃO DA PRESENÇA DE ENDOSSIMBIONTES Cardinium em DIFERENTES ESPÉCIES DE ARTRÓPODES.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A presença de endossimbiontes do gênero Cardinium em alguns grupos de artrópodes foi recentemente relatada e relacionada com diversas alterações reprodutivas em seus hospedeiros, tais como feminilização de ácaros, partenogênese em parasitóides, incompatibilidade citoplasmática e aumento da fecundida...

  19. Aristarchus's <em>On the Sizes and Distances of the Sun and the Moonem>: Greek and Arabic Texts

    NASA Astrophysics Data System (ADS)

    Berggren, J. L.; Sidoli, N.

    2007-05-01

    In the 1920s, T. L. Heath pointed out that historians of mathematics have "given too little attention to Aristarchus". This is still true today. The Greek text of Aristarchus's On the Sizes and Distances of the Sun and the Moonem> has received little attention; the Arabic editions virtually none. Much of what this text has to tell us about ancient and medieval mathematics and the mathematical sciences has gone unnoticed. It should be taken as an important source for our understanding of the mathematical sciences of the early Hellenistic period.

  20. The EM fields in the Solid Generated by a Fault in a Porous Region

    NASA Astrophysics Data System (ADS)

    Ren, H.; Huang, Q.; Chen, X.

    2015-12-01

    Electrokinetic effect, as one of the most possible generation mechanisms of the seismo-electromagnetic phenomenons associated with natural earthquakes, has interested many researchers. Besides, it is also considered as a potential tool for the water/oil exploration. Recently, we numerically investigated the electromagnetic (EM) fields due to the electrokinetic effect in mixed layered model. The mixed model comprises not only porous layers but also solid layers. We firstly tested a two-layer mixed model. The numerical results show that, in addition to the radiation EM fields, another kind of evanescent EM fields can be generated by the seismic waves arriving at the interface with incident angles greater the critical angle. The evanescent EM fields decay faster than the radiation EM fields when getting away from the interface. For the seismic frequency band, the evanescent EM fields in the solid are still measurable at a distance of, e.g., 2km to the interface. We then tested a eight-layer mixed model. The top and bottom layers are solid and the other layers are porous. A finite fault of 20x10km is located in the porous region. The focal depth is 8km. The applied source time function is a ramp fuction with an arise time of 0.8s. Point stacking method was used to compute the wave-fields caused by the finite fault. Our nuemrical results show that, this model can generate the EM fields before the arrival of seismic waves as well as the residual EM fields. Both the two kinds of EM fields have been observed in field observations. There is a possibility that the anomalous EM activities before big earthquakes may be caused by the fluid flow in the shallow Earth as a result of the stress changes.

  1. Review of selected oceanic EM/EO scattering problems

    NASA Astrophysics Data System (ADS)

    Haller, Merrick C.

    2010-02-01

    Electromagnetic and electro-optical (EM/EO) propagation and scattering in the ocean is of interest for a wide range of science problems. For example, the biological productivity of ocean waters through photochemical processes is governed by the vertical attenuation of solar radiation. Also, EO scattering theory is the primary basis for determining biogeochemical parameters (e.g. phytoplankton, suspended sediments, and dissolved matter) from the water leaving optical radiance. In addition, EO scattering from suspended sediments and bubbles is the limiting factor for active lidar systems used to map the sea bottom. This work will review specific applications of EO/EM scattering theory with regard to the influence of bubbles and droplets on remote sensing in the nearshore ocean. The current state of understanding concerning models and applications for optical scattering from bubbles in the water column as well as microwave scattering from water droplets produced by breaking waves at the ocean surface will be discussed as well as future research directions.

  2. The Search for Gravitational Wave EM Counterparts with Swift

    NASA Astrophysics Data System (ADS)

    Kennea, Jamie; Evans, Phil; Swift GW follow-up Team

    2016-04-01

    We present the plan to search for electromagnetic counterparts of Gravitational Waves (GWs) discovered during the current and upcoming runs of the LIGO and Virgo detectors. As we enter a period where the sensitivity of the current generation of GW detectors approaches a high probability of the first detection of a real GW signal, confirmation of the reality of these triggers will be greatly improved if an EM counterpart can be found. Swift’s ability to rapidly respond to high priority target-of-opportunity observations, it’s multi-wavelength capabilities and low overhead observing make it a seemingly ideal follow-up facility. However comparing the size of the expected GW error regions with the fields of view of the Swift XRT and UVOT telescopes, we find that covering the large GW error regions would require a unreasonably large number of pointings. We present our method of meeting this challenge, by both reducing the problem using Galaxy targeting, and by operating Swift in an entirely new way in order to cover the still large number of fields needed to chase down the EM counterpart before it disappears.

  3. Chapter 19: HVAC Controls (DDC/EMS/BAS) Evaluation Protocol

    SciTech Connect

    Romberger, J.

    2014-11-01

    The HVAC Controls Evaluation Protocol is designed to address evaluation issues for direct digital controls/energy management systems/building automation systems (DDC/EMS/BAS) that are installed to control heating, ventilation, and air-conditioning (HVAC) equipment in commercial and institutional buildings. (This chapter refers to the DDC/EMS/BAS measure as HVAC controls.) This protocol may also be applicable to industrial facilities such as clean rooms and labs, which have either significant HVAC equipment or spaces requiring special environmental conditions. This protocol addresses only HVAC-related equipment and the energy savings estimation methods associated with installing such control systems as an energy efficiency measure. The affected equipment includes: Air-side equipment (air handlers, direct expansion systems, furnaces, other heating- and cooling-related devices, terminal air distribution equipment, and fans); Central plant equipment (chillers, cooling towers, boilers, and pumps). These controls may also operate or affect other end uses, such as lighting, domestic hot water, irrigation systems, and life safety systems such as fire alarms and other security systems. Considerable nonenergy benefits, such as maintenance scheduling, system component troubleshooting, equipment failure alarms, and increased equipment lifetime, may also be associated with these systems. When connected to building utility meters, these systems can also be valuable demand-limiting control tools. However, this protocol does not evaluate any of these additional capabilities and benefits.

  4. Contactless ultrasonic treatment of melts using EM induction

    NASA Astrophysics Data System (ADS)

    Bojarevics, V.; Djambazov, G.; Lebon, G. S. B.; Pericleous, K. A.

    2015-06-01

    Ultrasound Treatment (UT) is commonly used in light alloys during solidification to refine microstructure, or disperse immersed particles. A sonotrode probe introduced into the melt generates sound waves that are strong enough to produce cavitation of dissolved gases. The same method cannot be used in high temperature melts, or for highly reactive alloys, due to probe erosion and melt contamination. An alternative, contactless method of generating sound waves is proposed and investigated theoretically in this paper, using electromagnetic (EM) induction. In addition to strong vibration, the EM induction currents generate strong stirring in the melt that aids distribution of the UT effect to large volumes of material. In a typical application, the same induction coil surrounding the crucible used to melt the alloy may be adopted for UT with suitable frequency tuning. Alternatively - or in addition - a top coil may be used. For industrial use, instead of multiple sonotrodes as has been the practice in scaling up, modelling shows that one simply has to alter the coil geometry and current to suit. To reach sinusoidal pressure fluctuations suitable for cavitation it may be necessary to tune the induction coil frequency for resonance, given the crucible dimensions.

  5. The Spot Variability and Related Brightness variations of the Solar Type PreContact W UMa Binary System V1001 Cas

    NASA Astrophysics Data System (ADS)

    Samec, Ronald George; Koenke, Sam S.; Faulkner, Danny R.

    2015-08-01

    A new classification of eclipsing binary has emerged, Pre Contact WUMa Binaries (PCWB’s, Samec et al. 2012). These solar-type systems are usually detached or semidetached with one or both components under filling their critical Roche lobes. They usually have EA or EB-type light curves (unequal eclipse depths, indicating components with substantially different temperatures). The accepted scenario for these W UMa binaries is that they are undergoing steady but slow angular momentum losses due to magnetic braking as stellar winds blow radially away on stiff bipolar field lines. These binaries are believed to come into stable contact and eventually coalesce into blue straggler type, single, fast rotating A-type stars (Guinan and Bradstreet,1988). High precision 2012 and 2009 light curves are compared for the very short period (~0.43d) Precontact W UMa Binary (PCWB), V1001 Cassiopeia. This is the shortest period PCWB found so far. Its short period, similar to the majority of W UMa’s, in contrast to its distinct Algol-type light curve, make it a very rare and interesting system. Our solutions of light curves separated by some three years give approximately the same physical parameters. However the spots radically change, in temperature, area and position causing a distinctive variation in the shape of the light curves. We conclude that spots are very active on this solar type dwarf system and that it may mimic its larger cousins, the RS CVn binaries.

