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1.
Rev Sci Instrum ; 93(12): 123505, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586937

RESUMO

High resolution spectroscopy on the Tokamak à Configuration Variable (TCV) divertor plasma provided Doppler broadening measurements to infer the ion and neutral temperature of injected helium gas. This paper presents the Divertor Spectroscopy System's (DSS) access to He II ion temperature measurements over a broad range, ≈0.5-15 eV, with an uncertainty of <10% for most of the studied plasma discharges. TCV's shaping flexibility was employed to validate these measurements against Thomson scattering across the DSS lines of sight. In detachment-related experiments, Ti(He II) ≃ Te, making this diagnostic a reliable thermometer along the divertor leg plasma over the wide range of magnetic equilibria and divertor configurations achievable in TCV. A detailed description of the diagnostic hardware, data analysis, and sources of uncertainty is presented.

2.
Nat Commun ; 12(1): 1105, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33597525

RESUMO

In magnetic confinement thermonuclear fusion the exhaust of heat and particles from the core remains a major challenge. Heat and particles leaving the core are transported via open magnetic field lines to a region of the reactor wall, called the divertor. Unabated, the heat and particle fluxes may become intolerable and damage the divertor. Controlled 'plasma detachment', a regime characterized by both a large reduction in plasma pressure and temperature at the divertor target, is required to reduce fluxes onto the divertor. Here we report a systematic approach towards achieving this critical need through feedback control of impurity emission front locations and its experimental demonstration. Our approach comprises a combination of real-time plasma diagnostic utilization, dynamic characterization of the plasma in proximity to the divertor, and efficient, reliable offline feedback controller design.

3.
Rev Sci Instrum ; 90(12): 123514, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31893833

RESUMO

This work presents a novel, real-time capable, 10-channel Multispectral Advanced Narrowband Tokamak Imaging System installed on the TCV tokamak, MANTIS. Software and hardware requirements are presented together with the complete system architecture. The image quality of the system is assessed with emphasis on effects resulting from the narrowband interference filters. Some filters are found to create internal reflection images that are correlated with the filters' reflection coefficient. This was measured for selected filters where significant absorption (up to 65% within ∼70 nm of the filter center) was measured. The majority of this was attributed to the filter's design, and several filters' performance is compared. Tailored real-time algorithms exploiting the system's capabilities are presented together with benchmarks comparing polling and event based synchronization. The real-time performance is demonstrated with a density ramp discharge performed on TCV. The behavior of spectral lines' emission from different plasma species and their interpretation are qualitatively described.

4.
Rev Sci Instrum ; 89(10): 103503, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399774

RESUMO

The Multi-Spectral Imaging system is a new diagnostic that captures simultaneous spectrally filtered images from a common line of sight while maintaining a large étendue and high throughput. Imaging several atomic line intensities simultaneously may enable numerous measurement techniques. By making a novel modification of a polychromator layout, the MSI sequentially filters and focuses images onto commercial CMOS cameras while exhibiting minimal vignetting and aberrations. A four-wavelength system was initially installed and tested on Alcator C-Mod and subsequently moved to TCV. The images are absolutely calibrated and spatially registered enabling 2D mappings of atomic line ratios and absolute line intensities. The spectral transmission of the optical system was calibrated using an integrating sphere of known radiance. The images are inverted by cross-referencing points on TCV with a computer-aided design (CAD) model.


Assuntos
Diagnóstico por Imagem/instrumentação , Calibragem , Análise Espectral
5.
Tob Control ; 12(4): 406-10, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14660777

RESUMO

AIM: To compare the burning characteristics of the tobacco and paper of manufactured and hand rolled cigarettes, and set a fire safety standard of manufacture to largely reduce the fire risk from discarded cigarettes. METHODS: (1) Cigarette extinction test of ignition strength: 40 cigarettes per brand, lit and placed on 15 layers of filter paper, in accordance with ASTM test standard E2187-02. (2) Citrate extracted by 0.1N hydrochloric acid from cigarette papers and from tobacco in manufactured cigarettes, the supernatant analysed by high performance liquid chromatography using ultraviolet visual light spectrophotometer. (3) Survey of 750 nationally representative adults age 18 years and over, by telephone, including 184 smokers. MATERIALS: (a) New Zealand made Holiday, and Horizon, and US made Marlboro manufactured cigarettes; (b) US manufactured Merit with banded paper; (c) Holiday, Horizon and Marlboro hand rolling tobaccos, hand rolled in Rizla cigarette papers; (d) manufactured cigarettes as in (a), reconstructed using Rizla hand rolling cigarette papers. RESULTS: 1. (a) For each brand of manufactured cigarettes, 40/40 burnt full length; (b) for Merit banded paper cigarettes 29/40 (73%) burnt full length; (c) for each brand of hand rolled cigarettes 0/40 burnt full length; (d) 0/40 manufactured cigarettes reconstructed with Rizla hand rolling paper burnt full length. 2. Citrate content: (a) In manufactured cigarette papers: 0.3-0.8 mg; in tobacco of manufactured cigarettes: Holiday 0, Horizon 0, Marlboro 8.8 mg; (b) Merit: in banded paper 0.418 mg; in tobacco 10.23 mg; (c) In hand rolled cigarettes: in the papers < 0.08 mg; in hand rolled tobacco 13.3-15.0 mg; (d) In hand rolling papers of reconstructed cigarettes: < 0.018 mg. 3. Requiring manufactured cigarettes to compulsorily self-extinguish when left unattended was supported by 67% of smokers, 61% of manufactured cigarette smokers, 82% of hand rolled smokers, and by 68% of non-smokers. CONCLUSION: The wrapping paper is a key determinant of whether or not unpuffed cigarettes burn their full length. Using international test methods, popular brands of manufactured cigarettes all burnt full length, but none did so when re-wrapped in hand rolling cigarette paper. This provides a ready-to-hand smoker acceptable standard for reducing ignition potential from manufactured cigarettes, as a basis for regulation or litigation.


