NCBI nr-aa BLAST: CBRC-MDOM-01-0247 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-MDOM-01-0247 ref|ZP_00545283.1| 60 kDa inner membrane protein [Ehrlichia chaffee...nsis str. Sapulpa] gb|EAM85346.1| 60 kDa inner membrane protein [Ehrlichia chaffeensis str. Sapulpa] ZP_00545283.1 2.1 30% ...

Detection of Ehrlichia spp., Anaplasma spp., Rickettsia spp., and other eubacteria in ticks from the Thai-Myanmar border and Vietnam.

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Parola, Philippe; Cornet, Jean-Paul; Sanogo, Yibayiri Osée; Miller, R Scott; Thien, Huynh Van; Gonzalez, Jean-Paul; Raoult, Didier; Telford III, Sam R; Wongsrichanalai, Chansuda

2003-04-01

A total of 650 ticks, including 13 species from five genera, were collected from animals, from people, or by flagging of the vegetation at sites on the Thai-Myanmar border and in Vietnam. They were tested by PCR to detect DNA of bacteria of the order RICKETTSIALES: Three Anaplasma spp. were detected in ticks collected in Thailand, including (i) Anaplasma sp. strain AnDa465, which was considered a genotype of Anaplasma platys (formerly Ehrlichia platys) and which was obtained from Dermacentor auratus ticks collected from dogs; (ii) Anaplasma sp. strain AnAj360, which was obtained from Amblyomma javanense ticks collected on a pangolin; and (iii) Anaplasma sp. strain AnHl446, which was closely related to Anaplasma bovis and which was detected in Haemaphysalis lagrangei ticks collected from a bear. Three Ehrlichia spp. were identified, including (i) Ehrlichia sp. strain EBm52, which was obtained from Boophilus microplus ticks collected from cattle from Thailand; (ii) Ehrlichia sp. strain EHh324, which was closely related to Ehrlichia chaffeensis and which was detected in Haemaphysalis hystricis ticks collected from wild pigs in Vietnam; and (iii) Ehrlichia sp. strain EHh317, which was closely related to Ehrlichia sp. strain EBm52 and which was also detected in H. hystricis ticks collected from wild pigs in Vietnam. Two Rickettsia spp. were detected in Thailand, including (i) Rickettsia sp. strain RDla420, which was detected in Dermacentor auratus ticks collected from a bear, and (ii) Rickettsia sp. strain RDla440, which was identified from two pools of Dermacentor larvae collected from a wild pig nest. Finally, two bacteria named Eubacterium sp. strain Hw124 and Eubacterium sp. strain Hw191 were identified in Haemaphysalis wellingtoni ticks collected from chicken in Thailand; these strains could belong to a new group of bacteria.

Investigating the Adult Ixodid Tick Populations and Their Associated Anaplasma, Ehrlichia, and Rickettsia Bacteria at a Rocky Mountain Spotted Fever Hotspot in Western Tennessee.

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Trout Fryxell, Rebecca T; Hendricks, Brain M; Pompo, Kimberly; Mays, Sarah E; Paulsen, Dave J; Operario, Darwin J; Houston, Allan E

2017-08-01

Ehrlichiosis and rickettsiosis are two common bacterial tick-borne diseases in the southeastern United States. Ehrlichiosis is caused by ehrlichiae transmitted by Amblyomma americanum and rickettsiosis is caused by rickettsiae transmitted by Amblyomma maculatum and Dermacentor variabilis. These ticks are common and have overlapping distributions in the region. The objective of this study was to identify Anaplasma, Ehrlichia, and Rickettsia species associated with questing ticks in a Rocky Mountain spotted fever (RMSF) hotspot, and identify habitats, time periods, and collection methods for collecting questing-infected ticks. Using vegetation drags and CO 2 -baited traps, ticks were collected six times (May-September 2012) from 100 sites (upland deciduous, bottomland deciduous, grassland, and coniferous habitats) in western Tennessee. Adult collections were screened for Anaplasma and Ehrlichia (simultaneous polymerase chain reaction [PCR]) and Rickettsia using genus-specific PCRs, and resulting positive amplicons were sequenced. Anaplasma and Ehrlichia were only identified within A. americanum (Ehrlichia ewingii, Ehrlichia chaffeensis, Panola Mountain Ehrlichia, and Anaplasma odocoilei sp. nov.); more Ehrlichia-infected A. americanum were collected at the end of June regardless of habitat and collection method. Rickettsia was identified in three tick species; "Candidatus Rickettsia amblyommii" from A. americanum, R. parkeri and R. andeanae from A. maculatum, and R. montanensis ( = montana) from D. variabilis. Overall, significantly more Rickettsia-infected ticks were identified as A. americanum and A. maculatum compared to D. variabilis; more infected-ticks were collected from sites May-July and with dragging. In this study, we report in the Tennessee RMSF hotspot the following: (1) Anaplasma and Ehrlichia are only found in A. americanum, (2) each tick species has its own Rickettsia species, (3) a majority of questing-infected ticks are collected May-July, (4) A

Ehrlichia Meningitis Mimicking Aneurysmal Subarachnoid Hemorrhage: A Case Study for Medical Decision-Making Heuristics.

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Dredla, Brynn; Freeman, William D

2016-04-01

Thunderclap headache is a sudden and severe headache that can occur after an aneurysmal subarachnoid hemorrhage (SAH). Subarachnoid hemorrhage is a medical emergency that requires prompt attention and hospitalization. Patients with thunderclap headache often undergo a noncontrast head computed tomography (CT) scan to ascertain SAH bleeding and, if the scan is negative, then undergo a lumbar puncture to look for cerebrospinal fluid (CSF) red blood cells (RBCs), which would be consistent with an aneurysmal leak. If the initial CT is negative and CSF is positive for RBCs, patients are usually admitted to the hospital for evaluation of intracranial aneurysm. We encountered a patient with thunderclap headache whose initial head CT was negative for SAH and whose CSF tested positive for RBCs. The patient was referred to our center for evaluation and management of aneurysmal SAH. However, on careful review of the patient's medical history, serum laboratory values, and spinal fluid values, the patient was diagnosed with Ehrlichia chaffeensis meningitis. While Ehrlichia meningitis is rare, it is important to recognize the clinical clues that could help avoid formal cerebral angiography, a costly and potentially unnecessary procedure. We present how this case represented a cognitive framing bias and anchoring heuristic as well as steps that medical providers can use to prevent such cognitive errors in diagnosis.

EtpE Binding to DNase X Induces Ehrlichial Entry via CD147 and hnRNP-K Recruitment, Followed by Mobilization of N-WASP and Actin.

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Mohan Kumar, Dipu; Lin, Mingqun; Xiong, Qingming; Webber, Mathew James; Kural, Comert; Rikihisa, Yasuko

2015-11-03

Obligate intracellular bacteria, such as Ehrlichia chaffeensis, perish unless they can enter eukaryotic cells. E. chaffeensis is the etiological agent of human monocytic ehrlichiosis, an emerging infectious disease. To infect cells, Ehrlichia uses the C terminus of the outer membrane invasin entry-triggering protein (EtpE) of Ehrlichia (EtpE-C), which directly binds the mammalian cell surface glycosylphosphatidyl inositol-anchored protein, DNase X. How this binding drives Ehrlichia entry is unknown. Here, using affinity pulldown of host cell lysates with recombinant EtpE-C (rEtpE-C), we identified two new human proteins that interact with EtpE-C: CD147 and heterogeneous nuclear ribonucleoprotein K (hnRNP-K). The interaction of CD147 with rEtpE-C was validated by far-Western blotting and coimmunoprecipitation of native EtpE with endogenous CD147. CD147 was ubiquitous on the cell surface and also present around foci of rEtpE-C-coated-bead entry. Functional neutralization of surface-exposed CD147 with a specific antibody inhibited Ehrlichia internalization and infection but not binding. Downregulation of CD147 by short hairpin RNA (shRNA) impaired E. chaffeensis infection. Functional ablation of cytoplasmic hnRNP-K by a nanoscale intracellular antibody markedly attenuated bacterial entry and infection but not binding. EtpE-C also interacted with neuronal Wiskott-Aldrich syndrome protein (N-WASP), which is activated by hnRNP-K. Wiskostatin, which inhibits N-WASP activation, and cytochalasin D, which inhibits actin polymerization, inhibited Ehrlichia entry. Upon incubation with host cell lysate, EtpE-C but not an EtpE N-terminal fragment stimulated in vitro actin polymerization in an N-WASP- and DNase X-dependent manner. Time-lapse video images revealed N-WASP recruitment at EtpE-C-coated bead entry foci. Thus, EtpE-C binding to DNase X drives Ehrlichia entry by engaging CD147 and hnRNP-K and activating N-WASP-dependent actin polymerization. Ehrlichia chaffeensis, an

A case of human monocytic ehrlichiosis in Serbia

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Arsić Bogdan

2014-01-01

Full Text Available Introduction. Ehrlichiosis is a bacterial zoonosis transmitted by hematophagous arthropods - ticks. In humans, it occurs as monocytic, granulocytic, and ewingii ehrlichiosis. Pathological process is based on parasitic presence of Ehrlichia organisms within peripheral blood cells - monocytes and granulocytes. Case Outline. Fifty-two year old patient was admitted to hospital due to high fever of over 40°C that lasted two days, accompanied with chills, muscle aches, malaise, loss of appetite, headache, confusion, breathing difficulties, and mild dry cough. The history suggested tick bite that occurred seven days before the onset of disease. Doxycycline was introduced and administered for 14 days, causing the disease to subside. Indirect immunofluorescence assay was used to analyze three serum samples obtained from this patient for Ehrlichia chaffeensis antibodies, and peripheral blood smear was evaluated for the presence of Ehrlichia and Ehrlichia aggregation into morulae. Conclusion. Ehrlichiosis should be considered in each case where there is a history of tick bite together with the clinical picture (high fever, chills, muscle aches, headache, generalized weakness and malaise, and possible maculopapular rash. The presence of Ehrlichia chaffeensis antibodies was confirmed in a patient with the history of tick bite, appropriate clinical picture and indirect immunofluorescence assay. This confirmed the presence of human monocytotropic ehrlichiosis, a disease that is uncommonly identified in our country.

Short report: serologic evidence of human ehrlichiosis in Peru.

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Moro, Pedro L; Shah, Jyotsna; Li, Olga; Gilman, Robert H; Harris, Nick; Moro, Manuel H

2009-02-01

A serosurvey for human ehrlichiosis caused by Ehrlichia chaffeensis and Anaplasma phagocytophilum was performed in different regions of Peru by using indirect immunofluorescence assays (IFAs). Regions included an urban community in a shantytown in Lima (Pampas) and three rural communities located on the northern coast of Peru (Cura Mori), in the southern Peruvian Andes (Cochapata), and in the Peruvian jungle region (Santo Tomas). An overall E. chaffeensis seroprevalence of 13% (21 of 160) was found by IFA. Seroprevalences in females and males was 15% (16 of 106) and 9% (5 of 53), respectively. Seroprevalences in Cura Mori, Cochapata, Pampas, and Santo Tomas were 25% (10 of 40), 23% (9 of 40), 3% (1 of 40), and 3% (1 of 40), respectively. Seroprevalences in Cura Mori and Cochapata were significantly higher than in Santo Tomas or Pampas (P Peru. Further studies are needed to characterize Ehrlichia species in Peru, their vectors and their clinical significance.

Efficient high-throughput molecular method to detect Ehrlichia ruminantium in ticks

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Nídia Cangi

2017-11-01

Full Text Available Abstract Background Ehrlichia ruminantium is the causal agent of heartwater, a fatal tropical disease affecting ruminants with important economic impacts. This bacterium is transmitted by Amblyomma ticks and is present in sub-Saharan Africa, islands in the Indian Ocean and the Caribbean, where it represents a threat to the American mainland. Methods An automated DNA extraction method was adapted for Amblyomma ticks and a new qPCR targeting the pCS20 region was developed to improve E. ruminantium screening capacity and diagnosis. The first step in the preparation of tick samples, before extraction, was not automated but was considerably improved by using a Tissue Lyser. The new pCS20 Sol1 qPCR and a previously published pCS20 Cow qPCR were evaluated with the OIE standard pCS20 nested PCR. Results pCS20 Sol1 qPCR was found to be more specific than the nested PCR, with a 5-fold increase in sensitivity (3 copies/reaction vs 15 copies/reaction, was less prone to contamination and less time-consuming. As pCS20 Sol1 qPCR did not detect Rickettsia, Anasplasma and Babesia species or closely related species such as Panola Mountain Ehrlichia, E. chaffeensis and E. canis, its specificity was also better than Cow qPCR. In parallel, a tick 16S qPCR was developed for the quality control of DNA extraction that confirmed the good reproducibility of the automated extraction. The whole method, including the automated DNA extraction and pCS20 Sol1 qPCR, was shown to be sensitive, specific and highly reproducible with the same limit of detection as the combined manual DNA extraction and nested PCR, i.e. 6 copies/reaction. Finally, 96 samples can be tested in one day compared to the four days required for manual DNA extraction and nested PCR. Conclusions The adaptation of an automated DNA extraction using a DNA/RNA viral extraction kit for tick samples and the development of a new qPCR increased the accuracy of E. ruminantium epidemiological studies, as well as the

Novel genotype of Ehrlichia canis detected in samples of human blood bank donors in Costa Rica.

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Bouza-Mora, Laura; Dolz, Gaby; Solórzano-Morales, Antony; Romero-Zuñiga, Juan José; Salazar-Sánchez, Lizbeth; Labruna, Marcelo B; Aguiar, Daniel M

2017-01-01

This study focuses on the detection and identification of DNA and antibodies to Ehrlichia spp. in samples of blood bank donors in Costa Rica using molecular and serological techniques. Presence of Ehrlichia canis was determined in 10 (3.6%) out of 280 blood samples using polymerase chain reaction (PCR) targeting the ehrlichial dsb conserved gene. Analysis of the ehrlichial trp36 polymorphic gene in these 10 samples revealed substantial polymorphism among the E. canis genotypes, including divergent tandem repeat sequences. Nucleotide sequences of dsb and trp36 amplicons revealed a novel genotype of E. canis in blood bank donors from Costa Rica. Indirect immunofluorescence assay (IFA) detected antibodies in 35 (35%) of 100 serum samples evaluated. Thirty samples showed low endpoint titers (64-256) to E. canis, whereas five sera yielded high endpoint titers (1024-8192); these five samples were also E. canis-PCR positive. These findings represent the first report of the presence of E. canis in humans in Central America. Copyright © 2016 Elsevier GmbH. All rights reserved.

Comparative genomics of emerging human ehrlichiosis agents.

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Julie C Dunning Hotopp

2006-02-01

Full Text Available Anaplasma (formerly Ehrlichia phagocytophilum, Ehrlichia chaffeensis, and Neorickettsia (formerly Ehrlichia sennetsu are intracellular vector-borne pathogens that cause human ehrlichiosis, an emerging infectious disease. We present the complete genome sequences of these organisms along with comparisons to other organisms in the Rickettsiales order. Ehrlichia spp. and Anaplasma spp. display a unique large expansion of immunodominant outer membrane proteins facilitating antigenic variation. All Rickettsiales have a diminished ability to synthesize amino acids compared to their closest free-living relatives. Unlike members of the Rickettsiaceae family, these pathogenic Anaplasmataceae are capable of making all major vitamins, cofactors, and nucleotides, which could confer a beneficial role in the invertebrate vector or the vertebrate host. Further analysis identified proteins potentially involved in vacuole confinement of the Anaplasmataceae, a life cycle involving a hematophagous vector, vertebrate pathogenesis, human pathogenesis, and lack of transovarial transmission. These discoveries provide significant insights into the biology of these obligate intracellular pathogens.

Serologic Evidence of Human Monocytic and Granulocytic Ehrlichiosis in Israel

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Keysary, Avi; Amram, Lili; Keren, Gershon; Sthoeger, Zev; Potasman, Israel; Jacob, Amir; Strenger, Carmella; Dawson, Jacqueline E.

1999-01-01

We conducted a retrospective serosurvey of 1,000 persons in Israel who had fever of undetermined cause to look for Ehrlichia chaffeensis antibodies. Four of five cases with antibodies reactive to E. chaffeensis were diagnosed in the summer, when ticks are more active. All patients had influenzalike symptoms with high fever. None of the cases was fatal. Three serum samples were also seroreactive for antibodies to E. canis, and one was also reactive to the human granulocytic ehrlichiosis (HGE) agent. The titer to the HGE agent in this patient was higher than the serum titer to E. chaffeensis, and the Western blot analysis also indicated that the HGE agent was the primary cause of infection. We present the first serologic evidence that the agents of human monocytic ehrlichiosis (HME) and HGE are present in Israel. Therefore, human ehrlichiosis should be included in the differential diagnoses for persons in Israel who have been exposed to ticks and have influenzalike symptoms. PMID:10603210

An Ehrlichia strain from a llama (Lama glama) and Llama-associated ticks (Ixodes pacificus).

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Barlough, J E; Madigan, J E; Turoff, D R; Clover, J R; Shelly, S M; Dumler, J S

1997-01-01

An ehrlichia was identified in the blood of a diseased llama (lama glama). Sequencing of its 16S rRNA gene showed the ehrlichia to be closely related to members of the Ehrlichia phagocytophila genogroup. The agent was also found in a pool of ticks (Ixodes pacificus) collected at the llama site. PMID:9157118

Seroprevalencia de Leptospira sp., Rickettsia sp. Ehrlichia sp. en trabajadores rurales del departamento de Sucre, Colombia Seroprevalence of Leptospira sp., Rickettsia sp. and Ehrlichia sp. in rural workers of Sucre, Colombia

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Rodrigo Ríos

2008-06-01

Full Text Available Objective. Determinar la seroprevalencia de Leptospira sp., Rickettsia sp. y Ehrlichia sp. en trabajadores de áreas rurales del departamento de Sucre. Material y métodos. Se realizó un estudio escriptivo, prospectivo, de corte transversal, que pretendió determinar la seroprevalencia e Leptospira sp., Rickettsia sp. y Ehrlichia sp. en 90 trabajadores de áreas rurales del departamento de Sucre. Se estableció la presencia de anticuerpos séricos anti-IgM específicos anti-Leptospira por la técnica de ELISA indirecta. Para la determinación de Rickettsia sp. y Ehrlichia sp. se uso la técnica de inmunofluorescencia indirecta. Resultados. La población evaluada estaba compuesta por 27 (30% ordeñadores, 21 (23% jornaleros, 18 (20% profesionales del campo y 24 (27% que realizaban otras actividades. Ventidós (24% muestras resultaron positivas en alguna de las pruebas. De éstas, 12 (13,3% fueron positivas para Leptospira sp., 7 (7,8% para Rickettsia sp. y 3 (3,3% ara Ehrlichia sp. Conclusión. Este fue el primer estudio que se llevó a cabo en el departamento de Sucre y permitió demostrar que existe una prevalencia importante de Leptospira p.,Rickettsia sp. y Ehrlichia sp.. Los factores de riesgo ocupacional fueron factores determinantes en la seropositividad.Objective. To determine the seroprevalence of Leptospira sp., Rickettsia sp. and Ehrlichia sp. in agricultural workers of Sucre. Methods. A descriptive prospective cross-sectional study was conducted in ninety rural workers of Sucre. Presence of serum antibodies anti-IgM specific anti-Leptospira by indirect ELISA was established. For the determination of Rickettsia and Ehrlichia indirect inmunoflorescence was used. Results.The population was composed by 27 (30% milkers, 21 (23% day workers, 18 farm professionals (20% and 24 (26% workers in others activities. A total of 22 (24% samples were positive to some test. Twelve (13.3% were positive to Leptospira sp., seven (7.8% to Rickettsia sp

The Microbiome of Ehrlichia-Infected and Uninfected Lone Star Ticks (Amblyomma americanum.

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R T Trout Fryxell

Full Text Available The Lone Star tick, Amblyomma americanum, transmits several bacterial pathogens including species of Anaplasma and Ehrlichia. Amblyomma americanum also hosts a number of non-pathogenic bacterial endosymbionts. Recent studies of other arthropod and insect vectors have documented that commensal microflora can influence transmission of vector-borne pathogens; however, little is known about tick microbiomes and their possible influence on tick-borne diseases. Our objective was to compare bacterial communities associated with A. americanum, comparing Anaplasma/Ehrlichia -infected and uninfected ticks. Field-collected questing specimens (n = 50 were used in the analyses, of which 17 were identified as Anaplasma/Ehrlichia infected based on PCR amplification and sequencing of groEL genes. Bacterial communities from each specimen were characterized using Illumina sequencing of 16S rRNA gene amplicon libraries. There was a broad range in diversity between samples, with inverse Simpson's Diversity indices ranging from 1.28-89.5. There were no statistical differences in the overall microbial community structure between PCR diagnosed Anaplasma/Ehrlichia-positive and negative ticks, but there were differences based on collection method (P < 0.05, collection site (P < 0.05, and sex (P < 0.1 suggesting that environmental factors may structure A. americanum microbiomes. Interestingly, there was not always agreement between Illumina sequencing and PCR diagnostics: Ehrlichia was identified in 16S rRNA gene libraries from three PCR-negative specimens; conversely, Ehrlichia was not found in libraries of six PCR-positive ticks. Illumina sequencing also helped identify co-infections, for example, one specimen had both Ehrlichia and Anaplasma. Other taxa of interest in these specimens included Coxiella, Borrelia, and Rickettsia. Identification of bacterial community differences between specimens of a single tick species from a single geographical site indicates that

Associated Factors to Seroprevalence of Ehrlichia spp. in Dogs of Quintana Roo, Mexico

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Pedro Pablo Martínez-Vega

2016-01-01

Full Text Available The objective of this study was to determine the seroprevalence to Ehrlichia spp. in dogs from Xcalak, Quintana Roo, Mexico, and the associated factors. Serum samples were obtained from 118 dogs and used in an indirect immunofluorescent assay test for the detection of antibodies against Ehrlichia spp. A questionnaire was used to obtain information about possible variables associated with seroprevalence. These variables were analyzed through Chi2 test and logistic regression. Dog seroprevalence of antibodies against Ehrlichia spp. was 64% (75/118. Fifty-two percent (61/118 of dogs had tick infestation which was identified as Rhipicephalus sanguineus sensu lato. Anemia was observed in 36% of dogs. Leucopenia (2.5%, thrombocytopenia (70%, and hemorrhage (14% were also observed. Thirty-one percent (23/75 of dogs with anemia, 4% (3/75 of dogs with leucopenia, 80% (60/75 of dogs with thrombocytopenia, 17% (13/75 of dogs with hemorrhages, and 59% (44/75 of dogs with ticks were positive for Ehrlichia spp. antibodies. The factors associated with seroprevalence were age (1–3 and >3 years old, OR = 7.77 and OR = 15.39, resp., tick infestation (OR = 3.13, and thrombocytopenia (OR = 3.36. In conclusion, seroprevalence of Ehrlichia spp. was high in the community of Xcalak and its associated factors were age, tick infestation, and thrombocytopenia.

Associated Factors to Seroprevalence of Ehrlichia spp. in Dogs of Quintana Roo, Mexico.

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Martínez-Vega, Pedro Pablo; Bolio-Gonzalez, Manuel Emilio; Rodríguez-Vivas, Roger Iván; Gutierrez-Blanco, Eduardo; Pérez-Osorio, Carlos; Villegas-Perez, Sandra Luz; Sauri-Arceo, Carlos Humberto

2016-01-01

The objective of this study was to determine the seroprevalence to Ehrlichia spp. in dogs from Xcalak, Quintana Roo, Mexico, and the associated factors. Serum samples were obtained from 118 dogs and used in an indirect immunofluorescent assay test for the detection of antibodies against Ehrlichia spp. A questionnaire was used to obtain information about possible variables associated with seroprevalence. These variables were analyzed through Chi 2 test and logistic regression. Dog seroprevalence of antibodies against Ehrlichia spp. was 64% (75/118). Fifty-two percent (61/118) of dogs had tick infestation which was identified as Rhipicephalus sanguineus sensu lato . Anemia was observed in 36% of dogs. Leucopenia (2.5%), thrombocytopenia (70%), and hemorrhage (14%) were also observed. Thirty-one percent (23/75) of dogs with anemia, 4% (3/75) of dogs with leucopenia, 80% (60/75) of dogs with thrombocytopenia, 17% (13/75) of dogs with hemorrhages, and 59% (44/75) of dogs with ticks were positive for Ehrlichia spp. antibodies. The factors associated with seroprevalence were age (1-3 and >3 years old, OR = 7.77 and OR = 15.39, resp.), tick infestation (OR = 3.13), and thrombocytopenia (OR = 3.36). In conclusion, seroprevalence of Ehrlichia spp. was high in the community of Xcalak and its associated factors were age, tick infestation, and thrombocytopenia.

The glycoprotein TRP36 of Ehrlichia sp. UFMG-EV and related cattle pathogen Ehrlichia sp. UFMT-BV evolved from a highly variable clade of E. canis under adaptive diversifying selection

Czech Academy of Sciences Publication Activity Database

Cabezas-Cruz, A.; Valdés, James J.; de la Fuente, J.

2014-01-01

Roč. 7, DEC 10 2014 (2014), s. 584 ISSN 1756-3305 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Ehrlichia sp. UFMG-EV * Ehrlichia sp. UFMT-BV * E. mineirensis * Host-shift * Diversifying episodic selection Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.430, year: 2014

Anaplasma, Ehrlichia and Rickettsia species infections in cats

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Pennisi, Maria Grazia; Hofmann-Lehmann, Regina; Radford, Alan D; Tasker, Séverine; Belák, Sándor; Addie, Diane D; Boucraut-Baralon, Corine; Egberink, Herman; Frymus, Tadeusz; Gruffydd-Jones, Tim; Hartmann, Katrin; Horzinek, Marian C; Hosie, Margaret J; Lloret, Albert; Lutz, Hans; Marsilio, Fulvio; Thiry, Etienne; Truyen, Uwe; Möstl, Karin

2017-01-01

OVERVIEW: Anaplasma species, Ehrlichia species and Rickettsia species are vector-borne pathogens infecting a wide variety of mammals, but causing disease in very few of them. Infection in cats: Anaplasma phagocytophilum is the most important feline pathogen among these rickettsial organisms, and

Seroprevalence of Ehrlichia canis infection in stray dogs from Serbia

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Nataša Bogićević

2017-03-01

Full Text Available Canine Monocytic Ehrlichiosis is a zoonotic bacterial disease with worldwide distribution. With regards to the population of stray dogs, the disease is facilitated due to their lifestyle and the lack of anti-parasitic protection. The aim of this study was to provide serological data on the presence of a specific Ehrlichia canis IgG antibodies in stray dogs, originating from 7 municipalities in Serbia. During the period from April 2013 to June 2014, 217 canine sera were submitted to the laboratory of the Department of Infectious Diseases of Animals and Bees, Faculty of Veterinary Medicine in Belgrade. An immunofluorescent antibody test (IFAT was performed to detect antibodies to Ehrlichia canis (cut off, 1:50. Seropositive dogs were found in 5 out of 7 counties with a seroprevalence varying from 3.57% to 20% and an overall seroprevalence of 11.06% (24/217. There was no statistically significant difference between the prevalence of infection and the host age or gender. Results showed that stray dogs contribute to maintaining and spreading of Ehrlichia canis in Serbia. Due to the close relationship between people and dogs, it is of great importance to constantly monitor and improve prevention of this disease.

Lymph node hemophagocytosis in rickettsial diseases: a pathogenetic role for CD8 T lymphocytes in human monocytic ehrlichiosis (HME?

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Dumler J Stephen

2006-07-01

Full Text Available Abstract Background Human monocytic ehrlichiosis (HME and Rocky Mountain spotted fever (RMSF are caused by Ehrlichia chaffeensis and Rickettsia rickettsii, respectively. The pathogenesis of RMSF relates to rickettsia-mediated vascular injury, but it is unclear in HME. Methods To study histopathologic responses in the lymphatic system for correlates of immune injury, lymph nodes from patients with HME (n = 6 and RMSF (n = 5 were examined. H&E-stained lymph node tissues were examined for five histopathologic features, including hemophagocytosis, cellularity, necrosis, and vascular congestion and edema. The relative proportions of CD68 macrophages, CD8 and CD4 T lymphocytes, and CD20 B lymphocytes were evaluated by immunohistochemical staining. Results Hemophagocytosis was similar in HME and RMSF, and was greater than in control cases (p = .015. Cellularity in HME was not different from controls, whereas RMSF lymph nodes were markedly less cellular (p E. chaffeensis-infected mononuclear phagocytes were infrequent compared to R. rickettsii-infected endothelial cells. More CD8 cells in lymph nodes were observed with HME (p Conclusion Hemophagocytosis, CD8 T cell expansion, and the paucity of infected cells in HME, suggest that E. chaffeensis infection leads to macrophage activation and immune-mediated injury.

Natural history of zoonotic Ehrlichia species in the United States and discovery of a novel ehrlichial pathogen

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Loftis, A.D.

2008-01-01

Ehrlichia are obligate intracellular pathogens, transmitted by ixodid ticks, of both animals and humans. Ehrlichiae are emerging diseases in the USA, and the discovery of new species proceeds more rapidly than the development of models to study these agents. Laboratory animals were evaluated as

Detection and phylogenetic characterisation of novel Anaplasma and Ehrlichia species in Amblyomma triguttatum subsp. from four allopatric populations in Australia.

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Gofton, Alexander W; Waudby, Helen P; Petit, Sophie; Greay, Telleasha L; Ryan, Una M; Irwin, Peter J

2017-08-01

Anaplasma and Ehrlichia spp. are tick-borne pathogens that can cause severe disease in domestic animals, and several species are responsible for emerging zoonoses in the northern hemisphere. Until recently, the only members of these genera reported in Australia (A. marginale, A. centrale, and A. platys) were introduced from other continents, through the importation of domestic animals and their associated ticks. However, unique Anaplasma and Ehrlichia 16S rRNA gene sequences were recently detected for the first time in native Australian ticks, particularly in Amblyomma triguttatum subsp. ticks from southwest Western Australia (WA). We used molecular techniques to survey Am. triguttatum subsp. ticks from four allopatric populations in southern and western Australia for Anaplasma and Ehrlichia species, and described here the phylogeny of these novel organisms. An A. bovis variant (genotype Y11) was detected in ticks from two study sites; Yanchep National Park (12/280, 4.3%) and Barrow Island (1/69, 1.4%). Phylogenetic analysis of 16S rRNA and groEL gene sequences concluded that A. bovis genotype Y11 is a unique genetic variant, distinct from other A. bovis isolates worldwide. Additionally, a novel Ehrlichia species was detected in Am. triguttatum subsp. from three of the four study sites; Yanchep National Park (18/280, 6.4%), Bungendore Park (8/46, 17.4%), and Innes National Park (9/214, 4.2%), but not from Barrow Island. Phylogenetic analysis of 16S, groEL, gltA, and map1 gene sequences revealed that this Ehrlichia sp. is most closely related to, but clearly distinct from, E. ruminantium and Ehrlichia sp. Panola Mountain. We propose to designate this new species 'Candidatus Ehrlichia occidentalis'. Anaplasma bovis genotype Y11 and 'Candidatus E. occidentalis' are the first Anaplasma and Ehrlichia species to be recorded in native Australian ticks. Copyright © 2017 Elsevier GmbH. All rights reserved.

The genome of obligately intracellular Ehrlichia canis revealsthemes of complex membrane structure and immune evasion strategies

Energy Technology Data Exchange (ETDEWEB)

Mavromatis, K.; Kuyler Doyle, C.; Lykidis, A.; Ivanova, N.; Francino, P.; Chain, P.; Shin, M.; Malfatti, S.; Larimer, F.; Copeland,A.; Detter, J.C.; Land, M.; Richardson, P.M.; Yu, X.J.; Walker, D.H.; McBride, J.W.; Kyrpides, N.C.

2005-09-01

Ehrlichia canis, a small obligately intracellular, tick-transmitted, gram-negative, a-proteobacterium is the primary etiologic agent of globally distributed canine monocytic ehrlichiosis. Complete genome sequencing revealed that the E. canis genome consists of a single circular chromosome of 1,315,030 bp predicted to encode 925 proteins, 40 stable RNA species, and 17 putative pseudogenes, and a substantial proportion of non-coding sequence (27 percent). Interesting genome features include a large set of proteins with transmembrane helices and/or signal sequences, and a unique serine-threonine bias associated with the potential for O-glycosylation that was prominent in proteins associated with pathogen-host interactions. Furthermore, two paralogous protein families associated with immune evasion were identified, one of which contains poly G:C tracts, suggesting that they may play a role in phase variation and facilitation of persistent infections. Proteins associated with pathogen-host interactions were identified including a small group of proteins (12) with tandem repeats and another with eukaryotic-like ankyrin domains (7).

A molecular epidemiological survey of Babesia, Hepatozoon, Ehrlichia and Anaplasma infections of dogs in Japan

Science.gov (United States)

KUBO, Shotaro; TATENO, Morihiro; ICHIKAWA, Yasuaki; ENDO, Yasuyuki

2015-01-01

Tick-borne diseases are often encountered in canine clinical practice. In the present study, a molecular epidemiological survey of dogs in Japan was conducted to understand the prevalence and geographical distribution of Babesia spp., Hepatozoon spp., Ehrlichia spp. and Anaplasma spp. Pathogen-derived DNA in blood samples obtained from 722 dogs with a history of exposure to ticks and/or fleas was examined by PCR. The prevalence of Babesia gibsoni, Babesia odocoilei-like species, Hepatozoon canis and Ehrlichia spp./Anaplasma spp. was 2.4% (16/722), 0.1% (1/722), 2.5% (18/722) and 1.5% (11/722), respectively. While B. gibsoni and Ehrlichia spp./Anaplasma spp. were detected in the western part of Japan, H. canis was detected in Tohoku area in addition to western and central parts of Japan. PMID:25947226

Leishmania, Babesia and Ehrlichia in urban pet dogs: co-infection or cross-reaction in serological methods?

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Felipe da Silva Krawczak

2015-02-01

Full Text Available INTRODUCTION: The present study was designed to assess the occurrence of co-infection or cross-reaction in the serological techniques used for detecting the anti-Leishmania spp., -Babesia canis vogeli and -Ehrlichia canis antibodies in urban dogs from an area endemic to these parasites. METHODS: The serum samples from dogs were tested for the Babesia canis vogeli strain Belo Horizonte antigen and Ehrlichia canis strain São Paulo by immunofluorescence antibody test (IFAT and by anti-Leishmania immunoglobulin G (IgG antibody detection to assess Leishmania infection. We used the following four commercial kits for canine visceral leishmaniasis: ELISA, IFAT, Dual Path Platform (DPP (Bio Manguinhos(r/FIOCRUZ/MS and a rK39 RDT (Kalazar Detect Canine Rapid Test; Inbios. RESULTS : Of 96 serum samples submitted to serological assays, 4 (4.2% were positive for Leishmania as determined by ELISA; 12 (12.5%, by IFAT; 14 (14.6% by rK39 RDT; and 20 (20.8%, by DPP. Antibodies against Ehrlichia and Babesia were detected in 23/96 (23.9% and 30/96 (31.2% samples, respectively. No significant association was identified between the results of tests for detecting Babesia or Ehrlichia and those for detecting Leishmania (p-value>0.05. CONCLUSIONS: In the present study, we demonstrated co-infection with Ehrlichia or Babesia and Leishmania in dogs from Minas Gerais (Brazil; we also found that the serological tests that were used did not cross-react.

Detection of Ehrlichia canis in domestic cats in the central-western region of Brazil

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Ísis Assis Braga

2014-06-01

Full Text Available Ehrlichiosis is a worldwide distributed disease caused by different bacteria of the Ehrlichia genus that are transmitted by arthropod vectors. Its occurrence in dogs is considered endemic in several regions of Brazil. Regarding cats, however, few studies have been done and, consequently, there is not enough data available. In order to detect Ehrlichia spp. in cats from the central-western region of Brazil, blood and serum samples were collected from a regional population of 212 individuals originated from the cities of Cuiabá and Várzea Grande. These animals were tested by the Immunofluorescence Assay (IFA and the Polymerase Chain Reaction (PCR designed to amplify a 409 bp fragment of the dsb gene. The results obtained show that 88 (41.5% cats were seropositive by IFA and 20 (9.4% cats were positive by PCR. The partial DNA sequence obtained from PCR products yielded twenty samples that were found to match perfectly the Ehrlichia canis sequences deposited on GenBank. The natural transmission of Ehrlichia in cats has not been fully established. Furthermore, tick infestation was not observed in the evaluated cats and was not observed any association between age, gender and positivity of cats in both tests. The present study reports the first serological and molecular detection of E. canis in domestic cats located in the endemic area previously mentioned.

NNDSS - Table II. Ehrlichiosis and Anaplasmosis, Ehrlichia ewingii infection to Undetermined

Data.gov (United States)

U.S. Department of Health & Human Services — NNDSS - Table II. Ehrlichiosis and Anaplasmosis, Ehrlichia ewingii infection to Undetermined - 2018. In this Table, provisional cases of selected notifiable diseases...

Factores asociados a la infección por Ehrlichia canis en perros infestados con garrapatas en la ciudad de Huánuco, Perú

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Edward Huerto-Medina

Full Text Available El objetivo del estudio fue determinar la frecuencia y factores asociados a la infección por Ehrlichia canis en perros. Se recolectaron muestras de sangre de 150 perros infestados con garrapatas en 10 consultorios veterinarios de la ciudad de Huánuco en Perú, los perros fueron seleccionados al azar sin distinción de raza, edad ni sexo. Se detectó anticuerpos contra Ehrlichia canis mediante inmunoensayo cromatográfico. El 51,3% de perros estuvieron infectados por Ehrlichia canis. En el análisis multivariado se encontraron asociados a la presencia Ehrlichia canis, el mal estado de salud del perro (p=0,049, un promedio mayor de infestación por garrapatas (p=0,018, perros de edad adulta (p=0,038. La frecuencia de Ehrlichia canis en perros de esta ciudad es alta. Se recomienda el control de la garrapata marrón del perro (Rhipicephalus sanguineus vector de la Ehrlichia canis

Dicty_cDB: Contig-U14355-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available lkiii*iwl *ly*iiivk*ipmklipliqkvihhyimpyslnvlikfsciy*ikrkyvlenviwmvihh fiisvknsnhqnvre*fkp*lkkvqiltnkiim...AQ046505 ) RPCI11-42E14.TJ RPCI-11 Homo sapiens genomic clon... 46 1.5 1 ( EJ349319 ) 1092963571972 Global-Ocean-Sampli...655( CP000236 |pid:none) Ehrlichia chaffeensis str. Arkan... 46 0.001 DQ058898_1( DQ058898 |pid:none) Nasutitermes graveolus reli...041156664 Global-Ocean-Sampling_GS-34-01-01-1... 48 0.37 1 ( EJ247332 ) 1095337027578 Global-Ocean-Sampling_...ry Neovison vison ... 46 1.5 1 ( ER388657 ) 1094428746559 Global-Ocean-Sampling_GS-34-01-01-1... 46 1.5 1 (

Molecular epidemiology of heartwater (Ehrlichia ruminantium infection) in The Gambia

NARCIS (Netherlands)

Faburay, B.

2007-01-01

Heartwater is caused by Ehrlichia ruminantium and transmitted by ticks of the genus Amblyomma. It occurs in sub-Saharan Africa and in the Caribbean and affects domestic ruminants. There is general lack of information on the epidemiology of the disease in The Gambia. Results of a countrywide

Molecular Characterization and Phylogenetic Analysis of Anaplasma spp. and Ehrlichia spp. Isolated from Various Ticks in Southeastern and Northwestern Regions of Iran.

Science.gov (United States)

Jafar Bekloo, Ahmad; Ramzgouyan, Maryam Roya; Shirian, Sadegh; Faghihi, Faezeh; Bakhshi, Hassan; Naseri, Fatemeh; Sedaghat, Mehdi; Telmadarraiy, Zakkyeh

2018-05-01

Anaplasma/Ehrlichia species are tick-transmitted pathogens that cause infections in humans and numerous domestic and wild animal species. There is no information available on the molecular characteristics and phylogenetic position of Anaplasma/Ehrlichia spp. isolated from tick species from different geographic locations in Iran. The aim of this study was to determine the prevalence, molecular characteristics, and phylogenetic relationship of both Anaplasma spp. and Ehrlichia spp. in tick species isolated from different domestic animals from two different geographical locations of Iran. A total of 930 ticks were collected from 93 cattle, 250 sheep, and 587 goats inhabiting the study areas. The collected ticks were then investigated for the presence of Anaplasma/Ehrlichia spp. using nested PCR based on the 16S rRNA gene, followed by sequencing. Sequence analysis was done based on the data published in the GenBank on Anaplasma/Ehrlichia spp. isolates using bioinformatic tools such as the standard nucleotide BLAST. Genome of Anaplasma or Ehrlichia spp. was detected in 14 ticks collected in Heris, including 5 Dermacentor marginatus, 1 Haemaphysalis erinacei, 3 Hyalomma anatolicum, and 4 Rhipicephalus sanguineus, also in 29 ticks collected in Chabahar, including 14 R. sanguineus, 8 D. marginatus, 3 Hyalomma Anatolicum, and 4 Hyalomma dromedarii. Partial analysis of the 16S rRNA gene sequence of positive samples collected from goats and sheep showed that they were infected with Anaplasma/Ehrlichia spp. that were 94-98% identical to ovine Anaplasma and 91-96% identical to Neoehrlichia and Ehrlichia spp. The various ticks identified in this study suggest the possible emergence of tick-borne diseases in animals and humans in these regions. R. sanguineus and D. marginatus seem to be predominant vectors responsible for anaplasmosis in these regions. Partial sequence analysis of the 16S rRNA gene showed that A. ovis is genetically polymorphic in these regions. Furthermore, an

High infection of Anaplasma and Ehrlichia spp. among tick species collected from different geographical locations of Iran

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Leila Tajedin

2016-10-01

Full Text Available Objective: To ascertain the prevalence of the Anaplasma/Ehrlichia infections in tick population within four provinces of Iran. Methods: A total of 384 tick specimens were collected from domestic animals inhabiting in four provinces (East Azerbaijan, Gilan, South Khorasan and Yazd. Specimens were identified based on morphological analysis. The detection of Anaplasma spp./Ehrlichia spp. within tick samples was carried out by nested PCR amplification of the 16S ribosomal RNA gene accompanied by DNA sequencing and analysis for verification. Results: A total of 10 tick species were identified as follows: Ornithodoros lahorensis (O. lahorensis (44.8%, Hyalomma dromedarii (15.6%, Dermacentor marginatus (13.5%, Hyalomma anatolicum (11.2%, Hyalomma asiaticum (5.7%, Hyalomma marginatum (4.9%, Rhipicephalus sanguineus (2.3%, Hyalomma detritum (1.0%, Dermacentor niveus (0.5% and Argas persicus (0.3%. The percentage distribution of Anaplasma/Ehrlichia was 55.5% (213 across 384 studied ticks. Conclusions: To the best of our knowledge, this is the first report of Anaplasma ovis infection in O. lahorensis in Iran. We also conjecture the prevalence of Ehrlichia spp. in Yazd Province based on sequencing results; also, it is suggested that O. lahorensis is a potential vector in the studied area. This survey highlights the importance of Argasidae family to verify and correlate their threat in causing anaplasmosis and other diseases in animals.

Ticks circulate Anaplasma, Ehrlichia, Babesia and Theileria parasites in North of Iran.

Science.gov (United States)

Bekloo, Ahmad Jafar; Bakhshi, Hasan; Soufizadeh, Ayoub; Sedaghat, Mohammad Mehdi; Bekloo, Romina Jafar; Ramzgouyan, Maryam Roya; Chegeni, Asadollah Hosseini; Faghihi, Faezeh; Telmadarraiy, Zakkyeh

2017-12-15

Ticks serve as important vectors of some pathogens of medical importance all over the world and identification of their rate of infection plays an important role for further control of diseases. In the current study, we investigated on ticks collected from north of Iran where raising and caring livestock are the main task of the people in order to find evidences of infection of Babesia, Theileria, Anaplasma and Ehrlichia microbial agents. Totally, 609 hard tick species from two genera Hyalomma and Rhipicephalus including; Hy. scupense, Hy. dromedarii, Hy. rufipes, Hy. marginatum, Hy. asiaticum, Hy. anatolicum, R. bursa, R. sanguineus and R. turanicus were identified. Molecular analysis revealed the presence of Anaplasma, Ehrlichia, Babesia and Theileria microorganism agents in all collected tick species except Hy. asiaticum and R. turanicus. To the best of our knowledge, this is the first report on identification of B. occultans in Hyalomma anatolicum and B. ovis in Hyalomma sp in Iran. Copyright © 2017 Elsevier B.V. All rights reserved.

Do Tick Attachment Times Vary between Different Tick-Pathogen Systems?

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Stephanie L. Richards

2017-05-01

Full Text Available Improvements to risk assessments are needed to enhance our understanding of tick-borne disease epidemiology. We review tick vectors and duration of tick attachment required for pathogen transmission for the following pathogens/toxins and diseases: (1 Anaplasma phagocytophilum (anaplasmosis; (2 Babesia microti (babesiosis; (3 Borrelia burgdorferi (Lyme disease; (4 Southern tick-associated rash illness; (5 Borrelia hermsii (tick-borne relapsing fever; (6 Borrelia parkeri (tick-borne relapsing fever; (7 Borrelia turicatae (tick-borne relapsing fever; (8 Borrelia mayonii; (9 Borrelia miyamotoi; (10 Coxiella burnetii (Query fever; (11 Ehrlichia chaffeensis (ehrlichiosis; (12 Ehrlichia ewingii (ehrlichiosis; (13 Ehrlichia muris; (14 Francisella tularensis (tularemia; (15 Rickettsia 364D; (16 Rickettsia montanensis; (17 Rickettsia parkeri (American boutonneuse fever, American tick bite fever; (18 Rickettsia ricketsii (Rocky Mountain spotted fever; (19 Colorado tick fever virus (Colorado tick fever; (20 Heartland virus; (21 Powassan virus (Powassan disease; (22 tick paralysis neurotoxin; and (23 Galactose-α-1,3-galactose (Mammalian Meat Allergy-alpha-gal syndrome. Published studies for 12 of the 23 pathogens/diseases showed tick attachment times. Reported tick attachment times varied (<1 h to seven days between pathogen/toxin type and tick vector. Not all studies were designed to detect the duration of attachment required for transmission. Knowledge of this important aspect of vector competence is lacking and impairs risk assessment for some tick-borne pathogens.

Bacteria of the genera Ehrlichia and Rickettsia in ticks of the family Ixodidae with medical importance in Argentina.

Science.gov (United States)

Sebastian, Patrick S; Tarragona, Evelina L; Bottero, María N Saracho; Mangold, Atilio J; Mackenstedt, Ute; Nava, Santiago

2017-01-01

The aim of this study was to get an overview about the occurrence of bacteria from the genus Ehrlichia and Rickettsia in ixodid ticks with medical importance in Argentina. Therefore, in 2013 and 2014, free-living ticks were collected in different provinces of northern Argentina. These ticks were determined as Amblyomma sculptum, Amblyomma neumanni, Amblyomma parvum, Amblyomma triste, Amblyomma ovale, Amblyomma tonelliae and Haemaphysalis juxtakochi. All samples were tested to determine the infection with Ehrlichia spp. and Rickettsia spp. by PCR assays. Rickettsial DNA was detected in all tested tick species, with the exception of A. tonelliae. 'Candidatus Rickettsia amblyommii', 'Candidatus Rickettsia andeanae', and Rickettsia parkeri were found in A. neumanni, A. parvum, and A. triste, respectively. Another rickettsial species, Rickettsia bellii, was found in A. sculptum, A. ovale and H. juxtakochi. None of the tested ticks showed infection with Ehrlichia. The results of the study demonstrate that Rickettsia species belonging to the spotted fever group are associated with various species of Amblyomma throughout a wide area of northern Argentina, where cases of Amblyomma ticks biting humans are common.

In vitro Culture of a Novel Genotype of Ehrlichia sp from Brazil

Czech Academy of Sciences Publication Activity Database

Zweygarth, E.; Schol, H.; Lis, K.; Cabezas Cruz, Alejandro; Thiel, C.; Silaghi, C.; Ribeiro, M.F.B.; Passos, L.M.F.

2013-01-01

Roč. 60, NOV 2013 (2013), s. 86-92 ISSN 1865-1674 Grant - others:EU(XE) FP7-PEOPLE-ITN No.238511 Institutional support: RVO:60077344 Keywords : Ehrlichia * Rhipicephalus (Boophilus) microplus * in vitro culture * tick cell * DH82 * endothelial cell * cattle * 16S rRNA * Brazil Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.116, year: 2013

Iron Starvation Conditions Upregulate Ehrlichia ruminantium Type IV Secretion System, tr1 Transcription Factor and map1 Genes Family through the Master Regulatory Protein ErxR

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Amal Moumène

2018-01-01

Full Text Available Ehrlichia ruminantium is an obligatory intracellular bacterium that causes heartwater, a fatal disease in ruminants. Due to its intracellular nature, E. ruminantium requires a set of specific virulence factors, such as the type IV secretion system (T4SS, and outer membrane proteins (Map proteins in order to avoid and subvert the host's immune response. Several studies have been conducted to understand the regulation of the T4SS or outer membrane proteins, in Ehrlichia, but no integrated approach has been used to understand the regulation of Ehrlichia pathogenicity determinants in response to environmental cues. Iron is known to be a key nutrient for bacterial growth both in the environment and within hosts. In this study, we experimentally demonstrated the regulation of virB, map1, and tr1 genes by the newly identified master regulator ErxR (for Ehrlichia ruminantium expression regulator. We also analyzed the effect of iron depletion on the expression of erxR gene, tr1 transcription factor, T4SS and map1 genes clusters in E. ruminantium. We show that exposure of E. ruminantium to iron starvation induces erxR and subsequently tr1, virB, and map1 genes. Our results reveal tight co-regulation of T4SS and map1 genes via the ErxR regulatory protein at the transcriptional level, and, for the first time link map genes to the virulence function sensu stricto, thereby advancing our understanding of Ehrlichia's infection process. These results suggest that Ehrlichia is able to sense changes in iron concentrations in the environment and to regulate the expression of virulence factors accordingly.

Novel Ehrlichia and Hepatozoon agents infecting the crab-eating fox (Cerdocyon thous) in southeastern Brazil.

Science.gov (United States)

Almeida, Aliny P; Souza, Tayse D; Marcili, Arlei; Labruna, Marcelo B

2013-05-01

This study evaluated infection by vector-borne agents in 58 crab-eating fox (Cerdocyon thous L.) that were road-killed in an Atlantic rainforest reserve in the state of Espírito Santo, southeastern Brazil. Spleen, lung, or blood samples collected from the foxes were tested in the laboratory by a battery of polymerase chain reaction (PCR) assays targeting bacteria of the genera Rickettsia, Borrelia, Coxiella, Anaplasma, and Ehrlichia; and protozoa of the genera Babesia, Hepatozoon, and Leishmania. Of the targeted organisms, evidence of infection in the foxes was detected for Ehrlichia and Hepatozoon organisms only. Overall, six (10.3%) foxes were infected by an ehrlichial agent closely related to an ehrlichial agent recently detected in free-ranging Jaguars [(Panthera onca (L.)] in central-western Brazil, and to Ehrlichia ruminantium. For Hepatozoon, 28 (48.3%) foxes were infected by an agent closely related to Hepatozoon sp. Curupira 2 and H. americanum; and one (1.7%) fox was infected by an organism closely related to reptile-associated Hepatozoon agents. Finally, 11 (19.0%) foxes were found infested by Amblyomma cajennense (F.) nymphs, which were all PCR negative for the range of vector-borne agents cited above. Because the haplotypes found in free-ranging foxes are genetically closely related to pathogens of great veterinary importance, namely E. ruminantium and H. americanum, it is highly desirable to know if these novel organisms have any important role as agents of diseases in domestic animals and wildlife in Brazil.

Identificación morfológica de Ehrlichia sp. en las plaquetas de pacientes con infección por virus de la inmunodeficiencia humana, en Venezuela Morphologic identification of Ehrlichia sp. in the platelets of patients infected with the human immunodeficiency virus in Venezuela

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Irene del Carmen de Tamí

2004-11-01

Full Text Available OBJETIVO: Determinar la frecuencia de infección por bacterias del género Ehrlichia en una población de pacientes con infección por virus de la inmunodeficiencia humana (VIH. Como se sabe, la infección por VIH suele culminar en el síndrome de inmunodeficiencia adquirida (SIDA después de un período variable en que la persona queda expuesta a distintos tipos de infecciones oportunistas, cuya gravedad varía según el deterioro de su sistema inmunitario. La ehrliquiosis humana es una enfermedad infecciosa de reconocimiento reciente que se transmite por garrapatas y que es causada por especies de Ehrlichia. Se trata de microorganismos gramnegativos, intracelulares obligados, que muestran tropismo por células sanguíneas (leucocitos y plaquetas. En Venezuela se identificó por primera vez en seres humanos en 1994, con la detección de microcolonias (mórulas en el citoplasma de plaquetas. MATERIAL Y MÉTODOS: Para el estudio se reunieron muestras de sangre periférica de 87 pacientes con seropositividad a VIH recibidos en el Laboratorio de Inmunología del Instituto de Oncología y Hematología, en Caracas, Venezuela, que es uno de los centros de referencia nacionales para casos de infección por VIH. Se revisaron retrospectivamente, al microscopio óptico, frotis elaborados con capa blanca sanguínea concentrada, teñidos con colorante de Wright y sellados con resina para su conservación. RESULTADO: Se identificó Ehrlichia trombocítica en 12 de los 87 sujetos del estudio, es decir, en 13,8%. CONCLUSIÓN: La identificación de Ehrlichia trombocítica en pacientes seropositivos sugiere la necesidad de tener en cuenta la ehrliquiosis como posible diagnóstico en la población con infección por VIH.OBJECTIVE: To determine the frequency of infection by bacteria of the genus Ehrlichia in a population of patients infected with the human immunodeficiency virus (HIV. As is widely recognized, HIV infection is usually followed by the acquired

Rangelia vitalii, Babesia spp. and Ehrlichia spp. in dogs in Passo Fundo, state of Rio Grande do Sul, Brazil

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Juliana Gottlieb

2016-06-01

Full Text Available Abstract Pathogens transmitted by ticks are an emerging problem worldwide, this study aimed to diagnose the causal agents of infection in dogs presenting suspected hemoparasitoses. Fifty-eight dogs with clinical signs such as depression, hemorrhagic diathesis and fever were evaluated regarding clinical presentation, hemogram, blood smears and serological tests, using the indirect immunofluorescence method for the agents Babesia vogeli and Ehrlichia canis and conventional PCR for Babesia spp. (gene 18S rRNA, Rangelia vitalii (gene 18S rRNA and Ehrlichia spp. (gene dsb. Five (8.6% of the 58 dogs were serologically positive for Babesia spp. and three (5.1% for E. canis. Four dogs (6.8% were positive for R. vitalii through the molecular diagnosis. The PCR products were sequenced and the DNA from R. vitalii was found to be 99% genetically identical to samples of R. vitalii that had been isolated in Brazil. No presence of Babesia spp. or E. canis was observed through PCR on the dogs evaluated here. The results indicate the presence of R. vitalii and exposure to Babesia spp. and Ehrlichia spp. among the dogs analyzed.

Comparison of Ehrlichia muris Strains Isolated from Wild Mice and Ticks and Serologic Survey of Humans and Animals with E. muris as Antigen

OpenAIRE

Kawahara, Makoto; Ito, Tadahiko; Suto, Chiharu; Shibata, Shinichiro; Rikihisa, Yasuko; Hata, Kazuhisa; Hirai, Katsuya

1999-01-01

In metropolitan Tokyo, the Ehrlichia muris seropositivity rate of 24 wild mice was 63% in Hinohara Village, but in the surrounding areas, it was 0 to 5%. This finding suggests that the reservoir of E. muris is focal. Among the 15 seropositive mice, ehrlichiae were isolated from 9 Apodemus speciosus mice and 1 A. argenteus mouse, respectively. Five ehrlichial isolates were obtained from 10 ticks (Haemaphysalis flava) collected in Asuke Town, Aichi Prefecture, where the E. muris type strain had...

Case report of canine co-infection with Leishmania infantum and Ehrlichia canis

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Stefanovska Jovana

2011-05-01

Full Text Available Canine leishmaniasis (CanL due to Leishmania infantum and canine monocytic ehrilichiosis (CME due to Ehrlichia canis are common diseases with zoonotic potential in the Mediterranean area. Their prevalence in R. Macedonia as a neighboring Mediterranean county is expected. In both diseases similar clinical symptoms can be manifested in dogs such as: lethargy, anorexia, weight loss, epistaxis, fever, pale mucous membranes, enlarged lymph nodes, splenomegaly, ocular signs. This case report present an atypical case of 11 year old female Samoyed with starting single clinical symptom epistaxys. Initial diagnostic procedures revealed the presence only of CanL, which was diagnosed using indirect immunofluorescence method and ELISA. First laboratory findings showed normal hematological and renal profiles. Dog was put on a treatment with Allopurinol (20mg/kg, p/o for at least 9 months. Termination of the therapy after 6 months brought a numerous clinical symptoms involving weakness, dehydration, pale mucous membranes lost pupilar reflex, uremic breath and biochemical parameters revealed a renal failure. Using a commercial ELISA kit Ehrlichia canis as a co infection was diagnosed. Most probably the second infectious agent was induced in the past 6 months, causing more severe pathological effects than CanL infection alone.

Experimental inoculation of beagle dogs with Ehrlichia species detected from Ixodes ovatus

OpenAIRE

Watanabe, Malaika; Oikawa, T; Hiraoka, Hiroko; Kaneko, N; Itamoto, Kazuhito; Mizuno, Tohru; Okuda, Masaru; Inokuma, Hisashi

2006-01-01

Three beagle dogs were inoculated with mice spleen/liver homogenate infected with Ehrlichia species detected from Ixodes ovatus (EIO) and one dog was used as a control. All three infected dogs did not show clinical signs of disease except for mild pyrexia throughout the 41-day study period. Splenomegaly was observed from Day 7 post-inoculation (p.i.) in two of the dogs. Hematological and biochemical abnormalities included mild thrombocytopenia, hypoproteinaemia, hypoalbuminaemia and increased...

Molecular detection of Anaplasma bovis, Ehrlichia canis and Hepatozoon felis in cats from Luanda, Angola.

Science.gov (United States)

Oliveira, Ana Cristina; Luz, Maria Francisca; Granada, Sara; Vilhena, Hugo; Nachum-Biala, Yaarit; Lopes, Ana Patrícia; Cardoso, Luís; Baneth, Gad

2018-03-20

Molecular identification of tick-borne pathogen infection in cats from Africa is scarce. The presence of bacterial (Anaplasma and Ehrlichia) and protozoal (Babesia and Hepatozoon) agents was investigated in blood samples from 102 domestic cats from Luanda, Angola, by polymerase chain reaction and DNA sequencing. Three cats (2.9%) were found infected with Ehrlichia canis, three (2.9%) with Hepatozoon felis and one (1.0%) with Anaplasma bovis. The prevalence of infections with one single agent was 4.9%, and that of infection with two agents (i.e. E. canis and H. felis) was 1.0%. In total, six cats (5.9%) were found infected with at least one of the detected tick-borne agents. This is the first report of A. bovis, E. canis and H. felis in cats from Angola. To the best of our knowledge, A. bovis is also being reported for the first time in domestic cats outside of Japan. Cats are at a low to moderate risk of being infected with tick-borne agents in Luanda.

Detection of a Rickettsia Closely Related to Rickettsia aeschlimannii, “Rickettsia heilongjiangensis,” Rickettsia sp. Strain RpA4, and Ehrlichia muris in Ticks Collected in Russia and Kazakhstan

OpenAIRE

Shpynov, Stanislav; Fournier, Pierre-Edouard; Rudakov, Nikolay; Tankibaev, Marat; Tarasevich, Irina; Raoult, Didier

2004-01-01

Using PCR, we screened 411 ticks from four genera collected in Russia and Kazakhstan for the presence of rickettsiae and ehrlichiae. In Russia, we detected “Rickettsia heilongjiangensis,” Rickettsia sp. strain RpA4, and Ehrlichia muris. In Kazakhstan, we detected Rickettsia sp. strain RpA4 and a rickettsia closely related to Rickettsia aeschlimannii. These agents should be considered in a differential diagnosis of tick-borne infections in these areas.

In vitro culture and structural differences in the major immunoreactive protein gp36 of geographically distant Ehrlichia canis isolates

Czech Academy of Sciences Publication Activity Database

Zweygarth, E.; Cabezas Cruz, Alejandro; Josemans, A.I.; Oosthuizen, M.C.; Matjila, P.T.; Lis, K.; Broniszewska, M.; Schöl, H.; Ferrolho, J.; Grubhoffer, Libor; Passos, L.M.F.

2014-01-01

Roč. 5, č. 4 (2014), s. 423-431 ISSN 1877-959X Institutional support: RVO:60077344 Keywords : Ehrlichia canis * In vitro culture * IDE8 tick cells * DH82 * 16S rRNA * gp36 Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 2.718, year: 2014

Ticks and tick-borne pathogens and putative symbionts of black bears (Ursus americanus floridanus) from Georgia and Florida.

Science.gov (United States)

Yabsley, Michael J; Nims, Todd N; Savage, Mason Y; Durden, Lance A

2009-10-01

Ticks were collected from 38 black bears (Ursus americanus floridanus) from northwestern Florida (n = 18) from 2003 to 2005 and southern Georgia (n = 20) in 2006. Five species (Amblyomma americanum, A. maculatum, Dermacentor variabilis, Ixodes scapularis, and I. affinis) were collected from Florida bears, and 4 species (A. americanum, A. maculatum, D. variabilis, I. scapularis) were collected from bears in Georgia. Ixodes scapularis was the most frequently collected tick, followed by D. variabilis, A. americanum, A. maculatum, and I. affinis. The collection of I. affinis from a Florida bear represents a new host record. A subset of ticks was screened for pathogens and putative symbionts by polymerase chain reaction (PCR). The zoonotic tick-borne pathogens Ehrlichia chaffeensis and Rickettsia parkeri were detected in 1 of 23 (4.3%) A. americanum and 1 of 12 (8.3%) A. maculatum, respectively. The putative zoonotic pathogen "Rickettsia amblyommii" was detected in 4 (17.4%) A. americanum and 1 (8.3%) A. maculatum. Other putative symbiotic rickettsiae detected included R. bellii and R. montanensis in D. variabilis, a Rickettsia cooleyi-like sp. and Rickettsia sp. Is-1 in I. scapularis, and Rickettsia TR39-like sp. in I. scapularis and A. americanum. All ticks were PCR-negative for Anaplasma phagocytophilum, Panola Mountain Ehrlichia sp., E. ewingii, Francisella tularensis, and Borrelia spp.

Comparative Analysis of Wolbachia Genomes Reveals Streamlining and Divergence of Minimalist Two-Component Systems

Science.gov (United States)

Christensen, Steen; Serbus, Laura Renee

2015-01-01

Two-component regulatory systems are commonly used by bacteria to coordinate intracellular responses with environmental cues. These systems are composed of functional protein pairs consisting of a sensor histidine kinase and cognate response regulator. In contrast to the well-studied Caulobacter crescentus system, which carries dozens of these pairs, the streamlined bacterial endosymbiont Wolbachia pipientis encodes only two pairs: CckA/CtrA and PleC/PleD. Here, we used bioinformatic tools to compare characterized two-component system relays from C. crescentus, the related Anaplasmataceae species Anaplasma phagocytophilum and Ehrlichia chaffeensis, and 12 sequenced Wolbachia strains. We found the core protein pairs and a subset of interacting partners to be highly conserved within Wolbachia and these other Anaplasmataceae. Genes involved in two-component signaling were positioned differently within the various Wolbachia genomes, whereas the local context of each gene was conserved. Unlike Anaplasma and Ehrlichia, Wolbachia two-component genes were more consistently found clustered with metabolic genes. The domain architecture and key functional residues standard for two-component system proteins were well-conserved in Wolbachia, although residues that specify cognate pairing diverged substantially from other Anaplasmataceae. These findings indicate that Wolbachia two-component signaling pairs share considerable functional overlap with other α-proteobacterial systems, whereas their divergence suggests the potential for regulatory differences and cross-talk. PMID:25809075

Canine infection with Borrelia burgdorferi, Dirofilaria immitis, Anaplasma spp. and Ehrlichia spp. in Canada, 2013-2014.