  6. The EM SSAB Annual Work Plan Process: Focusing Board Efforts and Resources - 13667

    SciTech Connect

    Young, Ralph

    2013-07-01

    One of the most daunting tasks for any new member of a local board of the Environmental Management Site Specific Advisory Board (EM SSAB) is to try to understand the scope of the clean-up activities going on at the site. In most cases, there are at least two or three major cleanup activities in progress as well as monitoring of past projects. When planning for future projects is added to the mix, the list of projects can be long. With the clean-up activities involving all major environmental media - air, water, soils, and groundwater, new EM SSAB members can find themselves totally overwhelmed and ineffective. Helping new members get over this initial hurdle is a major objective of EM and all local boards of the EM SSAB. Even as members start to understand the size and scope of the projects at a site, they can still be frustrated at the length of time it takes to see results and get projects completed. Many project and clean-up timelines for most of the sites go beyond 10 years, so it's not unusual for an EM SSAB member to see the completion of only 1 or 2 projects over the course of their 6-year term on the board. This paper explores the annual work planning process of the EM SSAB local boards, one tool that can be used to educate EM SSAB members into seeing the broader picture for the site. EM SSAB local work plans divide the site into projects focused on a specific environmental issue or media such as groundwater and/or waste disposal options. Projects are further broken down into smaller segments by highlighting major milestones. Using these metrics, local boards of the EM SSAB can start to quantify the effectiveness of the project in achieving the ultimate goal of site clean-up. These metrics can also trigger board advice and recommendations for EM. At the beginning of each fiscal year, the EM SSAB work plan provides a road map with quantifiable checkpoints for activities throughout the year. When the work plans are integrated with site-specific, enforceable

  7. Linear array implementation of the EM algorithm for PET image reconstruction

    SciTech Connect

    Rajan, K.; Patnaik, L.M.; Ramakrishna, J.

    1995-08-01

    The PET image reconstruction based on the EM algorithm has several attractive advantages over the conventional convolution back projection algorithms. However, the PET image reconstruction based on the EM algorithm is computationally burdensome for today`s single processor systems. In addition, a large memory is required for the storage of the image, projection data, and the probability matrix. Since the computations are easily divided into tasks executable in parallel, multiprocessor configurations are the ideal choice for fast execution of the EM algorithms. In tis study, the authors attempt to overcome these two problems by parallelizing the EM algorithm on a multiprocessor systems. The parallel EM algorithm on a linear array topology using the commercially available fast floating point digital signal processor (DSP) chips as the processing elements (PE`s) has been implemented. The performance of the EM algorithm on a 386/387 machine, IBM 6000 RISC workstation, and on the linear array system is discussed and compared. The results show that the computational speed performance of a linear array using 8 DSP chips as PE`s executing the EM image reconstruction algorithm is about 15.5 times better than that of the IBM 6000 RISC workstation. The novelty of the scheme is its simplicity. The linear array topology is expandable with a larger number of PE`s. The architecture is not dependant on the DSP chip chosen, and the substitution of the latest DSP chip is straightforward and could yield better speed performance.

  8. The Understanding of Astronomy Concepts by Students from Basic Education of a Public School. (Spanish Title: El Entendimiento de Conceptos de Aastronmía Por Los Alumnos de Educación Básica en Una Escuela Pública.) O Entendimento de Conceitos de Astronomia Por Alunos da Educação Básica: O Caso de Uma Escola Pública Brasileira

    NASA Astrophysics Data System (ADS)

    Iria Machado, Daniel; dos Santos, Carlos

    2011-07-01

    movimiento de la Luna, el movimiento aparente del Sol sobre la esfera celeste, los eclipses, las dimensiones y las distancias en el Universo, el brillo de las estrellas y su observación de la Tierra. Si bien ha habido un pequeño progreso en la proporción de respuestas aceptables científicamente cuando se cotejó el octavo grado de la enseñanza primaria con el quinto, y el último año de la enseñanza secundaria con el primero, se observó un predominio de las concepciones alternativas en relación a la mayoría de los temas explorados, que continuó hasta los últimos años de la educación básica. Una comparación con los datos encontrados en investigaciones realizadas en otros contextos socioculturales revelaron, en muchos aspectos, conceptos y dificultades similares expresadas por los estudiantes. Apresentam-se os resultados de uma investigação sobre a compreensão de conceitos astronômicos básicos, da qual participaram 561 estudantes da quinta série do Ensino Fundamental ao terceiro ano do Ensino Médio de uma escola pública da cidade de Foz do Iguaçu. Um teste com 20 questões de múltipla escolha foi aplicado para identificar as concepções mais comuns expressadas pelos alunos. Esse instrumento de coleta de dados foi elaborado com base na literatura sobre concepções alternativas e abordou os seguintes temas: o ciclo dia-noite; os fusos horários; as estações do ano; as fases da Lua; o movimento da Lua; o movimento aparente do Sol na esfera celeste; os eclipses; as dimensões e distâncias no Universo; o brilho das estrelas e sua observação da Terra. Embora se tenha verificado um pequeno progresso na proporção de respostas cientificamente aceitáveis ao se cotejar a oitava série do Ensino Fundamental com a quinta, e a terceira série do Ensino Médio com a primeira, houve o predomínio de concepções alternativas em relação à maior parte dos temas explorados, as quais persistiram até o último ano da Educação Básica. A comparação com

  9. The Understanding of Astronomy Concepts by Students from Basic Education of a Public School. (Spanish Title: El Entendimiento de Conceptos de Aastronmía Por Los Alumnos de Educación Básica en Una Escuela Pública.) O Entendimento de Conceitos de Astronomia Por Alunos da Educação Básica: O Caso de Uma Escola Pública Brasileira

    NASA Astrophysics Data System (ADS)

    Iria Machado, Daniel; dos Santos, Carlos

    2011-07-01

    movimiento de la Luna, el movimiento aparente del Sol sobre la esfera celeste, los eclipses, las dimensiones y las distancias en el Universo, el brillo de las estrellas y su observación de la Tierra. Si bien ha habido un pequeño progreso en la proporción de respuestas aceptables científicamente cuando se cotejó el octavo grado de la enseñanza primaria con el quinto, y el último año de la enseñanza secundaria con el primero, se observó un predominio de las concepciones alternativas en relación a la mayoría de los temas explorados, que continuó hasta los últimos años de la educación básica. Una comparación con los datos encontrados en investigaciones realizadas en otros contextos socioculturales revelaron, en muchos aspectos, conceptos y dificultades similares expresadas por los estudiantes. Apresentam-se os resultados de uma investigação sobre a compreensão de conceitos astronômicos básicos, da qual participaram 561 estudantes da quinta série do Ensino Fundamental ao terceiro ano do Ensino Médio de uma escola pública da cidade de Foz do Iguaçu. Um teste com 20 questões de múltipla escolha foi aplicado para identificar as concepções mais comuns expressadas pelos alunos. Esse instrumento de coleta de dados foi elaborado com base na literatura sobre concepções alternativas e abordou os seguintes temas: o ciclo dia-noite; os fusos horários; as estações do ano; as fases da Lua; o movimento da Lua; o movimento aparente do Sol na esfera celeste; os eclipses; as dimensões e distâncias no Universo; o brilho das estrelas e sua observação da Terra. Embora se tenha verificado um pequeno progresso na proporção de respostas cientificamente aceitáveis ao se cotejar a oitava série do Ensino Fundamental com a quinta, e a terceira série do Ensino Médio com a primeira, houve o predomínio de concepções alternativas em relação à maior parte dos temas explorados, as quais persistiram até o último ano da Educação Básica. A comparação com

  10. A new method for vitrifying samples for cryoEM.

    PubMed

    Razinkov, Ivan; Dandey, Venkata P; Wei, Hui; Zhang, Zhening; Melnekoff, David; Rice, William J; Wigge, Christoph; Potter, Clinton S; Carragher, Bridget

    2016-08-01

    Almost every aspect of cryo electron microscopy (cryoEM) has been automated over the last few decades. One of the challenges that remains to be addressed is the robust and reliable preparation of vitrified specimens of suitable ice thickness. We present results from a new device for preparing vitrified samples. The successful use of the device is coupled to a new "self-blotting" grid that we have developed to provide a method for spreading a sample to a thin film without the use of externally applied filter paper. This new approach has the advantage of using small amounts of protein material, resulting in large areas of ice of a well defined thickness containing evenly distributed single particles. We believe that these methods will in the future result in a system for vitrifying grids that is completely automated. PMID:27288865

  11. Speech articulator measurements using low power EM-wave sensors

    SciTech Connect

    Holzrichter, J.F.; Burnett, G.C.; Ng, L.C.; Lea, W.A.

    1998-01-01

    Very low power electromagnetic (EM) wave sensors are being used to measure speech articulator motions as speech is produced. Glottal tissue oscillations, jaw, tongue, soft palate, and other organs have been measured. Previously, microwave imaging (e.g., using radar sensors) appears not to have been considered for such monitoring. Glottal tissue movements detected by radar sensors correlate well with those obtained by established laboratory techniques, and have been used to estimate a voiced excitation function for speech processing applications. The noninvasive access, coupled with the small size, low power, and high resolution of these new sensors, permit promising research and development applications in speech production, communication disorders, speech recognition and related topics. {copyright} {ital 1998 Acoustical Society of America.}

  12. EM Properties of Magnetic Minerals at RADAR Frequencies

    NASA Technical Reports Server (NTRS)

    Stillman, D. E.; Olhoeft, G. R.

    2005-01-01

    Previous missions to Mars have revealed that Mars surface is magnetic at DC frequency. Does this highly magnetic surface layer attenuate RADAR energy as it does in certain locations on Earth? It has been suggested that the active magnetic mineral on Mars is titanomaghemite and/or titanomagnetite. When titanium is incorporated into a maghemite or magnetite crystal, the Curie temperature can be significantly reduced. Mars has a wide range of daily temperature fluctuations (303K - 143K), which could allow for daily passes through the Curie temperature. Hence, the global dust layer on Mars could experience widely varying magnetic properties as a function of temperature, more specifically being ferromagnetic at night and paramagnetic during the day. Measurements of EM properties of magnetic minerals were made versus frequency and temperature (300K- 180K). Magnetic minerals and Martian analog samples were gathered from a number of different locations on Earth.