Assuntos
Qualidade de Produtos para o Consumidor/legislação & jurisprudência , Incêndios/prevenção & controle , Papel/normas , Fumar , Adolescente , Adulto , Queimaduras/prevenção & controle , Qualidade de Produtos para o Consumidor/normas , Estudos de Viabilidade , Inquéritos Epidemiológicos , Humanos , Padrões de Referência
6.
Ann Intern Med ; 104(1): 26-32, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3940502

RESUMO

A 40-year-old man had regular cyclic episodes of weight gain and eosinophilic myositis associated with hyperimmunoglobulin-E and hypereosinophilia for 9 years. During the episodes his body weight increased up to 10.8%; eosinophil counts reached 41.3 X 10(-9) cells/L; and IgE levels reached 18 000 IU/mL. These values changed regularly in a definite sequence relative to the clinical state. Attempts to document a parasitic cause were unsuccessful, and several courses of anthelmintic therapy were ineffective. An oral dose of prednisone, 10 mg/d, begun in July 1982 resulted in an immediate lessening of the severity of the episodes and a progressive lengthening of the cycle from 35 to 170 days. No further episodes have occurred since March 1984. The patient is fit and well on prednisone therapy, 12.5 mg on alternate days. This apparently unique syndrome has a benign course and is a cyclic disease involving skeletal muscle as the target organ.


Assuntos
Eosinofilia/imunologia , Hipergamaglobulinemia/imunologia , Imunoglobulina E/análise , Miosite/imunologia , Adulto , Creatina Quinase/metabolismo , Esquema de Medicação , Eosinofilia/tratamento farmacológico , Humanos , Hipergamaglobulinemia/tratamento farmacológico , Isoenzimas , Masculino , Miosite/sangue , Miosite/tratamento farmacológico , Periodicidade , Prednisona/uso terapêutico , Síndrome
7.
N Z Med J ; 90(641): 98-100, 1979 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-290921

RESUMO

The recent epidemic of cholera on the Pacific Ocean atoll of Tarawa, Gilbert Islands renewed interest in the use of coconut water as a rehydration fluid. Fifty-one samples of coconut water from Tarawa were analysed for a variety of constituents to assess its potential usefulness in the oral and parenteral rehydration of patients with cholera and other severe forms of gastroenteritis. Compared to oral rehydration fluids known to be effective in cholera, coconut water was found to have adequate potassium and glucose content, however was relatively deficient in sodium, chloride and bicarbonate. The addition of table salt to the coconut water is suggested to compensate for the sodium and chloride deficiency. In areas of the world where coconuts are plentiful, the advantages of sterility, availability and acceptability make coconut water theoretically feasible for the oral rehydration of patients with severe gastroenteritis when conventional fluids are unavailable.


Assuntos
Cocos , Desidratação/terapia , Água , Cálcio/análise , Glucose/análise , Humanos , Lactente , Magnésio/análise , Micronésia , Potássio/análise , Sódio/análise , Água/análise
8.
Br J Haematol ; 42(4): 575-83, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-476009

RESUMO

Some boys with X-linked chronic granulomatous disease (CGD) have red cells of the rare McLeod phenotype in the Kell blood group system. Only one example of this phenotype has previously been described in a non-CGD subject. We have studied a 10-year-old boy and a maternal brother who do not have CGD and whose red cells are of the McLeod type . The boy presented as a haematological problem with red-cell abnormalities. These were acanthocytosis, anisocytosis and 'tailing' in the osmotic fragility curve, changes now known to occur with the McLeod phenotype. Subsequent studies revealed his rare blood group. A family study has established that an uncle also has acanthocytic red cells and the McLeod phenotype. In addition the boy's sister, mother and maternal grandmother all show red-cell mosaicism with double populations of McLeod acanthocytes and normal red cells of common Kell type. The gene that determines inheritance of the McLeod phenotype is X-linked and the mosaicism present in female carriers is believed to result from X chromosome inactivation by the Lyon effect. The study provides further evidence that the McLeod phenotype arises by inheritance of a variant X-linked modifying gene and not through inheritance of a variant gene at the Kell autosomal locus. It also represents the first occasion that a person of rare blood group has been recognized because of an associated anomaly in red cell morphology.