Science.gov (United States)

Herrin, Brian H; Peregrine, Andrew S; Goring, Jonas; Beall, Melissa J; Little, Susan E

2017-05-19

Canine test results generated by veterinarians throughout Canada from 2013-2014 were evaluated to assess the geographical distribution of canine infection with Borrelia burgdorferi, Dirofilaria immitis, Ehrlichia spp., and Anaplasma spp. The percent positive test results of 115,636 SNAP® 4Dx® Plus tests from dogs tested were collated by province and municipality to determine the distribution of these vector-borne infections in Canada. A total of 2,844/115,636 (2.5%) dogs tested positive for antibody to B. burgdorferi. In contrast, positive test results for D. immitis antigen and antibodies to Ehrlichia spp. and Anaplasma spp. were low, with less than 0.5% of dogs testing positive for any one of these three agents nationwide. Provincial seroprevalence for antibodies to B. burgdorferi ranged from 0.5% (Saskatchewan)-15.7% (Nova Scotia); the areas of highest percent positive test results were in proximity to regions in the USA considered endemic for Lyme borreliosis, including Nova Scotia (15.7%) and Eastern Ontario (5.1%). These high endemic foci, which had significantly higher percent positive test results than the rest of the nation (P Canada. Using dogs as sentinels for these pathogens can aid in recognition of the public and veterinary health threat that each pose.

Ehrlichia canis morulae and DNA detection in whole blood and spleen aspiration samples.

Science.gov (United States)

Faria, Joice Lara Maia; Dagnone, Ana Sílvia; Munhoz, Thiago Demarchi; João, Carolina Franchi; Pereira, Wanderson Adriano Biscola; Machado, Rosângela Zacarias; Tinucci-Costa, Mirela

2010-01-01

The aim of this study was to compare the detection of Ehrlichia canis morulae and DNA by nPCR in whole blood and spleen aspiration. The sample included 40 dogs showing thrombocytopenia associated to clinical signs suggestive of canine ehrlichiosis. Morulae detection showed that in 35 of the dogs studied, 17 had morulae in spleen tissue, and two in buffy coat smears. E. canis DNA was detected in 29/40 blood samples. We verified that morulae detection is more efficient in cytological preparations from spleen aspiration. On the other hand, nPCR on spleen and blood samples were equally efficient for disease diagnosis.

Detection of Rickettsia and Ehrlichia spp. in Ticks Associated with Exotic Reptiles and Amphibians Imported into Japan.

Science.gov (United States)

Andoh, Masako; Sakata, Akiko; Takano, Ai; Kawabata, Hiroki; Fujita, Hiromi; Une, Yumi; Goka, Koichi; Kishimoto, Toshio; Ando, Shuji

2015-01-01

One of the major routes of transmission of rickettsial and ehrlichial diseases is via ticks that infest numerous host species, including humans. Besides mammals, reptiles and amphibians also carry ticks that may harbor Rickettsia and Ehrlichia strains that are pathogenic to humans. Furthermore, reptiles and amphibians are exempt from quarantine in Japan, thus facilitating the entry of parasites and pathogens to the country through import. Accordingly, in the current study, we examined the presence of Rickettsia and Ehrlichia spp. genes in ticks associated with reptiles and amphibians originating from outside Japan. Ninety-three ticks representing nine tick species (genera Amblyomma and Hyalomma) were isolated from at least 28 animals spanning 10 species and originating from 12 countries (Ghana, Jordan, Madagascar, Panama, Russia, Sri Lanka, Sudan, Suriname, Tanzania, Togo, Uzbekistan, and Zambia). None of the nine tick species are indigenous in Japan. The genes encoding the common rickettsial 17-kDa antigen, citrate synthase (gltA), and outer membrane protein A (ompA) were positively detected in 45.2% (42/93), 40.9% (38/93), and 23.7% (22/93) of the ticks, respectively, by polymerase chain reaction (PCR). The genes encoding ehrlichial heat shock protein (groEL) and major outer membrane protein (omp-1) were PCR-positive in 7.5% (7/93) and 2.2% (2/93) of the ticks, respectively. The p44 gene, which encodes the Anaplasma outer membrane protein, was not detected. Phylogenetic analysis showed that several of the rickettsial and ehrlichial sequences isolated in this study were highly similar to human pathogen genes, including agents not previously detected in Japan. These data demonstrate the global transportation of pathogenic Rickettsia and Ehrlichia through reptile- and amphibian-associated ticks. These imported animals have potential to transfer pathogens into human life. These results highlight the need to control the international transportation of known and

Detection of Rickettsia and Ehrlichia spp. in Ticks Associated with Exotic Reptiles and Amphibians Imported into Japan.

Directory of Open Access Journals (Sweden)

Masako Andoh

Full Text Available One of the major routes of transmission of rickettsial and ehrlichial diseases is via ticks that infest numerous host species, including humans. Besides mammals, reptiles and amphibians also carry ticks that may harbor Rickettsia and Ehrlichia strains that are pathogenic to humans. Furthermore, reptiles and amphibians are exempt from quarantine in Japan, thus facilitating the entry of parasites and pathogens to the country through import. Accordingly, in the current study, we examined the presence of Rickettsia and Ehrlichia spp. genes in ticks associated with reptiles and amphibians originating from outside Japan. Ninety-three ticks representing nine tick species (genera Amblyomma and Hyalomma were isolated from at least 28 animals spanning 10 species and originating from 12 countries (Ghana, Jordan, Madagascar, Panama, Russia, Sri Lanka, Sudan, Suriname, Tanzania, Togo, Uzbekistan, and Zambia. None of the nine tick species are indigenous in Japan. The genes encoding the common rickettsial 17-kDa antigen, citrate synthase (gltA, and outer membrane protein A (ompA were positively detected in 45.2% (42/93, 40.9% (38/93, and 23.7% (22/93 of the ticks, respectively, by polymerase chain reaction (PCR. The genes encoding ehrlichial heat shock protein (groEL and major outer membrane protein (omp-1 were PCR-positive in 7.5% (7/93 and 2.2% (2/93 of the ticks, respectively. The p44 gene, which encodes the Anaplasma outer membrane protein, was not detected. Phylogenetic analysis showed that several of the rickettsial and ehrlichial sequences isolated in this study were highly similar to human pathogen genes, including agents not previously detected in Japan. These data demonstrate the global transportation of pathogenic Rickettsia and Ehrlichia through reptile- and amphibian-associated ticks. These imported animals have potential to transfer pathogens into human life. These results highlight the need to control the international transportation of known

JAERI tandem-accelerator and tandem-booster

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Tadashi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-03-01

In 1982, aiming at the new development of atomic energy research, the tandem accelerator of Japan Atomic Energy Research Institute (JAERI) was installed. In fiscal year 1993, the superconducting boosters which can increase the ion energy by up to 4 times were added, and the research in the region below 1000 MeV became possible. Those are electrostatic type accelerators which are easy to be used especially in basic research field, and are useful for future research. The tandem accelerator has been operated while maintaining the first class performance as the accelerator for various kinds of heavy ion beam. It has the special shape among electrostatic type accelerators, and is excellent in the easiness of control and stability. The main particulars of the tandem accelerator are shown. As for the ion sources of the tandem accelerator, three cesium sputter type ion sources are installed on two high voltage stands. The kinds of the ions which can be accelerated are mainly negative ions. As the improvement, electron cyclotron resonance (ECR) ion sources are expected to be adopted. As for the tandem boosters, the 1/4 wavelength type resonance hollow cylinder was adopted. The constitution of the tandem boosters is explained. The way of utilizing the tandem accelerator system and the aim for hereafter are reported. (K.I.)

Survey of Ehrlichia canis, Babesia spp. and Hepatozoon spp. in dogs from a semiarid region of Brazil

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Tereza Emmanuelle de Farias Rotondano

Full Text Available This study assessed the occurrence of Ehrlichia spp., Babesia spp. and Hepatozoon spp. infections in 100 tick-harboring dogs from a semiarid region of the State of Paraíba, Northeastern Brazil. Blood samples and ticks were collected from the animals, and a questionnaire was submitted to dog owners to obtain general data. Blood samples were used to perform hemogram, direct blood smear and immunological and molecular hemoparasite detection. The 1,151 ticks collected were identified as Rhipicephalus sanguineus; direct smears revealed E. canis-like morulae in the monocytes of 4% (4/100 of the non-vaccinated female dogs, and 34% and 25% of the dogs tested positive for Ehrlichia canis by indirect immunofluorescence assay (IFA and polymerase chain reaction (PCR, respectively. Blood smear examination revealed Babesia-suggestive merozoites in the erythrocytes of 2% (2/100 of the animals. Babesia vogeli was detected by PCR in ten animals (10% and was correlated with young age (p = 0.007 and thrombocytopenia (p = 0.01. None of the animals showed Hepatozoon spp. positivity. These results indicate that E. canis is the main tick-borne canine pathogen in the study area and provide the first report of B. vogeli infection in dogs from Paraiba State.

Survey of Ehrlichia canis, Babesia spp. and Hepatozoon spp. in dogs from a semiarid region of Brazil.

Science.gov (United States)

Rotondano, Tereza Emmanuelle de Farias; Almeida, Herta Karyanne Araújo; Krawczak, Felipe da Silva; Santana, Vanessa Lira; Vidal, Ivana Fernandes; Labruna, Marcelo Bahia; de Azevedo, Sérgio Santos; Ade lmeida, Alzira Maria Paiva; de Melo, Marcia Almeida

2015-01-01

This study assessed the occurrence of Ehrlichia spp., Babesia spp. and Hepatozoon spp. infections in 100 tick-harboring dogs from a semiarid region of the State of Paraíba, Northeastern Brazil. Blood samples and ticks were collected from the animals, and a questionnaire was submitted to dog owners to obtain general data. Blood samples were used to perform hemogram, direct blood smear and immunological and molecular hemoparasite detection. The 1,151 ticks collected were identified as Rhipicephalus sanguineus; direct smears revealed E. canis-like morulae in the monocytes of 4% (4/100) of the non-vaccinated female dogs, and 34% and 25% of the dogs tested positive for Ehrlichia canis by indirect immunofluorescence assay (IFA) and polymerase chain reaction (PCR), respectively. Blood smear examination revealed Babesia-suggestive merozoites in the erythrocytes of 2% (2/100) of the animals. Babesia vogeli was detected by PCR in ten animals (10%) and was correlated with young age (p = 0.007) and thrombocytopenia (p = 0.01). None of the animals showed Hepatozoon spp. positivity. These results indicate that E. canis is the main tick-borne canine pathogen in the study area and provide the first report of B. vogeli infection in dogs from Paraiba State.

Investigação molecular de Ehrlichia spp. e Anaplasma platys em felinos domésticos: alterações clínicas, hematológicas e bioquímicas

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Elisabete S Correa

2011-10-01

Full Text Available Ehrlichia sp. e Anaplasma platys são micro-organismos Gram negativos, parasitos intracelulares obrigatórios, residindo em vacúolos citoplasmáticos de leucócitos e plaquetas, encontrados no sangue periférico ou em tecidos. Poucos relatos têm sido feitos sobre erliquiose e anaplasmose em gatos no Brasil, os quais são baseados na presença de mórulas em leucócitos e plaquetas, ou pela detecção de anticorpos. O objetivo deste trabalho foi investigar a infecção natural por Ehrlichia sp. e A.platys em gatos no Município de Campos dos Goytacazes-RJ, através da hematoscopia e pela detecção do DNA desses agentes. Foram utilizadas amostras de sangue total e de soro de 91 gatos, independente de raça, sexo e idade. Realizaram-se hemograma, bioquímica sérica e PCR, utilizando oligonucleotídes para Ehrlichia sp. e A.platys. Os dados de hematoscopia mostraram que 9,89% dos gatos apresentaram mórulas em macroplaquetas. O DNA de A.platys foi detectado em 13,18% dos 91 animais e em 44,44% das amostras positivas à hematoscopia. O DNA de Ehrlichia sp. não foi detectado em nenhuma amostra. Nenhuma alteração foi observada nos sinais clínicos nem nos resultados laboratoriais nos animais estudados. Os dados sugerem que os felinos domésticos podem atuar como potenciais reservatórios para A. platys, como forma não sintomática das enfermidades relacionadas

Possible death of a buffalo calf (Syncercus caffer due to suspected heartwater (Ehrlichia ruminantium : clinical communication

Directory of Open Access Journals (Sweden)

S. Pfitzer

2004-06-01

Full Text Available Rickettsial organisms resembling Ehrlichia ruminantium (the causative organism of heartwater were demonstrated in brain smears and formalin-fixed brain sections derived from a buffalo calf that died on a private game reserve in northern KwaZulu-Natal. The possibility that the tick-free environment of a quarantine boma may have affected the calf 's immunity, is discussed. These findings suggest that monitoring heartwater in wild ruminants and making brain smears as a routine during post mortem evaluations of wild ruminants, should be encouraged.

Antibodies to granulocytic ehrlichiae in white-footed and cotton mice in eastern United States.

Science.gov (United States)

Magnarelli, L A; Stafford, K C; Ijdo, J W; Fikrig, E; Oliver, J H; Hutcheson, H J; Boone, J L

1999-04-01

Serum samples, collected from Peromyscus leucopus (white-footed mouse) or Peromyscus gossypinus (cotton mouse) during 1987 through 1990 in Florida, Georgia, Maryland, Mississippi, and North Carolina (USA), and in 1997 in southern Connecticut were analyzed by indirect fluorescent antibody (IFA) staining methods or Western blot procedures for antibodies to granulocytic ehrlichiae. Of the 82 sera from white-footed mice in Connecticut tested by IFA methods with either the BDS or NCH-1 strain of the human granulocytic ehrlichiosis (HGE) agent, 45 (55%) and 42 (51%) of the samples contained antibodies to these strains, respectively, at concentrations ranging from 1:80 to 1:2560. One (2%) of 43 sera from P. leucopus captured in Assateague Island (Maryland) had a titer of 1:80, while three (20%) of 15 sera from P. gossypinus, captured in Sapelo Island (Georgia) and four (40%) of 10 sera from cotton mice caught in Amelia Island (Florida) had antibodies to the NCH-1 strain at titers of 1:160 to 1:1,280. Fifty-five sera from P. leucopus in Cape Hatteras (North Carolina) and 30 sera from P. gossypinus in Mississippi were negative. Western blot analyses confirmed seropositivity for 19 (95%) of 20 mouse sera positive by IFA staining methods, including samples from both mouse species captured in Connecticut, Maryland, or Florida. There were key banding patterns to proteins having molecular masses of about 44, 80, 105, 110, or 120 kDa. Both serologic assays can be used to determine if mice have been exposed to granulocytic ehrlichiae. These rodents also may be useful in surveillance programs to identify endemic sites for HGE and in performing laboratory studies on immune responses to the etiologic agent.

Prevalence and diversity of Babesia, Hepatozoon, Ehrlichia, and Bartonella in wild and domestic carnivores from Zambia, Africa.

Science.gov (United States)

Williams, Brianna M; Berentsen, Are; Shock, Barbara C; Teixiera, Maria; Dunbar, Michael R; Becker, Matthew S; Yabsley, Michael J

2014-03-01

A molecular survey was conducted for several hemoparasites of domestic dogs and three species of wild carnivores from two sites in Zambia. Three Babesia spp. were detected including Babesia felis and Babesia leo in lions (Panthera leo) and a Babesia sp. (similar to Babesia lengau) in spotted hyenas (Crocuta crocuta) and a single lion. All wild dogs (Lycaon pictus) and domestic dogs were negative for Babesia. High prevalences for Hepatozoon were noted in all three wild carnivores (38-61%) and in domestic dogs (13%). Significantly higher prevalences were noted in hyenas and wild dogs compared with domestic dogs and lions. All carnivores were PCR negative for Ehrlichia canis, Ehrlichia ewingii, and Bartonella spp. Overall, high prevalences and diversity of Babesia and Hepatozoon were noted in wild carnivores from Zambia. This study is the first molecular characterization of Babesia from any hyena species and is the first report of a Babesia sp. closely related to B. lengau, a parasite previously only reported from cheetahs (Acinonyx jubatus), in lions and hyenas. Although usually benign in wild carnivores, these hemoparasites can be pathogenic under certain circumstances. Importantly, data on vectors for these parasites are lacking, so studies are needed to identify vectors as well as determine transmission routes, infection dynamics, and host specificity of these hemoparasites in wildlife in Africa and also the risk of transmission between domestic animals and wildlife.

Prevalence of Ehrlichia canis using the nested-PCR, correlation with the presence of morulae and thrombocytopenia in dogs treated in Veterinary Hospital of the Federal University of Espirito Santo

Directory of Open Access Journals (Sweden)

Mara Rúbia Rocha Pereira Sales

2015-03-01

Full Text Available ABSTRACT. Sales M.R.R.P., Ignacchiti M.D.C., Mendes Junior A.F., Suhett W.G., Porfírio L.C., Marins M., Aptekmann K.P. & Pereira Júnior O.S. [Prevalence of Ehrlichia canis using the nested-PCR, correlation with the presence of morulae and thrombocytopenia in dogs treated in Veterinary Hospital of the Federal University of Espirito Santo.] Prevalência de Ehrlichia canis pela Nested- -PCR, correlação com a presença de mórula e trombocitopenia em cães atendidos no Hospital Veterinário da Universidade Federal do Espírito Santo. Revista Brasileira de Medicina Veterinária, 37(1:47-51, 2015. Centro de Ciências Agrárias, Universidade Federal do Espírito Santo, Rua Projetada s/nº, Caixa Postal 25, Pontal, Marataízes, ES 29349-000, Brasil. E-mail: mararrps@yahoo.com.br Ehrlichia canis, is the primary etiologic agent of canine monocytic ehrlichiosis. The disease is mainly transmitted by the brown dog ticks Rhipicephalus sanguineus in different endemic regions of Brazil. The purpose of this study was determinated using the Nested Polymerase Chain Reaction (nested-PCR the prevalence of Ehrlichia canis in 85 dogs, regardless of race, age, sex or health status, treated at the Veterinary Hospital of Federal University of Espirito Santo, in Alegre-ES and evaluate its correlation with the presence of morulae and thrombocytopenia. It was observed that 1.17% of the samples were positive by blood smear, for the presence of morulae. However, the nested-PCR showed 5.88% positivity of samples. And 17.64% samples showed thrombocytopenia. By analyzing all the techniques, it was concluded that the introduction of diagnostic techniques such as nested-PCR is an important method for aid in early diagnosis of pathologies.

Ehrlichia canis and Anaplasma platys in ticks of dogs in Cuiaba, Mato GrossoEhrlichia canis e Anaplasma platys em carrapatos de cães de Cuiabá, Mato Grosso

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Valéria Dutra

2012-06-01

Full Text Available Diseases transmitted by arthropods such as Rhipicephalus sanguineus, are caused by a spectrum of pathogens. Among these are the canine monocytic ehrlichiosis and cyclical thrombocytopenia with a cosmopolitan distribution. Aiming to verify the presence of DNA of Anaplasma platys and Ehrlichia canis in ticks R. sanguineus collected in the period 2008 to 2009 of 380 infected dogs. Ticks, after maceration, were subjected to DNA extraction and then nested PCR was performed for amplification of A. platys and E. canis. Of these, 81 (29.7% amplified DNA from ehrlichiais agents, where 38 (17.9% amplified in E. canis and 32 (15.7% for A. platys. The observation of two pathogens, combined with worldwide distribution of the tick R. sanguineus, demonstrates the high risk of infection with these pathogens in dogs in the city of Cuiaba. Doenças transmitidas por artrópodes, como o Rhipicephalus sanguineus, são causadas por um espectro de patógenos. Dentre estas, estão a erliquiose monocítica canina e trombocitopenia cíclica com distribuição cosmopolita. Com o objetivo de verificar a presença de DNA de Anaplasma platys e Ehrlichia canis em carrapatos R. sanguineus coletados no período de 2008 a 2009 de 380 cães infestados. Os carrapatos, após a maceração, foram submetidos a extração de DNA e, em seguida, foi realizada a Nested PCR para a amplificação da espécie A. platys e E. canis. Destes, 81 (29.7% amplificaram o DNA dos agentes ehrlichiais, onde 38 (17.9% amplificaram para E. canis e 32 (15.7% para A. platys. A observação dos dois patógenos, combinado com distribuição mundial do carrapato R. sanguineus, demonstra o elevado risco de infecção por esses patógenos de cães na cidade de Cuiabá.

Babesia canis vogeli, Ehrlichia canis, and Anaplasma platys infection in a dog.

Science.gov (United States)

Al Izzi, Salah; Martin, Donald S; Chan, Roxanne Y Y; Leutenegger, Christian M

2013-12-01

A 12-month-old male neutered mixed breed dog was presented with a history of diarrhea, lethargy, emaciation, polydypsia, and sniffling. Physical examination findings included pale mucous membranes, increased heart and respiratory rates, and normal rectal temperature (38°C). Hematologic abnormalities included anemia and thrombocytopenia. Biochemical abnormalities included hypoalbuminemia, hyperbilirubinemia, and elevated ALP and ALT activities. A SNAP 4Dx test result was positive for Ehrlichia canis. Babesia canis vogeli organisms were found in the peripheral blood films, while morulae of E canis were not seen. Real-time polymerase chain reaction testing confirmed the presence of both B c vogeli and E canis organisms, and also was positive for Anaplasma platys infection. The dog recovered following treatment with doxycycline and imidocarb dipropionate, with normal hematology and biochemical profiles. © 2013 American Society for Veterinary Clinical Pathology.

Soroprevalência de anticorpos anti-Ehrlichia canis em cães de Cuiabá, Mato Grosso Seroprevalence anti-Ehrlichia canis antibodies in dogs of Cuiabá, Mato Grosso

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José Nivaldo da Silva

2010-06-01

Full Text Available A erliquiose canina é uma doença transmitida por carrapatos Rhipicephalus sanguineus e ocasionada pela Ehrlichia canis, bactéria intracelular obrigatória. O presente estudo verificou a prevalência de anticorpos anti-E. canis em 254 cães de quatro regiões administrativas de Cuiabá, Estado de Mato Grosso, por imunofluorescência indireta, observando-se uma prevalência de 42,5% (108/254 sem diferença significativa entre as regiões. As variáveis idade, raça, sexo, hábitat, acesso à zona rural e presença de carrapatos foram analisadas. Os títulos de anticorpos variaram entre 1:40 a 1:2.560. Somente 32 (29,63% cães soropositivos estavam infestados por carrapatos, todos R. sanguineus. O resultado encontrado confirma que não há predisposição racial, sexual ou etária, enquanto a menor ocorrência de cães reagentes no intradomicílio provavelmente está relacionada à baixa infestação por carrapato, apesar de não ter sido observada diferença significativa entre os cães com ou sem a infestação com o carrapato vetor.Canine ehrlichiosis is a disease transmitted by ticks Rhipicephalus sanguineus and caused by Ehrlichia canis, obligatory intracellular bacteria. The present study examined the prevalence of anti-E. canis in 254 dogs from four administrative regions of Cuiabá, Mato Grosso, by indirect immunofluorescence assay. There was a prevalence of 42.5% (108/254 without significant difference between the studied regions. The variables age, breed, sex, habitat, access to rural and ticks were analyzed. The antibody titers ranged from 1:40 to 1:2,560. Only 32 (29.63% seropositive dogs were infested with ticks, all R. sanguineus. The results confirm that do not have breed, sex or age predisposition to ehrlichiosis due E. canis, while the lowest occurrence of reactive dogs indoors probably related to low tick infestation, although no significant difference between dogs with or without infestation with the tick vector.

Aspectos epidemiológicos, clínicos e hematológicos de 251 cães portadores de mórula de Ehrlichia spp. naturalmente infectados Epidemiological, clinical, and hematological aspects of 251 dogs naturally infected with Ehrlichia spp. morulae

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S. Borin

2009-06-01

Full Text Available Realizou-se um estudo retrospectivo dos aspectos epidemiológicos, sinais clínicos, dados de exame físico e alterações hematológicas da erliquiose em 251 cães naturalmente infectados por Ehrlichia spp. Dos 4407 casos atendidos em hospital veterinário no período de janeiro de 2002 a dezembro de 2003, verificou-se que 251 cães eram portadores de mórula de Ehrlichia spp. em leucócitos de sangue periférico. Destes, 48 foram eliminados das avaliações por apresentarem patologias concomitantes. Nos 203 cães restantes, verificou-se que houve maior ocorrência em fêmeas (61,1% e que a doença manteve-se constante durante todo o período avaliado. Observou-se que 38% encontravam-se na faixa etária entre um e 23 meses e 58,6% eram de raça definida. As principais alterações clínicas observadas foram apatia, anorexia/hiporexia, vômito, secreção oculonasal e esplenomegalia. Cento e cinco cães apresentaram temperatura retal entre 38 e 39,5°C. As alterações observadas com maior frequência no hemograma foram anemia, predominando o tipo normocítica normocrômica (58,2%; desvio nuclear de neutrófilos para a esquerda (67% e eosinopenia (58,1%.A study of epidemiological and clinical aspects, alterations of physical exams, and hematological changes of canine ehrlichiosis was performed. A retrospective study was performed in 4,407 dogs referred to a Veterinary Hospital from January 2002 to December 2003. Of all cases, 251 dogs showed Ehrlichia spp. morulae. Among these, 48 were excluded from the study due to other co-infection by other pathologies. In the other 203 evaluated dogs, females (61.1% were more infected than males. The dogs aged from one to 23 months (68.6% and 58.6% were definite breed. Emesis, apathy, anorexia/hypoxeria, spleenomegaly, and nasal discharge were the most common signs presented. Rectal temperature was 38 - 39.5ÚC in 105 dogs. The most usual changes seen during the hematological tests were normochromic and

Serodetection of Ehrlichia canis amongst dogs in central Namibia

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Rutendo Manyarara

2015-06-01

Full Text Available Ehrlichia canis is a major pathogen in dogs throughout Africa, yet it has not been reported in Namibia. The aim of this study was to determine the seroprevalence of canine ehrlichiosis in central Namibia using the ImmunoComb assay (Biogal, Galed Laboratories. The study included 76 dogs that presented to the Rhino Park Veterinary Clinic in the north-western suburb of Khomasdal, Windhoek, Namibia, as well as 30 stray dogs from the Windhoek branch of the Society for the Prevention of Cruelty to Animals. Of the 106 dogs tested, 53.8% were seropositive at titres > 1:80. Dogs that presented with symptoms of E. canis infection had a significantly higher seroprevalence (86.6% compared with apparently healthy dogs (41.6% (P = 0.00. Location of habitation was significant (P < 0.017, with a high percentage of dogs exposed to E. canis living in the northern or north-western part of Windhoek. As the first study to serologically establish E. canis as a major pathogen in dogs in central Namibia, it is notable that the highest proportion of seropositive dogs came from low-income areas. Further investigation is necessary to describe the ecology of this important tick-borne pathogen of companion animals in Namibia.

Molecular detection of bacteria in the families Rickettsiaceae and Anaplasmataceae in northern crested caracaras (Caracara cheriway)

Science.gov (United States)

Erwin, John A.; Fitak, Robert R.; Dwyer, James F.; Morrison, Joan L.; Culver, Melanie

2016-01-01

Bacterial pathogens of the families Anaplasmataceae and Rickettsiaceae are often spread to humans or other animals from bites from infected arthropod hosts. Recently, an increasing number of studies have implicated migratory birds in the circulation of these pathogens through the spread of arthropod vectors. However, few studies have examined the potential for resident bird populations to serve as reservoirs for these zoonoses. In this study, we used nested PCRs of the GroESL and 17 kDa genes to screen for Anaplasmataceae and Rickettsiaceae, respectively, in a resident population of the northern crested caracara (Caracara cheriway) from Florida (n = 55). Additionally, a small number (n = 6) of captive individuals from Texas were included. We identified one individual (1.64%) positive for Rickettsia felis and one (1.64%) positive for Ehrlichia chaffeensis; both these individuals were from Florida. Presence of these pathogens demonstrates that these birds are potential hosts; however, the low prevalence of infections suggests that these populations likely do not function as an ecological reservoir.

Rickettsioses emergentes e reemergentes numa região endêmica do Estado de Minas Gerais, Brasil Emerging and reemerging rickettsiosis in an endemic area of Minas Gerais State, Brazil

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Márcio A. M. Galvão

2002-12-01

Full Text Available O trabalho descreve um inquérito sorológico para rickettsioses em escolares e cães de Novo Cruzeiro, Minas Gerais, Brasil, em 1998. Trezentos e trinta e um escolares pertenciam a uma área endêmica e 142 a uma área não endêmica do município. Trinta e nove (10,1% soros foram reativos à Reação de Imunofluorescência Indireta (RIFI para Rickettsia rickettsiino título de 1:64, sendo que dentre esses reativos, 35 eram de estudantes de escolas de área endêmica. Dentre os 73 cães analisados quanto à presença de anticorpos anti R. rickettsii, anti Ehrlichia chaffeensise anti Ehrlichia canisà RIFI no título de 1:64, 3 (4,11%, 11 (15,07% e 13 (17,81% desses animais foram reativos respectivamente aos antígenos testados. Conclui-se que, a sororeatividade para R. rickettsiiem indivíduos sadios sem história prévia de febre maculosa brasileira, uma doença marcante por sua alta letalidade, e a presença de sororeatividade para Ehrlichiacom potencial patogênico para o homem em cães, nos leva a indagar sobre a transmissão ao homem de outras espécies da família Rickettsiae na área estudada.This article describes a serological survey for rickettsiosis in the county of Novo Cruzeiro, Minas Gerais State, Brazil, in 1998, testing schoolchildren and dogs. Sera included 331 samples from schoolchildren from an endemic area and 142 samples from schoolchildren from a non-endemic area in the county. All children examined were healthy and had not reported clinical symptoms of Brazilian spotted fever prior to the serological survey. Some 35 children in the endemic area were reactive to Rickettsia rickettsiiby indirect fluorescent antibody (IFA with a titer of 1:64, corresponding to 10.6%. Sera from 73 dogs were tested, showing seroreactivity (IFA 1:64 to Rickettsia rickettsi, Ehrlichia chaffeensis, and Ehrlichia canisin 3 (4.11%, 11 (15.07%, and 13 (17.81%, respectively. The results in schoolchildren and the presence of canine seroreactivity to

Molecular detection of Ehrlichia canis in dogs from the Pantanal of Mato Grosso State, Brazil Detecção molecular de Ehrlichia canis em cães do Pantanal do Mato Grosso, Brasil

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Luana Gabriela Ferreira dos Santos

Full Text Available The present study evaluated the presence of Ehrlichia DNA in the blood samples of 320 dogs from the urban and rural areas of the municipality of Poconé, Pantanal region, Mato Grosso state, by Polymerase Chain Reaction (PCR, targeting the ehrlichial dsb gene. Risk factors for infection in dogs were also evaluated. Forty-eight (15%, 95% CI: 11.4-19.5% dogs were positive: 25 (15.6%, 95% CI: 10.4-22.2% from the urban area and 23 (14.4%, 95% CI: 9.3-20.8% from the rural area (P > 0.05. Partial DNA sequence obtained from PCR products of 18 samples from the urban area and 16 samples from the rural area were 100% identical to E. canis from Brazil and the USA. This study reports the first E. canis molecular detection in dogs from the northern Pantanal region.O presente estudo avaliou a presença de DNA de Ehrlichia spp. em 320 cães das áreas urbana e rural do município de Poconé, região do Pantanal de Mato Grosso, pela PCR visando o gene dsb. Os fatores de risco para a infecção em cães também foram avaliados. Quarenta e oito (15%, IC 95%: 11,4-19,5% cães foram positivos, 25 (15,6%, IC 95%: 10,4-22,2% da área urbana e 23 (14,37%, 95% CI: 9,3-20,8% da área rural (P > 0,05. Sequências parciais de DNAs obtidos a partir de produtos da PCR de 18 amostras da área urbana e 16 da área rural foram 100% idênticas a E. canis do Brasil e EUA. Este estudo relata a primeira detecção molecular de E. canis em cães da região norte do Pantanal.

Detection of Ehrlichia spp., Anaplasma spp., Rickettsia spp., and Other Eubacteria in Ticks from the Thai-Myanmar Border and Vietnam

OpenAIRE

Parola, Philippe; Cornet, Jean-Paul; Sanogo, Yibayiri Osée; Miller, R. Scott; Thien, Huynh Van; Gonzalez, Jean-Paul; Raoult, Didier; Telford III, Sam R.; Wongsrichanalai, Chansuda

2003-01-01

A total of 650 ticks, including 13 species from five genera, were collected from animals, from people, or by flagging of the vegetation at sites on the Thai-Myanmar border and in Vietnam. They were tested by PCR to detect DNA of bacteria of the order Rickettsiales. Three Anaplasma spp. were detected in ticks collected in Thailand, including (i) Anaplasma sp. strain AnDa465, which was considered a genotype of Anaplasma platys (formerly Ehrlichia platys) and which was obtained from Dermacentor ...

Comparison of Ehrlichia muris strains isolated from wild mice and ticks and serologic survey of humans and animals with E. muris as antigen.

Science.gov (United States)

Kawahara, M; Ito, T; Suto, C; Shibata, S; Rikihisa, Y; Hata, K; Hirai, K

1999-04-01

In metropolitan Tokyo, the Ehrlichia muris seropositivity rate of 24 wild mice was 63% in Hinohara Village, but in the surrounding areas, it was 0 to 5%. This finding suggests that the reservoir of E. muris is focal. Among the 15 seropositive mice, ehrlichiae were isolated from 9 Apodemus speciosus mice and 1 A. argenteus mouse, respectively. Five ehrlichial isolates were obtained from 10 ticks (Haemaphysalis flava) collected in Asuke Town, Aichi Prefecture, where the E. muris type strain had been isolated. These new isolates were compared with the E. muris type strain. The mouse virulence and ultrastructure of the new isolates were similar to those of the type strain, and all of them were cross-reactive with each other, as well as with the type strain, by indirect immunofluorescent-antibody test. The levels of similarity of the base sequences of the 16S rRNA gene of one of the A. speciosus isolates and one of the tick isolates to that of the E. muris type strain were 99.79 and 99.93%, respectively. We suggest that all of these isolates are E. muris; that E. muris is not limited to Eothenomys kageus but infects other species of mice; and that E. muris is present at locations other than Aichi Prefecture. It appears that H. flava is a potential vector of E. muris. Twenty (1%) of 1803 humans from metropolitan Tokyo were found to be seropositive for E. muris antibodies. A serological survey revealed that exposure to E. muris or organisms antigenically cross-reactive to E. muris occurred among dogs, wild mice, monkeys, bears, deer, and wild boars in Gifu Prefecture, nearby prefectures, and Nagoya City, central Japan. However, human beings and Rattus norvegicus rats in this area were seronegative. These results indicate broader geographic distribution of and human and animal species exposure to E. muris or related Ehrlichia spp. in Japan.

Canine vector-borne co-infections: Ehrlichia canis and Hepatozoon canis in the same host monocytes.

Science.gov (United States)

Baneth, Gad; Harrus, Shimon; Gal, Arnon; Aroch, Itamar

2015-02-28

The protozoon Hepatozoon canis and the rickettsia Ehrlichia canis are tick-borne pathogens, transmitted by Rhipicephalus sanguineus, which cause canine hepatozoonosis and canine monocytic ehrlichiosis, respectively. Co-infection of the same host monocytes with H. canis and E. canis confirmed by molecular characterization of the infecting agents and quantitative assessment of co-infected cells is described for the first time in three naturally-infected dogs. Blood smear evaluation indicated that at least 50% of the leukocytes infected with H. canis gamonts contained E. canis morulae. Co-infection of the same host cell demonstrated in this report suggests that infection with one pathogen may permit or enhance invasion or prolonged cellular survival of the other. Copyright © 2014 Elsevier B.V. All rights reserved.

Tick-borne diseases in North Carolina: is "Rickettsia amblyommii" a possible cause of rickettsiosis reported as Rocky Mountain spotted fever?

Science.gov (United States)

Apperson, Charles S; Engber, Barry; Nicholson, William L; Mead, Daniel G; Engel, Jeffrey; Yabsley, Michael J; Dail, Kathy; Johnson, Joey; Watson, D Wesley

2008-10-01

Cases of Rocky Mountain spotted fever (RMSF) in North Carolina have escalated markedly since 2000. In 2005, we identified a county in the Piedmont region with high case numbers of RMSF. We collected ticks and examined them for bacterial pathogens using molecular methods to determine if a novel tick vector or spotted fever group rickettsiae (SFGR) might be emerging. Amblyomma americanum, the lone star tick, comprised 99.6% of 6,502 specimens collected in suburban landscapes. In contrast, Dermacentor variabilis, the American dog tick, a principal vector of Rickettsia rickettsii, comprised < 1% of the ticks collected. Eleven of 25 lone star tick pools tested were infected with "Rickettsia amblyommii," an informally named SFGR. Sera from patients from the same county who were presumptively diagnosed by local physicians with a tick-borne illness were tested by an indirect immunofluorescence antibody (IFA) assay to confirm clinical diagnoses. Three of six patients classified as probable RMSF cases demonstrated a fourfold or greater rise in IgG class antibody titers between paired acute and convalescent sera to "R. amblyommii" antigens, but not to R. rickettsii antigens. White-tailed deer, Odocoileus virginianus, are preferred hosts of lone star ticks. Blood samples collected from hunter-killed deer from the same county were tested by IFA test for antibodies to Ehrlichia chaffeensis and "R. amblyommii." Twenty-eight (87%) of 32 deer were positive for antibodies to E. chaffeensis, but only 1 (3%) of the deer exhibited antibodies to "R. amblyommii," suggesting that deer are not the source of "R. amblyommii" infection for lone star ticks. We propose that some cases of rickettsiosis reported as RMSF may have been caused by "R. amblyommii" transmitted through the bite of A. americanum.

Large tandem accelerators

International Nuclear Information System (INIS)

Jones, C.M.

1976-01-01

The increasing importance of energetic heavy ion beams in the study of atomic physics, nuclear physics, and materials science has partially or wholly motivated the construction of a new generation of tandem accelerators designed to operate at maximum terminal potentials in the range 14 to 30 MV. In addition, a number of older tandem accelerators are now being significantly upgraded to improve their heavy ion performance. Both of these developments have reemphasized the importance of negative heavy ion sources. The new large tandem accelerators are described, and the requirements placed on negative heavy ion source technology by these and other tandem accelerators used for the acceleration of heavy ions are discussed. First, a brief description is given of the large tandem accelerators which have been completed recently, are under construction, or are funded for construction, second, the motivation for construction of these accelerators is discussed, and last, criteria for negative ion sources for use with these accelerators are presented

Mixed Ehrlichia canis, Hepatozoon canis, and presumptive Anaplasma phagocytophilum infection in a dog.

Science.gov (United States)

Mylonakis, Mathio E; Koutinas, Alex F; Baneth, Gad; Polizopoulou, Zoe; Fytianou, Anna

2004-01-01

A 5-month-old, female, mongrel dog was admitted to the Clinic of Companion Animal Medicine, Aristotle University of Thessaloniki, Greece, with depression, anorexia, fever, peripheral lymphadenopathy, splenomegaly, oculonasal discharge, nonregenerative anemia, and mild thrombocytopenia. Cytology of Giemsa-stained buffy coat, bone marrow, and lymph node aspiration smears revealed numerous morulae in mononuclear leukocytes and in neutrophils, and Hepatozoon canis gamonts in neutrophils. The dog was seropositive to Ehrlichia canis (immunofluorescence assay [IFA]) and Hepatozoon canis (ELISA) but not to Anaplasma phagocytophilum (IFA). A nested polymerase chain reaction performed on bone marrow aspirates was positive for E canis. This method was not applied for the detection of A phagocytophilum. Treatment with doxycycline and imidocarb dipropionate resulted in both clinical and parasitologic cure. This is the first reported case of a mixed infection with E canis, H canis, and presumptive A phagocytophilum. The findings emphasize the value of cytology in offering a quick and inexpensive diagnosis in mixed tick-borne infections of dogs.

Serologic evidence of infection with granulocytic ehrlichiae in black bears in Pennsylvania.

Science.gov (United States)

Schultz, Sharon M; Nicholson, William L; Comer, James A; Childs, James E; Humphreys, Jan G

2002-01-01

Serum samples from 381 black bears (Ursus americanus) killed in Pennsylvania (USA) on 24 November 1997 were analyzed for antibodies reactive to the agent of human granulocytic ehrlichiosis (HGE; Ehrlichia sp.) by indirect immunofluorescence assay. Antibody reactivity to HGE antigen was detected in 21% (81/381) of the samples collected. Reactive samples were reported from 56% (14/25) of the counties where bear samples were collected. Endpoint antibody titer ranged from 1:8 to 1:16, 192, with a geometric mean titer of 1:582. There was no significant difference in antibody prevalence between male and female bears (P bears were significantly more likely to have reactive antibodies than juvenile bears (P bear blood clots (n = 181) through nested polymerase chain reaction assays were unsuccessful. Further studies are needed for identification of the pathogen-responsible for induction of HGE-reactive. This is the first description of antibodies reactive to the HGE agent in black bears and suggests these mammals are infected with the agent of HGE or an antigenically related ehrlichial species.

Association between canine leishmaniosis and Ehrlichia canis co-infection: a prospective case-control study.

Science.gov (United States)

Attipa, Charalampos; Solano-Gallego, Laia; Papasouliotis, Kostas; Soutter, Francesca; Morris, David; Helps, Chris; Carver, Scott; Tasker, Séverine

2018-03-20

In the Mediterranean basin, Leishmania infantum is a major cause of disease in dogs, which are frequently co-infected with other vector-borne pathogens (VBP). However, the associations between dogs with clinical leishmaniosis (ClinL) and VBP co-infections have not been studied. We assessed the risk of VBP infections in dogs with ClinL and healthy controls. We conducted a prospective case-control study of dogs with ClinL (positive qPCR and ELISA antibody for L. infantum on peripheral blood) and clinically healthy, ideally breed-, sex- and age-matched, control dogs (negative qPCR and ELISA antibody for L. infantum on peripheral blood) from Paphos, Cyprus. We obtained demographic data and all dogs underwent PCR on EDTA-blood extracted DNA for haemoplasma species, Ehrlichia/Anaplasma spp., Babesia spp., and Hepatozoon spp., with DNA sequencing to identify infecting species. We used logistic regression analysis and structural equation modelling (SEM) to evaluate the risk of VBP infections between ClinL cases and controls. From the 50 enrolled dogs with ClinL, DNA was detected in 24 (48%) for Hepatozoon spp., 14 (28%) for Mycoplasma haemocanis, 6 (12%) for Ehrlichia canis and 2 (4%) for Anaplasma platys. In the 92 enrolled control dogs, DNA was detected in 41 (45%) for Hepatozoon spp., 18 (20%) for M. haemocanis, 1 (1%) for E. canis and 3 (3%) for A. platys. No Babesia spp. or "Candidatus Mycoplasma haematoparvum" DNA was detected in any dog. No statistical differences were found between the ClinL and controls regarding age, sex, breed, lifestyle and use of ectoparasitic prevention. A significant association between ClinL and E. canis infection (OR = 12.4, 95% CI: 1.5-106.0, P = 0.022) was found compared to controls by multivariate logistic regression. This association was confirmed using SEM, which further identified that younger dogs were more likely to be infected with each of Hepatozoon spp. and M. haemocanis, and dogs with Hepatozoon spp. were more likely to

Development of multiplex polymerase chain reaction for detection of Ehrlichia canis, Babesia spp and Hepatozoon canis in canine blood.

Science.gov (United States)

Kledmanee, Kan; Suwanpakdee, Sarin; Krajangwong, Sakranmanee; Chatsiriwech, Jarin; Suksai, Parut; Suwannachat, Pongpun; Sariya, Ladawan; Buddhirongawatr, Ruangrat; Charoonrut, Phingphol; Chaichoun, Kridsada

2009-01-01

A multiplex polymerase chain reaction (PCR) has been developed for simultaneous detection of canine blood parasites, Ehrlichia canis, Babesia spp and Hepatozoon canis, from blood samples in a single reaction. The multiplex PCR primers were specific to E. canis VirB9, Babesia spp 16S rRNA and H. canis 16S rRNA genes. Specificity of the amplicons was confirmed by DNA sequencing. The assay was evaluated using normal canine and infected blood samples, which were detected by microscopic examination. This multiplex PCR offers scope for simultaneous detection of three important canine blood parasites and should be valuable in monitoring parasite infections in dogs and ticks.

A study of reflex tandem accelerator

Energy Technology Data Exchange (ETDEWEB)

Nakajima, Takao; Morinobu, Shunpei; Gono, Yasuyuki; Sagara, Kenji; Sugimitsu, Tsuyoshi; Mitarai, Shiro; Nakamura, Hiroyuki; Ikeda, Nobuo; Morikawa, Tsuneyasu [Kyushu Univ., Fukuoka (Japan). Faculty of Science

1996-12-01

An investigation on `developing research theme and its realizing experimental apparatus` based on the tandem accelerator facility is executed. At a standpoint of recognition on essentiality of preparation, improvement or novel technical development capable of extreme increase in capacity of the tandem accelerator facility to form COE with high uniqueness, proposal of numerous ideas and their investigations and searches were conducted. In this paper, consideration results of `beam reacceleration using tandem accelerator` were shown as follows: (1) Short life unstable nuclei formed by nuclear reaction using tandem acceleration primary beam is ionized to negative and to reaccelerate by using the same tandem accelerator. And (2) by combination of plural electrons with the tandem primary accelerated beam, numbers of charge is reduced to reaccelerate by the tandem. (G.K.)

TANDEM

Data.gov (United States)

Federal Laboratory Consortium — The Tandem Van de Graaff facility provides researchers with beams of more than 40 different types of ions - atoms that have been stripped of their electrons. One of...

Potential measurements in tandem mirrors

International Nuclear Information System (INIS)

Glowienka, J.C.

1985-11-01

The US mirror program has begun conducting experiments with a thermal barrier tandem mirror configuration. This configuration requires a specific axial potential profile and implies measurements of potential for documentation and optimization of the configuration. This report briefly outlines the motivation for the thermal barrier tandem mirror and then outlines the techniques used to document the potential profile in conventional and thermal barrier tandem mirrors. Examples of typical data sets from the world's major tandem mirror experiments, TMX and TMX-U at Lawrence Livermore National Laboratory (LLNL) and Gamma 10 at Tsukuba University in Japan, and the current interpretation of the data are discussed together with plans for the future improvement of measurements of plasma potential

Colorimetric detection of Ehrlichia canis via nucleic acid hybridization in gold nano-colloids.

Science.gov (United States)

Muangchuen, Ajima; Chaumpluk, Piyasak; Suriyasomboon, Annop; Ekgasit, Sanong

2014-08-08

Canine monocytic ehrlichiosis (CME) is a major thick-bone disease of dog caused by Ehrlichia canis. Detection of this causal agent outside the laboratory using conventional methods is not effective enough. Thus an assay for E. canis detection based on the p30 outer membrane protein gene was developed. It was based on the p30 gene amplification using loop-mediated isothermal DNA amplification (LAMP). The primer set specific to six areas within the target gene were designed and tested for their sensitivity and specificity. Detection of DNA signals was based on modulation of gold nanoparticles' surface properties and performing DNA/DNA hybridization using an oligonucleotide probe. Presence of target DNA affected the gold colloid nanoparticles in terms of particle aggregation with a plasmonic color change of the gold colloids from ruby red to purple, visible by the naked eye. All the assay steps were completed within 90 min including DNA extraction without relying on standard laboratory facilities. This method was very specific to target bacteria. Its sensitivity with probe hybridization was sufficient to detect 50 copies of target DNA. This method should provide an alternative choice for point of care control and management of the disease.

STATIONARY DISTRIBUTION OF A TANDEM QUEUE WITH ADDITIONAL FLOWS ON THE STATIONS OF THE TANDEM

Directory of Open Access Journals (Sweden)

V. I. Klimenok

2017-01-01

Full Text Available A tandem queueing system consisting of a finite number of multi-server stations without buffers is analized. The input flow at the first station is a ???????????? (Markovian arrival process. The customers from this flow aim to be served at all stations of the tandem. For any station, besides transit customers proceeding from the previous station, an additional ???????????? flow of new customers arrives at this station directly. Customers from this flow aim to be served at this station and all subsequent stations of the tandem. The service times of customer at the stations are exponentially distributed with the service rate depending of number of the station. The algorithms for culculation of stationary distributions and the loss probabilities associated with the tandem are given.

Tandem accelerator operation and improvements

International Nuclear Information System (INIS)

Yang Bingfan; Zhang Canzhe; Qin Jiuchang; Hu Yueming; Zhang Guilian; Jiang Yongliang; Hou Deyi; Yang Weimin; Yang Zhiren; Su Shengyong; Kan Chaoxin; Liu Dezhong; Wang Liyong; Bao Yiwen; You Qubo; Yang Tao; Zhang Yan; Zhou Lipeng; Chai Shiqin; Wang Meiyan

1998-01-01

The scheduled operation of HI-13 tandem accelerator for various experiments was performed well in 1996 and 1997. The machine running time was 4600 h and 4182 h while the beam time was 3845 h and 3712 h in 1996 and 1997, respectively. The operation of HI-13 tandem accelerator is pretty well. The beam distribution with terminal voltage and the distribution of beam time with ion species are shown out. The development of accelerating tubes for HI-13 tandem is in progress

Tandem accelerators, 1973--1974

International Nuclear Information System (INIS)

Howard, F.T.

1974-01-01

High voltage tandem accelerators are very important instruments in the field of nuclear physics research, especially in the acceleration of heavy ions. This survey identifies 77 tandems installed in 21 countries; of these, 34 are in the United States. Most installations have supplied data sheets identifying their machines and briefly characterizing their research programs. (U.S.)

Detecção molecular de Ehrlichia canis e Babesia canis vogeli em Rhipicephalus sanguineus sensu lato de carrapatos em Cuba

Directory of Open Access Journals (Sweden)

Maylin Gonzalez Navarrete

2016-12-01

Full Text Available Os carrapatos (Acari: Ixodidae são de importância médica e veterinária relevantes em todo o mundo por causa da variedade de agentes patogênicos que podem transmitir. No presente trabalho, foi realizada uma pesquisa para identificar Babesia spp. e Ehrlichia spp. em carrapatos coletados de cães de Cuba. Foram coletados 431 carrapatos de 378 cães, tendo sido identificados como pertencentes às espécies de Ripicephalus sanguineus sensu lato (s. 1. O DNA genômico foi extraído com protocolo usando fenol/clorofórmio. Os carrapatos foram organizados em “pools” e o DNA extraído foi testado pela reação em cadeia da polimerase (nPCR para amplificar 398 pares de bases (pb do DNA ribossômico 16S (rDNA de Ehrlichia canis e PCR para amplificar aproximadamente 560 pb do DNA ribossômico 18S (rDNA. Dos 49 pools testados, 8,16% (n = 4/49 foram positivos para o E. canis por nPCR visando o gene do 16S rDNA e apenas um pool (n = 1/49; 2,04% foi positivo para o gene 18S rDNA para Babesia canis. As quatro sequências obtidas para o fragmento de 16S rDNA foram idênticas entre si e resultaram em 100% de identidade com E. canis de diferentes países. A sequência obtida do gene do 18S rDNA para Babesia spp. apresentou semelhança de 100% com Babesia canis vogeli quando comparada às sequências depositadas no Genbank. Esta foi a primeira detecção molecular desses agentes no carrapato R. sanguineus s. l. em Cuba.

MHD stability of tandem mirrors

International Nuclear Information System (INIS)

Poulsen, P.; Molvik, A.; Shearer, J.

1982-01-01

The TMX-Upgrade experiment was described, and the manner in which various plasma parameters could be affected was discussed. The initial analysis of the MHD stability of the tandem mirror was also discussed, with emphasis on the negative tandem configuration

Brief-stimulus presentations on multiform tandem schedules

OpenAIRE

Reed, Phil

1994-01-01

Three experiments examined the influence of a brief stimulus (a light) on the behavior of food-deprived rats whose lever pressing on tandem schedules comprising components of different schedule types resulted in food presentation. In Experiment 1, either a tandem variable-ratio variable-interval or a tandem variable-interval variable-ratio schedule was used. The variable-interval requirement in the tandem variable-ratio variable-interval schedule was yoked to the time taken to complete the va...

First phylogenetic analysis of Ehrlichia canis in dogs and ticks from Mexico. Preliminary study

Directory of Open Access Journals (Sweden)

Carolina G. Sosa-Gutiérrez

2016-09-01

Full Text Available Objective. Phylogenetic characterization of Ehrlichia canis in dogs naturally infected and ticks, diagnosed by PCR and sequencing of 16SrRNA gene; compare different isolates found in American countries. Materials and methods. Were collected Blood samples from 139 dogs with suggestive clinical manifestations of this disease and they were infested with ticks; part of 16SrRNA gene was sequenced and aligned, with 17 sequences reported in American countries. Two phylogenetic trees were constructed using the Maximum likelihood method, and Maximum parsimony. Results. They were positive to E. canis 25/139 (18.0% dogs and 29/139 (20.9% ticks. The clinical manifestations presented were fever, fatigue, depression and vomiting. Rhipicephalus sanguineus Dermacentor variabilis and Haemaphysalis leporis-palustris ticks were positive for E. canis. Phylogenetic analysis showed that the sequences of dogs and ticks in Mexico form a third group diverging of sequences from South America and USA. Conclusions. This is the first phylogenetic analysis of E. canis in Mexico. There are differences in the sequences of Mexico with those reported in South America and USA. This research lays the foundation for further study of genetic variability.

Mouse infection models for space flight immunology

Science.gov (United States)

Chapes, Stephen Keith; Ganta, Roman Reddy; Chapers, S. K. (Principal Investigator)

2005-01-01

Several immunological processes can be affected by space flight. However, there is little evidence to suggest that flight-induced immunological deficits lead to illness. Therefore, one of our goals has been to define models to examine host resistance during space flight. Our working hypothesis is that space flight crews will come from a heterogeneous population; the immune response gene make-up will be quite varied. It is unknown how much the immune response gene variation contributes to the potential threat from infectious organisms, allergic responses or other long term health problems (e.g. cancer). This article details recent efforts of the Kansas State University gravitational immunology group to assess how population heterogeneity impacts host health, either in laboratory experimental situations and/or using the skeletal unloading model of space-flight stress. This paper details our use of several mouse strains with several different genotypes. In particular, mice with varying MHCII allotypes and mice on the C57BL background with different genetic defects have been particularly useful tools with which to study infections by Staphylococcus aureus, Salmonella typhimurium, Pasteurella pneumotropica and Ehrlichia chaffeensis. We propose that some of these experimental challenge models will be useful to assess the effects of space flight on host resistance to infection.

In situ detection of tandem DNA repeat length

Energy Technology Data Exchange (ETDEWEB)

Yaar, R.; Szafranski, P.; Cantor, C.R.; Smith, C.L. [Boston Univ., MA (United States)

1996-11-01

A simple method for scoring short tandem DNA repeats is presented. An oligonucleotide target, containing tandem repeats embedded in a unique sequence, was hybridized to a set of complementary probes, containing tandem repeats of known lengths. Single-stranded loop structures formed on duplexes containing a mismatched (different) number of tandem repeats. No loop structure formed on duplexes containing a matched (identical) number of tandem repeats. The matched and mismatched loop structures were enzymatically distinguished and differentially labeled by treatment with S1 nuclease and the Klenow fragment of DNA polymerase. 7 refs., 4 figs.

JAERI 20 MV tandem accelerator

International Nuclear Information System (INIS)

Tsukada, Kineo; Harada, Kichinosuke

1977-01-01

Accelerators have been developed as the experimental apparatuses for the studies on nuclei and elementary particles. One direction of the development is the acceleration of protons and electrons to more and more high energy, and another direction is the acceleration of heavy ions up to uranium to several MeV up to several hundreds MeV. However recently, accelerators are used as the useful tools for the studies in wider fields. There are electrostatic acceleration and high frequency acceleration in ion acceleration, and at present, super-large accelerators are high frequency acceleration type. In Japan Atomic Energy Research Institute, it was decided in 1975 to construct an electrostatic accelerator of tandem type in order to accelerate heavy ions. In case of the electrostatic acceleration, the construction is relatively simple, the acceleration of heavy ions is easy, the property of the ion beam is very good, and the energy is stable. Especially, the tandem type is convenient for obtaining high energy. The tandem accelerator of 20 MV terminal voltage was ordered from the National Electrostatics Corp., USA, and is expected to be completed in 1978. The significance of heavy ion acceleration in the development and research of atomic energy, tandem van de Graaff accelerators, the JAERI 20MV tandem accelerator, and the research project with this accelerator are described. (Kako, I.)

Tandemly Arrayed Genes in Vertebrate Genomes

Directory of Open Access Journals (Sweden)

Deng Pan

2008-01-01

Full Text Available Tandemly arrayed genes (TAGs are duplicated genes that are linked as neighbors on a chromosome, many of which have important physiological and biochemical functions. Here we performed a survey of these genes in 11 available vertebrate genomes. TAGs account for an average of about 14% of all genes in these vertebrate genomes, and about 25% of all duplications. The majority of TAGs (72–94% have parallel transcription orientation (i.e., they are encoded on the same strand in contrast to the genome, which has about 50% of its genes in parallel transcription orientation. The majority of tandem arrays have only two members. In all species, the proportion of genes that belong to TAGs tends to be higher in large gene families than in small ones; together with our recent finding that tandem duplication played a more important role than retroposition in large families, this fact suggests that among all types of duplication mechanisms, tandem duplication is the predominant mechanism of duplication, especially in large families. Finally, several species have a higher proportion of large tandem arrays that are species-specific than random expectation.

Molecular and serological detection of Ehrlichia canis and Babesia vogeli in dogs in Colombia.

Science.gov (United States)

Vargas-Hernández, G; André, M R; Faria, J L M; Munhoz, T D; Hernandez-Rodriguez, M; Machado, R Z; Tinucci-Costa, M

2012-05-25

Ehrlichiosis and babesiosis are tick-borne diseases, caused mainly by Ehrlichia canis and Babesia canis, respectively, with a worldwide occurrence in dogs, whose main vector is the brown-dog tick, Rhipicephalus sanguineus. The present work aimed to detect the presence of E. canis and Babesia sp. in 91 dog blood samples in Colombia, by molecular and serological techniques. We also performed sequence alignment to indicate the identity of the parasite species infecting these animals. The present work shows the first molecular detection of E. canis and B. vogeli in dogs from Colombia. Immunoglobulin-G (IgG) antibodies to E. canis and Babesia vogeli were found in 75 (82.4%) and 47 (51.6%) sampled dogs, respectively. Thirty-seven (40.6%) and 5 (5.5%) dogs were positive in PCR for E. canis and Babesia sp., respectively. After sequencing, amplicons showed 99% of identity with isolates of E. canis and B. vogeli. The phylogenetic trees based on 16S rRNA-Anaplasmataceae sequences and 18S rRNA-piroplasmid sequences supported the identity of the found E. canis and B. vogeli DNAs, respectively. The present work shows the first molecular detection of E. canis and B. vogeli in dogs in Colombia. Copyright © 2011 Elsevier B.V. All rights reserved.

Tandems as injectors for synchrotrons

International Nuclear Information System (INIS)

Ruggiero, A.G.

1993-01-01

This is a review on the use of tandem electrostatic accelerators for injection and fitting of synchrotrons to accelerate intense beams of heavy ions to relativistic energies. The paper emphasizes the need of operating the tandems in pulsed mode for this application. It has been experimentally demonstrated that at present this type of accelerator still provides the most reliable and best performance. (orig.)

Serological cross-reactivity of Trypanosoma cruzi, Ehrlichia canis, Toxoplasma gondii, Neospora caninum and Babesia canis to Leishmania infantum chagasi tests in dogs

Directory of Open Access Journals (Sweden)

Maurício Franco Zanette

2014-01-01

Full Text Available Introduction: The aim of this study was to evaluate the serological cross-reactivity between Leishmania sp. and other canine pathogens. Methods: Positive serum samples for Ehrlichia canis, Babesia canis, Toxoplasma gondii, Neospora caninum and Trypanosoma cruzi were tested using three serological methods enzyme linked immunosorbent assay (ELISA, indirect immunofluorescent antibody test (IFAT and Kalazar Detect™, for canine visceral leishmaniasis. Results: Of the 57 dog samples tested, 24 (42.1% tested positive using one of the three serological methods: 10/57 (17.5% for ELISA, 11/57 (19.3% for IFAT and 3/57 (5.3% for Kalazar Detect™. Conclusions: Our results demonstrated that the presence of other infectious agents may lead to cross-reactivity on leishmaniasis serological tests.

Actualization of the Tandem-E N Accelerator of the Nuclear Centre of Mexico; Actualizacion del Acelerador Tandem-EN del Centro Nuclear

Energy Technology Data Exchange (ETDEWEB)

Villasenor S, P.; Aguilera R, E.; Aspiazu F, J.; Fernandez A, J.; Fernandez B, M.; Garcia R, B.; Lopez M, J.; Martinez Q, E.; Mendez G, B.; Moreno B, E.; Murillo O, G.; Policroniades R, R.; Ramirez T, J.; Reynoso V, R.; Varela G, A.; Vega C, J. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2004-07-01

In this work, the activities are described carried out to change the tubes accelerators and original resistances of the accelerator Tandem-E N of the Nuclear Center, for tubes DOWLISH and resistances again design, both donated ones for ORNL. This way same, the problem is described that imply this changes, and like it was solved by the personnel of the laboratory, without having to appeal to external services, what there is redounded in a considerable increment in the costs. In form preliminary the improvements are described observed after the rehabilitation of the Accelerator. (Author)

Molecular detection of Dirofilaria immitis, Hepatozoon canis, Babesia spp., Anaplasma platys and Ehrlichia canis in dogs on Costa Rica.

Science.gov (United States)

Wei, Lanjing; Kelly, Patrick; Ackerson, Kate; El-Mahallawy, Heba S; Kaltenboeck, Bernhard; Wang, Chengming

2014-03-01

Although vector-borne diseases are important causes of morbidity and mortality in dogs in tropical areas, there is little information on these conditions in Costa Rica. In PCRs of blood from dogs in Costa Rica, we did not detect DNAs of Rickettsia (R.) felis and Coxiella (C.) burnetii but we did find evidence of infection with Dirofilaria (D.) immitis (9/40, 22.5%), Hepatozoon (H.) canis (15/40, 37.5%), Babesia spp. (10/40, 25%; 2 with B. gibsoni and 8 with B. vogeli), Anaplasma (A.) platys (3/40, 7.5%) and Ehrlichia (E.) canis (20/40, 50%). Nine dogs (22.5%) were free of any vector-borne pathogens while 14 (35%) were infected with a single pathogen, 11 (27.5%) with two, 4 (10%) with three, 1 (2.5%) with four, and 1 (2.5%) with five pathogens. Dogs in Costa Rica are commonly infected with vector-borne agents.

Parametric studies of tandem mirror reactors

International Nuclear Information System (INIS)

Carlson, G.A.; Boghosian, B.M.; Fink, J.H.; Myall, J.O.; Neef, W.S. Jr.

1979-01-01

This report, along with its companion, An Improved Tandem Mirror Reactor, discusses the recent progress and present status of our tandem mirror reactor studies. This report presents the detailed results of parametric studies up to, but not including, the very new ideas involving thermal barriers

Edge diagnostics for tandem mirror machines

International Nuclear Information System (INIS)

Allen, S.L.

1984-01-01

The edge plasma in a tandem mirror machine shields the plasma core from cold neutral gas and impurities. A variety of diagnostics are used to measure the fueling, shielding, and confinement of the edge plasma in both the end plug and central cell regions. Fast ion gauges and residual gas analyzers measure the gas pressure and composition outside of the plasma. An array of Langmuir probes is used to measure the electron density and temperature. Extreme ultraviolet (euv) and visible spectroscopy are used to measure both the impurity and deuterium densities and to estimate the shielding factor for the core plasma. The linear geometry of a tandem mirror also allows direct measurements of the edge plasma by sampling the ions and electrons lost but the ends of the machine. Representative data obtained by these diagnostics during operation of the Tandem Mirror Experiment (TMX) and Tandem Mirror Experiment-Upgrade (TMX-U) experiments are presented. Diagnostics that are currently being developed to diagnose the edge plasma are also discussed

Introduction to tandem mirror physics

International Nuclear Information System (INIS)

Kesner, J.; Gerver, M.J.; Lane, B.G.; McVey, B.D.; Catto, P.J.; D'Ippolito, D.A.; Myra, J.R.