  13. Balloting motion of SLEKE launch packages in EM railguns

    NASA Astrophysics Data System (ADS)

    Chu, Szu H.

    1993-01-01

    This paper reports some balloting motion computational results of the SLEKE (Sabot Launched Electric-gun Kinetic Energy) launch packages, which are in their early stage of development. The computation model considers the effects of the EM (Lorentz) propulsion force, friction, air resistance, gravity, elastic forces, and clearance between the launch package and the barrel. The axial, normal and yaw displacement, velocity and acceleration; friction; deformations and forces at the interfacing points are computed. The results of this study indicate that the balloting force for SLEKE launch packages is on the order of the air drag force and that a uniformly distributed power source would be more desirable than sharp pulse current for electromagnetic railguns.

  14. Detection of karst structures using airborne EM and VLF

    SciTech Connect

    Beard, L.P. Nyquist, J.E.; Carpenter, P.J.

    1994-12-31

    Through the combined use of multi-frequency helicopter electromagnetic and VLF data, it is possible to detect and delineate a wide variety of karst structures and possibly to assess their interconnectedness. Multi-frequency EM Can detect karst features if some element of the structure is conductive. This conductive aspect may derive from thick, moist soils in the depression commonly associated with a doline, from conductive fluids in the cavity, or from conductive sediments in the cavity if these occupy a significant portion of it. Multiple loop configurations may also increase the likelihood of detecting karst features. Preliminary evidence indicates total field VLF measurements may be able to detect interconnected karst pathways, so long as the pathways are water or sediment filled. Neither technique can effectively detect dry, resistive air-filled cavities.

  15. Integrated EM & Thermal Simulations with Upgraded VORPAL Software

    SciTech Connect

    D.N. Smithe, D. Karipides, P. Stoltz, G. Cheng, H. Wang

    2011-03-01

    Nuclear physics accelerators are powered by microwaves which must travel in waveguides between room-temperature sources and the cryogenic accelerator structures. The ohmic heat load from the microwaves is affected by the temperature-dependent surface resistance and in turn affects the cryogenic thermal conduction problem. Integrated EM & thermal analysis of this difficult non-linear problem is now possible with the VORPAL finite-difference time-domain simulation tool. We highlight thermal benchmarking work with a complex HOM feed-through geometry, done in collaboration with researchers at the Thomas Jefferson National Accelerator Laboratory, and discuss upcoming design studies with this emerging tool. This work is part of an effort to generalize the VORPAL framework to include generalized PDE capabilities, for wider multi-physics capabilities in the accelerator, vacuum electronics, plasma processing and fusion R&D fields, and we will also discuss user interface and algorithmic upgrades which facilitate this emerging multiphysics capability.

  16. Selling management on the cost benefits of EMS programs

    SciTech Connect

    Beck, W.B.

    1999-07-01

    One of the persistent misconceptions by management is that environmental programs are always a cost to the business. Management tolerates this situation because they recognize the legal and other ethical considerations related to environmental programs, however, they still regard them as a cost and a necessary evil. This paper will present several ideas that can be put into practice by the environmental professionals to counter this management perception. These include the identification and use of macro scale and micro scale cost considerations in the environmental balance sheet to provide management with a different and perhaps more realistic view of the worth of the program. This cost accounting approach should be viewed as just one of the several systems that should make up the modern day environmental management systems (EMS) program.

  17. Making connections. Voice and data solutions for EMS.

    PubMed

    Careless, James; Erich, John

    2008-08-01

    Communications used to be so simple-1) grab the radio, 2) push and talk. Now we're besieged by a confusing assortment of technology and terms-wideband, broadband, VoIP, RoIP, ect.- and a constand thrumming imperative to achieve and improve and perfect some mystical state of full interoperability. Frankly, it can all be a bit much. With this supplement, we hope to clarify you options. We examine the importance of broadband for EMS, with its potential for larger data "pipes" between the hospital and the field; advances in the promising technologies of Voice over IP and Radio over IP; and how some systems are improving their interconnectedness and resulting operations. The jargon can be overwhelming, but the ideas are worth understanding. PMID:18814746

  18. EM modeling of RF drive in DTL tank 4

    SciTech Connect

    Kurennoy, Sergey S.

    2012-06-19

    A 3-D MicroWave Studio model for the RF drive in the LANSCE DTL tank 4 has been built. Both eigensolver and time-domain modeling are used to evaluate maximal fields in the drive module and RF coupling. The LANSCE DTL tank 4 has recently been experiencing RF problems, which may or may not be related to its replaced RF coupler. This situation stimulated a request by Dan Rees to provide EM modeling of the RF drive in the DTL tank 4 (T4). Jim O'Hara provided a CAD model that was imported into the CST Microwave Studio (MWS) and after some modifications became a part of a simplified MWS model of the T4 RF drive. This technical note describes the model and presents simulation results.

  19. TrakEM2 Software for Neural Circuit Reconstruction

    PubMed Central

    Cardona, Albert; Saalfeld, Stephan; Schindelin, Johannes; Arganda-Carreras, Ignacio; Preibisch, Stephan; Longair, Mark; Tomancak, Pavel; Hartenstein, Volker; Douglas, Rodney J.

    2012-01-01

    A key challenge in neuroscience is the expeditious reconstruction of neuronal circuits. For model systems such as Drosophila and C. elegans, the limiting step is no longer the acquisition of imagery but the extraction of the circuit from images. For this purpose, we designed a software application, TrakEM2, that addresses the systematic reconstruction of neuronal circuits from large electron microscopical and optical image volumes. We address the challenges of image volume composition from individual, deformed images; of the reconstruction of neuronal arbors and annotation of synapses with fast manual and semi-automatic methods; and the management of large collections of both images and annotations. The output is a neural circuit of 3d arbors and synapses, encoded in NeuroML and other formats, ready for analysis. PMID:22723842

  20. TrakEM2 software for neural circuit reconstruction.

    PubMed

    Cardona, Albert; Saalfeld, Stephan; Schindelin, Johannes; Arganda-Carreras, Ignacio; Preibisch, Stephan; Longair, Mark; Tomancak, Pavel; Hartenstein, Volker; Douglas, Rodney J

    2012-01-01

    A key challenge in neuroscience is the expeditious reconstruction of neuronal circuits. For model systems such as Drosophila and C. elegans, the limiting step is no longer the acquisition of imagery but the extraction of the circuit from images. For this purpose, we designed a software application, TrakEM2, that addresses the systematic reconstruction of neuronal circuits from large electron microscopical and optical image volumes. We address the challenges of image volume composition from individual, deformed images; of the reconstruction of neuronal arbors and annotation of synapses with fast manual and semi-automatic methods; and the management of large collections of both images and annotations. The output is a neural circuit of 3d arbors and synapses, encoded in NeuroML and other formats, ready for analysis. PMID:22723842

  1. Kaisen. EMS as theater of the streets. Part two.

    PubMed

    Dernocoeur, K; Taigman, M

    1991-03-01

    Passing an EMT or paramedic course is a considerable achievement, as you have had to acquire a huge and fascinating volume of medical knowledge. But, did the program teach you acting skills? Acting? Whoever said that EMS professionals need to know anything about acting? We submit that you do; prehospital workers can gain many unanticipated benefits by using various acting skills and tactics in the field. One such benefit is the avoidance of the "complacency trap," or the boredom that can develop if you adopt the viewpoint that one crisis is much like another. But, more importantly, you will be more effective at delivering prehospital care, and you'll have a lot more fun on the job. PMID:10110186

  2. Suspended-Patch Antenna With Inverted, EM-Coupled Feed

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.

    2004-01-01

    An improved suspended-patch antenna has been designed to operate at a frequency of about 23 GHz with linear polarization and to be one of four identical antennas in a rectangular array. The antenna includes a parasitic patch on top of a suspended dielectric superstrate, an active patch on top of a suspended dielectric substrate, a microstrip on the bottom of the dielectric substrate, and a ground plane. The microstrip, the ground plane, the airgap between them, and the dielectric substrate together constitute a transmission line that has an impedance of 50 Ohm and is electromagnetically (EM) coupled to the active patch. The parasitic patch is, in turn, excited by the active patch. The microstrip feed is characterized as inverted because the microstrip is on the bottom of the substrate, whereas microstrips are usually placed on the tops of dielectric substrates

  3. User's guide for the PWR LOCA analysis capability of the WRAP-EM system

    SciTech Connect

    Beranek, F; Gregory, M V

    1980-02-01

    The Water Reactor Analysis Package (WRAP) has been expanded to provide the capability to analyze loss-of-coolant accidents (LOCAs) in both pressurized water reactors (PWRs) and boiling water reactors (BWRs) by using evaluation models (EMs). The input specifications for modules in the WRAP-EM system are presented in this document along with the JOSHUA input templates. This document, along with the WRAP user's guide, provides a step-by-step procedure for setting up a PWR data base for the WRAP-EM system. 12 refs.