Assuntos
Acantócitos , Acantócitos/ultraestrutura , Anemia Hemolítica Congênita/genética , Antígenos de Grupos Sanguíneos/genética , Eritrócitos Anormais , Sistema do Grupo Sanguíneo de Kell/genética , Acantócitos/análise , Adulto , Idoso , Anemia Hemolítica Congênita/sangue , Criança , Membrana Eritrocítica/análise , Eritrócitos Anormais/análise , Eritrócitos Anormais/ultraestrutura , Feminino , Humanos , Masculino , Lipídeos de Membrana/sangue , Microscopia Eletrônica de Varredura , Fragilidade Osmótica , Linhagem , Fenótipo , Fosfolipídeos/sangue
9.
Appl Environ Microbiol ; 35(2): 317-22, 1978 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16345271

RESUMO

The nutritional requirements of Selenomonas ruminantium HD4 for growth on glucose, glycerol, or lactate were investigated to clarify the results of previous studies and to relate the nutrition of the organism to its physiology. The organism required l-aspartate, CO(2), p-aminobenzoic acid, and biotin for growth on a lactate-salts medium that contained small amounts of dithiothreitol. Aspartate could be replaced by l-malate or fumarate but not by succinate or l-asparagine. Requirements for growth with glycerol as an energy source were similar, except that aspartate was not required. With glucose as the energy source, neither aspartate nor p-aminobenzoic acid was required, but a requirement for volatile fatty acids, which could be met by n-valerate, was observed. CO(2) was required for growth on lactate or glycerol but not on glucose on complex media containing Trypticase and yeast extract. Sulfide could be used as the sole source of sulfur.

10.
Appl Environ Microbiol ; 33(4): 1009-10, 1977 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-869523

RESUMO

An anaerobic cellulolytic bacterium, identified as a Bacteroides sp., was present in 10(-8) g of feces from only one of five human subjects.


Assuntos
Bacteroides/isolamento & purificação , Fezes/microbiologia , Adulto , Bacteroides/metabolismo , Celulose/metabolismo , Meios de Cultura , Humanos
11.
N Z Med J ; 82(550): 267-9, 1975 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-128713

RESUMO

The presentation of one individual with HBAg-positive hepatitis in a semi-closed community led to the testing of 262 intellectually-handicapped persons and staff-members and to the detection of 12 others who were HBAg-positive. Only the presenting case and one other became unwell with hepatitis. Three other HBAg-positive individuals became negative within three months, none showing clinical or biochemical evidence of hepatitis. The remaining eight persons were still HBAg-positive six months later. Four of these had biochemical abnormalities suggesting they had suffered anicteric hepatitis while the remainder, three of whom had Down's syndrome, had no such changes and are therefore considered to be carriers of the infective agent.


Assuntos
Instalações de Saúde , Antígenos da Hepatite B , Hepatite B/epidemiologia , Deficiência Intelectual , Portador Sadio/epidemiologia , Síndrome de Down/complicações , Feminino , Hepatite B/complicações , Humanos , Masculino , Nova Zelândia
12.
Appl Microbiol ; 29(4): 480-3, 1975 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-804850

RESUMO

Selenomonas ruminantium is a nonsporeforming anaerobe that ferments carbohydrates primarily to lactate, propionate, acetate and CO2. H2 production by this species has not been previously reported. We found, however, that some strains produce trace amounts of H2 which can be detected by sensitive gas chromatographic procedures. H2 production is increased markedly, in some cases almost 100-fold, when the selenomonads are co-cultured with methane-producing bacteria. Growth of the methane-producing bacteria depends on H2 production by the selenomonads and the subsequent use of H2 for the reduction of CO2 to CH4. Although no free H2 accumulates in the mixed cultures, the amount of H2 formed by the selenomonads can be calculated from the amount of methane produced. These studies indicate that the conventional methods for measuring H2 production by pure cultures do not provide an adequate estimate of an organism's potential for forming H2 in an anaerobic ecosystem when H2 is rapidly used, e.g., for formation of CH4.


Assuntos
Bacillaceae/metabolismo , Bactérias/metabolismo , Hidrogênio/metabolismo , Metano/metabolismo , Bacillaceae/crescimento & desenvolvimento , Bactérias/crescimento & desenvolvimento , Cromatografia Gasosa , Fermentação , Formiatos/metabolismo , Glucose/metabolismo , Glicerol/metabolismo , Lactatos/metabolismo
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