1983-09-01

This monograph, prepared jointly by the MIT Plasma Fusion Center Mirror Fusion group and SAI, Boulder, Colorado, presents a review of the development of mirror fusion theory from its conception some thirty years ago to the present. Pertinent historic experiments and their contribution are discussed to set the stage for a detailed analysis of current experiments and the problems which remain to be solved in bringing tandem mirror magnetic confinement fusion to fruition. In particular, Chapter III discusses in detail the equilibrium and stability questions which must be dealt with before tandem mirror reactors become feasible, while Chapters IV and V discuss some of the current machines and those under construction which will help to resolve critical issues in both physics and engineering whose solutions are necessary to the commercialization of tandem mirror fusion

North-American MP Tandem accelerators

International Nuclear Information System (INIS)

Wegner, H.E.; Thieberger, P.

1977-01-01

There are six North-American MP Tandem accelerators: Yale; Minnesota; Chalk River; Rochester; and two at Brookhaven. The current status and operating characteristics of these six tandem accelerators are discussed. Upgrade and special improvements of the different machines is reviewed and new developments since the last Electrostatic Conference are discussed in detail. The overall operating characteristics of the different machines during the last year of operation are compared

Actualization of the Tandem-E N Accelerator of the Nuclear Centre of Mexico

International Nuclear Information System (INIS)

Villasenor S, P.; Aguilera R, E.; Aspiazu F, J.; Fernandez A, J.; Fernandez B, M.; Garcia R, B.; Lopez M, J.; Martinez Q, E.; Mendez G, B.; Moreno B, E.; Murillo O, G.; Policroniades R, R.; Ramirez T, J.; Reynoso V, R.; Varela G, A.; Vega C, J.

2004-01-01

In this work, the activities are described carried out to change the tubes accelerators and original resistances of the accelerator Tandem-E N of the Nuclear Center, for tubes DOWLISH and resistances again design, both donated ones for ORNL. This way same, the problem is described that imply this changes, and like it was solved by the personnel of the laboratory, without having to appeal to external services, what there is redounded in a considerable increment in the costs. In form preliminary the improvements are described observed after the rehabilitation of the Accelerator. (Author)

Tandem Translation Classroom: A Case Study

Science.gov (United States)

Kim, Dohun; Koh, Taejin

2018-01-01

The transition to student-centred learning, advances in teleconferencing tools, and active international student exchange programmes have stimulated tandem learning in many parts of the world. This pedagogical model is based on a mutual language exchange between tandem partners, where each student is a native speaker in the language the…

A solution process for inverted tandem solar cells

DEFF Research Database (Denmark)

Larsen-Olsen, Thue Trofod; Bundgaard, Eva; Sylvester-Hvid, Kristian O.

2011-01-01

Tandem solar cells with normal and inverted device geometries were prepared by a solution process. Both device types were based on the use of zinc(II)oxide as the electron transporting layer (ETL). The hole transporting layer (HTL) was either PEDOT:PSS for normal geometry tandem solar cells...... or vanadium(V)oxide in the case of inverted tandem cells. It was found that the inverted tandem solar cells performed comparable or better than the normal geometry devices, showing that the connection structure of vanadium(V)oxide, Ag nanoparticles and zinc(II)oxide functions both as a good recombination...... layer, ensuring serial connection, and as a solvent barrier, protecting the first photoactive layer from processing of the second layer. This successfully demonstrates a tandem solar cell fabrication process fully compatible with state-of-the-art solution based automated production procedures....

Thermodynamic characterization of tandem mismatches found in naturally occurring RNA

Science.gov (United States)

Christiansen, Martha E.; Znosko, Brent M.

2009-01-01

Although all sequence symmetric tandem mismatches and some sequence asymmetric tandem mismatches have been thermodynamically characterized and a model has been proposed to predict the stability of previously unmeasured sequence asymmetric tandem mismatches [Christiansen,M.E. and Znosko,B.M. (2008) Biochemistry, 47, 4329–4336], experimental thermodynamic data for frequently occurring tandem mismatches is lacking. Since experimental data is preferred over a predictive model, the thermodynamic parameters for 25 frequently occurring tandem mismatches were determined. These new experimental values, on average, are 1.0 kcal/mol different from the values predicted for these mismatches using the previous model. The data for the sequence asymmetric tandem mismatches reported here were then combined with the data for 72 sequence asymmetric tandem mismatches that were published previously, and the parameters used to predict the thermodynamics of previously unmeasured sequence asymmetric tandem mismatches were updated. The average absolute difference between the measured values and the values predicted using these updated parameters is 0.5 kcal/mol. This updated model improves the prediction for tandem mismatches that were predicted rather poorly by the previous model. This new experimental data and updated predictive model allow for more accurate calculations of the free energy of RNA duplexes containing tandem mismatches, and, furthermore, should allow for improved prediction of secondary structure from sequence. PMID:19509311

Neospora caninum and Ehrlichia canis co-infection in a dog with meningoencephalitis.

Science.gov (United States)

Aroch, Itamar; Baneth, Gad; Salant, Harold; Nachum-Biala, Yaarit; Berkowitz, Asaf; Shamir, Merav; Chai, Orit

2018-06-01

An 8-year-old mixed-breed dog was presented for acute, progressive weakness and ataxia, inappetence, and weight loss. The patient was mentally normal, but nonambulatory, with a right head tilt, right positional ventral strabismus, and slight head tremors. A neurologic lesion was localized to the cerebellum and right brainstem. Cerebrospinal fluid (CSF) analysis showed a markedly increased protein concentration and mixed pleocytosis, with eosinophil predominance (44%), intracytoplasmic inclusions within eosinophils, consistent with Ehrlichia canis (E canis) morulae, and Toxoplasma gondii (T gondii) or Neospora caninum (N caninum) tachyzoites within eosinophils and monocytes. A serum indirect immunofluorescent antibody test was positive for N caninum (titer 1:12 800) and negative for T gondii. Both blood and CSF PCR results were N caninum- and E canis-positive and T gondii- and Anaplasma phagocytophilum-negative, and blood PCR, but not CSF PCR, was Hepatozoon canis-positive. The dog was treated for 30 days with clindamycin, sulfamethoxazole-trimethoprim, doxycycline, prednisone, and cephalosporin, but did not improve neurologically, and was euthanized. Brain histopathology showed moderate multifocal, subacute meningoencephalitis with necrosis and gliosis. The neurologic disease was mostly attributed to central nervous system (CNS) neosporosis, with the possible contribution of ehrlichiosis, which was likely a manifestation of blood-brain barrier disruption. Hepatozoonosis was probably a result or cause of underlying immunosuppression. To our knowledge, this is the first report of CNSN caninum and E canis co-infection detected by both CSF PCR and cytology and E canis morulae identified within CSF eosinophils. © 2018 American Society for Veterinary Clinical Pathology.

The Kyoto University tandem upgrading project

International Nuclear Information System (INIS)

Nakamura, Masanobu; Shimoura, Susumu; Takimoto, Kiyohiko; Sakaguchi, Harutaka; Kobayashi, Shinsaku

1988-01-01

A brief description on the Kyoto University tandem upgrading project. The project consists of replacing the old 5 MV tandem Van de Graaff by an 8UDH pelletron. The old pressure vessel and beam lines are used again without significant modification. The project is planned to be completed at the end of 1989. (orig.)

Design of tandem mirror reactors with thermal barriers

International Nuclear Information System (INIS)

Carlson, G.A.

1980-01-01

End-plug technologies for tandem mirror reactors include high-field superconducting magnets, neutral beam injectors, and gyrotrons for electron cyclotron resonant heating (ECRH). In addition to their normal use for sustenance of the end-plug plasmas, neutral beam injectors are used for ''pumping'' trapped ions from the thermal barrier regions by charge exchange. An extra function of the axially directed pump beams is the removal of thermalized alpha particles from the reactor. The principles of tandem mirror operation with thermal barriers will be demonstrated in the upgrade of the Tandem Mirror Experiment (TMX-U) in 1981 and the tandem configuration of the Mirror fusion Test Facility (MFTF-B) in 1984

Argonne tandem as injector to a superconducting linac

International Nuclear Information System (INIS)

Yntema, J.L.; Den Hartog, P.K.; Henning, W.; Kutschera, W.

1980-01-01

The Argonne Tandem uses Pelletron chains, NEC accelerator tubes, and a dual closed-corona system. Its main function is to be an injector for a superconducting linear accelerator. As long as the transverse and longitudinal emittances are within the acceptance of the linac, the output beam quality of the tandem-linac system is essentially determined by the tandem. The sensitivity of the linac to the longitudinal emittance ΔEΔt of the incident beam makes the output beam quality dependent on the negative-ion velocity distribution in the source, transit-time effects in the tandem, molecular-beam dissociation, and stripper-foil uniformity. This paper discusses these beam-degrading effects

Molecular epidemiology of parasitic protozoa and Ehrlichia canis in wildlife in Madrid (central Spain).

Science.gov (United States)

Criado-Fornelio, Angel; Martín-Pérez, T; Verdú-Expósito, C; Reinoso-Ortiz, S A; Pérez-Serrano, J

2018-07-01

Wildlife species are involved in the transmission of diverse pathogens. This study aimed to monitor raccoons (Procyon lotor), American minks (Neovison vison), and red foxes (Vulpes vulpes) as potential reservoirs in central Spain. Specifically, 200 spleen and fecal samples (from 194 raccoons, 3 minks, and 3 foxes) were analyzed molecularly by PCR/qPCR and sequencing for the presence of piroplasmids, Hepatozoon spp., Toxoplasma gondii, and Ehrlichia canis infections in the Community of Madrid (Spain). Biological samples were obtained in the years 2014, 2015, and 2016. No pathogen DNA was found in fecal samples. In contrast, analysis of raccoon spleen samples revealed that Toxoplasma was the most prevalent pathogen (prevalence 3.6 ± 2.6%), followed by Hepatozoon canis and E. canis (each with a prevalence of 2.57 ± 2.2%). Hepatozoon canis was also diagnosed in all three of the analyzed foxes. Analysis of yearly prevalence showed that tick-borne pathogens were less frequent in raccoon in 2015, a dry and warm year compared both to 2014 and 2016. These data suggest that fecal PCR assays are unsuitable for detection of DNA of non-erythrocytic pathogens. Furthermore, they demonstrate that the raccoon (an invasive species often living in proximity to domestic areas) and the red fox are putative reservoirs for pathogenic organisms in the Community of Madrid.

Packet models revisited: tandem and priority systems

NARCIS (Netherlands)

M.R.H. Mandjes (Michel)

2004-01-01

textabstractWe examine two extensions of traditional single-node packet-scale queueing models: tandem networks and (strict) priority systems. Two generic input processes are considered: periodic and Poisson arrivals. For the two-node tandem, an exact expression is derived for the joint distribution

Injector of the Utrecht EN tandem

Energy Technology Data Exchange (ETDEWEB)

Borg, K. van der; Haas, A.P. de; Hoogenboom, A.M.; Strasters, B.A.; Vermeer, A.; Zwol, N.A. van (Rijksuniversiteit Utrecht (Netherlands). Fysisch Lab.)

1984-02-15

An injector has been built to obtain improved beam transmission through the EN tandem. The injector has been provided with a 90/sup 0/ analysing magnet, m/..delta..m=300, and 130 kV preacceleration. Beam optics calculations have been made for the injector and tandem. The injector has been equipped with a fiber optics control and data acquisition system.

Device operation of organic tandem solar cells

NARCIS (Netherlands)

Hadipour, A.; de Boer, B.; Blom, P. W. M.

2008-01-01

A generalized methodology is developed to obtain the current-voltage characteristic of polymer tandem solar cells by knowing the electrical performance of both sub cells. We demonstrate that the electrical characteristics of polymer tandem solar cells are correctly predicted for both the series and

The impact of genome triplication on tandem gene evolution in Brassica rapa

Directory of Open Access Journals (Sweden)

Lu eFang

2012-11-01

Full Text Available Whole genome duplication (WGD and tandem duplication (TD are both important modes of gene expansion. However, how whole genome duplication influences tandemly duplicated genes is not well studied. We used Brassica rapa, which has undergone an additional genome triplication (WGT and shares a common ancestor with Arabidopsis thaliana, Arabidopsis lyrata and Thellungiella parvula, to investigate the impact of genome triplication on tandem gene evolution. We identified 2,137, 1,569, 1,751 and 1,135 tandem gene arrays in B. rapa, A. thaliana, A. lyrata and T. parvula respectively. Among them, 414 conserved tandem arrays are shared by the 3 species without WGT, which were also considered as existing in the diploid ancestor of B. rapa. Thus, after genome triplication, B. rapa should have 1,242 tandem arrays according to the 414 conserved tandems. Here, we found 400 out of the 414 tandems had at least one syntenic ortholog in the genome of B. rapa. Furthermore, 294 out of the 400 shared syntenic orthologs maintain tandem arrays (more than one gene for each syntenic hit in B. rapa. For the 294 tandem arrays, we obtained 426 copies of syntenic paralogous tandems in the triplicated genome of B. rapa. In this study, we demonstrated that tandem arrays in B. rapa were dramatically fractionated after WGT when compared either to non-tandem genes in the B. rapa genome or to the tandem arrays in closely related species that have not experienced a recent whole-genome polyploidization event.

Thirty years of physics at the Bucharest tandem accelerator

International Nuclear Information System (INIS)

Dobrescu, S.; Marinescu, L.; Dumitru, G.; Cata-Danil, Gh.

2003-01-01

The main parameters of the Bucharest tandem accelerator, as well as the main milestones of its history since March 1973 when it was commissioned are shortly presented. A general presentation of the main basic and applied physics research so far undertaken at the tandem is given, ending with some ideas related with the future perspectives of the tandem. (authors)

Tandem mirror reactor

International Nuclear Information System (INIS)

Moir, R.W.; Barr, W.L.; Carlson, G.A.

1977-01-01

A parametric analysis and a preliminary conceptual design for a 1000 MWe Tandem Mirror Reactor (TMR) are described. The concept is sufficiently attractive to encourage further work, both for a pure fusion TMR and a low technology TMR Fusion-Fission Hybrid

Molecular epidemiology of Anaplasma platys, Ehrlichia canis and Babesia vogeli in stray dogs in Paraná, Brazil

Directory of Open Access Journals (Sweden)

Claudia M. Ribeiro

Full Text Available ABSTRACT: Hemoparasitic infections are tick-borne diseases, which affect animals and humans. Considering the importance of canine hemoparasitic infections in veterinary clinics, this study aimed to determine the occurrence of Anaplasma platys, Ehrlichia canis and Babesia vogeli in blood samples from 182 dogs not domiciled in the city of Pato Branco, southwestern region of Paraná State, Brazil, using polymerase chain reaction (PCR. The prevalence of A. platys and B. vogeli was 32.9% and 10.9% respectively, and A. platys infection prevailed (p<0.001. The number of dogs positive for A. platys was larger in Winter (p<0.05. All blood samples were negative for E. canis. In the dogs, infestation by Amblyomma cajennense predominated over that by Rhipicephalus sanguineus (p<0.001; but there was no significant association between PCR and the variables presence of ticks, sex and age. Dogs infected by A. platys and B. vogeli showed thrombocytopenia, lymphopenia and leukocytosis; but there was no correlation between such hematological changes and infection by hemoparasites. This appears to be the first molecular study that demonstrates the existence of A. platys and B. vogeli in dogs from the southwestern region of Paraná.

Tandem catalysis: a new approach to polymers.

Science.gov (United States)

Robert, Carine; Thomas, Christophe M

2013-12-21

The creation of polymers by tandem catalysis represents an exciting frontier in materials science. Tandem catalysis is one of the strategies used by Nature for building macromolecules. Living organisms generally synthesize macromolecules by in vivo enzyme-catalyzed chain growth polymerization reactions using activated monomers that have been formed within cells during complex metabolic processes. However, these biological processes rely on highly complex biocatalysts, thus limiting their industrial applications. In order to obtain polymers by tandem catalysis, homogeneous and enzyme catalysts have played a leading role in the last two decades. In the following feature article, we will describe selected published efforts to achieve these research goals.

Feasibility study on tandem fuel cycle

International Nuclear Information System (INIS)

Han, P.S.; Suh, I.S.; Rim, C.S.; Kim, B.K.; Suh, K.S.; Ro, S.K.; Juhn, P.I.; Kim, S.Y.

1983-01-01

The objective of this feasibility study is to review and assess the current state of technology concerning the tandem fuel cycle. Based on the results from this study, a long-term development plan suitable for Korea has been proposed for this cycle, i.e., the PWR → CANDU tandem fuel cycle which used plutonium and uranium, recovered from spent PWR fuel by co-processing, as fuel material for CANDU reactors. (Author)

Tandem mass spectrometry at low kinetic energy

International Nuclear Information System (INIS)

Cooks, R.G.; Hand, O.W.

1987-01-01

Recent progress in mass spectrometry, as applied to molecular analysis, is reviewed with emphasis on tandem mass spectrometry. Tandem instruments use multiple analyzers (sector magnets, quadrupole mass filters and time-of-flight devices) to select particular molecules in ionic form, react them in the gas-phase and then record the mass, momenta or kinetic energies of their products. The capabilities of tandem mass spectrometry for identification of individual molecules or particular classes of compounds in complex mixtures are illustrated. Several different types of experiments can be run using a tandem mass spectrometer; all share the feature of sifting the molecular mixture being analyzed on the basis of chemical properties expressed in terms of ionic mass, kinetic energy or charge state. Applications of mass spectrometry to biological problems often depend upon desorption methods of ionization in which samples are bombarded with particle beams. Evaporation of preformed charged species from the condensed phase into the vacuum is a particularly effective method of ionization. It is suggested that the use of accelerator mass spectrometers be extended to include problems of molecular analysis. In such experiments, low energy tandem mass spectrometry conducted in the eV or keV range of energies, would be followed by further characterization of the production ion beam using high selective MeV collision processes

Intraoperative bleeding in dogs from Grenada seroreactive to Anaplasma platys and Ehrlichia canis.

Science.gov (United States)

Lanza-Perea, M; Zieger, U; Qurollo, B A; Hegarty, B C; Pultorak, E L; Kumthekar, S; Bruhl-Day, R; Breitschwerdt, E B

2014-01-01

Frequent exposure of Grenadian dogs to Rhipicephalus sanguineus results in Anaplasma platys, and Ehrlichia canis seroreactivity. During elective surgeries, substantial intraoperative hemorrhage occurs in some seroreactive dogs. To assess hemostatic parameters and bleeding tendencies as well as prevalence of PCR positivity in apparently healthy A. platys and E. canis seroreactive and seronegative free-roaming dogs from Grenada. Forty-seven elective surgery dogs allocated to 4 groups: Seronegative control (n = 12), A. platys (n = 10), E. canis (n = 14) and A. platys, and E. canis (n = 11) seroreactive. Preoperatively, hemostasis was assessed by platelet count, prothrombin time, activated partial thromboplastin time, and buccal mucosal bleeding time. Intra- and postoperative bleeding scores were subjectively assigned. Blood, spleen, bone marrow, and lymph node aspirates were tested by PCR. Bleeding scores in dogs coseroreactive for A. platys and E. canis were higher (P = .015) than those of seronegative dogs. A. platys DNA was amplified from 7/21 (33%) A. platys seroreactive dogs and from 1 E. canis seroreactive dog; E. canis DNA was amplified from 21/25 (84%) E. canis seroreactive dogs. E. canis DNA was amplified most often from blood, whereas A. platys DNA was amplified most often from bone marrow. Apparently healthy, free-roaming dogs coseropositive for A. platys and E. canis may have increased intraoperative bleeding tendencies despite normal hemostatic parameters. Future investigations should explore the potential for vascular injury as a cause for bleeding in these dogs. Improved tick control is needed for dogs in Grenada. Copyright © 2014 by the American College of Veterinary Internal Medicine.

"Nanocrystal bilayer for tandem catalysis"

Energy Technology Data Exchange (ETDEWEB)

Yamada, Yusuke; Tsung, Chia Kuang; Huang, Wenyu; Huo, Ziyang; E.Habas, Susan E; Soejima, Tetsuro; Aliaga, Cesar E; Samorjai, Gabor A; Yang, Peidong

2011-01-24

Supported catalysts are widely used in industry and can be optimized by tuning the composition and interface of the metal nanoparticles and oxide supports. Rational design of metal-metal oxide interfaces in nanostructured catalysts is critical to achieve better reaction activities and selectivities. We introduce here a new class of nanocrystal tandem catalysts that have multiple metal-metal oxide interfaces for the catalysis of sequential reactions. We utilized a nanocrystal bilayer structure formed by assembling platinum and cerium oxide nanocube monolayers of less than 10 nm on a silica substrate. The two distinct metal-metal oxide interfaces, CeO2-Pt and Pt-SiO2, can be used to catalyse two distinct sequential reactions. The CeO2-Pt interface catalysed methanol decomposition to produce CO and H2, which were subsequently used for ethylene hydroformylation catalysed by the nearby Pt-SiO2 interface. Consequently, propanal was produced selectively from methanol and ethylene on the nanocrystal bilayer tandem catalyst. This new concept of nanocrystal tandem catalysis represents a powerful approach towards designing high-performance, multifunctional nanostructured catalysts

TASKA - Tandem Spiegelmaschine Karlsruhe. Vol. 1

International Nuclear Information System (INIS)

1982-06-01

TASKA (Tandem Spiegelmaschine Karlsruhe) is a near term engineering test facility based on a tandem mirror concept with thermal barriers. The main objectives of this study were to develop a preconceptual design of a facility that could provide engineering design information for a Demonstration Fusion Power Reactor. Thus TASKA has to serve as testbed for technologies of plasma engineering, superconducting magnets, materials, plasma heating, breeding and test blankets, tritium technology, and remote handling. (orig.) [de

TASKA - Tandem Spiegelmaschine Karlsruhe. Vol. 2

International Nuclear Information System (INIS)

1982-06-01

TASKA (Tandem Spiegelmaschine Karlsruhe) is a near term engineering test facility based on a tandem mirror concept with thermal barriers. The main objectives of this study were to develop a preconceptual design of a facility that could provide engineering design information for a Demonstration Fusion Power Reactor. Thus TASKA has to serve as testbed for technologies of plasma engineering, superconducting magnets, materials, plasma heating, breeding and test blankets, tritium technology, and remote handling. (orig.) [de

Tandem Mirror Reactor Systems Code (Version I)

International Nuclear Information System (INIS)

Reid, R.L.; Finn, P.A.; Gohar, M.Y.

1985-09-01

A computer code was developed to model a Tandem Mirror Reactor. Ths is the first Tandem Mirror Reactor model to couple, in detail, the highly linked physics, magnetics, and neutronic analysis into a single code. This report describes the code architecture, provides a summary description of the modules comprising the code, and includes an example execution of the Tandem Mirror Reactor Systems Code. Results from this code for two sensitivity studies are also included. These studies are: (1) to determine the impact of center cell plasma radius, length, and ion temperature on reactor cost and performance at constant fusion power; and (2) to determine the impact of reactor power level on cost

Monolithic Parallel Tandem Organic Photovoltaic Cell with Transparent Carbon Nanotube Interlayer

Science.gov (United States)

Tanaka, S.; Mielczarek, K.; Ovalle-Robles, R.; Wang, B.; Hsu, D.; Zakhidov, A. A.

2009-01-01

We demonstrate an organic photovoltaic cell with a monolithic tandem structure in parallel connection. Transparent multiwalled carbon nanotube sheets are used as an interlayer anode electrode for this parallel tandem. The characteristics of front and back cells are measured independently. The short circuit current density of the parallel tandem cell is larger than the currents of each individual cell. The wavelength dependence of photocurrent for the parallel tandem cell shows the superposition spectrum of the two spectral sensitivities of the front and back cells. The monolithic three-electrode photovoltaic cell indeed operates as a parallel tandem with improved efficiency.

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2007. Operation, utilization and technical development of JRR-3, JRR-4, NSRR and tandem accelerator

International Nuclear Information System (INIS)

Miyazaki, Osamu; Awa, Yasuaki; Isaka, Koji; Kutsukake, Kenichi; Komeda, Masao; Shibata, Ko; Hiyama, Kazuhisa; Suzuki, Mayu; Sone, Takuya; Ohuchi, Tomoaki; Terakado, Yuichi; Sataka, Masao

2009-06-01

The Department of Research Reactors and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3(Japan Research Reactor-3), JRR-4(Japan Research Reactor-4), NSRR(Nuclear Safety Research Reactor) and Tandem Accelerator. This annual report describes a summary of activities of services and technical developments carried out in the period between April 1, 2007 and March 31, 2008. The activities were categorized into five service/development fields: (1) Operation and maintenance of research reactors and tandem accelerator. (2) Utilization of research reactors and tandem accelerator. (3) Upgrading of utilization techniques of research reactors and tandem accelerator. (4) Safety administration for research reactors and tandem accelerator. (5) International cooperation. Also contained are lists of publications, meetings, granted permissions on lows and regulations concerning atomic energy, commendation, plans and outcomes in service and technical developments and so on. (author)

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2010. Operation, utilization and technical development of JRR-3, JRR-4, NSRR and Tandem Accelerator

International Nuclear Information System (INIS)

Ishii, Tetsuro; Nakamura, Kiyoshi; Kawamata, Satoshi; Yamada, Yusuke; Kawashima, Kazuhiro; Asozu, Takuhiro; Nakamura, Takemi; Arai, Masaji; Yoshinari, Shuji; Sataka, Masao

2012-03-01

The Department of Research Reactors and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3(Japan Research Reactor No.3), JRR-4(Japan Research Reactor No.4), NSRR(Nuclear Safety Research Reactor) and Tandem Accelerator. This annual report describes a summary of activities of services and technical developments carried out in the period between April 1, 2010 and March 31, 2011. The activities were categorized into five service/development fields: (1) Operation and maintenance of research reactors and tandem accelerator, (2) Utilization of research reactors and tandem accelerator, (3) Upgrading of utilization techniques of research reactors and tandem accelerator, (4) Safety administration for research reactors and tandem accelerator, (5) International cooperation. Also contained are lists of publications, meetings, granted permissions on lows and regulations concerning atomic energy, commendation, outcomes in service and technical developments and so on. (author)

The injector of the Utrecht EN tandem

International Nuclear Information System (INIS)

Borg, K. van der; Haas, A.P. de; Hoogenboom, A.M.; Strasters, B.A.; Vermeer, A.; Zwol, N.A. van

1984-01-01

An injector has been built to obtain improved beam transmission through the EN tandem. The injector has been provided with a 90 0 analysing magnet, m/Δm=300, and 130 kV preacceleration. Beam optics calculations have been made for the injector and tandem. The injector has been equipped with a fiber optics control and data acquisition system. (orig.)

Recent improvements of the tandem facility at LNS

International Nuclear Information System (INIS)

Ciavola, G.; Calabretta, L.; Cuttone, G.; Gammino, S.; Raia, G.; Rifuggiato, D.; Rovelli, A.; Scuderi, V.

1993-01-01

The Laboratorio Nazionale del Sud (LNS) of Catania is equipped with an upgraded 15 MV SMP tandem that is going to be coupled to a k=800 superconducting cyclotron. The status of the facility and the performances of the upgraded tandem are presented. (orig.)

Performance analysis of tandem queues with small buffers

NARCIS (Netherlands)

Vuuren, van M.; Adan, I.J.B.F.; Papadopoulos, C.T.

2005-01-01

In this paper we present an approximation for the performance analysis of single-server tandem queues with small buffers and generally distributed service times. The approximation is based on decomposition of the tandem queue in subsystems, the parameters of which are determined by an iterative

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2011. Operation, utilization and technical development of JRR-3, JRR-4, NSRR and tandem accelerator

International Nuclear Information System (INIS)

Ishii, Tetsuro; Nakamura, Kiyoshi; Kawamata, Satoshi; Ishikuro, Yasuhiro; Kawashima, Kazuhito; Kabumoto, Hiroshi; Nakamura, Takemi; Tamura, Itaru; Kawasaki, Sayuri; Sataka, Masao

2013-03-01

The Department of Research Reactors and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3(Japan Research Reactor No.3), JRR-4(Japan Research Reactor No.4), NSRR(Nuclear Safety Research Reactor) and Tandem Accelerator. This annual report describes a summary of activities of services and technical developments carried out in the period between April 1, 2011 and March 31, 2012. The activities were categorized into six service/development fields: (1) Recovery from the Great East Japan Earthquake, (2) Operation and maintenance of research reactors and tandem accelerator, (3) Utilization of research reactors and tandem accelerator, (4) Upgrading of utilization techniques of research reactors and tandem accelerator, (5) Safety administration for research reactors and tandem accelerator, (6) International cooperation. Also contained are lists of publications, meetings, granted permissions on lows and regulations concerning atomic energy, number of staff members dispatched to Fukushima for the technical assistance, commendation, outcomes in service and technical developments and so on. (author)

Targeted tandem duplication of a large chromosomal segment in Aspergillus oryzae.

Science.gov (United States)

Takahashi, Tadashi; Sato, Atsushi; Ogawa, Masahiro; Hanya, Yoshiki; Oguma, Tetsuya

2014-08-01

We describe here the first successful construction of a targeted tandem duplication of a large chromosomal segment in Aspergillus oryzae. The targeted tandem chromosomal duplication was achieved by using strains that had a 5'-deleted pyrG upstream of the region targeted for tandem chromosomal duplication and a 3'-deleted pyrG downstream of the target region. Consequently,strains bearing a 210-kb targeted tandem chromosomal duplication near the centromeric region of chromosome 8 and strains bearing a targeted tandem chromosomal duplication of a 700-kb region of chromosome 2 were successfully constructed. The strains bearing the tandem chromosomal duplication were efficiently obtained from the regenerated protoplast of the parental strains. However, the generation of the chromosomal duplication did not depend on the introduction of double-stranded breaks(DSBs) by I-SceI. The chromosomal duplications of these strains were stably maintained after five generations of culture under nonselective conditions. The strains bearing the tandem chromosomal duplication in the 700-kb region of chromosome 2 showed highly increased protease activity in solid-state culture, indicating that the duplication of large chromosomal segments could be a useful new breeding technology and gene analysis method.

Pathology of dogs in Campo Grande, MS, Brazil naturally co-infected with Leishmania infantum and Ehrlichia canis

Directory of Open Access Journals (Sweden)

Gisele Braziliano Andrade

2014-12-01

Full Text Available Different parasites that commonly occur concomitantly can influence one another, sometimes with unpredictable effects. We evaluated pathological aspects of dogs naturally co-infected with Leishmania infantum and Ehrlichia canis. The health status of the dogs was investigated based on histopathological, hematological and biochemical analyses of 21 animals infected solely with L. infantum and 22 dogs co- infected with L. infantum and E. canis. The skin of both groups showed chronic, predominantly lymphohistioplasmacytic inflammatory reaction. The plasmacytosis in the lymphoid tissues was likely related with the hypergammaglobulinemia detected in all the dogs. The disorganization of extracellular matrix found in the reticular dermis of the inguinal region and ear, characterized by the substitution of thick collagen fibers for thin fibers, was attributed to the degree of inflammatory reaction, irrespective of the presence of parasites. In addition, the histopathological analysis revealed that twice as many dogs in the co-infected group presented Leishmania amastigotes in the ear skin than those infected solely with Leishmania, increasing the possibility of becoming infected through sand fly vectors. Our findings highlight the fact that the health of dogs infected concomitantly with L. infantum and E. canis is severely compromised due to their high levels of total plasma protein, globulins, alkaline phosphatase and creatine kinase, and severe anemia.

Disease: H01142 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available H01142 Ehrlichia ewingii infection Human ehrlichiosis is a recently recognized tic...k-borne infection. Ehrlichia ewingii has been identified as a cause of human disease in addition to formerly... known pathogenic Ehrlichia species. Infectious disease ... Ehrlichia ewingii ... 16S rRNA [KO:K01977] ... Other dis... Manian FA, Liddell AM, Schmulewitz N, Storch GA ... TITLE ... Ehrlichia ewingii, a

Quality evaluation of tandem mass spectral libraries.

Science.gov (United States)

Oberacher, Herbert; Weinmann, Wolfgang; Dresen, Sebastian

2011-06-01

Tandem mass spectral libraries are gaining more and more importance for the identification of unknowns in different fields of research, including metabolomics, forensics, toxicology, and environmental analysis. Particularly, the recent invention of reliable, robust, and transferable libraries has increased the general acceptance of these tools. Herein, we report on results obtained from thorough evaluation of the match reliabilities of two tandem mass spectral libraries: the MSforID library established by the Oberacher group in Innsbruck and the Weinmann library established by the Weinmann group in Freiburg. Three different experiments were performed: (1) Spectra of the libraries were searched against their corresponding library after excluding either this single compound-specific spectrum or all compound-specific spectra prior to searching; (2) the libraries were searched against each other using either library as reference set or sample set; (3) spectra acquired on different mass spectrometric instruments were matched to both libraries. Almost 13,000 tandem mass spectra were included in this study. The MSforID search algorithm was used for spectral matching. Statistical evaluation of the library search results revealed that principally both libraries enable the sensitive and specific identification of compounds. Due to higher mass accuracy of the QqTOF compared with the QTrap instrument, matches to the MSforID library were more reliable when comparing spectra with both libraries. Furthermore, only the MSforID library was shown to be efficiently transferable to different kinds of tandem mass spectrometers, including "tandem-in-time" instruments; this is due to the coverage of a large range of different collision energy settings-including the very low range-which is an outstanding characteristics of the MSforID library.

High-sensitivity mass spectrometry with a tandem accelerator

International Nuclear Information System (INIS)

Henning, W.

1984-01-01

The characteristic features of accelerator mass spectrometry are discussed. A short overview is given of the current status of mass spectrometry with high-energy (MeV/nucleon) heavy-ion accelerators. Emphasis is placed on studies with tandem accelerators and on future mass spectrometry of heavier isotopes with the new generation of higher-voltage tandems

Single-task and dual-task tandem gait test performance after concussion.

Science.gov (United States)

Howell, David R; Osternig, Louis R; Chou, Li-Shan

2017-07-01

To compare single-task and dual-task tandem gait test performance between athletes after concussion with controls on observer-timed, spatio-temporal, and center-of-mass (COM) balance control measurements. Ten participants (19.0±5.5years) were prospectively identified and completed a tandem gait test protocol within 72h of concussion and again 1 week, 2 weeks, 1 month, and 2 months post-injury. Seven uninjured controls (20.0±4.5years) completed the same protocol in similar time increments. Tandem gait test trials were performed with (dual-task) and without (single-task) concurrently performing a cognitive test as whole-body motion analysis was performed. Outcome variables included test completion time, average tandem gait velocity, cadence, and whole-body COM frontal plane displacement. Concussion participants took significantly longer to complete the dual-task tandem gait test than controls throughout the first 2 weeks post-injury (mean time=16.4 [95% CI: 13.4-19.4] vs. 10.1 [95% CI: 6.4-13.7] seconds; p=0.03). Single-task tandem gait times were significantly lower 72h post-injury (p=0.04). Dual-task cadence was significantly lower for concussion participants than controls (89.5 [95% CI: 68.6-110.4] vs. 127.0 [95% CI: 97.4-156.6] steps/minute; p=0.04). Moderately-high to high correlations between tandem gait test time and whole-body COM medial-lateral displacement were detected at each time point during dual-task gait (r s =0.70-0.93; p=0.03-0.001). Adding a cognitive task during the tandem gait test resulted in longer detectable deficits post-concussion compared to the traditional single-task tandem gait test. As a clinical tool to assess dynamic motor function, tandem gait may assist with return to sport decisions after concussion. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Study of Tandem Accelerator Technology and Its Prospects

International Nuclear Information System (INIS)

Sigit-Hariyanto; Sudjatmoko; Djoko-S-Pudjorahardjo; Suryadi; Widdi-Usada; Suprapto; Djasiman; Tono-Wibowo; Agus-Purwadi

2000-01-01

Tandem accelerator is an ion acceleration tool in which negative ions injected in the accelerator tube and stripped to become positive ions, then accelerated by electrostatic high voltage such that its energy is multiplied. In this paper, we describe the prospect of accelerator application briefly in agriculture and biotechnology, industry, health and medicine, environment fields. Technical study on tandem accelerator included SNICS and alphatross ion sources, acceleration system and stripper system. The study result for many kinds of negative ions and its current which should be injected in the accelerator tube and the output of tandem accelerator H + , and the distribution of C + , Ni + , Au + , Br + ion on varying charge state is shown. (author)

Negotiating Multiple Identities through eTandem Learning Experiences

Science.gov (United States)

Yang, Se Jeong; Yi, Youngjoo

2017-01-01

Much of eTandem research has investigated either linguistic or cross-cultural aspects of second language (L2) learning, but relatively little is known about issues of identity construction in an eTandem context. Situating the study within theories and research of language learner identity, we examined ways in which two adult L2 learners (a Korean…

Hybrid tandem photovoltaic devices with a transparent conductive interconnecting recombination layer

International Nuclear Information System (INIS)

Kim, Taehee; Choi, Jin Young; Jeon, Jun Hong; Kim, Youn-Su; Kim, Bong-Soo; Lee, Doh-Kwon; Kim, Honggon; Han, Seunghee; Kim, Kyungkon

2012-01-01

Highlights: ► This work enhanced power conversion efficiency of the hybrid tandem solar cell from 1.0% to 2.6%. ► The interfacial series resistance of the tandem solar cell was eliminated by inserting ITO layer. ► This work shows the feasibility of the highly efficient hybrid tandem solar cells. -- Abstract: We demonstrate hybrid tandem photovoltaic devices with a transparent conductive interconnecting recombination layer. The series-connected hybrid tandem photovoltaic devices were developed by combining hydrogenated amorphous silicon (a-Si:H) and polymer-based organic photovoltaics (OPVs). In order to enhance the interfacial connection between the subcells, we employed highly transparent and conductive indium tin oxide (ITO) thin layer. By using the ITO interconnecting layer, the power conversion efficiency of the hybrid tandem solar cell was enhanced from 1.0% (V OC = 1.041 V, J SC = 2.97 mA/cm 2 , FF = 32.3%) to 2.6% (V OC = 1.336 V, J SC = 4.65 mA/cm 2 , FF = 41.98%) due to the eliminated interfacial series resistance.

Tandem Van de Graaff facility

Data.gov (United States)

Federal Laboratory Consortium — Completed in 1970, the Tandem Van de Graaff facility was for many years the world's largest electrostatic accelerator facility. It can provide researchers with beams...

AVALIAÇÃO DE INICIADORES E PROTOCOLO PARA O DIAGNÓSTICO DA PANCITOPENIA TROPICAL CANINA POR PCR

Directory of Open Access Journals (Sweden)

Daniel C. L. Linhares

2006-10-01

Full Text Available Este trabalho foi desenvolvido com o objetivo de padronizar um protocolo para a reação em cadeia da polimerase (PCR e selecionar oligonucleotídeos iniciadores para a detecção específica de Ehrlichia canis, em uma única etapa de reação. Inicialmente foram obtidas seqüências depositadas no Genbank, referentes ao gene que codifica o 16S rRNA das espécies E. canis (número de acesso = AF162860, E. ewingii (U96436, E. platys (AF1567844, E. chaffeensis, (U86665, E. phagocytophila genogrupo (U02521, E. bovis (AF294789 e E. risticii (M21290, as quais foram submetidas ao alinhamento genético para a construção dos iniciadores. Do alinhamento foi selecionado, a partir de uma região semiconservada, um iniciador específico para E. canis, designado EBR1 (5’-cctctggctataggaaattg- 3’ e, de uma região conservada, um iniciador genérico EBR5 (5’-ggagtgcttaacgcgttag- 3’. Paralelamente foram obtidas amostras de sangue de dez cães que apresentavam infecção aguda por E. canis, confirmado pela presença de mórulas intracitoplasmáticas, características da riquétsia, em células mononucleares sangüíneas. O DNA genômico extraído dessas amostras foi utilizado para a avaliação da reação de PCR, empregando-se um protocolo adaptado de outros autores e o par de oligos EBR1/EBR5, selecionado neste trabalho. A reação de PCR apresentou resultados positivos para os 10 isolados de E. canis, amplificando o fragmento esperado de 765 pares de bases do gene 16S rRNA. Resultados negativos verificados nas reações de PCR para amostras de DNA genômico de Babesia canis, Hepatozoon canis, Haemobartonella sp., Trypanosoma evansi e do hospedeiro (Canis familiaris livre de infecção indicaram a segurança do método quanto à especificidade para a discriminação de E. canis. PALAVRAS-CHAVE: Cães, Ehrlichia canis, erliquiose canina, hemoparasitose, reação em cadeia da polimerase

The tandem betatron accelerator

International Nuclear Information System (INIS)

Keinigs, R.

1991-01-01

This paper reports that the tandem betatron is a compact, high-current induction accelerator that has the capability to accelerate electrons to an energy of order one gigavolt. Based upon the operating principle of a conventional betatron, the tandem betatron employs two synchronized induction cores operating 180 degrees out of phase. Embedded within the cores are the vacuum chambers, and these are connected by linear transport sections to allow for moving the beam back and forth between the two betatrons. The 180 degree phase shift between the core fluxes permits the circumvention of the flux swing constraint that limits the maximum energy gain of a conventional betatron. By transporting the beam between the synchronized cores, an electron can access more than one acceleration cycle, and thereby continue to gain energy. This added degree of freedom also permits a significant decrease in the size of the magnet system. Biasing coils provide independent control of the confining magnetic field. Provided that efficient beam switching can be performed, it appears feasible that a one gigavolt electron beam can be generated and confined. At this energy, a high current electron beam circulating in a one meter radius orbit could provide a very intense source of short wavelength (λ < 10 nm) synchrotron radiation. This has direct application to the emerging field of x-ray lithography. At more modest energies (10 MeV-30 MEV) a compact tandem betatron could be employed in the fields of medical radiation therapy, industrial radiography, and materials processing

The design and numerical analysis of tandem thermophotovoltaic cells

International Nuclear Information System (INIS)

Yang Hao-Yu; Liu Ren-Jun; Wang Lian-Kai; Lü You; Li Tian-Tian; Li Guo-Xing; Zhang Yuan-Tao; Zhang Bao-Lin

2013-01-01

In this paper, numerical analysis of GaSb =(E g = 0.72 eV)/Ga 0.84 In 0.16 As 0.14 Sb 0.86 (E g = 0.53 eV) tandem thermophotovoltaic (TPV) cells is carried out by using Silvaco/Atlas software. In the tandem cells, a GaSb p-n homojunction is used for the top cell and a GaInAsSb p-n homojunction for the bottom cell. A heavily doped GaSb tunnel junction connects the two sub-cells together. The simulations are carried out at a radiator temperature of 2000 K and a cell temperature of 300 K. The radiation photons are injected from the top of the tandem cells. Key properties of the single- and dual-junction TPV cells, including I–V characteristic, maximum output power (P max ), open-circuit voltage (V oc ), short-circuit current (I sc ), etc. are presented. The effects of the sub-cell thickness and carrier concentration on the key properties of tandem cells are investigated. A comparison of the dual-TPV cells with GaSb and GaInAsSb single junction cells shows that the P max of tandem cells is almost twice as great as that of the single-junction cells. (interdisciplinary physics and related areas of science and technology)

DNA Damage by Ionizing Radiation: Tandem Double Lesions by Charged Particles

Science.gov (United States)

Huo, Winifred M.; Chaban, Galina M.; Wang, Dunyou; Dateo, Christopher E.

2005-01-01

Oxidative damages by ionizing radiation are the source of radiation-induced carcinogenesis, damage to the central nervous system, lowering of the immune response, as well as other radiation-induced damages to human health. Monte Carlo track simulations and kinetic modeling of radiation damages to the DNA employ available molecular and cellular data to simulate the biological effect of high and low LET radiation io the DNA. While the simulations predict single and double strand breaks and base damages, so far all complex lesions are the result of stochastic coincidence from independent processes. Tandem double lesions have not yet been taken into account. Unlike the standard double lesions that are produced by two separate attacks by charged particles or radicals, tandem double lesions are produced by one single attack. The standard double lesions dominate at the high dosage regime. On the other hand, tandem double lesions do not depend on stochastic coincidences and become important at the low dosage regime of particular interest to NASA. Tandem double lesions by hydroxyl radical attack of guanine in isolated DNA have been reported at a dosage of radiation as low as 10 Gy. The formation of two tandem base lesions was found to be linear with the applied doses, a characteristic of tandem lesions. However, tandem double lesions from attack by a charged particle have not been reported.

Neorickettsia sennetsu as a Neglected Cause of Fever in South-East Asia.

Directory of Open Access Journals (Sweden)

Sabine Dittrich

Full Text Available Neorickettsia sennetsu infection is rarely recognized, with less than 100 globally reported patients over the last 50 years. The disease is thought to be contracted by eating raw fish, a staple of many South-East Asian cuisines. In 2009, the first patient with sennetsu was identified in the Lao PDR (Laos, raising the question as to how common this organism and related species are in patients presenting with fever. We investigated the frequency of N. sennetsu infection at hospitals in diverse areas of Laos. Consenting febrile hospital inpatients from central (Vientiane: n = 1,013, northern (Luang Namtha: n = 453 and southern (Salavan: n = 171 Laos were screened by PCR for N. sennetsu, if no previous positive direct diagnostic test was available. A PCR-restriction fragment length polymorphism assay was developed to differentiate between N. sennetsu, Ehrlichia chaffeensis and Anaplasma phagocytophilum. To allow more detailed studies of N. sennetsu, culture was successfully established using a reference strain (ATCC VR-367, identifying a canine-macrophage cell line (DH82 to be most suitable to visually identify infection. After screening, N. sennetsu was identified and sequence confirmed in four (4/1,637; 0.2% Lao patients. Despite the previously identified high seroprevalence of N. sennetsu antibodies in the Lao population (~17%, acute N. sennetsu infection with sufficient clinical signs to prompt hospitalization appears to be rare. The reservoir, zoonotic cycle and pathogenicity of N. sennetsu remain unclear and require further investigations.

Neorickettsia sennetsu as a Neglected Cause of Fever in South-East Asia.

Science.gov (United States)

Dittrich, Sabine; Phuklia, Weerawat; Turner, Gareth D H; Rattanavong, Sayaphet; Chansamouth, Vilada; Dumler, Stephen J; Ferguson, David J P; Paris, Daniel H; Newton, Paul N

2015-01-01

Neorickettsia sennetsu infection is rarely recognized, with less than 100 globally reported patients over the last 50 years. The disease is thought to be contracted by eating raw fish, a staple of many South-East Asian cuisines. In 2009, the first patient with sennetsu was identified in the Lao PDR (Laos), raising the question as to how common this organism and related species are in patients presenting with fever. We investigated the frequency of N. sennetsu infection at hospitals in diverse areas of Laos. Consenting febrile hospital inpatients from central (Vientiane: n = 1,013), northern (Luang Namtha: n = 453) and southern (Salavan: n = 171) Laos were screened by PCR for N. sennetsu, if no previous positive direct diagnostic test was available. A PCR-restriction fragment length polymorphism assay was developed to differentiate between N. sennetsu, Ehrlichia chaffeensis and Anaplasma phagocytophilum. To allow more detailed studies of N. sennetsu, culture was successfully established using a reference strain (ATCC VR-367), identifying a canine-macrophage cell line (DH82) to be most suitable to visually identify infection. After screening, N. sennetsu was identified and sequence confirmed in four (4/1,637; 0.2%) Lao patients. Despite the previously identified high seroprevalence of N. sennetsu antibodies in the Lao population (~17%), acute N. sennetsu infection with sufficient clinical signs to prompt hospitalization appears to be rare. The reservoir, zoonotic cycle and pathogenicity of N. sennetsu remain unclear and require further investigations.

Optical klystron FELs based on tandem electrostatic accelerators

International Nuclear Information System (INIS)

Gover, A.; Friedman, A.

1989-01-01

The operation of tandem electrostatic accelerator FELs in an optical klystron configuration makes it possible to take advantage of the high quality (low emittance and low energy spread) of the electron beam in electrostatic accelerators. With evolving microwiggler technology, state-of-the-art moderate energy (6-14-MeV) tandem electrostatic accelerators may be used for the development of highly coherent tunable radiation sources in the entire IR region. The authors present the general design considerations and the predicted operating characteristics of such devices and refer in specifics to a design of a 10-1000-μm FEL based on the parameters of a 5-6-MeV high current tandem accelerator. The operating wavelength of FELs is determined by the Doppler shift formula

Superconducting linacs used with tandems

International Nuclear Information System (INIS)

Ben-Zvi, I.

1984-01-01

The main features of superconducting linacs used as post-accelerators of tandems are reviewed. Various aspects of resonators, cryogenics and electronics are discussed, and recent advances in the field are presented. (orig.)

Classroom tandem – Outlining a model for language learning and ınstruction

Directory of Open Access Journals (Sweden)

Katri Karjalaınen

2013-11-01

Full Text Available The aim of this paper is to outline classroom tandem by comparing it with informal tandem learning contexts and other language instruction methods. Classroom tandem is used for second language instruction in mixed language groups in the subjects of Finnish and Swedish as L2. Tandem learning entails that two persons with different mother tongues learn each other’s native languages in reciprocal cooperation. The students function, in turns, as a second language learner and as a model in the native language. We aim to give an overview description of the interaction in classroom tandem practice. The empirical data consists of longitudinal video recordings of meetings of one tandem dyad within a co-located Swedishmedium and Finnish-medium school. Focus in the analysis is on the language aspects the informants orient to and topicalize in their interaction. The language aspects vary depending on what classroom activities they are engaged in, text-based or oral activities.

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2012. Operation, utilization and technical development of JRR-3, JRR-4, NSRR, Tandem Accelerator and RI Production Facility

International Nuclear Information System (INIS)

Murayama, Yoji; Ishii, Tetsuro; Nakamura, Kiyoshi; Uno, Yuki; Ishikuro, Yasuhiro; Kawashima, Kazuhito; Ishizaki, Nobuhiro; Matsumura, Taichi; Nagahori, Kazuhisa; Odauchi, Shouji; Maruo, Takeshi

2014-03-01

The Department of Research Reactor and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3(Japan Research Reactor No.3), JRR-4(Japan Research Reactor No.4), NSRR(Nuclear Safety Research Reactor), Tandem Accelerator and RI Production Facility. This annual report describes a summary of activities of services and technical developments carried out in the period between April 1, 2012 and March 31, 2013. The activities were categorized into five service/development fields: (1) Operation and maintenance of research reactors and tandem accelerator, (2) Utilization of research reactors and tandem accelerator, (3) Upgrading of utilization techniques of research reactors and tandem accelerator, (4) Safety administration for department of research reactor and tandem accelerator, (5) International cooperation. Also contained are lists of publications, meetings, granted permissions on laws and regulations concerning atomic energy, number of staff members dispatched to Fukushima for the technical assistance, outcomes in service and technical developments and so on. (author)

Simulation of forward dark current voltage characteristics of tandem solar cells

International Nuclear Information System (INIS)

Rubinelli, F.A.

2012-01-01

The transport mechanisms tailoring the shape of dark current–voltage characteristics of amorphous and microcrystalline silicon based tandem solar cell structures are explored with numerical simulations. Our input parameters were calibrated by fitting experimental current voltage curves of single and double junction structures measured under dark and illuminated conditions. At low and intermediate forward voltages the dark current–voltage characteristics show one or two regions with a current–voltage exponential dependence. The diode factor is unique in tandem cells with the same material in both intrinsic layers and two dissimilar diode factors are observed in tandem cells with different materials on the top and bottom intrinsic layers. In the exponential regions the current is controlled by recombination through gap states and by free carrier diffusion. At high forward voltages the current grows more slowly with the applied voltage. The current is influenced by the onset of electron space charge limited current (SCLC) in tandem cells where both intrinsic layers are of amorphous silicon and by series resistance of the bottom cell in tandem cells where both intrinsic layers are of microcrystalline silicon. In the micromorph cell the onset of SCLC becomes visible on the amorphous top sub-cell. The dark current also depends on the thermal generation of electron–hole (e–h) pairs present at the tunneling recombination junction. The highest dependence is observed in the tandem structure where both intrinsic layers are of microcrystalline silicon. The prediction of meaningless dark currents at low forward and reverse voltages by our code is discussed and one solution is given. - Highlights: ► Transport mechanisms shaping the dark current-voltage curves of tandem devices. ► The devices are amorphous and microcrystalline based tandem solar cells. ► Two regions with a current-voltage exponential dependence are observed. ► The tandem J-V diode factor is the

Heavy-atom neutral beams for tandem-mirror end plugs

International Nuclear Information System (INIS)

Post, D.E.; Grisham, L.R.; Santarius, J.F.; Emmert, G.A.

1981-05-01

The advantages of neutral beams with Z greater than or equal to 3 formed from negative ions, accelerated to 0.5 to 1.0 MeV/amu, and neutralized with high efficiency, are investigated for use in tandem mirror reactor end plugs. These beams can produce Q's of 20 to 30, and thus can replace the currently proposed 200 to 500 keV neutral proton beams presently planned for tandem mirror reactors. Thus, these Z greater than or equal to 3 neutral beams increase the potential attractiveness of tandem mirror reactors by offering a substitute for difficult high energy neutral hydrogen end plug beams

Operation of the tandem-linac accelerator

International Nuclear Information System (INIS)

Anon.

1985-01-01

The tandem-linac accelerator system is operated as a source of energetic heavy-ion projectiles for research in several areas of nuclear physics and occasionally in other areas of science. The accelerator system consists of a 9-MV tandem electrostatic accelerator and a superconducting-linac energy booster that can provide an additional 20 MV of acceleration. A figure shows the layout of this system, which will be operated in its present form until September 1985, when it will be incorporated into the larger ATLAS system. In both the present and future forms the accelerator is designed to provide the exceptional beam quality and overall versatility required for precision nuclear-structure research

MINIMARS tandem mirror reactor study

International Nuclear Information System (INIS)

Perkins, L.J.; Logan, B.G.; Doggett, J.N.

1986-01-01

During 1985-1986, Lawrence Livermore National Lab., in partnership with the Fusion Engineering Design Center of Oak Ridge National Lab., the Univ. of Wisconsin, TRW, Grumman Aerospace Corporation, General Dynamics/Convair, Argonne National Lab., and the Canadian Fusion Fuels Technology Project, has conducted the conceptual design of MINIMARS, a small commercial tandem mirror reactor with novel octopole end plugs. With a net electric output of 600 MW(e), MINIMARS is expressly designed for short (∼4- to 5-yr) construction time, factory-built modules, and a passively safe blanket and thermal cycle. In this way, we intend to achieve a small reactor based on the tandem mirror principle that will minimize utility financial risk, thereby providing an attractive alternative to the more conventional large fusion plant designs encountered to date

Semi-transparent perovskite solar cells for tandems with silicon and CIGS

KAUST Repository

Bailie, Colin D.

2015-01-01

© 2015 The Royal Society of Chemistry. A promising approach for upgrading the performance of an established low-bandgap solar technology without adding much cost is to deposit a high bandgap polycrystalline semiconductor on top to make a tandem solar cell. We use a transparent silver nanowire electrode on perovskite solar cells to achieve a semi-transparent device. We place the semi-transparent cell in a mechanically-stacked tandem configuration onto copper indium gallium diselenide (CIGS) and low-quality multicrystalline silicon (Si) to achieve solid-state polycrystalline tandem solar cells with a net improvement in efficiency over the bottom cell alone. This work paves the way for integrating perovskites into a low-cost and high-efficiency (>25%) tandem cell.

Solution-Processed Nanocrystal Quantum Dot Tandem Solar Cells

KAUST Repository

Choi, Joshua J.; Wenger, Whitney N.; Hoffman, Rachel S.; Lim, Yee-Fun; Luria, Justin; Jasieniak, Jacek; Marohn, John A.; Hanrath, Tobias

2011-01-01

Solution-processed tandem solar cells created from nanocrystal quantum dots with size-tuned energy levels are demonstrated. Prototype devices featuring interconnected quantum dot layers of cascaded energy gaps exhibit IR sensitivity and an open circuit voltage, V oc, approaching 1 V. The tandem solar cell performance depends critically on the optical and electrical properties of the interlayer. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Solution-Processed Nanocrystal Quantum Dot Tandem Solar Cells

KAUST Repository

Choi, Joshua J.

2011-06-03

Solution-processed tandem solar cells created from nanocrystal quantum dots with size-tuned energy levels are demonstrated. Prototype devices featuring interconnected quantum dot layers of cascaded energy gaps exhibit IR sensitivity and an open circuit voltage, V oc, approaching 1 V. The tandem solar cell performance depends critically on the optical and electrical properties of the interlayer. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Economic viability of thin-film tandem solar modules in the United States

Science.gov (United States)

Sofia, Sarah E.; Mailoa, Jonathan P.; Weiss, Dirk N.; Stanbery, Billy J.; Buonassisi, Tonio; Peters, I. Marius

2018-05-01

Tandem solar cells are more efficient but more expensive per unit area than established single-junction (SJ) solar cells. To understand when specific tandem architectures should be utilized, we evaluate the cost-effectiveness of different II-VI-based thin-film tandem solar cells and compare them to the SJ subcells. Levelized cost of electricity (LCOE) and energy yield are calculated for four technologies: industrial cadmium telluride and copper indium gallium selenide, and their hypothetical two-terminal (series-connected subcells) and four-terminal (electrically independent subcells) tandems, assuming record SJ quality subcells. Different climatic conditions and scales (residential and utility scale) are considered. We show that, for US residential systems with current balance-of-system costs, the four-terminal tandem has the lowest LCOE because of its superior energy yield, even though it has the highest US per watt (US W-1) module cost. For utility-scale systems, the lowest LCOE architecture is the cadmium telluride single junction, the lowest US W-1 module. The two-terminal tandem requires decreased subcell absorber costs to reach competitiveness over the four-terminal one.

Establishment of a tandem ionization chamber system in standard mammography beams

International Nuclear Information System (INIS)

Silva, Jonas O. da; Caldas, L.V.E.

2011-01-01

A double-faced tandem ionization chamber system was developed at the Calibration Laboratory of IPEN. It has different collecting electrode materials: aluminium and graphite. The response repeatability and reproducibility and the energy dependence test of this tandem ionization chamber were evaluated. The chamber response stability is within the ±3% limit recommended in international standards. The energy dependence test of the ionization chamber system using the tandem curve obtained, presented agreement with literature results. (author)

Optochemokine Tandem for Light-Control of Intracellular Ca2.

Directory of Open Access Journals (Sweden)

Katrin Feldbauer

Full Text Available An optochemokine tandem was developed to control the release of calcium from endosomes into the cytosol by light and to analyze the internalization kinetics of G-protein coupled receptors (GPCRs by electrophysiology. A previously constructed rhodopsin tandem was re-engineered to combine the light-gated Ca2+-permeable cation channel Channelrhodopsin-2(L132C, CatCh, with the chemokine receptor CXCR4 in a functional tandem protein tCXCR4/CatCh. The GPCR was used as a shuttle protein to displace CatCh from the plasma membrane into intracellular areas. As shown by patch-clamp measurements and confocal laser scanning microscopy, heterologously expressed tCXCR4/CatCh was internalized via the endocytic SDF1/CXCR4 signaling pathway. The kinetics of internalization could be followed electrophysiologically via the amplitude of the CatCh signal. The light-induced release of Ca2+ by tandem endosomes into the cytosol via CatCh was visualized using the Ca2+-sensitive dyes rhod2 and rhod2-AM showing an increase of intracellular Ca2+ in response to light.

II-IV-V Based Thin Film Tandem Photovoltaic Cell

Energy Technology Data Exchange (ETDEWEB)

Newman, Nathan [Arizona State Univ., Mesa, AZ (United States); van Schilfgaarde, Mark [Arizona State Univ., Mesa, AZ (United States)

2012-10-04

[Through a combination of theory and experiment that, absent unknown mitigating factors, a tandem cell whose (wide-gap. 1.8 eV) top layer is made of ZnSnP2 and whose (narrow gap, 1.1 eV) bottom layer consisting of ZnGeAs2 are near-ideal materials for a tandem cell. Not only are there gaps optimally adjusted to the solar spectrum, but the two compounds are lattice-matched, and their energy band structure and optical absorption are also near-ideal (they closely resemble that of GaAs). Our first major challenge is to establish that high-quality II-IV-V thin films can be synthesized. We have begun growing and characterizing films of ZnGeAs2 and ZnSnP2, initially grown on Ge substrates (the lattice constant of Ge matches these compounds) by pulsed laser ablation and sputtering. In tandem are theoretical calculations to guide the experiments. The goal is to develop methods that can be used to produce a pair of lattice-matched thin films that will be useful in tandem cells.

Solution-processed parallel tandem polymer solar cells using silver nanowires as intermediate electrode.

Science.gov (United States)

Guo, Fei; Kubis, Peter; Li, Ning; Przybilla, Thomas; Matt, Gebhard; Stubhan, Tobias; Ameri, Tayebeh; Butz, Benjamin; Spiecker, Erdmann; Forberich, Karen; Brabec, Christoph J

2014-12-23

Tandem architecture is the most relevant concept to overcome the efficiency limit of single-junction photovoltaic solar cells. Series-connected tandem polymer solar cells (PSCs) have advanced rapidly during the past decade. In contrast, the development of parallel-connected tandem cells is lagging far behind due to the big challenge in establishing an efficient interlayer with high transparency and high in-plane conductivity. Here, we report all-solution fabrication of parallel tandem PSCs using silver nanowires as intermediate charge collecting electrode. Through a rational interface design, a robust interlayer is established, enabling the efficient extraction and transport of electrons from subcells. The resulting parallel tandem cells exhibit high fill factors of ∼60% and enhanced current densities which are identical to the sum of the current densities of the subcells. These results suggest that solution-processed parallel tandem configuration provides an alternative avenue toward high performance photovoltaic devices.

Efficient organic tandem solar cells based on small molecules

Energy Technology Data Exchange (ETDEWEB)

Riede, Moritz; Widmer, Johannes; Timmreck, Ronny; Wynands, David; Leo, Karl [Institut fuer Angewandte Photophysik, Technische Universitaet Dresden, George-Baehr-Str. 1, 01069 Dresden (Germany); Uhrich, Christian; Schwartz, Gregor; Gnehr, Wolf-Michael; Hildebrandt, Dirk; Weiss, Andre; Pfeiffer, Martin [Heliatek GmbH, Treidlerstr. 3, 01139 Dresden (Germany); Hwang, Jaehyung; Sundarraj, Sudhakar; Erk, Peter [BASF SE, GVC/E-J542, 67056 Ludwigshafen (Germany)

2011-08-23

In this paper, two vacuum processed single heterojunction organic solar cells with complementary absorption are described and the construction and optimization of tandem solar cells based on the combination of these heterojunctions demonstrated. The red-absorbing heterojunction consists of C{sub 60} and a fluorinated zinc phthalocyanine derivative (F4-ZnPc) that leads to a 0.1-0.15 V higher open circuit voltage V{sub oc} than the commonly used ZnPc. The second heterojunction incorporates C{sub 60} and a dicyanovinyl-capped sexithiophene derivative (DCV6T) that mainly absorbs in the green. The combination of both heterojunctions into one tandem solar cell leads to an absorption over the whole visible range of the sun spectrum. Thickness variations of the transparent p-doped optical spacer between both subcells in the tandem solar cell is shown to lead to a significant change in short circuit current density j{sub sc} due to optical interference effects, whereas V{sub oc} and fill factor are hardly affected. The maximum efficiency {eta} of about 5.6% is found for a spacer thickness of 150-165 nm. Based on the optimized 165nm thick spacer, effects of intensity and angle of illumination, and temperature on a tandem device are investigated. Variations in illumination intensity lead to a linear change in j{sub sc} over three orders of magnitude and a nearly constant {eta} in the range of 30 to 310 mW cm{sup -2}. Despite the stacked heterojunctions, the performance of the tandem device is robust against different illumination angles: j{sub sc} and {eta} closely follow a cosine behavior between 0 and 70 . Investigations of the temperature behavior of the tandem device show an increase in {eta} of 0.016 percentage points per Kelvin between -20 C and 25 C followed by a plateau up to 50 C. Finally, further optimization of the tandem stack results in a certified {eta} of (6.07 {+-} 0.24)% on (1.9893 {+-} 0.0060)cm{sup 2} (Fraunhofer ISE), i.e., areas large enough to be of

Sequence-specific DNA alkylation by tandem Py-Im polyamide conjugates.