  4. Time-Lapse inversion of EM Tomography data for polymer-injected hydrocarbon reservoirs

    NASA Astrophysics Data System (ADS)

    Cheon, Seiwook; Park, Chanho; Nam, Myung Jin; Son, Jeong-Sul

    2015-04-01

    Polymer flooding is a method to increase the production of hydrocarbon reservoir by injecting polymer solution into the reservoir. For a study on the monitoring fluid variation within the reservoir, we first make analysis on seismic- and electromagnetic (EM)- tomography responses for seismic and electrical-resistivity rock physics models (RPMs) of the reservoir considering polymer fluid. Constructing RPMs are dependent on not only geologic characteristics of reservoir but also reservoir parameters such as fluid-type, fluid saturation, pressure and temperature. When making RPM for monitoring analysis, we assume the geology does not changes while reservoir parameters change to affect responses of seismic and EM tomography data. Specifically when constructing electrical-resistivity RPM, we consider three different types of hydrocarbon reservoirs, which are clean sand, shaly sand, sand-shale lamination, while considering two different types of waters (fresh water and salt water) to make 2wt% polymer solution. To compute time lapse EM and seismic tomography responses for corresponding RPMs of polymer-injected reservoirs, we used 2.5D finite element EM modeling algorithm and staggered-grid finite difference elastic modeling algorithm, respectively. Comparison between sensitivities of seismic and EM tomography to polymer injection confirms that EM tomography is more sensitivity to the polymer injection. For the evaluation of the potential of EM tomography to monitor polymer flooding, this study subsequently develops an efficient time-lapse EM tomography inversion algorithm based on the 2.5D EM tomography modeling. Using the inversion algorithm, we inverted the time-lapse EM tomography data to construct true resistivity models of polymer-injected reservoirs and analyze differences between them. From the time-lapse inversion results, we can observe the differences in time lapse responses between using fresh water and salt water have been decreased in the inverted time

  5. Integration of artificial intelligence applications in the EMS: Issues and solutions

    SciTech Connect

    Bann, J.; Irisarri, G.; Kirschen, D.; Miller, B.; Mokhtari, S.

    1996-02-01

    This paper discusses the issues which must be addressed when integrating Artificial Intelligence (AI) and, in particular, expert system applications in an Energy Management System (EMS) environment. It is argued that these issues can be resolved by creating an environment which supports all the interfaces between the Artificial Intelligence (AI) applications and the EMS. This environment should also be responsible for maintaining a model of the power system common to all the AI applications. Once this environment has been created, AI applications can be easily plugged into the EMS. The design of such an environment is described and case studies of its implementation are provided to illustrate its flexibility.

  6. Stochastic EM algorithm for nonlinear state estimation with model uncertainties

    NASA Astrophysics Data System (ADS)

    Zia, Amin; Kirubarajan, Thiagalingam; Reilly, James P.; Shirani, Shahram

    2004-01-01

    In most solutions to state estimation problems like, for example, target tracking, it is generally assumed that the state evolution and measurement models are known a priori. The model parameters include process and measurement matrices or functions as well as the corresponding noise statistics. However, there are situations where the model parameters are not known a priori or are known only partially (i.e., with some uncertainty). Moreover, there are situations where the measurement is biased. In these scenarios, standard estimation algorithms like the Kalman filter and the extended Kalman Filter (EKF), which assume perfect knowledge of the model parameters, are not accurate. In this paper, the problem with uncertain model parameters is considered as a special case of maximum likelihood estimation with incomplete-data, for which a standard solution called the expectation-maximization (EM) algorithm exists. In this paper a new extension to the EM algorithm is proposed to solve the more general problem of joint state estimation and model parameter identification for nonlinear systems with possibly non-Gaussian noise. In the expectation (E) step, it is shown that the best variational distribution over the state variables is the conditional posterior distribution of states given all the available measurements and inputs. Therefore, a particular type of particle filter is used to estimate and update the posterior distribution. In the maximization (M) step the nonlinear measurement process parameters are approximated using a nonlinear regression method for adjusting the parameters of a mixture of Gaussians (MofG). The proposed algorithm is used to solve a nonlinear bearing-only tracking problem similar to the one reported recently with uncertain measurement process. It is shown that the algorithm is capable of accurately tracking the state vector while identifying the unknown measurement dynamics. Simulation results show the advantages of the new technique over standard

  7. Stochastic EM algorithm for nonlinear state estimation with model uncertainties

    NASA Astrophysics Data System (ADS)

    Zia, Amin; Kirubarajan, Thiagalingam; Reilly, James P.; Shirani, Shahram

    2003-12-01

    In most solutions to state estimation problems like, for example, target tracking, it is generally assumed that the state evolution and measurement models are known a priori. The model parameters include process and measurement matrices or functions as well as the corresponding noise statistics. However, there are situations where the model parameters are not known a priori or are known only partially (i.e., with some uncertainty). Moreover, there are situations where the measurement is biased. In these scenarios, standard estimation algorithms like the Kalman filter and the extended Kalman Filter (EKF), which assume perfect knowledge of the model parameters, are not accurate. In this paper, the problem with uncertain model parameters is considered as a special case of maximum likelihood estimation with incomplete-data, for which a standard solution called the expectation-maximization (EM) algorithm exists. In this paper a new extension to the EM algorithm is proposed to solve the more general problem of joint state estimation and model parameter identification for nonlinear systems with possibly non-Gaussian noise. In the expectation (E) step, it is shown that the best variational distribution over the state variables is the conditional posterior distribution of states given all the available measurements and inputs. Therefore, a particular type of particle filter is used to estimate and update the posterior distribution. In the maximization (M) step the nonlinear measurement process parameters are approximated using a nonlinear regression method for adjusting the parameters of a mixture of Gaussians (MofG). The proposed algorithm is used to solve a nonlinear bearing-only tracking problem similar to the one reported recently with uncertain measurement process. It is shown that the algorithm is capable of accurately tracking the state vector while identifying the unknown measurement dynamics. Simulation results show the advantages of the new technique over standard

  8. DOE-EM-45 PACKAGING OPERATIONS AND MAINTENANCE COURSE

    SciTech Connect

    Watkins, R.; England, J.

    2010-05-28

    Savannah River National Laboratory - Savannah River Packaging Technology (SRNL-SRPT) delivered the inaugural offering of the Packaging Operations and Maintenance Course for DOE-EM-45's Packaging Certification Program (PCP) at the University of South Carolina Aiken on September 1 and 2, 2009. Twenty-nine students registered, attended, and completed this training. The DOE-EM-45 Packaging Certification Program (PCP) sponsored the presentation of a new training course, Packaging Maintenance and Operations, on September 1-2, 2009 at the University of South Carolina Aiken (USC-Aiken) campus in Aiken, SC. The premier offering of the course was developed and presented by the Savannah River National Laboratory, and attended by twenty-nine students across the DOE, NNSA and private industry. This training informed package users of the requirements associated with handling shipping containers at a facility (user) level and provided a basic overview of the requirements typically outlined in Safety Analysis Report for Packaging (SARP) Chapters 1, 7, and 8. The course taught packaging personnel about the regulatory nature of SARPs to help reduce associated and often costly packaging errors. Some of the topics covered were package contents, loading, unloading, storage, torque requirements, maintaining records, how to handle abnormal conditions, lessons learned, leakage testing (including demonstration), and replacement parts. The target audience for this course was facility operations personnel, facility maintenance personnel, and field quality assurance personnel who are directly involved in the handling of shipping containers. The training also aimed at writers of SARP Chapters 1, 7, and 8, package designers, and anyone else involved in radioactive material packaging and transportation safety. Student feedback and critiques of the training were very positive. SRNL will offer the course again at USC Aiken in September 2010.

  9. BVR{sub c}I{sub c} OBSERVATIONS AND ANALYSES OF THE DWARF DETACHED BINARY V1043 CASSIOPEIA AND A COMMENT ON PRECONTACT W UMa'S

    SciTech Connect

    Samec, R. G.; Smith, P. M.; Chamberlain, H.; Faulkner, D. R.; Van Hamme, W.

    2013-01-01

    Complete Bessel BVR{sub c}I{sub c} light curves of V1043 Cassiopeia [2MASS J00371195+5301324, Mis V1292, USNO-A2.0 1425-00875743, {alpha}(2000) = 00{sup h}37{sup m}11.{sup s}95, {delta}(2000) = +53 Degree-Sign 01'32.''5] are analyzed. The system is a member of the small group of pre-contact W UMa binaries (PCWBs). Its light curve has the appearance of an Algol (EA) light curve, however it is made up of dwarf solar type components in a detached mode with a period of only 0.6616 days. The analysis includes a period study, an improved ephemeris, a mass ratio search, and a simultaneous BVR{sub c}I{sub c} Wilson-Devinney solution. We document about 20 other PCWBs given in the literature. Several have RS CVn-like properties.

  10. Photometric observations and light curve solutions of the W UMa stars NSVS 2244206, NSVS 908513, CSS J004004.7+385531 and VSX J062624.4+570907

    NASA Astrophysics Data System (ADS)

    Kjurkchieva, Diana Petrova; Popov, Velimir Angelov; Vasileva, Doroteya Lyubenova; Petrov, Nikola Ivanov

    2016-09-01

    Photometric observations in Sloan g‧ and i‧ bands of four W UMa stars, NSVS 2244206, NSVS 908513, CSS J004004.7+385531 and VSX J062624.4+570907, are presented. The light curve solutions reveal that all targets have overcontact configurations with fillout factors within 0.15–0.26. Their components are G-K spectral types and are almost in thermal contact. They are also relatively close in size and luminosity: the radius ratios r2/r1 are within 0.75–0.90 the luminosity ratios l2/l1 are within 0.53–0.63. The results of the light curve solution of CSS J004004.7+385531 imply the weak limb-darkening effect of its primary component and possible presence of additional absorbing features in the system.

  11. Vibrational symmetry classification and torsional tunneling splitting patterns in G6(EM), G12, and G36(EM) molecules

    NASA Astrophysics Data System (ADS)

    Lattanzi, F.; di Lauro, C.

    It is shown that the torsional splitting patterns in methanol-like molecules, with the excitation of small amplitude vibrational modes in the methyl group, are determined by mechanisms that can be formulated in an almost identical fashion to that for ethane-like molecules. This is achieved by treating ethane-like molecules by the internal axis method (IAM) and methanol-like molecules by the principal axis method (PAM) or rho-axis method (RAM). Using the extended molecular groups G6(EM) or C6v(M) for methanol and G36(EM) for ethane, vibrations perpendicular to the internal rotation axis are conveniently described by modes of higher degeneracy (E for methanol and Gs for ethane) in the absence of coupling of top and frame. Head-tail coupling operators, except the cos-type barrier terms, lower the degeneracy, causing vibrational splittings. Coupled vibrational pairs with torsional splitting patterns that we call 'regular' (pure A1, A2 pairs for methanol and pure E1d, E2d pairs for ethane) or 'inverted' (pure B1, B2 pairs for methanol and pure E1s, E2s pairs for ethane) can be formed as limit cases. Actual splitting patterns occur between the above limits, and are basically determined by torsional Coriolis coupling, which can tune more or less to resonance pairs of uncoupled basis levels linked by specific head-tail coupling operators. The inversion of torsional splitting patterns, observed in perpendicular vibrational modes of the methyl group of methanol, can be predicted by these theoretical considerations. Similar considerations apply to molecules of G12 symmetry.

  12. Aquisição de Estreptococos Mutans e Desenvolvimento de Cárie Dental em Primogênitos

    PubMed Central

    NOCE, Erica; RUBIRA, Cassia Maria Fischer; da Silva ROSA, Odila Pereira; da SILVA, Salete Moura Bonifácio; BRETZ, Walter Antonio

    2011-01-01

    Objetivo Avaliar o momento de aquisição de estreptococos mutans (EM), desenvolvimento de cárie dental e as variáveis a eles associadas no decorrer de 23 meses, em primogênitos de famílias de baixo nível socioeconômico, desde os sete meses de idade. Método A amostra foi selecionada com base em mães densamente colonizadas por EM, incluindo todos os membros de 14 famílias que conviviam na mesma casa. Foram envolvidos no estudo 14 mães, pais e primogênitos e 8 parentes, na maioria avós. Exames clínicos e radiográficos iniciais determinaram os índices de cárie e condição periodontal dos adultos. Contagens de EM foram feitas em todos os adultos nas duas primeiras visitas. Nas crianças foram avaliados os níveis de EM, o número de dentes e de cáries, em quatro visitas. Resultados A prevalência de EM nos adultos foi alta, estando ausente em apenas um dos pais. EM foram detectados em 1, 2, 3 e 10 crianças, respectivamente nas visitas #1, 2, 3 e 4. A cárie dental foi detectada em apenas três crianças na última visita (aos 30 meses de idade), as quais apresentaram escores de EM significantemente maiores que as crianças sem cárie, na mesma visita. Conclusão Exclusivamente a condição social de baixa renda e mães densamente colonizadas por EM não são sinônimo de colonização precoce e alta atividade de cárie em crianças cuidadas em casa. O desenvolvimento de cárie está significantemente associado a escores elevados de EM nas crianças. PMID:22022218

  13. EMDataBank.org: unified data resource for CryoEM

    PubMed Central

    Lawson, Catherine L.; Baker, Matthew L.; Best, Christoph; Bi, Chunxiao; Dougherty, Matthew; Feng, Powei; van Ginkel, Glen; Devkota, Batsal; Lagerstedt, Ingvar; Ludtke, Steven J.; Newman, Richard H.; Oldfield, Tom J.; Rees, Ian; Sahni, Gaurav; Sala, Raul; Velankar, Sameer; Warren, Joe; Westbrook, John D.; Henrick, Kim; Kleywegt, Gerard J.; Berman, Helen M.; Chiu, Wah

    2011-01-01

    Cryo-electron microscopy reconstruction methods are uniquely able to reveal structures of many important macromolecules and macromolecular complexes. EMDataBank.org, a joint effort of the Protein Data Bank in Europe (PDBe), the Research Collaboratory for Structural Bioinformatics (RCSB) and the National Center for Macromolecular Imaging (NCMI), is a global ‘one-stop shop’ resource for deposition and retrieval of cryoEM maps, models and associated metadata. The resource unifies public access to the two major archives containing EM-based structural data: EM Data Bank (EMDB) and Protein Data Bank (PDB), and facilitates use of EM structural data of macromolecules and macromolecular complexes by the wider scientific community. PMID:20935055

  14. Analysis of the electrochemistry of hemes with Ems spanning 800 mV

    PubMed Central

    Zheng, Zhong; Gunner, M. R.

    2009-01-01

    The free energy of heme reduction in different proteins is found to vary over more than 18 kcal/mol. It is a challenge to determine how proteins manage to achieve this enormous range of Ems with a single type of redox cofactor. Proteins containing 141 unique hemes of a-, b-, and c-type, with bis-His, His-Met, and aquo-His ligation were calculated using Multi-Conformation Continuum Electrostatics (MCCE). The experimental Ems range over 800 mV from −350 mV in cytochrome c3 to 450 mV in cytochrome c peroxidase (vs. SHE). The quantitative analysis of the factors that modulate heme electrochemistry includes the interactions of the heme with its ligands, the solvent, the protein backbone, and sidechains. MCCE calculated Ems are in good agreement with measured values. Using no free parameters the slope of the line comparing calculated and experimental Ems is 0.73 (R2 = 0.90), showing the method accounts for 73% of the observed Em range. Adding a +160 mV correction to the His-Met c-type hemes yields a slope of 0.97 (R2 = 0.93). With the correction 65% of the hemes have an absolute error smaller than 60 mV and 92% are within 120 mV. The overview of heme proteins with known structures and Ems shows both the lowest and highest potential hemes are c-type, whereas the b-type hemes are found in the middle Em range. In solution, bis-His ligation lowers the Em by ≈205 mV relative to hemes with His-Met ligands. The bis-His, aquo-His, and His-Met ligated b-type hemes all cluster about Ems which are ≈200 mV more positive in protein than in water. In contrast, the low potential bis-His c-type hemes are shifted little from in solution, whereas the high potential His-Met c-type hemes are raised by ≈300 mV from solution. The analysis shows that no single type of interaction can be identified as the most important in setting heme electrochemistry in proteins. For example, the loss of solvation (reaction field) energy, which raises the Em, has been suggested to be a major factor in

  15. Volta phase plate cryo-EM of the small protein complex Prx3

    PubMed Central

    Khoshouei, Maryam; Radjainia, Mazdak; Phillips, Amy J.; Gerrard, Juliet A.; Mitra, Alok K.; Plitzko, Jürgen M.; Baumeister, Wolfgang; Danev, Radostin

    2016-01-01

    Cryo-EM of large, macromolecular assemblies has seen a significant increase in the numbers of high-resolution structures since the arrival of direct electron detectors. However, sub-nanometre resolution cryo-EM structures are rare compared with crystal structure depositions, particularly for relatively small particles (<400 kDa). Here we demonstrate the benefits of Volta phase plates for single-particle analysis by time-efficient cryo-EM structure determination of 257 kDa human peroxiredoxin-3 dodecamers at 4.4 Å resolution. The Volta phase plate improves the applicability of cryo-EM for small molecules and accelerates structure determination. PMID:26817416

  16. 7. PHOTOCOPY, ELEVATIONS FOR E.M. BARRACKS, N.C.O. AND OFFICERS QUARTERS. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. PHOTOCOPY, ELEVATIONS FOR E.M. BARRACKS, N.C.O. AND OFFICERS QUARTERS. - NIKE Missile Base SL-40, Barracks No. 1, North end of base, southest of Basketball Court & northwest of Barracks No. 2, Hecker, Monroe County, IL

  17. The development of cryo-EM into a mainstream structural biology technique

    PubMed Central

    Nogales, Eva

    2016-01-01

    Single-particle cryo-electron microscopy (cryo-EM) has emerged over the last two decades as a technique capable of studying challenging systems that otherwise defy structural characterization. Recent technical advances have resulted in a ‘quantum leap’ in applicability, throughput and achievable resolution that has gained this technique worldwide attention. Here I discuss some of the major historical landmarks in the development of the cryo-EM field, ultimately leading to its present success. PMID:27110629

  18. The front lines of domestic violence. Training model for rural EMS personnel.

    PubMed

    Hall, Marcia; Becker, Vanessa

    2002-09-01

    1. Domestic violence is a major public health problem requiring committed, coordinated community response. 2. Domestic violence is a significant cause of morbidity and mortality for women and children in the United States. 3. EMS personnel play a frontline role in the critical response and prevention of domestic violence. 4. EMS education and training are requisite for safe, effective responses to domestic violence in rural communities. PMID:12235968

  19. Space resolution obtained with a highly segmented SCIFI e.m. calorimeter

    NASA Astrophysics Data System (ADS)

    Bertino, M.; Bini, C.; De Pedis, D.; De Zorzi, G.; Diambrini Palazzi, G.; Di Cosimo, G.; Di Domenico, A.; Gauzzi, P.; Zanello, D.