Science.gov (United States)

Taylor, Rhys Dylan; Kawamoto, Yusuke; Hashiya, Kaori; Bando, Toshikazu; Sugiyama, Hiroshi

2014-09-01

Tandem N-methylpyrrole-N-methylimidazole (Py-Im) polyamides with good sequence-specific DNA-alkylating activities have been designed and synthesized. Three alkylating tandem Py-Im polyamides with different linkers, which each contained the same moiety for the recognition of a 10 bp DNA sequence, were evaluated for their reactivity and selectivity by DNA alkylation, using high-resolution denaturing gel electrophoresis. All three conjugates displayed high reactivities for the target sequence. In particular, polyamide 1, which contained a β-alanine linker, displayed the most-selective sequence-specific alkylation towards the target 10 bp DNA sequence. The tandem Py-Im polyamide conjugates displayed greater sequence-specific DNA alkylation than conventional hairpin Py-Im polyamide conjugates (4 and 5). For further research, the design of tandem Py-Im polyamide conjugates could play an important role in targeting specific gene sequences. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DNA radio-induced tandem lesions: formation, introduction in oligonucleotides and repair

International Nuclear Information System (INIS)

Bourdat, Anne-Gaelle

2000-01-01

Cell killing induced by excited photosensitizers, ionizing radiation or radiomimetic drugs can not be only explained by the formation of single DNA lesions. Thus, multiply damaged sites, are likely to have harmful biological consequences. One example of tandem base damage induced by ".OH radical in X-irradiated aqueous solution of DNA oligomers is N-(2-deoxy-β-D-erythro-pentofuranosyl)-formyl-amine (dβF)/8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo). In order to investigate the biological significance of such a tandem lesion, both 8-oxodGuo and dβF were introduced in synthetic oligonucleotides at vicinal positions using the solid phase phosphoramidite method with the 'Pac phosphoramidite' chemistry. The purity of the synthetic DNA fragments and the integrity of modified nucleosides was confirmed using different complementary techniques: HPLC, PAGE, ESI MS, MALDI-TOF MS and capillary electrophoresis. Using the above synthetic substrates, investigations were carried out in order to determine the substrate specificity and the excision mechanism of three glycosylases involved in the base excision repair pathway: endonuclease III, Fpg and yOggl. Both tandem lesions were substrates for the BER enzymes. However, the tandem lesion are not completely excised by the repair enzymes. The rates of excision as inferred from the determination of the ratios of Vm/Km Michaelis kinetics constants were not found to be significantly affected by the presence of the tandem lesions. MALDI-TOF mass spectrometry was used in order to gain insights into mechanistic aspects of oligonucleotide cleavage by the BER enzymes. During in vitro DNA synthesis by Taq DNA polymerase, Klenow fragment exo- and DNA polymerase β, tandem base damage were found to block the progression of the enzymes. Finally, the level of tandem base damage in the DNA exposed to γ-ray using the liquid chromatography coupled to electro-spray ionization tandem mass spectrometry was determined. Both dβF-8-oxodGuo and 8

TMX-U [Tandem Mirror Experiment-Upgrade] tandem-mirror thermal-barrier experiments

International Nuclear Information System (INIS)

Simonen, T.C.; Allen, S.L.; Baldwin, D.E.

1986-01-01

Thermal-barrier experiments have been carried out in the Tandem Mirror Experiment-Upgrade (TMX-U). Measurements of nonambipolar and ambipolar radial transport show that these transport processes, as well as end losses, can be controlled at modest densities and durations. Central-cell heating methods using ion-cyclotron heating (ICH) and neutral-beam injection have been demonstrated. Potential mesurements with recently developed methods indicate that deep thermal barriers can be established

Tandem mirror reactor studies at Lawrence Livermore National Laboratory, FY 1980

Energy Technology Data Exchange (ETDEWEB)

Carlson, G.A.; Neef, W.S. Jr.

1981-03-20

The principles of tandem mirror operation with thermal barriers will be demonstrated in the upgrade of the Tandem Mirror Experiment (TMX-U) in 1981 and the tandem configuration of the Mirror Fusion Test Facility (MFTF-B) in 1984. Continued analysis and conceptual design over this period will evolve the optimal configuration and parameters for a power-producing reactor. In this article we describe the progress we have made in this reactor design study effort during 1980.

Tandem mirror reactor studies at Lawrence Livermore National Laboratory, FY 1980

International Nuclear Information System (INIS)

Carlson, G.A.; Neef, W.S. Jr.

1981-01-01

The principles of tandem mirror operation with thermal barriers will be demonstrated in the upgrade of the Tandem Mirror Experiment (TMX-U) in 1981 and the tandem configuration of the Mirror Fusion Test Facility (MFTF-B) in 1984. Continued analysis and conceptual design over this period will evolve the optimal configuration and parameters for a power-producing reactor. In this article we describe the progress we have made in this reactor design study effort during 1980

Soroprevalência e fatores de risco associados à soropositividade para Ehrlichia canis em cães do semiárido da Paraíba

Directory of Open Access Journals (Sweden)

Sérgio Santos de Azevedo

2011-02-01

Full Text Available Aiming to determine the seroprevalence of Ehrlichia canis infection, as well as to identify risk factors associated to the seropositivity, a serological survey was conducted in 109 dogs assisted at the Hospital Veterinário/Centro de Saúde e Tecnologia Rural (CSTR/Universidade Federal de Campina Grande (UFCG, Campus de Patos, Paraíba State, Northeastern Brazil. Serological diagnosis of ehrlichiosis was performed by the indirect fluorescent antibody test (IFAT and sera presenting antibody titers >; 40 were considered positive. Of the 109 samples, 72.5% were positive (95% CI = 63.1% - 80.6%. Animals that had contact with other dogs (odds ratio = 3.59; 95% CI = 1.41 - 9.12, contact with ponds (odds ratio = 8.39; 95% CI = 1.01 - 69.87 or with free access to the street (odds ratio = 6.24; 95% CI = 1.28 - 30.39 were more exposed to the risk of infection.

Status report on the folded tandem ion accelerator at BARC

Indian Academy of Sciences (India)

Folded tandem ion accelerator; charged particle beams; voltage stability; Rutherford backscattering; ion optics; beam lines. Abstract. The folded tandem ion accelerator (FOTIA) facility set up at BARC has become operational. At present, it is used for elemental analysis studies using the Rutherford backscattering technique.

Stacking multiple connecting functional materials in tandem organic light-emitting diodes

Science.gov (United States)

Zhang, Tao; Wang, Deng-Ke; Jiang, Nan; Lu, Zheng-Hong

2017-02-01

Tandem device is an important architecture in fabricating high performance organic light-emitting diodes and organic photovoltaic cells. The key element in making a high performance tandem device is the connecting materials stack, which plays an important role in electric field distribution, charge generation and charge injection. For a tandem organic light-emitting diode (OLED) with a simple Liq/Al/MoO3 stack, we discovered that there is a significant current lateral spreading causing light emission over an extremely large area outside the OLED pixel when the Al thickness exceeds 2 nm. This spread light emission, caused by an inductive electric field over one of the device unit, limits one’s ability to fabricate high performance tandem devices. To resolve this issue, a new connecting materials stack with a C60 fullerene buffer layer is reported. This new structure permits optimization of the Al metal layer in the connecting stack and thus enables us to fabricate an efficient tandem OLED having a high 155.6 cd/A current efficiency and a low roll-off (or droop) in current efficiency.

JAERI Tandem annual report 1983

International Nuclear Information System (INIS)

Harada, Kichinosuke; Maruyama, Michio; Okashita, Hiroshi; Ozawa, Kunio; Shikazono, Naomoto; Tanaka, Shigeya

1984-07-01

This annual report describes research activities which have been performed with JAERI tandem accelerator from April 1, 1983 to March 31, 1984. Summary reports of 32 papers, publications, personnel and a list of co-operative reserches with universities are contained. (author)

JAERI tandem annual report, 1982

International Nuclear Information System (INIS)

Harada, Kichinosuke; Maruyama, Michio; Ozawa, Kunio; Shikazono, Naomoto; Tamura, Tsutomu; Tanaka, Shigeya

1983-06-01

This annual report describes research activities which have been performed with JAERI tandem accelerator from September 1, 1981 to March 31, 1983. Summary reports of 38 papers, publications, personnel and a list of co-operative researches with universities are contained. (author)

Cold Climate Heat Pumps Using Tandem Compressors

Energy Technology Data Exchange (ETDEWEB)

Shen, Bo [ORNL; Abdelaziz, Omar [ORNL; Rice, C Keith [ORNL; Baxter, Van D [ORNL

2016-01-01

In cold climate zones, e.g. ASHRAE climate regions IV and V, conventional electric air-source heat pumps (ASHP) do not work well, due to high compressor discharge temperatures, large pressure ratios and inadequate heating capacities at low ambient temperatures. Consequently, significant use of auxiliary strip heating is required to meet the building heating load. We introduce innovative ASHP technologies as part of continuing efforts to eliminate auxiliary strip heat use and maximize heating COP with acceptable cost-effectiveness and reliability. These innovative ASHP were developed using tandem compressors, which are capable of augmenting heating capacity at low temperatures and maintain superior part-load operation efficiency at moderate temperatures. Two options of tandem compressors were studied; the first employs two identical, single-speed compressors, and the second employs two identical, vapor-injection compressors. The investigations were based on system modeling and laboratory evaluation. Both designs have successfully met the performance criteria. Laboratory evaluation showed that the tandem, single-speed compressor ASHP system is able to achieve heating COP = 4.2 at 47 F (8.3 C), COP = 2.9 at 17 F (-8.3 C), and 76% rated capacity and COP = 1.9 at -13 F (-25 C). This yields a HSPF = 11.0 (per AHRI 210/240). The tandem, vapor-injection ASHP is able to reach heating COP = 4.4 at 47 F, COP = 3.1 at 17 F, and 88% rated capacity and COP = 2.0 at -13 F. This yields a HSPF = 12.0. The system modeling and further laboratory evaluation are presented in the paper.

Solution-processed organic tandem solar cells with embedded optical spacers

NARCIS (Netherlands)

Hadipour, Afshin; de Boer, Bert; Blom, Paul W. M.

2007-01-01

We demonstrate a solution-processed polymer tandem solar cell in which the two photoactive single cells are separated by an optical spacer. The use of an optical spacer allows for an independent optimization of both the electronic and optical properties of the tandem cell. The optical transmission

Recombination Is a Major Driving Force of Genetic Diversity in the Anaplasmataceae Ehrlichia ruminantium.

Science.gov (United States)

Cangi, Nídia; Gordon, Jonathan L; Bournez, Laure; Pinarello, Valérie; Aprelon, Rosalie; Huber, Karine; Lefrançois, Thierry; Neves, Luís; Meyer, Damien F; Vachiéry, Nathalie

2016-01-01

The disease, Heartwater, caused by the Anaplasmataceae E. ruminantium , represents a major problem for tropical livestock and wild ruminants. Up to now, no effective vaccine has been available due to a limited cross protection of vaccinal strains on field strains and a high genetic diversity of Ehrlichia ruminantium within geographical locations. To address this issue, we inferred the genetic diversity and population structure of 194 E. ruminantium isolates circulating worldwide using Multilocus Sequence Typing based on lipA, lipB, secY, sodB , and sucA genes . Phylogenetic trees and networks were generated using BEAST and SplitsTree, respectively, and recombination between the different genetic groups was tested using the PHI test for recombination. Our study reveals the repeated occurrence of recombination between E. ruminantium strains, suggesting that it may occur frequently in the genome and has likely played an important role in the maintenance of genetic diversity and the evolution of E. ruminantium . Despite the unclear phylogeny and phylogeography, E. ruminantium isolates are clustered into two main groups: Group 1 (West Africa) and a Group 2 (worldwide) which is represented by West, East, and Southern Africa, Indian Ocean, and Caribbean strains. Some sequence types are common between West Africa and Caribbean and between Southern Africa and Indian Ocean strains. These common sequence types highlight two main introduction events due to the movement of cattle: from West Africa to Caribbean and from Southern Africa to the Indian Ocean islands. Due to the long branch lengths between Group 1 and Group 2, and the propensity for recombination between these groups, it seems that the West African clusters of Subgroup 2 arrived there more recently than the original divergence of the two groups, possibly with the original waves of domesticated ruminants that spread across the African continent several thousand years ago.

Mass spectrometry by means of tandem accelerators

International Nuclear Information System (INIS)

Tuniz, C.

1985-01-01

Mass spectrometry based on an accelerator allows to measure rare cosmogenic isotopes found in natural samples with isotopic abundances up to 10E-15. The XTU Tandem of Legnaro National Laboratories can measure mean heavy isotopes (36Cl, 41Ca, 129I) in applications interesting cosmochronology and Medicine. The TTT-3 Tandem of the Naples University has been modified in view of precision studies of C14 in Archeology, Paleantology and Geology. In this paper a review is made of principles and methodologies and of some applicationy in the framework of the National Program for mass spectrametry research with the aid of accelerators

Tandem electrostatic accelerators for BNCT

International Nuclear Information System (INIS)

Ma, J.C.

1994-01-01

The development of boron neutron capture therapy (BNCT) into a viable therapeutic modality will depend, in part, on the availability of suitable neutron sources compatible with installation in a hospital environment. Low-energy accelerator-based intense neutron sources, using electrostatic or radio frequency quadrupole proton accelerators have been suggested for this purpose and are underdevelopment at several laboratories. New advances in tandem electrostatic accelerator technology now allow acceleration of the multi-milliampere proton beams required to produce therapeutic neutron fluxes for BNCT. The relatively compact size, low weight and high power efficiency of these machines make them particularly attractive for installation in a clinical or research facility. The authors will describe the limitations on ion beam current and available neutron flux from tandem accelerators relative to the requirements for BNCT research and therapy. Preliminary designs and shielding requirements for a tandern accelerator-based BNCT research facility will also be presented

Molecular detection of Ehrlichia canis, Hepatozoon canis and Babesia canis vogeli in stray dogs in Mahasarakham province, Thailand.

Science.gov (United States)

Piratae, Supawadee; Pimpjong, Kiattisak; Vaisusuk, Kotchaphon; Chatan, Wasupon

2015-01-01

Canine tick borne diseases showing distribution worldwide have caused morbidity and mortality in dogs. This study observed the mainly tick borne pathogens described for dogs in Thailand, Ehrlichia canis, Hepatozoon canis and Babesia canis vogeli. From May to July 2014, blood samples were collected from 79 stray dogs from 7 districts of Mahasarakham province to molecular surveyed for 16s rRNA gene of E. canis and 18s rRNA gene of H. canis and B. canis vogeli. Twenty eight (35.44%) of stray dogs showed the infection with tick borne pathogens. The prevalence of E. canis infection was the highest with 21.5% (17/79). DNA of H. canis and B. canis vogeli were detected at the prevalence of 10.1% (8/79) and 6.3% (5/79), respectively. Co-infection between E. canis and B. canis vogeli were identified in 2 (2.5%) dogs. The results indicated that a wide range of tick borne pathogens are circulation in the canine population in Mahasarakham province. This study is the first report on prevalence of E. canis, H. canis and B. canis vogeli in stray dogs in Mahasarakham, a province in northern part of Thailand. This data providing is important to understand the prevalence of E. canis, H. canis and B. canis vogeli infection in stray dogs in this region, which will assist in the management of these blood parasite.

Telemetry component tests in the FN tandem terminal

International Nuclear Information System (INIS)

Bicek, J.J.; Billquis, P.J.; Yntema, J.L.

1977-01-01

When an electrostatic tandem accelerator is used primarily for heavy ion acceleration, numerous communication channels with the high voltage terminal are desirable. The ANL FN tandem operates at a tank pressure of 100 psi SF 6 at terminal voltages up to 9.5 MeV. A low powered He-Ne laser with 15 percent modulation has been successfully tested in the terminal under normal operating conditions. Such a system allows the transmission of information without the use of light guides. Multistranded light guides did not withstand voltage gradients as low as 0.4 MV/m. Single core light guides with a diameter of 0.5 mm have been successfully operated at voltage gradients in excess of 1.7 MV/m. In addition to the laser a microprocessor has also been tested in the tandem terminal. With suitable protection, an 8080 microprocessor and a programmable ROM operated successfully for several weeks under normal operating conditions

Photonic intermediate layer for silicon tandem solar cells

Energy Technology Data Exchange (ETDEWEB)

Bielawny, Andreas; Miclea, Paul-Tiberiu; Wehrspohn, Ralf [Martin-Luther Universitaet Halle-Wittenberg (Germany). Inst. fuer Physik, Mikro-MD; Lee, Seuong-Mo; Knez, Mato [Max-Planck-Inst. fuer Mikrostrukturphysik, Halle (Germany); Carius, Reinhard [Forschungszentrum Juelich (DE). Inst. fuer Photovoltaik (IEF-5); Lisca, Marian; Rockstuhl, Carsten; Lederer, Falk [Universitaet Jena (Germany). Dept. Physik

2008-07-01

The concept of incorporation of a 3D photonic crystal as diffractive spectral filter within a-Si/mc-Si tandem solar cells has been investigated as a promising application. Our intermediate reflective filter enhances the pathway of spectrally selected light within an amorphous silicon top cell in its spectral region of low absorption. From our previous work, we expect a significant improvement of the tandem's efficiency of about 1.2%(absolute). This increases efficiency for a typical silicon tandem cell from 11.2% to 12.4%, as a result of the optical current-matching of the two junctions. Our wavelength-selective optical element is a 3D-structured optical thin-film - prepared by self-organized artificial opal templates and finalized with atomic layer deposition techniques. The resulting samples are highly periodical thin-film inverted opals made of zinc-oxide. We compare recent experimental data on the optical properties with our simulations and photonic bandstructure calculations.

Silicon nanocrystals embedded in silicon carbide for tandem solar cell applications

International Nuclear Information System (INIS)

Schnabel, Manuel

2015-01-01

Tandem solar cells consist of multiple individual solar cells stacked in order of increasing bandgap, with the cell with highest bandgap towards the incident light. This allows photons to be absorbed in the cell that will convert them to electricity with the greatest efficiency, and is the only solar cell concept to surpass the theoretical efficiency limit of a conventional solar cell so far. This work is concerned with the development of silicon nanocrystals (Si NCs) embedded in silicon carbide, which are expected to have a higher bandgap than bulk Si due to quantum confinement, for use in the top cell of a two-junction tandem cell. Charge carrier transport and recombination were investigated as a function of various parameters. Distortion of luminescence spectra by optical interference was highlighted and a robust model to describe transport of majority carriers was developed. Furthermore, a range of processing steps required to produce a Si NC-based tandem cell were studied, culminating in the preparation of the first Si NC-based tandem cells. The resulting cells exhibited open-circuit voltages of 900 mV, demonstrating tandem cell functionality.

IMPACT OF SOME GEOMETRICAL ASPECTS ON THE TANDEM CO-ROTATING PROPELLER HYDRODYNAMIC CHARACTERISTICS

Directory of Open Access Journals (Sweden)

Boucetta Djahida

2017-01-01

Full Text Available In the present paper, a numerical simulation based on Kω-SST turbulence model has been carried out to determine the tandem propeller hydrodynamic characteristics in non-cavitating viscous flow by using the commercial code Fluent. As the first step, the numerical approach has been applied to the case of single propeller and the comparison with experiment results was in a good agreement. Next, the effects of axial and angular displacement as well as the diameter ratio between the tandem propellers have been investigated. This part of the study reveals that the tandem with idem propeller diameters is strongly recommended to assure more advantages. Furthermore, the tandem geometry corresponding to the axial displacement equal to 0.6D seems to be the best configuration and the open water performances remain almost unchanged with the variation of angular displacement. On the other hand, details of the mutual interaction between tandem propellers were also given by showing pressure contours, streamlines and thrust coefficient. Globally, this study illustrates the advantages of replacing single propellers by tandem solution.

TandEM: Titan and Enceladus mission

Science.gov (United States)

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, Christophe; 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, Ji; 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, Catherine 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 (Montgolfière) and possibly several landing probes to be delivered through the atmosphere.

Determination and quantification of the in vitro activity of Aloe marlothii (A. Berger subsp. marlothii and Elephantorrhiza elephantina (Burch. skeels acetone extracts against Ehrlichia ruminantium

Directory of Open Access Journals (Sweden)

V. Naidoo

2006-09-01

Full Text Available An Ehrlichia ruminantium culture system was utilized for the anti-rickettsial evaluation of two ethnoveterinary plants, Elephantorrhiza elephantina and Aloe marlothii. Well-established E. ruminantium cultures were incubated with the plant leaf acetone extracts and compared to oxytetracycline and untreated controls. Effectivity was established by comparing the percentage parasitised cells and the calculation of both EC50 and extrapolated EC90 in µg/ml. The plant extracts were also screened for antibacterial activity using bioautography. Elephantorrhiza elephantina and A. marlothii demonstrated anti-ehrlichial activity with an EC50 of 111.4 and 64.5 µg/ml and EC 90 of 228.9 and 129.9 µg/ml, respectively. The corresponding EC50 and EC90 for oxytetracycline was 0.29 and 0.08 µg/ml. Both plants appeared to produce their inhibitory activity by a similar mechanism, unrelated to that of the tetracyclines. Both the plant acetone extracts demonstrated antibacterial activity against Escherichia coli and Staphylococcus aureus (ATCC strains.

ORNL 25 MV tandem accelerator control system

International Nuclear Information System (INIS)

Juras, R.C.; Biggerstaff, J.A.; Hoglund, D.E.

1985-01-01

The CAMAC-based control system for the 25 MV tandem electrostatic accelerator of the Holifield Heavy Ion Research Facility at Oak Ridge National Laboratory (ORNL) was specified by ORNL and built by the National Electrostatics Corporation. Two Perkin-Elmer 32-bit minicomputers are used in the system, a message switching computer and a supervisory computer. The message switching computer transmits and receives control information on six serial highways. This computer shares memory with the supervisory computer. Operator consoles are located on a serial highway; control is by means of a console CRT, trackball, and assignable shaft encoders and meters. Two identical consoles operate simultaneously: one is located in the tandem control room; the other is located in the cyclotron control room to facilitate operation during injection of tandem beams into the cyclotron or when beam lines under control of the cyclotron control system are used. The supervisory computer is used for accelerator parameter setup calculations, actual accelerator setup for new beams based on scaled, recorded parameters from previously run beams, and various other functions. Nearly seven years of control system operation and improvements will be discussed

Zinc Mediated Tandem Fragmentation-Allylation of Methyl 5-Iodopentofuranosides

DEFF Research Database (Denmark)

Hyldtoft, Lene; Madsen, Robert

1999-01-01

In the presence of zinc and allyl bromide methyl 5-iodopentofuranosides undergo a tandem fragmentation alkylation to give functionalized dienes. These can undergo ring-closing olefin metathesis to produce cyclohexenes which on dihydroxylation give quercitols.......In the presence of zinc and allyl bromide methyl 5-iodopentofuranosides undergo a tandem fragmentation alkylation to give functionalized dienes. These can undergo ring-closing olefin metathesis to produce cyclohexenes which on dihydroxylation give quercitols....

Hybrid tandem quantum dot/organic photovoltaic cells with complementary near infrared absorption

KAUST Repository

Kim, Taesoo; Palmiano, Elenita; Liang, Ru-Ze; Hu, Hanlin; Banavoth, Murali; Kirmani, Ahmad R.; Firdaus, Yuliar; Gao, Yangqin; Sheikh, Arif D.; Yuan, Mingjian; Mohammed, Omar F.; Hoogland, Sjoerd; Beaujuge, Pierre; Sargent, Edward H.; Amassian, Aram

2017-01-01

Monolithically integrated hybrid tandem solar cells that effectively combine solution-processed colloidal quantum dot (CQD) and organic bulk heterojunction subcells to achieve tandem performance that surpasses the individual subcell efficiencies

Analysis of genetic polymorphism of nine short tandem repeat loci in ...

African Journals Online (AJOL)

Yomi

2012-03-15

Mar 15, 2012 ... Key words: short tandem repeat, repeat motif, genetic polymorphism, Han population, forensic genetics. INTRODUCTION. Short tandem repeat (STR) is widely .... Data analysis. The exact test of Hardy-Weinberg equilibrium was conducted with. Arlequin version 3.5 software (Computational and Molecular.

Air-processed organic tandem solar cells on glass: toward competitive operating lifetimes

DEFF Research Database (Denmark)

Adams, Jens; Spyropoulos, George D.; Salvador, Michael

2015-01-01

efficiencies of more than 10% the rather limited stability of this type of devices raises concerns towards future commercialization. The tandem concept allows for both absorbing a broader range of the solar spectrum and reducing thermalization losses. We designed an organic tandem solar cell with an inverted...... device geometry comprising environmentally stable active and charge-selecting layers. Under continuous white light irradiation, we demonstrate an extrapolated, operating lifetime in excess of one decade. We elucidate that for the current generation of organic tandem cells one critical requirement...... for long operating lifetimes consists of periodic UV light treatment. These results suggest that new material approaches towards UV-resilient active and interfacial layers may enable efficient organic tandem solar cells with lifetimes competitive with traditional inorganic photovoltaics....

Accelerator mass spectrometry with a coupled tandem-linac system

International Nuclear Information System (INIS)

Kutschera, W.

1984-01-01

A coupled system provides higher energies, which allows one to extend AMS to hitherto untouched mass regions. Another important argument is that the complexity, although bothersome for the operation, increases the selectivity of detecting a particular isotope. The higher-energy argument holds for any heavy-ion accelerator which is capable of delivering higher energy than a tandem. The present use of tandem-linac combinations for AMS, rather than cyclotrons, linacs or combinations of these machines, has mainly to do with the fact that this technique was almost exclusively developed around tandem accelerators. Therefore the tandem-linac combination is a natural extension to higher energies. The use of negative ions has some particular advantages in suppressing background from unwanted elements that do not form stable negative ions (e.g., N, Mg, Ar). On the other hand, this limits the detection of isotopes to elements which do form negative ions. For particular problems it may therefore be advantageous to use a positive-ion machine. What really matters most for choosing one or the other machine is to what extent the entire accelerator system can be operated in a truly quantiative way from the ion source to the detection system. 20 references, 4 figures

On the Relativistic Correction of Particles Trajectory in Tandem Type Electrostatic Accelerator

Science.gov (United States)

Minárik, Stanislav

2015-08-01

A constant potential is applied to the acceleration of the ion-beam in the tandem type electrostatic accelerator. However, not just one voltage is applied, but instead a number of applications can be made in succession by means of the tandem arrangement of high voltage tubes. This number of voltage applications, which is the number of so-called "stages" of a tandem accelerator, may be two, three, or four, depending on the chosen design. Electrostatic field with approximately constant intensity acts on ions in any stage. In general, non-relativistic dynamics is used for the description of the ion transport in tandem accelerator. Energies of accelerated ions are too low and relativistic effects cannot be commonly observed by standard experimental technique. Estimation of possible relativistic correction of ion trajectories is therefore only a matter of calculation. In this note, we briefly present such calculation. Our aim is to show how using the relativistic dynamics modifies the particles trajectory in tandem type accelerator and what parameters determine this modification.

Axisymmetric tandem mirror stabilized by a magnetic limiter

International Nuclear Information System (INIS)

Kesner, J.; Post, R.S.; Lane, B.

1985-06-01

In order to stabilize MHD-like, fast growing m = 1 fluctuations in the central cell of a tandem mirror we propose the introduction of a magnetic limiter. The magnetic limiter would create a ring null in the magnetic field. Electrons which enter the null can stream azimuthally and thereby ''short-circuit'' m = 1 fluctuations. Some pressure could be maintained on the separatrix flux surface by locating the null on a local magnetic maxima or by axial plugging. This scheme introduces the possibility of a fully axisymmetric tandem mirror

Overview and direction in the tandem mirror program

International Nuclear Information System (INIS)

Thomassen, K.I.

1983-04-01

There are two main thrusts to the tandem mirror program at the present time. One is to gather the experimental data base to verify the axicell thermal-barrier concept and the other to improve the end plugs for tandems. With such improvements one might approach the ideal fusion reactor, a simple solenoid of modular elements whose ends are but a modest perturbation on the configuration from both a cost and technological viewpoint. Progress toward these two goals is discussed here, and the directions to be taken in the immediate future are described

Development of an advanced spacecraft tandem mass spectrometer

Science.gov (United States)

Drew, Russell C.

1992-03-01

The purpose of this research was to apply current advanced technology in electronics and materials to the development of a miniaturized Tandem Mass Spectrometer that would have the potential for future development into a package suitable for spacecraft use. The mass spectrometer to be used as a basis for the tandem instrument would be a magnetic sector instrument, of Nier-Johnson configuration, as used on the Viking Mars Lander mission. This instrument configuration would then be matched with a suitable second stage MS to provide the benefits of tandem MS operation for rapid identification of unknown organic compounds. This tandem instrument is configured with a newly designed GC system to aid in separation of complex mixtures prior to MS analysis. A number of important results were achieved in the course of this project. Among them were the development of a miniaturized GC subsystem, with a unique desorber-injector, fully temperature feedback controlled oven with powered cooling for rapid reset to ambient conditions, a unique combination inlet system to the MS that provides for both membrane sampling and direct capillary column sample transfer, a compact and ruggedized alignment configuration for the MS, an improved ion source design for increased sensitivity, and a simple, rugged tandem MS configuration that is particularly adaptable to spacecraft use because of its low power and low vacuum pumping requirements. The potential applications of this research include use in manned spacecraft like the space station as a real-time detection and warning device for the presence of potentially harmful trace contaminants of the spacecraft atmosphere, use as an analytical device for evaluating samples collected on the Moon or a planetary surface, or even use in connection with monitoring potentially hazardous conditions that may exist in terrestrial locations such as launch pads, environmental test chambers or other sensitive areas. Commercial development of the technology

On the Relativistic Correction of Particles Trajectory in Tandem Type Electrostatic Accelerator

OpenAIRE

Minárik Stanislav

2015-01-01

A constant potential is applied to the acceleration of the ion-beam in the tandem type electrostatic accelerator. However, not just one voltage is applied, but instead a number of applications can be made in succession by means of the tandem arrangement of high voltage tubes. This number of voltage applications, which is the number of so-called "stages" of a tandem accelerator, may be two, three, or four, depending on the chosen design. Electrostatic field with approximately constant intensit...

Status of tandem mirror theory

International Nuclear Information System (INIS)

Baldwin, D.E.

1979-01-01

This report contains the text and slides used for the review talk on tandem mirror theory presented at the meeting of the Division of Plasma Physics, A.P.S., Boston, MA, November 12-16, 1979. Topics covered include classical confinement, equilibria, MHD- and micro-stability, radial transport, and thermal barriers

Design and long-term monitoring of DSC/CIGS tandem solar module

International Nuclear Information System (INIS)

Vildanova, M F; Nikolskaia, A B; Kozlov, S S; Shevaleevskiy, O I

2015-01-01

This paper describes the design and development of tandem dye-sensitized/Cu(In, Ga)Se (DSC/CIGS) PV modules. The tandem PV module comprised of the top DSC module and a bottom commercial 0,8 m 2 CIGS module. The top DSC module was made of 10 DSC mini-modules with the field size of 20 × 20 cm 2 each. Tandem DSC/CIGS PV modules were used for providing the long-term monitoring of energy yield and electrical parameters in comparison with standalone CIGS modules under outdoor conditions. The outdoor test facility, containing solar modules of both types and a measurement unit, was located on the roof of the Institute of Biochemical Physics in Moscow. The data obtained during monitoring within the 2014 year period has shown the advantages of the designed tandem DSC/CIGS PV-modules over the conventional CIGS modules, especially for cloudy weather and low-intensity irradiation conditions. (paper)

Single P-N junction tandem photovoltaic device

Science.gov (United States)

Walukiewicz, Wladyslaw [Kensington, CA; Ager, III, Joel W.; Yu, Kin Man [Lafayette, CA

2011-10-18

A single P-N junction solar cell is provided having two depletion regions for charge separation while allowing the electrons and holes to recombine such that the voltages associated with both depletion regions of the solar cell will add together. The single p-n junction solar cell includes an alloy of either InGaN or InAlN formed on one side of the P-N junction with Si formed on the other side in order to produce characteristics of a two junction (2J) tandem solar cell through only a single P-N junction. A single P-N junction solar cell having tandem solar cell characteristics will achieve power conversion efficiencies exceeding 30%.

Major maintenance of the Munich MP-tandem

International Nuclear Information System (INIS)

Muenzer, H.; Carli, W.; Hartung, P.; Jakob, H.; Nocker, H.; Rohrer, L.; Schnitter, H.; Assmann, W.; Maier, H.J.; Machlitt, N.; Steffens, H.

1988-01-01

Several measures have been taken to restore the voltage performance of the Munich tandem. 1. All accelerator tubes were reconditioned by sandblasting, new electrodes and diaphragms were inserted and preassembled groups of tubes were baked in high vacuum. 2. All other vacuum components were cleaned, baked in high vacuum and partly pressure leak tested outside the tandem. 3. High voltage tests were performed with tubes. Without portico voltages up to 16 MV were obtained, with portico up to 17.5 MV. 4. Some modifications (e.g. infrared light links) were introduced. The shutdown lasted 6 months. In March 1987 beam operation was resumed at moderate terminal voltages, interrupted by intervals of soft conditioning. (orig.)

Feedback stabilized tandem Fabry-Perot interferometer

International Nuclear Information System (INIS)

Fukushima, Hiroyuki; Ito, Mikio; Shirasu, Hiroshi.

1986-01-01

A new system for measuring the isotopic ratio of uranium, in which two plane-type Fabry-Perot interferometers (tandem FP) are connected in series. The parallelism between the two FPs is achieved automatically by a feedback control mechanism based on laser interference fringe monitoring. The structure of the tandem FP, feedback control system, automatic parallelism adjustment mechanism and wavelength synchronization mechanism are described in detail. For experiments, a hollow cathode discharge tube of a pulse discharge type is employed. Measurements are made to determine the effects of pulse width on the 238 U peak height of 502.7 nm line, recorder traces of 235 U and 238 U lines, half width for 238 U component of the 502.7 nm line, SN ratio, reproducibility of the 235 U/ 238 U peak height ratio and 235 U/ 238 U intensity ratio. Considerations are made on the spectral line width, contrast, transmission factor, and stability of automatic parallelism control and wavelength synchronization. Results obtained indicates that a single-type interferometer would serve adequately for measuring the 235 U/ 238 U ratio if the automatic parallelism control developed here is used. The ultimate object of the tandem system is to make measurement of 236 U. Satisfactory results have not obtained as yet, but most likely the present system would make it possible if a light source of a higher intensity and advanced photometric techniques are developed. (Nogami, K.)

Status of the Catania tandem as injector of the superconducting cyclotron

International Nuclear Information System (INIS)

Ciavola, G.; Cuttone, G.; Raia, G.

1990-01-01

The Catania LNS tandem facility is operating since 1984. The status and the main modifications of the accelerator during these years are described and the performance obtained is reported. A superconducting cyclotron will be installed at the LNS facility as tandem booster; the main progress is presented. (orig.)

Dinuclear Tetrapyrazolyl Palladium Complexes Exhibiting Facile Tandem Transfer Hydrogenation/Suzuki Coupling Reaction of Fluoroarylketone

KAUST Repository

Dehury, Niranjan

2016-07-18

Herein, we report an unprecedented example of dinuclear pyrazolyl-based Pd complexes exhibiting facile tandem catalysis for fluoroarylketone: Tetrapyrazolyl di-palladium complexes with varying Pd-Pd distances efficiently catalyze the tandem reaction involving transfer hydrogenation of fluoroarylketone to the corresponding alcohol and Suzuki-Miyaura cross coupling reaction of the resulting fluoroarylalcohol under moderate reaction conditions, to biaryl alcohol. The complex with the shortest Pd-Pd distance exhibits the highest tandem activity among its di-metallic analogues, and exceeds in terms of activity and selectivity the analogous mononuclear compound. The kinetics of the reaction indicates clearly that reductive transformation of haloarylketone into haloaryalcohol is the rate determining step in the tandem reaction. Interestingly while fluoroarylketone undergoes the multistep tandem catalysis, the chloro- and bromo-arylketones undergo only a single step C-C coupling reaction resulting in biarylketone as the final product. Unlike the pyrazole based Pd compounds, the precursor PdCl2 and the phosphine based relevant complexes (PPh3)2PdCl2 and (PPh3)4Pd are found to be unable to exhibit the tandem catalysis.

Accelerator mass analysis at tandem accelerator in Kyoto University

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Masanobu; Tazawa, Yuji; Matsumoto, Hiroshi; Hirose, Masanori [Kyoto Univ. (Japan). Faculty of Science; Ogino, Koya; Kohno, Masuchika; Funaba, Hiroyuki

1996-12-01

Tandem accelerator in Science Faculty, Kyoto University was renewed from 5 MV in the highest terminal voltage of Van de Graaff to 8 MV of Peletron in 1992. And, AMS effective for cosmic ray, dating, environment measurement and so forth is determined to a column of collaborative studies by universities and institutes in Japan. On this renewal, because of using high energy beam transportation of the present tandem accelerator, super high sensitivity measurement of long half-life radioactive isotopes of heavy elements such as {sup 36}Cl, {sup 41}Ca, {sup 129}I and so forth is aimed, although having some limitations due to small magnet. The accelerator is active in characteristics of the middle size tandem accelerator, and developing {sup 14}C measurement for its standard technology, as aiming at {sup 36}Cl measurement, at first. As a result, in this tandem accelerator stable and high beam transmittance could be obtained by adding a slit at negative ion source to make emittance of incident beam smaller. {sup 14}C/{sup 12}C ratio of Modan`s sample obtained by graphitizing NBS oxalic acid and Ded`s sample consisting of mineral graphite produced in Sri Lanka are measured to confirm better reproductivity of this system. Future development of successive incident method is planned to test actual carbon samples. (G.K.)

Determination of 5-fluorouracil in plasma with HPLC-tandem mass spectrometry

NARCIS (Netherlands)

van Kuilenburg, A. B. P.; van Lenthe, H.; Maring, J. G.; van Gennip, A. H.

2006-01-01

In this article, we describe a fast and specific method to measure 5FU with HPLC tandem-mass spectrometry. Reversed-phase HPLC was combined with electrospray ionization tandem mass spectrometry and detection was performed by multiple-reaction monitoring. Stable-isotope-labeled 5FU (1,3-15N2-5FU) was

Hybrid tandem quantum dot/organic photovoltaic cells with complementary near infrared absorption

KAUST Repository

Kim, Taesoo

2017-06-01

Monolithically integrated hybrid tandem solar cells that effectively combine solution-processed colloidal quantum dot (CQD) and organic bulk heterojunction subcells to achieve tandem performance that surpasses the individual subcell efficiencies have not been demonstrated to date. In this work, we demonstrate hybrid tandem cells with a low bandgap PbS CQD subcell harvesting the visible and near-infrared photons and a polymer:fullerene—poly (diketopyrrolopyrrole-terthiophene) (PDPP3T):[6,6]-phenyl-C60-butyric acid methyl ester (PC61BM)—top cell absorbing effectively the red and near-infrared photons of the solar spectrum in a complementary fashion. The two subcells are connected in series via an interconnecting layer (ICL) composed of a metal oxide layer, a conjugated polyelectrolyte, and an ultrathin layer of Au. The ultrathin layer of Au forms nano-islands in the ICL, reducing the series resistance, increasing the shunt resistance, and enhancing the device fill-factor. The hybrid tandems reach a power conversion efficiency (PCE) of 7.9%, significantly higher than the PCE of the corresponding individual single cells, representing one of the highest efficiencies reported to date for hybrid tandem solar cells based on CQD and polymer subcells.

Modelling of tandem cell temperature coefficients

Energy Technology Data Exchange (ETDEWEB)

Friedman, D.J. [National Renewable Energy Lab., Golden, CO (United States)

1996-05-01

This paper discusses the temperature dependence of the basic solar-cell operating parameters for a GaInP/GaAs series-connected two-terminal tandem cell. The effects of series resistance and of different incident solar spectra are also discussed.

On the Relativistic Correction of Particles Trajectory in Tandem Type Electrostatic Accelerator

Directory of Open Access Journals (Sweden)

Minárik Stanislav

2015-08-01

Full Text Available A constant potential is applied to the acceleration of the ion-beam in the tandem type electrostatic accelerator. However, not just one voltage is applied, but instead a number of applications can be made in succession by means of the tandem arrangement of high voltage tubes. This number of voltage applications, which is the number of so-called "stages" of a tandem accelerator, may be two, three, or four, depending on the chosen design. Electrostatic field with approximately constant intensity acts on ions in any stage.

Simulation of tandem hydrofoils by finite volume method with moving grid system; Henkei koshi wo tsukatta yugen taisekiho ni yoru tandem suichuyoku no simulation

Energy Technology Data Exchange (ETDEWEB)

Kawashima, H. [Ship Research Inst., Tokyo (Japan); Miyata, H. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering

1996-12-31

With an objective to clarify possibility of application of time-advancing calculated fluid dynamic (CFD) simulation by using a finite volume method with moving grid system, a simulation was performed on motion of a ship with hydrofoils including the control system therein. The simulation consists of a method that couples a moving grid system technology, an equation of motion, and the control system. Complex interactions between wings and with free surface may be considered automatically by directly deriving fluid force from a flow field by using the CFD. In addition, two-dimensional flows around tandem hydrofoils were calculated to solve the motion problem within a vertical plane. As a result, the following results were obtained: a finite volume method using a dynamic moving grid system method was applied to problems in non-steady tandem hydrofoils to show its usefulness; a method that couples the CFD with the equation of motion was applied to the control problems in the tandem hydrofoils to show possibility of a new technology for simulating motions; and a simulation that considers such wing interference as wave creation, discharged vortices, and associated flows was shown useful to understand characteristics of the tandem hydrofoils. 13 refs., 14 figs.

Tandem photovoltaic solar cells and increased solar energy conversion efficiency

Science.gov (United States)

Loferski, J. J.

1976-01-01

Tandem photovoltaic cells, as proposed by Jackson (1955) to increase the efficiency of solar energy conversion, involve the construction of a system of stacked p/n homojunction photovoltaic cells composed of different semiconductors. It had been pointed out by critics, however, that the total power which could be extracted from the cells in the stack placed side by side was substantially greater than the power obtained from the stacked cells. A reexamination of the tandem cell concept in view of the development of the past few years is conducted. It is concluded that the use of tandem cell systems in flat plate collectors, as originally envisioned by Jackson, may yet become feasible as a result of the development of economically acceptable solar cells for large scale terrestrial power generation.

The PSI/ETH tandem accelerator facility

Energy Technology Data Exchange (ETDEWEB)

Synal, H.A.; Doebeli, M.; Fuhrmann, H.; Kubik, P.W.; Nebiker, P.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)] [and others

1997-09-01

The 1996 operation of the PSI/ETH tandem accelerator at ETH Hoenggerberg is summarised with a detailed compilation of the beam time statistics and the statistics of AMS samples for the different radioisotopes and for the major fields of research. (author) 2 tab.

Current results of the tandem mirror experiment

International Nuclear Information System (INIS)

Drake, R.P.

1980-01-01

The basic operating characteristics of the Tandem Mirror Experiment, (TMX) at the Lawrence Livermore Laboratory in the USA have been established. Tandem-mirror plasmas have been produced using neutral-beam-fueled end plugs and a gas-fueled center cell. An axial potential well between the end plugs has been measured. There is direct evidence that this potential well enhances the axial confinement of the center-cell ions. The observed densities and loss currents are consistent with preliminary studies of the particle sources and losses near the magnetic axis. The observed confinement is consistent with theory when plasma fluctuations are low. When the requirement of drift-cyclotron loss-cone mode stability is violated, the plasma fluctuations degrade the center-cell confinement

Present status of tandem accelerator in Japan Atomic Energy Research Institute

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Tadashi; Kanda, Susumu; Takeuchi, Suehiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1996-12-01

The tandem accelerator in Japan Atomic Energy Research Institute was made by NEC in USA. Since it is the accelerator of turning-up structure, it has large magnet at the high voltage terminal, and supplies electric power by driving a generator with large diameter shaft. The control is carried out by CAMUCK, and the electronic circuit is protected from the surging arising due to discharge. Since the experiment on full scale was begun, 14 years have elapsed, and at present, it became a very stable accelerator. As to the operation mode, the acceleration voltage is limited to below 17 MV. The operation voltage and the state of operation are shown. Recently, the troubles of chains originating in oil have occurred. The adjustment of the tandem accelerator requires more than one month. The adjustment is mainly related to the chains and shafts, and this is explained. The ion source used for the tandem accelerator at present is the negative ion source made by NEC. The installation of an ECR ion source is planned. The utilization of the tandem accelerator system is reported. (K.I.)

Solution processed organic bulk heterojunction tandem solar cells

Energy Technology Data Exchange (ETDEWEB)

Albrecht, Steve; Neher, Dieter [Soft Matter Physics, University of Potsdam, D-14476 Potsdam (Germany)

2011-07-01

One of the critical issues regarding the preparation of organic tandem solar cells from solution is the central recombination contact. This contact should be highly transparent and conductive to provide high recombination currents. Moreover it should protect the 1st subcell from the solution processing of the 2nd subcell. Here, we present a systematic study of various recombination contacts in organic bulk heterojunction tandem solar cells made from blends of different polymers with PCBM. We compare solution processed recombination contacts fabricated from metal-oxides (TiO{sub 2} and ZnO) and PEDOT:PSS with evaporated recombination contacts made from thin metal layers and molybdenum-oxide. The solar cell characteristics as well as the morphology of the contacts measured by AFM and SEM are illustrated. To compare the electrical properties of the varying contacts we show measurements on single carrier devices for different contact-structures. Alongside we present the results of optical modeling of the subcells and the complete tandem device and relate these results to experimental absorption and reflection spectra of the same structures. Based on these studies, layer thicknesses were adjusted for optimum current matching and device performance.

Workshop of the JAEA-Tokai Tandem Accelerator. Memorial of 100,000-hour operation

International Nuclear Information System (INIS)

Ishii, Tetsuro; Osa, Akihiko

2009-04-01

Workshop of the JAEA-Tokai tandem accelerator has been held every two years. As a memorial of 100,000-hour operation of the tandem accelerator, we have organized the workshop focusing on the activity at this facility. This workshop covers developments and experiments carried out so far, together with experiments in progress and proposals in future. As previous series of workshops, we offered an opportunity to have active discussion among scientists in different fields including accelerator, nuclear physics, nuclear chemistry, radiation effects, atomic physics and so on, aiming at extending facility and research interactively. As a memorial lecture, we invited Dr. Akira Tonomura of fellow of Hitachi, Ltd, a distinctive scientist for development of electron holography. He delivered a lecture titled 'Structure of magnetic flux observed by electron beam'. He once used the tandem accelerator to induce columnar defects in high-temperature superconductor and studied vortices trapped along the defects. Prof. Shigeru Kubono of University of Tokyo, a chairman of program advisory committee of the tandem accelerator, encouraged us through a talk of 'Expectations for the JAEA-Tokai tandem accelerator'. This workshop was held at Advanced Science Research Center Building in Nuclear Science Research Institute on January 6th and 7th in 2009, having 24 oral presentations and 48 posters, and successfully carried out with as many as 120 participants and a lot of science discussions. This review is the collection of slides of oral presentations. The colored slides can be also found in the home page of the tandem accelerator facility (http://rrsys.tokai-sc.jaea.go.jp/rrsys/html/tandem/index.html). (author)

Roll-to-roll processed polymer tandem solar cells partially processed from water

DEFF Research Database (Denmark)

Larsen-Olsen, Thue Trofod; Andersen, Thomas Rieks; Andreasen, Birgitta

2012-01-01

Large area polymer tandem solar cells completely processed using roll-to-roll (R2R) coating and printing techniques are demonstrated. A stable tandem structure was achieved by the use of orthogonal ink solvents for the coating of all layers, including both active layers. Processing solvents...... included water, alcohols and chlorobenzene. Open-circuit voltages close to the expected sum of sub cell voltages were achieved, while the overall efficiency of the tandem cells was found to be limited by the low yielding back cell, which was processed from water based ink. Many of the challenges associated...

Rhodium-Biphephos-Catalyzed Tandem Isomerization–Hydroformylation of Oleonitrile

Directory of Open Access Journals (Sweden)

Lucas Le Goanvic

2018-01-01

Full Text Available Tandem isomerization–hydroformylation of oleonitrile (an 18-carbon nitrile with a remote internal (9-C=C bond has been studied using Rh-bisphosphite catalyst systems, targeting formation of the linear aldehyde. The best compromise between regioselectivity (l/b = 58:42 and chemoselectivity (60% was obtained at 120 °C and 10 bar CO/H2 (1:1 with a catalyst based on Biphephos at a 0.5 mol % catalyst load and a low ligand excess (2 equiv. versus Rh. These values stand among the better reported ones for the tandem isomerization–hydroformylation of long chain olefins with a single-component catalyst system.

Tunable color parallel tandem organic light emitting devices with carbon nanotube and metallic sheet interlayers

Energy Technology Data Exchange (ETDEWEB)

Oliva, Jorge; Desirena, Haggeo; De la Rosa, Elder [Centro de Investigaciones en Optica, A.P. 1-948, León, Guanajuato 37160 (Mexico); Papadimitratos, Alexios [Solarno Inc., Coppell, Texas 75019 (United States); University of Texas at Dallas, Richardson, Texas 75080 (United States); Zakhidov, Anvar A., E-mail: Zakhidov@utdallas.edu [Solarno Inc., Coppell, Texas 75019 (United States); University of Texas at Dallas, Richardson, Texas 75080 (United States); Energy Efficiency Center, National University of Science and Technology, MISiS, Moscow 119049 (Russian Federation)

2015-11-21

Parallel tandem organic light emitting devices (OLEDs) were fabricated with transparent multiwall carbon nanotube sheets (MWCNT) and thin metal films (Al, Ag) as interlayers. In parallel monolithic tandem architecture, the MWCNT (or metallic films) interlayers are an active electrode which injects similar charges into subunits. In the case of parallel tandems with common anode (C.A.) of this study, holes are injected into top and bottom subunits from the common interlayer electrode; whereas in the configuration of common cathode (C.C.), electrons are injected into the top and bottom subunits. Both subunits of the tandem can thus be monolithically connected functionally in an active structure in which each subunit can be electrically addressed separately. Our tandem OLEDs have a polymer as emitter in the bottom subunit and a small molecule emitter in the top subunit. We also compared the performance of the parallel tandem with that of in series and the additional advantages of the parallel architecture over the in-series were: tunable chromaticity, lower voltage operation, and higher brightness. Finally, we demonstrate that processing of the MWCNT sheets as a common anode in parallel tandems is an easy and low cost process, since their integration as electrodes in OLEDs is achieved by simple dry lamination process.

Technical specification for a 25 MV tandem electrostatic accelerator

International Nuclear Information System (INIS)

Jones, C.M.; Biggerstaff, J.A.; Blair, J.K.; Ball, J.B.; Larson, J.D.; Martin, J.A.; McConnell, J.W.; Milner, W.T.; Murray, J.A.; Ziegler, N.F.

1975-08-01

Specifications are given for an accelerator system to consist of a 25 MV tandem electrostatic accelerator and specified ancillary equipment, including an injector, a beam transport system, a vacuum system, a control system, and a system for storage of the insulating gas and transport of the gas to and from the accelerator. The insulating gas shall be SF 6 . The tandem electrostatic accelerator shall be vertical in orientation and of folded construction, and shall be installed in a new structure adjacent to the Oak Ridge Isochronous Cyclotron. (auth)

New uses for the Tandem Van de Graaff Accelerator

International Nuclear Information System (INIS)

Balcazar Garcia, M.

1989-01-01

The Tandem Van de Graaff is a very high resolution magnetic separator whose application offers a rich and virgin field for research in other areas. This work presents some of the radioisotopes of interest; their mechanisms of formation and this relationship with studies in solar activity variations in earth magnetic fields, carbon cycle dynamics, archaeological dating, dating of aquifer deposits, solar influences on variations in earth climates and the mechanics of tectonic plates. Discussed are the advantages of the Tandem utilization as an isotope separator compared with conventional techniques. (Author)

Ohio University tandem Van de Graaff accelerator. Final report

International Nuclear Information System (INIS)

Lane, R.O.

1977-11-01

A summary is given of the work carried out at the John Edwards Tandem Accelerator Laboratory of Ohio University during the period 1970 to 1977 on studies of neutron-nucleus interactions and nuclear structure using neutrons as probes. This work utilizes the main and unique characteristic of the accelerator: high current, high voltage tandem. Certain applied areas were also studied, such as the production of short-lived isotopes for use in medical diagnoses, production of very high neutron intensity to observe possible sputtering effects, and proton induced x-ray emission with a microprobe beam

Improved Optics in Monolithic Perovskite/Silicon Tandem Solar Cells with a Nanocrystalline Silicon Recombination Junction

KAUST Repository

Sahli, Florent

2017-10-09

Perovskite/silicon tandem solar cells are increasingly recognized as promi­sing candidates for next-generation photovoltaics with performance beyond the single-junction limit at potentially low production costs. Current designs for monolithic tandems rely on transparent conductive oxides as an intermediate recombination layer, which lead to optical losses and reduced shunt resistance. An improved recombination junction based on nanocrystalline silicon layers to mitigate these losses is demonstrated. When employed in monolithic perovskite/silicon heterojunction tandem cells with a planar front side, this junction is found to increase the bottom cell photocurrent by more than 1 mA cm−2. In combination with a cesium-based perovskite top cell, this leads to tandem cell power-conversion efficiencies of up to 22.7% obtained from J–V measurements and steady-state efficiencies of up to 22.0% during maximum power point tracking. Thanks to its low lateral conductivity, the nanocrystalline silicon recombination junction enables upscaling of monolithic perovskite/silicon heterojunction tandem cells, resulting in a 12.96 cm2 monolithic tandem cell with a steady-state efficiency of 18%.

Improved Optics in Monolithic Perovskite/Silicon Tandem Solar Cells with a Nanocrystalline Silicon Recombination Junction

KAUST Repository

Sahli, Florent; Kamino, Brett A.; Werner, Jé ré mie; Brä uninger, Matthias; Paviet-Salomon, Bertrand; Barraud, Loris; Monnard, Raphaë l; Seif, Johannes Peter; Tomasi, Andrea; Jeangros, Quentin; Hessler-Wyser, Aï cha; De Wolf, Stefaan; Despeisse, Matthieu; Nicolay, Sylvain; Niesen, Bjoern; Ballif, Christophe

2017-01-01

Perovskite/silicon tandem solar cells are increasingly recognized as promi­sing candidates for next-generation photovoltaics with performance beyond the single-junction limit at potentially low production costs. Current designs for monolithic tandems rely on transparent conductive oxides as an intermediate recombination layer, which lead to optical losses and reduced shunt resistance. An improved recombination junction based on nanocrystalline silicon layers to mitigate these losses is demonstrated. When employed in monolithic perovskite/silicon heterojunction tandem cells with a planar front side, this junction is found to increase the bottom cell photocurrent by more than 1 mA cm−2. In combination with a cesium-based perovskite top cell, this leads to tandem cell power-conversion efficiencies of up to 22.7% obtained from J–V measurements and steady-state efficiencies of up to 22.0% during maximum power point tracking. Thanks to its low lateral conductivity, the nanocrystalline silicon recombination junction enables upscaling of monolithic perovskite/silicon heterojunction tandem cells, resulting in a 12.96 cm2 monolithic tandem cell with a steady-state efficiency of 18%.

Critical analysis of vector-borne infections in dogs: Babesia vogeli, Babesia gibsoni, Ehrlichia canis and Hepatozoon canis in Punjab, India.

Science.gov (United States)

Singla, Lachhman Das; Sumbria, Deepak; Mandhotra, Ajay; Bal, M S; Kaur, Paramjit

2016-12-01

There are few published studies on various vector borne diseases of dogs in India and most depict clinical infection in dogs, diagnosed by observation of the haemopathogens in stained blood smears. This study provides the first report regarding molecular confirmation and ancestral relationship analysis of blood smears positive cases of assorted haemopathogens in Punjab province of India. On blood smear examination, haemopathogens were observed in 124 out of 778 (15.95%, 95% CI: 13.53- 18.68) blood smears. Further polymerase chain reactions (PCR) was used on bloods smear positive cases to validate the results. Out of 778 blood samples, Babesia gibsoni was most common parasite infecting dogs (15.04%, 95% CI: 12.7-17.72), followed by Ehrlichia canis (0.39%, 95% CI: 0.0-1.13), infection of Babesia vogeli and Hepatozoon canis was same (0.26%, 95% CI: 0.0-0.9). Among various risk factors studied (age, sex, season), prevalence of infection was non-significantly higher in 1-2 year of age group (19.88%, 95% CI: 14.45-26.71), regarding sex same prevalence was recorded (15.94%), and chances of infection was highest in pre-monsoon i.e. summer (18.26%, 95% CI: 14.49-22.76). Phylogenetic analysis revealed ancestral background of Ludhiana isolates of B. vogeli, B. gibsoni, H. canis, and E. canis with the isolates of Philippines, Mongolia and Tunisia.

Tandem-ESQ for accelerator-based BNCT

International Nuclear Information System (INIS)

Kreiner, A.J.; Burlon, A.A.; Di Paolo, H.; Minsky, D.M.; Valda, A.A.; Debray, M.E.; Somacal, H.R.; Kwan, J.W.; Henestroza, E.

2006-01-01

A project to develop a Tandem-ElectroStatic-Quadrupole (TESQ) accelerator for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT) is described. A folded tandem, with 1.25 MV terminal voltage, combined with an ElectroStatic Quadrupole (ESQ) chain is being proposed. The project goal is a machine capable of delivering 30 mA of 2.5 MeV protons to be used in conjunction with a neutron production target based on the 7 Li(p,n) 7 Be reaction beyond its resonance at 2.25 MeV. This machine is conceptually shown to be capable of accelerating a 30 mA proton beam to 2.5 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the '7Li(p,n) 7 Be reaction, to perform BNCT treatment for deep-seated tumors in less than an hour. This electrostatic machine is the technologically simplest and cheapest solution for optimized AB-BNCT. (author)

UV-induced tandem double mutations in the trpA gene of E. coli

International Nuclear Information System (INIS)

Piechocki, R.; Langhammer, R.

1980-01-01

The ultraviolet light induction of tandem double mutations in a reverse mutation system was shown using trpA mutants which are characterized by the codon sequences GAA and AAG in codon position 211. Among 597 Trp + independent revertants of the trpA (AAG211) strain 3 full revertants were detected arising from UV-induced tandem double base exchanges. In the codon unit 211 full revertants due to single base exchanges are at least 20 times as frequent as full revertants due to tandem double base exchanges. (author)

Flexible and fragmentable tandem photosensitive nanocrystal skins

Science.gov (United States)

Akhavan, S.; Uran, C.; Bozok, B.; Gungor, K.; Kelestemur, Y.; Lesnyak, V.; Gaponik, N.; Eychmüller, A.; Demir, H. V.

2016-02-01

We proposed and demonstrated the first account of large-area, semi-transparent, tandem photosensitive nanocrystal skins (PNSs) constructed on flexible substrates operating on the principle of photogenerated potential buildup, which avoid the need for applying an external bias and circumvent the current-matching limitation between junctions. We successfully fabricated and operated the tandem PNSs composed of single monolayers of colloidal water-soluble CdTe and CdHgTe nanocrystals (NCs) in adjacent junctions on a Kapton polymer tape. Owing to the usage of a single NC layer in each junction, noise generation was significantly reduced while keeping the resulting PNS films considerably transparent. In each junction, photogenerated excitons are dissociated at the interface of the semi-transparent Al electrode and the NC layer, with holes migrating to the contact electrode and electrons trapped in the NCs. As a result, the tandem PNSs lead to an open-circuit photovoltage buildup equal to the sum of those of the two single junctions, exhibiting a total voltage buildup of 128.4 mV at an excitation intensity of 75.8 μW cm-2 at 350 nm. Furthermore, we showed that these flexible PNSs could be bent over 3.5 mm radius of curvature and cut out in arbitrary shapes without damaging the operation of individual parts and without introducing any significant loss in the total sensitivity. These findings indicate that the NC skins are promising as building blocks to make low-cost, flexible, large-area UV/visible sensing platforms with highly efficient full-spectrum conversion.We proposed and demonstrated the first account of large-area, semi-transparent, tandem photosensitive nanocrystal skins (PNSs) constructed on flexible substrates operating on the principle of photogenerated potential buildup, which avoid the need for applying an external bias and circumvent the current-matching limitation between junctions. We successfully fabricated and operated the tandem PNSs composed of

Life cycle analysis of organic tandem solar cells: When are they warranted?

DEFF Research Database (Denmark)

Espinosa Martinez, Nieves; Krebs, Frederik C

2014-01-01

in their making when compared with the single junction solar cell has to be justified and compensated by a higher efficiency. A central question to ask is how much energy you need to invest in a system in order for it to produce energy and return the investment at least once and preferably a number of times....... As an initial investigation into the potential viability of the tandem or multi-junction approach we have engaged in a detailed analysis based on the manufacturing energy for each step within the tandem module supply chain for full ambient processing of thin flexible polymer tandem solar cells prepared entirely...

Simulation of Two Dimensional Electrophoresis and Tandem Mass Spectrometry for Teaching Proteomics

Science.gov (United States)

Fisher, Amanda; Sekera, Emily; Payne, Jill; Craig, Paul

2012-01-01

In proteomics, complex mixtures of proteins are separated (usually by chromatography or electrophoresis) and identified by mass spectrometry. We have created 2DE Tandem MS, a computer program designed for use in the biochemistry, proteomics, or bioinformatics classroom. It contains two simulations--2D electrophoresis and tandem mass spectrometry.…

Exploring dark current voltage characteristics of micromorph silicon tandem cells with computer simulations

NARCIS (Netherlands)

Sturiale, A.; Li, H. B. T.; Rath, J.K.; Schropp, R.E.I.; Rubinelli, F.A.

2009-01-01

The transport mechanisms controlling the forward dark current-voltage characteristic of the silicon micromorph tandem solar cell were investigated with numerical modeling techniques. The dark current-voltage characteristics of the micromorph tandem structure at forward voltages show three regions:

Dinuclear Tetrapyrazolyl Palladium Complexes Exhibiting Facile Tandem Transfer Hydrogenation/Suzuki Coupling Reaction of Fluoroarylketone

KAUST Repository

Dehury, Niranjan; Maity, Niladri; Tripathy, Suman Kumar; Basset, Jean-Marie; Patra, Srikanta

2016-01-01

Herein, we report an unprecedented example of dinuclear pyrazolyl-based Pd complexes exhibiting facile tandem catalysis for fluoroarylketone: Tetrapyrazolyl di-palladium complexes with varying Pd-Pd distances efficiently catalyze the tandem reaction

Photoemission spectroscopy study on interfacial energy level alignments in tandem organic light-emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Ou, Qing-Dong; Li, Chi; Li, Yan-Qing, E-mail: yqli@suda.edu.cn; Tang, Jian-Xin, E-mail: jxtang@suda.edu.cn

2015-10-01

Highlights: • The interface energetics of tandem OLEDs is overviewed. • Energy level alignment in CGLs is addressed via photoemission spectroscopy. • The n-type doping effect with cesium compounds is discussed. • Hole injection barrier is dependent on oxygen vacancies in transition metal oxides. • Device lifetime of tandem OLEDs is sensitive to interfacial stability of CGLs. - Abstract: Organic light-emitting diodes (OLEDs) using a tandem structure offer a highly attractive option for the applications of next-generation flat panel displays and solid-state lighting due to the extremely high brightness and efficiency along with the long operational lifetime. In general, reliable information about interface energetics of the charge generation layers (CGLs), which plays the central role in charge generation and carrier injection into the stacked emission units, is highly desirable and advantageous for interface engineering and the performance optimization of tandem OLEDs. In this review, our recent studies on tandem OLEDs are overviewed, especially from interface energetics perspective via photoemission spectroscopy. The electronic structures of various transition metal oxide (TMO)-based CGLs and their role in charge generation process are reviewed, addressing the n-type doping impact of organic layers in CGLs, thermal annealing-induced oxygen vacancy in TMOs, and the interfacial stability of CGLs on the device operational lifetime. The resulting energy level alignments are summarized in correspondence with tandem OLED performance.

Materials science symposium 'heavy ion science in tandem energy region'

Energy Technology Data Exchange (ETDEWEB)

Iwamoto, Akira; Yoshida, Tadashi; Takeuchi, Suehiro [eds.