    1992-05-01

    During the setting up of the LEP-5 experiment, we tested a longitudinal SCIFI e.m. calorimeter, having a module cross area 25 × 25 mm 2 and 12.5 × 12.5 mm 2 for large and small modules respectively. The results were obtained with 10 and 50 GeV electrons, and concern the impact point resolution and the transverse distribution of the e.m. shower energy inside the calorimeter.

  20. Effects of Loaded Squat Exercise with and without Application of Superimposed EMS on Physical Performance.

    PubMed

    Wirtz, Nicolas; Zinner, Christoph; Doermann, Ulrike; Kleinoeder, Heinz; Mester, Joachim

    2016-03-01

    The aim of the present study was to investigate the effects of a multiple set squat exercise training intervention with superimposed electromyostimulation (EMS) on strength and power, sprint and jump performance. Twenty athletes from different disciplines participated and were divided into two groups: strength training (S) or strength training with superimposed EMS (S+E). Both groups completed the same training program twice a week over a six week period consisting of four sets of the 10 repetition maximum of back squats. Additionally, the S+E group had EMS superimposed to the squat exercise with simultaneous stimulation of leg and trunk muscles. EMS intensity was adjusted to 70% of individual pain threshold to ensure dynamic movement. Strength and power of different muscle groups, sprint, and vertical jump performance were assessed one week before (pre), one week after (post) and three weeks (re) following the training period. Both groups showed improvements in leg press strength and power, countermovement and squat jump performance and pendulum sprint (p < 0.05), with no changes for linear sprint. Differences between groups were only evident at the leg curl machine with greater improvements for the S+E group (p < 0.05). Common squat exercise training and squat exercise with superimposed EMS improves maximum strength and power, as well as jumping abilities in athletes from different disciplines. The greater improvements in strength performance of leg curl muscles caused by superimposed EMS with improvements in strength of antagonistic hamstrings in the S+E group are suggesting the potential of EMS to unloaded (antagonistic) muscle groups. Key pointsSimilar strength adaptations occurred after a 6 week 10 RM back squat exercise program with superimposed EMS (S+E) and 10 RM back squat exercise (S) alone.Specific adaptations for S+E at the leg curl muscles were evident.S and S+E improved SJ, CMJ and pendulum sprint performance.No improvement occurred in linear sprint

  1. Effects of Loaded Squat Exercise with and without Application of Superimposed EMS on Physical Performance

    PubMed Central

    Wirtz, Nicolas; Zinner, Christoph; Doermann, Ulrike; Kleinoeder, Heinz; Mester, Joachim

    2016-01-01

    The aim of the present study was to investigate the effects of a multiple set squat exercise training intervention with superimposed electromyostimulation (EMS) on strength and power, sprint and jump performance. Twenty athletes from different disciplines participated and were divided into two groups: strength training (S) or strength training with superimposed EMS (S+E). Both groups completed the same training program twice a week over a six week period consisting of four sets of the 10 repetition maximum of back squats. Additionally, the S+E group had EMS superimposed to the squat exercise with simultaneous stimulation of leg and trunk muscles. EMS intensity was adjusted to 70% of individual pain threshold to ensure dynamic movement. Strength and power of different muscle groups, sprint, and vertical jump performance were assessed one week before (pre), one week after (post) and three weeks (re) following the training period. Both groups showed improvements in leg press strength and power, countermovement and squat jump performance and pendulum sprint (p < 0.05), with no changes for linear sprint. Differences between groups were only evident at the leg curl machine with greater improvements for the S+E group (p < 0.05). Common squat exercise training and squat exercise with superimposed EMS improves maximum strength and power, as well as jumping abilities in athletes from different disciplines. The greater improvements in strength performance of leg curl muscles caused by superimposed EMS with improvements in strength of antagonistic hamstrings in the S+E group are suggesting the potential of EMS to unloaded (antagonistic) muscle groups. Key points Similar strength adaptations occurred after a 6 week 10 RM back squat exercise program with superimposed EMS (S+E) and 10 RM back squat exercise (S) alone. Specific adaptations for S+E at the leg curl muscles were evident. S and S+E improved SJ, CMJ and pendulum sprint performance. No improvement occurred in linear

  2. ModEM: A modular system for inversion of elecgtromagnetic geophysical data

    NASA Astrophysics Data System (ADS)

    Egbert, G. D.; Kelbert, A.; Meqbel, N.; Weng, A.

    2010-12-01

    We have developed a modular system of computer codes for inversion of electromagnetic (EM) geophysical data (ModEM). ModEM allows for rapid adaptation of inversion algorithms developed for one purpose (e.g., three-dimensional magnetotellurics (MT)) to other EM problems (e.g., controlled source EM). The modular approach can also simplify maintenance of the inversion code, as well as development of new capabilities -- e.g., allowing for new data types such as the inter-site transfer functions in MT, or modifying model regularization. Basic data objects (model parameters, solution vectors, data vectors) are treated as abstract data types, with a standard set of methods developed for each class, including creation and destruction, and, as appropriate, linear algebra or other vector space methods. Operators required for gradient computations are developed as mappings between these basic object classes. Only these abstract data objects and mappings are manipulated by higher level Jacobian and inversion routines, with no reference to the problem specific details required for a specific EM method, or for the numerical implementation of the forward solver. Required problem-specific components are instantiated at the lowest levels of the system, with details hidden from generic top-level routines by an interface layer. Parallelization using MPI has been implemented at the top level, and is thus applicable to any problem embedded in ModEM. To illustrate the flexibility of the system, we consider applications to two- and three-dimensional MT inversion, as well as simple controlled source EM problems.

  3. The Soils and Groundwater – EM-20 S&T Roadmap Quality Assurance Project Plan

    SciTech Connect

    Fix, N. J.

    2008-02-11

    The Soils and Groundwater – EM-20 Science and Technology Roadmap Project is a U.S. Department of Energy, Office of Environmental Management-funded initiative designed to develop new methods, strategies and technology for characterizing, modeling, remediating, and monitoring soils and groundwater contaminated with metals, radionuclides, and chlorinated organics. This Quality Assurance Project Plan provides the quality assurance requirements and processes that will be followed by EM-20 Roadmap Project staff.

  4. Pre-flight risk assessment in emergency medical service (EMS) helicopters

    NASA Technical Reports Server (NTRS)

    Shively, Robert J.

    1990-01-01

    A preflight risk assessment system (SAFE) was developed at NASA-Ames Research Center for civil EMS operations to assist pilots in making a decision objectively to accept or decline a mission. The ability of the SAFE system to predict risk profiles was examined at an EMS operator. Results of this field study showed that the usefulness of SAFE was largely dependent on the type of mission flown.

  5. Single-particle cryo-EM data acquisition by using direct electron detection camera.

    PubMed

    Wu, Shenping; Armache, Jean-Paul; Cheng, Yifan

    2016-02-01

    Recent advances in single-particle electron cryo-microscopy (cryo-EM) were largely facilitated by the application of direct electron detection cameras. These cameras feature not only a significant improvement in detective quantum efficiency but also a high frame rate that enables images to be acquired as 'movies' made of stacks of many frames. In this review, we discuss how the applications of direct electron detection cameras in cryo-EM have changed the way the data are acquired. PMID:26546989

  6. Using Molecular Simulation to Model High-Resolution Cryo-EM Reconstructions.

    PubMed

    Kirmizialtin, Serdal; Loerke, Justus; Behrmann, Elmar; Spahn, Christian M T; Sanbonmatsu, Karissa Y

    2015-01-01

    An explosion of new data from high-resolution cryo-electron microscopy (cryo-EM) studies has produced a large number of data sets for many species of ribosomes in various functional states over the past few years. While many methods exist to produce structural models for lower resolution cryo-EM reconstructions, high-resolution reconstructions are often modeled using crystallographic techniques and extensive manual intervention. Here, we present an automated fitting technique for high-resolution cryo-EM data sets that produces all-atom models highly consistent with the EM density. Using a molecular dynamics approach, atomic positions are optimized with a potential that includes the cross-correlation coefficient between the structural model and the cryo-EM electron density, as well as a biasing potential preserving the stereochemistry and secondary structure of the biomolecule. Specifically, we use a hybrid structure-based/ab initio molecular dynamics potential to extend molecular dynamics fitting. In addition, we find that simulated annealing integration, as opposed to straightforward molecular dynamics integration, significantly improves performance. We obtain atomistic models of the human ribosome consistent with high-resolution cryo-EM reconstructions of the human ribosome. Automated methods such as these have the potential to produce atomistic models for a large number of ribosome complexes simultaneously that can be subsequently refined manually. PMID:26068751

  7. Fusion to a homo-oligomeric scaffold allows cryo-EM analysis of a small protein.

    PubMed

    Coscia, Francesca; Estrozi, Leandro F; Hans, Fabienne; Malet, Hélène; Noirclerc-Savoye, Marjolaine; Schoehn, Guy; Petosa, Carlo

    2016-01-01

    Recent technical advances have revolutionized the field of cryo-electron microscopy (cryo-EM). However, most monomeric proteins remain too small (<100 kDa) for cryo-EM analysis. To overcome this limitation, we explored a strategy whereby a monomeric target protein is genetically fused to a homo-oligomeric scaffold protein and the junction optimized to allow the target to adopt the scaffold symmetry, thereby generating a chimeric particle suitable for cryo-EM. To demonstrate the concept, we fused maltose-binding protein (MBP), a 40 kDa monomer, to glutamine synthetase, a dodecamer formed by two hexameric rings. Chimeric constructs with different junction lengths were screened by biophysical analysis and negative-stain EM. The optimal construct yielded a cryo-EM reconstruction that revealed the MBP structure at sub-nanometre resolution. These findings illustrate the feasibility of using homo-oligomeric scaffolds to enable cryo-EM analysis of monomeric proteins, paving the way for applying this strategy to challenging structures resistant to crystallographic and NMR analysis. PMID:27485862