2000-01-01

The tandem accelerator established at Japan Atomic Energy Research Institute (JAERI) in 1982 has been one of the most prominent electrostatic accelerators in the world. The accelerator has been serving for many researches planned by not only JAERI staff but also researchers of universities and national institutes. After the completion of the tandem booster in 1993, four times higher beam energy became available. These two facilities, the tandem accelerator and the booster, made great strides in heavy ion physics and a lot of achievements have been accumulated until now. The research departments of JAERI were reformed in 1998, and the accelerators section came under the Department of Materials Science. On this reform of the research system, the symposium 'Heavy Ion Science in Tandem Energy Region' was held in cooperation with nuclear and solid state physicists although there has been no such symposium for many years. The symposium was expected to stimulate novel development in both nuclear and solid state physics, and also interdisciplinary physics between nuclear and solid state physics. The 68 papers are indexed individually. (J.P.N.)

Proceedings of the 13th meeting for tandem accelerators and related techniques

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-02-01

The 13th Meeting for Tandem Accelerators and Related Techniques was held on June 8-9, 2000 at Mutsu, Aomori Prefecture, under the auspices of Marine Research Laboratory, Mutsu Establishment, the Japan Atomic Energy Research Institute. About 60 people participated in the meeting from 27 universities and organizations, many of which have a tandem accelerator or an electrostatic accelerator. The objectives of the meeting are to exchange information on tandem accelerates or electrostatic accelerators by making a presentation on related research and topics, and also to enhance mutual friendship of participants, resulting in the contribution to associated R and D. The meeting mainly consisted of presentations by participants and corresponding Q and A; the present situation on facilities of accelerator mass spectrometers (AMS), operations of and research on tandem accelerators or electrostatic accelerators, applications of AMS, related techniques and applications using accelerators, and so on. This report summarizes the contents of presentations made in the meeting. The 30 of the presented papers are indexed individually. (J.P.N.)

Annotating and Interpreting Linear and Cyclic Peptide Tandem Mass Spectra.

Science.gov (United States)

Niedermeyer, Timo Horst Johannes

2016-01-01

Nonribosomal peptides often possess pronounced bioactivity, and thus, they are often interesting hit compounds in natural product-based drug discovery programs. Their mass spectrometric characterization is difficult due to the predominant occurrence of non-proteinogenic monomers and, especially in the case of cyclic peptides, the complex fragmentation patterns observed. This makes nonribosomal peptide tandem mass spectra annotation challenging and time-consuming. To meet this challenge, software tools for this task have been developed. In this chapter, the workflow for using the software mMass for the annotation of experimentally obtained peptide tandem mass spectra is described. mMass is freely available (http://www.mmass.org), open-source, and the most advanced and user-friendly software tool for this purpose. The software enables the analyst to concisely annotate and interpret tandem mass spectra of linear and cyclic peptides. Thus, it is highly useful for accelerating the structure confirmation and elucidation of cyclic as well as linear peptides and depsipeptides.

25 MV tandem accelerator at Oak Ridge

International Nuclear Information System (INIS)

Jones, C.M.

1980-01-01

A new heavy-ion accelerator facility is under construction at the Oak Ridge National Laboratory. A brief description of the scope and status of this project is presented with emphasis on the first operational experience with the 25 MV tandem accelerator

Low driving voltage simplified tandem organic light-emitting devices by using exciplex-forming hosts

Science.gov (United States)

Zhou, Dong-Ying; Cui, Lin-Song; Zhang, Ying-Jie; Liao, Liang-Sheng; Aziz, Hany

2014-10-01

Tandem organic light-emitting devices (OLEDs), i.e., OLEDs containing multiple electroluminescence (EL) units that are vertically stacked, are attracting significant interest because of their ability to realize high current efficiency and long operational lifetime. However, stacking multiple EL units in tandem OLEDs increases driving voltage and complicates fabrication process relative to their standard single unit counterparts. In this paper, we demonstrate low driving voltage tandem OLEDs via utilizing exciplex-forming hosts in the EL units instead of conventional host materials. The use of exciplex-forming hosts reduces the charge injection barriers and the trapping of charges on guest molecules, resulting in the lower driving voltage. The use of exciplex-forming hosts also allows using fewer layers, hence simpler EL configuration which is beneficial for reducing the fabrication complexity of tandem OLEDs.

Tandem queue with server slow-down

NARCIS (Netherlands)

Miretskiy, D.I.; Scheinhardt, W.R.W.; Mandjes, M.R.H.

2007-01-01

We study how rare events happen in the standard two-node tandem Jackson queue and in a generalization, the socalled slow-down network, see [2]. In the latter model the service rate of the first server depends on the number of jobs in the second queue: the first server slows down if the amount of

Optimal dispatching in a tandem queue

NARCIS (Netherlands)

van Leeuwen, D.; Núñez Queija, R.

2017-01-01

We investigate a Markovian tandem queueing model in which service to the first queue is provided in batches. The main goal is to choose the batch sizes so as to minimize a linear cost function of the mean queue lengths. This model can be formulated as a Markov Decision Process (MDP) for which the

Tandem mirror next step conceptual design

International Nuclear Information System (INIS)

Doggett, J.N.; Damm, C.C.; Bulmer, R.H.

1980-01-01

A study was made to define the features of the experimental mirror fusion device - The Tandem Mirror Next Step, or TMNS - that will bridge the gap between present mirror confinement experiments and a power-producing reactor. We outline the project goals, describe some initial device parameters, and relate the technological requirements to ongoing development programs

21 CFR 862.1055 - Newborn screening test system for amino acids, free carnitine, and acylcarnitines using tandem...

Science.gov (United States)

2010-04-01

..., free carnitine, and acylcarnitines using tandem mass spectrometry. 862.1055 Section 862.1055 Food and... screening test system for amino acids, free carnitine, and acylcarnitines using tandem mass spectrometry. (a) Identification. A newborn screening test system for amino acids, free carnitine, and acylcarnitines using tandem...

Radioisotope detection with tandem electrostatic accelerators

Energy Technology Data Exchange (ETDEWEB)

Gove, H E; Elmore, D; Ferraro, R [Rochester Univ., NY (USA). Nuclear Structure Research Lab.; Beukens, R P; Chang, K H; Kilius, L R; Lee, H W; Litherland, A E [Toronto Univ., Ontario (Canada). Dept. of Physics; Purser, K H [General Ionex Corp., Newburyport, MA (USA)

1980-01-01

An MP tandem Van de Graaff accelerator at the University of Rochester has been employed since May 1977 to detect /sup 14/C in terrestrial samples, /sup 36/Cl in terrestrial and extraterrestrial samples and /sup 10/Be and /sup 26/Al in samples produced by reactor and accelerator irradiation. The sample sizes ranged from about 10 to less than 1 mg and the ratio of the radioisotope to the stable isotopes approached one part in 10/sup 16/ for /sup 14/C and /sup 36/Cl and one part in 10/sup 14/ for /sup 10/Be and /sup 26/Al. /sup 14/C has been measured in a number of samples of geological and archaelogical interest. /sup 36/Cl has been measured in various groundwater samples as well as samples at Antarctic meteorites and ice. Dedicated systems for /sup 14/C dating and geological measurements based on the tandem electrostatic accelerator principle are presently under construction for laboratories in the U.S.A., U.K. and Canada.

Progress in the tandem mirror program

International Nuclear Information System (INIS)

Fowler, T.K.; Borchers, R.R.

1981-01-01

Experimental results in TMX have confirmed the basic principles of the tandem-mirror concept. A center-cell particle confinement parameter eta tau approx. 10 11 cm -3 s has been obtained at ion temperatures around 100 eV, which is a hundred-fold improvement over single mirrors at the same temperatures. For TMX these results have been obtained at peak beta values in the center cell in the range 10 to 40%, not yet limited by MHD activity; and ion-cyclotron resonant heating (ICRH) in the Phaedrus tandem-mirror experiment has produced beta values approx. 25%, which is several times the ideal MHD limit for that device. In addition, it has been demonstrated that the end fan chambers of TMX simultaneously isolate the hot electrons from the end walls, provide adequate pumping and conveniently dispose of the exhaust plasma energy either by thermal deposition on the end wall or by direct conversion to electricity (at 48% efficiency in agreement with calculations). Also, evidence was obtained for inherent divertor action in TMX, presumably in part responsible for the observed low impurity level

Tandem planet formation for solar system-like planetary systems

Directory of Open Access Journals (Sweden)

Yusuke Imaeda

2017-03-01

Full Text Available We present a new united theory of planet formation, which includes magneto-rotational instability (MRI and porous aggregation of solid particles in a consistent way. We show that the “tandem planet formation” regime is likely to result in solar system-like planetary systems. In the tandem planet formation regime, planetesimals form at two distinct sites: the outer and inner edges of the MRI suppressed region. The former is likely to be the source of the outer gas giants, and the latter is the source for the inner volatile-free rocky planets. Our study spans disks with a various range of accretion rates, and we find that tandem planet formation can occur for M˙=10−7.3-10−6.9M⊙yr−1. The rocky planets form between 0.4–2 AU, while the icy planets form between 6–30 AU; no planets form in 2–6 AU region for any accretion rate. This is consistent with the gap in the solid component distribution in the solar system, which has only a relatively small Mars and a very small amount of material in the main asteroid belt from 2–6 AU. The tandem regime is consistent with the idea that the Earth was initially formed as a completely volatile-free planet. Water and other volatile elements came later through the accretion of icy material by occasional inward scattering from the outer regions. Reactions between reductive minerals, such as schreibersite (Fe3P, and water are essential to supply energy and nutrients for primitive life on Earth.

Materials Science Division HVEM-Tandem Facility at Argonne National Laboratory

International Nuclear Information System (INIS)

Taylor, A.

1981-10-01

The ANL-Materials Science Division High Voltage Electron Microscope-Tandem Facility is a unique national research facility available to scientists from industry, universities, and other national laboratories, following a peer evaluation of their research proposals by the Facility Steering Committee. The principal equipment consists of a Kratos EM7 1.2-MV high voltage electron microscope, a 300-kV Texas Nuclear ion accelerator, and a National Electrostatics 2-MV Tandem accelerator. Ions from both accelerators are transmitted into the electron microscope through the ion-beam interface. Recent work at the facility is summarized

Construction and operational experience of the Tandem Mirror Experiment-Upgrade (TMX-U)

International Nuclear Information System (INIS)

Chargin, A.K.; Calderon, M.O.; Moore, T.L.

1983-01-01

The Tandem Mirror Experiment-Upgrade (TMX-U) incorporates two new features at Lawrence Livermore National Laboratory (LLNL) tandem mirror program, thermal barriers in the end plugs and injection of the neutral beams at several oblique angles. The thermal barriers isolate the electrons in the end plugs from those in the central cell, making it possible to heat them independently with microwaves. In addition, this innovation produces a large potential gradient in the end plugs with lower magnetic fields and lower neutral-beam energies than would be possible in a conventional tandem mirror device. The TMX-U is also designed to test neutral-beam-injection angles as an experimental parameter. We use angles other than 90 0 to produce a plasma with improved microstability

Artificial urinary sphincter revision for urethral atrophy: comparing single cuff downsizing and tandem cuff placement

Directory of Open Access Journals (Sweden)

Brian J. Linder

Full Text Available ABSTRACT Objective To compare outcomes for single urethral cuff downsizing versus tandem cuff placement during artificial urinary sphincter (AUS revision for urethral atrophy. Materials and Methods We identified 1778 AUS surgeries performed at our institution from 1990-2014. Of these, 406 were first AUS revisions, including 69 revisions for urethral atrophy. Multiple clinical and surgical variables were evaluated for potential association with device outcomes following revision, including surgical revision strategy (downsizing a single urethral cuff versus placing tandem urethral cuffs. Results Of the 69 revision surgeries for urethral atrophy at our institution, 56 (82% were tandem cuff placements, 12 (18% were single cuff downsizings and one was relocation of a single cuff. When comparing tandem cuff placements and single cuff downsizings, the cohorts were similar with regard to age (p=0.98, body-mass index (p=0.95, prior pelvic radiation exposure (p=0.73 and length of follow-up (p=0.12. Notably, there was no difference in 3-year overall device survival compared between single cuff and tandem cuff revisions (60% versus 76%, p=0.94. Likewise, no significant difference was identified for tandem cuff placement (ref. single cuff when evaluating the risk of any tertiary surgery (HR 0.95, 95% CI 0.32-4.12, p=0.94 or urethral erosion/device infection following revision (HR 0.79, 95% CI 0.20-5.22, p=0.77. Conclusions There was no significant difference in overall device survival in patients undergoing single cuff downsizing or tandem cuff placement during AUS revision for urethral atrophy.

Concurrent control system for the JAERI tandem accelerator

International Nuclear Information System (INIS)

Hanashima, Susumu; Shozi, Tokio; Shiozaki, Yasuo; Saito, Motoi; Oogane, Yasuo; Sekiguchi, Satoshi.

1994-01-01

A new control system for the JAERI tandem accelerator is constructed. The system utilizes concurrent processing technology with multiprocessor. Transputers are used both for central processor and I/O front end processors. (author)

NK Cell-Mediated Regulation of Protective Memory Responses against Intracellular Ehrlichial Pathogens.

Directory of Open Access Journals (Sweden)

Samar Habib

Full Text Available Ehrlichiae are gram-negative obligate intracellular bacteria that cause potentially fatal human monocytic ehrlichiosis. We previously showed that natural killer (NK cells play a critical role in host defense against Ehrlichia during primary infection. However, the contribution of NK cells to the memory response against Ehrlichia remains elusive. Primary infection of C57BL/6 mice with Ehrlichia muris provides long-term protection against a second challenge with the highly virulent Ixodes ovatus Ehrlichia (IOE, which ordinarily causes fatal disease in naïve mice. Here, we show that the depletion of NK cells in E. muris-primed mice abrogates the protective memory response against IOE. Approximately, 80% of NK cell-depleted E. muris-primed mice succumbed to lethal IOE infection on days 8-10 after IOE infection, similar to naïve mice infected with the same dose of IOE. The lack of a recall response in NK cell-depleted mice correlated with an increased bacterial burden, extensive liver injury, decreased frequency of Ehrlichia-specific IFN-γ-producing memory CD4+ and CD8+ T-cells, and a low titer of Ehrlichia-specific antibodies. Intraperitoneal infection of mice with E. muris resulted in the production of IL-15, IL-12, and IFN-γ as well as an expansion of activated NKG2D+ NK cells. The adoptive transfer of purified E. muris-primed hepatic and splenic NK cells into Rag2-/-Il2rg-/- recipient mice provided protective immunity against challenge with E. muris. Together, these data suggest that E. muris-induced memory-like NK cells, which contribute to the protective, recall response against Ehrlichia.

Annual report of Tandem Accelerator Center, University of Tsukuba, for fiscal 1976

International Nuclear Information System (INIS)

1977-01-01

A research center of the University of Tsukuba, Tandem Accelerator Center (TAC) has a 12 UD Pelletron tandem accelerator as its principal apparatus; of which acceptance test was finished in July 1976. Activities of the TAC for the period of April 1976 to March 1977 are reported: accelerator and beam transport system, general equipments, equipment development, nuclear physics, chemistry, and biological and medical Science. (Mori, K.)

Annual report of Tandem Accelerator Center, University of Tsukuba, for fiscal 1975

International Nuclear Information System (INIS)

1976-01-01

Tandem Accelerator Center (TAC) is a research center of the University of Tsukuba established mainly for interdisciplinary research. Its principal apparatus is a 12 UD Pelletron tandem accelerator of which assembling was completed in fiscal 1975. Activities of the TAC for the period of April 1975 to March 1976 are reported: accelerator and beam transport system, general equipments, equipment development, and heavy-ion reactions. (Mori, K.)

Polarized ionic source of the tandem accelerator in Kyoto University

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Masanobu; Kuwamoto, Shuichi; Takahashi, Seiji [Kyoto Univ. (Japan). Dept. of Physics] [and others

1997-02-01

A polarized ion source developed under the National Laboratory of High Energy Physics was transferred to the tandem accelerator in Kyoto University at beginning of 1993 to constitute a displacement of incidence into the accelerator. This was an atomic beam type polarized ion source, which is designed to adopt permanent magnets for 6 poles magnet to polarize the electron, to take out atomic nucleus on a shape of positive ion by ECR ionizer after transferring its polarization through transition using radio frequency (RFT), to make it negative ion by charge conversion using alkaline metal vapor, and to put it into the tandem accelerator. Test of the positive ion was finished at the National Laboratory of High Energy Physics, and test in Kyoto University was required after its negative ionization. As the estimated cost was unsufficient and entrance into the ion source facility in the tandem accelerator building was limited in Kyoto University, step of development was slow. Here is reported on present state of the ion source which is now operating stably. (G.K.)

Tandem mirror and field-reversed mirror experiments

Energy Technology Data Exchange (ETDEWEB)

Coensgen, F.H.; Simonen, T.C.; Turner, W.C.

1979-08-21

This paper is largely devoted to tandem mirror and field-reversed mirror experiments at the Lawrence Livermore Laboratory (LLL), and briefly summarizes results of experiments in which field-reversal has been achieved. In the tandem experiment, high-energy, high-density plasmas (nearly identical to 2XIIB plasmas) are located at each end of a solenoid where plasma ions are electrostatically confined by the high positive poentials arising in the end plug plasma. End plug ions are magnetically confined, and electrons are electrostatically confined by the overall positive potential of the system. The field-reversed mirror reactor consists of several small field-reversed mirror plasmas linked together for economic reasons. In the LLL Beta II experiment, generation of a field-reversed plasma ring will be investigated using a high-energy plasma gun with a transverse radial magnetic field. This plasma will be further heated and sustained by injection of intense, high-energy neutral beams.

A review of recent progress in heterogeneous silicon tandem solar cells

Science.gov (United States)

Yamaguchi, Masafumi; Lee, Kan-Hua; Araki, Kenji; Kojima, Nobuaki

2018-04-01

Silicon solar cells are the most established solar cell technology and are expected to dominate the market in the near future. As state-of-the-art silicon solar cells are approaching the Shockley-Queisser limit, stacking silicon solar cells with other photovoltaic materials to form multi-junction devices is an obvious pathway to further raise the efficiency. However, many challenges stand in the way of fully realizing the potential of silicon tandem solar cells because heterogeneously integrating silicon with other materials often degrades their qualities. Recently, above or near 30% silicon tandem solar cell has been demonstrated, showing the promise of achieving high-efficiency and low-cost solar cells via silicon tandem. This paper reviews the recent progress of integrating solar cell with other mainstream solar cell materials. The first part of this review focuses on the integration of silicon with III-V semiconductor solar cells, which is a long-researched topic since the emergence of III-V semiconductors. We will describe the main approaches—heteroepitaxy, wafer bonding and mechanical stacking—as well as other novel approaches. The second part introduces the integration of silicon with polycrystalline thin-film solar cells, mainly perovskites on silicon solar cells because of its rapid progress recently. We will also use an analytical model to compare the material qualities of different types of silicon tandem solar cells and project their practical efficiency limits.

Hybrid tandem solar cells with depleted-heterojunction quantum dot and polymer bulk heterojunction subcells

KAUST Repository

Kim, Taesoo

2015-10-01

We investigate hybrid tandem solar cells that rely on the combination of solution-processed depleted-heterojunction colloidal quantum dot (CQD) and bulk heterojunction polymer:fullerene subcells. The hybrid tandem solar cell is monolithically integrated and electrically connected in series with a suitable p-n recombination layer that includes metal oxides and a conjugated polyelectrolyte. We discuss the monolithic integration of the subcells, taking into account solvent interactions with underlayers and associated constraints on the tandem architecture, and show that an adequate device configuration consists of a low bandgap CQD bottom cell and a high bandgap polymer:fullerene top cell. Once we optimize the recombination layer and individual subcells, the hybrid tandem device reaches a VOC of 1.3V, approaching the sum of the individual subcell voltages. An impressive fill factor of 70% is achieved, further confirming that the subcells are efficiently connected via an appropriate recombination layer. © 2015.

Magnet system for a thermal barrier Tandem Mirror Reactor

International Nuclear Information System (INIS)

Kim, N.S.; Conn, R.W.

1981-01-01

The magnet system for a thermal barrier D-D tandem mirror reactor has been studied as part of the UCLA tandem mirror reactor design study SATYR. Three main considerations in designing the SATYR magnet system are to obtain the desired field strength variation throughout the system, to have proper space for plasma and neutron shielding, and to satisfy the MHD stability to achieve maximum central cell /beta/. Due to the importance and the complexity, the 'internal' field reversal magnet is the main concern in the entire magnet system for SATYR. Two different magnet designs, a non-uniform current density solenoid and a higher-order solenoid, are discussed. Coil levitation for the internal field reversal magnet has been analyzed

Preliminary design of a Tandem-Mirror-Next-Step facility

International Nuclear Information System (INIS)

Damm, C.C.; Doggett, J.N.; Bulmer, R.H.

1980-01-01

The Tandem-Mirror-Next-Step (TMNS) facility is designed to demonstrate the engineering feasibility of a tandem-mirror reactor. The facility is based on a deuterium-tritium (D-T) burning, tandem-mirror device with a fusion power output of 245 MW. The fusion power density in the central cell is 2.1 MW/m 3 , with a resultant neutron wall loading of 0.5 MW/m 2 . Overall machine length is 116 m, and the effective central-cell length is 50.9 m. The magnet system includes end cells with yin-yang magnets to provide magnetohydrodynamic (MHD) stability and thermal-barrier cells to help achieve a plasma Q of 4.7 (where Q = fusion power/injected power). Neutral beams at energies up to 200 keV are used for plasma heating, fueling, and barrier pumping. Electron cyclotron resonant heating at 50 and 100 GHz is used to control the electron temperature in the barriers. Based on the resulting engineering design, the overall cost of the facility is estimated to be just under $1 billion. Unresolved physics issues include central-cell β-limits against MHD ballooning modes (the assumed reference value of β exceeds the current theory-derived limit), and the removal of thermalized α-particles from the plasma

High throughput pyrosequencing technology for molecular differential detection of Babesia vogeli, Hepatozoon canis, Ehrlichia canis and Anaplasma platys in canine blood samples.

Science.gov (United States)

Kaewkong, Worasak; Intapan, Pewpan M; Sanpool, Oranuch; Janwan, Penchom; Thanchomnang, Tongjit; Kongklieng, Amornmas; Tantrawatpan, Chairat; Boonmars, Thidarut; Lulitanond, Viraphong; Taweethavonsawat, Piyanan; Chungpivat, Sudchit; Maleewong, Wanchai

2014-06-01

Canine babesiosis, hepatozoonosis, ehrlichiosis, and anaplasmosis are tick-borne diseases caused by different hemopathogens. These diseases are causes of morbidity and mortality in dogs. The classic method for parasite detection and differentiation is based on microscopic observation of blood smears. The limitations of the microscopic method are that its performance requires a specially qualified person with professional competence, and it is ineffective in differentiating closely related species. This study applied PCR amplification with high throughput pyrosequencing for molecular differential detection of the following 4 hemoparasites common to tropical areas in dog blood samples: Babesia vogeli, Hepatozoon canis, Ehrlichia canis, and Anaplasma platys. PCR was initially used to amplify specific target regions of the ribosomal RNA genes of each parasite using 2 primer pairs that included 18S rRNA for protozoa (B. vogeli and H. canis) and 16S rRNA for rickettsia (E. canis and A. platys). Babesia vogeli and H. canis were discriminated using 9 nucleotide positions out of 30 base pairs, whereas E. canis and A. platys were differentiated using 15 nucleotide positions out of 34 base pairs that were determined from regions adjacent to 3' ends of the sequencing primers. This method provides a challenging alternative for a rapid diagnosis and surveillance of these tick-borne diseases in canines. Copyright © 2014 Elsevier GmbH. All rights reserved.

SU-F-T-30: Comprehensive Dosimetric Characterization of the Novel Direction Modulation Brachytherapy (DMBT) Tandem Applicator Using Monte Carlo Simulations

Energy Technology Data Exchange (ETDEWEB)

Safigholi, H; Mashouf, S; Soliman, Abraam; Owrangi, A; Song, W Y [Deprtment of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON (Canada); Han, D [Deprtment of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON (Canada); Department of Radiation Oncology, University of California San Francisco, San Francisco, CA (United States)

2016-06-15

Purpose: To characterize the dosimetric properties/distributions of the novel proposed direction modulated brachytherapy (DMBT) tandem applicator in combination with 192Ir HDR source, and compare against conventional tandem design, using Monte Carlo simulations. Methods: The proposed DMBT tandem applicator is designed for image-guided adaptive brachytherapy, especially MRI, of cervical cancer. It has 6 peripheral holes of 1.3-mm width, grooved along a 5.4-mm diameter nonmagnetic tungsten alloy rod of density 18.0 g/cc, capable of generating directional dose profiles – leading to enhanced dose sculpting capacity through inverse planning. In-water dosimetric parameters for the DMBT and conventional tandems have been calculated for various radial distances away and around the tandems. For the DMBT tandem, the cumulative dose from the 192Ir source occupying 1) one and 2) all six holes in equal dwell times was calculated and normalized to match the dose rate of the open source (in conventional tandem) at 1 cm from the center. This is done to compare and contrast the characteristic dose distributions to that of the isotropic TG43-based 192Ir source. Results: All dose rates were normalized at 1-cm radius from the center of the applicators, containing source(s). The normalized dose rates at 0.5, 3.0, and 5.0-cm radiuses were then 388, 11.3, and 4.1% for conventional tandem, 657, 8.1, and 2.7% for DMBT tandem with the source in one hole at front entrance, and 436, 10.9, and 3.8% for DMBT tandem with the source in all six holes. For the DMBT tandem case with the source in one hole, the backside transmissions were 47, 2.4, and 0.9%, respectively. Conclusion: The DMBT tandem is able to generate closely similar dosimetric characteristics as that of the single-channel conventional tandem if needed (with the source occupying all six holes), at the same time, generate directional radiation profile(s) for favorably enabling 3D dose sculpting capability.

Zinc tin oxide as high-temperature stable recombination layer for mesoscopic perovskite/silicon monolithic tandem solar cells

KAUST Repository

Werner, Jérémie

2016-12-05

Perovskite/crystalline silicon tandem solar cells have the potential to reach efficiencies beyond those of silicon single-junction record devices. However, the high-temperature process of 500 °C needed for state-of-the-art mesoscopic perovskite cells has, so far, been limiting their implementation in monolithic tandem devices. Here, we demonstrate the applicability of zinc tin oxide as a recombination layer and show its electrical and optical stability at temperatures up to 500 °C. To prove the concept, we fabricate monolithic tandem cells with mesoscopic top cell with up to 16% efficiency. We then investigate the effect of zinc tin oxide layer thickness variation, showing a strong influence on the optical interference pattern within the tandem device. Finally, we discuss the perspective of mesoscopic perovskite cells for high-efficiency monolithic tandem solar cells. © 2016 Author(s)

Tandem Wittig-ene reaction approach to kainic acid

Digital Repository Service at National Institute of Oceanography (India)

Majik, M.S.; Parameswaran, P.S.; Tilve, S.G.

The first example of a tandem Wittig-intramolecular ene reaction approach and its application toward the synthesis of kainic acid is reported. The synthetic pathway involves conversion of prenyl bromide into phosphorane 3, followed by one-pot Wittig...

Improve definition of titanium tandems in MR-guided high dose rate brachytherapy for cervical cancer using proton density weighted MRI

International Nuclear Information System (INIS)

Hu, Yanle; Esthappan, Jacqueline; Mutic, Sasa; Richardson, Susan; Gay, Hiram A; Schwarz, Julie K; Grigsby, Perry W

2013-01-01

For cervical cancer patients treated with MR-guided high dose rate brachytherapy, the accuracy of radiation delivery depends on accurate localization of both tumors and the applicator, e.g. tandem and ovoid. Standard T2-weighted (T2W) MRI has good tumor-tissue contrast. However, it suffers from poor uterus-tandem contrast, which makes the tandem delineation very challenging. In this study, we evaluated the possibility of using proton density weighted (PDW) MRI to improve the definition of titanium tandems. Both T2W and PDW MRI images were obtained from each cervical cancer patient. Imaging parameters were kept the same between the T2W and PDW sequences for each patient except the echo time (90 ms for T2W and 5.5 ms for PDW) and the slice thickness (0.5 cm for T2W and 0.25 cm for PDW). Uterus-tandem contrast was calculated by the equation C = (S u -S t )/S u , where S u and S t represented the average signal in the uterus and the tandem, respectively. The diameter of the tandem was measured 1.5 cm away from the tip of the tandem. The tandem was segmented by the histogram thresholding technique. PDW MRI could significantly improve the uterus-tandem contrast compared to T2W MRI (0.42±0.24 for T2W MRI, 0.77±0.14 for PDW MRI, p=0.0002). The average difference between the measured and physical diameters of the tandem was reduced from 0.20±0.15 cm by using T2W MRI to 0.10±0.11 cm by using PDW MRI (p=0.0003). The tandem segmented from the PDW image looked more uniform and complete compared to that from the T2W image. Compared to the standard T2W MRI, PDW MRI has better uterus-tandem contrast. The information provided by PDW MRI is complementary to those provided by T2W MRI. Therefore, we recommend adding PDW MRI to the simulation protocol to assist tandem delineation process for cervical cancer patients

Accelerator tube vacuum conditions in the NSF tandem

International Nuclear Information System (INIS)

Groome, A.E.

1979-08-01

The Nuclear Structure Facility currently under construction at the Daresbury Laboratory contains a 30 MV tandem Van de Graaff accelerator with a modular design of accelerator tube. The vacuum system requirements are specified to limit beam loss due to charge-state-changing collisions in the residual gas. This report gives an assessment of some of the parameters affecting the vacuum pressure in an operational machine. Measurements are made of the vacuum conductance and outgassing rate of accelerator tube modules. An assessment is made of the effects of temperature rise, beam mis-steering and the presence of suppression magnets on the ultimate vacuum obtainable. Predictions are made of the pressure profile throughout the machine and consideration is given to operational problems such as tube conditioning and temporary loss of pumping. A schematic diagram of the tandem and its vacuum system is shown. (author)

A tandem queue with delayed server release

NARCIS (Netherlands)

Nawijn, W.M.

1997-01-01

We consider a tandem queue with two stations. The rst station is an s-server queue with Poisson arrivals and exponential service times. After terminating his service in the rst station, a customer enters the second station to require service at an exponential single server, while in the meantime he

The "Bologna-München" Tandem--Experiencing Interculturality

Science.gov (United States)

De Martino, Sandro

2016-01-01

This case study describes the "Bologna-München" Tandem, a cross-border collaboration which began in 2011. The aim of the collaboration is to give students studying Italian at the Ludwig- Maximilians-University in Munich and students studying German at the University of Bologna the opportunity to experience interculturality through…

Band gap engineering of tandem structured CIGS compound absorption layer fabricated by sputtering and selenization

International Nuclear Information System (INIS)

Kang, San; Sharma, Rahul; Sim, Jae-Kwan; Lee, Cheul-Ro

2013-01-01

Highlights: ► Systematic band gap engineering to fabricate tandem Cu(In,Ga)Se 2 absorption layers. ► XRD shows prominent (1 1 2) reflection shift for attributed CIS, CIGS, and CGS phases. ► Optical transmittance and reflectance spectrum are improved towards infrared region. ► The Cu/In + Ga and Ga/In + Ga effect is matched with highest efficient solar cell. ► Tandem CIS/CIGS/CGS layer, the band gap is increased from 1.15 to 2.06 eV. -- Abstract: Band gap engineering was executed to fabricate a multi-junction stacked i.e. tandem Cu(In,Ga)Se 2 (CIGS) absorption layer. The CIGS absorption layers consist of multi-junction stacked CIS/CIGS/CGS thin films from bottom to top with increasing band gap. Tandem CIGS layers were fabricated by using three precursor of CuIn, In/CuGa/In, and CuGa onto the Mo coated soda-lime glass (SLG) by the sequential sputtering of CuIn, CuGa, and In targets. The CIG precursors were converted into CIGS absorption thin film by selenization process. From the X-ray diffraction (XRD) pattern of CIS/CIGS/CGS tandem layer, with the prominent peak shift for (1 1 2) reflections was attributed to the individual CIS, CIGS, and CGS phases at 26.76°, 27.15°, and 27.65° diffraction angles, respectively. The morphologies and atomic (at%) composition uniformity onto the surface and along the depth were extensively analyzed with field effect scanning electron microscope (FESEM) attached energy dispersive spectroscopy (EDS) and secondary ion mass spectroscopy (SIMS). The optical properties such as transmittance, reflectance and absorbance were found to improve in the infrared region for all the tandem CIGS layers. Near the fundamental absorption edge, the absorption coefficient was approached to 10 5 cm −1 for CIS/CIGS/CGS tandem layer. The straight-line behavior indicates that the films have a direct band gap. The band gap was found to increase from 1.15 to 1.74 eV with the Ga-grading along the depth of individual CIS, CIGS, and CGS thin films

Green oxidations: Titanium dioxide induced tandem oxidation coupling reactions

OpenAIRE

Jeena, Vineet; Robinson, Ross S

2009-01-01

Summary The application of titanium dioxide as an oxidant in tandem oxidation type processes is described. Under microwave irradiation, quinoxalines have been synthesized in good yields from the corresponding ?-hydroxyketones.

Generating hydrogen from sunlight and water using photovoltaic tandem cell

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-15

Photoelectrochemical conversion of solar energy to energy in hydrogen at viable efficiency is a long-term goal needed to usher in the hydrogen economy worldwide. The twin cell technology based Tandem Cell tackles a number of challenges faced by single photoelectrochemical cell based water splitting and offers a novel way of utilising complimentary parts of the solar spectrum in two cells. The overall process results in a complete system driven by solar energy that splits water into hydrogen and oxygen. Hydrogen Solar Ltd is a UK based enterprise that is working towards commercialisation of this Tandem Cell technology. One of the main project activities involved the development and optimisation of methods for preparation of larger scale photocatalytic electrodes using reproducible low cost industrial processes, with efficiencies equal to or greater than those from small scale samples made experimentally in University laboratories. Stability is also an important issue and endurance testing was performed on some samples. Spray pyrolysis methods offer considerable promise as for preparation of metal oxide semiconductor films at low cost, reproducibly. These studies lead to optimised designs for Tandem Cells, resulting in construction of an array of 12 Tandem Cells. The findings of this array work, in particular engineering issues, were very significant. Based on this work it is intended to build another two array systems that consists of 24 Tandem Cells which will be tested for light to chemical conversion efficiency, to determine what efficiency has been achieved overall. The main conclusions resulting from this project were as follows. Overall, considerable progress was made in characterising the factors that affect photoelectrode performance efficiency but that, losses in efficiency when increasing the area of photoelectrodes was greater than expected and optimisation of efficiency at practical device scale needs more work. Based on the outcome of this work program

Design and fabrication of a high performance inorganic tandem solar cell with 11.5% conversion efficiency

International Nuclear Information System (INIS)

Amiri, Omid; Mir, Noshin; Ansari, Fatemeh; Salavati-Niasari, Masoud

2017-01-01

Tandem solar cell is a design that combines two types of solar cells to benefit their advantages. We show a new concept for achieving highly efficient dye sensitized and quantum dot tandem solar cells. The new tandem cell further enhances the performance of the device, leading to a power conversion efficiency more than 11% under 1.5 Air Mass. To the best of our knowledge, this is the first time that the efficiency over 11 percent is achieved based on tandem solar cell. X-ray diffraction, Transmission Electron Microscopy, Scanning Electron Microscopy, Current-Voltage measurments, Intensity modulated photocurrent spectroscopy, intensity modulated photovoltage spectroscopy, Energy Dispersive X-ray spectroscopy, Brunauer-Emmett-Teller, Barrett-Joyner-Halenda and absorption spectroscopy were used to characterize the fabricated solar cells.

A serological and molecular survey of Babesia vogeli, Ehrlichia canis and Rickettsia spp. among dogs in the state of Maranhão, northeastern Brazil

Directory of Open Access Journals (Sweden)

Andréa Pereira da Costa

Full Text Available This study evaluated exposure and infection by tick-borne agents (Babesia vogeli, Ehrlichia canis and Rickettsia spp. in 172 dogs in rural areas and 150 dogs in urban areas of the municipality of Chapadinha, state of Maranhão, northeastern Brazil, using molecular and serological methods. Overall, 16.1% of the sampled dogs (52/322 were seroreactive to B. vogeli, with endpoint titers ranging from 40 to 640. For E. canis, 14.6% of the dogs (47/322 were seroreactive, with endpoint titers from 80 to 163,840. Antibodies reactive to at least one of the five species of Rickettsia were detected in 18.9% of the dogs (61/322, with endpoint titers ranging from 64 to 4,096. High endpoint titers were observed for Rickettsia amblyommii. Three (0.9% and nine (2.8% canine blood samples were PCR-positive for Babesia spp. and E. canis. The ticks collected from urban dogs were all Rhipicephalus sanguineus sensu lato, whereas the rural dogs were infested by R. sanguineus s.l, Amblyomma cajennense sensu lato and Amblyomma ovale. One A. ovale tick was found to be infected by Rickettsia bellii. This study provides an epidemiological background for controlling and preventing canine tick-borne diseases in a neglected region of Brazil.

Use of molecular ion beams from a tandem accelerator

International Nuclear Information System (INIS)

Faibis, A.; Goldring, G.; Hass, M.; Kaim, R.; Plesser, I.; Vager, Z.

1981-01-01

A large variety of positive molecular ion beams can be produced by gaseous charge exchange in the terminal of a tandem accelerator. After acceleration the molecules are usually dissociated by passage through a thin foil. Measurements of the break-up products provide a way to study both the structure of incident ions and the effects of electronic potentials on the internuclear interaction inside the foil. Beam intensities of a few picoamperes are quite adequate for these measurements, and the relatively high energy obtained by use of a tandem accelerator has the advantage of minimizing multiple scattering effects in the foil. The main difficulty in using the molecular beams lies in the large magnetic rigidity of singly-charged heavy molecular ions

Seroprevalence of Ehrlichia ruminantium antibodies and its associated risk factors in indigenous goats of South Africa.

Science.gov (United States)

Mdladla, Khanyisile; Dzomba, Edgar F; Muchadeyi, Farai C

2016-03-01

The present study investigated the seroprevalence of antibodies to Ehrlichia ruminantium and the associated risk factors in goats from five different farming provinces of South Africa. Sera collected from 686 goats of the commercial meat type (n=179), mohair type (n=9), non-descript indigenous goats from Eastern Cape (n=56), KwaZulu-Natal (n=209), Limpopo (n=111), North West (n=61) and Northern Cape (n=11) provinces and a feral Tankwa goat (n=50) were tested for the presence of immunoglobulin G (IgG) antibodies to antigens of E. ruminantium using the indirect fluorescent-antibody test (IFAT). Fifty two percent of these goats had ticks. The overall seroprevalence of antibodies to E. ruminantium was 64.87% (445/686) with the highest seroprevalence reported for Limpopo (95.50%) and lowest for Northern Cape (20.29%). Highest seroprevalence for antibodies to E. ruminantium was observed in goats from endemic regions (76.09%), and from smallholder production systems (89.54%). High seroprevalence was also observed in non-descript indigenous goats (85.04%), adult goat (69.62%), in does (67.46%) and goats infested with ticks (85.79%). The logistic model showed a gradient of increasing risk for commercial meat type Savanna (OR=3.681; CI=1.335-10.149) and non-descript indigenous (OR=3.466; CI=1.57-7.645) compared to Boer goats and for goats from the smallholder production system (OR=2.582; CI=1.182-5.639) and those with ticks (OR=3.587; CI=2.105-6.112). Results from this study showed that E. ruminantium infections were prevalent but were widely and unevenly distributed throughout South Africa. Findings from the study facilitate identification and mapping of risk areas for heartwater and its endeminicity in South Africa and should be taken into consideration for future disease control strategies and local goat improvement programs. Copyright © 2016 Elsevier B.V. All rights reserved.

Improved voltage performance of the Oak Ridge 25URC tandem accelerator

International Nuclear Information System (INIS)

Meigs, M.J.; Jones, C.M.; Haynes, D.L.; Juras, R.C.; Ziegler, N.F.; Roatz, J.E.; Rathmell, R.D.

1989-01-01

This paper reports on the Oak Ridge 25URC tandem electrostatic accelerator one of two accelerators operated by the Holifield Heavy Ion Research Facility (HHIRF) at the Oak Ridge National Laboratory. Placed into routine service in 1982, the accelerator has provided a wide range of heavy ion beams for research in nuclear and atomic physics. These beams have been provided both directly and after further acceleration by the Oak Ridge Isochronous Cyclotron (ORIC). Show schematically in this paper, the tandem accelerator is a model 25URC Pelletron accelerator

Displacement of particles in microfluidics by laser-generated tandem bubbles

Science.gov (United States)

Lautz, Jaclyn; Sankin, Georgy; Yuan, Fang; Zhong, Pei

2010-11-01

The dynamic interaction between laser-generated tandem bubble and individual polystyrene particles of 2 and 10 μm in diameter is studied in a microfluidic channel (25 μm height) by high-speed imaging and particle image velocimetry. The asymmetric collapse of the tandem bubble produces a pair of microjets and associated long-lasting vortices that can propel a single particle to a maximum velocity of 1.4 m/s in 30 μs after the bubble collapse with a resultant directional displacement up to 60 μm in 150 μs. This method may be useful for high-throughput cell sorting in microfluidic devices.

Designing and overproducing a tandem epitope of gp350/220 that shows a potential to become an EBV vaccine

Directory of Open Access Journals (Sweden)

Widodo

2018-03-01

Full Text Available Background: Epstein-Barr virus (EBV can cause cancer in people from around the world. There is no EBV vaccine available for use on a global scale. However, emerging evidence suggests that the epitope on the gp350/220 capsid protein may be developed into an EBV vaccine. Nevertheless, the production of small, single epitope is challenging of stability issues and possible alteration of peptide structure. In this study, a tandem epitope was developed consisting of three single epitopes, aimed to improve stability, antigenicity and preserve epitope structure. Materials and methods: A tandem epitope was designed using bioinformatics based on the epitope structure of the gp350/220 protein. The tandem epitope structure was analyzed using a protein folding method with Abalone software, which was further refined via YASARA force field and molecular repairing using a FoldX method. Immunogenicity was examined with Epitopia software, whereas allergen properties were tested using AlgPred. The pattern of the tandem epitope binding with anti-gp350/220 antibodies was performed using Z-dock and snugDock. The tandem epitope was then overproduced in E. coli strain BL21 as a host cell. Result: Our model demonstrated a successfully designed and overproduced tandem epitope. The tandem epitope demonstrated a similar structure compared with the epitope of whole protein gp350/220. Our epitope also demonstrated non-allergen and antigenicity properties, and possessed antibody binding patterns consistent with whole protein gp350/220. Conclusion and recommendation: These data suggest a novel tandem epitope composed of three similar epitopes demonstrates antigenicity, structure, and binding properties consistent with whole protein gp350/220. We also demonstrate successful production of the tandem epitope using E. coli strain BL21 as a host. Future in vivo experimental animal research is necessary to test the ability of this tandem epitope to stimulate antibody production

Present status of tandem accelerator analysis facility in National Institute for Environmental Studies

Energy Technology Data Exchange (ETDEWEB)

Kume, Hiroshi; Shibata, Yasuyuki; Tanaka, Atsushi; Yoneda, Minoru; Kumamoto, Yuichiro; Uehiro, Takashi; Morita, Masatoshi [National Inst. for Environmental Studies, Tsukuba, Ibaraki (Japan)

1996-12-01

In National Institute for Environmental Studies, two types of tandem accelerator analysis facilities were able to be installed in September, 1995. One is the accelerator mass analysis exclusive equipment with a 5 MV tandem accelerator, and the other is the high energy ion beam analyzer, in which the surface analysis system is connected to a 1 MV tandem accelerator, mainly used for PIXE measurement. The accelerator mass analyzer can be roughly divided into four parts, that is, ion source and negative ion injection system, accelerator, high energy analysis system, minute amount isotope beam line and control system. These parts are briefly explained. The test measurement of carbon isotope ratio was carried out, but the results dispersed and unsatisfactory. As for the ion beam analyzer, the surface analysis system (RBS400) of Charles Evans and Associates is combined with a 1 MV PELETRON tandem accelerator (3SDH) of NEC, and these are described. This analyzer also is not in the state that the steady operation can be carried out. Slight leak occurred in the ion source. The countermeasures to both cases are in progress. (K.I.)

The nuclear structure facility tandem at Daresbury laboratory

International Nuclear Information System (INIS)

Voss, R.G.P.

1976-01-01

A 30MV tandem electrostatic accelerator for ions of all types, including heavy ions, is being built at Daresbury Laboratory. Construction is well advanced, and considerable effort is continuing to be devoted to R and D programme into the technology of electrostatic accelerators

Concurrent control system for the JAERI tandem accelerator

International Nuclear Information System (INIS)

Hanashima, S.; Shoji, T.; Horie, K.; Tsukihashi, Y.

1992-01-01

Concurrent processing with a multiprocessor system is introduced to the particle accelerator control system region. The control system is a good application in both logical and physical aspects. A renewal plan of the control system for the JAERI tandem accelerator is discussed. (author)

Monolithic Perovskite Silicon Tandem Solar Cells with Advanced Optics

Energy Technology Data Exchange (ETDEWEB)

Goldschmidt, Jan C.; Bett, Alexander J.; Bivour, Martin; Blasi, Benedikt; Eisenlohr, Johannes; Kohlstadt, Markus; Lee, Seunghun; Mastroianni, Simone; Mundt, Laura; Mundus, Markus; Ndione, Paul; Reichel, Christian; Schubert, Martin; Schulze, Patricia S.; Tucher, Nico; Veit, Clemens; Veurman, Welmoed; Wienands, Karl; Winkler, Kristina; Wurfel, Uli; Glunz, Stefan W.; Hermle, Martin

2016-11-14

For high efficiency monolithic perovskite silicon tandem solar cells, we develop low-temperature processes for the perovskite top cell, rear-side light trapping, optimized perovskite growth, transparent contacts and adapted characterization methods.

A new modified tandem appliance for management of developing Class III malocclusion

OpenAIRE

Sukh, Ram; Singh, Gyan P; Tandon, Pradeep

2013-01-01

Most developing Class III patients display a retruded maxilla. Early intervention in mixed dentition is associated with better patient compliance and possibly a better orthopedic response, which can produce favorable results. The aim of this article is to present the fabrication of the new modified tandem appliance and its use in management of developing Class III malocclusion. The therapeutic results of a new modified tandem appliance are presented in an 8 year-old male patient with anterior...

Tandem mirror next step: remote maintenance

International Nuclear Information System (INIS)

Doggett, J.N.; Damm, C.C.; Hanson, C.L.

1980-01-01

This study of the next proposed experiment in the Mirror Fusion Program, the Tandem Mirror Next Step (TMNS), has included serious consideration of the maintenance requirements of such a large source of high energy neutrons with its attendant throughput of tritium. Although maintenance will be costly in time and money, our conclusion is that with careful attention to a design for maintenance plan such a device can be reliably operated

The First Tandem, All-exciplex-based WOLED

Science.gov (United States)

Hung, Wen-Yi; Fang, Guan-Cheng; Lin, Shih-Wei; Cheng, Shuo-Hsien; Wong, Ken-Tsung; Kuo, Ting-Yi; Chou, Pi-Tai

2014-06-01

Exploiting our recently developed bilayer interface methodology, together with a new wide energy-gap, low LUMO acceptor (A) and the designated donor (D) layers, we succeeded in fabricating an exciplex-based organic light-emitting diode (OLED) systematically tuned from blue to red. Further optimization rendered a record-high blue exciplex OLED with ηext of 8%. We then constructed a device structure configured by two parallel blend layers of mCP/PO-T2T and DTAF/PO-T2T, generating blue and yellow exciplex emission, respectively. The resulting device demonstrates for the first time a tandem, all-exciplex-based white-light OLED (WOLED) with excellent efficiencies ηext: 11.6%, ηc: 27.7 cd A-1, and ηp: 15.8 ml W-1 with CIE(0.29, 0.35) and CRI 70.6 that are nearly independent of EL intensity. The tandem architecture and blend-layer D/A (1:1) configuration are two key elements that fully utilize the exciplex delay fluorescence, providing a paragon for the use of low-cost, abundant organic compounds en route to commercial WOLEDs.

Tandem collimators for the JET tangential gamma-ray spectrometer

International Nuclear Information System (INIS)

Soare, Sorin; Balshaw, Nick; Blanchard, Patrick; Craciunescu, Teddy; Croft, David; Curuia, Marian; Edlington, Trevor; Kiptily, Vasily; Murari, Andrea; Prior, Phil; Sanders, Steven; Syme, Brian; Zoita, Vasile

2011-01-01

The tangential gamma-ray spectrometer (TGRS) of the JET tokamak fusion facility is an important diagnostics for investigating the fast particle evolution. A well defined field of view for the TGRS diagnostics is essential for its proper operation and this is to be determined by a rather complex system of collimators and shields both for the neutron and gamma radiations. A conceptual design for this system has been carried out with the main design target set to maximize the signal-to-background ratio at the spectrometer detector, the ratio being defined in terms of the plasma emitted gamma radiation and the gamma-ray background. As a first phase of the TGRS diagnostics upgrade a set of two tandem collimators has been designed with the aim of determining a quasi-tangential field of view through JET tokamak plasmas. A modular design of the tandem system has been developed in order to allow for the construction of different configurations for deuterium and deuterium-tritium discharges. The internal structure of the collimators consists of nuclear grade lead and high density polyethylene slabs arranged in an optimized pattern. The performance of a simplified geometry of the tandem collimator configuration has been evaluated by neutron and photon transport calculations and the numerical results show that the design parameters can be attained.

Hybrid Tandem Quantum Dot/Organic Solar Cells with Enhanced Photocurrent and Efficiency via Ink and Interlayer Engineering

KAUST Repository

Kim, Taesoo

2018-05-03

Realization of colloidal quantum dot (CQD)/organic photovoltaic (OPV) tandem solar cells that integrate the strong infrared absorption of CQDs with large photovoltages of OPVs is an attractive option toward high-performing, low-cost thin film solar cells. To date, monolithic hybrid tandem integration of CQD/OPV solar cells has been restricted due to the CQD ink’s catastrophic damage to the organic subcell, thus forcing the low bandgap CQD to be used as front cell. This sub-optimal configuration limits the maximum achievable photocurrent in CQD/OPV hybrid tandem solar cells. In this work, we demonstrate hybrid tandem solar cells employing a low-bandgap CQD back cell on top of an organic front cell thanks to a modified CQD ink formulation and a robust interconnection layer (ICL) which together overcome the long-standing integration challenges for CQD and organic subcells. The resulting tandem architecture surpasses previously reported current densities by ~20-25% and yields a state-of-the-art power conversion efficiency (PCE) of 9.4%.

In-terminal ECR Ion Source of the Tandem Accelerator at JAERI

CERN Document Server

Matsuda, M; Takeuchi, S

1999-01-01

Electron Cyclotron Resonance Ion Source(ECRIS)s are able to produce intense beams of highly charged positive ions and used injection system for cyclotron, linac as well as experiments of atomic physics. The tandem accelerator system has been benefiting from use of an electron stripper at the high voltage terminal. The most probable charged state after a foil stripper is, however, much lower than the highest charge state of ions with an intensity of more than several emA from a high performance ECRIS. With respect to beam current, the life time of stripper foils decrease with increasing beam current. Especially for very heavy ions, it is difficult to obtain a stable and intense beam for a long time without foil exchange. Use of an ECRIS in a tandem accelerator is expected to increase beam intensity, beam energy and beam species. A small permanent magnet ECRIS has been installed in the high voltage terminal of the vertical and folded type 20UR Pelletron tandem accelerator at Japan Atomic Energy Research Institu...

Tandem mass spectrometry data quality assessment by self-convolution

Directory of Open Access Journals (Sweden)

Tham Wai

2007-09-01

Full Text Available Abstract Background Many algorithms have been developed for deciphering the tandem mass spectrometry (MS data sets. They can be essentially clustered into two classes. The first performs searches on theoretical mass spectrum database, while the second based itself on de novo sequencing from raw mass spectrometry data. It was noted that the quality of mass spectra affects significantly the protein identification processes in both instances. This prompted the authors to explore ways to measure the quality of MS data sets before subjecting them to the protein identification algorithms, thus allowing for more meaningful searches and increased confidence level of proteins identified. Results The proposed method measures the qualities of MS data sets based on the symmetric property of b- and y-ion peaks present in a MS spectrum. Self-convolution on MS data and its time-reversal copy was employed. Due to the symmetric nature of b-ions and y-ions peaks, the self-convolution result of a good spectrum would produce a highest mid point intensity peak. To reduce processing time, self-convolution was achieved using Fast Fourier Transform and its inverse transform, followed by the removal of the "DC" (Direct Current component and the normalisation of the data set. The quality score was defined as the ratio of the intensity at the mid point to the remaining peaks of the convolution result. The method was validated using both theoretical mass spectra, with various permutations, and several real MS data sets. The results were encouraging, revealing a high percentage of positive prediction rates for spectra with good quality scores. Conclusion We have demonstrated in this work a method for determining the quality of tandem MS data set. By pre-determining the quality of tandem MS data before subjecting them to protein identification algorithms, spurious protein predictions due to poor tandem MS data are avoided, giving scientists greater confidence in the

Tandem mass spectrometry data quality assessment by self-convolution.

Science.gov (United States)

Choo, Keng Wah; Tham, Wai Mun

2007-09-20

Many algorithms have been developed for deciphering the tandem mass spectrometry (MS) data sets. They can be essentially clustered into two classes. The first performs searches on theoretical mass spectrum database, while the second based itself on de novo sequencing from raw mass spectrometry data. It was noted that the quality of mass spectra affects significantly the protein identification processes in both instances. This prompted the authors to explore ways to measure the quality of MS data sets before subjecting them to the protein identification algorithms, thus allowing for more meaningful searches and increased confidence level of proteins identified. The proposed method measures the qualities of MS data sets based on the symmetric property of b- and y-ion peaks present in a MS spectrum. Self-convolution on MS data and its time-reversal copy was employed. Due to the symmetric nature of b-ions and y-ions peaks, the self-convolution result of a good spectrum would produce a highest mid point intensity peak. To reduce processing time, self-convolution was achieved using Fast Fourier Transform and its inverse transform, followed by the removal of the "DC" (Direct Current) component and the normalisation of the data set. The quality score was defined as the ratio of the intensity at the mid point to the remaining peaks of the convolution result. The method was validated using both theoretical mass spectra, with various permutations, and several real MS data sets. The results were encouraging, revealing a high percentage of positive prediction rates for spectra with good quality scores. We have demonstrated in this work a method for determining the quality of tandem MS data set. By pre-determining the quality of tandem MS data before subjecting them to protein identification algorithms, spurious protein predictions due to poor tandem MS data are avoided, giving scientists greater confidence in the predicted results. We conclude that the algorithm performs well

Band gap engineering of tandem structured CIGS compound absorption layer fabricated by sputtering and selenization

Energy Technology Data Exchange (ETDEWEB)

Kang, San; Sharma, Rahul; Sim, Jae-Kwan [Semiconductor Materials Processing Laboratory, School of Advanced Materials Engineering, College of Engineering, Research Center for Advanced Materials Development (RCAMD), Chonbuk National University, Deokjin-dong 664-14, Jeonju 561-756 (Korea, Republic of); Lee, Cheul-Ro, E-mail: crlee7@jbnu.ac.kr [Semiconductor Materials Processing Laboratory, School of Advanced Materials Engineering, College of Engineering, Research Center for Advanced Materials Development (RCAMD), Chonbuk National University, Deokjin-dong 664-14, Jeonju 561-756 (Korea, Republic of)

2013-06-25

Highlights: ► Systematic band gap engineering to fabricate tandem Cu(In,Ga)Se{sub 2} absorption layers. ► XRD shows prominent (1 1 2) reflection shift for attributed CIS, CIGS, and CGS phases. ► Optical transmittance and reflectance spectrum are improved towards infrared region. ► The Cu/In + Ga and Ga/In + Ga effect is matched with highest efficient solar cell. ► Tandem CIS/CIGS/CGS layer, the band gap is increased from 1.15 to 2.06 eV. -- Abstract: Band gap engineering was executed to fabricate a multi-junction stacked i.e. tandem Cu(In,Ga)Se{sub 2} (CIGS) absorption layer. The CIGS absorption layers consist of multi-junction stacked CIS/CIGS/CGS thin films from bottom to top with increasing band gap. Tandem CIGS layers were fabricated by using three precursor of CuIn, In/CuGa/In, and CuGa onto the Mo coated soda-lime glass (SLG) by the sequential sputtering of CuIn, CuGa, and In targets. The CIG precursors were converted into CIGS absorption thin film by selenization process. From the X-ray diffraction (XRD) pattern of CIS/CIGS/CGS tandem layer, with the prominent peak shift for (1 1 2) reflections was attributed to the individual CIS, CIGS, and CGS phases at 26.76°, 27.15°, and 27.65° diffraction angles, respectively. The morphologies and atomic (at%) composition uniformity onto the surface and along the depth were extensively analyzed with field effect scanning electron microscope (FESEM) attached energy dispersive spectroscopy (EDS) and secondary ion mass spectroscopy (SIMS). The optical properties such as transmittance, reflectance and absorbance were found to improve in the infrared region for all the tandem CIGS layers. Near the fundamental absorption edge, the absorption coefficient was approached to 10{sup 5} cm{sup −1} for CIS/CIGS/CGS tandem layer. The straight-line behavior indicates that the films have a direct band gap. The band gap was found to increase from 1.15 to 1.74 eV with the Ga-grading along the depth of individual CIS, CIGS

Highly efficient tandem organic light-emitting devices employing an easily fabricated charge generation unit

Science.gov (United States)

Yang, Huishan; Yu, Yaoyao; Wu, Lishuang; Qu, Biao; Lin, Wenyan; Yu, Ye; Wu, Zhijun; Xie, Wenfa

2018-02-01

We have realized highly efficient tandem organic light-emitting devices (OLEDs) employing an easily fabricated charge generation unit (CGU) combining 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile with ultrathin bilayers of CsN3 and Al. The charge generation and separation processes of the CGU have been demonstrated by studying the differences in the current density-voltage characteristics of external-carrier-excluding devices. At high luminances of 1000 and 10000 cd/m2, the current efficiencies of the phosphorescent tandem device are about 2.2- and 2.3-fold those of the corresponding single-unit device, respectively. Simultaneously, an efficient tandem white OLED exhibiting high color stability and warm white emission has also been fabricated.

Serology, molecular detection and risk factors of Ehrlichia canis infection in dogs in Costa Rica.

Science.gov (United States)

Barrantes-González, Alexander V; Jiménez-Rocha, Ana E; Romero-Zuñiga, Juan José; Dolz, Gaby

2016-10-01

A cross-sectional study combining different serological and molecular techniques for the detection of Ehrlichia species in dogs and their ticks was carried out with data from all regions of Costa Rica. A seroprevalence of 32.1% (131/408), and infection with E. canis of 3.2% (13/407) was found, whereas 6.9% (9/130) of ticks attached to the dogs were PCR positive to E. canis. Higher prevalences were found outside the Greater Metropolitan Area (GMA). Risk factors associated with E. canis seropositivity were age, between 2 and 7 years (RR: 1.6, 95% CI: 1.2-2.2) and 8-15 years (RR: 1.8, 95% CI: 1.2-3.0), number of dogs/total of households [Dogs per Household Ratio (DHR) ≥3.1 (RR: 2.0; 95% CI: 1.4-3.0)], number of dogs infested with at least one tick/total of dogs sampled [Tick Infestation Prevalence (TIP)≥31% (RR: 2.1; 95% CI:1.3-3.3)] and living outside the GMA (RR: 1.7; 95% CI: 1.2-2.4) and being a mixed-breed dog (RR: 1.5; 95% CI: 1.1-2.1). Risk factors for E. canis PCR positive dogs were a depressive attitude (OR: 11.2; 95% CI: 1.1-115.9), fever (OR:4.8; 95% CI:1.2-19.3), DHR≥3.1 (OR: 5.7; 95% CI:1.7-19.2)], number of ticks/total of dogs sampled [Tick Distribution Ratio (TDR) ≥2.1 (OR: 6.5; 95% CI: 1.3-31.8)], and TIP≥40% (OR: 5.7; 95% CI: 1.7-19.2). This paper describes E. canis seroprevalence, PCR prevalence and tick analysis in dogs from Costa Rica, with associated clinical signs and owner perceptions. In summary, most of the E. canis infections in dogs in our country seemed to pass unnoticed by owners. Since most of the seropositive dogs (97.7%, 131/134) were negative for E. canis DNA in their blood, it is important to determine in future studies if these dogs recovered from the E. canis infection without any medication, or are persistently infected, and will develop chronic disease. Copyright © 2016 Elsevier GmbH. All rights reserved.

Graphene based integrated tandem supercapacitors fabricated directly on separators

KAUST Repository

Chen, Wei

2015-04-09

It is of great importance to fabricate integrated supercapacitors with extended operation voltages as high energy density storage devices. In this work, we develop a novel direct electrode deposition on separator (DEDS) process to fabricate graphene based integrated tandem supercapacitors for the first time. The DEDS process generates compact graphene-polyaniline electrodes directly on the separators to form integrated supercapacitors. The integrated graphene-polyaniline tandem supercapacitors demonstrate ultrahigh volumetric energy density of 52.5 Wh L^(−1) at power density of 6037 W L^(−1) and excellent gravimetric energy density of 26.1 Wh kg^(−1) at power density of 3002 W kg^(−1) with outstanding electrochemical stability for over 10000 cycles. This study show great promises for the future development of integrated energy storage devices.

Development of High Efficiency Four-Terminal Perovskite-Silicon Tandems

Science.gov (United States)

Duong, The Duc

This thesis is concerned with the development of high efficiency four-terminal perovskite-silicon tandem solar cells with the potential to reduce the cost of solar energy. The work focuses on perovskite top cells and can be divided into three main parts: developing low parasitic absorption and efficient semi-transparent perovskite cells, doping perovskite materials with rubidium, and optimizing perovskite material's bandgap with quadruple-cation and mixed-halide. A further section investigates the light stability of optimized bandgap perovskite cells. In a four-terminal mechanically stacked tandem, the perovskite top cell requires two transparent contacts at both the front and rear sides. Through detailed optical and electrical power loss analysis of the tandem efficiency due to non-ideal properties of the two transparent contacts, optimal contact parameters in term of sheet resistance and transparency are identified. Indium doped tin oxide by sputtering is used for both two transparent contacts and their deposition parameters are optimized separately. The semi-transparent perovskite cell using MAPbI3 has an efficiency of more than 12% with less than 12% parasitic absorption and up to 80% transparency in the long wavelength region. Using a textured foil as anti-reflection coating, an outstanding average transparency of 84% in the long wavelength is obtained. The low parasitic absorption allows an opaque version of the semi-transparent perovskite cell to operate efficiently in a filterless spectrum splitting perovskite-silicon tandem configuration. To further enhance the performance of perovskite cells, it is essential to improve the quality of perovskite films. This can be achieved with mixed-perovskite FAPbI3/MAPbBr3. However, mixed-perovskite films normally contain small a small amount of a non-perovskite phase, which is detrimental for the cell performance. Rb-doping is found to eliminate the formation of the non-perovskite phase and enhance the crystallinity of

Tandem mirror technology demonstration facility

Energy Technology Data Exchange (ETDEWEB)

1983-10-01

This report describes a facility for generating engineering data on the nuclear technologies needed to build an engineering test reactor (ETR). The facility, based on a tandem mirror operating in the Kelley mode, could be used to produce a high neutron flux (1.4 MW/M/sup 2/) on an 8-m/sup 2/ test area for testing fusion blankets. Runs of more than 100 h, with an average availability of 30%, would produce a fluence of 5 mW/yr/m/sup 2/ and give the necessary experience for successful operation of an ETR.

Tandem mirror technology demonstration facility

International Nuclear Information System (INIS)

1983-10-01

This report describes a facility for generating engineering data on the nuclear technologies needed to build an engineering test reactor (ETR). The facility, based on a tandem mirror operating in the Kelley mode, could be used to produce a high neutron flux (1.4 MW/M 2 ) on an 8-m 2 test area for testing fusion blankets. Runs of more than 100 h, with an average availability of 30%, would produce a fluence of 5 mW/yr/m 2 and give the necessary experience for successful operation of an ETR

Finding all sorting tandem duplication random loss operations

DEFF Research Database (Denmark)

Bernt, Matthias; Chen, Kuan Yu; Chen, Ming Chiang

2011-01-01

A tandem duplication random loss (TDRL) operation duplicates a contiguous segment of genes, followed by the random loss of one copy of each of the duplicated genes. Although the importance of this operation is founded by several recent biological studies, it has been investigated only rarely from...

Y-Chromosome short tandem repeat, typing technology, locus ...

African Journals Online (AJOL)

Aghomotsegin

2015-07-08

Jul 8, 2015 ... Y-Chromosome short tandem repeat, typing technology, locus information and allele frequency in different population: A review. Muhanned Abdulhasan Kareem1, Ameera Omran Hussein2 and Imad Hadi Hameed2*. 1Babylon University, Centre of Environmental Research, Hilla City, Iraq. 2Department of ...

X-Chromosome short tandem repeat, advantages and typing ...

African Journals Online (AJOL)

Microsatellites of the X-chromosome have been increasingly studied in recent years as a useful tool in forensic analysis. This review describes some details of X-chromosomal short tandem repeat (STR) analysis. Among them are: microsatellites, amplification using polymerase chain reaction (PCR) of STRs, PCR product ...

A Tandem-electrostatic-quadrupole for accelerator-based BNCT

International Nuclear Information System (INIS)

Kreiner, A.J.; Kwan, J.W.; Burlon, A.A.; Di Paolo, H.; Henestroza, E.; Minsky, D.M.; Valda, A.A.; Debray, M.E.; Somacal, H.

2007-01-01

A project to develop a Tandem-electrostatic-quadrupole (TESQ) accelerator for accelerator-based boron neutron capture therapy (AB-BNCT) is described. A folded Tandem, with 1.25 MV terminal voltage, combined with an electrostatic quadrupole (ESQ) chain is being proposed. The project goal is a machine capable of delivering 30 mA of 2.5 MeV protons to be used in conjunction with a neutron production target based on the 7 Li(p, n) 7 Be reaction slightly beyond its resonance at 2.25 MeV. This machine is conceptually shown to be capable of accelerating a 30 mA proton beam to 2.5 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the 7 Li(p, n) 7 Be reaction, to perform BNCT treatment for deep-seated tumors in less than an hour. This electrostatic machine is the technologically simplest and cheapest solution for optimized AB-BNCT

MINIMARS: An attractive small tandem mirror fusion reactor

International Nuclear Information System (INIS)

Perkins, L.J.; Logan, B.G.; Doggett, J.N.; Devoto, R.S.

1986-01-01

Through the innovative design of a novel end plug scheme employing octopole MHD stabilization, the authors present the conceptual design of ''MINIMARS'', a small commercial fusion reactor based on the tandem mirror principle. The current baseline for MINIMARS has a net electric output of 600 MWe and they have configured the design for short construction times, factory-built modules, inherently safe blanket systems, and multiplexing in station sizes of ≅ 600-2400 MWe. They demonstrate that the compact octopole end cell provides a number of advantages over the more conventional quadrupole (yin-yang) end cell encountered in the MARS tandem mirror reactor study, and enables ignition to be achieved with much shorter central cell lengths. Accordingly, being economic in small sizes, MINIMARS provides an attractive alternative to the more conventional larger conceptual fusion reactors encountered to date, and would contribute significantly to the lowering of utility financial risk in a developing fusion economy

Evolution of the Fusion Power Demonstration tandem mirror reactor configuration

International Nuclear Information System (INIS)

O'Toole, J.A.; Lousteau, D.C.

1985-01-01

This paper gives a presentation of the evolution of configurations proposed for tandem mirror Fusion Power Demonstration (FPD) machines. The FPD study was undertaken to scope the mission as well as the technical and design requirements of the next tandem mirror device. Three configurations, entitled FPD I, II, and III were studied. During this process new systems were conceived and integrated into the design, resulting in a significantly changed overall machine configuration. The machine can be divided into two areas. A new center cell configuration, minimizing magnetic field ripple and thus maximizing center cell fusion power, features a semicontinuous solenoid. A new end cell has evolved which maintains the required thermal barrier in a significantly reduced axial length. The reduced end cell effective length leads to a shorter central cell length being required to obtain minimum ignition conditions. Introduced is the concept of an electron mantle stabilized octopole arrangement. The engineering features of the new end cell and maintenance concepts developed are influenced to a great extent by the octopole-based design. The new ideas introduced during the FPD study have brought forth a new perspective of the size, design, and maintenance of tandem mirror reactors, making them more attractive as commercial power sources

Single-graded CIGS with narrow bandgap for tandem solar cells.

Science.gov (United States)

Feurer, Thomas; Bissig, Benjamin; Weiss, Thomas P; Carron, Romain; Avancini, Enrico; Löckinger, Johannes; Buecheler, Stephan; Tiwari, Ayodhya N

2018-01-01

Multi-junction solar cells show the highest photovoltaic energy conversion efficiencies, but the current technologies based on wafers and epitaxial growth of multiple layers are very costly. Therefore, there is a high interest in realizing multi-junction tandem devices based on cost-effective thin film technologies. While the efficiency of such devices has been limited so far because of the rather low efficiency of semitransparent wide bandgap top cells, the recent rise of wide bandgap perovskite solar cells has inspired the development of new thin film tandem solar devices. In order to realize monolithic, and therefore current-matched thin film tandem solar cells, a bottom cell with narrow bandgap (~1 eV) and high efficiency is necessary. In this work, we present Cu(In,Ga)Se 2 with a bandgap of 1.00 eV and a maximum power conversion efficiency of 16.1%. This is achieved by implementing a gallium grading towards the back contact into a CuInSe 2 base material. We show that this modification significantly improves the open circuit voltage but does not reduce the spectral response range of these devices. Therefore, efficient cells with narrow bandgap absorbers are obtained, yielding the high current density necessary for thin film multi-junction solar cells.

Advanced astigmatism-corrected tandem Wadsworth mounting for small-scale spectral broadband imaging spectrometer.

Science.gov (United States)

Lei, Yu; Lin, Guan-yu

2013-01-01

Tandem gratings of double-dispersion mount make it possible to design an imaging spectrometer for the weak light observation with high spatial resolution, high spectral resolution, and high optical transmission efficiency. The traditional tandem Wadsworth mounting is originally designed to match the coaxial telescope and large-scale imaging spectrometer. When it is used to connect the off-axis telescope such as off-axis parabolic mirror, it presents lower imaging quality than to connect the coaxial telescope. It may also introduce interference among the detector and the optical elements as it is applied to the short focal length and small-scale spectrometer in a close volume by satellite. An advanced tandem Wadsworth mounting has been investigated to deal with the situation. The Wadsworth astigmatism-corrected mounting condition for which is expressed as the distance between the second concave grating and the imaging plane is calculated. Then the optimum arrangement for the first plane grating and the second concave grating, which make the anterior Wadsworth condition fulfilling each wavelength, is analyzed by the geometric and first order differential calculation. These two arrangements comprise the advanced Wadsworth mounting condition. The spectral resolution has also been calculated by these conditions. An example designed by the optimum theory proves that the advanced tandem Wadsworth mounting performs excellently in spectral broadband.

Enhancement of efficiencies for tandem green phosphorescent organic light-emitting devices with a p-type charge generation layer

Energy Technology Data Exchange (ETDEWEB)

Yoo, Byung Soo; Jeon, Young Pyo; Lee, Dae Uk; Kim, Tae Whan, E-mail: twk@hanayng.ac.kr

2014-10-15

The operating voltage of the tandem green phosphorescent organic light-emitting device with a 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile layer was improved by 3% over that of the organic light-emitting device with a molybdenum trioxide layer. The maximum brightness of the tandem green phosphorescent organic light-emitting device at 21.9 V was 26,540 cd/m{sup 2}. The dominant peak of the electroluminescence spectra for the devices was related to the fac-tris(2-phenylpyridine) iridium emission. - Highlights: • Tandem OLEDs with CGL were fabricated to enhance their efficiency. • The operating voltage of the tandem OLED with a HAT-CN layer was improved by 3%. • The efficiency and brightness of the tandem OLED were 13.9 cd/A and 26,540 cd/m{sup 2}. • Efficiency of the OLED with a HAT-CN layer was lower than that with a MoO{sub 3} layer. - Abstract: Tandem green phosphorescent organic light-emitting devices with a 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile or a molybdenum trioxide charge generation layer were fabricated to enhance their efficiency. Current density–voltage curves showed that the operating voltage of the tandem green phosphorescent organic light-emitting device with a 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile layer was improved by 3% over that of the corresponding organic light-emitting device with a molybdenum trioxide layer. The efficiency and the brightness of the tandem green phosphorescent organic light-emitting device were 13.9 cd/A and 26,540 cd/m{sup 2}, respectively. The current efficiency of the tandem green phosphorescent organic light-emitting device with a 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile layer was lower by 1.1 times compared to that of the corresponding organic light-emitting device with molybdenum trioxide layer due to the decreased charge generation and transport in the 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile layer resulting from triplet–triplet exciton annihilation.

Preparation of ethylene/1-hexene copolymers from ethylene using a fully silica-supported tandem catalyst system

NARCIS (Netherlands)

Karbach, Fabian F.; Macko, Tibor; Duchateau, Robbert

2016-01-01

A silica-supported tandem catalyst system, capable of producing ethylene/1-hexene copolymers from ethylene being the single monomer, has been investigated. As tandem couple a phenoxyimine titanium catalyst for ethylene trimerization was combined with a metallocene catalyst for α-olefin

SU-D-BRF-05: A Novel System to Provide Real-Time Image-Guidance for Intrauterine Tandem Insertion and Placement

Energy Technology Data Exchange (ETDEWEB)

Price, M; Fontenot, J [pF Biomedical Solutions LLC, Baton Rouge, LA (United States)

2014-06-01

Purpose: To develop a system that provides real-time image-guidance for intrauterine tandem insertion and placement for brachytherapy. Methods: The conceptualized system consists of an intrauterine tandem with a transparent, lensed tip, a flexible miniature fiber optic scope, light source and interface for CCD coupling. The tandem tip was designed to act as a lens providing a wide field-of-view (FOV) with minimal image distortion and focus length appropriate for the application. The system is designed so that once inserted, the image-guidance component of the system can be removed and brachytherapy can be administered without interfering with source transport or disturbing tandem placement. Proof-of-principle studies were conducted to assess the conceptualized system's (1) lens functionality (clarity, focus and FOV) (2) and ability to visualize the cervical os of a female placed in the lithotomy position. Results: A prototype of this device was constructed using a commercial tandem modified to incorporate a transparent tip that internally coupled with a 1.9mm diameter fiber optic cable. The 900mm-long cable terminated at an interface that provided illumination as well as facilitated visualization of patient anatomy on a computer. The system provided a 23mm FOV with a focal length of 1cm and provided clear visualization of the cervix, cervical fornix and cervical os. The optical components of the system are easily removed without perturbing the position of a tandem placed in a common fixation clamp. Conclusion: Clinicians frequently encounter difficulty inserting an intrauterine tandem through the cervical os, circumventing fibrotic tissue or masses within the uterus, and positioning the tandem without perforating the uterus. To mitigate these challenges, we have designed and conducted proof-of- principle studies to discern the utility of a prototype device that provides real-time image-guidance for intrauterine tandem placement using fiber optic components.

Citrate Anticoagulation in Tandem Membrane Plasma-Exchange or Immunoadsorption and Hemodialysis in Patients With Immunological Diseases and Dialysis-Dependence.

Science.gov (United States)

Ponikvar, Rafael; Gubenšek, Jakob; Ponikvar, Jadranka Buturović

2016-06-01

In 1996 we performed tandem membrane plasma exchange-hemodialysis in a 3-year-old girl and tandem immunoadsorption-hemodialysis with citrate as the only anticoagulant in a patient with Goodpasture's syndrome. In the present study, we evaluated the feasibility, efficacy and safety of 24 tandem plasma exchange/immunoadsorption hemodialysis procedures in four different circuit setups with citrate as the only anticoagulant. In two setups, the tandem procedures were connected in series (plasma exchange hemodialysis and immunoadsorption hemodialysis), while in the other two setups they were in parallel (plasma exchange hemodialysis with independent blood circuits and plasma exchange hemodialysis with independent arterial blood lines, but with a common return line). All tandem procedures were feasible, efficient and safe. No serious side-effects were recorded. The most elegant setup was the procedure with independent, parallel blood circuits. However, serial tandem procedures provided for the elimination of citrate and normalization of electrolytes before blood was returned to the patient. © 2016 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.

Improved Tandem Measurement Techniques for Aerosol Particle Analysis

Science.gov (United States)

Rawat, Vivek Kumar

Non-spherical, chemically inhomogeneous (complex) nanoparticles are encountered in a number of natural and engineered environments, including combustion systems (which produces highly non-spherical aggregates), reactors used in gas-phase materials synthesis of doped or multicomponent materials, and in ambient air. These nanoparticles are often highly diverse in size, composition and shape, and hence require determination of property distribution functions for accurate characterization. This thesis focuses on development of tandem mobility-mass measurement techniques coupled with appropriate data inversion routines to facilitate measurement of two dimensional size-mass distribution functions while correcting for the non-idealities of the instruments. Chapter 1 provides the detailed background and motivation for the studies performed in this thesis. In chapter 2, the development of an inversion routine is described which is employed to determine two dimensional size-mass distribution functions from Differential Mobility Analyzer-Aerosol Particle Mass analyzer tandem measurements. Chapter 3 demonstrates the application of the two dimensional distribution function to compute cumulative mass distribution function and also evaluates the validity of this technique by comparing the calculated total mass concentrations to measured values for a variety of aerosols. In Chapter 4, this tandem measurement technique with the inversion routine is employed to analyze colloidal suspensions. Chapter 5 focuses on application of a transverse modulation ion mobility spectrometer coupled with a mass spectrometer to study the effect of vapor dopants on the mobility shifts of sub 2 nm peptide ion clusters. These mobility shifts are then compared to models based on vapor uptake theories. Finally, in Chapter 6, a conclusion of all the studies performed in this thesis is provided and future avenues of research are discussed.

Designs of tandem-mirror fusion reactors

International Nuclear Information System (INIS)

Carlson, G.A.; Barr, W.L.; Boghosian, B.M.

1981-01-01

We have completed a comparative evaluation of several end plug configurations for tandem mirror fusion reactors with thermal barriers. The axi-cell configuration has been selected for further study and will be the basis for a detailed conceptual design study to be carried out over the next two years. The axi-cell end plug has a simple mirror cell produced by two circular coils followed by a transition coil and a yin-yang pair, which provides for MHD stability

SU-E-T-661: Quantitative MRI Assessment of a Novel Direction-Modulated Brachytherapy Tandem Applicator for Cervical Cancer

Energy Technology Data Exchange (ETDEWEB)

Soliman, A; Elzibak, A; Fatemi, A; Safigholi, H; Leung, E; Ravi, A; Song, W [Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada); Han, D [Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada); University of California, San Diego, La Jolla, CA (United States)

2015-06-15

Purpose: To quantitatively evaluate the MR image quality of a novel direction modulated brachytherapy (DMBT) tandem applicator for cervical cancer, using the clinical MRI scanning protocol for image guided brachytherapy. Methods: The tungsten alloy-based applicator was placed in a water phantom and clinical imaging protocol was performed. Axial images were acquired using 2D turbo-spin echo (TSE) T2-weighted sequence on a 1.5T GE 450w MR scanner and an 8-channel body coil. As multi-channel receiver coil was used, inhomogeneities in the B1 receive field must be considered before performing the quantification process. Therefore the applicator was removed from the phantom and the whole imaging session was performed again for the water phantom with the same parameters. Images from the two scans were then subtracted, resulting in a difference image that only shows the applicator with its surrounding magnetic susceptibility dipole artifact. Line profiles were drawn and plotted on the difference image at various angles and locations along the tandem. Full width at half maximum (FWHM) was measured at all the line profiles to quantify the extent of the artifact. Additionally, the extent of the artifact along the diameter of the tandem was measured at various angles and locations. Results: After removing the background inhomogeneities of the receiver coil, FWHM of the tandem measured 5.75 ± 0.35 mm (the physical tandem diameter is 5.4 mm). The average extent of the artifacts along the diameter of the tandem measured is 2.14 ± 0.56 mm. In contrast to CT imaging of the same applicator (not shown here), the tandem can be easily identified without additional correction algorithms. Conclusion: This work demonstrated that the novel DMBT tandem applicator has minimal susceptibility artifact in T2-weighted images employed in clinical practice for MRI-guided brachytherapy of cervical cancer.

Catalytic stereoselective synthesis of highly substituted indanones via tandem Nazarov cyclization and electrophilic fluorination trapping.

Science.gov (United States)

Nie, Jing; Zhu, Hong-Wei; Cui, Han-Feng; Hua, Ming-Qing; Ma, Jun-An

2007-08-02

A new catalytic stereoselective tandem transformation via Nazarov cyclization/electrophilic fluorination has been accomplished. This sequence is efficiently catalyzed by a Cu(II) complex to afford fluorine-containing 1-indanone derivatives with two new stereocenters with high diastereoselectivity (trans/cis up to 49/1). Three examples of catalytic enantioselective tandem transformation are presented.

Authentication of Fish Products by Large-Scale Comparison of Tandem Mass Spectra

DEFF Research Database (Denmark)

Wulff, Tune; Nielsen, Michael Engelbrecht; Deelder, André M.

2013-01-01

Authentication of food is a major concern worldwide to ensure that food products are correctly labeled in terms of which animals are actually processed for consumption. Normally authentication is based on species recognition by comparison of selected sequences of DNA or protein. We here present...... a new robust, proteome-wide tandem mass spectrometry method for species recognition and food product authentication. The method does not use or require any genome sequences or selection of tandem mass spectra but uses all acquired data. The experimental steps were performed in a simple, standardized...

Near-optimal switching strategies for a tandem queue

NARCIS (Netherlands)

van Leeuwen, D.; Núñez-Queija, R.; Boucherie, R.J.; van Dijk, N.M.

2017-01-01

Motivated by various applications in logistics, road traffic and production management, we investigate two versions of a tandem queueing model in which the service rate of the first queue can be controlled. The objective is to keep the mean number of jobs in the second queue as low as possible,

Near-optimal switching strategies for a tandem queue

NARCIS (Netherlands)

D. van Leeuwen (Daphne); R. Núñez Queija (Rudesindo)

2017-01-01

textabstractMotivated by various applications in logistics, road traffic and production management, we investigate two versions of a tandem queueing model in which the service rate of the first queue can be controlled. The objective is to keep the mean number of jobs in the second queue as low as

Molecular detection of Anaplasma platys, Anaplasma phagocytophilum and Wolbachia sp. but not Ehrlichia canis in Croatian dogs.

Science.gov (United States)

Huber, Doroteja; Reil, Irena; Duvnjak, Sanja; Jurković, Daria; Lukačević, Damir; Pilat, Miroslav; Beck, Ana; Mihaljević, Željko; Vojta, Lea; Polkinghorne, Adam; Beck, Relja

2017-11-01

The bacteria Anaplasma platys, Anaplasma phagocytophilum and Ehrlichia canis are tick-borne agents that cause canine vector-borne disease. The prevalence of these pathogens in South Eastern Europe is unknown with the exception of an isolated case of A. platys detected in a dog imported into Germany from Croatia. To gain a better insight into their presence and prevalence, PCR-based screening for these bacterial pathogens was performed on domesticated dogs from different regions of Croatia. Blood samples from 1080 apparently healthy dogs from coastal and continental parts of Croatia as well as tissue samples collected from 63 deceased dogs with a history of anaemia and thrombocytopenia were collected for molecular screening by an Anaplasmataceae-specific 16S rRNA conventional PCR. Positive samples were confirmed using a second Anaplasmataceae-specific PCR assay with the PCR product sequenced for the purpose of bacterial species identification. All sequenced isolates were georeferenced and a kernel intensity estimator was used to identify clusters of greater case intensity. 42/1080 (3.8%; CI 2.7-5.0) of the healthy dogs were PCR positive for bacteria in the Anaplasmataceae. Sequencing of the 16S rRNA gene amplified from these positive samples revealed the presence of A. platys in 2.5% (CI 1.6-3.4%, 27 dogs), A. phagocytophilum in 0.3% (CI 0-0.6%, 3 dogs) and a Wolbachia endosymbiont in 1.1% (CI 0.4-1.6%, 12 dogs) of dogs screened in this study. Necropsied dogs were free from infection. Notably, no evidence of E. canis infection was found in any animal. This survey represents a rare molecular study of Anaplasmataceae in dogs in South Eastern Europe, confirming the presence of A. platys and A. phagocytophilum but not E. canis. The absence of E. canis was surprising given it has been described in all other Mediterranean countries surveyed and raises questions over the regional vector capacity of the Rhipicephalus sanguineus tick.

Prevalence of Ehrlichia canis, Anaplasma platys, Babesia canis vogeli, Hepatozoon canis, Bartonella vinsonii berkhoffii, and Rickettsia spp. in dogs from Grenada.

Science.gov (United States)

Yabsley, Michael J; McKibben, John; Macpherson, Calum N; Cattan, Peggy F; Cherry, Natalie A; Hegarty, Barbara C; Breitschwerdt, Edward B; O'Connor, Tom; Chandrashekar, Ramaswamy; Paterson, Tara; Perea, Marta Lanza; Ball, Geoffrey; Friesen, Stanley; Goedde, Jill; Henderson, Brooke; Sylvester, Wayne

2008-02-14

To identify the tick-borne pathogens in dogs from Grenada, we conducted a serologic survey for Ehrlichia canis in 2004 (104 dogs) and a comprehensive serologic and molecular survey for a variety of tick-borne pathogens in 2006 (73 dogs). In 2004 and 2006, 44 and 32 dogs (42.3% and 43.8%) were seropositive for E. canis, respectively. In 2006, several tick-borne pathogens were identified by serology and PCR. DNA of E. canis, Anaplasma platys, Babesia canis vogeli, Hepatozoon canis, and Bartonella sp. were identified in 18 (24.7%), 14 (19.2%), 5 (7%), 5 (7%), and 1 (1.4%) dogs, respectively. Six (8.2%) dogs were seropositive for Bartonella vinsonii subsp. berkhoffii. All dogs were seronegative and PCR-negative for Rickettsia spp. Coinfection with two or three pathogens was observed in eight dogs. Partial 16S rRNA E. canis and A. platys sequences were identical to sequences in GenBank. Partial 18S rRNA gene sequences from the Grenadian H. canis were identical to each other and had one possible mismatch (ambiguous base) from H. canis detected from Spain and Brazil. Grenadian B. c. vogeli sequences were identical to B. c. vogeli from Brazil and Japan. All of the detected pathogens are transmitted, or suspected to be transmitted, by Rhipicephalus sanguineus. Results of this study indicate that dogs from Grenada are infected with multiple tick-borne pathogens; therefore, tick-borne diseases should be included as differentials for dogs exhibiting thrombocytopenia, leukopenia, fever, or lethargy. One pathogen, E. canis, is also of potential public health significance.

Status of JAERI tandem accelerator

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Tadashi; Kanda, Susumu; Takeuchi, Suehiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] (and others)

2001-02-01

JAERI Tandem Accelerator had been operated approximately 230 days in fiscal year of 1999. Meanwhile, we had three times of maintenance period with vent. Total operation-times were 5273 hours. We could not carry out the experiment using rare gas, due to malfunction of the RF power supply for the ECR ion source. The type of the RF power supply is peculiar and it is impossible to get spare parts for repair. We are now investigating the backup RF power supply. The power supply for the magnet became unstable due to degradation of insulation in the shunt resistance, which is used for feedback stabilization. Stability was recovered after cleaning. The acrylic resin shaft was cracked. This cracks have a potential for severe accidents. So far bearing of the shaft has no problem. The reason of cracks may be self-destruction by charge accumulation in the shaft. JAERI Tandem Accelerator is approximately 20 years old. There appear requirements on the higher ion currents for additional ion species. Therefore, authors are investigating cost effective improvement plans of RFQ (Radio Frequency Quadra-pole) and IH type accelerator based on KEK (High Energy Accelerator Research Organization) R and D. As a whole, maintenance services for the control system are increasing due to some changes of computer programs. There are some difficulties to keep skilled personnel for facilities operation. Authors are gradually increasing hired personnel with contract from 1993. However, loads for JAERI permanent staffs are still heavy. It takes much longer time to educate skilled persons especially for safety. (Y. Tanaka)

Characteristics of KUMM Tandem Electrostatic Accelerator 5SDH-2

International Nuclear Information System (INIS)

Kitamura, Akira; Furuyama, Yuichi; Taniike, Akira; Kubota, Naoyoshi

1998-01-01

The KUMM Tandem Electrostatic Accelerator was heavily damaged by the Hanshin Earthquake in Jan. 1995, and the renewed version 5SDH-2 was installed in 1996. The fundamental characteristics of the renewed system is reported together with the system composition. (author)

Robust Tension Control of Strip for 5-Stand Tandem Cold Mills

Directory of Open Access Journals (Sweden)

Behrooz Shafiei

2014-01-01

Full Text Available Tandem cold rolling process is a nonlinear complex system with external and internal uncertainties and significant disturbances. The improvement in the quality of the final output depends on the control strategy of centerline thickness and interstand tension. This paper focuses on interstand tension control problem in 5-stand tandem cold rolling mills. Tension dynamics can be described by a nominal model perturbed by parametric uncertainties. In order to overcome the model uncertainties and external disturbances, suboptimal H∞ and μ controllers are proposed and the Hankel-norm approximation is used to reduce the order of μ controller. The performance of the proposed controllers is demonstrated by some simulations.

Transport of dc and bunched beams through a 25 MV folded tandem accelerator

International Nuclear Information System (INIS)

Milner, W.T.; Alton, G.D.; Hensley, D.C.; Jones, C.M.; King, R.F.; Larson, J.D.; Moak, C.D.; Sayer, R.O.

1975-01-01

Studies of beam transport through the planned ORNL 25 MV folded tandem accelerator demonstrate efficient utilization of phase-space acceptance and the feasibility of injecting bunched beams from the tandem accelerator into the Oak Ridge Isochronous Cyclotron (ORIC). Use of a 180 0 bending magnet in the terminal provides outstanding charge state selection and permits better control of the high-energy beam transport than has previously been possible in conventional tandem accelerators. Time spreads introduced in bunched beams by the 180 0 magnet are kept within a 6 0 RF acceptance window at ORIC provided the beam has a crossover in the center of the 180 0 magnet. Ion masses from 12 to 240 amu, preinjection energies from 150 to 500 keV and terminal voltages from 7.5 to 25 MV were studied for dc beams and beams bunched by various modulation techniques. (U.S.)

TMX-U [Tandem Mirror Experiment-Upgrade]: Final report, Volume 1

International Nuclear Information System (INIS)

Porter, G.D.

1988-01-01

This paper discusses the plasma control and the physics accomplishments of the Tandem Mirror Experiment-Upgrade. This particular volume discusses potential measurements, plasma confinement, and hot electron and ion physics. 230 refs

Comparison of traditional low-dose-rate to optimized and nonoptimized high-dose-rate tandem and ovoid dosimetry

International Nuclear Information System (INIS)

Decker, William E.; Erickson, Beth; Albano, Katherine; Gillin, Michael

2001-01-01

Purpose: Few dose specification guidelines exist when attempting to perform high-dose-rate (HDR) dosimetry. The purpose of this study was to model low-dose-rate (LDR) dosimetry, using parameters common in HDR dosimetry, to achieve the 'pear-shape' dose distribution achieved with LDR tandem and ovoid applications. Methods and Materials: Radiographs of Fletcher-Suit LDR applicators and Nucletron 'Fletcher-like' HDR applicators were taken with the applicators in an idealized geometry. Traditional Fletcher loadings of 3M Cs-137 sources and the Theratronics Planning System were used for LDR dosimetry. HDR dosimetry was performed using the Nucletron Microselectron HDR UPS V11.22 with an Ir-192 source. Dose optimization points were initially located along a line 2 cm lateral to the tandem, beginning at the tandem tip at 0.5-cm intervals, ending at the sail, and optimized to 100% of the point A dose. A single dose optimization point was also placed laterally from the center of each ovoid equal to the radius of the ovoid (ovoid surface dose). For purposes of comparison, dose was also calculated for points A and B, and a point located 1 cm superior to the tandem tip in the plane of the tandem, (point F). Four- and 6-cm tandem lengths and 2.0-, 2.5-, and 3.0-cm ovoid diameters were used for this study. Based on initial findings, dose optimization schemes were developed to best approximate LDR dosimetry. Finally, radiographs were obtained of HDR applications in two patients. These radiographs were used to compare the optimization schemes with 'nonoptimized' treatment plans. Results: Calculated doses for points A and B were similar for LDR, optimized HDR, and nonoptimized HDR. The optimization scheme that used tapered dose points at the tandem tip and optimized a single ovoid surface point on each ovoid to 170% of point A resulted in a good approximation of LDR dosimetry. Nonoptimized HDR resulted in higher doses at point F, the bladder, and at points lateral to the tandem tip

Understanding Anaplasmataceae pathogenesis using ‘Omics’ approaches

Directory of Open Access Journals (Sweden)

Ludovic ePruneau

2014-07-01

Full Text Available This paper examines how Omics approaches improve our understanding of Anaplasmataceae pathogenesis, through a global and integrative strategy to identify genes and proteins involved in biochemical pathways key for pathogen-host-vector interactions.The Anaplasmataceae family comprises obligate intracellular bacteria mainly transmitted by arthropods. These bacteria are responsible for major human and animal endemic and emerging infectious diseases with important economic and public health impacts. In order to improve disease control strategies, it is essential to better understand their pathogenesis. Our work focused on four Anaplasmataceae, which cause important animal, human and zoonotic diseases: Anaplasma marginale, A. phagocytophilum, Ehrlichia chaffeensis and E. ruminantium. Wolbachia spp. an endosymbiont of arthropods was also included in this review as a model of a non-pathogenic Anaplasmataceae.A gap analysis on Omics approaches on Anaplasmataceae was performed, which highlighted a lack of studies on the genes and proteins involved in the infection of hosts and vectors. Furthermore, most of the studies have been done on the pathogen itself, mainly on infectious free-living forms and rarely on intracellular forms. In order to perform a transcriptomic analysis of the intracellular stage of development, researchers developed methods to enrich bacterial transcripts from infected cells. These methods are described in this paper. Bacterial genes encoding outer membrane proteins, post-translational modifications, eukaryotic repeated motif proteins, proteins involved in osmotic and oxidative stress and hypothetical proteins have been identified to play a key role in Anaplasmataceae pathogenesis. Further investigations on the function of these outer membrane proteins and hypothetical proteins will be essential to confirm their role in the pathogenesis. Our work underlines the need for further studies in this domain and on host and vector responses

Tandem Carbocupration/Oxygenation of Terminal Alkynes

Science.gov (United States)

Zhang, Donghui; Ready, Joseph M.

2008-01-01

A direct and general synthesis of α-branched aldehydes and their enol derivatives is described. Carbocupration of terminal alkynes and subsequent oxygenation with lithium tert-butyl peroxide generates a metallo-enolate. Trapping with various electrophiles provides α-branched aldehydes or stereo-defined trisubstituted enol esters or silyl ethers. The tandem carbocupration/oxygenation tolerates alkyl and silyl ethers, esters and tertiary amines. The reaction is effective with organocopper complexes derived from primary, secondary and tertiary Grignard reagents and from n-butyllithium. PMID:16321021

Transcription of highly repetitive tandemly organized DNA in amphibians and birds: A historical overview and modern concepts.

Science.gov (United States)

Trofimova, Irina; Krasikova, Alla

2016-12-01

Tandemly organized highly repetitive DNA sequences are crucial structural and functional elements of eukaryotic genomes. Despite extensive evidence, satellite DNA remains an enigmatic part of the eukaryotic genome, with biological role and significance of tandem repeat transcripts remaining rather obscure. Data on tandem repeats transcription in amphibian and avian model organisms is fragmentary despite their genomes being thoroughly characterized. Review systematically covers historical and modern data on transcription of amphibian and avian satellite DNA in somatic cells and during meiosis when chromosomes acquire special lampbrush form. We highlight how transcription of tandemly repetitive DNA sequences is organized in interphase nucleus and on lampbrush chromosomes. We offer LTR-activation hypotheses of widespread satellite DNA transcription initiation during oogenesis. Recent explanations are provided for the significance of high-yield production of non-coding RNA derived from tandemly organized highly repetitive DNA. In many cases the data on the transcription of satellite DNA can be extrapolated from lampbrush chromosomes to interphase chromosomes. Lampbrush chromosomes with applied novel technical approaches such as superresolution imaging, chromosome microdissection followed by high-throughput sequencing, dynamic observation in life-like conditions provide amazing opportunities for investigation mechanisms of the satellite DNA transcription.

Oak Ridge 25URC tandem accelerator 1994 SNEAP lab report

International Nuclear Information System (INIS)

Alton, G.D.; Dinehart, M.R.; Dowling, D.T.

1994-01-01

The 25URC tandem accelerator is still in shut-down mode until the facility is reconfigured to produce radioactive ion beams (RIBs). Again, the authors have operated approximately 200 hours for ion implantation studies in support of RIB development. Operation of the accelerator has been generally very reliable with most problems being associated with power supplies and components located outside the accelerator. The major operational problem this year was the development of internal shorts in the coils of the energy-analyzing magnet which caused beam instability. The major development activity for the tandem accelerator was the replacement of the corona-point voltage-grading system with resistors. Several milestones for the RIB project have been met since SNEAP 1993. The high-voltage platforms have been built and tested at the required 300 kV. Most equipment has been installed on the platforms so that the first beam can be developed using the Mark I target-ion source. This ion source was characterized on the ion source test facility before moving it to the platform. The second-stage mass-separator magnets have been specified and the contract has been awarded to Sigma Phi. The final optics design for the beam line from the second-stage separator to the tandem accelerator is being completed and equipment and controls are being procured

Summary of results from the Tandem Mirror Experiment (TMX)

International Nuclear Information System (INIS)

Simonen, T.C.

1981-01-01

This report summarizes results from the successful experimental operation of the Tandem Mirror Experiment (TMX) over the period October 1978 through September 1980. The experimental program, summarized by the DOE milestones given in Table 1-1, had three basic phases: (1) an 8-month checkout period, October 1978 through May 1979; (2) a 6-month initial period of operation, June through November 1979, during which the basic principles of the tandem configuration were demonstrated (i.e., plasma confinement was improved over that of a single-cell mirror); and (3) a 10-month period, December 1979 through September 1980, during which the initial TMX results were corroborated by additional diagnostic measurements and many detailed physics investigations were carried out. This report summarizes the early results, presents results of recent data analysis, and outlines areas of ongoing research and data analysis which will be reported in future journal publications

TMX-U [Tandem Mirror Experiment-Upgrade]: Final report, Volume 2

International Nuclear Information System (INIS)

Porter, G.D.

1988-01-01

This paper discusses the plasma control and the physics accomplishments of the Tandem Mirror Experiment-Upgrade. This particular volume discusses fueling, ion heating, Fokker-Planck modeling, plasma stability and technical development. 270 refs

Beam transport calculations for the EN tandem installation

International Nuclear Information System (INIS)

Sparks, R.J.

1980-12-01

Transport of a charged particle beam through the new EN tandem accelerator installation of the Institute of Nuclear Sciences has been analysed using simplified mathematical models. The purpose is to identify the factors affecting transmission of the beam, and to arrive at a design for the system to inject the beam into the accelerator

Stochastic motion of particles in tandem mirror devices

International Nuclear Information System (INIS)

Ichikawa, Y.H.; Kamimura, T.

1982-01-01

Stochastic motion of particles in tandem mirror devices is examined on basis of a nonlinear mapping of particle positions on the equatorial plane. Local stability analysis provides detailed informations on particle trajectories. The rate of stochastic plasma diffusion is estimated from numerical observations of motions of particles over a large number of time steps. (author)

Study of cross-reactivity in serum samples from dogs positive for Leishmania sp., Babesia canis and Ehrlichia canis in enzyme-linked immunosorbent assay and indirect fluorescent antibody test Estudo da reatividade cruzada em amostras de soro de cães positivos para Leishmania sp., Babesia canis e Ehrlichia canis, pelo ensaio imunoenzimático indireto e pela reação de imunofluorescência indireta

Directory of Open Access Journals (Sweden)

Trícia Maria F. de Sousa Oliveira

2008-03-01

Full Text Available To verify the presence of cross-reaction among leishmaniosis, ehrlichiosis and babesiosis in serological diagnostics used in human visceral leishmaniasis control programs, serum samples from leishmaniasis endemic and non-endemic areas were collected and tested by Indirect Fluorescent Antibody (IFAT and Enzyme-linked immunosorbent assay (ELISA. All serum samples from endemic areas were positive for Leishmania sp., by ELISA and IFAT, 51% positive for Babesia canis and 43% for Ehrlichia canis by IFAT. None of the serum samples from non-endemic areas were positive for Leishmania sp., by IFAT, but 67% were positive for B. canis and 78% for E. canis using the same test. When tested by ELISA for Leishmania sp., four samples from non-endemic area were positive. These dogs were then located and no clinical signs, parasites or antibody was detected in new tests for a six month period. Only one of these 4 samples was positive for B. canis by IFAT and ELISA and three for E. canis by IFAT. The results of the work suggest a co-infection in the endemic area and no serological cross-reaction among these parasites by IFAT and ELISA.Para verificar a existência de reação cruzada entre leishmaniose visceral, erliquiose e babesiose, nos testes sorológicos utilizados em programas de controle da leishmaniose visceral humana, amostras de soro canino provenientes de áreas endêmicas e não endêmicas para essa enfermidade, foram testadas pela Reação de Imunofluorescência (RIFI e Ensaio imunoenzimático (ELISA. Todos os soros provenientes de área endêmica foram positivos para Leishmania sp pelo ELISA e RIFI, 51% para Babesia canis e 43% para Ehrlichia canis pela RIFI. Pela RIFI, nenhum dos soros provenientes de área não endêmica foi positivo para Leishmania sp, sendo 67% positivos para B. canis e 78% para E. canis pelo mesmo teste. Quando testados pelo ELISA para Leishmania sp., quatro soros da área não endêmica foram positivos. Os cães foram localizados

Status of the tandem FEL project development in Israel

International Nuclear Information System (INIS)

Benzvi, I.; Sokolowski, J.; Jerby, E.; Chomski, D.; Ruschin, S.

1989-01-01

The authors report the status of a collaborative research project development aimed toward construction of an IR FEL based on the EN tandem electrostatic accelerator of the Weizmann Institute of Science. A preliminary feasibility demonstration project yielded encouraging progress in three aspects: (1) Electron gun and accelerator conversion: A 50-kV 1-A electron gun injector was designed, built, tested, and assembled on the 6-MeV tandem accelerator which was previously converted and conditioned to operate as an electron accelerator in a positively charged HV terminal configuration. Contrary to the configuration of the only electrostatic accelerator FEL demonstrated so far, the electron gun and multistage depressed collector are connected to the ground, and the wiggler is placed in the HV terminal of the straight geometry tandem accelerator. This configuration promises to provide a high current high quality e-beam. (2) Electron-beam transport: The first installation of the electron optical beam recovery system yielded transport efficiency of 80%. Substantial improvement is expected with planned electron optics modifications. An effect, highly significant for realizing long pulse (quasi-cw) FEL operation, was observed experimentally. Due to the damping effect of the accelerator column capacitance network, the voltage terminal stayed constant for milliseconds even with poor beam transport efficiency. This points to the possibility of developing a long pulse FEL which may operate at a single longitudinal mode. (3) Wiggler development: A conventional 4.4-cm period SmCo planar wiggler was acquired and evaluated using a recently constructed floating wire magnetic field measurement setup

[Clinical evaluation of TANDEM PSA in Japanese cases and comparison with other methods].

Science.gov (United States)

Kuriyama, M; Yamamoto, N; Shinoda, I; Kawada, Y; Akimoto, S; Shimazaki, J

1995-01-01

Clinical evaluation of TANDEM PSA which is the most frequently used prostate specific antigen (PSA) assay method in the world and a comparison with other methods were performed in Japanese cases in a cooperative research fashion. The minimum detectable level of the method was found to be 0.50 ng of PSA in one ml of serum and 1.9 ng/ml was regarded as the upper normal value in Japanese males. The distribution of serum PSA showed a significant difference between the benign prostate hypertrophy (BPH) cases and patients with stage C or D prostate cancer. The sero-diagnosis prostate cancer at an early stage with the TANDEM PSA was difficult. The correlation to other methods of PSA detection was very high. Furthermore, the clinical use of the method in following-up the clinical course of prostate cancer patients was very useful. These findings suggested that the PSA detection using TANDEM PSA is applicable even in Japanese cases although the upper cut-off level is decreased.

Probing Photocurrent Nonuniformities in the Subcells of Monolithic Perovskite/Silicon Tandem Solar Cells

KAUST Repository

Song, Zhaoning

2016-11-23

Perovskite/silicon tandem solar cells with high power conversion efficiencies have the potential to become a commercially viable photovoltaic option in the near future. However, device design and optimization is challenging because conventional characterization methods do not give clear feedback on the localized chemical and physical factors that limit performance within individual subcells, especially when stability and degradation is a concern. In this study, we use light beam induced current (LBIC) to probe photocurrent collection nonuniformities in the individual subcells of perovskite/silicon tandems. The choices of lasers and light biasing conditions allow efficiency-limiting effects relating to processing defects, optical interference within the individual cells, and the evolution of water-induced device degradation to be spatially resolved. The results reveal several types of microscopic defects and demonstrate that eliminating these and managing the optical properties within the multilayer structures will be important for future optimization of perovskite/silicon tandem solar cells.

Wolbachia: Evolutionary novelty in a rickettsial bacteria

Directory of Open Access Journals (Sweden)

Anderson Cort L

2001-11-01

Full Text Available Abstract Background Although closely related, the alpha-proteobacteria Wolbachia and the Rickettsiacae (Rickettsia and Ehrlichia, employ different evolutionary life history strategies. Wolbachia are obligate endocellular symbionts that infect an extraordinary host range and, in contrast to the infectious and pathogenic Rickettsia and Ehrlichia, profoundly influence host reproductive biology. Results Phylogenies of the Rickettsia, Ehrlichia, and Wolbachia were independently inferred from 16S rDNA sequences and GroEL amino acid sequences. Topologies inferred from both sets of sequence data were consistent with one another, and both indicate the genus Wolbachia shared a common ancestor most recently with Ehrlichia. These two genera are a sister group to the genus Rickettsia. Mapping biological properties onto this phylogeny reveals that manipulation of host reproduction, characteristic of Wolbachia strains, is a derived characteristic. This evolutionary novelty is accompanied by the loss of the ability to infect vertebrate hosts. Conclusions Because of the contrasting transmission strategies employed by each, Wolbachia is expected to maximize efficiency of vertical transmission, while Ehrlichia and Rickettsia will optimize horizontal transfer of infection. Wolbachia manipulation of host reproduction could thus be viewed as strategy employed by this bacterium to foster its own propagation via vertical transmission.

Kyushu University Tandem Accelerator Laboratory report, 1988-1990

International Nuclear Information System (INIS)

Sagara, Kenshi; Morinobu, Shunpei

1991-03-01

Ten years have elapsed since the first beam was obtained from the Kyushu University tandem accelerator. Although the laboratory has achieved successful scientific results, the performance of the accelerator has been on a decline mainly due to the aging. In the last two and a half years, the tandem accelerator has suffered from the fall of terminal voltage to around 8 MV. However, the experimental studies in the laboratory have been active. The utilization of the polarized beams of protons and deuterons to study the scattering of the p+d system, the use of heavy ion beam for the systematic search for the molecular resonance in relatively heavy systems and for the study on reaction mechanism, the use of both light and heavy ion beams for the studies on nuclear engineering, material science and geological science and so on were carried out. The gamma ray spectroscopic study on the state near yrast line was largely hampered by the accelerator troubles, instead, the collaboration with the Niels Bohr Institute provided a wonderful research ground for the studies. (K.I.)

GENETIC DIVERSITY OF TYPHA LATIFOLIA (TYPHACEAE) AND THE IMPACT OF POLLUTANTS EXAMINED WITH TANDEM-REPETITIVE DNA PROBES

Science.gov (United States)

Genetic diversity at variable-number-tandem-repeat (VNTR) loci was examined in the common cattail, Typha latifolia (Typhaceae), using three synthetic DNA probes composed of tandemly repeated "core" sequences (GACA, GATA, and GCAC). The principal objectives of this investigation w...

Zinc tin oxide as high-temperature stable recombination layer for mesoscopic perovskite/silicon monolithic tandem solar cells

KAUST Repository

Werner, Jé ré mie; Walter, Arnaud; Rucavado, Esteban; Moon, Soo Jin; Sacchetto, Davide; Rienaecker, Michael; Peibst, Robby; Brendel, Rolf; Niquille, Xavier; De Wolf, Stefaan; Lö per, Philipp; Morales-Masis, Monica; Nicolay, Sylvain; Niesen, Bjoern; Ballif, Christophe

2016-01-01

the concept, we fabricate monolithic tandem cells with mesoscopic top cell with up to 16% efficiency. We then investigate the effect of zinc tin oxide layer thickness variation, showing a strong influence on the optical interference pattern within the tandem

On the startup and shutdown of a tandem mirror reactor

International Nuclear Information System (INIS)

Chang, F.R.; DeCanio, F.T.; Fisher, J.L.; Madden, P.A.

1979-01-01

The startup and shutdown of a fusion reactor must be performed in such a way that the plasma remains MHD stable. In a tandem mirror the stability depends on a sufficiently high pressure ratio between the plugs and the central cell, of the order of 100. Control of the neutral beam input to the plugs by means of active feedback has been investigated to achieve an acceptable pressure ratio throughout the entire startup/shutdown transient. An algorithm to control the beam input power has been developed. The control law was subsequently tested in a tandem mirror simulation code. This paper describes the basic models incorporated in the simulation, as well as the derivation of the control algorithm. The simulation results are presented and the practicality of implementing the algorithm is discussed. 4 refs

Tandem white organic light-emitting diodes adopting a C60:rubrene charge generation layer

International Nuclear Information System (INIS)

Bi Wen-Tao; Wu Xiao-Ming; Hua Yu-Lin; Sun Jin-E; Xiao Zhi-Hui; Wang Li; Yin Shou-Gen

2014-01-01

Organic bulk heterojunction fullerence (C 60 ) doped 5, 6, 11, 12-tetraphenylnaphthacene (rubrene) as the high quality charge generation layer (CGL) with high transparency and superior charge generating capability for tandem organic light emitting diodes (OLEDs) is developed. This CGL shows excellent optical transparency about 90%, which can reduce the optical interference effect formed in tandem OLEDs. There is a stable white light emission including 468 nm and 500 nm peaks from the blue emitting layer and 620 nm peak from the red emitting layer in tandem white OLEDs. A high efficiency of about 17.4 cd/A and CIE coordinates of (0.40, 0.35) at 100 cd/m 2 and (0.36, 0.34) at 1000 cd/m 2 have been demonstrated by employing the developed CGL, respectively. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Beam transfer lines for the Tandem-superconducting cyclotron at Lab. Nazionale del Sud

International Nuclear Information System (INIS)

Calabretta, L.; Cuttone, G.; DiBernardo, P.; Giove, D.; Raia, G.; Yan, C.; Cao, L.; Liu, K.

1988-01-01

At the L.N.S. an MP-Tandem will be used as injector for the Superconducting Cyclotron. This paper describes the handling beam system for the Superconducting Cyclotron. All the lines are designed to be achromatic. Home made beam profile monitor is the main diagnostic device and its design and preliminary tests are presented. The distributed computer control for all the beam lines and bunching system is described too. The status of beam transfer line from tandem to S.C. and of bunching system is presented

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2014. Operation, Utilization and Technical Development of JRR-3, JRR-4, NSRR, Tandem Accelerator and RI Production Facility

International Nuclear Information System (INIS)

Osa, Akihiko; Imahashi, Masaki; Hirane, Nobuhiko; Motome, Yuiko; Tayama, Hidekazu; Tamura, Itaru; Harada, Yuko; Sakata, Mami; Kadokura, Masakazu; Takita, Chiharu

2017-02-01

The Department of Research Reactor and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3 (Japan Research Reactor No.3), JRR-4 (Japan Research Reactor No.4), NSRR (Nuclear Safety Research Reactor), Tandem Accelerator and RI Production Facility. This annual report describes the activities of our department in fiscal year of 2014. We carried out the operation and maintenance, utilization, upgrading of utilization techniques, safety administration, and international cooperation. Also contained are lists of publications, meetings, granted permissions on laws and regulations concerning atomic energy, outcomes in service and technical developments and so on. (author)

Annual report of Department of Research Reactor and Tandem Accelerator, JFY2013. Operation, Utilization and Technical Development of JRR-3, JRR-4, NSRR, Tandem Accelerator and RI Production Facility

International Nuclear Information System (INIS)

Kashima, Yoichi; Murayama, Yoji; Nakamura, Kiyoshi; Uno, Yuki; Hirane, Nobuhiko; Ohuchi, Hitoshi; Ishizaki, Nobuhiro; Matsumura, Taichi; Nagahori, Kazuhisa; Harada, Yuko; Kadokura, Masakazu; Machi, Sumire; Takita, Chiharu

2015-02-01

The Department of Research Reactor and Tandem Accelerator is in charge of the operation, utilization and technical development of JRR-3(Japan Research Reactor No.3), JRR-4(Japan Research Reactor No.4), NSRR(Nuclear Safety Research Reactor), Tandem Accelerator and RI Production Facility. This annual report describes the activities of our department in fiscal year of 2013. We carried out the operation and maintenance, utilization, upgrading of utilization techniques, safety administration and international cooperation. Also contained are lists of publications, meetings, granted permissions on laws and regulations concerning atomic energy, outcomes in service and technical developments and so on. (author)

Novel tandem structure employing mesh-structured Cu2S counter electrode for enhanced performance of quantum dot-sensitized solar cells

International Nuclear Information System (INIS)

Yang, Yue-Yong; Zhang, Quan-Xin; Wang, Tian-Zi; Zhu, Li-Feng; Huang, Xiao-Ming; Zhang, Yi-Duo; Hu, Xing; Li, Dong-Mei; Luo, Yan-Hong; Meng, Qing-Bo

2013-01-01

Highlights: ► This is the first report on practical tandem structures for quantum dot-sensitized solar cells (QDSCs). ► Mesh-structured Cu 2 S counter electrode exhibits high catalytic activity and good transmittance. ► Influence of photoanode thickness on tandem QDSCs has been systematically studied. ► Tandem QDSCs shows higher photocurrent and efficiency as against the single-photoanode cell. ► This structure can achieve higher efficiency with different QD sensitizers for complementary spectral responses. -- Abstract: A practical tandem structure with a semitransparent mesh-structured Cu 2 S counter electrode sandwiched between two TiO 2 photoelectrodes has been designed for quantum dot-sensitized solar cells (QDSCs). The mesh-structured Cu 2 S counter electrode exhibits high catalytic activity for polysulfide electrolyte. CdS/CdSe quantum dot-sensitized TiO 2 films have been applied as both top and bottom photoelectrodes to testify the effectiveness of the tandem structure. The influence of the TiO 2 film thickness on the performance of the tandem cell has been systematically studied. The optimized tandem QDSC shows an improved photocurrent and 12-percent increase of efficiency over the top cell with a 4.7 μm thick top cell and an 11.0 μm thick bottom cell, presenting a new effective approach towards highly efficient QDSCs

Environmentally Printing Efficient Organic Tandem Solar Cells with High Fill Factors: A Guideline Towards 20% Power Conversion Efficiency

DEFF Research Database (Denmark)

Li, Ning; Baran, Derya; Spyropoulos, George D.

2014-01-01

presents a major challenge. The reported high PCE values from lab-scale spin-coated devices are, of course, representative, but not helpful for commercialization. Here, organic tandem solar cells with exceptionally high fill factors and PCE values of 7.66% (on glass) and 5.56% (on flexible substrate...... to enhance the power conversion efficiency (PCE). However, due to the undeveloped deposition techniques, the challenges in ink formulation as well as the lack of commercially available high performance active materials, roll-to-roll fabrication of highly efficient organic tandem solar cells currently......), which are the highest values for the solution-processed tandem solar cells fabricated by a mass-production compatible coating technique under ambient conditions, are demonstrated. To predict the highest possible performance of tandem solar cells, optical simulation based on experimentally feasible...

Tandem Solid Phase Extraction for the Determination of Pharmaceuticals in Wastewater

International Nuclear Information System (INIS)

Licaberth Ismail; Rozita Osman; Norashikin Saim

2013-01-01

In this study, a simple and rapid tandem solid phase extraction (SPE) was developed for the analysis of seven pharmaceuticals (acetaminophen, caffeine, carbamazepine, diclofenac, naproxen, ibuprofen and metaprolol) in wastewater sample. The novel aspect of coupling SPE cartridge in tandem is the ability to simplify the SPE procedure (sample introduction step) as no single sorbent was able to retain and concentrate all selected compounds since these compounds are of different physicochemical properties. A tandem SPE cartridges using Oasis HLB and octadecyl bonded silica (C 18 ) was found to be efficient with the advantages of minimizing sample volume and reducing analysis time. Using this approach, carbamazepine, diclofenac, naproxen and metaprolol were trapped in the Oasis HLB while acetaminophen, caffeine and ibuprofen were trapped in the second cartridge (C 18 ). The instrumental limits of detection (LOD) ranged from 0.01 to 0.04 μg/ L and satisfactory recoveries were obtained between 76 % to 104 %. The calibration curves were linear from 0.1 to 5.0 μg/ mL, with correlation coefficients (R 2 ) in the range of 0.995 to 0.999. The developed method was applied to the analysis of pharmaceuticals in wastewater samples. The amount of pharmaceuticals detected in wastewater samples varied from 0.4 to 24.5 mg/ L. (author)

White-emissive tandem-type hybrid organic/polymer diodes with (0.33, 0.33) chromaticity coordinates.

Science.gov (United States)

Guo, Tzung-Fang; Wen, Ten-Chin; Huang, Yi-Shun; Lin, Ming-Wei; Tsou, Chuan-Cheng; Chung, Chia-Tin

2009-11-09

This study reports fabrication of white-emissive, tandem-type, hybrid organic/polymer light-emitting diodes (O/PLED). The tandem devices are made by stacking a blue-emissive OLED on a yellow-emissive phenyl-substituted poly(para-phenylene vinylene) copolymer-based PLED and applying an organic oxide/Al/molybdenum oxide (MoO(3)) complex structure as a connecting structure or charge-generation layer (CGL). The organic oxide/Al/MoO(3) CGL functions as an effective junction interface for the transport and injection of opposite charge carriers through the stacked configuration. The electroluminescence (EL) spectra of the tandem-type devices can be tuned by varying the intensity of the emission in each emissive component to yield the visible-range spectra from 400 to 750 nm, with Commission Internationale de l'Eclairage chromaticity coordinates of (0.33, 0.33) and a high color rendering capacity as used for illumination. The EL spectra also exhibit good color stability under various bias conditions. The tandem-type device of emission with chromaticity coordinates, (0.30, 0.31), has maximum brightness and luminous efficiency over 25,000 cd/m(2) and approximately 4.2 cd/A, respectively.

State-dependent importance sampling for a Jackson tandem network

NARCIS (Netherlands)

Miretskiy, D.I.; Scheinhardt, W.R.W.; Mandjes, M.R.H.

2008-01-01

This paper considers importance sampling as a tool for rare-event simulation. The focus is on estimating the probability of overflow in the downstream queue of a Jacksonian two-node tandem queue – it is known that in this setting ‘traditional’ stateindependent importance-sampling distributions

State-dependent importance sampling for a Jackson tandem network

NARCIS (Netherlands)

D.I. Miretskiy; W.R.W. Scheinhardt (Werner); M.R.H. Mandjes (Michel)

2008-01-01

htmlabstractThis paper considers importance sampling as a tool for rare-event simulation. The focus is on estimating the probability of overflow in the downstream queue of a Jacksonian two-node tandem queue – it is known that in this setting ‘traditional’ stateindependent importance-sampling

Radiocarbon dating with the Chalk River MP Tandem accelerator

International Nuclear Information System (INIS)

Ball, G.C.; Andrews, H.R.; Brown, R.M.; Burn, N.; Davies, W.G.; Imahori, Y.; Milton, J.C.D.

1981-01-01

During the past three years an automated radiocarbon dating system based on the MP Tandem accelerator has been developed for the analysis of 14 C in groundwater samples from the nuclear waste disposal research program and other small samples of scientific interest. At the present time 14 C/ 12 C ratio measurements can be determined with an accuracy of about 5% and the system background levels (approx. 35000 to 45000 years) are totally determined by sample and/or ion source contamination. Our goal has been to develop a dedicated reliable system for routine analysis that will produce accurate results with a minimum expenditure of human resources and accelerator beam time. Improvements required to operate the tandem accelerator as a quantitative tool have also benefited the rest of the experimental nuclear physics program. The early evolution of the dating facility was described previously. This paper is a brief report of the current status at Chalk River

Tandem Mirror Experiment Upgrade (TMX-U) overview-recent events

International Nuclear Information System (INIS)

Calderon, M.O.; Bell, H.H.

1985-01-01

Since its construction and commissioning was completed in the winter of 1981, the Tandem Mirror Experiment Upgrade (TMX-U) has been conducting tandem mirror thermal barrier experiments. The work, following the fall of 1983 when strong plugging with thermal barriers was achieved, has been directed toward controlling radial transport and forming thermal barriers with high density and Beta. This paper describes the overall engineering component of these efforts. Major changes to the machine have included vacuum improvements, changes to the Electron and Ion Cyclotron Resonance Heating systems (ECRH and ICRH), and the installation of a Plasma Potential Control system (PPC) for radial transport reduction. TMX-U operates an extensive diagnostics system that acquires data from 21 types of diagnostic instruments with more than 600 channels, in addition to 246 machine parameters. The changes and additions will be presented. The closing section of this paper will describe the initial study work for a proposed TMX-U octupole configured machine

Use of TANDEM methodology for quality control in radiation protection; Aplicacao de metodologia TANDEM para controle de qualidade em radioprotecao

Energy Technology Data Exchange (ETDEWEB)

Mello, O.A.; Oliveira, I.R.; Leyton, F.; Nogueira, M.S., E-mail: mnogueira@cdtn.br [Centro de Desenvolvimeto da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Borges, F.L.S., E-mail: flavialuizaborges@yahoo.com.br [Vigilancia Sanitaria de Minas Gerais, Belo Horizonte, MG (Brazil); Joana, G.S., E-mail: georgia.joana@gmail.com [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil)

2014-07-01

Recent studies have indicated the increase of the incidence of lens opacities for low radiation doses. Considering epidemiological data, the International Commission on Radiological Protection (ICRP) issued a statement that changed the absorbed dose threshold for the eye lens. The statement also recommends a reduction in the dose limits to the eye lens for occupationally exposed persons; now it is considered to be 20 mSv in a year averaged over five years. For this research two types of thermoluminescent dosimeters TL were used in the construction of the curve tandem. (LiF-100H e LiF-200). For system calibration three monitors were irradiated for each radiation beam. The monitors were irradiated with 4 mGy kerma at 1.5 m from the focal point. The Tandem curve was obtained by the ratio between the values of the energy dependence curves of each dosimeter. Data obtained for the corresponding x-ray beams to radiation reference N60 to N120 are more accurate for determining the energy - steepest part of the curve. The results are shown similar to similar studies and confirm the possibility of using the method for determining the unknown energy radiation fields. (author)

Molecular ion acceleration using tandem accelerator

Energy Technology Data Exchange (ETDEWEB)

Saito, Yuichi; Mizuhashi, Kiyoshi; Tajima, Satoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

1996-12-01

In TIARA compound beam radiation system, cluster beams have been produced using 3 MV tandem accelerator (9SDH-2) to supply them to various radiation on injection experiments. Till now, productions of C{sub 2-8}, Si{sub 2-4} and O{sub 2} and their accelerations up to 6 MeV have been succeeded. This study aimed at production and acceleration of B{sub 2-4} and LiF. Anion clusters were produced using the conventional ion source of cesium sputter type. The proportions of atoms, molecules and clusters elicited from the ion source were varied depending on the material`s properties and the operating conditions of ion source such as sample temperature, sputter voltage and the shape of sample. The anion clusters were accelerated toward the high voltage terminal in the center of tandem accelerator, leading to cations through losing their electrons by the collision to N{sub 2} gas in a charge conversion cell at the terminal. Positively charged cluster ions could be obtained by modulating the pressure of N{sub 2} gas. Thus, B{sub 2} (64 nA), B{sub 3} (4.4 nA) and B{sub 4} (2.7 nA) have been produced and their maximum survival probabilities were higher than those of carbon or silicon clusters. In addition, the relationship between beam current and gas pressure was investigated for Bn (n = 2-4) and LiF. (M.N.)

SU-G-201-11: Exploring the Upper Limits of Dose Sculpting Capacity of the Novel Direction Modulated Brachytherapy (DMBT) Tandem Applicator

International Nuclear Information System (INIS)

Han, D; Safigholi, H; Soliman, A; Song, W

2016-01-01

Purpose: To explore and quantify the upper limits in dose sculpting capacity of the novel direction modulated brachytherapy (DMBT) tandem applicator compared with conventional tandem design for "1"9"2Ir-based HDR planning. Methods: The proposed DMBT tandem applicator is designed for image-guided adaptive brachytherapy (IGABT), especially MRI, of cervical cancer. It has 6 peripheral holes of 1.3-mm width, grooved along a 5.4-mm diameter nonmagnetic tungsten alloy rod of density 18.0 g/cc, capable of generating directional dose profiles – leading to enhanced dose sculpting capacity through inverse planning. The external dimensions are identical to that of conventional tandem design to ensure clinical compatibility. To explore the expansive dose sculpting capacity, we constructed a hypothetical circular target with 20-mm radius and positioned the DMBT and conventional tandems at the center. We then incrementally shifted the positions laterally away from the center of up to 15 mm, at 1-mm steps. The in-house coded gradient projection-based inverse planning system was then used to generate inverse optimized plans ensuring identical V100=100% coverage. Conformity index (CI) was calculated for all plans. Results: Overall, the DMBT tandem generates more conformal dose distributions than conventional tandem for all lateral positional shifts of 0-15 mm (CI=0.91–0.52 and 0.99–0.34, respectively), with an exception at the central position due to the ideal circular dose distribution, generated by the "1"9"2Ir, fitting tightly around the circular target (CI = 0.91 and 0.99, respectively). The DMBT tandem is able to generate dose conformity of CI>0.8 at up to 6-mm positional shift while the conventional tandem violates this past 2-mm shift. Also, the CI ratio (=DMBT/conv.) increases rapidly until about 8 mm and then stabilizes beyond. Conclusion: A substantial enhancement in the dose sculpting capacity has been demonstrated for the novel DMBT tandem applicator. While

SU-G-201-11: Exploring the Upper Limits of Dose Sculpting Capacity of the Novel Direction Modulated Brachytherapy (DMBT) Tandem Applicator

Energy Technology Data Exchange (ETDEWEB)

Han, D [University of California San Francisco, San Francisco, CA (United States); Department of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON (Canada); Safigholi, H; Soliman, A [Department of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON (Canada); Song, W [Department of Medical Physics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON (Canada); University of Toronto, Toronto, ON (Canada)

2016-06-15

Purpose: To explore and quantify the upper limits in dose sculpting capacity of the novel direction modulated brachytherapy (DMBT) tandem applicator compared with conventional tandem design for {sup 192}Ir-based HDR planning. Methods: The proposed DMBT tandem applicator is designed for image-guided adaptive brachytherapy (IGABT), especially MRI, of cervical cancer. It has 6 peripheral holes of 1.3-mm width, grooved along a 5.4-mm diameter nonmagnetic tungsten alloy rod of density 18.0 g/cc, capable of generating directional dose profiles – leading to enhanced dose sculpting capacity through inverse planning. The external dimensions are identical to that of conventional tandem design to ensure clinical compatibility. To explore the expansive dose sculpting capacity, we constructed a hypothetical circular target with 20-mm radius and positioned the DMBT and conventional tandems at the center. We then incrementally shifted the positions laterally away from the center of up to 15 mm, at 1-mm steps. The in-house coded gradient projection-based inverse planning system was then used to generate inverse optimized plans ensuring identical V100=100% coverage. Conformity index (CI) was calculated for all plans. Results: Overall, the DMBT tandem generates more conformal dose distributions than conventional tandem for all lateral positional shifts of 0-15 mm (CI=0.91–0.52 and 0.99–0.34, respectively), with an exception at the central position due to the ideal circular dose distribution, generated by the {sup 192}Ir, fitting tightly around the circular target (CI = 0.91 and 0.99, respectively). The DMBT tandem is able to generate dose conformity of CI>0.8 at up to 6-mm positional shift while the conventional tandem violates this past 2-mm shift. Also, the CI ratio (=DMBT/conv.) increases rapidly until about 8 mm and then stabilizes beyond. Conclusion: A substantial enhancement in the dose sculpting capacity has been demonstrated for the novel DMBT tandem applicator. While

Optimization of Recombination Layer in the Tunnel Junction of Amorphous Silicon Thin-Film Tandem Solar Cells

Directory of Open Access Journals (Sweden)

Yang-Shin Lin

2011-01-01

Full Text Available The amorphous silicon/amorphous silicon (a-Si/a-Si tandem solar cells have attracted much attention in recent years, due to the high efficiency and low manufacturing cost compared to the single-junction a-Si solar cells. In this paper, the tandem cells are fabricated by high-frequency plasma-enhanced chemical vapor deposition (HF-PECVD at 27.1 MHz. The effects of the recombination layer and the i-layer thickness matching on the cell performance have been investigated. The results show that the tandem cell with a p+ recombination layer and i2/i1 thickness ratio of 6 exhibits a maximum efficiency of 9.0% with the open-circuit voltage (Voc of 1.59 V, short-circuit current density (Jsc of 7.96 mA/cm2, and a fill factor (FF of 0.70. After light-soaking test, our a-Si/a-Si tandem cell with p+ recombination layer shows the excellent stability and the stabilized efficiency of 8.7%.