  8. New Developments in the Technology Readiness Assessment Process in US DOE-EM - 13247

    SciTech Connect

    Krahn, Steven; Sutter, Herbert; Johnson, Hoyt

    2013-07-01

    A Technology Readiness Assessment (TRA) is a systematic, metric-based process and accompanying report that evaluates the maturity of the technologies used in systems; it is designed to measure technology maturity using the Technology Readiness Level (TRL) scale pioneered by the National Aeronautics and Space Administration (NASA) in the 1980's. More recently, DoD has adopted and provided systematic guidance for performing TRAs and determining TRLs. In 2007 the GAO recommended that the DOE adopt the NASA/DoD methodology for evaluating technology maturity. Earlier, in 2006-2007, DOE-EM had conducted pilot TRAs on a number of projects at Hanford and Savannah River. In March 2008, DOE-EM issued a process guide, which established TRAs as an integral part of DOE-EM's Project Management Critical Decision Process. Since the development of its detailed TRA guidance in 2008, DOE-EM has continued to accumulate experience in the conduct of TRAs and the process for evaluating technology maturity. DOE has developed guidance on TRAs applicable department-wide. DOE-EM's experience with the TRA process, the evaluations that led to recently developed proposed revisions to the DOE-EM TRA/TMP Guide; the content of the proposed changes that incorporate the above lessons learned and insights are described. (authors)

  9. Visualizing Proteins and Macromolecular Complexes by Negative Stain EM: from Grid Preparation to Image Acquisition

    PubMed Central

    Booth, David S.; Avila-Sakar, Agustin; Cheng, Yifan

    2011-01-01

    Single particle electron microscopy (EM), of both negative stained or frozen hydrated biological samples, has become a versatile tool in structural biology 1. In recent years, this method has achieved great success in studying structures of proteins and macromolecular complexes 2, 3. Compared with electron cryomicroscopy (cryoEM), in which frozen hydrated protein samples are embedded in a thin layer of vitreous ice 4, negative staining is a simpler sample preparation method in which protein samples are embedded in a thin layer of dried heavy metal salt to increase specimen contrast 5. The enhanced contrast of negative stain EM allows examination of relatively small biological samples. In addition to determining three-dimensional (3D) structure of purified proteins or protein complexes 6, this method can be used for much broader purposes. For example, negative stain EM can be easily used to visualize purified protein samples, obtaining information such as homogeneity/heterogeneity of the sample, formation of protein complexes or large assemblies, or simply to evaluate the quality of a protein preparation. In this video article, we present a complete protocol for using an EM to observe negatively stained protein sample, from preparing carbon coated grids for negative stain EM to acquiring images of negatively stained sample in an electron microscope operated at 120kV accelerating voltage. These protocols have been used in our laboratory routinely and can be easily followed by novice users. PMID:22215030

  10. An erythromycin derivative, EM-523, induces motilin-like gastrointestinal motility in dogs.

    PubMed

    Inatomi, N; Satoh, H; Maki, Y; Hashimoto, N; Itoh, Z; Omura, S

    1989-11-01

    The effect of an erythromycin derivative, EM-523, on gastrointestinal motility was investigated in conscious dogs and compared with that of motilin cisapride, trimebutine and metoclopramide. In the fasting state, EM-523 given i.v. or i.d. at 3 micrograms/kg or more induced contractions in the stomach that migrated along the small intestine. The pattern of the contractions was very similar to that induced by motilin. In the digestive state, EM-523 increased the amplitude of gastric contractions. Cisapride and metoclopramide increased gastrointestinal motility both in the fasting and digestive states; however, their contractile pattern was different from that of EM-523. Trimebutine did not induce gastric motility in the fasting state but rather decreased gastric motility in the digestive state. The contractions induced by EM-523 and motilin were inhibited by atropine but were not affected by naloxone, suggesting that the cholinergic pathway is important in the exertion of their action. These results indicate that EM-523 mimics motilin in stimulating gastrointestinal motility and that this agent may be useful treat gastrointestinal disorders such as gastric stasis, gastroesophageal reflux, and postoperative ileus, and so forth. PMID:2810120

  11. Reservoir characterization and process monitoring with EM methods. 1994 Annual report

    SciTech Connect

    Wilt, M.

    1995-05-01

    During the past five years at Lawrence Livermore National Laboratory (LLNL) the authors have applied the EM induction method to the problem of petroleum reservoir characterization and enhanced oil recovery (EOR) monitoring. The goal is to develop practical tools for determining the electrical resistivity distribution between boreholes at a useful scale for reservoir characterization. During FY94 the authors conducted their largest field test to date. They applied crosshole and surface-to-borehole EM techniques to reservoir characterization at the Los Hills No. 3 oil field making three sets of measurements during the initial phase of the steam drive.From these data they were able to determine the resistivity and configuration of the oil sands, between the observation wells, and provide an image of the subsurface resistivity changes due to the steam drive. They also conducted a waterflood experiment at the Richmond Field Station facility using the borehole-to-surface EM technique. For this test they injected a small quantity of saltwater, and applied the Em technique to monitor the progress of the injected plume. Data collection for this experiment is complete but the results are yet to be interpreted. Finally, a project to understand EM propagation through steel casing was initiated in 1994. The goals of the experiment are to determine the limits and applications for crosswell EM surveys through steel well casing.

  12. An Uncertainty Analysis for Predicting Soil Profile Salinity Using EM Induction Data

    NASA Astrophysics Data System (ADS)

    Huang, Jingyi; Monteiro Santos, Fernando; Triantafilis, John

    2016-04-01

    Proximal soil sensing techniques such as electromagnetic (EM) induction have been used to identify and map the areal variation of average soil properties. However, soil varies with depth owing to the action of various soil forming factors (e.g., parent material and topography). In this work we collected EM data using an EM38 and EM34 meter along a 22-km transect in the Trangie District, Australia.We jointly inverted these data using EM4Soil software and compare our 2-dimensional model of true electrical conductivity (sigma - mS/m) with depth against measured electrical conductivity of a saturated soil-paste extract (ECe - dS/m) at depth of 0-16 m. Through the use of a linear regression (LR) model and by varying forward modelling algorithms (cumulative function and full solution), inversion algorithms (S1 and S2), and damping factor (lambda) we determined a suitable electromagnetic conductivity image (EMCI) which was optimal when using the full solution, S2 and lambda = 0.6. To evaluate uncertainty of the inversion process and the LR model, we conducted an uncertainty analysis. The distribution of the model misfit shows the largest uncertainty caused by inversion (mostly due to EM34-40) occurs at deeper profiles while the largest uncertainty of the LR model occurs where the soil profile is most saline. These uncertainty maps also illustrate us how the model accuracy can be improved in the future.

  13. Operation Protective Edge - A Unique Challenge for a Civilian EMS Agency.

    PubMed

    Jaffe, Eli; Strugo, Refael; Wacht, Oren

    2015-10-01

    During July through August 2014, Operation Protective Edge, a military conflict between Israel and the Hamas regime in Gaza, dramatically affected both populations. Magen David Adom (MDA), the Israeli national Emergency Medical Service (EMS) and a member of the Red Cross, faced a unique challenge during the conflict: to continue providing crucial service to the entire civilian population of Israel, which was under constant missile threat. This challenge included not only providing immediate care for routine EMS calls under missile threat, but also preparing and delivering immediate care to civilians injured in attacks on major cities, as well as small communities, in Israel. This task is a challenge for a civilian EMS agency that normally operates in a non-military environment, yet, in an instant, must enhance its capability to respond to a considerable threat to its population. During Operation Protective Edge, MDA provided care for 842 wounded civilians and utilized a significant amount of its resources. Providing EMS services for a civilian population in a mixed civilian/military scenario is a challenging task on a national level for an EMS system, especially when the threat lasts for weeks. This report describes MDA's preparedness and operations during Operation Protective Edge, and the unique EMS challenges and dilemmas the agency faced. PMID:26323985

  14. High-speed computation of the EM algorithm for PET image reconstruction

    SciTech Connect

    Rajan, K.; Patnaik, L.M.; Ramakrishna, J. )

    1994-10-01

    The PET image reconstruction based on the EM algorithm has several attractive advantages over the conventional convolution backprojection algorithms. However, two major drawbacks have impeded the routine use of the EM algorithm, namely, the long computational time due to slow convergence and the large memory required for the storage of the image, projection data and the probability matrix. In this study, the authors attempts to solve these two problems by parallelizing the EM algorithm on a multiprocessor system. The authors have implemented an extended hypercube (EH) architecture for the high-speed computation of the EM algorithm using the commercially available fast floating point digital signal processor (DSP) chips as the processing elements (PEs). The authors discuss and compare the performance of the EM algorithm on a 386/387 machine, CD 4360 mainframe, and on the EH system. The results show that the computational speed performance of an EH using DSP chips as PEs executing the EM image reconstruction algorithm is about 130 times better than that of the CD 4360 mainframe. The EH topology is expandable with more number of PEs.

  15. Fusion to a homo-oligomeric scaffold allows cryo-EM analysis of a small protein

    PubMed Central

    Coscia, Francesca; Estrozi, Leandro F.; Hans, Fabienne; Malet, Hélène; Noirclerc-Savoye, Marjolaine; Schoehn, Guy; Petosa, Carlo

    2016-01-01

    Recent technical advances have revolutionized the field of cryo-electron microscopy (cryo-EM). However, most monomeric proteins remain too small (<100 kDa) for cryo-EM analysis. To overcome this limitation, we explored a strategy whereby a monomeric target protein is genetically fused to a homo-oligomeric scaffold protein and the junction optimized to allow the target to adopt the scaffold symmetry, thereby generating a chimeric particle suitable for cryo-EM. To demonstrate the concept, we fused maltose-binding protein (MBP), a 40 kDa monomer, to glutamine synthetase, a dodecamer formed by two hexameric rings. Chimeric constructs with different junction lengths were screened by biophysical analysis and negative-stain EM. The optimal construct yielded a cryo-EM reconstruction that revealed the MBP structure at sub-nanometre resolution. These findings illustrate the feasibility of using homo-oligomeric scaffolds to enable cryo-EM analysis of monomeric proteins, paving the way for applying this strategy to challenging structures resistant to crystallographic and NMR analysis. PMID:27485862

  16. Method for estimating dynamic EM tracking accuracy of surgical navigation tools

    NASA Astrophysics Data System (ADS)

    Nafis, Christopher; Jensen, Vern; Beauregard, Lee; Anderson, Peter

    2006-03-01

    Optical tracking systems have been used for several years in image guided medical procedures. Vendors often state static accuracies of a single retro-reflective sphere or LED. Expensive coordinate measurement machines (CMM) are used to validate the positional accuracy over the specified working volume. Users are interested in the dynamic accuracy of their tools. The configuration of individual sensors into a unique tool, the calibration of the tool tip, and the motion of the tool contribute additional errors. Electromagnetic (EM) tracking systems are considered an enabling technology for many image guided procedures because they are not limited by line-of-sight restrictions, take minimum space in the operating room, and the sensors can be very small. It is often difficult to quantify the accuracy of EM trackers because they can be affected by field distortion from certain metal objects. Many high-accuracy measurement devices can affect the EM measurements being validated. EM Tracker accuracy tends to vary over the working volume and orientation of the sensors. We present several simple methods for estimating the dynamic accuracy of EM tracked tools. We discuss the characteristics of the EM Tracker used in the GE Healthcare family of surgical navigation systems. Results for other tracking systems are included.

  17. EM techniques for archaeological laboratory experiments: preliminary results

    NASA Astrophysics Data System (ADS)

    Capozzoli, Luigi; De Martino, Gregory; Giampaolo, Valeria; Raffaele, Luongo; Perciante, Felice; Rizzo, Enzo

    2015-04-01

    The electromagnetic techniques (EM) are based on the investigation of subsoil geophysical parameters and in the archaeological framework they involve in studying contrasts between the buried cultural structures and the surrounding materials. Unfortunately, the geophysical contrast between archaeological features and surrounding soils sometimes are difficult to define due to problems of sensitivity and resolution both related on the characteristic of the subsoil and the geophysical methods. For this reason an experimental activity has been performed in the Hydrogeosite laboratory addressed on the assessment of the capability of geophysical techniques to detect archeological remains placed in the humid/saturated subsoil. At Hydrogeosite Laboratory of CNR-IMAA, a large scale sand-box is located, consisting on a pool shape structures of 230m3 where archaeological remains have been installed . The remains are relative to a living environment and burial of Roman times (walls, tombs, roads, harbour, etc.) covered by sediments. In order to simulate lacustrine and wetland condition and to simulate extreme events (for example underwater landslide, fast natural erosion coast, etc.) the phreatic level was varied and various acquisitions for the different scenarios were performed. In order to analyze the EM behavior of the buried small archaeological framework, ground penetrating radar (GPR) and electrical resistivity tomographies were performed. With GPR, analysis in time domain and frequency domain were performed and coupled to information obtained through resistivity analysis with the support of numerical simulations used to compare the real data with those modeled. A dense grid was adopted for 400 and 900 MHz e-m acquisitions in both the directions, the maximum depth of investigation was limited and less than 3 meters. The same approach was used for ERT acquisition where different array are employed, in particular 3D configuration was used to carry out a 3D resistivity

  18. Tide-driven fluid mud transport in the Ems estuary

    NASA Astrophysics Data System (ADS)

    Becker, Marius; Maushake, Christian; Winter, Christian

    2014-05-01

    The Ems estuary, located at the border between The Netherlands and Germany, experienced a significant change of the hydrodynamic regime during the past decades, as a result of extensive river engineering. With the net sediment transport now being flood-oriented, suspended sediment concentrations have increased dramatically, inducing siltation and formation of fluid mud layers, which, in turn, influence hydraulic flow properties, such as turbulence and the apparent bed roughness. Here, the process-based understanding of fluid mud is essential to model and predict mud accumulation, not only regarding the anthropogenic impact, but also in view of the expected changes of environmental boundary conditions, i.e., sea level rise. In the recent past, substantial progress has been made concerning the understanding of estuarine circulation and influence of tidal asymmetry on upstream sediment accumulation. While associated sediment transport formulations have been implemented in the framework of numerical modelling systems, in-situ data of fluid mud are scarce. This study presents results on tide-driven fluid mud dynamics, measured during four tidal cycles aside the navigation channel in the Ems estuary. Lutoclines, i.e., strong vertical density gradients, were detected by sediment echo sounder (SES). Acoustic Doppler current profiles (ADCP) of different acoustic frequencies were used to determine hydrodynamic parameters and the vertical distribution of suspended sediment concentrations in the upper part of the water column. These continuous profiling measurements were complemented by CTD, ADV, and OBS casts. SES and ADCP profiles show cycles of fluid mud entrainment during accelerating flow, and subsequent settling, and the reformation of a lutocline during decelerating flow and slack water. Significant differences are revealed between flood and ebb phase. Highest entrainment rates are measured at the beginning of the flood phase, associated with strong current shear and

  19. Exploration Depth of Multi-frequency Helicopter EM Systems

    NASA Astrophysics Data System (ADS)

    Yin, C.; Hodges, G.

    2004-05-01

    Due to the high resolution of hilicopter electromagnetic (HEM) systems, they are being widely used for shallow earth resistivity mapping problems. The traditional investigation of the exploration depth of a HEM system is based on the model of a single-frequency coil array over a layered earth. In this paper we extend the study to the multi-frequency HEM systems. We first determine for each frequency channel of a HEM system the maximal depth of a target, beyond which it cannot be identified from the EM signal. This is mathemically realized by assuming that the abnormal signal from the target is three times larger than the noise level of the HEM channel. Since each frequency channel of an HEM system has a different noise level and for different frequency channel the EM field has different penetration depth, we choose the biggest value of these depths as the depth of exploration. Different models are implemented in the study of this paper, including a layered earth model, a dipping plate or a dyke, a 3D ore body, etc. We use as example the Fugro DIGHEM system with three horizontal coplanar (HCP) coils (380 or 900, 7200, 56kHz) and two vertical coaxial (VCX) coils (900, 5500Hz). The following conclusions are obtained: 1. Except for a steeply dipping sheet, the HCP coil array has a larger depth of exploration than the VCX coil array; 2. The depth of exploration may be obtained from different frequency channels for different target geometries and different conductivity contrasts between the target and host rocks. This means that for a specific target geometry and conductivity contrast, we need to search such a frequency channel that offers the maximal value for depth of exploration; 3. Among the factors that influence the depth of exploration, the noise level of the HEM system is the key. The other factors include the geometry of the target and the conductivity contrast between the target and the host rocks, and the relative location between the HEM system and the target

  20. Disciplines and Professors of Astronomy in Undergraduate Physics Teachers Formation Courses in Brazilian Universities. (Spanish Title: Disciplinas y Profesores de Astronomia en los Cursos de Licenciatura en Física en Las Universidades Brasileñas.) Disciplinas e Professores de Astronomia Nos Cursos de Licenciatura em Física das Universidades Brasileiras

    NASA Astrophysics Data System (ADS)

    Roberto, Artur Justiniano, Jr.; Reis, Thiago Henrique; dos Reis Germinaro, Daniel

    2014-12-01

    formación. Aparte de eso, los datos levantados en este trabajo apuntan para un número bajo de afiliados a la SAB (Sociedade Astronômica Brasileira) en los cursos investigados. Se verificó que tener astrónomos en una institución no implica tener una disciplina obligatoria de Astronomía en el curso de licenciatura en Física. Este artigo é o resultado de uma pesquisa sobre a formação básica em Astronomia nos cursos de Licenciatura em Física que fizeram o exame nacional ENADE 2011. O objetivo do trabalho foi identificar se há disciplinas de Astronomia nesses cursos, se ela é obrigatória ou optativa/eletiva, qual a sua carga horária e o período em que é oferecida. Pesquisou-se também a relação entre astrônomos, cursos de Licenciatura em Física e disciplinas de Astronomia. Para realizar essa pesquisa utilizamos os dados do ENADE 2011 e também do censo da Astronomia brasileira. Como resultado, se observa que em apenas 15% dos cursos existe uma disciplina obrigatória de Astronomia e que há uma grande probabilidade de que 85% dos professores de Física formados em 2011 não cursaram nenhuma disciplina de Astronomia durante a graduação. Além disso, os dados levantados nesse trabalho apontam um baixo número de filiados à SAB nos cursos pesquisados. Identifica-se que ter astrônomos na instituição não implica em disciplina obrigatória de Astronomia no curso de Licenciatura em Física.