SU-F-T-633: Cyberknife Boost Versus Conventional Tandem and Ovoid Treatment for Cervical Cancer

Energy Technology Data Exchange (ETDEWEB)

Santoro, J; Witten, M; Haas, J [Winthrop University Hospital, Lynbrook, NY (United States)

2016-06-15

Purpose: Brachytherapy has been the standard of care for cervical cancer for 100 years. The treatment can be administered using an HDR (high dose rate) remote afterloader with a {sup 192}Ir source in an outpatient setting, a PDR afterloader with a {sup 192}Ir source, or with LDR manually loaded or a remote afterloader utilizing {sup 192}Ir or {sup 137}Cs sources in an inpatient setting. The procedure involves the placement of a tandem and ovoid, tandem and ring, or tandem and cylinder applicator in an operating room setting with the patient under general anesthesia. Inaccuracies introduced into the process occurring between placement of the applicator and actual delivery can introduce uncertainty into the actual dose delivered to the tumor and critical organs. In this study we seek to investigate the dosimetric difference between an SBRT-based radiotherapy boost and conventional Brachytherapy in treating cervical cancer. Methods: Five HDR tandem and ovoid patients were planned using the Brachyvision treatment planning system and treated in four fractions using the Varian Varisource afterloader (Varian Medical Systems). For the same cohort, the patient planning CTs were imported into Multiplan (Accuray Inc) and a dose/fractionation-equivalent CyberKnife SBRT plan was retrospectively generated. Dosimetric quantities such as target/CTV D90, V90, D2cc for rectum, bladder, and bowel were measured and compared between the two modalities. Results: The CTV D90 for the tandem and ovoid was 2540cGy (90.7%) and 3009cGy (107.5%) for the CyberKnife plan. The D2cc for the rectum, bladder, and bowel were 1576cGy, 1641cGy, and 996cGy for the tandem and ovoid and 1374cGy, 1564cGy, and 1547cGy for CyberKnife. Conclusion: The D2cc doses to critical structures are comparable in both modalities. The CTV coverage is far superior for the CyberKnife plan. The dose distribution for CyberKnife has the advantage of increased conformality and lower maximum CTV dose.

Moment approach to tandem mirror radial transport

International Nuclear Information System (INIS)

Siebert, K.D.; Callen, J.D.

1986-02-01

A moment approach is proposed for the study of tandem mirror radial transport in the resonant plateau regime. The salient features of the method are described with reference to axisymmetric tokamak transport theory. In particular, the importance of momentum conservation to the establishment of the azimuthal variations in the electrostatic potential is demonstrated. Also, an ad hoc drift kinetic equation is solved to determine parallel viscosity coefficients which are required to close the moment system

Tandem for power generation. New sandwich concentrator cell with over 30% efficiency; Im Tandem Strom erzeugen. Neue Mehrschicht-Konzentratorzelle erzielt ueber 30% Wirkungsgrad

Energy Technology Data Exchange (ETDEWEB)

Anon.

2000-11-01

The Fraunhofer-Institut fuer Solare Energiesysteme at Freiburg, Germany, claims a 'best ever' efficiency of a monolithic tandem concentrator solar cell with a sandwich structure based on gallium-indium arsenide and gallium-indium phosphide. The new solar cell can be produced in a single process based on an Aixtron AG (Aachen, Germany) separator which is also used for industrial production of solar cells for aerospace applications. [German] Das Fraunhofer-Institut fuer Solare Energiesysteme in Freiburg hat einen neuen Wirkungsgradrekord fuer monolithische Tandem-Konzentratorsolarzellen gemeldet. Die Wissenschaftler am Fraunhofer-Institut fuer Solare Energiesysteme (Fraunhofer ISE) haben neue Schichtstrukturen auf der Basis von Gallium-Indium-Arsenid und Gallium-Inidum-Phosphid entwickelt. Die neue Solarzelle kann in einem einzigen Prozess hergestellt werden. Fuer diesen Prozess setzen die Freiburger Solarzellenforscher eine Abscheideanlage der Firma Aixtron AG aus Aachen ein, wie sie auch in der Industrie zur Herstellung von Solarzellen fuer Anwendungen im Weltraum genutzt wird. (orig.)

Plasma Desorption Mass Spectrometry using TANDEM accelerator in National Industrial Research Inst. of Nagoya

Energy Technology Data Exchange (ETDEWEB)

Mizota, Takeshi; Nakao, Setsuo; Niwa, Hiroaki; Saito, Kazuo [Particle Beam Sceince Laboratory, Multi-Function Material Science Department, National Industrial Research Inst. of Nagoya, Nagoya (Japan)

2001-02-01

Plasma Desorption Mass Spectrometry (PDMS) analysis was studied using TANDEM accelerator. The heavy ions of MeV range emit the secondary ions of atoms, molecules, polymers and clusters from the irradiated samples without destruction. The analysis system of PDMS designed and set-up using a mass spectrometer of Time of Flight and the TANDEM accelerator. The system performance was tested for C-60 fullerene on the surface of the samples using 11.2 MeV {sup 28}Si beams produced by the TANDEM accelerator of 1.7MV. The result shows that the hydrogen and hydrocarbons can be analyzed in the range of 1amu unit. The resolution (M/{delta}M) of the Mass Spectrometry system is confirmed to be about 1000 from the separation of the 720 and 721amu peaks, which is attributed to the C-60 fullerene including {sup 13}C atoms. (H. Katsuta)

Solution Structure of the Tandem Acyl Carrier Protein Domains from a Polyunsaturated Fatty Acid Synthase Reveals Beads-on-a-String Configuration

KAUST Repository

Trujillo, Uldaeliz

2013-02-28

The polyunsaturated fatty acid (PUFA) synthases from deep-sea bacteria invariably contain multiple acyl carrier protein (ACP) domains in tandem. This conserved tandem arrangement has been implicated in both amplification of fatty acid production (additive effect) and in structural stabilization of the multidomain protein (synergistic effect). While the more accepted model is one in which domains act independently, recent reports suggest that ACP domains may form higher oligomers. Elucidating the three-dimensional structure of tandem arrangements may therefore give important insights into the functional relevance of these structures, and hence guide bioengineering strategies. In an effort to elucidate the three-dimensional structure of tandem repeats from deep-sea anaerobic bacteria, we have expressed and purified a fragment consisting of five tandem ACP domains from the PUFA synthase from Photobacterium profundum. Analysis of the tandem ACP fragment by analytical gel filtration chromatography showed a retention time suggestive of a multimeric protein. However, small angle X-ray scattering (SAXS) revealed that the multi-ACP fragment is an elongated monomer which does not form a globular unit. Stokes radii calculated from atomic monomeric SAXS models were comparable to those measured by analytical gel filtration chromatography, showing that in the gel filtration experiment, the molecular weight was overestimated due to the elongated protein shape. Thermal denaturation monitored by circular dichroism showed that unfolding of the tandem construct was not cooperative, and that the tandem arrangement did not stabilize the protein. Taken together, these data are consistent with an elongated beads-on-a-string arrangement of the tandem ACP domains in PUFA synthases, and speak against synergistic biocatalytic effects promoted by quaternary structuring. Thus, it is possible to envision bioengineering strategies which simply involve the artificial linking of multiple ACP

Solution structure of the tandem acyl carrier protein domains from a polyunsaturated fatty acid synthase reveals beads-on-a-string configuration.

Directory of Open Access Journals (Sweden)

Uldaeliz Trujillo

Full Text Available The polyunsaturated fatty acid (PUFA synthases from deep-sea bacteria invariably contain multiple acyl carrier protein (ACP domains in tandem. This conserved tandem arrangement has been implicated in both amplification of fatty acid production (additive effect and in structural stabilization of the multidomain protein (synergistic effect. While the more accepted model is one in which domains act independently, recent reports suggest that ACP domains may form higher oligomers. Elucidating the three-dimensional structure of tandem arrangements may therefore give important insights into the functional relevance of these structures, and hence guide bioengineering strategies. In an effort to elucidate the three-dimensional structure of tandem repeats from deep-sea anaerobic bacteria, we have expressed and purified a fragment consisting of five tandem ACP domains from the PUFA synthase from Photobacterium profundum. Analysis of the tandem ACP fragment by analytical gel filtration chromatography showed a retention time suggestive of a multimeric protein. However, small angle X-ray scattering (SAXS revealed that the multi-ACP fragment is an elongated monomer which does not form a globular unit. Stokes radii calculated from atomic monomeric SAXS models were comparable to those measured by analytical gel filtration chromatography, showing that in the gel filtration experiment, the molecular weight was overestimated due to the elongated protein shape. Thermal denaturation monitored by circular dichroism showed that unfolding of the tandem construct was not cooperative, and that the tandem arrangement did not stabilize the protein. Taken together, these data are consistent with an elongated beads-on-a-string arrangement of the tandem ACP domains in PUFA synthases, and speak against synergistic biocatalytic effects promoted by quaternary structuring. Thus, it is possible to envision bioengineering strategies which simply involve the artificial linking of

Solution Structure of the Tandem Acyl Carrier Protein Domains from a Polyunsaturated Fatty Acid Synthase Reveals Beads-on-a-String Configuration

KAUST Repository

Trujillo, Uldaeliz; Vá zquez-Rosa, Edwin; Oyola-Robles, Delise; Stagg, Loren J.; Vassallo, David A.; Vega, Irving E.; Arold, Stefan T.; Baerga-Ortiz, Abel

2013-01-01

The polyunsaturated fatty acid (PUFA) synthases from deep-sea bacteria invariably contain multiple acyl carrier protein (ACP) domains in tandem. This conserved tandem arrangement has been implicated in both amplification of fatty acid production (additive effect) and in structural stabilization of the multidomain protein (synergistic effect). While the more accepted model is one in which domains act independently, recent reports suggest that ACP domains may form higher oligomers. Elucidating the three-dimensional structure of tandem arrangements may therefore give important insights into the functional relevance of these structures, and hence guide bioengineering strategies. In an effort to elucidate the three-dimensional structure of tandem repeats from deep-sea anaerobic bacteria, we have expressed and purified a fragment consisting of five tandem ACP domains from the PUFA synthase from Photobacterium profundum. Analysis of the tandem ACP fragment by analytical gel filtration chromatography showed a retention time suggestive of a multimeric protein. However, small angle X-ray scattering (SAXS) revealed that the multi-ACP fragment is an elongated monomer which does not form a globular unit. Stokes radii calculated from atomic monomeric SAXS models were comparable to those measured by analytical gel filtration chromatography, showing that in the gel filtration experiment, the molecular weight was overestimated due to the elongated protein shape. Thermal denaturation monitored by circular dichroism showed that unfolding of the tandem construct was not cooperative, and that the tandem arrangement did not stabilize the protein. Taken together, these data are consistent with an elongated beads-on-a-string arrangement of the tandem ACP domains in PUFA synthases, and speak against synergistic biocatalytic effects promoted by quaternary structuring. Thus, it is possible to envision bioengineering strategies which simply involve the artificial linking of multiple ACP

Tandem neopentyl glycol maltosides (TNMs) for membrane protein stabilisation

DEFF Research Database (Denmark)

Bae, Hyoung Eun; Mortensen, Jonas S; Ribeiro, Orquidea

2016-01-01

A novel class of detergents, designated tandem neopentyl glycol maltosides (TNMs), were evaluated with four target membrane proteins. The best detergent varied depending on the target, but TNM-C12L and TNM-C11S were notable for their ability to confer increased membrane protein stability compared...

Diffractive intermediate layer enables broadband light trapping for high efficiency ultrathin c-Si tandem cells

Energy Technology Data Exchange (ETDEWEB)

Li, Guijun, E-mail: gliad@connect.ust.hk; Ho, Jacob Y. L.; Li, He; Kwok, Hoi-Sing [State Key Laboratory on Advanced Displays and Optoelectronics Technologies, Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)

2014-06-09

Light management through the intermediate reflector in the tandem cell configuration is of great practical importance for achieving high stable efficiency and also low cost production. So far, however, the intermediate reflectors employed currently are mainly focused on the light absorption enhancement of the top cell. Here, we present a diffractive intermediate layer that allows for light trapping over a broadband wavelength for the ultrathin c-Si tandem solar cell. Compared with the standard intermediate reflector, this nanoscale architectural intermediate layer results in a 35% and 21% remarkable enhancement of the light absorption in the top (400–800 nm) and bottom (800–1100 nm) cells simultaneously, and ultrathin c-Si tandem cells with impressive conversion efficiency of 13.3% are made on the glass substrate.

Diffractive intermediate layer enables broadband light trapping for high efficiency ultrathin c-Si tandem cells

International Nuclear Information System (INIS)

Li, Guijun; Ho, Jacob Y. L.; Li, He; Kwok, Hoi-Sing

2014-01-01

Light management through the intermediate reflector in the tandem cell configuration is of great practical importance for achieving high stable efficiency and also low cost production. So far, however, the intermediate reflectors employed currently are mainly focused on the light absorption enhancement of the top cell. Here, we present a diffractive intermediate layer that allows for light trapping over a broadband wavelength for the ultrathin c-Si tandem solar cell. Compared with the standard intermediate reflector, this nanoscale architectural intermediate layer results in a 35% and 21% remarkable enhancement of the light absorption in the top (400–800 nm) and bottom (800–1100 nm) cells simultaneously, and ultrathin c-Si tandem cells with impressive conversion efficiency of 13.3% are made on the glass substrate.

Flexible organic tandem solar modules: a story of up-scaling

Science.gov (United States)

Spyropoulos, George D.; Kubis, Peter; Li, Ning; Lucera, Luca; Salvador, Michael; Baran, Derya; Machui, Florian; Ameri, Tayebeh; Voigt, Monika M.; Brabec, Christoph J.

2014-10-01

The competition in the field of solar energy between Organic Photovoltaics (OPVs) and several Inorganic Photovoltaic technologies is continuously increasing to reach the ultimate purpose of energy supply from inexpensive and easily manufactured solar cell units. Solution-processed printing techniques on flexible substrates attach a tremendous opportunity to the OPVs for the accomplishment of low-cost and large area applications. Furthermore, tandem architectures came to boost up even more OPVs by increasing the photon-harvesting properties of the device. In this work, we demonstrate the road of realizing flexible organic tandem solar modules constructed by a fully roll-to-roll compatible processing. The modules exhibit an efficiency of 5.4% with geometrical fill factors beyond 80% and minimized interconnection-resistance losses. The processing involves low temperature (<70 °C), coating methods compatible with slot die coating and high speed and precision laser patterning.

The TESS [Tandem Experiment Simulation Studies] computer code user's manual

International Nuclear Information System (INIS)

Procassini, R.J.

1990-01-01

TESS (Tandem Experiment Simulation Studies) is a one-dimensional, bounded particle-in-cell (PIC) simulation code designed to investigate the confinement and transport of plasma in a magnetic mirror device, including tandem mirror configurations. Mirror plasmas may be modeled in a system which includes an applied magnetic field and/or a self-consistent or applied electrostatic potential. The PIC code TESS is similar to the PIC code DIPSI (Direct Implicit Plasma Surface Interactions) which is designed to study plasma transport to and interaction with a solid surface. The codes TESS and DIPSI are direct descendants of the PIC code ES1 that was created by A. B. Langdon. This document provides the user with a brief description of the methods used in the code and a tutorial on the use of the code. 10 refs., 2 tabs

Tandem malonate-based glucosides (TMGs) for membrane protein structural studies

DEFF Research Database (Denmark)

Hussain, Hazrat; Mortensen, Jonas S.; Du, Yang

2017-01-01

class of glucoside amphiphiles, designated tandem malonate-based glucosides (TMGs). A few TMG agents proved effective at both stabilizing a range of membrane proteins and extracting proteins from the membrane environment. These favourable characteristics, along with synthetic convenience, indicate...

A New Synthetic Route to Dihydrobenzopyran Via Tandem Demethylation Cyclisation

Directory of Open Access Journals (Sweden)

G. Shanmugam

2000-06-01

Full Text Available A tandem demethylation-cyclisation reaction resulting in the formation of pyran rings using AlCl3/EtSH reagent under mild reaction conditions is reported. X-ray diffraction studies on the intermediate support the suggested mechanism.

Enhanced antibody-dependent cellular phagocytosis by chimeric monoclonal antibodies with tandemly repeated Fc domains.

Science.gov (United States)

Nagashima, Hiroaki; Ootsubo, Michiko; Fukazawa, Mizuki; Motoi, Sotaro; Konakahara, Shu; Masuho, Yasuhiko

2011-04-01

We previously reported that chimeric monoclonal antibodies (mAbs) with tandemly repeated Fc domains, which were developed by introducing tandem repeats of Fc domains downstream of 2 Fab domains, augmented binding avidities for all Fcγ receptors, resulting in enhanced antibody (Ab)-dependent cellular cytotoxicity. Here we investigated regarding Ab-dependent cellular phagocytosis (ADCP) mediated by these chimeric mAbs, which is considered one of the most important mechanisms that kills tumor cells, using two-color flow cytometric methods. ADCP mediated by T3-Ab, a chimeric mAb with 3 tandemly repeated Fc domains, was 5 times more potent than that by native anti-CD20 M-Ab (M-Ab hereafter). Furthermore, T3-Ab-mediated ADCP was resistant to competitive inhibition by intravenous Ig (IVIG), although M-Ab-mediated ADCP decreased in the presence of IVIG. An Fcγ receptor-blocking study demonstrated that T3-Ab mediated ADCP via both FcγRIA and FcγRIIA, whereas M-Ab mediated ADCP exclusively via FcγRIA. These results suggest that chimeric mAbs with tandemly repeated Fc domains enhance ADCP as well as ADCC, and that Fc multimerization may significantly enhance the efficacy of therapeutic Abs. Copyright © 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Note on a tandem queue with delayed server release

NARCIS (Netherlands)

Nawijn, W.M.

2000-01-01

We consider a tandem queue with two stations. The first station is an $s$-server queue with Poisson arrivals and exponential service times. After terminating his service in the first station, a customer enters the second station to require service at a single server, while in the meantime he is

State-dependent importance sampling for a slowdown tandem queue

NARCIS (Netherlands)

Miretskiy, D.I.; Scheinhardt, W.R.W.; Mandjes, M.R.H.

2011-01-01

In this paper we investigate an advanced variant of the classical (Jackson) tandem queue, viz. a two-node system with server slowdown. By this mechanism, the service speed of the upstream queue is reduced as soon as the number of jobs in the downstream queue reaches some pre-specified threshold. We

A tandem queue with server slow-down and blocking

NARCIS (Netherlands)

van Foreest, N.D.; van Ommeren, Jan C.W.; Mandjes, M.R.H.; Scheinhardt, Willem R.W.

2005-01-01

We consider two variants of a two-station tandem network with blocking. In both variants the first server ceases to work when the queue length at the second station hits a 'blocking threshold.' In addition, in variant 2 the first server decreases its service rate when the second queue exceeds a

A tandem queue with server slow-down and blocking.

NARCIS (Netherlands)

van Foreest, N.; van Ommeren, J.C.; Mandjes, M.R.H.; Scheinhardt, W.

2005-01-01

We consider two variants of a two-station tandem network with blocking. In both variants the first server ceases to work when the queue length at the second station hits a 'blocking threshold.' In addition, in variant 2 the first server decreases its service rate when the second queue exceeds a

Three-dimensional photonic crystals as intermediate filter for thin-film tandem solar cells

Science.gov (United States)

Bielawny, Andreas; Miclea, Paul T.; Wehrspohn, Ralf B.; Lee, Seung-Mo; Knez, Mato; Rockstuhl, Carsten; Lisca, Marian; Lederer, Falk L.; Carius, Reinhard

2008-04-01

The concept of a 3D photonic crystal structure as diffractive and spectrally selective intermediate filter within 'micromorphous' (a-Si/μc-Si) tandem solar cells has been investigated numerically and experimentally. Our device aims for the enhancement of the optical pathway of incident light within the amorphous silicon top cell in its spectral region of low absorption. From our previous simulations, we expect a significant improvement of the tandem cell efficiency of about absolutely 1.3%. This increases the efficiency for a typical a-Si / μc-Si tandem cell from 11.1% to 12.4%, as a result of the optical current-matching of the two junctions. We suggest as wavelength-selective optical element a 3D-structured optical thin-film, prepared by self-organized artificial opal templates and replicated with atomic layer deposition. The resulting samples are highly periodic thin-film inverted opals made of conducting and transparent zinc-oxide. We describe the fabrication processes and compare experimental data on the optical properties in reflection and transmission with our simulations and photonic band structure calculations.

Maximizing tandem solar cell power extraction using a three-terminal design

Energy Technology Data Exchange (ETDEWEB)

Warren, Emily L. [National Renewable Energy Lab; USA; Deceglie, Michael G. [National Renewable Energy Lab; USA; Rienäcker, Michael [Institute for Solar Energy Research Hamelin; Germany; Peibst, Robby [Institute for Solar Energy Research Hamelin; Germany; Tamboli, Adele C. [National Renewable Energy Lab; USA; Stradins, Paul [National Renewable Energy Lab; USA

2018-01-01

Three-terminal tandem solar cells can provide a robust operating mechanism to efficiently capture the solar spectrum without the need to current match sub-cells or fabricate complicated metal interconnects.

Argonne National Laboratory 1980-1981 tandem-linac accelerator report

International Nuclear Information System (INIS)

Hartog, P.D.; Pardo, R.; Munson, F.; Heath, C.

1981-01-01

Performance of the facility is discussed. The FN tandem Van de Graaff is now used as an injector for the superconducting linac; heavy-ion beams are being injected. Stripper foil development is described, with fabrication by arc evaporation and by RF discharge compared. Facility modifications, such as the control room, are discussed

Cable systems for experimental facilities in JAERI TANDEM ACCELERATOR BUILDING

International Nuclear Information System (INIS)

Tukihashi, Yoshihiro; Yoshida, Tadashi; Takekoshi, Eiko

1979-03-01

Measuring cable systems for experimental facilities in JAERI TANDEM ACCELERATOR BUILDING were completed recently. Measures are taken to prevent penetration of noises into the measuring systems. The cable systems are described in detail, including power supplies and grounding for the measuring systems. (author)

Status of tandem-mirror confinement

International Nuclear Information System (INIS)

Baldwin, D.E.

1983-01-01

Recent end-stopping experiments in TMX-Upgrade show strong plugging of the central cell by lower-density plugs, requiring both electron-cyclotron heating (ECRH) and 47 0 neutral-beam injection, consistent with the thermal-barrier concept. These experiments have low density (n 12 cm -3 ) due to inefficient ECRH power coupling. Hot-ion and hot-electron buildup are consistent with Fokker-Planck calculations. No ion-cyclotron activity is observed in the plugs; occasional electron-cyclotron activity is observed. With plugging, axial lifetimes (tau/sub parallel/ > 40 ms) are larger than radial (tau/sub perpendicular/ = 5 to 10 ms) due to observed non-ambipolar ion transport. Recent tandem-mirror theoretical activities are also surveyed

Crystalline silicon solar cell with front and rear polysilicon passivated contacts as bottom cell for hybrid tandems

NARCIS (Netherlands)

Luxembourg, S.L.; Zhang, D.; Wu, Y.; Najafi, M.; Zardetto, V.; Verhees, W.; Burgers, A.R.; Veenstra, S.; Geerligs, L.J.

2017-01-01

In this paper we analyze and model perovskite/c-Si tandem cells with front and rear polySi passivated contacts on the bottom cell. A high-efficiency tandem approach will benefit from the high Voc potential of a c-Si bottom cell with front and rear polySi passivated contacts while the combination

Round-Robin Studies on Roll-Processed ITO-free Organic Tandem Solar Cells Combined with Inter-Laboratory Stability Studies

DEFF Research Database (Denmark)

Livi, Francesco; Søndergaard, Roar R.; Andersen, Thomas Rieks

2015-01-01

Roll-processed, indium tin oxide (ITO)-free, flexible, organic tandem solar cells and modules have been realized and used in round-robin studies as well as in parallel inter-laboratory stability studies. The tandem cells/modules show no significant difference in comparison to their single...

Remote maintenance of tandem mirror hybrid coils

International Nuclear Information System (INIS)

Dietz, L.P.

1983-01-01

Hybrid Coils (superconducting coils with normal conducting inserts) are being employed with increasing frequency on Tandem Mirror Devices to obtain high field strengths. The normal conducting copper inserts are short lived in comparison to their encircling superconductors. It becomes desirable, therefore, to devise design features and maintenance procedures to replace the inner normal conducting coils without simultaneously replacing the longer lived (and significantly more costly) superconducting coils. The high neutron wall loadings require that the task be accomplished by remote control. The approach is to permanently mount the coil assemblies on track mounted carriages which serve, during machine operation merely as structural supports, but during maintenance procedures as moveable transport devices. The carriages incorporate all necessary provisions to facilitate remote maintenance operations and to adjust and align the coil assemblies with respect to adjacent machine components. The vacuum vessel is severed on both sides of the hybrid coil by means of a remote cutting machine. The entire coil is transported horizontally, normal to the machine axis to a nearby repair station. Prepositioned carriage mounted repair equipment at the repair station withdraws the damaged normal coil as a single entity and inserts a preassembled spare unit. The repaired hybrid coil is reassembled to the reactor. A cost and risk effective procedure has been evolved to maintain one of the more critical components of a Tandem Mirror Machine

Optimization and simulation of tandem column supercritical fluid chromatography separations using column back pressure as a unique parameter.

Science.gov (United States)

Wang, Chunlei; Tymiak, Adrienne A; Zhang, Yingru

2014-04-15

Tandem column supercritical fluid chromatography (SFC) has demonstrated to be a useful technique to resolve complex mixtures by serially coupling two columns of different selectivity. The overall selectivity of a tandem column separation is the retention time weighted average of selectivity from each coupled column. Currently, the method development merely relies on extensive screenings and is often a hit-or-miss process. No attention is paid to independently adjust retention and selectivity contributions from individual columns. In this study, we show how tandem column SFC selectivity can be optimized by changing relative dimensions (length or inner diameter) of the coupled columns. Moreover, we apply column back pressure as a unique parameter for SFC optimization. Continuous tuning of tandem column SFC selectivity is illustrated through column back pressure adjustments of the upstream column, for the first time. In addition, we show how and why changing coupling order of the columns can produce dramatically different separations. Using the empirical mathematical equation derived in our previous study, we also demonstrate a simulation of tandem column separations based on a single retention time measurement on each column. The simulation compares well with experimental results and correctly predicts column order and back pressure effects on the separations. Finally, considerations on instrument and column hardware requirements are discussed.

JAEA-Tokai tandem annual report 2012. April 1, 2012 - March 31, 2013

International Nuclear Information System (INIS)

Nishio, Katsuhisa; Tsukada, Kazuaki; Koura, Hiroyuki

2014-03-01

The JAEA-Tokai tandem accelerator complex has been used in various research fields such as nuclear science and material science by researchers not only of JAEA but also from universities, research institutes and industrial companies. This annual report covers developments of accelerators and research activities carried out using the tandem accelerator and superconducting booster from April 1, 2012 to March 31, 2013. Thirty-one summary reports were categorized into seven research/development fields: (1) accelerator operation and development, (2) nuclear structure, (3) nuclear reaction, (4) nuclear chemistry, (5) nuclear theory, (6) atomic physics and solid state physics, (7) radiation effects in materials. This report also lists publications, meetings, personnel, committee members, cooperative researches and common use programs. (author)

Reconditioning of the Cologne tandem after a fire at the ion source

International Nuclear Information System (INIS)

Dewald, A.; Steinert, L.

1988-01-01

In summer 1984 a fire broke out at the duoplasmatron ion source on the Cologne tandem accelerator. HCl from burnt PVC caused enormous damage by corrosion. After reconditioning the accelerator and following some improvements it was possible to operate the tandem more reliably at 9.5 MV than previously at 8 MV. Work is in progress to rebuild the injector in order to replace the inhomogeneous voltage divider at the entrance of the first tube by a homogeneous one. In addition a 90 0 injector with injection energy increased from 80 keV to 180 keV is planned. Since 1986 the Rossendorf sputter source MISS-483 has been in standard operation. (orig.)

Combined heat and power plants with parallel tandem steam turbines; Smaaskalig kraftvaerme med parallellkopplade tandemturbiner

Energy Technology Data Exchange (ETDEWEB)

Steinwall, Pontus; Norstroem, Urban; Pettersson, Camilla; Oesterlin, Erik

2004-12-01

We investigate the technical and economical conditions for a concept with parallel coupled tandem turbines in small scale combined heat and power plants fired with bio-fuel and waste. Performance and heat production costs at varying electricity prices for the concept with two smaller tandem coupled steam turbines has been compared to the traditional concept with one single multi-staged turbine. Three different types of plants have been investigated: - Bio fuelled CHP plant with thermal capacity of 15 MW{sub th}; - Waste fired CHP plant with thermal capacity of 20 MW{sub th}; - Bio fuelled CHP plant with thermal capacity of 25 MW{sub th}. The simple steam turbines (Curtis turbines) used in the tandem arrangement has an isentropic efficiency of about 49 to 53% compared to the multi-staged steam turbines with isentropic efficiency in the range of 59% to 81%. The lower isentropic efficiency for the single staged turbines is to some extent compensated at partial load when one of the two turbines can be shut down leading to better operational conditions for the one still in operation. For concepts with saturated steam at partial load below 50% the tandem arrangements presents higher electricity efficiency than the conventional single turbine alternative. The difference in annual production of electricity is therefore less than the difference in isentropic efficiency for the two concepts. Production of electricity is between 2% and 42% lower for the tandem arrangements in this study. Investment costs for the turbine island has been calculated for the two turbine concepts and when the costs for turbines, generator, power transmission, condensing system, piping system, buildings, assembling, commissioning and engineering has been added the sum is about the same for the two concepts. For the bio-fuelled plant with thermal capacity of 15 MW{sub th} the turbine island amount to about 10-12 MSEK and about 13-15 MSEK for the waste fired plant with a thermal capacity of 20 MW

High performance and thermally stable tandem solar selective absorber coating for concentrated solar thermal power (CSP) application

Science.gov (United States)

Prasad, M. Shiva; Kumar, K. K. Phani; Atchuta, S. R.; Sobha, B.; Sakthivel, S.

2018-05-01

A novel tandem absorber system (Mn-Cu-Co-Ox-ZrO2/SiO2) developed on an austenitic stainless steel (SS-304) substrate to show an excellent optical performance (αsol: 0.96; ɛ: 0.23@500 °C). In order to achieve this durable tandem, we experimented with two antireflective layers such as ZrO2-SiO2 and nano SiO2 layer on top of Mn-Cu-Co-Ox-ZrO2 layer. We optimized the thickness of antireflective layers to get good tandem system in terms of solar absorptance and emittance. Field emission scanning electron microscopy (FESEM), UV-Vis-NIR and Fourier transform infrared spectroscopy (FTIR) were used to characterize the developed coatings. Finally, the Mn-Cu-Co-Ox-ZrO2/SiO2 exhibits high temperature resistance up to 800 °C, thus allow an increase in the operating temperature of CSP which may lead to high efficiency. We successfully developed a high temperature resistant tandem layer with easy manufacturability at low cost which is an attractive candidate for concentrated solar power generation (CSP).

Seroprevalence and risk factors associated with Ehrlichia canis, Anaplasma spp., Borrelia burgdorferi sensu lato, and D. immitis in hunting dogs from southern Italy.

Science.gov (United States)

Piantedosi, Diego; Neola, Benedetto; D'Alessio, Nicola; Di Prisco, Francesca; Santoro, Mario; Pacifico, Laura; Sgroi, Giovanni; Auletta, Luigi; Buch, Jesse; Chandrashekar, Ramaswamy; Breitschwerdt, Edward B; Veneziano, Vincenzo

2017-10-01

Canine vector-borne diseases (CVBDs) are caused by a range of pathogens transmitted to dogs by arthropods. The present study investigates Ehrlichia canis, Anaplasma spp., Borrelia burgdorferi sensu lato, and Dirofilaria immitis seroprevalences in hunting dogs from southern Italy. Dogs (no. 1335) were tested using a commercial in-clinic enzyme-linked immunosorbent assay kit. Odds ratios (ORs) were calculated by logistic regression analysis to identify risk factors. Overall, 138/1335 dogs (10.3%) were seroreactive to at least one CVBD pathogen. E. canis, Anaplasma spp., B. burgdorferi s.l., and D. immitis seroprevalences were 7.6, 4.4, 0.3, and 0.2%, respectively. E. canis and Anaplasma spp. co-exposures were found in 30 dogs (2.2%), compared with Anaplasma spp. and B. burgdorferi s.l. co-exposures in 2 dogs (0.1%). Adult age was a risk factor for E. canis (OR 2.35) seroreactivity whereas hunting fur-bearing animals for E. canis (OR 4.75) and Anaplasma spp. (OR 1.87), respectively. The historical presence of tick infestation was identified as a risk factor for positivity to E. canis (OR 2.08) and Anaplasma spp. (OR 2.15). Finally, larger dog pack size was significantly associated with E. canis (OR 1.85) and Anaplasma spp. (OR 2.42) exposures. The results of the present survey indicated that hunting dog populations are at relative risk of CVBDs in southern Italy. Further studies are needed to evaluate the role of hunting dogs in the epidemiology of vector-borne organisms due to sharing common environments with wild, sympatric animal populations.

Impact of 'optimized' treatment planning for tandem and ring, and tandem and ovoids, using high dose rate brachytherapy for cervical cancer

International Nuclear Information System (INIS)

Noyes, William R.; Peters, Nancy E.; Thomadsen, Bruce R.; Fowler, Jack F.; Buchler, Dolores A.; Stitt, Judith A.; Kinsella, Timothy J.

1995-01-01

Purpose: Different treatment techniques are used in high dose rate (HDR) remote afterloading intracavitary brachytherapy for uterine cervical cancer. We have investigated the differences between 'optimized' and 'nonoptimized' therapy using both a tandem and ring (T/R) applicator, and a tandem and ovoids (T/O), applicator. Methods and Materials: HDR afterloading brachytherapy using the Madison System for Stage IB cervical cancer was simulated for 10 different patients using both a T/R applicator and a T/O applicator. A treatment course consists of external beam irradiation and five insertions of HDR afterloading brachytherapy. Full dosimetry calculations were performed at the initial insertion for both applicators and used as a reference for the following four insertions of the appropriate applicator. Forty dosimetry calculations were performed to determine the dose delivered to Point M (similar to Point A), Point E (obturator lymph nodes), vaginal surface, bladder, and rectum. 'Optimized' doses were specified to Point M and to the vaginal surface. 'Nonoptimized' doses were specified to Point M only. Using the linear-quadratic equation, calculations have been performed to convert the delivered dose using HDR to the biologically equivalent doses at the conventional low dose rate (LDR) at 0.60 Gy/h. Results: Major differences between 'optimized' and 'nonoptimized' LDR equivalent doses were found at the vaginal surface, bladder, and rectum. Overdoses at the vaginal surface, bladder, and rectum were calculated to be 208%, nil, and 42%, respectively, for the T/R applicator with 'nonoptimization'. However, for the T/O applicator, the overdoses were smaller, being nil, 32%, and 27%, respectively, with 'nonoptimization'. Conclusion: Doses given in high dose rate intracavitary brachytherapy border on tissue tolerance. 'Optimization' of either applicator decreases the risk of a dose that may have potential for complications. Optimization of a tandem and ovoids best ensures

A tandem queue with delayed server release

OpenAIRE

Nawijn, W.M.

1997-01-01

We consider a tandem queue with two stations. The rst station is an s-server queue with Poisson arrivals and exponential service times. After terminating his service in the rst station, a customer enters the second station to require service at an exponential single server, while in the meantime he is blocking his server in station 1 until he completes service in station 2, whereupon the server in station 1 is released. An analysis of the generating function of the simultaneous probability di...

DB2: a probabilistic approach for accurate detection of tandem duplication breakpoints using paired-end reads.

Science.gov (United States)

Yavaş, Gökhan; Koyutürk, Mehmet; Gould, Meetha P; McMahon, Sarah; LaFramboise, Thomas

2014-03-05

With the advent of paired-end high throughput sequencing, it is now possible to identify various types of structural variation on a genome-wide scale. Although many methods have been proposed for structural variation detection, most do not provide precise boundaries for identified variants. In this paper, we propose a new method, Distribution Based detection of Duplication Boundaries (DB2), for accurate detection of tandem duplication breakpoints, an important class of structural variation, with high precision and recall. Our computational experiments on simulated data show that DB2 outperforms state-of-the-art methods in terms of finding breakpoints of tandem duplications, with a higher positive predictive value (precision) in calling the duplications' presence. In particular, DB2's prediction of tandem duplications is correct 99% of the time even for very noisy data, while narrowing down the space of possible breakpoints within a margin of 15 to 20 bps on the average. Most of the existing methods provide boundaries in ranges that extend to hundreds of bases with lower precision values. Our method is also highly robust to varying properties of the sequencing library and to the sizes of the tandem duplications, as shown by its stable precision, recall and mean boundary mismatch performance. We demonstrate our method's efficacy using both simulated paired-end reads, and those generated from a melanoma sample and two ovarian cancer samples. Newly discovered tandem duplications are validated using PCR and Sanger sequencing. Our method, DB2, uses discordantly aligned reads, taking into account the distribution of fragment length to predict tandem duplications along with their breakpoints on a donor genome. The proposed method fine tunes the breakpoint calls by applying a novel probabilistic framework that incorporates the empirical fragment length distribution to score each feasible breakpoint. DB2 is implemented in Java programming language and is freely available

Tandem repeat regions within the Burkholderia pseudomallei genome and their application for high resolution genotyping

Directory of Open Access Journals (Sweden)

Harvey Steven P

2007-03-01

Full Text Available Abstract Background The facultative, intracellular bacterium Burkholderia pseudomallei is the causative agent of melioidosis, a serious infectious disease of humans and animals. We identified and categorized tandem repeat arrays and their distribution throughout the genome of B. pseudomallei strain K96243 in order to develop a genetic typing method for B. pseudomallei. We then screened 104 of the potentially polymorphic loci across a diverse panel of 31 isolates including B. pseudomallei, B. mallei and B. thailandensis in order to identify loci with varying degrees of polymorphism. A subset of these tandem repeat arrays were subsequently developed into a multiple-locus VNTR analysis to examine 66 B. pseudomallei and 21 B. mallei isolates from around the world, as well as 95 lineages from a serial transfer experiment encompassing ~18,000 generations. Results B. pseudomallei contains a preponderance of tandem repeat loci throughout its genome, many of which are duplicated elsewhere in the genome. The majority of these loci are composed of repeat motif lengths of 6 to 9 bp with 4 to 10 repeat units and are predominately located in intergenic regions of the genome. Across geographically diverse B. pseudomallei and B.mallei isolates, the 32 VNTR loci displayed between 7 and 28 alleles, with Nei's diversity values ranging from 0.47 and 0.94. Mutation rates for these loci are comparable (>10-5 per locus per generation to that of the most diverse tandemly repeated regions found in other less diverse bacteria. Conclusion The frequency, location and duplicate nature of tandemly repeated regions within the B. pseudomallei genome indicate that these tandem repeat regions may play a role in generating and maintaining adaptive genomic variation. Multiple-locus VNTR analysis revealed extensive diversity within the global isolate set containing B. pseudomallei and B. mallei, and it detected genotypic differences within clonal lineages of both species that were

Efficiency enhancement of tandem organic light-emitting devices by a combined charge generation layer and organic n-type bis(ethylenedithio)-tetrathiafulvalene-doped electron transport layer

Energy Technology Data Exchange (ETDEWEB)

Cho, Jin Taek; Kim, Dae Hun; Koh, Eun Im; Kim, Tae Whan

2014-11-03

While the operating voltage of the tandem organic light-emitting devices (OLEDs) with both an organic p-type 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile charge generation layer and a bis(ethylenedithio)-tetrathiafulvalene (BEDT-TTF)-doped 1,3,5-tris(N-phenylbenzimiazole-2-yl)benzene (TPBi) electron transport layer (ETL) was 1.3 V lower than that of the tandem OLEDs with a BEDT-TTF-undoped TPBi ETL. Luminance efficiency of the tandem OLEDs with a BEDT-TTF-doped TPBi ETL was 3.6 cd/A higher than that of the typical OLEDs. The increase in the luminance efficiency and the decrease in the operating voltage of the tandem OLEDs were attributed to improved electron injection due to the insertion of the BEDT-TTF-doped TPBi ETL. - Highlights: • Tandem organic light-emitting diodes (OLED) were fabricated. • OLED fabricated with an n-type bis(ethylenedithio)-tetrathiafulvalene. • Operating voltage of the tandem OLED was decreased from 19.8 to 18.5 V. • Luminance efficiency of the tandem OLED was increased from 31.8 to 35.4 cd/A. • Enhancement of the luminance efficiency in the tandem OLED was achieved.

Efficiency enhancement of tandem organic light-emitting devices by a combined charge generation layer and organic n-type bis(ethylenedithio)-tetrathiafulvalene-doped electron transport layer

International Nuclear Information System (INIS)

Cho, Jin Taek; Kim, Dae Hun; Koh, Eun Im; Kim, Tae Whan

2014-01-01

While the operating voltage of the tandem organic light-emitting devices (OLEDs) with both an organic p-type 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile charge generation layer and a bis(ethylenedithio)-tetrathiafulvalene (BEDT-TTF)-doped 1,3,5-tris(N-phenylbenzimiazole-2-yl)benzene (TPBi) electron transport layer (ETL) was 1.3 V lower than that of the tandem OLEDs with a BEDT-TTF-undoped TPBi ETL. Luminance efficiency of the tandem OLEDs with a BEDT-TTF-doped TPBi ETL was 3.6 cd/A higher than that of the typical OLEDs. The increase in the luminance efficiency and the decrease in the operating voltage of the tandem OLEDs were attributed to improved electron injection due to the insertion of the BEDT-TTF-doped TPBi ETL. - Highlights: • Tandem organic light-emitting diodes (OLED) were fabricated. • OLED fabricated with an n-type bis(ethylenedithio)-tetrathiafulvalene. • Operating voltage of the tandem OLED was decreased from 19.8 to 18.5 V. • Luminance efficiency of the tandem OLED was increased from 31.8 to 35.4 cd/A. • Enhancement of the luminance efficiency in the tandem OLED was achieved

Unexpected formation of 2,1-benzisothiazol-3-ones from oxathiolano ketenimines: a rare tandem process.

Science.gov (United States)

Alajarin, Mateo; Bonillo, Baltasar; Sanchez-Andrada, Pilar; Vidal, Angel; Bautista, Delia

2009-03-19

A rare one-pot reaction, a tandem [1,5]-H shift/1,5 electrocyclization/[3 + 2] cycloreversion process, leading from N-[2-(1,3-oxathiolan-2-yl)]phenyl ketenimines to 1-(beta-styryl)-2,1-benzisothiazol-3-ones and ethylene, is disclosed and mechanistically unraveled by means of a computational DFT study. The two latter stages of the tandem process are calculated to occur in a single mechanistic step via a transition structure of pseudopericyclic characteristics.

Tandem organic light-emitting diodes with buffer-modified C60/pentacene as charge generation layer

Science.gov (United States)

Wang, Zhen; Zheng, Xin; Liu, Fei; Wang, Pei; Gan, Lin; Wang, Jing-jing

2017-09-01

Buffer-modified C60/pentacene as charge generation layer (CGL) is investigated to achieve effective performance of charge generation. Undoped green electroluminescent tandem organic light-emitting diodes (OLEDs) with multiple identical emissive units and using buffer-modified C60/pentacene organic semiconductor heterojunction (OHJ) as CGL are demonstrated to exhibit better current density and brightness, compared with conventional single-unit devices. The current density and brightness both can be significantly improved with increasing the thickness of Al. However, excessive thickness of Al seriously decreases the transmittance of films and damages the interface. As a result, the maximum current efficiency of 1.43 cd·A-1 at 30 mA·cm-2 can be achieved for tandem OLEDs with optimal thickness of Al. These results clearly demonstrate that Cs2CO3/Al is an effective buffer for C60/pentacene-based tandem OLEDs.

Randomized Trial of Oral Misoprostol Treatment for Cervical Ripening Before Tandem Application in Cervix Cancer

International Nuclear Information System (INIS)

Cepni, Kimia; Gul, Sule; Cepni, Ismail; Gueralp, Onur; Sal, Veysel; Mayadagli, Alpaslan

2011-01-01

Purpose: To investigate the efficacy of oral misoprostol administered to facilitate tandem application to the cervix as a part of brachytherapy in patients with cervical cancer. Methods and Materials: Eighty patients with cervical cancer who had been planned to undergo brachytherapy at Dr. Luetfi Kirdar Kartal Training and Research Hospital were evaluated in a double-blind, prospective, randomized trial. Patients were divided randomly into two groups of 40 patients. The first and second groups received 400 μg of misoprostol orally and placebo, respectively, 3 h before tandem application. The two groups were compared in terms of age, diameter of tumor, parity, age at first intercourse, amount of bleeding and pain at first tandem application, length of endometrial cavity measured by hysterometer, and size of Hegar dilators used for cervical dilatation. Results: Of all cases, 63.6%, 16.3%, 10%, 6.3%, 2.5%, and 1.3% were Stage IIB, IIIB, IIIA, IVA, IIA and IIC, respectively. Mean (±SD) age (range) was 49.3 ± 13.1 (25-83) years and 56.6 ± 13.2 (30-78) years in the study and control groups, respectively (p = 0.015). Age at first intercourse, diameter of tumor, parity, amount of bleeding at first tandem application, and length of endometrial cavity measured by hysterometer were not significantly different between the two groups. Pain score was significantly higher in the control group (p < 0.001). Application was significantly easier in the study group compared with controls (p < 0.001). Average size of initial Hegar dilators used for cervical dilatation was significantly higher in the study group compared with controls (p = 0.017). Conclusion: Administration of misoprostol 400 μg orally for cervical ripening before tandem application facilitates the procedure, increases patient tolerability and comfort, and may decrease complication rates.

Genetic Analysis of Eight X-Chromosomal Short Tandem Repeat ...

African Journals Online (AJOL)

X-Chromosome short tandem repeat (STR) typing can complement existing DNA profiling protocols and can also offer useful information in cases of complex kinship analysis. This is the first population study of 8 X-linked STRs in Iraq. The purpose of this work was to provide a basic data of allele and haplotype frequency for ...

Ultimate performance of polymer: Fullerene bulk heterojunction tandem solar cells

NARCIS (Netherlands)

Kotlarski, J.D.; Blom, P.W.M.

2011-01-01

We present the model calculations to explore the potential of polymer:fullerene tandem solar cells. As an approach we use a combined optical and electrical device model, where the absorption profiles are used as starting point for the numerical current-voltage calculations. With this model a maximum

Semi-transparent perovskite solar cells for tandems with silicon and CIGS

KAUST Repository

Bailie, Colin D.; Christoforo, M. Greyson; Mailoa, Jonathan P.; Bowring, Andrea R.; Unger, Eva L.; Nguyen, William H.; Burschka, Julian; Pellet, Norman; Lee, Jungwoo Z.; Grä tzel, Michael; Noufi, Rommel; Buonassisi, Tonio; Salleo, Alberto; McGehee, Michael D.

2015-01-01

solar cell. We use a transparent silver nanowire electrode on perovskite solar cells to achieve a semi-transparent device. We place the semi-transparent cell in a mechanically-stacked tandem configuration onto copper indium gallium diselenide (CIGS

Aligned energy-level design for decreasing operation voltage of tandem white organic light-emitting diodes

International Nuclear Information System (INIS)

Chang, Chih-Hao; Wu, Zih-Jyun; Liang, Yi-Hu; Chang, Yu-Shuo; Chiu, Chuan-Hao; Tai, Cheng-Wei; Chang, Hsin-Hua

2013-01-01

In general, organic light-emitting devices (OLEDs) need to operate at higher current density levels to ensure an ample light flux. However, stressed operation will result in poor performance and limited device lifetime. Recently, a tandem structure has been proposed as a pivotal technique to meet the stringent lighting requirements for OLED commercialization, with a research focus on decreasing the concomitant higher operation voltage. Driving two connected emission units (EMUs) in a tandem structure often requires more than twice the driving voltage for a single EMU. This study investigates bipolar host materials and their effective employment in fabricating tandem white phosphorescent OLEDs (PhOLEDs). In addition, the design of a mechanism to align the energy level between the hole transport layer/emitting layer is shown to effectively mitigate operational voltages. In sharp contrast to devices using a unipolar host material, we demonstrate that the turn-on voltage of blue PhOLEDs could be decreased from 3.8 V to 2.7 V through utilizing a bipolar host. Furthermore, applying the proposed techniques to tandem white PhOLEDs produces a luminance of 10 3 cd/m 2 by a 10.1 V driving voltage. - Highlights: • The matched energy level between the hole transport/emitting layer lowers voltages. • Multiple conduction dopants were used to investigate charge generation layer. • Two-color emitters were used to quantify the charge generation strength

Medium area, flexible single and tandem junction solar cells based on roll coated semi-random copolymers

DEFF Research Database (Denmark)

Andersen, Thomas Rieks; Dam, Henrik Friis; Burkhart, Beate

2014-01-01

laboratory roll-coater using only slot-die coating and flexographic printing under ambient conditions on a flexible ITO-free substrate. In order to overcome a low JSC and FF obtained for single junction devices, devices were also prepared in a tandem geometry making it possible to employ thinner junction...... films. Power conversion efficiencies of up to 1.36% and 1.31% were achieved for the tandem and single junction geometries, respectively....

Homo-Tandem Polymer Solar Cells withVOC>1.8 V for Efficient PV-Driven Water Splitting

KAUST Repository

Gao, Yangqin

2016-03-06

Efficient homo-tandem and triple-junction polymer solar cells are constructed by stacking identical subcells composed of the wide-bandgap polymer PBDTTPD, achieving power conversion efficiencies >8% paralleled by open-circuit voltages >1.8 V. The high-voltage homo-tandem is used to demonstrate PV-driven electrochemical water splitting with an estimated solar-to-hydrogen conversion efficiency of ≈6%. © 2016 WILEY-VCH Verlag GmbH & Co.

A tandem cross-metathesis/semipinacol rearrangement reaction.

Science.gov (United States)

Plummer, Christopher W; Soheili, Arash; Leighton, James L

2012-05-18

An efficient and (E)-selective synthesis of a 6-alkylidenebicyclo[3.2.1]octan-8-one has been developed. The key step is a tandem cross-metathesis/semipinacol rearrangement reaction, wherein the Hoveyda-Grubbs II catalyst, or more likely a derivative thereof, serves as the Lewis acid for the rearrangement. Despite the fact that both the starting alkene and the cross-metathesis product are viable rearrangement substrates, only the latter rearranges, suggesting that the Lewis acidic species is generated only after the cross-metathesis reaction is complete.

Some new ideas for Tandem Mirror blankets

International Nuclear Information System (INIS)

Neef, W.S. Jr.

1981-01-01

The Tandem Mirror Reactor, with its cylindrical central cell, has led to numerous blanket designs taking advantage of the simple geometry. Also many new applications for fusion neutrons are now being considered. To the pure fusion electricity producers and hybrids producing fissile fuel, we are adding studies of synthetic fuel producers and fission-suppressed hybrids. The three blanket concepts presented are new ideas and should be considered illustrative of the breadth of Livermore's application studies. They are not meant to imply fully analyzed designs

Flying Posture of Tandem Warhead Influences its Penetrating and Following Performance

Directory of Open Access Journals (Sweden)

Jin-tao Wang

2014-02-01

Full Text Available In this study, we investigated a novel monolithic tandem penetrating-blast warhead, which can destroy targets with adjustable parameters including attack velocity, angles, as well as yaw angles. Different flying postures determine different performance of the precursory EFP in penetration process and its following projectile in secondary process. In order to characterize the influence of flying posture, we established a finite elements analysis model. This model has been verified by a static experiment. Our results indicated that the attack velocity of the warhead has tiny influence of the penetration process. However, larger attack angle of the warhead will lead to bad performance of the warhead. Meanwhile, yaw angle range should be controlled in small values due to its randomness. The comprehensive properties of the tandem warhead meet the design requirement, and it is able to damage the target effectively.

Present status of tandem accelerator in Tsukuba University

Energy Technology Data Exchange (ETDEWEB)

Ishihara, Toyoyuki; Oshima, Hiroyuki; Ishii, Satoshi [Tsukuba Univ., Ibaraki (Japan). Tandem Accelerator Center; and others

1996-12-01

The tandem accelerator in Tsukuba University, 12UD Peletron, has continued the operation for 21 years, and the total operation time became 61,822 hours as of the end of March, 1996. In this paper, the state of operation of the tandem accelerator in 1995 and the state of use classified by experimental fields are reported. As for the improvement of peripheral equipment, the renewal of the radiation monitoring system and the new installation of the going-in and out control system for radiation control zones were carried out. In fiscal year 1995, the operation time of the accelerator was 3,966 hours, and ion acceleration time was 3,427 hours or 86%. The renewal and improvement of the accelerator system that had been begun in fiscal year 1989 was completed. Also the operation at highest accelerating voltage 12 MV was carried out for 7 hours. In March, the operation was not done because of the periodic inspection. The state of use of two ion sources for joint utilization is shown, and 20 kinds of ions were used. The state of joint utilization, the troubles and repair, and the renewal and new installation are reported. The plan of installing 1 MV TANDETRON is explained. (K.I.)

Plasma confinement in the GAMMA 10 tandem mirror

International Nuclear Information System (INIS)

Yatsu, K.; Bruskin, L.G.; Cho, T.

1999-01-01

The central-cell density and the diamagnetic signal were doubled due to plug potential formation by ECRH in the hot ion mode experiments on the GAMMA 10 tandem mirror. In order to obtain these remarkable results, the axisymmetrized heating patterns of ECRH and ICRF were optimized. Furthermore, conducting plates were installed adjacent to the surface of the plasma along the flat shaped magnetic flux tube located at the anchor transition regions; the plates may contribute to reduce some irregular electric fields produced possibly with ECRH in these thin flux tube regions. The conducting plates contributed to the reduction of the radial loss rate to be less than 3% of the total particle losses along with the improvements in the reproducibility of the experiments and the controllability of the potential confinement. The increases in the central-cell density and the diamagnetism in association with the increase in the plug potentials scaled well with increasing the ECRH powers. A plug potential of 0.6 kV and a density increase of 100% were achieved using an ECRH power of 140 kW injected into both plug regions. The plasma confinement was improved by an order of magnitude over a simple mirror confinement due to the tandem mirror potential formation. (author)

JAEA-Tokai tandem annual report 2010. April 1, 2010 - March 31, 2011

International Nuclear Information System (INIS)

Matsuda, Makoto; Takeuchi, Suehiro

2011-12-01

The JAEA-Tokai tandem accelerator complex has been used in various research fields such as nuclear science and material science by researchers not only of JAEA but also from universities, research institutes and industrial companies. This annual report covers developments of accelerators and research activities carried out using the tandem accelerator, superconducting booster, and radioactive nuclear beam accelerator, from April 1, 2010 to March 31, 2011. Thirty-six summary reports were categorized into seven research/development fields: (1) accelerator operation and development, (2) nuclear structure, (3) nuclear reaction, (4) nuclear chemistry, (5) nuclear theory, (6) atomic physics and solid state physics, (7) radiation effects in materials. This report also lists publications, meetings, personnel, committee members, cooperative researches and common use programs. (author)

JAEA-Tokai tandem annual report 2013. April 1, 2013 - March 31, 2014

International Nuclear Information System (INIS)

Osa, Akihiko; Nishio, Katsuhisa; Tsukada, Kazuaki; Ishikawa, Norito; Toh, Yosuke; Koura, Hiroyuki; Ohkubo, Nariaki; Matsuda, Makoto

2016-12-01

The Japan Atomic Energy Agency (JAEA)-Tokai tandem accelerator complex has been used in various research fields such as nuclear science and material science by researchers not only of JAEA but also from universities, research institutes and industrial companies. This annual report covers developments of accelerators and research activities carried out using the tandem accelerator and superconducting booster from April 1, 2013 to March 31, 2014. Thirty-one summary reports were categorized into seven research/development fields: (1) accelerator operation, (2) nuclear structure, (3) nuclear reaction, (4) nuclear chemistry, (5) nuclear theory, (6) atomic physics and solid state physics, (7) radiation effects in materials. This report also lists publications, meetings, personnel, committee members, cooperative researches and common use programs. (author)

JAEA-Tokai tandem annual report 2010. April 1, 2010 - March 31, 2011

Energy Technology Data Exchange (ETDEWEB)

Matsuda, Makoto; Takeuchi, Suehiro [Japan Atomic Energy Agency, Nuclear Science Research Institute, Tokai, Ibaraki (Japan); Chiba, Satoshi; Mitsuoka, Shin-ichi; Tsukada, Kazuaki [Japan Atomic Energy Agency, Advanced Science Research Center, Tokai, Ibaraki (Japan); Ishikawa, Norito; Toh, Yosuke [Japan Atomic Energy Agency, Nuclear Science and Engineering Directorate, Tokai, Ibaraki (Japan)

2011-12-15

The JAEA-Tokai tandem accelerator complex has been used in various research fields such as nuclear science and material science by researchers not only of JAEA but also from universities, research institutes and industrial companies. This annual report covers developments of accelerators and research activities carried out using the tandem accelerator, superconducting booster, and radioactive nuclear beam accelerator, from April 1, 2010 to March 31, 2011. Thirty-six summary reports were categorized into seven research/development fields: (1) accelerator operation and development, (2) nuclear structure, (3) nuclear reaction, (4) nuclear chemistry, (5) nuclear theory, (6) atomic physics and solid state physics, (7) radiation effects in materials. This report also lists publications, meetings, personnel, committee members, cooperative researches and common use programs. (author)

JAEA-Tokai tandem annual report 2011. April 1, 2011 - March 31, 2012

International Nuclear Information System (INIS)

Nishio, Katsuhisa; Tsukada, Kazuaki; Koura, Hiroyuki

2014-04-01

The JAEA-Tokai tandem accelerator complex has been used in various research fields such as nuclear science and material science by researchers not only of JAEA but also from universities, research institutes and industrial companies. This annual report covers developments of accelerators and research activities carried out using the tandem accelerator, superconducting booster, and radioactive nuclear beam accelerator, from April 1, 2011 to March 31, 2012. Twenty-seven summary reports were categorized into seven research/development fields: (1) accelerator operation and development, (2) nuclear structure, (3) nuclear reaction, (4) nuclear chemistry, (5) nuclear theory, (6) atomic physics and solid state physics, (7) radiation effects in materials. This report also lists publications, meetings, personnel, committee members, cooperative researches and common use programs. (author)

Liquid chromatographic-tandem mass spectrometric determination of selected sulphonamides in milk

NARCIS (Netherlands)

Rhijn, van J.A.; Lasaroms, J.J.P.; Berendsen, B.J.A.; Brinkman, U.A.Th.

2002-01-01

Liquid chromatography–tandem mass spectrometry is used for the quantitative analysis of selected sulphonamides in milk. Ultrafiltration is the only sample pre-treatment technique which is required. Consequently, sample throughput is much higher than with conventional procedures, and analyte

Amorphous and microcrystalline silicon applied in very thin tandem solar cells

Energy Technology Data Exchange (ETDEWEB)

Schicho, Sandra

2011-07-28

Thin-film solar cells are fabricated by low-cost production processes, and are therefore an alternative to conventionally used wafer solar cells based on crystalline silicon. Due to the different band gaps, tandem cells that consist of amorphous (a-Si:H) and microcrystalline ({mu}c-Si:H) single junction solar cells deposited on top of each other use the solar spectrum much more efficient than single junction solar cells. The silicon layers are usually deposited on TCO (Transparent Conductive Oxide)-coated glass and metal- or plastic foils. Compared to the CdTe and CIGS based thin-film technologies, silicon thin-film solar cells have the advantage that no limitation of raw material supply is expected and no toxic elements are used. Nevertheless, the production cost per Wattpeak is the decisive factor concerning competitiveness and can be reduced by, e.g., shorter deposition times or reduced material consumption. Both cost-reducing conceptions are simultaneously achieved by reducing the a-Si:H and {mu}c-Si:H absorber layer thicknesses in a tandem device. In the work on hand, the influence of an absorber layer thickness reduction up to 77% on the photovoltaic parameters of a-Si:H/{mu}c-Si:H tandem solar cells was investigated. An industry-oriented Radio Frequency Plasma-Enhanced Chemical Vapour Deposition (RF-PECVD) system was used to deposit the solar cells on glass substrates coated with randomly structured TCO layers. The thicknesses of top and bottom cell absorber layers were varied by adjusting the deposition time. Reduced layer thicknesses lead to lower absorption and, hence, to reduced short-circuit current densities which, however, are partially balanced by higher open-circuit voltages and fill factors. Furthermore, by using very thin amorphous top cells, the light-induced degradation decreases tremendously. Accordingly, a thickness reduction of 75% led to an efficiency loss of only 21 %. By adjusting the parameters for the deposition of a-Si:H top cells, a

Therapeutic plasma exchange performed in tandem with hemodialysis without supplemental calcium in the apheresis circuit.

Science.gov (United States)

Zhao, Yong; Ibrahim, Hiba; Bailey, Jeffrey A; Linden, Jeanne; Hickson, Elda; Haynes, Stefanie; Greene, Mindy; Vauthrin, Michelle; Weinstein, Robert

2017-06-01

Therapeutic plasma exchange (TPE) and hemopoietic progenitor cell (HPC) collection are apheresis procedures that can safely be performed in tandem with hemodialysis. Despite the return of citrate-anticoagulated blood to the patient during HPC collection, it is not necessary to administer supplemental calcium during these procedures because the ionized calcium concentration is restored as the returning blood passes through the dialyzer. It is not known whether this applies to TPE, in which a mixture of blood and pharmaceutical albumin, an avid binder of plasma ionized calcium, is returned to the patient through the dialyzer. We report on three dialysis-dependent patients who required TPE and underwent tandem treatments without supplemental calcium in the apheresis circuit. Overall, ionized calcium fell 4-12% (P = 0.0.024) and patients reported no symptoms of hypocalcemic toxicity. Tandem hemodialysis/TPE can be performed without supplemental calcium in the apheresis circuit. J. Clin. Apheresis 32:154-157, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The Friction of Vehicle Brake Tandem Master Cylinder

International Nuclear Information System (INIS)

Kao, M J; Chang, H; Tsung, T T; Lin, H M

2006-01-01

The behaviour of an elastomeric seal for vehicle brake Tandem master cylinder is measured and analyzed in temperature and brake fluids changed. Working conditions are simulated for different piston rod velocity and cylinder supply pressure, in temperature rising, brakefluid boundary and Nanoaluminum oxide brakefluid oxide brakefluid lubrication. The result shows that Nanoaluminum oxide brakefluid with its ball shape can highly reduce friction coefficient to avoid seal excessive wear and reduce slick slip in brake applications

Tandem neopentyl glycol maltosides (TNMs) for membrane protein stabilisation†

OpenAIRE

Bae, Hyoung Eun; Mortensen, Jonas S.; Ribeiro, Orquidea; Du, Yang; Ehsan, Muhammad; Kobilka, Brian K.; Loland, Claus J.; Byrne, Bernadette; Chae, Pil Seok

2016-01-01

A novel class of detergents, designated tandem neopentyl glycol maltosides (TNMs), were evaluated with four target membrane proteins. The best detergent varied depending on the target, but TNM-C12L and TNM-C11S were notable for their ability to confer increased membrane protein stability compared to DDM. These agents have potential for use in membrane protein research.

Tandem neopentyl glycol maltosides (TNMs) for membrane protein stabilisation.

Science.gov (United States)

Bae, Hyoung Eun; Mortensen, Jonas S; Ribeiro, Orquidea; Du, Yang; Ehsan, Muhammad; Kobilka, Brian K; Loland, Claus J; Byrne, Bernadette; Chae, Pil Seok

2016-10-04

A novel class of detergents, designated tandem neopentyl glycol maltosides (TNMs), were evaluated with four target membrane proteins. The best detergent varied depending on the target, but TNM-C12L and TNM-C11S were notable for their ability to confer increased membrane protein stability compared to DDM. These agents have potential for use in membrane protein research.

Tandem neopentyl glycol maltosides (TNMs) for membrane protein stabilisation†

Science.gov (United States)

Bae, Hyoung Eun; Mortensen, Jonas S.; Ribeiro, Orquidea; Du, Yang; Ehsan, Muhammad; Kobilka, Brian K.; Loland, Claus J.; Byrne, Bernadette

2017-01-01

A novel class of detergents, designated tandem neopentyl glycol maltosides (TNMs), were evaluated with four target membrane proteins. The best detergent varied depending on the target, but TNM-C12L and TNM-C11S were notable for their ability to confer increased membrane protein stability compared to DDM. These agents have potential for use in membrane protein research. PMID:27711401

Interim report on the tandem mirror hybrid design study

International Nuclear Information System (INIS)

Moir, R.W.

1979-01-01

The initial phase of a 2-year design study of a tandem mirror fusion reactor is presented. The following chapters are included: (1) mechanical design of the plant; (2) plasma physics; (3) blanket design; (4) magnet design; (5) injector design; (6) direct convertor design; (7) balance of plant design; (8) fission burner reactor; (9) environment and safety; and (10) economic analysis

Distanzen überwinden: Über das Potenzial audio-visueller e-Tandems für den Deutschunterricht von Erwachsenen in Kolumbien

Directory of Open Access Journals (Sweden)

Yasmin El-Hariri

2015-04-01

Full Text Available Sprachenlernen im Tandem ist eine Methode, bei der zwei Lernende mit unterschiedlichen Sprachen von- und miteinander lernen. Die wachsende Verfügbarkeit elektronischer Medien ermöglicht solche Kooperationen heutzutage auch über große Distanzen (e-Tandem. Der vorliegende Beitrag präsentiert Ergebnisse einer im August/September 2014 durchgeführten Onlinebefragung unter Deutschlernenden in Kolumbien. Ziel dieser Befragung war es, Sprachlerneinstellungen von Lernenden, deren Beweggründe für die Wahl von DaF sowie Erwartungshaltungen hinsichtlich e-Tandems zu erheben. Die Ergebnisse zeigen prinzipiell ein hohes Potenzial dieser Lernform, geben jedoch auch Hinweise auf in der Planung und Durchführung besonders zu beachtende Aspekte, die für eine gelungene Umsetzung unabdingbar sind.   Tandem language learning is a method which involves two learners with different languages learning from and with each other. The growing availability of electronic media nowadays allows such co-operation across long distances (e-Tandem. The present contribution presents results of an online survey conducted in August/September 2014 among learners of German in Colombia. The aim of this survey was to determine the learners' attitudes towards language learning, their motivation to choose German as a foreign language, as well as their expectations regarding e-Tandem language learning. Results show a high potential of such a learning approach; however, they also indicate crucial aspects which have to be considered specifically during implementation in order to develop the full potential of the method.

Educational activities with a tandem accelerator

Science.gov (United States)

Casolaro, P.; Campajola, L.; Balzano, E.; D'Ambrosio, E.; Figari, R.; Vardaci, E.; La Rana, G.

2018-05-01

Selected experiments in fundamental physics have been proposed for many years at the Tandem Accelerator of the University of Napoli ‘Federico II’s Department of Physics as a part of a one-semester laboratory course for graduate students. The aim of this paper is to highlight the educational value of the experimental realization of the nuclear reaction 19F(p,α)16O. With the purpose of verifying the mass-energy equivalence principle, different aspects of both classical and modern physics can be investigated, e.g. conservation laws, atomic models, nuclear physics applications to compositional analysis, nuclear cross-section, Q-value and nuclear spectroscopic analysis.

Negative ion sources for tandem accelerator

International Nuclear Information System (INIS)

Minehara, Eisuke

1980-08-01

Four kinds of negative ion sources (direct extraction Duoplasmatron ion source, radial extraction Penniing ion source, lithium charge exchange ion source and Middleton-type sputter ion source) have been installed in the JAERI tandem accelerator. The ion sources can generate many negative ions ranging from Hydrogen to Uranium with the exception of Ne, Ar, Kr, Xe and Rn. Discussions presented in this report include mechanisms of negative ion formation, electron affinity and stability of negative ions, performance of the ion sources and materials used for negative ion production. Finally, the author will discuss difficult problems to be overcome in order to get any negative ion sufficiently. (author)

Analysis of posttranslational modifications of proteins by tandem mass spectrometry

DEFF Research Database (Denmark)

Larsen, Martin Røssel; Trelle, Morten B; Thingholm, Tine E

2006-01-01

-temporal distribution in cells and tissues. Most PTMs can be detected by protein and peptide analysis by mass spectrometry (MS), either as a mass increment or a mass deficit relative to the nascent unmodified protein. Tandem mass spectrometry (MS/MS) provides a series of analytical features that are highly useful...

JAERI tandem, linac and V.D.G. annual report 1984

International Nuclear Information System (INIS)

Shikazono, Naomoto; Iizumi, Masashi; Ishii, Mitsuhiko; Kawarasaki, Yuuki; Murayama, Michio; Okashita, Hiroshi; Ozawa, Kunio; Suto, Yoichi

1985-07-01

This annual report describes research activities which have been performed with the JAERI tandem accelerator, the electron linear accelerator and the Van de Graaff accelerator from April 1, 1984 to March 31, 1985. Summary reports of 53 papers, publications, personnel and a list of cooperative researches with universities are contained. (author)

JAERI tandem, linac and V.D.G. annual report 1987

International Nuclear Information System (INIS)

1988-10-01

This annual report describes research activities which have been performed with the JAERI tandem accelerator, the electron linear accelerator and the Van de Graaff accelerator from April 1, 1987 to March 31, 1988. Summary reports of 49 papers, and list of publications, personnel and cooperative researches with universities are contained. (author)

JAERI TANDEM, LINAC and V.D.G. annual report 1989

International Nuclear Information System (INIS)

1990-09-01

This annual report describes research activities which have been performed with the JAERI tandem accelerator, the electron linear accelerator and the Van de Graaff accelerator from April 1, 1989 to March 31, 1990. Summary reports of 49 papers, and list of publications, personnel and cooperative researches with universities are contained. (author)

JAERI Tandem, LINAC and V.D.G. annual report 1986

International Nuclear Information System (INIS)

1987-08-01

This annual report describes research activities which have been performed with the JAERI tandem accelerator, the electron linear accelerator and the Van de Graaff accelerator from April 1, 1986 to March 31, 1987. Summary reports of 55 papers, and list of publications, personnel and cooperative researches with universities are contained. (author)

JAERI tandem, LINAC and V.D.G. annual report 1988

International Nuclear Information System (INIS)

1989-09-01

This annual report describes research activities which have been performed with the JAERI tandem accelerator, the electron linear accelerator and the Van de Graaff accelerator from April 1, 1988 to March 31, 1989. Summary reports of 45 papers, and list of publications, personnel and cooperative researches with universities are contained. (author)

JAERI TANDEM, LINAC and V.D.G. annual report, 1985

International Nuclear Information System (INIS)

1986-08-01

This annual report describes research activities which have been performed with the JAERI tandem accelerator, the electron linear accelerator and the Van de Graaff accelerator from April 1, 1985 to March 31, 1986. Summary reports of 52 papers, and list of publications, personnel and cooperative researches with universities are contained. (author)

Glucose and glycerol concentrations and their tracer enrichment measurements using liquid chromatography tandem mass spectrometry

DEFF Research Database (Denmark)

Bornø, Andreas; Foged, Lene; van Hall, Gerrit

2014-01-01

The present study describes a new liquid chromatography tandem mass spectrometry method for high-throughput quantification of glucose and glycerol in human plasma using stable isotopically labeled internal standards and is suitable for simultaneous measurements of glucose and glycerol enrichments...... of variation were 2.0% and 9.7%, respectively. After derivatization, plasma samples were stable for at least 14 days. In conclusion, we have developed and validated a novel, accurate, and sensitive high-throughput liquid chromatography tandem mass spectrometry method for simultaneous determination of glucose...

Damage situation by the Great East Japan Earthquake and post-quake reconstruction project of the Tandem Accelerator Facility at the University of Tsukuba

International Nuclear Information System (INIS)

Sasa, Kimikazu

2012-01-01

The 12UD Pelletron tandem accelerator at the University of Tsukuba suffered serious damage from the Great East Japan Earthquake on 11 March 2011. On the day, the 12UD Pelletron tandem accelerator was in operation at 8 MV. The electricity supply went out during the earthquake. Fortunately, there were no causalties by the earthquake in the facility. However, all high voltage accelerating columns fell down in the accelerator tank. We decided to shut down the 12UD Pelletron tandem accelerator. At present, we have a plan to install a new middle-sized tandem accelerator instead of the broken 12UD Pelletron tandem accelerator at the 2nd target room connecting the beam line to existing facilities at the 1st target room. The construction of the new accelerator system will be completed by spring 2014. (author)

NSF tandem stack support structure deflection characteristics

International Nuclear Information System (INIS)

Cook, J.

1979-12-01

Results are reported of load tests carried out on the glass legs of the insulating stack of the 30 MV tandem Van de Graaff accelerator now under construction at Daresbury Laboratory. The tests to investigate the vulnerability of the legs when subjected to tensile stresses were designed to; establish the angle of rotation of the pads from which the stresses in the glass legs may be calculated, proof-test the structure and at the same time reveal any asymmetry in pad rotations or deflections, and to confirm the validity of the computer design analysis. (UK)

Beam trajectories through the upgraded XTU tandem

International Nuclear Information System (INIS)

Guan Xialing

1988-01-01

The paper deals with a problem applicable to all electrostatic accelerators with inclined field accelerating tubes, how the trajectory of the central beam particle is affected if one of the accelerating gaps must be shorted out due to insulator failure. For the long tube of the Legnaro XTU tandem the effect of each accelerator gap is calculated and a method of compensation either by shorting out an appropriate gap with reversed incline or by appropriately steering the beam into the entrance of the low energy tube is given. (orig.)

Plasma confinement in the TMX tandem mirror

International Nuclear Information System (INIS)

Hooper, E.B. Jr.; Allen, S.L.; Casper, T.A.

1981-01-01

Plasma confinement in the Tandem Mirror Experiment (TMX) is described. Axially confining potentials are shown to exist throughout the central 20-cm core of TMX. Axial electron-confinement time is up to 100 times that of single-cell mirror machines. Radial transport of ions is smaller than axial transport near the axis. It has two parts at large radii: nonambipolar, in rough agreement with predictions from resonant-neoclassical transport theory, and ambipolar, observed near the plasma edge under certain conditions, accompanied by a low-frequency, m = 1 instability or strong turbulence

SU-E-T-615: Investigation of the Dosimetric Impact of Tandem Loading in the Treatment of Cervical Cancer for HDR Brachytherapy Procedures

Energy Technology Data Exchange (ETDEWEB)

Esquivel, C; Patton, L; Nelson, K; Lin, B [Cancer Care Centers of South Texas, San Antonio, TX (United States)

2014-06-01

Purpose: To quantify the dosimetric impact of the tandem loading in the treatment of cervical cancer for HDR brachytherapy procedures. Methods: Ten patients were evaluated, each of whom received 5 fractions of treatment. Tandem and ovoid sets were inserted into the uterine cavity based on institutional protocols and procedures. Following insertion and stabilization, CT image sets of 1.5mm slice thickness were acquired and sent to the Oncentra V4.3 Treatment Planning System. Critical structures such as the CTV, bladder, rectum, sigmoid, and bowel were contoured and a fractional dose of 5.5Gy was prescribed to Point A for each patient. Six different treatment plans were created for each fraction using varying tandem weightings; from 0.5 to 1.4 times that of the ovoids. Surface dose evaluation of various ovoid diameters, 2.0-3.5cm, at the vaginal fornices was also investigated. Results: Critical structures were evaluated based on varying dose and volume constraints, in particular the 2.0 cc volume recommendation cited by the gynecological GEC-ESTRO working group. Based on dose volume histogram evaluation, a reduction of dose to the critical structures was most often discovered when the tandem weighting was increased. CTV coverage showed little change as the tandem weighting was varied. Ovoid surface dose decreased by 50-65% as the tandem weighting increased. Conclusion: The advantage of 3D planning with HDR brachytherapy is the dose optimization for each individual treatment plan. This investigation shows that by utilizing large tandem weightings, 1.4 times greater than the ovoid, one can still achieve adequate coverage of the CTV and relatively low doses to the critical structures. In some cases, one would still have to optimize further per individual case. In addition, the ovoid surface dose was greatly decreased when large tandem weighting was utilized; especially for small ovoid diameters.

SU-E-T-615: Investigation of the Dosimetric Impact of Tandem Loading in the Treatment of Cervical Cancer for HDR Brachytherapy Procedures

International Nuclear Information System (INIS)

Esquivel, C; Patton, L; Nelson, K; Lin, B

2014-01-01

Purpose: To quantify the dosimetric impact of the tandem loading in the treatment of cervical cancer for HDR brachytherapy procedures. Methods: Ten patients were evaluated, each of whom received 5 fractions of treatment. Tandem and ovoid sets were inserted into the uterine cavity based on institutional protocols and procedures. Following insertion and stabilization, CT image sets of 1.5mm slice thickness were acquired and sent to the Oncentra V4.3 Treatment Planning System. Critical structures such as the CTV, bladder, rectum, sigmoid, and bowel were contoured and a fractional dose of 5.5Gy was prescribed to Point A for each patient. Six different treatment plans were created for each fraction using varying tandem weightings; from 0.5 to 1.4 times that of the ovoids. Surface dose evaluation of various ovoid diameters, 2.0-3.5cm, at the vaginal fornices was also investigated. Results: Critical structures were evaluated based on varying dose and volume constraints, in particular the 2.0 cc volume recommendation cited by the gynecological GEC-ESTRO working group. Based on dose volume histogram evaluation, a reduction of dose to the critical structures was most often discovered when the tandem weighting was increased. CTV coverage showed little change as the tandem weighting was varied. Ovoid surface dose decreased by 50-65% as the tandem weighting increased. Conclusion: The advantage of 3D planning with HDR brachytherapy is the dose optimization for each individual treatment plan. This investigation shows that by utilizing large tandem weightings, 1.4 times greater than the ovoid, one can still achieve adequate coverage of the CTV and relatively low doses to the critical structures. In some cases, one would still have to optimize further per individual case. In addition, the ovoid surface dose was greatly decreased when large tandem weighting was utilized; especially for small ovoid diameters

5meCpG epigenetic marks neighboring a primate-conserved core promoter short tandem repeat indicate X-chromosome inactivation.

Science.gov (United States)

Machado, Filipe Brum; Machado, Fabricio Brum; Faria, Milena Amendro; Lovatel, Viviane Lamim; Alves da Silva, Antonio Francisco; Radic, Claudia Pamela; De Brasi, Carlos Daniel; Rios, Álvaro Fabricio Lopes; de Sousa Lopes, Susana Marina Chuva; da Silveira, Leonardo Serafim; Ruiz-Miranda, Carlos Ramon; Ramos, Ester Silveira; Medina-Acosta, Enrique

2014-01-01

X-chromosome inactivation (XCI) is the epigenetic transcriptional silencing of an X-chromosome during the early stages of embryonic development in female eutherian mammals. XCI assures monoallelic expression in each cell and compensation for dosage-sensitive X-linked genes between females (XX) and males (XY). DNA methylation at the carbon-5 position of the cytosine pyrimidine ring in the context of a CpG dinucleotide sequence (5meCpG) in promoter regions is a key epigenetic marker for transcriptional gene silencing. Using computational analysis, we revealed an extragenic tandem GAAA repeat 230-bp from the landmark CpG island of the human X-linked retinitis pigmentosa 2 RP2 promoter whose 5meCpG status correlates with XCI. We used this RP2 onshore tandem GAAA repeat to develop an allele-specific 5meCpG-based PCR assay that is highly concordant with the human androgen receptor (AR) exonic tandem CAG repeat-based standard HUMARA assay in discriminating active (Xa) from inactive (Xi) X-chromosomes. The RP2 onshore tandem GAAA repeat contains neutral features that are lacking in the AR disease-linked tandem CAG repeat, is highly polymorphic (heterozygosity rates approximately 0.8) and shows minimal variation in the Xa/Xi ratio. The combined informativeness of RP2/AR is approximately 0.97, and this assay excels at determining the 5meCpG status of alleles at the Xp (RP2) and Xq (AR) chromosome arms in a single reaction. These findings are relevant and directly translatable to nonhuman primate models of XCI in which the AR CAG-repeat is monomorphic. We conducted the RP2 onshore tandem GAAA repeat assay in the naturally occurring chimeric New World monkey marmoset (Callitrichidae) and found it to be informative. The RP2 onshore tandem GAAA repeat will facilitate studies on the variable phenotypic expression of dominant and recessive X-linked diseases, epigenetic changes in twins, the physiology of aging hematopoiesis, the pathogenesis of age-related hematopoietic

5meCpG epigenetic marks neighboring a primate-conserved core promoter short tandem repeat indicate X-chromosome inactivation.

Directory of Open Access Journals (Sweden)

Filipe Brum Machado

Full Text Available X-chromosome inactivation (XCI is the epigenetic transcriptional silencing of an X-chromosome during the early stages of embryonic development in female eutherian mammals. XCI assures monoallelic expression in each cell and compensation for dosage-sensitive X-linked genes between females (XX and males (XY. DNA methylation at the carbon-5 position of the cytosine pyrimidine ring in the context of a CpG dinucleotide sequence (5meCpG in promoter regions is a key epigenetic marker for transcriptional gene silencing. Using computational analysis, we revealed an extragenic tandem GAAA repeat 230-bp from the landmark CpG island of the human X-linked retinitis pigmentosa 2 RP2 promoter whose 5meCpG status correlates with XCI. We used this RP2 onshore tandem GAAA repeat to develop an allele-specific 5meCpG-based PCR assay that is highly concordant with the human androgen receptor (AR exonic tandem CAG repeat-based standard HUMARA assay in discriminating active (Xa from inactive (Xi X-chromosomes. The RP2 onshore tandem GAAA repeat contains neutral features that are lacking in the AR disease-linked tandem CAG repeat, is highly polymorphic (heterozygosity rates approximately 0.8 and shows minimal variation in the Xa/Xi ratio. The combined informativeness of RP2/AR is approximately 0.97, and this assay excels at determining the 5meCpG status of alleles at the Xp (RP2 and Xq (AR chromosome arms in a single reaction. These findings are relevant and directly translatable to nonhuman primate models of XCI in which the AR CAG-repeat is monomorphic. We conducted the RP2 onshore tandem GAAA repeat assay in the naturally occurring chimeric New World monkey marmoset (Callitrichidae and found it to be informative. The RP2 onshore tandem GAAA repeat will facilitate studies on the variable phenotypic expression of dominant and recessive X-linked diseases, epigenetic changes in twins, the physiology of aging hematopoiesis, the pathogenesis of age-related hematopoietic

Non-invasive prenatal detection of trisomy 21 using tandem single nucleotide polymorphisms.

Directory of Open Access Journals (Sweden)

Sujana Ghanta

Full Text Available BACKGROUND: Screening tests for Trisomy 21 (T21, also known as Down syndrome, are routinely performed for the majority of pregnant women. However, current tests rely on either evaluating non-specific markers, which lead to false negative and false positive results, or on invasive tests, which while highly accurate, are expensive and carry a risk of fetal loss. We outline a novel, rapid, highly sensitive, and targeted approach to non-invasively detect fetal T21 using maternal plasma DNA. METHODS AND FINDINGS: Highly heterozygous tandem Single Nucleotide Polymorphism (SNP sequences on chromosome 21 were analyzed using High-Fidelity PCR and Cycling Temperature Capillary Electrophoresis (CTCE. This approach was used to blindly analyze plasma DNA obtained from peripheral blood from 40 high risk pregnant women, in adherence to a Medical College of Wisconsin Institutional Review Board approved protocol. Tandem SNP sequences were informative when the mother was heterozygous and a third paternal haplotype was present, permitting a quantitative comparison between the maternally inherited haplotype and the paternally inherited haplotype to infer fetal chromosomal dosage by calculating a Haplotype Ratio (HR. 27 subjects were assessable; 13 subjects were not informative due to either low DNA yield or were not informative at the tandem SNP sequences examined. All results were confirmed by a procedure (amniocentesis/CVS or at postnatal follow-up. Twenty subjects were identified as carrying a disomy 21 fetus (with two copies of chromosome 21 and seven subjects were identified as carrying a T21 fetus. The sensitivity and the specificity of the assay was 100% when HR values lying between 3/5 and 5/3 were used as a threshold for normal subjects. CONCLUSIONS: In summary, a targeted approach, based on calculation of Haplotype Ratios from tandem SNP sequences combined with a sensitive and quantitative DNA measurement technology can be used to accurately detect fetal

Toward Male Individualization with Rapidly Mutating Y-Chromosomal Short Tandem Repeats

NARCIS (Netherlands)

K. Ballantyne (Kaye); A. Ralf (Arwin); R. Aboukhalid (Rachid); N.M. Achakzai (Niaz); T. Anjos (Tania); Q. Ayub (Qasim); J. Balažic (Jože); J. Ballantyne (Jack); D.J. Ballard (David); B. Berger (Burkhard); C. Bobillo (Cecilia); M. Bouabdellah (Mehdi); H. Burri (Helen); T. Capal (Tomas); S. Caratti (Stefano); J. Cárdenas (Jorge); F. Cartault (François); E.F. Carvalho (Elizeu); M. de Carvalho (Margarete); B. Cheng (Baowen); M.D. Coble (Michael); D. Comas (David); D. Corach (Daniel); M. D'Amato (Mauro); S. Davison (Sean); P. de Knijff (Peter); M.C.A. de Ungria (Maria Corazon); R. Decorte (Ronny); T. Dobosz (Tadeusz); B.M. Dupuy (Berit); S. Elmrghni (Samir); M. Gliwiński (Mateusz); S.C. Gomes (Sara); L. Grol (Laurens); C. Haas (Cordula); E. Hanson (Erin); J. Henke (Jürgen); L. Henke (Lotte); F. Herrera-Rodríguez (Fabiola); C.R. Hill (Carolyn); G. Holmlund (Gunilla); K. Honda (Katsuya); U.-D. Immel (Uta-Dorothee); S. Inokuchi (Shota); R. Jobling; M. Kaddura (Mahmoud); J.S. Kim (Jong); S.H. Kim (Soon); W. Kim (Wook); T.E. King (Turi); E. Klausriegler (Eva); D. Kling (Daniel); L. Kovačević (Lejla); L. Kovatsi (Leda); P. Krajewski (Paweł); S. Kravchenko (Sergey); M.H.D. Larmuseau (Maarten); E.Y. Lee (Eun Young); R. Lessig (Rüdiger); L.A. Livshits (Ludmila); D. Marjanović (Damir); M. Minarik (Marek); N. Mizuno (Natsuko); H. Moreira (Helena); N. Morling (Niels); M. Mukherjee (Meeta); P. Munier (Patrick); J. Nagaraju (Javaregowda); F. Neuhuber (Franz); S. Nie (Shengjie); P. Nilasitsataporn (Premlaphat); T. Nishi (Takeki); H.H. Oh (Hye); S. Olofsson (Sylvia); V. Onofri (Valerio); J. Palo (Jukka); H. Pamjav (Horolma); W. Parson (Walther); M. Petlach (Michal); C. Phillips (Christopher); R. Ploski (Rafal); S.P.R. Prasad (Samayamantri P.); D. Primorac (Dragan); G.A. Purnomo (Gludhug); J. Purps (Josephine); H. Rangel-Villalobos (Hector); K. Reogonekbała (Krzysztof); B. Rerkamnuaychoke (Budsaba); D.R. Gonzalez (Danel Rey); C. Robino (Carlo); L. Roewer (Lutz); A. de Rosa (Anna); A. Sajantila (Antti); A. Sala (Andrea); J.M. Salvador (Jazelyn); P. Sanz (Paula); C. Schmitt (Christian); A.K. Sharma (Anisha K.); D.A. Silva (Dayse); K.-J. Shin (Kyoung-Jin); T. Sijen (Titia); M. Sirker (Miriam); D. Siváková (Daniela); V. Škaro (Vedrana); C. Solano-Matamoros (Carlos); L. Souto (L.); V. Stenzl (Vlastimil); H. Sudoyo (Herawati); D. Syndercombe-Court (Denise); A. Tagliabracci (Adriano); D. Taylor (Duncan); A. Tillmar (Andreas); I.S. Tsybovsky (Iosif); C. Tyler-Smith (Chris); K. van der Gaag (Kristiaan); D. Vanek (Daniel); A. Völgyi (Antónia); D. Ward (Denise); P. Willemse (Patricia); E.P.H. Yap (Eric); Z-Y. Yong (Ze-Yie); I.Z. Pajnič (Irena Zupanič); M.H. Kayser (Manfred)

2014-01-01

textabstractRelevant for various areas of human genetics, Y-chromosomal short tandem repeats (Y-STRs) are commonly used for testing close paternal relationships among individuals and populations, and for male lineage identification. However, even the widely used 17-loci Yfiler set cannot resolve

Carbon nanotube foils for electron stripping in tandem accelerators

International Nuclear Information System (INIS)

Reden, Karl von; Zhang Mei; Meigs, Martha; Sichel, Enid; Fang Shaoli; Baughman, Ray H.

2007-01-01

Carbon nanotube technology has rapidly advanced in recent years, making it possible to create meter-long, ∼4 cm wide films of multi-walled tubes of less than 3 μg/cm 2 areal density in a bench top open-air procedure. The physical properties of individual carbon nanotubes have been well established, equaling or surpassing electrical and thermal conductivity and mechanical strength of most other materials, graphite in particular. The handling and transport of such nanotube films, dry-mounted self-supporting on metal frames with several cm 2 of open area, is problem-free: the aerogel films having a volumetric density of about 1.5 mg/cm 3 survived the trip by car and air from Dallas to Oak Ridge without blemish. In this paper we will present the results of first tests of these nanotube films as electron stripper media in a tandem accelerator. The tests were performed in the Model 25 URC tandem accelerator of the Holifield radioactive ion beam facility (HRIBF) at Oak Ridge National Laboratory. We will discuss the performance of nanotube films in comparison with chemical vapor deposition and laser-ablated carbon foils

Beam emittance of the Stony Brook Tandem-LINAC booster

International Nuclear Information System (INIS)

Scholldorf, A.H.

1984-01-01

This dissertation is primarily a study of the longitudinal and transverse beam emittance of the Stony Brook Heavy Ion Tandem LINAC Accelerator Facility, with a secondary emphasis on the beam dynamical design of two key elements of the system: a low energy double-drift buncher, and an achromatic double-90 0 LINAC injection system. A transverse emittance measuring system consisting of two translation stages controlled by stepper motors is described. Each stage carried a pair of beam defining slits mounted so that both horizontal and vertical emittances could be measured with only linear motion of the stage assembly. Beam currents were measured directly by a low-noise, high-sensitivity electrometer circuit integrated with the second slit-stage assembly. A mini-computer controlled the motors and acquired and displayed the data. Transverse emittance areas of beams of 12 C, 16 O, 32 S, and 58 Ni were measured at ion source extraction potential, after ion source acceleration, after tandem acceleration, and after LINAC acceleration. The results were analyzed in terms of source sputter-cone geometry, angle straggling in gas and foil strippers, and a variety of other factors

Aligned energy-level design for decreasing operation voltage of tandem white organic light-emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Chang, Chih-Hao, E-mail: chc@saturn.yzu.edu.tw [Department of Photonics Engineering, Yuan Ze University, Chung-Li 32003, Taiwan, ROC (China); Wu, Zih-Jyun; Liang, Yi-Hu; Chang, Yu-Shuo; Chiu, Chuan-Hao; Tai, Cheng-Wei [Department of Photonics Engineering, Yuan Ze University, Chung-Li 32003, Taiwan, ROC (China); Chang, Hsin-Hua, E-mail: hhua3@mail.vnu.edu.tw [Department of Electro-Optical Engineering, Vanung University, Chung-Li 32061, Taiwan, ROC (China)

2013-12-02

In general, organic light-emitting devices (OLEDs) need to operate at higher current density levels to ensure an ample light flux. However, stressed operation will result in poor performance and limited device lifetime. Recently, a tandem structure has been proposed as a pivotal technique to meet the stringent lighting requirements for OLED commercialization, with a research focus on decreasing the concomitant higher operation voltage. Driving two connected emission units (EMUs) in a tandem structure often requires more than twice the driving voltage for a single EMU. This study investigates bipolar host materials and their effective employment in fabricating tandem white phosphorescent OLEDs (PhOLEDs). In addition, the design of a mechanism to align the energy level between the hole transport layer/emitting layer is shown to effectively mitigate operational voltages. In sharp contrast to devices using a unipolar host material, we demonstrate that the turn-on voltage of blue PhOLEDs could be decreased from 3.8 V to 2.7 V through utilizing a bipolar host. Furthermore, applying the proposed techniques to tandem white PhOLEDs produces a luminance of 10{sup 3} cd/m{sup 2} by a 10.1 V driving voltage. - Highlights: • The matched energy level between the hole transport/emitting layer lowers voltages. • Multiple conduction dopants were used to investigate charge generation layer. • Two-color emitters were used to quantify the charge generation strength.

Highly Efficient Perovskite-Perovskite Tandem Solar Cells Reaching 80% of the Theoretical Limit in Photovoltage.

Science.gov (United States)

Rajagopal, Adharsh; Yang, Zhibin; Jo, Sae Byeok; Braly, Ian L; Liang, Po-Wei; Hillhouse, Hugh W; Jen, Alex K-Y

2017-09-01

Organic-inorganic hybrid perovskite multijunction solar cells have immense potential to realize power conversion efficiencies (PCEs) beyond the Shockley-Queisser limit of single-junction solar cells; however, they are limited by large nonideal photovoltage loss (V oc,loss ) in small- and large-bandgap subcells. Here, an integrated approach is utilized to improve the V oc of subcells with optimized bandgaps and fabricate perovskite-perovskite tandem solar cells with small V oc,loss . A fullerene variant, Indene-C 60 bis-adduct, is used to achieve optimized interfacial contact in a small-bandgap (≈1.2 eV) subcell, which facilitates higher quasi-Fermi level splitting, reduces nonradiative recombination, alleviates hysteresis instabilities, and improves V oc to 0.84 V. Compositional engineering of large-bandgap (≈1.8 eV) perovskite is employed to realize a subcell with a transparent top electrode and photostabilized V oc of 1.22 V. The resultant monolithic perovskite-perovskite tandem solar cell shows a high V oc of 1.98 V (approaching 80% of the theoretical limit) and a stabilized PCE of 18.5%. The significantly minimized nonideal V oc,loss is better than state-of-the-art silicon-perovskite tandem solar cells, which highlights the prospects of using perovskite-perovskite tandems for solar-energy generation. It also unlocks opportunities for solar water splitting using hybrid perovskites with solar-to-hydrogen efficiencies beyond 15%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Vivitron - A 35 MV Van de Graaff tandem. Design, performance, charge transport system

International Nuclear Information System (INIS)

Letournel, M.; Helleboid, J.M.; Bertein, H.

1985-01-01

This paper describes a new configuration for an electrostatic tandem accelerator. The project of the Strasbourg Nuclear Center is a 35 MV Van de Graaff tandem, in fact a new design in that field. The general features of the machine and its associated electrostatic field are described. The machine is designed to minimise energy dissipation within the accelerator column in the event of electrical breakdown. This is discussed as also insulator and conductor designs. Charge transport system is a particular field. The choice of a belt system and its design result from specific studies carried out at the C.R.N. with reference to the electrostatics of solid and gaseous insulations [fr

Chicken microsatellite markers isolated from libraries enriched for simple tandem repeats.

Science.gov (United States)

Gibbs, M; Dawson, D A; McCamley, C; Wardle, A F; Armour, J A; Burke, T

1997-12-01

The total number of microsatellite loci is considered to be at least 10-fold lower in avian species than in mammalian species. Therefore, efficient large-scale cloning of chicken microsatellites, as required for the construction of a high-resolution linkage map, is facilitated by the construction of libraries using an enrichment strategy. In this study, a plasmid library enriched for tandem repeats was constructed from chicken genomic DNA by hybridization selection. Using this technique the proportion of recombinant clones that cross-hybridized to probes containing simple tandem repeats was raised to 16%, compared with < 0.1% in a non-enriched library. Primers were designed from 121 different sequences. Polymerase chain reaction (PCR) analysis of two chicken reference pedigrees enabled 72 loci to be localized within the collaborative chicken genetic map, and at least 30 of the remaining loci have been shown to be informative in these or other crosses.

X-Chromosomal short tandem repeat loci in the Turkish population ...

African Journals Online (AJOL)

In this study, we aimed to demonstrate the importance and utility of polymorphic short tandem repeat (STR) found on the human X chromosome and to provide the first allelic frequency data of X-STR (X chromosomal) loci in the Turkish population. Blood samples were taken from unrelated individuals (135 males and 129 ...

Equipment and performance of the Q3D spectrometer installed at the tandem laboratory of Saclay

International Nuclear Information System (INIS)

Berthier, B.

1979-01-01

A quadrupole - dipole - dipole - dipole (Q3D) magnetic spectrometer with proportional gas counter which has been installed at the tandem laboratory of Saclay is described. Typical results are given indicating the performance of the apparatus in studies of heavy ion reactions at tandem energies for which good energy resolution and large solid angles are required. Improvements to allow the detection of heavier masses and less energetic ions with better energy resolution are planned. (U.K.)

CH(3)NH(3)PbI(3) perovskite / silicon tandem solar cells: characterization based optical simulations.

Science.gov (United States)

Filipič, Miha; Löper, Philipp; Niesen, Bjoern; De Wolf, Stefaan; Krč, Janez; Ballif, Christophe; Topič, Marko

2015-04-06

In this study we analyze and discuss the optical properties of various tandem architectures: mechanically stacked (four-terminal) and monolithically integrated (two-terminal) tandem devices, consisting of a methyl ammonium lead triiodide (CH(3)NH(3)PbI(3)) perovskite top solar cell and a crystalline silicon bottom solar cell. We provide layer thickness optimization guidelines and give estimates of the maximum tandem efficiencies based on state-of-the-art sub cells. We use experimental complex refractive index spectra for all involved materials as input data for an in-house developed optical simulator CROWM. Our characterization based simulations forecast that with optimized layer thicknesses the four-terminal configuration enables efficiencies over 30%, well above the current single-junction crystalline silicon cell record of 25.6%. Efficiencies over 30% can also be achieved with a two-terminal monolithic integration of the sub-cells, combined with proper selection of layer thicknesses.

JAEA-Tokai tandem annual report 2009. April 1, 2009 - March 31, 2010

International Nuclear Information System (INIS)

Matsuda, Makoto; Takeuchi, Suehiro

2010-12-01

The JAEA-Tokai tandem accelerator complex has been used in various research fields such as nuclear science and material science by researchers not only of JAEA but also from universities, research institutes and industrial companies. This annual report covers developments of accelerators and research activities carried out using the tandem accelerator, superconducting booster, and radioactive nuclear beam accelerator, from April 1, 2009 to March 31, 2010. Fifty-seven summary reports were categorized into seven research/development fields: (1) accelerator operation and development, (2) nuclear structure, (3) nuclear reaction, (4) nuclear chemistry, (5) nuclear theory, (6) atomic physics and solid state physics, (7) radiation effects in materials. This report also lists publications, meetings, personnel, committee members, cooperative researches and common use programs. The fifty-seven summary reports are indexed individually. (J.P.N.)

JAEA-Tokai tandem annual report 2008. April 1, 2008 - March 31, 2009

International Nuclear Information System (INIS)

Nagame, Yuichiro; Chiba, Satoshi; Mitsuoka, Shinichi

2009-11-01

The JAEA-Tokai tandem accelerator complex has been used in various research fields such as nuclear science and material science by researchers not only of JAEA but also from universities, research institutes and industrial companies. This annual report covers developments of accelerators and research activities carried out using the tandem accelerator, superconducting booster, and radioactive nuclear beam accelerator, from April 1, 2008 to March 31, 2009. Fifty-five summary reports were categorized into seven research/development fields: (1) accelerator operation and development, (2) nuclear structure, (3) nuclear reaction, (4) nuclear chemistry, (5) nuclear theory, (6) atomic physics and solid state physics, (7) radiation effects in materials. This report also lists publications, meetings, personnel, committee members, cooperative researches and common use programs. The fifty-five summary reports are indexed individually. (J.P.N.)

Highly efficient tandem OLED based on C{sub 60}/rubrene: MoO{sub 3} as charge generation layer and LiF/Al as electron injection layer

Energy Technology Data Exchange (ETDEWEB)

Liu, Yang [School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384 (China); Key Laboratory of Display Materials and Photoelectric Devices, Ministry of Education, Tianjin 300384 (China); Tianjin Key Laboratory of Photoelectric Materials and Devices, Tianjin 300384 (China); College of Science, Tianjin University of Technology, Tianjin 300384 (China); Wu, Xiaoming, E-mail: wxm@tjut.edu.cn [School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384 (China); Key Laboratory of Display Materials and Photoelectric Devices, Ministry of Education, Tianjin 300384 (China); Tianjin Key Laboratory of Photoelectric Materials and Devices, Tianjin 300384 (China); Xiao, Zhihui; Gao, Jian; Zhang, Juan; Rui, Hongsong; Lin, Xin; Zhang, Nan; Hua, Yulin [School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384 (China); Key Laboratory of Display Materials and Photoelectric Devices, Ministry of Education, Tianjin 300384 (China); Tianjin Key Laboratory of Photoelectric Materials and Devices, Tianjin 300384 (China); Yin, Shougen, E-mail: sgyin@tjut.edu.cn [School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384 (China); Key Laboratory of Display Materials and Photoelectric Devices, Ministry of Education, Tianjin 300384 (China); Tianjin Key Laboratory of Photoelectric Materials and Devices, Tianjin 300384 (China)

2017-08-15

Highlights: • Highly efficient blue fluorescent tandem OLEDs are fabricated. • The optimal tandem OLED consists of C{sub 60}/rubrene: MoO{sub 3} as a CGL and LiF/Al as an EIL. • Current efficiency and power efficiency of optimal tandem OLED is markedly enhanced. • The turn-on and driving voltages of optimal tandem OLED is obviously reduced. - Abstract: Tandem organic light-emitting diodes (OLEDs) have received much attention in solid-state lighting due to their high current efficiency, long lifetime and excellent stability. The highly efficient blue fluorescent tandem OLEDs based on the charge generation layer (CGL) of C{sub 60}/rubrene: MoO{sub 3} and the electron injection layer (EIL) of LiF/Al were fabricated. The ultra-thin Al layer in EIL was introduced to further increase electron injection from CGL to the emission unit. We found that the maximal current efficiency and power efficiency of optimal tandem device can reach to 43.1 cd/A and 15.1 lm/W, respectively, which are approximately 2.8 and 1.9 times compared with those of single-emissive-unit device. Moreover, compared with the traditional tandem device, the driving voltage of the optimal device is reduced by 6 V, and the turn-on voltage is reduced by 2.4 V. We analyzed the mechanism and characterization of these tandem devices. The effective charge separation and transport of C{sub 60}/rubrene: MoO{sub 3}, and excellent electron injection ability of ultra-thin Al layer are the main factors for the remarkable enhancement in both current efficiency and power efficiency of tandem OLEDs.

Control of surface thermal scratch of strip in tandem cold rolling

Science.gov (United States)

Chen, Jinshan; Li, Changsheng

2014-07-01

The thermal scratch seriously affects the surface quality of the cold rolled stainless steel strip. Some researchers have carried out qualitative and theoretical studies in this field. However, there is currently a lack of research on effective forecast and control of thermal scratch defects in practical production, especially in tandem cold rolling. In order to establish precise mathematical model of oil film thickness in deformation zone, the lubrication in cold rolling process of SUS410L stainless steel strip is studied, and major factors affecting oil film thickness are also analyzed. According to the principle of statistics, mathematical model of critical oil film thickness in deformation zone for thermal scratch is built, with fitting and regression analytical method, and then based on temperature comparison method, the criterion for deciding thermal scratch defects is put forward. Storing and calling data through SQL Server 2010, a software on thermal scratch defects control is developed through Microsoft Visual Studio 2008 by MFC technique for stainless steel in tandem cold rolling, and then it is put into practical production. Statistics indicate that the hit rate of thermal scratch is as high as 92.38%, and the occurrence rate of thermal scratch is decreased by 89.13%. Owing to the application of the software, the rolling speed is increased by approximately 9.3%. The software developed provides an effective solution to the problem of thermal scratch defects in tandem cold rolling, and helps to promote products surface quality of stainless steel strips in practical production.

High-efficiency, monolithic, multi-bandgap, tandem photovoltaic energy converters

Science.gov (United States)

Wanlass, Mark W [Golden, CO

2011-11-29

A monolithic, multi-bandgap, tandem solar photovoltaic converter has at least one, and preferably at least two, subcells grown lattice-matched on a substrate with a bandgap in medium to high energy portions of the solar spectrum and at least one subcell grown lattice-mismatched to the substrate with a bandgap in the low energy portion of the solar spectrum, for example, about 1 eV.

Mass spectrometry and tandem mass spectrometry of citrus limonoids.

Science.gov (United States)

Tian, Qingguo; Schwartz, Steven J

2003-10-15

Methods for atmospheric pressure chemical ionization tandem mass spectrometry (APCI-MS/MS) of citrus limonoid aglycones and electrospray ionization tandem mass spectrometry (ESI-MS/MS) of limonoid glucosides are reported. The fragmentation patterns of four citrus limonoid aglycones (limonin, nomilin, obacunone, and deacetylnomilin) and six limonoid glucosides, that is, limonin 17-beta-D-glucopyranoside (LG), nomilin 17-beta-D-glucopyranoside (NG), nomilinic acid 17-beta-D-glucopyranoside (NAG), deacetyl nomilinic acid 17-beta-D-glucopyranoside (DNAG), obacunone 17-beta-D-glucopyranoside (OG), and obacunoic acid 17-beta-D-glucopyranoside (OAG) were investigated using a quadruple mass spectrometer in low-energy collisionally activated dissociation (CAD). The four limonoid aglycones and four limonoid glucosides (LG, OG, NAG, and DNAG) were purified from citrus seeds; the other two limonoid glucosides (NG and OAG) were tentatively identified in the crude extract of grapefruit seeds by ESI mass spectrometry in both positive and negative ion analysis. Ammonium hydroxide or acetic acid was added to the mobile phase to facilitate ionization. During positive ion APCI analysis of limonoid aglycones, protonated molecular ion, [M + H]+, or adduct ion, [M + NH3 + H]-, was formed as base peaks when ammonium hydroxide was added to the mobile phase. Molecular anions or adduct ions with acetic acid ([M + HOAc - H] and [M + HOAc]-) or a deprotonated molecular ion were produced during negative ion APCI analysis of limonoid aglycones, depending on the mobile-phase modifier used. Positive ion ESI-MS of limonoid glucosides produced adduct ions of [M + H + NH3]+, [M + Na]+, and [M + K]+ when ammonium hydroxide was added to the mobile phase. After collisionally activated dissociation (CAD) of the limonoid aglycone molecular ions in negative ion APCI analysis, fragment ions indicated structural information of the precursor ions, showing the presence of methyl, carboxyl, and oxygenated ring

Status of the Tandem Mirror Experiment-Upgrade (TMX-U) diagnostic system

International Nuclear Information System (INIS)

Coutts, G.W.; Coffield, F.E.; Hornady, R.S.

1983-01-01

This paper presents the current status of the Tandem Mirror Experiment-Upgrade (TMX-U) diagnostics system. For the initial instruments active on TMX-U, the expansions or upgrades that have been implemented are outlined. For the newly added systems, more implementation details are presented

Importance Sampling Simulation of Population Overflow in Two-node Tandem Networks

NARCIS (Netherlands)

Nicola, V.F.; Zaburnenko, T.S.; Baier, C; Chiola, G.; Smirni, E.

2005-01-01

In this paper we consider the application of importance sampling in simulations of Markovian tandem networks in order to estimate the probability of rare events, such as network population overflow. We propose a heuristic methodology to obtain a good approximation to the 'optimal' state-dependent

Classical tandem-source dwelling covering the entire uterus. Essential in modern intracavitary radiotherapy for cervical cancer?

International Nuclear Information System (INIS)

Ohara, Kiyoshi; Nemoto, Keiko; Ohnishi, Kayoko; Hashimoto, Takayuki; Fukumitsu, Nobuyoshi; Hata, Masaharu; Sugahara, Shinji; Tokuuye, Koichi; Akine, Yasuyuki

2007-01-01

We investigated whether conventional tandem-source dwelling to cover the entire uterus, classically regarded as the target volume, is necessary in modem intracavitary radiotherapy (ICRT) for cervical cancer. The study included 95 cervical squamous cell carcinoma patients treated by high-dose-rate ICRT (point A dose was 6.0 Gy, with three to five insertions per patient) after external beam radiotherapy (EBRT), with central pelvic doses of 12-50 Gy. The tandem-source dwell length was adjusted to the target volume specified by magnetic resonance (MR) imaging. A tandem applicator was inserted as far as the uterine fundus in accordance with the post-EBRT MR-assessed cavity length. The pre-EBRT MR-specified target volume was used for the dwell-length adjustment. The safety of the dwell-length adjustment was assessed in terms of treatment failure. The dwell-length adjustment was made in 248 of 366 total insertions with a dwell-length reduction of 5-55 mm (median 15 mm) at the corpus. Pelvic failure was identified in 22 patients with a 2-year pelvic disease-free survival rate of 75.6% but without evidence of failure at dwelling-skipped corpuses. Given after pelvic EBRT and ICRT of full-length dwelling in part, which may have eradicated possible subclinical extension, adjustment of the tandem-source dwell length to the MR-specified target volume appeared to be safe. (author)

Field Test: Results of Tandem Walk Performance Following Long-Duration Spaceflight

Science.gov (United States)

Rosenberg, M. J. F.; Reschke, M. F.; Cerisano, J. M.; Kofman, I. S.; Fisher, E. A.; Gadd, N. E.; May-Phillips, T. R.; Lee, S. M. C.; Laurie, S. S.; Stenger, M. B.;

Front Surface Tandem Filters using Sapphire (Al2O3) Substrates for Spectral Control in thermophotovoltaic Energy Conversion Systems

International Nuclear Information System (INIS)

T Rahmlow, Jr.; J Lazo-Wasem; E Gratrix; P Fourspring; D DePoy

2005-01-01

Front surface filters provide an effective means of improving thermophotovoltaic (TPV) system efficiency through spectral control of incident radiant energy. A front surface filter reflects the below band gap photons that can not be converted by the TPV cell back towards the high temperature radiator and allows convertible above band gap photons to pass through the filter into the TPV cell for conversion to electricity. The best spectral control efficiency to date has been demonstrated by front surface, tandem filters that combine an interference filter and an InPAs layer (plasma filter) in series. The InPAs material is a highly doped, epitaxially grown layer on an InP substrate. These tandem filter designs have been fabricated with energy and angle weighted spectral efficiencies of 76% for TPV cells with a 2.08(micro)m (0.6eV) band gap [1]. An alternative to the InPAs layer on an InP substrate is an Al 2 O 3 (sapphire) substrate. The use of Al 2 O 3 may increase transmission of above band gap photons, increase the mechanical strength of the tandem filter, and lower the cost of the tandem filter, all at the expense of lower spectral efficiency. This study presents design and fabrication results for front surface tandem filters that use an Al 2 O 3 substrate for 2.08(micro)m band gap TPV cells

Scaling of the optical parameters for the JAERI tandem accelerator

International Nuclear Information System (INIS)

Hanashima, S.; Minehara, E.

1986-01-01

A scaling rule of the beam optical parameters was adopted for computer-aided beam transport in the JAERI tandem accelerator. Tests have shown that the computer program can transport a specified beam in a short time using a reference parameter set. Problems of ion source control and accuracy of the optical devices are also discussed

Self-similarity of far wake behind tandem of two disks

DEFF Research Database (Denmark)

Okulov, Valery; Litvinov, I. V.; Naumov, I. V.

2017-01-01

the wake ceased to differ from the background of natural turbulent fluctuations of the incident flow. It has been found that the position of the second disk in the tandem affects the energy loss in the wake due to its expansion but does not influence the decay. The revealed patterns in the wake development...

Annual report of the Tandem Accelerator Center, University of Tsukuba

International Nuclear Information System (INIS)

1985-01-01

This annual report covers the work carried out at the Tandem Accelerator Center, University of Tsukuba, during fiscal year 1984. The 12 UD Pelletron tandem accelerator was operated very stably. In addition, the heavy ion post accelerator with interdigital-H structure has worked well, providing additional energy of 2 MeV per charge for heavy ions. The constructions of a new Lamb-shift polarized ion source, a multi-computer control system for the ion sources of the UTTA, an electrostatic inflection system of incident ions for the UTTA, a new beam bunching system, and a new SF 6 gas handling system were under way. The development and performance test of various radiation detector systems were carried out. Two thirds of the research works were performed by using the beam from the Lamb-shift polarized ion source (PIS). A newly constructed fast spin state interchange control system for the PIS made polarization experiment more effective and accurate. The research activities in the fields of nuclear physics, atomic and solid state physics, and biology and medical science are reported. (Kako, I.)

Simulations of emission from microcavity tandem organic light-emitting diodes

International Nuclear Information System (INIS)

Biswas, Rana; Xu, Chun; Zhao, Weijun; Liu, Rui; Shinar, Ruth; Shinar, Joseph

2011-01-01

Microcavity tandem organic light-emitting diodes (OLEDs) are simulated and compared to experimental results. The simulations are based on two complementary techniques: rigorous finite element solutions of Maxwell's equations and Fourier space scattering matrix solutions. A narrowing and blue shift of the emission spectrum relative to the noncavity single unit OLED is obtained both theoretically and experimentally. In the simulations, a distribution of emitting sources is placed near the interface of the electron transport layer tris(8-hydroxyquinoline) Al (Alq 3 ) and the hole transport layer (N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)benzidine) (α-NPB). Far-field electric field intensities are simulated. The simulated widths of the emission peaks also agree with the experimental results. The simulations of the 2-unit tandem OLEDs shifted the emission to shorter wavelength, in agreement with experimental measurements. The emission spectra's dependence on individual layer thicknesses also agreed well with measurements. Approaches to simulate and improve the light emission intensity from these OLEDs, in particular for white OLEDs, are discussed.

Picosecond ion pulses from an EN tandem created by a femtosecond Ti:sapphire laser

International Nuclear Information System (INIS)

Carnes, K.D.; Cocke, C.L.; Chang, Z.; Ben-Itzhak, I.; Needham, H.V.; Rankin, A.

2007-01-01

As the James R. Macdonald Laboratory at Kansas State University continues its transformation from an ion collisions facility to an ultrafast laser/ion collisions facility, we are looking for novel ways to combine our traditional accelerator expertise with our new laser capabilities. One such combination is to produce picosecond pulses of stripping gas ions in the high energy accelerating tube of our EN tandem by directing ∼100 fs, sub-milliJoule laser pulses up the high energy end of the tandem toward a focusing mirror at the terminal. Ion pulses from both stripping and residual gas have been produced and identified, with pulse widths thus far on the order of a nanosecond. This width represents an upper limit, as it is dominated by pulse-to-pulse jitter in the ion time-of-flight (TOF) and is therefore not a true representation of the actual pulse width. In this paper, we describe the development process and report on the results to date. Conditions limiting the minimum temporal pulse width, such as tandem terminal ripple, thermal motion of the gas and space charge effects, are also outlined

Octopole and hexapole end cells for tandem mirrors

International Nuclear Information System (INIS)

Devoto, R.S.

1985-01-01

To date, nearly all operating or planned tandem mirror experiments use quadrupole magnetic fields in the end cells for stabilization of magnetohydrodynamic (MHD) instabilities. A disadvantage with quadrupole fields is the considerable aximuthal asymmetry in the magnetic field. As a result, those center-cell ions which pass into the end cell can suffer a radial deflection and be lost by radial diffusion. The diffusion can be minimized by adding C-coils to the end cell to symmetrize the geodesic curvature in the end cell. Very small radial deflection can be obtained on each field line. Such a method is used in the design of the MFTF-B experiment and the MARS reactor. A disadvantage of this approach is the large number of coils required. In addition, since ions drift azimuthally as they reflect in the end cell, even perfect cancellation on individual field lines will, in general, not lead to zero radial diffusion. One way to form a more symmetric field in the end cells is to use multipoles higher than quadrupole. The use of an octopole end cell for a small tandem-mirror reactor was recently proposed/sup L/ and has been adopted for the miniMARS reactor study. In this paper the author discusses some feature of octopole, and to a lesser extent, hexapole end cells in both reactor and experimental (MFTF-B) applications

Development of high current injector for tandem accelerator

Energy Technology Data Exchange (ETDEWEB)

Baba, Takashi; Iwamoto, Eiji [Nissin - High Voltage Co. Ltd., Kyoto (Japan); Kishimoto, Naoki; Saito, Tetsuya; Mori, Yoshiharu

1997-02-01

The development of the electrostatic type tandem accelerators has been carried out so far, but by the recent remarkable progress of negative ion sources, the beam current which was inconceivable so far has become obtainable, and the use as the electrostatic type tandem accelerators is expanding rapidly. The problem which must be solved in the development of a high energy, large current heavy ion injection device is the development of an injector. As to the generation of negative ions, by the development of plasma sputter negative ion sources, the almost satisfactory performance has been obtained in beam current, emittance, life and so on, but as for the transport and control of generated negative ion beam, there is the large problem of spatial charge effect. This time, the verifying test on this problem was carried out, therefore, its contents and results are reported. The equipment which was developed this time was delivered to the Institute for Materials Research. Its specifications are shown. The whole constitution, negative ion source, and beam transport system are described. Beam generation test and spatial charge effect test are reported. The test stand was made, and in the verifying test, the maximum beams of 4 mA in Cu and 3 mA in Ni were able to be generated and transported. The effect of the countermeasures to spatial charge effect was confirmed. (K.I.)

Optical properties and thermal stability of TiAlN/AlON tandem absorber prepared by reactive DC/RF magnetron sputtering

Energy Technology Data Exchange (ETDEWEB)

Barshilia, Harish C.; Selvakumar, N.; Rajam, K.S. [Surface Engineering Division, National Aerospace Laboratories, Bangalore 560 017 (India); Biswas, A. [Spectroscopy Division, Bhabha Atomic Research Center, Mumbai 400 085 (India)

2008-11-15

Spectrally selective TiAlN/AlON tandem absorbers were deposited on copper and stainless steel substrates using a reactive DC/RF magnetron sputtering system. The compositions and thicknesses of the individual component layers were optimized to achieve high absorptance ({alpha}=0.931-0.942) and low emittance ({epsilon}=0.05-0.06) on copper substrate. The experimental spectroscopic ellipsometric data have been fitted with the theoretical models to derive the dispersion of the optical constants (n and k). In order to study the thermal stability of the tandem absorbers, they were subjected to heat treatment (in air and vacuum) for different durations and temperatures. The tandem absorber deposited on Cu substrates exhibited high solar selectivity ({alpha}/{epsilon}) of 0.946/0.07 even after heat treatment in air up to 600 C for 2 h. At 625 C, the solar selectivity decreased significantly on Cu substrates (e.g., {alpha}/{epsilon}=0.924/0.30). The tandem absorber on Cu substrates was also stable in air up to 100 h at 400 C with a solar selectivity of 0.919/0.06. Studies on the accelerated aging tests indicated that the activation energy for the degradation of the tandem absorber is of the order of 100 kJ/mol. (author)

A tandem regression-outlier analysis of a ligand cellular system for key structural modifications around ligand binding.

Science.gov (United States)

Lin, Ying-Ting

2013-04-30

A tandem technique of hard equipment is often used for the chemical analysis of a single cell to first isolate and then detect the wanted identities. The first part is the separation of wanted chemicals from the bulk of a cell; the second part is the actual detection of the important identities. To identify the key structural modifications around ligand binding, the present study aims to develop a counterpart of tandem technique for cheminformatics. A statistical regression and its outliers act as a computational technique for separation. A PPARγ (peroxisome proliferator-activated receptor gamma) agonist cellular system was subjected to such an investigation. Results show that this tandem regression-outlier analysis, or the prioritization of the context equations tagged with features of the outliers, is an effective regression technique of cheminformatics to detect key structural modifications, as well as their tendency of impact to ligand binding. The key structural modifications around ligand binding are effectively extracted or characterized out of cellular reactions. This is because molecular binding is the paramount factor in such ligand cellular system and key structural modifications around ligand binding are expected to create outliers. Therefore, such outliers can be captured by this tandem regression-outlier analysis.

SEBIM pilot operated tandems. A new solution for Darlington NGS bleed condenser relief valves

International Nuclear Information System (INIS)

Paetzold, H.; Hera, V.; Schaumburg, G.

1996-01-01

Following incidents at Pickering, Wolsung and Bruce NGS, involving instability of bleed condenser relief valves, Darlington station decided to replace the spring loaded RV's by new pilot operated SEBIM tandem valves. This paper is presenting the approach taken, the design and the testing of the new solution, as well as some of the computer modeling work performed in connection with this project. The SEBIM tandems, following successful testing in France, will be installed in Darlington Unit 2, this spring. The new valves can perform with absence of instability and prevent a LOCA incident due to their design, which includes a protection and a redundant valve in series. (author)

Tandem ring-closing metathesis/isomerization reactions for the total synthesis of violacein

DEFF Research Database (Denmark)

Petersen, Mette Terp; Nielsen, Thomas Eiland

2013-01-01

A series of 5-substituted 2-pyrrolidinones was synthesized through a one-pot ruthenium alkylidene-catalyzed tandem RCM/isomerization/nucleophilic addition sequence. The intermediates resulting from RCM/isomerization showed reactivity toward electrophiles in aldol condensation reactions which...

WE-A-17A-05: Differences in Applicator Configuration and Dwell Loading Between Standard and Image-Guided Tandem and Ring (T and R) HDR Brachytherapy

Energy Technology Data Exchange (ETDEWEB)

Damato, A; Cormack, R; Bhagwat, M; Buzurovic, I; Lee, L; Viswanathan, A [Brigham and Women' s Hospital, Boston, MA (United States)

2014-06-15

Purpose: To investigate differences in: (i) relative location of the tandem and the ring compared to a rigid standard applicator model; and (ii) relative loading and changes in loading pattern between standard and image-guided planning. Methods: All T and R insertions performed in 2013 in our institution under CT- or MR-guidance were analyzed. Standard plans were generated using library applicator models with a fixed relationship between ring and tandem, standardized uniform dwell loading and normalization to point A. The graphic plans and the associated standard-plan dwell configurations were compared: the rings were rigidly registered, and the residual tandem shift, rotation and maximum distance between plan tandem dwell and corresponding model tandem dwell were calculated. The normalization ratio (NR = the ratio of graphic versus standard-plan total reference air kerma [TRAK]), the general loading difference (GLD = the difference between graphic and standard ratios of the tandem versus the ring TRAK), and the percent standard deviation (SD% = SD/mean) of the tandem and the ring TRAK for the graphic plan (all standard-plans SD% = 0) were calculated. Results: 71 T and R were analyzed. Residual tandem shift, rotation and maximum corresponding dwell distance were 1.2±0.8mm (0.4±0.4mm lateral, 0.9±0.8mm craniocaudal, 0.4±0.3mm anterior-posterior), 2.3±1.9deg and 3.4±2.3mm. NR was 0.86±0.11 indicating a lower overall loading of the graphic compared to the standard plans. GLD was -0.12±0.16 indicating a modest increased ring loading relative to the tandem in the graphic plans. SD% was 2.1±1.6% for tandem and 2.8±1.9% for ring, indicating small deviations from uniform loading. Conclusion: Variability in the relative locations of the tandem and the ring necessitates the independent registration of each component model for accurate digitization. Our clinical experience suggests that graphically planned T and R results on average in a lower total dose to the

WE-A-17A-05: Differences in Applicator Configuration and Dwell Loading Between Standard and Image-Guided Tandem and Ring (T and R) HDR Brachytherapy

International Nuclear Information System (INIS)

Damato, A; Cormack, R; Bhagwat, M; Buzurovic, I; Lee, L; Viswanathan, A

2014-01-01

Purpose: To investigate differences in: (i) relative location of the tandem and the ring compared to a rigid standard applicator model; and (ii) relative loading and changes in loading pattern between standard and image-guided planning. Methods: All T and R insertions performed in 2013 in our institution under CT- or MR-guidance were analyzed. Standard plans were generated using library applicator models with a fixed relationship between ring and tandem, standardized uniform dwell loading and normalization to point A. The graphic plans and the associated standard-plan dwell configurations were compared: the rings were rigidly registered, and the residual tandem shift, rotation and maximum distance between plan tandem dwell and corresponding model tandem dwell were calculated. The normalization ratio (NR = the ratio of graphic versus standard-plan total reference air kerma [TRAK]), the general loading difference (GLD = the difference between graphic and standard ratios of the tandem versus the ring TRAK), and the percent standard deviation (SD% = SD/mean) of the tandem and the ring TRAK for the graphic plan (all standard-plans SD% = 0) were calculated. Results: 71 T and R were analyzed. Residual tandem shift, rotation and maximum corresponding dwell distance were 1.2±0.8mm (0.4±0.4mm lateral, 0.9±0.8mm craniocaudal, 0.4±0.3mm anterior-posterior), 2.3±1.9deg and 3.4±2.3mm. NR was 0.86±0.11 indicating a lower overall loading of the graphic compared to the standard plans. GLD was -0.12±0.16 indicating a modest increased ring loading relative to the tandem in the graphic plans. SD% was 2.1±1.6% for tandem and 2.8±1.9% for ring, indicating small deviations from uniform loading. Conclusion: Variability in the relative locations of the tandem and the ring necessitates the independent registration of each component model for accurate digitization. Our clinical experience suggests that graphically planned T and R results on average in a lower total dose to the

High work function transparent middle electrode for organic tandem solar cells

NARCIS (Netherlands)

Moet, D. J. D.; de Bruyn, P.; Blom, P. W. M.

2010-01-01

The use of poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) in combination with ZnO as middle electrode in solution-processed organic tandem solar cells requires a pH modification of the PEDOT:PSS dispersion. We demonstrate that this neutralization leads to a reduced work function

JAERI tandem annual report 2002. April 1, 2002 - March 31, 2003

International Nuclear Information System (INIS)

Takeuchi, Suehiro; Oshima, Masumi; Ishii, Tetsuro; Nagame, Yuichiro; Chiba, Satoshi; Sataka, Masao

2003-11-01

This annual report describes research activities which have been performed with the JAERI tandem accelerator and the Van de Graaff accelerator from April 1, 2002 to March 31, 2003. Summary reports of 54 papers, and lists of publication, personnel and cooperative research with universities are contained. (author)

JAERI TANDEM annual report 2000. April 1, 2000 - March 31, 2001

Energy Technology Data Exchange (ETDEWEB)

Takeuchi, Suehiro; Ikezoe, Hiroshi; Chiba, Satoshi; Nagame, Yuichiro; Sataka, Masao; Iwamoto, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] (eds.)

2001-11-01

This annual report describes research activities which have been performed with the JAERI tandem accelerator and the Van de Graaff accelerator from April 1, 2000 to March 31, 2001. Summary reports of 46 papers, and lists of publication, personnel and cooperative research with universities are contained. (author)

JAERI tandem annual report 2001. April 1, 2001 - March 31, 2002

Energy Technology Data Exchange (ETDEWEB)

Takeuchi, Suehiro; Ikezoe, Hiroshi; Chiba, Satoshi; Nagame, Yuichiro; Sataka, Masao; Iwamoto, Akira (eds.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2002-11-01

This annual report describes research activities which have been performed with the JAERI tandem accelerator and the Van de Graaff accelerator from April 1, 2001 to March 31, 2002. Summary reports of 48 papers, and lists of publication, personnel and cooperative research with universities are contained. (author)